COMPILATION
OF
AIR POLLUTANT
EMISSION FACTORS
volume I:
Stationary Point
And Area Sources
FOURTH EDITrON
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AP-42
Fourth Edition
September 1986
COMPILATION
OF
AIR POLLUTANT
EMISSION FACTORS
Volume I:
Stationary Point
And Area Sources
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office Of Air And H«diatt«i
Office Of Air Quality Planning And Standards
Research Triangle Park, North Carolina 27711
September 196S
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This report has been reviewed b\ The Office of Air Quality Planning And Standards, U. S, Environme Hal
Protection Agency, and has been approved for publication Mention of trader ames or commercial products is
not intended to constitute e'tdorsement or recommendation for use.
Volume I
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PUBLICATIONS IN SERIES
Issue Date
COMPILATION OK AIR POLLUTANT EMISSION FACTORS
(Fourth Edition) 9/85
ill 9/85
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PREFACE TO THE FOURTH EDITION
VOLUME I: STATIONARY POINT AND AREA SOURCES
Compilation of Air Pollutant Emission Factors, AP-42, reports data on
emissions of atmospheric pollutants for which sufficient Informal ion exists
to establish realistic emission factors. The information herein is based on
Public Health Service Publication 999-AP-42, Compilation Of Air Pollutant
Emission Factors, by .1. L. Duprey, and on three ensuing r<:vl?ed atfd expanded
editions of Compilation Of Air Pollutant Emission Factors p.a published by the
U. 5. Environmental Protection Agency in February 1972, April 1973 and February
1976.
The present document comprises the Third Edition and all Supplements issued
since it appeared in February 1976. Aim. included here are seven newly revised
Sections of AP-«*2, with Information recently developed for AP-42 users. These
new data will be found in the following:
Section 4.3 Storage Of Organic Liquiis
Section 4.4 Transportation And Marketing Of Petroleum Liquids
Section 8.11 Class Fiber Manufacturing
Section 8.19 Construction Aggregate Processing
Section 11.2.1 Unpaved Roads
Section 11.2.5 Paved Urban Roads
Se-tion 11.2.6 Industrial Paved Roads
Chapters and Sections of thlr. document are arranged in <* format that
permits easy and convenient replacement of material, whenever information
reflecting more accurate and refined emission factors shsulrt be published and
distributed. For easy addition of any future materials, the loose leaf fonaac
continues to be used. This approach permits the document to be placed in a
ring binder or ro be secured by rings, rivets or other rasteners. A bottom
corner ot each Fa£e bears the date the information wan issued.
For the Fourth Editionv stationary point and fvrea (sources have been
collected as Volume T. Mobile s^arces, formerly in Chapter 3.0, are now
separated into Volume II. Also, commensurate w-th the designation of lead as
a criteria pollutant, lead emission factor? £>->nrorly in Appendix £ have been
incorporated into the appropriate Sections. For persons unfamiliar with tne
contents of AP-42, an alphabetic cross reference index has beer, added following
the Contents.
Comment'j and suggestions regarding this document are appreciated and should
be sent to iht: Director, Monitoring And Data Analysis Division, MD-14, u. S.
Enviror-ioental Protection Agency, Research Triangle Park, NC 27711.
iv
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CONTENTS
Page
INTRODUCTION 1
1. EXTERNAL COMBUSTION SOURCES 1.1-1
1.1 Bituminous Coal Combustion 1.1-1
1.2 Anthracite Coal Combustion . . 1.2-1
1.3 Fuel Oil Combustion 1.3-1
1.4 Natural Gas Combustiou 1.4-1
1. i) Liquified Petroleum Gas Combustion 1.5-1
1.6 Wood Waste Combustion In Boilers 1,6-1
1.7 Lignite Combustion 1.7-1
1.8 Bagaaei: Combustion I.i Sugar Mills 1.8-1
1.9 Residential Fireplaces 1.9-1
1.10 Wood 3toves 1.10-1
1.11 Waste Oil Disposal 1.11-1
2. SOLID WASTE DISPOSAL 2.0-1
2.1 Refuse Incineration 2.1-1
2.2 Automobile Body Incineration 2.2-1
2.3 Conical Burners 2.3-1
2.4 Open Burning 2.4-1
2.5 Sewage Sludge Incineration 2.5-1
3. INTERNAL COMBUSTION ENGINE SOURCES 3-1
Glossary Of Terms Vol. II
3.1 Hifihway Vehicles Vol. II
3.2 Off Highway Mobile Sources Vol. II
3.3 Off Highway Stationary Sources 3.3-1
A. EVAPORATION LOSS SOURCES 4.1-1
4.1 Try Cleaning 4.1-1
4.2 Surface Coating 4.2-1
4.3 Storage Of Organic Liquids 4.3-1
4.4 Transportation And Marketing Of Petroleum Liquids 4.4-1
4.5 Cutback Asphalt, Emulsified Asphalt And Asphalt Cement .. 4.5-1
4.6 Solvent Degreaalng 4.6-i
4.7 Waste Solvent Reclamation 4.7-1
4.8 Tank And Druta Cleaning 4'.8-1
4.9 Graphic Arts 4.9-1
4.10 Commercial/Consumer Solvent Use 4.10-1
A.11 Textile Fahrlc Printing 4.11-1
5. CKE.MICAL PROCESS INDUSTRY 5.1-1
5.]. Adipir. Acid 5.1-1
5.2 Synthetic Ammonia 5.2-1
5.3 Carbon Black , , 5.3-1
5.4 Charcoal 5.4-1
.r.5 nhlor-Alkali. - 5.5-1
'3.6 Explosives 5.6-1
5.7 Hydrochloric Acid 5.7-1
5.8 Hydrofluoric Acid ,. 5.C-1
5.9 Nitric Acid 5.9-1
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Page
0.10 Paint And Varnish 5.10-1
5.11 Phosphoric Acid 5.11-1
5.12 Phthalic Anhydride 5.12-1
5.13 Plastics 5.13-1
5.U Printing Ink 5-14-1
5.15 Soap And Detergents . 5.15-1
5.L6 Sodium Carbonate 5.16-1
5.17 Sulfuric AcJd 5.17-1
5.18 Sulfur Recovery 5.18-L
5.19 Synthetic Fibers 5.19-1
5.20 Synthetic Rubber 5.20-1
5.21 Terephtnalic Acid 5.21-1
5.22 Lead Alkyl 5.22-1
5.23 Pharmaceuticals Production 5.23-1
5.24 Maleic Anhydride 5.24-1
6. FOOD AND AGRICULTURAL INDUSTRY 6.1-1
6.1 Alfalfa Dehydrating 6.1-1
6.2 Coffee Roast lnj> 6.2-1
6.3 Cot f on Glnnl ng 6.3-1
6.4 Feed And Grain Mills And Elevators 6.4-1
6.5 Fermentation 6.5-1
6.6 Fish Processing 6.6-1
6.7 Meat Smokehouses 6.7-1
6.8 Ammoniua Nitrate Fertilizers 6.8-1
6.9 Orchard Heaters 6.9-1
6.1C Phosohntf Fertilizers 6.10-1
6.11 Starch Manuttctuiing 6.11-1
0.12 Sugar Cane Processing 6.12-1
6.1T Bread Baking 6.13-1
6.1-'» Urea , 6.14-1
6.15 Beef Cattle FeedloCS 6.15-1
6.16 Defoliation And Harvesting Of Cotton 6-16-1
6.17 Harvesting Of Grain 6-17-1
b.lti Amraoniua SuJfate 6.18-1
1. METALLURGICAL INDUSTRY 7.1-1
7 .1 Primary Aluminum Production 7 .1-1
1.2 Cnke Production 7.2-1
7.3 PrJranry Copper Smelting 7.3-1
7.4 Ferr'-slloy F reduction 7.4-1
7.5 Iron And Ft* el Production 7.5-1
7.6 Primary Lead Smelting 7.6-1
,'.7 Zinc Smelting 7.7-1
7.8 Secondary Aluminum Operations 7.8-1
7.9 Secondary Copper Smelting And Alloying 7,9-1
7.1'J Gray Iron Foundries 7...0-1
7.11 Secondary Lead Smelting 7.11-1
7.11! Secondary Magnesium SmeltJnj* 7.12-1
7 .1'I Slei-cl hound lies , 7.13-1
7.1^ Secondary /.tic Processing 7.14-1
7.15 8f.or.4fcr: Bait, ry Production . 7.L">-1
vl
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rage
7.16 Lead Oxide And Pigment Production 7.16-1
7.17 Miscellaneous Lead Products 7.17-1
7.18 Leadbearing Ore Crushing And Grinding 7.18-1
8. MINERAL PRODUCTS INDUSTRY , 8.1-1
8.1 Asphaltlc Concrete Plat .... 8.1-1
8.2 Asphalt Roofing 8.2-1
8.1 Bricks And Related Cl.\. Products 8.3-1
8.4 Calcium Carbide Manufacturing 8.4-1
8.5 Castable Refractories 8.5-1
8.6 Portland Cp-.ti.it Manufacturing 8.6-1
6.7 Ceramic Clay Manufacturing 8.7-1
8.8 Clay And Fly Ash Sintering 8.8-1
8.9 Coal Cleaning 8.9-1
8.10 Concrete Batching 8.10-1
8-11 G.'asa Fiber Manufacturing 8.11-1
8.12 Frit Manufacturing 8.12-1
8.13 Glass Manufacturing 8.13-1
8.14 Gypsum Manufacturing 8.14-1
8.15 Line Manufacturing 8.15-1
8.16 Mineral Woe". Manufacturing 8.16-1
8.17 Pel lite Manufacturing 8.17-1
8.18 Phosphate Rock Processing 8.18-1
8.19 Construction Aggregate Processing 8.19-1
8.20 [Reserved] 8.20-1
8.21 Coal Conversion 8.21-1
8 .22 Taconite Ore Processing 8 .22-1
8.23 Metallic Mineral* Processing 6.23-1
8.24 Western Surface Coal Mining 6.24-1
9. PETROLEUM INDUSTRY 9.1-1
9.1 Petroleum Refining 9.1-1
9.2 Natural Gao Processing ... , ... 9.2-1
10. WOOD PRODUCTS INDUSTRY in. 1-1
10.1 Chemical Wood Pulping 10.1-1
10.2 Pulpboard 10.2-1
10.3 Plywood Center And Layout Operations 10.3-1
10.4 Woodworking Waste Collection Operations 10.4-1
11. MISCELLANEOUS SOURCES 11.1-1
11.1 Forest Wildfires 11.1-1
11.2 Fugitive Dust Sources 11.2-1
11.3 Explosives Detonation 11.3-1
APPENDIX A Miscellaneous Data And Conversion Factors A-l
vli
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K£Y WORD INDEX
Acid
Adiplc 5.1
Hydrochloric 5.7
Hydrofluoric 5.8
Phosphoric 5.11
Sulfuric 5.17
Terephthallc 5.21
Adlpic Acid 5.1
Aggregate, Construction 8.19
Aggregate Storage Piles
Fugitive Dust Sources 11.2
Agricultural Tilling
Fugitive Dust Sources 11.2
Alfalfa Dehydrating 6.1
Alkali, Chlor- 5.5
Alloys
Ferroalloy Production 7.4
Secondary Copper Smelting And Alloying 7.9
Aluminum
Primary Aluminum Production 7.1
Secondary Aluminum Operations 7.8
Ammonia, Synthetic 5.2
Ammonium Nitrate Fertilizers 6.8
Anhydride, Phthalic 5.12
Anthracite Coal Combustion ] .2
Ash
Fly Ash Sintering - 8.8
Asphalt
Cutback Asphalt, Emulsified Asphalt And Asphalt Cement 4.r>
Rooting 8.2
Asphaltic Concrete Plants 8.1
Automobile Body Incineration 2.2
Bagasse Combustion In Sugar Mills 1.8
Baking, Bread 6.13
Bark
Wood Waste Combustion In Boilers 1.6
Bitr-hinR, Concrete S.10
Bacctry
Storage Battery Productiyn 7.15
Deer Production
Fermentation 6.5
Bituminous Coal Combustion 1.1
Bread Baking 6.13
Bricks And Related Clay Products 8.3
Burners, Conical (Teepee) 2.3
Burning, Open 2.4
ix
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Calciua Carbide Manufacturing 8.4
Cane
Sugar Cane Processing 6.12
Carbon Black 5.3
Carbonate
Sodium Carbonate Manufacturing , 5.16
Castable Refractories 8.5
Cattle
Beef Cattle F«edlot8 , 6.15
Cement
Asphalt 4.5
Portland Cement Manufacturing 8.6
Ceramic Clay Manufacturing , = 8.7
Charcoal 5.4
Chemical Wood Pulping 10.1
Chlor-Alkali , 5.5
Clay
Bricks And Related Clay Products 8.3
Ceramic Clay Manufacturing 8.7
Clay And Fly Ash Sintering 8.8
Cleaning
Coal 8.9
Dry .... 4.1
Tank And Drum 4.8
Coal
Anthracite Coal Combustion 1.2
Bituminous Coal Combustion 1.1
Cleaning 8.9
Conversion 8.21
Coating, Surface . 4.2
Coffee Roasting 6 .2
Coke Manufacturing 7.2
Combustion
Anthracite Coal .,...., 1.2
Bagasse, In Sugar Mills 1.8
Bituminous Coal 1.1
Fuel Oil 1 3
Internal Vol. 11
Lignite , 1.7
Liquified Petroleum CAB 1.5
Natural Gas 1.4
Orchard Heaters 6-9
Residential Fireplaces 1.9
Was r.e 011 , 1.11
Wood Stoves 1.10
Concrete
Asphaltic Concrete Plants 8.1
Concrete Batching 8.10
Conical (Teepee) Burners 2.3
Construction Aggregate 8.19
Construction Operations
Fugitive Duet Sources 11.2
Conversion, Coal 8.21
Wood Waste In Boilers ' 6
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Copper
Ptinwry Copper Smelting ........................................... 7.3
Secondary Copper Smelting And Alloying ..... ...................... 7.9
Cotton
Defoliation And Harvesting ........................................ 6.16
Ginning [[[ 6.3
r ron
Synthetic Fibers , ................................................. 5.19
Defoliation, Cotton .................. . .......... ... ................. 6.16
Degreasing, Solvent ................................................. 4.6
Lehydrating, Alfalfa ................................................ 6.1
Dt tergents
; oap And Detergents ............................................... 5.15
De-;(. nation, Explosives .............................................. 11.3
oruci
Tank. Aod Drum Cleaning ............................................ 4.8
Dry Cleaning [[[ 4.1
Dust
Fugitive Dust Sources ..................................... . ....... 11.2
Elevators, Feed and Grain Mills ................................. .... 6.4
Explosives [[[ 5.6
Explosives Detonation ............................................... 11.3
Feed
Beef Cattle Feedlots .............................................. 6.15
Feed And Grain Mills And Elevators ........................... ..... 6.4
Fermentation [[[ 6.3
Fertilizers
Ammonium Nitrate ....................... , . . . ...................... 6.8
Phoephate ........................... ............................. 6.10
Ferroalloy Production ............................... . ............... 7.4
Fiber
Glass Fiber Manufacturing ...... • .................................. 8.11
Fiber, Synthetic [[[ 5.19
Fires
Forest Wildfires .................................... ............... 11.1
Fireplaces, Residential ............................................. 1.9
Fish Processing .............................................. , ...... 6.6
Fly Ash
Clay And Fly AL.I Sintering ......................................... 8.8
Foundries
Gray Iron Foundries ..... , ......................................... 7.10
Steel Foundries ................ .................................. 7.13
Frit Manufacturing .................................................. 8.12
Fuel Oil Combustion ....................................... ......... 1.3
fugitive Dust Sources .............................................. 11 .2
Gas Combustion, Liquified Petrol eon ................................. 1.5
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Glass Hanufacturlng 3.13
Glass Fiber Manufacturing 3.11
Grain
Fe'-id And Grain Mills And Elevators 6.4
Harvesting Of Grain 6.17
Gravel
Sand And Gravel Processing 8.19
Gray Iron Foundries - 7.10
Cvpsum Manufacturing 8.14
Harvesting
Cotton 6.16
Grain , •. : 6.17
Heaters , Orchard , 5.9
Hydrochloric Acid 5.7
Hydrofluoric Acid 5.8
Incineration
Automobile Body 2.2
Conical (Teepee) 2.3
Refuse 2.1
Sewage Sludge 2.5
Ink, Printing 5.U
Internal Combustion Engines
Highway Vehicles .... Vol. II
Off Highway Mobile Sources Vol. II
Off Highway Stationary Sources 3.3
Iron
Ferroalloy Production 7.4
Gray Iron Foundries 7 .10
Iron And Steel Mill,. , 7.5
Taconite Ore Processing 8.22
Lead
Leadbearing Ore Crushing And Grinding 7.18
Mlscellaneous Lead Products , 7.17
Primary Lead Sn>eIcing , 7.6
Secondary Lead Smelting 7.11
Lead Alkyl 5.22
Lead Oxide And Pigment Production 7.16
Leadbearing Ore Crushing And Grinding 7.18
Lignite Combustion. 1.7
Lime Manufacturing 8.15
Liquified Petroleum Gas Combustion 1.5
Magnesium
Secondary Magnesium Smelting 7 .12
Ma lei c Anhydride 5.24
Marketing
Transportation And Marketing Of Petroleum Liquids 4.4
Meat Smokehouses 6.7
Mineral Wool Manufacturing 8.16
xii
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Mobile Sources
Highway , Vol. 11
Off Highway Vol. 11
Natural Gas Combustion 1.4
Natural Caa Processing 9.2
Nitric Acid Manufacturing 5.9
Off Highway Mobile Sources Vol. II
Off Highway Stationary Sources 3.3
Oil
Fuel Oil Combustion , 1.3
Waste Oil Combustion 1.11
Open Burning 2.4
Orchard Heaters 6.9
Ore Processing
Leadbearlng Ore Crushing And Grinding 7 .18
Taconite 8.22
Organic Liquids, Storage 4.3
Paint AnH Varnish Manufacturing 5.10
Paved koads
Fugitive Dust Sources 11.2
Per lite Manufacturing 8.17
Petroleum
Liquified Petroleum Gas Combustion 1.5
Refining 9.1
Storage Of Organic Liquids 4.3
Transportation And Marketing Of Petroleum Liquids 4.4
Pharmaceuticals Production 5.23
Phosphate Fertilizers 6.iO
Phosphate Rock Processing , 8.18
Phosphoric Acid 5.11
Phthalic Anhydride 5.12
Pigment
Lead Oxide And Pigment Production 7.16
Plastics 5.13
Plywood Veneer And Layout Operations 10.3
Portland Cement Manufacturing 8.6
Printing Ink 5.14
Pulpboard 10.2
Pulping, Chemical Wood , 10.1
Reclamation, Waste Solvent.... 4.7
Recovery, Sulfur 5.18
Refractories, Castable.... 8.5
Residential Fireplaces 1.9
Roads, Paved
Fugitive Dust Sources 11.2
Roads, Unpaved
Fugitive Dust Sources 11.2
Roasting Coffee 6.2
Rock
Phosphate Rock Processing 8.18
xiii
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Root lag, Asphalc 8.2
Rubber, Synthetic 5.20
Sand And Gravel Processing 8.19
Sewage Sludge Incineration..... 2.5
Sintering, Clay And Fly Ash 3.8
Smelting
Primary Copper Smelting 7.3
Primary Lead Smelting 7.6
Secondary Copper Smelting And Alloying 7.9
Secondary Lead S'JieIcing 7.11
Secondary Magnesium Smelting - 7.12
Zinc Smelting 7.7
Smokehouses, Meat 6.7
Soap And Detergent Manufacturing 5.15
Sodium Carbonate Manufacturing . 5.16
jiilvent
Commercial/Consumer Use 4.10
Solvent Degreasing 4.6
Waste Solvent Reclamation 4.7
Starch Manufacturing 6.11
Stationary Sources, Off Highway 3.3
Steel
Iron And Steel Mills 7.5
Steel Foundries 7.13
Storage Battery Production 7.15
Storage Of Organic Liquids 4.3
Sugar Cane Processing 6.12
Sugar Milla, Bagassr. Combustion In 1.8
Sulfur Recovery 5.18
Suit uric Acid 5.1V
Surface Coating , 4.2
Synthetic Ammonia 5.2
Synthetic Fiber 5.19
Synthetic Rubber 5.20
Taconite Ore Processing 8.22
Tank And Druti Cleaning 4.8
Terephthallc Acid 5.21
Tilling, Agrl:uitural
Fugitive Du;t Sources > '1.2
TransporLatlo i And Marketing Of Petroleun Liquids 4.4
Unpaved Roads
Fugitive Du ;c Sources 11.2
Urea 6.14
Varnish
Paint And Vernioh Maiiufacturlng 5.10
Vehicles, Highway And Oft Highway Vol. II
Waste Solvent Reclamation -,,7
Waste Oil Combat lion l.il
xiv
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Whiskey Production
FernentRtion 6.5
Wildfires, Forest U.I
Wine Making
Fermentation , 6.5
Wood Pulping, Chemical 10.1
Wood Stoves 1.10
Wood Waste Combustion In Boilers 1.6
Woodworking Waste Collection Operations 0.4
Zinc
Secondary Zinc Processing /.14
Smelting 7.7
xv
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COMPILATION OF AIR POLLUTANT EMISSION FACTORS
VOLUME I:
STATIONARY POINT AND AREA SOURCES
Introduction
What is an emission factor?
An emission factor Is an average value which relates the quantity of a
pollutant released to the atmosphere with the activity associated with the
release of that pollutant. It is usually expressed as the weight of pollutant
divided by a unit weight, volume, distance or duration of the activity that
emits the pollutant (e. g., kilograms of particulate i.-nitted per me gag rams of
coal combustc'). Using such factors permits the estimation of emissions from
various sources of air pollution. In most cases, these factors are simply
averages oi' all available data of acceptable quality, generally without consid-
eration Tor the influence of various process parameters such as temperature,
reactani. concentrations, etc. For * few cases, however, such as In the estima-
tion of volatile organic emissions from petroleum storage tanks, this document
contains empirical formulae which can relate emissions to each variables as
tank diameter, liquid temperature and wind velocity. Emission factors corre-
lated with such variables tend to yield more precise esti'Jiates than would fac-
tors derived from bioader statistical averages.
Recommended uses of emission factors
Emission factors are very useful tools for entimating air pollutants
from sources. However, because such factors are averages obtained from data
of wide range and varying degrees of accuracy, emis^lono calculated this way
for a given facility are likely to be different free- tiiat facility's actual
emissions. Because they are averages, the emission factor will be higher than
actual emissions for some sources and lower than for others. Only an onslte
source test can determine the actual pollutant contribution from a source,
under the conditions exintlng at the tine of the test. For the most accurate
emissions estimation, it is recommended that source, specific, data be obtained
whenever possible. Factors are more appropriately used to estimate (.he collec-
tive emissions of a number of sources, such as is done in emissions Inventory
ef fort ,1.
If factors are used to predict emissions from new or proposed sources,
the user should review the latest literature and technology to determine if
such anurces are likely to exhibit emission characteristics different from
those of typical existing sources.
In a few AP-42 Sections, emission factors are presented for facilities
having air pollution control equipment in place> These factors generally are
not intended f.o represent best available or state of: I;he art con .rol techno-
logy, rather they relate to the level of control commonly found en existing
facilities. The usefulness of this information should be considered carefully,
In light of changes in air pollution control technology. Thm«nt efficacy.
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Examples of various factor applications
Calculating carbon unoxld'.: (CO) emissions from distillate oil combustion
serves as an example of the sinplest use of emission factors. Connider an
industrial boiler which Sums 90,000 liters of distillate oil per day. In
Section 1.3 of AP-42 , the CO emission factor for industrial boilers burning
distillate oil IB 0.6 kg CO per 10^ liters of ull burned.
Then CO emissions
- CO emission factor x dlscillace oil burned/day
- 0.6 x 90
- :-4 kg/day
lu a somewhat More complex case, suppose a sulfuric acid (^£04) plant
produces T.OC Mg of 100?. ^864 per day by converting tulfur dioxide (S02) Into
sulfur trioxide (803) at 97.5% <:ff icier.cj . In Section 5.17, the S02 emission
factors are listed according to 30i to $03 conversion efficiencies, in whole
numbers. The reader is directed to Footnote b, an interpolation formula which
may be used to obtain the emission factor for 97.5% S02 to SOj conversion.
Emission factor for kg S02/Mg 100% H2SO^
- 682 - [(6.82)(% S02 to S03 conversion)]
- 682 - [(6.82)(97.5)]
- 682 - 665
- 17
For production of 200 Mg of IOOZ H2S04 per day, S02 emissions are calculated as
S02 emissions
- 17 leg S02 emissions/Ms 100% H2S04 >. 200 Mg 100X hV^/day
- 3400 kg/day
Emission Factor Ratings
To help users understand the reliability a'ld accuracy of AP-42 emission
factors, each Table (and somatinn.-s individual factors within a Table) is given
a rat?.ng (A through E, with A being the best) which reflects the quality and
the ariount of data on which the factory are based, "in genera,, .faonors based on
many observations or on more widely acctvted test procedures ate assigned higher
rankings.. For instance, an emission factor baseil on ten 01 more source tests on
different plants would likely get an A rating, if all tests were: conducted using
a single valid reference measureiLent method or equivalent techniques- Conversely,
a factor based on a single observation of questionable quality, or one extrapo-
lated from another factor for a similar process, would probably be labeled D or
E. Several subjective schemes ha^e been used i-i the past to assign these ratings,
depending upon aata availability, source characteristics, etc. Because these
ratings ara subjective and take no account of Hie inherent scatter among the
daca iisei to calculate factors, they should be used only as approximations, tc
infer trror bounds or confidence intervals about each emission factor. At
iLOEt. a raring should be considered nn indicator of the accuracy and precision of
a givtr, factor used to estimate emissions from a large number of sources. This
indicator will largely reflect the professional judgement of the, authors and
reviivtrti of AP-4?. Sections concerning cha it-liability of any estima'.es derived
with these factors.
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EXTERNAL COMBUSTION SOURCES
".xternal combustion sources incl.uda steam/electric generating plants,
inJu.'-trial boilers, and commercial .:ind domestic c..>m'iusv.i'.'n unitr,. Coal,
fii^l oil and natural 933 arr. the ra:ijor fossil fi.els utad by those sources.
Other fuels, used in relatively s'.aall i;uar.tit ?f;s, uru liquefied petroleum
gas, wood, coke, refinery gas, bl^st furnace g.is aid :>tlicv w-jste or byproduct
rue Is. Coal, oil and natural gas r.urrenc'ly ?.>uppl> ,3'iout 95 porcent. c.: fhe
tot.aJ thLMinal energy consuiied in the United States. 1980 saw nationwide
consumption1 of ovei 53G x lt)'J megagrams (535 million tons) of bituminous
coal, nearly 3.6 x 106 MU'gap.rams (4 raiiivon tons'" of ar.c'.irjcile coal,
91 x 109 liters (24 billiop gallons) of distillace oil, 1]A x 109 lict-rs
(37 billion gallons) of residual oil, and 57 x 101/; citoic meters (2C tril)Jon
cubic feet) of natural g?«6.
Power generation, process heating .ind space hf.av.iig are some of the
largest fuel combustion sources of sulfur oxides, nitrogen oxides and
particulat.e emissions. The following Sections j-vesent emission factor dc td
on the major fossil fuels - coal, fuel oil and Matural gas - and fur oth ;r
fuels ay well.
11980 National Emissions Data System (NEDS) Fuel Use Report, EPA-450/4-82-0'i,
U. S. Environmental Protp.ct.ion Agency, Research Triangle Park, N'J,
August 1982.
6/82 fxcarnal Combustion Sources 1.0-1
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1.1. BITUMINOUS AtfD SUB817UM1NOUS CJAL COMBUSTION
1.1.1 General1
Coal is a complex combination of or.'janlc matter and inorganic ash
formed over eons from .successive layers of fallen vegetation. Coal types
are broadly classified as anthracite, bituminous, subbitumlnous or lignite,
and classification is 'ji.ide by heating value* and amounts of fixed carbon,
•olatile matter, ash, s-jlfur and raoi.Kturii. Formulas for differentiating
coals baaed on these properties art- givsn in Reference 1. See Sections 1.2
and 1 . '.' '/or discusK-j: n.1; of antbrac* te rjnu lignite, respectively.
Mi ere are two n?a:,or coal combustion techniques, sr.speraion firing and
grate firing. Suspension firing is the primary combustion mechanism in
pulvr-rir,ed coal and. cyclone, systems. Gr^te firing Is the primary mechanism
in uaderfeed anJ overfeed stokers. Both mechanisms are empJoyed in spreader
stoker?;.
Pulverized coal furnaces are used primarily in utility and large
industrial boilers. In these systems, the coal is pulverized in a mill to
the consistency of talcum powder (i.e., at least 70 percent of the particles
will pass through * 200 iresh sieve). The pulverized coal is generally
entrained in primery air before being fed througn the burners to the combus-
tion chamber, whci-e it is fired in suspension. Pulverized coal furnaces are
classified as either dry or wet bottom, depending oa the ash removal tech-
nique. Dry bottc.ra furnaces fire coals with high ash fusion temperatures,
and dry ash removal techniques are used. In wet bottom (slag tap1* furnaces,
coals with low ash fusion temperatures are used, f.nd molton osh is divined
from the bo: torn ot the furnace. Pulverized ccal furnaces are. further clas-
sified by the flying position of the burners, i.e., single (front or rear)
wall, horizontally opposed, vertical, tangential (corner fix'ad) , t'jrbo or
arch fired.
Cyclone furnaces burn low ash fusion temperature coal crushed to a 4
mesh size. The c-^a] is fed '.jngentially , wit1.', primary air, to a horizontal
cylindrical combustion chambp.r. In this chamber, small coal partici*-:s are
burned in susptn iion, while the larger particle"- are. fot,:>?if against: the
outer w.-ill. Berause of the high temperatures developed in rhe relatively
small furnace vjlurie, and because of t.he low CusJ.c.i temperature, of th^ coal
aah, -Much of tlie. ash forms a liquid slag which is; drained frotf the bottow of
the furnace through a slag tap opening. Cyclone furnaces are used ;.oostly in
utility and large industrial applications.
In Kpreader stokers, a flipping mechanism throws the coal into thi;
furnace ind onto a moving fual bed. Combustion occurs partly in suaperf.ion
and oart/ly on I. he grf.te. BecauKe of significant carbon in the particulate,
8/81: External Combustion Sources 1.1-1
-------
flyrish reinjection -ro-n mechanical collectors is commonly employed to improve
boiler efficiency. Ash residue in the fuel bed is deposited in a receiving
pit at the er.d of the grate.
In overfeed stokers, coal is fed onto i traveling or vibrating
and it burns or, the fuel bed as it progresses through the furnace. Ash
particles fa..l into an ash pit at the rear of ihe sLoker. 'Die term "over-
feed" applies because the coa1. is fed onto Ithfc moving grate- undsr ;m adjust-
able gciLe. Conversely, in "u iderfeed" stokers, coal is ted intn th>> firing
zone from underneath by mechanical rams or screw conveyers. The coal moves
in a channel, known as a retort, i rnm which it is forced upward, spilling
over the tnp of earl; side to forn and to feed the fuel bed. Conbustion is
completed by the time the bed reaches the si.le dump grates from which the
ash is discharged to shallow pits. Underfeed stokers Inrlude single retort
units and multiple retort units, r.he latter having several retorts side by
side ,
1.1.2 Emissions and Controls
T»i? major pollutants of concern from external coal combustion a're
particulate, sulfur oxides and nitrogen oxides Sonic; unburnt combos.: ibles ,
including numerous organic compounds and carbon monoxide, are generally
emitted even undci' proper boiler operating conditions.
Farticulate7""4 - Particulate composition and emission levels are a
complex function of firing configuration, boiler operation and coal pro-
perties. In pulverized coal system.';, combustion is almost complete, and
thus particulate is largely comprised of inorganic ash residue. In vet
bottotr. pulverized coal units and cyclimes, the quantity of ash leaving the
bailer is less tiian in dry bottom units, since some of the ash 1 Jquif :'.es ,
collects on the furnace walls, and drains from the furnace bottom as molten
slag. In an effort to increase the fraction of ash drawn off as wet slag
and thus to reduce thr flyash disposal problem, flyash is soncciir.es rein-
jected from collection equipment into slag tap systems. Ash from dry Bottom
units may also be rejnjectf>d into wet bottom boilers for this same purpose.
Because a mixture of fine and coarse coal particles is fired in spreader
stokers, significant, unburnt carbon ci'.n be present in the p.-irriciilat-p . To
improve boiler efficiency, flyash from collection devices (typically multi-
ple cyclones) is sometimes rein j^cLed into spre'der stoker furnaces. Thic
practice can dramatically increase ihe particulate loiding at the boiJcr
outlet and, to a lesser extent, at the nechantcal collector outlet. Flynsh
can alr.o be reinjected from the liailer, air heater and ^conon.lzer dust
hoppers. Flyash reinfection fro'-, these hoppers does not increase particulate
loadings nesrly 5-0 much as from uuilLJple cyclones.5
Far L leulcitK emissions from uncontrolled ov*?.rfcud and underfeed srcikf-s
are considerably lower than fron pulverized coal units and spreadei- stokers,
since combustion takes place in a re.lativelv quiescent fuel bed. Flyash
relnjecticn is not practiced in thtse kinds of stokers.
Othtr variables than firing configuration and fly.-ish rclnjecLion cau
jffecL emissions from stokers. Particular? loadinp,s will often increase as
1.1-2 EMISSION FACTORS' 8/82
-------
load increases (especially as full load is approached) and with sudden load
changes. Similarly, particulate can increase as the ash and fines contents
increase. ("Pints" are defined in this context as coal particles smaller
than one sixteenth inch, or about 1.6 r.illlimeters, in diameter.) Converse-
ly, particulate can be reduced significantly when overfire air pressures
increased.^
The primary kinds of particulate control devices used for coal combus-
tion include multiple cyclones, electrostatic precipitators, fabric filters
(baghouaes) and scrubbers. Some measure of control will even result due to
nsh settling in boiler/air heater/economizer dust hoppers, large breeches
and chimney bases. To the extent possible from the existing data base, the
effects of such settling are reflected in the emission factors in
Table 1.1-1.
Electrostatic preclpitators (F.SP) are the most common high efficiency
control devi,-. 2 used on pulverized coal and cyclone units, and they are being
used increasJngly on stokers. Generally, ESP collection efficiencies ire a
function of collection plate are.i per volutretrJc flow rate of flue gus
through the device. Psrticulate control efficiencies of 99.9 weight percent
are obtainable with ESPs. Fabric filters have recently seen increased use
in both utility -\r\d industrial applications, generally effecting about 99.8
percent efficiency. An advantage of fabric filters is that they rre un-
affected by high flyash resistivities associated with low sulfur coals.
ESPs located after air preheaters (i.e., cold side precipitators) may operate
at significantly reduced efficiencies when low sulfur coal is fired Scrub-
bers are also used to control particul.-; te, although their primary use is to
control sulfur oxides. One drawback of scrubbers is the high energy require-
ment to achieve control efficiencies comparable to tho?e of ESPs and
baghour.es. ^
Mechanical collectors, generally multiple cyclones, are the primary
means of control en mQny stokers and are sometimes Installed upstreari of
high efficiency control devices in order to reduce the ar.h collection burden.
Depend iig on application and design, multiple cyclone efficiencies can vary
tremenaou? ly. Where cyclone design flow rates are not attained (which is
common witii underfeed and overfeed stokers), th?se Jevices may be only
marginally effective and may prove little better in reducing particulate
than large breeching. Conversely, well designed multiple cyclones, oper-
ating at the r«.-quirt;d flow rates, can achieve collection efficiencies on
spreader stokert and overfeed stokers of 90 to 95 percent. Fvtm higher
collection efficiencies are obtainable on spreader stokers with reinjected
flyash because of ""he larger particle si *.s and Increased particulate load-
ings reaching the controls.s~6
Sulfur Oxides7"^ - Gisenus sulfur oxides from external coal combustion
are largely sulfur dloxidt (S02 ) and much lesser quantities of sulfur tri-
oxide (S03) and fcasrous sulfates. These compounds form as the organic and
pyritic sulfur in the coal is oxidised during the ccmbuation process. On
ave'dge, 93 percent of the sulfur present ir. bituminous coal will be emitted
as gaseous sulfur oxides, whereas somewhat less will be emitted when subbitu-
minous co^l is fired, '"'he more alkaline nature of the ash in some subbitu-
minous coals causes, some of the sulfur to react to form various sulfate
8/82 External Combustion Sources 1.1-3
-------
TABLE 1.1-1. EMISSION FACTORS FOR EXTERNAL BITUMINOUS AND SUBBITUMINOUS COAL COMBUSTION3
w
o
z
o
H
O
yo
k*/H< ' i lb/100
101 I iv ss(i».\s; ; )»s
' I,"' ', «>•
is I JSS'liS) ' I)
H-lS'l'.V.) U511W)
njt'. t '.in
•xcl>ftr
ft.1!' * 17
.' ..o-rr*
ntrjll^J
4b" I 11 >^;:J V:-> «S(lss>
»" • ,1.bS( -'.Mi I 315(JH) I ] 2>
N.r U Irrd
its
us
MS
Mitrac«a 0»l.iw™
tt/x.
-
10. }<;.»•
it
».»
?
7
l-^
1 2>
».»
».)S
l.i
JWl»»
ll(l»l
3*
"
"
14
7.1
J.S
».i
1
Orbo* ItaMiMc*
*"_
0.)
U.I
0.]
1.4
2.5
3
1
5.5
i.i
»S
Ib'cua
0,.
0.4
u.t
%
s
b
ft
11
11
•Cl
P.04 ".O/
O.O4 ' *J.O?
O.'J*. IJ-0?
0.0*1 ; M.O-
u.m c.o-
o. o i >
o.aiv
U.Dl
0-CJ
O.oii * o.oi
I u.on : c.oi
U.Ob
0.0*
I, fcj
a.«i
0.0?
0 01
0.01}
ti.Oli
I 01.
i
• u.\
0.01
u.ul
u
) < f mni
ar i* 3 ' *d t a ro
halt cafrh) aa d*itrib«d Int«[«rt4cr 12. tffMr* paiTLlculat* It tK
rrvii*,d br •ult l^lylm a«i|h[ I till rooccnt of ea0jl («• fired) by
prior ai fired.
•cd In t«i
ouAcrlcjl
VfllL«
WCull bi ') • H. cr ^0 At/Hi (90 IWlon). T>i>- ~cut>4«^lbU' vccvr col Ire inl ID tMcfc lull cm^ch of EPA Ptatbod ") cwra
<)Z Ji tram hdlt. or I i iicr«lle~ . catch far pul^rrlud coil «nd e^ton* («ffnac««-. 101 (or BprBtfer tt.iA.trB. 1M lot
olhrr •tiArrl; «rj S'lt lor bantt ' rt-4 unit* (•«• f .-rtnen b, 14, 49).
for •ltaBln'*J« co*l, 9?I of l^cL •vlfu* It ^11*4 »• SDj, cod onl7 ibojt 0.71
will be In thi for* tit
HOT J* M|K«r can u.
IB). icr«uir o(
rtt: »*!M* 1: for [in«rfitUUr ftrrd bolUr*.
ail -d partlrult\r ^laanns, whrn Da fl> tth rclnjrctlon !• ••plovcd. '*itn cocfoi 4«Tlce Ii Intuit^, and
Factor ahovlrf bv aeplied cvca vtien fly
dlraccly •( boLl«f ovlUl t» pica UK
ACLOUitl *Jr (ly «nh Brtl'laa in an *i_i»majii»r , alt liaatar r k-Mcfcli.
iPa".ic\jiUr dtrtctl, «t boilfr njtler i/piral)y vl 1 1 M Orlc* (hit Ir
• •h 1< rr njpci^d In oclUr fraa bollrr. «lr h»«(rr i,r FroMMlvi dual
-------
UD
00
TABLE 1.1-2. EMISSION FACTOR RATINGS AND REFERENCES FOR BITUMINOUS AND SUBBITUMINOUS COAL COMBUSTION
X
f-f
•D
•^
n
o
g-
O
3
a
c
-i
Firing Cunf igui tft lun
Pulverized coal fired
Ley bo t toe.
Met bottra
Cyclone furnace
Spreader atober
Uncor trolled
after multiple cyclone
"VUh flyaali r*lo)actlor
frws cyclone
No f.'yank t* inject Ira
llam cyclone
Overfeed atoker
Uoxov. trolled
Underfeed stoker
After eultlple c>-luiiH
Handflred imU*
\nese ratings, in the cot
factor !• based on tetita
Paniculate Sulfur faldes
/tatlna Bef. a»tlnc iff.
A 14-25 A 9,16-19,21
51-37, M.
41-kb.Sl-l
D 14.16,24 A
D U.19.22, A
27-rs
» .;,3O-15 A
1 U.J2.J6-J8 A "
A 17,31-Jb, A "
t ».. 11. 41-43. A
B 6,41.44-4} A "
t k. it ,47-48 8 19.4B
C 6 1 "
D *V-M 0 "
iceat of thla Section, refer to the number of
at ten or nor* boiler* , a "V ratlna on *la t
Nitroeen Ovldea
Hatlnav bf.
, A 11.14,16-1).
21,44,56
iS
C J4.16
1 11
A Jl. 17,51-57
A
A
A 11,17.19.
41-4S
8 19,47-48
8
D 50
teat data on vfclcb e*ch
Carbon tionoiiid^
Eatlij. Bel.
A 14,16-11,21
47,57
A
A "
A 17,19.11-M
36.47,51
A
A
• 17,41-47,45
41.41
8
• 19,47-48
B
D 50
eaUacion factor 1*
NonaetheJte VOC
Batlut. !•(.
A 55,58
A 58
.
•
A "
4 *"
*
A
A 47.58
A "
0 SO,S8
burd. An "A" ratli
Methane
Kat j» «•{.
A 38
A "
A "
A "
A "
A
A
A
A 47, Si
A
D 5O.5B
i mMf the
A "o" ratine, Indlcatra the factor it M**d on only * llntl* data or eltrapolated fror a aecondarr reference. Thea* r&tlnga are not a •e^iaure of
the. acacter in the uvlcriylof tent data. However, a higher rating Hill geacraJly laercat* con (i dance that a given factor will belter aparnilMt*
Lhe. average ••iae.lona for a parLicuJat boiler category.
-------
salts that are retr.ined in the boiler or in the flyash. Generally, boiler
size, firing configuration and boiler operation have little impact on th-i
percent conversion of fuel sulfur to sulfur oxides.
Several techniques are used to reduce sulfur oxides from coal combus-
tion. One way is to switch to lower sulfur coals, since sulfur oxide emis-
sions are proportional to the sulfur content of the coal. This alternative
may nor: be possible where lower sulfur coal is not readily available or
where a different grade of coal cannot be satisfactorily fired. In some
cases, various cleaning processes may be employed to reduce the fuel sulfur
content . Physical coal cleaning removes mineral s.jlfur such as pyrite but
is not effective iu removing organic sulfur. Chemical cleaning and solvent
refining processes are being developed to remove organic sulfur.
Many flue gas desulf urization techniques can rem^'T; sulfur oxides
formed during combustion. Flue gases can be treated through wet, semidry cr
dry desulf urization processes cf either the throwaway type, In which all
waste streams are discarded, or the recovery (regenerable) type, in which
the SOx absorbent is regenerated and reused. To date, wet systems are the
most commonly applied. Wet systems generally use alkali slurries as the 3 Ox
absorbent medium and can be designed to remove well in excess of 90 percent:
of the incoming SOx.7 Participate reduction of up to 99 percent is also
possible with wet scrubbers, but flyash is often collected by upstream ESPs
or baghouses to avoid erosion of the desulf urizatioa equipment and possible
interference with the process reactions. Also, the volume of scrubber
sludge is reduced with separate flyash removal, and contamination of the
reagents and byproducts is prevented. References 7 and 8 give more details
on scrubbing and other SO^ removal techniques.
Nitrogen Oxides p~1 - Nitrogen oxides (NOy) eroissicnE from coal
combustion are primarily nitrogen oxide (NO). Only a fev volume percent are
comprised of nitrogen dioxide (N02). NO results from tht-rtpal fixation ci
atmospheric nitrogen in the combustion flame and frcm oxidation of the
nitrogen bound in the coal. Typically, only 20 to 60 percent oi" the fuel
nitrogen is converted to nitrogen oxides. Bituminous and subbituminous
coals usually contain from 0.5 to 2 weight percent nitrogen, present mainly
in aromatic ring structures. Fuel nitrogen can account for up to 80 percent
of total NO from coal ccmbus'rlon.
A number of combustion modifications ran be made to reduce NOx emis-
sions from boilerp. Low excess air (LEA) firing is the most widespread
control modification, because it can be practiced in both old and nev units
and in all sizes of boiler^. LEA firing is easy to tmpleraevi!. and has the
a-^ded advantage of increasing fuel use efficiency. LEA firing is generally
only effective above 20 percent excess air for pulverized coal units and
above 30 percent excess air for stokers. Below these levels the N<\ reduc-
tion due to decreased 0-> availability is offset by increased NOX dvo Lo
increased flame temperature. Another NO^ reduction technique is simply to
switch to a coal having a lower nitrogen content, although many boilers may
not properly fire coi-ls of different properties.
Of f-stoichiometi ic (staged) combustion is alr.o an effective mtsai.s of
controlling NOx from coal fired equipment. This can hp achieved by using
3.1-6 EMISSION FACTORS 8/82
-------
overfire air or lov NO>; burners designed to stage combustion in the flame
zone. Other NUx reduction techniques include flue gas rocirculation, load
reduction, and r.term or water injection. However, thase techniques are not
very effective for use on ~oa1 fired equipment because of the fuel nitrogen
effect. Amr.onia injection is another technique which can be used, but it is
costly. The net reduction of KOx froin any of these techniques or combin-
ations thereof varies considerably with boiler type, coal properties and
exist!-,£ operating practices. Typical reductions will range from 10 to 60
percent. References 10 sud 60 should ut- consulted for a detailed discussion
of eacli of these NOX reduction techniques. To date, flue gas treatment is
net used to reduce nitrogen oxide emissions due to its higher cost.
Volatile Organic Compounds and Carbon Monoxide - VolaLJle organic com-
pounds (VOC) and carbon monoxide (CO) are unburnt gaseous combustibles which
are generally emitted in quite small amounts. However, during startups,
temporary upsets or other conditions preventing complete combustion, unburnt
combustible emissions may increase dramatically. VOC and CO emissions per
unit of fuel fired are normally lower from pulverized coal or cyclone
furnaces than froai smaller stokers and handfired units where operating
conditions arc not as well controlled. Measures used for NOx control can
increase CO emissions, so to minimize the risk of explosion, such measures
are applied only to the point at which CO in the flue gas reaches a maximum
01 about 200 parts per million. Control measures, other than maintaining
proper combustion conditions, are not applied to control VOC and CO.
Emiss;on Factors and References - Average emission factors for
bituminous and subbituminous coal combustion in boilers are presented in
Table 1.1-1. The factors for underfeed stokers and handfired units also may
be applied to hot air furnaces. In addition to fc-ictors for uncontrolled
emissions, factors are also presented for emissions after multiple cyclones.
Emission factor ratings and references are presented in Table 1.1-2.
Further general information on coal, combustion practices, emissions and
controls is available In the references cited above.
8/82 External Combustion Sources 1.1-7
-------
References for Section 1.1
L" Stean.. 38th Edition, Babcock and Wilcox, New York, 1975.
2. Control Techniques for Participate Emissioiis from Stationary Sources,
Volume^ I. EPA-450/3-81-005a, U.S. Environmental Protection Agency,
Research Triangle Park, NC, April 1981.
3. ibidem. Volume II. EPA-450/3-81-005b.
4. Electric Utility Steam Generating Units: Background Information for
Proposed Participate hatter Emission Standards. t'PA-450/2-78-006a, U.S.
Environmental Protection Agency, Research Triangle Park, NC, July 1978.
5. William Axtman and Mark A. Eleniewski, "Field Test Results of Eighteen
Industrial Coal Stoker Fired Boilers for Emission Control and Improved
Efficiency", Presented at the 74th Annual Meeting of the Air Pollution
Control Association, Philadelphia, f\, June 1981.
6. Field Tests of Industrial Stoker Coal Fired Boilers for Emission Control
ar.d Efficiency Improvement - Sites L1-L7. EPA-600/7-81-020a, U.S.
Environmental Protection Agency, Washington, DC, February 1981.
7. Control Techniques for Sulfur Dioxide Emissions from Stationary Sources,
2nd Edition, EPA-450/3-81-004, U.S. Environmental Protection Agency,
Research Triangle Park, NC, April 1981.
8. Electric Utility Steam GeneratingUnits: Background Information for
Proposed S02 Emission Standards, EPA-450/2-78-007a, U.S. Environmental
Protection Agency, Research Triangle Park, NC, July 1978.
9. Carlo Castaldini and Meredith Angwin, Boiler Design and Operating
Variables Affecting Uncontrolled Sulfur Emissions from Pulverized Coal
Fired Steam Generatora, EPA-450/3-77-047, U.S. Environmental Protection
Agency, Research Triangle Park, NC, December 1977.
10. Control Techniques for Nitrogen Oxj-des Emissions from Stationary
Sources, 2nd Edition, EPA-450/1-78-001, U.S. Environmental Protection
Agency, Research Triangle Park, NC, January 1978.
11. Review of NOy EmissionFactors for Stationary Fossil Fuel Combustion
Sources, EPA-450/4-79-021, U.S. Environmental Protection Agency,
Research Triangle Park, NC, September 197').
~2. Standardsof Performance^ for New Stationary Sources, 36 FF 24876,
December 23, 1971.
13. Lou Scinto, PrinarySulfat? Emissions from Coal and Oil Combustion,
EPA Contract Number 68-02-3138, TKU Inc., Redondo Beach, CA, February
1980.
1.1-8 EMISSION FACTORS 8/82
-------
14. Stanley T. Cuffe and Richard W. Gerstle, Emissions from Coal Fired
Pover^ Plants: AComprehensive Sunmary, 999-AP-35, U.S. Department of
Health, Education and Welfare, Durhsm, NC, 1967.
15. Field Testing: Application of Combustion Modifications To Control NQx
Emissions from Utility Boilers. EPA-650/2-74-066, U.S. Environmental
Protection Agtncy, Washington, DC, June 1974.
16. Control of Utility Buller and Gas Turbine Pollutant Emissions by
Combustion Modification - PhaseI. EPA-600/7-78-036a, U.S. Environmental
Protection Agency, Washington, DC, March 1978.
17. Low-sulfur Western Coal Use in ExistingSmall and Intermediate Size
Boilers, EPA-GOO/7-78-153a, U.S. Environmental Protection Agency,
Washington, DC, July 1978.
18. Hazardous Emission Characterization ot Utility Boilers,
EPA-650/2-75-066, U.S. Environmental Protection Agency, Washington, DC,
July 1975,
19. Application of Combustion Modifications To Control Pollutant Emissions
from Industrial Boilers -I-haseI, EPA-650/2-74-078a, U.S. Environmental
Protection Agency, Washington, DC, October 1974.
20. Field Study To Obtain Trace Element Mass Balances at a Coal Fired
Utility Boiler, EPA-600/7-80-171, U.S. Environmental Protection Agency,
Washington, DC, October 1980.
21. Enviunmental Assessment of Coal- and Oil-firing In a Controlled
Industrial Boiler, Volume II, EPA-600/7-78-l64b, U.S. Environmental
Protection Agency, Washington, DC, August 1978.
22. Coal Fired Power Plant Trace Element Study, U..l>. Environmental
Protection Agency, Denver, CO, September 1975.
23. Source Testing of Duke Power Company, ?lezerf SC, EMB-71-CI-01, U.S.
Environmental Protection Agency, Research Triangle Park, NC, February,
1^/i.
24. John W. Kaakinen, etal., "Trace Element Behavior in Coal-fired Power
Planns", Environriental Science and Technology, ^9) : 862-869, September
1975.
25. Five Field Performance Tests on Koppers Company Precipitator, Docket
Nur.bcr OAQPS-7U-1, Office of Air Quality Planning and Standards, U.S.
Environmental Protection Agency, Research Triangle Park, NC, February-
March 1974.
26. H. M. Rayner ami L. P. Copian, Slag Tap Boiler PerformanceAssociated
with Fewer Plant Flyash Disposal, Western Electric Company, Hawthorne
Works, Chicago, IL, undated.
8/82 External CombustLon Sources 1.1-9
-------
27. A. B. Walker, "Emission Characteristics for Industrial Boilers", Aiv
.irie.erJLn.i, 9/8):17-19, August 1967.
2 8 . Environmental Assessment of Coal-fired Controlled Utility Boiler ,
EPA- 600/7-30-086, U.S. Environmental Protection Agency, Washing Lou , DC:,
April 1980.
29. Steam, 37th Edition, Bahcock and Wilcox, New York, 1963.
30 . Industrial Boiler: £miasior. Test Report, Fonrica Corporation,
Cincinnati, Ohio. EMB-80- 1BR-7 , U.S. Environmental Protection Agenc",
Research Triangle Park, NC, October 1980.
31. Field Tests of Industrial Stoker Coal-fired Boilers for Emissions
Control and Efficiency Improvement - Site A. EPA-600/ 7-7 8- 136a~, U.S.
Environmental Protection Agency, Washington, DC, July 1978.
32 • ibidem-Sice C, EPA-600/7-79-130a, May 1979.
33. ib idem-Site E, EPA-600/ /-80-064a, Marc'; 1980.
34. ibidem-aite F. EPA-600/ 7~80-065a, March .'.980.
35. ibidem-Site C, EPA-600 '7-80-082a, April 1980.
36. ibidem--Site B, EPA-600/7-79-041a, February 1979.
5 7 . Industrial Boilers: Emia s ion Jtest. Report, General Motors Corporation ,
Pant!a_. Ohio, Volune 1, EMB-fiO-IBR-4, U.S. Environmental Frotco tic;:
Agency, Research Triingle Ptrk, NC, March 1980.
3 8 • A Field Tost Using Coal ; dRDF Blends in Spread ,_er S to '.cer-fired Boll er s ,
EPA-600/2-80-095, U.S. Environmental Protection Agen.y, Cincinnati, OH,
August 1980.
3 9 . Industrial Boilers: Emission Test Report, Rlckenbacker Air Fore ; e . Ba_se_ ,
Columbus , Ohio, EMB-8Q-IBR-6, U.S. Environmental Trotection Agency,
Research Triangle Park, NC, March 1980.
4 0 . Thirry-day Field Tests of Industrial Boilers: _ Site 1,
EPA-600/7-80-085a, U.S. Environmental Protection Agency, Washington,
DC, April 1980.
4 1 . Field Tests of Industrial Stoker Coal-fired Boilers for Emiss ions
Control and Efficiency Improvement - Site D, EPA-600/ 7-79-237a"," U. S .
Environmental Protection Agency, Washington, DC, November 1979.
42. jbidem-Site H, EPA-600/ 7-80-11 2a, May 1980.
43. Ibidem-Site I, EPA-600/7-80-1 36a, May 1980.
44. il; idem-Site J, F.PA-600/7-80-137a , May 1980.
1.1-10 EMTSS ON FACTORS
-------
45. ibid€m-SlLa K, EPA-600/7-80-138a, May 19'M.
4 6 . Regie nal Air Pollution Study; Point Source Emission Inventory ,
EPA--600/4-77-014, U.S. Environmental Protection Agency, Research
Triangle Park, NC, March 1977.
47. R. P. Hangebrauck, et al. , "Emissions of Polynuclear Hydrocarbons and
Othtr Pollutants from Heat Generation and Incineration Process",
Journal of the Air Pollution Control Association, 1.4/7} : 26 7 -278, Julv
48. SOUL'CR Assessment: Cual-fired Industrial Combustion Equipment Field
Te&_ts_, SPA-600/2-78-0040, U.S. Environmental Protection Agency,
Washington, DC, June 1978.
4 9 . Source Sampling Residential Fireplaces for Emisa ion Factor Development ,
EPA-450/3-76-010, U.S. Environmental Protection Agency, Research
Trxangle Park, NC, November 1975.
50 . Atmospheric Emissions f rom Cp^^ Combustion : An Inventory Guide,
99~9-AP-24, U.S. Department of Health, Education and Welfare, Cincinnati,
OH, April 1966.
5 1 . Application of Combustion Mod if ication To Control Pollutant Emissions
from Industrial Boilers - Phase II, EFA-600/2-76-0<36a,, U.S.
Environmental Protection Agency, Washington, DC, April 1976.
5 2 . Continuous Emission Monitoring for Industrial Boiler, General Mo to rs
Corporation, St. Louis, Missouri^ Volip.e_ 1, EPA Contract Number
68-02-2637, GCA Corporation, Bedford, MA, June 1980.
53. Survey of ?lue Gas Desulfurization Systems^ Cholla Station, Arizona
Public Service Company, EPA-600/7-78-048a, U.S. Environmental Protection
Agency, Washington, DC, March 197B.
5 ^ • ibidem : La Cygne Station, Kansas Ci i:y Power and Light ,
£PA-600/7-78-048d, March ]9/8.
55. Source Assessment : Dry Dottom Utility BoiJers Filing Pulverized
Bituminous Coal, EPA-600/2-79-019, l.S. Environmental Protection Agency,
Washington, DC, August 1980.
5 6 . r,1i ir_t y— day Fiej.d Tests of Industria . Boilers: Site 3 - Fulveri^ed-
V.".'ril-'fired Boiler, EPA-600/7-80-085:, U.S. Environmental Protection
agency, Washington, DC, April 1980.
5 7 . Sy s^cmatj c Field Study_ o_f Nitrggen Oxide Emission Control Methods for
Utility Boilers, APTD-1163, U.S. Environmental Protection Agency,
Research Triangle Park, NC, December 1971.
8/82 Extern.il Combust:,.on Sot.rces 1.1-11
-------
58. Emissions of Reactive Volatile Organic Compounds fromUtility Boilers,
EPA-600/7-80-111, U.S. Environmental Protection Agency, Washington, DC,
May 1980.
59. Industrial Boilers; Emission Test Report, DuPont Corpor .\t:i onL
Parkersburg, West Virginia. EMB-80-IBR-12, U.S. Environmental
Protection Agency, Research Triangle Park, NC, February 1982.
60. Technology Assessment Report for Industrial Boiler Applications;
Combustion Modification, EPA-60U/7-79-178f, U.S. Environmental
Protection Agency, Research Triangio Park, NC, December 1979.
1-1-12 EMISSION FACTORS 8/82
-------
1.2. AHTHRACITK COAI. COMUHSTION
i-i
1.2.1 Centra I
Antliracite coal is a hi^li rank coal wi th a ;iis',l> t ixci Carbon coiiti'nt .in.!
low volatile matter content, relative r<> hitarinous c.ial and lip.nitf.1, am! it
has higher ignition ami ash fusion ti- npr ra tn ri-s . Bc'CMose of its lou volatilr
matter content and slight c.\ i nkiM i m; , a:i thr.-u- 1 v-- is no^r ..nr.nnor. 1 y firrvl in
medium si. sod travel iay gr.it.' stoker-; and small n::ui f 'i r-.'i! units. S'o;ru>
anthraoi te (cuccpi vinPy alonj; uitl'i pi.- 1 rolfini i-o'r.o) i-. i^-i/J i,i ful vt:ri/.t',i >.-.i>:il
boilers. T r is a!.^1 hU-nili'it wit') hi tur, i noc.t, i-:).il . Vu 10 is fired in
ler stok^-::. iVuMiisf or it^ T--^ s-.ilfir- i:on ttvit. (typu-.illy U-ss tli;:n O.H
weight pnrc.eut) .4 id minim;il s.Tt;'\ iiij1, teiKli"ic ios , .»n r ';::'•.• i ~v is v.'oi!.-: i.'icn.'vl .1
l« fuel w!i»rn n'.idily ;v.iiliiM«:.
In the United States, all .in thrnc; i to is minerl in NorthtJIT amounts arc . -.1-1 1 •••;•,•• ••'
for s tuam/ slf c t r ic pruilucLion; i-oki na;; i^ •(• tur i ;i}:, .-; in tor i HI' a:'n'. ; >c \ 1 •' I i :••, L'iy. ,
and other iiid'i.1? t rial usi's. Ar.tbraci t«' cc>ir,i)iis t \o\\ i-n cron 1 1 y i ^ .inly a s::i.:«)l
fraction of tin- t.ital quantity v>f ccial »:i>inhus ti'd in th«- Hnit.t'd .'"t ites.
2-l't
1.2.2 Emissions and Controls
Part Lciilatf cm issioiu-i from anthracite i.' ^'insti'in ar-> a furvtior, ol funuice
firing configuration, firing practiLe^ (h.->ilt'r load, quant Jty a u', l.j/ttio.i of
undprflre air, soutblnwi ny , t'lyash re i.n jiu: t iov , eti'.^, an,' r'te ash c.'iitiMif iif
the ro/il. Pulverised coal fired hollers i^nil t!uj !ii^h(>--!t ijua-irity of particulate
per anit of f\Kjl hocaiise tlu-y Tirf tlie antiivac L t*: in K.^.I-HMIS icn, whii-b. r^sii' ts
in 3 high poccertag*.' uf asli cariyovijr into t!i< i-xhau.-it ;ii
anthracite firr! hoilcra operate in the t!r" t.ip <>r ':rv l\)ttnir. i:ioi!i> Wcan^r-- of
antnracite's chrir*irtcris tical ly hij'Ji asii fii:-;io'i t >.ra t>ir.'. Travel i n^i >;rate
stijker.-i and hand fired units produce iniu'li loss ;• irt icnl at <• ;'n t f leant
ash cnrvyovii" into tlif t' 'missions J'r.vn
traveling gra'.i.' stokers will iucreas-; il-iri!i;; s >i. 1 1;! owi ,\i; 'ini! t' ! vM.sh re inject i on
and with higher fuel hc-d u'uied air friur f.-rc.tv draft f^is. ^Akinj; i i
rarely a problem bdr.;,usr; of anihrac i t ij ';-' low volatiU- ::i;ut.T i-ontcnf.
Limited data art- avn'lahlc on the i-nt •;;; • IMI ,>' jinsi- mr. j-o ! 1 n t ,ci r •:- fron
anthracite conbustion. Ft is arimi.no' frmn hi tuminou- co il romhus t i .'••. ij.itii
that ft large fraction of thi> fu< 1 suifur is nittt'd as sulfur o-iaci,!-:. Also,
because combustion I'quiprntMi t , oxcos,; :-ir ra:<..i, foiilius t ion ti "i pcra turos , i'tc.,
are similar bc'tw.'Oii ! L-pniiiou;: i.oal c-.i'.'iai^ ! i on , ni Lr .jf-.oii nMiil»-
and c-irhon n'onoxidi1 emissions an- .i.s»umi?d '.o b<> similar, too. Volatilt- organic
compound (VOC) emissions, tmwt'\'«.-r , ar>.' L-xp.'ctod t, bo cons iru-'- il'l y lowi;r
because tlie volatile m-itt-.:r oouti'iii of ai, ilirac: i t^ ,s s ij'i: i •" Iran! I v H-ss tlirui
that iif bitumlnoa1- co-il .
5/83 VAC TIKI! i.'onbjstion Sources 1.2-1
-------
1ABLK L.2-1. UNCONTROLLED EMISSION FACTORS FOR ANTHRACITK COMBUSTION'
Sal far
n c
Par ticulates Oxides
\T-
r~i
o
•z.
-f
ACTOR
L-UiJtil 1/Fe
kp.'Mg Ih/ton -g/Msr,
Puivcii-e.i ccal
fired f f 19. 5S
Traveling grate
stoker A.bs 9. I8 19. 5S
Hand fed units 5h I0h I9.5S
factors are for uncontrolled emissions
Nitrogen Carbon VOC
Oxides Monoxide Nonne thane Methane
Ib/ton kg/Mg
395
39 S
39S
and
9
5
1.5
Ib/ton kg/Mg Ih/ton
13 f f L
10 0.3 0.6 f
3 f f f
f
f
f
should be applied to coal conscription as fired.
d on EPA Method 5 (front half c-itch).
Based o-r. tht> .i^aumpM'on thar, m with hituminous coal combustion, most of the fuel sulfur is emitted as
fur oxides. Limited dat-i in Reference 5 verify this assumption for pulv»it L/,eJ anthracite firtd
boilers. Most of these emissions ar-? S02l with 1 - 3% S03. S Indicatos thnt the weight percent of
, siil fur in tht oil should be multiplied by the value given.
'.-'or pulverized ant.hr -acite fired boilers and hand fed units, assumed to be similar to bitunincniR coal
ronhnstion. For traveling grate stokers, see Refeto.'ices 3 and 11.
May increase, by several (Triers of magnitude if a boiler is not properly operated or inaintainc") . Fictors
for traveling grate stokers are. b-ised on limited inf .irm.ition in Reference a.. factors for pulverized
ccoal fired boilers substantiated by additional datq In Reference 14.
IEr.tission fact.ir reported in Table 1.1-1 may he used, based on the similarity of anthracite an-l bituminous
coal .
o
References 12-13, 15-18. Accounts for limited fallout that niay '?ccur in fall-Tit eV-imbers and stack
brpec.hing. Emission factors for individual boilers may range from 2.5 - ?3 kg/Mg (5 - 50 Ib/ton) and as
-hhigb as 25 kg/Mg (50 Ib/ton) during sootblowing.
"Reference 2.
-------
Control of era is si ins from anthracite combust iun !ia:s mainly been limited
to partlculate matter. The raoit efficient paniculate controls - fabric
filters, scrubr>'i:.-, and electrostatic precipltatcrs - have been installed on
l.Tgu pulverized anthriclte (Lrec. boilers. Fabric filters and venturi scrubbers
ctn effict collection efficiencies exceeding 99 percent. Electrostatic
precipi. tators, on the other N.and, are typically only 90 to 97 percent efficient,
because of the characteristic high resistivity jf low sulfur anthracite flyash.
It Is reported that higher of.: iciencles can be achieved using larger precipitators
and flue gas rottdl tlonlnp,. Mechanical collectors are f rirqm.-nt ly employed
upstream from these device1; for large par.iif.le removal.
Travel ivig grate stokers are often uncontrolled. Indeed, partlculatf
control has often been considered unnecessary berause of anthracite's low
rtir.uking tendencies and of th<> fact that a significant fraction of large size
ftyash fror; stokers Is readily collected in flyash hoppers as well as in the
breeching and b.i.se of the slack. Cyclone collectors have been employed on
traveling grate stokers, and limited information suggests these devices may be
up to 75 percent efficient on particulate. Flyash relnjectlon, frequently
used in traveling grate stokers to enhance fuel use efficiency, tends to
increase pirticulatt.' emissions per unit of fuel combusted.
Emission factors fc.r anthracite combostIon ar^ presented in Table 1.2.1,
and emission factor ratings in Table 1.2-2.
TAHI.F, 1.2-2. ANTHRACITE COAL KMISSIJ1-! FACTOR RATING*
Solfir Nltrocen C-trbon V(;C
Furnace Type Par»lculates Oxides »xiil- 077,1, .'(!. S. Envi-
t iirn.(!?n t.-il i'rMtection Agpncy, Res^circh Triangle P.nrk, Ml, Mnrc'i 1976.
)/83 F.xternal Combntj? Lc-n Sources 1.2-3
-------
6. R. P. Janasd, "Baghouse Dust Collectors on a l.ow Sulfu^ Cnal Fired Utility
Boilor", Presented at the £7th Annual Meeting o: the Air Pollution Control
Association, Denver, CO, June 1974.
7. J. H, Phelan, et al . , Design and Opfcration Experience with Bqghouse Dust
Col lectors for Pulverized Coal Fired Utility boilers - Sunbury StatjLpji,
HJ! tvood S tation, Proceedings of rhe American Power Conference, Denver,
CO, 1976.
8. Source Test Data on Anthracite Fired Travel ing Grat'3 Stokers. Office of
Air Quality Planning and Standards, U. S. Environmental Protection Agency,
Research Triangle Park, NC, 1975.
9, Source and Emissions Information on Anthracite Firea Boilers, Pennsylvania
Department of Environmental Resources, Harrisburg, PA, September 27, 1974.
10. R. J. Milligan, et al. , Review of MOX Emission Factors for Stationary
Fossil Fuel Combustion Sources^ EPA-450/4-79-021. U. S. Environmental
Protection Agency, Research Triangle Park, NC, September 1979.
11. N. F. Suprer.ant, e t a j. . , ^Emissions Assessment of Conventional Stationary
Combustion Systems, Volume IV; Commercial/ Institutional Combustion
Sources, EPA Contract No. 63-02-2197, GCA Corporation, Bedford, MA,
October 198U.
1 2 . Source^ Sampling of Anthracite Co.'il Fired Boilers, RCA-Electronic Components,
L3.r.c_3s_ter , Pennsylvania^ Final Report, Scott Environmental Technology,
Inc., Plumsteadville, PA, April 1975.
1 3 . Source Sanplin^; or Anthracite Coal Fin-d Boil erat Shlnpensburg State
Col lege , Shippensbu rg , Perms y 1 vania , Fina 1 Rtijo 1 1 . Scotl cnvironmeiit.-'.l
T«c.hncilogy, Inc., Plamsteadvil le , PA, May 1975.
14. W. Bartok, et al . , Systematic Field Study of NUx Emis.aion Control
Methods for Utility Boilers, APTD-H63, U. S. Environmental Protection
Agency, Research Trianj-le Park, NC, December 1971.
1 5 . Source Sampl in^ of Anthraci fj Co:urc«f,, Harr-!(iburg, PA, January 29,
1 7 . Source Sanp lin^ of A-. th rs cite Coal Firod Rolli.rs, Per'ninii s t Center,
Spring Cit;, Pennsylvfanla, Final Report, THC Envir.jni;ient.'il Consultants,
Inc., 'Jlil'iersf ipld. '.T, Januory 2'i, 1°SO.
18. Sojrc<5 Sarepli^ig of Anthracite Coal Tir^'i h'jilers, Vest Cheater Stat^,
West _Jhc"-:ler, Pennsylvania, final Ropru i. . Rrjy" Ues t-Jri, ] nc . , West Chester,
PA, ^ril 4, 1977."
1.2-4 EMI',S[MN FACTORS
-------
1.3 FUEL OIL COMUUSTIUN
i - i r- ,1.2,22
1..-I.1 f-eneral
Fuel oils are broadly classified into two major types, distillate
and residual. Distillate oils (fuel oil grade Nos. 1 and 2) are
us'iri mainly in domestic and siaall commercial applications In which
easy fuel burning is required. Distillates are more volatile and
less viscous than residual oils, having negligible ash and nitrogen
contents and usually containing less th«?.n 0.3 weight percent sulfur.
Residual oils (grdde Noa. A, 5 and 5), on the other hand, are used
mainly in utility, industrial and large commercial applications
with sophisticated combustion equipment. No. 4 oil is sometimes-
classified as a distillate, and No. 6 is sometimes referred to as
Bunker C. Being more viscous and less volatile than distillate
oils, the heavier residual oils (Nos. 5 and 6) mu-jt be heated to
facilitate handling and proper atomiz.uiou. Because residual oils
are produced frou the residue left after lighter fractions (gasoline,
kerosene and distillate oils) have been removed from the crude oil,
they contain significant quantities of ash, nitrogen and sulfur.
Froperties of typical fuel oils are f.lver. in Appendix A.
1.3.2 Emissions
Emissions from fuel oil combustion are dependent on the grade
and composition of the fuel, the type an-i size of the boiler, the
firing and loading practices used, and the Isvel of equipment
maintenance. Table 1.3-1 presents emission factors for fuel oil
combustion in units without control equipment. The emission factors
for industrial and commercial boilers are divided into distillate
and residual oil categories because the combustion of each produces
significantly different emissions of particulates, SO and NO .
The reader is urged to consult the references for a detailed
discussion of the parameters that affect emissions from oil combustion.
Part iculatu Matter ' * ' - Participate emissions are moist
dependent on the grade of fuel fired. The lighter d'.stillate oils
result in significantly lower ^articulate formation than do the
heavier residual oils. Among residual oils, Nos. A and 5 usually
result in less particulate than does the heavier No. 6.
In boilers firing No. 6, partlcu'late emissions can be described,
on the average, as a function of the sulfur content of the oil. A.s
shown in 'iahle 1.3-1 (Footnote g), particulate enissions can be
reduced considerably when low-sulfur grade 6 oil is fired. Thi.s is
because low sulfur No. 6, whether refined fron naturally occurring
low sclfur crude oil or desulfurized by one of several curre-ic
processes, exhibits substantially lower viscosity and reduced
zisphaltene, ,\t,\t and sulfuv - all of which results in better
a r.omlzatirjrt and cleaner combustion.
8/82 E.xtKraal Combustion ^Tjr
-------
•n
CXI
^.^
|VJ
TAB!.-: I.I-1.. UNCONTROLLED EMISSION FACTORS FOR FU£L OIL COMBUSTION
HUSSION FACTOR RATING: A
r'antri.--. ".ilfur hlr»1d>- Snlfur Carbon Nitrogen il»ld» vuljtl1f
•(.ill •. Trlcxlde Monoild*' Hannethine
PHI i. r T p<-
lb/'0JR»l kt/103! lp/103ial kg/103! lh/lnj|ial ko/lo'l Ib/io'ii-l k«/lo'l lb/IOJg«l kg/101] Ih/lo1ga
4 6; 4 0.1)9 P.7(. 0.01 0.78
T.nd-.~: r • .-I I Wol Irrs
li.--.Jinl i-n * . !«!• 1S7S O.Z4S
t:. still lie "II 0.24 - I7S I"-?S 0.24S
C..-T. ..--.I B i Iprs
'.•^iU'J.i! '"-I B » !lt' '';'s "• -4S
..!.= « •:..,!.. on i;.ji .• i •• i'.;'.; -..-«!!
Rt^j'-' -il -.al rurnac*"*
:>!•.! ii .UP i ii •-'. ) .:.- :.'s !»:•." o.;»s
'Vo.ii-r- -:m K, -ippr o» i-nalri , ,-i.i.^lflrl :,crndlnt. to the.r gr.x>a
.Hill • i|,njer pi;, nil boiivrs. ^\Qt> » lo''* J/hr i>lf|l> K 10" »t
inonsir:,,i bi'tlpr^: ".0.-< n 10 ' to i'X. « In9 j /hr (10 « ii!" tn
.,-Tiwrr:.il b»ller.s: :i.'; » 1 0 ' !•.' I'i.fc • I1.' If'ir (:)."• • .; '
i4'-.ii-.:il 'unuicp«: ! J-.»/hr>
to 11 « iO''' 3t ., hr)
.^lli.i ai char ntprl^l rol P. 28 ().!?
2.4 "C O.JH 0.? O.OOA
ft. 6 55 n.l« 1.11 0.057
:.«. ;o o M fl.32 0.036
;.2 is n 08^. o.7H n.2U
..»:
t «d ^v FIPA MC thud S ^frnnt hnlf c.ilch).
U o. . • -rP rr -
^ p
1.0
n.05?
0.47-5
0.216
I.7B
*
>,snn.s »iaw nL-re^se v sev«Ji: .ire <- ^r. t.
l! : tculal <• Pflsslun fjttfTS fcr ri-sljj^l "11 (nnhuwflon -tic, on avrrajte, a 1 urtrt Ion of fuel .ill grade anO sulfur content:
.r*<]f A .11: I 75 CS) • '». IK kp./il)1 llrer ll't'SI • Ih.'lo' g.i 1 ] ulocr S in I'K- w«iRht Z of nulfut In thr oil. This re Ut IDOSI.I]! IB
r-.iM.l on HI Individual tfsls jnd lias .1 cor r •»!.-« r I nn n>->l ' Ic lent rf D.»V
- ' '
.1 i nil-. i..i KI « ri(l(N)' ;ih N()j/lP rta1 - 7. • s'.HXX;'] utiprr N In Ihd vclghl X »> .utrcKen In Ihr cil. Foi replriual oils havlc(; high
OU.'j ui.|;.t.t 1) nurogpn ronlpnl. une 15 kg NO,/'.C lltpr (12(1 ]h HOj/lu'gsl) aa an rnlaRlon laciir.
-------
Boiler load cin *lso affeot paniculate emissions in units
firing No. 6 oil. At low load conditions, participate emissions
say be lowered by 30 to 40 percent from utility boilers and by as
much as 60 percent from small industrial and commercial units. Ho
significant paniculate reductions luive been notr:d at low loads
from boilers firing any of :hc lighter grades, however. At too low
a lend condition, proper combustion conditions cannot be maintained,
and yartieulate emissions may increase drastically. It should be
noted, in this regard, that any condition that prevents proper
boiler operation can result jn excessive particulate formation.
1 ™ S ') r 77
Sulfur Oxides (SOX) ~ ' '' - Total sulfur oxide emission? are
almost entirely dependent on the sulfur content of the fuel and are
not affected by boiler si::t« burner desisn, or grade of fuel being
fired. On the average, mcie than. 95 percent of the fuel sulfur is
emitted as S02, about i to 5 percent as S03 anJ about 1 to 3 percert
as particulate sulfates. Sulfur trioxide readily reacts with water
vapor (both in air and in flue gases) to form a sulfuric acid mis:.
1-11 14 17 23 n
Nitrogen Oxides (NOX) ' ' ' '"' - Two mechanisms form nitrogen
oxides, oxidation of fuelbcund nitrogen and thermal fixation of
the nitrogen in combustion .air. Fuel KOX are primarily n function
of the nitrogen content of the fuel and the available oxygen (on
the average, about 45 percent of the fuel nitrogen is converted to
NOXt but this rosy vary from 20 to 70 percent). Thermal NOX, on the
other hand, are largely a function of peak flame temperature and
available oxygen - factors which depend on boiler size, firing
configuration and operating practices.
Fuel nitrogen conversion is the moro important NOX forming
mechanism in residual oil boilers. Except in certain largp units
havirg unusually high peak flame temperatures, or ±-\ units firing a
low nitrogen residual oil, fuel NOX will (jeiierally account for over
!>0 percent of the total NOX. generared. Thermal fixation, on the
oth'ji hand, is tr.e dominant NOX fanning mechanism in units firing
distillate oj.ls, primarily oec.'use c-.f the negligible nitrogen
content in these lighter oils. Becau.se distillate oil fired boilers
usually have low heat release rate,i>, however, the quantity of
thermal NOX formed in them is less than that, of larger units.
A number of variables influence how much NOX is formed by
f:hes* -wo mechanisms. One important variable is firing configuration.
Nitrogen oxide emissions from tangentially (corner) fired boilers
are, on the average, less than those of horizontally jpposed units.
Also important are the firing practices employed during boiler
operation. Limited excess air firing, tlue gas reoircu]ation,
staged combustion, or some combination thereof may result in NO*
reductions from 5 to 60 percent. See Section 1.4 for a discussion
of these techniques. Load reduction can likewise decrease NOX
production. Nitrogen oxides enissiona may be reduced from 0.5 to 1
percent for each percentage reduction in load from full load operation.
It should be noted that most of these variables, with the1 exception
8/82 External Combustion Sources 1.3-3
-------
cf excess air, influence the NOX emissions only of large oil fired
boilers. Limited excess air Cirln£ is possible in many small
boi'i.ers, but the resulting NGX reductions are not nearly as significant,
I is2 i
Otl.er ljollutantu - Aa a rule, onl/ minor amounts of volatile
organic compounds (VOC) aad carbon monoxide will h-e emitted from
the combustion of fuel oil. The rate nt which VOCs are emitted
depends ou combustion efficiency. Emissions of trace elements from
oil fired builers ate relative to tht trace elenent concentrations
of the oil.
Organic compounds present in the tlue gas .streams of boilers
include aliphatic and aromatic hydrocarbons, esters, ethers, alcohols,
cnrbonyls, carboxyli.: r.cids and polycylic organic imtter. The last
includes all organic, matter having two or more benzene rinjjs.
Trace elements are also emitted from the combustion of fuel oil.
The quantity of trace elements emitted depends 0:1 combustion
temperature, fuel feed roe.dKioism and the composition of the fuel.
The temperature determines the degree of volatilization of specific
compound*; contained in the fuel. The fuel feed mt-chanism affects
thti separation of emissions Into bottom ash and fly ash.
If a boiler unit Is operated improperly CT is poorly raaintainpd,
lae concentrations of carbon monoxide and VUCs nay increase by .several
orders of magnitude.
1.3.3 Controls
The various control devices and/or techniques employed on
oil fired boilers depend on th« type of boiler and the pollutant
being controlled. All such controls may be classified into three
categories, boiler modification, fuel substitution and flue gas
cleaning.
Boiler Modification ' ' ' - Boiler rnodification includes
any physical change in the boiler apparatus itself or In its opera-
tion. Maintenance of the burner system, for example, is important
to assure proper ,'.tomization ;ind subsequent minimization of any
unburned combustib ier.. Periodic tuning is important in snail units
for maximum operating efficiency and emission control, particularly
of smoke and CU. Combustion modifications, such as limited excess
e.ir firing, flue ga.s recirculation, staged combustion and reduced
load operation, result in lowered NOX emissions in large facilities.
See Table 1..3-1 for specific rtductions possible through these
combustion modifications.
Fuel Substitution"' ' "'"" - Kuel substitution, the firing of
"cleaner" fuel oils, can substantially reduce emissions of a number
of pollutants. Lower sulfur oils, for inst-incu, will reduce SOX
in all boilers, regr.idless ot" size or type of unit or
1.3-4 EMISSION FACTORS
-------
grade of cil fired. Particulates generally will be reduced when a
lighter grade of oil is fired. Nitrogen oxide emissions will be
reduced by switching to either a distillate oil or a residual oil
with less nitrogen. The practice of fuel substitution, howevnr,
may he limited o> the ability of a given operation to fire a better
grade of oil and by the cost and availability thereof.
Flue Gas Cleaning "^ - Flue gas cleaning equipment genet illy
is employed only on large oil fired boilers. Mechanical collectors,
a prevalent typo of control device, are primarily useful in con-
trolling particulates generated during soot blowing, during upser.
conditions, or when a very dirty, heavy oil is fired, 'luring the^e
situations, high efficiency cyclonic collectors can effect uj. to 85
percent control of particulate. Under normal firing conditions or
when a clean oil is combusted, cyclonic collectors will not be nearly
as effective due to A high percentage of small particles (less "han
3 microns diameter) being emitted.
Sleet rot; tat ic precipitators are commonly used in oil fired power
plants. Olcisr precipitators which are also small precipitators
generally remove 40 to 60 percent of the participate matter emissions.
Due to the low ash content of the oil, greater collection efficiency
may not he required. Today, new or rebuilt electrostatic precipitators
have collection efficiencies of up to 90 percent.
Scrubbing systems have been installed on oil—fired boilers..
especially of late, to control both sulfur oxides and particulate.
Thes? systems can achieve S02 removal efficiencies of up to 90 to
95 percent and provide particulc.cc control efficiencies on the
order of 50 to 60 percent.
1. W. S. Smith, Atmospheric Emissions from Fuel Oil Combustion:
An Inventory iluide, 999-AP-2, U.I. Department of Health,
Education and Welfare, Cincinnati, OH, November 1962.
2. J. A. Uanielson (ed.), Air Pollution Engineering Manual, Second
Edition, AP-40, U.S. Environmental Protection Agency, Research
Triangle Paris NC, 1973. Out of Print.
3. A. Levy, et al., A Field Investigation of Emissionsfrom Fuel
Oil Combustion for Space _Heatin_g, API Bulletin 4099, Battelle
Columbus Laboratories, Columbia, OH, November 1971.
4. R. F,. Barrett, e_t_ al^, Fie Id Invest iga tion of Emissions from
Combustion Equipment for Space HeatuTg, EPA-R2-7!5 - ~B4a, U.S.
Environmental Protection Agency, Research Triangle Park, NC,
June 1973.
5. U. A. Cato, e t al. , Field Tea ting: Application -Ji' Combustion
Modif i caMons To Control Pollutant Emissions from I nc'_u_s trial
Boiltrs - PhaseI, EPA-650/2-74-078a, U.S. Environmental
Prr*ection Agency, Research Triangle Park, NC, October 1974.
8/82 Kxternal Combistton Sources 1.3-5
-------
6. G. A. Cato, et al., Field Testing: Application of Coc.bustion
Modifications; To Control Pollutant Emissions fvon Iidastrial
"Boilers- Phase IT, EPA-600/2-76-Q86a, U.S. Environmental
Protection Agency, Research Triangle Park, NC, April 1976.
7. Partlculate Emission Control Systems for Oil-Fired Boilers.
EPA-450/3-74-063, U.S. Environmental Protection Agency, Research
Triangle Park, NC, December 1974.
8. W. Bartok, et^al., Systematic FieldStudy of NQX Emission
ControlMethods for Utility Boilers. APTD-1163, U.S. Environmental
"Protection Agency, Research Triangle Park, NC, December 1971.
9. A. R. Crawford, et al . , Field Testing; Application of Combustion
Modifications To Control NOX Emissions from Utility Boilers,
EPA-650/2-74-066, U.S. Environmental Protection Agency, Research
Triangle Park, NC, June 1974.
10, J. F. Deffner, e£ al., Evaluation of Gulf Econojet Equipment with
Respect to Air Conservation, Repo't No. 731RC044, Gulf Research
and Development Company, Pittsburgh, PA, Decenber 18, 1972.
11. C. E. Blakeslee and H. E. Burbach, "Controlling NOX Emissions
from Steam Generators", Journal of the Air Pollution Control
Association, ^3_:37-42, January 1973.
12. C. W. Sicg.-nund, "Will Desulfurized Fuel Oils Help?", American
Society of Heating, Refrigerating and Air Conditioning Engineers
Journal, U_: 29-33, April 1969.
13. F. A. t;ovan, et al.. "Relationships of ParticuLare Emissions
Versus Partial to Full Load Operations for Utility-sized
Boilers", Proceedings of Third Annual Industrial Air Pollution
Control Conference, Knoxvillc, TN, March 29-30, 1973.
14. R. E. Hal", , _gt_al_._, A^ St_ady of Air Pol 1 u_tant Erniasions from
Residential Heating Systems, EPA-650/?--74-C03, U.S. Envl ronir.pnta!
Protection Agency, Research Triangle Park, NC, January 1974.
15. Flue Gas Desulfurization: Installations and Operations, u.S.
Environmental Protection Agency, Washington, DC, SepL^tiber
1974.
lb. Proceedings: Flue Gas DesulfurizationSymposium - 19/3.
EPA-650/2-73-038, U.S. Environmental Protection Agency, Research
Triangle Park, NC, December 1973.
17. R. J. Million, et a 1., Rjaview of NOX Emissior. Far.tors for
Stationary Fossil Fuel Combustion Sources, EPA-450/4-79-021,
U.S. Environmental Protection Agency, Research Triangle Kirk.
NC, September 1979.
1.3-6 EMISSION FACTORS 3/82
-------
Id. K. F. Suprenaut, et al., Emissions Assessment of Conventional
Stationary Combustion Systems: Volume I. Gas and Qil-Fired
Residential Heating Sources. EPA-600/7-79-029b, U.S. Environmental
Protection Agency, Research Triangle Park, NC, M.iy 1979.
19. C. C. Shih, et al., Emissions Assessment of Convent tonal
Stationary Combustion Systems: Volume III. External Combustlo'i
Sourcbs forElectricity Generation. EPA Contract No. 68-02-2197~,
TRW Inc., Redondo Beach, CA, November 1980.
20. N. F. Suprenant, eC al., Emissions Assessme-:.t of Conventional
Stationary CombustionSystems: Volume IV. Commercial
Institutional Combustion Sources. EPA Contract No. 68-02-2197,
GCA Corporation, Bedford, MA, October 1980.
21. N. F. Sup tenant, et ai^, Fjiiib signs Assessment of Conventional
Stationary Combustion Systems; Volume V. Industrial Combustion
Sources, EPA Contract No. •'8-01-2197, GCA Corporation, Bedford,
MA, October 1980.
22. Fossil Fuel Fired Indus trial Boiler^ - Background Information
for Proposed Standards (Draft EIS), Office of Air Quality
Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC, June 1980.
23. K. J. Lim, et al., Technology Assessment Report for Industrial
Boiler Applications: NOx Combustion Modification, EPA-600/ ~
7-79-l78f,U.S. Environmental Protection Agency, Research
Triangle Park, NC, December 1970.
24. Emission Test Reports, Docket No. OAQPS-78-l, Category II-I-257
through 265, U.S. Environmental Protection Agency, Research
Triangle Par);, N'C, 1972 through 1974.
25. Primary Sult'ate Emissions from Coal and Oil Combustion, Industrial
Environrnent.il Research Laboratory, U.S. Environmental Protect Jon
Agency, Research Triangle Park, NC, February 1980.
26. C. Leavitt, et al., Environmental Assessment of an Oil-Fjred
Controlled utility Boiler, EPA-600/7-80-087, U.S~Envlronmental
Protftctior. Agency, Research Triangle Park, NC, April 1980.
27. W. t>. Carter and R. -I. Tidinvi, Thirty-day Field Tests of
Ind viBtr 1 al Boilers : Site 2 __- Residual-oil-fired Boile.,
EPA-600/7-80-085b, U.S. Environmental Protection Agency,
Research Trian^Je Park, NC, April 1980.
28. G. R. Of;:en, et _a_.l_.. Co:itrnl of _Part.lctilate Matter from Oil
Burners .md Boilera, F?A-450/3-76-005, U.S. Environmental
Protecticn Agency, Research Triangle Park, NC, April 1976.
fl/82 External Combustion Sourcts 1.3-7
-------
1.4 NATURAL GAS COMBUSTION
1.4.1 General1'2
Natural gas is one of the major fuels used throughout the
country. It is used mainly for power generation, for industrial
process steam and heat production, and for domestic and commercial
space heating. The primary competent of natural gas is methane,
Although varying amounts of ethane and smaller amounts of nitrogen,
helium and carbon dioxide are also present. Gas processing plants
are required for recovery of liquefiable constituents and removal
of hydrogen sulfide (H2S) before the gas is used (see Natural Gas
Processing, Section 9.2). The average gross heating value of
natural gas is approximately 9350 xiloculories per standard cubic
meter (11)50 British thermal units/standard cubic foot), usually
varying from 8900 to 9800 kcal/scm (1000 to 1100 Btu/scf).
Because natural gas in its original state is a gaseous,
homogenous fluid, its combustion is simple and can be precisely
controlled. Common excess air rates range from 10 to 15 percent,
but some large units operate at lower excess air rates to increase
efficiency and reduce nitrogen oxide (NOX) emissions.
1.4.2 Emissions and Controls
Even though natural gas is considered to be a relatively clean
fuel, some emissions I-.JP occur from the combustion reaction. For
example, improper operating conditions, including poor mixing,
insufficient air, etc., may cause large amounts of smoke, carbon
monoxide and hydrocarbons to be produced. Moreover, because a
sulfur containing mercaptan is added to natural gas for detection
purposes, small amounts of sulfur oxides will also be produced in
the combustion process.
Nitrogen oxides art the major pollutants of concern when
burning natural gas. Nitrogen oxide emissions are functions of
combustion chamber temperature and combustion product cooling rate.
Emission levels vary considerably with the type and siz.e of unit
and with operating conditions.
In some: large boilers, several operating medificatlor.s rcay be
employed for NO control. Staged combustion for example, including
off-stoichiorr.etric firing and/or two stage combustion, can reduce
NO emission by 5 to 30 percent.^ jn off-stoichioi.ietrir firing,
also caller] "biased firing", some burners are operated flu.?! rich,
some fuel Itan, and others may supply air only. In two stage
combustion, the burners are operated fuel rich (by introducing only
70 tu 90 percent stoichiome.tric air), with combustion ocing completed
by air injected above the flame '/.one through second stage "NO-ports".
In staged combustion, NOX emissions arc reduced because the bulk of
combustion occurs under fuel rich conditions.
8/82 Kxternal Cr;mbu«;tion Sourcps
-------
Other NOX reducing mudific.itIons include low excess air firing
and flue gas recirculation. In low excess air firing, excess air
levels ace kept as low as possible without producing unacceptable
levels of unburned combustibles (carbon monoxide, volatile organic
compounds and suwke) and/or other operational problems. This
technique can rciduc*3 NOV emissions by 5 to 3j percent, primarily
because 01" lac*, of oxyi^n during combustion. Flue gas reelrculation
into the primary combustion /ore, because the flue gas is relatively
cool and oxygen deficient can also lower NOX emissions by 4 to
83 percent, depending on the amount of gas ruclrc.ulated. Flue gas
recirculation is best suite! for new boilers. Retrofit application
would require extensive burner modifications. Initial studies
indicate that low NOX burners (20 to 50 percent reduction) and
ammonia Injection (40 to 70 percent reduction) also offer NOX
emission reductions,
Combinations of the above combustion modifications may also be
employed to reduce NOX emissions further. In some boilers, for
instance, NOX reductions as high as 70 to 90 percent have been
produced by employing several of these techniques simultaneously.
In general, however, because the net effect of any of these
combinations varies greatly, It is difficult to predict what the
reductions will be in any given unit.
Emission factors for natural gas combustion are presented in
Table 1,4-1, arid factor ratings in Table 1.4-2.
1.2
40
Figura 1.4-1 Load reduction coefficient as function of boil-sr
load. (Usec! to determine NO* reductions at reduced loads in
large bo Her 3.)
1.4-2
EMISSION KACTOUS
3/82
-------
00
ho
it
E
TABLK 1.4-1. UNCONTROLLED KMISSION FACTORS FOR NATURAL CAS COMBUSTION3
Knrn.tr*' S17.V t* Typ*'
1 In*' niu/'hr
hi-.it input)
unlit- >T.I Irrs
Indus! ill hot It
Ik'TH-st If ami
I'Ji 'ilciil^tes' Sulfur
kR/U>''m ' ]b,'lo''|i( Ulixldr
i.f
7740 140
n f. i.h 1600 100
'•*
Nitrogen ' c;0 IS
320 JO
Volatllr OrK-tnUd
Nt>nrarlhane Hetham-
1.4
?.H
V)
«1
•..» 0.3
4H 1
7.7
O
O
3
O
3
O
c.
ft
r>
a
0)
"All ™1::-.
Hef »-t ences
Ke
rRr
r .
ir:n.r^ t->— in. f ^
rcnre 4 (bns'-d <-n dr aviT.iKf <>[jirnr content -jf natural ga> uf 4600 g/10 Na (20OO
>• rcnres 4-';. 7-0. ! 1,14. IH-19. 2 I.
r^ssrn ns Ni>7. Tf»ir rFsu1r
-------
.<,-.!. FAuPiR RATIMiS I'Oii NATURAL CAS CUMSiJSTJON
r :; j: t. > • « i r' v ' 'i c ^vs -;. " r ^ i' •
A \ A
A .\
1.' i- ill.1 1 ^: I >i' i;
1. II. M, llur,1 , o.t cil . , Exhaust O'ases f rom roir.bus L ipn and Industrial
tjses, K^A Contract No. KIIS1) 71-36, Engineering Science,
Inc., Washington, DC, October 2, 1971.
2, J. H. Hurry («?d.), Chemlca^ Fn^ineer 's Hirndbook , Ath Kilit:.o:,,
MtCr.iw-Hill, New York, NY, 196.3.
J. ti. H. H«wc:y, o_t _ >«_!_., Th:? 'jeyolopnunt of Air Cgnt-imtnanl F.Tnissioi
'1 ah L e s t o r No n-p r »_c^ .-;_« Kiui ss i o ns , New York State Department of
Hualtli," Arh.'ny. NY, 19o5.
•4. W. Harii'k, £t .Jl_. , Sy s i ujna_^L r Fjel d S t ud v ot'_ NOx Jmi ss ^on
r^> r.)1 Ni'MiatU for UtiHt>' !;.->ilt.'r.s, APTlJ-llh3, L.S. i^n^-Lrnn-
nw."i<.tl i'i i'( i-ct ion Aju'ncy, Kf-si-nrch Tr i.iri}'. Io Pa '< , N'C , Ut cemht'r
• ) 'i I .
•) . 1 , A . .V'...v.'l ', .'I ,(!., "Os. i'h's of Nitro^;*'!) KiTiis s i itn Ui-ducticu
!'r»i>'i.-in f»r (Ml .-ni'i '.a^ P.ri.'c! ;ItL!;ty iJo L Ic rs,", _l^iu_c o • ! • >hs j r i im
(.'•. ;i '()•].';" ion I'.i'iu i^ncn_t ' or _ b u L- HtM_t ing, KPA-U 2 •-,' 3—0 ;•••'», U.S.
Knvi ; L>iinii ;iu.l I'r ^; tec L i ->t» A;;. ,!'y, Rf.sc,i|-'::i Tr i .):ii'Ji.- 'ark, NO,
.June 1V/3.
PrivaLt corinkiii LCri t ion wi rl. the Awri'.in !.as Assuf i. it. i on
I.abi;ra Li^r i cs , CH'vt^lan-J , -;li, Mr: ll
-------
".0. Unpublished data on domestic gas fired units. National Air
Pollution Control Administration, U.a. Department of Health,
Education and Welfare, Cincinnati, OH, 1970.
11, C. E. Blakeslee arid H. E. Burbock, "Controlling NOX Emissions
from Steam Generators", Journal of the Air Pollution Control
Association, ^3_: 37-42, January 1979.
12. L. K. Jain, et_al_. . "S,t3te of the Art" _for Controlling N0>:
Emissions; Port 1, Utility BpilerR, EPA Contract No. 63-02-0241,
Catalytic, Inc., Charlotte, NC, September 1972.
13. J. W. Bradstrtet and R. J. Foreman, "Status of Control Techniques
for Achieving Compliance with Air Pollution Regulations by the
Electric Utility Industry", Presented at the 3rd Annual Industrial
Air Pollution Control Conference, Knoxville, "N, March 1973.
14. Study of Emissions of NOX from Nature! Gas-Fired Steam Electric
Power Plants in Texas, Phase II, Vol. 2, Radian Corporation,
Austin, TX, May 8, 1972.
15. N. F. Suprenant, e t a 1 . , Emissions Assessment of C
Stationary Combustion Sy^tems^ Volume I. Gas anci
Residential Heating Sources, EPA-600/7-?9-029b, U.S. Environ-
mental Protection Agency, Research Triangle 1'ark, NCJ, fay
1979.
16. C. C. Shin, et al . , Lmlssions Assessment o' Conv^nti jnal
Stationary Combustion Systems; Volume II ' . Ex :ern jl
Combustion Sources for Electricity Genctvcion, EPA Con*. rare
Nc. 60-02-2197, TKW, Inc., Redonco Beac'., CA, N'm'mbev I960.
17. N, F, Suprenant, et al . , Emissions As.1 • asmer.t of Cpaventloxial
Stationary Combustion Systems; Volurr.!? IV. C,'oT,mercial
Ins titut icinal Combus t Ion Sources, iP-T Contract No. 68-C2-2197,
GCA Corporation, Bedford, MA. Octobj: 198J.
Id. N. F. Suprenant, et al . , Erc...ssio.i;. Asse jsmo^t of Conventional
Stationary Combustion Systems; > < lume V. Industrial Combustiori
Sources, EPA Contiact No. 68-OT"2197, GCA Corpovntior , Bedford,"
HA, October 1980.
19. R. J. Millignii, et al . , Revi< /- of l',0\ Zmission Facto ra for
Staticnary Fossil Vuel CorobL'.v-ion Sources, EVA-^50/4-79-D21 ,
U.S. environmental Protect Jji Agen-.y, Research Triangle Park,
NC, f.evtember 1979.
20. W. }.. Thrasher and J. W. Diwertn, Evaluation of the Pollutant^
Emissions fi'on (ias-Flre- Vater Heaters, Research Report No.
L5
-------
21. W. li. Thrasher and I). W. Dewerth, Evalua t ion of the Po L lu t -ict
Emission^; frotu Gas-Fired Forced Air Furnaces, Research Reporf:
No. 1503, American Gas Association, Cleveland, OH, May 1975.
22. G, A. Cato, et al . , Field Testing: Application of Cotnbustirn
Modification To Control Pollutant Eials slons from Industrial
Boilers, Phase I, El5A-650/2-74-078a, U.S. Environmental Protection
Agency, Washington, DC, Ortobar 1974.
23. G. A. Cato, et al . , Field Testing: Appl ication of Co.ihustion
ModiE icition To Control Pollutant ETnisKions from
toilers, Phase II, EPA-60f>/2-7 6-OH6a, U.S. Environ™- ntal Pro-
tection Agency, Washington, DC, April 1976.
2'*. W. A. Carter and H. J. Buenlng, Thirty-ciay Field Ti.sts nf
Industrial Boilers - Site 3, EPA Contract No. 68-02-2645, KV)i
Engineering, Inc., frvine, CA, May 1981.
25. W. A. Carter and H. .1. Buening, Thirty— da;- Field Testa of
Industrial Boilers -. Site 6, EPA Contract No. 68-02-2645,
KVB Engineering, Inc., Irvine, CA, May 1981.
26. K. J, Lim, et al ._, Technology Assessment Report for Industrial
Boiler Applications: NOx Combustion Modification, EPA Contract
No. 68-02-3101, Acurex Corporation, Mountain View, CA, Decer.ber
1979.
1.4-6 EMISSION FACTORS 8/82
-------
1,5 LlgLFFILO PETROLEUM CAS COMBUSTION
1.5.1 General
Liquefied pctiToleum gas (T.PC) consist* ot butane, propane, or
a mixture of the two, and of trace amounts of propylene and btitylene.
This gas, obtained from oil or gas wells as a gasoline refining
byproduct, is sold as a liquid in metal cylinders under pressure
and, therefore, is often called bottled gas. LPG is graded according
to maximum vapor pressure, with Grade A being mostly butJne, Grade F
mostly propane, and Grades B through E being varying mixtures of
butane and propane. The heating value of LPG ranges from 6,43U
kcal/liter (97,400 Btu/gallon) for Grade A to 6,030 kcal/liter
(90,^00 Btu/gallc-n) fur Grade F, The largest market for LPG 1 ' hr
domcistic/commercial market, followed by the chemical industry «•-.-
the internal combustun engine.
1.5(2 Emissions
LPG is considered a "clean" fuel because it does not produce
visible emissions. However, gaseous pollutants such as <:arbon
monoxide, volatile organic compounds (VOC's) and nitrogen oxides do
occur. The most significant factors affecting these emissions are
burner design, adjustment and venting. Improper design, blocking
and clogging of the flue vent, and lack of combustion alv result in
improper combustion and the emission of aldehydes, carbon monoxide,
hydrocarbons and other organics. Nitrogen oxide emissions are a
function ?f a number of variables including temperature, excess
qir and lesidenefe t">'.ift i.i the con.-bustion zone. The arnouit of
f.ulfiH dii'X'.de emitted Is directly proportional to the ajiount of
sulfur in hi fueli Eiiiss'on factors for LPG combustion are presented
in table J.V-l.
8/62 Cxisernal Combustion Sources 1.5-1
-------
TARLF. 1.5-1. EMISSION FACTORS FOR LPG COMBUSTION3
EMISSION FACTOR RATING: C
S'i]-"V Nftroi^pn T^riur Volatile O'^.inlfs
^ 1,1,1,|..I r, ll
O K»t PI.- 'Mil O.Mh •?. |M:I.-.' 'l.i)l' fi.OfS I.SI 11.7 u.4 I.I O.nj O.20 O.U3 0.2H
Z l-ri-r-inr n.ii] :).!)', i..n.dt5 !.'••) 12.'- (}.'.! «. I :'.'»! «.2^ O.in ;>.,';
n^
^ (''irv I )• /
p Bul.mt ii.lll--( .(Hi II.I" I!.'.' Ii.(IIS O.I)1)' i.ll 9.4 D.'^i I." O.IMi 0. S O.dl <)./•)
S l'i.,,nnr .|.:II-I.IIK n.iiM-u ( •. ii.c.|' ').If 1. II') B.8 0. .'2 I.H n.0*i d.«7 0.01 (1.^4
AHV imr- rT\;sJ.'r'. ic*.-rpT siil'iir 'Xltl'"O "r« |i|»' ^.um-, .m n h •;!! :»pul Imsis, *«; for nalt|-.T' H.TS comhii^llon.
Ihr- I'.ilj .T.)-;-I-'I-. f-icli-i uc.iil,! !,«• 'i.ill : ". Ih'. m n.uM> t,; S.'lj/lll' lli-rrfi (O.fN « (I. l(, or 0.014 Ib o! SO,/HH)I! ,•.>!) hjt.inM I.Kinf.i.
3D
-------
References for Section 1.5
1. Air Pol tut ant Emission Factors, Pinal Report, Contract No.
CPA-22-69-119, Resources Research, Inc., Reston, VA, Durham,
NC, April 197U.
2. E. A. Clifford, A Practical Guide to Liquified Petroleum Gas
L'til Lzation. New York, Moore Publishing Co., 1962.
8/8." External Combust urn Sources 1.5-3
-------
l.b WOOD WASTK COMBUSTION IN BOILERS
1. 6. i Cpn^r.i i
The burning of wcu>d waste in boilers is most!" confined to
those industries where il is available as a byproduct. It is
burned both i<.' obt.iin ht.it energy and to alleviate possible solid
waste disposal problems. V.uod waste may include large pieces like
slabs, lo^s and hark strips ;js well n.s cuttings, shavings, pellets
and sawdust, anJ heating values for this waste muge from about
4,401) to 5,000 xiloc.il cries per kilogram of tuel dry weight (7,9-^0 to
9,131 Btu/lb). However, because of typical moisture contents of
4(J to 1'j percent, the healing valut.-s for many wood waste materials
as fired range as low as 2,200 to 3,300 kileealoric-s per kilogram
of fuel. Generally, bark tt; the major type cf waste burned in palp
mills, and ,1 varying mixture of wood and bark waste, jr wood waste
alone, are most frequently burned in the lumber, furniture and
plywood industries.
1-"}
1.6.2 Firing i radices
A variety of boiler firing conl igu>. aliens i.s used for burning
wood waste. One common type in smaller operations it, the dutch
oven, or extension type of furnace with a flat grate. This unit is
widely used because it can burn fuels with a very high moisture
content. Fuel is ted into the oven through apertures at the top of
a firebox ana i:> fired in a cone shaped pile on a flat grate. The
burning is done; in two stages, drying and gas i filiation, and combustion
of pv>,senus products. Tht r:rst stage takes place in a cell separated
from the boiler section bv a bridge wall. The combustion stap,e
takes place in the m.iin boiler section. The dutch oven is not
responsive to changes v steam lo-i-i, and it niovidts poor conli-ustion
control.
In a fuel cell oven, the fuel is dropped onto suspended f .xed
grate:; and is fired in a pile. 'Jnliku the uutch ^>ver>, IN-' fuel
cell .ilso u'j <:-•'• cambustlon air preheating and reposit'i ouia^ o^ the
secondary and tertiary air injection ports to improve bo HIT >2f f ici>'ncy,
in many large nporat iont-, more coT'vent ional boilers liavti been
n\odified tr burn wood waste. T^r,-,^ units may include .spreader
stokers with tra/cljn^ giates, vibrating grate stokers, etc., as
well =s t^p.fint i.ally fired _>r cyclone f-.red h,>ilerri. '"he most
wia«Ly used of these conf i.guvations is the sprtacJor sc-iker. Fuel
LH dropped ir front of :\n flit j
-------
supply fluctuates and/or to provide more steam than is possible
from the waste supply alone.
Sander dust is often burned in various boiler types at plywood,
particle board and furniture plants. Sander dust contains fine
wood particles with low moisture content (less than 20 weight
percent). It is fiied in a flaming horizontal torch, usually w'th
natural gas ds an ignition aid or supplementary futl.
/ *} U
1.6.3 Emitilous and Controls
The major pollutant of concern from wood boilers is partic-jlate
matter, although other pollutants, particularly carbon monoxide,
may he emitted in significant amounts under poor operating conditions,
Thrise emissions depend on \ number of variables, including (1) the
composition of the waste fuel burned, (2) cne degree of flyash
reinjection employed and (3) furn--.c3 design and operating conditions.
The composition of wood wastj depends largely on the industry
whence it originates. Pulping operations, for example, produce
great quantities of bark that may contain more than 70 weight
percent moisture and sand and other noncombustibles. Because of
this, bark boilers in pulp mills may emit considerable amounts or
particulate matter to the atmosphere unless they are well controlled.
On the other hand, some operations such as furniture manufacture
produce a clean dry (!> to 50 weight percent moisture) wood waste
that results in relatively few particulate emissions when properly
burned. Still other operations, such as sawmills, burn a variable
zlxtare of bark and wood waste that results in particulate emissions
somewhere between these two extremes.
Furnace design and operating conJitlons are particularly
important when firing wood waste. For example, because of the high
moisture content that can bo present in this waste, a larger than
usual area of refractory surface is cften necessary to dry the fuel
before combustion. In addition, sufficient secondary air must be
supplied over the fuel bed to barn r.he volatiles th>n account for
most of the conbustible material in the waste. When proper drying
conditions do not exist, or when secondary combustion is incomplete,
the combustion temperature is lowered, and increased particulate,
carbon monoxiile and hydrocarbon emissions may result, lowering of
combustion temperature generally results in decreased nitrogen
oxide emissions. Also, emissions can fluctuate in the short term
due to significant var •-3 Lions in fuel moisture content over short
periods of time.
Flyash rsinjecticn, which is common in many larger boilers to
improve fuel efficiency, has H considerable efftct on particulAte
emissions. Because a frartton of the collected flyash is riiinje.cted
into tn^ boiler, the. dust loading from ',h
-------
00
NJ
TABLE 1.6-1. EMISSION FACTORS FOR WOOD AND BARK COMBUSTION LN BOILERS
ih
T«in]ectlon locreajea the -ojd l.i to 2 t! aee v.th»jt
relnlcct loi.
*laied oc (uel a»l>turt> content o< 331.
'tiled an large d'jtch OSJ-B and spreadf r atuken taverafln^
23,^10 ki iteu/hr) vith ateaai pressures .m 20 - TJ ipa
,:',0 - iJO p«J).
Slated on imall dutch nvrns and iprraeer stokeri (utoally
opi rating <9074 kg steav/hr), irlth prrjaurei from 5-30 kpa
(31 - 110 pit). Caieful air adJuatKnta and laprov.d luel
• epAraLlon «•*! firing were Lj«d on ooate Ljnltn, but the
«fffcta car,not b« Isolated.
hRefiTercm 12-13 1? 11. Uncvi wnnrv Includtl cuttlngn,
ahavlnav, flawduBt bnc chlp», *rm/br} in Ncy Yurk unil Kortn Carolina.
iNefrrpncr 23. Baaed on laati. of (uel sullur content and
aulfur dloxld« aaliai^iui at (our mill* burolnc bark. The
limvr Hall of the range (fn par*nth*aea) ahAuld \tt uaed for
vood, and hl^htT valurn for hprk A hearlr^; value of 5000
kc«l/kg (9DOO ITU/lb} IK niauwd. The factora are baaed on
rhr dry iHlght uf fuel.
ka>fer«i>c»a 7, 24-2b- St-ofrnJ facto™ can Influence «1»iion
rates. Including roabuirinn tore reaperarurea, «xceaa alt,
boiler uperatlng coiu41tlnna. fuel wiliture and fuel nitrogen
coriteni. Factors on a dry Height baslt-
•*«f«r*nc. 30. Factora oo a dry velght baala.
"KvfvraiiClia 20, 30. Hct«eth«nc VOC raportedly canalara of
coapoucifai wll.l a high ^apor preaiore aurh aa alpha plnao«.
P^aferenee 3O. Baaad on an approxlaatIon of awthaoa/noa-
•ethanr ratio. «fclch It »ry varlabli- Ma than*, vapresaad aa
a Z of total «olatllt oiganlc coapo'^ids, varlad fro* 0 - 74
Ml^ht X.
-------
a tenfold increase in the dust loadings of some systems, although
increases of 1.2 to 2 times are i:iort- Lypical for boilers using 50
to 100 percent reinjection. A major factor affecting this duet
loading increase is the extent to which the sand and other noncom-
bustibles can successfully be separated from the flyash before
reinfection to the furnace.
Although reinjectLon increases boiler efficiency from 1 to
4 percent and minimizes the emissions of uncoinbusted carbor., it
also increases boiler maintenance requirements, decreases average
fTyash particle size and makes collection more difficult. Properly
designed reinjection systems should separate sand and char from the
exhaust gases, to reinject the larger carbon particles to the
furnace and to divert the fine sand particles to the ash disposal
system.
Several factors can influence emissions, such as boiler size
and type, design features*, age, load factors, wood spscies and
operating procedures. In addition, wood is often ^ofired with
other fuels. The effect cL these factors on emissions is difficult
to quantify. It is best to refer to the references for further
information.
The use of multitube cyclone mechanical collectors provides
the particulate control for many hogged hollers. Usually, two
multIcyclones are used in series, allowing the first collector to
remove the bulk of the dust and the socond collector to remove
smaller particles. The collection efficiency for this arrangement
is from 65 to 95 percent. Low pressure drop scrubbers and fabric
filters have been used extensively for many years. On the West
Coast, pulse jet3 have bcon used.
Emission factors for wood waste boilers are presented in
Table 1.6-1.
References for Section 1.6
1. jSteam, 38th Edition, Babcock and Wilcox, New York, NY, 1972.
2. Atmospheric Emissions from the Pulp and Paper Manufacturing
Industry, EPA-45Q/1-73-002, U.S. Environmental Protection
Agency, Research Triangle Park, NC, September 1973.
3. C-E Hark Burning Boilers, C-E Industrial Boiler Operations,
Combustion Engineering, Inc., Windsor, CT, 1973.
4. A. Barron, Jr., "Studies on the Collection of Bark Char throughout
the Industry", Journal of the Technical Association of the Pulp
ar.d_Pap_er Indus try, _53£8_)_: 1441-1448, August 1970.
5. H. Kreisinger, "Combustion of Wood Waste Fuels", Mechanical
Engineering, £Jj 115-120, February 1939.
1.6-4 EMISSION FACTORS 8/82
-------
6. Air Pollution Handbook. P.L. Magill (ed.). McGraw-Hill Book
Co., New fork, NY, 1956.
7. Air Pollutant Emission Factors, HEW Contract No. CPA-7.2-69-119,
Resources Research, Inc., Reston, VA, April 1970.
8. J.F. Mullen, A Method for Determining Combustible Losa, Dust
Emissions, .and Recirculated^ Refuse for a Solid Fuel Burning
SyBtem, Combustion Engineering, Inc,, Windso/:, CT, 1966.
9. Source teat data, Alan Lindsey, U.S. Environmental Protection
Agency, Atlanta, GA, May 1973.
10. H.K. Effenberger, et al., "Control of Hogged Fuel Boiler
Emissions: A Case History", Journal of the Technical Associa-
tion of the Pulp and Paper Industry, 56(2);111-115,
February 1973.
11. Source test data, Oregon Department of Environmental Quality,
Portland, OR, May 1973.
12. Source test data, Illinois Environmental Protection Agency,
Springfield, IL, June 1973.
13, J.A. Daniel son (ed.). Air Pollution Engineering Manual (2nd Ed.),
AP-40, U.S. Environmental Protection Agency, Research Triangle
Park, NC, 1973. Out of Print.
14. H. Drof.ge and G. Lee, "The Use of Gas Sampling and Analysis
for the Evaluation oE Teepee Burners", presented at the Seventh
Conference on the Methods in Air Pollution Studies, ;,O3 Augeles,
CA, January 1967.
Ib. U.C. Junge and K. Kwan, "An Investigation of the Chemically
Reactive Constituents of Atmospheric Emissions from Hog-Fuel
Boilers in Oregon", Paper No. 73-AP-21, presented at the Annual
Meeting of the Pacific Northwest International Section of. the
Air Pollution Control Association, November 1973
16. S.F. Galeano and K.M. Leopold, "A Survey of Emissions of
Nitrogen Oxides in th~. Pulp Mill", Journal of the Technical
Association of the Pulp and Paper Industry, 56(3)!74-76,
March 1973.
17. P.B. Bosserman, "Wood Waste Boiler Emissions in Oregon State",
Paper No. 76-AP-23, presented at the Annual Meeting of the
Pacific Northwest International Section ol the Air Pollution
Control Association, September 1976.
18. Source test data, Oregon Department of Environmental Quality,
Portland, OR, September 197fi.
External Combustion Sources 1.6-5
-------
19. Source test data, New York State Department of Environmental
Conservation, Albany, Nf, May 1974.
20. P.B. Bcsserrnan, "Hydrocarbon Emissions from Wood Fired Boilers",
Paper No. 77-AP-22, presented at the Annual Neeting of the
Pacific Northwest International Section of the Air Pollution
Control Association, November 1977.
21. Control of Particulate Emissions from Wood Fired Boilers,
EPA-340/1-77-026, U.S. Environmental Protection Agency,"
Washington, DC, 1978.
22. Wood Residue FiredSteam Generator Particular Matter Control
Technology Assessment, EPA-450/2-78-044, U.S. Environmental
Protection Agency, Research Triangle Park, NC, October 1978.
23. H.S. Oglesby and R.O. Blosser, "Infomation on the Sulfur
Content of Bark and Its Contribution to S02 Emissions When
Burned as a Fuel", Journal of the Air Pollution Control
Association. 30(7):769-772. July 1980.
24, A Study of Nitrogen Oxides Emissions from Wood Residue Boilers,
Technical Bulletin No. 102, National Council of the Paper
Industry for Air and Str«ara Improvement, New York, NY,
November 197S.
25. R.A. (tester, Nitrogen Oxide Emissions^ from a Pilot Plant
Spreader Stoker Bark Fired Boiler, Department of Civil
Engineering, University of Washington, Seattle, WA,
December 1979.
26. A. Nunn, NOx Emission Factors fur Wood Firgd Boilers.
EPA-600/7-79-219, U.S. Environmental. Protection .'.oency,
Research Triangle Park, NC, September 1979.
27. C.R. Sanborn, Evaluation of Wood Fired Boilert) and Wide Bodied
Cyclones in the State of Vermont, U.S. Environmental Protection
Agency, Boston, MA, March 1979.
28. Source test data, North Carolina Department of Natural Resources
and Community Development, Raleigh, NC, June 1981.
29. Nonfosail Fueled Boilets - Emission Test Report; Weyerhaeuser
C omp any, I c ng v i ew. Wash in g t o n. EPA-80-WFB-10, U.S. Environmental
Protection Agency, Office of Air Quality Planning and Standards,
Research Triangle Park, NC, March 19M.
J U. A Study of Wood-Residue Fi.re_d Power Bpilar Total Gaseous
Non-ietnane_ OrganicEmissions in the Pacific Northwest, Technical
Bulletin No. 109, National Council of the Paper Industry for Air
and Stream Improvement:, New York, NY, September 1980.
1.6-6 EMISSION FACTORS 8/82
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1.7 LIGNITE CCJM3US1IUN
1-4
1.7.1 General
Lignite is a relatively young coal with properties intermediate
to those of bituminous coal aiid peat. It has a high moisture
content (35 to 40 weight percent) ar>d a low wet busiR heating value
(15UU to 1900 kiloc ilories) and generally is burned only close to
where it is nined, .In sone midweftern States and in Texas. Although
a small amount is us-ed *n industrial and domestic situations,
lignite is mainly us-?d for s-.earn/electtic production in power
plants. In the past, lignite was burnwi mainly in small stokers,
but tod« with bituminous coal. There are
several reasons for this. First, the higher moisture content means
that more energy is lost in thu gaseous products of combustion,
which reduces boiler efficiency. Second, more energy is required
to grind lignite to the combustion specified size, especially in
pulverized coal fired units. Third, greater tube spacing and
additional soot blowing are required because of the higher ash
fouling tendencies. Fourth, because of its lower heating value,
more fuel r.uot be handled to produce a given amount of power, since
lignite usually is not cleaned or dried before ccmbustion (except
for gone drying that may occur in the crusher or pulverizer and
during transftr to the burner). Generally, no major problems exist
with the handling or combustion of lignite when its unique
characteristics are taken into account.
°—1 I
1.7.2 Emissions and Controls'"
The major pollutants of concern when firing lignite, as with
any coal, are particulates, sulfur oxides, and nitrogen oxides.
Volatile organic compound (VOC) and carbon monoxide emissions are
quite lrw under normal operating conditions.
ParLiculate K,i.,.sii'a levels appear mjst dependent on the
firing conl'lgurarovs in the boiler. Pulverized coal fired units
and spreader .';l./--r.-;, which fire .".11 or much of the lignite in
suspension, ^-nit the greatest quantity of flyash per unit of fuel
burned. Cyclones, which Collect much of the ash .as inolttn slag in
the furnace itself, arid stokers (ot',i<.;r than spreader), which retain
a la.t',e fuctiivi .if the ash in the fuel bed, both eaiit '.ess participate
matter. I:; gcut.ral, the relatively high sodiun conteut cf lignite
lowers partic:iiate emissions by causing more of tie resulting
flyash to deposit on the boiler tubea. This is especially ao in
pulverized coal fired units wherein i tiigh fraction cf thb ash is
8/82 External Combustion Sources 1.7-1
-------
TABLE 1.7-1. EMISSION FACTORS FOR EXTERNAL COMBUSTION OF LIGNITE CGALJ
v.
on
O
C
Firing Configuration
Pulverized Coal Fired
Dry Bottcai
Cvclone Furnace
Spreader Stoker
Other Stcktrs
Partlculataa Sulfur c Mltrogan Carbon VOC
dioxide oxldea Monoxide NoiMethane Methane
kg/Kg
3.1A
3.3A
3.4A
1.5A
Ib/ton kg/Mg
6.3A 15S
6.7* 15S
6. 8A 13S
2.9A 15S
Ib/tna kg/Kg Ib/ton
JOS 6e'f I2*lf g g g
MS 8.5 17 g g g
MS 3 6 g e g
JOS 3 6 g g g
. For uncontrolled anlisiooB, «nJ ihould be applied to lignite conaunptloa aa fired.
"Reference!, i-b.9,12. A la the wet baaia percent ash content of the lignite.
^References 2,%-b. S is the net bee IB purcent sulfur content of the lignite by weight. For a high aodiiui/aah lignite
(Na20 ^81), use H.W kg/Ha (17S Ib/ton); for a IS kg/Mg (]<>S Ib/ton). The conversion of sulfur to sulfur dlOactors reported In Table 1.1-1 nay be uaad, baaed on the similarity ot lignite coaibuatJoD and bltuBlooua coal coobuatlon
so
00
-------
suspended in the •ombustion gases r.nd can readily come into contact
with the boiler surfaces.
Nitrogen oxi.de emissions are mainly i*. function of the boiler
firing configuration and excess air. Stu'ittrs produce tha lowest fiU
levels, r^inly because most existing units are much smaller than
the other firing type and have lower pea'c f'.arae temperatures. In
most boilers, regardless of firing configuration, lover excess air
during combustion results in lower NO emissions.
Sulfur oxide t-.r.i ss ions are a function ot: thy alkali (especially
Sudl'jm) content of lha lignite ash. Unlike most, rossil fuel
combustion, in which over 90 percent of the fuel aultur is emitted
as S0a, A significant fraction of the sulfur in lignite reacts with
the ash conpone.it •» during combustion and is retained in th« boiler
ash deposits and :lyash. Tests have shown that less than 5J percent
of the available yulfur may be emitted as S02 when a high sodiun
lignite is burned, whereas more than 90 percent nay be emitted from
low sudiura lignite. As a rough average, about 75 percent of the
fuel sulfur will jr. emitted aa S02l the remainder being converted
co various sultat^ salts.
Newer lig-iite fired utility boilers are equipped with large
electrostatic precipitators that may achieve as high as 99.5 percent
p-trticulate control. Older and smaller electrostatic precipif.ators
operate at about 95 percent efficiency. Older industrial and
commercial units use cyclone collectors that normally achieve 60 to
8.1 percent collection efficiency on lignite flyash. Flue gas
1 furization systems currently are in jperation on several
e fired utility boilers. Thestj systems are identical to
v.hos< used on bituminous coal fired boilers (see Section l.l;.
Nitvogen oxide reducHons of up to 40 percent ca': ho achieved
by changing the burner geometry, controlling excess K~r ind iiwk.lng
ocher c'nang^s in operating procedures. The techniques are li;-'.nttcal
j'or biturnino.'g and lignite coal.
TABLE 1.7-2. RATINGS OF EMISSION
FACTORS FOK LIGNITE COMBUSTION
Firing Configuration
Fulveriied Coal Fired
Dry Bottom
Cyclone Fur.iace
Spreader Stoker
Other Stokers
Parriculates
A
C
B
B
Sulfur
Dioxide
A
A
B
c
Nitrogen
Dioxids
A
A
C
D
8/82 ^xt^rna] Combustion Sources 1.7-3
-------
Emission factors for p;»rticulates, sulfur dioxide and nitrogen
oxides are presented in Tab^e 1.7-1. Based on the similarity of
lignite combustion and ftiti riinous coal combustion, emission factors
for carbon monoxide ami volatile organic compounds reported in
Table 1.1-1 may be used.
Referencej fur Section 1.7
1. Kirk-Othmer Encyclopedia of Che.niic^l Technology, Volume 12,
Second Kdltion, .'ohn Wiley .-.nJ So'ns, New York, NY. 1967.
'L . u.H. Gronhovd, jt al_. , "So.rc.' Studies on Stack Emissions from
Lignltr Ftred Powerplantri", Presented -it the 1973 Lignite
Symposium, Grand Forks, Nl>, May 1973.
3. Standards Support and Fnvironmental Impact _ Statement i
Promulgated Standards of Performance for Lignite Fired S* eam
Generators : Volume.*; I and II , EPA-45072-76-030a,b. U.S.
Environmental Protection Agency, Research Triangle Park, NC,
December 1976.
4. 1965 Keystone Coal Buyers Manual, McGraw-Hill, Inc.. New York,
NY, 1965.
5. Source test data on lignite fired power plants, North Dakota
State Department of Health, Bismarck, NP, December 1973.
t>. G.H. Cronhovd, e t al . , "Comparison of Ash Fouling Tendencies
of High and Low Sodiu-n I. Ignite from a North Dakota Mine",
Proceedings of the American Power Conference, Vilume XXVIII,
1966.
7. A.R. Crawford, e t a 1 . , Field Test iajji Application uf Combustiun
Modification To Control NO Emisajons from Ulil
-------
11. C.C. Shih, et al_., Emissions Assessment of Conventional
Stationary Combustion Systems, Volume III! External
Combustion Sources for Electricity Generation, EPA Contract
No. 68-02-2197, TRW Inc., Redondo Beach, CA, November 1980.
12. Source test data on lignite fired cyclone boilers, North Dakota
State Departrcnt of Health, Bisraarck, ND, March 1982.
8/82 External CombuBtion Sources 1.7-5
-------
l.B BAGASSE COMBl STW> IN SI CAR MILLS
1.8.1 General1
Hagasse is (he fibrous residue from sugar rane thai has been processed in a sugar mill. (See Section
6. 12 for a h riff ge n.-ral description of sugar cane proct s-,ing ) It i> lirerl in hoi ler-< to eliminate a large
solid waste disposal problem and to produce slenm and r*le< Iriritx to meet th»» mill's power require-
ments. Bagasse represents about 30 percent of the weight n1 tin- raw sugar cane. Because of t he high
moisture content (usually at least 30 percent. by weigr.i) a tvpical hen ing value of wet hagas..e will
ran ^f from ;100G to 4000 Blu/lh (1660 to 2220 kcul 'kg). Fuel oil may be fired with bagasse when the
inillVpower requirement • ran no I be met liv buriiiii^ only l>d|tasxr or whf n bagasse is too wet to sup port
eumlnisliun.
The I'niled Stales sujjur industry is loeulcd in Muridn. Louisiana. Hawaii. Texa>, and I'nerl') H;co.
l,xce[jl in Hawaii, where raw su^ai prudiu lion lakes plate year round, sugar mills operate seasonally.
from 2 lo 5 months per year.
lia^asse is common I \ fired in builers empluy ing eil her a solid hearth or Iraxclin^ prate. In the for-
mer, hagasse is prat ily fed through chutes and forms a pile of burning filters. The burning occur* on
the surface of the pile with combustion air supplu . ihronph primary and second dry ports located in
the furnace walls. This kind of boiler is common in older mills in the sugar i ane iiidusl ry. Newer boil-
ers, on the other hand, may employ Iraselin^-grate ankers. I ndi-rfire air is used to suspend the h.i-
passe, and o\erfired air is supplied t o complete comb • >sl ion. This ki nil of boiler require* bagasse wilh;i
higher percentage of fine*, a moisture content not over 50 percent, and more expeiienced operating
personnel.
1.8.2 Kmissions and Control* '
Par ti< n late is the major pollutant of concern from itagii^se boilers. I 11 1 ess an aii\ilir.ry fuel is fired,
few sulfur oxides u ill be emitted because of the low siilfu-- contrni i<0 I perient.hy weight) of lia-
Kas.-e. Some nitrogen oxides a re emitted, alt hough the ijuan lilies appear ti> he somewhat lower (on an
(.•qunaleut heal input hasis) than are emitted from conventional fo -il i'uel boilers.
Paniculate emissions are reduced by the n.-c of mul'i-i yeloiu's and ,»el scruhhers. Vli.Mi-c
are reported I \ 20 to 60 percent efficient on parliiulalc (r,m hagasso boilers. whereas-t.'iiliiri or the spray impingement t\ pe) are usually 90 percent or more efficient. Oll.cr <\ pe< of ci,':-
I rol ei|uipnienl have been investigated hut ha\o not been found to )>r priiriii'i!
F..ni>sior. luclors for bagassr fired boilers ure shown in Table J.H-1.
1/77 Kxlrrnal ( onilMislioit
-------
Table 1.8-1. EMISSION FACTORS FOR UNCONTROLLED SAGASSt BOILERS
EMISSION FACTOR RATING C
' lb/103 Ib steam -
ParTiculatec
Sulfur oxides
Niuocen oxides6
4
d
0.3
Emis
y/K-j blearri3
sion factors.
'u/ton bago-iM1*5 | kp/MT bagasse1*
4 { 1H
d
0.3
d
1.2
8
d
O.r,
tartofs are expressed in terms r.i rue amount of steam pmrluc.'rt, ai most mills do no! monitor The
"mount of t-agasse f if«d These factors should be applied only (u lhat fraction u! stpam resulting from bagasse
cnnhusiir •! I) a s gniticant amount (> 25% of total Btu input) c* fuel oil is f ued mc .,? pen-em adriicuiatu control.
cuJgte : on- baqajsc boilers. vVei sc
Based on deference 1
^SuH jr oxide cmisj-ons frum the firing of l^sgaue alone mauiil be expected to be negho,bi« as bagasse typically
coniHitu less than 0.1 percent sulfur, by weight. If fuel oil is f red with bagassf . the appropriate factors from
Table 1 3-1 should be used to esumitr sulfur uxi Jr emissions
* Based on Reference 1
for So<-lioif l.H
Background Document: Hapuxie ('omlu;>lion in Siijiiir Mill.s. Pn-purvd h\ F'.in ironniciit.il Srh-nct-
and Kniiinefrinit. Inc.. Gainps\ illc. Fla.. for f.n\ ironmrnlal Pi. •.!:•: HDD AJJOIICV nnrlcr ('.(inlrarl
No. 6H-02-I402. Tu.-k Ordi-r No. 1.1. Dociimt-nt No. KI'A-JoO ,',-77-(MI7. H«>«-arch Triangle Park.N.C.
Orldhcr 1976.
KXCTUHS
1/77
-------
1.9 RESIDENTIAL FIREPLACES
1,9.1 General1"2
tireplaces are used mainly in homes, lodges, etc., for supplemental
heating and fur aesthetic effects. Wood is the most common fuei far
fireplaces, but, coal, compacted wood waste "logs", paper and rubbish may
also bt burned. Fuel is intermittently added to the f ire. by hand.
can be divided into two broad categories, 1) masonry,
generally brick fireplaces, assembled on site integral to a structure and
2) prefabricated, usually rietal, fireplaces installed on site, as n package
with appropriate ductwork.
Masonry fireplaces typically have large fixed openings to the firehed
and dampers above the combustion area in the chimney to limit room air and
heat losses when the fireplace is not being used. Some masonry fireplaces
are designed or retrofitted with dooro and louvers to reduce thf intake of
combustion air during use.
Many varieties of prefabricated fireplaces are now available on the
market. One general class is the freestanding fireplace. The most common
freestanding fireplace models consist of an inverted sheet metal funnel and
stovepipe directly above the fire Sed. Another class is the "zero clearance"
fireplace, ar. iron or heavy gauge steel firebox lined with firebrick on the
inside and surrounded fcj* multiple, steel walls spaced for air circulation.
Zero clearance fireplaces Cc-ii be inserted into existing masonry fireplace
openings, thut; they are sometimes called "inserts". Some of these units are
equipped wi t'l close fitting doors and have operating and combustion character-
istics similar to wuod stoves (see Section 1.10, Residential Wood Stoves).
Prefabricated fireplaces are commonly equipped with louvers and glass doors
to reduce the intake cf combustion air, and some are surrounded by ducts
through which floor level air is drawn by natural convection and is heated
and returned to the room.
Masonry fireplaces usually heat ,1 room by radiation, with a significant
fraction of thtj combustion he«'t lost An th* exhaust gases or through the
fireplace walls. Moreover, some of the radiant heat entering the room must
go toward warming the air that is pulled into the residence to make up for
tlit air drawn up the chimney. The net effect is that masonry fireplaces are
usually inefficient heating devices. Indeed, in cases where combustion is
poor, where the outside air is cold, or where the fire is allowed to smolder
(thus drawing air into a residence without producing appreciable radiant
heat energy), a net heat loss nay occur in a residence from usn of a fireplace.
Fireplace heating efficiency iray te improved by a number of measures that
either reduce the excess air rate. or transfer some of the heat back into the
residence that would normally be lost in the exhaust gases cr through the
fireplace- walls. As noted above, such measures are comnonly incorporated
into prefabricated units. As a result, the energy efficiencies of prefabri-
cated fireplaces are slightly higher than those of masonry fireplaces.
5/83 External Combustion Sources 1.9-1
-------
1.9.2 Kmissions
The major pollutants of concern irons fireplaces are unburnt combustibles,
including carbnn ir.unoxlde, gaseous organics and particulatt matter (i.e.,
smoke). SiguifLeant quantities of unburnt combustibles are produced because
fireplaces are ?.uet:ficient combustion devices, because of high uncontrolled
excess air rates and the absence of any sort of secondary combustion. The
litter is especially important in wood burning because of its high volatile
matter content, typically dU percent on a dry weight basis. In additon to
unburnt combustibles, lesser -unouits of nitrogen oxides and sulfur oxides
are emitted.
r'o'. ycycltc organic nuteiial (POM), a ninor but potentially important
component uf wood snnkr;, is d group of organic compounds which include;.
potential carcinogens such as benzy (a)pyrenu (BaP). POM results from the
combination of free rad Lc il species formed in tlie flame zone, primarily as a
cunsuquun :e of i-icomp le te combustion. Under reducing conditions, radical
chain prop'igatioi is enhanced, allowing the buildup of complex organic
material such as POM. HUM is generally found in or on smoke particles,
although soi.ie sublimation into the vapor phJse is probable.
Another itnpoitanl Constituent of wood smoke is creosote. 'Ihis tar-like
subjtrtnco will burn _f !. .ie t'ira is .sufficitMi tly hot, but at lower ttnpiira-
tures, it. may deposit on cool surfaces in the nxhaust system. Creosute
deposits are H fire ha/.ard in the f^e, but they can tn reduced if the
exh-tnst ductwork is insulated to prudent creo.sote condt.'ns.ition or tho exhaust
syste;u is cleaned regularly to remove any buildup.
Fireplace omissions art; highlv variable ind are a function of rsany wood
cli.iracter is tics and operating practices. In general, cundlLi-ms which
prniaoti:! i fast burn rate and a higher flant? intensity will enhance secondary
combustion and thereby lower i.-irissions. Conversely, higher emissions will
result from a slow hum rate md a lower flaiio intensity. Such generali-
zations apply particularly :o :ht_« -j^r'i.-.er st.igus of the burning cycle, when
sijjnifir.^nt quantities of ccn-.b'.ss t isle vol.itile matter are bein£ driven out
of the wood. Later in the burning cycle, wnen ail of the volatile nutter
has bt-c-n driven out of the wood, the charcoal t-iat rern^i ins burns with
rolarivelv few eiri-,sions.
1.9-2 EMISSION FACTORS
-------
Emission factors and corresponding factor ratings for wood combustion
in residential fireplaces are given in Table 1.9-1.
TABLE 1.9-3, EMISSION FACTORS FOR RESIDENTIAL FIREPLACES
Polllltsi'.C
Par ticulate
c
Sulfur oxides
Nitrogen oxides
&
Carbon monoxide
vocf
Methane
Nonme thane
Wood
g/kg
14
0.2
1.7
85
-
13
Ib/tun
28
0,4
3.4
170
-
26
Emission
Factor
Ratings
C
A
f;
C
D
Based on tests burning primarily oa<, fi; or pine, with moisture
.content ranging from 15 - 35%.
References 1, 3-4, 8-10. Includes condensible organics (back
half catch of EPA Method 5 or similar test method), which alone
accounts for 54 - 76% of the total mass collected by both the
front and back half catches (Reference 4). POM is carried by
suspended particulars matter and has been found to range from
0.017 - 0.044 g/kg (Referencps lv 4) which may Include BaP of up
to 1.7 mg/kg (Reference 1),
.References 2, 4.
Expressed as ^2* References 3-'i, S, JO.
^References i, 3-4, 6, 8-10,
References 1, 3-4, 6, 10- Dash - no data available.
References for Section 1.9
1. W. D. Snowden, et a 1_., Source Sampling of Residential Fireplaces
for Emission Factor Development, EPA-450/3-76-010, U. S. Environmental
Protection Agency, Research Triangle Park, NC, November 1975.
2. U. G. DeAngelis, et al., Source Asses_srr.eiitJ Residential Combustion
of Wood, EPA-600/2-80-042b, U. S. Environmental Protection Agency,
Washington, DC, March 1980.
3. P. Koeel, et al., "Emissions from Residential Fireplaces", CAR!* Report
C-tiO-027, California Air Resource:, Board, Sacramento, CA, April 1980.
3/83 External Combustion Sources 1,9-3
-------
4. D. G. DeAngelis, et al . , Preliminary Characterization of Emissions from
Wood Fired Residential Combustion Equipment, EPA-600/ 7-80-040, U. S.
Environmental Protection Agency, Washington, DC, March 1980.
5. H. I. Lips and K. J, Lim, Assessment of Emissions from Residential ar^i
Industrial Wood Combustion, EPA Contract No. 68-02-3188, Acurex
Corporation, Mountain View, CA, April 1981.
6. A. C. S. Hayden and R. W. ?Jri?aten, "Performance of Domestic Wood Fired
Appliances", Presented at the 73rd Annual Meeting of Che Air Pollution
Control Association, Montreal, Canada, June 1980.
7. J. A. Peters, PUM Emissions from Residential Wpodburnin^; An Environmental
Assessment, Monsanto Research Corporation, Dayton, OH, May 1981.
8. L. Clayton, e t a I . , "Emissions from Residential Type Fireplaces", Source
Tests 24C67, 26C, 29C6/, 40067, 41C67, 65C67 and 66C67, Bay Area Air
t'cUutinn Control District, San Francisco, CA, January 31, 1968.
9 . Source Testing for Fireplaces. Stoves, and Restaurant Grills in Vail,
Colorado (Drnf t) , EPA Contract No. 68-01-1999, Pedco Environmental, Inc.,
December 1977.
10. J. L. MutilbdLer, "Gaseous and Particular Emissions fron Residential
Fireplaces," Publication GMR-3588, General Motors Research Laboratories,
, MI. March 1931.
1.9-4 K.MTSSION FACTORS 5/83
-------
1.10 RESIDENTIAL WOOD STOVES
l.LO.l General1'2
Wood stoves are used primarily as domestic space heaters to supplement
conventional heating systems. The tw^ basic designs for wood stoves are
radiating and circulating. Common construction materials include cast
iron, heavy gauge sheet metal and stainless steel. Radiating type stoves
transfer heat tu the room by radiation from Che hot stuve walls. Circulating
type stoves have double wall construction with leavers on tht exterior wall
to permit the conversion of radiant energy to warm convection air. Properly
designed, these stoves range in heating efficiency from 50 to 70 percent.
Radiant stoves have proven to be somewhat more efficient than the circulating
type.
The thoroughness of combustion and the amount of heat transferred from a
dtove, regardless of whether it is a radiating or circulatory model, depend
heavily on firebox temperature, residence time and turbulence (mixing). The
"three Is" (temperature, time and turbulence) are affected by air flow
patterns through the stove and by the mode of stove operation. Many stove
designs have internal baffles that increase the residence tine of flue
gases, thus promoting heat transfer. The use of baffles and secondary
combustion air may also help to reduce emissions by promoting mixing and
more thorough combustion. Unless the secondary air is adequately preheated,
it may serve to quench the flue gas, thus retarding, rather than enhancing,
secondary combustion. Secondary combustion air systems should be designed
to deliver the proper amount of secondary air at the right location with
adequate turbulence and s>:friclent temperature to promote true secondary
combustion.
Stoves are further categorized by the air flow pattern through the
burning wood within the stoves. Example generic designs - updraft, downdraft,
crossdrafi and "S-£Low" - are shown schematically in Figure 1.10-1.
In the updraft air flow type ot stove, air enters at the base of the
Steve and passes through the wood to the stovepipe at the top. Secondary
air enters above the wood to assist in Igniting unburned volatiles in the
combustion gases. Updraft aLOVCS provide very little gas phase residence
time, which is needed for efficient transfer of heat from the gases to the
walls of the stove and/or stovepipe.
The downdraft air flow type of etove initially behaves like an upHraTt.
A vertical damper is opened at the top rear to promote rapid combustion.
When a hot bed of coals is developed, the damper IF closed, and the flue
gases are chen forced back down through the bed of coals before going out
the flue exit.
Ehe side or cruss draft is equipped witli a vertical baffle (open at the
bottom) and an adjustable! damper at the top, similar tu the downdraft. The
danger is open when combustion is initiated, to generate hot coals ;ind
adequate drart. The damper is then closed. The gases must then move down
5/33
External Combustion Sources 1.10-1
-------
under the vertical baffle, the flame is developed horizontally to the fuel
bed, and ideally the gases and flame come in contact at the baffle point
before passing out the flue exit.
i
f7$ -J
^ "77
•7^ -j
v • ^ — 1
\
1C
J
f -
I - C
K
lMI 1C fc^
<:
A
vT ^>
i f
_j
I
K
-/ ,c ^1^,
ld» or Crost Drllt
Figure 1.10-1. Generic designs of wood stoves based on flow paths
The S-flow, or horizontal baffle, stove is equipped with both a primary
and a secondary air iileL, like the updraft stove. Retention time within
the stove is a function of both the rate of burn and the length of the smoke
path. To lengchen the retention time, gases are kept from exiting directly
up the flue by a metal baffle plate located several inches above the burning
wood. The baffle plate absorbs a considerable amount of heat and reflects
and radiates much of it back to the firebox. Thp longer gas phase residence
time results in improved combustion when the: proper amounts jf air are
provided, and it enhances heat transfer from the gas phase,
Softwoods and hardwoods are the most common fuels for residential
stoves. Coal aud waste fuels, which burn at significantly higher temperature
than cordwood, are not included in computing emission factors because of the
relative scarcity cf test data available. The performance of various heaters
within a given type will vary- depending on how a particular design uses its
potential performance advantages. Much of the available emissions data came
frorri studies conducted on stoves designed for woodburning.
1, \.(j 2 Emissions and Controls
3-25
Residential combustion of wood produces atmospheric emissions of
particulars, sulfur oxides, nitrogen oxides, carbon monoxide, o^anic
materials including polycyclic organic matler (POM), and mineral constituents.
Organic species, carbon monoxide and, to a large extent, the participate
1.10-2
EMISSION FACVORS
5/83
-------
matter emissions result from incomplete comnnstton of the fuel. Efficient
combustion tends to lictit emissions of carbon nunuxide and volatile organic
compounds by oxidizing these comp-.iur.ds to carbon dioxide and water. Sulfur
oxides arise fron oxidation of fuel sulfur, while .litrogen oxides are formed
both from fuel nitrogen and by the combination of atmospheric nitrogen with
oxygen in tha combustion zone. Mineral constituents in the particular
emissions .esult from minerals released from the -jood matrix during combustion
am1 emriined in the combustion gaset-.
Wood smoke is composed of unbur.ied fuel - combustible gases, droplets
and solid particulates. Part of the organic compounds in smoke often condenses
in the chimney or flue pipe. This tar-liki> substance is called creosote.
If the combustion zone temperature is sufficiently high, creosote burns with
the other organic compounds in the wood. However, crmsote hur.is at a
higher temperature than other chemicals in the wood, so there .ire times when
it is not burned with the othf.r products. Creosote deposits are a fire
hazard, but they can be reduced if the. exhaust ductwork is Insulated to
prevent creosote condensation, or the exhaust system is cleaned rugularly to
remove any buildup.
Polycyclic organic material (POM), a minor but potentially important
component of wooH smoK.e, is a group of organic compounds which includes
potential carcinogens such as benzo(a)pyrene (BaP). POM results from the
combination of free radical species formed in the flame zone, primarily as a
consequence of incomplete combustion. Under reducing conditions, radical
chain propagation is enhanced, allowing the buildup of complex organic
material *uch as POM, POM is generally found in or on smoke particles,
although some sublimation into the vapo1" phase is probable.
Emissions from any one stove are highly variable, and they correspond
directly to different stages in the burning cycle. A new charge of wood
produces a quick drop in firebox temperature and a dramatic increase in
emissions, primarily organic matter. When all of the volatiles Vuive been
driven off, the charcoal stage of tht burn is characterized by relatively
clean emissions.
Emissions of particulaIf, carbon monoxide and volatile organic compounds
were found to depend on burn rate. Emissions increase as burn rates decrease,
for the xreat majority of the closed corabustLon devices currently on the
market. A burn rate of approximately three kilograms per hour ha.s been
determined representative of actual woodstove operation.
Wood xs a complex fuel, and the combined processes of conbustion and
pyrolysis which occur In a wood heater arc affected by changes in the
romposit-on of the fuel, moisture content and th-: effective burning surface
area. The moisture content of wood cep<:uut- OP. the type of wood and th<-'
amount uf time it has been dried (seasoned). The water in th»2 wood increases
the atncjunr of heat required to raise, the woo1', to its combustion point, thus
reducing the rate of pyrolys'.s until moisture is released. Wood moisture
hii, been found to have little affect on emissions. Dry wood (less than
15 percent moisture content) may produce slightly higher emissicus than the
commonly occurring 30 to 40 percent moisture wuot!. However, firing very wet
wood may produce higher emissions duo to smoldering and redi-ced burn rate.
The size of the wood also has a large effect on the rate of pyrolysis. For
5/83
External Conbustion Sources 1.10-3
-------
smaller pieces of wood, there Is a shorter distance for the pyrolysis products
to diffuse, a larger surface nrc>a-to-saass ratio, and ••» redaction in tlie time
required to heat tue entire piece of wood. One effect of log size is to
change the distribution of organic*? among the different effluents (creosote,
participate -natttr and condensible organlcs) for a given burn rate. Those
results also indicate that the distribution of the total organic effluent
among creosote, participate matter and condensibles is a function of fire-box
and sample probe tempera
Results of ultimate analysis (for carbon, hydroge-i ;md oxygen) o.f dry
wooc types am within one to two percent for the majority of all spec:es.
The inherent difference b'.tw«.en softwcod and hardwood is the greater amount
of resins in softwoods, which increases their he.iri;.g value by wefrh'..
Several combustion modif \ cat ion techniques are available tu reduce
emissions from wood stoves, with varying degrees of effectiveness. Some
techniques relate to modified stove design anj others r.o operator practices.
Propor nod ificat ions of stove design (1) wilY reduce pollutant formation in
the f:uel magazine or in the primary combustion zone ov (2) will cause
previously formed emissions to be destroyed in the primary or secondary
conbustion zones.
A recent wood stove emission control development is the catalytic
converter, <» transfer technology from the autornohile. The. c.itnlytic converter
is a noble metal i-uaiyst, such as palladium, cjattd en cerar.ic honeycomb
substrates and placed directly in the oxhaust gas J:low, where it reduces the
ignition tfnperature (flash point) of the ur.ournt hydrocarbons
-------
Emitaion factors and corresponding emission factor ratings for wood
combustion in residential wood stoves are presented in Table 1.10-1.
TAB^E 1.10-1. EMISSION FACTORS FOR RESIDENTIAL WOOD STOVES
Pollutant
Participate'1'0
Sulfur oxides.1.
e
Nitrogen oxides
f c
Carbon raonoxite '
g/kg
2)
0.2
1.4
130
Wood3
1 b / ton
42
0.4
2.8
260
Emission
Factor
Ratings
C
A
C
C
VOC8'C
Methane
Nonmethane
0.5
51
1.0
1UO
D
D
Based on tests burning primarily oak, fir or pine, with moisture
content ranging from 15 - 35%.
References 3-6, 8-10, 13-14, 17, 22. 24-25. Includes condensible
organics (back half catch of fcPA Method 5 cr similar test
method), which alone account for 54 - 76% of the total mass
collected by both from and back half catches (Reference 4).
POM is carried by suspended participate matter and has boen
found to range from '.;.!) - 0.37 g/kg (References 4, 14-15,
22-23) which may inc'lude HaP of up t3 kg/hr, emissions may decrease by as much as 55 - 60% for
.participates and VOC, and 25? for carbon monoxide.
References 2, 4.
^Kxpressed as NO . References 3-4, 15, 17, 22-23.
References 3-4, 10-11, H, 15, 17, 22-2?.
^References 3-4, 11, 15, 17, ?2-23.
References for Section 1.10
1. H. I. Lips and K. J. Lim, Assessment of Emissions from Residential and
Industrial Wood Combust ijjn, EPA Contract No. 68-02-33 8fi, ^curex
2,
3.
Corporation, Mountain View, CA, April 1981,
D. G. DeAngelis, et al . , Source Assessment; Residential Combustion of
Wood. EPA-600/2-80-042b, U. S. Environmental Protection Agency,
Washington, DC, torch 1980.
J. A. Cooper, "Environmental Impact of Residential Wood Combustion
Emissions and Its Implications", Journal^ of^ tKe Air Pollution i_ Con_trql_
Association. 30_(>] ): 855-861 , August 1980.
5/83
External Combustion Sources
1.10-5
-------
4. D. (i. DeAngelis, et al^ , Preliminary Cnarac tP-riza t ion of Emissloncs from
Wood-fired Residential Combustion ^quipmtint. EPA-600/7-"80-040,' U. S~
Environmental Protection Agency, Washington, DC, March 1980.
5. S. S. Butcher and D. I. Buckley, "A Preliminary Study of Particulate
Emissions from Small Wood Stoves", Journal nf the Air Pollution Contr.^
Association, 2_7_(4) : 346-348, April 1977.""
6. S. S. Butcher and E. tt. Sorenson, "A Study of Wood Stove Particulate
Emissions", JcaTnal^ of the Air t'oll.qr.ion Control Association.
_24(9): 7^4-728, Ju~ly~l979.
7. J. W. Sl.elton, a t al . ., "Wood Stove Testing Met!.;>ds and Some Preliminary
Experimental Results™, Presented -it thp African Society of Hooting,
Refrigeration and Air Conditioning Engineers (ASHRAE) Symposium, Atlanta,
(JA, January ;y?8.
d. D. Rossman et a1 . , "Evaluation of Wood Stove Eraisuiona", Oregon
Department of F.nviVoniaei'.tal Quality, Portland, OR, December l°iiO.
°. P. Tiegs, et aK, "Emission Test Report on Four Selected Wood Burning
Hiirau Heating Devices", Oregon Department of Energy, Portland, OR,
January 1981.
10. J. A. Peters and n. G. DeAngelis, Higri Altitude Testing of Residential
Wuoii-n.red Combustion Equipment, i.?A-<300/2--'}i-lf7, U. S. Envlronmer.taf
Protection Agency, Washingtont DC, September 19S1 .
K. A. C. S. i^yaen and R. W. Braaren, "Performance of Dosrrt^cic Wood-fired
AppliancPi", Presented at 73rd Annual Meeting of the AJ.r Pollution
Control Association, Montreal, Cau.ida, Jun<> 1980.
1^, R. J. Brandon, "An Assessment of the Efficiency and Emissions of Ten
Wood-fired Furnace?", Presented at the Conforenca OP Wo (id Combustion
Environmental Assessment, New Orleans, LA. February 1981.
13. R. R. Huhhlr and .1. B. '.. darkness, "Results of Laboratory Tests on
Wood-stove Emissions and Ef f ic tenc.ttes", Presented at the Conference on
Wood Coi.ibust ion Knvirni--nent.il Assessment, New Orleans, LA, February
1. R. iluhble, e t al , "Hxper Imenr.-il Measu r^mcn ts of Emissions fi'
ResidyntL.il Wood-burning Stoves", Presented at the International
on Residential Solid Fuels, Portland, OR, June 1981,
D. ]. M. Allen and W. M. Cooke, "Control of Emissions fro:n Residential
Wood Hurning by Combustion Modification", EPA Contract No. 68-02-2686,
Battelle Labor.i tor ios ., Ct.i.'.umbua, Oh, November 198U.
n. .1. R. Duncan, et_al^, "Air '^i/ility Impact Potential from Reslder; c ial
Wood-burning Stoves", 1VA Report 8U-7.2, Tennessee Valley Authority,
Muscle ShoalH, AL, March 1980,
1.10-6 EMISSION FACTORS
-------
17. P. Kosel, et al . , "Emissions from Residential Fireplaces", CARS Reporc
C-80-027, California Air Resources Board, Sacramento, CA, April 1980.
18. R. G. BarnetC and 1). Shea, 'Effects of Wood Burning Stove Design on
Paniculate Pollution", Ors,;on Department of Environmental Quality,
Portland, OR, July
19. J. A. Peters, POM Emissions from Residential Wood-burn i.ng; An Environ-
ment a 1 Asses t.mcn t , Monsanto Keseavch Corporation, Dayton, OH, May 1981.
'i 0 . Sour c e Testing for firep 1 ages, .Stoves, and Restaurant Grills in Vail,
Colorado (Draft), K^A Contract No. 66-01-1999, Pedco L.-ivirnnmental ,
Inc., December 1977
21. A. C. S. H.iyrlen and R. W. Braatan, "Effects of Firing tote and Design
on Domestic Wood Stcva Performance", Presented at the Residential Wood
and Coal Combustion Specialty Conference, Louisville, KY, March 1982.
22. C. V. Knight and M. S. Urahair. , "Emissions and Thermal Performance
Mapping for aa UnbaffU.a, Airtight. Moot Appliance and a Box Type Catalytic
Applicance", Proceedings of 1981 International Cppferenr.e on ReHidential
Solid Fuels, Oregon Graduate Center, Portland. OR, Jtn.e 1981.
23. C. V. Knight et al., "Tennessee Valley Authority Residential Wood
Heater Test Report: Phade I Testing", Tennessee Valley Authority,
Chattanooga, TN, November 1982.
2^. Richard L. Poirot ar.J Cedrlc R. Sanborn, "Improved Combust ic.
-------
1.11 WASTE OIL COMBl STIOM
1. 1 1. 1 Ccncrui
The largest count- of ttasie oil i> ii>cd *ulomol:.M cruak-
liile «'er\ice station*. of other automotive fluid- Other
*;!!irio» of wa.te oil unhide metal working lulirii ant>-. hea1 \ 'n droi jrlion fuel-. urn ma I anil tcyclalilc
uil> and fat^. and industrial uil
In 1975. 57 percent ol u a>tf rrunki ,i>e oil v*a> (Oii-.i/iiei) d> alUTiittlixf me I in ( omt'iitiondl boiler
e<|iiipmenl (Section 1.3). The rr-nainder »a> ri-fiiu-H (15 pern-fiO, hlfiidcil inUi n>a<< nil ur ai-|)hall
I 15 pcrrenl). <»r HM-d fur olh.-r n«>t)ftn'l ()nr|josf« (13 percent).1
I.I 1.2 EniiKfionc anil LonlruU
Lead craiwionn from burning waste 01! depend on the lead content of the oil «nJ on operating
condition*. Lead content mat \ar> fruni 000 to 1 1.200 ppm.J Aterupe romi-rUrali/m* have l>oi*n Mip-
fr»led a.f 6.000 ' and ur 10.000 ppm1. Purmp normal opvralio.,. about 50 percent of the lead 1» emitted
a- parlii'iilulc »illi Ilia* |tu».-V (Amiliiuiii'ii of fuel tuiilainii)^ III percent vaslc oil fiivi^ parliciilale
ranginji from 1 1 to IQ pr< cvnl lead. \>h con lent from ronil>ui>tion of fncUronluininp wj>tc oil is higher
than thai for dixlillali1 or roirinal l.'-'l oil. runginft from 0.03 lo .1.78 nci^lil percent, and load accounts
fur ulioiil 35 percent of the u-h produced in -urh cunilinslion.J
('iirn-nlK. controUurc not iiMiti'lv applied lo oil fin H combustion M>urff/-. \n exception is mil it >
lx>iler>. es|>c< iull\ in the niirlheH>lern I niled S|H|'.^. Prrt rent nie^l lit \uciiuni di>lillalion. -oKont
< \lrji (ion. -I'lllinj; .11 id or ivol i il iiuinj; iiiniiiii/' - 'ea of prnpcrh Oj'.orjted and fnainlainoci fabric
filler* '•* W piTii'nl effccliie for 0 i-i jm diaiiulrr Icdd and utlx-r -.ulinin ion »i/ed parlit ulule. but
• mil d di'^iree ul utiiliiil i.> intifi^iienlh n>i--l.-'
Tablt 1.11-1. WASTE OIL COMBUSTION EMISSION FACTORS
EMISSION FACTOR RATING: B
Pollutant
Paniculate*
Lead6
Em it lion factor
(ka/m3)
9.0 (A)
9.0 (P)
(Ib/loJgal)
75 (A)
75 (P)
References
5
1.2,3
*Th« letter A is for weight % of ash in the waste oil. To calculate the
paniculate emission fi.ctor, multiply t*>a ,t»b in the oil by 9.0 to 0*1
kilograms of paniculate «mitted per r\3 w jite oil burnrd. Example:
wh of waste oil is 0.5% th« emission factor is 0.5 x 9.0 = 4.5 kg
pirticulatc per m^ waste oil burned.
°Tht ie;:«ii P indicates that tht percen- lead .n the waste oil being pro-
cessed should be multiplied by the vetui giv
-------
K«'fer«-nr«-f for Siflion 1.1 I
1 . S. Wy all, el o/., preferred Standard) Palh A lo/vii* on I. fad Emission* from Statinnr.r\ So
< M'fiir of .Air Qiiulilt Planning and Si aiufaril-. I .S. Kn\ iron mould I I'l ulri I um \JJI-IK-I. Hr-i jr< h
Triangle Park, NC Seplembcr 1974.
.', S. Chansky, et of., '7'c.itf Automatic Lubricating Oil Reuse at a Fuel. EPA-600'5-" 1-032. IS
lal I'rtiU'i ' ion A|ii'i<>>. ^ J>liin^d>ii. I)'.. Si/plfmln'i 1'Kt
.>. Final Report oj the API Tatk Force nn OH Di.\ptisnl, American Petroleum Institute. New York ,
M. \la> IV70.
I. Background Information in Support oj the Drit-lopmtnt of Performance Standards fur the
Lead Additive Industry, EP\ Contract No. 6fl-0--2085. PEDCo-Enx ironmmtal Specialists. Inc..
Cncinnali. OH, January 1976
*>. Control Technique* for Lead Air £miiiio/u. EPA-450/2-77-012, U.S. Environmental Protection
Agency, Research Triangle P«rk, NC, December 1977.
1.11-2 EMISSION FACTORS 7/79
-------
2. SOLID WASTE DISPOSAL
As defined in the Solid Waste Disposal Act of 196S, ihr term "solid waste" means garbage, refuse, and other
discarded solid materials, including solid-waste materials resulting I rum industrial, commercial, and agricultural
operations, and from community activities It includes both combustibles and noncombustibles.
Solid wastes may be classified into four general categories: urban, industrial, mineral, and agricultural
Although urban wastes represent only a relatively small part of the total solid wastes produced, this category has
a large potential for air pollution since in heavily populated areas solid wante is often burned to reduce the bulk
of maleiill requiring Anal disposal ' The following discussion will be limited to the urban and industrial waste
categories
An average of 5.S pounds (2.5 kilograms) of urban refuse and garbage i>; collected per capita per day in the
United Slates.2 This figure does not include uncoUected urban and industrial wastes that are disposed of by other
means. Together, uncollccted urban and industrial wastes contribute ai least 4.5 pounds (2.0 kilograms) per
capita per day. The total gives a conservative per capita generation rate of 10 pounds (4 5 kilograms) per day of
urban'and industrial wastes Approximately SO percent of all the urban and industrial waste generated in the
United i^'ates is burned, using a wide variety of combustion methods with both enclosed and open
burningV Atmospheric rmissions. both gaseous and paniculate, result from refuse disposal o^.ei.ilions that use
combustion to reduce the quantity of refuse. Emissions from these combustion processes cover a wide range
because of their dependence upon the refuse burned, the method of combustion or incineration, and other
factors. Because of the large .lumber of variables involved, it is not possible, in general, to delineate when 3 higher
or lower emission factor, or an intermediate value should be used For this reason, an average emission facior has
been presented.
References
I. Solid Waste • It Will Not Go Away. League of Women Voters of the United States Publication Number 675.
April 1971.
2. Black, R.J., H,L. Hickman, Jr , A.I. Klee, A.J Muchick, and R.D. Vaughan. The National Solid Waste
Survey: An Interim Report. Public Health Service, Environmental Control Admimstiation Rockville, Md.
1968
3. Nationwide Inventory of Air Pollutant Emissions, 1968 US. DHEW, PHS, BUS, National Air Pollu'.icn
Control Administration. Raleigh, N.C. Publication Numbei AP 73 August 1970.
12/77 Solid Waste Disposal 2.0-1
-------
2.1 REFUSE INCINERATION
2.1.1 ProceM Description1-*
The most common types of incinerator* consul of a ref net or y- lined chamber with a grate upon which refuse
it burned. In some newer incinerators v/ater walled furnaces are used. Combustion products are formed by
heal ing and burning of refuse on the grate. In most cases .since insufficient underfire (undergrate) air is provided
to enable complete cu.Tibustion. additional over-fire air is admitted above the burning waste to promote complete
gas-phase combustion. In multiple-chamber incinerators, gases from the primary chamber flow to a small
secondary mixing chamber where more air is admitted, and more complete oxidation occurs. As truth as 300
percent excess air may be supplied in order to promote oxidation of combustibles Auxilmr\ burners arr
tometimea mitalled in the mixing chamber lo increase the combustion temperature. Many small-size incinerators
•re single-chamber uniti in which gases are vented from the primary combustion chamber directly into the
exKauit itaclt. Single-chamber incinerators of this type do not meet modern air pollution codes
2.1.2 Definition! of Incinerator Categories'-
No exact definitions of incinerator size categories exist, but for this report the following general categories
and description!) have been selected:
1. Municipal incinerators — Multiple chamber units often have capacities greater than 50 tons (45.3MT) per
day and are usually equipped with automatic charging mechanisms, temperature controls, and movable
grate systems. Municipal incinerators are also usually equipped with some type ol particular control
device, such aa a spray chamber or electrostatic precipita!or.
2, I ndutirial/commercial ineineratori — The capacities of thest jniti cover a wide range, generally between
SO and 4,000 pounds (22 7 and 1.800 kilogram*) per hour. Of either single- or multiple-chamber design,
these units are often manually charged and intermittently operated. Some industrial incinerators are
similar to municipal incinerators in size and design. Better designed emission control sytterns include gas •
fired afterburners or scrubbing, or both.
3 Trench incinerator)— A trench incinerate L is designed for the combustion of wastes having relatively high
heat content and low ash content. 'fi;e design of the unit is simple: a U-shaped combustion chamber is
formed by the tides and bottom of the pit and air is supplied from nozzles along the top of the pit. The
nozilea are directed at an angle below thehonzontf to provide a curtain of air across the lop of the pit and
to provide air for combust ion in thepil Thetrenchi.icm;rator is not as efficient for burning wastes as the
municipal multiple-chamber unit, except where cartful precautions are taken to use it for disposal of low-
ash, high-heat-content refuse, and where special attention is paid to proper operation Low construction
and operating costs have resulted in the use of this incinerator to dispose of mateiiab other than I hose for
which it was originally designed. Emission factors for trench incinerators used to bum rlu°e such
materikls' are. included in Table 2.1-1
4. Domestic inctnera:ors — This category includes Tidnrr !ors marketed for residential use fairly Dimple in
design. ?hey may have single or multiple cnambers anc' usually are equipped with an auxiliary burner to
aid combustion,
5. flue-fed incinerators — Thest units, commonlv found in .arge apartment houses, are characterized by the
charging method of dropping rifuse down !he incinerator flue and into the combustion chamber. Modified
flue-fed incinerators utilize afterburner* and draft controls lo improve combustion efficiency and reduce
emissions
12/77 Solid Wa.,le DUpoMl 2.1-1
-------
I
ro
TABLE 2.1-1. EMISSION FACTORS FOR REFUSE INCINERATORS WITHOUT CONTROLS3
EMISSION FACTOR RATING: A
t*rt ic.ulales
Ib/ton
Sulfur Oit(d««c
Ib/ton k*/N«
Carbon •oaoilJ*
IS/ton
Organic a*
kg/Ng HJ/-.DII
Mltrgg*n oxides*
V-B/Hg Ib/ton
Lead
kg/I* "IS/ton
V.
O
2!
H
O
cn
Multiple ctuaber, uncuntlolled 15 30
With serrlfap rhaaber ttnA
watet spray systenh ' 14
i ndus t r '. fll / cornm-1 c 1 d 1
Hulrl^'e chanl-er1 1-5 7
Slngli chamber11 7.5 IS
Tr-nrh1
J0,,d 6.^ 11
Rubbar tlrei 69 I IS
Nu.lclpal refuse 1A.5 37
C=.n.r<>l i-d »lrn 0-7 1.4
Pluc-Ud slaglo ctiaatxr0 IS V)
3 6
I.JiJ
1.25.1
0.0'i
2.5
2.5
'.5
0.4
n.s
17.5
17.S
5
10
35
35
10
20
20
10
0.75
0.75
1.5
!«««
7.5
1.%
1.5
1.5
1
11
"«R
15
1
1.1
1.5
'.5
10
3
10
0.2
Dotr-6tlc single chaHber
Ulchoac primary hurner1"
With ?r'.*irf a .rner9
17.i
1.S
35
7
0.5
0.5
tno
50
1
inn
2
Nei.
0.5
1
a£alsslon Eaetnrti are based on weight per unit velgh; of refa^e
rhnrgrr1.. Danh indlratrn no ^vallAhlr dar*.
""Auernge f^cfora j^lven ba&ed nn TPA pri)redur.?B for ;ocvner»for
stack testing.
cRxpresv:ed as sulfur dioxide-.
^Expressed m» afthane.
^Exprttflfi*d BB nltrngcn dioxide.
fR*fer«nce£ 5. 8-11. 2'—:8.
XRefercnrpr, S, A-14.
''Hoac Bunlclpal incinerators are equipped with at least this ouch
control; «ec Table 2-t~2 for appropriate el f lei end eu for utlter
contra IB.
cee 1, 5. 10, ! 1, H.
n •untclpal incinerator data.
'Referencea 3, S. 10. 15.
^Reference 7.
ed on dala For uom* r^nbustlan In ctnleal b«irnerc.
#r«ncfl> 9.
•r.nc.t 1, |t), ||, !}, |), it.
er-ncea T, II, 15.
erencea S, 10.
erenc« 5.
crencc J, 9.
1R
rRe
-------
6. Pathological incinerators — These are incinerators used to dispose of animal remains and other organic
material of high moisture content. Generally, these unit:' are in a size range ol 50 to 100 pounds (22.7 to
45.4 kilograms) per hour. Wastes are burned on the hearth in the combustion clumber. The units are
equipped with combustion controls and afterburners to ensure good combustion in j minimal emissions.
7. Controlled u\r ineineraion — These units operate on a ronti oiled combustion principle in which the waste
is burned in the absence of sufficient oxygen foi compUtt combustion in the mam chamber. This process
generates a highly combustible gas mixture (hut is then nurned with excess air in i secondary chamber.
resulting in efficient combustion. These units arc usually equipped with automa'ic charging mechanisms
and are characterized ry the high effluent temperatures reached at the en it of the incinerators
2.13 EmiaiionB and Controls'
Operating conditions, refuse composition, and basic incinerator design have a pionounced effect on
emissions. The manner in which air is supplied to the combustion chamber or chamber, has, among all the
parameter*, the great eat effect on the quantity of paniculate emissions. Air may be introdu :ed from beneath the
chamber, from the side, or from the lop of the combustion area. As underfire air is increased, and increase in fly-
ash emiwiona occurs. Erratic refuse charging causes a disruption of the combustion bed and a subsequent release
of large quantities of paniculate*. Large quantities of uncombusted paniculate matter and carbon monoxide are
alao emitted for an extended period after charging of batch-fed iinila because of interruptions in the combustion
proceaa. In continuously fed units, furnace paniculate emissions are strongly dependent upon grate type. The use
of rotary kiln and reciprocating grates resulia in higher paniculate emissions than the useof rocking or traveling
gratet.'* Emitaions of oxides of <-ijlfur are dependent on the sulfur content of the refuse. Carbon monoxide and
unburned hydrocarbon emission* may be significant and are caused by poor combustion resulting from improper
incinerator design or operating conditions. Nitrogen oxide emissions increase wit h an increase in the temperature
of the combustion zone, an increase in the residence time in the combustion zone before quenching, and an
increase in the excess a.r rates to the point where dilution cooling overcomes the effect of increased oxygen
concentration.'*
Hydrochloric acid emissions were found to approximate 1.0 Ib/ton offend in early >crk14 and 1.8 Ib/'ton in
more recent work." The level can be sharply increased in areas where large quantities of plastics are consumed.
Methane levels found in recent work" range from 0.04 to 0.4 Ib/ton of feed.
Table 2,1-2 lists the relative collection efficiencies of parlicuiste control equipment used for municipal
incinerators. This control equipment has little effect on gasecv'i emissions Table 2.1-1 summarizes the
uncontrolled emission factors for the various types of incinerators previously diseased.
Table 2.1 2. COLLECTION EFFICIENCIES FOR VARIOUS TYPES OF
MUNICIPAL INCINERATION PARTICULAR CONTROL SYSTEMS*
Type of system
Settling chember
Settling chamber and water spray
Wetted biMles
Mechanical collector
Scrubber
Electrostatic precipilalor
Fabric filter
Efficiency. %
0 to 30
30 to 6C
60
30 to 80
80 tc £5
90 to 96
97 to 99
aHetfreice< 3. 5, 6. and 1 / ihrojgn 21
12/77 Solid Waste Disposal 2.1-3
-------
References for Section 2.1
1. Air Pollutant Emission Factors, Final Report, Resources Research, In-
corporated, Re.Jton, VA, prepared for National Air Pollution Control Ad-
ministration, Lurham, KG, under Conl:ract Number ^PA-2i!6:»-l 19, April
19 TS.
2. Control Tcchnlqufc 3 for Car SonMono xide Emissions from Stationary Sources,
LI.S. ~DHEW, PHS, ~EHS7 National ATr Pollution Control A'dmfnistration,
Washington, DC, Publication Number AP-65, March 1970.
•*• \*_r Pollution EngjLjit^erjng Manual, U.S. DHEW, PHS, National Center for
Air" Pollution Control, Cincinnati, OH, Publication Number 999--AP-40,
1967, p. -413-503.
4. J. UeMarco. et al. , Incinerator Guidelines 1969, U.S. DHL'W, Public
Health Service," "Cincinnati.. OH, SW. 13TS, I960," p. 176.
5. C. V. banter, R. G. Lunche, and A. P. Fururich, Techniques for Testing
Air Co.itaralnants from Combustion Sources, J. Air Pol. Control Assoc.,
£(4): 191-199, February 1957.
6. W. Jens, and F. R. Rehm, Municipal Incineration and Air PollutionCon-
trol , 1966 National Incinerator Conference, American Society of Mech-
anical Engineers, New York, NY, May 1966.
7. J. 0. Burkle, J. A. Dorsey, and «. T. Riley, The Effects of Operating
Variables and Refuse Types on Emissions from a Pilot-tlcale Trench In-
cinerator, Proceed"'PRB of the 1968 Incinerator Conference, American
Society of "Mechanical Engineers^ ~New Y~orkT, ~NY, May 1968, p. 34-Al.
8. J. H. Fornandes, Incinerator Air Pollution Control, Proceedings of
1968 National Incinerator Conference, American Society nf Mechanical
Engineers, New York, NY, May"l968, p. 111.
9. Unpublished data on incinerator testing. U.S. DHEW, PHS, SHS. National
Air Foliation Control Administration, Durham, NC, 1970,
10. .1. L. Stear, Municipal Incineration: A Review of Literatjure, U.S.
Environmental Prot«crlon Agency, Office of Air Programs, Research
Triangle Park, NC, CAP Publication Number AP--79, June 1971.
11. E. R. Kaiser, et al. , Mo d i f i c a t i o n s to Re d i- re Em i s s i o n a from a Fi.-ie-
Jed Incineraror, New York University, College of Engineering, Report
Number 552.2, "June IVW, p. 40 and 49.
12. Unpublished data on incinerator emissions. U.S. DHEW, PHS, Bureau of
Solid Waste Management, Cincinnati, OH, 1969.
2.1-4 EMISSION FACTORS 12/77
-------
13, E. R. Kaiser, Refuse Reduction Processes in Proceedings of Surgeon
General's Conference on Solid Wast ^Management, Public Health Service,
Washington. DC, PHS Report Number 1729, July 10-20, 1967.
14. Walter R. Nlssen, Systems^ _Study_ of Air Pollution from Municipal Incin-
eration, Arthur D. Little, Inc. Cambridge, MA, prepared for National
Air "Dilution Control Administration, Durham, NC, ur.der Contract Number
CPA-22-69-23, March 1970.
15. Unpublished source test data on incinerators, Resjurces Research, In-
corporated, Reston, VA, 1966-1969.
16,, Communication between Resources Research, Incorporated, Restnn, VA,
and Maryland State Department of Health, Division of Air Quality Con-
trol, Baltimore, MD, 1969.
17. F. R. Kenn.-, Incinerator Testing and Test Results, J. Air Pol. Control
Asrnc. £:199-206, February 1957.
18. R. L. Stenburg, et al., Field Evaluation of Combustion Air Effects on
Atmospheric Emissions from Municipal Incinerations, J. Air Pol. Control
Aasoc. lJ2:83-89, February 1962.
19. E, E. Sraauder, Problems of Municipal Incineration, Proceedings of Air
Pollution Control Association, West Coast Section, Los Angeles, CA,
March 1957.
20. R. W. Gerstle, Unpublished data: revision of emission factors based
on recent stack teats, U.S. DHEW, PHS, National Center for Air Pollu-
tion Control, Cincinnati, OH, 1967.
?.l. A Field Study of Performance of Three Municipal Incinerators, University
of California, Berkeley, Techn lc_al Bu 11 e t in .6:41, November 1957.
22. J, Driscol, et_al., Evaluation of Monitoring Methods and Instrumentation
to r Hydro car bons and Ca rbon Monoxicte iji Stationary Source Emissions,
IpiTbTicaTicm NoTTPA-R2~72-106T"Novomber 1977.
23. J. A. Jahnke, J. L, Chancy, R. Rollins, and C. R. Fortune, A Research
Study of Gaseous Emissions from a Municipal Incinerator, J. Af.r Pollut.
Control ASSOC. 27:7^7-753, August 1977.
2^« Cjmtrol Techniques for J^gad Air EroiEisionB , EPA-450/2-77-012, U.S. Envir-
onmental Protection Agency, Research Triangle Park, NC, Decc'raber 1977.
25. W. E. Davis, Emissions Study of Industrial Sou£ce of Lead Air Pollutantjs,
JJ70, EPA APTD-1543, wT F. Davis and Associates "Leavood, KS7 April
'973.
12/81 Solid Waste Disposal 2,1-5
-------
26. EnisRion Tests Nos. 71-CI-05 and 71-CI-ll, Office of Air Quality Planning
and Standards, U.S. Environmental Protection Agency, Research Triangle
Park, NC, September 1971.
27. K. J. Yoat, The Environmental Flow of Cadmium and Othar Trace Metals: Pro-
gress Report^ tor July 1, 1973__ toi June TO, 1974, Purdue University, West
Lafayette, IN.
28. F. I.. Clcss, et j 1., "Metal and P.irt icv.Iatn Emissions from Incinerators
burning Sewage Sludge", Proceedings of the 1970 National Incinerator Con-
ference of ASME, 1970.
2.1-6 MISSION FACTORS 12/Bl
-------
2.2 AUTOMOBILE BODY INCINERATION
2.2.1 Process Description
Auto incinerctors consist cf u single primary combustion clumber in which one or several partially snipped
cars are burned, (lircs are removed.) Approximately 30 to 40 inmuli'j is required to burn two bodies
simultaneously.- As r.'.any as 50 cars per day can he burned in (his balch-lypc operation, depending on the
capacity of the incinerator. Continuous operations in which cars are placed on a conveyor belt und passed
through a tunnel-type incinerator have capacities of more than 50 cars per 8-hour day.
2.2.2 Emissions and Controls1
Boih the degree of combustion as determined by the incinerator design and the amount of combustible
material left on the car greatly atTecl omissions. Temperatures on the order of I200°F (6SO°C) are reached during
auto body incineration.2 This relatively low combustion temperature is a result of the large incinerator volume
needed lo contain the bodies as compared wild the small quantity of combustible material. Tlie use o. overilre air
jel- in lite primary combustion chamber increjsrs combustion efficiency by providing air and increased
turbulcp-e.
It: an attempt to reduce the varkxib aii pollutants produced by this method ol burning, some auto incinerators
are equipped with emission control devices. Afterburners and low-'-oIlugc clcctrustatic precipitators have been
used lit reduce parliculate emissions; (lie fonncr also reduces some of the 1,'aseous i-missions.-5-* Wlien
afterburners are used lo control emissions, the temperature ii. the secondary conilntstiun chamber should be al
least 1500 F (HIS C). Lower temperatures result in higher emission. Emission factors fur auto body incinerators
arc prcsu'iled in Table 2.2-1.
Table 2.2-1. EMISSION FACTORS FOR AUTO BODY INCINERATION*
EMISSION FACTOR RATING: B
Pol.utants
Participates6
Carbon monoxidec
Hydrocarbons (CHJC
Nitrogen oxidpj (N02Sd
Aldehydes (HCOH)d
Organic acids (acetic) d
Uncontrolled
Ib/car
2
2.5
0.5
0.1
(J.2
0.21
kg/car
09
1.1
0.23
0.05
0.09
0.10
With afterburner
Ib/car 1 kg/car
1.5
Nei)
Neu
0.02
0.06
or?
068
Meg
Neg
0.01
0.03
003
aB»i«i en 250 Ib (113 kgl ot comb'jitible n.aienal 011 jtnpped car
°Rpftfenc« 2 and 4.
cBaied en dala for Open burning and References 2 and 5.
aRe(eience 3
4/73
Solid Waste Disposal
2.2-1
-------
References for Section 2.2
1. Air Pollutant Emission Factors. Final Report. Resouices Research Inc. Reston, Va. Prepared tor National Air
Pollution Control Administration, Durham, N.C., under Contract Number CPV22-69-11°. April 1970.
2. Kaiser, E.R. and J. Tolcias. Smokeless Burning of Automobile Bodies J Air Pol. Control Assoc ^2:64-73,
February 1962.
3. Alpiser, P.M. Air Pollution from Disposal of Junked Autos. Air Engineering. 10:18-22, November 1968
4 Pnvate communication with D.F. Walters, U.S. DHEW, PHS, Division of AK Pollution. Cinc.nnati. Ohio. July
19, 1%3.
5. Gentle, R.W. and D.A. Kemnitz. Atmospheric Emissions from Open Burning. J. Air Pol. Control Assoc.
/7:324-327. May 1967.
2.2-2 EMISSION FACTORS 4/73
-------
2.3 CONICAL BURNERS
2.3.1 Process Descrip tion'
Conical burners are generally a truncated metal cone with a screened top vent. The charge is placed on a
raised grate by either conveyor or bulldozer; however, the use of a conveyor results in more efficient burning. No
supplemental fuel is used, but combustion air is often supplemented by underfire air blown into the chambei
below the grate ?nd by overfire air introduced through peripheral openings in the shell.
2.3.2 Emissions and Controls
The quantities and types of pollutants released from conical L.'rren ire dependent on tiff composition and
moisture content of the charged material, control of combustion uir, tvp*. of charv ;»fl system used, and (he
condition in which the incinerator is maintained. The most critical ot inese (actors teems to be the level of
maintenance on the incinerators. It Is not uncommon for conical Lumen to hive missing doors and numerous
holes in the shell, resulting in excessive combustion air, low te nperatures, and, therefore, high emission rates of
combustible pollutants.2
Participate control systems have been adapted to tunica! burners with some success. These control systems
include water cur.'ains (wet caps) and water scrubbers. Emission factors for coni'.al burners are shown in Table
2.3-1.
4'73 Solid Waste Disposal 2.3-1
-------
Table 23-1. EMISSION FACTORS FOR WASTE INCINERATION IN CONICAL BURNER?
WITHOUT CONTROLS*
EMISSION FACTOR RATING. B
Type of
waste
Municipal
refusth
Wood refuse*
P.irtiLulaies
Ib/ton
20(101060)°°
1'
79
20rt
kg/MT
10
0.5
3.5
10
Sulfur oxKJCi
Ib/ton
2
01
kg/MT
1
0.05
Carbon monoxide
Ib/ton
60
130
kg/MT
30
65
Hydrocarbons
IbAon
20
11
kC/MT
'0
bb
Nitrogen oxides
Ib/ton
5
1
kg/MT
2.5
0.5
LT
C
^f
•n
>
O
rfMa»sti!(* content a^ fired is di^roKimdlely 50 ;.'.'Cent tor wood waste.
bE > ,-epi for ^articulates, factors are based on comparison with other waste dispatal uncitccs.
cUse h..«> ,«e of 'an^e 'or metmiueni oueraiions charged wuh a bulldozer
<*".-»•' He«e-cnce 3
"•'References 4 through 3
' Salisfaciorv operation or open y rrainiamed burner with adjustable underfire air lupolv and adiuftable, tangential owerfi,.- air .nleiv apprommateiv BOO rerc>n;
excess air and 10O°f (370°C) exit gas lenv^raturf
qUns,T 15* actor v operation procfly mjinramed burner wilh-jdial overrnc air supply near bOTtom of jhell. apvoairrwlely 1700 [jercent e cceis air end 400 F (704 Cl
rKti qu!, leniprrurure
hVery unutisfactory operation: Improper, maintained burner with radial overfire air supply near bottom of iheil and mai y gaping holes m shell, approximately 1500
iK-rctT.t BKcess air and 400TF li»°CI i. -it c
-------
References for Section 2.3
I. Aii Pollutant Emission Factors Final Report. Resources Research Inc. Reston, Va, Prepared Tor National Air
Pollution Control Administration, Durham, N.C., under Contract Number CPA-22-69-119. April 1970.
I Krcichelt. T.E. Air Pollution Aspects of Teepee Run fn. U.S. DHEW, PHS, Division of Air Pollution.
Cincinnati, Ohio. PHS Publication Number 999-AP-28. September 1966.
J. Magiil., P.L. and R.W. Benuliel. Air Pollution in Los Angeles County: Contribution of Industrial Products.
Ind. Kng.Chem. 44 1347-1352, June 1952.
4. Private communicaliun with Public Health Service, Bureau of Solid Waste Management, Cincinnati, Ohio.
October 31, 1969.
5. Anderson, D.M.,.'. Lie ben, and V.H. Sussman. Pure Air for Pennsylvania. Pennsylvania State Department of
Health, Harrisbu'g. November 1961. p.98.
6. Boubel, R.W. et al. Wood Waste Disposal and Utilization. Engineering Experiment Station, Oregon State
University, Corvallis. Bulletin Number 39. June 1958. p 57.
7. Netzley, A.B and J.E. Williamson. Multiple Chamber Incinerators for Burning Wood Waste. In: Air Pollution
Engineering Manual, Dank I son, Jj\. (ed.). U.S. DHEW, PHS, National Center for Air Pollution Control.
Cincinna'i, Ohio. PHS Publication Number 999-AP-40. 1967. p.436-445.
B. Droege. H. and G. Lee. The Use of Gas Sampling and Analysis for the Evaluation of Teepee Burners. Bureau
of Air Sanitation, California Department of Public Health. (Presented at the 7th Conference on Methods in
Air Pollution Studies, Los Angeles. January 1965.)
9. Boubel R.W. Paniculate Emissions from Sawmill Waste Burners. Engineering Experiment Station, Oregon
State University, Corvallii. Bulletin Number 42. August 1968. p.7,8.
4/73 Solid Waste Disposal 2.3-3
-------
2.4 OPEN Bl RMNG
2.4.1 General'
Open burning can b« done tn opeii drums or baskeU. in fa-Ids and yard?, and in larjcc open dumps or pits.
Materials commonlv disposed of in this manner arc municipal waste, auto body components, lard^ape refuse,
agricultural field refuse, wood refuse, bulky industrial rely*1, and leaves.
2.4.2 JunisHiona1-1*
Ground-level open burning is affected b\ many variable including »ind. ambient tempera I uie . c uinpu-iliun
and moisture content of the debris burned, and compactness of the pile. In general, the relatively Ion
temperatures associated with open burning increase the emission of particulales, ivrbon munoxide, add
hydrocarbons and suppress Ih* emission of nitrogen oxides. Sullur oxide emissions are a direct function of (he
sulfur content of ihe refuse. Emission factors are presented in Table 2.4-1 t'ur tin- open burning of muninpal
refuse and automobile components.
TaM« 2.4-1. EMISSION FACTORS FOR OPEN BURNING OF NONAGRICULTURAL MATERIAL
EMISSION FACTOR RATING: B
Source
Municipal refuse'*
kB/Mg
Ib/con
Automobile
coaponertsc
kg/Kg
Ib/ton
Partlculatp
A
16
100
Sulfur
oxides
0.^
1
Neg.
Neg.
Carbon
monoxide
«
85
62
125
voca
methane nonmc:han(
6.', 15
13 30
3 16
10 32
Nitrogen
oxides
3
6
2
aDacn Indicate that VOC emissions art; approximately 2SK njtltiunn, IX other sdtum tun ,
18Z oleMtn, i2I others (oxygenates, acetylene, nromattcs, tracn formaldehyde).
^References 2, 7.
cReferencea 2. Upholstery, belts, hoses and I Ires hurned Lo
Emissions l'-om agncultaral refijsc burning a -e dependent mainly on the moislun1 content ul the refuse and.
in the case of thr field <:rops, on whether the refu e is burned in a heudfireo-a backfire (Head(irr>are started at
the upHind Side jf a field and allowed to progress in ihi. direction oi the wind. v,hercasharkfire> arc Marled at the
downwind edge and (tirceJ to progress in a direct ion opposing the nind.) Other \ariable;- "urhas fuel loadinp (bnw
murh refuse material is burned per unit of land area) and how ihe refuse is arranged irhai i*. in pile*, rows, or
spread out) are also important in certain instances. Emission factors for open agrirullural burninnart- presented
in Table 2.4-2 as a function of refus*- lype and also, in certain instances, as » function of burning tcchniqiu's.
and/or moisture content when these variables are knnwn to significantly affei-l emissions. Talile 2, \ 1 also
presents typical fuel loading \ alues associated with each Ivpe of refuse The^e values ran \te used, alrmg with (he
corresponding emission Faclors. to estimate emissions from certain categories of ugrii'ijlliiral buriiinp when the
specific fuel loadings for a giien area are riot known.
Kmis-Mon* from leiif burning are dependent upon the moisture content.
-------
Isi
Table 2.4-2. EMISSION FACTORS AND FUEL LOADING FACTORS FOR OPEN BURNING
CF AGRICULTURAL MATERIALS'
EMISSION FACTOR RATING: B
X
3
1 '
| Carbon
| PanlcuU'r1' J Monoxide
Rcfi;.'f Call-gory j kg/Ng Ib/ton 1 kg/*» Ib/ion
1 1
Kind Hi ops'1 ' | '
Vrsj". I't.'H '11 21 ! M 117 ;
B.irilrt.q t.-.-Uiu-vi— ' -mi ' | J
A- ,..!• i,;.i-f ' 2't 40 ' 7S 1 ,0 '
».irl,-« | 11 .'» ' (8 1W
*. -r,, ' 7 r« ' 'i4 IOR |
;i.iss. . ' i 1>. ' V) lOi |
"•in.-.iji;.!.-* ' '. H i >b 112 i
S.iMtowtr 9 irt 72 144 J
.... ^ ^
.:..rt' .r- v.r ,, ,,:i
ti.,,11 fr.'i:' '22 4 ) <>1 Md '
•1 !«.- («i I.M li 12 70 |H ;
•i ,.. ' ?J 44 ' <>H 1 17
-•:..- 11 22 hi 12H
l.u >l i r.- hur ti i,'k ' ' '
\l • .!• t ' 1 . "> *•> • •"
H. , i 'r l>, ,. , ' t \' ...-- -,'i " ' H«
1 I. (ti hi) . .' - , ' 17 ' !•> 1 n)
•>.,!•. 11 .'1 ' <>H 1 Mi '
. •"•!- ft 11 | )4 10H
.' I.M' l'r-i|i-< 1 'I'M ')! '
: • -».• i i. I « 1 i 42 H ,
.,-.!!. I i^li. ; t""ihl'— .-.') 11 2? l',4 )'!<) •
r i:. ~ fait i .... j,) ) ; ' 17 14 '
vocr
Methane j Nonm
kg/Mg Ih/ton j kg/Mg
!
i
2.7 5.4 ' <)
2.2 4.S ' 7.i
2 4 ; «J
U.7 1.4 ' 2.1)
2.2 i.S = J.i
1 2 ! 1
1.2 7.4 ' 4
1 ft ' 10
1 2 1.5
I).i>-2 1.2-l.H 2-h
'}.', 11 ' in
4 '.H ' 11
it.-) •* ' n
J O I'l
' '. /
1.1 2.h ' .5
•j.H l.» i
I . •• ) -i . ',
U.2 'I.S i;.H
1.? h.S ' I'l
'Fu«-l 1. i.«llnK F,,r"ir
lb/ton [Mg/hectarc ton/acre
1H i.1! 2
»!<) ' 3 . '• 1 . '.
IS ' 1.H 1. 7
: 2 •* . 4 •. . ?
•> ) . 1 1 . '
S ' (1.7 J.ll
20 2.9 1.1
i-17 H-4^, t-17
JH 1 .H i|. M
1<> 'i.'l ? .">
I j ^ . ^ | , n
:v .- .>. J.S
1 1 :>.•> i.o
! . I.*! 1 .«!
•) 4.1 1,9
! 'l . <1 .' . ')
9 ;. j j.i
l.'l 'J.I ".1
00
be
-------
OB
s.i pin.. i
21
0
6
10
7
4
12
6
?
1
•>
17
*
IZ
2ft
23
21
J4
M
22
40
28
28
16
57
21
ZH
21
70
52
46
at
56
i?
33
114
42
57
"2
47
HO
90
195
1.2
1
0.4
1
T.It
I.?
1.)
0.4
1.2
0.5
2
U.6
L
Cl.i
2.8
0.6
1.7
2.5
2
1
2
>..5
3
1.7
1
4
I .3
2
o.;
2
5.7
1.2
1.3
4
3
I .5
J
12
5
3
4
1.5
7
J
3.5
1
3
1
1
5.5
14
4
7
2
6
19
4
r.
3.6
3.6
5.2
4
3.4
2.2
2.2
2.2
4.9
4.5
2.7
2.7
2.7
157
't«tii nt
^:i r t ini
i*>l lucant f«°4t t«4 /weight of refute alter* •>! burned.
t H *D^ f t «• r fr^HB itfist .if^rini rural rprufle burning hrt
found to bt In th<*
1.6
1.6
2.1
1.8
i.5
1.0
1.0
1.0
2.2
3.0
I.I
2.5
2.6
1.2
1.2
-; ions
f<-iu->
refuse
opresoni
will hr
I.- Wh
Iir^d •«
l 1 i Ih/l
r- fi»r Jr
.-.i-i? 10 ''
voc emi st ion- .-ivcrdge 222 morhane, 7.^2 ntiirr s^iurAtiig, 17^ olrflna. 15Z arerylcru', 1^.5r<
HonrfMed VOf< .ire t-icpecced In Include aldrhydrw , ki.'tunes, arcMKlClcs, eye Lopar^f f I is .
'" >"nlssljn iivtor,, Hefprence 14 tor fuel loading lactorn.
frlils, n» slgniflmnt difference exldts between «*l»lon> frou headftrlng ur tuc^f i r i ng .
«-*, i ss ions «inij.*r typlcil high nolsture condlti'ms. If FeiitS .ire dried Co <1 SZ aolaturt?, part U'ulate
r...!'ic..>1 hy 10Z, CO cvl.ssluns ill, VOC /4Z.
l jnrltrJppl* is ^llow*f-. |<« r t l.-nljte e« I. 11 1 one will lncr»aae La 11.5 kg/Hg (23 Ib/ton) and VOC will tncffiae to
nn).
U ST molslur*) rice stiiw. '. ' c icn tf»w Is bumed
nrc'i.i
fiTenr
* :''>. S.jc Si-rilon 8.12 for Jiscuaslon of ajgar cane burning. The following fuel loading factors are rii (»>
r'-n- .-nrr-'sponding sMi's: l.oiilslaru. d - 13.6 >1g/nectate (3-5 toi/»ere); Florida. II - 19 Hg/hec t.ire
.m/acri'); Hawaii, 10 - <*b Mg,'hectar« (11 - 17 con/jcre) . For other arr.is, valura generally increaae with le
ng season- L'so tht? liirgrr p. •* of thr iknlM.ilon lactur ran^e frr lover IndUlng fdctors-
for dL-flrlllon «il hf^ldf 1 r Ing .
lot ihrllnUi'in of !;va'i Is tni- purpose (if a burn, (16 Ke/hrolirj (30 ton/acre) nf mate ul 1 I ho produced .
. NO emissions i-srimatr.t .M 2 kg/Md (4 Ih/ton).
Ki
-------
hydro' arbon. and paniculate tmiRMons. Inci easing the di-nsily of the piles increases .heamuunt of hydrocarbon
and particulate emissions, but has a variable effect on carbon monoxide emission;. Arranging I lie leaves in
conical piles and igniting diuuuJ the periphery of the bottom proves to the leas) desirable method ol burning.
Igniting a single spot on the top of the pile decrease; the hydrocarbon and paniculate emissions IJrbon
monoxide emissions with top ignitiondcerrjM's if mniMtirr cont-nt is high but increases if moiMure content is
low. Parlicu'jle. hydrocarbon, and carbon monoxide emissions I mm windrow ignition (piling the leaves into a
long row anil igniting one end, allow rig it to burn toward the other end) ,»re intermediate between top and bottom
ignition Fnission factors for leaf burning are presented in Table 2.1-3.
For ni ire detailed information on lhi« -uhjei 1. ihc reader shoi'ld roiiMill ihe releri iuv- cited at the end of
I \\i-
Table 2.4 3. EMISSION FACTORS FOR LEAF BURNING18-19
EMISSION FACTOR RATING: B
Leaf Speclei
Black Afh
Hod-nto Ash
White Aih
Ca'.alpa
Horse Chestnut
Ci.t t ontfoo-4
American Elm
I ucalyptui
Svrct Can
Blirk Locate
Hagnal la
Silver rU pie
Aocrlcan Sycamore
Calitornia Sycamore
Klip
Red Oak
Partlculateb
kg/Mg Ib/ton
18
16
21 , 5
8.5
27
19
13
18
16.5
31
6.5
33
7.5
"i
If)
46
Sugar Maple 26.5
Unspecified 19
36
32
43
17
38
26
36
Carbon
kg/M
63.
ai.
57
44.
73.
45
59.
45
J3 I 70
JO 1 65
13 | 27.
66 il
15
57.
10 52
20 ; is.
92 ' US.
53 ! 54
18 : 56
5
5
5
5
5
5
5
5
•,
raonoxldt :
" '
Ib/ton
ItM
127 5
161
113
89
147
90
119
90
UO
130
i5
11)2
115
104
77
137
108
5
6
2
8
6
4
5
11
i
tu
2
1
3
14
3
112 f>
vocc
Methane ' Sonme thane
/Kg Ib/ton ! kg/Mg
"
.5 11 ! D.5
10 ! 12
.5 13 ' 16
.5 5 ; 6.5
17 1 20
12 ' It
3 ! 9.5
.5 11
10
22
4
2 LI
.5 5
13.5
12.5
26
5
24.')
5.5
.5 3 3.5
6
28
7.5
14
Hi 20
12 ' U
lb ton
27
24
32
13
40
28
19
27
2'j
52
10
49
11
7
15
69
40
28
'R»f*i cenccis 18-19. Factors 3r,; an arlchmeti' ^vur.tgu of results obcalnrd by burning hi-.
content conto-ll pll^s. Ignited cither at the top or around the periphery of the hoct >n.
ir ra ngernent w^a only Cvsled on Mudeslu Asvi, CnlaljM, AmvrU-'iii Klrn( Sweet (ruii, 'Hlv,'; ^l^p
result! «re Included In the av»r-igt>s for these apeelei.
^The majority ol part Uul;it^ 14 s thmi'.-ron tn slz°.
cT*scs :ndK»ce that VOC entss'.ons ,u«rj^i? 29S nethane, \\Z o:her s-uuni'.'^, 13'i oleftris
( ^ rofia 1 1 -• s , K-p'ylent1, nxy^endtpq).
,& low aola
*i- windrow
Hnd Tulip,
.ither
References for Section 2.1
1. Vir ['ollutant Kmisiion Factors. Final Report. Heiciurc«-< He.searrh. Inc., Reston, Va I'rt-pared lor \flliona!
Air Pollution (iontrol Administration. D'irharn. N.. April l^TO
2. Cr>r;lle. K. W . and D. A, Kemnil?. Atmosphere- KmiSMons from Open Burning. J. Air Hoi Control ASMM-.
^:324-:J27 Max lOtoT.
2.1-4
EMISSION FACTORS
5/83
-------
3. Rurkle, J. O.. j.A. Dorsey, and B. T. Riley The Effects of Operating Variable and Refuse Types on
Emissions from a Pilot-Scale Trench Incineriior. In: Proceedings of 1968 lucineralor Conference.
American Society of Mechanical Engineers New York. M-^y 196B. p. 34-41.
4. Weisburd, M. 1. and S. S. Griswold leds.). Air Pollution (Control Field Operation.-. Guide : A Guide fi-r
Inspection and Control. I .S. DHEW, P'lS, Division of Air Pollution, Washington, D.C..PHS Publication
No. 937. 1%2.
5. L npubli>hed daia on estimated major air contaminant emissions. Stale ol .New York Department of Health.
AILanv. April 1. 1968.
6. Darley, K. F. f • al. Contribution of Burning ol Auri^ullural Wastes to Phoruchemical Air Pollution J. Air
Pol. Control Assoc\ J6:685-690, December I9u6,
7. Feldstein, M. et al. The Contribution ol the Open Burning o I Lund Clearing Ut'bris lu Air Vollulion J. Air
Pol. Control Assoc. I3:* \2 .">l"., November 1963
8 Boubel, R. W., E. F. Darley, and E. A. Schuck Emissions from 8u rning Grass Si ubhle and Slra w, J. Air Pol.
Control Assoc. J9:4'J7-500, July 1969.
9. Waste Problems of Agriculture and Forestry. Environ. Sri. and Tech. T:498, July 1968.
10, Yamale. G. cl al. An Inventory of Emissions from Forest Wildfires, Forest Managed Burn*. and Agricultural
Burns and Development of Emission Factors for Estimating Atmospheric Enliven:, from Ko^esl Fires.
(Presented at 68lh Annual Meeting Air Pollution Control Association, liustun. Junt- 1975.)
I 1 . Darley , E. F. Air Pollution Emissions Irom Hurning Sugar Cane and Pincapplr from Hawaii. I niv-rsil) of
California. Riverside, (.alif. Prepared for Environmental Protection Agency, Research Triangle Park. N C.
as ameii(iment to Research Grant No. ft8007ll. August 1974.
12. Darley, E. F. el al. Air Pollution from Forest and Agricultural Hurning California Air RfMiurc.-es Board
Projerl 2-0 IT- 1, I'niversilt of (ialifurnia Da\i?.. (Jialif. (^alifurnia Air Resources Board 1'rojei I No. 2-0)7-1.
April 1974.
1'3. Darlev , E. F I'rugress Report on Emissions fmni Agricultural Bunnnp. California Air Hr>ourc<-> Board
Projerl -4-011. I'mversiu of CalilViruia, Riverside, (^alif. Prhale coinmunM'ation uil', pernn-^ion ol Air
ReMiiirre.s Hoard. June I97o.
14. Pnvale c(»nimumcatioii on * -stinialed wn^le production Irom a^nrullural luirnin^ ai in. iiie». ( .alilcir-na \sions I rum Sla>h Hurninj; and the I nllueiin- ol (• lame
Itt-tardani (Jliemii als. J. Air F'ol. Control A*soc . 1?.~> :27H. 197.1.
17. %avne. 1.. (r 3i\'l M 1.. Mi-yuearv. C.ilrnlaliuri ol Emission ha' lor* (or Agrir-nllural Htmiinfi Ac(ivitn»..
Pacific Kn\ in.nrnental Serv n-es. lri< .. Santa Monica. Calif. Prepared lor h.n\ ironinentjl Pmieriion Aijeni \ .
Kei.rari-1) Triangle Park. \ C. under Contract No. f>8-()2-|iX)4, Ta^k Order No. \ PuMii atim, N,, KP^i
J5<) .'{.7.1-087. N'ox ember !97V
5/83 Soliil Waste Disposal
-------
IB. Darlov. F.F. Kn>i»i,iii Karlor |)f\fl<>|imcnl lor l.rul Hum i lift. I MIMM -il\ ol ( jlilnrni.i. Hit cr«iari'»l for Km ironmciUal 1'rolcilion Xpt'in-t. Ni'-currh Tridii^lr I'ark. \.(!.. iimli-r
I'uri haxc 4lnli-r No. ,'>-l)2-ftHT6. 1 . Srpu-mhri 1176.
19. DurlcN. K.K. K\ atiulidii nl' ihc Inijidil til leal HMIIIHI^ - I'li.i^i1 I; l.mi--inn I .icI.ir-IOr Illnliii-
l,r,»\i->. I ni.rr-.ilt ol' ( .'j Jil'oi niu. Ki\rr-iili. (i. hi»lillllc lui
Kiu iriniii
20. SoiitherlHnrl. J.H, anil A. MrHath. F.mi^^iun Factors and Kii-lil Lutxlin^ for Sugar (Iain-
MDAD. OAQPS. I'.S. Emirunmi'ntal Protect iun Ajji'm-). Ri-stMri h Triangle I'ark. \.(i.
1978.
•2.1-to EMISSION FACTORS 5/8S
-------
2.5 SEWAGE SLUDGE INCINERATION
2.5.1 Process Description i-3
Incineration is becoming an important means of disposal for rh» increasing amounts of sludge being produced
in sewage treatment plants. Incineration has the advantages of boll destroying the organic matter present in
sludge, leaving only an odorless, sterile ash, as well as reducing the solid mass by about 90 percent. Disadvantages
include the remaining, but reduced, waste disposal problem and the po'entia) for air pollution Sludge incine*
alien systems usually include a sludge pretreatment stage to thicken and dewatei the incoming sludge, an incinei
ator, and some type of air pollution control equipment (commonly wet scrubbers).
Th- most prevalent types of incinerators are multiple hearth and fluidi/fd bed units. In multiple hearth
units the sludge enters the top of the furnace where it is first dried by contact with the hot, rising, combustion
gases, and then burned as it moves slowly down through the lower healths. At the bottom hearth any residud
ash is then removed. In fluidized bed reacUm, the combustion takes place in a hot, suspended b-il of sand with
much of the ash residue being swept out with the flue gas. Temperatures in a multiple health furnace are 600°F
(320°C) in the lower, ish cooling hearth: 1400 to ?000"F '760 to 1IOO°C) in 'he central combustion hearths,
and 1000 to I200°F (540 to 6SO°C) in the "pper, drying hearths. Temperatures in a fluiJued bed reactor are
fairly uniform, from 1250 to ISOO'F (680 to 82G*CV In both types of furnace an auxiliary fuel may be required
either during startup or when the moisture content of titc sludge is loo high to support combustion.
15.2 Emissions and Controls
Because of the violent upwards movement of combustion gases with respect to i! ? burning sludge, partial
totes are the major emission* problem in both multiple hearth and fluidized bed incinerator? Wet scrubbers are
commonly employed foi paniculate control arid can achieve efficiencies ranging from 95 to 99+ percent.
Although dry sludge may contain from 1 to 2 percent sulfur by weight, sulfui oxides are not emitted in signif-
icant amounts when sludge burning is compared with irnny other combustion processes. Similarly, nitrogen
oxides, because temperatures during incineration do not exceed 1300eF (820°C) in fluidized bed reactors or
1600 to 2000°F (870 to 1100°C) in multiple hearth units, are rot formed in great amounts.
Odors can be a problem in multiple hearth systems as unbi.iied volatiles are given off in the upper, drying
hearths, but are readily removed when afterburntis -are employed. Odors are not generally a problerr in fluid-
ized bed units as temperatures are uniformly nigh enough to provide comolele oxidation of the volatile com-
pounds, Odors can also emanate from the pretieatment stages unless the operations are properly enclosed.
En-.iuion factors for sludge incinerators are sv'wn in Table 2.5-1. It should be noted that most sludge incin-
erators operating today employ some type of scrubber
5/74 Solid Waste Disposal 2,5-1
-------
TABLE 2.5-1. EMISSION FACTORS FOR SEWAGE SLUDGE INCINERATORS3
EHISSION FACTOR RATING: B
Uncontrolled*1
3
C/l
W
0
z
FACTORS
Pollutant
Particulatec
Sulfur dioxide"
Carbon monoxide6
Nitrogen oxide* d (as N02)
Hydrocar bons"
Hydrogen chloride gas
Leadf
After scrubber
Multiple hearth
kg/Mg
50
0.5
Neg
3
0.75
0.75
_
Ib/tou
100
1
Neg
6
1.5
1.5
_
kg/Mg
1.5
0.4
Neg
2.5
0.5
0.15
0.015
(0.01-0.2)
Ib/ton
3
0.8
Neg
5
I
0.3
0.025
(0.02-0.03)
Fluidized bed
kg/Mg Ib/ton
1.5
0.4
Neg
2.5
0.5
0.15
0.001
(0.005-0.002)
3
0.8
Neg
5
1
0.3
0.002
(0.001-0.
003)
aF_,mission factois expressed as weight per unit veiglit of dried sludge. Dash indicates
no data available.
Estimated frou emission factors after scrubbers.
LReferenrea 6-9.
^Reference 8.
eRefrrences 6, 8.
10-11.
ro
•
T
-------
References for Section 2.5
1 . R, R. Calaceto, Advances in Ply Ash Reaoval with Gas-Scrubbing Devices,
Filtration Engineering, J[(7):12-15, March 1970. *
2. 5. Balakriahnan, et al., State of the Art Review on Sludge Incineration
Practices, U.S. Department of the Interior, Federal Water Quality AdninlB-
tratlon, Washington, DC, FWQA-WPC Research Series.
3. Canada's Largest Sludge Incinerators Fired Up and Running, Water and
Foliation Control. ^07(1):2O-21. 24, January 1969.
4. R. R. Calaceto, Sludge Incinerator Fly Ash Controlled by Cyclonic Scrub-
ber, Public Works, 94(2):I13-114, February 1963.
5. I. N. Schuraytz, et al., Stainless Steel Use in Sludge Incinerator Gas
Scrubbers, Public Works 103(2);55-57, February 1972.
6. P. Liao, Design Method for Pluldized Bed Sewage Sludge Incinerators,
PhD. Thesis, University of Washington, Seattle, WA, i972,
7. Source test data supplied by the Detroit Metropolitan Water Departnent,
Detroit, Mi, 1973.
8. Source teat data from Office of Air Quality Planning and Standards, U.S.
Environnental Protection Agency, Research Triangle Park, NC, 1972.
9. Source test data from Dorr-Oliver, Inc., Stanford, CT, 1973.
10. W. E. Davis, Emissions Study of Industrial Sources of Lead Air Pollutants,
1970. EPA APTD-1543, W. E. Davis and Associates, Leawood, KS, April 1973.
1973.
11. Savage Sludge Incineration> EPA-R2-72-040, U.S. Environmental Protection
Agency, Research Triangle Park, NC, August 1972.
2.5-3 So)Id Waste Disposal 12/81
-------
3.0 STATIONARY INTERNAL COMBUSTION SOURCES
Internal conbuaclon engines included in thie category generally are
in applications similar Co those associated with external combustion sources
The major engines within this category are gas turbines and large heavy duty
general utility reciprocating engines. Most stationary internal combustion
engines are used to generate electric power, to pump gas or other fluit's, or
to compress air for pneumatic machinery.
9/85
-------
j. 1 Stationary Gas Turbines for Electric Utility Power Plants
3.1.1 General - Stationary gas turbines find application in electric power generators, in gas pipeline pump and
compressor drives, and in various process industries. The majority of these engines are used in electrical generation
for continuous, peaking, or standby power.1 The primaiy fuels used ^ie natural gas and No .* (distillate) fuel oil.
although residual oil is used in a few applications.
3.1.2 Emissions - Data en gas turbine:, weie gathered and summarized under an EPA contract.2 The contractor
found that several investigators had reported data on emissions from gas turbines used in electrical generation but
that little agreement existed among the investigators regarding the terms in which the emissions Mere expressed.
The efforts represented by this section include acquisition of the data and their conversion to uniform terms.
Because nuny sets of measurements reported tw the contractor were not complete, this conversion often involved
assumptions on engine air flow or fuel flow rates (based on manufacturers' data). Another shortcoming of the
available information w~: Jut relatively few data were obtained ot loads below maximum rated (or base) load.
Available data on 'he population and usage of gas turbines in electric utility power plants are 'airly extensive,
and information from the various sources appears to be in substantial agreement. The source providing the mosi
complete information is the federal Power Commission, which leqimes major utilities (electric revenues of Si
rrn'Hon or more) to submit operating and financial data on an annual basis. Sawyer and Farmer3 employed these
data to develop statistics on (lie use of gas turbines for electric generation in 1971. Although their report inv-lved
only ihe major, publit'iy owned utilities (not the piivaie «v investor-owned companies), the statistics do app.ar lo
include about £7 percent of the gas turbine power used foi electric generation in 1971.
Of the 253 generating stations liMed by Sawyer and Fdrmei, 137 have more than one turbine-gcncr itor unit.
From the available data, it is not possible to know h'>w many houis each lurbins was operated durin, 1971 foi
these- multiple-turbine plants. The remaining I 16 (singk'-turbine) units, however, were operated an average o. 1196
houcr during 147 I (or 13.7 percent of Ihe time), and their average load factc.r (percent of rated load) during
operation was 86.8 percent. This information alone is not dequale for determining n repiescnt: live operating
pjliern for electric utility luitmvjs, but it should help prevent serious errors.
I'sing 1196 hour uf operation per year and 250 starts per yeat a» uuunai, the resulting average operating day is
about 4.8 hcurs, long. One hour of no-load time per day would represent about 21 percent of operating time, which
is considered sonv.-what excessive. For economy considerations, turbines arc not run at olT-d'jsigii conditions any
longev than necessary, bo lime spent at inlenncdiaie power points is probably minimal. The bulk of turbine
operation must be at hast- or peak load tu achieve the high load factor already mentioned.
If it is assumed that li.ne spent at off-design conditions includes 15 percent at zer:> load and 2 percent each a:
25 percent, 50 percCii!, anr) 75 percent load, then the percentages of operating lime a, rated load (100 peicent)
and peak load (assumed to lie 125 pcicent of rated) can he calculated to produce an 8fj.8 percent load factor.
These pirrccntages turn out to be I1) percent a< peak load and 60 percent -j> rated load; the postulated cycle bused
on this line of reasoning is siniimari/cd in Table 3.1-1.
1/75 3.1-1
-------
TabU 3.1-1. TYPICAL OPERATING CYCLE FOR ELECTRIC
UTILITY TURBINES
CorV.ilion.
% «..f rated
power
0
25
50
75
100 (base)
125 (|><;j!\j
Percent operating
time spent
at condition
15
2
2
?
60
19
Time at condition
bared on -i.B-hr day
hours
0.72
0.10
0.10
0.10
2.88
0.91
481
minutes
43
Q
6
6
173
55
289
Contribution to load
'actor at condition
0.00x0 15 = 00
025x002 0.005
0.50 A 0.02 -0.010
0.75 x 002 = 0.015
1.0 .0.60 0.60
1 25
lb/103 gal oil
kg/10J liter oil
Nitrogen
oxides
884
4.01
7.81
3.54
9.60
4.35
412.
6615
67.8
G.13
Hydro
carbons
0.79
0.36
0.7a
0.36
0.79
0.36
42
673.
5.57
0.668
Carbon
Monoxide
2 18
0.99
2.18
0.99
2.18
0.99
115.
1842.
15.4
1.8b
Panic-
ulate
052
0.24
0.27
0.12
0.71
0.22
14.
224
5.0
0.60
Sulfur
oxides
0.33
0.15
0.098
0.044
0.50
0.23
910S1'
15,0005
140S
16.8S
)* th« (actor it 9aO .nd ihi iul>jr content hi 0.01 p«rc«fit, th« tuKur oxide* (mined wo'jld
Mated load expressed in megawaiti
°r» )• 1h« parearnag* f uHur. ExarTP'f
b« B40 timn 0.01, or P.4 IbMO6 T
Table 1.1-2 is trie rcsullani composite emission factors hdseu on the operating cytiL- of Table!). 1 -1 and ihc
1971 population of electric utiliiy turbines.
EMISSION FACTORS
1/75
-------
Di!!einii values I'ui inuc ji base und peak lo-jds jie obtained by Jumping the total linn- jt lower loads (0
ll'iiuiph 75 percent) or by cliJii^iiiji the distribution n1 jinx; spent .it loufi loads. The cycle given in Table 3. )-l
seems reasonable, howevei. •.•oiisiOerng ihc fixed lujj fjnor anil ilie cci)t)o:iiK'\ 01 iiuhine operjiion. Note thai the
L'\C!C dcioiiniiK's ,'///> tin. MViptn:uncc of cucli load condition in coinpiiting compusiio cniiisiiin (jclurs for fjc,h
type of turbine, not overall updating houis.
Tlie lop portio.i o-'Table 5.J-2 gives iepjuli; (jclois I'oi ^ji-lux-d aiul uil-'ircd niuu.jiid the noiloin portion
give) iWI-b-iscd Ijtiois that car be used U> oiinriic ciui^sio.i luu'.s M.ICII overall ti.^'l consuniption c'uiu JIL*
avjibbk-. hiu-|-n:i!>t'd omission factors on a mode RUMS would al..i hi1 useful bin present lucl consumpiion dalj are
noi adequate lor this pui(>osi-
References for Station 3.1
I. O'KcCK-. W. and R.G.Sclmicnei. P.inv MOMMS. I'owc:. /.'.?('! ' 5:2-5.? I. November I'I'M.
2. ILiv, ('. T. and K. i. Sprinjiei. i \luubi l-.inissiom from (!in;i/ntrolleJ Vehicles aiic Rel.-iii'd Lquipnioiu Using
Intciiul (".»inbi,".!;oii l.npinc>. I iiul Report. PUM (>: Cijs T nhiue l-locirk1 I'lilils I'owet Plains Southwest
Research :nsli!'.ne. Sun Anionin. lc.\. 1'ieparcd lor l-.iivn^xinenl.il Piolcction A(!cncy. Rcseaich Triuii(ili: Pjik.
N T., unt'ifr Cimiracl No KHS 7('-lfJ>*% I ••hruary ll>74
3. Sawvei, V. W. and R. C. Fanner. GJS Turbines in U.S. KkYiric I'tilities. Gas Turbine Intcrnaiionjl. Jaiuiaiy ••
April I<)7.V
1/75 3.1-3
-------
3.2 Heavy Diicy Natiral Gas Fired Pipeline Compressor Engines
3.2.1 Genera]1 - Engines in the natural gas industry are used primarily to power compressors used for pipeline
transportation, Held gathering (collecting gas frc.n wells), underground storage, and gas processing plant
application*. Pipeline ennir.es aie concentrated ir. the major gas producing states (such as those along the Gulf
Coast) and along thr major gas pipelines. Both reciprocating engines and gas turbines are utilized, but the trend
has been toward use or large gas turbines. Gas turbines emit considerably fewer pollutants than do reciprocating
engines; however, reciprocating engines are generally more efficient in 'heir ose of fuel.
3.2.2 Emissions and Controls1 >2 - The primary pollutant of concern is NOX, which readily forms in the high
temperature, pressure, and excess air environment found in natural gas fired compressor engines. Lesser amounts
of carbon monoxide and hydrocarbons are emitted, a-though for each unit of natural gas burned, compressor
engines (particularly reciprocating engines) emit significantly more of these pollutants than do external
combustion boilers. Sulfur oxides emissions are proportional to the sulfur content ol the fuel and will usually be
quite low because of the negligible sulfur content of most pipeline gas.
The major variable* affecting N0j< emissions from compressor engines include the ur fuel ratio, engine load
(defined is the ratio of the operating horsepower divided by the rated horsepowtr), intake (manifold) air
temperature, and absolute humidity In general, NOX emissions increase with injecting load and intake air
temperature and decrease witti increasing absolute humidity and aiv fuel ratio. (The latter already being, in most
compressor engines, on the "lean" side cf that air fuel ratio at which maximum NOX forr\ation occurs.)
Quantitative estimates of the effects of these variables are presented in Reference 2.
Because NOX is the primary pollutant of significance emitted from pipeline compressor engines, control
measuies to date have been directed mainly at limiting NOX emissions. For gas turbines, the most effective
method of controlling NON emissions is the injection of water into tht combustion chamber. Nit ogen oxides
reductions as high as 80 |>ercent can bt achieved by this method. Moreover, water Injection results in only
nominal reductions in overall turbine efficiency. Steam injection can also be employed, but the resulting NC^
reductions mi\y not be as grett as with water injection, and it has the added disadvantage thai «i supply of steam
must be read jy available. Exhhust gas recirculation. wherein a portion of the exhaust gases is rcjirculated back
into (he intake manifold, nay result ;n NOX reductions of up to SO percent. This techr.^je. however, may not be
practical in nany cases because the recircularcd gases must be cooled to prevent engine malfunction. Other
combustion modification >, designed to redui, the temperature and/or residence unie of the combustion gases,
can also be effective in reducing NOX emissions by 10 to 40 percent in specific gas turbine units.
For reciprocating gas-fircd engines, the most effective NOX control measures are those that change the air-fuel
ratio. Thus, changes in engine torque, speed, intake air temperature, etc., that in turn increase the air-fuel ratio,
rm- all result in lover NOX emission'.. Exhaust gas iv '.rculation may also be effective in lowering NOX emissions
although, as with turbines, there arr practical limits because of the large quantities of exhaust gas that must be
cooled. Available data suggest that other NOX control measu.es, including water and steam injection, have only
limited application to reciprocating g.'s fred entries.
Emission factors for -uiuial gas fired pipeline compressor engines are presented in Table 3. 2-1,
4/76 3.2-1
-------
Table 3.2-i. EMISSION FACTORS FOR HEAVY CITY NATURAL
GAS FIRED PIPELINE COMPRESSOR ErVQINES1
EMISSION FACTOR RATING: A
Reciprocating engines
lb/103hp-hr
B/'ip-hr
9/kW-hr
Ib/IO^jcf'
kg/IO6!*™3*
GCJ turbines
Ib/IO^p-hc
g/hp-hr
gAW-hr
lb/10® icfl
kgyiQ«Nm3fl.
Nitrogen oxides
(as N02)b
24
11
IB
3,400
55,400
2.0
1.3
1.7
300
4.700
Cat Inn
monoxide
3.1
1.4
1.9
430
7,020
1.1
0.6
0.7
120
1.940
Hydrocarbons
'as C)c
9.7
4.4
5.8
1,400
21,800
0.2
0.1
0.1
23
280
Sulfur
dioxide11
0.004
0.002
o.oc;
0.6
9.2
0.004
0.002
0.003
0.6
9.2
P.irticu'ate8
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
'All lector* baaed on Reference* 2 and 3.
bTneee factor* are for compreator engine* cpjratad el rated load. In general, NOX aminion* will increete with increasing
load and intake (manifold) air temperatMre end decree** with increating air-fuel ratioi lexcet* rlr rate*) and afaaolute
humidity. Quantitative eailmata* of the effect* of thee* veriebta ere preeuntad in Referent; 2
'Theee factor* repteeent total hydrocarbon*. Normpthan* hydrocarbon* are eatimated to make up to 5 to 10 percent of
theae total*, or the average.
dB«ied c it
not fired, a materiel balance thould be performed to determin* SOj •niasion; bated on the actual tulfur conient.
*Not available Ir'-m axuting data.
'Theae factor* ere &»l udated from the above factor* lor reciprocating engine* etaunning B heating value of 1050 Btu/«cf
(9360 kcel/Nrrt^t foi r ituraJ gas and an average fuel consumption of 7500 Btu/hp-hr (2630 kcal/kW-hrl.
ate factors are calculated from the above factor* for gti turbinat aouming a heating valut of 1,060 Btu/acf (9,350 keel/
n') of natural gel and an average fuel coneumption of 10,000 Btu/hp-hr (3,380 kcal/kW-hr).
°Th
N.
References for Section 3.2
1. Standard Support Document and Bn/ironmental Inpact Statement - Stationary Reciprocating Internal
Combustion E.igines. Aerothenn/Arurex Corp., Mountain View, Calif. Prepared for Environmental Protection
Agency, Rewarch Triangle Park, N.C. under Conliact No. 68-C2-1318, Task Order No. 7, November 1974.
2. Urban, C.M. and KJ. Springer. Study of Exhaust Emissions from Natural Gas Pipeline Compressor Engines
Southwest Research Institute, San Antonio, Texas, Prepared for American Gas Association, Arlington, Va.
February 1975.
3. Dietzmann, H.b. and K J Springer. F\haus» Emissions from Phlon and Gas Turbine Engines Used in Natural
Gas Transmission. Southwest Resean n Institute, San Anton'o, Texas. Preparrd for American Gas Association,
Arlington, Va. January 1974.
3.2-.?
EMISSION FACTORS
4/76
-------
3. 3 Gasoline and Diesel Industrial Engines
3. j.l (JeiHr.ii Thi* engine category covers a wiiie variety i>i industrial applications oi both gasoline and diescl
internal oornhustiun ,H>44. kW (45 to 600 lip) for diesel engines.
UnderstandaKly, substantial differences in both annual usajie (iiuurs per y ^-r); id engine iJaty cycles also exist. It
wjs necessary, thcietoic, to make reasonable iissLinpiuiiib, ^onccnunj; un the basis of "brake specific" emission factors fg/' Wh or
Ib/hphr). Emissions arc calculated by liking the product of the brake specific emission factor, ML- ui ;e in hours
(that is, houis per year 01 hours per day), the power available (rated power), . nd the load factor (the power
actually usrd divided by the power available).
Table 3.3-1. EMISSION FACTORS FOR G«kSOLINfc
AND DIESEL POWERED INDUSTRIAL EQUIPMENT
EMISSION FACTOR RATING: C
Pollutant3
Cartion none xide
g hr
iJ/hr
i/'kWh
• l/hphr
kg/103 liter
Engine category"
Gasoline
5700.
12.6
267.
199.
472.
'bMQ1 gal ; 3340.
Exnaust hydrocarbons
()/hr
Ib/hr
g/kWl
g/hphr
kg/ 10' liter
tb/10'1 gal
Evjf.orativ/e hydrocarbons
g/hr
Ib/hr
Crankcase hydrocr.rbur.s
g/hr
lu/hr
191.
0.421
895
6.68
158
132.
62.0
0.137
38.3
C.084
Diesel
197.
0.434
4.06
3.03
122
102,
72.8
0.160
1 50
1.12
4.49
3/.5
-
-
_
—
1/75
3.3-1
-------
Table 3. 3-1 (continued). EMISSION FACTORS FUR GASOLINE
AND DIESEL POWERED INDUSTRIAL EQUIPMENT
EMISSION FACTOR RATING: C
Pollutant3
Nitrogen oxides
g/nr
Ib/hr
g/kWh
g/hphr
kg/103 lite,"
lb'10J gal
Aldehydes
g/hr
lo/hr
y/kWh
g/hphr
kq/101 hler
lb/10' gal
Sulfur oxides
g/hr
Ib/hr
g/kWh
g/hphr
kg/10'1 liter
lb/10-' gal
Part icu late
g/hr
Ib/hr
g/kWh
g/hphr
kg/101 liter
lb/10' gal
fcngine catcqory°
Gasoline
148.
0.326
6.92
5.16
122
102.
6.31,
0.014
030
0.22
0.522
4.36
7.67
0017
0.359
0.268
0.636
5.31
9.33
0.021
0439
0.327
0.775
647
Diesel
910
201
188
140
56.2
469.
13.7
0.030
0.28
0.21
0.64
7.04
60.5
0.133
1.25
0.931
3.7<«
31.2
650
0 143
1.3-5
1.00
4.01
33.5
References I and 2
As discussed in the lexl, the engines used to determine the results ;n this
table tover a widr 'inge of uses and Bovver. The (isied values do not.
however, recessanlv applv to some wery 'argt siaiioiary diesci • nymes.
References for Srctior. 3.3
I. Hare, C. T. and K. J. Springer. Lxhaust Emissions Ironi l.'ncon'iollcd Vehicles and RoijHd [{quipmont Using
Internal Comhujtion Engines. Final Rcpoil. Pan 5: Heavy-Duty Farm, Conslruc'ion. j id Indiibirial Hnginos.
Souiliwest Research Instnute. San Anii-nio. TCXJS. Prepared for Environmental P.i.ii'ciion Agciu'y. Rcscaich
Triangle Park, N.C . under Contrucl No. hUS 70-108. October 1()73 IDS p.
2. Hare, C. T. Letter to C. T. Musscr oi the linvironnicnial Protection Agency coiucrniug fucl-hnsc ; emission
r, tes for (arm, construction and industrial engines. Sjn Amoniu. Tex. Janujry I4,lc)74.
3.3-2
EMISSION FACTORS
1/75
-------
3. 4 STATIONARY LARGE BORE DIESEL AND DUAL FUEL ENGINES
3.4.1 General
The primary dome a tic use of large bore diesel engines, i.e., those
greater than 560 cubic inch displacement per cylinder (CID/CYL) , is in oil
and gas exploration and production. These engines, in groups r/' hree to
five, supply mechanical power to operate drilling (rotary table. iud pump-
ing and hoisting equipment, and may also operate pumps or auxil • power
generators. Another frequent application of large bore diesels .o elec-
t'icity generation for both base and standby service. S'naller uses include
irrigation, hoisting and nuclear tower plant emergency cooling water pump
operation.
Dual fuel engines were developed to obtain compression ignition
performance and the economy of natural gas, using a minimum of 5 to 6 percent
dieael fuel to ignite the natural gas. Dual fuel large bore engines (greater
than 560 CID/CYL) have been used almost exclusively for prim* electric power
generation.
3.4.2 Emissions and Controls
The primary pollutant of concern fram lavge bor= diesel and dual fuel
engines is NOx, which readily fr>n,
-------
TA^LE 3.4-1. EMISSION FACTORS FOR STATIONARY LARGE BORE DU.SEL
AND DUAL FUEL ENGINES*
HM1SSLON !• ACTOR RATING: C
1
Engine type
Diesel
lb/103 hph
g/hph
g/kwh
lb/103 g«)f
«A
Dual fuel
lb/103 hph
|/hph
g/ktfti
Partlculate*1
2. 4
1.1
1.5
50
6
MA
HA
NA
Nitrogen
o«ide«c
24
11
13
300
bO
16
e
11
Carbon
BonoKlde
6.4
2.9
3.9
110
16
3.9
2.7
j.6
VOC*1
Methane
0.07
0.03
0.04
1
0.2
A./
2.1
r..9
Nona* thane
0.63
0.29
0.4
13
1.6
1.3
0.7
0.9
Suliur
dioxide8
2.0
1.3
1.7
60
7.2
0.70
0.92
0.43
i '
•Representative uncontrolled level* fur each fuel, determined by weighting -lite froa
•averul manufacturer*. Weigtiiing b".»«d on Z or tor.al horcapowar told by each Manu-
facturer during a fi/a year period. NA - not available.
factor Latlng: 8. ApproxlBatlon baiad an tatt of a aadlua bora dlnal.
«rr. BlnlauB expected for engine operating at 50 - 100Z full rated lead.
At OZ load, ealetloot* would increaaa to 30 g/1. Reference 2.
cMeaiured aa NOj. Factora are for cnglnea operated at rated load and ipeed.
dNona«thaij« VOC ia 90Z of total VOC ft OB dleael englnea but only 23S of total VOC
mietlona froai dual fuel eoglnee. Individual chemical apeciaa within the non-
•ethane fraction are not identified. Molecular weight of nonBath'.iM |aa atraaa ia
aaauaad to be that of Bathene.
•Baaad on eieuBcd aulfur coatent of 0.4 weight Z for dleael fuel and 0.46 g/ic»
(0.20 gr/acf) for pipeline quality natural &ae. Dual fuel SOj eailaalona baaad on
3* oil/951 gaa •!•. Emiiaioni ahould be adjueted for other fuel racVoe.
flheee factora calculated from the above factor*, aeeuning heating valuea of 40
NJ/1 (145,000 Bta/gal) for oil and 41 MJ/au (1100 Btu/arlj for natural gaa, and
an average fuel conauaptlon of 9.9 MJ/kUh (7000
References for Section 3.U
1• Standards Support And Environmental Impact Statement, Volume I:
Stationary Internal Combustion Engines, EPA-450/2-78-125a, U.S.
Environmental Protection Agency, Research Triangle Park, NC, July 1979.
2. Telephone communication between WJlli.am H. Lamaaon, Office Of Air
Qualify Planning And Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC, and John H. Wasser, Office Of Research And
Development, U. S. Environmental Protection Agency, Research Triangle
Park, NC, July 15, 1983.
3.4-2
EMISSION FACTORS
8/84
-------
4. EVAPORATION LOSS SOURCES
Evaporation losses include the organic solvents emitted from
dry cleaning plants and surface coating operations, and the volatile
matter in petroleum products. This chapter presents the volatile
organic emissions from these sources, including liquid petroleum
storage and marketing. Where passible, the effect is shown of
controls to reduce the emissions of organic compounds.
4.1 DRY CLEANING
4.1.1 General1'2
Dry cleaning Involves the cleaning of fabrics vith nonaqueous
organic solvents. The dry cleaning process requires three steps:
(1) washing the fabric in solvent, (2) spinniig to extract excess
solvent and (3) drying by tumbling in a hot air stream.
Two general types of cleaning fluids arc; used in the industry,
petroleum solvents and synthetic solvents. Petroleum solvents,
such as Stoddard or 140-F, are inexpensive combustible hydrocarbon
mixtures similar to kerosene. Operations using petroleum solvents
are known as petroleu: plants. Synthetic solvents are nonflammable
but more expensive halogenated hydrocarbons. Perchloroethylene and
trichlorotrifluoroethane are the t"o synthetic dry cleaning solvents
presently in use. Operations using these synthetic solvents are
respectively called "pare" plants And fluorocarbon plants.
There are two basic types of dii; cleaning machines, transfer
and dry-to-dry. Transfer machines accompHah washing and drying in
separate machines. Usually, the washer extracts excess solvent
from the clothes before they are transferred to the dryer, but some
older petroleum plants have separate extractors for this purpose.
iKy-to-dry machines are single units that perform all of the washing,
extraction and drying operations. All petroleum solvent machines
are the transfer type, but synthetic solvent plants can be either
type.
The dry cleaning industry can be divided into three sectors,
coin operated facilities, commeicial operations and industrial
cleaners. Coin operated facilities are usually part of a laundry
supplying "self-service" dry cleaning for consumers. Only synthetic
solvents are used j.n coin operated dry cleaning machines. Such
machines are small, with a capacity of 3 6 to 11.5 kg (8 to 25 Ib)
of clothing.
4/81 Evaporation Loss Siiuro.es
-------
M
o
2
•«J
q
C
OC
EXHAUST GAS/Sm.VEMT
HEATED
WATER-
DETERGENT
DRYER
H
CONDENSER
SOLVENT
SEPARATOR
WATER
WATER
HEAT .
(DISOWTION!
CARBON
ADSORBER
•DESORBEDSOLVENT
• AND STEAM
MUCK
COOKER
MUCKl
MUCK
GASES
SOLVENT
EMISSIONS
CONDENSER
OISPOSAL
DISPOSAL
WATER
Figure 4,1-1. Perchloroethylene dry cleaning plant flow diagram.
-------
Commercial operations, such as small neighborhood or franchise
diy cleaning shops, clean soiled appar«>l for th.j consumer. Generally,
perchloroethylene and petroleum solvents are used in conmer:ial
operations. A f.ypical "perc" plant operates a 14 to 27 kg (30 »o
60 Ib) capacity washer/extractor and an equivalent size reclaiming
dryer.
Industrial cleaners are larger dry cleaning plants which
supply rental service of uniforms, mats, mops, etc., to businesses
or industries. Perchloroethy l«?nc Ls used by approximately 50 percent
of the industrial dry cleaning establishments. A typical large
industrial cleaner has a 230 kg (bOO Ib) capacity washer/extractor
avid three >o six 38 kg (LOO Ib) capacity dryers.
A typical perc nlant is shown in Figure 4.1-1. Air hough one
solvent tank may bp used, :he typical perc plant used two tanks for
washing. One tank contains pure solvent, and the other contains
"charged" solvent (used solvent to which small amounts of detergent
have been added to aid in cleaning). Generally, clothes are cleaned
in charged solvent and rinsed in pure solvent. A water bath may
also be used.
After the rlothes have been washed, the used solvent is filtered,
and part of the filtered solvent Ls returned to the charged solvent
tank for washing the next load. The remaining solvent is then
distilled to remove oils, fats, greases, etc., and is returned to
the pure solvent tank. The resulting distillation bottoms are
typically stored on the premises until disposed of. The filter
caki and collected solids (muck) are usually removed from the
filter once a day. Before disposal, tuo mu^.k. may be "cooked" to
recovp.r additional solvent. Still and n.uck cookei vapors are
vented to A condenser and separator, where more solvent is reclaimed.
In many perc plant", tlie condenser offRases are vented to a carbon
adsorption unf.t for additional solvcat. recovery.
After washing, thp Clothes are transferred to the dryer to be
tumbled in a h-jaled air stream. Exhaust gases from the dryer,
along with a smi.ll amount of exhaust gases from the washer/extractor,
are vanted to a water cooled condenser and water separator.
Recovered solvent Is returned to the pure solvent storage tank. In
30 to 50 percent of the perc plants, the condenser offgases are
vented to a carbon adsorption unit for additional solvent recovery.
To reclaim this solvent, the unit must he periodically .iesorbod
with st'iair., usually at the end of each day, Desorbed S3lvent and
water are condensed and separated, and recovered solvent is returned
t'.- the pure solvent tank.
A petroleum plant would differ from Figure 4.1-1 chiefly in
that there would be no recovery of solvent fro.ti the washer and
dryer and no muck cooker. A fluorocarbon plant would differ in
that an unvented refrigeration system would be iiBed in place of a
carbon adsorption unit. Another difference is that a typical
4/81 Evaporation Loss Sources 4.1-3
-------
fluorocarbon plant could use a cartridge filrer which id drained
and disposed of after several hundred cycles.
Eaissions and Controls
The solvent itself is the primary emission from dry cleaning
operations. Solvent is given off by washer, dryer, solvent still,
muck cooker, still residue and filter muck storage areas, as well
as by leaky pipes, flanges and pumps.
Petroleum plants have not generally employed solvent recovery,
because of the low cost of petroleum solvents and the fire hazards
associated with collecting vapors. Soms emission control, however.
can be obtained by maintaining all equipment (e.g., praventing lint
accumulation, solvent leakage, etc.) and by using good operating
practices (e.g., not overloading machinery). Both carbon adsorption
and Incineration appear to be technically feasible controls fcr
petroleum plants, but costs are high.
Solvent recovery is necessary in pcrr plants due to the higher
cost of perchloroethylene. As shown In Figure 4.1-1, recovery Is
effected on the washer, dryer, still and muck cooker through the
use of condensers, water/solvent separators aad carbon adsorption
units. Typically once a -iay, solvent in the carbon adsorption unit
is desorbed with steam, condensed, separated from the condensed
water and returned to the pure solvent storage tank. Residual
solvent emitted from treated distillation bottoms and muck is not
recoveredi As in petroleum plants, good emission control can be
obtained by gooH housekeeping (maintaining all equipment and using
good operating practices).
All fluorocarbon machines are of the dry-to-dry variety to .
conserve solvent vapor, and all are closed systems with built In
solvent recovery. High emissions can occur, however, as a result
of poor maintenance and operation of equipment. Refrigeration
t/stems are installed on never machines to recover solvent from the
washer/dryer exhaust gases.
Emission factors for dry cleaning operations are presented in
Table 4.1-1.
, Typical coin operated and commercial plants emit less than
10 grams (one ton) per year. Some applications of emission estimates
are too broad to identify every small facility. For estimates over
large areas, the factors in Table 4.1-2 may be applied for coin
operated and commercial dry cleaning emissions.
4.1-4 EMISSION FACTORS 4/81
-------
oo
V
1}
o
r-1
to
ts>
o
c
1
c,
A
01
TABLE 4.1-1. SOLVENT LOSS MISSION FACTORS FOR DRY CLEANING OPERATIONS
MISSION FACTOR RATING: B
Emission Rate
Solvent Type
(Process uii-i
Source
Typical systt
kg/100 kg (JK/IOU Ib)
He 11 controt ted ayetea
kg/I00 k-f, (ib/lOO lh)
Petroleum
(transfer pror«"g«O
Percliloroethylene
(transfer process)
Tr IchlorotrIfluoroelhane
(dry-tu-dry procens)
wander/dryer
Filter disposal
uncooked (drained)
centrtfuged
nlll I residue .disposal
iitacel laneous
filter disposal
uncooked Muck
conked Buck
cartridge Filter
still residue .disposal
Miscellaneous
washer/dryer/st ilI
cartridge Fitter d
•till residue.disposal
miscellaneous
IB
a
al I
1
uck cooker fl
14
1.3
I.I
al 1.6
1.5
0
posx1 1
al 0.5
1 - 3
0.5 -
0.5 -
1
o.ic
0.5 -
0.5 -
0.5 -
1
0
1
0.5
1 - 3
1
1
1.3
1.1
1.6
"References 1-4. Units ate In term of weight nolvent per weight of clothed cleaned (capt*clt, n londa).
Erotflntonn also may b«- °9tl»at^i by determining the flnount of solvent cnnguned. Assuming that all
solvent Input 10 eventually evaporated to the atmosphere, an emission Factor oF 2000 Ih/ton (1000 kg/!!g)
.of nolvent conRumed can he applied.
Different ran tar la I in wash --tains a different aoount of solvent (synthetics. 10 kg/100 kg; cotton,
20 kg/100 kg; leather. 40 kg/100 kg).
^BalnsLonn Froa washer, dry?r. still and ouck cooker are passed collectively through a carbon ndsorber.
Hlgcellaneoiia sources include Fugitives From Flanges, puvps, pipes and storage tanks, and f'.xed loa«»a
aucli as opening and closing dryera, etc.
*Uncnntrolled enlssloiiR FroB wanher, dryer, still and Muck cooker average about fl kg/100 kg (8 lh/100 Ib).
fAbout IS? of solvent emitted Is Fr;i« washer. 75X dryer. 5Z each from still and Buck cooker.
"Based on the typical lefrlgerallon syntc* Installed In fluorocarbon plants.
-------
TABLE 4.1-2.
FACTORS
PER CAPITA SOLVENT LOSS EMISSION
FOR DRY CLEANING PLANTS
EMISSION FACTOR RATING: B
Emission Factora .
Operation kg/yr/caplta g/dsy/capita
(Ib/year/cap) (lb/day/cap)
Commercial
Coin operated
0.6
(1.3)
0.2
(Q.4)
1.9
(0.004)
0.6
(0.001)
.References 2-4. All nonmethaue VOC.
Assumes a 6 day operating week (31 "3 days/yr).
References for Section 4.1
1, Study To Support New Source Performance Standards for the
Dry Cleaning Industry, EPA Contract No. 68-02-1412, TRW, Inc.,
Vienna, VA, Hay 1976.
2. Perchloroethylene Dry__Cleanera - jackground Information for
Proposed Standards. EPA-450/3-"'9-029a, U.S. Environmental
Protection Agency, Research Triangle Park, NC, August 1980.
3. Control of Volatile OrganicEmissions Crom Perchloroethylene
Dry Cleaning Systems, EPA-450/2-7S-050, U.S. Environmental
Protection Agency, Research Triangle Park, NC, December 1978.
4. Control of Volatile Organic Emissions from _P_e_troleum Dry
Cleaners __(_D_raf *.), Office of Air Quality Planning and Standards,
U.S. Environmental Protection Agency, Research Triangle Park,
NC, February 1981.
4.1-6 EMISSION FACTORS 4/81
-------
4.2 SURFACE COATING
Surface coating operations Involve the application of paint, varnish,
lacquer or paint primer, for decorative or protective purposes. This is
accomplished by brushing, rollings, spraying, flow coating and dipping oper-
ations. Some Industrial surface coating operations Include autocioblle assembly,
job enamellig, and manufacturing of aircraft, containers, furniture, appliances
and plastic products. Nonindustrial applications of surface coatings Include
automobile reflnlshlng and architectural coating of domestic, Industrial,
government and Institutional structures, Including building interiors and
exteriors and exteriors and signs and highway markings. Nonlndustrlal Surface
Coating Is discussed below In Section 4.2.1 , and Industrial Surface Coating
In Section 4.2.2.
Emissions of volatile organic compounds (VOC) occur In surface coating
operations because of evaporation of the paint vehicle, thinner or solvent
used to facilitate the application of coatings. The major factor affecting
ther.e emissions is the amount of volaHle matter contained In the coating.
The volatile portion of most common surface coatings averages about SO per-
cent, and most, If not all," of this Is emitted during the application of
roatlngs. The major factor affecting these emissions Is the amount of
volatile matter contained In the coating. Tht volatile portion of roost com-
mon surface coatings averages about 50 percent, and most, If not all, of this
Is ' it ted during the application and drying of the coating. The compounds
releas d include aliphatic and aromatic hydrocarbons, alcohols, ketones,
esters, alkyl and aryl hydrocarbon solvents, and mineral spirits. Table
4.2-1 presents emission factors for general surface coating operations.
TABLE 4.2-1. EMISSION FACTORS FOR GENERAL SURFACE COATING APPLICATIONS3
EMISSION FACTOR RATING: B
Coating Type
Paint
Varnish and Shellac
Lacquer
Enamel
Primer (zinc clirouate)
ype
e)
Emissions^
kg/Mg
560
500
770
420
660
Ib/ton
1120
1000
1540
840
1320
aRijference 1.
Reference 2. Noiune thane VOC.
References for Section 4.2
1. Products Finishing, 4J.(6A) :4-54, Marc'i 1977.
2. Air Pollution Engineering Manual, Second Edition, AP-40, U. S.
Environmental Protection Agency, Research Triangle Park, NC, May 1973,
Out of Print.
4/81
Evaporation Loss Sources
4.2-1
-------
4.2.1 NONINDUSTRIAL SURFACE COATING
1,3,5
Nonindustrlal surface coating operations aro aonroanufacturlng
applications of surface coating. Two major categories are architectural
surface coating and automobile re finishing. Architectural uses are
considered to Include both Industrial and nonindustrial structures.
Automobile reflnlshing pertains to the painting of damaged or worn
highway vehicle finishes and not the painting of vehicles during
manufacture.
Emissions from a single architectural structure cr automobile
refinishing are calculated by using total volume and content and
weight of volatile constituents for the coating employed In the
specific application. Estimating emissions for » large area which
includes many major and minor applications of nonlndustrLai surface
coatings requires that area source estimates be developed. Archi-
tectural surface coating and auto refinlahing emissions data are
oftei difficult to compile fur A large geographical area. In cases
where a large Inventory is being developed and/or resources are
unavailable for detailed accounting of actual volume of coatings
for these applications, emissions may be assumed proportional to
population or number of employees. Table 4.2.1-1 presents factors
from national emission data and emissions per population or employee
fur architectural surface coating and automobile reflnlshing.
TABLE 4.2.1-L. NATIONAL EMISSIONS AND EMISSION FACTORS
FOR VOC FROM ARCHITECTURAL SURFACE COATING
AND AUTOMOBILE REKINISHING
EMISSION FACTOR RATING: C
Emissions
National
Mg/yr
ton/yr
Per capita
kg/yr (Ib/yr)
g/day (Ib/day)
Per employee
Mg/yr (ton/yr)
xg/dey (Ib/day)
Architectural Surface
Coating
446,000
491,000
21.4 (4.6) .
5.6 (0.013)
-
Automobile
Reflnlshing
181.000
199,000
O.S4 (1.9)
2.7 (0.006)
2.3 (2.6)
7.4 (16.3)
References 3 and 5-8. All nonmethane organlcs.
'Reference 8. Calculated by dividing kg/yr (Ib/yr) by 365 days and
converting to appropriate units. Assumes that 75% of annual
emissions occurs over a 9 month ozone season. For shorter ozone
seasons, adjust accordingly.
Assumes a 6 day operating week (313 days/yr).
4/81
Evaporation LOBS Sources
4.2.1-1
-------
The ube of waterbo me architectural coatings reduces volatile
organic compound emissions. Car re at. consumption trends indicate
increasing substitution of waterborne architectural coatings for
those using solvent. Automobile refinishing often is done in areas
only slightly enclosed, which makes control of emissions difficult.
Where automobile refinishing takes place Ln an enclosed area,
control of the gaseous emissions can be accomplished by the use of
adsorbers (activated carbon) or afterburners. The collection
efficiency of activated carbon has been reported at 90 percent or
greater. Water curtains or filler pads have little or no effect on
escaping solvent vapors, but they are widely used to stop paint
particulate emissions.
References for Section 4.2.1
1. Air PollutionEngineering Manual, Second Edition, AP-40, U.S.
Environmental Protection Agency, Research Triangle Park, NC,
May 1973. Out or Print.
2. Control Techniques for Hydrocarbon and Organic Gasesfrom
Stationary Sources, AP-68, U.S. Environmental Protection
Agency, Research Triangle Park, NC, October 1969.
3. Control Techniques Guideline for Architectural jiurface Coatings
(DraEt), Office of Air Quality Planning and Standards, U.S.
Environreental Protection Agency, Researcn Triangle Park, NC,
February 1979.
4. Air Pollutant Emission Factors, HKW Contract No. C?A-22-69-119,
Resources Research Inc., Reston, VA, April 1970.
5. Procedures for the Preparation of Emission Inventories for
Volatile Organic Compounds, Volume I, Second Edition,
EPA-450/2-77-028, U.S. Environmental Protection Agency, Research
Triangle Park, NC, September l^GO.
6, W.H. Lamason, "Technical Discussion of Per Capita Emission
Factors for Several Area Sources of Volatile Organic Compounds",
Monitoring and Data Analysis Division, U.S. Environmental
Protection Agency, Research Triangle Park, NC, March 15, 1981.
Unpublished.
7. End Use of Solvents Containing Volatile Organic Compound;},
EPA-450/3-79-032, U.S. Environmental Protection Agency, Research
Triangle P.-irk, NC, May 1979.
8. Written communications between Bill Lamason and Chuck Mann,
Monitoring and Data Analysis Division, U.S. Environmental
Protection Agency, Research Tiiangle Park, NC, October 1980
and March 1931.
4.2.1-2 EMISSION FACTORS 4/81
-------
9. /inalBalsalop Inventory Requireaeotafor 1962 Qgone State
lapleaentatioo Plena. BPA-A50/U-90-016. U.S. EavirotMeoteT
Protection Agency, Research Triangle Perk, NC, Deceaber 1980.
4/61 Evaporation LOBB Source* 4.2.1-3
-------
4.2.2 INDUSTRIAL SURFACE COATIHG
4.2.2.1 GRNERAL INDUSTRIAL SURFACE COATING1-4
Process Description - Surface coating la the application of decorative or
protective aateriala in liquid or powder form to substrates. These coatings
normally Include general BO 1vent type palnta, varnishes, lacquera and water
thinned paints. After application of coating by one of a variety of methods
such ae brushlug, rolling, spraying, dipping and flow coating, the surface is
air and/or heat dried to remove the volatile solvents from the couted surface.
Powder type coatings can be applied to a hot surface or can be melted after
application and caused to flow together. Other coatings can be polymerized
after application by the»-aal cut?ng with Infrared or electron ueam aysteas.
Coating Operations - There are both "coll" ("Independent"! and "captive"
surface coating operations. Toll operations fill orders to various manufac-
turer specifications, and thus change coating and solvent conditions more
frequently than do captive companies, which fabricate and cott products within
a single facility and vhlch mav operate continuously with thi same solvents.
Toll and captive operations differ In emission control systems applicable to
coating lines, because not all controls are technically feasible In toll
si tuaMons.
Coating Formulations - Conventional coatings contain at least 30 volume
percent solvents to permit «asy handling and application. They typically con-
tain 70 to 85 percent solvents by volume. These solvents may be of one com-
ponent or of a mixture, of volatile ethers, acetates, aroma tics, cellosolves,
aliphatic hydrocarbons and/or water. Coatings with 30 volume percent of
solvent or less are called low solvent or "high solids" coalings.
Waterborne coatlnga, which have recently giined substantial use, are of
several types: water emulsion, vaver soluble and colloidal dispersion, and
ele<-trocoat. Common ratios of vater to solvent organlcs In emulsion and dls-
oerslon coatings are 80/20 and 70/20.
Two part catalyzed coatings to be dried, powder coatings, hot melts, and
radiation cured (ultraviolet and electron beam) coatings contain essentially
no volatile organic compounds (VOC), although o^me monomers and other lower
molecular weight organlca may volatilize.
He pending ou the product requirements and the material being coated, a
surface may have one or more layers oT coating applied. The first coat may be
applied to cover surface imperfections or to assure adhesion of the coating.
The intermediate coats usually provide the required color, texture or prim,
and a cle&r protective topcoat is often added. General coating types do not
differ fro-a those described, although the intended use and the material to be
coeted deLermlne the composition and resins used In the coatings.
Coating Application Procedures - Conventional s,;ray, which Is air atomized
and usually hand operated, is one of the most versatile coating methods. Colors
can b-» changed easily, and a variety of sl^es and shapes can be painted under
4/81 Evaporation Loss Sources 4.2.2.1-1
-------
many operating conditions. Conventional, catalyzed or waterborne coatings can
be applied with little modification. The disadvantages are lov efficiency from
overapray and high energy requirements for the air compressor.
In hot airless spray, the paint Is forced through an atomizing nozzle.
Since volumetric flow Is less, overapray Is reduced. Less solvent Is also
required, thus reducing VOC emissions* Care must be taken for proper flow of
the coating, to avoid plugging and abrading of the rozzle orifice. Electro-
static epray Is most efficient for low vJaoclty paints. Charged paint par-
tlciea are attracted to an oppositely charged surface. Spray guns, spinning
dlscu or bell shaped atomizers can be uaed to atomize the paint. Application
efficiencies cf 90 to 93 percenr ai'e possible, with good "wraparound" and edge
coating. Interiors and renessed surfaces Are difficult to coat, however.
Roller coating is used to apply costings and Inks to flat sirfacee. If
the cylindrical rollers move li: the same direction as the surface to be coated,
the system Is called a direct roll coater. If they rotate 1n the opposite
direction, the system Is a reverse roll coater. Coatings can be applied to any
flat surface efficiently and uniformly and at high speeds. Printing and deco-
rative graining are applied with direct rollers. Reverse rollers are used to
apply fillers to porous or imperfect substrates, including papers and fabrics,
to give a smooth uniform surface.
Knife coating Is relatively inexpensive, but It is not appropriate for
coating unstable materials, such an eome knit goods, or when a high degree of
accuracy In the coating thickness Is required.
Rotogrcvure printing is widely used In coating vinyl imitation leathers
and wallpaper, and in the application or a transparent protective layer over
the printed pattern. Tn rotogravure printing, the image area is recessed, or
"intaglio", relative to the copper plated cylinder on which the Image is
engraved. The Ink is picked up on the engraved area, and excess ink Is scraped
off the nonImage area with a "doctor blade". The Image is transferred directly
to the paper or other substrate, which lj web fed, and the product Is then
dried.
Dip coating require; that the surface or the subjprt he i miner ted in a bath
of paint. Dipping Is effective for coating Irregularly shaped or bulky items
and for priming. All surfaces are covered, but coating thickness varies, edge
blistering can occur, and ;> good appearance la not always achieved.
In flow coating, mateilals to b.2 coated are conveyed through a flow of
paint. P-int flew It, directed, without atomizatlun, toward the eurfe:e through
orjltlple nozzles, then is caught in a trough and recycled. For flat surfaces,
close control of film thickness can be maintained by passing the surface
through a constantly flowing curtain of paint ar a controlled rate.
Emissions and Control* - Essentially all of the VOC emitted from the sur-
face coating Industry is from the solvents which are used in the p*int formu-
lations, used to thin paints at the coating facility or used for cleanup. All
unrecovere.d solvent can be considered potential emissions. Monomers and low
molecular weight organlcs can bo emlttei! from those coatings that do not Include
solvents, but such em^af-one are essentially negligible.
4.2,2.1-2 EMISSION FACTORS 4/P1
-------
Emissions fron surface coating for an uncontrolled facility can be esti-
mated by assuming that all VOC In the coatings la emitted. Usually, coating
consinptlon volume will be known, and some Information about the types of
coatings and solvents will be available. The choice of a particular emission
factor will depend on the coating data available. If no specific Information
Is given for the coating, It may be estimated from the data In Table 4.2.2.1-2.
TABLE A.2.2.1-1. VOC EMISSION FACTORS FOR UNCONTROLLED SURFACE COATING*
EMISSION FACTOR RATING: 3
Available information on coating
Emissions o* VOCb
kg/liter of coating ' Ib/gal of coating
Conventional or water bo me
paints
VOC, wt % (d)
VOC, vol % (V)
Waterborne paint
VOC as weight Z of total
volatilee - including water
(X); total volatlles as
weight Z of coating (d)
VOC ae volume Z of total
volatlles - Including water
(Y^; total volatlles as
volume Z of coating (V)
d*coating density0
d'coating density0
100
V'0.8Bd
100
d'X'coating density6
100
V7.36*
100
d'X'cooti'ng density0
100
V«Y'0.88d
100
101
V'Y-7.36d
100
aNaterlal balance, when coatings volume use is known.
kpor special purposes, factors expressed kg/1 of coating less water may be
desired. These may be computed as follows:
Factor as kg/1 of coating
- Factor as kg/1 ot coating less water i _ volume % water
100
clf roe ting density Is not known, it can be estimated from the Information
in Table 4.2.2.1-2.
dihe values 0.88 (kg/1) and 7.36 (Ib/gal) use the average density of
solvent in coatings. Use the densities of the solvents in the coalings
actually uatd by the source, if known.
4/81
Evaporation Loss Source
4.2.2.1-3
-------
TA3LE 4.2.2.1-2. TYPICAL DENSITIES AND SOLIDS CONTENTS OF COATINGS
Type of coating
Enamel , air dry
Enanel, baking
Acrylic enamel
Alkyd ev. ;uci
Primer surfacer
Primer, epoxy
Varnish, baking
Lacquer, spraying
Vinyl, roller coat
Polyurethane
Stain
Sealer
Magnet wire enamel
Paper coating
Fabric coating
Density
kg/liter
0.91
1.09
1.07
0.96
1 =13
1.26
0.79
0.95
0.92
1,10
0.86
0.84
0.94
0.92
0.92
Ib/gal
7.6
9.1
8.9
8,0
9.4
10.5
6.6
7.9
7.7
9.?.
7.3
7.0
7.8
7.7
7.7
Solids
(volume Z)
19.6
42.8
30.3
47.2
49.0
57.2
35.3
26.1
12.0
31.7
21.6
11.7
25.0
22.0
"2.0
Reference 1 .
All solvents separately purchased as solvent that are used in surface
coating operations and are not recovered subsequently can be considered
potential emissions. Such VOC emissions at a facility can result from onalte
dilution of coatings with solvent, from "makeup solvents" required In flow
coating and, in some instances, dip coating, and from the solvents used for
cleanup. Makeup solvents are added to coatings to compensate for standing
losses, concentration or amount, and thus to bring the coating back to working
specifications. Solvent emissions should be added to VOC emissions from
coatings to get total emissions from a coating facility.
Typical ranges of control efficiencies are given in Table 4.2.2.1-3.
Emission controls normally fall under one of three categories - modification in
paint formula, process changes, or addon controls. These are discussed further
in the specific subsections which follow.
TABLE 4.2.2.1-3. CONTROL EFFICIENCIES FOR
SURFACE COATINC OPERATIONS*
Control option
Substitute waterborne coatings
Substitute low solvent coatings
Substitute powder coatings
Add afterburners/Incinerators
Reductlonb
(*>
60-95
40-80
92-98
95
aRefurences 2-4.
^Expressed as X of total uncontrolled emission load.
4.2.2.1-4
EMISSION FACTORS
4/81
-------
Raf«r«nc«a for Section 4.2.2.1
1. Controlling Pollution froa the Manufacturing and Coating of Metal
Product!; Metal Coating Air Pollution Control, EVA-6 25/3-77-009, U. S.
Environmental Pr. fctlon Agency, Cincinnati, OH, May 1977.
2. H. R. Powers, 'Economic ->nd Energy Savings through Coating Selection",
The Sherwin-Williams Company, Chicago, TL. February 8, 1978.
3. Air Pollution Engineering Manual, Second Edition, AP-40, U. S.
Environmental Protection Agency, Research Triangle Park, NC, May 1973.
Out of Print.
4. Products Finishing. 4_l(6A):4-54, March 1977.
4/81 Evaporation Loss Sources 4.2.2.1-')
-------
A.2.2.2 CAN COATING1~A
Process Description - CADI may be made from a rectangular rlieat (body blank)
and two circular ends (three piece cans), or they can be drawn and wall Ironed
from a ihallow cup to which an end la attached after the can is filled (two
piece cans). There are major differences In coating practices, depending on
the type of can and the product packaged in it. Figure 4.2.2.2-1 depicts a
three piece can sheet printing operation!
There are bo'': "toll" and "captive" can coating operations. The former
fill orders to customer specifications, and the latter coat the metal for pro-
ducts fabricated within one facility. Some can coating operations do both
toll and r.a^tlve work, and some planM fabricate just can ends.
Three piece can manufacturing Involves sheet coating and can fabricating.
Sheet coating Includes base coating aid printing or lithographing, followed by
curing at temperatures of up to 220°C (425°F). When the sheets have been
formed Into cylinders, the seaa is sprayed, usually with a lacquer, to protect
the exposed metal. If they are to contain an edible product, the interiors are
epray coated, and the cans baked up Co 220°C (4?5°F).
Two piece cans are used largely by beer and other beverage Industries*
The exteriors may be reverse roll coated in white and cured ac 170 to 200°C
(325 to 400°F). Several colors of Ink are then transferred (sometimes by
lithographic printing) to the cans as they rotate on a mandrel. A protective
varnish may be roll coated over the inks. The coating Is then cured la a
single or multipass oven at temperatures of 180 to 200QC (350 to 400*7). The
cans are spray coated on the Interior and spray and/or roll coated on the
exterior of the bottom end. A final baking at 110 to 200°C (225 to 400*7)
completes the process.
Emissions and Controls - Emissions from can coating operations depend on
composition of the coating, coated area, thickness of coat aitl efficiency of
application. Post-application chemical changes, and nonrolvent contaminants
like oven fuel combustion products, may also affect the composition of emis-
sions. All solvent used and not recovered can be considered potential
emissions.
Sources of can coatJng VOC emissions include the coating area and the oven
area of the sheet base rnd lithographic coating lines, the three piece can side
seam and interior spray coating processes, and the two piece can coating and
end sealing compound lines. Emission rates vary with line speed, can or sheet
size, and coating type. On sheet coating lines, where the coating Is applied
by rollers, most solvent evaporates In the oven. For other coating processes,
the coating operation Itself Is the major source. Emissions can be eetlmated
from the amount of coating applied by using the factors In Table 4.2.2.1-1 or,
If the number and general nature of the coating lines are known, from Table
4.2.2.2-1.
Incineration and the use of vaterborne and low nolvent coatings both
reduce organic vapor emissions. Other technically feasible control options,
such as electrostatically r>prayed powder coatings, are not presently applicable
to the whole Industry. Catalytic and thermal Incinerators both car. be used,
Eviooratioii Loss Sources 4.2.2.2-1
-------
ro
ro
(•O
HINArPtlCArORS
O
JD
PRESSURE
LITHOGRAPH ROLLERS OVER VMMSH
COATER COATER
WCUTOVEH
SHIETIPlAfll
FEEDER
SHEET (PUH)
STACKER
Figure 4.2 2.2-1. Three piece can sheet printing operation
oo
-------
TABLE 4.2.2.2-1. VDC EMISSION FACTORS FOR CAN COATING PROCESSES8
EMISSION FACTOR RATING: B
Process
4
Three piece can &neet base coating line
Three piece can sheet lithographic
coating line
"•"hree piece beer and beverage can - aide
seam spray coafl/ig process
Three piece beer and beverage can -
.Interior body spray coating process
Two piece can coating 15 ne
Two piece can end sealing compound line
Typical ealislons
from coating llneb
Ib/hr
112
65
12
54
86
8
kg/hr
51
30
5
25
39
4
Est<»eted
fraction
from coater
area (Z)
9-12
8-11
100
75-85
NA
100
Estimated
fraction
from oven
<*>
88-91
89-92
air dried
15-25
NA
air dried
Typical organic
evictions0
Hg/yr
160
50
18
80
260
14
toa/yr
176
55
20
86
287
15
6.
-a
o
o
3
r-
o
CD
CO
CO
o
H
O
n
.r-
•
ro
IsJ
aR ferinee 3. NA ° not available.
''Organic solvent emlpaiuns will vary according to line speed , size of can or sheet being coated, and
type of coating useJ.
cBased upcn normal operating conditions.
-------
TABLE 4.2.2.2-2. CONTROL EFFICIENCIES FOR CAN COATING LINES8
Affected facility**
Control option
Reduction0
(X)
Two Piece Can Line*
Exterior coating
Interior spray
coating
Three Piece Can Line a
Sheet coating llnea
Exterior coating
Interior spray
coating
Can fabricating llnea
Sid'! aeam spray
coating
Interior spray
coating
End Coating Llnea
Sealing compound
Sheet coating
Thermal and catalytic Incineration
Waterboroe and high solids coating
Ultraviolet curing
Thermal and catalytic Incineration
Waterborne and high solids coating
Powder coating
Carbon adsorption
Thermal and catalytic Incineration
Watarborue and high solId a coating
Ultraviolet curing
Thermal and catalytic Incineration
Waterborne and high solid a coating
Waterborne and high solida coating
Powder (only for uncemented seams)
Thermal and catalytic Incineration
Waterborne and high solids coating
Powder (only for uncemented seams"/
Carbon adsorption
Waterborne and high solids coating
Carbon adsorption
Thermal and catalytic Incineration
Waterborne and high soluis costing
90
60-90
<100
90
60-90
100
90
90
60-90
£100
90
60-90
60-90
100
90
60-90
100
90
70-95
90
90
60-90
aReference 3.
DColl coating lines consist of coaters, ovens and quench areas. Sheet, can
and end wire coating lines consist of coaters and ovens.
^Compared to conventional solvent base coatings used without any added
4.2.2.2-4
EMISSION FACTORS
4/81
-------
prlaers, backers (coatings on the reverse or bucksIde of the coll), and some
vaterborne low to medium gloss topcoats have been developed that equal the
performance of organic solventborne coatings for aluminum but have not yet been
applied at full line speed In all cases. Waterborne coatings for other metals
are being developed•
Available control technology Includes the use of addon devices like
Incinerators and carbon adsorbers and a conversion to low solvent and ultra-
violet curable coatings* Thermal and catalytic incinerators both may be ^sed
to control emissions froa three piece can sheet bese coating lines, sheet
lithographic coating lines, and Interior spray coating. Incineration Is appli-
cable to two piece can coating lines- Carbon adsorption la moat acceptable to
low temperature processes which use a limited number of solvents. Such pro-
cesses Include two and three piece can Interior spray coating, two piece can
end sealing compound lines, and three piece can side seam spray coating.
Low solvent coatings are not yet available to replace all the organic
aolventborne formulations presently used in the can Industry. Waterborne
baaecoata have been succecsfully applied to two piece cans. Powder coating
technology is used for side seam coating of nonceoeiued three piece cans.
Ultraviolet curing technology is available for rapid drying of the first
two colors of ink on three piece can sheet lithographic coating lines.
References for Section 4.2.2.2
1. T. W. Hughes, et al., Source Assessment: Pr.'orltiiatlon of Air Pollution
from Industrial Surfac«~Coating Operations, EPA-650/2-75-019a, U. S.
Environmental Protection Agency, Research Triangle Park, NC, November 1075,
2. Control of Volatile Organic Emissions froa Existing Stationary Sourcep.
Volume I: Control Methods for Surface Coating Operations, EPA-450/2-7b-
028, U. S. Environmental Protection Agency. Research Triangle Park, NC,
May 1977.
3. Control of Volatile Organic Emissions from.Existing Stationary Sources,
Volume II: Surface Coating of Cans, Colls, Paper Fabrics, Au-omobiles,
andLight Duty Trucks, EPA-450/2-77-008, U. S. Environmental Protection
Agency, Research Triangle Park, NC, May 1977.
i
4. Air PollutionControl Technology Applicable to 26_Source of Volatile
Organic Compounds, Office of Air Quality Planning and Standards, U. S.
Environmental Protection Agency, Research Triangle Park, NC, Hay 27, 1977.
Unpublished.
4/81 Evaporation Loss Sources 4..?.2. 2-5
-------
4.2.2.3 MAGNET WIRE COATING1
Process Description - Magnet wire coating is applying a coat of electrically
insulating varnieh or enamel to aluminum or copper vire used in alectrical
machinery. The wire la uaually coated in large plants that both draw and
Insulate It and then sell It to electrical equipment manufacturers. The wire
coating must meet rigid electrical, themal and abrasion specifications.
Figure 4.2.2.3-1 shows a typical wire coating operation. The wire is
unwound from spools and passed through an annealing furnace. Annealing softens
the wire and cleans it by burning off oil and dirt. Usually, the wire ';hen
paaaea through a bath in the coating applicator and is drawn through an orifice
or coating die to scrape off the excess. It is then dried and cured l'i a two
zone oven first at 200*, then 430°C (400 and 806°P). Wire nay pass through the
coating applicator and the oven as many as twelve tines to acquire th>i necessary
thickness of coating.
Emissions and Controls - Emissions from wire coating operationa depend on
composition of tha coating, thickness of coat and efficiency of application.
Postappllcation chemical changes, and nonaolvent contaminants such as ovan fuel
combustion products, may also affect the compoaltlon of emissions. All solvent
used and not recovered can be considered potential emissions.
The exhaust from the oven Is the most Important aource of solvent emissions
in the wire coating plant* Enisaiona from the applicator are comparatively low,
because a dip coating technique is uaed. Sea Figure 4.2.2.3-1.
Volatile organic compound (VOC) emissions may be estimated from the factors
in Table 4.2.2.1-1, if the coating usage is known and if the coater has no
controls. Host wire coaters built since 1960 do have controls, so the Infor-
mation In the following paragraph nay be applicable. Table 4.2.2.3-1 gives
estimated emissions for a typical wire coating line.
TABLE 4.2.2.3-1
ORGANIC SOLVENT EMISSIONS FROM A TYPICAL WIRE
COATING LINE*
Coating
kg/hr
12
Llneb
Ib/hr
26
Annual
Mg/yr
84
lc.talac
ton/yr
93
BReference
^Organic solvent emissions vary from I lie to line by size and
speed of vire, number of vires per ov<-n, and number of passes
through oven. A typical line may coat 544 kg (1,200 Ib) wire/day.
A plant may hav« many lines.
cBased upon normal operating conditions of 7,000 hr/yr for one 11 l
without incinetatot.
4/81
Evaporation LOSJ Sources
4.2.2.3-1
-------
i
§
1
a
ra
O
u
CO
o
o>
'*• ..—.— ..-..— .. ^ . I. v^.
^_A_ - - -1^7"
u
i
4.2.2.3-2
EMISSION FACTORS
4/81
-------
Incineration la the only commonly used technique to control emissions from
wire coating operations. Since about I960, all major wive coating designers
have incorporated catalytic incinerators into their oven designs, because of
the economic benefits. The interns! catalytic incinerator burns aolvent fives
and circulates heat back into the wire drying zone. Fuel otherwise needed to
operate the oven la eliminated ur greatly reduced, as are costs* Essentially
all solvent emissions from the oven can b« directed to an Incinerator with a
combustion efficiency of a least 90 percent.
Ultraviolet cured coatings are available for special syateus. Carbon
adsorption la not practical. Use of low solvent coatings id only a potential
control, because they have not yet been developed with properties that meet
Industry's requirements.
References for Section 4.2.2.3
I. Control of Volatile Organic Emissiona from Existing Stationary Sources.
Volume IV; Surface Coatinglor Insulation of Magnet Wire. EPA-450/2-77-
033, U. S. Environmental Protection Agency, Research Triangle Park., NC,
December 1977.
2. Conerolledand Uncontrolled Emission Rates and Applicable Limitations for
Eighty Processes, EPA Contract Number 68-02-1382, TRC of New England,
Werhersfleld, CT, September 1976.
4/81 Evaporation Loss Sources 4.2.2.3-3
-------
4.2.2.4 OTHER METAL COATING1"3
Process Description - Lar^e appliance, metal furniture and nlscellaneous metal
part and product coating llnea have many common operations, similar emission*)
and emission points, and available control technology. Figure 4.2.2.4-1 shows
a typical metal furnlti.-e coating tine.
Large appliances Include doors, cases, lids, panels and interior support
parts of washers, dryers, ranges, refrigerators, freezers, water heaters, air
conditioners, and associated products. Metal furniture Include* both outdoor
and Indoor pieces manufactured for household, business or Institutional r.se.
"Miscellaneous parts and products" herein denotes large and small farm machin-
ery, small appliances, Commercial and Industrial machinery, fabricated iiet«l
products and other Industries that coat metal under Standard Industrial
Classification (SIC) codes 33 through 39.
Large Appliances - The coatings applied to large appliances are usually
epoxy, epoxy/acryllc or polyester enamels for the primer or single coat, and
acrylic en ante la for the topc^et Coatings containing alkyd resins are also
used. Prime and Interior single coats are applied at 25 to 36 volume percent
solids. Topcoats and exterior single coats are applied at 30 to 40 volume
percent. Lacquers may be used to touch up any scratches that occur during
assembly. Coatings contain 2 to 15 solvents, typical of which are eaters,
ketones, apllphatlcs, alcohols, aromatlcs, ethers and trrpenes.
il parta are generally dip coated, and flaw or spray coating is used
for larger partis. Dip and flcrf coating are performed in an enclosed room
vented either by a roof fan or by an exhaust system adjoining the drain board
or tunnel. Down or side draft booths remove ovarepray and organic vapcrs from
prime coat spraying. Spray booths are also equipped with dry filters or a
water wash to trap overspray.
Farts may be touched up manually with conventional or airless spray equip-
ment. Then they are tent to a flaahoff area (either open or tunneled) for
about 7 minuces .-.nd are baked In a wultipac.3 oven for about 20 minutes at 180
to 230eU (350 to 450°F). At that point, large appliance exterior parts go on
to the topcoat application area, and single coated interior parts are moved to
the assembly area of the plait.
The topcoat, and some time a primers, are applied by automated electrostatic
disc, bell or other typeo of spray equipment. Topcoats often are more than one
color, changed by automatically flushing out the system with solvent. Both the
topcoat and touchup spray areas are designed with side or down draft exhaust
control. The parts go through about a 10 minute flaat.jff period, followed by
baking in a multipass oven for 20 co 30 minutes at 140 to 180'C (279 to 350°F).
Metal Furniture - Most metal furniture coatings are enameln, although some
lacquers are used. The uiost common coatings are alkyd a, epoxles and acrylics,
;hich contain the same solvents used In large appliance coatings, applied at
about 25 to 35 percent foMds.
On a typical metal furniture coating line (sec Figure 4.2.2.4-1), the
prime coat can be applied with tfrv oame methods used for large appliances, but
it may be cured at slightly lower temperatures, 150 to 200*C (300 To 400°F) .
4/81 Evaporation Loss Sources 4.2.2.4-1
-------
)
itk
ro
ITI
in
V}
o
30
V)
CLfAHHG
AMD
MFPAMTION
CDHVIHTMIUL
M IUCTKWMT1C.
AMOTMH.ESS.
SPMVCMTHK
COATIMB
(OPT10ML - USED
OHIVII1WOCMT
UPEMTIDM)
ASSEIMLV
now
TOP CWTIHC
OH SINGLf COAT
OPERATION
oc
Figure 42 2 41 Metal product coating line emission points
, 11
-------
Th* topcoat, usually Lh« only coat, la applied vlth electrostatic spray or vlth
conventional airless or air spray. Most spray coating Is manual, In contrast
to large appliance operations. Flow coating or dip coating Is done, If the
plant generally uses only one or two colors on a line.
the coated furniture la usually bakeJ, but in some cases it is air dried.
If It Is to be baked, it passes through a fleshoff area Into a multizone ovan
at temperatures ranging from 150 to 230°C (300 to 450°F).
Miscellaneous Ketdl Parts and Products - Both enamels (30 to 40 volume
percent solids) and lacquers (10 to 20 volume percent solids) are used 11 coat
miscellaneous metal parts and products, although enamels are more common.
Coatings often are purchased at higher volume percent solids but are thlr.ned
before application (frequently with aromatic solvent blends). Alkyds are
popular with induatrlal and faro machinery manufacturers. Most of the coatings
contain several (up to 10) different solvents, Including ketones, esters,
alcohols, allphatlcs, ethers, aromatlcs and terpenes.
Single or double coatings are applied in conveyored or batch operations.
Spraying la usually employed for single coats. Flow and dip coating may be
uaad when only one or two colors ara applied. Por two coat operations, primers
ara usually applied by flow or dip coating, and topcoats are almost always
appllad by spraying. Electrostatic spraying Is common. Spray booths and areas
ar*> kept at a alight negative pressure to capture overspray.
A manual two coat operation nay be used for large items like industrial
and farm machinery. The coatings on large products are often air dried rather
than oven baked, because tiie machinery, when completely assembled, incluleu
heat sensitive materials and may be too large to be cured in an oven. Miscel-
laneous parts and products can be baked In single or mrtltlpasa ovens fit 150 to
230'C (300 to 450eF).
Emissions and Controls - Volatile organic compounds (VOC) are emitted
from application atJ flashoff areas and the evens of metal coating lines. See
Figure 4.2.2.4-1. The composition of emissions varies among coating lines
according to physical construction, coatlug method and type of coating applied,
hut distribution of emissions among individual operations has been assumed to
b« fairly constant, regardle--9 of the Lype of co-iii^ Tine or the specific pro-
duct coated, as Table 4.2.2.4-2 IndicnteH. All solvent used can be considered
potential emissions. Emissions can be calculated from the factors in Table
4.2.2.1-1 If coatings use la known, or from the factors In Table 4.2.2.4-2 if
only a general description of the plant IB available. For emissions from the
cleansing and pretreatment area, see Section 4.6, Solvent Degreasing.
When powder coatings, which contain almost no VOC, are applied to uome
metal products as a coatlrg mollification, eiaisnlcna are greatly reduced.
Powder coatings are applied as single coats on gome large appliance inferior
parts and as topcoat for kitchen ranges. They are also used on metal bed and
chair frames, shelving and stadium seating, and they have been applied as
single coats on small appliances, small fam machinery, fabricated metal pro-
duct pai'ts and industrial machinery components. The usual application methods
are manual ot ^"t-omatlc electrostatic apray.
4/81 Evaporation Loaa Sources 4.2.2.4-3
-------
to
ISJ
TABLE 4.2.2.4-1. ESTIMATED CONTROL TECHNOLOGY EFFICIENCIES FOR METAL COATING LINES*
o
z
n
3
;*.
Critrol
Technology
Powder
Water born* (iprny,
dip, fiowcoat)
Hacerborne (elee-
ti ixlepoiltloa)
Higher solids
(•pray)
Carbon absorption
Incineration
Application
Large appliance*
Top, exterior or
Intei lor • ingle
coat
AJ1 application*
Prl«e or Interior
•ingle coat
Top or exterior
• Ingle coat and
aound deadener
Prl
60-80b
90<*
90d
(fetal
furniture
95-99D
6O-90b
90-95*
50-SOb
90*
90
-------
.p-
OD
TABLE 4.2.2.4-2. EMISSION FACTORS FOR TYPICAL METAL COATING PLANTS*
EMISSION FACTOR RATINC: B
0)
T3
O
"I
Oi
O
3
f
O
00
CD
in
D
C
1
r>
n>
ID
Type of Plant
Lar^'' appliances
Print and topcoat spray
Metal iuiDlturF.b
Slnijle iprayc
Single dlpd
Miscellaneous BetalD
Conveyor ologle flow1'
Conveyor dip
Conveyor • Ingle gpraye
Conveyor two coat, flow and
spray
Conveyor two coat,
E (Mg/yr)
where V - VOC at »ol
cTranifer efficiency aaaiaed to be 601, prcaiatlag the eoater uaea aianiial electrcatatic
JFlou and dip coat tranafer ef f iclenciea aaauoed to be 90Z.
'Transfer efficiency aasuoed to be 501, pressing the eoater uaei electroatatlc
wide rang! of product altet and caof Iguration*.
but coitt a
I
Ul
-------
Improving transfer efficiency Is a method of reducing emissions* One
such technique la the electrostatic application of the coating, and another
is dip coating with vaterborne paint. For example, many makers of large
appllanceo are now using electrodeposltion to apply prim a coats to exte> i.or
parts and single coats to Interiors, because this technique Increases corrosion
protection and resistance to detergents. Electrodeposltion of these waterborne
coatings Is also being u&ed at several metal furniture coating plants and at
some farm, commercial machinery and fabricate! metal products facilities*
Automated electrostatic spraying Is nost efficient, but manual and
conventional methods can be used, also. Roll coating Is another option on some
miscellaneous parts. Use of higher solids coatings la a practiced technique
for reduction of VOC emissions.
Carbon adsorption la technically feasible for collecting emissions from
prime, top and single coat applications and flarhoff areas. However, the
entrained sticky paint particles are a filtration problem, and adsorbers are
noc commonly used.
Incineration Is used to reduce organic vapor emissions from baking ovens
for large appliances, metal furniture and miscellaneous products, and it la an
option for control of emissions from application and flashoff areas.
Table 4.2.2.4-1 gives estimated control efficiencies for large appliance,
metal furniture and miscellaneous metal part and product coating lines, and
Table 4.2.2.4-2 giv.jg tho.ir emission factors.
References for Section 4.2.2.4
1. Controlof Volatile Orka-iic Emissions from Existing Stationary Sources,
Volume III; Surface Coating of Metal Furniture, EPA-450/2-77-032, U. S.
Environmental Protection Agency, Research Triangle Park, NC, December 1977.
2. Control of Vol
-------
4.2.2.5 FLAT WOOD INTERIOR PANEL COATING
Process Description1 - Finished flat wood construction products are Interior
panels made of hardwood plywoods (natural and lauan), particle board, and
hard board .
Fewer than 25 percent of the manufacturers of such flat wood products
coat the products In their plants, and In some of the plants that do coat, only
a small percentage of total production Is coated. At present, most coating Is
done by toll coaters who receive panels from manufacturers and undercoat or
finish then according to customer specifications and product requirements.
Some of the layers and coatings that can be factory applied to flat woods
are filler, sealer, groove coat, primer, stain, basecoat, Ink, and topcoat.
Solvents used In organic base flat wood coatings are usually component mix-
tures, including methyl ethyl ketone, methyl Isobutyl ketone, toluene, xyle.ie ,
butyl acetates, propanol, ethanol, butanol, naphtha, methanol, amyl acetate,
mineral spirits, SoCal I and II, glycolo, and glycol ethers. Those most often
used In waterborne coatings are glycol, glycol ethers, propanol and butanol.
Various forms of roll coating are the preferred techniques for applying
coatings to flat woods. Coatings used for surface cover can be applied with
a direct roller coster. and reverse roll eoaters are generally used to apply
fillers, forcing the filler Into panel cracks and voids. Precision coating
and printing (usually with orfset gravure grain printers) are also forms of
roll coating, and several types of curtain coating may be employed, also
(usually for topcoat application). Various spray techniques and brush coating
may be used , too .
Interior paneling? are produced from plywoods with hardwood
surfaces (primarily lauan) and from various wood composition panels, Including
hard board and particle board, finishing techniques are used to cover the
original surface and to produce various decorative effects. Figure 4.2.2.5-1
Is a flow Diagram showing some, but not all, typical production line variations
for printed Interior panel in™.
Groove coatings, applied In different ways and at different points In the
coatlrg procedure, are usually plgmented low resin solids reduced with water
before use, therefore yielding few, if any, emissions. Fillers, usually applied
by reverse roll coating, may be of various formulations: (1) polyester (which
is ultraviolet cured), (2) water base, (3) lacquer base, (4) polyur ethane and
(5) alkyd urea base. Water base fillers are in common use on printed pant ling
lines .
Sealers may be of water or aolvtit base, usually applied by airless sprtsy
or direct roll coating, respectively. Basecoats , which tre usually direct roll
coated, generally ar? of lacquer, synthetic, vinyl, modified alkyd urea,
catalyzed vinyl, or water base-
Inks are applied by an offset gravure printing operation similar t>> direct
roll coating. Most lauan printing Inks are pigments dispersed In alkyd reslu,
with some nitrocellulose added for better wipe and prlntabiMty . Water base
4/81 Evaporation Loss Sources 4.2.2.5-1
-------
inks have a good future for clarity, cost and environmental reasons. After
printing, a boaro goes through one or two direct or precision roll cotters
for application of the clear protective topcoat. Sone topcoats ate synthetic,
prepared from solvent soluble alkyd or polyester reelns, urea formaldehyde
cross linlcings, resins, aud solvents.
Natural hardwood plywood pai.els are coated with transparent or clear
finishes to enl'unce and protect their face ply of hardwood veneer. Typical
production lines ara similar to those for printed interior paneling, except
tha.: a primer sealer is applied to the filled panel, usually by direct roll
coating. The panel is then embonsed and "valley printed" to ^ive a "dis-
tressed" or antique appearance. No basecoat is required. A sealer is also
applied t-fter printing but before application of the topcoat, which may be
curtain coated, although direct roll coating remains the usual technique.
Emissions and Controls*-^ - Emissions cf volatile organic compounds (VOC) at
flat wood coating plants occur primarily from reverse roll coating of filler,
direct roll coating of sealer and basecoat, printing of wood giain patterns,
direct roll or curtain coating of topcoat(s), and oven drying after one or
more of those operations (sea Figure 4.2.2.5-1). All solvent used and not
recovered can be considered potential emissions. Emissions can be calculated
from the factors In Table 4.2.2.1-1, if tha coating use is known. Emissions
for Interior printed panels can be estimated from the factors in Table
4.2.2.5-1, if the area of coated panels is known.
Waterborne coacings are Increasingly used to reduce emissions. They can
be applied to almost all flat wood except redwood and, possibly, cedar. The
major use of waterborne flat wood coatings is in the filler and basecoat
applied to printed interior paneling. Limited use has been made of waterborne
materials for Inks, groove coats, and topcoats with printed paneling, and for
inks and groove coats with natural hardwood panels.
Ultraviolet curing systems are applicable to clear or semi transparent
fillers, topcoats on particle board coating lines, and specialty coating oper-
ations. Polyester, acrylic, urethane and alkyd coatings can be cured by this
method.
Afterburners can be used to control VOC emissions from baking ovens, aneen demonstrated.
4.'<.2.5-2 EMISSION FACTORS 4/81
-------
CO
0)
T3
O
O
I/)
in
O
c
f BRJSH"|*fcHOUJv€l*rCJwT r
I _— 1 I . i. — -J *- — » „„„_„ nJ
NJ
in
LJ
Figure 4 22 5-1 FJat Wood interior panel coating line emission prints.^
MC - DIVERSE ROU COATlriC
OKC - OIBECT NOLL COAT1W,
-------
Ln
I
TABLE 4.2.2.5-1. VCC EMISSION FACTORS FOR INTERIOR PRINTED PANELS4
EMISSION FACTOR RATING: B
CO
in
h-i
O
•n
n
H
O
Paint
Category
Filler
Dealer
Basecoat
Ink
Topcoat
Coverage**
liter/lOOm2
Water
borne
6.5
1.4
2.6
0.4
2.6
Conven-
tional
6.9
1.2
3.2
0.4
2.8
gal/1,000 ft2
Water
borne
1.6
0.35
3.2
O.I
0.65
Conven-
tional
1.7
0.3
0.65
O.I
0.7
Uncontrolled VOC Emissions
kg/lOOa2 coated
Water
borne
0.3
0.2
0.8
0.1
0.4
Conven-
tional
3.0
0.5
0.2
0.3
1.3
Ultra-
violet0
Neg
0
0.24
0.10
Neg
lb/1,000 ft2 coated
Water
borne
0.6
0.4
0.5
0.2
0.8
Conven-
tional
6.1
l.l
5.0
0.6
3.7
Ultra-
violet
Neg
0
0.5
0.2
N*«
TOTAL 13.5 14.5 3.4 3.6 1.2 8.0 Q.<* 2.5 16.5 0.8
^Reference 1. Organlcs are all nonaethane. Neg • negligible.
Reference 3. From Abltlbl rorp., Cucaaonga, CA. Adjuataenta between water and conventional paints Bade
using typical nonvolatiles content.
CUV line uses no sealer, uses waterborne basecoat and ink. Total adjusted to cover potential emissions
from UV coatings.
00
-------
References for Section 4.2.2.5
1. Control of Volatile Organic Emissions from Existing Stationary Sources,
Volume VII; Factory Surface Coating of Flat Uood Interior Psnellnfil~EPA-
450/2-78-032, U. S. Environmental Protection Agency, Research Triangle
Park, NC, June 1978.
2. AirPollution Control TechnologyApplicable to26Sourceiof Volatile
Organic Compound•, Office of Air Quality Planning and Standard!, U. S.
Environmental Protection Agency, Research Triangle Park, NC, May 27, 1977.
Unpublished.
3. Products Finishing, 4li:6A):4-54, March 1977.
4/81 Evaporation LOSJ Sources A.2.2.5-5
-------
4.2.2.6 PAPER COATING
Process Description*""^ - Paper IB coated for various decorative and functional
purposes with watarborne, organic aolvantborna, or solvent free extruled mate-
rials. Paper coating Is not tj be confused with printing operations, which
use contraut coatings that must show a difference In brightness from the paper
to be visible. Coating operations are the application of a uniform layer or
coating acrobs a substrate. Printing results In au Image or design on the
substrate.
Waterborne coatings Improve prlntablllty and gloaa but cannot compete
with organic solventborne coatings In resistance to weather, scuff and chem-
icals. Solventborne coatings, as an added advantage, permit a wide range of
surface textures. Most solventborne coating Is done by paper converting com-
panies that buy paper from mills and apply coatings to produce a final product.
Among the many products that are coated with aolventborne materials are adhesive
tapee and labels, decorated paper, book covers, cine oxide coated office copier
paper, carbon paper, typewriter ribbons, and photographic film.
Organic solvent formulations generally iiard are made up of film forming
materials, plastlclzers, pigments and solvents. The main classes of film
formers used In paper coating are cellulose derivatives (usually nitrocellu-
lose) and vlnvl resins (usually the copolymer of vinyl chloride and vinyl
acetate). Three common plastlclzera are dloctyl phthalate, trlcresyl phos-
phate and castor oil. The major solvents used are toluene, xylene, methyl
ethyl ketone, isopropyl alcohol, methano1, acetone, and ethanol. Although a
single solvent is frequently used, a mixture Is often necessary to obtain the
optimum drying rate, flexibility, toughness and abrasion resistance.
A variety of low solvent coatings, with negligible emissions, hag been
developed for some uses to fovn organic realn films equal to those of con-
ventional solventborne coatings. They can be applied up to 1/8 inch thick
(usually by reverse roller coating) to products Uke artificial leather goods,
book covers and carbon paper. Smooth hot melt finishes can be applied over
rough textured paper by heated gravjre or roll coaters at temperacurea from 65
to 230°C (150 to 450aF).
Plaaclc extrusion coating is a type of hot meit coating in which a molten
thermoplastic sheet (usually low or medium density polyethylene) is extruded
from a slotted die at temperatures of up to 315°C (600°F). The substrate and
the molten plastic coat are united by pressure between a rubber roll and a
chill roll which solidifies the plastic. Many products, such as the polyeth-
ylene coated milk carton, are coated with solvent free extrusion coatings.
Figure 4.2.2.6-1 shows a typical paper coating line that uses organic
aolventborne femulations. The application device is usually a reverse roller,
a knife or a rotogravure printer. Knife coaters can apply solutions of much
higher viscosity than roll coaters can, thus emitting less solvent per pound of
solids applied. The gravure printer can print patterns or can coat a solid
sheet of color on a paper web.
4/81 Evaporation Loss Sources 4.2.2.6-1
-------
Ovens may be divided Into from two to five temperature zones. The first
zone is usally at about 43°C (110'F^, and other zones have progressively higher
temperatures to cure the coating after aost solvent has evaporated. The typi-
cal curing temperature is L20*C (250*F), and ovens are generally limited to
200°C (400*F) to avoid danape to the paper. Natural gas is the fuel uost often
used In direct fired ovens, but fuel oil is sometimes used. Some of the hea-
vier grades of fuel oil ir.an create problems, because SO and participate may
contaminate the paper coating. Distillate fuel oil usually can be used satis-
factorily. Steam produced from burning solvent retrieved iron an adsorber or
vented to an Indue re tor may also be used to heat curing ovens.
Emissions and Controls2 - The main emission points from payer coating lines are
the coating Applicator and th« oven (see Figure 4.2.2.6-1). In a typical paper
coating plant, about 70 perceil of all solvents used are emitted from the coat-
ing Hoes, with most coming from the first Tone of the oven. The other 30 per-
cent are emitted from solvent transfer, storage and mixing operations and can
be reduced through good housekeeping practices. All solvent used and not
recovered or destroyed can be considered potential emissions.
TABLE 4.2.2.6-1. CONTROL EFFICIENCIES FOR
PAPER COATING LINES*
Affected facility
Coating line
Control method
Incineration
Carbon adsorption
Low solvent coating
Efficiency (Z)
95
90+
80 - 99b
•Reference 2.
bBased on comparison with a conventional coating containing 35Z
solids and 65t organic solvent, by volume.
Volatile organic compounds (VOC) emissions from individual paper coating
plants vary with size and number of coating lines, line construction, coating
formulation, and substrate composition, so each oust be evaluated individually.
VOC emissions can be estimated from the factors in Table 4.2.2.1-1, if coating
use Is known arid sufficient information on coating composition is available.
Since many paper coating formulas are proprietary, It may be necessary to have
Information on the total solvent used and to assume that, unless a control
devize la used, esjentlally all solvent Is emitted. Rarely would aa much i\a 5
percent be retained in the product.
Almost all solvent emissions from the coating lines can be collected and
aent to a control device. Thermal incinerators have been retrofitted to a large
number of oven exhausts, with primary and even secondary heat recovery systems
heating the ovens. Carbon adsorption is aost easily adaptable to lines which
use single solvent coating. If solvent mixtures are collected by adsorbers,
they usually must be distilled for reuse.
Although available for some products, low solvent coatings are not yet
available for all paper coatirg operations. The nature of the products, auch
4.2.2.6-2
EMISSION FACTORS
4/81
-------
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O
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v
9)
01
n
o
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I
(Q
Q.
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(N
O)
^
3
u:
4/81
Evaporation LOBS Sources
4226-3
-------
as some typea of photographic film, may preclude development of a low solvent
option. Furthe more, the more complex the alxture of organic solvents In the
coating, the more difficult and expensive to reclaim them for reuse with a
carbon adsorption system.
References for Section A.2.2.6
1. T. W. Hughes, et__al., Source Assessment: Prioritlratlon of Air Pollution
from Industrial. Surface^ "Coating Ope rat long 7 EPA"650/2-75-019a. U. S.
Environmental Protection Agency, Research Triangle Park, NC, February 1975.
2. ControlofVolatile Organic Emissions from Existing Stationary Sources,
VolumeII;Surface Coating cf Cans, Colls, Paper Fabrics, Automobiles,
anr* Light Duty Trucks, Et'A-45072-77-008, U. S. Environmental Protection
Agency, Research Triangle Park, NC, May 1977.
4.2.2.6-4 EMISSION FACTORS 4/81
-------
4.2.2.7 FABRIC COATING1"3
Process Description - Fabric coating Imparts to a fabric substrate properties
such as strength, stability, water or acid repellence, cr appearance. Fabric
coating is the uniform application of an elastomcrlc or thermoplastic polymer
solution, or a vinyl plastisol or organoaol, across all of at least one aide
of a supporting fabric surface or substrate. Coatings * re applied by blade,
roll coater, reverse roll coater, and In some Instances, by rotogravure coater.
Fabric coating should not be confused with vinyl printing and top coating,
which occur almost exclusively on rotogravure equipment. Textile printing also
should not be considered a fabric coating process.
Produces usually fabric coated are rainwear, tents, tarpaulins, substrates
for Industrial and electrical tape, tire cord, seals, and gaskets. The industry
Is mostly small to medium size plants, many of which are toll coaters, rather
than specialists r« coating l
-------
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o
in
E
c
(0
0>
p
01
19
E
4 2.2 7-2
IM.'SblON FACTORS
4/81
-------
of incineration. As with other surface coating operations, carbon adsorption
li; mrst easily accomplished by sources using a single solvent that can be
recovered for reuse. Mixed solvent recovery la, however, in use la other web
coating processes. Fugitive emissions controls include tight covers for open
tanks, collection hoods for cleanup areas, and closed containers for storage
of solvent wiping cloths. Where high solids or waterborno coatings have been
developed to replace conventional coatings, their use may preclude, the need for
A control device.
References for Section 4.2.2.7
1. Control of Volatile Organic Emissions from Existing Stationary Sources,
Volume II: Surface Coatingof Cans, Coils, Paper Fabrics, Automobiles.
and Light Duty Tracks, EPA-450/2-77-008,U. S. Environmental Protection
Agency, Research Triangle Park, NC, May 1977.
2. B. H. Carpenter and G. K. Milliard, Environmental Aspects of Ch-fetalcal Uae
In Pr1n 11ng 0 pt ra 11on a, EFA-560/1-75-005, U. S. Environmental Protection
Agency, Washington, DC, January 1976.
3. J. C. Berry, "Fabric Printing Definition", Memorandum, Office of Air Quality
Planning and Standards, U. S. Environaental Protection Agency, Research
A!angle Park, NC, August 25, 1980.
4/81 Evaporation Lota Sources 4.2.2.7-0
-------
_
4.2.2.8 AUTOMOBILE AND LIGHT DUTY TRUCK SURFACE COATING OPERATIONS
General - Surface coating of an automobile body is a multlstep operation
carried out on an assembly line conveyor system. Such a line operates at a
need of 3 to 8 meters (9 to 25 feet) per minute and usually produces 30 to
70 units per hour. An assembly plant may operate up to two 8 hour production
shifts per day, with a third shift used for cleanup and maintenance. Plants
may stop production for a vacation of one and a half weeks at Christmas
through New Year's Day and may stop for several weeks in Summer for model
changeover.
Although finishing processes vary from plant to plant, they have some
common characteristics. Major steps of such processes are:
Solvert wipe
Phosphating treatment
Application of prime coat
Curing of prime coat
Application of guide coat
Curing of guide coat
Application of topcoac(s)
Curing of topcoat(s)
Final repair operations
A general diagram of these consecutive steps Is presented In Figure
A.2.2.8-1. Application of a coating takes place in a clp tank or spray
". -oth, and curing occurs in the flashoff area and bake oven. The typical
structures for application and curing are contiguous, to prevent exposure
of the wet body to the ambient environment before the coating is cured.
The automobile body Is assembled from a number of welded metal sections.
The body and the parts to be coated all pass through the same metal
preparation process.
First, surfaces are wiped with solvent to eliminate traces of oil and
grease. Second, a phosphatlng process prepares surfaces for the primer
application. Since iron and steel rust readily, phosphate treatment is nec-
essary to retard such. Phosphating also improves the adhesion of the primer
and the metal. The phosphating process occurs in a multistage washer, with
detergent cleaning, rinsing, and coating of the metal surface with zinc
phosphate. The narts and bodies pass through a water spray cooling process.
If solventborne primer is to be applied, they are then oven dried.
A primer is applied to protect the metal surface from corrosion a:id
to asu-jre stood adhesion of subsequent coatings. Approximate"y half of all
assembly plants use solventborne primers with a combination of manual and
automatic spray application. The rest use waterborne primers. As new plants
are constructed and exiting plants modernized, the use of waterborne primers
is expected to increase.
The term "soivsnt" here means organic solvent.
8/82
Evaporation Loss Sources
4.2.2.8-1
-------
*-
•
ro
•
ls»
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W
s
VI
w
M
i
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00
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ro
Body welded, \
.solder applied \
and ground /
f Sealants applied
Solvent
(kerosene)
wipe
Prime coat
(and sealant)
cured
A
Prime coat
applied (spray
or dip)
Prime coat
sanded
(
Topco.'t
sprayed*
A
Topcoat cured
ed -
A
'Second topcoat and]
touchup sprayed
I
Paint repair
cured or
dried
7 Btage
phosphating
IWater spray
| cooling j
Guide coat
sprayed
I
A
Guide coat
cured
, A,
Second topcoat
cured ;
'Potential
emission
iprints
<:Tc get sufficient film build, for two colors or a base coat/clear coat,
there may be multiple topcoats.
Figure 4.2.2.8-1. Typical automobile and light duty truck surface coating line.
-------
Waterborne primer Is moat often applied In an electrodeposition (EDP)
bath. The composition of the bath is about 5 to 15 volume percent solids,
2 to 10 percent solvent and the rest water. The solvents used an typically
organic compounds of higher molecular weight and low volatility, like
ethylene glycol monobutyl ether.
When EDP is used, a guide coat (also called a primer surfacer) is
applied between the primer and the topcoat to build Him thickness, to fill
in surface imperfections an^ to permit sanding betve.cn the primer and top-
coat. Guide coats are applied by a combination of manual and automatic
spraying and can be solventborne or waterbome. Powder guide coat is used
at one light duty truck plant.
The topcoat provides the variety of colors and surface appearance to
meet customer demand. Topcoata are applied in one to three steps to assure
sufficient coating thickness. An oven bake may fallow each topcoat appli-
cation, or the coating may be applied wet on wet. At a minimum, the final
topcoat is baked in a high temperature oven.
Topcoats in the automobile Industry traditionally have been solventborne
lacquers and enamels. Recent trends have been to higher solids content.
Powder topcoats have been tested at several plants.
The current trend In the industry is toward base coat/clear coat
(BC/CC) topcoating systems, consisting of a relatively thin application of
highly pigroented metallic base coat followed by a thicker clear coat. These
BC/CC topcoats have more appealing appearance than do single coat metallic
topcoats, and competitive pressures are expected to increase their use by
U. S. manufacturers.
The VOC content of most BC/CC coatings in use today is higher than that
of conventional enamel topcoats. Development and testing of lower VOC
content (higher solids) EC/CC coatings are being done, however, by automobile
manufacturers and coating suppliers.
Following the application of the topcoat, the body goes to the trim
operation area, where vehicle assembly is completed. The fln*1 step of the
surface coating operation is generally the final repair process, in which
damaged coating is repaired in a spray booth and is air dried or baked in a
low temperature oven to prevent damage of heat sensitive plastic parts added
in the trim operation area.
Emissions and Controls - Volatile organic compounds (VOC) are the major
pollutants from surface coating operations. Potential VOC emitting oper-
ations are shown in Figure A.2.2.8-1. The application and curing of the
prime coat, guide coat and topcoat account for 50 to 80 percent of the VOC
emitted from assembly plants. Final topcoat repair, cleanup, and miscella-
neous sources such as the coating of small component parts and application
of sealants, account for the remaining 20 percent. Approximately 75 to 90
percent of the VOC emitted during the application and curing process is
emitted from the spray booth and flashoff area, and 10 to 25 percent from
the bake oven. This emissions split is heavily dependent on the types of
8/82 Evaporation Loss Sources 4.2.2.8-3
-------
TABLE A. 2. 2. 8-1. EMISSION FACTORS FOR AUTOMOBILE AND
TRUCK SURFACE COATING OPERATIONS3
EMISSION FACiOK RATING: C
DVTY.
Automobile
Coating kg(lb)
per vehicle
Prlae Coat
Solventborne
apray
Cathodlc
electrodeposltlon
Gulds Coat
Solventborne spray
Vaterborne spray
Topcoat
Lacquer
Dispersion lacquer
Enamel
Baaecoat/claar coat
Uaterborne
6.61
(14.54)
.21
(.45)
1.89
(4.16)
.68
(1.50)
21.96
(48.31)
14.50
(31.90)
7.08
(15.58)
6.05
(13.32)
2.25
(4.95)
of VOC
per hour
363
(799)
12
(?5)
104
229
38
(83)
1208
(2657)
798
(175O
390
(857)
333
(732)
124
(273)
Light Put} TrucV
kg(lb) of VOC
per vehicle per hour
19.27
(42.39)
.27
(.58)
6.38
(14.04)
2.3
(5.06)
MA
HA
17.71
(38. V6)
18.91
(41.59)
7.03
(15.47)
.32
(1611)
10
(22)
243
(5341
87
(192)
NA
HA
673
(1480)
715
(1581)
267
(588)
All noanethanc VOC. Factora are calculated tiling the following equation
and the typical values of parao.^tera praaenced in Tables 4.2.2.U-2 and
4.2.2.8-3. KA • No: applicable.
- Av
Tf Vc
C|
Vr
Where: E • emission factor for VOC, OMB per vehicle (Ib/vehicle)
(exclueive of any .iddon control devices)
area coated per vehicle (ftz/vehlcle)
conversion factor: 1 ft/12,000 mil
T. • thicknvss of the dry coating film (nil)
V • VOC (crganic aolvant) cont-nt of coating as applied, less water
c (Ib VOC/gal coating, leas water)
C2 • conversion factor: 7.48 gallons/ft3
S - aollda in coating as applied, volune fraction (gal solids/gal
coating)
e_ - transfer efficiency fraction (fraction of total coating solid?
used which remains on coated parts)
Example: The VOC emissions per automobile from J cathodic electrodepoeited
prliw coat.
- , ,lrt. (650 ft')(1/12000)(0.6 mil) (1.2 Ib/gal-Hk'Q;
E nass of VOL • J •*-^—;—r
v (-8
- .45 ib VOC/vehlcle (.21 kg VOC/vehicle)
Base on an average line speed of 55 automoblles/hr.
cBaued on an average line speed of 38 llfht duty trucka/hr.
4.2.2.8-4
EMISSION FACTORS
J/82
-------
solvents used and on transfer efficiency. With improve 1 transfer effi-
ciencies Slid the newer coatings. It is expected that the percent of VOC
emitted from the spray booth and the flaahoff area will decrease, and the
percent of VOC emitted frpm the bake oven will remain iairly constant.
Higher solids coatings, with their slower solvents, will tend to have a
greater fraction of emissions from the bake oven.
Several factors affect the mass of VOC emitted per vehicle from surface
coating operations in the automotive Industry. Among these are:
VOC content of coatings (pounds of coating, less water)
Volume solids content of coating
Area coated per vehicle
Film thlr-rjiess
Transfer efficiency
The greater the quantity of VOC in the coating composition, the greater will
be the emissions. Lacquers having 12 to 18 volume percent solids are higher
In VOC than enamels having 24 to 33 volume percent solids. Bnissions *re
also influenced by the area of the parts being coated, the coating thickness,
the configuration of the part and the application technique.
The transfer efficiency (fraction of the solids in the total consumed
coating which remains on the part) varies with the type of application tech-
nique. Transfer efficiency for typical air atomized spraying ranges from 30
to 50 percent. The range for electrostatic spraying, an application method
that uses an electrical potential to increase transfer efficiency of the
coating solids, is from 60 to 95 percent. Both air atomized and electro-
static spray equipment may be used In the same spray booth.
Several types of control techniques are available to reduce VOC
emissions from automobile and light duty truck surface coating operations.
These methods can be broadly categorized as either control devices or new
coating and application systems. Control devices reduce emissions by either
recovering or destroying VOC before it is discharged into the ambient air.
Such techniques include thermal and catalytic incinerators on bake ovens,
and carbon adsorbers on spray boothn. New coatings with relatively low VOC
levels can be used In place of high VOC content coatings. Such coating
systems include electrodepositlon of waterborne prime coatings, and for top
coats, air spray of waterborne enamels and air or electrostatic spray of
high solids, solventborne enamels and powder coatings. Improvements In me
transfer efficiency decrease the amount of costing which must be used to
achieve a given film thickness, thereby reducing emissions of VOC to the
ambient air.
Calculation of VOC emissions for representative conditions provides the
emission factors in Table A.2.2,8-1. The factors were calculated with the
typical value of parameters presented in Tables 4.2.2.8-2 and 4.2.2.3-3.
The valuer for the various parameters for automobiles and light duty trucks
represent average conditions existing in the automobile and light duty truck
Industry in 1980. A more accurate estimate of VOC emissions can be calcu-
lated with the equation in Table 4.2.2.8-1 and with site-specific values for
the various parameters.
8/82 Evaporation Loss Sources 4.2.2.!}-1?
-------
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00
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TABLE 4.2.2.8-2. PARAMETERS FOP. THE AUTOMOBILE SURFACE COATING INDUSTRY3
Application
Prime Coat
Solventborne spray
Cath'jdlc elec trodeposit ion
HuMe Coat
Solventborne spray
Wacerborne spray
Topcoat
Solventborne spray
Lacquer
Dispersion lacquer
Fna>el
Base coat/clear coat
Base coat
Clear coat
Wnterborne spray
Area Coated
per vehicle,
ft2
450
(220-570)
850
O6U-1060)
200
(1/0-280)
200
(170-280)
2-'<0
(170-280)
240
(170-280)
240
(1 70-280)
240
240
(170-2 BO)
240
(170-280)
240
(170-280)
Film
Thickness,
nil
0.8
(0.3-2.5)
0.6
(0.5-u.S)
0.8
(0.5-1.5)
0.8
(O.S-2.0)
2.5
(1.0-3.0)
? 5
•!i .C-J.O)
2.5
(1.0-3.0)
Z.'j
1.0
(0.8-1.0)
1.5
(1.2-1.5)
7.2
(1.0-2.5)
VOC Content,
Ib/gal-HjO
5.7
(4.2-6.0)
1.2
(1.2-1.5)
5.0
(3.0-5.6)
2.8
(2.6-3.0)
6.2
<5.8-6.6)
5.8
(4.9-5.8)
5.0
(3.0-5.6)
4.7
5.6
(1.4-6.4)
4.0
(3.0-5.1)
2.8
(2.6-3.0)
VoluBc Fraction Solids,
0.22
(.20-. 35)
0.84
(.B4-.87)
0.30
(.25-. 55)
0.62
(.60-.6S)
0.12
(.10-. 13)
0.17
(.17-. 27)
0.30
(.23-. 55)
0.33
0.20
(.1J-.48)
0.42
(.30-. 54)
0.62
(.60-. 65)
Transfer
Efficiency,
i
40
OS-5U)
ICO
(85-100)
40
(35-65)
30
(25-40)
40
v 30-65)
40
(30-65)
40
(30-65)
40
40
(30-50)
40
(30-65)
I"
(25-40)
All valuta for coatings as applied, except for VOC content .ind volioe fraction solids which are for coatings au applied
Ranges in parentheses, l^nw VOC content (higli solids) base coat/clear coats are still undergoing testing and
Composite of base ueat and clear coat.
ilnua water.
-------
TABLE 4.2.2.8-3. PARAMETERS FOR THE LIGHT DOTY TRUCK SURFACE COATING INDUSTRY
Application
Priae Coat
Solvent borne spray
Cathodlc eleccrodepositlon
Guide Co ft.
Solventbarne apray
Uaterbarne spray
Tupcoat
Solves tbo me apray
Eiwuel
Baae coat/el«tr coat
Ba*-65)
40
40
(30-50)
40
(30-65)
30
(25-M»
3D
I
All values are Cor coatings a* applied, except for VOC content and voluaa fraction aollda vhich are for coating* mm applied mlaoB water.
.Range* in parentheala. Low VOC concent (high aollda) baa* coat/clear coata are at111 tndergolag tcatlng and davclopvaot.
CoBpoalte of typical baae coat and clear coaC.
-------
Emission factors are not available for final topcoat repair, cleanup,
coating of snail parts and application of sealants.
References for Section 4.2.2.8
1. Control of Volatile Organic Emissions from Existing L'tatlon^ry
Sources - Volume I1: Surface Coating of Cana. Coils. Paper Fabrics^
Automobiles, and Light Duty Trucks, EPA-450/2-77-008, U.S. Environmental
Protection Agency, Research Tiiangle Park, NC, May 1977.
2. Study To Determine Capabilities To Meet Federal EPA Guidelines for
Volatile Organic Compound Emissions. General Motors Corporarlon,
Detroit, Ml, November 1978.
3- Automobileand light Duty Truck Surface Coating Operations - Background
Information for Propped Standarda, EPA-450/3-79-030, U.S. Environmental
Protection Agency, K, ,earch Triangle Park, NC, September 1979.
4. Written communication from D. A. Frank, General Motors Corporation,
Warren, MI, to H. J, Modetz, Acurex Corporation, Morrisville, NC,
April 14, 1981.
4.2.2.8-8 EMISSION FACTORS 8/82
-------
4.2.2.9 PRESSURE SF.NSITIVE TAPES AND LABELS
General - The coating of pressure sensitive tapes and labels
(PSTL) Is an operation In which s.jnri backing material (^aper, cloth
or filir.) is coated to create a tape or label product that sticks on
contact. The term "pressure sensitive" Indicates tha'. the adhesive
bond is formed on contact, without wetting, heating or adding a
curing agent.
The products manufactured by the FSTT. surface coating industry
may have several different types of coatings applied to them. The
two primary types of coatings are adhesives and releases. Adhesive
coating is a necessary step \n the manufacture of almost all PSTL
products. It is generally t.'ie heaviest coating (typically 0.051 kg/m2,
or 0.011 lb/ft2) and therefore has the highest level of solvent
emissions (generally 85 to 95 percent of total line emissions).
Release coatings are applied to the backside of tape or to the
mounting paper of labels. The function of release coating is to
allow smooth and easy unrolling of a tape or removal of a label
from mounting paper. Release coatings are applied in a very thin
coat (typically 0.00081 kg/m2, or 0.00017 lb/ft2). This thin
coating produces less emissions than does a comparable size adhesive
coating line.
Five basic coating processes can be used to apply both adhesive
and release coatings:
solvent base coaling
waterborne (emulsion) coating
100 percent solids (hot melt) coating
calender coating
prepolymer coating
A solvent base coating process Is useil *o produce 80 to 85
percent of all products in the PSTL industry, and essentially all
of the solvenr emissions from the industry res-ilt from solvent base
coating. Because of its broad application ant' significant emissions,
solvent base coating of PSTL products is discussed in greater
detail.
1-2 5
Process Description ' - Solvent base surface coating is conceptually
a simple process. A continuous roll of backing material (called
the web) is unrolled, coated, dried and rolled again. A typical
solvent base coating line is shown in Figure 4.2,2.9-1. Large
lines in this industry have typical web widths of '52 centimeters
(*>G in), whilt! small lines are generally 48 centimeters (24 in).
Line speeds vary substantially, from three to 305 rasters per
8/82 Evaporation Loss Sources 4.2.2.9-1
-------
OO
or
ro
t
Clean Exhaust Gas
•n
o
'•5
t>
O
0>
0>
vt
Q
n
1C
*-
•
N)
•
ro
i
ro
Heated Air
from Burner
Unwino
Adhesive or
Release Coater
X.
Control Device
Drying Oven F.xhausts
Hot Air Nozzles
ll lT if
Q Q O Q
Drying Oven
Fugitive Solvent
Emissions
Solvent in the Web
Rewind
Figure 4.2.2.9-1. Diagram of a Pressure Sensitive Tape and Label Coating Line
-------
ninute (10 - 1000 ft/min). To initiate the coating process the
continuous wto material IB unwound from Its roll. It travels to a
coating head, where the solvent base coating formulation is applied.
These formulations have specified levels of solvent and coating
sclids by weight. Solvent base adhesive formulations contain
approximately 67 weight percent solvent and 33 weight percent
coating solids. Solvent base releases average about 95 weight
percent solvent and 5 weight percent coating solids. Solvents used
include toluene, xylene, heptane, hetane and methyl ethyl ketone.
The coating solids portion of the formulations consists of elastomers
(natural rubber, styrene-butadlene rubber, polyaorylatee), tacklfylng
resins (polyterpenes, rosins, petroleum hydrocarbon resins, asphalts),
plasticlzer* (phthalate esters, polybutenes, mineral oil), and
fillers (zinc oxide, silica, clay).
The order of application is generally release coat, primer
coat (if any) and adhesive coat. A web must always have a release
coat before the adhesive can be applied. Primer coats are not
required on all products, generally being applied to improve the
performance of the adhesive.
Three basic categories of coating heads &re used in the PSTL
Industry, The type of coating head used has a great effect on the
quality of the coated product, but only a minor effect on overall
emissions. The first type operates by applying coating to the web
and scraping excess off to a desired thickness. Examples of this
type of coater are the knife coater, blade coater and metering rod
coater. The second category of coating head meters on a specific
amount of coating. Cravure and reverse roll coaters are the meat
common examples. The third category of coating head does not
actually apply a surface coating, but rather It saturates the web
backing. The most common example In this category is v:he dip and
squeeze coater.
After solvent base coatings have been applied, the web moves
into the drying oven where the solvents are evaporated from the
web. The important characteristics of the drying oven operation
are:
source of heat
temperature profile
residence time
allowable hydrocarbon concentration in the dryer
oven air circulation
Two basic types of heattng are used In conventional drying
ovens, direct and indirect. Direct heating routes the hot combustion
gases (blended with ambient air to the proper temperature) directly
8/62 Evaporation Loss Sources 4.2.2.9-3
-------
into the drying zone. With Indirect heating, the Incoming oven air
stream Is heated In a heat exchanger with steam or hot combustion
gases but does not physically mix with then. Direct fired ovens
are more common In the PSTL industry because of their higher
thermal efficiency. Indirect heated ovens are less energy efficient
in both the production of steam and the heat transfer in the
exchanger.
Drying oven temperature control is an important consideration
in PSTL production. The oven temperature must be above tne boiling
point of the applied solvent. However, ihe Temperature profile
must be controlled by using mult Ironed ovens. Coating flaws known
us "craters" or "fish eyes" will develop if the Initial drying
proceeds too quickly. These ovens are physically divided Into
several sections, each with Its own hot air supply and exhaust. By
keeping the temp^rat'jie of the first zone low, and then gradually
Increasing it in subsequent zones, uniform drying can be accomplished
without flaws. After exiting the drying oven, the continuous web
is woun] on a roll, and the coating process 1s complete.
Emissions >d~ - The only pollutants emitted in significant
quantities from solvent base coating of pressure sensitive tapes
and labels are volatile organic compounds (VOC) from solvent
evaporation. In an uncontrolled facility, essentially all of the
solvent used in the coating formulation Is emitted to the atmosphere.
Of these uncontrolled emissions, 80 to 'J5 percent -ve emitted with
the drying oven exhaust. Some solvent (from zero to five percent)
can remain in the final coated product, although this solvent will
eventually evaporate into the atmosphere. Ihe remainder of applied
solvent is lost from a number of small sources as fugitive emissions.
The major VOC emission points in a PSTL .Turface coating operation
are indicated in Figure A.2.2.9-1.
There are also VOC losses from solvent storage and handling,
equipment cleaning, miscellaneous spills, arid coating formulation
mixing tanks. These emissions are not addressed here, as *hese
sources have a comparatively small quantity of emissions.
Fugitive solvent emissions during the coating process come.
from the evaporative loss of solvent around the coating head and
fron tin- exposed vet web prior to its entering the drying oven.
The magnitude of these losses is determined by the width of the
web, the line speed, the volatility and temperature of the solvent,
and the air turbulence In the coating area.
Two factors which directly determine total line emissions are
the weight (thickness) of the applied coating on the web and the
solvent/solids ratio of the coating formulations. For coating
.',.2.2.9-4 EMISSION FACTORS fl/87
-------
formulations with a constant solvent/solids ratio during coating,
any increases in coating weight would produce higher levels of VOC
emissions. The solver.:/solids ratio in coating formulations is rut
constant industrywide. This ratio varies widely among products.
If a coating weight is constant, greater emissions will be produced
by increasing the weight percont. solvent of a particular formulation.
These two operating parameters, combined with line speed, line
width and solvent volatility, produce a number of potentional mass
emission situations. Table 4.2.2.9-1 presents emission factors for
controlled and uncontrolled PSTL surface coating operations. The
potential amount of VOC emissions from the coating process is equal
to the tota1 amount of solvent applied at the coating head.
1 6—18
Controls ' - The complete air pollution control system for a
modern pressure sensitive -.ape or label surface coating facility
consists of two sections, the solvent vapor capture system and the
emission control device. The capture system collects VOC vapors
from the coating head, the w<_t web and the drying oven. The captured
vapors are directed to a control device to be either recovered (ay
liquid solvent) or destroyed. As an alternate emission control
technique, the PSTL Industry Is also using low-VOC content coatings
to reduce their VOC emissions. Waterbornc and hot melt coatings
and radiaTion cured prepn]ymer& are examples of therj low-VOC
content coatings. Flmlsslens of VOC from such coitiiigs are negligible
or zero. Low-VOC content coatings are not unlverpally applicable
to the PSTL industry, but about 25 percent of the production in
this industry is presently usirvg thete innovative coatings.
Capture Systems - In i typical PSTL surface routing facility,
80 to 95 percent of VOC emissions from the coating process is
captured in the coating liv.e drying ovens. ".;'s are used to
direct drying oven emissions to a control device. In sc-ne ij di
a portion of the drying oven exhaust is re.circulared into the oven
instead of to a control device. Keeirculatlon is used to Increase
the VOC concentration of th« rtr"lnp( oven jxhaust gases going to the
control device.
Another important aspect of capture in a PSTL facility
involves fugitive VOC emissions. Three techniques can be used to
collect fugitive VOC emissions from PSTL coating lines. The first
involves the use of floor sweeps and/or hooding systems around the
coating head and exposed coated web. Fugitive emissions collected
in the hoods can be directed into the drying oven and on to a
control device, or they can be sent directly to the control device.
The second capture technique involves enclosing the entire coating
line or the coating application and flashoff areas. By maintaining
8/82 Evaporation Loss Sources 4.2.2.9-5
-------
TABLE 4.2.2.9-1. EMISSION FACTORS FOR PRESSURE SENSITIVE
TAPE AND LABEL SURFACE COATING OPERATIONS
EMISSION FACTOR RATING: C
Nonnethane VOC*
Emission Poin»a
Drying Oven Exhaust
Fugitives0
Product Retention
Control Device*
Total Emissions
Uncontrolled
kg/kg
as/ib)
0.80-0.95
0.01-0.13
0.01-0.05
1.0
85Z Control
kg/leg
(Ib/lb)
0.01-0.095
0.01-0.05
0.045
0.15
90Z Control
kg/kg
Clb/lb)
____
0.0025-0.0425
0.01-0.03
0.0475
0.10
Expressed as the mass of volatile organic covpounds fVOG) enittod par
BUSS of total solvent vaed. Solvant !• assumed to r.On»i»t entirely of VOC.
References 1, 6-7, 9. Dryer axhauat aalavlon* dapend oa coating line
oparatlag speed, Craquaocy of line downline, coating composition and
oven design.
by difference between total emissions and other point
lourcer . Magnitude la determined by aize of the lini equipment,
line speed, volatility and tftoperaeura of the solvents, and air
turbulence in the coating area.
Solvenc in the product eventually evaporates Into
References 6-3.
the acnosphere,
*Refarenced 1, 10, 17-13. Eoiasions ara reaidual content in captured
solvent ladan air vented aftar treatment. Controlled coating line
ami 3 a ions ara ba£«d on an overall reduction efficiency vhich is equal
to ca.pt art efficiency times control device efficiency. Foe 852
coarrol, rapture efficiency is 902 with a 95Z efficient control device.
For 90Z coatrol, capture efficiency la 95Z vith a 95 X efficient control
device .
Values aaaun" that uncontrolled coating lines eventually emit 100Z
of all solvents used.
4.2.2.9-6
EMISSION FACTORb
P/82
-------
a slight negative pressure within the enclosure, a capture efficiency
of 100 percent Is theoretically possible. The captured emissions
are directed by fans into the oven or to a control device. The
third capture technique Is an expanded form of total enclosure.
The entire building or structure which houses the coating line acts
aa an enclosure. The entire room air is vented to a control
device. The maintenance of a slight negative pressure ensures that
very few emissions escape the room.
The efficiency of any vapor capture system Is highly dependent
on its design and its degree of integration with the coating line
equipment configuration. The design of any system must allow safe
and adequate access to the coating line equipment for maintenance.
The system mu^t alsc be designed to protect workers from exposure
to unhealthy concentrations of the organic solvents used in the
surface coating processes. The efficiency of a well designed
combined dryer exhaust and fugitive capture system Is 95 percent.
Control Devices - The control devices and/or techniques that
may be used to control captured VOC emissions can be classified
Into two categories, solvent recovery and solvent destruction.
Fixed bed carbon adsorption Is the primary solvent recovery technique
used In this Industry. In fixed bed adsorption, the solvent
vapors are adsorbed onto the surface of activated carbon, and the
solvent is regenerated by steam. Solvent recovered in this manner
may be reused In the coating process or sold to a reclaimer. The
efficiency of carbon adsorption systems can reach 98 percent, but a
95 percent efficiency Is raor* characteristic of continuous long
term operation.
The primary solvent destruction technique used in the PSTL
industry is thermal incineration, which can be t's high as 99
percent efficient. However, operating experience with Incineration
devices has shown that 95 percent efficiency Is more characteristic.
Catalytic incineration could be used to control VOC emissions with
the same success as thermal Incineration, but no catalytic devices
have been found in the industry.
The efficiencies of carbon adsorption and thermal Incineration
control techniques on PSTL coating VOC emissions have been determined
to be equal. Control device emission factors presented in Table
A.2,2.9-1 represent the residual VOC content in the exhaust air
after treatment.
The overall emission reduction efficiency for VOC emission
control systems is equal to the capture efficiency times the
control device efficiency. Emission factors for two control
levels are presented in Table 4.2.2.9-1. The 85 percent control
8/82 Evaporation Loss Sources 4.2.2.9-7
-------
level represents 90 percent capture with a 95 percent efficient
control device. The 90 percent control level represents 95 percent
capture with a 95 percent efficient control device.
References for Section 4.2.2.9
1. The Pressure Sensitive Tape and Label Surface Coating Industry -
Background Information Document, EPA-450/3-80-003a, U. S.
Environmental Protection Agency, Research Triangle Park, NC,
September 1980.
2. State of California Tape and Label Coaters Survey, California
Air Resources Board, Sacramento, CA, April 1978. Confidential.
3. M R. Rifi, "Water Based Pressure Sensitive Adhesives, Structure
vs. Performance", presented at Technical Meeting on Water Baaed
Systems, Chicago, IL, June 21-22, 1978.
4. Pressure S^naitive Products and Adheaives Market, Frost and
Sullivan Inc., Publication No. 614, New York, NY, November
1978.
5. Silicone Release Questionnaire, Radian Corporation, Durham,
NC, May 4, 1979. Confidential.
6. Written communication from Frank Phillips, 3M Conpany, to G.
E. Harris, Radian Corporation, Durham, NC, October 5, 1978.
Confidential.
7. Written communication from R. F. Baxter, Avery International,
to G. E. Harris, Radian Corporation, Durham, NC, October 16,
1978. Confidential.
8. G. E. Harris, "Plant Trip Report, Shuford Mills, Hickory, NC",
Radian Corporation, Durham, NC, July 28, 1978.
9. T. P. Nelson, "Plant Trip Report, Avery International, Painesville,
OH", Radian Corporation, Durham, NC, July 26, 1979.
10. Control of Volatile Organic Emissions frof Existing Stationary
Sourcea - Volume II: Surface Coating of Cans, Coils. Paper,
Fabrics. Automobiles, and Ligt.t Duty Trucks. EPA-450/2-77-008.
U. S. Environmental Protection Agency, Research Triangle Park,
NC, May 1977.
11. Ben Milazzo, "Pressure Sensitive Tapes", Adhesives Age,
22:27-28, March 1979.
4.2.2.9-8 EMISSION FACTORS g/82
-------
12. T. P. Nelson, "Trip Report for Pressure Sensitive Adhesives -
Adhesives Research, Glen Rock, PA", Radian Corporation. Durham,
NC February 16, 1979.
13. T. P. Nelson, "Trip Report for Pressure Sensitive Adhesives -
Precoat Metals, St. Louis, MO", Radian Corporation, Durham, NC
August 28, 1979.
14. G. W. Brooks, "Trip Report for Pressure Sensitive Adhesives -
E. J. Galsser, Incorporated, Stamford, CT", Radian Corporation,
Durham, NC, September 12, 1979.
15. Written communication from D. C. Mascone to J. R. Farmer,
Office of Air Quality Planning and Standards, U. S. Environmental
Protection Agency, Research Triangle Park, NC, June 11, 1980.
16. Written communication from R. E. Miller, Adheslvee Research,
Incorporated, to T. P. Nelson, Radian Corporation, Durham, NC,
June 18, 1979.
17. A, F. Sidlow, Source Test Report Conducted at Fasson Products,
Division of Avery Corporation^ Cucamonga, CA, San Bernardino
County Air Pollution Control District, San Bernardino, CA,
January 26, 1972.
18. R. Milner, et al., Source Teat Report Conducted at Avery
Label Company. Monrovia. CA, Los Angeles Air Pollution Control
District, Los Angeles, CA, March 18, 1975.
8/82 Evaporation Loss Sources 4.2.2.9-9
-------
A.2.2.10 METAL COIL SURFACE COATING
General1"^ _ Metal coil surface coating (coll coating) is the linear process
by which protective or decorative organic coatings are applied to flat metal
sheet or strip packaged in rolls or coils. Although the physical
configurations of coil coating lines differ from one installation to another,
the operations generally follow a set pattern. Metal strip is uncoiled at the
entry to a coating line and is passed through a wet section, where the metal
is thoroughly cleaned and is given a chemical treatment to inhibit rust and to
propote coatings adhesion to the metal surface. In some Installations, the
wet section contains an electrogalvanizing operation. Then the metal strip i«
dried and sent through a coating application station, where rollers v.oat one
or both sides of the metal strip. The strip then passes through an oven where
the coatings art; dritd and cured. As the strip exits the oven, it is cooled
by a water spray and again dried. If the line is a tanden line, there is
first the application of a prime coat, followed by another of top or finish
coat. The second coat is also dried and cured in an oven, and the strip Is
again cooled dad dried before being rewound into a coll and packaged for
shipment or further processing. Most coil coating lines have accumulators at
the entry and exit that permit continuous metal strip movetaent through the
coating process while a new coll is mounted at the entry or a full coll
removed at the exit. Figure 4.2.2,10-1 is a flow diagram of a coil coating
line.
Coil coating lines process metal in widths ranging from a few centimeters
to 183 centimeters (72 Inches), and in thicknesses of from 0.018 to 0.229
centimeters (0.007 to 0.090 Inches). The speed of the metal strip through the
line is as high as 3.6 meters per second (700 feet per minute) on some of the
newer lines•
A wide variety of coating formulations is used by the coil coating
Industry. The more prevalent coating types Include polyesters, acrylics,
polyfluorocarbons, alkyds, vinyls and plastlsols. About 85 percent of the
coatings used are organic solvent base and hava solvent contents ringing from
near 0 to 80 volume percent, wi_h the prevalent range being 40 to 60 volunr
percent. Most of the remaining 15 percent of coatings are waterborne, but
they contain organic solvent in the range of 2 to 15 volume percent. High
solids coatings, In the form of plastlsols, organosols and powders, are also
used to some extent by the Industry, but the hardware Is different for powder
applications.
The solvents moat often used In the coil coating industry include xylene,
toluene, methyl ethyl ketone, Cellosolve Acetate (TM), butanol, diacetone
alcohol, Cellosolve (TM), Butyl Ceilosolve (TM), Sol^esso 100 and 150 (TM),
isophorone, butyl carbinol, mineral spirits, ethanol, nitropropane,
tetrahydrofuran, Panasolve (TM), methyl iaobutyl ketone, Hisol 100 (TM),
Tenneco T-125 (TM), isopropanol, and dilsoamyl ketone.
Coil cor.ti.ig operations can be classified in one of two operating
categories, toil coaters and captive coaters. The toll coater is a service
coater wlir- works for many customers according to the needs and specifications
8/82 Evaporation Loss Sources A.2.2.10-1
-------
ISJ
NJ
O
Pi
1-1
en
t/l
I—I
O
z
n
•OLvftaiam
*m
ACCUMULATOR
•DLVUITUMi
\
\
^UfUUL \
0/1
\
X TovcoaT
\ COATWC
SixWS
ACCUMULATOR
^J
ntKU MUMt TOPCOAT "OrCOAT TOKCMT
COATMC OVIM OIMNCM COATMO OVCW OU»CH
AJIEA
OD
CD
K>
Figure 4.2.2.10-1- Flow Diagram of model coil coating line.
-------
of each. The coated metal Is delivered to the customer, who forms the end
produces. Toll coaters use many different coating formulations and normally
use mostly organic solvent base coatings. Major markets for toll coating
operations Include the transportation industry, the construction Industry and
appliance, furniture and container manufacturers. The captive coater is
normally one operation in a manufacturing process. Many steel and aluminum
companies have their own coil coating operations, where the metal they produce
is coated and then formed into end products. Captive coaters are much more
likely to use water base coatings because the metal coated is often used for
only a few end products. Building products such as aluminum siding ar-i one cf
the more important useu of waterborne metal coatings.
Emission and Controls^"^ - Volatile organic compounds (VOC) are the aajor
pollutanrj emitted from metal coil surface coating operations. Specific
operations that emit VOC are the coating application station, the curing oven
and the quench area. These are identified in Figure 4.2.2.10-1. VOC
emissions result from the evaporation of organic solvents contained in the
coating. The percentage of total VOC emissions given off at each emission
point varies from one installation to another, but, on the average, about 8
percent is given off at the coating application station, 90 percent the oven
and 2 percent the quench area. On most coating lines, the coating application
station is enclosed or hooded to capture fugitive emissions and to direct them
into the oven. The quench is an enclosed operation located immediately
adjacent to the exit end of the oven so that a large fraction of the emissions
glveu off at the quench is captured and directed into the oven by the oven
ventilating air. In operations such as thtse, approximately 95 percent of the
total emissions is exhausted by the oven, and the remaining 5 percent escapes
as fugitive emissions.
The rate of VOC emissions from individual coil coating lines may vary
widely from one installation to another. Factors that iftect the emission
rate include VOC content of coatings as applied, VOC density, area of metal
coated, solids content of coatings as applied, thickness of the applied
coating and number of :oats applied. Because the; coatings are applied by
roller coating, transfer efficiency is generally considered to approach 100
percent and therefore does not affect the emission rate.
Two emission control techniques are widespread in the coil coating
industry, incineration and use c? low VOC content coatings. Incinerators may
be either thermal or catalytic, both of which have been demonstrated to
achieve consistently a VOC destruction efficiency of 95 percent or greater.
When used with coating rooms or hoody to capture fugitive emissions,
incineration systems can reduce overall emissions by 90 percent or more.
Waterborne coatings are the only low V'O'" content coating technology that
is used to a significant extent in tt.e coil coating industry. These coatings
have substantially lower VOC emissions than must, of the organic solventborne
coatings. Waterborne coatings are used as an emission control technique most
often by installations that coat metal for only a few products, such as
building materials. Many such coaters are caotlve to the firm that produces
and sells the products fabricated from the coaled coil. Because waterborne
8/82 Evaporation Loss Sources 4.2.2.10-3
-------
TABLE 4.2.2.10-1. VOC EMISSION FACTORS FOR COIL COATING*
EMISSION FACTOR RATING: C
Coatings
Solventborne
uncontrolled
controlled
Waterborne
kg/hr (Ib/hr)
Average
303
(669)
30
( 67)
50
(111)
Normal
50 -
(110 -
5 -
(11 -
3 -
C/ ~
range
1,798
3,964)
isn
39O
337
743)
kg/m2 (lb/ft2)
Average
0.060
(0.012)
0.0060
(0.0012)
0.0108
(0.0021)
Normal
0.027
(0.006
0.0027
(0.0006
0.0011
(0.0003
range
- 0.160
- 0.033)
- 0.0160
- 0.0033)
- 0.0301
- 0.0062)
*A11 nonnethane VOC. Factors are calculated using the following equatlona and
the operating parameters given In Table 4.2.2.10-2.
(1)
E -
0.623 ATVD
where
E - maSB of VOC emissions per hour (Ib/hr)
A - Area of metal coated per hour (ft^)
- Line speed (ft/min) x strip width (ft) x 60 mln/hr
V - VOC content of coatings (fraction by volume)
D • VOC Density 'v assumed to be 7.36 Ib/gal)
S - Solids content of coatings (traction by volume)
T - Total dry illm thickness of coatings applied (in)
The constant 0.623 represents conversion factors of 7.4B gal/ft- divided
by the conversion fector of 12 in/ft.
wheri?
(2)
mass of VOC emissions per unit area coated.
''Computed by assuming a 90 percent overall control efficiency (95 percent
capture and 95 percent removal by the control device).
4.2.2.10-4
EMISSION FACTORS
8/82
-------
TABLE A.2.2.10-2. OPERATING PARAMETERS KOR SMALL, MEDIUM AND
LARGE COIL COATING LINESa
Solventborne coatings
Lin..'
SiZi
Smell
Me used to estimate emissions from individual sources.
CA]1 three values of VOC content and solids content were used in the
calculation of emission factors for each plant size to ylve maximum, ninimura
ar.d average enission factors.
coatings have uot been developed for many coated metal coil uses, most toll
coeters use organic solventborne coatings and control their emissions by
incineration. Most newer incincerator installations use heat recovery to
reduce Lhe operating cost of an incineration system.
Emission factors fcr coil coating operations and the equations used to
coripute them are presented in Tsblc A.2.2.10-1. The values presented therein
represent maximum, minimum and average emissions from small, medium and large
co:.l coating lines. An average film thickness and an average solvent content
.'iru assumed to compute the average emission factor. Values for the VOC
content near the maximum and minimum used by the industry are assumed for the
calculations of maximum and minimum emission factors.
The emission factors in Table A.2.2.10-1 are useful in estimating VOC
eir.is.sions for a large sample of coll coating sources, but they may not be
8/82
Evaporation Loss Sources
4.2.2.10-5
-------
applicable Co individual plants. To estimate th* emissions from a specific
plant, operating parameters of the coll coating line should be obtained and
used In the equation given In the footnote to the Table. If different
coatings are used for prime and topcoats, separate calculations must be made
fur each coat. Operating parameters on which the emission f u-tors are based
are presented In Table 4.2.2.10-2.
References for Section 4.2.2.10
!• Metal Coil Surface Coating Industry - Background Information for Proposed
Standards, EPA-45U/3-80-035a, U.S. Environmental Protection Agency,
Research Triangle Park, NC, October 1980.
2. Control of Volatile Organic Emissions from Exist ing Stationary Sources,
Volume 11; Surface Coating ot Cans, Colls, Paper, Fabric.1;, Automobiles,
jind Light D"ty Trucks, EPA-450/2-77-OQ8, U.S. Environmental Protection
Agency, Research Triangle Park, NC, May 1977.
3. Unpublished survey of the Coil Coating Industry, Office of Water and
Waste Management, U.S. Environmental Protection Agency, Washington, DC,
1978.
4. Communication between Milton Wright, Research Triangle Institute,
Research Triangle Park, NC, and Bob Mormn, Glidden Paint Company,
Strongville, OH, June 27, 1979.
5. Coumunicatlon between Milton Wright, Research Triangle Institute,
Research Triangle Park, NC, and Jack Bates, DeSoto, Incorporated, Des
Plalnes, IL, June 25, 1980.
b. Communication between Milton Wright, Research Triangle Institute,
Research Triangle Park, NC, and M. W. Miller, DuPont Corporation,
Wilmington, DE, June 26, 1980.
7. Communication between Hilton Wright, Research Triangle Institute,
Research Triangle Park, NC, and H. B. Kinzley, Cook Paint and Varnish
Company, Detroit, MI, June 27, 1980.
8. Written communication from J. D. Pontius, Shcrwin Uilliams, Chicago, IL,
to J. Kearney, Research Triaiiglo Insrituie, Research Triangle Park, NC,
January 8, 1980.
9. Written communication from Dr. Maynard Sherwin, Union Carbide,
South Charleston., w;, to Milton Wright, Research Triangle Institute,
Research Triangle Park, NC, January 21, 1980.
10. Written communication from D. 0. Lawson, PPG Industries, Springfield, PA,
to Milton Wright, Research Triangle Institute, Research Triangle Park,
NC. February 8, 1980.
4.2.2.10-6 EMISSION FACTORS 8/82
-------
11. Written coamunlcatlor from National Coll Coaters Association,
Philadelphia, PA, to Office of Air Quality Planning and Standards, U.S.
Environmental Protection Agency, Research Triangle Park, NC, May 30,
1980.
12. Written communication from Paul Tlmmermar., Hanna Chemical Coatings
Corporation, Columbus, OH, to Hilton Wright, Research Triangle Institute,
Research Triangle Park, NC, July 1, 1980.
Evaporation Loss Sources 4.2.2.10-7
-------
4.2.2.11 LARGE APPLIANCE SURFACE COATING
General 1 - Large appliance surface coating is the application of protective or
decorative organic coatings to preformed large appliance parts. For this
discussion, large appliances are defined as any cetal range, oven, microwave
oven, refrigerator, freezer, washing machine, dryer, dishwasher, watar heater
or trash compactor.
Regardless ot the appliance, similar manufacturing operations are
involved. Coiled or sheec raeial is cut and stamped 1-to the propev shapes,
and the rvajor part:- weided together. The welded parts are ci«.aned with
organic degreasers or a caustic detergent (or both) to remove grease and mill
scale accumulated during handling, and the parts are then rinsed in one or
r.ore water rinses. fhls is often followed by a process to improve the grain
of the metal before treatment in a phosphate bath. Iron or zinc phosphate is
commonly used to deposit a microscopic matrix of crystalline phosphate on the
surface of the metal. This prcctsR provides corrosion resistance and
increases the surface area of the part, thereby allowing superior coating
adhesion. Often the highly reactive metal is protected vlth a rust inhibitor
to prevent rusting prior tu painting.
Two separate coatings have traditionally been applied to these prepared
appliance parts, a protective prime coating that also covers surface
imperfections and contributes to total coating thickness, and a final,
decorative top coac. Single coat systems, where only a prime coat or only a
top coat is applied, are becoming more common. For parts not exposed to
customer view, a prime coat alone may suffice. For exposed parts, a
protective coating may be formulated and applied so as to act as the top coat.
There are many different application techniques in the large appliance
industry, including manual, automatic and electrostatic spray operations, and
several dipping methods. Selection of a particular ruethod depends largely
upon the geometry and use of the po^t, the production rate, and the type of
coat-ing being used. Typical application of these coating methods Is shown in
Figure 4.2.2.11-1.
A wide variety nf coating foimulations Is used by the large appliance
industry. The prevalent coating types include eooxles, epoxy/acryllcs,
acrylics and polyester enamels. Liquid coatings may use either an organic
solvent or wuter as the main carrier for the paint solldi .
Waterborne coatings are of three major classes, water solutions, vater
tmulsionc and water dispersions. All of the waterborne coatings, however,
contain a sn-all amount (up to 20 volume percent) of organic solvent thst Acts
aa a stabilizing, dispersing or emulsifying agent. Waterborne systems offer
some advantages over organic solvent systems. They do not exhibit as great an
increase in viscosity with increasing molecular weight of solUs, they are
nonclamjiable, and they have limited toxicity. But because of the relatively
slow evaooration rate of water, ic Is difficult to achieve a smooth Finish
with waterborne coatings. A bumpy "orange peel" surface often results. For
this ri-.ason, their main use in the large appliance Industry is ?s prime coats.
5/83 Evaporation Loss Sources 4.2.2.11-1
-------
r»ir«ct-To-M«tal Top Coot
o
3
2L
2
voc
voc
(flarfioff)
VOC
VOC
J_
Spray
Parts
Interior
Claaniing and
Pretrcatrnent
Dryoff
Oven
Electro-
Deposition
S1 Parts
n
g
5"
VOC
i
Flowcoat
or
Dip Coat
Prime Coat
To Assembly
w
00
Figure 4.2.2.11-1. Typical coating application methods in the large appliance industry.
-------
While conventional organic solventborne coatings also arc- used for prime
coats, they predominate as top coats. This is due in large part to ihe
controllability of the finish and the amenability of chese materials to
application by electrostatic spray techniques. The most common organic
solvents are ketones, eaters, ethers, aroraatics and alcohols. To obtain or
maintain certain application characteristics, solvents are often added to
coarings at the plant. The use of powder coatings for top coats is gaining
acceptance in the industry. These coatings, which are applied as a dry powder
and then fused in^u a continuous coating film through the use of heat, yield
negligible emit^ioas.
Emi9fri:>us and ControlBl~2 - Volatile organic compounds (VOC) are the major
pollutants emitted from large appliance surface coating operations. VOC from
evaporation of organic solvents contained in the coating are emitted in the
application fitat lor, the flashoff area and the oven. An estimated 80 percent
of total VOC emissions la given off in the application station and flashoff
area. Tie regaining 2U percent occurs in the oven. Because che emissions are
widely dis'ersec the use of capture tystems and control devices is not an
economically attractive means of controlling emissions. While both
incinerators and carbon adsorbers are technically feasible, none is known to
be used in production, and none is expected. Improvements in coating
formulation ard application efficiency are the major means of reducing
emissions.
Factors that affect the emission lace include the volume of coating used,
the coating's solids content, the coating's VOC content, and the VOC density.
The volume of coating used is a function of three additional variables, 1) the
area coated, 7) the coating thickness and 3) the application efficiency.
While a reduction in coating VOC content will reduce emissions, the
transfer efficiency with which the coating is applied (i.e., the volume
required to coat a given surface area) also has a direct bearing on the
emissions. A transfer efficiency of 60 percent means that 60 percent of the
coating solids consumed is deposited usefully onto appliance parts. The otter
40 percent is wasted overspray. With a specified WC cor.tont, an application
e/stem with a high transfer efficiency will have lover emission levels than.
will a system with a low transfer efficiency, because a smaller volume of
coating will coat the sane surface area. Since not every application method
can be used wlch all parts an 1 types of coating, transfer efficiencies in this
industry range from 40 to over 95 percent.
Although waterborne prime coats are becoming common, the trend for top
coats appears to ue toward use of "high solids" solventborne material,
generally 60 volume percent or greater solids. As different types of coatings
are required to meet different performance specifications, t. combination of
reduced coating VOC content and improved transfer efficiency is the most
common means of emission reduction.
In the absence of control systems that remove or destroy a known fraction
of the VOC prior to emission to the atmosphere, a material balance provides
the quickest and most accurate emissions estimate. An equation to calculate
Evaporation Los9 Sources 4.2.2.11-3
-------
emissions IB presented below. To the extent that the parameters of this
equation are known or can he determined, its use is encouraged. In the ;vent
that both a prime coat and a top coaL are used, the emissions from each mist
be calculated separately and added to enMinit-ra t-^t-ai omissions. Because of
the diversity of product mi" ::..u plant sizes, it ia difficult to prcvAde
emission factors fo~ "typical" facilities. Approximate values for ^ever*l of
the variables in Lhe equation fare provided, however.
where
(6.234 x 10-4) p A t V0 DQ
E + Ld D
VST
E - mass of VOC emission? per unit time (Ib/unit time)
P » units of production per unit time
A - area coated per unit of production (ft^)
t - dry coating thickness (mils)
V0 - proportion of VOC in the coating (volume fraction), as received*
D0 • density of VOC frolvent in the coating (Ib/gal), as received*
Vg » proportion of solids n ..he coating (volume fraction), as received*
T « transfer efficiency (fraction - the ratio of coating solids
deposited onto appliance parts tc the total amount of coating solids
used. S,i Table A.2.:.11-1).
Lj • volume of '/OC solvent added to the cot.ting per unit time (gal/unit
time).
Dj •=• density o* VOC solvent added (Ib/gal).
The constant 6.234 x 1C"-'4 is the product of two conversion factors:
S.333 x ID'5 ft 7.481 gal
..••-.. and .
mil ;t3
If all the data are not available to complete the above equation, the
following may be used as approximations:
VQ - 0.38
DQ - 7.36 :b/gal
Vs - 0.62
LJ •« 0 (assumes no polvent added fit the plant).
*If known, Vo, Do and Vs for :he coating as applied (i.e., diluted) may be
used In lieu of the values for the toating as received, and the term L^d
deleted.
4.2.2.11-;
EMISSION FACTORS
-------
TABLE 4.2.2.11-1. TRANSFER EFFICIENCIES
Transfer
Application MethoU Efficiency (T)
Air atomized spray 0.40
Airless spray 0.45
Manual electrostatic spray O.oO
Flow coat 0.85
Dip coat 0.85
Nonrelational automatic electrostatic spray 0.85
Rotating head automatic electrostatic ppray 0.90
Electrodeposition 0.95
Powder 0.95
TABLE 4.2.2.11-2. ARC.AS COATED AND COATING THICKNESS
Appliance
Compactor
Dishwasher
Dryjr
Freezer
Microwave oven
Range
Refrigerator
Washing machine
Water heater
Prime
A(ft2)
20
10
90
75
8
20
75
7H
20
Coat
t(mils)
0.5
0.5
0.6
0.5
0.5
0.5
0.5
0.6
0.5
Top
A(ft2)
20
10
30
75
8
30
75
25
20
Coat
t(mils)
0.8
0.8
1.2
C.8
0.8
0.0
0.8
1.2
0.8
5/83 Evaporation Loss Sources 4.2.2.11-5
-------
In Che absence of all operating data, --n emission estimate of 49.9 Mg (55
tons) of V'.C per year may be used for the average appliance plant. Because of
the large variation in emissions among plants (from leas than 10 to more than
225 Mg [10 to 250 tons] per year), caution la advised when this estimate Is
used for anything except approximations for a large geographical area. Most
of the known large appliance planes are la localities considered nonattainment
areas for achieving the national ambient air quality standard (NAAQS) for
ozone. The 49.9-Mg-per-year average is based on an emission limit of 2.8
Ib/VOC per gallon of coating (minus water), which is the limit recommended by
the Control Techniques Guideline (CTG) app'ltceble in those areas. For a plant
operating in an area where there are no emission limits, the emissions may be
four times greater than from an identical plant subject to the CTP recommended
limit.
References for Section 4.2.2.11
1. Industrial Surface Coating; Appliances- Background Informationfor
Proposed Standards, EPA-450/3-80-037a, U. S. Environmental Protection
Agency, Research Triangle Park, NC, November 1980.
2. Industrial Surface Coating; Large Appliances - Background Information
for Promulgated Standards^ EPA 450/3-80-037b, U. S. Environmental
Protection Agency, Research Triangle Park, NC, 27711, October 1962.
4.2.2.11-6 EMISSION FACTORS 5/83
-------
4.2.2.12 METAL FURNITURE SURFACE COATING
4.2.2.12.1 General
The metal furn: ^.ure surface coating process is a multistep operation
consisting of surface cleaning and coatings application and curing. Items
such as desks, chairs, tables, cabinets, bookcases and lockers are normally
fabricated from raw material to finished product in the same facility. The
industry uses primarily solventborne coatings, applied by spray, dip or flow
coating processes. Spray coating is the most common application technique
used. The components of spray coating lines vary from plant to plant but
generally consist of the following:
Three to five stage washer
Dryoff over
Spray booth
Flashoff area
Bake oven
Items to be coated are first cleaned in the washer to remove any grease,
oil or dirt from the surface. The washer generally consists of an alkaline
cleaning solution, a phosphate tr.-jttnent to improve surface adhesion charac-
teristics, and a hot water rinse. The items are then dried in an oven and
conveyed to the spray boclh, where the surface coating is applied. After this
application, the items are conveyed through the flashoff area to the bake
oven, where the surface coating is cured. A diagram of these consecutive
steps is presented in Figure 4.2.2.12-1. Although most metal furniture products
receive only one coat of paint, some facilities apply a prime coat before the
top coating to improve the corrosion resistance of the product. In these
cases, a separate spray booth and bake oven for application of the prime coat
are added to the line, following the dryoff oven.
The coatings used in the industry are primarily solventborne resins,
including acrylics, amines, vinyls and cellulosics. Some metallic coatings
are also used on office furniture. The solvents used are mixtures of aliphatics,
xylene, toluene and other aromatics. Typical coatings that have been used in
the industry contain 65 volume percent solvent and 35 volume percent solids.
Other types of coatings now being used in the industry are walerborne, powder
anu se'ventborne high solids coatings.
4 2.2.12.2 Emissions and Controls
Volatile organic compounds (VOC) from the evaporation of organic solvents
in t'ue coatings are the major pollutants from metal furniture surface coating
operations. Specific operations that emit VOC arc the coating application
process, the flashoff area md the bake oven. The percentage of total VOC
emissions given off at earli emission point varies from one installation to
another, but on the average spray coating line, about 40 percent is given off
at the application station, 30 percent in the flashtff area, and 30 percent in
the bake oven.
5/83 Evaporation Loss Sources 4.2.2.12-1
-------
ts)
Three stage washer
i
ts)
p>
EC
CO
I— I
g
5
n
H
en
Dryoff oven
Conveyor
Spray booth
Manual touchup spray booth
Flashoff
Bake oven
Figure 4.2.2.12-1. Example automated spray coating lines, with manual touchup.
-------
Factors affecting the quantity of VOC emitted from metal furniture surface
coating operations are the VOC content of the coatings applied, the solids
content of coatings as applied and the transfer efficiency. Knowledge of both
the VOC content and solids content of coatings is necessary in cases where the
coating contains other components, such as water.
The transfer efficiency (volume fraction of the solids in the total
consumed coating that remains on the part) varies with the application technique.
Transfer efficiency for standard (or ordinary) spraying range:; from 25 to
50 percent. The range for electrostatic spraying, a method that uses an
electrical potential to increase transfer efficiency of the coating solids, is
from 50 to 95 percent, depending on part size and shape. Powdei coating
systems normally captare and recirculate overspray material and, therefore,
are considered in terms of a "utilization rate" rather than a transfer efficiency.
Most facilities achieve a powder utilization rate of 90 to 95 percent.
Typical values for transfer efficiency with various application devices
are in Table A.2.2.12-1.
Two types of control techniques are available to reduce VOC emissions
from meta' furniture surface coating operations. The first technique maker
use of control devices such as carbon adsorbers and thermal or catalytic
incinerator^ to recover or destroy VOC before it is discharged into the ambient
air. These c ntrol methods are seldom used in the industry, however, because
the large volume of exhaust air and low concentrations of VOC in the exhaust
reduce their efficiency. The more prevalent control technique involves reducing
the total amount of VOC likely to be evaporated and emitted. This is accomplished
by use of low VOC content coatings and by improvements in transfer efficiency.
New coatings witii relatively low VOC levels can be used irsteaj of the traditional
high VOC content coatings. Examples of these new systems include waterborne
coatings, powder coatings, and higher solids coatings. Improvements in coating
transfer efficiency decrease the amount that rjust be used to achieve a giver.
film thickness, thereby reducing emissions of VOC to the ambient air. By
using a system with increased transfer efficiency (such as electrostatic
spraying) and lower VOC content coatings, VOC emission reductions can approach
those achieved with control devices.
The data presented in Tables 4.2.2.12-2 and 4.2.2.12-3 are representative
of values which might be obtained from existing plants with similar rperating
characteristics. Each plant has its own combination of coating formulations,
application equipment and operating parameters. It is recommended tlu.t,
whenever possible, plant specific valuer, be obtained for all variables when
calculating emission estimates.
Another method that also may be used to estimate emissions for metal
furniture coating operations involves a material balance approach. Ey assuming
that all VOC in the coatings applied are evaporated at the plant site, an
estimate of emissions can be calculated using only the coating formulation and
data on the total quantity of coatings used in a given time period. The
percentage of VOC solvent in the coating, multiplied by the quantity of coatings
used yields the total emissions. This method of emissions estimation avoids
the requirement to use variables such as coating thickness and transfer
efficiency, which are often difficult to define precisely.
5/83 Evaporation Loss Sources 4.2.?.12-3
-------
TABLE 4.2.2.12-1. COATING METHOD TRANSFER EFFICIENCIES
Application Methods Transfer Efficiency
(Te)
Air atonized spray 0.25
Airless spray 0.25
Manual electrostatic spray 0.60
Nonrelational automatic
electrostatic spray
Rotating head electrostatic
spray (manual and automatic)
Dip coat and flow coat 0.90
Electrodeposition 0.95
TABLJ. 4.2.2.12-2. OPERATING PARAMETERS FOR COATING OPERATIONS
Plant Oj/?rating Number ot line- Line speed Surface area Liters of ,
size schedule (m/'nin) co?ted/yr coating used
(hr/yr) (m2) '
S>,,all
Medium
Large
2,000
2,000
2,000
1
(1 spr& .' f ooth)
2
(3 booths/linej
10
(2 booths/line)
2.5 45,000 5
2.4 780,000 87
4.6 4,000,000 446
,000
,100
.600
Line speed is not used to caicuJate emissions, only to characterize
plant operations.
Using 35 volume % solids coating, applied by electrostatic spray at
65 % transfer efficiency.
4.2.2.12-4 EMISS10F FACTORS 5/83
-------
TABLE a.2.2. 12-3. EMISSION FACTORS
FOR "OC FROM SURFACE COATING OPERATIONS
a,b
Plant Size and Contrt 1 Techniques
Small
Uncontrolled emission!.
65 volume \ high solids coating
Waterb' me coatiiig
Medium
Uncontrolled emission*
65 volume % hi; h solids coating
Waterborne coa:ing
Large
Uncontrolled emissions
65 volume % hifch solids coating
Waterborne coating
voc
kg/ID2 coated
.064
.019
.OK
.064
.019
.012
.064
.019
.012
Erais sions
kg/year
2,875
835
s:>o
49,815
14,445
3,970
255,450
74,080
46,000
kg/hour
1.^4
.42
26
24.90
7.27.
4 48
127.74
37.04
23.00
Calculated using the parameters given in Table 4.2.2.12-2 and the
following equation. Values have been rounded off.
E =
0.0254 A T V D
S Te
where E = Mass of VOC emitted per hour (kg)
A - Surface area coated per hour (m*)
T = Dry film thickness of coating applied l.mi'.s)
V = VOC content of coating; including dilutir-n
solvents addfd at the plant (fraction by volume)
D = VOC density (assumed to be 0.88 kg/1)
S = Solids content of coating (fraction by volume)
Te - Transfer efficiency (fraction)
The constaat 0.0254 converts che volume of dry filn, applied per m2
to liters.
Example; The VOC emission from a medium size plant, applying 35
volume % solids coatings and the parameters given in
Table 4 .2.2.12-'!.
v , , 1Iftr..
Kilograms "' VOC/hr =
0.0254(390m2/hr)(l
-
(0. 65) (0.88 kg/1)
- -
(035)(0.65)
=24.9 kilograms of VOC per hour
'Nominal values of T, V, S and Te:
T = i oil (for all cases)
V = 0.65 (uncontrolled), 0.35 (C5 volume % solids), 0.117 (waterborne)
S = 0.35 (uncontrolled, 0.65 (65 volume % solids), 0.35 (waterborne)
Te = 0.65 (for all cases)
5/83
Evaporation Loss Sources
4.2.2.12-5
-------
Refereace for Section 4.2.2.12
1. Surface Coating of Metal Furniture - BackgroundInformation for Proposed
Standards. EPA-450/3-30-007a, U. S. Environmental Protection Agency, Research
Triangle Park, NC, September 1980.
4.2.2.12-6 EMISSION FACTORS 5/83
-------
4.3 STORAGE OF ORGANIC LIQUIDS
4.3.1 Process Description
Storage vessels containing organic lnjuids can be found in many
industries, including (1) petroleum producing and refining, (2) petro-
chemical and chemical manufacturing, (3) bulk storage and transfer
operations, and (4) other industries consuniriR or producing organic liquids
Orgam«. liquids in the retroleum industry, usually called petroleum liquids,
generally are mixtures of hydrocarbons having dissimilar true vapor pressures
(for example, gasoline and crude oil). OrganiL liquids in the chemical
industry, usually called volatile organic liquids, are composed of pure
chemicals or mixtures of chemicals with similar true vapor pressures (for
, benzene or •'< mixture of \sopropyl and butyl alcohols).
Five basic Lank designs are used for organic liquid storage vessels,
fixed roof, external floating roof, internal floating roof, variable vapor
space, and pressure (low and high).
Fixed Roof Tanks - A typical fixed root tank is shown ir. Figure 4.3-1.
This type of tank consists of a cylindrical steel shell with a permanently
affixed root, which may vary in design from cone or do.ne shaped to flat.
Faxed roof tanks are commonly equipped with a pressure/vacuum vent
that allows them to operate at a slight internal pressure or vacuum to
prevent tlie release cf vapors during very small changes in temperature,
pressure or liquid level. Of current tank designs, the fixed roof tank is
the lear.t expensive to construct and is generally considered the minimum
accept?ble equipment tor storage of organic liquids.
Gang* Batoh
MonlMl*
Maahola
Nozzli (For
•ubMrged fill
or drainage)
9/85
Figure 4.3-1. Typical fixed root tank.1
Evaporation Lo;:s Sources
-------
External Floating Roof Tanks - A typical external floating roof tank is
shown in Figure 4.3-2. This type of tank consists of a cylindrical steel
shell equipped with a roof which i'loats on the surface of the stored liquid,
rising and falling with the liquid level. The liquid surface is conpletely
covered by the floating roof, except at the small annular space between the
roof and the tank wall. A seal (or seal system) attached to the roof
contacts the tank wall (with small gaps, in some cases) and covers the
annular sp-ice. Pue seal slides against the tank wall as the roof is raised
or lowered. The purpose cf the floating roof and the seal (or seal system)
is to reduce the; i'-vaporation loss of the stored liquid.
Internal Floating Hoof Tanks - An internal floating roof tank has both a
permanent fixed roof and a deck inside. The deck rises and falls with the
liquid level and either floats directly on the liquid surface (contact
deck) or rests on pontoons several inches above the liquid surface (non-
contact deck). The t^rms "deck" and "floating roof" can be used
interchangeably in reference to the structure floating on the liquid inside
the tank. There are two basic types of internal floating roof tanks, tanks
in which the fixed roof is supported by vertical columns within the tank,
and tanks with a self-sjpporting fixed roof and no internal support columns.
Fixed roof tanks that have been retrofitted to employ a floating deck are
typically of the first type, while external floating roof tanks typically
have a self-supporting roof when converted to an internal floating roof
tank. Tanks initially constructed with both a fixed roof and a floating
deck may be of either type.
The deck serves to restrict evaporation of the organic liquid stock.
Evaporation losses from decks may come from deck fittings, nonwelded deck
scams, and the annular space between the deck and tank wall. Typical
contact deck and noncor.tact deck internal floating roof tanks are shown in
Figure 4.3-2. Fxternal floating roof Lank.1
EMISSION FA' TORS
9/85
-------
Figure 4.3-3. Contact decks can be aluminum sandwich panels with a honey-
comb aluminum cc.re floating in contact with the liquid, or pan steel decks
floating in contact with the liquid, with or without pontoons. Typical
noncontact decks have an aluminum deck or an aluuii r.j.n grid framework
supported above the liquid surface by tubular alurnnum pontoons or other
bouyant structures. Both types of deck incorporate rim seals, which slide
against the tank wall as the deck moves up and down. In addition, these
tanks are freely vented by circulation vents at the top of the f.".ed roof.
The vents minimize the possibility of organic vapor accumulation in con-
centrations approaching the faramable range. An internal floating root
tank not freely vested is considered a pressure tank.
Pressure Tanks - There are two classes of pressure tanks in general use,
low pressure (2.5 to 15 psig) and high pressure (higher than 15 psig).
Pressure tanks generally are used for storage of organic liquids and gases
with high vapor pressures and are found in many sizes and shapes, depending
on the operating pressure of the; tank. Pressure tanks are .-quipped with a
pressure/vacuum vent that, is set to prevent venting loss from boiling an<\
breathing loss from daily temperature or barometric pressure changes. High
pressure storage tanks can be operated so that virtually no evaporative or
working losses occur. In low pressure tanks, working losses can occur with
atmospheric venting of the tank during filling operations.
Variable Vapor Space Tanks - Variable vapor space tanks are equipped vith
expandable vapor reservoirs to accomodate vapor volume fluctuations attribut-
able to temperature and barometric pressure changes. Although variable
vapor space tanks are sometimes used independently, they are normally
connected to the vapor spaces of one or more fixed roof tanks. i'he two
most common types of variable Vripor space tanks are lifter roof tanks and
flexible diaphragm tanks.
Lifter roof tanks have a telescoping roof that fits loosely around the
outside of the main tank wall. The space between the roof and the wall is
closed by either . we', seal, which is a trough filled with liquid, or a dry
seal, which uses a flexible coated fabric.
Flexible diaphragm tanks use flexible membranes to provide expandable
volume. They may be »7ther separate gasholder units or inf^jral units
mounted atop fixed roof tank",.
4.3.2 Emissions And Controls
Emissio0 sources from organic liquids in storage depend upon the tank
type. Fixed roof tank emission sources are Jreathing loss and v.orkirg
Irss. External or internal floating roof tank emission sources are standing
storage loss and withdrawal loss. Standing storage IOFS includes rim seal
loss, deck fitting loss ind deck seam loss. Pressure tanks and variable
vapor space tanks are also emir;r.ion sources.
Fixed Roof Tanks - Two significant t/pes of emissions from f;xed roof tanks
are breathing loss and working IOSF. breathing loss ^ •; the expulsion of
vapor from a tank through vapor expansion and contract1on, which are the
results nf changes in temperature and barometric pressure. This loss
occurs without any liquid level ciiange in the tank.
9/85 Evaporation loss Sources 4.3-3
-------
C*ot*r Vat
Tank Support Celua
with Colwi VmU
Contact Deck Type
VMC
KlM
Fooeoooa
V
'- l«nk Support CnlvaM
with CaluK, H«H
Vapor S(j«c«
NonconlacL Ceck Type
4.3-4
Figure 4.3-^. InLorml floating roof tanks.1
EMISSION FACTORS
9/85
-------
The combined loss from filling and emptying is caJled working loss.
Filling loss comes with an increase of the liquid level in the tank, when
the pressure insiiie the tank exceeds the relief pressure and vapors are
expelled from the tank. Emptying loss occurs when air drawn into the tank
during liquid removal becomes saturated with organic vapor and expands,
thus exceeding the capacity of the vapor space.
The following equations, provided to estimate emissions, are applicable
to tanks with vertical cylindrical shells and fixed roofs. These tanks
must be substantially liquid and vapo. tight ind must operate approximately
at atmospheric pressure. Fixed roof tank breathing losses can be estimated
from2;
/
-2MV(
V
= 2.26 x 10-2M -l-73H°-51AT°-soFCK (1)
where:
Ln = fixed roof breathing loss (Ib/yr)
a
M.. = molecular weight of vapor in storage tank (Ib/lb mole), see
Note 1
P. = average atmospheric pressure at tank location (psia)
P = true vapor pressure at bulk liquid conditions (psia), see Note 2
D = tank diameter (ft)
H = average vapor space height, including ro^f volume correction
(ft), bee Not.' 3
AT = average ambient diurnal temperature change (°F)
Fp = paint factor (dimensionl(?r,s) , see Table 4.3-1
C = adjustment factor for small diameter tanks (dimensionless) , see
Figure 4.3-4
K_ = product factor (dimensionless), see Note t»
Notes: (l) The molecular weight of the vapor, 11.,, can be determined by
Table 4.3-2 for selected petroleum liquids and volatile
organic liquids or by analysis of vapoi samples. Where
mixtures of organic liquids are stored in a tank, My can b»
efti-'mated from the liquid composition. A:, an example oi the
latter calculation, consider a liquid known to be composed
oi components A and B with mole fractions in the liquid X
and X, , respectively. Given the vapor pressures of the pu
pure
9/85 Evaporation Loss Sources 4.3-5
-------
TABLE 4.3-1. PAINT F/^TORS FOR FIXED ROOF TANKS'
Tank color
Paint far-tors (F_)
Paint condition
Roof
Shell
Good
Reference 2.
Estimated from the ratios of the seven preceding paint factors.
Poor
White
Alum in am (specular)
White
Aluminum (specular)
WhJ te
Aluminum (diffus^)
White
Light gray
Medium gray
White
White
Alumimi.T (specular)
A 1 urn i. mm (specular)
Aluminum (diffuse)
Aluminum (diffuse)
Gray
Light gray
Medium gray
1
1
1
1
1
i
1
1
1
.00
.04
.16
.20
.30
.3
-------
VD
00
TABLE
PHYSICAL PROPERTIES OF TYPICAL ORLANiL LIQUIDS
•c
o
C/3
O
C
"1
n
Oman ic 1 1 qui.1
PrI i iileum I. icjuids
G.->;^linp Wf> li
C..is.-)lin. RVP 10
Cast) lint- RVP 1
Prude 01 1 RVP 5
Jfl IMtllltl!,l (JP-lt)
Oi st i 1 Kite fuel rnj ?
Restilu^ I oil no . 6
Volatile Organic Liquids
Acetone
Ac ry loni t r i le
B*'ii?.eiie
Car bun drsulfide
laihon Lelrac'il'.oridr
Thlorofora
Cyr I oiir-A..r..'
1 ,^-Oirhlnroethane
El hy taret alt>
>.lhyl alrohul
'sttpropyl alroho1.
Met hy ! A! rohol
Mrthylrne iMoride
Nechylethy! ketone
Lliai rylatp
Vj|)ur
molecular
vei Rht
p 60°F
62
66
68
50
PC
130
no
190
5fl
b?
71!
76
119
84
01
88
46
( A
32
85
"?*>
ICO
133
I3i
92
86
Condrnserf
Product vapor
density (d), density (w), ^ v% fj(.
Ih/gal Ib/gj) - *
P 60°F
5.6
56
5.6
7.1
6.4
7.0
7,1
7.9
6.6
6.8
l.it
10.6
13 . 4
IV. S
£.5
!'J.3
7.6
6.6
f . .'.
6.C
11. 1
6.7
7.9
11.2
12.3
7.3
7.8
fa 60°F
it
5
5
d
5
6
6
6
C
6
7
10
13
12
ft
10
7
6
6
6
! i
b
7
11
12
7
7
.9
.1
.2
.5
•*
.1
.1
4
.6
a
4
6
.4
5
5
5
.6
.6
.6
.6
i
7
V
.2
3
3
.8
40°F
4.7
,.<•
2.3
1.8
0.8
O.U04I
0.0031
0.00002
1.7
0.8
0.6
3.0
0.8
1.5
0.7
0.6
0.6
0.2
0.2
0. 7
3.1
0.7
O.I
0.9
0.5
•\ 2
0.7
SO'K
5.7
4.2
2.9
2.3
1 0
0 . 0060
0.0l>4i
0.00001
22
i .0
0.9
3 9
1. 1
1.9
0.9
0.8
O.B
0.4
0.3
10
4.3
0.9
u.i.
1.2
0.7
0.2
1.0
60'f
6.1
">.2
3.5
2.8
1. 1
0.0085
0.0074
0 . 00004
2.9
1.4
1.2
48
I.H
2.5
1.2
1.0
1. 1
0.6
06
1.4
5.4
12
0.1
1.6
O.o
0.1
1.3
niessuie i n psia at:
7VF
8.3
6. 3
4.3
3.4
1.6
0.011
0.0090
0.00006
3.7
1.8
1.5
60
1.8
3.2
1.6
1.4
1 5
0.9
0.7
2.0
68
1 .5
0.6
2.J
1.2
0.4
'•'
8C"r
9.9
7 4
:j. 2
40
1.9
0 015
0.012
0.00009
4.7
2-4
2.0
7.4
2.3
4. 1
21
1 . 7
1.9
1.2
0.9
2.6
8.7
>.. 1
OR
^.o
1.5
O.t
7.3
90
11
8
6
U
2
0
0
0
5
3
2
9
3
•,
1
2
'I
1
1
3
10
2
1
3
2
0
3
K
t
.8
.2
.8
4
.021
.016
.00013
.9
. 1
.6
2
.0
.2
.6
.2
5
.7
•,
.5
. "J
.7
. I
.3
.0
h
1
IOOT
13-8
10 5
7.4
1. 7
2.7
0.029
0.022
0.00019
7.3
4.0
3.3
1 " .2
3.8
6.3
3.2
2.8
3.2
23
1 fi
4.rj
133
J. i
i.4
4 7
2.1)
1 .0
4.0
1 ,1 ,1-Trirhloropthane
Tri chlorrethy \?n?
Tol uene
Viny lacetate
j"Rpt«-r«-nr«s 3-4.
fnr x »ore comprehensive listing of volatile organic liquids, .see Reference 3.
'RVP - Reid vapor pressurf in psia.
-------
components, ? and P. , and the molecular weights of the pure
components, M3 and M. , M,F is calculated:
d D V
(P X \
-*r)
where: P , by P'-oult's law, is:
? = P X +
r A
(2) True vapor pressures for organic liquid-j can be determined
from Figures 4.J-5 or 4.3-6, or Table A. 3-2. In order tc
I'se Figures 4.3-5 or 4.3-6, the stored liquid tf-mperature, T_ ,
must be Jeterrairied in degrees Fahrenheit. T i:» deter-
mined from Table 4.3-3, given the average annual ambient
temperature, T» , in degrees Fahrenheit. True v.ipor pressure
is tL.' equilibrium partial pressure exerted by ; volatile
organic l.quid, as defined by ASTM-D-2879 or as obtaired
from standard reference texts. Reid vapor pressure is the
absolute vapor pressure of volatile crude oil and volatile
nonviscous, petroleum liquids, except liquified petroleum
gases, as determined by ASTM-D-323.
(3) The vapor space in a cone roof is equal i.n volume t.o a
cylinder, which has the samr base diameter as the cone and is
one third the height of the cone If information is not
available, assume H equals one half tank height.
(4) For crude oil, K_ - 0.65. Fcr all other organic liquids,
KC = 1.0.
Fixed rcof tank working losses can be estimated from1:
L,. = 2.40 x 10-5 M..PVNK.K- (2)
W V II !•
where :
L, - fixed roof working loss fib/year)
M, = rrolprLlar weight of vapor in storage tank f/b/lb mole), see Note 1
to
P- = true vapor pressure at bulk liquid temperature fpsiaj, see Note 2
to L q u a M o r. 1
V = tank capacity (gal,)
S - number of turnovers per ye^ar f d imensi or: 1 ess )
,. _ TotaJ '.!'•,r_ _
T^r.k capacity, V
K'ljSSION fACTOHS
-------
1
!
i
•
7
•
II
14
1
1
I
r— 2
— ]
_ 4
— 8
1*0
130
3
HO —g
-3
•a
100 —5
3
3 5
» —5 b.-
-IS
"3 i
30 —5 N
•f I
——. gj
so _J fc
4.3-5, True vapor pressure (P) of -rude oils (2-15 psi RVP).1
9/85
Bvaporation Loss Sources
4.3-9
-------
020
— 030
— 040
— a so
— 060
r— 070
^- CM
~ OM
— i ao
120
10C;-
90
•— 1 50
Q. -
- 200
— 250
~- 300
3 r
35C
400
80
70-^ 5
_
60
_ i
-
500^
60(j
/;•} 20
- K
- O
SOI Rl F
700
~- 8.00
S- 900
— 100
•—11.0
tl-,70
r_. 130
— 14C
r- ISO
h- 160
— 170
t_ 18.0
^— 19.0
jE- 20.0
t~ 21 0
t- 220
^ 23.0
— 240
.<-
S SLOPE OF THE ASTM DISTILLATION
CUBVE AT 10 PtflCSNT EVAPCNATFD
DEC F AT lb PIKCtNT MINUS DECi F AT 5 PERCENT
~ 10
IN THE ABSENCE Of DISTILLATION DATA
THE FOLLOWING AVERAGE VALUf. OF 5 VAV BE USED.
MOTOR GASOLINE
AVIATION GASOLIN€
LIGHT NAPHTHA lb- 14 LB RVPI
NAPHTHA (2-8 LB HVP'
20-;
35
2 *>
lur K\ P • |l< unj» per v^jjrc in. i jivili
i JfJ*n (rum ihe djlj uf the Njlumjl BJICJJ i I NuniJjtJ,
(>. True vapor prusure (P) of refined petroleum liqiuds
iJke gasoline and napththas (J-2.0 psi
,nj f „•
4.3-10
EMISSION FACTORS
9/85
-------
K« =
C
do te:
turnover factor (dimensionless), see Figure 4.3-7
product factor (dimensionless), sec Note 1
(1) For crude oil, Kr = 0.84. For all other organic liquids,
KC = i.o.
TABLE 4.3-3. AVERAGE STORAGE TEMPERATURE (T )
Afl A FUNCTION OF TANK PAINT COLOR"
Tank color
Average storjge temperature,
TS
White
Aluminum
Gray
Black
.Reference 5.
T. is the average annual ambient temperature in
degrees Fahrenheit.
t 3.5
T. + 5.0
A
1.0
S 0.8
0.6
0.4
0.2
0 100 200 300 400
TURNOVERS PER YEAH - ANNUAL THROUGHPUT
TURNOVERS PER YEAR - TANK CA?ACITY
Rot*: For 36 turnovers per yetr or ICES, K« - 1.0
Figure 4.3-7. Turnover factor (K,.) for fixed root" t^nks.
9/fl5 Evaporation Loss Sources 4.3-11
-------
Several methods are used to control emissions from lixe.1 root tanks.
Emissions i rom fixed root Lanks can !e controlled by the intrt j J 1 j t ion of an
internal floating roof and reals to minimize evapc ration of the product
being stored. The control efliciency of this, method ranges 1 . OH, 60 t o
4)9 percent, depending on the type of roof and seals installed and on the
ly-je of organic liquid stored.
"ihe vapor recovery system collects emissions from storage vcsse'ls ,ind
converts tl'.em Lo liquid product. Several vapor recovery procedures in.iy in;
uicd, i:icii.diug vap..r/l i quid absorption, vapor compression, vapor cooling,
vapor''sol 10 adsorption, or a combination of these. The overall control
efficiencies of vapor recovery systems arr as hjgh js 90 to Vti pfi >. vat ,
depending on the wctlu.d usod, the desig.t c-1 rlie unit., the composition ct
vapors recovered, and the mechanical condition of the system.
Another method of omission control on fixed rocf tanks is thermal
oxidation. In a typical thermal oxidation system, the air/vapor mixture is
injected through a burner manil Id into the combustion area of an incin-
erator. Control efficiencies for this system can rarge from 96 to
99 percent.
External And Tti'.ernal Floating Roof Tanks - Total emissions from floating
roof tankt, are the sum of standing storage losses and withdrawal losses.
Standing storage loss from internal floating roof tanks includes i im seal,
deck fitting, and deck seam losses. Standing stoiage loss from external
floating roof tanks, as discussed here, includes only rim seal lops, since
deck fitting loss equations have not been developed. There is no deck seam
loss, because the decks have welded sections.
Standing storage loss from external floating rcof ta.ks, the mijor
element of evapurativn loss, res-ults trom wind induced mechanisms ,'is air
flows across the top "f an external floating roof tank. These mechanisms
may vary, depending 'i;>on the type of reals used to close the annular vapor
spare between the floating roof and the L jiik wall. Standii.g storugi.- emis-
sions from external floating rcol tanks i.-re controlled by or.f> ov two separate
srals. The firs:t%seai is railed the primary seal, and the other, mounted
above the primaiy seai , is called the secondary seal. Tnere arc throe basic
types of primary seals used on external floating roofs, me'han-cal (metallic
shoe), rcsilieit (nonrnctal lie) , and flexible wiper. The r.silient «e;«i ..in
be Liounti.'d to eliminate the vapor -.pace between the se.il and liquid snrt.ice
',li«juid mounted), rr t.o allow a vapor space between the seal and iiqu • fi
surface (vapor nounced). A primary seal serves as a v?por conservaMon
device dy clo'^in^, the annular space between th^ e'lge ol t ho floating roof
anrl the tank wall. Some primary seals are protected b«f 3 metallic we.'ilhiT
shield. Additional evaporative lops may be controlled by a sec^no.iry i>-'cil.
Secondary seals ran he either flexible wiper seals or resilient filled
seals. Two configurations of secondary seal are- currently f
primary seals, resiliert toam filled seals and wipers. Siini.'di i-i design
4.3-12 LMJSSION FACTORS
-------
J. Liquid mounted seal with
we.ither shield.
b. Elastomeric wiper seal.
r. ^/apor mounted seal with
ri:n mounted secoiuJary sf;,ii.
d. Metallic sh)f st-al with shot-
mounted secof;dary seal.
. j-ft. I'riiti.ny ;il)it -j icjuddry KC/II k on f i gur,/ r i oil.'; . '
l>'.ii)or,i t i ori Loss Sources ^.'3-13
-------
to those in external floating roof tanks, these seals close th.i annular
vapor space betwee i the edge of the floating roof and the tank wall.
Secondary seais are not commonly used with internal floating roof tanks.
Deck fitting loss emissions from internal float Lag roof tanks result
from penetrations in the roof by deck fittings, fi:
-------
7. Vacuum Breaker. A vacuum breaker equalizes the pressure of the
vapor space across the deck as the deck is either being landed on or floated
off its le^s. The vacuum breaker consists of a well with a cover. Attached
to the undr.rside of the cover is a guided leg of such ler.gt1) that it contacts
the tank bottom as the internal floating deck approaches. When 01 contact
with the tank bottom, the guided lex mechanically ''.pens the breaker by
lifting the cover oif the veil; otherwise, the co.-er closes the veil. The
closure may be gasketed or ungaskeied. Because (.he purpose of the vacuum
breaker is to allow the free exchange of air and/or vapor, the well does
not extend appreciably below the deck.
The decks of internal floating roofs typically are rrade by joining
several sections of deck material, resulting in seams in the deck. To the
extent that these seams are not completely vapor tight, they become a
source of emissions. It should be noted that external floating louf Ldnks
and welded internal floating roofs do not have deck seam losses.
Withdrawal loss is another source of emissions from floating roof
tanks. This loss is the vaporization of liquid that clings to vhe tank
wall and is exposed to the atmosphere when a floating roof ij, lowered by
withdrawal of liquid. There is als^ clingage of liquid to columns in
intevnaJ fJoating roof tanks which hawj a column supported fixed roof.
Total Losses FromFloating Roof Tanks - Total floating roof tank emissions
aye the sum of rim seal, withdrawal, deck fitting, and deck seam losses.
It should be noted that external floating roof trnks and welded internal
floating rcofs do not have deck seam losses. Also, there are no procedures
for estimating emissions from external floating roof tank dec!» fitting?.
The equations provided in t'lis Section are applicable only to freely vented
internal floating roof tanks or external floating roof ta'iks. The equzitions
are not intended to be used in the following applications: to estimate
losses from closed internal floating roof tanks (tanks vented only through
a pressure-vacuum vent); to estimate losses i rom uristabilized or boiling
stocks or from mixtures of hydrocarbons or petrochemicals for which thr
vapor pressure is not known or cannot ),p readily predicted; or ;.o estimate
losses from tanks in which the materials used in Lhr seal system :ind/or
deck construction are either deteriorated or significantly permeated by the
storel liquid.6 Total losses may be written as:
1T - LR + LW * LF - LD
where:
L_ = total loss (In/yi-J
LD = rim seal loss (see Equation 4)
K
Ly = withdraw-.! loss (see liquation 5)
L.,. = deck fitting loss (see Equation 6)
L = deck sejm loss (s,>-i- Equation 7)
9/S5 Evaporation LOG- Sources 4.3-15
-------
RJTI Seal Loss - Rim seal loss from floating roof tanks cm be estiaated
by the following equation5-6:
LR = KgVVDM^ (4)
where:
Lp = rlfii seal loss (Ib/yr)
KS = seal factor (lb-mole/(ft (ui/hr)" yr)), see Table 4.3-4
V = average wind speed at tank site (rai/hr), see Note 1
ti = seal related wind speed exponent (dimensior.less), see Table 4.3-4
p* = vapor pressure function (dimensionless), see Note 2
_P
*** PA
whe re:
F = true vapor pressure at average actual liquid storage
tenperature (psia), see Note 2 to Equation 1
PA = average atmospheric pressure at ^ank location (pcia)
D = tank diameter (ft)
MV = average vapor molecular weight (Ib/lb-raole), see Note 1 to
Equation 1
K., = product factor (rtimensior/less), ser Note 3
Notes: (1) If the wind speed at the tank site is not available, wind
&peed data from the nearest local weather station may be
used as an approximation.
(2) P* can be calculated or read directly from Figuis 4.3-9.
(3) For all organic liquids except ciude oil, K. = l.C. For
crude oil, Xr = 0.4.
Withdrawal Loss - The i ithdrawal loss from floating mof storage tanks
can be estimated using Equation 5.5-6
L =
(0.9'«3)QCWL
W D
1 +
•
j
4.3-16 EMISSION FACTORS 9/85
-------
TABLE 4.3-4. SEAL RELATED FACTORS FOR FLOATING ROOF TANKS3
Tank and seal type
Welded Tank
Ks n
Riveted Tank
Ks
External floating roof tanks
Metallic shot* se;jl
Primary seal only 1.2 1.5 1.3 1.5
With shoe mounted secondary seal 0.8 1.2 1.4 1.2
With rim mounted secondary seal n.2 1.0 0.2 1.6
Liquid mounted resilient seal
Primary seal only 1.1 1.0 NAC NA
W'th weather shield 0.8 0.9 NA NA
With rim mounted secondary seal 0.7 0.6 NA NA
Vapor n.ounted resilient seal
Primary seal only 1.2 2.3 NA NA
With weather shield O.'l 2.2 NA NA
With rim mounted secondary seal 0.2 2.6 NA NA
l
Internal floating roof tanks '
Liquid mounted resilient seal
Primary seal only 3.0 0 NA NA
With rim mounter! secondary seal 1.6 0 NA NA
Vapor mounted resilient seal
Primary seal only 6.7 0 NA NA
With rim mounted secondary seal 2.5 0 NA NA
aBased on emissions from tank sea1, systems in reasonably good working
condition, no visible holes, tears, or unusually large gaps between
•lie se'jls and the tank wall. The applicability of K decreases in
cases where the actual gaps exceed the gaps assumed during develop-
,ment of the correlation.
Reference 5.
jNA = Not Applicable.
Reference 6.
elf tank specific information is not available about Lhe secondary
seal on an internal floating rocf tank, then assume only a primary
seal is present.
Evaporation Loss Sources 4.3-17
-------
4 S 6 7 g 9 10 M I! 13
TRUE VAPOR PRESSURE /»"JM)
001
•VOTE Duhcd NIK il!uiiri(e< umpk problem Eoj P • 54 pou:tdt pel xiuarc inch absolute
uoi
4.3-18
Figure ^t.J-9. Vapor pressure function
EMISSION FACTORS
-------
where:
L,, = withdrawal loss (Ib/yr)
Q = throughput. (bbl/year) (tank capacity [bbl] tines annual turnover
rate)
C = shell clingage factor (bbl/1,000 ft2), see Table 4.3-5
WT = average organic liquid density (Ib/gal), see Note 1
D = tank diameter (ft)
Np - nujiibt-r of columns (dimension! ess) , see Note 3
F_ - effective column diameter (ft) [column per^metir (ft)/7i], see
Note 4
Notes: (1) if W. is not known, an average value of 5.6 Ib/gallon can be
assrmed for gasoline. An average value cannot t>e assumed
for crude oil, since densities are highly variable.
U) The constant, 0.943, has dimensions of (1,000 ft3 x gal/bbl2).
(3) For self-supporting fixed roof or an external floating roof
tank:
For colu.Tri supported fixed rouf;
N^ = use tank specific information, jr see Tab'ie 4.3-6.
(4) Use tank specific effective column diameter; or
F_ = 1.1 for 9 inch by / inch builtup columns,
0.7 for 8 inch diameter pipe columns, and
1.0 if column construction details are not
known.
Deck Fitting Loss - Deck fitting loss estimation procedure1: for external
floating roof tan<
-------
TABLE ft. 3-5. AVERAGE CLINGAGE FACTORS (C) (bhl/1,000 ft2)*
c adition
Liquid Light rust Dense rust Guiiite lined
Gasoline 0.0015 0.0075 0.15
Single component 0.0015 0.0075 0.15
stocks
Crude oil 0.0060 0.030 0.60
.Reference 5.
If no specific information is available, th-se values can be asswnet
to repiesent the most coiunon condition of tanks currently in use.
TABLE 4.3-6. TYPICAL NUMBER OF COLUMNS AS A
FUNCTION OF TANK DIAMETER FOR INTERNAL FLOATING
ROOF TANKS WITH COLUMN SUPPORTED FIXED ROOFS3
Tank diameter range Typical number
D (ft) of columns, Nr
0 < D g
85 < D S
100 < D S
1^.0 < D 5
135 < D ^
85
100
120
135
150
1
6
7
8
9
150 < D S 170 16
170 < D S 190 19
190 < D S 220 22
220 < D S 235 31
235 < D ? 270 37
270 < D 3 275 43
275 < D £ 290 49
290 < D < 330 61
330 < D ^ 360 11
360 < D i 400 3i
Reference 1. This table was derived from a survey
of users and manufacturer*,. The actual number cf
colurai.s in a particular t ir'.. may vary greatly with
age, fixc-d roof style, leading specifications,
and manufacturing perogatives. Dita ^'r this table
should not supersede information on actual tanks.
4.3-20 KMISSION FACTORS 9/85
-------
whe re :
L_, — the fitting loss in pounds per year
I_ = total deck fitting loss factor (lb-mol j/yr)
= [(N_ K_ ) + N_ K- 1 f . . .+ (N_ K., )]
Fl Tl F2 TZ Fn Tu
where:
N - number of deck fittings of a particular type
i (i = Q,l,2,...,n) (dimensionsless )
K_, = deck fitting loss factor irr a particular type fitting
i fj = 0,1, 2,..., a) (Ib-moJ.e/yr)
n = total number of diiferent types of fittings
(dimensionless)
P*, M.., Kp = as defined for Equation 4
The value cf F_ may be calculated by using actual tank specific data
for the number of each fitting type (fL, ) and then multiplying by the
fitting loss factor for each fitting (1C ).1 Values of fitting loss factors
and typical number of fittings are presented in Table 4.3-7. Where tank
specific data for the number and kind of deck fittings are unavailable,
then F_ can be approximated according to tank diameter. Figures A. 3-10 and
4.3-11 present F_ plotted against tan!: diameter for column supported fixed
roofs and self-supporting fixed roofs, respectively.
Deck Seam Loss - Deck seam loss applies only ti internal floating roof
tanks with bolted decks. External floating roofs have welded decks and,
therefore, no deck seam loss. Deck seam loss can be estimated by the
following equation:6
whete
L = deck seam losses (Ib/yr)
K- - deck seam loss per unit seam length factor (Ib-mole/ft yr)
= 0,0 for voided deck ind external floating rot f tanks,
0.34 for bolted deck
S_ - deck seam length factor (ft/ft2)
L
_ seam
~ A] T
deck
9/85 Evaporation Loss Sources '..3-21
-------
TABLE 4.3-7. SUMMARY OF INTERNAL FLOATING DECK FITTING LOSS
FACTORS CKF) AND TYPICAL NUMBER OF FITTINGS (Nf)a
iJeck fitting type
Deck
fitting loss
factor, Kp
(Ib-mole/yr)
Typical number
of fittings,
NF
Access hatch
Bolted cover, gasketed 1.6
Unbolted cover, gasketed 11.
Unbolted cover, ungasketed 25
Automatic gauge float well
Bolted cover, gasketed 5.1
Unbolted cover, gasketed 15.
Unbolted cover, ungasketed 28
Column well
builtup column-sliding cover, gasketed 33,
Builtup column-sliding cover, ungasketed 47
Pipe column-flexible fabric sleeve seal 10
Pipe column-sliding cover, gasketed 19
Pipe column-sliding cover, ungasketed 32
Ladder well
Sliding cover, gasketed 56,
Sliding cover, ungasXeted 76
Roof leg or hanger well
Adjustable
Fixed
n raple pipe or well
Slotted pipe-sliding cover, gasketed
Slotted pipe-sliding cover, ungasketed
Sample well-slit fabric seal,
10% open area
7.91
0
44
57K
12b
Stub drain, 1 inch diameter 1.2
Vacuum breaker .
Weighted mechanical actuation, gasketed 0.7
Weighted mechanical actuation, ungasketed 0.9
1
(see Table 4.3-6)
(3 * - * -)
10 600
• 2 c
125
1
Reference 1.
If r.j specific information is available, this value can be assumed to
represent the most common/typical deck fittings currently used.
[jD = tank diameter (ft).
Not used on welded contact internal floating decks.
4.3-22
EMISSION FACTORS
9/85
-------
MOO
•000
MOO
4UO
JSO
3000
2800
2000
1100
1000
900
BOLTED D€CK(8*« NOIB1 " /
, - (00411) 0" + (1.M2ID + 194 i /
X
V
WELOCrtDECK
• - (O.OCtt) 0* + (1.382) D * 134.2
100
150 TO 260
TANK DIAMETER, o m
300
390
400
BASIS: Fittuigi include: (1) acceu hatch, with >ii.faiketed. unboiled cover; (2) buih-un column wellt. witti
ungafketcd. iltduig cover; (J) adjustable d«ck leg.. (4) gauge float well, with ungukeieO unboiled cover, (SI
ladder well, with ungajieicd iliding cover; (6) umpk well, with tin fibhc seal (10 percent open aiea). (7) I •
inch diameter nub dnisu (only on 0ohed deck); and (1) vacuum breaker, with gaskeied weighted mechanical
actuation Thii baiii wu drnved from a mrvty of uien and manufacmitn Other liniiigi may be typically UKd
wiihn particiilar compajMt or or|anitaiiom tc neflect wandardi and/or tpecific«iioni of that group Thii figure
thould not lupcnade information Bated on actual tank data
NOTE: If no ipnrific infornuiion u availaolc. uuime bolted decki *re the ;non corritnon/iyf ' vpe cunenlly in
UK in lanlu with cclurnn-supyorud fixed roofs.
Figure A.3-10. Approximated total deck fitting loss factors (T ) fo^
typical fittings in tanks witn column supported fixed roofs and cither a
bolted deck or a welded deck.6 This figure it to be used only when tank
specific data on the number am! kind of deck littings are unavailable.
9/85
Evaporation Less Sources
4.3-23
-------
4000
3500
3009
2900
2309
1500
1000
500
BOITEU DECK
f, • (0.0221) Of - (0 79) 0 « 106 2
i
~
WtLOfiD DICK (&•• MOW)
f, - (0 0132) 0* » (0.7|i 0 - iOS.2
SO
100
150
200 250
TANK DIAMFITR. D -ft)
3uO
350
400
Finings include: (1) access hatch, with ungasketed. unbolted cover; i2) adjustable cL^ legs; (3) gauge
float H-ll, with jrgasketed, unbolted cover; (4) sample well, with il'i fabn; seal (10 percent open area): ed only
when tank specific data on the rumber and kind of deck fittings are
unavailable.
.3-24
EMISSION FACTORS
9/85
-------
where:
= tota? length cf deck seams (it)
Adeck = area of deck
D, P*, MV, KC = as defined for Equation 4
If the total length of the deck scam is not known, Table 4.3-E CAII Le
used to determine S~. Viiere tan*. specific data concerning width of deck
sheets or size of deck panels are unavailable, a default value fcr SD can
be assigned. A value of 0.20 (ft/ft*/ c*n be assumed to represent the most
common bolted decks currently in u^e.
TABLE 4.3-8. DECK SFAM LENGTH FACTORS (Sfl) FOR TYPICAL
DECK CONSTRUCT10HS FOR INTERNAL FLOATING ROOF TAJIKS3
Typical deck seam
length factor,
Deck construction S_ (ft/ft2)
Continuous sheet construction
5 ft wide 0.20C
6 ft wide 0.17
7 ft wide 0.14
Panel construction
5 x 7.5 ft rectangular 0.33
5 x 12 ft rectangular 0.28
Reference 6. Eerk seam loss applies to bolted decks only.
b 1
Sn = -. where W = sheet width (ft)
° W'
p
If no specilic information is available, these
factors can he assumed to represent the most common bolted
decks currently in use.
Sn = Tu , where W = panel width (ft) and L = panel
U LW length (ft)
Pressne Tan.Ks - Losses occur during wjthdrsval and filling operations i.u
low pressure C2.5 to 15 psig) tanks wtn?n Jt-r-ospheric venting occurs. High
pressure tanks are considered closed ;y;>tpms, with virt-ially no emissions.
Vapor re<-,-,vf!ry systems are often foun.l on low pressure tanks Fugitive
losses aie also associated with pressire tanks and their equipment, but
9/85 Evaporation Less Sources 4.3-25
-------
with proper system maintenance, these losses are considered insignificant.
No appropriate correlations are available to estimate vapor losses frou
pressure tanks.
Variable Vapor Spare Tanks - Variable vapor space filling losses result
when vapor is displaced by liquia during filling operations. Since the
variable vapor space tank has an expandable vapor storage capacity, this
loss is not as large as the filling loss associated with fixed roof tanks.
Loss of vapor occurs only when the lank's vapor storage capacity is
exceeded.
Variable vapor jpace system fill.uig losses can be estimated from:3-'
M..J'
Lv = (2.«0 x 1C-2) ~- ((V,) - (0.25 V2N2)) (8)
where:
L., - variable vapor ipace filling loss (lb/103 gal throughput)
M.. = molecular weight of vapor in storage tank (Ib/lb-mole), see Note 1
to Equation 1
P - true vapor pressure at bulk liquid conditions (psia), see Note 2
to Equation 1
Vi = volume of liquid pumped into sys-.m, throughput (bbl)
V2 = volume expansion capacity of system (bbl), see Note 1
N2 = number of transfers into system (dimensionless), see Note 2
Notes: (1) V2 is the volume expaasior capacity of the variable vapor
space achieved by roof lifting or diaphragm flexing.
(2) N2 is the number of transfers into the system during tre
time period that corresponds to a throughput of Vj.
The accuracy of Equation 8 iz not documented. Special tank operating
conditions may result in actual losses significantly different from the
estimates provided by Equation 8. It should also be noted that, although
nrt developed t~>r use with heavier petrol rum liquids such as kerosenes and
tuel oils, the equation is recommended for use with heavier petroleum
liquids in the absence of better data.
4.3.3 Sample Calculations
Three sample calculations to estimate emission losses are provided,
fixed rcof tank, external floating roof tank, and internal floating roof
4.3-26 EMISSION FACTORS 9/85
-------
tank. Note that the same tank size, tank painting, stored product, and
ambient conditions are employed in each sample calculation. Only the type
of roof varies.
Problem I - Estimate the total loss from a fixed roof tank for 3 months
based on data observed during the months of March, April and May and given
the following information:
Tank description: Fixed roof tank; 100 ft diameter; 40 ft heighc;
tank shell and roof painted specular aluminum
color.
Stored product: Motor gasoline (petroleum liquid); Reid vapor
pressure (RVP), 10 psia; 6.1 Ib/gal liquid
density; no vapor or liquid composition given;
375,000 bbl throughput for the 3 months.
Ambient conditions: 60°F average ambient, temperature for the 3 mouths;
10 mi/hr average wind speed at the taik site for
the 3 months; assume 14.7 psia atmospheric pres-
sure; average maximum daily temperatui 68CF;
average minimum daily temperature, 47°F.
Calculation: Total loss = breathing lose * working less.
(a) Breathing Loss - Calculate using Equa+.ion 1.
where:
LB = 2.26 x 10-2 My [p-Tp-J D1-73H°-£iAT°-50FpCKc (1)
Ln = breathing loss (Ib/yr)
D
My = 66 Ib/lb-raole (from Table 4.3-2 and RT/F 1C gasoline)
TA - 60°F (given)
T = 62.5°F (from Table 4.3-3, for an alurainun, cclor tank in good
condition and T. = 60°F)
A
RVP = 10 ps..a (given)
P. = 14.7 \>3it (assumed)
P = 5.4 psia (from Figure 4.3-6, for 10 psia Reid vapor pressure
gasoline and Tc = 62.5°F)
O
D = 100 ft (given)
h = 20 fi (assumed H - '4 tank height)
9/S5 Fvaporation Loss Sources 4.3-27
-------
AT - 21°F (average daily maximum, 68-'I, minus average daily
Minimum, 47°F) .
Fp - 1.20 (from Table 4.3-1 and given specular aluminum tan*, color)
C = 1.0 (tank diameter is larger than 30 ft)
Kf = 1.0 (value appropriate foi all organic liquids exrept crude oil)
LB (Ib/yr) =
0.68
(2.26 x 10-2)(66)|-- :)•;* . 1 (100)1-73(20)0-r'l(21)°-50(l.?0)(1.0)(l.O) =
Y 5.4 \
'U4.7-5.4 I
75,3^3 lb,'yr
For the 3 months, Lfi = 75^ = 18,831 lb
(b) Working Loss - Calculate using Equation 2.
LW = 2.49 x io-'j MVPVNKNKC (2)
where:
L. = working Loss (.Ib/yr)
My = 66 Ib/lb-mole (from Tab?e ^.3-1 and RVP 10 gasoline)
P = 5.4 psia (calculated for breathing loss above)
V = 2,350,000 gal
where: V (cubic feet) = - — •; —
4
71 = 3.141
D = 100 ft
h = 40 ft
= 314, i(JO cubic ft
V (gal) - (7.48 gal/ft3) V (ft3)
V (gal) -- 7.48 (314,100) = 2,349,468 gal, round to 2,350,000 gal
throughput/yea.-
tank volume
(375,000 bbl)(4)(42 gal/bbl) ,
"2,350,000 gal "
4.3-28 F.MISS'ON FACTORS 9/85
-------
KJJ = 1.0 (fron Figure 4.3-7 and N = 26.8)
K_ = 1.0 (value.- appropriate for all organic liquids except crude oil)
Ly (lb/yr) -
2.40 x 10-5 (66)(5.4)(2.35xl06)(26.8)(l OHl.O) = 538,705 lb/yr
For the 3 months, L^ = ^^?^ = 134,676 )u
4
(c) Total Loss for the 3 months -
S = 4 + S
= 18,831 + 1.^4,676
= 153,507 Ib
Problem II - Estimate the total loss from an extern;*! floating roof tauk
for 3 months based on data observed during the months of March, April
Hay and g.xen the following information:
Tank description:
Stored product
External floating roof tank with a inechapic.il
(metallic) shoe primary seal in good condition;
100 ft diameter; welded tank; shell :nd roof
painted aluminum color.
Motor gasoline (petroleum liquid); Reid vapor
pressure, 10 psij; 6.1 Ib/gal liquid density; no
vapor or liquid composition given; 375,000 bll
throughput ft-r the 3 deaths.
Ambient conditions: 60°F average ambient temperature for the 3 months;
10 ni/hr average wind speed at tank site for the
3 months; assume 14.7 psia atmospheric pressure.
Calculation:
Total loss = rim se<>] loss t withdrawal loss
deck fitting loss + deck seam loss.
(a) Rim Scal_Lpss - Calculate the yearly rim seal loss from Equation 4.
where:
(4)
= rim snal loss (lb/yr)
= 1.2 (from Table 4.3-4, for a welded tank with a mechanical shoe
primary seal; note that external floating rue's have welded decks
only)
9/E5
Evaporation Loss Sources
4.3-29
-------
n - 1.5 (from Table 4.3-v, D, M , and V values, as in Equation 4.
J L« V
LR = (1.2)(10)1-5(0.
- 2S.5.S1 Ib/yr
For the 3 months, LR = '' - 7,138 Ib
('n' "ithdraual Loss - Calculate the withdrawal loss from Equation 5.
L,^ •= (0.943) -~ 1 + ( -^1
where:
L., = withdrawal loss (Ib/yr)
C.3-30 EMISSION FACTORS 9/85
-------
Q = 1.75 x 105 hbl for 3 months = 1.5 x lO6 bbl/yr (given)
C - 0 0015 bbl/1,000 fl2 (from Table 4.3-5, for gasoline in a steel
tank with light rust assumed for tank in good condition as given)
WT -6.1 1 Wgal i Riven)
L
D = 100 it (given)
Np - 0 (value tor external floating root tanks)
F,, - 1.0 (defa/'i vilue when criumn diameter is unknown; however,
there are no columns *n this tank, and an F value is used only
for calculation purposes)
To calculate yearly withdrawal loss, use Equation S.
(0.943KI-5 x 106)(0.0015K6. 1) (0.0) (1.0)
100 lOO"
= 129 lb/yr
To calculate withdrawal loss for 1 months, divide by A.
Fr.r the 3 months, LW = 129/4 32 Ib
(.:; Deck Fitting Loss - As stated, deck fitting loss estimation procedures
for external floating roof tanks jrc not available. The deck fitting
loss for the 3-motith period is unknown and will be assumed to 0.
(d) Tieck Seam Loss - External floating rouf tanks have welded de.cks ;
therefore, there1 are no deck seam losses.
(t.0 Total Losa for the 3 months - Calculate the to»:a] loss using Equation '3.
= LR + Lw , LF + LD (3)
wheie :
L_, = total loss (lb/3 mo)
Lu - 7,138 lb/3 mo
K
L = 32 lb/3 mo
L., = 0 (assumed)
L., = 7, 138 + 32 + 0 + 0
!
= 7,170 lb/3 mo
9/85 E"aporatinn Loss Sources 4.3-31
-------
Problem III - Estimate the total loss for 3 months from an internal
floating roof tank based on data observed during the months of March. A,)ril
and Hay and given the following information:
Tank description: Freely vented internal floating roof tank;
contact deck made of welded 5 ft wide continuous
sheets, with vapor mounted resilient i^al; the
fixed rooi." is supported by 6 pipe colmiirs; tank
shell ?nd roof painted aluminum; 100 it diameter.
Stored product: Motor gasoline (petroleum liquid); Reid vapor
pressure of 10 psia; 6.1 Ib/gal liquid density;
no vapor or liquid composition given; 375,COO bbl
throughput for the 3 months.
Ambient conditions: 60°F average a.-nbient temperature for the 3 months;
10 mi/hr average wind speed at the tank site for
the 3 months; assume 14.7 psia atmospheric
pressure.
Calculation:
Total loss = rim seal loss + withdrawal loss
deck fitting loss + deck .;ea,,i loss.
(a) Rim Seal Loss -• Calculate yearly rim seal loss using Equation 4.
T -- K VnP*nM K
ijt "*• I\ -, w t AJi A ,. J\ —
(4)
where:
LR - rim seal loss (Ib/yr)
KS = 6.7 (from Table 4.3-4; for a welded tank wi'.h a vapor mounted
resilient seal and no secondary seal)
V = 10 mi/hr (given)
a ~ 0 (from Table 4.3-4 for a welded tank with a vapor mounted
resilient seal and no secondary sea])
P* = 0.114 (calculated in Problem II)
D = 100 ft (given)
MV = f>C Ib/ib-rnole (from Table 4.3-v ai.d RVP 10 gasoline)
Xp = 1.0 (value appropriate for all organic liquids except crude oil)
- 6.7(lO)°(0.m)(iOO)(66)(1.0)
= 5,041 Ib/yr
_ 5,041 _
For the 3 montlis, LR = ^T~ = l,2oO Ib
4.3-32
EMISSION FACTORS
o i ot
-------
(b) Withdrawal Loss - Calculate using Equation 5.
*-T /VCI
Ly = CO.943) -^ I 1 + 1-V J I (5)
where:
L, = withdrawal loss (Ib/yr)
Q = 1.5 x 106 bbl/yr (calculated in Problem II)
C = 0.0015 bbl/1,000 ft2 (from Table 4.3-5, light rust)
W. =6.1 Ib/gal (given)
D = ICO ft (given)
Nr = 6 (given)
\.t
F. = 1.0 (defaulr value since column construction details are unknown)
(0.943)(1.5xl06)(0.0015)(6.1)
W ~ 100
= 137 Ib/yr
For the 3 months, Ly - ^~ - 34 lb
(c) Deck Fitting Loss - Calculate using Equation 6,
where:
Lp = deck fitting loss (Ib/yr)
Y~ = 700 l'j-mole/yr (interpreted from Figure 4.3-10, given tank diameter
of 100 ft)
P* = 0.114 (calculated in Problem IIJ
MV = 66 Ib/Jb-mole (from Table 4.3-2 and KVP 10 gasoline)
K = 1.0 (value appropriate for all liquid organics except crude oil)
= 700(0,
= 5,267 lb/vr
Tor the 3 months, L_ = 5'267 = 1,317 lb
* 4
9/Sf. Evaporation Lo6i» Sources 4.3-33
-------
(d/ Deck Seam Loss - Calculate using Equation 7.
T - K <
JD Vu
where:
Lj. = deck seam loss (Ib/yr)
K_ - 0 for welded seam deck, then rore
(e) Total Loss for 3 months - Calculate from Equation 3.
LT s LR + LW + LF + LD
where:
LT = total Joss (Ib/yr)
LR = 1,260 ]b/3 mo
LW = 34 lb/3 mo
LF = .i.jl"1 lb/3 mo
LT = 1,260 + 34 + 1,317 + 0
For the 3 months, L,p = 2,611 Ib
References lor Section 4.3 -
3. VOC Emissions From Volatile Organic Liquid Storage Tanks - Background
InfGrTidtion f c r Proposed Standards, EPA-45073r8l-003a, U. S. Environ-
mental Prot-p»:tion Agency, Research Triangle Park, NC, July 1984..
2. BackgrounJ Docunientat^on for Storage of Organir Liquids, EPA Contract
NoT 68-CT:3"i7'4, TRW Environmental, Inc., Research Triangle Park, NC,
May 198"..
3. Petrochemical Evaporation Loss From Storage Tanks, Bulletin No. 2523,
American Petroleum Institute, New Yrrk, NY, 1969.
4. Henry C. Barnelt, et^ajl^, Properties of Aircraft Fuels, NACA-TN 3276,
Lewis Flight Propulsion Laboratory, Cleveland, OH, August 1956.
5. EvaporationLoss From External Floating Roof Tanks, Second Edition,
Bullr-tin No. '^517, American Petroleum Institute, Washington, U. C. ,
19BO.
4.3-34 EMISSION FACTORS 9/85
-------
6. Evaporation Loss From Internal Floating Roof Tanks, Third Edition,
Bulletin No. 2519, American Petroleum Institute. Washington, D. C.,
1983.
7. Use of Variable Vapor Space Systems To Reduce Evaporation Loss,
Bulletin No. 2520, American Petroleum Institute, New York, NY,
9/85 Evaporation Loss Sources 4.3-35
-------
4.4 TRANSPORTATION AND MARKETING OF PETROLEUM LIQUIDS1"3
4.4.1 General
The transportation and marketing of petroleum liquids Involve many
distinct opeidtlona, each of which represents a potential source ot evapo-
ration loss. Crude oil Is transported from production operations to a
refinery by cankers, bargee, rail tank cars, tank truckt, and pipelines.
Refined petroleum products are conveyed to fuel marketing terminals and
petrochemical Industries bv these sane modes. From the fuel marketing
terminals, rhe fuels are delivered by tank trucks to service stations,
commercial accounts and local bulk storage plants. The final destination
for gasoline is usually a motor vehicle gasoline tank. Similar distri-
bution paths exist for fuel oils and other petroleum products. A general
depiction of these activities in shown in Figure 4.4-1.
4.4.2 Emissions and Controls
Evaporative emissions from the transportation and marketing of
petroleum liquids may be separated, by storage equipment and mode of
transportation used, into four categories:
L. Rail tank cars, tank trucks and marine vessels: Loading, transit
and ballasting losses.
2- Service stations: 3ulk fuel drop losses and underground tank
broathlng lorses.
3. Motor vehicle tanks: Refueling losses.
4. Large storage tanks: Breathing, working tnd standing storage
losses. These are discussed in Section 4.3,
Evaporative and exhaust emissions are also associated with motor
vehicle operation, and these topics are discussed In AP-42, Volume II:
Mobile Sources.
Rail Tank Cars, Tank Trucks and Marine Vessels - Emissions from these
sources are due Lo loading losses, ballasting losses and transit losses.
Loadl.ig Losses - Loading losses are the primary source of evaporative
emissions from rat" tank car, tank truck and marine vessel operations.
Loading losses occur as organic vapors In "empty" cargo tanks are
displaced to the atmosphere by the liquid being loaded Into the tanks.
These vapors are a composite of (1) vapors formed In the empty tank by
evaporation of residual product from previous loads> (2) vapors transferred
to the tank in vapor balance systems as product is being unloaded, and
(3) vapors irensrated In the tank as the new product : s being loaded. The
quantity of evaporative losses from loading operations Is, therefore, a
function of the following parameters.
'}/85 E aporatton Loss Sources 4.4-1
-------
.r-
to
•n
|
*—
f
PRtXWCT
STORAGE
TANKS
COMMERCIAL
ACCOUNTS
STORAGE
TANK;
BULK
PLANT
STORAGE
TANKS
00
AUTOMOBILES
AND
Of HER MOTOR
VEHICLES
Figure 4.4-1. Flowsheet of petroleum production, refining, and distribution systems.
-------
• Physical aud chemical characteristics of the previous cargo.
• Method of unloading the previous cargo.
• Operations to transport the empty carrier to a loading terminal.
• Method of loading the new cargo.
• Physical and chemical characteristics of the new cargo.
The principal methods of cargo carrier loading are Illustrated in
Figures 4.4-2 chrough 4.4-4. Ii, the splash loading method, the fill pipe
dispensing tue cargo Is lowered only partway Int." the cargo tank. Signifi-
cant turbulence and vapor/1 iqvild contact occur during the splash loading
operation, resulting in high levels of vapor generation and loss. If the
turbulence is great enough, liquid droplets will be entrained in the vented
vapors,
A second method of loading Is submerged loading. Two types are the
submerged fill pipe method and thi; Dottora loading method. In the submerged
fill pipe method, the fill pipe extends a'most to the hoT.tom of the cargo
tank. In the bottom loading method, a permanent fill pipe is attached to
the cargo tank bottom. During most of both metbody of submerged loading,
the fill pipe opening is below the liquid surface level. Liquid turbulence
Is controlled significantly during submerged loading, resulting in much
lower vapor generation than encountered during splash loading.
The re:ent loading history of a cargo carrier is just as Important a
factor in loading losses as the method of loading. If the carrier has
carried a nonvolatile Liquid such is fuel oil, or has just been cleaned,
it will contain vapor free air. If It has just carried gasoline and has
not be-?n vented, tne air In the carrier tank will contain volatile organic
vapors, which are expelled during the loading operation along with newly
generated vapors.
Cargo carriers are sometimes designated to transport only one product,
and in such cases are practicing "dedicated service". Dedicated gasolin;
cargo tanks return to a loading terninal containing air fully or partially
saturated with vapor from the previo'is load. Cargo tanks may also be
"switch loaded" with various products, so that a nonvolatile product being
loaded iray expel the vapors remaining from a previous Load of a volatile
pri/duct such as gasoline. Thrse circumstances vary w.'th the type of cargo
tank and u'lth the ownership of the carrier, the petroleum liquids o?lng
transported, geographic locarion, and season of the year.
One control raeisurc for gasoline tank trucks is called "vapor balance
service", in whi^h the cargo tank retrieves the vapors displaced during
product unloading at buJk plants or service station? and transports the
vapors back to the loading terminal. Figure 4.4-5 shows a tank truck In
vapor balance service filling a Hervice station underground tank and taking
on displaced gasoline vapors for return to the terminal. A cargo tank
in vapor balance service normally Is saturated with organic vapors, and the
presence of these vapors ai tl.e start of submerged leading results in
greater loading losses than encountered during nonvapor Balance, or
"normal", service. Vapor balance service Is usually nor practiced with
9/85 Evaporation Loss Sources 4.4-.1
-------
fill PIPE
VAPOR EMISSIONS
HATCH COV^B
Figure 4.4-2, Splash loading method.
VAPOR EMISSIONS
PIPI
HATCH OJVIR
CAAuD TANK
Figure 4.4-3. Submerged fill pipe.
VAPOR VENT
TO RECOVERY
OR ATMOSPHERE
HATCH CLOSED
Figure 4.4-4. Bottom loading.
CARGO TANK
FILL PIPE
4.4-4
EMISSION FACTORS
9/
-------
marine vessels, although some vessels practice emission contvol by means of
vapor transfer within their own cargo tanks during ballasting operations (see
page 4.4-10).
MANIFOLD FOR RETUHNING VAPORS
VAPOR VENT LINE
TRUCKSTORAGE\ I / \
COMPARTMENTS
PRESSURE RELIEF VALVES
UNDERGROUND
STORAGE TANK
Figure 4.4-5i Tank truck unloading into d service station
underground storage tank and practicing "vapor balance"
form or emission control.
Emissions from loading petroli.um liquid can be estimated (with a
probable erroi of t30 percent)4 using the following expression:
LL - 12.46 SPM
(1)
where:
M
P
T
S
Loading loss, lb/103 gal of liquid loaded
Molecular weight of vapors, Lb/lb-mole (see Table 4.3-2)
True vapor pressure of liquid loaded, psla (fiee '
4.3-5 and 4.3-6 and Tabl« 4,3-2)
Temperature of bulk liquid loadod, "k ("F + 460)
A saturation fac:or (see Table 4.4-1)
Evaporation Loss Sources
4.4-5
-------
The saturation factor, S, represents the expelled vapor's fractional approach
to saturation, and It accounts for the variations observed In emission rates
fron Che different unloading and loading methods. Table 4.4-1 lists suggested
saturation factors.
TABLE 4.4-1. SATURATION (S) FACTORS FOR CALCULATING
PETROLEUM LIQUID LOADING LOSSES
Cargo caroler
Mode of operation
S factor
Tan't trucks and
rail tink cars
Marine vessels3
Submerged loading of a clean
cargo tank 0.50
Submerged loading: de( Icat'id
normal service C.60
Submerged loading: dedicated
vapor bal a> ce aervir.e 1.00
Splash loading of a clean
carg tank 1.45
Splash loading: dedicated
noriii£.l serv'ct 1.45
Splash loading: dedicated
vapor balance service l.CG
Submerged load! ig: ships 0.2
Submerged load Tag: barges 0.5
•aFcr products othe'" than gasoline aru' crude oil. Use factors
fror, Table 4.4-2 for marine loading of gasoline. Use Eouatlons
2 anc 3 and Tatle 4.4-3 for marine loading of crude oil.
Emissions from controlled loading operscions can be calculated by multi-
plying the uncontrolled emission rate calculated In Equation 1 by the control
efficiency term:
1 -
eff
'100
Measures to reduco loading cessions include sclectiou of alternate
loadiag methods and application of vipor recovery equipment. The latter
captures organic vapors displaced during loading operations and recovers
4.4-6
EMISSION FACTuRS
9/85
-------
the vapors by t'.ie use of refrigeration, absorption, adsorption and/or com-
pression. The recovered product Is piped back to storage. Vapors can also
be controlled through combustion In a thermal oxidation tuilc, with no
product recovery. Figure 4.4-8 demonstrates the recovery of gasoline vapors
from tank trucks during loading operations at bulk terminals. Control
efficiencies of modern unlta range from 90 to over 99 percent, depending on
the nature of the vaporn and the type of control equipment used.'"*
VAPOR RETURN LINE
'-TVT
S-r-i '
1 ,
l\
' \ \
PRODUCT FROM
LOADING TERMINAL
STORAGE TANK
VAPOM-PREE
AIR VENTED
TO
ATMORPHLHE
VAPOR
HEZCOVEFIYl
UNIT
HliCOVERHD PRODUCT
TO STORAGE
Figure 4.4-6. Tank truck lotidiug with vapor recovery,
Sample Calculat 1on - Loading losses (LL) from a gasoline tank truck in
dedicated va-Dor balance service and practicing vapor recovery would be calcu-
lated as follows, using Equation 1:
Design basis -
Cargo tank volume is 8,000 gallons
Gasoline RVP is 9 pslj
Product temperature is 80°F
Vapor recovery efficiency is 95%
Loading loss equation -
L. =
12.46
SPM A - gf.f_
T \ 100
where: S - Saturation factor (see Table 4.4-1) - 1.00
P » True vapor pressure of gasoline (see Figure 4.3-6) = 6.6 psle
M • Molecular weight of gasoline vapcrs (stc Tabl«i 4.3-2) «• 66
T - Temperature of gasoline = 540°R
eff - Control efficiency - 95%
9/85
Evaporation Loss Sources
4.4-7
-------
12.4-6 (l.QC)(b.6)(bb)
(' - -**)
\ 100 /
L 540
« 0.50 lb/103 gal
Total loading losses are:
(0.50 lb/103 gal)(8.0 x 1C1 gal) - 4.0 Ih
Measurements of gasol i tiu loading losses from stlps and barges have • fd
to the development of emission factors for these specific loading operations.'
These factors are preset 3d in Tanl e 4.4-2 and, for gasoline loading oper-
ations at marine terminals, should be us?d instead of Equation 1.
L\\ addition to Equation 1, which estimates emissions from the loading
of petroleum liquids, Equation 2 has been developed specifically tor esti-
mating :he emissions from th* loading of crude oil into ships arid ocean
barges:
cL » CA + CG (2)
where: CL - Total loading loss, lb/103 gal of crude oil loaded
CA * Arrival emission factor, contributed by vapors in the empty
tank compartment prior to loading, lb/103 gal loaded (ace
Note)
CG » Generated emission factor, contributed by evaporation
during loading, 1b/l03 ga.l loaded
This equation was developed empirically based on test measurements of
several vessel compartments.7 The quantity Cf can be calculated using
Equation 3:
CG - 1.C4 (0.44 P - 0.42) M G (3)
T
where: P = True vapor pressure of loaded crude oil, pala (see
Figure 4.3-5 ai.d Table i».3-2)
M -« M^l-'.cular weight of vapors, ib/lb-moiR (see Table 4.3-2)
j " Vapo- growth factor -= 1.02 (rliraenslonleaa)
T = Temperature ot v.ypora, °R (°F + 460)
Note - Values of «' ^ for various cargo tank conditions are listed In
Table i.4-3.
Emission factors derived trow Equation 3 and Tab.'. e 4.<»-3 represent
total organic compounds. Nonmethavie-none thane volatile organic compound
(VOC) emission factors for crude oil vapois have been found to range from
approximately 55 to 100 weight percen1: of these total organic factors.
When specific vapor composition information 13 not available, the VOC
emission factor can be estimated by taking 85 percent of the total organic
factor.3
4.4-8 EMISSION FACTORS 9/85
-------
TABLE 4.4-2. VOLATILE ORGANIC COMPOUND EMISSION FACTORS FOR
GASOLINE LOADING OPERATIONS AT MARINE TERMINALS8
Vessel
tank
condi t Ion
Unclepied
BaJ 1 jited
Cleaned
Cis-f rted
Anv con-
dition
Ci. -freed
Typical
overall
gltuatlon^
Previous
cargo
Volatile^
Volat lie
Volatile
Volatile
Noiwolat 11 e
Any cargo
Any C' v£^
Shlpu,'
*i/l Iter
transferred
315
205
180
85
a5
c
215
Total orsanlo
ocean barged
lb/101 gal
transfs .Ted
2.6
1.7
1. 5
0.7
0.7
e
1.8
«alialun factors
•g/li ter
large>b
lb/101 gal
transferred transferred
465
d
f
e
n
245
*,U
3.9
d
e
e
e
2.0
-
aK«f«r«nc«« 2, 9. Factor* reprment nonn*thane-nontthan« VOC caliiloai bccauie
••thane and etNina h«v« been found to contrllut* a negligible weight fraction cc
the evaporative enlsalona from gaaollne.
''Dcean barges (tank rumpHrtnent dcpLh abuut ^>0 ftet) exhibit emission levels •,loilai
to cark (lips. Shailov draft bargpa (conpartnenr depth 10 tu 12 feet) exhf'jlt
higher colnslon level],
-Volatile cargoei an choie with » true vapor pr«*i8ur« gr«a:er chin 1.5 pria.
^Barges are not usjaliy bsllasted.
•Unavailable.
'sased on obaer-atlon that 412 of tested ahip ±oaparriscnt« were unclafned. 111
ballaateu, 2'-t cli>an«d, snd 24t gas-fraed. For barges, 76* uere jnrieaned.
TABLE 4.4-3. AVERAGE ARRIVAL EMISSION FACTORS, CA, TOR CRUDE
OIL LOADING EMISSION EQUATION1
Ship/ocean barge
tank condition
Uncl eaneri
Ballasted
Cleaned or
ga-j-f reed
Any condition
Previous
cargo
Volatile^
Volatllt
Volatile
Nonvolatil e
Arrival emission
factor, lb/103 gal
0.86
0.46
0,.33
0.33
aArrlval emission factors (CA) to be added ro generated emission
'zctors calculated in Equation 3 to produce total crude oil
loading loss. Th^se factors represent total organic compounds;
nonL..?t!iane-nonethane VOC emission factors average rbout l"j% lower.
bVolatUe cargoes are those with a true vapot pressure greater
than 1.5 psla.
KvaporaM.on Loss So\ircF:8
4.4-9
-------
Ballasting Losses - Ballasting operations are a major source of
evaporative emissions associated with the unloading of petroleum liquids at
marine terminals. It is common practice to load several cargo tank compart-
ments with sea vater after the cargo has been unloaded. This water, termed
"ballast", Improves the stability of the erpty tanker during the subsequent
voyage. Although ballasting practices vary, individual cargo tanks are
ballasted typically about 80 percent, and the total vessel is ballasted 15 to
40 percent, of capacity. Ballasting emissions occur an va;>or laden air In
the "empty" cargo tank is displaced to the atmosphere by ballast water b'ing
pumped into the tank. Upon arrival at a loading port, the ballast water Is
pumped from the cargo tanks before the new cargo is loaded. The ballasting
of cargo tanks reduces the quantity of vapors returning In the empty tank,
thereby reducing the quantity of vapors emitted during subsequent tanker
loading. Regulations administered by the Li. S. Coast Guard require that, at
marine terminals located in ozone nonattainment areas, large tankers with
crude oil washing systems contain organic vapors from ballasting.' This la
accomplished principally by displacing the vapors during ballasting into a
cargo tank being simultaneously unloaded. Mfcrint vessels in other areas emit
organic vapors directly to the atmosphere.
equation 4 has been developed frorc test data to calculate the ballasting
emissions from crude oil ships and ocean barges7:
LB = 0.31 + 0.20 P + 0.01 PUA (4)
where: Lg • Ballasting emission factor, lb/103 gal of ballast water
P » True vapor pressure of discharged crude oil.
paia (see Figure 4.3-5 and Table 4.3-2)
UA - Arrival cargo true ullage, prior co dockside discharge,
measured from the aeck, feet. The tem "ullagu" refers to
the distance between the cargo surface level and Ihe deck
level
Table 4.4-4 lists average total o-ganic emission factors for ballasting
into uncleaned crude oil cargo compartments. The Tirst category applies to
"full" compeltmenta wherein che crude oil true ullage just prior to cargo
discharge is Lens than 5 feet. The aecone' category applies to lightered, or
short-loaded, compartments (part of cargo previously discharged at original
load a partial till), with an arrival true ullage greater than S feet. It
should '3 remembered uhat these tabulated emission factors are examples
only, based on .^erage conditions, to be used when crude oil vnpor pressure
la unknown. Equation 4 should be vised when infornif.ti.on about crude oil
vapor pressure and cargo compartment condition lu available. Thf sample
calculation illustrates the use of Equation 4.
Sappl.e C°l filiation - Ballasting emissions from a crude oil cargo ship
would be calculated ao Callows, us .rig Equation 4:
Design basis -
Vessel and cargo description:
80,000 dead-weight-ton tanker, cru \e oil capacity 500,000 bar..cls;
20 percent of the cargo capacity Is filled witn ballast water aftej
4.4-10 EMISSION FACTORS 9/85
-------
TABLE 4.4-4. TOTAL ORGANIC EMISSION FACTORS
FOR CRUDE OIL BALLASTING0
Average emission factors
By category
Typical overallb
Compart merit
condition before
cargo discharge
tng/ilter lb/103 gal -ng/licer lb/103 gal
ballast ballast ballast bail.ist
water water wa:ev
Fully load*dc
Lightered or
previously
short-1oadedd
111
171
0.9
129
l.l
aAssure8 crude oil temperature of 60°F and RVP of 5 psia. Nonmethane-
none thane VOC emission factors average about 85% of these total
organic factors.
^Based on observation that 70% of tested compartments had been fully
loaded before ballasting. May not represent average vessel practices,
c Assumed typical arrival ullage of 2 ft.
dAssuaed typical arrival ullage of '^0 f:.
cargo discharge. The crude oil has an RVP of 6 pela and Is discharged at
75'F,
Compartment conditions:
70 percent of the ballast water Is loaded Into compartments that had
been fully loaded to 2 feet ullage, ?nd 30 percent Is loaded into
compartments that had been lightered to 15 fe.^.t ullage, before .arrival
at dockslde.
Ballasting omission equation -
1B - 0.31 -r Q.',C- P -- 0.01 PUA
where:
True vapor pr jssure of
4.6
^ oil (see Figure 4.3-5)
UA - True cargo ullage for the Lull compartments =• 2 fe^t, a"d
true cargo ullage for the lightered conpartrjentJ • 15 feet
LB >- 0.70 [0.31
+ 0.30 [0,31
(0.20)(4,6)
(0.2CK4.6)
(0.01 )(.4.6)( 15)]
- 1.5 lb/10J gal
ToLal ballasting emissions are.:
(1.5 lb/103 gal )(0. 2U)(500,000 bbl)(42 gal/bbl) - G.iOO Ib
Since VUC euilartiona average abou1; 85X of these total organic >:'.
emiaslonn of VOC are about: (0.85)(6,300 Ib) - 5,160 Ib
9/35
Evaporation Loss Sources
4.4-11
-------
Transit Losses - In acJltion to loading and ballasting losses, losses
occur while the cargo Is In transit. Transit losses are similar In many
ways Co breathing losses associated with petroleum storage (see Section A.3).
Experimental tests on ships and barges have Indicated that transit losses
can be calculated using Equation 54:
LT - 0.1 PW (5)
where: Lj = Transit loss from ships and barges, lb/week-103 gal transported
P » True vapor pressure of the transported liquid, peia
(see Figures 4.1-5 and 4.3-6 and Table 4.3-2)
W " Density of the condensed vapors, Ib/gal (see Table 4.3-2)
Emissions from gasoline truck cargo tanks during transit have been studied
by a combination of theoretical and experimental techniques, and typical
emission values are presented in Table A.4-5.10"" Emissions depend on the
extent of venting from the cargo tank during transit, which In turn depends
on the vapor tightness of the tank, the pressure relief valve settings, the
pressure In the tank at the start of the trip, the vapor pressure of the
fuel being transported, and the degree of fuel vapor saturation of the
space In the tank. The emissions are not directly proportional to the time
spent in transit. If the vapor leakage rate of the tank increases, emissions
increase up to a point, and then the rate changes as other determining
factors take over. Truck tanks In dedicated vapor balance service usually
contain saturated vapors, and this leads to lower emission during transit,
because no additional fuel evaporates to raise the pressure in the tank to
cause venting. Table '».4-5 lists "typical" values for transit emissions and
"extreme" values that could occur in the unlikely event that all determining
factors combined to cause maximum emissions.
In the absence of specific inputs fcr Equations 1 through 5, the
typical ivaporative emission factors presented in Tables 4.4-5 and 4.4-6
should bo used. It a'.,~»ild be noted that, although the crude oil used to
calculate the emission values presented In these tables has an RVP of 5,
f~- RVP of crude oils can rair'e from less than 1 up to 10. Similarly, the
gasolines has a range of approximately 7 to 13. In areas where
,,iuj.ng ard transportation sources are major factors affecting air quality,
it la advisable to obtain the necessary parameters and calculate emission
estimates using Equations 1 through 5.
Service Stations - Ai,other major source of evaporative emissions Is the
filling of underground gasolinu storage Lanks at service stations. Gaso-
line is usually delivered to service stations In large (8,000 gallon) tank
trucks or smaller account trucks. Emissions are generated when gasoline
vapors In the underground storage tank are dl&placed to the atmosphere by
the gasoline being lorded into the tank. As with other loading losses, the
quantity of the service station tank filling loss depends on several vari-
ables, including the method and rate of filling, the tank configuration,
and the gasoline temperature, vapor pressure i?nd coraposl Men. Using Equa-
tion (1), an average emission rate for submerged filling Is 880 milligrams
per liter of transferred gasoline, and the rate for splash filling is 1,380
milligrams per liter of transferred gasoline (see Table 4.4-7).s
4.4-12 EMISSION FACTORS 9/85
-------
TABLE 4.4-5 TOTAL ORGANIC EMISSION FACTORS FOR PETROLEUM
LIQUID RAIL TANK CARS AND TANK TRUCKS
Emission lourca
Loading op«ratlonac
Subiiergtd loading -
dallcatsd normal service11
•g/il'er transferred
lb/103 g.l transferred
Sutnaerged 1 facing -
vapor balance service1*
•g/lltar transferred
ib/lO3 gal tranaftrrsd
Splash losdlng -
dtdi cited normal lervlct
•g/Hter trans ftrred
lb/10^ t--J trsnsferred
Splssh losdlng -
vapor balance ssrvic*
•g/llter transferred
lb/103 gal transferred
Transit losses
Loaded wlt>. product
•g/lltar transpoited
typical
ex tre*a
Ib/lcP gal transport r-d
typical
eitresjc
Return vltb vapor
Bg/liter transported
typical
eitreae
Ib/iO^ gal transport ad
typlcaa
evtreae
Jet Dmillate kesidual
Crude naphtha Jet oil oil
Caroline* ollb (JF-4) kerosene No. 2 No. 6
590 240 180 1.9 1.7 0.01
5 2 1.5 0.16 0.014 O.OOJ1
980 400 300 e e e
83 2.5 e e e
1.430 580 430 5 A 0.03
12 5 * 0.04 0.03 0.0003
9BC 400 300 e e e
83 2.5 e s e
0-1.0 t t t i I
0-9.0 f f I t f
0 - 0.01 f f t f f
0-0.08 f f f f f
0 - 13.0 f f f f f
0 - 44.0 f ' f f t
0 - 0.11 f f f f f
0 - 0.37 f • f { f
'Reference 2. Gasoline factors represent emissions of nonnethane-nonethane VOC, finer methane
and ethane ronatltutp n negligible weight fraction of the evaporative ealailoni from gasoline.
The exanple gueollne has an KVP of 10 psla.
bThr example crude oil haa an RVP of 5 pala.
c Load Ing ealsalon factors are calculated ualng Equation 1 tor a dispensed product temperature of
60 '¥.
''Reference 2.
eNot normally used.
f Unavailable.
9/85
Evaporation LOGS Sources
A.4-13
-------
TABLE
TOTAL ORGANIC EMISSION FACTORS FOR PETROLEUM
MARINE VESSEL SOURCES3
£•183.jn aour'e
Gasoline*3
Cruje
ollc
Jet
naphtha
(JP-4)
Jet
u Etistfne
Distillate
oil
No. 2
Nvciduai
oil
No. ft
l.oarll ng nperat ions
Ships/ocean bargea
Kg/liter transferred d
Ib/lO-* gal transferred d
Barges
og/lUer translated d
) b/ICJ g.,i transferred d
Tanker si lasting
•g/liter ballaat water 100
lb/101 K.l ballast water 0.6
Transit
ng/ueek-j1ter transported 320
lb/u«ek-103 gal transported 2.7
73
0.61
120
i.'J
i50
1.3
60
0.50
150
1 ,t
84
0.7
0.63
0.005
0.55
u. oo •>
! .60 1 .40
0.013 0.01?
O.OOA
0.00004
0.01 1
(J.OUU09
O.bO
0.005
0,5
-------
TABLE 4.4-7.
EVAPORATIVE EMISSIONS F10M GASOLINE
SERVICE STATION OPERATIONS
Emission source
EnitiSlon
rag/liter
throughput
rate
lb/103 gal
throughput
Filling underground tank
Submerged filling3
Splash filling3
Balanced submerged fill ing
Underground tank breathing
and emptyIngb
Vehicle refueling operations
Displacement losses
(uncontrolled)
Displacement losses
(controlled)
Spillage
880
1,380
40
120
1,320
132
SO
7.3
11.5
0.3
1.0
11.0
1.1
0.7
aThese factors are calculated using Equation 1 for a gasoline
temperature of 60°F and RVP of 10 psJa.
''Includes any vapor loss bet veer, underground tank and gas pump.
Motor Vehicle P.efueltng - Service station vehicle refueling activity also
produces evaporative emissions. Vehicle refueling emissions come from vapors
displaced from the automobile tank by dispensed gasoline and from spillage.
The quantity of displaced vapors depends on gasoline temperature, auto tank
temperature, gasoline RVP and dispensing rate. It Is estimated thdt the
uncontrolled emissions from vapors displaced during ve.ilcle refueling average
1,320 milligrams per liter of dispensed gasoline.
spillage luss is made up of contributions from preflll and postflll
nozzle drip and from spit-back jnd overflow from the vehicle's fuel tank
filler pipe during filling. The amount of spillage loss can depend on several
variables, including service station business characteristics, ctnk configur-
ation, and operatoi techniques. An average spillage loss is SC milligrams
per liter or dispensed gaeoline.1'
Control methods for vehicle refueling emissions are based on conveying
the vapurs displaced from tho vehicle fuel tank to the underground storage
tank vapor space through the use of n special hose and nozzle, as depicted
in Figure 4.4-7 (termed Stage II vapor control). In "balance" vapor control
systems, the vapors are conveyed by natural pressure differentials established
during refueling. In "vr.cuum assist" systems, the conveyance of vapors* from
uhe auto fuel tank to the underground storage tank is assisted by a vacvutn
pump. Although vapor control systems for vehicle refueling activity ate not
currently In widespread operation at service stations, tests on a few systems
have indicated overall s/sJtem control efficiencies In the ra^e of 88 to 92
percent. *
Evaporation Loss Sources
4.4-15
-------
Figure 4.4-7. Automobile refueling vapor recovery system.
References for Section 4.4
1. C. E. Burkiln anrt R. 1. Honercamp, Revision of T.'aporf.tlve Hydrocarbon
Emission Factors, EPA-450/3-76-039, U, S. Environmental Protection
Agency, Research Triangle Park, NC, August 1976.
2. G. A. LaFlam, S. Osbourn and R. L. Norton, Revision of Tank Truck
Loading Hydrocarbon Emission Factors, Pacific Environmental Services,
Inc., Durham, NC, May 1982.
3. G\ A. LaFlaa, Revision of Marine Vessel Evaporative Emission Factors,
Pacific Environmental Services, Inc., Durham, NC, November 1984.
4. EvHppratlon Loss from Tank Cars, Tank Trucks and Marine Vessels,
Bulletin No. 2514, American Petroleum Institute, Washington, DC, 1959.
5. C. E. Burkltn, et al., A Study of Vapor Control Methods for Gasoline
Marketing Operations." EPA-450/3- 75-046A and -046B, II. S. Environmental
Protection Agency, Research Triangle Park, NC, May 1975.
6. Bulk Gasoline Terninala - Background Information for Promulgated
Standards, EPA-450/3-80-036b, U. S. Environmental Protection Agency,
Research Triangle Park. NC, August 1983.
7. Atmospheric Hydrocarbon Emissions frorj Marine Vessel Transfer 0|>ei.a-
tlons^, Publication 2514A, American Petroleum Institute, Wnshington, DC,
1981.
A.4-16
EMISSION FAL10RS
9/B5
-------
B. C. B. Burklin, et al., BackgioundInformation on Hydrocarbon Eaisaione
fro» Mario* T«rain«l Operations. EPA-450/3-76-038a and -038b. U. S.
Environmental Protection Agency, Research Triangls Park, KC.
Novenb-er 1976.
'• Rule* for the Protection of the Marine Environcuent Relating to Tank
Vessels Carryii7g~0il in Bulk, *5 PR 43705. June 30. 1980.
10. R. A. Nichols, Analytical Calculation of FuelTransit Breathing Loag,
Chevron USA, Inc., San Francisco, CA, March 21, 1977.
11. R. A. Nichols, Tank Truck Leakage Measurement8, Chevron U^A, InCf,
San Francisco, CA,June 7, 1977T
12. Investigation of Passenger Car Refueling Losses;FinalReport,
2nd Year Prograa, APTD-1453, U. S. Envlronnental Protection Agency,
Research Triangle Park, NC, Septenh-r 1972.
9/85 Evaporation Loss Source* U.k-
-------
4.5 CUTBACK ASPHALT, EMULSIFIED ASPHALT AND ASPHALT
CEMENT
4.5.1 General"
Asphalt surfaces und pave me us ate ;• opposed of i o.Tpacled aggregate a id an asphalt binder,
ipjteii.iU arepn, -lured f rum rook quarries as manufactured slum or are ol>> aided from natural gravel or soil
deposit*. M*tal ure refining processes produce artificial aggregate-; a< a byproduct. In a-phall. the
aggregate perform? three functions. It transmit* the load frurn thf suif.'-.ce to the hasp course, lakes the
abrasive weur of traffic, and provides a nonskid surface. The asphalt birder holds the aggregate t.-igethe'.
pn \enling displacement and loss of aggregate and providing a water) rrof cmer for the base
\>phall binders take the for™ of asphalt cement 'the residue of the distillation of crude oils I and liquified
n->phali«. Tube u»ed 'or pavement, asphalt cement, which is semisoi.d, must b* heated prior to mixing with
aggregate. The re lulling hut Dili uphalt concrete- n generally applied in thicknesses of fium two to six
inchr<. Liquified asphalt* are (1) asphalt cutbacks i asphalt cement thinned or "cutback" with volatile
petroleum distillates *uch as rmplha, kerowne. etc < and (2) asphalt en.uUions (nonflammable liquids pro-
dui eil I.'' "mbir.ji.g atphalt ami water with unemuUilv ing agent, su^has soap). Liquified asphalls are used
in lack a:ul ».-«! operations. in priming roadbed* f»r hot mix Hppliration, and for paving oprrutio-ii up to
.•.f\erj| inches thick.
<. 'i;h,uk asphalt* fall into thrrt broad categories: rapid cur? iRC). medium cure (MO. anil $|ON> cure
iSt'1 road "• Is. 5'°, MC and RC cutback*, arc prepared by blendi.-.g at>phalt cement with heavy residual oils,
ki-ri'-eiu >,»r solfenl», or n apt ha and ^dvilin--- «iilvcnt». respec lively. Depending on the viscosity Hr*ired.
ul solvent added generaU) rjngf from 2> to -l.i perc'ent L>> M>liirnf.
r'in.il-'fied asphalt * are of two on sic types. Onr type relics i-r\ water evapo; a' on to cure. The other ivpe
: dl.nnu- cinulsiors1 relie- on ionic bondmi* ul ihr cinnl-Mii and ihf aggregalf suilace. tinuliified ..»;ilult
(an >ul'-'ivitc for iulha( km nlmo»t any application F.niuhifi -d asphalts are gaining in popularity, becouse
iij 'hr rnt-T-f\ and environmental problems a-*i4(K iated *»lh I he u>e of cutback asphalts.
t..V2 Emi8ttionsl-2
The (jiiniar) |iul)nuni» of CLIU -HI fron> a.sphallr and a.-phah puving o|iernion> ur<* volatile <>rgan'i
fdiiipuund:- (VOCl. Of ihe 'lirce i>pes of asphalts, thi major uiur"e «•' \O(! i* cull.ick. Only minor
arr;rnjnt« nf V()f. ar? emitted from emulsified asphalls t«nd •'•'prall tement.
\ Ol cm.ssiiin'. from cutbar-k asphalt.- remit iroin the evaporation ol thf ptrtrolrum .li^nlliile solvenl. or
duui-n;. u- •• to liquify the asphalt < rmenl. Emissions DC- ural boih the joh tile and the mixing filant. \l (lit
job Hie, VOCs i<;r emitted from the equipment used 10 apply the aspnahir product anif irum the road
-urfjcc . \l ih*1 mixing plant. \ OC's are released during niix t'ji and ^locApiling. I'lii: laige>' sunrce nf
Tni- -inn-, however. i~ the rodd «urfiife itself.
K'ir anv given amount of c utback asphalt, lulal emissions ari helie*ed ri) he the same, regarillefji ul
-tiirkpiliiig. iii\ing and applii .ition times. Thr two major variables affecting both Ihe <|U.inti!> of \OC.
t 'rilled and tin1 time >\ er t^liich e minion? oft ur are the u pe :in.; the quantity of pein>lei».i Hi:-tillatr u-"d
as a dilurr.i. \- ar appruximaliMn. lo.ig irrm emi»«inn« frnm ( ulback asphalts can he r«tini;it»*-i L>
as-urr.inii ihat 9o percen! nf the a<-k asphalts, 70 pci< eni f/oin
medium < lire iMt^l rutbufks. jud alxiu! I.T percrn' fiom -Inn i ui i> iS(il asphalts, by v» eight per rent Some
iif ll.e diluent appear to be retained peri! the total diluent los- or«''irs 0,1 the fir»t ijav aitfi
"79 E\ a jKji-ation Loss Sources 4.5-i
-------
application, <30percert occurs within 1 1 if first month, and 95 percent in three In four months. Evaporation
tak< - place more •Mnvvlv From i,, odium curt- halt>, Kith r.iuphlt 20 percent «>f the diluent ln-inp
riinl led during the lir-l d«> , 50 percent during the fir-M week, and 70 percent at'T three to four rn-nth*. No
nru asu red data are available for slow cure be
< onsiderahly less than with >-ilher rapid ur medium cure asphalt;*, and the time during whirh emi*Mon* lake
plate is expected Id br tun? .'derahly lunger ir'igurr 1.5-1). An example calculation for determining \ OC
emissiuns truni culliji k asplialls i» fiveli brluw:
txaniple Local rt-i irds nulirutr that 10,000 kf uf KC cutback asphalt 'containing 45 percent
diluent by volume) wa< applied in a given area during the year. C a U ulaU the nias? nf \ OC.
emitted during thi- year from tint application.
To determine \ OC emit-siun;-. the volume of diluent present in the cutback aspliaJt niu^t
first be delermini-d. Ekcause of density of naplha (O.T kg. I1 differs from that ol asphalt
ce:nem (1. 1 kjt/1), the following equations should be iolvec1. to determine the volume of
diluent (i) and (he volume of asphalt cement (y) in the cutback Mphalt:
10.000 kg cutback asphalt = Ix liter, diluer.U
•* (y liter, asphalt cement) ,
and
K llt«t. diluent - 0.4S (« llt«r, dilutnt -f y llt«r, aaphalt c«Mnt)
t rum these equations, the volume of diluent present in the cutback asphalt i^ determined
to be alniut 4900 liters, or about 3400 kg. Assuming that 95 prrcent of lhi.« ii evaporative
VOC, emissu.n, are ih^ : 3400 kg x 0.95 = 3200 kg (i.t., 32rc . b> weight, of the cutback
asphalt e\ t-ntually evapt.r«te§).
The»e equ.itiun?>caii be used for medium cure and slow cure asphalts by assuming typical diluent densities
L f 0.8 and 0 .9 k^/liler. respeclivf |>. Of roui>e, if actual densil) values are knovvn from local records, thev
should be used in the above equation:- rather than typical values. Also, if different rlih'int . ,mt*nts are
UM>d, they -.liuu.'d also be reflected in the alove calculations. If actual diluent lonlenls an- nu'. known, a
typical value of 35 perron) may be assumed for inventory purpu»es.
In lieu ot solviri); the equations in the above example. Table 4.S-1 may be used tu estima'e In up, term
emissions from c-it iarl Asphalts. T.ible 4.S-1 directly yields long term emissions as a fiincti-'i of the
volume of diluent added to the cutback and uf thf density of the diluenit and asphalt cement used in the
cutback asphalt If abort term emissions are to be estimated, Figure 4.5-] should be useu ' i conjunction
Kith Table 4.5-1.
\<« cor.'rol -levices are fTiipld\ed to reduce evapoi: u«pd in place of cutback asphalt? to ebminate V'Uc emission;.
4.5-2 EMISSION FACTORS 7/79
-------
1MCNTM IMDNTMI
figure 4.5-1. Percent o* diluent evaporated
frorn cutback asphalt over time.
TABLE 4.5-1. EVAPORATIVE VOC
EMISSIONS FROM CUTBACK ASPHALTS
AS A FUNCTION OF DILUENT CONTENT
AND CUTBACK ASPHALT TYPE*1
EMISSION FACTOR RAT|*Q: C
Percent, by Volume,
Type of Cutbackb i of Diluent in Cutbackc
Rapid cure
25%
17
Medium cure 14
£iow cure
5
3b%
24
20
8
45%
32
26
1C
JTh»se nuTitwrs represent the percent, by we ghl of
cutback asphalt evapculed Faclnrs are based on
References 1 and 2
cTypiealdersinesessumeatorCiiuents usedm HC. MC
and SC cjtbacks ari 0.7. 0.8 and 0 9 Kc>ht«r,
respsctivaly
rDiluc'it contents rypically ring* between 25 41% b*
vc-lumt. Emission* n»yb«linpairy i.^terpoiatod for any
given rype t( cutoack between these values
7/79
Evaporation LOFP Source?
4.5-3
-------
References for Section 4.5
1. H. Kcllei and R. Hohn, i\t>i>meiftn.'e Volatile Organic Emissions front Asphalt Cement unit Liquified
Asphalts, EPA-450/3-78-124, L'.S. Eiivipinnu-ntal Protection Agency. Research Triangle Park. NC,
Drcembtr 1976.
2. K. Kirwan and C. Mada). Air Quality and Energy Conservation Benefits from L'finfi Emulsions To
Replace Asphalt Cutbacks it Certain Paving Upetations. EPA-450/2-78-004. U.S. Eriviiuiiinental
Pr itrr!::;n Agcr..-y. Rrscarrh Triaunlc Park. NC, January 1978.
3. David W. Markwordt, Control of Volatile Organic Compounds from Lie of Cutback Asphalt, EPA-
450/2-77-037, U.S. Environmental Pr;»lei'ti«>n Agency. Research Trianfctle Park. NC. December 1977.
4.5-4 EMISSION FACTORS 7/79
-------
4.6 SOLVENT DECREASING
4.6.1 General1''
Solvent decreasing (or solvent cleaning) is the physical
process of using organic solvents to remove grease, fats, ells, wax
or soil from various metal, glass or plastic Items. The types of
equipment uaed in this method are categorized as cold cleaners,
open top vapor degreasers, or conveyorlzed degreaaers. Nonaqueous
solvent^ such ,TS petroleun distillates, chlorinated hydrocarbons,
ketones aii.! alcohols Are. used. Solvent selection is bused on the
solubility of the suh^tance to be removed and on the toxlcity,
flanmability, flash point, evaporation rate, boiling point, cost
and several oth>r properties of the solvent.
The metalworking industries are the ma/lor users of solvent
degreasing, i.e., auto.notive, electronics, plumbing, aircraft,
refrigeration and business machine industries. So*/ent cleaning is
also used in industries such as printing, chercicalc., plastics,
rubber, textiles, glass, paper and electric power. Most repair
stations for transputcatiuu vehicles and electric tools use solvent
cleaning at least pert of the tiLi°.. Many industries use water
based alkaline wash systems for degreasing, and since these systems
emit no solvent vapors to the atmosphere, the> are not included in
this discussion.
Cold Clraners - The two basic types of cold cleaners are maintenance
and manufacturing. Cold cleaners are batch loaded, nonbolling
solvent degreasers, usually providi ig the simplest and least
expensive method of metal cleaning. Maintenance coid cleaners are
smaller, more numerous and generally j^ing petrolf»ura solvents as
mineral spirits (petroleum distillates ai.-i Stoddard solvents).
Manufacturing cold cleaners use a widd vari^*'y of solvents, which
perform more specialized and higher quality cl-^rlng with about
twice th-2 average emission rate of maintenance cold cleaners. Some
cold cleaners can serve both purposes.
Cold cleaner operations include spraying, brushing, flushing
and immersion. In a typical maintenance cleaner (Figure 4.6-1),
dirty parts are cleaned manually by spraying and then soaking in
the tank. After cleaning, the partis are either suspended over tne
tank to drain or are placed on an external racic that routes the
drained solvent back into the cleaner. The cover is intended to be
closed whenever parts are not baing handled in the cleaner. Typical
manufacturing cold cleaners vary widely ip design, but thern ar*
two basic tarvk designs, the simple spray sink and the dip tank. Of
those, the dip f.iik provides inor<» thorough cleaning through
immersion, and often is made to improve cleaning efficiency by
agitation. Small cold cleaning operations may be numerous in urban
areas. However, because of the small quantity of emissions from
ep.^h operation, the large number of individual sources within an
urban area, and the application of small cold cleaning to industrial
4/81 Evaporation Ljs5 Sources 4.6-1
-------
g
i—i
C/5
to
?
o
O
'.n
CARRY OUT
OIFFUSIOMAHD
CONVECTION
CARRY OUT
COLD CLEANER
OPEN TOP VAPOR DEG^EASER
00
Figure 4.&1. Degreaser emission points.
-------
uses not directly associated with degreasing, it is difficult to
identify individual small cold cleaning operations. For these
reasons, factors are provided in Table 4.6-1 to estimate emissions
from small cold cleaning operations over largt urban geographical
areas. Factors in Table 4.6-1 are for nonmethane VOC and Include
25 percent 1,1,1 - trichloroethant , roethylene chloride and
I'-ichlorotri? luoroethane .
TABLE 4.6-1. NONMETHANE VOC EMISSIONS FROM SMALL
COLD CLL..NING DECREASING OPERATIONS
EMISSION FACTOR RATING: C
Per capita
Operating period emission factor
Annual 1.8 kg
4.0 Ib
Diurral 5.8 g
0.013 Ib
.Reference 3.
Assumes a 6 day operating vtek (313 dava/yr).
Opc:n Top Vapor 'Jystems - Open too vapor degreab^rs are batch loaded
bo ling degreaaers that clear: with condensation of hot solvent
vapor on colder metal pari.s. Vapor dtgreaslng uses halogenated
solvents (usually perchloroethylent, trichloroethylene, or 1,1,1-tri-
ch LoroetViaae) , because they ate not flammable and their vapors r.re
mu ,h heavier than air.
A typical vapor degr^a^er (Figure 4.6-1) is a sump containing
a neater that boils thu solvent to generate vapors. The height of
these pure vapors is controlled by condenser coils and/or a water
jacket encircling the device. Solvent and moisture condensed on
the coils are directed to a water separator, where the heavier
solvent ia drawn off the bottom and is returned to the vapor degreaser.
A "freeboard" extends above the top of the vapor zon > t;» minimize
vapor escape. Parts to be cleaned are Iramerseu in the vapor zone,
and condensation continues until they are neated to the vapor
temperature. Residual liquid solvent on the parts rapidly evaporates
as tKoy are slowly removed from the vapor r.one. Lip mounted exhaust
systems carry solvent vapors away from operating personnel. Cleaning
action is often increased by spraying the parte with solvent below
the vapor level or by immersing them in the liquid solvent bath.
Nearly all vapor degreasera are ^quipped with a water separator
which allows the solvent to flow back into the degreaser.
Emission tat^R are usually estimated frrm solvent consumption
daia for the particular degreasing operation under consideration.
4/i!l Evaporation Loss Sources 4.6-3
-------
Solvei.Ls are often purchased tipecif ical ly for use in de-greasing and
are not used in any other plant operations. In these cases, purchase
records provide the necessary Information, and an emisoion factor
of 1,000 kg of volatile organic emissions per metric ton of solveni
purchased can be applied, based on the assumption that all solvent
purcha^d la eventually emitted. When information on solvent
consumption is not available, emission rates can be estimated If
the n-imber and type of degreasing units are known. The facto! s in
Table 4.6-2 are based on the number of degreasers and emissions
produce.: nationwide and may horized degreasars may operate with
either cold or vaporized solver.t, but they merit separate
consideration because they are continuously loaded and are almost
always hooded or en-.losed. About 85 percent are vapor types, and
15 percent are no.iboilinf,.
1-3
4.6.2 Emissions and Controls
Emission^ from cold cleaners occur through (1) waste solvant
evaporation, (?) solvent carryout (iivapor«tion from uet parts),
(3) so?vert bath evaporation, (4) s^ray evaporation, and (5) agitation
(Figure A.6-1). Waste solvent loss, cold cleaning's greatest
emission sourc.3, can be reuuced L rough distillation and transport
of waste solvtat to special incineration olantJ. Draining cleaned
parts for at least 15 secrnda reduces carryout emissions. Bath
evaporation can be controlled by usiing a cover regularly, by allowing
an ,-dequate freeboard htright and by avoiding excessive drafts in
the workshop. If the solvent ased is insoluble in, *nd heavier
than, water, a layer of water two to lour inches thick, covering ."..«:
hal~genated solvent can also reduce bath evaporation. This is
kno>vn as a "water cover". Spraying at low pressure also helps to
reduce solvent loss from this part of the process. Agitation
emissions can be controlled by using a cover, by aRit-iting no
longer than necessary, and by avoiding the use of agitation witfi
low volatility solvents. Emissions nf low volatility solvents
increase -jignlficantly with agitation. However, contrary to what
one might expect, agitation causes only a small increase in emissions
of high volatility solvents. Solvent type is the variable which
:aost affects cold cleaner emitsion rates, particularly the volatility
at operating tenneratures.
EMISSION UACTORS 4/8!
-------
TABLE 4.6-2. SOLVENT LOSS EMISSION FACTORS FOK DECREASING OPERATIONS
EMISSION FACTOR RATING: C
PI
D>
•O
O
r|
P>
Type of dagreasing
All
Cold cleaner
Entire unit
Waste solvent TJ
Solvent carryout
Bath and spray
evaporation
Entire unit
Activity measure
Solvent ci isuraed
Units In operation
Surface area and duty
cycled
Uncontrolled organic
emission factor
1,000 kg/Mg
0.30 Mg/yr/unit
0.165 Mg/yr/unit
0.075 Mg/yr/unit
0.06 Mg/yr/unit
0.4 kg/hr/m2
2,000 Ib/tou
0.33 tons/yr/unlt
0.18 tons/yr/unit
0.08 tons/yr/unit
0.07 tnns/yr/unit
0.08 lb/hr/ft2
o
c.
r\
n
(t
.hane degreaser.
For trichloroethane degreaser. Does not include waste solvent losses.
-------
TABLE 4.6-3. PROJECTED EMISSION REDUCTION FACTORS POK SOLVENT DECREASING
Systea
Control devices
Caver or enclosed design
Drainage facility
Water cover, ref rlgaraf- chiller, carbon
adsorption or high freeboard
Jolld. fl'ild sp.'ay stream
Cold
cleaner
A B
X X
X X
X
X
Vapor Cunveyjrlzed
cegreaoer degreaser
A B A B
X X X X
X X
X X
X
Safety avUc.iea and thermostats
Emission reduction fr">m control devices (')
Operating procedures
PT jper uat of equipment
UaK of high volatility solvent
Waste solvent reclamation
Reduced exhaust ventilation
Reduced conveyor or entry apaad
Emission reduction froft operating
procedures(X)
Total emleaion reductlon(Z)
13-38
X
X
2C-40 JO-60
X
40-60
HA
15-35 20-40 20-30 20-30
23-83* 55-69f 30-oO 45-75 20-30 50-75
Reference 2, Ranges of e»is«i-.i reduction preaent poor to excellent compliance.
X Indicate* devices or procedures which will effect the given reduction*. Letters
A and B Indicate different control device clrcuaetances. See App«nalx B if
bRtferei.;e 2.
Only one of these aajor control devices would b« j«ed in any degreaelng system. System B
could employ any of then. Vjpor degreaeer system B could employ any except watc.r cover.
Conveyarlzed d«gr«a«^r syatea % could employ any except water cover and high freeboard.
jlf agitation by spraying is uaed, the spray should not b« a shower type.
Brsakuut between control equlpeant and operating procedure* is not available.
*A manual or mechanically atilated cover vould contribute 0-181 reduction; draining
parts 15 seconds within the degreaaer, 7-201; and storing vaste so'. vent In containers.
fau additional 15-4>t.
Percentages represent average compliance.
As with cold cleaning, open top vapor degreaslng emissions
relate heavily to proper operating methods. Most emissions are due
to (6) diffusion and convection, which can be reduced by using an
automated cover, by using a manual cover regularly, by spraying
below the vapor level, by optimizing work loads or by using a
refrigerated freeboard chiller (for which a carbon adsorption unit
would be substituted on larger units). Safety switches and
thermostats that prevent emissions during malfunctions and abnormal
operation also reduce diffusion and convection of the vaporized
solvent. Additional sources are (7) so'vent carryout, (8) exhaust
systems and (9) waste solvent evaporation. Carryout is directly
affected by the size and shape of the workload, by racking of parts
aad by cleaning aad drying time. Exhaust emissions can be nearly
eliminated by a carbon adsorber that collects the solvent vapors
for reuse. Waste solvent evaporation is n:>t so much a prohltim with
4.6-6
EMISSION FACTORS
4/81
-------
vapor dfgreasers as it is with cold cleaners, because tbo. halogenated
solvents used are often distilled and recycled by solvent recovery
syuterns.
Because of their large workload capacity and the fact that
they are usually enclosed, conveyorized degreasers emit less solvent
per part cleaned than do either of the other two types of degreaser.
More so th.in operating practices, design and adjustment are major
factors affecting emissions, the main source of which is carryout
of vapor and liquid so1vents.
References for Section 4.6
I. P,J. Marn, et a 1. , Source Assessment^ Solvent Evaporation -
Decreasing. KPA Contract No. T8-02-1874. Monsanto Research
Corporation, Dayton, OH, January 1977.
2. Jeffrey Snv,maker, Control of Volatile Organic Emissions from
So 1yen.t Met A 1 Cleaning. EPA-A50/2-77-0227 U7S.EnvironmeiiLal
Protection -.gency, Research Triangle Park, KG, November 1977.
3. W.H. Latnason, "Technical Discussion of Per Capita Emission
Factors for Several Area Sources of Volatile Organic Compounds",
Office of Air Quality Planning and Standards, U.S. Environmental
Protection Agency, Research Triangle Park, NC, March 15, 1931,
unpubllahad.
4. K.S. Suprenant and D.W. Richards, Study ToSupport New Source
Performance Standards for Solvent^ Metal Cleaning Operations,
EPA Contract No. 68-02-1329, Dow Chumical Company, Midland,
MI, June 1V76.
4/81 Kvaporation Loss Sources 4.6-7
-------
4.7 WASTE SOLVENT RECLAMATION
1-4
4.7.1 Process Description
Waste solvents are organic dissolving agents that are contiminated
with suspended and dissolved solids, organics, water, other solvents,
and/or any substance not added to the solvent during its manufacture.
Reclamation is the process of restoring a waste solvent to a condition
that permits its reuse, either for its original purpose or for jthfr
industrial needs. All waste solvent is not reclaimed, because the cent
of reclamation may exceed the value of the recovered solvent.
Industries that produce waste solvents include solvent refining,
polymerization processes, vegetable oil extraction, metallurgical
operations, pharmaceutical manufacture, surface coating, and cleaning
operations (dry cleaning and solvent degreasing). The amount of solvent
recovered from the waste varies from about 40 to 99 percent, depending
on the extent and characterization of the contamination and on the
recovery process employed.
Design parameters and economic factors determine whether solvent
reclamation is accomplished as a main process by a private contractor,
as an integral part of a main process (such as solvent refining), or as
an added process (as in the surface coating and cleaning industries).
Most contract solvent reprocessing operations recover halogenated hydro-
carbons (e.g., methylene chloride, trichlorotrifluoroethane, anil trich-
luroethylene) from degreasing, and/or aliphatic, aromatic, and naphthenic
solvents such as those used in the paint and coatings industry. They
may also reclaim small quantities of numerous specialty solvents such as
phenols, nitriles, and oils.
The general reclamation scheme for solvent reuse is illustrated in
Figure 4.7-1. Industrial operations may not incorporate all of these
steps. For instance, initial treatment is necessary only when liquid
waste solvents contain dissolved contaminants.
4.7.1.1 Solvent Storage and Handling - Solvents are stored before and
after reclamation in containers ranging in size from 55 gallon (0.2 m3)
drums to tanks with capacities of 20,000 gallons (75 m3) or more.
Storage tanks are of fixed or floating roof design. Venting systems
prevent solvent vapors from creating excessive pressure or vacuum inside
fixed roof tanks.
Handling includes loadlrj; waste solvent into process equipment and
filling drums and tanks prior to transport and storage. The filling is
most oft^n done through submerged or bottom loading.
2/HO K\;i|>or;ili
-------
5TOHACE FUGITIVE FUGITIVE CONDENSER R'CITIVh FUGITIVE STORALt FUGITIVE
T.INK VIWI MISSIONS EMISSIONS VEN, » EMISSIONS EMISSIONS TASK VENT EMISSIONS
INIT1A'
TREATMENT
Q
I DISTILLATION
—T
CATiOM
STORAGE
AND
HANDLING
RECLAIfffD
-SOLVENT
WASTE
DISPOSAL
Q
^INCINERATOR STACK
*-FUCITlVE EMISSIONS
Figure 4.7-1. Genial waste solvent reclamation scheme and emission points.
P*ais5i;i«E ST
AhAlK —— COW. NO WATCH IN
MJJST 1
r— -WArin OJT
i r
M
! li""
1 111
> j — J b — i
uw
r~: n
! -J i
i 1
CAM 1 aero*
— {x}— 1 *;«JS iu-1
Figure 4.7-2. Typical fixed bed activated carbon solvent recovery system.6
1.7-2
KM1SSIO\ FACTORS
-------
Table 4.7-1. EMISSION FACTORS FOR SOLVENT RECLAIMING
EMISSION FACTOR RATING: D
Source
Storage tank
"entb
, en L
Condenser
vent
Incinerator
stack
Incinerator
stack
Fugitive
emissions
Spil laj?e
Load ing
Leaks
Open
sources
Criteria
pollutant
Volatile
organics
Volatile
organics
Volatile
organics
Particulates
Volatile
organics
Volatile
organics
Volatile
organice
Volatile
organics
Emission
Ib/ton
0.02
(0 004-0.09)
3.30
(0.52-8.34)
0.02
1.44
(1.1-2.0)
0.20
0.72
(0.00024-1.42)
NA
NA
factor average
kfc/MT
0.01
(0.002-0.04)
1.65
(0.26-4.17)
0.01
0.72
(0.55-1.0)
0.10
0.36
(0.00013-0.71)
NA
NA
Reference 1. Data obtained from state air pollution control agencies
and presurvey sampling. All emission factors are for uncontrolled
process equipment, except those for the incinerator stack. (Reference
1 does rot, however, specify what the control is on this stack.)
Average factors are derived from the range of data points available.
Factors for these sources are given in terms of pounds per ton and
kilograms per mecric ton of reclaimed solvent. Ranges in parentheses.
.NA - not available.
Storage tank is of fixed roof design.
Only one value available.
4.7 .1.2 Initial Treatment - Wasee solvents are initially treated by
vapor recovery or mechanical separation. Vapor recovery entails removal
of solvent vapors from a gas stream in preparation for further reclaim-
ing operations. In mochanlcal separation, undlssolved solid contaminanr.r
are removed from liquid solvents.
2/80
K\;i|Miniimn !,(>>.» Sonrro
1.7-3
-------
Vapor recovery or collection methods employed include condensation,
adsorption and absorption. Technical feasibility of the method chosen
defends on the solvent's miscibility, vapor composition and concentration,
boiling point, reactivity, and solubility, as well as several o'her
factors.
Condensation of solvent vapors is accomplished by water cooled
condensers and refrigeration units. For adequate recovery, a solvent
vapor concentration well above 0.009 grains per cubic foot (20 ir.g/m^) is
required. To av.o U'. explosive mixtures of a flammable solvent and air in
the process gas stream, air is ruplacud with an inert gaa, such as
nitrogen. Solvent vapors that escape condensation are rticycled through
the main process stream or recovered by adsorption or absorption.
Activated carbon adsorption is the most common method of capturing
solvent emission.-. Adsorption systems are capable of recovering solvont
vapors in concentrations below 0.002 grains per cubic foot (A mg/m3) of
air. Solvents with boiling points of 290°F (200°C) or more do not
L«.sorb effectively with tne low pressure steam commonly used to regen-
erate the carbon beds. Figure A.7-2 shows a flow diagram of a typical
fixed oed activated carbon solvent recovery system. The mixture of
steam and solvent vapor passes to a water cTOled condenser. Water
immiscible solvents are simply decanted to separate the solvent, but
water miscible solvents must be distilled, and solvent mixtures must be
both decanted and distilled. Fluiciized b^d operations are, also in use.
Absorption of solvent vapors is accomplished by pcssing the waste
gas stream through a liquid in scrubbing towers or spray chambers.
Recovery by condensation and adsorption results in a mixture of water
and liquid solvent, while absorption recovery results in an oil and
solvent Mixture, "urther recla.\miag pro* edures are required, if solvent
vapors are collected by sny of these three methods.
Initial treatment of liquid waste solvents is accomplished by
mc;c'.ianical separation methods. This includes both removing water by
decanting and removing undisuolveH solids by filtering, draining,
settling, and/or centrifuging. A combination of initial treatment
methods may ue nccessarv to prepare waste solvents for further
processing.
4.7.1.3 Cist-Illation - After initial treatment, waste solvents are
distilled to remove dissolved impurities anu to separate solvent mix-
tures. Reparation of dissolved impurities is accomplished by simple
batch, simple continuous, or steam distillation. Mixad solvents arc:
separated by multiple simple distillation methods, such as batch or
continuous rectification. Thnse processes are shovn in Figure A.7-3.
In simple distillation, waste solvent is chargeJ co £.n evaporator.
Vaprrs are then continuously removed and condensed, aad the resulting
sludge or still bottoms are drawn off. In steam distillation, solvents
1.7-1 KMISSION r \( I'OH* 2/KO
-------
are vaporized by direct contact with steam which is injected into the
evaporrtor. Simple batch, continuous, and steam distillations follow
Path I in Figure 4.7-3.
The separatic 4 of mlxod solvents requires multiple simple distil-
lation or rectification. Batch and continuous rectification are repre-
sented by Path il in rit»'ire 4.7-3 In batch rectification, solvent
vapors pass through a fraction, ring column, where they contact condensed
solvent (reflux) entering ?: the top of the column. Solvent not returned
as reflux is dravn off as overhead product. In continuous rectification,
the waste solveat feed enters; continuously at an intermediate point in
the column. The more volatile solver "> are drawn ofr at the top, while
those with higher boiling points collect at the bottom.
Design criteria for evaporating vessels depend on waste solvent
composition. Scraped surface stills ci agitated thin film evaporators
are the mout suitable for heat sensitive or viscous materials. Conden-
sation is accomplished by barometric or shell and tube condenserj.
Azeotropic solvent mixtures are separated by the addition of a third
solvent component, while solvents with higaer boiling points, e.g., in
the range of high flash naphthas (310°F, 1558C), are most effectivaly
distilled under vacuum. Purity requirements for the reclaimed solvent
determine the number of distillations, reflux ratios and processing time
needed.
WASTE SOLVENT^
STREAM
EVAPORATION
SOLVENT VAPOR
SOLVENT
VAPOR
r
REFLUX
i
---•> i FRACT10NAT10N J —-H
Hi i
SLUDGE
CONDENSATION
I
DISTILLED SOLVENT
Figure 4.7-3. Distillation process for solvent reclaiming.
i.7.1.4 Purification - Afl-.er distillation, water is removed froia
solvent by decanting or salting. Decanting is accomplished with immis-
cible solvent and water which-, when condensed, form separate liquid
layers, one or the other of which can be drawn off mechanically. Addi-
tional cooling of the solvent/water mix before decanting Increases the
,3eparati'->n of the two components by reducing their solubility. In
silting, solvent is passed through a calcium chloride bed, and water Is
removed by absorption.
j/ao
S
1.7-3
-------
During purification, reclaimed solvents are stabilized, if neces-
sary. Buffers are added to virgin solvents to ensure that pH level is
kept constant curing use. To renew It, special additives are used
during purification. The composition of these additives is considered
proprietary.
4.7.1.5 Waste Disposal - Waste materials separated from solvents during
initial treatment and distillation are disposed of by incineration,
landfill ing or deep well injection. The composition of si'rh waste
varies, depending on the original use of the solvent. But up to 50
percent is unreclaimed solvent, wnich keeps the waste product viscous
yet liquid, thus facilitating pun.ping and handling procedures. The
remainder consists of components such as oils> greases, waxes, deter-
gents, pigments, netal fines, dissolved metals, organics, vegetable
fibers, and resins.
About 80 percent cf !:he waste from solvent reclaiming by private
contractors is disposed of in liquid waste incinerators. About 14
percent is deposited in sanitary landfills, usually in 55 gallon drums.
Deep well injection is the pumping of wastes between inpermeable geologic
strata. Viscous wastes may have to be diluted for ruuping into the
desired stratum level.
1 3-5
4./ ,2 Emissions and Controls '
Volatile organic and particulate emissions result from wa3t« solvent
reclamation. Emission points include storage tank vents [1], condanser
vents [2], incinerator stacks [3], and fugitive losses (numbers refer to
Figures 4.7-1 and -3). Emission factors for these sources are given in
Table 4.7-1.
Solvent storage result.? in volatile organic compound (VOC)
emissions from solvent evaporation (Figure 4.7-1, emission point 1).
The condensation of solvent vapors during distillation (Figure 4.7-3)
also involves VOC emissions, and if steam ejectors are used, emission of
steam a.id noncondcnsables as well (Figures 4.7-1 fnd -3, point 2).
Incinerator star'* emissions consis . of solid contaminants that are
oxidized and released as particulaces, unburned organics, and combustion
stack gases (Figure 4.7-1, point 3).
VOC emissions from equipment leaks, open solvent sources (sludge
drawoff and storage from distillation and initial treatment operations),
solvent loading, and solvent spills are classifed as fugitive. The
former two sources are continuously released, and the latter two,
intermittently.
Solvent reclamation is viewed by industry as a form of crntrol in
itsalf. Carbon adsorption systems can remove up to 95 percent of the
solvent vapors from an air stream. It i= estimated that less than 50
percenc of reclamation plants rui> by private contractor,; use any control
technology.
l.7-(» K.MISSION KACTOKS
-------
Volatile organic emissions from the storage of solvents can be
reduced by as much as 98 percent by converting from fixed to floating
root tanks, although the exact percent reduction also depends on solvent
evaporation rate, ambient temperature, loading rate, and tank capacity.
Tanks may also be refrigerated or equipped with conservation vents which
prevent air inflow and vapor escape until some preset vacuum or pressure
develops.
Solv_ut vapors vented during distillation are controlled by iicrub-
bers and condensers. Direct flame and Catalytic afterburners can also
be used to control noncor.densables and solvent vapors not condensed
during distillation. Th2 time required for complete combustion depends
on the fJammability of the solvent. Carbon or oil adscrptlon may be
employed also, as in the case of vent gases from chc manufacture of
vegetable oils.
Wet scrubbers arr used to remove parriculsr.es from sludge i.icin-
erator exhaust gases, although they do not effectively control subralcron
particles.
Submerged rather than splash filling of storage tanks and tank cars
can reduce solvent emissions from thi? source by more than 50 percent.
Proper plant maintenance and loading p.ocedures reduce emissions from
leaks and spills. Open solvent sources can be covered to reduce these
fugitive emissions.
References for Section 4.7
1, D. R. Tierney and T. W. Hughes, Source Assessment: Reclaiming of
Waste Solvents - State of the Art, EPA-600/2-78/004f, U.S.
Environmental Protection Agency, Cincinnati, OH, April 1978.
2. J. E. Levin and F. Scofield, "An Assessment of the Selv?nt
Reclaiming Industry". Proceedings of the 170th Meeting of the
American Chemical Society, Chicago, IL, 35(2) : .116-418.
August 25-29, 1975.
3. H. K. Rowson, "Design Considerations in Solvent Recovery".
Proceedings of the Metropolitan Engineers' Council on Air Resouces
(MECAR) Symposium on New Developments in Air Pollutant Control, New
York, NY,'October 23, 1961, pp. 110-128.
4. J. C. Cooper and F. T. Cuniff, "Control c.f Solvent Emissif is".
Proceedings of the MetroooUtan Engineers' Council on Air Resources
(MECAR) Symposium on Nt;w Developments in Air Pollution Control, New
York, NY, October 23, 1961, pp. 30-41.
K» iiporalioii l.o>«-
-------
5. W. R. Meyer. "Solvent Broke", Proceedings of TAPPi Testing Paper
Synthetics Conference, Boston. MA, October 7-9. 1574, pp. 109-115.
6. Nathan R. Shaw, "Vapor Adsorption Technology for Recovery of
Chlorinated Hydrocarbons and Other Solvents", Presented at the 80th
Annual Meeting of the Air Pollution Control Association, Boston,
MA, June 15-20, 1975.
1.7-K KMISSION KACTOHS 2/HO
-------
4.8 TANK AND DRUM CLEANING
4.8.1 Genera]
Rail tank c-irs, tank trucks and drums are used to transport about
700 different cornnodities. Rail tank carp and most tank trucks and
druius are In dedicated service (carrying one commodity only) and, unless
contaminated, are cleaned only prior to repair or testing. Nondedicated
tank trucks (about 20,000, or 22 percent, of the total in service) and
drums (approximately 5,6 million, or 12.5 percent of the total) are
cleaned after every trip.
4.8.1.1 Rail Tank Cars - Most rail tank cats are privately owned. Some
cars, like- those owned by the railroads, are operated for hire. The
commodities hauled are 35 percent petroleum products, 20 percent orgai.ic
chemicals. ?5 percent inorganic chemicals, 15 percent compre.sseJ ga^es,
and 5 percent food products. Petroleur products considered in this
atudy are glycols, vinyls, acetones, benzenes, creosote, etc. Not
included ii; these figures are gasoline, diesel oil, fuel oils, jet
fuels, and motor oils, the greatest portion of these being transported
in dedicated service.
Much tank car cleaning is conducted at shipping and receiving
terminals, where th-. wastes go co the manufacturers' treatment systems.
However, 30 to 4'1 percent is done at service stations operated by tank
car owrer/lessors. These installations clean waste of a wide variety of
commodities, many of whii:h require special cleaning methods.
A typical tank car cleaning facility cleans 4 to 10 cars per day.
Car capacity varies from 10,000 to 34,000 gallons (40 - 130 ,n3). Clean-
ing agents include steam, water, detergents and solvents, which a~e
applied using stream hoses, pressure wands, or rotating spray heads
placed through tne opening in the top of the car. Scraping uf hardened
or crystallized products is often necessrry. Cars carrying gases ana
volatile materials, and those needing to be pressure tested, must be
filled or flushed with water. The average amount of residual material
cleaned from each car is estimated to be 550 lb (250 kg). Vapors from
car cleaning non flared or d.'.ssolv>?d in water are dissipated to the
atmosphere.
4.8.1.2 Tank Trucks - Two thirds of the tank trucks in service in the
United States are operated for hire. Of these, 80 percent are used to
haul balk liquids. Most companies operate fleets of five trucks or
less, and whenever possible, these trucks are assigned to dedicated
service. Commodities hauled and cleaned are 1.5 percent petroleum pro-
ducts (except as not<;d in 4.8.1.1), 35 percent organi; chemicals, 5
percent food products, and 10 percent other products.
Interior washing Is carried out at many tank, truck dispatch ter-
minals. Cleaning agents include water, steam, deterge Us, bases, acids
and solvents, which are applied with hand-held pressure wands or by
2/lfO KMijMiruliun !,<»> Soiirro
-------
Tnrco or Butt
-------
not more than 1000'F (480 - 540JC) to prevent warping of the drum.
Emissions ate vented to an afterburner or secondary combustion chamber,
where the gases are raised to at least 1500CF (7. .">°C) for a minimum of
0.5 seconds. The average amount; of material removed from each drum is
4.4 Ib (2 kg).
Table 4.8-2. EMISSION FACTORS FOR TANK TRUCK CLEANING'
EMISSION FACTOR RATING: D
a
Chemical Class
Compound
Acetone
Percnloroethyleno.
Methyl metht-.crj laca
Phenol
Propylsne glycol
Vapor
pressure
high
high
medium
low
low
Total
Visco^i^y emissions
low
Ic ;
medium
low
high
Ib/i-ruck
0.686
0.47*
0.071
0.012
0.002
_£/ truck
311
215
32 4
5.5
1.07
Reference 1. Or.e hour test deration.
4.8.2 Emissions and Controls
4.8.2.1 Rail Tank Cars and Tank Trucks - Atmospheric emissions from
tflnk cai. and truck cleaning are predominantly volatile organic chemical
vapors. To achieve a practical hut representative picture of these
emissions, the organic chemicals hauled by the carriers must be broi-en
down into classes of i.J^h, medium ^nd low viscosities and high, medium
r.md low vapor pressures. This is because high viscosity materials do
not drain readily, affecting ti>e quantity cf material regaining Jn the
tank, and hi
-------
Air emissions from drum burning furnaces ara controlled by proper
operation of the afterburner or secondary combustion c hair be r, where gases
are raised to at least 1400°F (760°C) for a miuluura of O.S seconds. This
normally ensures complete combustion of organic material? and prevents the
formation, and subsequent release, of large quantities of NCX, CO and
partlculatea. In open burning, however, there Is no feasible way of con-
trolling the release of Incomplete combustion products to the atmosphere.
Conversion of open cleaning onerationa to closed cycle cleaning and elim-
ination of open air drum burning seem to be the only control alternatives
Immediately available.
Table 4.8-3 gives emission factors for representative criteria
pollutants emitted fro'a drum burning and cleaning.
TABLE 4.8-3. EMISSION FACTORS FOR DRUM BURNINGa
EMISSION FACTOR RATING: E
Pollutant
Partlculate
NOX
voc
Total Emissions
Controlled
It/drum g/drum
0. 0264 6
0.00004
12b
0.018
negligible
Uncontrolled
Ib/drum g/drum
0.035
O.OC2
16
0.89
negligible
aReference 1. Emission factors are In terms of weight of pollutant
released per drum burned, except for VOC, which cie per drum washed.
''Reference I, Table 17 and Appendix A.
Reference for Section 4.8
1. T. R. Blackwood, et al. , Source Assessment- Rail Tank Car, Tank Truck,
and Cfurn Cleaning. State of the Art, EPA-600/2-7a-004g, U. S. Envltan-
mental Protection Agency, Research Triangle Park, NC, April 1978.
4.8-4
EMISSION FACTORS
2/80
-------
4.9 GRAPHIC ARTS
4.9.1 General
Process Description - The term "graphic arts" as used here means
four basic processes of the printing industry: web offset lithography,
web letterpress, rotogravure and flexography. Screen printing and
manual and sheet fed techniques are not included in this discussion.
Printing muy be performed on coated or uncoated paper and on
other surfaces, as in metal decorating and some fabric coating
(sta Section 4.2, Industrial Surface Coating). The material to
receive the printing is called th° substrate, The distinction
between printing and paper coating, which may employ rotogravure or
lithographic methods, is that printing invariably involves the
application of ink by a printing press. However, printing and
paper coating have these elements in common: application of a
relatively high solvent content material to the surface of a moving
web or film, rapid solvent evaporation by movement of heated air
across the wet surface, and solvent laden air exhausted from the
system.
Printing inks vary widely in composition, but all consist of
three major components: pigu.ents, which produce the desired colors
and are composed of finely divided organic and inorganic materials;
binders, the solid components that lock the pigments to the substrate
and are composed of organic resins and polymers or, in some inks,
oils and rosins; and solvents, which dissolve or disperse The
pigments and oinders and are usually composed of organic compounds.
The binder and solvent make >\p the "vehicle" part of the ink. The
solvent evaporates from the ink into the atmosphere during the
drying process.
Web Oftset Lithography - Lithography, the process used to produce
about 75 percent of books and pamphlets and an increasing number of
newspapers, is characterized by a planographic image carrier
(i.e., the image and nonimage areas are on the same ,. lane). The
image area is ink wettablc and water rapeilarit, and the nonimage
area is chemically repellant to ink. The solution uued ro dampen
the plate may contain 15 to 30 percent isopropariOi, if the Dalgren
dampening system is used.8 When the image is applied to a rubber
covered "blanket" cylinder and then transferred onto the substrate.
the process ia known as "offset" lithography. When a web (i.e., a
continuous roll) of paper is employed with the offset process, this
is known as web offset printing. Figure 4.9-1 illustrates a web
oftset lithography publication printing line. A web newspaper
printing Line contains no dryer, becaude the ink contains ^ery
little solvent, ai.d somewhat porous paper is generally used.
Web offset employs "heatsnt" (i.e., heat drying offset) inks
that dry "t>ry quickly. For publication work the inks contain about
40 percent solvent, and for newspaper work 5 percent solvent is
used. In both cases, the solvfits are usually petroleum derived
4/81 Evaporation Loss Sources 4.9-1
-------
j 1
I THERMAL OR '
QAS (-1 CATALYTIC J
, INCINERATOR'
L---
I
INK SOLVENT AND
1-RMAl DEGRADATION
PRODUCTS
HEAT |
I EXCHANGER I
EXHAUST FAN
SHELL AND
FLAT TUBE
HEAT
EXCHANGER
COMBUSTION
PRODUCTS.
UNBURNED
ORGANICS,
0, DEPLETED
AIR
Q
-FRESH AIR
FAN
GAS
•*•
HEATSET
IN*
INK SOLVENT AND
THERMAL DEGRADATION
PRODUCTS
AIR AND SMOKE
WASHUP .
SOLVENTS.
WEB
WATER AND
ISOPROPANOL
VAPOR
1
WASHUP
SOLVENTS
WATER
—*• WATER AND
ISOPROPANOL VAPOR
PRINTED WEB
AIR
AIR
ISOPROPAMOL
(WITHDALGHEN
DAMPENING SYSTEM)
Figure 4.9 1. W«b offsot lithi>griptiy publication printing Mm (mission points.
11
4.9-2
KMJSS.r.ON
4/81
-------
hydrocarbon*. In a publication web offset process, the web la
printed on both aides simultaneously and parsed through a tunnel or
flo.iter dryer at about 200-2909C C+OO-SOO'F) . The dryer may be hot
air or direct flame. Approximately 40 perceii'. of the incoming
solvent regains in the ink film, and more may be thermally degraded
in a direct flame dryer. The web passes ove** chill rolls before
folding and cutting. In newspaper work no dryer is used, and raost
of the solvent 19 belie\ed to remain in the ink film on the paper. ^
Web Letterpress - Letterpress is the oldest form of raoveable type
printing, and it still dominates in periodical and newspaper publish-
ing, although numerous major newspapers are converging to web offset.
In letterpreas printing, the image area is raised, and the ink is
transferred to the paper directly from the image surface The
image carrier may be made of metal or plastic. Only web presses
u^ing solventborne inks are discussed here. Letterpress newspaper
and sheet fed printing use oxldative drying inks, not a source of
volatile organic emissions. Flgi_re 4.9-2 shows one unit of a web
publication letterpress line.
Publication letterpress printing uses a paper web that is
printed on one side at a time and dried after each color is applied.
The inks employed are heatset, usually of about 40 volume percent
solvent. The solvent in high speed operations is generally a
selected petroleum fraction akin to kerosene and fuel oil, with a
boiling point of 200-370°C <400-700°F) .13
Rotogravure - In gravure printing, the image area is engraved, or
"intaglio" relative to the surface of the image carrier, which is a
copper plated steel cylinder that is usually also chrome plated to
enhance wear resistance. The gravure cylinder rotates in an ink
trough or fountain. The ink is picked up in the engraved area, and
ink Is scraped off the non image. artJ with a steel "doctor blade".
The image is transferred directly to the web when it is pressed
against the cylinder by a rubber covered Impression roll, and the
product is then dried. Rotary Bravura (wub fed) systems are known
as "rotogravure" presses.
Rotogravure can produce illustrations wlM excellent color
control, and it may be used on coated or ancoati-d paper, film, foil
and almos't every other type of substrate. Its use is concentrated
in publications and advertising such as newspaper supplements,
magazines and mall order catalogues; folding cartons and other
flexib1^ packaging materials; and specialty products such as wall
end floor coverings, decorated household i>aper products and vinyl
upholstery. Figure 4.9-3 1 lluatntes one unit of a publication
press. Multiple units are required for priiiting multiple
The inks us
4/81 Evaporation Loss Sources 4.9-3
-------
WEB-
THERMAL j
"H INCINERATOR P
1 1
- -j___.
I
GAS HEAT |
EXCHANGER j
»1
L___
EXHAUST FAN^"
i
FAN ^\
i t
— t
HEATSET INK
__, COMBUSTION
j PRODUCTS,
") UNBUHNED
11 ROTARY 1 ORGANICS,
* HtAL) r ~* l^DEI LLltu
J =2 1 Al"
1 1 ^ '" ^ EXCHGR ~ I He»n AIM
| FILTER | | FILTER | — — '
f"\flM ' TAS t ONLY WHEN
Vj FAN G1S CATALYliC
I 1 UNIT IS
».. _ ,- t_ -. USE'3HERE
_-_._ ^ j
^ AIR HEATER J CATALYTIC )
FOR DRYER "] INCINERATOR j
i !
GAS JMj SUPPLY FAN
»_-.-- - f\. ^ _.
SOLVENT AND THERMAL AIR AND SMOKE
DEGRADATION
PRODUCTS
TUNNEL OR
""" flBYFB "" ROLLS ~~
"-WASHUP OHYtH
•—SOLVENTS
AIR
TTT
COOL WATER
Figure 4.9-2. Web letterprasi publication printing line emiision points.
KAC.TIJKS
Wbi
-------
solvents include alcohols, alaphatic naphthas, aromatic Hydrocarbons.
esters, glyrol ethers, ketonet and nitroparaffins. Water base
Inks are in regular production use in some packaging and specialty
applications, such as sugar bags
Rotogravure is similar to letterpress printing in that the web
is printed on one side at a time and must be dried after application
of each color. Thus, for four color, two sided publication printing,
eight presses are employed, each including a pass over a steam drum
or through a hot air dryer at temperatures from ambient up to 120*C
(250°F) where nearly all of the solvent is removed. For further
information, ste Section 4.9.2.
Flexography - In flexographic printing, as in letterpress, the image
area is above the surface of the plate. The distinction is that
flexography uses a rubber image carrier and alcohol bast inks. The
process i* usually web fed and is employed for medium or long
multicolor runs on a variety of substrates, including heavy paper,
fiberboard and metal and plastic foil. The major categories of the
flexography market are flexiMe packaging and laminates, multiwall
bags, milk cartons, gift wrap, folding cartons, corrugated paperboard
(which is shfcf.t fed), paper cups ancl plctes, labels, tapes and
envelopes. Almost all milk cartons and multiwall bags and half of
all flexible packaging are printed by this process.
Steam set inks, employed in the "water flexo" or "steam set
flexc" process, are low viscosity inks of a paste consistency that
are gelled by water or steam. Steam set inks are used for paper
bag printing, and they produce no significant emissions. Water
base inks, usually piguiented suspensions in water, are also available
for some rlexographdc operations, such as the printing of multiwall
br.gs.
Solvent base inks are used primarily in publication printing,
as shown in Figvr° 4.9-3. As with rotogravure, flexography publi-
cation printing uses very fluid inks of about 75 volume percent
organic solvent. The solvent, which must be rubber compatible, nay
be alcohol, or alcohol mixed with an aliphatic hydrocarbon or
ester. Typical solvents also include glyco^, k=tones and ethers.
The inks dry by solvent absorption into the web and by evaporation,
usually in hign velocity steam, drum or hot air dryers, at temper-
atures below 120"C (250°F) .3'1-* As in letterp t'ess publishing, the
wub is printed on only one side at a time. Thi web passim ever
chill rolls after drying.
Emissions and Controls - Significant emissic-ns from printing
operations consist primarily of volatile organic solvents. Such
emissions vary with printing process, ink formulation and coverage,
press size and speed, and operating time. The type of paper (coated
or uncoated) has little effect on the quantity of emissions, although
low Levels of organic emissions are derived from the paper stock
4/81 Evaporation loss Scurcec 4.9-3
-------
TO A O.
1
^SPHERE
TRACES OF
WATER
AND
SOLVENT
HOT WATEK
__t
1 ] 1
JCONDENSEHJ , DECANTER
f"
SOLVENT!
TVIIXTURFi
' . '«TII
1
1
i
1
1-
1
1-
.Ll
*•• '• l"*| ' "" 1 -"
COOL WATER
STEAM PLUS
SOLVENT
VAPOR . *——-- — — —
.__ i ADSORBER •
'*" j (ACTIVE MODE) *" "
ADSORBER '
f— |
^
STEAM
r
i
i_
If
SOLVENTS
'»
— —»• 'VATER
COMBUSTION
PRODUCTS
t ,
1
STEAM 90ILER |
ii r
WATER
SOLVENT LADE M AIR
WEB-
INK
j
INK
FOUNTAIN
i ,
PRESS
IOMC UNM)
STEAM
i
DRUM OR
HOT AIR DRYER
~T T
AIR AIR
CHILL
ROLLS
11 J.
1
HEAT COOL WATER
FROM STEAM,
HOT WATER.
OR HOT AIR
PRINTEDWE8
Figure 4.0-3. Rotoflravura and fltxognphy prinling ii » emitilon pointi (chill rolls not
used in rotr>gravuie publication printing).^
4.9-6
EMISSION KALTUKS
4/81
-------
during drying.1-' High volume web fed presses such as those discussed
above are the principal sources of solvent vapors. Total annual
emissions from the Industry in 1977 were estimated to be 380.000 Hg
(418,QUO tons). Of this total, lithography emits 28 percent, letter -
preaa 18 psrcent, gravure 41 percent and flexugraphy 13 percent.^
Host of the solvent contained in the ink. ami used for dampening
and cleanup eventually finds its way into the atmosphere, but some
solvent remains with the printed product leaving the plant and Is
released to the atmosphere later. Overall solvent emissions can be
computed from Equation I using a material balance concept, except
in caB?s where a direct flame dryer la used and some of the solvent
is themally degraded.
The density of naphtha base solvent at 21*C (70°F) is
6.2 pounds per gallon.
total
wheia
E . • total solvent emissions including those from the
printed product, kg (Ib)
T - total solvent use including solvent contained in
ink as used, kg (Ib)
The solvent emissions from the dryer and other print line
i.-sents can be computed from Equation 2. The remaining solvent
leaves the plant with the printed product and/or la degraded in the
dryer.
. ISd (100 - P)
100 LOO
where
E - Moivent emissions from Printline, kg (Ib)
1 • Ink use, liters (gallons)
d • solvent density, kg/liter (Ib/gallon)
S and P - factors from Table A. 9-1
Per Capita Emission Factors - Although major sources contribute
roost of the emissions for graphic arts operations, considerable
emissions also originate from minor graphic arts applications,
Including inhouse printing services in general industries. Small
sources within the graphic arts industry arc numerous and difficult
to identify, since many applications are associated with nonprinting
4/81
Evaporation Loss Sources
4.9-7
-------
TABLE 4.9-1.
TYPICAL PARAMETERS FOR COMPUTING SOLVENT EMISSIONS
FROM PRINTING LIMESa'b
Process
Solvent
Content of Ink
(Volume Z) [S]
Solvent Remaining
in Product and
Destroyed in Dryer
(%) IP]C
Emission
Factor
Rating
Web Offset
Publication
Newspaper
Web Letterpress
Publication
Newspaper
40
40
0
40 (hot air dryer) B
60 (direct flame dryer)
100 B
40
(not applicable)
Rotogravure
Flexography
75
75
2-7
2 - 7
C
C
References 1 and 14.
Values for S ard P are typical. Specific values for S and P
.should be obtained rrom a source to estimate its emissions.
For certain packaging products, amount of solvent retained is
regulated by FDA.
TABLE 4.9-2. PER CAPITA NONMETHANE VOC EMISSION
FACTORS °OR SMALL GRAPHIC ARTS APPLICATIONS
EMISSION FACTOR RATING: D
Units
Emitaion Factor
kg/year/capita
Ib/year/capita
g/day/capita
Ib/day/ctpita
0.4
0.8
1
0.003
^Reference 15, All nonmethane VOC.
Assumes a 6 day operating week (313 days/yr).
industries. Table 4.9-2 presents per capita factors for estimating
emissions from small graphic arts operations. The factors are
entirely nonmethane VOC and should be used for emission estimates
over broad geographical areas.
Web Offset Lithography - Emission points on web offset lithography
publication printing lines Include (1) the Ink fountains, (2 the
4.9-8
EMISSION FACTORS
4/81
-------
dampening system, (3) the plate and blanket cylinders, (4) the
dryer, (5) the chill rolla and (6) the product, (see Figure 4.9-1).
Alcohol is emitted from Points 2 and 3. Washiif solvents are a
small source of emissions fron Points 1 and 3. Drying (Point 4) is
the major source, because 40 to 60 percent of the ink solvent is
reaoved from the web during this process.
The quantity of web offsat emissions may bo estimated from
Equation 1, or from Equation 2 and the appropriate data from
Table 4.9-1.
Web Letterpress - Emission points on web letterpress publication
printing lines are: the press (includes the ima^e carrier and
inking mechanism), the dryer, the chill rolls and the product (see
Figure -4.9-2).
Web letterpress publication printing produces significant
emissions, primarily from the ink solvent, about 60 percent of
which is lost in the drying process. Washup rolvents are a small
source of emissions. The quantity of emissions can be computed as
described for web offset.
Letterpress publication printing uses a variety of papers and
inks that lead to emission control problems, but losses can be
reduced by a thermal or catalytic incinerator, either of which may
be coupled with a heat exchanger.
Rotogravure - Emissions from rotogravure printing occur at the ink
fountain, the press, the dryer and the chill rolls (see figure 4.9-3).
The dryer is the major emission point, because most of the VOC in
the low boiling ink i3 removed during drying. The quantity of
emissions can be computed from Equation 1, or from Equation 2 and
the appropriate parameters from Table 4.9-1.
Vapor capture systems are necessary to minimize fugitive
solvent vapor loss around the ink fountain and at the chill rolls.
Fume incinerators and carbon adsorbers are the only devices that
have a high efficiency in controlling vapors Eroii rotogravure
operations.
Solvent recovery by carbon adsorption systems has botii quite
successful at a number of large publication rotogravure plants.
These presses use a single water immiscible solvent (tol lene) or a
simple mixture that can be recovered in approximately the propor-
tions used ii the ink. All i.ew publication gravure plants are
being designed to include solvent recovery.
Some smaller rotogravure operations, such as those that print.
and roat pacl -iging materials, use complex solvent mixtures in which
many of the solvents are water soluble. Thermal incineration with
h«.-at irecovery is usually the most feasible control for such operations,
4/81 Evaporation Loss Sources 4.9-9
-------
TABLE A.9-3. ESTIMATED CONTROL TECHNOLOGY EFFICIENCIES
FCR PRINTING LINES
Reduction In
Method Application Organic Emissions
Carbon adsorption Publication rotogravure
operations 75
b c
Incineration Web offset lithography 95 .
Web letterpress 95
Packaging rotogravure
printing operations 65'
Flexography printing
operations 60
Water-borne inks Some packaging rotogravure
printing operations^ 65-75
Some flexography packaging
printing operations 60
Reference 3. Overall emission reduction efficiency (capture
.efficiency multiplied by control device efficiency).
Direct flame (.thermal) catalytic and pebble bed. Three or more
..pebble beds in a system have a heat recovery efficiency of 852.
^Reference 12. Efficiency of volatile organic removal - does not
.consider capture efficiency.
Reference 13. Efficiency of volatile organic removal - does not
consider capture efficiency.
Solvent porti.cn consists of 75 volume % water and 25 volume %
.organic solvent.
With less demanding quality requirements.
With adequate primary and secondary heat recovery, the amount of
fuel required to operate both the incinerator and the dryer system
can be reduced to lesa than that normally required to operate the
dryer alone.
In addition to thermal and catalytic incinerators, pebble bed
Incinerators are ali»o available. Pebble bed incinerators combine
the functions of a ht'.at exchanger and c combustion device, and c&n
achieve a heat recovery efficiency of 85 percent.
VOC emissions can also be reduced by using low solvent inks.
Waterborne inks, in which the volatile portion contains up to
20 volume, percent water soluble organic compounds, are used
extensively in rotogravure printing of multiwall bags, corrugated
paperboard and other packaging products, although water absorption
into the paper limits the amount of waterborne ink that can be
printed on thin stock before th« web id seriously weakened.
4.9-10 EMISSION FACTORS
-------
Flexography - Emission points on flexographic printing lines are
the ink fountain, the press, the dryer and the chill rolls (sea
Figure 4.9-3). The dryer is the major emission point, and emissions
i.an be estimated from Equation L, or from Equation 2 and the
appropriate parameters from Table 4.9-1.
Vapor capture systems are necessaiy to minimize fugitive
solvent vapor loss around the ink fountain and at the chill rolls.
Fu;ne incinerators are the only devices proven highly efficient in
controlling vapors from flexographic operations. VOC emissions can
also be reduced by using waterborne Inks, which are used extensively
in flexcgraphic printing of packaging products.
Table 4.9-3 shows estimated control efficiencies for printing
operations.
References for Section 4.9
1. "Air Pollution Control Technology Applicable to 26 Sources of
Volatile Organic Compounds", Office of Air Quality Planning
and Standards, U.S. Environmental Protection Agency, Research
Triangle Park, NC, May 27, 1977. Unpublished.
2. Peter N. Formica, Controlled and Uncontrolled Emission Rates
and Applicable Limitations for Eighty Proceoocb, EFA-340 '1-78-004,
U.S. Environmental Protection Agency, Research Triangle Park,
NC, April 1978.
J. Edwin J. Vincent and William M. Vatavuk, Control of Volarlle
Organic Emissions from Existing Stationary Sources, VolumeVIII;
Graphic Arts - Rotogravure and Flexography, EPA-450/f-78-033,
U.S. Environmental Protection Agency, Research Triangle Park,
!'C, December 1978.
4. Telephone communication with C.M. Higby, Gal/Ink, Berkeley, CA,
March 28, 1978.
5. T.W. Hughes, et a1., PriorltIzation of AIr J*ollution from
Industrial Surface Coating Operations, EPA-650/2-75-019a, U.S.
Environmental Protection Agency, Research Triangle Park, NC,
February 1975.
6. Harvey F. George, "Gravure Industry's Environmental Program",
Environmental Aspects of Chemical Use in Printing Operations,
EPA-56C/1-75-005, U.S. Environmental Protection Agency, Research
Triangle Park, NC, January 1976.
7. K.A. Bownes, "Material of Fiexography1', ibid.
8. Ben H. Carpenter and Garland R. Hilliard, "Ovatview of Printing
Processes ar.'I Chemicals Used", ibid.
4/81 Evaporation Loss Sources 4.9-11
-------
9. R.I, Karvir., "Recovery and Reuse of Organic Ink Solvents",
ibid.
10. Joseph L. Zborovsky, "Current Status of Web Heatset Emission
Control Technology", ibid.
11. R.R. Gadomski, et al., Evaluations of Emission and Control
Technologies in the Graphic Arts Industries, Phas3 I: Final
Report, APTD-0597, National Air Pollution Control Administration,
Cincinnati, OH, August 1970.
12. R.R. Cadotnski, <5t al., Evaluations of Emissions and Control
Technologies in~:ihe Graphic Arts Industries, Phase 11; Web
Offset audMetal Decorating Processess, APTD-1463, U.S.
Environmental Protection Agency, Research Triangle Park, NC,
May 1973.
13. Control Techniques forVolatile OrganicEmissions from
Stationary Sourres. EPA-450/2-78-022, U.S. Environmental
Protection Agency, Research Triangle Park, NC, May 1978.
14. Telephone communication with Edwin J. Vincent, Office of Air
Quality Planning and Standards, U.S. Environmental Protection
Agency, Research Triangle Park, NC, July 1979.
15. W.H. Lamason, "Technical Discussion of Per Capita Emission
Factors for Several Area Sources of Volatile Organic Compounds",
Office of Air Quality Planning and Standards, U.S. Environmental
Protection Agency, Research Triangle Park, ^C, March 15, 1981.
Unpublished.
4.9-1? EMISSION FACTORS 4/81
-------
4.9.2 PUBLICATION GRAVURE PRINTING
1-2
Process Description - Publication gravure printing 13 the printing
by the rotogravure process of a variety of paper products such as
magazines, catalogs, newspaper supplements and preprinted Inserts,
and advertisements. Publication printing is the largest sector
involved in gravure printing, representing over 37 percent of the
total *ravure product sales valve in a 1976 study.
The rotogravure press Is designed to operate as a continuous
printing facility, and normal operation may be either continuous or
nearly so. Normal press operation experiences numerous shjtdown^
caused by *eb breaks or mechanical problems. Each rotogravur-.i
oress generally consists of eight to sixteen Indi/idual printing
units, with an eight unit press the most common. In publication
printing, only four colors cf ink are used, yellow, red, blue and
black. Fach unit prints one ink color on one side of the web, aad
colors other than these four are produced by printing one color
over another to yield the desired product.
In the rotogravure printing process, a web or substrate from a
continuous voll is passed over the image surface of a revolving
gravure cylinder. For publication printing, only paper uebs are
used. The println. impges ar•> formed by many tiny recesses or
cells etched or ".ngraved into the surface of the gravure cylinder.
The cylinder is about one fouitli submerged in a fountain of low
viscosity mi"ed ink. Raw ink !
-------
1 3-4
Emissions and Controls ' - Volatile organic compound (VOC) vapors
are the only significant air pollutant emissions from publication
rotogravure printing. Emissions from the printing presses depend
on the total amount of solvent used. The sources of these VOC
emissions are the solvent components in the raw inks, related
coati-igs used at the printing presses, and solvent added for dilu-
tion and press cleaning. These solvent organics are photuchemically
reactive. VOC emissions from both controlled and uncontrolled publi-
cation rotogravure facilities in 1977 were about 57,000 megagrams
(63,000 tons), 15 percent of the total from the graphic arts industry.
Emissions from ink and solvent storage and transfer facilities are
not considered here.
Table 4.9-1 presents emission factors for publication printing
on rotogravure presses with and without control equipmett. The
potential amount of VOC emissions from the press is equal to the
total amount cf solvent consumed In the printing process (see
Footnote f ) . For uncontrolled presses, emissions occur from the
dryer exhaust vents, printing fugitive vapors, and evaporation of
solvent retained in the printed product. About 75 to 90 percent
of the VOC emissions occur from the dryer exhausts, depending on
press operating speed, press shutdown frequency, Ink and solvent
composition, product printed, and dryer designs and efficiencies.
The amount of solvent retained by the various rotogravure printed
products Is three to tour percent of the total solvent In the ink
used. The retained solvent eventually evaporates after the printed
product leaves the press.
There are numerous points around the printing press from
which fugitive emissions occur. Mos»t of the fugitive vapors result
from solvent evaporation in the ink fountain, exposed parts of the
gravur» cylinder, the paper path at the dryer Inlet, and from the
paper web after exiting, the dryers between printing units. The
quantity of fugitive vapors depends on the solvent volatility, the
temperature of the xnk and solvent in the ink fountain, the amount
of exposed area around the press, dryer designs and efficiencies,
and the frequency of pres. slutdowns.
The complete aJr pollution control system for a modern
publication rotogravure printing facility consists of two sections,
the solvent vapor capture syst'^r and the emission control device.
The capture system collects VOC vapors emitted from the presses and
directs them to a control device where they are either recovered or
destroyed. Low-VOC waterbcrne ink systems to replace a significant
amount of solventborne inks have not been developed a:, an emission
reduction alternative.
Capture Systems - Presently, only the concentrated dryer
exhaua'.s are captured at most facilities. The dryer e-.hausts
contain the majority of the VOC vapors emitted. The capture
efficiency of dryers is limited by their operating temperatures and
4.9 2-2 EMISSION FACTORS 4/81
-------
TO NEXT UNIT
DRYER EXIT AIR FLOW
RECIRCVLATION
FAK
o
1-1
o
ADJUSTABLE
COMPENSATING
ROLLER
DOCTOR BLADE
TOORVER
EXHAUST
HEADER
M I—EXTENDER/VARNISH
M | INK
SOLVENT
CIRCULATION
PUMP
LIQUID VOLUME METERS
Figure 4.9.2-1. Diagram of a rotogravure [Tinting unit.
-------
TABLE 4.9.2-L. QUSSION FACTORS FOR PUBLICATION ROTOGRAVURE PRINTING PRESSES
EMISSION FACTOR RATING: C
i°
i
ti
X
to
in
O
o
t/i
llnrtMil riil 1 1'rj
lolnl
NIllvPIII K.ltl
r»lssl.in kg/kg k^
I'.iliils (ll./lh) llti-i
l)t yci ^«li^-.«r-. ' U.H4 1.7.4
Fugll (»<•*' 0. ! 1 II. '<*
i
rrlnK-,1 pr<>.lii< 1 U.lll H. US
l.iinlrnl ili'vlrr
- j -. - -
lol:ll .-•!,, l.ili^ l.il I.'.H
__._._ _.._..... ^
i.ui-slst enllrrly xarl.i vllh
II MMl " 1 H ll
Knliiv ratio aclrralnrd fr
I^I.H,a"
MM < Mill rol
Tutal
Ink a-| O.U7 H.I'J
- *
1 .mil Ifst iliii.i fni |ni'N:.«-H wll'i 'Iryor I*X|MIIrris -ihiildiiuu I •rq.N'iir ik< Jr t*l pfrn* Fal •• Inrr? .
lk*l fl mliiftl h]r illf I <*r i-nri* iirlwi'll lot.il •'nlssliilis llld ntlirr ptllat nl union* .
' H.-l , i i-ii' " I. Solx'iit t'.»^Mrj| I I y ipl.iliicil In |ir.i '*",* !«<• I - 71 nf lolal |irra> rmlnm liim .
HJMI'C! mi r.i|itiir«' mhl riintriil i!«*vlrf f*l I Ir l4>nr Im ( wp Note f}. Failniiliiflti aip rmldual nMllpnl (n rapluri'd nulirriit ladrtl
(.lfr vpiili'.l afltr 1 1 c;il mpiit .
Kili'irnir-; ' ^IM| ). Ihi. .i;il rol l<-«1 |ir»isi-it rvpnliM I I y mil HWZ of «nt«l nnlveiil lined. Controlled prua r«l««l.w>« *tf
lism-il .in overall i.-.lnr t |i,.< rfflclrmy r<|ii I I
-------
other factors that affect the release of the solvent vapors from
the print and web to the dryer air. Excessively high temperatures
inpalr product quality. The capture efficiency of older design
dryer exhaust systems is about 84 percent, and modern dryer systems
can achlevr*. 85 to 89 percent capture. For a typical press, this
type cupt*-e system consists of ductwork from each printing unit's
dryer exhaust joined in a large header. One or more large fans are
employed to pull the solvent laden air from the dryers and to
direct I:, ta the civ.trol device.
A. few f .rtlities have increas-ed capture efficiency by gathering
fugitive solvent vapors along wit i .he .jryer exhausts. Fugitive
vapors can be captured by a hood above the press, by a putial
enclosure around the press, b> a system of multiple spot pickup
vents, by multiple floor sweep v;nts, hy tocal pressroom vent^la-
tion : a- ' ai •», or by various combinations of these. The desl^r. of
any fugitive vapor capture system ieeds to be versatile enough to
allow gait* and adequate access Co *h' press in press shutoowns,
The efficiencies of these combined dr^er exhaust and fugitive
capture systems can be as high as 93 to 97 percent at tinea, but
the demonstrated arh'evable long tern average when printing several
types of products is only about 90 percent.
Control Devices - Various control devices and techniques nay
be employed to control captured VOC vapors fro-- rotogravure presses.
All such control** are of two categories, solvent recovery and
solvent destruction.
Solvent recovery is the only present technique to control VOC
emissions from publication presses. Fixed bed carbon adsorption by
multiple vessels operating in parallel configuration, regenerated
by steaming, represents the most used control device. A new
adsorption technique using a fluidized bed at carbon might be
employed in the future. The recovered solvent can be directly
recycle.! to the presses.
There are three types of solvent destruction devices used to
control VOC emissions, conventional thcrreal c.xidation, catalytic
oxidation and regenerative thermal combustion. These control
devices are employed for oth*-r rotogravure printing. At present,
none are being used on publication rotogravure presses.
The efficiency of both solvent destruction and solvent recovery
control devices can be as high as 99 p'rcant. However, the
acht'waMe long terra average efficiency for publication printing is
about 95 percent. Older carbon adsorber systems were deripned to
perform at about 90 percent efficiency. Control device eraibsion
factors presented In Table 4.9-1 represent the residual vapor
content of the captured solvent laden air vented after treatment.
Overall Control - The overall emissions reduction, efficiency
for VOC control systems is equal to the capture efficiency tiitras
4/81 Evaporation Loss Sources 4.9.2-5
-------
the control device efficiency. Emission factors foe two Control
levels are presented In Table 4.9.2-1. The 75 percent control level
represents 84 percent capture with a 90 percent efficient control
device. (This 10 the EPA control techniques guideline recommenda-
tion for State regulations on old existing presses.) Th". 85 percent
control level represents 90 percent cap tun. with a 95 percent effi-
cient control device. This corresponds to application of best
demonstrated control technology for new publication presses.
References for Section 4.9.2
1 . Publication Rotogravure Print ing - Background Information for
Proposed S tandardg . EPA-450/3-8Q-G3 la , U.S. Environmental
Protection Agency, Research Triangle Park, NC, October 1980.
2. Publication Rotogravure Pilntlng - Background Information for
P roma 1 ga t ed Standards , EPA- 4 50 / 3-80-0 3 1 b , U.S. Environmental
Protection Agency, Research Triangle Park, NC. Expected
November 1981.
3. I ntroi of Volatile Organic Emissions from '.xlstlng Stationary
Soi-cas, Volume VIII: Graphic Arta - Rotogravure and Flexography,
EPA— 50/2-78-033, U.S. Environmental Protection "/Agency, Research
1-langle Park, NC, December 1978.
4 . Standards of Performance for New Stationary Sourcesj Graphic
AiTta - Publication Rotogravure Printing, 45 FR 71538, October 23.
T5io:
5. Written communication from Texas Color Printers, Inc., Dallas,
TX, to Radian Corp., Durham, NC, July 3, 1979.
6. Written conrnunlcatlon frou> Meredi th/flurda, Lynchburg, VA, tJ
Edwin Vincent, Office of Air Quality Planning and Standards,
U.S Environme cal Protection Agency, Research Triangle Park,
NC, July 6, 1979.
7. V.R. Feairheller, Graphic Arts Emission Teat Report t MereditV/
Burja, Lynchburg, VA, EPA Contract No. 68-02-2818, Monsanto
.Research Corp., Dayton, OH, April 1979.
8. W.R. Fenlrheller, nraphlc ^r_ts ^mls^a^on Test Report, Texas
Color Prirtera. Drllas, TX, EPA Contract No. 68-02-, 18 18,
Monsanto Research Corp., Dayton, OH, October 1979.
4.9.2-6 EMISSION FACTORS 4,'V.
-------
4.10 COHMEKCIAL/CONSUMER SOLVENT USE
^.10.1 General1'2
Commercial and consumer use of various products containing
volatile organic, compounds iVOC) contributes to formation of tropo-
sphet'ic ozone. The organics in these products may be released
through Immediate evaporation of an aerosol spray, evaporation
after application, and direct release in the gaseous phase. Organics
may act either as a carrier for the active product ingredients or
as active ingredients themselves. Commercial and consume-, products
which release volatile organic compounds include aerosols, household
products, toiletries, rubbing compounds, windshield washing fluids,
polishes and waxes, nonindustrial adhesives, space deodorants, moth
control applications, and laundry detergents and treatments.
4,10.2 Emissions
Major volatile organic constituents of these products which
are released to the atmosphere Include special naphtha*, alcohols
and various chloro- and fluorocarbone. Although methane Is not
included In these products, 31 percent of the volatile organic
compounds released in t^ie us*.* of these products Is considered
nonteactive under EPA pnlicy. •*
National emissions and per capita emission factors for commercial
and consujier solvent use are presented in Table 4.10-1. Per capita
emission factors can be applied to area source inventories by
multiplying the factors by Inventory area population. Note that
adjustment to exclude the nonreactlve emissions fraction cited
above should be applied to total emissions or to the composite
factor. Care is advised in making adjustments. In that substitution
o.' compounds within the commercial/cunaumer products market may
a^cer the nonreactlvp fraction of conpounds.
References for Section 4.1U
1. W.H Lamason, "Technical Discussion of Per Capita Emiaiirn
Factors for Several Area Sources of Volatile Organic Compounds",
Monitoring and Data Analysis Division, U.S. Environmental
Piotectlon Agency, Research Triangle Park, NC, March 15, 1981.
Unpublished.
2 . Knd 'Jae of Solvents Containing Volatlie Organic Cnmpounda,
EPA-4507T-79-C32, U.S. Environment;if Protection Agency,
Research Triangle Park, NC, May 1979.
3. Final Emission InvenLory RequirementH fur 1982 Ozone Sttite
Implementationflans, EPA-450/4-80-016, U S. Environmental
Protection Agency, Research Triangle Park, NC, December 1980.
4/81 Evaporation Losrt Sources 4.10-1
-------
TABLE £4.10-1. EVAPORATIVE EMISSIONS FROM COMMERCIAL/CONSUMER SOLVENT USE
EMISSION FACTOR RATING: C
Nonrse thane V<>~
National Emissions
Use
Aerosol products
5 Household products
i-»
K
£ Toiletries
Q
Z
^ Rubbing compounds
n
2 Windshield washing
70
V.
Polishes and waxes
Non Indus trial
Space deodorant
Morn control
Laondry detergent
Total0
103Mg/yr
342
183
13?.
62
61
48
29
18
16
4
895
10 tons/yr
376
201
1*5
68
S3
3?
20
ia
4
984
Per Capita
kg/yr
1.6
0.86
0.64
0.29
0.29
0.22
0.13
0.09
0.07
0.:*
4.2
Ib/yr
3.5
1.9
1.4
0.6^
0.63
0.49
0.29
0.19
0.15
0.04
9.2
Emission Factors
K/day
4.4
2.4
1.8
0.80
0.77
0.59
0.36
0.24
0.19
0.05
11.6
10 3lb/d«y
9.6
5.?
3.8
1.8
1.7
1.3
0.79
0.52
0.41
O.IC
25.2
References 1 and 2.
"Calculate:! by dividing kg/yr (Ib/yr) by 365 and converting to appropriate units.
Totals may ROC be additive because of rounding.
-------
4. Procedures for the Preparation of EaiHalon Inventories for
Volatj.T« Organic Compounds, Volume l7jSecond^E450/
2-77-028, U7s. Environmental Protection Agency, Research
Triangle Paik, NC, September 1980.
4/dl Evaporation lose S.-urces 4.10-3
-------
•..11 TEXTILE FABRIC PRINTING
1-2
A.11.1 Process Description
Textile fabric printing Is part of the textile finishing
Industry* In fabric printing, a decorative pattern or design la
applied to constructed fabric by roller, flat screen or rotary
screen methods • Pollutants of Inteiest in fabric printing are
volatile organic compounds (VOC) from mineral spirit solvents in
print pastes «r inks. TabTea 4.11-1 and 4.11-2 show typical
printing tun characteristics and VOC emission sources, respectively,
for roller, flat screen and rotary acreen printing methods*
In the roller printing process, print paste ie applied to an
engraved roller, and the fabric is guided between it and a central
cylindert The pressure of the roller and central cylinder forces
the print paste Into the fabric* Because of the high quality it can
achieve, roller printing is the most appealing method for printing
designer and fashion apparel fabrics.
la flat screen printing, a screen on which print paste has been
applied is lowered onto a section of fabric* A squeegee then moves
across the screen, forcing the print paste through the aci:e*n and
into the fabric* Flat screen machines are used mostly in printing
terry towels*
In rotary screen printing, tubular screens rotate at the same
velocity ae the fabric. Print paste distributed Inside the tubular
screen is forced into the fabric as it is pressed between the acreen
and a printing blanket (a continuous rubber belt) . Rotary screen
printing machine* .'re used mostly but not exclusively for bottom
weight apparel furies or fabric not for apparel use. Most knit
fabric Is printed by the rotary acreen method, because it does not
stress (pull or stretch) the fabric during the process*
Major print paste components include clear and color
concentrates, a solvent, and in pigment printing, a low crock or
binder resin. Print pa&tp color concentrates contain either
pigments or dyas. Pignents are insoluble particles physically bound
to fabrics. Dyes are in solutions applied to Impart color by
becoming chemically or physically incorporated into individual
fibers. Organic solvents are used almost exclusively with pigments.
Very little organic solvent is used In nonpigment print pastes*
Clear concentrates extend color concentrates to create light and
dark shades. Clear and color concentrates do contain some VOC but
contribute lean than 1 percent of total VOC emissions from textile
printing operations. Defearners and resins are Included in print
paste to Increase color fastness. A small amount of thickening
8/82 Evaporation Losa Sources 4-11-L
-------
TABLE 4.11-1. TYPICAL TEXTILE FABRIC PRINTING RUN CHARACTERISTICS
PI
C/5
W
O
Z
n
H
o
JO
en
Cliaracterliit Ic
Roller
han[.e Average
Rotary screen
Range Average
FLat acreen
Range Average
Wet plrkup rate, kp, (lb)b
print paste consumed/kg
(Ib) of fabrlcc
O.il - 0.58
0.56
0.10 - 1.89
0.58
0.22 - 0.63
0.35
fabric weight. kg/.2 (iWyd2)d 0.116 - 0.116 O.M6 C.IK, - 0.116 0.116 C.314 - 0.314 0.314
(0.213 - 0.211) (0.213) (0.213 - 0.213) (0.213) (0.57* - 0.3/9) (0.57S)
Hli.eral spirits added to
print paste, "eight X
Print paste used per fabric
area. kg/a2 (Ib/yd2)*
Mineral spirits used per
fahrlr a.ea. fcg/m2 (Ib/yd2)£
0-60
0 - SO
21 - 23
0.059 - 0.067 0.06) 0.012 - 0.219 0.067 0.069 - 0.261 0.110
(0.109 - 0.124) (0.119) (0.021-0.403) (0.124) (0. 127 - 0.481) (0.201)
-------
GO
NJ
TABLE 4.11-2.
SOURCES OF MINERAL SPIRIT EMISSIONS FROM A TYPICAL
TFKTILE FABRIC PRINTING RUN3
tr
b
•a
£
'
f
o
m
09
o
8
10
Source
»«'.iv>:-»l spirits
used 1n runb
U.I S U'd Hlllirral
spirits (potpnHvij
Over orint ed nlneral
spirit fugl lvesd
Tia-' ?r.d barrel
fuRH lv«-se
Fl.ishoff fcglcl»esc
L>r>,- ,,.l.,irn:,'
Percent of Holler Rotary icreen
total Range Average Mnge Average
emissions k& Ib kg Ib kg Ib kg Ik
100.0 0-458 0 - J.OflS 191 425 0 - 1,249 0 - 2,754 23 51
3.5 0 - 16 0 - 15 7 15 0 - 44 0-97 1 2
0.1 0-' C-2 1 20-4 0-9 0 0
1.5 0-7 •• • t . J ft 0 - 19 0-41 0 I
88.5 U - 405 0 - 889 170 375 0 - 1,105 0 - 2,436 21 4h
Fill screen
kange Average
kjl U kg Ib
181 - 684 39) - 1,508 28* 635
6-24 13-03 10 22
1-2 1-4 1 2
3-10 6-22 4 9
160 - 606 353 - 1.337 255 562
"Length of ru., • 10,000 m (10,93k yd); f.hrlc uldth - 1.14 • 11.25 yd); total fabric
line speed • 40 m/mln (44 yd/aln); distance, printer to rven • 5 • (5.5 yd).
"Print paste used in run Multiplied, by Mineral bplrlta added to print pacte, weight percent.
cEgf;«ate provided by Industry contacts.
dEsclauttd on the ball 9 of 2.5 rm (1 In.) of overprln' on each aide uf fabric.
pEnlsslon sp'lcs calculated froa percentages provided by evaporation coaiputatlont.
- il,400 m2 (I3,ol4 yd2);
-------
agent is also added Co each print paste t" control print paste
viscosity. Print defoamers, resins and thickening agents do not
contain VOC.
The majority of emissions from print paste are from the
solvent, which may be aqueous, organic (mineral spirits.) or both.
The organic solvent concentration in print pastes may vary from 0 to
60 weight percent;, with no consistent ratio of organic solvent to
water. Mineral spir: ts lined in print pastes vary widely in physical
and chemical proper~.i2s. See Table 4.11-3.
TABLE 4.11-3. TYPICAL INSPECTION VALUES FOR MINERAL SPIRITS*
Parameter
Range
Specific gravity at 15° C (60° F)
Viscosity at 25° C (77° F)
Flash point (closed cup)
Aniline point
Kauri-Butanol number
Distillation range
Initial boiling points
50 percent value
Final boiling points
Composition (%)
Total saturates
Total aromatics
Lg and higher
0.778 - 0.805
0.83 - 0.95 cP
41 - 45° C (105 - 113° F)
43 - 62'
32 - 45
(110
F)
157 - 166° C (315 - 3HO° F)
168 - 178° C (334 - 345 ° F)
199 - 201" C {.390 - 39»° F)
81.5 - 92.3
7.7 - 18.5
'.5 - 18.5
References 2,4.
Although some mineral spirits evaporate in the early stages of
the printing process, the majority nf emissions to the dLmosphere is
from the printed fabric dr> ".ng process, which dri.'ds of' volatile
compounds (ree Table 4.11-2 for typical VOC emissi' c splits). For
some specific print paste/fabric combinations, color fixing occurs
in a curing process, which may be entirely separate cr merely a
separate segment of the drying process.
Two types of dryers are used for printed fabric - steam coil or
natural gas fired dryers, through which the fabric is conveyed on
belts, racks, etc., and steam cans, with which the fabric makes
direct contact, tost screen printed fabrics and practically all
printed knit fabrics and terry towels are dried witn the first type
of tiryjr, not to itr<2ss the fabric. Roller printed fabrics ind
4.11-4
EMISSION FACTORS
-------
apparel fabrics requjring soft hand] ing are dried on steam cans, which
have lower installation and operating costs ar ti which dr». tie fabric
more quickly than other dryers.
Figure A. 11-1 < s a schematic diagram of tht rotary screen printing
process, with emission points indicated. Tnc >.iat sc^f-.cn printing
process is virtually identical. The symbols far fugitive >.'OC «m is si one
to the atmosphere indlcace mineral spirits tv* j'Jrating frcra print paste
during application ro fabric before dr/'.ng. Tie largest VOC eirlsaion
jo'irce is the drying and curing OVIMI stack, which vents evaporated
solvents (mineral spirits and water) to the scin^sphere. lh_ s/ub^l for
fugitive VOC emissions l nlie waste water indicates print pasie mineral
spirits washed with water from the printing blanket (continuous belt)
and discharged in waste water,
Figure 4.11-2 is P schematic diagram of a roller printing process
in which all emissions are fugitive. Fugitive VOC emissions from the
''oack prey" (fabric u
-------
5
M
C/l
CA
BLEACHED
FABRIC
\
t
t
FUGITIVE VOC EMISSIONS TO
ATMOSPHERE
STACK VC : EMISSIONS
FUGITIVE VOC EMISSIONS TO
WA5TEWATER
VENT TO
ATMOSPHERE
DRYING AND CURING
I OVEN
DAY PRINTED
fABRIC
00
ro
Figure 4.T1-1. Schsmstic d(»grBm of the rotary screen printing process,
with fabric drying in a vented oven.
-------
STEAM CANS
CZ
CD
PI
<
tt
•o
c
O
D
51
CD
CO
O
C
1
rj
FUGITIVE VOC EMISSIONS
TO ATMOSPHERE
GHAVUHtHOLLER
LI NT DOC: OR
BRUSH ROLLER
PRINT
PASTE
PRINTED
FABRIC
DRV PRINTED FABRIC
BLEACHED
FABRIC
DRY BACK GREY
TROUGH
Figure 4.11-2. Schematic diagram of ttie roller printing procen,
wrtf. fabric drying on steam cans.
-------
(a function of pattern coverage and fabfic weight), and rate of
fabric processing. With the quantity of fabric printed held
constant, the lowest emission rate represents minimum organic
solvent content print paste and minimum print paste consumption, and
the maximam omission rate represents maximum organic solvent content
print paste and maximum print paste consumption. The a"erage
emission rates shown for roller and rotary screen printing are based
on the results of a VOC jaage survey conducted by the American
Textile Manufacturers Institute, Inc. (ATMi), in M79. Tht average
flat screen printing emission factor Is based on information fvom
two terry towel printers.
TABLE 4.11-4. TEXTILE FAE;'-C PRINTING ORGANIC EMISSION FACTORS3
EMISSION FACTOR RATING: C
Roller
VOC
Range Average
Rotary screen
Average
FUt screen**
Range Average
kg(lb)/l,000 kg
(lb) fabric
Mg
-------
are us :d to derive Che foil benefit of using organic solvents. The
oost accurate emissions da:a can be generated by obtaining organic
solvent use data for a particular facility. The emission factors
presented here should only be used to estimate actual process
emissions.
References for Section 4,. 11
1. Fabric Printing Industry: Background Infornariun fur Proposed
Standards (Draft), fci'A Contract No. 68-02-3056, Research
Triangle Institute, Research Trlaagie Park, i'iC, Ap-j.1 21,
1981.
2, Exxon Petroleum Solvents. L'jbetext DC-IP, Exxon Company,
Hcusfon, TX, 1979.
3. Memorandum from S. 8. York, Research Triangle Institute, to
Textile Fahrio Printing AP-42 file, Office of Air Quality
Planning and Standards, U.S. Envlrontner.tal Protection Agency,
Research Triangle Park, NC, March 25, 1981.
4. C. Marsden, riolvents Guide, Int^rscience f'iblishsrs. New York,
NY, 1963, p. 54&.
5. Letter from W. H. Steenland, ^ueriran Textile Manufacturers
Institute, Inc., to Dennis Cruflpler, U.S. Environmental
Protection Agency, Research Tviangle Park, NC, April 8, 1980.
6. Memorandum from S. 3. York, Research Triangle last'.- ••«•--•, to
textile fabric priming AP-42 file, Office of Air Quality
Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Hark, NC. March 12, 1981.
7. Letter from A. C. Lohr, Burlington Industries, to James Berry,
U.S. Environmental Protection Agency, Res.^arch Triangle Park,
NC, April 26, 1979.
8. Trip Report/Plant Visit to Fieldcraet Mills, Foremost Screen
Print Plant, memorandum from S. B. York, Research Triangle
Institute, to G. Gasperecz, U.S. Environmental Protection
Agency, Research Triangle Park, NC, January 28, 1980.
9. Letter from T. E. Boyce, Fieldcrest Corporation, to S. B. York,
Research Triangle Institute, Research Triangle Park, NC,
January 23, 1980.
10. Telephone conversation, S. B. York, Research Triangle
Institute, with 'IOTP Boyce, Foremost Screen Print Plant,
Stokr.soale, NC, April 24, 1980.
8/32 Evaporation Loss Sources 4.11-9
-------
li. "Average Weight and Uidth of Broadwoven Fabrics (Gray)",
Current Industrla1 Report, Publication No. MC-22T (Supplement),
Bureau of the Census, U.S. Department of Commerce, Washington,
DC, 1977.
12. "Sheets, Pillowcases, and Towels", Current Industrial Report.
Publication No. M2-23X, Bureau of the Census, u,S, Department
of Commerce, Wawhington, DC, 1977.
13. Memorandum from S. B. York, Research Triangle Institute, to
Textile Fabric Printing AP-42 file, Office of Air Quality
Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC, April 3, .'981.
14. "Survey of Plant Capacity, 1977", Current Indus trial Repor t,
Publication No. DQ-Cl(77)-l, Bureau of the Census, U.S.
Department cf Commerce, Washington, DC, August 1978.
4.1J.-10 EMISSION FACTORS
8/82
-------
5.0 CHEMICAL PROCESS INDUSTRY
This Chapter deals w;.th emissions from the manufacture and use of chemicals
or chemical products. Potential emissions from many of these processes are
hi^h, but because of econonic necessity, they are usually recovered. In some
cases, the manufacturing operation is run as a closed system, allowing little
ov no fmissions to escape to the. atmosphere.
The emissions that reach the atmosphere froci cheulcai processed are
generally gaseous and are controlled by incineration, adsorption or absorpMon.
Part leu late emissions may also be a problem, since the psrt T.CU.I-. te-s emitted
are usually e-ctremely small, requiring very efficient treatment for removal,
Emissions data frjm chemical processes arc sparse. It has been, therefore,
frequently necessary to make estimates of emission factoi', on the basis of
material balances, yields or similar processes.
5/83 Chemical Process "industry 3.0-1
-------
5.I ADIPIC A-10
5.1.1 General
Adiplc acid, HOOC (CH: \ COOH, is a will re crystalline solid used in the
iri-'.nu act lire of synthetic fibers, coating^, plastics, urethane foams, elastomers
auu ^ynthr.tic lubricants. ninety percei.t of all adipic acid produced In the
United SLates is used In manufacturing Nylon 6,6. Cyclohexane is the basic
raw material generally useJ to produce adiptc acid, however, one plant uses
eye lohexanone, a byproduct of another process. Phenol has also been used but
has proven to be rore expensive a^.l less readily available than cyclohexatie.
5.1.2 Process Description
L~4
During adlpic acid production, the raw material, cyclohtsxane or
eye lohexanone, Is transferred to a reactor, where it is nxidizcd at 130
to ITO^C (260 - 330°F) to form a cycJohexanol/cyclohexanone mixture. The
mixture is then transferred to a second reactor and la oxidized with nitric
acid and a catalyst (usually a mixture of cupric nitrate and ammonium
nietnvanadate) at 70 to 100°C (160 - 220°F) to form adipic aclJ. Ti.e chemistry
of these reactions is shown below.
0
(a) hNO
H-C C H
21 i '
H9C C H,
" t
H,,
Cyc lohexanune + Nitric acid
HUH
(x)
- COOH
- COOH
(c)H 0
"
-Adipic ac:i'l + 'iitrogen oxides + Water
h,.n - CM. - COOH
«. 1 L
HC - CH - COOH
Cyclriiexancl -*- Ni:;ric acid
-Adipic acid + Nitrogen chides + Water
An alternate rmte fjr synthesizing adipic aoid from cyclohexane (1. C.
Farben process) involves two air oxidation steps: cyclohexane is oxidized to
eye lo.'.exanui and eye lohexanone; eye lohexanone and r.ycloht-xanol are then oxidized
to adipic *scid, with a mixed tiiaugancse/bar ium acetate usc-d a^ the catalyst.
5/F.:
Chemical Process Industry
5. L-l
-------
•
h- '
1
io
n
=^
i •
ID
f
n
ro
ai
3
C-
c
in
n
^
"4
vor
VOC CARBON MONOXIDE
.
* 1
HNOj
VOC MtCVCL
M CCO VERY
1
1 i
f
1 |
CYCLOHEXANE REACTOR _ REACTOR
STORAGF * NO 1 *^" NO 2
t t *
I I
AIR CATALVT NITRIC
ACID
vex:.
PARTICULATE.
MTROGEN OXIDE NITROGEN OXIDE
t J
t NO,
ABSORBER
/ ,
1
CRYSTAL!. IZEM7
-*- STRIPPER ,-*- CENTRIFUGE/
PRODUCT
STILL
f f
1
AIP STEAM
RAWMATFRIAL CYCIOHEXANE NITRIC ACID ADIPICACID
Si"M«ut r "1STIUN REACTION REFINING
PASTICULATE
<
DRYINU,
COOLING
DRYING.
COOLING
PARTICULATE
1
PRODUCT
STORAGE
STORAGE
Figure b. i-i. General Flow diatji^m of adipic acid manufacturing process.
-------
Another possible synthesis method is a direct one stage air oxidation of
cyclohexane to adipic acid with a cobaltoufj acetate catalyst.
The product from the st-cord reactor enters a bleacher, in which the
dissolved nitrogen oxides arts stripped from the adipic acid/nitric acid solution
with air and steam. Various organic acid byproducts, namely acetic acid,
glutaric acid and succinic acid, arc also formed and may be recovered and sold
by some plants.
The adipic acid/nitric acid solution is chilled and sent to a vacuum
crystal lizer.. where auipic acid crystals are formed, tmd the solution is
th<>n centrifuged to separate the crystals. The remaining solution is s^r.t to
another "acuum crysta7lizer, where any residual adipic acid is crystallized
and centrifugally separated. Wet adipic acid from the last crystallization
stage is dried and cooled and then is transferred to a storage bin. The
remaining solution is distilled to recover nitric acid, which is routed back
to the second reactor foi.1 reuse. Figure 5.1-1 presents a general scheme of
the adipic acid manufacturing process.
5.1.3 Emissions and Controls *
Nitrogen oxides (NOX), volatile organic compounds (VOC) and carbon
monoxide (CO) are the major pollutants from adipic acid production. The
cyclohexane reactor is the largest source of CO and VOC, and the nitric ac.*d
reactor is the dominant source of NOX. Drying and cooling of the adipic acid
product create particulate emissions, which are generally low because baghouses
and/or wet scrubbers are employed for maximum product recovery and air pollution
control. Process pumps and valves are potential source> of fugitive VOC
emissions. Secondary emissions occur only from aqueous effluent discharged
from the plant by pipeline to a holding pond. Aqueous eifluent from the
adipic acid manufacturing process contains dibasic organic acids, such as
succlric and glutaric. Since these compounds are not volatile, air emissions
are negligible compared to uther emissions oi VOC from the plant. Figure
5.1-1 shows the points of emission of all process pollutants.
The most rignifleant emissions of VOC and CO come from the cyclohexene
oxidation unit, which is equipped with high and low pressure scrubbers.
S:rubberf have a 90 percent collection efficiency of VOC and are used for
economic reasons, to recov/er expensive volatile organic compounds as well as
for pollution control. Thermal incinerators, flaring am' carbon adsorbers can
all be used to limit VOC emissions from the eyeInhexana oxidation unit with e
greater than 90 percent efficiency. CO boijers control CO emissions with
99.9^ percent efficiency and VOC omissions wivh practically 100 percent efficiency
The combined use of a CO boiler and a pressure scrubber resultr. in nearly
complete VOC and CO control.
Three methods are profit ly used to control emissions f-om the NOX absorber:
water scrubbing, thermal reduction, and flaring -jr combustion in a powerhouse
boi.lsr. Water scrubbris have a low collection efficiency, appro*imately
70 percent, because ot the extensive tlte needed to remove insoluble NO in tht^
absorber offgas stream. Thermal reduction, in which off gases containing NO
are htated to high temperatures and are reacted with excess fuel in a reducing
atmosphere, operates at u^ to 97.5 percerit efficiency and is believed to be
3/83 EMISSION FACTORS 5.1-3
-------
the most effective system of control. Burning off gas In
flaring has an estimated efficiency of 70 percent.
powerhouse or
TABLE 5.1-1.
EMISSION FACTORS FOR ADIPIC ACID MANUFACTURE
EMISSION FACTOR RATING: B
a.
AOlpic
•jartlci
Process
kg/Mg
acid
ill*1 te
Ib/ton
Nitrogen
oxldet"
kg/Mg Ib/ton
Nonmethane
vo Lit lie organic
compounds
k?/Mg Ib/ton
Carbon monoxide
kg/Mg Ib/ton
FLav sjaterlil storage
Uncontrolled
Cy c .Iphexane ox Ida tf on
"Jncooivol led
H/boli«r .
W/there*! incinerator
W/flaringe f
U/carbon absorber
W/»crubber plua. boiler
tiltric acid revet ion
Uncontrolled"
H/waler scrubber
U/rhar,»a] redact loo
U/flaring or coa&ustion
Adlplc acid refining^
Uncoocrollad
Adlplc acid drying, cooling
and storage
0
0
0
0
C.I
P.4
0
0
0
0
0.1'
0.8"
0
c
0
0
0
0
27
B
0.5
a
o.:
53
16
4
16
0.6
1.1
20
Neg
Neg
1
Neg
J
0
0
0
0.3
2.2
40
N«S
Neg
4
2
O.b
56
0.5
Neg
6
58
Neg
1
•teg
12
111
Neg
Reference 1. Factors are in Ib of pc llutant/ton md kg of pollutant/Mg of ad i pic acid produufd.
faN(..g - Negligible.
NOX is In the fora of NO and NO... Althougn large quantities of N ,0 are a Ian produced, N,0 la
.lot a criteria pollutant «nd ls~nut, therefore. Included here.
Fartors are after scrubber processing, ainre hydrocarbon recoverv ualng scrubbers Is an
.Integral pert of edlplc acid manufacturing.
A thermal incinerator ia assumed :o reduce VOC and CO emissions by approximately 99.991.
.A flaring system la assumed to reduce VOC and CO eialssiona by 90Z.
A carbon liborbtr la ansuaed to reduce VOC esUsiiona by 941 and la be ineffective in reducing
CO emlseloa'-,.
^Uncontrolled emission : act or* are after KOX absorber, since nitric ccld recovery it an integral
hpart ot adlp); acid manufacturing.
EsciJiaced 70] control.
^Eatinmted 97.5% -.onr.ro:.
^ Ire lode s chilling, cry, ta 111 eat ion and centr Ifuglng.
ractora are after hJ^house control rlevlce.
i-<+
Chemical Process Industry
5/83
-------
References for Section 5.1
1. Screening Study To Determine Need for Standards of Performance for
New Adipic Acid Plants, EPA Contract No. 68-U2-1316, GCA/Technology
Division, Bedford, MA, July 1976.
2. Kirk-Othmer Encyclopedia of Chemical Technology, ''Adipic Acid", Vol. 1,
2nd Ed, New York, laterscience Encyclopedia, Inc, 1967.
3. M. E. O'Lear", "GEH Marketing Research Report on Adipic Acid",
Chemical Economics Handbook, Stanford Research Institute, Menlo Park, CA,
January 1974.
4. K. Tanaka, "i.uiplc Acid by Single Stage", Hydrocarbon Processing, 55(11) .
November 1974.
5. H. S. Bosdekis, Adipic Acid InCiganic Chemical Manufacturing, Volume 6,
EPA-A50/3-80-028a, U. S. Environmental Protection Agenry, Research Triangle
Park, NC, December 1980.
5/83 EMISSION FACTORS 5.L-5
-------
5.2 SYNTHETIC AMMONIA
5.2.1 General
Anhydrous ammonia is synthesized ^y reacting hydrogen with nitrogen at a
molar ratio of 3:1, then compressing the gu. and cooling it to -33JC. Nitrogen
i3 obtained from the air, while hydrogen is obtained frum either the catalytic
steam reforming of natural gas (methane) or naphrha, ur the electrolysis of
brine at chlorine plants. in the United States, about 98 percent of synthetic
ammonia is produced by catalytic steam reforming of natural gas (Figure 5.2-1).
EMISSIONS DURING
REGENERATION
_ ^
FUEL
EMISSIONS
(PROCESS r*-
CONDENSATE
I
— *- " 1
S It AM
STRIPPER
! 4
STEAM 1
EFFLUENT
FEEDSTOCK
DeSULFURIZATION
*
PRIMARY REFORMER
*
CCfTiWnACrfY RFPHRMPR
*
HIGH TEMPERATURE
SHIFT
LOW TEMPERATURE
SHIFT
*
CO2 ABSORBER
*
MLTHANATION
*
AMMONIA SYNTHESIS
1
MH3
1
FUEL COMBUSTION
EMISSIONS
4
EMISSIONS
f
1
^, RFGFNERATION
A
T
STEAM
PURGE GAS VENTED TO
»" PRIMARY REFORMER
FOR FUEL
\
Figure 5.2-1. General process flow diagram of a typical ammonia plant.
5/83
Chemici1 Process Industry
•5.2-1
-------
Seven process steps are required to produce synthetic ammonia by the
catalytic steam reforml^ method:
Natural gas desulfurization
I'rimary reforming with steam
Secondary reforming with air
Carbon monoxide shift
Carbon dioxide removal
Methanction
Ammonia synthesis
The first, fourth, fifth and sixti steps are to remove Impurities such as
£.jlfur, CO, CO? and water from the feedstock, hydrogen and synthesis gas
streams. In the second titep, hydrogen Js manufactured, and in the third step,
additional hydrogen is manufactured and nitrogen is introduced into the process,
The seventh step produces anhydrous ammonia from the synthetic g.->s. While all
ammonia plants use this basic process, details such r»s pressures, temperatures
and quantities cf ix-eds lock will vary from plant to plant.
5.2.2 Emissions
Pollutants froft the manufacture of synthetic anhydrous ammonia jre en.itted
from four process steps:
Regeneration of the desulfurlzatlon bed
Heating of the primary reformer
Regeneration of carbon dioxide scrubbing solution
Steam stripping of process condensate
More than 95 percent of the ammonia /lants in the U. S. use activated carbon
fortified with metallic oxide additives, for feedstock desulfurization. The
desulfurizatlon bed muut be regenerated ^ibout cnce every 30 days for a 10-hour
period. Vented regeneration steam contains sulfur oxides and/or hydrogen
sulfide, depending on the amount of oxygen in the steam. Regeneration also
emits volatile organic compounds (VOC) and carbon monoxide. The primary
reformer, heated with natural gas or fuel oil, emits the combustion products
NO , CO, SO , VOC and particulates.
Carbon dioxide Is remove^ from the syathesiH gas by scrubbing with
raonoetKanolairine or hot potasaiurn carbonate aolu>.ion. Regeneration of thj~ COo
scrubbing solution with steam produces emissions of VOC, NH3, CO, C02 i^nd
monoe thanolamine.
Cooling the synthesis gas after lew :eraperature shift conversion forms »
condensate containing quantities of NHj, C02, methanol anJ trace metals.
Condensate Kteam strippers are used to removu NH3 and raethanol from the wat^.r,
and steam from th,j is vented to the atmosphere, emitting NHj, C02 and methanol,
5.2-2 EMISSION FACTORS 5/83
-------
Table 5.2-1 presents* tmission factors for the typical ammonia plant.
Control devices are not useO at such plants, so the values in Table 5.2-1
represent uncontrolled emissions.
5.2.3 Controls
Add-on air pollution control devices are not psed at synthetic ammonia
plants, because their emissions are below state standards. Some processes
have been modified to reduce emissions and to improve utility of raw materials
and energy. Some plantj are considering techniques to eliminate emissions
from Che condensate steam stripper, one such being the injection of the
overheads into the reformer stack along with the combustion gases.
TAKI* b 2-1 UNCONTROLLED EMISSION FACTORS FOR 'I5fPICAL AMMONIA PLANT3
EMISSION FACTOR RATING: A
EmlsHion Fol I
Lwsu 1 f ur iza t Ion ur^lt regerera* Ion
Primary re'urner, heatur fuel combustion
Natural gas
Distillate oil
Caroon dioxide regenerator
Condensate steair. strippe*
Pcilluttint
Total 8Llfurc'd
CO
Noiunslhane VOC°
NO
SO
CO"
p^r:ic.ilateg
Me thand
Nomtthanu VCC
NO
so"
cox
P*r ticul lies
Methane
Nvmnwthane VOC
Am^nlj
CO
CO
Nunm« thane VttC
A.'nrronl.l
C3
Nanrae thane VOC"
lg/«g
0.0096
'>.9
3.f
2.7
0.002-
0. iU
0,;i72
0.0063
0.0061
2.7
1.3
0.12
0.45
0.03
0. 19
1.0
1.0
1220
0.52
1.1
3.4
O.h
IS/tor
0.019
1 1. 8
7.2
i.4
0. 00 4 H
0. 136
o. I;A
o.om
O.OIZi
5.;
2. fa
0.24
0.90
0,06
(j.38
2.0
2.J
2"'C
1.04
2.2
6.8
1.2
factors ar<; exp-tused In weight jf entsslonu ,<-r unit we'-aht ,L amnoni.i uroducec.
h,
Intern.:teTt source, avuruge 10 hjurs or.cc ever/ 30 days.
U\irsc caaf js^nmotini, that .ill sulfur vnterln,; tank •!» pit'. .t«d du.-lr.g regenrrH ri0-,.
Noaiailied to i -.^ hour enlislon factor.
t^
Rc't-renre 2.
O.Oi itg/MT (0,1 lo/[on' 1« rM'iocthiir<'Vi
o
•Scvrly methjnol,
5/83
Chemical Process Industry
-------
References for Section 5.2
1. G. D. Raw lings and R. B. Reinik, Sour ceAasessmen t; Sy n t h e 11 c Ammo n i a
production, EPA-6UO/2-77-10/ra, U. S. Environmental Protection Agency,
Research Triangle Park, NC, November 197/.
2. Source Category Survey! Annaonia ManufHCturir.^ Industry, EPA-A50/3-30-014,
U. S. Environmental Protection Agency, Research Triangle Park, NC. August
5.2-4 EMISSION FACTORS 5/83
-------
5.3 CARBON BLACK
5.3.1 Process Description
Carbon black is produced by rhe reaction of a hydrocarbon fuel such us
oil or gas with n limited supply of combustion air .it temperatures of 1370
tc 1540°C (2400 to 28UO°F). The unburned carbon is collected ao an extremely
fine blac'* fluffy particle, 10 to 500 nm diameter. The principal ises of
carbon black are as a reinforcing agent in rubber compounds (especially
tires) and as black pigment in printing inks, surface coatings, paper and
plastics. Two nu»jor processes .ir.'i presently used in the United States to
manufacture catbou black, the nil furnace process and the thermal proc~3s,
The c-il furnace process accuun s for about 90 percent of production, and the
thermal about 10 percent. Two others, tho lamp process for production of
lamp black and the cracking of acetylene to produce acetylene black, are
each used at one plant in the II- S. However, these are small volume specialty
black operations which cons ti Cuv,«i it_-as than 1 percent of total production in
this cr.-jnti.-y. The gas furnace process is being phased out, and the lart
channel black plant in the U. S. was closed ii» 1976.
•1.3.1.1 Oil Furnace Process - In the oil furnace process (Figure 5.3-1 and
Table 5.3-1), an aromatic liquid hydrocarbon feedstock is heated and injected
continuously into the combustion zone of a natural gas fired furnace, where
it is decomposed to form carbon black. Primary quench water cools the gases
to 50U°C (lUOU'F) to stop the cracking. The exhaust gases entraining the
carbon particles are further coo^d to about 230°C (450CF) by passage through
heat exchangers and direct water sprays. The bla"k is then separated from
the gas stream, usually by a fabric filter. A cyclone for primary collection
and particle agglomeration may precede the filter. A single collection
system often serves several manifolded furnaces.
The recovered carbon black is finished to a marketable product by
pulverizing and wet pelletizing to increase bulk density. Water f, OT. the
wet pelietizer is driven off in a gas fired rotary dryer. Oil or process
gas CIP be used. From 35 to 70 percent of the dryer combustion gas is
charged directly to the interior of the dryer, and the remainder acts as an
indirect heat source for the dryer. The dried pellets are then convoyed to
bulk storage. Process yields range from 35 to 65 percent, depending on the
feed composition and the grade of black produced. Furnace designs and
operating conditions determine the particle size and the other rhysicil and
chemical properties of the black. Generally, yields are highest for large
particle blacks and lowest for small particle blacks.
5.3.1.2 Thermal Process - The thermal process is a cyclic operation in
which natural gas is thermally decomposed (ci-^ked) intc carbon particles,
hydrogen and a mixture of other organics. Two furnaces are ustd in normal
ope-ation. The first cracks natural gas and makes carbon black and hydrogen.
The effluent £,as fi'om the first reactor is cooled by water sprays to about
12S°C (250°F), and the black is collected in a fabric filter. The filtered
gas (90 percent hydrogen, 6 percent methane and 4 percent higher hydrocarbons)
5/B3 CUemical Process Industry 5.3-1
-------
w
m
2
5
C/3
C
Z
•*1
>
ft
H
C
90
x
tn
or
ba
OTJHHfHtBUjDMIMHK
311 nOR«Cf TMM
vim c«s
i »T n»s
IBSTDBiCI
-- _ OPIIONAI
OR — •»• a alp
fun on
Figure 5.3-1. Flow diagram for the oil furnace carbon black process.
-------
TABLE 5.3-1. STREAM IUKNTIFICATION FOR THE
OIL FURNACE PROCESS (Figure 5.3-i)
Stream Identification
1 Oil feed
2 Natural gas feed
3 Air to reactor
4 Quench water
5 !\eaclor effluent
6 Gas to oil preheater
7 Water to quench tower
8 Quench tower effluent
9 Bag filter effluent
10 Vent gas purge for dryer fuel
11 Main process vent gas-.
12 Vent gas to Incinerator
13 Incinerator stack gas
14 Recovered carbor. black
15 Carbon black to mlcropulvnrlzet
16 Pneumatic conveyor system
17 Cyclone vent gas recycle
18 Cyclone vent gas
19 Pneuicatic system vent gai-
20 Carbon black from bag filter
21 Carbon black frcm cyclone
22 Surge bin veni
23 Carbon black to pelletizer
24 Water to pelletizer
25 Pelletizer effluent
26 Dryer direct heat source vent
27 Dryer heat exhaust after bag filter
28 Carbon black from dryer bag filter
25 Dryer indirect hea*: source vent
30 Hot gases to dryer
31 Dried carbon black
32 Screened carbon black
33 Carbon black recycle
34 Storage bin vent gus
35 Bagging system vent bas
36 Vacuum cleanup system vent gas
37 Combined dryer virat gas
38 Fugitive emissions
39 Oil storage tank vent gas
Chemical Process Industrv 5.3-3
-------
Is used as a fuel to heat a second reactor. When the first reactor becomes
too cool to crack the natural gas feed, the positions of the reactors are
reversed, and the second reactor is used to crack the gas while the first Is
heated. Normally, more than enough hydrogen is produced to make the thermal
black process self-sustaining, and the surplus hydrogen is usnd to fire
boilers that supply process steam and electric power.
The collected thermal black is pulverized and pelletir.ed to & final
product in much che same manner as is furnace black. Thermal process yield:;
are generally high (35 to 60 percent), but the relatively coarse particles
produced, 180 to 470 nra, do not have the strong reinforcing properties
required for rubber producrs.
5.3.1! Emissions and Controls
5.3.2.1 Oil furnace Procecs - Emissions from carbon black 'nanuficture
include participate matter, carbon monoxide, organics, nitrogen oxides,
sulfur compounds, polycyclic organic matter (POM) and irace eleuents.
The principal source of emissions in the oil furnace process is the
main process vent. The vent stream consists of the reactor effluent and the
quench water vapor vented from the carbon black recovery system. Gaseous
emissions may vary considerably, according to the grade of carbon black
being produced. Organic and CO emissions tend to be higher for small particle
production, corresponding with the lower yields obtained. Sulfur compound
emissions are a function of the feed sulfur r.ontent. Tables 5.3-2 and r>.3-3
show the normal emission ranges to be expected, with typical average values.
The combined dryer vent (stream 37 in figure 5.3-1) emitf carbon black
from the dryer hag filter and contaminants from the usu of the main process
vent gas If the gas is used as a supplementary l:uel for the dvycr. It also
emits contaminants from the combustion of impurities in the natural gas fuel
for the dryer. These contaminants include sulfur oxides, nitrogen oxides,
and the unturned portion of each of the species present in the main process
vent gas (see Table 5.3-2). The oil feedstock storage tanks arc a source of
organic emissions. Carbon black emissions also occur from the; pneumatic
transport system vent, the plantwide va.vaura cleanup system vent, and from
cleaning, spills ard leaks (fugitive emissions).
Gaseous emissions from the main process vent may be controlled with CO
boilers, incinerators or flares. The pellet dryer combustion furnace, which
is, in essence, a i.hercaal incinerator, may also tc employed in a control
system. CO boiler;;, thermal incinerators or co-noinatAons of these devices
can achieve essentr.a^ly complete oxidation of organ ic.-s and can oxidize
sulfur compounds in the process flue gas. Combustion efficiencies of
99.6 percent for hydrogen sulfide and 9;^,8 percent for carbon monoxide have
been measured for a flare on a carbon black plant. Par ticul ate- emissions
may also be reduced by combustion of srnne of the carbon black particles, but
emissions of sulfur dioxide anc nitrogen oxides are thereby increased.
5.3.2.2 Thermal f-jvcess - Emissions from the furnaces in this procass
are very _ow because the offgas is recycled and burned in the next furnace
to provide heat for cracking, or sent to a boiler as fuel. The carbon black
is recovered in a bag filter'bet^een the two furnaces.
5.3-4 EMISSION FACTORS 5/83
-------
The rest ia recycled in the off^as. Some adhere? to the surr'ace of the
checkerbrick where It is burned off in each firing cycle.
Emissions fram the dryer vent, the pneumatic transport system vent, the
vacuum cleanup system vent, arid fugitive sources are similar to those for
the oil furnace process, since the operations which give rise to these
emissions in the two processes are similar. There ia no emission point in
the thermal process which corresponds to thp oil storage tank vents in the
oil furnace process. Also in the thermal process, sulfur compounds, POM,
trace elements and organic compound emissions are negligible, because low
sulfur natural gas is used, md the process offgys is burned as fuel.
TABLE 5.3-2. EMISSION FACTORS TOR CHEMICAL
SUBSTANCES FROM OIL FURNACE CARBON
BUCK MANUFACTURE*
Chemical substance
b
Main process vent gas
kg/Mg Ib/ton
Carbon di*ulfide
Carbonyl sulfide
Me than*
Nonme thane VOC
Acetylene
Ethane
Ethylene
Propylene
Proj-.-ne
Isobutane
n-Bntane
n-Pentane
POM
Tra'-re elements0
30
10
25
(10-60)
45
(5-130)
Oc
1.6
Oc
0.23
0.10
0 27
0C
0.002
<0.25
60
20
50
(20-120)
90
(10-260)
0
3.2
oc
0.46
0.20
0.54
0C
0.004
<0.50
aLxpr>isaed in turms of weight of emissions per unit weight of
.carbon black produced.
These chemical substances are emitted only from the main process
vent. Average- values are based on six sampling runs made at a
represeutatiTS plant (Reference 1). Ranges given in parentheses
are based on results of a survey of operating plants 'Reference 4)
.Below detection limit of 1 ppm.
Beryllium, lead, mercury, among several others.
3/83 Chemical Process Industry 5.3-5
-------
TAHU S.3-3. EMISSION FACTORS
MISSION FACTOR
Ptrtlculati Carbon Monoalaa Nitrogen Uxide*
fliKtu kg/Hg Ib/lon kg/^lg
Oil furnace proctis
Main prcs.a»a vant 3.? 6.53 1,400*
(0.1-5) (0.2-10) (700-2,200)
(I. 2-1.5) (?.*-3) (lOlJ-137)
Ib/ton kg/1g Ib/tun
2,800* 0.2«B O.S/
(1,400-4,400) (1-2.4) (2-5.o)
245 NA NA
(216-274)
rvbined Oryrr vent
Bag fllttrh
Scrubber
Bag filter
Oil «tor»i;« tank v«nt
Uncontrc1 led
syite*
vvnt
Bag fliipr
Fugitive emisalarui
Solid vaflte Incinerator
Thenul proeeoa
0.1?
C.10
C. 12
2.0/
O.it
(0.01-0.40) (0.02-0.80)
0 36 0.71
(O.ul-0.70) (0.02-1.40)
0.2S 0,5o
(0.06-0.70) (0.12-1.40)
0.03 0.06
(U.01-0.05) (0.02-0.10)
0.20
0.24
H.g
0 0"
0.02
Neg
4.61)
0.In 0.73
(0.!2-C.*1) (0.24-1.22)
1.10
2.20
0.04
Unknovr'
Jnkriuwn
Evpicaacd In terns of weight :f caltBlcmk p*2r unit wight of carbon blacK produced. Blanks Iridlcate iio etnlsnlons.
Most plinti LSI tag flltJiB on ill prooiv trilni for product r'cotft-ry except solid uaste Incineration. Some
plants rny use scrubbers on »t least one pi jce«i train. NA. • nit a»allajl«.
Th« partlr.ulate natter is carbon black.
CE«ti»lon factors do not Include organic Julfu- compounds wt Ir.h »r<- reported separately ,1 Table 5.3-2. Individual
orjanlc epe. .PS roaprlsing £h« Toruattna-.s Vv'" 'nloslcn* are Includod In Table 5.3-.2
Average valuta based nn surveya of planta (Reffi 'encaa 4-5).
*Avfr«g> values baaed or. result* at 6 sampling ru:o conducted at a representative plinl vlth a -30un production
rati of 5.1 K 10 1g/yr ('.6 « 10 con/yr). Rang'* of value* arf b^eed on a eurv
-------
FOK CARBON BLACK MANUFACTURE3
RATING: C
Sulfur
kg/Kg
B.f
\J
(U-U)
25
i2 1. 9-2(1)
:?.;
Oxldei
Ib/ton
(0-24J
5U
)5.2
Methane Nonn; thane
kg/Mg Ib/ton kg/Hg
25* 50e 5Ue
C'J-60) (20-120) (10-159)
(1.7-3)
0.99
vocc
lh/ ton
100"
(20-300)
1.7
1.4H
Hydr.igen Sol ( idt
kR/'lg !>>/ton
30- f,C"
ss-n-;8 ioi-2fcsB
i <
o.n o.2^
V.ib 0.5.'
(O.Cl-0.b4) (O.Ob-1.08;
0.20
I).12
0.01 U.02 0.01 0.0!
Keg N»g Sag Kpg Neg
''S la the wilght percent aulfur In fid f«il.
valuei and corresponding ranges uv values die butted on a survey of plant* (Reference *•) and en the
public file* of Louisiana Air Control Comyilaoion.
Eaii»lon factor calculated ui ing toplrlcil corrrlatlona for petrochemical losses (run storage tanks '.vapor
preisure • D.^ kP«J. tmlaaloo* art ooetly aroitvitic olli.
•'Baaed i;n enl««lon rate* obtained tram Che Netlurul Rmiatlont Data Syatea. All plants do rot jae sol'd waa:e
Inelnnratlon. See Srctio' .'.1,
Enlislone from the f^rnac^a are nexllftlble. tmY»slon« f r a the dryer vert, f iei.-i.at ic RyHtera veit i. i vacuuii
cleanup system and '• »ltlve sources are sinlUr to thcaa for the oil furnace proceoa.
Uata .»[•• not available.
Clierolcal Prou«as Industry 5.3-7
-------
References for Section 5.3
1. A. W. Serin and T. W. Hughes, Source Assessment; Carbon Black
Manufacture, EPA-600/2-77-lU7k, U. S. Environmental Protection Agency,
Research Triangle Park, NC, October 1977,
i. Air Pollutant Emission Factors, APTD-0923, U S. Environmental Protection
Agency, Research Triangle Park, NC, April 1970.
3. I. Drogin, "Carbon Black", Journal of theAir Pollution Control
AssociatJ^n, _l_a: 2 16-228, April 1968.
4. Engineering and Cost Study of AirPollution Control forthe
Petrm-hemical Industry, VcK 1:_ Carbon Black Manufacture Lj the
Furnace Process. EPA-450/3-73-006a, U. S. Environmental Protection
Agency, Research Triangle Park, NC, June 19/4.
5. K. C. Hustvedt and L. B. Evans, Standards Supportand Enission Impact
Statement: An Investigation of the Best Sys t mots of Eaiaaion Reduction
for Furnace Proceea Carbon Black PlarUs in theCarbonBlack Industry
(Draft), U. S. Environinent.il Protection Agency, Research Triangle Park,
NC, April 1976.
6. Source Testing of a Waste Heat Boiler, EPA-75-CbK-3, U. S. Environme.ua]
Protection Agency, Research Triangle Park, NC, January 1975.
7. R. W. tiers tie and J. R. Richards, Industrial Process Profiles for
Environmental Use. Chapter A: Carbon Black Industry, FPA-6CO-2-77-023d,
U. S. Environment.il Protection Agency, Cincinnati, OH, February 1977.
8. G. D. P.awlings and T. W. Hughes, "Emission Inventory Data for
Aerylonitrile, Phthalir. Anhydride, Carbon Black, Synthetic Amnrmia,
and Anunoniutfl Nitrate", Proceedings of APCA Specialty Conference on
Emission Factors and Inventories, Anaheim, CA, November 13-16, 1978.
5.3-8 EMISSION FACTORS
-------
S.4 CHARCOAL
5 4.1 Process Description
Charcoal is the solid carbon residue following the pyrolysis
(carbonization or destructive distillation) of carbonaceous raw materials.
Principal raw materials are mediun to dense hardwoods such as beech, birch,
hard maple, hicVory and oak. Others are softwoods (primarily long Leaf and
sl.-sh pine), nutshells, fruit pits, coal, vegetable wastes and paper mill
residues. Charcoal it. used primarily ao 'i fuel for outdoor cooking. In
some Instances, its manufactuxe may be considered as a solid waste disposal
technique. Many raw materials far charcoal manufacture are vastes, as
noted, and charcoal manufacture is also used in forest management for disposal
of refuse.
Recovery of acetic aci^ and methanol byproducts has initially responsible
for stimulation of the charcoal industry. As synthetic production of these
chemicals became commercialized , recovery of acetic acid and methanol became
uneconomical .
Charcoal manufacturing car. be gent rally classified into eitier b
(<«5 percent) or continuous operations '55 percent;. Batch units such as the
Missouri type charcoal kiln (Figure 5.4-1) are small manually loaded md
unloaded kilns producing typically 16 megagraras (17.6 tons) of c^ar;oal
during a thr«ie week cycle. Continuous units (i.e., multiple hearth fun -aces)
produce an average of 2.5 megagrama (2.7S tons) per hour of charcoal.
During the ipj'.iuf acturing process, the wood is heated, driving off water r^nd
highly volatile organic compounds (VUG). Wood temperature rises to approxi-
mately 27S°C (527"7), and VOC distillate yield increases. At this point,
external application ot boat is no longer required, since the carbonization
reactions become exothermic. At 350°C (6S2°F), exothermic pyrolysis ends,
and heat is again applied to remove the less volatile carry materials from
the product charcoal.
Fabrication of briquets from raw material may be either an integral
part of a charcoal producing facility, or an independent, operation, with
charcoal being received as raw inaterial. Charcoal is c.'^hed, mixed with a
binder solution, pressed a..d dried Co produce a briquet ot" approximately
90 percent charcoal.
3-9
5.4.2 Emissions ard Controls
There are five types of charcoal products, charcoal; noncondensible
gases (carbon monoxide, carbon dioxide, methane and eth?ne); pyroacids
(primarily acetic acid and roethanoi)', tars and heavy oils; and water.
Products and product distribution are varied, depending on raw materials and
carbonize t ion parameter;!. The extent to which organlcs nnd carbon monoxide
are naturally combusted before leaving the r«tort varies from pl.-int to
plant. If uncombusted, tars may sulidify to fo-.-m participate emissions, and
pyro.icids may form aero.-:ol emissions.
5/83 Chemic?' Process Industry 5.4-1
-------
I
to
VI
V.
G
\ :"4ift >iw,rj ,
\ L4
IPE STACK]
ROOF VENTILATIQfc
PORTS
AIR PIPES
STEEL DOORS
CONCRETE WALLS
PVIKkYSIS
CASK "
WASTE COOLING AIR
TO ATMOSPHERE
PRODUCT
CHARCOAL
COOLING AND
COMBUSTION AIR
FEED MATERIAL
u.
DO
Figure 5.4-1. The Missouri type charcoal kiln (left) and the multiple hearth furnace (right)
-------
Control of emissions from batch type charcoal kilns is difficult because
of the cyclic nature of the process and, therefore, its emissions. Throughout
a cycle, both the emission composition and flow rate change. Batch kilns do
not typically have emission control devices, but some may use afterburners.
Continuous production of charcoal is more amenable to emission control than
are batch kilns, since emission composition and flow rate are relatively
constant. Afterburning is estimated to reduce emissions of partlculates,
carbon monoxide and VOC by at least 80 percent.
Briquetting operations can control particulate emissions with centrifugal
collection (65 percent control) nr fabric filtration (99 percent control).
Uncontrolled emission factors for the manufacture of charcoal are shown
in Table 5.4-1.
TABLE 5.4-1. UNCONTROLLED EMISSION FACTORS
FOR CHARCOAL MANUFACTURING*
EMISSION FACTOR RATING: C
Pollutant Charcoal Manufacturing Briquetting
kg/Mg Ib/ton kg/Mg lj/ton
Particulattb 133 26>> 28 56
Carbon monoxide0 172 34n
Nitrogen oxides 12 24 - -
VOC
Methane
Nonme thane
52 104
157 314
-
aF.xpressed as weight per unit charcoal produced, Dash - not
applicable. Reference 3. Afterburning Ls estimated to reduce
emissions of particulars, carbon monoxide and VOC>80%. Briquetting
operations can control particulate emission* with centrifugal
.collection (65% control" or fabric filtration (99% control).
'includes t^rs and heavy oils (References !, 5-9). Polycyclic
organic matter (POM) carried by suspended partlculates was deter-
iiuned tc average 4,0 mg/kg (Reference 6).
.References 1. 5, 9.
Reference 3 (Based on 'J.14% wood nitrogen content).
^References 1, 5, 7, 9.
References 1, 3, 5, 7. Consists; of both noncoudensibles (ethane,
formaldehyde, unsaturated hydrocarbons) and cor.densibles (methanol,
acetic acid, pyro^
3/83 Chemical Process Industry ?.4-3
-------
References for Section 5.4
1. Air Pollutant Emissionfactors, APTD-0923, U. S. Environmental Protection
Agency, Research Triangle Par^, NC, April 1970.
2. R N. Shreve, Chemical Procejss^Industries, Third Edition, IcGraw-Hill
Book Company, New York. 1967.
3. C. M. Moscow! tz, Source Asscjsment: Charcoal .^anutac^yr Lng^Statgnf
jhe_ rAr_t_, EPA-600/2-7^-OC4z, U. S. Environmental Protection Agency,
Cincinnati, OH, December 1978.
&. Riegel's Handbook of Industrial Chemistry, Seventh Edition, J. A. Kent,
ed.. Van Nostrand Reinhold Company, New York, 1974.
5. J. R. Hartwig, "Control of Em;scions from Batch-type Charcoal Kilns",
Forest Fi-odu'-tj^ Journal, 2JK9r.'t9-:?U, April 19,'I.
C. W. H. Maxwell, Stationary Source Testing of a Missouri-type CharcoalKiln,
EPA-9U7/9-76-001, U, S. Environmental Protection Agency, Kansas City,
MO, August 1976
7. R. W. "«olke, et al.. Afterburner Systems Study, EPA-RZ-72-062, U. S.
Environmental Protection Agency, Research Triang'.e Park, NC, August
1972.
8. B, F. Keeling, Emission Testing the Missouri-ty^e Charcoal Kilr., Paper
76-37.1, Presented at the C9th Annual Meeting of the Air Pollution
Control Association, Portland, OR, June 197C.
9. P. B. Hulraan, et_ajL., Screening_S_tu^dy on Feasibility oj j^andards of
Performance for Vlood Charcoal Mgnufacturing, EPA Oontnct No. ob-02-2008,
Radian Corporation, Austin, TX, August
5.4-4 EMISSION FACTORS 3/83
-------
CHLOR-ALKALI
S.S.I Process Description'
( hlurine and caustic are produced concurrently by (he electrolysis of brine in eilhet (he diaphragm or mercury
cell. In the diaphragm cell, hydrogen if liberated at the cathode and a diaphragm is used to prevent contact of the
chlorine produced at (he anode with either the alkali hydroxide formed or the hydrogen. In the mercury cell,
liquid mercury is used as the cathode and form} an amalgam with Ihe alkali metal. The amalgam is removed from
the cell a,iJ, is allowed to react with water in a separate chamber, called a denuder, to form the alkali hydroxide
and hydrogen.
Chlorine gas leaving the cell* is saturated with water vapor and Ihen cooled to condense some of the water.
The gjs is further dried by direct contact with strong lulfuric acid. The dry chlorine gas is then compressed for
in-plani use or is cooled furihe. by refrigeration to liquefy the chlorine.
Caustic as produced in a diaphra^n-cell plant leaves the cell at; dilute solution along with unreacted brine.
The solution is evaporated lo increase the concentration to a range of SO lo 73 percent; evaporation also
precipitates most of Ihe residual salt, which is then removed by filtration. In mercury-cell plants, high-purity
caustic can be produced in any desired strength and needs no concentration.
5.5.2 Emissions and Controls1
Emissions from diaphragm- and mercury-cell chlorine plants include chlorine gas, carbon dioxide, carbon
monoxide, and hydrogen. Gaseous chlorine Is present in the blow gas from liquefaction, from vents in tank can
and Unk containers during loading ond unloading, and from storage tanks and process transfer tanks Other
emissions include mere jry vapor from mercury cathode cells and chlorine from compressor seals, header seals,
and Ihe air blowing of depleted brine in mercury-cell plants.
I'hlonne emissions from chlor-alkali plants may be controlled by one of three general methods. (1 I use of the
^js in uthei plant processes, (2) neutralization in alkaline scrubbers, and (3) recovery of chlorine from effluent gas
streams The effect of specific control practices is shown to some extent in the table on emission factors (Table
5.5-1).
References for Section 5.5
1. Atmospheric Emissions from Chlor-Alkjli Manufacture. U.S. EPA, Air Polluliun Control Office. Research
Triangle Park.N.C. Publication Number AP-BO January 1971.
2 Duprey, R.L. Compilation of Air Pollutant Emission Factors. U.S. DHEW PHS. National Cente* fcr Air
Pollution Control. Du'hani, N.C PHS Publication Number 79Q-AP-42. 1968, p. 49.
2/72 Chemical Process Industry 5.5-1
-------
Table 5.5-1. EMISSION FACTORS FOR CHLOR ALKALI PLANTS*
EMISSION FACTOR RATING: B
Type of source
Liquefaction blow gases
Diaphragm cell
Mercury cell*3
Water absorber0
Caustic or lime scrubber0
Loading of chlorine
Tank car vents
Storage lank vents
Air blowing of meirury cell brine
Chlorine gas
lo/lOOtonj
2.000 to 10,000
4.000 to 16,000
25 to 1.000
1
450
1.200
500
kg/1 00 MT
1.000 to 5, 000
2,000 to 8,000
12.5 to 500
0.5
225
600
250
aR«lerino*( 1 and 2.
lotxboui 16 pound! mercury per 100 tori (0.75 kg/100 MT) of chlonne l
5.5-2
EMISSION FACTORS
2/72
-------
5.6 EXPLOSIVES
5.6.1 General
An explosive is e naterial that, under the influence of thermal or
mechanical shock, decomposes rapidly and spontaneously with the evolution of
large amounts of heat and gas. There are two major categories, high
explosives and low explosives. High explosives are further divided into
initiating, or primary, high explosives and secondary high explosives.
Initiating high explosives are very sensitive and are generally used in small
quantities in detonators and percussion caps to set off larger quantities of
secondary high explosives. Secondary high explosives, chiefly nitrates, nitre
compounds and nitramines, are *nuch less sensitive to mechanical or thenral
shock, but they explode with great violence when set off by an initiating
explosive. The chief secondary high explosives manufactured for commercial
and military use are ammonium nitrate blasting agents and 2,4,6,-trinitro-
toluene (TNT). Low explosives, such as black powder and nitrocellulose,
undergo relatively slow autocombustJon when set off _nd evolve large volumes
of gas in a definite and controliat/le manner. Many different types of
explosives are manufactured. As examples of hi&h and low explosives, the
production of TNT and nitrccellulose (NC) are discussed below.
5.6.2 TNT Production1'3*6
TNT may be prepared by either a continuous or a batch process, using
toluene, nitric acid and sulfuric acid as raw materials. The production of
TNT follows the same chemical process, regardless of whether batch or
continuous method is used. The flow chart for TNT production is shown in
Figure 5.6-1. The overall chemical reaction nay be expressed as:
3 + 3HON02 + H2S04- - Y + 3H2° * V°4
Oj
Toioene Nitric Sulfuric TNT Water
/.cid Acid Acid
The production ,)f TNT by nitration of toluene Is a three stage process
performed in a series of reactors, an shown in Figure t>.6-2. The mixed acid
stream is shown to flow counter current to the flow of the organic stream.
Toluene and spent acid fortified with a 60 percent HN03 solution are fed into
the first reactor. The organic layer formed in the first reactor is pumped
into the second reactor, where it IE subjected to further nitration with acid
from the third reactor fortified with additional HN03. The product from the
second nitration step, a mixmre of all possible isomers of «H>. '.trotoluer.e
(DNT), is pumped to the third reactor. 7,i the final reaction, the DNT is
treated with a fresh feed o? nitric acid and oleum (a solution of S03[sulfur
trioxide] in anhydrous sulfuric acid). The crude TNT f~ora this third
nitration consists primarily ov 2,4,6-trinitrotoluene. The crude TNT is
5/83 Chemical Process Industry 5.6-1
-------
c
z
n
H
o
;*>
ro
i
INOX.SOX.
'•OLU'NE.
•TRINITROMETHANE)
TOLUENE
MIXED ACID ""TRATION
•
10MIX
PREPAI
k
RECYCL
L
'
:0 ACID
IATION
•1
SPENT
ACiU
STE
t 1
^_ CRUD'-:
AM
02
t
SPENT ACID
RECOVERY
TMT
RECYCLE
- 93%
H2SO,
PURIFICATION
1
YELLOW
WATER
-ifc.
i
RED
WATER
PURIFIED
TNT
SLURKV
FINISHING
WASTb
AGIO
TO DISPOSAL
I
FtAKE
TNT
NITRIC ACID
CONCENTRUION
TO DISPOSAL TO DISPOSAL TO STORAGE
GASEOUS EMISSIONS
•NEGLIGIBLE AMOUNT
Figure 5.6-1. TNT production
-------
washed t? remove free acid, and the wash water (yellow water) is recycled to
the early nitration stages. The washed TNT Is then neutralized with soda ash
and treated with a 16 percent aqueous sodium sulfite (Sellite) solution to
remove Contaminating isomers. The Sellite waste solution (red water) from the
purification process is discharged directly as a liquid waste stream, is
collected and sold, or is concentrated to a slurry and incinerated. Finally,
the TN") crystals are melted and passed through hot air dryers, where rr.ost of
the wacer is evaporated. The dehydrated product is solidified, and the TNT
flakes packaged for transfer to a storage or loading area.
"OLUENE
SPENT ACID
- *l
1"
NITRO-
TOLUENE
4
OLEUM
t
2nd
NITRATION
ONT
" *
?rd
NiTRATION
^" 1 N 1
PRODUCT
60%HN03 f
97y.HN03
Figure 562. Nitrat on of toluene to form trinitrotoluene.
5.6.3 Nitrocellulose Production
1,6
N1 frocel lul->sfc is commonly prepared by tne batch type mechanical dipper
process. A newly developed continuous nitration processing method is also
being used. In batch prod-jc tio<>., cellulose ir 'he form of cotton linters,
fibers or specially prepare:.! v/ood pulp is puriiied by boiling and bleaching.
The dry and purified cotton linters or wood pulp are added to mixe:l nitric ari
•iulfuric acid in metal reaction vessels known as dipping pots. The reaction
is represented by:
) * 3HON0 * U-(CU (ONO) + 30 * ISO
Cellulose Nitric Sulfuric Nitrocellulose
Acid Acid
Water
Sulfuric
Acid
Following nitration, the crude NC is centrifu^ed to remove most of the spent
ni tr* ti".g acids and is put through a series of water washing and boiling
treatments to ;.ju"ify the final product.
TABLE '...6-1. EMISSION FACTORS TOR THE OPcN BURMINC OF
(Ib pollution/ton TNT burned;
a,b
Type of
Eiploilvi
TNT
VoUtll*
^'articulates Nitrogen Carbon Organ J.c
Oxide* Monoxide C impounds
KJO.O
liO.O
56.0
1.1
Reference 7. Particul«ie enlBiioiu *re Root. VOC i* nonv-«th«ne.
The burns «er« nade on \ery amall quantitiee of TNT, with I«B'.
apoaratu« designed to ainulate open burning c^ndltlcrit. Slr.-i1
•ucK teat «lnul«tlon» can never replicate actual cpeii burning, it
IB (idvleab)e to uae the factors in this Table with caution.
5/83
Process Industry
5.6-3
-------
TABLK 5.6-2. EMISSION FACTORS FOR
EMISSION FACTOR
FTocaia
Part Icul
Ib/lon
Sul fur oAldes
(SUJ
llj/lon
TNT - Batch Proceaa
N) tratlun rcac-fjr*
Funtf rtft iwery
Acid mcuvvry
Nitric acid cencantratori.
S-jlfurlc acid corcenfratort
tl-ctro. title
preclpjitor \exlt)
Electrostatic preclpl taior
v, ac"
Red water Incinerator
I'ncoulr ul 1 *d
Uai jcruLihar*
S«lllt«
TNT - Contlnuoui I .'jcase
Nitration reactor*
FUM recovery
Acid recovery
R«d water incln«rati^r
Nitroctl K luae
Miration reactors
Nitric acid conc*n t »•* tor.
Sulfurlc acid concunt r.t tor
Boll'ng tubs
(U.Olb - 63)
0.4
(O.J3
1
o.n
(U.U1S - U.2S)
(J.U3 - O.b)
(2 - 20)
I
(U.UZb - 1. ib)
1
(O.O.Z5 - 1.75)
29.5
(O.C05 - 88}
0. 12
(0.025 - 0.22)
(0.4 - I)
3d
14
('i - 40)
(0.05 - 1.5)
(O.Cl - 177)
0.24
(O.C5 - <).4
(0.4-13S)
For son* pructM*e», conilderabla varidtlun* In tfiiljalcn. have been reported. nvurage of reported values
iti shown flrnt, ranges In parenthieaifs. rfl *rv. unly eric r.u?ib«r Is ^Iven, jnly ono ^ourct.' to^t ^.MS
avallahla. Fnls-mon factory are in unlta ol Icj of i.ollut.tnt per Hg anrt ;xnincs of po'> l-.it.«.it p« r t. n of TNi
ur Nl troc*1. IU'OSB producaxj.
Significant er^isfllonB of volatile organic co«pri.ndb have ui'L been repurt\;i1 tor *liil cup l-is Ives irif'i.st'-y.
Ucyaver, negligible emissions of toluene and tr In t tro'ae thane (TNP) froTi nL'racion
reactors have bten oported In TNT manufacture, A]»u, (uijltlve VUC emlastcns nay r-sul t fr pn
varioui solvent rrrovfry operarlonit. See KefvrencK h.
isi >!t1d(Uon>i influcncei* h> niirubody l«vel>i and ty,>e of furn.ic^ furl.
data ^va;laDle for NO emissions af.er ncrubber. NO eml!*-* U>ns ace Jasi.ne
EMISSION FACTORS
S/P.'-!
-------
EXPLOSIVES MANUFACTURING**b
RATING: C
Nlcrog«n oxldtii KiCrle acid nisi Sulfurlc acli' mist
(NU,> ;ioot UNO j (iou>. H..SO >
*•&/*» ' Ib/lon kji/Mjj In/ to.-, kit/ton Th/«cn
(J -
2;.
(0.5
Id.
(J -
21
(1 -
2U
(i -
5 25 0.5 I
\9) (.6 - 3d) (U.l> 0.*5) (C.3 - 1.9)
5 55 so 91
- It) (\ - 136) (0.005 - 137) (O..J2 - 275)
< 3!
36) 1.16 - 12)
-.0
1.1.') U - 6C)
MJ — —
40) (2 - 8U)
— —
4.5 S
(0.15 - 1 1,3) (0."'
j2.5 65
(0.5-94) (1 -
2.5 5
(2 - J/ (4 -
- 27)
Ida;
6)
26
(l.c. - 101)
f.
(r.* - 16)
4 8 0.5 !
(3.35 - 5) (6.) - 10) (0.15 - 0.»5 (0.3 - 1.9)
1.5 3 0.01 O.U2
(0.5 - 2.25) (1 - 'i.5) ((.i.005 - 3.015) (0.0! - 0.03;
1.1 7
(3 - '" d«i partlcolatf after curirol m noi he <;igrll ICARI , hff.'.i
*'" pruduT* with iov -ilirugen . .:n:^nt (WX), ni:tj 1'ifc^ cnj of r;n\f,r. ?.jr ,ir.;.'Mct^ wi fi
r..lTL3^*«T cor.t«n(. •ij') lower *-nd uf r.m^e.
5/83 CheiriJcal Process Industry 5.6-5
-------
°-3 3-7
;.f>.4 Emissions and Controls" *
Oxides of nitrogen (NUX) and sulfur (5(,'x) a •:•• the ma ji- c emissions f.'om
the processes involving the manufacture, concentration and recovery of acids
in the nitration process of explosives inanuf »c Curing. Knission.s from (.!,«-
manufacture of nitric and sulfurLc acid ar" discu sed in oth./r Section',- of
this publication. Trini irome thane (T.vfM) is a fasoms byproduct of the
nitration process of TNT Man''*" - • ture. Voi.Hti.ie organic compound smiss'.ons
result primarily from fugitive vapors frnn various solvent recu.'erv
operations. Explosive wastes ,ind co .f ani.ua ted p^cV.igir,^ 'nateri.il .ire
regularly disposed of by open burning, rnd such results in nncont rol 1 ,H
emissions, mainly of NO x and particul.it:: matter. F.xp^r tnenr \\ burns of
several explosives to deic-T.iiii; "typic/,1" ei-.i^s L...n f u tors for the rson
burning of TNT aru prestuied in Table 5.fi-l,
In tiie manufHCture of TN'l , emissions from r!u- nitrators conr,»:ai;ig NO,
NOT, N2U, trinitromethane (TNV.) and sjrae tolien'J .»re parsed throuy;i .1 fuiie
recovery system to extract NOX as nitric act,', .ind then are vt-nt^-! through
scrubbers to ':hi atnospliere , Final emissions contaii qudntLtios of unabsorbed
NOX and TNM. Kmissions may also cotrc from tin- production of Scllite solution
and the incineration of red water. Red wat;-;r incinerntion results in
atmospheric emissions of Nl) , SO aid ash (pri-narily Na.,S'j/t)
In the inanuf a^ tur<_j of nitrocellulose, emissions from rea<;i.or puts ,ind
centrifuge are vented to an NOX waCer dbsorber. The weak UNl \ solutioa is
transferred to the acid concentration system. Absorber tjmisiiops jrc ^aiiily
NOX. Another possible source of emissions is the lioilinj; t'.hs-, where steam
and acid vapors vent to the absorjtr.
The most important fact riffle tiny nmissioivj fr<;-n exp1 osl'-es inanuf .ic tur«?
is the type and efficiency of tilt manuf ac • irin^ process The eFficiency of
the ncid und fume recovery syst^ns f'ir TNT inanut ac ture w.ll di IVM- .-. iy affect
the atmospheric emissions. In addition, th<; de^.'e^ t:) tnicii acids .jfi1 L'Xposo-J;
to the atmosphere during the manaf ac tur i iy process jffH'.-t* the N'0X am: SOX
tmissinns. For nitrocellulose production, enissijnv nro inf luu'i'CC-J; by L:,o
nitrogei content and the desired product quality. 'jper.it ing conditions ,;i 1 I
also affect emissions. Both TNT and n,'. t rocel 1 ul ose cr.n he produce^ in hitch
proces&esi Such processes may nevi"- reach scr?;idy st^t^, .ind I'-nissi.ni
concentrations may vary considerably wit'i time, anil " 1 ii<; tua t io.is in fir Lss iims
will inrlijtmce the efficiency of control met'iods.
Sevetal measures may hi? taken to rt'ducc* e'riss.ons fr^^i I'X-.i losive
manufacturing. The effects of various control dt.-vice--, and process cbiJi^ ;<•"-;,
.•ilnn^; with enissinn factors f<.r t'X,ilosives .n.i"uf ar t'iri ny, ire .-shown in
Table 5.6-2. The emission favt.'rs are .'1! rel.itnd in the a:tiouiit >f product
produced and are appropriate e'tlier for e-itinHtin^ ^(ng tf*rn e:ni si:; i'>n-« or for
evaluating plant operation ;p^r.H t j n,-; schedul i.'S, t'u i"iis;]v)n
.. 6-6 i-.-VISSIiiN KAi'l'DKS
-------
factors in Table 5.6-2 should bt used with caution, because processes no*.
associated with the nitration step are often not in operation at the same time
as the nitration realtor.
References for Section 5.6
1. R. H. Shreve, Chemical Pro-ess Industries. 3rd Ed., McGraw-Hill Book
Company, New Yo"lt, 1967.
2. Unpublished data on emissions from explosives manufacturing, Office of
Criteria and Standards, National Air Pollution Control Administration,
Durham, NC, June 19/U.
3. F. B. Hlggins, Jr., et al., "Control of Air Pollution From TNT
Manufacturing", Presented <>t 60th annual meeting of Air Pollution Control
Association, Cleveland, Oh'. June 1967.
4. Air Pollution Engineering Source Sampling Surveys, Radford Army
Ammunition Plant, U. ;', Army Environmental Hygiene Agency, Edgewood
\rsenal, MD, July 1967. July 1968.
5. Air Pollution Engineering Source Sampling Surveys, Volunteer Army
Amraunicion Plant and .Joliet Army Ammunition Plant, U. S. Army Environmental
Hygiene Agency, Edgewood Arsenal, MT), July 1967, July 1968.
6. Industrial Process Profiles for Environmental Use: The Explosives Industry,
EPA-600/2-77-0231, U. S. EiAironmentol Protection Agency, Research Triangle
Park, NC, February 1977.
7. Specific Air Pollujantsfiom Munitions Processing a.nj. Their Atmospheric
Behavior, Volume 4; Open Si-ming and Incineratioii of Wiste Munit^ions,
Rpscarch Triangle Institute, Research Triangle Park, NC, January 1973.
5/83
Cl.i:ir.ice»i Process Industry 5.6-7
-------
5.7 HYDROCHLORIC ACID
HydiodilorU jcid is r.uinufuctured by 2 numbei of dilTeieH chemical processes. Approximately 80 percent of
(he hydrochloric acid, however, is prndiued by tlie by-product hydrogen chloride process, which will be the only
process discussed in this section. Tn<; synthesis process and !hc Mannheim process arc of secondary importance.
v7.1 Process Description1
Hy-product hydrogen chloride is produced when cMorinc is added to an organic compound such as benzene.
toluene, and vinyl chloride Hydrcchioiic acid is i.^lij,; J js a by-product of this reaction. An example of a
pro.ess that generates hyJrochlunc ac'd as a bypro:1u<'i ii the direct chlorination uf benzene. In (his process
ben '.enc, chlorine, hydn.gen, air, and some tnce catalysis are the raw materials that produce chlororxnzene. The
gjses from the reaction of benzene and chlorine consist. Of hydrogen chloride, benzene, chlorob'Muenes, and air.
These uses nre firs) scrubbed in J pacKed lower witn a chilled mixture of monochlorobenzenc and
dichlorubenzenc to uondensc and recover any berucne or chlornbcnzene The hydrogen chloride is then absorbed
in a falling film absorption plant.
5.7.2 Emissions
The ;ccovery of the hydrogen chloride from the chlorination of an organic compound is the major source of
hyi|-o|ien chloride emissions. The exit gas from the absorption or scrubbing system is the actual source of the
hydrogen chloride emitted. Emission factors for hydrochloric acid produced as by-product hvdrogen chloride arc
pre»LMiied in Table 5.7-1.
Table 5.7-1 EMISSION FACTORS FOR HYDROCHLORIC
ACID MANUFACTURING1
EMISSION FACTOR RATING: B
Hydrogen chloride emissions
Typo of process
By-product hydrogen chloride
With final scrubber
vVitho-jt final scrubbei
Ib/tcn
kg/MT
1 • ~ •
0.2
3
0,1
l.b
Reference Tor Section 5.7
I. Atmospheric bmissions from Hydrochloric Acid Manufacturing Processes. U.S. DHEW, PHS, CPEHS,
Na»" mal Air Pollution Control Administration. Durham. N.C. Publication Number AP-54. September !9( P.
2'72 Chemical Process Industry 5.7-1
-------
5.8 HYDROFLUORIC ACID
1-3
5.8.1 Process Description
Nearly all of the hydrofluoric acid, or hydrogen fluoride, currently
produced in the United States is manufactured by the reaction of acid-
grade fluorospar with sulfuric acid in the reaction:
CaFj + H2SOi, > CaSO^, + 2 HF
Calcium Sulfuric Calcium Hydrogen
Fluoride Acid Sulfate Fluoride
(Fluorospar) (Anhydrite) (Hydrofluoric
Acid)
The fluorospar typically contains 97.5 percent or mere calcium fluoride,
1 percent cr less silicon dioxide (S102), and 0.05 percent or less
sulfur, with ualci'im carbonate (CaC03) at* the principal, remainder. See
Figure 5.8-1 for a typical process flow diagram.
The reaction to produce the acid is encothermic and i-? usually
carried out in externally heated horizontal rotary kilns for 30 to 60
minutes at 390 to 480°F (200-25G°C). Dry fluorospar and a slight excess
of sulfuric acid are fed continuously to the front end of the kiln.
Anhydrite is removed through an air lock at the opposite end. The
gaseous reaction products - hydrogen fluoride, excess sulfuric acid from
che primary reaction, silicon tetrafluor.lrte, sulfur dioxide, carbon
dioxide, and water produced in secondary reactions - are removed from
the front end of the kiln vith entrained particulate materials. The
particulates are removed from the gas stream by a dust separator, and
the sulfuric acid and water are r.etnoved by a prec^ndenser. The hydrogen
fluoride vepors are condensed in refrigerant condensers and are delivered
to an intermediat- ttorage tank. The uncondensed gases are passed
through a sulfuric acid absorption tower to remove nost of the remaining
hydrogen fli'oride, which is also delivered with the residua] sulfuric
acid to the intermediate storage tank. The remaining gases are passed
through water scrubbers, where the silicon tetrafluoride and remaining
hydrogen fluoride are recovered as fluosilicic acid (^SiF^). Th«?
hydrogen fluoride and sulfuric acid arr delivered to distillation
columns, where the hydrofluoric acid is extracted at 99.98 percent
ourl y. Weaker concentrations (typically 70-80 percent) are prepared by
dilution vith water.
1 2 k
5.8.2 Emissions and Controls ' '
Air polluting emissions are suppressed to a great extent by the
condensing, scrubbing ana absorption equipment used in the recovery and
purification of the hydrofluoric and flucsllicic acid products. Partic-
ulate iraterinl in the process gas stream is controlled hy a iiust separator
near the outlet of the kiln aid is recycled to the kiln for further
-------
Figure 5.3-1. Process flow diagram of a typical hydrofluoric acid plant.
•f.
X
X
PAKTICIILATES
SPAR
STORAGE
SILO
PARTlCt'LATES
DRYCNO KI1.N
AClr
SCRUOBER
^
t
DUST
SEPARA-
TOR
ItF
S1F,,
S02
nOTAHY
KiLH
PARTIOJIJiTES
SPAR
USE
SILO
CONDENSERS
1
PiUHClPAL EMISSION LOCATIONS
»i<
INTk'KMCOIATE
STORAGE
AC in
SCRUBBER
._T
iLJ
H?0
CAUSTIC
WATER
SCRUBBER
SCRUB
WATER
SCHUBBER
ER
MF
SIPi,
I | . | » VENT
| »*4| U| (TAIL GAS)
mi oj
rn
30-35Z H2SiFE
1'HODUCl' STOMCE
99.9S2 ll¥
PBODUCT STOllACE
DESORBER
STILL
-------
Table 5.8-1. EMISSION FACTORS FOR HYDROFLUORIC ACID MANUFACTURE
Type of Operation
and Control
j - a
i'^ar drying
Uncontrolled
Fabiic li.'.ter
Spar handlJng
silosb
Uncontrolled
Fabric filter
Transfer operations
jnconr "ol led
Covers, additives
Tail gasC
Uncontr-jl led
(•.-.••'-' J^ ± — "*•*• = [
Control
efficiency
«)
0
99
Q
W
0
80
0
99
Emissions
Cases
Ib/tor. acid
25.0 (HF)
30.0 (SiF,J
45.0 (S02)
0.2 (HF)
0.3 (S1FO
0.5 (S02)
kg/HT acid
12.5 (HF)
15.0 (SiFiJ
22.5 (S02)
0.] (HF)
0.2 (SUO
0.3 (SOZ)
Particulars (Spar)
Ib/ton
F] uo ro spar
•'S.O
0.8
60.0
0.6
6.0
1.2
kg/OT
Fluorospar
37.5
0.4
30.0
0.3
3.0
0.6
Emission
Factor
Rating
C
D
E
D
Riterenci 1. Averaged from information provided by four plants. Hourly fluorospar input calculated
from reported 1975 vear capacity, assuming stoicMrjmefric amount of calcium fluoride and 97.32
contp.it in fluorospar. Hourly emission rates calculated from reported bnghouse controlled rates.
Values averaged were:
Plant 1975 capacity Emissions Ib/Toil Fiuorospar
106
130
42
30
Informt-t i-j,i as j":i NoLu a, Koi.r plants averaged for silo emissions, two pl;i«it« fcr transfer operations
emissions.
Information as in Nore a. Three plants --iveraged. Hf and Si'\ emission factors verified hy infnrmntion
in Reference 4.
1
2
3
i-t
lt
2J
50
11
,000
,UOO
,000
,000
ton HF
ton HF
ton HF
ton HF
-------
processing. The precondenser removes water vapor and sulfuric acid
mist, and the condenser, acid scrubber and water scrubbers remove all
but small amounts of hydrogen fluoride, silicon tetrafluoride, sulfur
dioxide and carbon dioxide from tho tall gas. A caustic scrubber is
employed to reduce further ;.he levels of these pollutants in the tail
gas.
Dust emissions result from the handling and drying of the fluorospar,
and they are controlled with bag filters at the spar storage silos and
drying kilns, thf.J.r principal emission points.
Hydrogen fluoride emissions are minimized by maintaining n slight
negative pressure in the kiln during normal operations. 'T-iJer upset
conditions, a standby caustic scrubber or a bypass to thr toil gas
caustic scrubber are used to concrol hydrogen fluoride emissions fnm
the kiln.
Fugitive dust emissions from spai handling and storage are con-
trolled with flexible coverings and chemical additives.
Table 5.8-1 lists the emission factors for the various process
operations. The principal emission locations are shown in the process
flow tliagram, Figure 5,8-1.
References for Section 5.8
1. Screening Study on Feasibility of Standardsof Performance for
Hydrofluoric Acid Manufacture. EPA--450/3-78-109, U.S. Environmental
Protection Agency, Research Triangle Pa:V., NCr October 1978.
2. "Hydrofluoric Acid", Kirk-Othmer Encyclopedia of Chqaicgl
Technology, Vol. 9, Inte.rscieuce Publishers, New York, 1965.
3. W. R. Rogers and K. Muller, "Hydrofluoric Acid He .ufacture",
Chemical Engir.fefe-ring Progree^, 52^5^:65-8, May 1963.
A. J. M. Robinson, BL al.. Engineering and Cost Effectiveness Study
of yiuoridp Etiissions Cciitrol, Vcl. 1, PE 207 506, National Technical
Information Service, Springfield, VA, 1972.
EMISSION FACTORS 2/80
-------
5.9 NITRIC ACID
5.9.1 Process Description
Weak Acid Production - Nearly all the nitric acid produced in tne
United States is manufactured by the catalytic oxidation of ammonia
(Figure 5.9-1). This process typically consists of three steps, each of
which corresponds to a distinct chemical reaction. First, a j.;9 ammonia/
air mixture is oxidized at high temperature (1380 - 1A70°F or
750 - 800°C) as it passes through a platinum/rhodium catalyst, according
to the reaction:
4NH3 + 502 * 4NO + 6H20 (1)
Ammonia Oxygen Nitric Water
oxide
Alter the process stream is cooled ro 100"F (38°C) or leas by passage
through a cooler/condenser, the nitric oxide reacts with residual oxygen
to focra liitrogen dioxide:
2NO + 02 -> 2N02 +
Nitrogen ~* Nitrogen (2)
dioxide terroxide
Finally, the gases are introduced into a bubble cap plate absorption
column for contact with a countercurrent stream of water. The exothermic
reation that occurs Is:
3N02 + H20 + 2HN03 4 NO (3)
The production of nitric oxide in Reaction 3 necessitates the intro-
duction of a secondary air stream into the column to oxidize it into
nitroger dioxide , thereby perpetuating the absorption opera "ion.
In the p'ist, nitric acid plan's have been operated at a single
pressure, ranging from 14-7 to 176 pounds per square inch (,100 - 1200 kPa),
However, since Reaction 1 is favored by low pressures and Reactions 2
and 3 are favored by higher pressures, newer plants tend to be operating
two pressure systems, incorporating a compressor betvaen the oxidizer
and the condenser.
The spent gai flov;s from the top of the absorption tower to an
entrainm at separator for acid mist removal, chrough p heat exchanger in
thr ammonia oxidation unit for energy absorption by the ammonia stream,
through an expander for energy recovery, and finally to the stack. In
most plants, however, the tail gas Is treated to remove residual nitrogen
oxides before release to the ttroosphere.
High Strength Acid Production - Th?. nicric acid concentration
process consists of feeding strou? sulfuric acid find 50 - 70 percent
nitric acid to the top of a peeked dehydrating column At approximately
atmospheric pressure. The acid mixture flows downward counter to ascend-
ing vapors. Concentrated nitric acid leaves the top of the column as 98
10/80 Cnamic.il Process Industry 5.9-1
-------
AIR
EMISSION 1
POINT f
COMPRESSOR
EXPANDER
EFFLUENT
STACK
I— -NOX EMISSIONS —
I CONTROL
CATALYTIC REDUCTION
WASTE
HF.AT
BOILER
ENTRAINED
MIST
SEPARATOR
PLATINUM
FILTER
NITRIC
ACID GAS
SECONDARY AIR
c
AS
i
T
AIR
(COOLING
f WATER
)
C
c
-
L^.
ABSORPTION
TOWER
— —
COOLER
CONDENSER
NO?
PRODUCT
(SO • 70%
HN03)
Figure 5.9-1. Flow diagrcm of typica' nitric ricid plant using pressure process (high strength
acid unit not shown).
5.9-2
EMISSION FACTORS
10/80
-------
percent vapor, containing a small amount of N02 and 02 from dissociation
of nitric acid. The concentrated acid vapor leaves the colunm and goes
to a bleacher 3nd countercurrent condenser system to effect the conden-
sation of strong nitric acid and the separation of oxygen and nitrogen
oxide byproducts. These byproducts then flow to an absorption column
where the nitric oxide mixes with auxiliary air to form N02, v;hich Is
recovered as weak nitric acid. Unreacted gases are vented to the atmo-
sphere from the top of the absorption column.
TABLE 5.9-1. NITROGEN OXIDE EMISSIONS FROM NITRIC ACID PLANTS3
EMISSION FACTOR RATING: B
Control Emissions
Source Efficiency. % Ib/ton Acid kg/MT Acid
Weak Acid Plant Tail Gas
0
(14 - 86) (7 - 43)
Uncontrolled1* 0 43 22
Catalytic reduction
Natural gasb 99.1 0.4 0.2
(0.05 - 1.2) (0.03 - 0.6)
Hydrogen0 97 - 99.B 0.8 0.4
(0 - 1.5) (0 - 0.8)
Natural gas/hydrogen
(,25%//5X) 98 - 98.5 1.0 0.5
(0.8 - 1.1) (0.4 - 0.6)
Extended absorption 95.8 1.8 0.9
(0.8 - 2.7) (0.4 - 1.4)
High Streng.h Acid Plant6 NAf 10 5
aBased on 100% acid. Production rates are In terms of total weight of
product (water and acid). A plant producing 500 tons (4"4 MT)/day of
55 wt. % nitric acid is calculated as producing 275 tons (250 MT)/day
of 100% acid. Ranges in parentheses. NA: Not Applicable.
Reference 3. Bastd on a study of 18 plants.
^'References 1 and 2. Based on data from 2 plants with these process
conditions: production rate, 130 tons (118 MT)/day at 100% rated
capacity; absorber exit temperature, 90°y (32°C); absorber exit
pressure, 87 psig (600 kFa) •, acid strength, 57%.
References 1 and 2. Based on data from 2 plants with these process
conditions: production rate, 208 tons (188 MT)/day at 100% rated
capacity; absorber exit temperature, 90°F (32"C); ab-wrber *»xit
presure. 80 psig (550 kPa); acid strength, 57%.
References 1 and 2. Ban«d on a unit that produces 3000 Ib/hr (6615
kg/hr) at 100% rated capacity, of 98% nir-lc acid.
10/80 Chemical Process Industry 5.<*-3
-------
The two most common techniques used to control absorption tower
tail gas emissions are extended absorption and catalytic reduction. The
extended absorption technique reduces emissions by increasing the effi-
ciency of the absorption tower. This efficiency increase is achieved hv
Increasing the number of absorber trays, operating the absorber at
higher pressures, or cooling the weak acid liquid In the absorber.
In the catalytic reduction process (often termed catalytic oxidation),
tall gases are heated to ignition temperature, mixed with fuel (natural
gas, hydrogen, carbon monoxide or ammonia) and passed over a catalyst.
In the presence of the catalyst, the fuels are oxidized, and the nitrogen
oxides are reduced to N2- T"e extent of reduction of NG2 and NO to N2
is a function of plant design, fuel type operating temperature and
pressure, space velocity through the reduction catalytic reactor, type
of catalyst, and reactant concentration. See Table 5.9-1.
Two seldom used alternative control devices for absorber tail gas
are molecular sieves and vet scrubbers. In the molecular sieve technique,
call gas is contacted with an active molecular sieve which catalyticly
oxidizes NO to NO9 and selectively adsorbs the -J02. The N02 is then
thermally stripped from the noleculat sieve and returned to the absorber.
In the scrubbing technique, absorber tail gas is scrubbed with an aqueous
solution of alkali hydroxides or carbonates, ammonia, urea or potassium
permanganate. The NO and N02 are absorbed and recovered as nitrate or
nitrite salts.
Comparatively small amounts ot nitrogen oxides are also loat from
acid concentrating plants. These Icsses (mostly N02) are from the
condenser system, but the emissions are small enough to be controlled
easily by Inexpensive absorbers.
Acid mist emissions do not occur from the tail gas of a properly
operated plant. The small amounts that may be present- in the absorber
exit gas streams are removed by a separator or collector prior to entering
thy catalytic reduction unit or expander.
Emissions from acid storage tanks may occur during tank filling.
The displaced gases are equal In volume to the quantity of acid added to
the tanks.
Nitrogen oxide emissions (expressed as N02) are presented for weak
nitric acid plants in Table 5.9-1. The emission factors vary consider-
ably with the type of control employed and with process conditions. For
comparison purposes, the EPA New Source Performance Standard for both
new and modified plants is 3.0 pounds per ton (1.5 kg/MT) of 100 percent
acid produced, maximum 3 hour .Average, expressed as Nr>2 •
5.9-4 EMISSION FACTORS 10/80
-------
5.9.2 Eaisaions and Controls
Emissions from nitric acid manufacture consist primarily of nitric
oxide, nitrogen dioxide (which accounts for visible emissions) and trace
amounts of nitric add mist. By far, the major source of nitrogen
oxides is the tail gas from the acid absorption tower (Table 5.9-1). In
general, the quantity of NOy emicsicns is directly related to the
kinetics of the nitric acid formaticn reaction and absorption tower
design.
The two most common techniques used to control absorption tower
tail gas emissions are extended rbsorption and catalytic reduction. The
extended absorption technique reduces emissions by increasing the effi-
ciency of the absorption tower. Thic efficiency increase is achieved by
Increasing the number of absorber trays, operating the absorber at
higher pressures, or cooling the weak acid liquid in the absorber.
In the catalytic reduction process (often termed catalytic o-cidatlcn),
tall gases are heated to ignition temperature, mixed with fuel (natural
gas, hydrogen, carbon monoxide or ammonia) and passed over a catalyst.
In the presence of the catalyst, the fuele are oxidized, and the nitrogen
oxides are reduced to N2. The extent of reduction of NO? and NO to N2
Is a function of plant design, fuel type operating temperature arc!
pressure, space velocity through the reduction catalytic reactor, type
of catalyst, and reactant concentration. See Table 5.9-1.
Two seldom used alternative control devices for absorber tall gas
are molecular sieves and wet scrubbers. In the molecular sieve technique,
tail gas IP contacted with an active molecular sieve which r.atalyticly
oxidizes NO to N02 and selectively adsorbs the N02. The NO2 is then
thermally stripped from the molecular sieve and returned to the absorber.
In the scrubbing technique, absorber tail gas is scrubbed with an aqueous
solution of alkali hydroxides or carbonates, ammonia, urea or potassium
permanganate. The NO and N02 are absorbed and recovered as nitrate or
nitrite salts.
Comparatively small amounts of nitrogen oxides are also lost from
acid concentrating plants. These losses (mostly N02) are from the
condenser system, but the emissions are small enough to be controlled
easily by inexpensive absorbers.
Acid mist emissions do not occur from the tail gas of a properly
operated plant. The snail amounts that may be present in the absorber
exit gas streams are removed by a separator or collector prior to entering
the catalytic reduction unit or expander.
Emissions from icid storage t-nks may occur during tank filling.
The displaced gases are equal in voluira to the quantity of acid added to
the tanks.
Nitrogen oxide emissions (expressed as N02) are presented for weak
nitric acid plartzs in Table 5.9-1. The emission factors vary consider-
ably with the type oi control employed and with process conditions. For
comparison purposes, tu^. EPA New Source Performance Standard for both
10/80 ChtTiical ?rocess Industry 5.9-5
-------
new and modified planes la 3.0 pounds per con (1.5 kg/MT) o' 100 percent
acid produced, naximun 3 hour average, expressed as NOa.
References for Section 5.9
1. Control of Mr Pollutionfton Nitric Acid Plants. Office of Air
Quality Planning and Standards, U.S. Environmental Protection
Agency, Research Triangle Park, NC, August 1971. Unpublished.
2. AtmosphericEmissions from Nitric Acid Manufacturiag Processes.
999-AP-27, U.S. Department of Health, Education and Welfare,
Cincinnati, OH, 1966.
3. Marvin Drabkdn, A Review of Standards of Performance for New
Stationary Sources - NUric Acid Plants. EPA-450/3-79-013, U.S.
Environmental Protection Agency, Research Triarg.le Park, NC, March
1979.
4. "Standards of Performance for Nitric Acid Plants", 40 CFR 60. G.
5.9-6 EMISSION FACTORS 10/8C
-------
5.10 PAINT AND VARNISH
5.10.1 Paint Manufacturing
The manufacture of paint involves the dispersion of a colured oil or
pigment In a vehicle, usually an r
-------
TABLE 5.10-1. UNCONTROLLED EMISSION FACTORS F0>% PAINT AND
VARNISH MANUFACTURING*1
EMISSION FACTOR RATING: C
Partlculate
Type of
predict
Paint'1
Varnish
Bo< ying oil
OLioresinous
Alkyd
Ai rylic
kg/Mg
pigment
10
-
-
-
—
Ib/ton
pigment
20
-
-
-
-
Nonmethane VOCC
kg/Mg
of product
15
20
75
30
10
Ib/ton
of product
30
40
150
160
20
References 2, 4-8.
ij
Afterburners can reduce VOC emissions by 99% and
partlculates by about 90S. A water spray and oil filter
s/stem can reduce partlculates by about 90%.
Expressed as undefined organic compounds whose composition depends
upon the type of solvents used in the manfacture of paint and
varnish.
Reference ^. (articulate matter (0.5 - 1.0 %) is emitted from
pigment handling.
References for Section 5.10
1. Air PollutantEmission Factors, APTD-0923, U. S. Environmental Protection
Agency, Rnsearch""rriangle Park, NC, April 1970.
2. R. L. Stenburg, "Controlling Atmospheric Emissions from Paint and Varnish
Operations, Part I", Paint and Varnish Producrton, September 1959.
'). Private Communication between Resources Research, Inc., Res tun, VA, and
National PaJ.nt, Varnish and Lacqutsr Association, Washrngton, DC.,
September 1969.
4. Unpublished engineering estimates based on plant visits in Washington,
DC, Kc-S3urces Research, Inc., Reston, VA, October 1969.
5. Air Pollution^ Engineering Manual, Second Edition, AP-40, U. S.
Environmental Prntecti.cn Agency, Research Triangle Park, NC, May 1973.
6. F.. C. LunchtJ, et al., "Distribution Survey of Products Emitting Organic
Vapors in Los Angeles County", Chemical Engineering Progress,
_53_(8):l>71-376, August 1957.
5.10-2 EMISSION FACTORS 5/33
-------
7. Communication on emissions from ,)air>t and varnish operations between
Resources Research, Inc., Res tor., VA, "nd G. Sallae, Midwest Research
Institute, Kansas City, MO, December 17, 1969.
8. Oommunicalloa between Resources Research, Inc., Res ton, VA, and Rog«r
Higgins, Benjamin Moore Paint Company, June 25, 1968.
5/83 Chemical Process Industry 5.10-3
-------
5.11 PHOSPHOPIC ACID
Phosphoric acid Is produced by two principal methods, the wet
process and the thermal process. The wet process is employed when the
acid Is to be used for fertilizer production. Thermal process phos-
phoric acid is of higher purity and is used in the manufacture of high
grade chemical and fjod products.
1 2
5.11.1 Process Description *
5.11.1.1 Wet Process Acid Product-Ion - In modern wet process phosphoric
acid plants, as shown in Figure 5.11-1, finely ground phosphate rock,
which contains 31 to 35.5 percent phosphorus pentoxide ^Oj), is
continuously fed into a reactor with sulfuric acid which decom^cses the
phosphate rock. In order to make the strongest phosphorl: acid possiu.
and to decrease later evaporation costs, 93 or 98 percent si-'lfuric acids
are normally used. Because the proper ratio of acid to rock in th<>
reactor must be maintained as closely as possible, precise automatic
process control equipment is ^raployeu ia the regulation of these two
feed streams.
ni crystals (CaSO^ . 21^0) are r recipit Jted by the phosphate
rock and suit uric acid reaction. There LS j-ittle market for the gyps'.m,
so it is handled as waste, filtered out of the acid and sent to settling
ponds. Approximately 0.7 acres of cooling and settling pond are required
for eveiy ton of dail'1 PjOs production.
Considerable heat is generated in the reactor, which must be
ed. In older plants, this is done by blowing air over the hot
slurry surface. Modern plants use vacuum flash coolirg of part of the
.slurry, then sending it back into the reactor.
The reaction slurry is held in Uie reactor for periods of up to
eight hou-s, depending on the rock, and reactor design, and is then sent
to be filtered. This produces a 32 percent acid solution, which gener-
ally needs concentrating for further use. Current practice is to
concentrate it iu two or three vacuum evaporators to about 54 percent
5.11.1.2 Thermal Process Acid Production - Raw materials for the
production of phosphoric acid by the thermal process are elemental
(yellow) phosphorus, air and water. Thermal process phosphoric acid
nanuf acture , as shown in Figure 5.11-2, typically involves three steps.
First, the liquid elemental phosphorus is burned (oxidized) in a
combustion Chamber at temperatures or' 3000 no 50QO°F (1650 - 2760eC) to
form phosphorus pentoxide. Then, the phosphorus pentoxide is hydrated
with dilute acid or water to produce phosphoric acid liquid and mist,
The final steo is to remove, the phosphoric acid mist frym the gas
stream.
2/HO t h. Mii.al I'r.H, - l.i,ln>lr> .VIM
-------
irti
^F9
f ft
.
i
A
1
p— •/
i
1
i_
oJ
f
r
nj
-1
Ht[,fc3f L-01 !CIC I.'" 0
Figure 5.11-1. Flow diagram of wet process phosphoric acid plant.
STACK
E'FIJIM
(«[» « ^,1-3^ HIST)
•CID TRE»TI^C.
5TACH Cfri.E
(Am • HE;
6LDW-1I PI.MP
»CID nt[JT>r, SECTION
lU'^EC > TH[
FOR FXD AIO
DF A( ,' J
Figure 5.11-2. Flow diagram of thermal process phosphoric ^cid plant,
,•>. I I --2
2/Hf)
-------
The reactions involved are:
Pi, + 5 02 -*• P^OIQ
P.»010 + 6 H20 + 4
Thermal process acid normally contains 75 to 85 percent phosphoric
acid (H^POtt). In efficient plants, about 99.9 percent of the phosphorus
burned iii recovered as acid.
1-T
5.11,2 Emissions and Controls'""
Sill. 2.1 Wet Process Emissions and Controls - Gaseous fluorides, mostly
silicon tetr<»f luoridu and hydrogen fluoride, are the major emissions
from wet process acid. Phosphate rock contains 3.5 to 4.0 percent
fluorine, and the final distribution of this fluorine in wet process
acid manufacture varies widely. In gaacrrl , part cf the fluorine goes
with the gypsum, part with the phosphoric acid product, and the rest is
vaporized in the reactor or evaporator. The proportions and amounts
going with the gypsum and acid depend on the nature of the rock ami
process, conditions. Disposition of the volatilized fluorine depends on
the design and operation of the plant. Substantial amounts can pass off
into the air, unless effective scrubbers are used. Some of the fluorine
which Is carried to the settling ponds with the gypsum will get into the
atmosphere, once the pond water is saturated with fluorides.
The reactor, where phosphate rock is decomposed by sulfuric acid,
is the main source of atmospheric contaminants. Fluoride emissions
accompany the air used to cool the reactor slurry. Vacuum flash cooling
has replaced the air cooling method to a large extent, since emissions
are minimized in the closed system,
Acid concentration by evaporation provides another source of
fluoride emissions. It has been estimated that 20 to 40 percent of the
fluorine originally present in the rock vaporizes in this operation.
Total paniculate emissions directly from process equipment were
measured for one digester and for one filter. As much ?.s 11 pounda of
particulates per ton of P20j wtre produced by tne digester, and approxi-
mately 0.2 pounds per ton of ~P20^ were released L-/ the filter. Of this
particulate, 3 to 6 percent was fluorides,.
Particulate emissions occurring from phosphate rock handling are
covered in Section 8.18.
5.11.2.2 Thermal Process Emissions and Controls - The principal
atmospheric emission from the thermal process ir phosphoric acid mist
(H3PO(<) contained in the gas stream from the hydrator. The particle
size of the acid mist ranges from 0.4 to 2.6 micrometers. It is not
uncommon for as much as half of the total phosphorus pentoxide to be
present as liquid phosphoric acid particles suspended in the gas stream.
2/'HO rhcum-iil I'roo •«•. linlii-
-------
Economical operation of rhe process demands chac this potential loss be
controlled, so ail plants ara equipped with some t>^e of eoiESion
control equipment.
Control equipment conmoniy used in thermal prnceen phosphoric acid
plants includes ventnri scrubbers, cyclonic separators with vire mesh
Eiist eliminators, flier mist eliminators, high energy wire mush contactor?,,
and electrostatic pracipitators.
Table 5.11-1. EMISSION FACTORS FOK. PHOSPHORIC
ACID PRODUCTION
EMISSION FACTOR RATING: B
Source
Wet Process
Reactor, uncontrolled
Gypsum settling and
c
cooling ponds
Condenser, uncontrolled
Parti r.ulates
Ib/ton
— m
kg/MT
«.
Fluorine
Ib/ton
56.4
1.12
61.2
kg/Ml
28,2
0.56
30.6
Typical controlled
emissions'1 - - .02-.07 .01-.
e t
Thermal Process '
Packed tow^r (95.52) 2.14 1.07
Vencuri s.-.rubber (97.5%) 2.53 1.27
Glass fib'-.r mist
elimina :or
(96.0 - 99.9%) 0.69 0.35
Wire mesh mist eliminator
(95.0%; 3.46 2.73
High pressjre drop mist
eliminator (?9.9%) 0.11 0.06
Electiostatic precl~itator
(98 - 99as) 1.66 0.83 - -_
vAeid mist, particulates (0.4 - 2.6 urn).
Reference j 1 and 3. Pounds of fluorine (as gaseous fluorides) per
ton of P2n5 produced. Base-J or a material balance of fluorine from
phcspliatc rock of 3.9% fluorine and 33% PnO5.
Approximately 0.7 acres (0.3 hectares) of rooling and settling pond are
required to produce 1 ton of PaOs daily. l;mis;; tons in terms of pond
.area would be 1.60 Ib/acre per day (1.79 kg/hectare per day).
Referenca b.
Reference 3. Pounds of particulate per ton of
f.umbera in p
each device.
f.umbera in parentheses indicate the control efficiency associated with
.-. I I -1 EMISSION FACTORS 2/W>
-------
References for Section 5.11
1- Atmospheric Emissions from Wet Process Phosphoric Acid
Manufacture, AP-57, National Air Pollution control Administration,
NC, April 1970.
2 • Atmospheric Emissionr f lorn Thermal Process Phosphoric Acid
Manufacture, AP-48, National Air Pollution Control Administration,
Durham, NC, October 1968.
3. Control Techniques for Fluoride Emission a, Unpublished, U.S. Public
Health Service, Research Triangle P-jrk, NC, September 1970.
A. W.R. King, "Fluor ina Air Pollution fron Wet Frc-rea^ Phn.'iphorii; Acjd
Plants - Water T'onJs", Doctoriil '-heeis, Supported by Ei-A Research
Grant No. R-800950, North Carolina State University, Raleigh, NC,
1974.
5. Final Guideline Document: Ccntrol of Fluoride Emiaaions from
Existing rho^ate Fertilizer Plants. EPA-4 50/2- 7 7-005, U.S.
Environmental Protection Agency, Research Trtangl? Park, NC, March
1977.
2/tt() Cliciniriil I'rori-.^s ln. I f ..>
-------
5.12 I'HTHALIC ANHYDRIDE
j.12.1 General1
Phthalic anhydride (PAIN) production in the United States in 1972 was 0.9 billion pounda per year;
this total is estimated to increase to 2.2 billion pounds per year by 1985, Of the current production, 50
perrenl is used for planticizera, 25 percent foralkyd resins, 20 percent for unsaturated polyester reeim,
and 5 percent for miscellaneous and exports. PAN in produced by ralalyuc oxidation of either ortho-
; ylene or naphthalene. Since naphthalene is a higher priced feedstock and ha' a lower feed utilization
(about 1.0 Ib PAN/lb o-xylene versus 0.97 Ib PAN/lb naphthalene), future production growth is pre-
dicted to utilize o-xylene. Because emission factors are intended for future as well at present applica-
tion, this report will focus mainly on PAN production utilizing o-xylene as the main feedstock.
The processes for producing PAN b o-xylene or naphthalene are the same except for reactors,
rataly*t handling, and recovery facilities required for fluid bed reactors.
In PAN production using o-xylene as the basic feedstock, filtered air is preheated,compressed, and
mixed with vaporized o-xylene and fed into the fixed-bed tubular reactors. The reactors contain the
catalyst, vanadium penloxide, and are operated at 650 to 725°F (340 to J85°C). Small amounts of
rulfur dioxide are added to the reactor feed to maintain catalyst activity. Exothermic heat is removed
jy a molten ealt bath circulated around the reactor tubes and transferred to a steam generation system.
Naphthalene-based feedstock is made up of vaporized naphthalene and compressed air. It is
transferred lo the fluidized bed reactor and oxidized in the presence of a catalyst, vanadium pent-
oxide, at 650 to 725° F (340 to 385°C). Cooling tubes located in the catalyst bed rejiove the exothermic '
heal which is used to produce high-pressure steam. The reactor effluent consists of PAN vapors, en-
trained catalysl. <:nd various by-products and non-reactant gas. The catalyst is removed by filtering and
returned to the reactor.
The chemical reactions for air oxidation of o-xylene and naphthalene are as follows.
CH3
302
3H20
o-xylene + oxygen
phthalic
anhydride
water
•I- ZH20 + 2C02
naphthaline •(-
0
oxvgen nhthilic + miter + carbon
anhydride dioxids
• k -•»--—- i-^<
Cher:icai Process Industry ' A 4 -—• f
-------
The reactor effluent containing crude PAN plus product* from side reaction! and excess oxygen passes
to a series of switch condensers where the crude PAN cool§ and crystallizes. The condensers are alter-
nately cooled and ihm heated, allowing PAN crystals to form and thrn melt from ihe condenser lube
fins.
The crude liquid is transferred to a pretreatment section in which phthalic acid is dehydrated to
anhydride. Water, maleic anhydride, and benzoic acid are partially evaporated. The liquid then ^ues
to a vacuum distillation «?><:tion where pure PAN (99.8 wt. percent pure) is recovered. The product can
be stored and fhipp d either as a liquid or a jolid (in which case it is dried, flaked, and packaged in
multi-wall paper \ *gs) Tanks for holding liquid PAN are kept at 300°F (150'JC) and blanketed with
dry nitrogen to prevent the entry of oxygen (fire) or water vapor (hydrolysis to ohthaiic acid).
Maleic anhydride is currently the only by-produrl being recovered.
Figures 1 and 2 show the process flow lor air oxidation of o-xylene and naphthalene, respectively.
5.12.2 Emissions and Controls'
Emissions from o-xylcne and naphthalene storage are small and presently arc not controlled.
The major contributor of emissions is the reactor and condenser effluent which is vented from the
condenser unit. Particular, sulfur oxides (for o-xylene-based production), and carbon monoxide
make up the emissions, with carbon monoxide comprising over half the total. The n»osl efficient (96
percent) system of control is the combined UHage of a water scrubber and thermal incinerator. A
thermal incinerator alone is approximately 95 percent efficient in combustion of pollutants for o-
xylene-based production, and 80 percent efficient for naphthalene-based production. Thermal incin-
erators with steam generation thuw the same efficiencies as thermal incinerators alone. Scrubbers
have a 99 percent efficiency in collecting participates, but are practically ineffective in reducing car-
bon monoxide emissions. In naphthalene-b^sed production, cyclones can be used to control catalyst
dust emissions with 90 to 98 percent efficiency.
Pretrealmenl and distillation emissions participates and hydrocarbons are normally processed
through the water scrubber and/or incinerator used for the main process stream (reactor and con
denser) or scrubbers alone, with the same efficiency percentages applying,
Product storage in the liquid phase results in small amounts of gaseous emission?. These pa.
strearrfc can either be sent to the main process vent gas control devices or first processed through
| sublimation boxes cr devices used to recover escaped PAN. Flaking and bagging emissions are negli-
gible, but can be /it to a cyclone for recovery of PAN dust. Exhaust from the cyclone presents no
t problem.
•
Table 5.12-1 pi»t^ cmis-iion factors for rrmtrolleH and inn onlrulled i;m>>ions from the production
of
5.12-2 EMISSION FACTORS 5/B3
A
-------
Ui
OO
PAHTICULATE
SULFUR OXIDE
CARBON MONOXIDE
AIR.
'FILTER AND
COMPRESSOR
a ..YLENE.
3
^"
3
^
n
V
en
3
ft.
c
S02-
SALT COOLER AMD
STEAM GENERATION
HOT AND COOL
CIRCULATING
OIL STREAMS/
WATERANOSTEAM
J
•^flOlLERFEEO
WATER
MM
.
i t
1
SWITCH
CONDENSERS
CRUDE
PRODUCT
STORAGE
PARTICIPATE
PARTICULAR
PAHTICULATE
HYDROCARBON
PRETHEAT
MENT
s-J
STE*M-
STRIPPER
COLUMN
<
REFINING
COLUMN
-STEAM
PHTHALIC
'ANHYDRIDE
PARTICULATE
HYDROCARBON
Figure 5.12-1. Flow diagram for phthalic anhydride using oxylene as oasic feedstock
1
-------
U1
r>
O
a
'X
L.T
00
HOT AND COOL CIRCULATING
OIL STREAMS OR
NAPHTHALENE.
AIR
<;
"N
f
FLUID
ncn
IA
HE
FILiER
TAIfl'ST
CYCLE
WAT
HIGH
| ^ PRESSU
^JL_ STEAM
STEAM
DRUM r
— * v.
kHANDSIEAM —
ttu
SWITCH
CONDENSERS
HE
^s
CRUDE STORAGE 1
_ PARTICULATF
CARBON MONOXIDE
PARTICULATE
REACTOR
BOILER FEED
WATER
COMPRESSOR
PHE
TREAT
MENT
TANK
. PARTICULATE
HYDROCARBON
COOLING
PRODUCT
STORAGE
(MOLTEN!
FLAKING AND
BAGGING
OPERATION
(OPTIONAL)
PHTHALIC ANHYDRIDE
PART'CULATE
HYDROCARBON
Figure 5.12-2. Flow diagram for phthalic anhydride using naphthalene as basic feedstock.
-------
TABLE 5.12-1. EMISSION FACTORS FOR PUTHALIC ANHYDRIDE
FMISSION FACTOR RATING: B
Participate SO (oawthau
Proceea
Oxidmoa cl o-xylenec
Main proceea atreea
'Jncontrol led
V/acrublier u.i theraal
Incinerator
W/ thermal Incinerator
W/lDcinaritor "1th
•teen generator
Pret reatecnt
Uncontrolled
U'/ecrubber a;i^ thermal
inclneri'.or
Uncontrollec
W/(crubb«r aic there* T
!iclo*rator
L'/thena] inclnantor
Oxidation of naphthalene0
Main proceaa ilreaei
Uncontrolled
U/thenul Incinerator
W/aerubbar
PretreatBtnt
Uncontrolled
W/ thermal incinerator
W/ec rubber
Dlatlllatlon
Uncontrolled
w/tiieratl Incinerator
W/acrubber
ii/m
69*
j
It
*
6..»
0.3
01
• *»
45*
2
2
28
6
0.1
2.5J
0.5
• vacb
XWIM
0
0
0
0
0
0
< 0*1
0.1
0
0
0
0
0
c
. jh,l
2
0.1
CO
'I/I*
151
6
8
1
0
0
0
0
0
50
13
M
0
0
0
J
3
0
Ik/10.
301
12
15
IS
0
0
0
c
0
100
20
100
D
U
D
0
0
0
'Reference 1. Factors are in kg nf pollutant/Kg (IV/ten) of phOiallc anhydride produced.
D
Enleeionr coatalr no eoth ne.
cCantrol devlcea listed are those currently being uaad by phthallc anhydride planta.
'Stair proceae atream includee reactor aud oulLlple evlic/i condaaaer* a* vented through crgdenaar unit.
cConalite o'. phth^llc anhydride, aalilc anhydride, beniolc acid.
Value thown corrtaponde to relatively fraih cttalytt, which can change with catalyat a(*. Can be 9.5 - 13 kg/Kg
(19 - 2i Ib/tDTi) tor aged catalyel.
*Conela'.a of phthallc anhydride and male-c . ihydrlde,
Xonaall> a vapar, bit can be preaent aa a partlculete at low teeiperatura,
Conai'ti of phthallc anhylr.de, evilalc anhydride, tuphthaqulnon*.
JP*rttc'tlate IE phthaHr anhydride.
Does not Include catalyet dual, controlled by cyclcnee with efficiency af 90 -
Reference for Section 5.12
1. Engineering and Cost Study of Air Pollution Control for the
Petrochemical Industry, Vol. 7; Phthalic Anhydride Manufacture
from Ortho-xylene, EPA-450/3-73-006g, U. S. Environmental Protection
Agency, Research Triangle Park, NC, July 1975.
5/33
Chemical Process Industry
5.12-5
-------
5.1.J PLASTICS
S.I 3.1 Process Description1
The manufacture of most resins or plastics begins with the polymerization or linking of the basic compound
(monomer), usually a gas or liquid, into high molecular weight noncrystalline solkJs. The manufacture of the
basic monomer is not considered part of the plastics industry and is usually accomplished at a chemical or
petroleum plant.
The manufacture of most plar.tics involves an enclosed reaction or poiymeiization step, a drying step, and a
final treating and forming step. These plast-cs are polymerized or otherwise combined in completely enclosed
stainless steel or glass-lined vessels. Treatment of the resin after potmerization varies with the proposed use.
Resins for moldings are dried and crushed or ground into molding powder. Resins such as the alkyd resins that are
to be used for protective coatings are normally transferred to an agitated thinning tank, where they are thinned
with son,- type of solvent and then stored in large steel tanks equipped with water-cooled condensers to prevent
loss of solvent to I he atmosphere. Still other resini are stored in latex form as they come from the kettle.
5,13.2 Emissions and Controls'
The major sources of air contamination in plastics manufacturing are the emissions of raw materials or
monomers, emissions of solvents or oiher volatile liquids during the reaction, emissions of sublimed solids such as
phthalic anhydride in alkyd production, and emissions of solvents during storage am! handling ur thinned resins.
Emission factors for the manufacture of plastics are shewn in Table 5.13-1.
Table 5.13-1. EMISSION FACTORS FOR PLASTICS
MANUFACTURING Wl TO OUT CONTROLS*
EMISSION FACTOR RATING: E
Type of plastic
Polyvmyl chloride
Polypropylene
General
Paniculate
Ib/ton Tkfl/MT
35b I 17.5b
3 1 1.5
5 to 10 2 5 to 5
Gases
Ib/ton
17C
0.7d
kg/MT
8.5C
0.350
'References 2 and 3.
^Usually ctti.-olled wuh a fabric filter efficiency of 98 to 99
percent.
cAs vinyl chloride.
"As (Kopylene.
Much of the tinlrot equipment used in this industiy is a basic part of the sysu-m and serves to recover a
rcactant or product. These controls include floating roof tanks or vapor recovery systems on volatile material,
storage units, vapoi' recover.' systems (adsorption or condensers), purgy lines that vent to a flare system, and
recovery systems on vacuum exhaust lines.
2/72
Chemical Process Industry
5.13-1
-------
References for Section 5 13
1. Air Pollutant Emission Factors. Fir.al Repoit. Resources Research, Inc. Reston, Va Prepared Tor National
Air Pollution Control AdminBtratijn, Durham N.C. under Contract Number CPA-22-69-119. April 1070.
2. Unpublished data frcrr industrial questionnaire. U.S. DHEW, PriS, National Air Pollution Control
Administration, Diviiicv. of Air Quality and Emissions Data. Durham, N.C 1969
3 Private Communication between Resources Research, Incorporate, and MaryUnJ State Department of
Health, Baltimore, Md. November 1969.
5.13-2 EMISSION FACTORS 2/72
-------
5.14 PRINTING INK
5.14. i Process Description'
There are ibur major classes of printing ink: leileipr^ss jnd lithographic inks, commonly called oil or pasle
inks, -ml flexographic and rotogravure inks, which arc rcfcncJ u> ;is solvent inks These inks v-jry considerably in
physical appearanco, composition, method of application, and. drying mechanism. Flexographic. and rotogravure
inks have niany elenienfs in coi .non with the paste ink: hut differ in that they arc of very low viscosity, and they
almost always dry by evaporation of highly volatile solvents.'
There are three general proccss.-s in the manufactuie of priming inks: (I) cooking the vehicle and adding dye*,
(2) grinding of a pigment into Ihc vehicle using a roller mili, and (3) replacing water in the wet pigment pulp by
an ink vehicle (commonly known as the flushing process).J The ink "varnish" or vehicle is generally cooked in
large keitlts at 200° »o (>00°F (93° to 315°C) for an average of X lo 12 hours in much the same way that regular
varnish is made. Mixing of the pigment ^nd vehicle >: dune ir. duugh mixers or in large agitated tanks. Grinding is
most often civried out in three-roller or five-ioiler horizontal or vertical mills.
5.14.2 Emissions and Controls'd
Varnish or vehicle preparation by heatmp is by far the latgcst source of ink niarufacturing emissions. Cooling
the varnish com|>onents - lesins, drying oils, petroleum oils, and solvents - produces odorous emissions. At
about 350°F (175°f) the products begin to decompose, resulting in (he emission of decomposition products
from the cooking vessel '•niisiions contin:je throughout the cooking process with the maximum rale of emissions
occuring iust after the maximum temperature has been reached. Emissions from the cooling phase can be
reduced by more than ~)Q percent with the use of scrubbers or condensers followed by afterburners.4-5
Compounds emitted from the cooking of oleoresinuus varnish (resin p'us varnish) include water vapur. fatly
ac'ds, glycerine, acrolcin, pheiuils, aldehyde;, ketones, terpene oils, tcrpenes, and caibon dioxide. Umissions of
thinning solvents used in flexographic and rot 3giavurc inks may also occur.
The qiantity, composition, and rate of emissions from ink manufacturing depend upon the cooking
tenpcratuic anJ tin.e, the ingredients, Ifis method of introducing additives, the degree of sti.Ting, and the extent
of air or inert gas blowing. Paiticulatc emission-, ifsuhing from the ;i
-------
TABLE 5.14-1. EMISSION FACTORS FOR PRINTING INK
MANUFACTURING
EMISSION FACTOR RATING: E
Konme thane ,
volatile organic compounds
Type of process
Vehicle cooking
General
Oils
Oleoresinous
Alkyds
Pigment mixing
kg/Mo
oi product
60
20
75
80
NA
Ib/ton
ot product
120
40
150
160
«* i
ilrt
Participates
kg/Mg
of pigment
NA
NA
NA
NA
1
Ib/ton
of pigmenc
NA
NA
NA
NA
2
s
Based on data from Section 3.10, Paint and Varnish. NA - not applicable.
The nnraethane VOC emissions are a mix of volatilized vehicle ojmponents,
cooking decomposition products and ink solvent.
References for Secclon 5.14
1. Air Pollutant Euission Factors, APTU-0923, U. S. Environmental
Protection Agency, Research Triangle Park, NC. April 1970.
2. R. N. Shreve, Chemical Process Indus trie", 3rd Eo., New York, McGraw
Hill Book Co., 1967.
3. L. M. Larsen, Industrial Printing inks, New York, Reinhold Publishing
Cumpany, 1962.
4. Air Pollutiori Engineering ''.anuaU 2nd Edition, AP-40, U. S. Environmental
Protection Agency, Research Triangle P^rk, NC, May 1973.
5. "rivate conraurii cati^ . with Ink Division of Interchemical Corporation,
Cincinnati, Ol.io, Novetiber 10, 19o9.
5.14-2
EMISSION FACTORS
5/83
-------
f>.l3 SOAP AND DETEKGLNTS
5.15.1 Soap Manufacture
Process Description ' - Soap may be manufactured by ?ither a batch os
continuous process, using eitnei the alk:ilinp .;aponif ication cf natural fats
and oil a or the direct saponifies tion of fatty acids. The kettle, or full
boiled, process is a batch process of s^ver.-jl. t>*.ep3 in either a single kettle
(.ic a scries of kettles, Fats and oils arc saponified by live st^^m bailing in
a caustic .solution, followed by "graining", or precipitating, the soft cuiJs
of soap out of the aqueous lye solution by adding sodium chloride (salt). The
soap solution then is washed to remove glycerine and color body impurities, to
le.jye the "neat" soap to form during a settling period. Continuous alkaline:
siiponif icaLion of natural fats and oils follows the same steps as batch
processing, but it eliminates the need for a lengthy process time. Direct
s-ipoiilf icat ion of fatty acids is alsc accomplished in continuous processes.
Fatty adds obtained by continuous hydrolysis usually are continuously
neutral : /.ed wi t,i caustic soda in a high sp.-»ed ir,:xer/neutralizer to form soap.
\] i so;jp is finished fur consumer use i~ L'uch various forms as liquid,
powder, grauu.e, chip, [lake or bar.
Emissions and Controls - The nviin atmospheric pollution problem in the
manufacture of soap is odor. Vent lines, vacuum exhausts, product and raw
mateiial storage, and waste streams are all potential odor sources. Control
of these odors may be achieved by scrubbing all exhaust fumes and, if
necessary, incinerating the remaining compounds. Odors emanating from the
.spray drier ruiy be controlled by scrubbing with an scid solution.
BUudi-.ig, mixing, drying, packaging and other physical operaiLjns are
subject tu dust emissions. The production of soap powder by spray dryiny is
the largest single source of dust in the manufacture of soap. Dust emissions
troni finishing operations other than spray drying can be controlled by dry
fillers and haghousi'-s. The l^i^e size i;T the p«n L icui ates in soap drying
means that high efficiency cyclones installed in series can be satisfactory in
controlling emissions.
5.1">. 2 Detergent Manufacture
1 7— H
Process Description ' - The ranuf.acture of spray dried detergent has three
n.iin processing steps, slurry preparation, spray drying and granule
I-'igure 5.15-1 Illustrates t..e various operations. Oetergent slurry _s produced
by blending liquid surfactant with powdered and liquid materials (builders and
other additives} in a closed nix.lng r.ank called u crutc'ier. Liquid surfactant
used in rrakin% the detergent slurry is produced by tht; sulfonation or sulf.^tion
by sulfuric acid of a linear alkylate or a tatty acid, which is th».n neutralized
with caustic solution (NaOH). The hlendsd Blurry is held in a surj'.e vessel
for continuous pumping to th>> spray dryer. Th° slurry is sprayed at high
pressure through nozzles into a vertical drying tower having a stream of hot
air of from 315° to 400°C (oOO° to 750°F). Most towers designed for detergent
production aro countercurr«vnt , with slurry introduced *t the top and heated
5/S3 Chemical Process Industry 5.15-1
-------
RECEIVING,
STORAGE,
TRANSFER
SLURRY PREPARATION
SPRAY DhYING
BLENDING
AND
PACKING
o
O
5G
C/l
DRY DUST
COLLECTORS
J
SURFACTANTS:
SLURRY
ALCOHOLS
ETHOXYLATES
BUILDERS:
PHOSPHATES
SILICATES
CARBONATES
WATER
j MIXER J
CRUTCHER
P
LY
SURGE
VESSEL
ADDITIVES:
PERFUMES
DYES
ANTICAKING AGENTS
TO CRUTCHER
AND POST-
ADDITION MIXER
CONTROL
DEVICE
I
HIGH
PRESSURE
PUMP
HOT AIR
L
|FURNACE I
DRY DUST
COLLECTORS
SPRAY
DRYING
TOWEH
POST-
AOOITION
MIXER
f
PACKAGING
EQUIPMENT
GPANULEF
STORAGE[
FINISHED
DETERGENTS TO
WAREHOUSE
CONVFYOR
L/i
LC
Fiqure 5.15-1. Manufacture of spray dried detergents.
-------
air introduced at the bottom. A few towers are concurrent and have both hot
air and slurry Introduced at the top. The detergent granules are mechanically
or air conveyed from the tower to a mixer to incorporate additional dry or
liquid ingredients and finally sent to packaging and storage.
7—8
Emissions and Controls - In the batching and mixing of fine dry ingredients
to form slurry, dust emissions are generated at scale hoppers, mixers and the
crutcher, Baghousss and/or fabric filters .-re used not only to reduce or to
eliminate the dust emissions but to recover raw materials. Trie spray drying
operation is the major source of particulate emissions from detergent manu-
facturing. Paniculate emissions from spray drying operations are sho-;n in
Table 5.15-1. There is also a minor source of volatile organics when the
product being sprayed contains org,-nic materials with low vapor pressures.
These vaporized organic materials condense in the tower exhaust air stream
into droplets or particles. Dry cyclones and cyclonic impingement scrubbers
are the primary collection equipn-ent employed to capture the detergent dust in
the spray dryer exhaust for return to process. Dry cyclones are used in
parallel cr in series, to collect particulate (detergent dust) and to recycle
the dry product back to the crutchar. Cyclonic impinged scrubbers are used in
parallel to collect the participate in a scrubbing slurry which is recycled
back to the crutcher. Secondary collecticn equipment is used to collect the
fine paiticulates that have escaped from the primary devices. Cyclonic
impingement scrubbers are often followed by mist eliminators, and dry cyclones
are followed by fabric filters or scrubber/electrostatic precipitator units.
Conveying, mixing ami packaging of detergent granules can cause dust emissions.
Usually baghouses and/or fabric filters provide the best control.
TABLE 5.15-1.
PARTICULATE EMISSION FACTORS FOR SPRAY DRYING
DETERGENTS3
EMISSION FACTOR RATING: B
PartlcuJate Emissions
Control
Device
Uncontrolled
. , b
Cyclone
Cyclone
w/Spray chamber
w/Packed scrubber
w/Venturi scrubber
Over a I.1.
Efficiency, %
_
85
92
95
97
kg/Mg of
product
45
7
3.5
2.5
1.5
Ib/ton of
product
90
14
7
5
3
References 2-6. Emissions data for volatile organic compounds ha;
.not been reported In the literature.
Some type of primary collector, such as a cyclone, is considered
an integral part of the spray drying syctem.
5/83
Chemical Process industry
5.15-3
-------
Rafevancaa for Section 5.15
1. Air Pcllatans. Emission Fact or a, APTD-0923, U. S. Environmental Protection
Agencv, Research Triangle Park, NC, April 1970.
2, A. H. Phelps, "Air Pollution Aspects of Soap and Detergent Manufacture",
J Carnal of the Air Pollution Control Association, 17(8):505-507, AugUHt
T967.
3. R. N. Shi eve. Chemical Process Industries, Third Edition, New York,
McGraw-Hill Book Company, 1967.
ft. G. P. Lars en, et al., "Evaluating Sources of Atr Pollution", Industrial
and Engineering Chemistry. ^5:1070-1074, May 195J-
5. P. Y. McCormick, et al., "Gas-solid Systems", Chemical Engineer's Handbook,
J. H. Perry (ed.), New York, McGraw-Hill Book Company, 1963.
6. ConmunJcation with Maryland State Department of Health, Baltimore, MD,
November 1969.
7. J. A. Danieison, Air Pollution Engineering Manual, AP-40, U, S.
Environmental Protection Agency, May 1973.
8. Source Gregory Survey; Detergent Industry, E'A-450/3-80-030, U S.
Environmental Protection Agency, Research Triangle Park, NH, June 19HO.
5.15-4 EMISSION FACTORS 5/S3
-------
5.16 SODIUM CARBONATE
5.16.1 General1'2
Processes used to produce sodium carbonate (Na2C03), or soda ash, are
clasbified as either natural or syrthetic. Natural processes recover sodium
carbonate from naturally occurring deposits of trona ore (sodium sesquicar-
Donate) or from brine containing sodium sesquicarbonate and sodium carbonate.
The synthetic process (Solvay process) produces sodium carbonate by reacting
ammoniated sodium chloride with carbon dioxide. For about a century, almost
all sodium carbonate production was by the Solvay process. However, since
Che mid-196C'fi, Solvay process production has declined substantially, and
natural production has grown by 500 percent. Only one plant xn th? U.S. now
uses the Solray process. Available data on emissions from the Solvay process
are also presented, but because- the natural processes are more prevalent in
this country, this discussion will focus on emissions from the natural
processes.
Three different natural processes are currently in use. These are the
monohydrate, sesqulcarbona .e and direct cerbonation processes. The sesqul-
carbonate process was ".he first natural process used, but it is used at only
one plant and is nut expected to be used at future plants. And since data
on uncontrolled emissions from this process are not available, emissions
from the sesquicarbonate process are not discussed. The monohydrate and
direct r.arbonation processes and emissions are described below, the differ-
ences in these two processes being in raw materials processing.
In the monohyurate process, sodiirn carbonate is produced from trona
ore, which consists of 86 to 95 percer.t sodium sesquicarbonate
(Na2C03 • NaHC03 • 2H20), 5 to 12 percent ganguea (clays and other Insoluble
impurities) and water. The mined trcna ore is crushed and screened and
calcined to drive off carbon dioxide and water, forming crude sodium carbon-
ace. Rotary gas fired calclners currently are most commonly used, but the
newest plants us« coal fired calcines, and future plants are also likely to
use coal tired calciners because of the economics* and the limited Avail-
ability of natural gas.
The crude sodium carbonate if dissolved and separated from the insoluble
impurities. Sodium carbonate monchydrate (Na2COj • H20) is crystallized
from the purified liquid by multiple effect evaporators. The sodiun carbon-
ate monohydrate is then dried, tj remove the free and bound water and to
produce the final product. Rotary steam tube, fl^d bed steam tr-be, and
rotary ga3 tired dryers are used, with steam tube dryers more likely in
future plants.
In the direct carbonation process, sodium carbonate is produced from
brine containing sodium sesquicarbonate, sodium carbonate and othar salts.
The brine is prepared by pu^pirg liquor Into salt deposit?, where the salts
8 '82
Chemical Process Ind-iHtry 5.16-1
-------
are dissolved into a liquor. The recovered brine is carbonated by contact
with carbon dioxide to convert all of the sodium carbonate that is present
to sodium bicarbonate„ The sodium bicarbonate is then recovered from the
brine by vacuum crystallizers. The crystal slurry IB filtered, and the
crystals enter steam heated predryers to evaporate some of the moisture.
The partially dried sodium bicarbonate goes to a 3Learn heated calciner where
carbon dioxide and the remaining water are driven off, forming Impure sodium
carbonate. The carbon dioxide evolved is recycled to the brine carbonators.
The impure sodium carbonate is bleached with sodium nitrate in a gas fired
rotary bleacher to remove discoloring impurities. The bleached sodium
carbonate is then dissolved and recrystallized. The resulting crystals of
sodium carbonate monohydrate are dried, aa in the monohydrato process.
In the Solvay process, arumonia, calcium carbonate (limestone), coal and
sodium chloride (brine) are ti'.e basic raw materials.. The brine is> purified
in a series of reactors and i.larifiers by j. • ecipitating the magnesium and
calcium ions with soda ash and sodium hydroxide. Sodium bicarbonate is
formed by carbonating a solution of ammonia and purified brine which is fed
to either stjam or gas rotary dryers where it is c.orverted (calcined) to
sodium carbonate,
5.16.2 Emissions and Controls
The principal emission points in the monohydrate and direct carbonation
processes are shown in Figures 5.16-1 and 5.16-2. The major emission sources
in the rnonohydrat.e process are calciners and dryers, and the majcr sources
in the direct carbonation process are bleachers, dryers and predryers.
Emission ractors for the emission sources are presented in Table 5.16-1, and
emission factors for the Solvay process are presented In Table 5•16-2.
In addition to the najor emission points, emissions may also arise from
crushing and dissolving operations, elevators, conveyor transfer points,
product loading and storage piles. Emissions from these rources have not
buen quantified.
Particulate matter is the only pollutant of concern from sodium carbon-
ate plants. Emissions of sulfur dioxide (SC^) arise from calc'.nerp fired
with coal, but reaction of the evolved S02 with the sodium carbonate in the
calciner keeps SC>2 emissions low. Small amounts of volatile organic com-
pounds (VOC) may also b^ emitted frcm calciners, possibly from oil shale
associated with the trona ore, but thsse emissions have not been quantified.
The particulate matter emission rates fron calciners, dryers, predryers
and bleachers are affected by the gas velocity through the unit and by the
particle size distribution of the feed material. The latter affects the
emission rate because small particles are more easily entrained in a moving
stream of gab than are large particles. Gas velocity through the unit
affects th
-------
CO
co
KJ
L
n
fl>
yj. Or*
?*
-j
r;
O
•c
10
M
CL
c
L.
H
t
I
c"1"""0
,„,,,
-" I -"' I
t ' ^ ' ^
&-«. I "I 1
«~J lln "» 1 , 1 s ^ 1 . >
SrTr,^ I t*'cl"" I M««ol»iit -• Cr»til.'»rl '
Fit-ure j.16-1. Godi'jm carbonate productior by monohydrat
t T
| ss? | -, =r
" 4-,
•^ . .,) ^ ^ ^
C«.t.t.1 j
„-,„ |
I
_L
1>^T-' 1
e proces
t
Control
J ».... 1—
1 !
figure 5.16-2. SorUum rarbonate production by direct carbonation process,
-------
TABLE 5.16-1.
UNCONTROLLED EMISSION FACTORS FOR NATURAL PROCESS
SODIUM CARBONATE PLANTS3
EMISSION FACTOR RATING: B
Source
Particulate emissions
kg/Mj? Ib/ton
G&3 fired calciner ,
Coal fired calcln^r
p
Rotary steam t'jhe dryer
Fluid bed steam tube dryer
Rotary steam heater predrver
Rotary gas fired bleacher
184.0
195.0
33.0
73.0
1.0
155.0
368.0
390.0
67.0
146.0
3.1
311.0
-References 3-5 Values are averages of 2 - 3 test runs.
Factor ^.s in kg/Mg (Ib/ton) of ore fed to calciner. Includes particulate
emission? from coal fly ash. These represent < 1% of the total emissions.
Emissions of S02 from the coal are roughly 0.0007 kg/Mg (0.014 Ib/ton) of
ore feed.
.Factor is in kg/Mg (Ib/ton) of dry product from dryer.
Factor is in kg/Mg (Ib/ton) of dry NaHC03 feed.
Factor is in kg/Mg (Ib/ton) of dry feed to bleacher.
TABLE 5.16-2.
UNCONTROLLED F.1ISSION FACTORS FOR A SYNTHETIC
SODA ASH (SOLVAY) PLANT3
EMISSION FACTOR RATING: D
Emissions
Ammonia losses
Particulate0
kg/Mg
2
25
Ib/ton
4
50
.Reference 6.
Calculated by subtracting measured ammonia effluent discharges from ammonia
^purchases.
""Maximum uncontrolled emissions, from New York State process certificates to
operate. Does not include emissions from fugitive or external combustion
sources.
5.16-4
EMISSION FACTORS
8/82
-------
factor for coal fired calclners is about 6 percent higher than that for gas
fired calcine-s- r'luid bed steam tube dryers have higher gas flow rates and
particulate emission factors than do rotary steam tube dryers. No data on
uncontrolled particulate emissions from gas fired dryers are available, but
these dryers also have higher gas flow rates than do rotary steam tube
dryers and would probably have higher particulate emission factors.
The particulate emission factors presented in Table 5.16-1 represent
emissions measured at the inlet to the control devices. However, even in
the absence of air pollution regulations requiring emission control, these
emissions should be controlled to some degree to prevent excessive loss of
product. Because the level of control needed for product recovery is
difficult to define, the emission factors do not account for this recovery.
Cyclones In series with electrostatic preclpltators (E^P) are most
commonly used to control particulate emissions from calciners and bleachers.
Venturi scrubbers art also used, but they are not as effective. Cyclone/ESP
combinations have achieved removal efficiencies ranging from 99.5 to 99.96
percent for new coal fired calciners, and 99.99 percent for bleachers. Com-
parable efficiencies should be possible for new gas fired calciners. Venturi
scrubbers are most commonly used to control emissions from dryers and pre-
dryers, because of the high moisture content of the exit gas. Cyclones are
used in series with the scrubbers for predryers and fluid bed steam tube
dryers. Removal efficiencies averaging 99.88 percent have been achieved for
venturi acrubberr on rotary steam tube dryers at a pressure drop of 6.2 kPa
(25 inches water), and acceptable collection efficiences nay be achieved
with lower pressure drops. Efficiencies of 99.9 percent have been achieved
for a cyclone/venturi scrubber en a fluid bed steam tube dryer at a pressure
drop of 9.5 kPa (38 Inches water). Efficiencies over 98 percent have been
achieved for i. cyclone/venturi scrubber on a predryer.
Fugitive emissions originating from limestone handling/processing oper-
ations, produci: drying operations and dry solids handling (conveyance and
bulk loading; are a significant source of emissions from the manufacture of
soda ash by the Solvay process. These fugitive emissions have not been
quantified. Ammonia losses also occur because of leaks at pipe fittings,
gasket fla-iges, pump packing glands, discharges of absorber exhaust, and
exposed bicarbonate cake on filter wheels and on feed floor prior to
calcifying.
References for Section 5.15
I. Sodium Carbonate Industry - Background Informationfor Proposed
Standards, EPA-450/3-80-029a, U. S. Environmental Protection Agency,
Research Triangle Park, NC, August 1980.
2. Air Pollutant Emission Factors, Final Report, HEW Contract Number
CPA-22-69-119, Resources Research, Inc., Reston, VA, April 197!J.
3. Sodium Carbonate Manufacturing Plant, EPA-79-SOD-1, U. S. Environ-
mental Protection Agency, Research Triargle Park, NC, August 1979.
8/82 Chemical Process Industry 5.16-5
-------
4. Sodium Carbonate Manufacturing Plant, EPA-79-SOD-2, U. S. Environ-
mental Protection Agency, Research Triangle Park, NC, March 1980.
5. Particulate Emissions from the Kerr-McGee Chemical Corporation Sodium
Carbonate Plant. EPA-79-SOD-3, U. S. Environmental Protection Agency,
Research Triangle Park, NC, March 1980.
6. Written communication from W. S. Turetsky, Allied chemical Company,
Morristown, NJ, to Frank Noonan, U.S. Environmental Protection Agency,
Research Triangle Park, NC, June 17, 1982.
5-16-6 EMISSION FACTORS 8/82
-------
5.17 SULFUKIC ACID
5.17.1 General
All sulfuric acid Is made by either the lead chamber process
or the contact process. Because the contact process accounts for
more than 97 percent of the total sulfuric acid production In the
United States, it is the only process discussed in this Section.
Contact plants are generally classified according to the raw materials
charged to them - (1) elemental sulfur burning, (2) spent acid and
hydrogen sulfide burning, and (3) sulfide ores and smelter gas
burning. The contributions from these plants to ':he total acid
production are 68, 18.5 and 13.5 percent respectively.
All contact processes incorporate three basic operations, each
of which corresponds to a distinct chemical reaction. First, the
sulfur in the feedstock is burned to suitur dioxide:
S •«• 02 — ^- S02
Sulfur Oxygen Sulfur (1)
dioxide
Than, the sulfur dioxide is cacalytically oxidize 1 to sulfur trioxide:
2S02 + 02 — *> 2S03
Sulfur Oxygen Sulfur (2)
dioxide trioxide
Finally, the sultur trioxide is absorbed in a strong aqueous solution
of sulfuric acid:
S03 + H20 — *
Sulfur Water Sulfuric (3)
trioxide acid
Elemental Sulfur Burning Plants ' - Elemental sulfur, such as
Frasch process sulfur from oil refineries, is melted, settled or
filtered to renovL. ash and Is fed into a combustion chamber. The
sulfur is burned In clean air that has been dried by scrubbing with
93 - 99 percent sulfuric acid. The gases from the combustion chamber
cool and then enter the solid catalyst (vanadium pentoxide) con-
verter. Usually, 95 - 98 percent of the sulfur dioxide from the
combustion chamber is converted to sulfur trioxide, with an accompany
ing large evolution of heat. After being cooled, the converter exit
gas enters an absorption tower, where the sulfur trioxide is absorbed
with 98 - 99 percent sulfuric acid. The sulfur trioxide combines
with the water in the acid and forms more sulfuric acid.
If oleum, a solution of uncombined 803 in HjSO^, Is produced,
SOj from thft converter ia first passed to an oleum tower that is
fed with 98 percent acid from the absorption system. The gases
4/81 Chemical Process Industry 5.17-1
-------
-J
t'-J
rr
^
S7i
O
O
72
(S)
STEAM DRUM
BLOI
s
BLOWER
LIQUID
SULFUR'
1 U
DRYING
TOWER
JU ISULFUR
koRAGr^ PU«P
" M, ; -
FURNACE
TT
ACID 1 '•
COOLER t — "^
uuinniim, \
-O -- O
miiiiiimui
-O- - O
my////////
STEAM
TO
I ATMOSPHERE
BOILER
BOILtR
CONVLRTER
BOILER FEED WATER-
3L
ECONOMIZER
ABSORPTtOI
TCWER
•WATER
AGIO
COOLER
ACID PUMP
TANK
-*~ PRODUCT
Figure 5.17-1. Basic How diagram of contad process sullui'ic acid plan: burri'ng elemental sullur.
-------
-SPENT AGIO
•SULFUR
ELECTROSTATIC
PRECIPITATDRS .
I AJ A _l I » J
[_ 58% ACID _J
PUMP TANK
1
-£~7i
C "
ZT~ ZT
c " '
., ACID COOLERS )
C 1^-
3l J
PRODUCT-
* COOLER
•PRODUCT dl
93^. ACID
' PUMP TANK"
Figure 5.17-2. Basic flow diagram of contact process sulfu.ic acid plant ouining spent acid.
4/81
Chcniic.il Process huliislrv
5.17-3
-------
from the oleum tower arc then pumped to the absorption column where
the residual sulfur trioxlde Is removed.
A schematic diagram of a contact process sulfuric acid plant
that burns elemental sulfur is shown in Figure 5.17-1.
1 2
Spent Acid and Hydrogen Sulfide Burning Plants ' - Two types of
plants are used to process this type of sulfuric acid. In one, the
sulfur dioxide an I other combustion products from the combustion of
spent acid and/or hydrogen sulfide with undried atmospheric air are
passed through gat cltaning and mist removal equipment. The. gas
stream next passes through a drying tower, k blower draws the gas
from the drying tower and discharges the sulfur dioxide gas to the
sulfur trloxide coiverter. A schematic diagram of a contact process
sulfuric acid plant that burns spent acid is shown In Figure 5.17-2.
In a "wet gas j.lant", the wet gases from the combustion chamber
are charged directly to the converter with nc intermediate treatment.
The gas from the converter flews to the absorber, through which
93 - 93 percent sulfi ric acid Is circulating.
Sulfide Ores and Sraelver Gas Plants - The configuration of this
type of plant Is essentially the same as that of a spent acid plant
(Figure 5.17-2), with the primary exception that a roaster is used
In place of the combustion furnace.
The feed used in these *.>lants is smelter gas, available from
such equipment as copper converters, reverberatory furnaces,
roasters and flash smelters. The sulfur dioxide in the gas is con-
taminated with dust, ac'd mist and gaseous Impurities. To remove
the impurities, the gases must be cooled and passed through purifi-
cation equipment consisting of cyclone dust collectors, electrostatic
dust and mist precipitators, and scrubbing and gas coaling towers.
After the gases are cleaned and the excess water vapor is removed,
they are scrubbed with 98 percent acid in a drying tower. Beginning
with the drying tower stage, these plants are nearly identical to
the elemental sulfur plants shown in Figure 5.17-1.
5.17.2 Emissions and Controls
Sulfur Dioxide ~ - Nearly all sulfur dioxide emissions from
sulfuric acid plants ar<>. found In the exit gases. Extensive testing
has shown that the mass of these SO2 emissions is an inverse furc-
tion of the sulfur conversion efficiency (S02 oxidized to 803).
This conversion is always Incomplete, and is affected by the number
of stages in the catalytic converter, the amount of catalyst used,
temperature and pressure, and the concentrations of the reactants
(sult'ui' dioxide and oxygen). For example, if the inlet S02 concen-
tration to the converter were 8 percent by volume (a representative
value), and Lie conversion teraperatuue were 473°C (883°F), the con-
version efficiency would be 96 percent. At this conversion, the
5.17-4 EMISSION FAC10RS 4/81
-------
uncontrolled emission factor for 502 would be 27.5 kg/Mg (55 pounds
per ton) of 100 percent sulfurlc acid produced, as shown in
Table 5.17-1. For purposes of comparison, note that the Environ-
mental Protection Agency performance standard for new and modified
plants Is 2 l-.g/Mg (4 pounds per ton) of 100 percent acid produced,
maximum 2 hour average.-^ As Table 5.17-1 and Figure 5.17-3 indicate,
.achieving this standard requires a conversion efficiency of 99.7
percent in an uncontrolled plant or the equivalent S02 collec-
tion mechanism in A controlled facility. Most single absorption
plants have SO conversion efficiencies ranging from 95 - 98 percent.
In addition to exit gases, small quantities of sulfur oxides
are emitted from storage tank vents and tank car and tjink truck vents
during loading operations, from suIfuric acid concentrators, and
through leaks In process equipment. Few data are available on the
quantity of emissions from these sources.
Of the many chemical and physical means for removing SO2 from
gas streima, only the dual absorption and the sodium sulfite/bisul-
fite scrubbing processes have been found to increase acid production
without yielding unwanted byproducts.
TABIE 5.17-1. EMISSION FACTORS FOR SULFURIC
ACID PIANTS*
EMISSION FACTOR RATING: A
S09 Emissions
Conversion of S02 kg/Mg of 100% Ib/ton of 100%
to S03 (%) H2S04 H2SO^
93
94
95
96
97
93
99
99.5
99.7
100
43.0
41.0
35.0
27.5
20.0
13.0
7.0
3.5
2.0
0.0
96
82
70
55
40
26
14
7
4
0
.Reference 1.
This linear interpolation formula can be used for calculating
emission factors for conversion efficiencies between 93 and 100%:
emission factor --13.65 (% conversion efficiency) + 1365.
4/81 Chemical Process Industry 5.17-5
-------
99.S2
10,000
SULFUR CONVERSION, % fNdstodi sulkr
99.7 99.0
97.0 96.0 95.0 92.9
190
1.S 2 2.S 3
4 S « 7 i 9 ID IS 20 ?5 30 40 50 60 70 80 90100
SOjENBSIONS, Ib, ton o( 100'. H2$0,< product
Figure 5.17-3. Sulfuric acid plant feedstock sulfur conversion versus volumetric and
mass SC>2 emissions at varicjs inlet S02 cnncBntration.s by volume.
5.17-6
EMISSION FACTORS
4/81
-------
In the dual absorption process, the SO-j gas formed la the
primary converter stages is sent to a primary absorption tower wheie
most of the 803 is removed to form V^SO^. The remaining unconverted
sulfur dioxide is forwarded to the final stages in the converter to
remove much of the remaining SC>2 by oxidation to SO-j, from whence
it Is sent to the secondary absorber for final sulfur trioxide
removal. The result is th^ conversion of a auch higher fraction of
S02 to SO-j (a conversion of 99.7 percent or Higher, on the average,
which meets the performance standard). Furthermore, dual absorption
permits higher converter inlet sulfur dioxide concentrations than
are used ia single absorption plants, because the secondary conver-
sion stages effectively remove any residual sulfur dioxide from the
primary absorber.
Where dual absorption reduces sulfur dioxide emissions by
Increasing the overall conversion efficiency, the sodium sulfite/
bisulfite scrubbing process removes sulfur dioxide directly from
the absorber exit gabcs. In cne version of this process, the sul-
fer dioxide in the waste gas is absorbed in a sodium anlfite solution,
if- .eparated, and Is recycled to the plant. Test results from a
68c Mg (750 ton per day) plant equipped with a sulfite scrubbing
system indicated an average SO,, emission factor of 1.35 kg/Kg
(2.7 pounds per ton) of 100 percent acl4.
Acid Mist - Nearly all the acid mist emitted from sulfurlc acid
manufacturing can be traced to the absorber exit gases. Acid mist
Is created when sulfur tiioxide combines with water vapor at a
temperature below the dew point of sulfur trioxide. Once formed
within the process system, this iiist is so stable that only a small
quantity can be removed in the absorber.
In general, the quantity and particle size distribution of
acid mist are dependent on the type of sulfur feedstock used, the
strength of acid produced, and the conditions in the absorber.
Because it contains virtually no water vapor, bright elemental
sulfur produces little acid mist vrhen burned. However, the hydro-
carbon impurities in other feedstocks - dark sulfur, spent acid
and hydrogen si'lfide - oxidise to water vapov during combustion.
The water vapo»., in turn, combines with sulfur trioxide as che gas
coole in the Eystem.
The strength of acid produced - whether oleum or 99 percent
sulfuric acid - also affects mist emissions. Oleum nlants produce
greater quantities of finer more stable mist. For example, uncon-
trolled mist emissions from oleuzi plants* burning spent acid range
from 0.5 to 5.0 kg/Mg (1.0 to 10.0 pounds per ton), while those
from 98 percent acid plants burning elemental sulfur range from
0.2 to 2.0 kg/Mg (0.4 to 4.0 pounds per ton). Furthermore,
85 - 95 weight percent of the. mist particles from oleum plants are
less than 2 microns in diameter, compared with only 30 weight
percent that are less than 2 microns in diameter from 98 percent
acid plants.
4/81 Chemical Process Industry 5.17-7
-------
The operating temperature of the absorption column directly
affects sulfur trioxide absorption and, accordingly, the quality of
acid mist formed after exit gases leave the stack. The optimum
absorber operating temperature depends on the strength of the acid
produced, throughput rates, inlet sulfur trioxide concentration!),
and othev variables peculiar to each individual plant. Finally,
it should be emphasized that the percentage conversion of sulfur
trioxide has no direct effect on acid mist emissions. In
Table 5.17-2, uncontrolled acid mist eclssions are presented for
various suituric acid plants.
TABLE 5.17-2. ACID MIST EMISSION FACTORS FOR SULFURIC
ACID PIANTS WITHOUT CONTROLS8
EMISSIONS FACTOR RATING: D
Emissions
Raw material
Recovered sulfur
Bright virgin sulfur
Dark virgin sulfur
Sulfide ores
Spent acid
uieuia yruuuteu,
X votal output
0 to 43
0
33 to 100
0 to 25
0 to 77
kg/Mg acid
0.175 - 0.4
0.85
0.16 - 3.15
0.6 - 3.7
1.1 - 1.2
Ib/ton acid
0.35 - 0.8
1.7
0.32 - 6.3
1.2 - 7.4
2.7 - 2.4
.Reference 1.
product. Use low end of ranges for low oleum percentage and high
end of ranges for high oleum percentage.
Two basic types of devices, electrostatic precipltators and
fiber mist eliminators, effectively reduce the acid mist concentra-
tion from contact plants to less than the EPA New Source Performance
Standard, which is 0.075 kg/Mg (0.15 pound per ton) of acid. Pre-
clpitatora, if properly maintained, are effective In collecting the
mist particles at efficiencies up to 99 percent (see Table 5.L7-3).
The three moat conmonly used fiber raiet eliminators art the
vertical tube, vertical panel, and horizontal dual pad types. They
differ from one another in t»e arrangement of the fiber elements,
which are composed of either chemically resistant glass or fluoro-
carbon, and in the means employed to collect the trapped liquid,
The operating characteristics of these thre<> types are compared with
•lectrostatic precipita,oro in Table 5.17-3.
5.17-8
EMISSION FACTORS
4/81
-------
TABIE 0.17-3. EMISSION COMPARISON AND COLLECTION EFFICIENCY OF
TYPICAL ELECTROSTATIC PRECIPITATOR AND FIBER MIST ELIMINATOR0*
Particle size
collection
efficiency, %
Control device
Electrostatic
precipitator
Fiber miat
elirainator
Tabular
Panel
Dval pad
>3 (.m
99
100
100
100
<;3,ira
100
95-99
90-98
93-99
Aci.j mist amiss iona
V.
98X acid plants"
kg/Mg
0.05
0.01
0.05
0.055
lb/ton
C.IO
0.02
0.10
(J.ll
Oleum pi
kg/Mg
0.06
0.01
0.05
0.055
lb/ton
0.12
0,02
0.10
0.11
^Reference 2.
Eased on manufacturers' generally expected results. Calculated for 8Z
SO concentration in
converter.
References for Section 5.17
1 . Atmospheric Emission; i rom Sulfuric Acid Manufacturing Processes,
999-AP-13, U.S. Department ot Health, Education an<" Welfare,
Wa-iMngton, DC, 1966.
2. Unpublished r«jporf. on control of air oollution from Huli'uri>:
acid plants, U.S. Environmental frotectj.cn Agency, Research
Triangle fir'-, NC, August 1971.
3. Standards of Performance for New Stationary Sources. 36 FR 24875,
December 23, 19."..
4. M. Drabkin and Kathryn J. Brooks, A Review of Standards of
Performance for New Stationary Sources - Sulfuric Acid Plants.
tiPA Contract No. 68-02-2526, Mitr*> Corporation, McLean, VA,
June 197«).
^ • Final Guideline Docament: Ccntrol oi Sulfuric Acid Hist
Emissions f run: ExJ tit ing Sul_f_uric__Ac_id Product ion Units,
EPA 450/2-77--019, U.S. Environmental Protection Agency,
Research Triangle Park, NC, September 1977.
4/81
Chptnical Process Industry
5.17-9
-------
5.18 SULFUR RECOVERY
1 2
5.18.1 Process Description '
Most of the elemental sulfur produced from hydrogen sulfide (H2S)
is made by the modified Claus process. A simplified flow diagram of
this process is shown in Figure 5.18-1. The process consists of the
multistage catalytic oxidation of hydrogen sulfide according to the
following overall Reaction:
2H:>3 + 02 -> 2S + 2H2U (L)
In the tirst step, one third of the H2S is reacted with air in a furnace
and combusLeu to !>02 according tc Reaction (2):
H2!J + 1.502 •+ S02 + H20 (2)
The heat of the reaction is recovered in a waste heat boiler or sulfur
condenser.
For gas streams with low concentrations of H2S (20 - 60X), approxi-
mately one third of the gas stream is fed to the furnace and the H2S is
nearly completely combusted to S02, while the remainder of the gas is
bypassed around the furnace. This is the "split stream" configuration.
For gas streams with higher H2S concentrations, the entire gas stream is
fed to the furnace with just enough air to combust one third of the H2S
to S02. This is the "partial combustion" configuration. In this
configuration, as much as 50 to 60 percent conversion of the hydrogen
sulfide to elemental sulfur rakes place in the initial reaction chamber
by Reaction (1). In extremely low concentrations of H2S (<25 - 30%), a
Glaus process variation known as "sulfur recycle" may be used, where
product sulfur is recycled to the furnace and burned, raising the
effective sulfur level where flame stability may be maintained in the
furnaces.
Aftcir the reaction furnace, the gases are cooled to remove
elemental sulfur and then reheated. The remaining H2S in the gas stream
is then reacted with the S02 over a bauxite catalyst at 500 - 600°F
(260 - 316°C) to produce elemental sulfur according to Reaction 3:
2H2S + S02 j 3S + 2H20 (3)
Because this is a reversible reaction, equilibrium requirements limit
the conversion. Lower temperatures favor elemental sulfur formation,
tut at too low a temperature, elemental sulfur fouls the catalyst.
Because the react'.on is exothermic, the conversion attainable in one
stage I." limited. Therefore, two or more stages are used in series,
vith interstage cooling to remove the heat of reaction and to condense
the sulfur.
2/ttO Chi-Miical l'rn«-» Indn-lr*
-------
•£
***
>
SULFUR
CONDENSER
SOIICI LINES IND'CATE FLOW
FOR PAHTIAL COMBUSTION PROCESS
com IOUHAIIOM
UASHbU LIML :r. J,C*lLii AUU1IIONAL
STWEA".' KREiLWl IK IIIL iPLII
HBOCL.OC CUNf IGUHA I IUN
ADDITIONAL CONVEF>lEnS/CCinb[NsCH',
ro ACHIEVE ACOinotAL nEcovtsy or
H_tUlNT\L SULFUM .HE OPTIONAL AT
TMii POlMf
3UIFUR
CONDErnSEH
^
i At. OAI
c w
g
SPLNl CATAirST
Figure 5.18-1. Typical How diagram Claus Process sulfur recovery.
-------
Carbonyl sulfide (.COS) and carbon diaulfide (CS2) are formed in the
reaction furnace In thj presence of carbon dioxide and hydrocarbons:
C02 + H2S J H20 + COS (4)
COS + H2S J H20 + CS2 (5)
CHi, + 4G + CS2 i- 2HiS (6)
About 0.25 to 2.5 percent of the sulfur fed may be lost in this way.
Additional sulfur may be lost as vapor, mist or droplets.
5.18.2 Emissions and Controls
Tail gas from a LLaus sulfur recovery unit contains a variety of
pollutants, including sulfur nioxide, hydrogen sulfide, other reduced
sulfur compounds (such as COS and CS2), carbon monoxide, and volatile
organic conpounde. If no other controls are used, the tail <*as is
incinerated, so that rl..i emissions consist mostly of aulrur dioxide.
Smaller f.mounts of carbon monoxide are also emitted.
The emissions of SO^ (along with H2S and sulfur vapor) depend
directly on the aulfur recovery efficiency of the Clnua plant. This
efficiency Is dependent upon many factors, including the following:
- Nunber of catalytic conversion stages
- Inlet feed stream composition
- Operating temperatures and catalyst maintenance
- Maintenance of the proper stolchionetric ratio of H2S/S02
- Operating capacity factor
Recovery efficiency Increases with the number of catalytic stages
used. For example, for a Claus plant fed with 90 percent H2S, sulfur
recovery Is approximately 85 percent for one catalytic stage and 95
percent for two or three stages.
Recovery efficiency also depends on the inlet feed stream compo-
sition. Sulfur recovery Increases with increasing H2S concentration in
the feed stream. For example, a plant having twc or three catalytic
stages would have a sulfur recovery efficiency of approximately 90
percent when treating a 15 mole percent H2S feed stream, 93 percent for
a 50 mole percent H2S stream, and 95 percent for a 90 mole percent H2S
stream. Various contaminants In the feed gas reduce Cj.aus sulfur
recovery efficiency. Organic compounds in the .feed require extra air
for combustion, and added water and inert gas from burning these organics
decrease sulfur concentrations and thus Ijwer sulfur recovery. Higher
molecular weight organics also reduce efficiencies because of soot
formation on the catalyst. High concentrations of C02 in the feed gas
reduce catalyst life.
2/BO rin'niiriil TrcHT*!* lnHtictr\ 3.18-3
-------
Since the Glaus reactions are exothermic, sulfur recovery is
enhanced by removing heat and operating the reactors at as low a tem-
perature as practicable- without condensing sulfur on the catalyst.
kacovery efficiency also depends on catalyst performance. Chie tu 2
percent loss in recovery efficiency over the period of catalyst life has
been reported. Maintenance of the 2:1 stolchiometric ratio of H2S and
S02 is essential for efficient sulfur recovery. Deviation ibove or
below this ratio results in a loss of efficiency. Operation of a Claus
plant below capacity may also impair Claus efficiency somewhat.
Removal of sulfur compounds from Claus plant tail gas is possible
Vy three general schemes:
1) Extension -?f the Claus reaction to increase overall sulfur
recovery,
2) Conversion of sulfur gases to S02 , followed by S(>2 removal
technology,
3) Conversion of sulfur gases to l^S, followed by I^S removal
technology.
Processes in the first scheme rencve additional sulfur compounds by
carrying out "he Claus reaction at lower temperatures to shift equi-
librium of the Claus reactions toward formation of additional sulfur.
The IFP-1, BSR/Selectox. Sulfreen, and Amoco CBA processes use this
tejunique to reduce the concentration of tail gas sulfur compounds to
1500 - 250U ppm, thus increasing the sulfur recovery of the Claus plant
to 99 percent.
In the second class of processes, the tail gas is incinerated Co
convert all sulfur compounds to SOj. The f-02 is than recovered by one
of several processes, such AS the Wellman-U/rd. In the Wellman-Lord and
certain other processes, the S0;> absorbed from the tail gas is recycled
to the Claus plant to recover additional sulfur. Processes in this
class can reduce the concentration of sulfjr compounds in the tail gas
to 200 - 300 ppm or leas, for an overall sulfur recovery efficiency
(including the Claus plant) of 99.9+ percept.
The third method for removal of sulfur .-.ompounds from Claus tail
gas involves converting the sulfur compounds to H2S by mixing the tail
gas wirh a reducing gas and passing it over a reducing catalyst. The
H2S ic then removed, by the Stretford process (ir. the Beavon and Clean
Air pror.fisses) or by an amine absorption systen. (SCOT process). The
Beavon and Clean Air processes recover the HaS ns elemental sulfur, and
the SCOT process produces a concentrated I^S stream which is recycled to
the Claus process. These processes reduce the concentration of sulfur
compounds in the tail gas to 200 - 300 ppm or less and increase the
overall recovery efficiency of the Claus plant to 99.9+ percent.
. IK-I EMISSION FACTORS 2/HO
-------
A New Source Performance Standard for Glaus sulfur recover} plants
in petroleum refineries was promulgated in March 1978. This standard
limits emissions to 0.025 percent by volume (250 ppm) of S02 on a dry
basis and at zero percent oxygen, or 0.001 percent by volume of H2S and
I'.? 3 percent by volume of H2S, COS, and CS2 on a dry basis and at zero
percent oxygen.
Table 5.18-1.
EMISSJUN FACTORS FOR MODIFIED GLAUS SULFUR RECOVERY
PLANTS
EMISSION FACTOR RATING:
Number of Catalytic Stages
Two, uncontrolled
Three, uncontrolled
Four, uncontrolled
Contr illedc
Typical
Recovery
of Sulfur, %a
92 to 95
95 to 97.5
96 to 99
99 to 99.9
SO, Emissions
Ib/ton
348 to 211
211 to 167
167 to 124
40 to 4
kR/MT
174 to 105
106 to 84
84 to 62
20 to 2
Efficiencies are for feed gas streams with high H2S concentrations.
Gases wi.h lower H2S concentrations would hove lower efficiencies.
For example, a 2 or 3 stage plant could have a recovery efficiency of
95% Lor a 90% H2S stream, 93% for 50% H2S, and 90% for 15% 1I2S.
Based on net weight of pura sulfur produced. The range in emission
fractors corresponds to the range in percentage recovery of sulfur.
SOj emissions calculated from percent..^e sulfur recovery by following
equation:
S02 emissions (kg/MT)
X 2000
(lQO-% recovery)
% recovery
Q
Lower percent recovery is for control by extended Claus, and higher
percent-, is for conversion to and removal of H2S or SOj.
Peferences for Section 5.18
1.
2.
3.
E. C. Cavanaugh, e t al., Environmental Assessment Data Base for
Law/Medium Btu Gasification TechnologyfVolumeIT. EPA Contract No.
68-02-2147, Radian Corporation, Austin, TX, September 1977.
StandardsSupport and Environmental Impact Statfeirent, Volume 1:
Proposed Standards of Performancefor Petroleum Refinery Sulfur
Recovery Plants. EPA-450/2-76-016a, U. S. Environmental Protection
Agency, Research Triangle Park, NC, September 1Q76.
B. Goar and T. Arrington, "Guidelines for Handling Sour Gas",
Cil and Gas Journal. 76(26): 160-164, June 26, 1978.
2/HO
( .liriiiiral
i lmln«|rv
5. IH-.l
-------
S. 19 SYNTHETIC FIBERS
S. 19.1 Process Description'
Symbolic fibers are thjsified into t\*o imjor categories, semi-synthetic and "true" synthetic. Semi-synthetics.
such as viscose ray on and acetate t'ibcis. result when natural polymeric materials such as cellulose are brought into
J dissolved ur dispersed slate and then spun into fine filaments. True synthetic polymers, such as Nylon, * Orion.
Jiij D.KIOII. result from addition and other polyrneri/ation reactions thai fonn long chain molecules.
True sviiihctic fibers begin with (he preparation of extremely long, chain-like molecules. The polymer is spun
in one of four ways:- (1) melt spinning, in which molten polymer is pumped through spinneret jell, the polymer
solidifying js it strikes the cool air; (2) dry spinning, in which the polymer is dissolved in a tuliable oiganic
solvent, and the resulting solution is forced through spinnerets: (3) wet spinning, in which the solution Is
coagulated in a chemical a» it emerges from the spinneret: anJ (4) core spinning, the newest method, in which a
continuous filamer-t ; irn together with short-length "hard" fibers is introduced onto a spinning frame in such a
way as to form a composite yarn.
5.19.2 Emissions and Controls1
In the manufacture of viscose rayon, carbon disulfiae and hydrogen sulfidc are the major gaseous emissions.
Air pollution controls arc not normally used to reduce these emissions, but adsorption in activated carbon at an
efficiency of 80 tn 95 percent, with subsequent recover) of theCS-i can be accomplished.^ Emissions of gaseous
hydrocarbons may also occur from the diying of the finished fiber, Table 5.10-1 presents emission factors for
semi-synthetic and true synthetic fibers.
Table 5.19-1. EMISSION FACTORS FOR SYNTHETIC Fl 3ERS MANUFACTURING
EMISSION FACTOR RATING: :
Type of fiber
Semi synthetic
Viscose rayona-b
True synthetic11
Nylon
Dacron
Hydrocarbons
Ib/ton ; kg/MT
7
3.5
_
Carbon Hydrogen
disulfide ' suHide
Ib/ton 1 kg/Ml ! Ib/ton
55
27.5
6
kg/MT
3
OH vapor
or mist
" lb/:on
15
-t
kg/MT
7.5
3.5
'Reference A
bMay be reduced by 80 to 95 percent adsorption in activated char-oal •
"-Reference 5
•Mention of company or product names dres not constitn'e ,«ndv,r-sement by the Environmental Protection
Agency
2/72
Chemical Process Industry
5.19 1
-------
References for Section 5.19
I. Air Polh'tmt Emission Factors. Final Report. Resources Research, Inc. Reston, Va. Prepared fo; National
Air Pollution Control Administration Durham, N.C., under Contract Numbci CPA-22-69-119. April 1970
2. Fibers, M in-Made. In: Kirk-Othmer Encyclopedia of Chemical Technology. New York, John Wiley and Sons.
Inc. 1969.
3 Fluidized lUcovery System NabsCarbon Pisulllde. Chem. Kng. 70(«):92-94. April 15,1963.
4. Private communication between Resources Research. Incorporated, and Rayon Manufacturing Panf.
Decembu 1969.
5. Private communication between Resourjes Research, Incorporated, and L.l. Dupoul dc Nemours 2nd
Company. Jar uary 13,1970.
5.19-2 EMISSION FACTORS 2/72
-------
5.20 SYNTHETIC RUBBER
5.20.1. Emulsion Styrene-Butadiene Copolymers
General - Two types of polymerization reaction are used to produce styrene-
butadiene copolymors, the emulsicn type and the solution type. This Section
addresses volatile organic compound (VOC) emissions from *-.he manufacture of
copolymers of styrene and butadiene made by emulsion polymerization processes.
The emulsicn products can ' e sold in either a granular solid form, known as
crumb, or in a liquid form, known as latex.
Copolyraers of styrene and butadiene can be wade with properties rang \.n?
froir those of a rubbery material to those of a very resilient plastic.
Copolymers containing less than 45 weight percent styrene are known as
styrene-butadiene rubber (SBR). As the styrene content is incraased over 45
weight percent, the product becomes increasingly more plastic.
Ec.ul.jion Crumb Process - As shown in Figure 5.20-1, fresh styrene and
bu:adiene are piped separately to the manufacturing plant from the storage
area. Polymerization of styrene and butadiene proceeds continuously fhough
a iirain of reactors, with a residence time in each reacfcr of approximately
1 hour. The reaction product formed in the emulsion pha'ja of the reaction
mixture is a milky white emulsion called latex. The overall polymerization
reaction ordinarily is not carried out beyond a 60 percent conversion of
monomers to polymer, because the reaction rate falls off considerably beyond
this point and product quality begins to deteriorate.
Because recovery of the unres.cted mcnomers and their subsequent purifi-
cation art essential to economical operation, unreacted outadie.ie and styrene
from the emulsion crun.b polymerization process normally are recovered. The
latex emulsion is introduced to flash tanks where, usin£ vacuum flashing, the
unreacted butadiene is removed. The butadiene is then compressed, condensed
and pumped back to the tank farm storage area for subsequent reuse. The
condenser tail gases and noacondensibles pass through a butaciiene adsorber/
desorber uni:, where more butadiene is recovered. Sor.e nonccTdensibles ami
VOC vapors pass to the atmosphere or, at some plants, to a f Lire system.
The latex stream from the butadiene recovery area Is then sent to the styrene
recovery process, usually taking place in. perforated plate steam stripping
columns. From the styrem stripper, the latex is stored in blend tanks.
From this point in the manufacturing process, latex is processed
continuously. The latex is pumped from the bl<:nd tanks to coagulation
vessels, where dilute sulfur!' aci.- (l^SO^ of pH 4 to 4.5) and sodium
chloride solution are added. The acid and l.rin*» mixture causes the emulsion
to break, releasing th
-------
l/l
fo
o
m
V)
tn
hi
i
q
o
vTe 5.20-1. Typical process for crumb production by emulsion polymerization.
oo
-^.
00
-------
00
00
ro
O
"0
i
O
f>
re
M
CO
3
CL
e
tn
'ri-4..! X /
SJIt»«VMIB \ /
K>
O
I
Figure 5.20-2. Typical process for latex production by emulsion polymerization.
-------
TABLE 5.20-1. EMISSION FACTORS FOR EMULSION STYRENE-BUTADIENE
COPOLYMER PRODUCTION8
EMISSION FACTOR RATING: B
Process Volatile Organic Emissions
g/kg lb/ton
Emjlsion Crumb
£
Monomer recovery, uncontrolled 2.6 5.2
Absorber vent rf 0.26 0.52
Blend/coagulation tank, uncontrolled 0.42 0.84
Drverse 2.51 5.02
Emulsion Latex
Monomer removal _„
Condenser ventL
Blend tanks
Uncontrolled
8.45
0.1
16.9
0.2
Nonmethane VOC, mainly styrene and butadiene. For emulsion crinr-h and
emulsion latex processes only. Factors for related equipment and
operations (storage, fugitives, boilers, etc.) are presented in other
Sections of AP-42.
Expressed as units per unit of copolymer produced.
.Average of 3 industry supplied stack tests.
Average of 1 industry stack test ani 2 industry supplied emission
estimates.
No controls available. Average of _> industry supplied stack tests and 1
industry estimate.
EPA estimates from industry supplied data, confirmed by industry.
Leaving the coagulation process, the crumb and brine acid slurry is
separated by screens* Into solid and liquid. The crumb product is processed
in rotary presses that squeeze out most of the entrained water. The liquid
(bri.if /acid) from the screening area and the rotary presses is cycled to the
coagulation ar-ia for reuse.
The partially dried crumb is then processed In a continuous belt dryer
which hlcws hot ->ir at approximately 93°C (200°FJ across the crumb to com-
plete the drying of the product. Some plants have installed single pass
dryers, where space permits, but most plants still use the triple p?ss dryers
which vp-f literal led as original equipment in the 1940s. The dried product
is !,alrd cinrt writhed beforn shipment.
Latex Process - Emulsion polymerization can also be uced to
produce latex products. These latex propers have a wider range >'.f pro-
perties and uses than do the crumb nro-'ucts, but the plants are usually much
smaller- T vjex production, shown ir Figure 5.20-2, follows the same basic
processing steps as emulsion crvnrl/ oolyuierization, with the excep*io .1 of
final product processing.
5.20-4 EMISSION FACTORS 8/82
-------
As in emulsion crumb polymerization, the monomers are piped to the
processing plant from the storage area. The polymerization reaction is
taken to near completion (98 to 99 percent conversion), a:id the recovery of
unreacted monomers is therefore uneconomical. Process economy is directed
towards maxiuciii conversion of the monoirers in one process trip.
Because Tiost emulsion latex polymerization is done in a batch process,
the number of reactors used for latex production is usually smaller than for
;rum production. The latex is sent to a blowdown tank where, under vacuum,
iny unreacted butadiene and some unreacted styrene are removed from the
latex. If the unreacted styrune content of the latex has not heen reduced
sufficiently to meet product specifications in the blowdown step, the latex
is introduced to a series of steam stripping steps to reduce the content
further. Anv steam and styrene vapor from these sirip-.ing steps is taken
overhead and is sent to a water cooled condenser. Any uncondensibles leaving
the condenser are vented to the atmosphere.
After discharge from the blowdown tank or the. styrene stripper, the
latex is stored in process tanks, Stripped latex is passed through a series
of screen filters to remove unwanted solids and is stored in blending tanks,
where antioxidants are added and mixed. Finally, latax is pumped from rhe
bler.ding tanks to be packaged into drums or to be bulk loaded into railcars
or tank trucks.
Emissions qnd Controls - Emission factors for emulsion styrene-butadiene
copolyraer production processes are presented in Table 5.20-1.
In the emulsion crumb process, uncontrolled noncondensed tail gases
(VOC) pass through a butadiene absorber control device, which is 90 percent
affi' leut, to the atirosphere or, in some plants, to a flare stack.
No controls are presently employed for t.lie blend tank and/or coagul-
ation tank areas, on either crumb or latex facilities. Einissioi '"rora
dryers in the .:rurab process and the monomer removal part of the i.itex
process do not employ control devices.
Individual plant emissions may vary from the average values listed in
Table 5.20-1 with facility age, size and plant modification factors.
References t-^r Section 5.20
1. Control Techniques Guideline (Draft). EPA Contract No. (8-';2-3L68,
GCA, Inc., Chapel Hill, NC, April 1981.
2. Emulsion Styrene-Butadiene Copolymerg; Background Document , EPA
Contract No. 68-02-3063, TRW Inc., Research Triangle Park, NC, May 1981.
3. Confidential written communication from C. Fabian, U.S. Environmental
Protection Agency, Research Triangle Park, NC, to Styrene-Butadiene
Rubber File (76/lJ>B), July 16, 1981.
8/82 Chemical Process Industry 5 20-5
-------
5.21 Terephthalic Acid
5.21.1 Process Description
Terephthalic acid (TPA) is made by air oxidation of £-xy1ene .ind requires
purification for use in polyester fiber manufacture. A typical continuous
process for the manufacture of crude tcrephthalic acid (C-TPA) is shown i.i
Figure *>.21-1. The oxidation and product recovery portion essentially
consists of ;he Mid-Century oxidation process, whereas the recovery and
recycle of acetic acid and recovery of methyl acetate .ire essentially as
practiced by dimethyl terephthalate (D.'iT) technology. The purpose of the
DMT process is to convert the tereph thai ic. acid contained in C-TPA to a form
that will permit its separation from impurities. (,-TPA is extremely insoluble
in both water and most common organic solvents. Additionally, it does not
melt, it sublimes. Soae products of partial oxlil-ition of jv-xylene, such as
p-tolulc ~cid and jj-^oitnyl benzoir acid, appear as Impurities i.i TPA.
Methyl acetate is also formed in significant amounts in the reaction.
0 0
OCAT I' /—V II
CHj * 302 -» HO-C-/ VC—OH + 2H20
wutin.rn.iu ^ '
SOLVENT) (p-XYLENEi (AIR) \^ (TEREPHTHALIC ACID) (WATER)
CO + C02 + H20
(MINOR REACTION)' (CARBON (CARBON (WATER)
MONOXIDE) DIOXIDE)
C-TPAProduction
Oxidation of £-xylene - Pj-xylene (stream 1 of Figure 5.21-1), fresh acetic
ncid (2), a catUyst system, sur.h as manganese or cobalt acetate and sodium
bromide (3), and recovered acetic acid are combiner, into tue liT'.lt? teed
entering the reactor (5), At*- (6), compressed to t. reaction pressure of
about 2000 kPa (290 psi), is fed LG the r=actor. "he temperature of the
er.othermic reaction is maintained at about 200°C (i92°F) bv c-ntrolling the
pressure at which the reaction mixture is permittee to boil ano form the
vapor stream leaving the* reactor (7).
I.iert gases, excess oxyge.., CO, C02, and volatile organic compounds
(VOC) (8) leave the gaa/liquid separator and are sent t-> the high pr^asurt
aoaorber. Thiq stream is scrubbed wich tfater unrer pressure, tosulting in A
gas stream (9) of reduced VOC conrent. Part of the discharge from the
high pressure absorber is dried and is ujed as a aotvce of Ir.e.-t gas (TG),
and the remainder is passed through a pressure cort?-ol valve ana a a^ise
silencer before being discnarged to the atmosphere through process vent A.
The underflow (23) ftore the absorber is sent to the azeotrope still for
recovery of acetic acid.
Crystallization and Se^aratt.on - Thu reactor liquid containing TPA (10)
flows to a series of cryst-'jllizer.s, where the pressure is relieved und tha
5/P3 Chemical Process Industry 5.21-1
-------
c:
z;
n
H
o
oo
UJ
Figure 5.21-1. Crude Terephthalic Acid Proceee.
-------
liquid is cooled by the vaporization and return of condensed VUC and water.
The partially oxidized impurities are more soluble in act-tic acid arid tend
to remain in solution, while TPA crystallizes from the liquor. The inert
gas that was dissolved and entrained in the liquid under pressure is
released when the pressure is relieved and is subsequently vented to the
atmosphere along with the contained VOC (B). The slurry (11) fron the
crystallizers is sent to solid/liquid separators, where the TPA is recovered
as a wet cake (14). The mother liquor (12) from the solid/liquid separ -tnrj
is sent to the distillation section, while the vent gas (13) is discharged
to the rttnospheie (B).
Drying, Handling and Storage - The wet cake (14) from solid/liquid
separation is sent to dryers, where with the uee of ht=y usiaj n-propyl acetate as the water removing agent.
The aqueous phas« (28) contains faturatio^ amounts of jv-prupyl acetate and
methyl acetate, wh <.'h are stripped from the aqueous matter in the waatewater
still. Part of the bottoms product is used 13 process wat^r in absorption,
and the remainder (N) is sant to wastewafe treatment, A purge stream of:
the organic phase (30) goes to the methyl acetate still, where methyl
acetati; and saturation amounts cf water are recovered as rin overhead product
(31) and are disposed of as a fuel (M). rv-propyl acetate, obtained as the
bottoras product (32), is returned to the azeotrope still. Process losses of
jv-propyl acetate are made up from storage (33). A small amount of inert
ga.s, which is used for blanketing aud Instrument purging, is emitted to the
atmosphere through v^nt C.
C-TP\ Pur lf_icattun
The purifiestLon portion of the Mid-Century oxidation process involves
the hydrogenation of C-TPA over a palladium containing catalyst at ab'jut
232°C (450°F). High purity TPA is rec crystallised from a high pressure water
solution of the hydrogenated material.
The Olin-Mathieson manufacturing process is similar to the Mid-Cent-iry
process except the former uses 95 percent oxygen, rather than air, .is the
oxidizing agent. The final purification step consists essentially of a
5/C3 Chemical Process Industry 5.21-3
-------
continuous sublimation and condensation procedure. The C-TPA is combined
with small quantities of hydrogen and a solid catalyst, dispersed in steam.
and transported to a furnace. There the C-TPA is vaporized and certain of
the contained impurlti3s are catalytically destroyed. Catalyst and non-
volatile impurities are removed in a suries of filters, after which the pure
TPA is condensed and transported tc storage silos.
1-3
5.21.2 Emissions ard Controls
A general characterization of the atmo^pnerio emissions from the
production of C-TPA is difficult, because of tho variety of processes.
Emissions vary considerably, both qualitatively and quantitatively. The
Mid-Century oxidation process appears to be one of th£ lowest polluters, and
its predicted preeminence will suppress future emissions totals,
Tha reactor g.-is it vent A normally contains nitrogen (from air oxidation);
unreacti'd oxygen; unreacted j>—xylene; acetic acid (reaction solvent); carbon
monoxide, carbon dioxide, and methyl acetate from uxidatlor of £-xylene and
acetic acid not recovered by the high pressure absorber; and wau»r. The
quantity of VOC emitted ,u vent A can vary with absorber pressure and the
tempera cure of exiting vent >jasos. During crys lallir.a tion of tfrephthalic
acid aad separation of crystalized solids from the solvent (by centrifuge or
filters), noncondensible gases catrying VOC are released. These vented
£.tsfis and the C-TPA dryer vent gas are combined and released to the atmosphere
at vent B, Different methods usuJ in this process can affect the amounts of
noncondensible gases and ace impanying VOC emitted from tnis ven,..
Gases released from the distillation section at vi»nt C are the small
amount of gases dissolved in the feed stream to distillation; the inert gas
iia• d in inert blanketing, instrument purging pressure control; and the VuC
vapors carried by the noncondensable gases. The quantity of this discharge
is usually small.
The gas vented from the bag filters on the product storage tanks (silos)
(H) ia dry, reaction generated inert gas containing th« VOC not absorbed in
the high pressure absorber. The vented gas stream contains a small quantity
of TPA particulate that is not removed by the bag filters.
Performance of carbon adsorption control technology for a VOC ga.s
stream similar to the reaccor vent gas (A) and product transfer veit gas (D)
has b^en demonstrated, but, carbon monoxide (CO) emissions will not be
reduced. An alternaiive to the carbon adsorption system is a thermal oxidizsr
which provides reduction of both CO and VOC.
Emission -jources and factors for the C-TPA process are presented in
Table 5.21-1.
5.21-4 EMISSION FACTORS 5/63
-------
TABLE 5.21-1. UNCONTROLLED EMISSION FACTOR', FOR
CRUDE TEREPHTHALIC ACID MANUFACTURE8
EMISSION FACTOR RATING: C
Strean Emissions (g/k.g)
Designation .
Emission Source (Figure 5.21-1) Nonmethane VOC *C COC
Reactor v«:nt
Crystallization,
s paration, drying vent
Distillation and
recovery vent
Product transfer
vent
A
B
C
D
15
1.9
1.1
1.8
1?
-
-
?
'Factors are expressed as g of pollutant/kg of product produced,
, Dash - nut applicable.
Reference 1. VCC gas stream consists of methyl acetate, £-xylene,
and acetic acid. No methane was found,
Reference 1. Typically, thermal oxidation results in>992 ret'u-tion
of VOC and CO. Carbon adsorption gives a 977. reduction of VOC
.only (Reference 1).
Struam contains 0.7 g of TPA particulates/kg. VOC and CO emissions
originated in reactor ot'fgas (1C) used fur transfer.
References fur Section 5.21
I. S. W. Dylewski, Organic Chemical Manutacturing, Volurne 7; Selected
Processes, EPA-450/3-80-0.frfb, U. S. Environmental Protection Agency,
Research Triangle Park, NC, January 1981.
2. D. F. Durochet, el al., Screening Study To Determine Need for Standards
of Performance for New Sources of Dimethyl TerjBpht.halatu and Tereu_h_thal_ic
Acid Manufacturing, EPA Contract No. 68-02-1316, Radian Corporation,
Austin, TX, .July 197fc.
3. J. W. Pervier, ei. al., Survey Reports on Atmospheric Emissions from the
Petrochemical jndust-iy. Volume II, ? PA-/+50/3-73-C05b, U. S. Environmental
Protection Agency, Research Triangle Fark, NC. Apvll 1974.
'/8T Chetnical Process Indusn i 5 21-5
-------
5.22 LEAD ALKY!
5,22.1 Prcces'- Det^rl pttou 1
Two .Ukyl lead compounds, tetraethyl lead (TKL) and te^ramethyl lead
(.TM1-), are u-;ed as antiknock gasoline additives. Over 75 percent of the 1973
Mddltlve productio-i was TEL, r.ore than 90 percent of which was made by alkyl-
of sodium/le.jd alloy.
Lead alky! Is producjjd in autoclaves by the re->ct ton of s jr. IUT. 'lead
alloy wiLh an oxcdss of eith-.r ethyl (far TEL) or methyl ('.or 1ML) chloride In
the presence if .-ice font: ratal\st. The reaction macs Is distilled to separate
the product, whlc'i Is then purified, filtered and mixed with chloride/broraide.
iddicives. Residue is sluiced to a sludge pit, froia which the bottoms are
sent to TO indirect steam dryer, and the dried sludge is fed to a reverberatovy
furnace to recover lead.
Gasoline additives are also manufactured by the electrolytic process, in
which a solution of ethyl (or methyl) magnesium chloride and ethyl (or methyl)
Chloride is elect rolyzod, with le.id metal as the an-->de.
5.22 Emissions and Controls
1
Lead emlfjslons from the sodium/lead alloy process consist of par'. Iculate
lead oxldfc frjin the r-'covery furnace (and, to a lesser extent, i"rom the melting
fjrnace and alloy reactor), a!kyl lead vapor from process ven'js, and fugitive
i-n is ^ions fron the sludge pit.
Emlsslors friv?. tin lead recovery furnace are controlled by fabric filters
jr J
-------
TABLE 5.22-1. LEAD ALKYL MANUFACTURE LEAD EMISSION FACTORS*
EMISSION FACTOR RATING: B
Process
r;leotrolytlcb
Sodium/lead alloy
Recovery furnace0
Process vents, TELd
Process v. -,ts, TMLd
Sludge plc.9^
kg/Mg
0.5
28
2
7?
C.6
Lead
Ib/ton
1.0
55
4
150
1.2
aNo information on other emissions from lead al'
-------
5.23 PHARMACEUTICALS PRODI.'CTION
5.23.1 Process Description
Thousands oi individual products are categorized as pharmaceuticals.
These products usually are produced in modest quantities in relatively
small plantf using batch processes. A typical pharmaceutical plant will
use the samt equipment to make several different products at different
times. Rarfly is equipment dedicated to tae manufacture of a single
product.
Organic chemicals are used as raw materials and as solvents, a~>d
some chemirjls such as eth.'inol, acetone, isopropanol and acetic anhyd
ride are used in both ways. Solvents are almost always recovered and
used many tires.
In a typical batch process, solid reactantri and sjlvent are charged
to a reactor where they sre held (and usually heated) until the Jt-siref1
product is formed. The solvent is distilled off, and the crude residue
may be treated several times with additional solvents to purity it. The
purified material is separated from the remaining solvent by centrifuge
and finally is dried to remove the last traces of solvent. As a rule,
solvent recovery is practiced for each step in the process where it is
convenient and cost effective to do so. Sone operations involve very
small solvent losses, and the vapors are vented to the atmosphere through
a fume hood. Generally, all operations aru carried out inside builu-i-.igs,
so some vapors may be exhausted through the building ventilation system.
Certain pharmai autical.T - especially antibiotics - are produced by
fermentation processes. In the=e instances, the reactor contains an
aqueous nutrient mixture -.;ith living organisms such as fungi or bacteria.
The crude antibiotic is recovered by solvent extraction and is purified
by essentially the same methods described above for chemically synthe-
sized Pharmaceuticals. Similarly, other pharmaceutical?; are produced by
extraction fron natural plant or animal sources, The production of
insulin from hog or beef pancreas is ar example. The processes are not
greatly different from those used to isolate antibiotics from fermen-
tat ion broths.
5.23.2. Emissions and Controls
Emissions consist almost entirely of organic, solvents that escape
from dryers, ^eactors, distillation .systems, storage tanks and other
operations. These emissions are exclusively nonmethane organic compounds.
Emissions of other po'lutants are negligible (except for particulates in
unusual circumstances) and are rot treated here. It is not practical to
attempt to evaluate emissions crom individual steps in the production
process or to associate emissions with individual pieces of equipment,
because of the great variety of batch operations that may he r^r-^ied out
JO/80 Chemical Process Industry 5.23-1
-------
at a single production plant. It is more reasonable tr, obtain data on
total solvent purchases hy a plant anJ to assume that these represent
replacements for solvents lost by evaporation. Estimates can be refined
by siibtractii.g the materials that do not enttr tbe air because of being
incinerated or incorporated into the pharraacfuticnl product by chemical
reaction.
If plant-specific infcrraation is not available, industrywide data
may be used instead. Table 5.23-1 lists annual purchases of solvents by
U.S. pharmaceutical manufacturers and shows the ultiui£"-e disposition of
each solvent. Disposal ,r,:thons vary so widely with the type of solvent
that it is not possible LO re-oramend average factors for air emissions
from generalized solvents. Specific information for individual solvents
must be used. Emissions can he estimated by obtaining plant-specific
data on purchases of individual ^o'/ents and competing the quantity of
each solvent that evaporates into the air, either from information in
Table 5.23--1 or from information obtained for the specific plant under
consideration. If to Wept volumes are given, rather than weights,
liquid densities in Table 5.23-1 can be used to corrpute weights.
Table 5.23-1 gives for each plant the percentage of each solvent
that is evaporated iuto the air and the percentage that is flushed into
the sewer. Ultimately, much of the volatile material from the sewer
will evaporate and will reach the air somewhere other than the pharma-
ceutical plant. Thus, for certain applications it may be appropriate to
include both the air emissions and the sewer disposal, in an emissions
inventory that covers a broad geographic area.
Since solvents are expensive and must be recovered and reused for
economic reasons, solvent emissions are controlled as part o: the normal
operating procedures in a pharmaceutical industry. In addition, most
manufacturing is carried out insJde buildings, ,;herr solvent losses must
be minimized to protect the benlrh of the workers. Water o" brire
cooled condensers are the most common control devices, with carbon
adsorbers in occasional use. With each of these methods, solvent can be
recovered. Where the main objective is noc solvent: reuse bu;: is the
control of an odorous or toxic vapor, scrubbers ov incinerators are
used. These control systems are usually designed to remove a specific
chemical vnpor and will be used only wh^n a batch of the corresponding
drug is bein^ produced. Usually, solvents are not recovered from
scrubhii-s and reused, arid of course, HO sol.va'it recovery is possible
from an incinerator.
IL is difficult to make a quantitative estimate of the efficiency
of each control method, because it depends on the process being con-
trolled, and pharmaceutical manufacture involves hundreds of different
processes. Incinerators, carbon adsorbers and scrubbers have been
reported to remove- greater than 90 percent of the organics in the
control equipment Inlet stream. Condensers ^re limited, in thai they
can only reduce the concentration in the pas scream to saturation at the
5.23-2 EMISSION FACTORS 10/80
-------
condenser temperature, but not kelov that level. Lowering the temper-
ature will, of course, lower the concentration at saturation, but It is
not possible to operate at a temperature below the freezing point of one
of r.ie components of the £as strean.
TABLE 5.23-1.
SOLVENT PURCHASES AND ULTIMATE DISPOSITION BY
PHARMACEUTICAL MANUFACTURERS3
Solvent
Acttlc AcIO
ACfllC AnlVOrtM
Actlont
*£«tor,1tr1lt
tmy\ AcitiM
tayl AUoho,
Mnjint
ItlMtn (W.O)
BuUnel
Urfaon 1ttr«(|-,lorld«
Cnlorofom
Cycloh* »yli>iite
n-Dichloroteiuenc
D'ethylartnne
(Hethyl Ctrtorkiie
DlB«thy1 Aciliitide
DtMlhyl Fomaitde
01»»thyHuHo»t.1e
1.4-D1o*inf
ttlinol
Lt»y) Acttiti
Ethyl Brwiide
CtDjltnt Glycol
UHyl Cther
Fortaldenyde
Forawldt
Frtons
He ten*
llOfiutyrjldehjrde
Isopropinol
Iioprop/l Ar n«te
Iloprgpyl Ether
Mtiningl
Mtlhyl Cfllutoi.e
felhylinf Chloride
Nethy' £ttiyi Hil»i»«
Nrtfcyi For*«t(.
Hetiyl liobutvi wtone
Polyethylene Glycol 600
Pyrldln*
Skilly Sclieni e (htxtnci)
Tetrt>>ydrof jrir.
Toluer.f
lrunij"-iif-tlunu
lylene
Ariiual
Kiruliisc
(nclric tonj;
130
1.266
12,040
?S
2bS
1,410
',-10
uo
S20
t.aio
MO
3. 950
60
5n
w
9!
1.^20
750
4}
13,730
2/IBO
4S
60
2 SO
30
443
?,I50
430
p-
? «0
4&0
2i
'.550
its
10,000
26.
4)5
?6r,
j
J
1 ,4iD
4
6,010
13i
3.09C
Ultiaict DiiposUlon (pxrcfit;
Air
tamtons
1
1
14
B3
42
VI
29
24
11
57
2
94
4
7
71
1
S
10
30
.
.
B5
'9
»
0 1
17
SO
14
23
SO
31
47
53
66
.
BO
.
29
.
31
IDC
&
Seotr
a;
57
22
17
SB
37
S
•»
S
tt
€
71
.
3
28
6
47
100
100
4
77
C7
.
_
&0
17
11
5,0
45
S3
5
12
74
.
100
2
.
14
.
19
Incineration
.
U
.
_
U
1
8?
„
_
_
:r
71
7
20
»
_
_
.
.
U
17
(1
14
B
V>
23
.
.
.
«9
100
26
70
Solid Wistt ur
Ci.nirict Mul
.
7
_
m
8
56
38
.
.
_
93
6
95
1
]
.
11
26
68
7
,
6
n
1 1
.
.
.
.
.
29
S
Product
17
42
19
_
1
10
100
11
_
100
.
25
_
6
4
7
99.9
»
4b
,
4
,
_
U
20
100
Liquid Oer.stiy
)b/Q«l I (A't
By
• *
9.0
6.6
it
, V
7.3
6.8
7 i
f • j
NA
6.8
13.3
12. S
J 2
10 9
59
B.I
7.9
V9
11.1
66
^
.i
1 .1
.3
.0
,5
.&
6
.e
.3
.0
-------
Peference for Section 5.23
1. Control ui Volatile Organic Emissions fror: Manufacture of
Synthesized Pharmaceutical Products. EPA-450/2-78-029, U. S.
Environmental Protection Agency, Research Triangle Park, NC,
December 1978.
5.7.3-4 EMISSION FACTORS 10/80
-------
5.24 MALEIC ANHYDKIDE
5.24.1 General
The dominant end use of tnaleic anhydride (HA) is in the jroduc"ion of
unsaturated polyester resins. These laminating resins, which have high
structural strength and good .'iielectric properties, have a variety of
applications in autonobile bodies, building panels, molded boats, chemical
storage tanks, lightweight pipe, machinery housings, fum'.turd ;and heated before entering the
tubular reactor. Inside the reactor, the benzene/air mixture i« reacted in
the presence oe a catalyst which contains approximately 70 percent vanadium
pento>;idfi (V 0 ), with usually 25 to 30 percent molybdenum trioxlde (MoO^),
forrtffng a vapor of MA, water and carbon dioxide. The vapor, which may also
contain oxygen, nitrogen, carbon monoxide, benzene, r.aleic acid,
formaldehyde, fcrmic acid and othnr compounds from side reactions,
tho reactor .ind is cooled and partially condensed so that ,ibout 40
of the MA is recovered in a crude liquid state. The --ffluent, is then paused
through a separator which directs the liquid tc: stored and t.ue remaining
vapor to the product recovei/ absorber. The absorber ooniacts the vapor
with water, producing a liquid of ahou: 40 percent maleLc acid, "ha
5/83 Chejiical Process Industry 5.24-1
-------
n
H
70
AIR
QKD
COMPRESSOR
. uumr
K_j£
d b *
BENZENE
STORAGE _
VAPORIZER
STEAM
STEAM
INTERCHANGE^/'
I
WATER
WAItH
®
CONDENSER,
T^CTORIS, (j^fTP RECOVERY
*t
SPENT CATALYST
DEHYDRATION
LULUMN
XVt.tKt
T
MAKE. UP
WATER
ABSORBER
I
XYLENE
STORAGE
T
I"
VACUUM
SYSTEM
XYLENE
STRIPPER
WATER
OUT
UN
f^
J ARF
FRACT10NATIO
COLUMN
|
-------
40 percent mixture Is converted to MA, usually by azeotropic distillation
with xylene. Sore processes may use a double effect vacuum evaporator at
this point. The effluent then flows to t'ie xylene stripping column where
the xylene is extracted. This MA Is then combined in storage with that from
the separator. The molten product is aged to allcw color forming impurities
to polymerize. These are then removed in a fracticnation column, leaving
the finished product. Figure 5.24-1 represents a typical process.
MA product is usually stored in liquid form, although i T sometimes
flaked and palletized into briquets and bagged.
2
5.24.3 Lmisaiops ar.d Controls
Nearly all emissions from MA production are froin the main process vert
of the product recovery absorber, the largest ve.nt in the process. The
predominant pollutant is unreacted benzene, ranging from 3 to 10 percent of
the total benzene feed. The refining vacuum rystem vent, the only other
exit for proce :j: emissions, produces 0.28 kilograms (0.62 Ib) per hour of MA
and xylene.
Fugitive emissions of benzene., xylene, MA and maleic acid also arise
from the storage (see Section '.3) and handling (see Section 9.1.3) cf
benzene, v/lenc and M\. Dust from the briquetting operations can contain
MA, but no data are available on the quantity of nucn emissions.
TABLti 5.24-1.
COMPOSITION OF UNCONTROLLED EMISSIONS FROM PRODUCT
RECOVERY ABSORBER3
Component
Nitrogen
Oxygen
Water
Carbon dio
-------
organics, with a molecular weight greater than 116, and they produce
a small percentage of total emissions.
Benzene oxidation process amisslo >s can be controlled at the main vent
by means of carbon adsorption, thermal incineration or catalytic incineration.
Benzene emissions can be eliminated by conversion to the n-butane process.
Catalytic Incineration ana conversion from the benzene process to the n-butane
process are not discussed for lack of data. The vent from the refining
vacuum system is combined with that of the main process, as a control for
refining vacuum system emissions. A carbon adsorption sy.stem or an incine-
ration sys'L-ii can be designed and operated at a 99.5 percent removal
efficiency for benzene and volatile organic compounds with the operating
parameters given in Appendix D of Reference 2,
TAB'E 5.^4-2. EMISSION FACTORS FOK. MALE1C ANHYDRIDE PRODUCTION3
RMISSIO-. FACTOR RATING: C
Nonmrithane VOC Benzene
Source kg/Mg Ib/ton kg/Mg Ib/ton
Product vents
(recovery absorber and
refining vacuum system
combined vent)
Uncontrolled 87 1/4 67.0 134.G
With carbon adsorption0 0.34 0.68 0.34 0.68
With incineration 0.43 O.ye 0.34 0.68
Storage and handling.
emissions - -
Fugitive emissions'" - -
Secondary emissionsf N/A N/A N/A N/A
^
Mo data are ,»vailable for catalytic incineration or for plants producing MA
froni n-butane. Dash: see footnote. N/A: not available.
VOC also includes the benzene. For recovery absorber and refining vacuam,
VOC can be MA and xylene; for storage and handling, HA, xylene ind dust
fro.ii briquet ting ope'.* tions; for secondary emissions, residual organics
fron spent catalyst, excess water from dehydration column, vacuum system
water, and fractional ion column reyidu.es. VOC contains no methane.
Before <.>.xhau?t gas stream goes in'^o carbon adsorber, It Is scrubbed with
caustic to remove organic acids and wati;r soluble organics. Benzene is the
only likely VOC remaining.
See Section 4.3.
cSce Section 9.1.3.
Sect ndary emission sources are excess water fr'>m dehydration column, vacuum
system water, and organics from fractionation column. No data are available
on the quantity of thesi eml >riion.s.
5.24-4 EMISSION FACTORS 5/83
-------
Fugitive emissions from pumps and val\iaa may be controlled by an
appropriate leak detection system and maintenance program. No control
devices are presently being used for secondary emissions.
References for Section 5.24
It B. Dmuchovsky and J. E. Franz, "Maletc Anhydride", Klrk-Othmqi:
Encyclopedia of Chemical Technology, Volume 12, John Wiley and
Sons, Inc., New York, NY, 1967, pp, 819-837.
2, J. F. Lawson, Emission Control Options for the Synthetic Organic
Chemicals Manufacturing Industry! MaleLc Anhydride Product Report,
EPA Contract No. 66-02-2577, Hyclrosclence, Inc., Knoxville, TN,
March 1978.
5/b3 Chemical Process Industry 3.24-5
-------
6. FOOD AND AGRICULTURAL INDUSTRY
Before food -rid agricultural products are jsed by the consumer ihey undergo n number of ^locessing steps.
sv.'h as refinement, preservation, und piiMluct improvement, as well us storage and handling, packaging, and
shipping This section deals v.'th the processing of food and agricultural products and the intermediate steps that
present air pollu'ion problems, tmissior. (actors are presented tor industries where data wi>e available. The
primary puiiuui,: sr'ii'ed frum these processes is particulate matter.
6.1 ALFALFA DEHYDRATING
6.1.1 General"
Dehydrated alfaJfa is a meal product resulting from the rapid drying of alfalfa by artifical means at
temperatures above 212°F (100°C). Alfalfa meal i« used in chicken rations, cattle feed, hog rations, iheep feed,
turkey rrash, and other formula feeds. It is important for if. protein content, growth and reproductive factors,
pigmenting xanthophylls, and vitamin contributions.
A schematic of a generalized alfalfa dehydrator plant is given in Hgure 611 Standing alfalfa is mowed and
choppf.1 in the field and transported by truck to a dehydrating plant, which is usually located within 10 miles of
the field. The truck dumps the chopped alfalfa (wer chops) onto a self-feeder, which carries it into a direct-fired,
rotary drum. Within the drum, the wet chops are dried from an initial moisture content of about 60 to 80 percent
(by weight) to about S to 16 percent. Typical combustion gas temperatures within the oil- 01 gas-fired drums
range from 1800 to 2000°F (980 to !092°C) at the inlet lo 250 to 300°F (120 to 150"C) at the outlet.
Frum the drying drum, the dry chops are pneumaticall: conveyed into a primary cyclc-.e that separates them
from the high-moisture, high-temperature exhaust stream. From the primary cyclone, the chops are fed into a
hammermilL which grinds the dry chops into a meal. The Tisal is pneumatically conveyed from the hammermiil
into a meal collector cyclone in which the meal is separated from the airstream and discharged into a holding bin.
Meal is then fed into a pellet mill where it r. steam conditioned and extruded into pellets.
Ffom the pellet mill, the pellets are either pneu.natically or mechanically co.iveyed ic a cooler, through which
air is drawn to cool the pellMs and, in some cases, remove fines. Fines removal is more commonly effected in
shaker screens following or ahead of the cooler, with the fines being conveyed back into the meal colleLtur
cyclone, meal bin, or pellet mill. Cyclone separators may be employed to separate entrained fines in the crH*r
exhaust and to collect pellets when the pellets are pr.ci"natically cr-inyed from the pellet mill to the coo'er.
Following cooling and screening, the pellets are transferred to bulk stLrage. Dcnydrated alfalfa is most often
stored and shipped in pellet frrm; however, in some instances, the pellets may he ground in a hammermiil and
shipped in meal form. When the finished pellets or giound pellets arc pneumatically transferred to storage or
loadout, additional cyclones may be employed for product airstream separation at these locations.
6.1.2 Emissions and Controls '"3
Paniculate matter is the primary pollutant of coi.jern from alfalfa dehydrating plants although some odors
arise from the organic volatiles driven off dui.ng drying. Although the major source is the primary cooling
cyclone, lesser suiaces incljds the downstream cyclone separators and the bagging and loading operations.
4/76 6.1-i
-------
Emission factors ror (he various cyclone separators utilized in alfalfa dehydrating plants are given in Table
6.1-1. Note thai, although these iources are comincn to many plants, there will be considerable variation from
the geneialized flow diagia.n in Figure 6.1-1 depending on the desired nature of the product, the physical layout
of the plant, and the modifications made fui air pollution control. Common "auctions include ducting the
exhausi gas stream from one or more of the downstream cyclones hack (Sou^h (he primary cyclone and ducting
a portion of the primary cyclone exhaust back into (he furnace. Anothei modification involves ducting a part of
the meaJ collector cyclone exhaust back into the haniinormill, with the remainder ducted to the primary cyclnne
or discharged directly to the atmosphere. Also, additional cyclones n-jy be employed if the pellets are
pneumatically rather than mechanically conveyed from the pellet mill to the cooler or if the finished pellets 01
ground pellets aic pneumatically conveyed to storage or loadout.
Table 6.1-1. PARTICULATE EMISSION FACTORS FOR ALFALFA DEHYDRATING PLANTS
EMISSION FACTOR RATING: PRIMARY CYCLONES: A
ALL OTHER SOURCES: C
Sources3
Primary cyclone
Meal collector cyclone^
Pellet collector cyclone6
Pellet cooler cyclone*
Pellet regrind cyclone^
Storage bin cyclone11
Emissions
Ib/ion of product*5
10 c
2.6
Not available
3
8
Neg.
kg/MT of product1-
6 =
1.3
Not available
1.5
4
Neg.
*The cyclones used for product/eirftream separation are thu air pollution sources in alfalfa dehydrating plants.
All far tort at e bastnJ on References 1 and 2.
"Prctdret consists ul meal or pellets. Thess factors can b« applied to the quantity of incoming wet chop* by
dividing by * facior of four.
cThi* average factor may be used even when other cyclone exhaust streams art ducted back into fia primary
cyclone, Em itioni fro-fi primirv cyclonai may range frori 3 10 35 Ib/ton (1.5 to 17.5 kg/MT) of product
and are morn a function of the operating procedure* and process modification* made for air pollution control
than whether othar cyclone exhausts Jra ducted back through the primary cyclone. Uie 3 to 15 Ib/ton {1.5 10
7.6 kg/MT) or plants employing good operating procedues and process modifications for air pollution control.
Use higher valu«s for older, unmodified, or leal well run plants.
'T'his cyclone is alto called the air meal separa'or or haminemnill cyclone. W..en the meal collector exhaust is
ducted back lo the primary cyclone and/or the harrtmemnill, this cyclone ii no longer a source.
°Thiscyclone will only be present if the pellets ara pneumatically transferred from ttiapeilel mill to the pellet
cooler,
*This cyclone is tlso called the pellet meal air separator or pellet mill cyclone. When the pellet cooler cyclone
exhausi i-, ducted back into the primary cyclone, it is no longer a soiree
9jhn cyclone is also called the pellet regrind air leoarator. Regrind operations are more commonly found at
terminal rorage facilities than at dehydrating plants.
Small cyclone collectors may be used to collect the finished pellets when they are pneumatically transfened
lo storage
Air pollution control (anc1 product recovery) i; accomplished in alfalfj dehydrating plants in a variety of ways.
A simple, yet effective technique is the proper maintenance and operation of ihe alfalf* dehydrating equipment.
Particulate emissions can bt reduced significantly if the feeder discharge rates are uniform, if thr drye; furnace is
operated properly, if proper airflows ar^ employed in ti:e cyclone collectors, and if me hamrnermill is well
maintained and nul o\erloaded. It :s especially importani in thi. regard not to overdry nnd possibly burn the
chops as this results in the generation of smoke jnd increased fines in the grinding anr> pellctizing operations.
6.1-2
EMISSION FACTORS
4/76
-------
•n
i
as
I
o
Q,
FRESHXUT
ALFALFA (WET CHOPS)
FROM F!Ci.O
TRUCK DUMP
AMD LIFT
PELLET
COOLER
CYCLONE
SECONDARY
I MEAL
COILECTQ
PRIMARY
PELLET
QLLtCTOB
:\
NATURAL
GAS
BURNERS
'TORAGE
LOADOtiT
Figure 6.1-1. Generalized flow dia^-am I'OT alfalfa dehydration plant.
-------
Equipment modification provides another means of participate control. Existing cyclones can i/c replaced with
more efficient cyclones and concomitant air How systems. In addition, the furnace and burncr:> can be modified
or replaced to minimize flame impingement on the incoming gieen 'hops. In plants where the hammermill is a
production bottleneck, a tendency exists to overdry the chops to increase throughput, which results in increased
emissions. Adequate harninermiU capacity can reduce this practice.
Secondary control devices can be emplo>ed on the cyclone solicitor exhaust si reruns. Generally, this practice
his been limited to the installation of secondary cyclones or fabric fillers on the meal collector, pellet collector,
or pellet cooler cyclones. Some measure of secondary control can also be effected on these cyclones by ducting
their exhaust streams back into the primary cyclone. Primary cyclones are not controlled by fabric filte.-s because
of tht hi^ moisture content in the resulting e\!iaust stream. Mtdium energy vet scrubbers a
-------
6.2 COFFEE ROASTING
6.2.1 Process Description'-
Coffci.1, which is imported ir the form uf green beans, must be cleaned, "ilni.led, roasied. and packaged befui.>
being sold. In a typical coffee toasting opetntion, Ine green coffee beans are freed of dust and chaff by dropping
the beniis into a current of air. The cleaned b';ans are then sent tc a hate'? nr continuous roaster. During the
ruastina, moisture is driven off, th? beans swell, and chemical changes lake place that give t) e roasted beans their
•ypical color and jronia. Wher. U~c beans have icached a certain color, they avc quenched, cooled, and stencil
6.2.2 Emissions1-3
Dusl, chalt, coffee bean oils (as misls), smoke, an ! odors aic the principal air contaminants emitted from
coffee processing. The major source- of particulale emissions ancl pMC'ically the only source of lidehydes,
nitrogen oxides, and organic acids is the roasting process. In a direcl-f red Boaster, gases are vented without
recirculation througli the flame In the indirect-tired rousur, however, a portion of the roaster gases are
rccirculated and particulate emifiions an- reduced Emissions ol both s;--,3ke and odors fiom the roasters can be
almost completely removed by :i properly designer afterburner.' •'
Particulale emissions also occur from the strner and cooler. In the stonir, contami'ialinp materials heavier
than the ruastcd beans an; separnied I'rom the b>.-ans by Jn air stream 'n the cco!ei. quonchiiig the hot roasted
beans with wuer causes emissions of large quantities of stea.n and som? particulate matter 3 Table 6.2-1
summari/es ctnissions rrom the various operations involved in ci.lice processing.
6.2-1. EMISSION FACTORS FOR ROASTING PFIOCESSES WITHOUT CONTROLS
EMISSION FACTOR RATING: B
l:>ollutant
Type of process
Roaster
t)ircct-fired
Indirect fired
Storer and r.coUi^-
Insiant coffee spray dryer
Particulars*
Ib/ton
7 r
4.2
1.4
1.4d
kg/MT
3.8
2 1
0.7
0.7d
N0xb
Ibvton
0.1
01
kg/MT
fi.05
0.05
Aldehydes"
Ib/ton ] kg/VT
0.2
0.2
C.I
0.1
Orgunic ac;dsb
Ib/ton
0.9
09
kg/MT
0.45
0.45
'Deference 3.
bRpterence 1.
clf cyclone is Md, erniG&ions can be ieduced t»v 70 percent.
dOyclcne olu: \xi scrubber always used, rspreseTting a conirolied factor
2/72
Food and Agricultural InduMry
6.2-1
-------
References for Section 6,2
1, Polglase, W.L.. H.F Dcy, and R "I Walsh, folio* Processing. In: <\ir Pollution Engineering Manual.
Danielson. J.A, (ed.|. U.S. t)HEW, PHS, Naiional Cenicr for Air Pollution Control, ("mcmnali, Ohio.
Publicatio. Number'W9-AP-40. I %7. p. 746-740.
2. Duprey, R.L. CoinpiUiion ,>('Air I'ollutunt Eiimsiun Fjc'»r. l.'.S. DUliW, PUS, Saiional Center for Air
Pollution Control. Durham. K.C. PHS Puhlicacon Number -W-AP-42 Il>6K. p. \<)-2Q.
3, Paitee, F- Air Pollniion in (he Cufiee RoaiUng Industry. Revised t.d. U.S. DHEW. PUS. Division of Air
Pollution. Cincinnati, Ohiu. fublica-ior Number WJ-AP-9. 1966.
6.2-2 EMISSION FACTORS 2/72
-------
6..J COTTON GINNING
6.3.1 General1
The primary function of a cotton gin i* to separate seed from the lint of raw seed cotton. Approximately one
500-pound l»ale of cotton can be produced from 1 tori of seed cotton. During ginning, lint dual, fine leaves, and
other trash are emitted into the air. The degree of pollution depends on the seed cotton trash content, which
depends on the method used to harvest the cotton. Handpickcd cotton has a lower trash content than machine-
stripped cotton.
6.3.2 Process Description2
Figure 6,3-1 is a fiow diagram of the typical coiton ginning process. Each of the five ginning step* and
associated equipment ii described in the fallowing sections.
6.3,2.1 Unloading Syiiem — Trucks and trailers transport seed cotton from the field to the gin. Pneumatic
systems convey the seed cut tun from the vehicles or storage houses to a separator and feeH control unit. (Some
gins utilize a stone and green boll trap for preliminary tiash rernovHl) The screen assembly in the separator
collects the seed cotton and allows it to fall into the feed control unit The conveying air flows from ihc separator
to a cyclone system where it is cleaned and discharged to the atmosphere.
6.3.2.2 Seed Cot Ion Cleaning System — Seed cotton is subjected to three basic conditioning processes — drying,
cleaning, and extracting — before it enters the gin stand for separation of lint from seed. To ensure adequate
conditioning, cotton gins typically use two conditioning systems in series (see Figure 6.3-1).
Cotton dryers are designed to reduce the moisture content of the seed cotton to an optimum level of 6.5 to 8.0
percent A push-pull high-pressure fan system conveys seed cot ion through the tower dryer to the cleaner, which
loosens the cotton and removes fine particles of foreign matter such a" leaf trash, sand, find .lirt. Large pieces of
foreign matter (e.g.. sticks, stems, and burrs) are removed from the s°>ed cotton by a different process, referred to
as "extracting " Several types of extractors are used at cotton gins: burr machines, stick machines, stick and burr
machines, stick and greon leaf extractors, and extractor-feeders. The burr machine removes burrs and
pneumatically conveys them to ihe trash storafP area. The seed cotton then enters » stick (ora stick and green
leaf) machine, which removes sticks, leaves, and stems. Afterwards, the seed cotton is pneumatically conveyed to
the ne .1 processing step
6.3.2.3 Overflow System — From the final conditioning unit, the seed cotton enters a screw conveyor distributor,
which apportions trip seed cotton to the extractor-feeders at a controlled rate. When the flow of seed cotton
exceeds the limit of the fxtracior-feeders, the excess seed cotton flows into the overflow hopper. A pneumatic
system transfers seed cotton fi om the overflow hupper back to the extractor-feeder as required.
6.3.2.4 Lint Cotton Handling System — Cotton enters the gin stand through a. "huller front," which performs
some cleaning. A saw grasps the locks of cotton and draws them through a widely spaced set of "huller ribs,"
which strip off hulls and sticks. The cotton iocks are then drawn into iheroll box, where seeds are separated from
the fibers. As the seeds «rr removed, lh<:y slide down the face of the ginning ribs and f*ll to the bottom of the gin
stand for subsequent removal to stcra^e. Cotton lint is removed from the saw by • brush or « blast of air and
conveyed pneumatically to (he lint cleaning system for final cleaning and combing. The lint cotton is separated
from the conveying air stream h • a separator that forms the lint into a batt Thisbatt is fed into the first set of lint
cleaners, where saws cumb ihe lint cotron and remove leaf particles, grass, and moles.
12/77 Food and Agricultural Industry 6.3-1
-------
W
c
n
5
KS
UNLOADING SYSTEM
COTTON
I STORAGE
uniKF
A. S
STONE
GREEN
aci.:
UNLOADING
SEPARATOR
I
"ir
SEED COTTOM CLEANINB SYSTEM
i iX \IRAP
1 WAGON Jr ^s^ 1
ATTERV CONDENSER 1 1
!l
t i
Ft:
CONT
UN
S
ED
ROL
T
-------
6.3.2.5 Battery Condenser and Baling System — ! int cotton is pneumatically transported from (lit- lint cleaning
sy.ite.rn to a battery condenser, which consist,, of nrums equipped wilh screens tha( separate he lint cotton from
:he con\ eying air. Tb-? conveying air is then discharged through an in-line filter or cyrl* nef before being
pxhaus'ed to the atmosphere The ba. ol lint cotton is then fed into the bairns press, which parks it m(n uniform
bale* of i-
«>.H.3 Emission and Controls
The niHJnr sources of particulutes from cotton pinning c»n be arranged inlo 10 emission so met*
t -ategurie.s hust-d on spec- fie ginning operations (Figure 6.3-2). Three primary me thuds of purlieu Inc.
ituilroi are in ust: (1) high efficiency cyclones oil the hiah-pressure fan Hischdrges with < ollt'clioi.
ffticieni-ics pr-"i.trr than 99 percent,- (2) in-iinc fillers on Ion-pressure fan exhaust vents with
efficiencies of approximately 80 percent, and (3; fine screen co>eringson condenser drums in I he low-
pressure systems with effifii-nc'ies of ••pproximatcly "0 percenl.1"' The unifiltei i* a new concept ror
i (illccting all wastes froii.' cotton «ins. it is designed lo replaeu all cyclones, in-line fillers, and covered
condenser drums, and has a Milleelion efficiency of up to 99 percent.1
Table 6.3-1 presents emission factor? from ui controlled cotton ginning operations.1
Tnhle 6.3-2 presents emission factor* for u typieal cotton gin equipped with a-.uiluble control
devi'. u>; the ilutu base imulvcil tottori gins with ii lariely of different control devices, incl'Hiug
cyclones, in-line fillers, screen coveriiij.'*, and nriifillers.*.*-''Tht total emission factor can hee*pected
to vary hy roughly a factor of two, dc-pcndinp cin the l» ^ie of weed cotton, the trash content of the seed
cotton, the maintenance uf control dc\ices. and the plant operation procedures.
12/77 Four! and Agricultural Industry 6,3-3
-------
UNLOADING
SYSTEM
14* EMISSIONS'
(8) EMISSIONS
SEED COTTON
CLEANING
SYSTEM
N0.1 DRYERAND
CLEANER
4-
LINT COTTON
HANDLING
SYSTEM
EXTRACTOR
NO. 2 DRVERAND
CLEANER
EXTRACTOrt/FEEDER
GIN STAND
* - -I MOTE FAN
NO. I LINT
CLEANER
NO. 2 LINT
CLEANER
I
BATTERY CONDENSER
AND
I BALING PRESS
OVERFLOW
DISTRIBUTOR
SEPARATOR
*• EMISSIONS (11
REMISSIONS (2)
• EMISSIONS (3)
•EMISSIONS (5)
•EMISSIONS (6)
*- EMISSIONS (7)
REMISSIONS (9)
(1 (EMISSIONS *•
MASTER
TRASH
FAN
TRASH STORAGE
6.3-4
Figure 6.3-2. Emissions from a typical ginning operation.
EMISSION FACTORS '2/77
-------
T»W« 3.3-1. EMISSION FACTORS FOR COTTON GINNING
OPERATIONS WITHOUT CONTROL"-
EMISSION FACTOR RATING: C
Process
Un'oading fan
Seed cotton
cleaning system
Cleaners
and dryers'4
Stick and burr
machine
Miscellaneous8
Total
Estimated total
paniculate
Ib/bale
5
1
3
3
12
kg/bale
2.27
0.'5
1.36
1.36
544
Participates
> 100 pim
settled out, %c
0
70
95
50
—
Estimuted emission
factor (released
to atmosphere)
Ib/bale
5.0
0.3
0.2
1.5
7.0
kg/bale
2.27
0.14
0.09
0.66
3.2
'Reference 1.
bOne ball *«ighs 500 pounds (226 kilograms).
'Percentage of the particles that settle out n the plant
^Corresponds 10 items 1 and 2 in Table 6.3-2
eCorresponus to items 4 through 9 In Table 6.3-2
Table 6.3-2. PARTICULATE EMISSION FACTORS
FOR COTTON GINS WITH CONTROLS*
EMISSION FACTOR RATING: C
Emission sourceb
1. Unloading fan
2. No. 1 dryer and dinner
3. No. 2 dryer and cleantr
4. Trash fan
5. Overflow fan
6. No. 1 lint cleaner condenser
7. No. 2 lint cleaner condenser
8. Mote fan
9. Battery condenser
10. Master trash fan
Total
Emission factor
lb/balec
0.32
0.18
0.10
0.04
0.08
0.81
0.15
0.20
0.19
0.17
2.24
9/kg
0.64
0.36
0.20
0.08
0.16
1.62
0.30
0.40
038
0.34
4.48
'Reterencos 2.6-9.
bNumbers correspond to those in Figure 5.3-2
CA bale o( cotton weighs 500 pounds (227 Kilograms)
12/77
Food and Agricultural I::duftlr>
6.3-5
-------
References for Section 6.3
1. Air-borne Partuulate Emissions from Cotton Ginning Operations. L.S. Department of Health,
Education and Welfare, Public Health Service, Tuft Sanicary Engineering Center. Cincinnati,
Oh. I960.
2. Source Assessment Document !\o. 27, Ccllon Gins. Monsanlo rU-search Corporation. Davton. Oh.
Prcpttred for t'.S. Environmental Protection Agency, Research Triangle Park, N.C. Publication
No. EPA-600 2-78-(HMa. Dei-emlirr N7.Y
3 NiiCaskill. O.I.. und K.A. VI csley. The- Lat-sl in Pollutiun Control. Texas Cotton G'mners' Join nul
and Yearbook.1974.
4. Baker, Ro). F. and Calvin B. Parnell, Jr. Tliree Types of (Condenser Filters for Fly Lint and Dust
Control at Cotton (»i.:s. I .S. DepHrtment of Agriculture. Agriculture Research Ser\ ice. Bell*\ ille,
Md. ARS-12-192. September 1971.
S. McCaskill. O.l^. «nd R.A. Wenley. I nifilter (Collecting System for Cotton-pin Waste Materials.
l.'.S. Department of Agriculture, Agriculture Research Service. New Orleans, La. ARS-S-144.
September 1976.
(;. PHrnell. C.B., Jr. and Roy V. Baker. Particulute Emissions of a CoUon Gin 'r, the Texas Stripper
Area. I .S. Department of Agriculture, Agriculture Research Servir- ^ ashinplnn, D.C.
Production Hesearch Report ^o. 149. May 1973.
7. Kirk, I. W.. T.E. TX right, and K.I1. Read. Particulale Emissions from CumiiiiTcidl Cotton (/inniiifc
(Jperations. Southwestern Cotton Ginning Research Laboruory, Mcsilia Park, New Mexiet .
Presented at ASAE 1V76 Winter Meeting, Chicago. Illinois. Decerrbrr 1976.
H. Cotton (rin Emission Test*. Marina Gin, Prndui'ers Cotton Oil Company. .Vlonina, Ari-'.orn
National Enfor<-ement Investigations Center, Denver, Colo, and EPA Hegion IX. Public ation No
KPA-330/2-78-008. May l<»7t!.
9. Kmi!
-------
6.4 FEFO AND GRAIN MILLS AND ELEVATORS
ti.4.1
Cram elevators are buildings in which grains arc gathered, *tored, ai discharged for . :«*. further
processing, or shipping. They are classified as "country, ""terminal, "and "export" elevators, acrorfj ing
tu their purpose and location. At country elevators, grains are unloaded, weighed, and p lured in
slorjge ,is they are received from farmers residing within about a 20-mile radius of the elevator. In
addition, counlrv ele\ alors bometimcs dry or clean grain before it is shipped tu terminal elevators or
proces.sui .
Terminal elevaloi s receive most of t heir «r-iin from country elevators anil ship to pi cccssurs. olher
terminal*, and exporters. The primary functions of terminal elevators are to store large quantities of
grain without detenot atton and to dry, clean, sort, and blend different grades of grain to inrvl buyer
specifications.
Kxporl elc»ulor< are similar ly terminal elevators except lhat the) muinlv load gi j-n on ship" for;
export.
Professing of grain in mills and feed plants ranges from very simple mixing steps lo comulex
industrial processes. Included are such diverge processes as. (] Simple mixinp operations in feed r»ii!l«,
i2) grain milling in flour mills. (3) solvent extracting in .soybean processing plants, «nd (4) a complex
series of processing steps in a corn wet-milling plant.
6.4.2 Emissions and Controls
Grain handling, milling, and pro. ("-sing include a variety of operations from the initial receipt of
the grain at either a country or terminal elevator to the deli very of a finished product. Flour, livestock
feed, soybean oil, and corn syrup are among 'he products produced fror,. plants in the grain and feed
industry. Emissions from the feed and grain industry ran be separated into two general areas, those
occurring at ^rain elevators and those occurring at grain processing operations.
6.4.2.1 Gtain Elevators • Grain elevator emission? can occur from many different operations in the
elevator including unloading (receiving), loading (shipping), drying, cleaning, headhouse (legs),
tunnel belt, gallery belt, and belt trippers. Emission factor* for these operations at terminal, country,
and export elevators are presented in Table 6.4- J. All of these emission factors are approximate average
values intended lo reflect a variety of grain types. Actual emission factors for a specific source may '.it
considerably different, depending on the type of grain, i.e., corn, soybeans, wheat. and olher factors
such as grain quality.
The emission factors ?hov\n in Table 6.4-1 represent the amount of dust generated per ton of grain
processed through each of the designated operations (i.e., uncontrolled emission factor •.). A mounts of
grain processed through each of these operations in a f iven elevator are dependent on such factors us
the amount of grain turned (interbin transfer), amount dryed, and amount cleaned, etc. Because the
• mount of grain passing through eaih operation is often difficult to drlermine. it may be more useful
to express the emission factors in terms of the c mount of grain shipped or received, assuming ihese
amounts urt* about the same over the long term. E.-nission factors from Table 6. 4-1 have been modified
accordingly and arr shown in Table 6.4-2 along with ihe appropriate miiitiplici »' it was used asrepre-
sentaiive of typical ratios of throughput at each operation to iheflmount of grain shipped or received.
This ratio is an approximate value based on average values for turning, cleaning, and drying in each
4/77 Food and A'ri'Millur&l Inrliitslr 6.4-1
-------
type of el* vat or. However, because operating practices in individual elevator* are differ -u, these!
ratios, like the basic emission factors themselves, are more valid w^en applied to a group of elevators
rilher than individual elevators.
Table 6.4-1. PARTICULATE EMISSION FACTORS
FOR UNCONTROLLED GRAIN ELEVATORS
EMISSION FACTOR RATING: &
I
Emission factor3
Type of source
Ib/tor I
Ten.iinal elevators
Unloaded (receiving!
Loading (shipping)
Removal from bins (tunnel beltl
Dryingb
Clfiani; 5°
Headhouse (le^s)
Tripper (gallery belt)
Country elevators
Unloading (receiving)
Loading (shipping)
Removal from bins
Dryingb
Cleaning0
Headhouse \iegs)
Export elevators
kg/MT
1.0
0.3
1.4
1.1
2.0
1.5
1.0
0.6
0.3
1.0
0.7
30
1.5
0,5
0.2
1.7
0.6
1.5
1.8
0.5
0.3
0.2
0.5
0.4
1.5
0.8
Unloading {receiving)
Loading (shipping)
Removal from bins (tunnel belt)
Drying"
Cleaning'
Headhouse (legs)
Tripper (gallery belts)
1.0 I 0.5
1.0
1.4
1.1
3.0
'.5
1.0
1
0.5
0.7
0.5
1.D
0.8
0.5
'Emission factors are in terms of pounjb of dusi eniitted p»r ton of
yrain processed by each operation. Most o. the fruors for terminal
arid axport elsvators ars b«bed un Reference 1. Emission factors
for drying are based on RelereiH-es 2 and 3. The orrvssio factors
lor country elevators are basec 0,1 Reference 1 and specir'C country
elavsror test data m Reference* 4 through. 9.
"Emission factois 'o' dryinrj ars b.i«d on 1.8 Ib/Ton for reck dryers
and 0.3 Ib/lon for colunn d-yers pi orated on th« basis of distribu-
tion of these two types of dwerc in ejch elevator category, as
Discussed m RRferpnce 3.
cEmisiion factor of 3.0 far cleaning 13 nr average value which may
range from < 0.5 lor vvheat up to 6.O for corn.
The factors in Tables 6.4-1 or 6.4-2 should not be added together in an attempt to obtain a single
emission faclur value fur grain elevator;: because in most eVvaiura gome of the operations are
equipped with control devices and some are not. Therefore, any estimation of emissions must he
directed to each operation anJ its ansociateri control device, rather than the elevator as a whole, unless
rhe purpose was to estimate total potential (i.e., uncontrolled) emissions. An example ol the UH" of
emission f*rtnrs in making an emission inventory in contained in Reference 3.
6.1-2
EMISSION FACTORS
•I/'
-------
Table 6.4 2. PARTICULATE EMISSION FACTORS FOR GRAIN ELEVATORS BASED ON
AMOUNT OF GRAIN RECEIVED OR SHIPPED"
1 Emission factor.
Type of soLrce ib-'ton processed
Terminal elevators
UnlnJD.ng (recriv rg) 1.0
Loading (shipping) . 0.3
TyrJicjl ratio of tons processed j
to 'ons rpi:pivpti o shif>p?d°
1.0
1 D
Removal horn bins ( 10
0 1
0.2
30
i 17
Country e t»vatoi:> •
Unload ng (recei.irjl ! 05 11
Loading (sh. CPU'S 1 0-3 ' 1.0
Removal have been utilized at many elevators on almost all types of operations. Unfortunately, some
MG'ir, in grain elevators p. < -enl control p. oblema. Control of loudout operations is difficult because
of the problem of containment of the emissions. Probably the most difficult operation to control,
b'ca.ise of the large flow ratf and high moisture con'er.t of the exhaual gases, is the dryers. Screen-
houses or continuously vacuumed scieen t->stem« are aM-jlahte for reducing dryer emissions and ha' i-
beer applied at se.eral facilities. Devilled deseriptioncol'dusl control svs terns for gruin L-levaiur opcr-
are contained in Reference 2.
6.4.? 2 Grain Processing Operations • Grain processing operations include many of the operations
performed in a grain elevator in addition lu milling and processing of the grain. Emission factors for
different grain milling and proct^ying operations arc presented in Table 6.4-3, Brief discussions of
thciit dii:'r-rt:ni operation* and the methods used for arriving at the emission factor Dallies shown in
Talil'* 6.4-3 are p-esented below.
I./T-
KOIH! iniil Agricultural Iniluslrv
(>.
-------
Tiblt 6.4-3. PARTICULATE EMISSION FACTORS
FOR GRAIN PROCESSING OPERATIONS1.2.3
EMISSION FACTOR RATING: D
Type of source
raed mills
Receiving
Shipping
Handling
Grinding
Emission lactora.D
(uncontrolled except wi-wre indicated)
Ib/ton
kg/MT
1.30 i 065
0.50
3.00
0.25
1.50
0.10C 0.05C
Pellet coolers ; 0.1 nc 0.05C
Wheat mills
Receiving | 1.00
0/^0
Precleaning and handling ' 5.00 2.50
Cleaning house
Milihouse
Durum mills
Receiving
70.00
1.00
Precleaning and handling 5.00
Cleaning house
Milihouse
Rye milling
Receiving
Precleaning and ha. idling
Clr.sning house
Milihouse
Dry corn milling
Receiving
Drying
Precleaning and handling
Cleaning house
Degerming and mil'ing
Oat milling
Total
Rice milling
Receiving
Handling and precleanmg
Drying
Cleaning and millhouse
-
1.00
35.00
0.50
2.50
0.50
5.00 2,50
70.00
1.00
0.50
5.00
6.00
2.50d
0.64
500
Soybocn mills
i
Receiving i.60
Handling 5.00
Cleaning
Drying
Crack- 19 and deiiulling
Hull grinding
7.20
3.30
J500
0.50
0.25
2.50
3.00
1.250
0.32
2.50
0.80
2.50
3.60
1.65
2.00 j 1.00
6.4-4
KM I SSI ON FACTORS
4/77
-------
Tatfe 6.4-3 (continued). PARTICULATE EMISSION FACTORS
FOR GRAIN PROCESSING OPERATIONSl.2.3
EMISSION FACTOR RAT5NG: 0
Type of source
Bean conditioning
flaking
Meal dryer
Meal cooler
Bulk loadinc
Corn wet milling
Receiving
Handling
Cleaning
Dryers
Bulk loading
Emission factor8. b
(uncontrolled except where indicated)
Ib/ton
0.10
0.57
1.50
1.80
0.27
1.00
6.00
6.00
-
-
kg/MT
0.05
0.29
0.75
0.90
0.14
0.50
2.50
3.00
-
'Emission factor* art expressed in terms of pounds jf dust emimd per ton of grain
entering the plant (i.e., received), which ii not necessarily the tarn) as the amount
of material processed by each operation.
indicate insufficient information.
cConirclled emission factor (controlled with cyclones).
Controlled «mi«ion factor. (Thti represents several sources ir> one plant; some
controlled with cyclone* and others controlled with f«h-ic filters.}
Emiaeion factor data for feed mill operations are sparse. This is partly due to the fact that mar.y
ingredients, whole grain and other dusty materials (bran, dehydrated alfalfa, etc.), are received by
^th truck and rail and several unloading methods are employed. However, because some feed mill
operations ('handling, shipping, and receiving are similar to operations in a grain elevator, an emis-
sion factor for each of these different operations was estimate-] oil that basis. The remaining
operations are based on information in Reference 2.
Three emission areas for wheat mill processing operation* are prnm receiving and handling, clean-
ing house, and milling operations. Data from Reference 1 a r user! In estimate emissions factors for
grain receiving and handling. Data for the cleaning house are insufficient to estimate an emission
factor, and information contained in Reference 2 is used to estimate the emission factor for milling
operations. The IB -go emission factor ior the mil ling operation in somewhat misleading because almost
all of the sources involved are equipped H'ith control devices to prevent product lotses; fabric fillers
are widely used for this purpose.
. Therefore, most
Operation* for durum mills and rye milling are similar to those of wheat .n
of these emission fuctois are assumed eq-'il to those for wheat mill operations.
The grain unloading, handling, and cleaning operations for dry corn milling an; similar to those in
other grain mills, but the subsequent operations are somewhat different. Also, some drying of corn
received at the mill may b" necessary prior to storage. An estimate of the emission factor for drying is
obtained from Referent*- 2. Insufficient information is available to estimate ^miaaion fartorf. for
degerming and milling.
Information necessary to estimate emissions irom oat milling is tinavailnble, and no ,m..,su>n
factor for another grain is considered applicable because oats .ire reported to be dustier than man)
other grains. The only emission factor data available are for controlled emissions.- An overall con-
trolled emission factor of 2.5 Ib/ton i-i calculated from these data.
4/77
Food and Agricultural Industry
6.4-5
-------
Emission factors for rice milling are bused rm those for similar operation* in other grain handling
facilities. Insufficient information is available to estimate emission factors for drying, cleaning, and
mill house operation!).
Information container* in Reference 2 is used to estimate emission factors for soybean mills.
Emissions information on corn wet-milling IB unavailable in most raHes due to the wide variety of
products and the diversity of operations. Receiving, handling, and cleaning operations emission
factors are assumed to be similar tu lho«e for dry corn milling.
Many of the operations performed in grail, milling and procrsmng plants are the same as those in
grain elevators, so the control methods are similar. As in the ran? o: grain ele>ators. these plantsoften
use cyclones or fabric filttrs to control e.Ti -sions from the grain handling operations (e.g.', unloading,
legM, cleaners, etc.). These same devices are also often used to control emissions from other processing
operations; a good example of this is theextensive use of fabric filters in flour mills. !Iowe\r-r, therrnre
also certain operations within some milling operations thtt are not amenable to use of these de1. ice.".
Therefore, wet scrubbers have found some application, particularly where the effluent gasstream hat*
• high moisture con tent. Certain other operations hive been found to be especially difficult to control,
such as rotary dryers in wet corn mills. Description* of the emission control systems that have been
applied to operations within the grain milling and jirocenfting indu
-------
8. Delgra, F.J. Grain Handling Dust Collection Systems Evaluation for Farmer* Ek valor Company,
Minot, North Dakota. Report lubmitlrd lo North Dakota State Department of Health, by
Pollution Curbi, Inc. St. Paul, Minnesota. August 28, 1972.
9. Delgea. F.J. Cyclone Emission and Efficiency, Evaluation. Report submitted to iNorlh Dakota
Stale Department of Health on tests al an elevalot in Thompson. North Dakota, by Pollution
Curb*. Inc. Si. Paul, Minnesota. March 10, 1972.
10. Schrag. M.P. el «l. Source Test Evaluation for Feed and Grain InduKtry. Prepared by Midnest
Rcsearrh Inalitute, Kansas City, Mo., for Environmental Protection Agency, Research T'riangle
Park. INC., und^r Contract No. 68-02-1403, Tt«k Order No. 28. December 1976. Publication No.
r,PA.450/3-76-043.
4/77 Food and Agricultural Industry 6.1-7
-------
6.5 FERMENTATION
6.5.1 Process Description1
For fhe purpose of this report only !he fermentation industries associated with food will be considered Tim
includes the production of beer, whiskey, and wine.
Tne manufacturing p-ncess f>. each of these is similar. The four main brewing p'odtk'iion stages and their
respective sub-stages are: (1) brewhouse operations, which include (a) malting of the barley, (b) addition of
adjuncts (corn, grits, and rice) to barley mash, (c) conversion of starch in barley and adjuncts to malms? sugar by
eruynunc proizi-es, (d) separation 01 wort from grain by straining, and (c) hopp'ng arid boiling of the -vurt,(2l
fermentation, which mc'ud;s (a) cooling of tlie wurt, (b) additional yeast cultures, (c) fcrrnciitjuon lor 7 lo 10
days, (d) rerrovdi of settled y:ast, and (e) filtration and carbonation; (3) aging, which lasts from I to 2
under refr.get'ation; and (4) packaging, which includes (a) boilhng-pasteurization, an
-------
TibtL 65-1. EMISSION FACTORS FOR FERMENTATION PROCESSES
EMISSION FACTOR RATING: E
l
Participates
I Harticu_iates_
Type ol product j Ib/ton I kg'MT
Hydrocarbons
Ib/lon kg/MT
Betr
G.a,n healing- See Subsection 6 . 5 .1
Uryinq '.p«>nt grains, elc ''
Whiskey
Grain handling3 .3 1.5 . -
Drying spent grams, ttc.a 525. NA ' NA
Aging j '• '"f • 0.024"
Wl"e I See Subsection 6.5.2
6esed on pulton nn uidinlirix:' >i^ny
bNo emission factor avuilahie. bJi emiss ins do occur
^"Pourds a^» yew per ba;iel ol whiskey stored.
^Kilograms per year per lit^i o' wfi isk«y ttor«d.
*No significant emissions
Rffcrencrs for Sec lion 6.5
|. Air PolluU'i' I nihMon h;n.'ior> Kiiui Report KcMinri'cs Rcsciircli, Inj. Rcslon. V». Prepared for National
Mr Pollutior. C'onlrul Adni'.nistration. Durham. NC . under t'onlract Nunbei CCA 22-69-1 19. April 1^70.
.. Shrevc, R N Ch.L'iniLjl Pn.Kcsb Industries, ?rd Id New Vork, McGraw-Hill Book Company. 1^67. p.
591 608.
h.5 2 (MISSION |• \("H)K> 2;71
-------
6.5.1. BEER MAKING
6.b.l.l General1"3
Beer is a beverage of low alcoholic content (2-7 percent)
made by the fermentation of malted starchy cereal grains. Barley
is the principal grain used. The production of beer is carried out
in four major stages, brewhouse operations, fermentatirr., aging and
packaging. These processes are shown in Figure 6.5.1-1.
Brewhouse operations include malting of the barley, addition
of adjuncts to th». barley mash, conversion of the starch in the
barley and adjuncts to maltose sugar, separation of wort from the
grain, and hopping and boiling of the wort.
In malting, barley is continuously moistened to cause it to
germinate. With germination, enzymes are formed which break down
starches and proteins to less complex water soluble compounds. The
malted barley is dried to arrest the enzyme formation and is ground
iu a malt or roll mill. Adjuncts, consistinp of other grains
(ground aad unmalted), sugars and syrups, are added to the ground
malted barley and, with a suitable amount oT water, are charged to
the mash tun (tank-like vessel). Conversion of the complex
carbohydrates (starch and sugars) and proteins to simpler water
soluble fermentable compounds by means of enzyme action takes
place in the mash tun, a process called mashing. The mash is sent
to a filter press or straining tub (lauter tan) where the wort
(unfermented beer) is separated from the spent grain solids. Hops
are added to the wort in a brew kettle, where the wort is boiled
one and a half to three hours to extract essential substances from
the hops, to concentrate the wort, and to destroy *he malt enzymes.
The wore is strained to remove hops, and sludge is removed by a
filter o: centrifuge.
Wort is cooled to 10°C (50°F) or lower. During cooling, it
absorbs air necessary to st&rt fermentation. The yeast is added
and mixed with the wort in line to the fermentation starter tanks.
Fermentation, the conversion of the simple sugars in the wort to
ethanol and carbon diox.ide, is completed in a closed ferraenter.
The carbon dioxide gas released by the fermentation is collected
and later used for carbonating the beer. Cooling to maintain
proper fermentation temperature is required because the reaction is
exothermic.
After fernentation is complete, beer is stored to age for
several weeks at 0°C (32°F) iu large closed tanks. It is recar-
bonated, pumped through a pulp filter, pasteurized at 60eC (140°F)
to make it biologically stable, and packaged in bottles ,:nd cans.
Beer put in kfgs for draft sale is not pasteurized.
A/81 Food and Agricultural Industry 6.5.1-1
-------
Bnrley \ / Adjuncts
^ ,,, y
{ Malting i { Cereal
V.... -••' V cooker
T
/ Dryer
^--y-
f Malt
V^ mill
^
_.)
7
y
XiGsh "T
tun J
Filter
p
spent
grain
Brew
kettln
\ ^
J ^/
Hops
>
ainer Jp,
Strainer
I Spent 1
I hops 1
L»^———I
Scorage
Figure 6.5.1-1. Plow dlagrun of a beer making process.
2-7
6.5.1.2 Emirsions and Controls
The major emissions from baer making i-T»d their sources are
parttculates rind volatile organics, mainly etnanol, from spent
grain drying, and partlculates from grain handling. Volatile
organicB (VOC) from fermentation are negligible, and they are
f igitive because the fertnenters are closed to provide for collecting
rarhon dioxtdt; Ochsr brewery processes are ininor sources of
volatile organics, ethenul and related compounds, such as boiling
6.5.1-2
EMIaSION FACTORS
4/81
-------
wort in the brew kettle and raalt drying. An estimate of these
emissions is not available.
Fugitive particulate omissions from grain handling and milling
at breweries are reduced by operating in well ventilated, low
pressure conditions. At grain handling and milling operations,
fabric filters are roost often used for dust collection. Organics
and organic participate matter from spent grain drying can be
controlled by r,:i.xing fhe Jryer exhaust with the combustion air of a
boiler. A centrifugal fan wet scrubber is the most commonly used
control.
TABLe! 6.5.1-1. EMISSION FACTORS FOR BEER BREWING*
EMISSION FACTOR RATW-: D
Source
Grain handling
Br^w kettle
Spent grain drying
Cooling units
Fermentation
Participate
1.5 (3)b
2-5 (5)b
Volatile Organic Compounds
NAC
1.31 (2.63)d
V C
KA
e
Neg
Expressed in terms of kg/10 g fib/ton) of grain handled. Blanks
.indicate no emissions.
Reference 6.
£
Factors not aw-i Vihle, hut negligible amounts of ethanol emissions
,ai>; suspected.
Reference 4. Mostly ethanol.
p rf
Negligible amounts of ethanni, ethyl ar.etate, isopropyl alcohol,
n-propyl alcohol, isoarayl alcohol, and isoamyl acetate emissions
are suspected.
Ref erences for Section 6.1) 1
1. H.E, HgSyrup, "Beer and 3rewinc;". Kirk-Othmer Encyclopedia of
Chemical Technology, Volume "), John Wiley and Sons, Inc.,
"New Ynrk, 1964, pp. 297-338.
2. R. Nnrris Shrive, Chemical Process Industries , 3rd Ed.,
McCiraw-Hill Book Company, New York, 1967, pp. f>03-605.
I. E.G. C.ivanaugh, et al., Hydrocarbon PollutavTfs from Stationary
, iiPA-600/7-77-110, U.S. Rnvlronmenta!. Protection Agency,
"Research Triangle Park, NC, September 1977.
Kood and Agricultural InduatT'y 6.5.1-3
-------
4. H.W. Bucon, et al., Volatile Organic Compound (VQC) Species
Data Manual, Second Edition, EPA-450/4-80-015, U.S. Environmental
Protection Agency, Research Triangle Park, NC„ December 1978.
5. Melvin W. First, et al.. "Control of Ooors and Aerosols from
Spent Grain Dryers", Journal of the Air Pollution Con:rol
Association, _24_(7): 653-659, July 1974.
6. AF.ROS Manual Series, Volume V: AEROS Manual of Codes,
E!PA^450/2-76-005, U.S. Environmental Protection Agency, Research
Triangle Park, NC, April 197b.
7. Peter N, ForTira, Controlled and Uncontrolled Fmisston Rates
and Applicable limitations for Eighty Processes, EPA-340/1-78-OJ4,
U.S. Environmental Protection Agency, Researcn Triangle Park,
NC, April 1978.
6.5.1-'* EMISSION FACTORS 4/31
-------
6.5.2 WINE MAKING
6.5.2.1 General1'4
Wine is mrdz by the fermentation of the juice of certain fruits,
chiefly grapes. The grapes ar*:. harvested when the sugar content ij
ri^ht. for the de,s ired product, generally around 20 percent sugar by
weight . The industry term for grap- sugar content is Degrees Brix, with
1 "Brix equal to 1 gram of sugar ptr 100 grans of juice.
The harvested graphs are stemmed and crushed, and the juice is
extracted. Suifurous acid, potassium metabisulf ite or liquefied S02 Is
used to produce 50 to 200 mg of S02 , which is added to inhibit the
growth of undesirable bacteria and yeasts. For the makiriv of a white
vine, the skins and solids are removed from the juice before fermen-
tation. For a ved wine, the skins ana solids, which color the wine,
left in the Juice through the fermentation stage. The pulpy mixture of
Juice, skins and so: ids is called a "must".
White wine is generally fermented at about 52°F (11°C), and r<=>d
wine at about 80°F (27°C). Fermentation takes a week to ten days for
white wine and about two weeks for red. Fermp.ntation ir. conducted in
tanks ranging in size from several thousand gallons to larger than
500,000 gallons.
The sugar of the fru.lt juice is converted into ethanol by the
reaction:
06 •* 2 C2H5OH + 2 CC2
(sup.ar) (ethanol)
Tills process takes place in the presence of a specially cultivated
yeast. Theoretically, the yiold of ethanol should be 5.1.1 percent by
weight of the initial sugar. The actual yield is found tc be around 47
percent. The remaining sugar is lost as alcohol or byproducts of complax
chemical mechanisms, or it remains in the wine as the result of incomplete
fermentation.
When fermentation is complete, the wine goes through a finishing
process for clarification. Common clarification procedures are filtr-
ation, fining refrigeration, pasteurization and aging. The wins is then
bottled, corked or capped, labeled and cased. The iMner red and wh^te
table wines are aged in the botule.
i 2
6.5.2.2 Emissions and Controls '
Large amo-ints of CC>2 gas are liberated by the fermentation process.
The gas is passed into the atmosphere through a vent in the top rl the
tank. Ethanol losses occur chiefly as a result of entralnment in the
I oo..">.J-
-------
C02. Factors which affect the amount of ethanol lost during fermen-
tation are temperature of fermentation, initial sugar content, and
whether a juice or a must is being fermented (i.e., a white or red wine
being made).
Emission factors for wine making are given in Table 6.5.2-1.
These enission factors are for juice fermentation (white wine) with an
initial sugir content of 20 °3rix. Emission factors are gi"en for two
temperatures rnmmoniy used for fermentation.
Table 6.5.2-1. ETHANOL EMISSION FACTORS FOR UNCONTROLLED WINE
FERMENTATION
EMISSION FACTOR RATING: B
Ethanol Emissions '
•7ermeatati
T = fermentation temperature., °?
B = initial su-^ar conte: [, °Brix
C = correction term, 0 (zero) for white wine or
2.4 lb/103 gal for red wine
Although no testing has been done on emissions from wine fermen-
tation withouc grapes, -LC is expected that eth;;nol is dlsn emitted fron
these operations.
i \( TOH> 2/
-------
There is potential alcohol lose at various working and storage
stages in the production process. Also, fugitive alcohol emissions
could occur from disposal of fermentation solids. EtHanoi is considered
to be a reactive precursor of photochemical oxidants (ozone}. Emissions
would be highest during the middle of the fermentation season and would
taper off towards the end. Since wine facilities are concentrated in
certain areas, these artas would be mere affected.
Currently, the wine inc'jstry uses no means to control the ethanol
lost during fermentation.
References for Section 6.5.2
1. Source Test Report and Evaluation on Emissions from a
Fermentation Tank at E. & J. Gallo Winery, C-8-050, California Air
Resources Bo?rd, Sacramento, CA, October 31, 1978.
2. H, W. Zimmerman, et al., "Alcohol Losses from Entrairment in
Carbon Dioxide Evolved during Fermentation", American Journal
of Enology. 15.:63-68, 1964.
3. R. N. Shreve, Chemical Process Industries. 3rd Ed.,
McGraw-Hill Book Company, New York, 1967, pp. 591-608.
4. M. A. Amerxne, "Wine". Kirk-Othmer Encyclopedia of Chemical
Technology, Volume 22, John Wiley and Sons, Inc., Naw York, 3
pp. 307-334.
2/HO F«»<»«l iiinl Vjfririihural hiiliiMr\ (».." 2-
-------
6,* FISH PROCESSING
6.6.1 Process Description
Fish preceding includes the canning of fiih and the manufacturing of by-products such as fish oil
and fuhmeal. TV. c manufacturing of fich oil and fish meal arc knuwn a* reduction processes. A general-
ii»'d fish processing operation IB presented in Figure 6.6-1 .
Two types of canning operations are used. One is the "we* fish" method in which trimmed and
eviscerated fieri are cooked iirv :\y in open conn. The other operation in the "pre-cooked" process in
which eviscerated fish are cooked whol; and portions are hand selected and packed into carm. The pre-
cooked procesa i» used primarily for larger fieh eu^n as tuna.
By-product manufacture of rejected whole fish and scrap requires several steps. 1- irst, the fish scrap
mixture from the canning line is charged to a live steam cooker. After the material leaves the cooker,
it is presst'd to remove water and oil. The resulting press cake ii broken up and dried in a rotary drier.
T*o types of driers are used to dry the press cake: direct-fired and steam-lube driers. Direct-fired
drien contain a stationary firebox ahead of the rotating section. The hot products of combustion from
the firebox are mixed with air and wet .neal inside the rotating section of the. drier. Exhaust gases are
generally vented to a cyclone separator to recover much of the entrained fish meal product. Stecm-
tube driers contain a cylindrical bank of rotating tubes through which hot, pressurised steam is
passed. Heat is indirectly transferred to the meal and the tir from the hot tubes. As with direct-fired
driers, the exhaust gases are vented to a cyclone for product recovery.
6.r> 2 ELiieetons and Controls
smoke and dust can be a problem, odors are the moat objectionable emissions from fish
processing plants. By-product manufacture results in more of these odorous contaminants than
canner) operation* because at the greater stale of decompusitio'i of the matcria1'' processed In gener-
al, highly decayed feedstocks produce greate* concentrations of odors than do fresh feedstocks.
The largest odor sources are the fish meal driers. Usually, rlireet-firerl driers emit more odors than
steam-tube driers. Direct-fired drien will also emit dmoke, particular), if t'ie driers are operated
under high temperature conditions. Cyclones are frequently employed oi. drier exhaust BUSES for
product recovery and paniculate emission control.
Odorou i Runes from reduction uokera consist primarily of hydrogen sulfide [H2S] and trimethyl-
amine [(CH j),N]. Odor 6 from reduction cookers are emitted in volumes appreciably lesc than from fish
meal tirien. There are virtually no participate emissions from reduction rookers.
Some O'lors are also produced hy the canning processes. Generally, the pre-cooked process emits
less cdorout gase- than the wet-fish process. This is i^ipuae in the prc-cucked process, the odorous
exhaust, gsses are trLppcd in the tuckers, wherens in the wet-fish process, the steam and odorous
offgases ate commonly vented directly to the atmosphere
Fish cannery and fish reduction odors can be controlled with a'terbnrners, ^rilorinalor-serubbers,
and condensers. Afterburnem are must affective, providing virtually 100 lercent odor control; how-
ever they a -e r.istly from a fuel-use standpoint. Chlbrinator-Riruhbers ha>e been found to be 95 lo99
percent e.'fpctne in controlling odorp from cookers aiid driers. Condensers are the lecsl effective
control device. Generally, centrifugal co'l^ct'irn are satisfactory (or conlrolling exceeeive dust emia-
lions fiMm driers.
Emispion factors For fish proce'^in^; are presented in Table ft. 6-1.
4/77 Food nnd Agricultural Industry 6.6-1
-------
FISH
ODOHS
LANNED
FISH
OOORS
**)
n
H
O
FISH SCRAP-
STEAM <
EXHAUST GASES
LIVE STEAM COOKER
COOKED
SCRAP
f
PRESS
PRESS
CAKE.
\
I PRESS
WATER
SOLIDS
SEPARUICh
SO LI OS
CONDENJER
CENTRIFUGE
LIQUIDS
ROTARY HSHMFAI
DRVER
EXHAUST GASES AMD
ENTRAINED FISH ME; I
DRIED FISH MEAL
' SOLUA91ES
WATER AND
" :3LUBIES
. FIS,,l)JL
PARTICIPATE )
ANDQDQRS C
RECOVERED FISH MEAL
TO FSHMEAL
Figure 6.6-1. A generalized fish processing flow diagram.
-------
TABLE 6.6-1. EMISSION FACTORS FOR FISH PROCESSING PLANTS
EMISSION FACTOR RATING: C
Emission source
Cookers , Banning
Cookers, fls'u scrap
Fresh i'lsh
Stale fish
Steam tube dryers
Direct fired dryers
^articulates
kg/Mg
Nega
Nega
Nega
2.5
4d
Ib/ton
Nega
Nega
Nega
5d
8*
Trine thylamlne
[(CHlhNj
kg/Mg
NAb
0.15C
1.75C
NAd
NAd
Ib/ton
NAb
0.3C
3.5C
NAd
NAd
Hydrogun uulfide
fH7S]
k>',/Mg
NAb
0.005C
0.10C
NAd
NAd
Ib/ton
NAb
O.C1C
0.2C
NAd
NAd
aRef«rence 1. Factors are for uncontrolled emissions, before cyclone.
Neg - negligible. NA - not available.
* Although It Is known that odors arc emitted from canning cookers,
quantitative estimates are not available.
cReference 2.
dReference 1.
References for Section 6.6
1. Air Pollution Engineering Manual, Second Edition, AP-40, U. S. Environ-
mental Protection Agency, Research Triangle Park, NC, May 1973. Out of
Print.
2. W. Summer, Methods of Air Deodorlzatloat New York, E1.sevler Publishing
Conpany, 196?.
4/77
d and >\gricultural Industry
-------
6.7 MEAT SMOKEHOUSES
6.7.1 Process Description1
Smoking ib j diffusion process in which food products are exposed lo an atmosphere of hardwood smoke.
causing various organic compounds lo be absorbed by the food Smoke is produced coimneiically in the United
Stales by three major methods: (1) by burning dampened sawdu:! (20 lo 40 percent moisture), (2) by burning
dry sawdust (j to 9 percent moisture) continuously, und ( >i oy tricliun. Burning dampened sawdust and
kiln-dried sawdust ^re the most wijrly used methods. Most l.uge. modern, production meat smokehouses jre the
recirculjling type, in which smoke is circulated nt reasonably high temperatures throughoot the smokehouse
6.7.2 Emissions and Controls1
F.nibsions Irom smokehouses are generated from the burning hardwood rjlhcr man from the conked product
itself. Based on approximately 1 10 pounds of meat sinoked per pm'nd of wood burned (I 10 kilograms of meal
per kilogram of wood burned), emission factors hjvc been derived for meat smoking and arc presented in Table
67-1
Emissions from meal smoking are dependent on several factors, including the type of wood- the type of smoke
generator, the moistuie content of the wood, the ait supply, and the amount of smoke recirculaled. Both
low-voltage electrostatic precipilators and direct-fired afteroumers may be used lo reduce paniculate arid organic
emissions. These controlled emission factors have also been shown in Table 6.7-'.
Table 6.7-1. EMISSION FACTORS FOR MI-ATSMOKlNG1-"
EMISSION FACTOR RATING: O
Polluidnt
Particulars
Carbon monoxide
Hydrocarbons (CH4)
Aldehydes (HCHO;
Organic acids (acetic)
Uncootioiled
Ib'ton of m?at
0.3
0.6
0.07
0.08
ky/MT of meat
0 16
0.3
0.035
004
Controlled0
Ib'ton of meal
0.1
Negd
Neg
0.05
02 0.10 0.1
kg/MT of must
005
Neg
Neg
0025
005
or, 110 pounds of meal tmuktd p*r pound of wood burned 1110 kg m«at/Vg wood t/umedi
''References 7. 3, and section on chaicoal production
cl'onUols consist of either • wet collector and low-voltage precipitate in STI^S. or a direct fired afterburner
'V'ith afterburner
2/72
Food and Agricultural Industry
6.7 I
-------
References for Section 6.7
I. Air Pollutant Emission Factors, Final Report. Resources Research. Inc. Reston, Va. Prepared lor Nations!
Air Pollution Control Administration, Durham, N.C., undei Cmloct Number CPA-J2-69-I 19. April 1970
2. Carter, I.'. Private cnrmnunica.'ion between Maryland State Department of Health and Resources Resrnrch.
Incorporated. November 2 I, 1969.
.V Polglase, W.L., H.F. Dey, and R.T. WalsJi. Smokehouses. In Air Pollution Engineering Manna' Panielson, J
A (ed ). U.S. DHEW, PHS. Ntlionat Center for Air Pollution Control CincinnaK Ohio. Publication Number
999-AIMO. 1967. p. 750-755.
6.7-2 EMISSION FACTORS 2/72
-------
6.8 AMMOVIUM NITRATE
6.8.1 General1"2
Ammonium nitrate (KH4N03) l.s produced by neutralizing nitric acid with
ammonia. The reaction can be carried out at atmospheric pressure or at
presfures up to 410 kPa (45 peig) and at temperatures between 405 and 458K
(270 - 3'j5*F). An 83 weight percent solution of ammonium nitrate product
is produced when concentrated nitric acid (56 - 60 weight percent) is
..ombined w'ith gaseous ammonia in a ratio of from 3.55 to 3.71 to 1, by
weight. Whtn solidified, amnoniun nitrate is a hygroscopic colorless
solid.
Ammonium nitratp is marketed in several fortrs, depending upon its use.
The solution formed rrom th« neutralization of acid and ammonia may be sold
as a fertilizer, generally in combination with urea. The solution may be
further concentrated to form a S5 to 99.5 percent ammonium nitrate taelt for
use in solids formation processes. Solid ammonium nitrate may be produced
by prilling, graining, granulation or crystallization. In addition, prills
can be produced in either high or Inw density form, depending on the
concentration of the melt. High density prills, granules and crystals are
used as fertilizer. Ammorlum nitrate grains are used solely i.i explosives.
Low density prills ':aii be ujed as either.
The process for manufacturing ammonium nitrate can contain up to seven
major unit operations. These operating steps, shown in Figure 6.8-1, are
solution formation or synthesis, solution concentration, solids formation,
solids finishing, solids screening, solids coating, and bagging and/or bulk
shipping. In some cases, solutions may be blended for marketing as liquid
fertilizers.
AMMONIA
• UUIMVt
1 t 1
SOLUTION _H SOLUTION ^ SOLIDS SOUPS SOLIDS SOLIDS
FORMAT'ON f|JONCiNT1lATIOII FORMATION FINISHING SCREENING7 "*" COATING "
[ DFFSIZE RECYCLE \
SOLUTIONS jTn'moT;
•-
»-
~~| BLENDING i
BAGGfNG
IULK
SHIPPING
BULK
SHIPPING
ADDITIVE MAV BE ADDED ?IFORE. DURING. OR AFTIR CONCENTRATION
7$C«EN.ND MAY IE BEFORE OR AFTfR SOLIDS FINISHING
Figure. 6.8-1. Airancniun nitrate manufacturing operations.
The number of operating steps •zmployed is determined by the dcsireu
end product. For example, plants producing ammonium nitrate solutions
alone use only the solution formation, solution blending and bulk shipping
1/84
Food and Agricultural Industry
6.8-1
-------
operations. Plants producing a solid aDiraonium nitrate product can employ
all of the operations.
All ammonium nitrate plants produce ar aqueous ammonium nitrate
solution through the reaction of ammonia and nitric acid in a ntutralizer.
To produce a solid product, the ammonium nitrate solution is concentrated
in an evaporator or concentrator heated to drive off water, A melt is
produced containing from 95 to 99.8 percent atrir.onium nitrite ar
approximately 422K (3DOCF). This melt is then used to make solid amrooniuru
nitrate products.
Of the various processes used to produce solid ammonium nitrate,
prilling and granulation are the most common. To produce prills, concen-
trated melt is sprayed into the top of a prill tower. Ammonium nitrate
droplets form in the tower and fall countercurrent to a rising air stream
that cools and solidifies the falling droplets into spherical prills.
Prill density can be varied by using different concentrations .^f ammonium
nitrate melt. Low density prills are formed from a 95 to 97.5 percent
ammonium nitrate melt, and high density prills are farmed from a ^9.5 to
99.8 percent melt. High density prills are less porous than low density
prills.
In the prilling process, an additive may be injected into the melt
s'.ream. This additive serves three purposes, to raise the crystalline
transition temperature of the solid final product; to act as a dcsiccant,
drawing water into the final product prills to reduce caking; and to allow
prilling to be conducted at a lower temperature by reducing the freezing
point of molten ammonium nitrate. Magnesium nitrate or magnesium oxide are
examples of additives to the melt streaia. Such additives account for 1 to
2.5 weight percent of the fin^l product. While these additives are
effective replacements for conventional coating materials, their use is not
widespread in the industry.
Rotary drum granulators produce granules by spraying a concentrated
ammonium nitrate melt (99.0 to 99.8 percent) onto small seed particles in a
long rotating cylindrical drum. As the seed particles rotate in the drum,
successive layers of ammonium nitrate are added to the particles, forming
granules. Granules are removed from the granulator and screened. Offsize
granules are crushed and recycled to the granulator to supply additional
seed particles or are dissolved and returned to the solution process. Pan
granulators operate or. ;he same principle as drum granulators and produce i
solid product with physical characteristics similar to those of drum
granules, except the solids are formed in a large, rotating Circular pan.
The temperature of the ammonium nitrate product exiting the solids
formation process is approximately 339 - 397K (150 - 255°F). Rotary drum
or fluidized bed cooling prevents deteric rat ion and agglomeration of soliris
before storage and shipping. Low density piills, which have a high mois-
ture content because of a lower melt concentration, require drying before
ccoling, usually in rotary 'Irums or fluidized beds.
Since the solids are produced in a wide variety of sizes, they must be
screened for consistently sized prills or granules. Cooled prills are
screened, and offsize prills are dissolved and recycled to the solution
concentration process. Granules arc screened before ccoling, undersize
6-8-2 EMISSION FACTORS 1/8-.
-------
particles are returned direct!/ to the granulator, and oversizt! granules
may be either crushed and returned to the granulator or sent to the
solution concentration process.
Following screening, products can be coated in a rotary drum to
privet agglomeration during storage and shipment. The nose common coating
materials are clays and diatomaccous earth. Howevet , the use of .-additives
i.i t.he ammonium nitrale melt before prilling may preclude the use of
coatings.
Solid ammonium nitrate is stored and shipped in either bul< or bags.
Approximately 10 percent of solid ammonium nitrate produced in the United
Stales is b
6.8.2 Emissions and Controls
Emissions fron ammonium r.itratc production plants are particulate
matter (ammonium nitrate and coating materials), amracnia and nitric acid.
Arjtoniii and nitric acid are emitted primarily from solution formation and
concentration processes, with ammonia also being emitted from prili towers
and granulators. rarMculate matter (largely as ammonium nitrate) is
emitted from most of the process operations and is the primary emission
addiessed her-..-.
The emission sources in solution formation and concentration processes
are neutralizers and evaporators, primarily emittiag nitric acid and
ammonia. Specific plant operating characteristics, however, make these
emissions vary depending upon use of e/cess ammonia or acid in the
neutralizes Sir.ce the neutralization operation can dicr.nte the quantity
of these emissions, a range of emission factors is presented in
Table 6.8-1. Parti culate emissions from these operations tend to be
smaller in size than those froir, solids production and handling processes
and generally are recycled back to the process.
Emissions from solids formation processes are ammonium nitrate
particulate matter and ammonia. Tho sources of primary importance are
prill tcwer? (for high density and low density prills) and granulators
(rotary drum and pan). Emissions from prill towers result from carryover
of fine particles and fume by the prill cooling air flowing through the
tower. These fine particles are fr^-m raicroptill formation, attrition of
prills colliding v;ith the tower or one another, and from rapid transition
of the ammonium nitrate between cryttal states. The uncontrolled parti-
culate emissions fron /rill towers, therefore, are affected by tower
airflow, spray melt ter.;peratur «. , condition and type of melt spray device,
air temperature, and f-r/stal stace changes of the solid prills. The amount
of microprill mass that ran be entrained in the prill tower exhaust is
detei'tnii.cd by the tower air vrlocity. Increasing spray melt temperature
causes an inc sase in the amount of gas phase ammonium nitrate generated.
Thus, gaseous emissions from high density prilling are greater than from
low density towers. Microprill formation resulting from partially plugged
orifices of melt spray devices can ircrease fine dust loading and
emissions. Certain designs (spinning buckets) and practices (vibration of
spray plates) help reduce mirroprill formation. High ambient air
temperatures can cause increased emissions because of entrainment as a
Food and Agricultural ]ndust7-y 6.8-3
-------
00
I
TABLE 6.8-1.
EMISSION FACTORS FOR PROCESSES IN i-.MMONIUM NITRATE MANUFACTURING PLANTS
kg/Mg (Ib/ton)
171
JC
tr
'J-.
rartltulate Matter
Process Unront rolled Controlled
Neutrallier
Evaporation /concent ration Ope ratlins
Solids Formation Operations
•itKh denHity prill tnwerb
l3« density prijl tov«re
RL-tnry drita gramilfltorE
Cooleig and UryerB
High density prill coolers
Low dhuRlty prill cmjlern
Low density prill dryere
Kotsry drum grsnulslni coolers
Fan granulalor coolers
Coating Oppratlons
Bulk Loariiru; Operations
*riTlor« are e/ke (ki/ME) and ll/tn.i ,»t
0.045 - 4.3
(0.09 - 8.6)
0.26 (0.5:)
1.59 (3.18)
0.46 (0.92)
146 (292)
0.8 (1.6)
25.8 (51.6)
57.2 CU4.4)
6.1 (16.7)
18.1 O6.6)
0.0 (£)
. Dash • no data.
Rased on tile following crjntrcl tt ficlennles (or wpr Bcruhbers, applied to unconlroll'd falHlone: neutral liers. 95X; nigh den»try prill rower«.
fi/Z; low density prill toward, 4)Z; lotary drua KranaleCore, 99.91; pan granulatorn, W.Stj coolrra, ilryprs and micro, 941.
Glien as mr.^es hpr.au sir nf vailnilon tn data and plant opemtlons. FrctOTB for control led ««lpslons not presented due ro cnnlllctln*. «-esuJrs
on control efficiency.
<4
Based mi 9S1 recover- In a grnnulalor cvcycle ecrubber.
Factors for conlpr« reprpgrnt rrnifclncd prprnolrr and rooter nrelsalnns, and Factora for dryera rppreflenr rnmMn*>H prorltypr and dryer pniaBlonn.
FugltJL : pirtirulate eailsBlons Brine from coating and hulk loading operations.
OD
4---
-------
result of the higher air flow required to ccol prills and because of
increased fume formation at the higher temperatures.
The granulation process in general provides a larger degree of control
In product formation than does prilling. Granulation produces a solid
ammonium nitrate product that, relative to prills, is larger and has
greater abrasion resistance and crushing srrensth. The air flow in
granulation processes is lower than that in Drilling operations. Granu-
lators, however, cannot produce lov density .unmoniuio nitrate economically
with current technology. The design and operating ^ar*.mjters of granula-
tors may affect emission rates. For example, the recycle rate of seed
ammonium nitrate particles affects tbi bed temperature In the granulator.
An increase in bed temperature resulting from decreased recycle of seed
particles may C.-'.USP an increase in dust emissions from granule
disintegration.
Cooling and drying are usually conducted in rotary drums. As with
granulators, the design and operating parameters ot the rotary drums may
affect the quantity of emissions. In addition to design parameters, prill
and granule temperatrre control is necessary to control emissions from
disintegration of solids caused by changes in crystal state.
Emissions from screening operations are generated by the attrition of
the ammonium nitrate solids against the screens and against one another.
Almost all screening operations used in the ammonium nitrate manufacturing
industry are enclosed or have a cover over the uppermost screen. Screening
equipment is located in&lde a building, and emissions are ducted from the
process for recovery or reuse.
Prills and granules a..c typically coated in a rotary dium. The
rotating action produces a uniformly coated product. The mixing action
also causes sone of the coating material to be suspended, creating particu-
late emissions. Rotary drur.iS used to coat solid product are typically kept
at a slight negative pressure, and emissions are vented to a perticulate
control device. Any dust captured is '.isually recycled to the coating
storage 1- -'.ns.
Bagging and bulk loading operations are a source of particulate
emissions. Dust is emitted from each type of bagging process during final
filling when dust laden air is displaced from the bag by the ammonium
nitrate. The potential for emissions during bagging is greater for coated
than for ui.:oated material. It is expected that emissions from bagging
operations are primarily the kaolin, talc or dlatomaceous earth coating
natter. About 90 percent of solid ammonium nitrate procured dorcestically
is bulk loaded. While particulate emissions from bulk loading are not
generally controlled, visible emissions are within typical state regulatory
requirement? (below 20 percent opacity).
Table 6.8-1 summarizes emission factors Cor various processes involved
in th2 manufacture of ammonium nitrate. Unc-jr trolled emissions of particu-
lale matter, ammonia and nitric acid are gi v'en in the Table. Emissions of
ammcnia and nitric acid depend upon specific operating practice", so ranges
of iaoturii ere ^iven for some emission sources.
Food and Agricultural Industry
-------
Emission factors for controlled particulate emissions are also in
Table 6.3-1, reflecting wet scrubbing particular control techniques. The
particle size distribution data presented in Table 6.8-2 indicate trie
applicability of vet scrubbing to control ammonium nitrate particulate
emissions. In addition, wet scrubbing is used as a control technique
because the solution containing the re<-ivered ammonium nitrate can be sent
to the solution concentration process for reuae in production of Ammonium
nitrate, rather thin to weste disposal facilities.
TABLE 6.8-2.
PARTICLE SIZE DISTRIBUTION DATA FOR UNCONTROLLED EMISSION'S
FROM AMMONIUM NITRATE MANUFACTURING /ACILFTIES-
CUMULATIVE UEIGHT Z
< 2.5 urn < 5 un < 10 ura
Solid* Formatio- Operations
Low dencity prill tower
Rotary drun granulator
Coolera and Dryers
Low deneicy prill cooler
Low density prill predryer
Low density prill dryer
Rotary drum granulator cooler
Pan granulator precoc/.ler
5b
0.07
0.03
0.03
0.04
0.06
0.3
73
0.3
0.09
0.06
0.04
0.5
0.3
63
2
0.4
0.2
0.15
3
1 5
^References 4, 11-12, 22-23. Particle size determinations were not done In
•trlct accordacct vlch EPA Method 5. A modification was used to handle the
high concentrations of soluble nitrogenous compounds (See Reference 1).
Particle size distributions were not determined for controlled particulate
References for Section 6.8
1 . Ammonium Nitrate Manufacturing Industry - Technical Document,
EPA-450/3 -81-002, U. S. Environmental Protection Agency, Research
Triangle Park, KG, January 1981.
2. W. J. Search and R. B. Rcznik, Source Assessment; Ammonium Njtrate
Production. EPA-600/2-77-1071, I). S. Environmental Protection Agency,
Research Triangle Park, NC. September 19/7.
3. Memo from C. D. Anderson, Radian Corporation, Durham, NC, to Ammonium
Nitrate file, July 2, 1980.
4. D. P. Be ova r, et al. , Ammonium Nitrate Emission Test Report: Union
Oil Coopany of~California, 5MB-76-NHF-7 , U. S. Environmental
Protection Agency, Research Triangle Park, NC, October 1979.
5. K. P. Brockman, EmiSbion Tests for Particulates, Cominco American.
Beatrice, NE, 197.4.
6. Written communication from S. V. Capone, GCA Corporation, Chapel Hill,
NC, to E. A. Noble, U. S. Environmental Protection Agency, Research
Triangle Park, NC , September 6, 1979.
6.8-6
EMISSION FACTORS
1/84
-------
7. Written communication from D. E. Cayard, Monsanto Agricultural
Products Company, St. Louis, MO, to E. A. Noble, U. S. Environmental
Protection Agency, Research Triangle Park, NC, December 4, 19/fi.
8. Written communication from D. F.. Cayard, Monsanto Agricultural
Products Company, St. Louis, MO, to L'. A, Noble, I!. S. Environmental
Protection Agency, Research Triangle Park, NC, December 27, 1978.
9. Written communication i"rom T. H. Dav.nport, Hercules Incorporated,
Donora, PA, to L'. R. Goodwin, J, S. Fnv irunmeutr. 1 Protection Agency,
Research Triangle Park, NC, November lt>, :978.
10. R. N. Doster and D. J. Grove, Source Sampling Hepcrt: Atlas Powdejr
Company, Entropy Environmentalists, Inc., Research Titangle Park, NC,
August 1976.
11. K. D. Hansen, et al. , Ammonium Nitrate L.'issiun Test Report: .Swift
Chemical Company, EMB-79-XHF-11, U. S. Environmental Protection
Agency. Research Triangle Park, NC, July 1980.
12. R. A. Kniskern, ei a;. , Ammonium Nitrate Emission Test Report;
Cou'trTC- American, Inc. , Beatrice, Nebraska, EMB-79-NHF-9,
U. 5. Environmental Protection Agency, Research Triangle Park, NC,
April 1979.
13. Written coiomunication from J. A. Lawrence, C. F. Industries, Long
Grove, IL, to D. R. Goodwin, 'J. S. Environmental Protection Agency,
Research Triangle Park, NC, December 13, 1978,
14. Written co jnunic:atior. from F. I). McCauley, Hercules Incorporated,
Louisiana, MO, .10 D. R. Goodwin, U. 5. Environmental Protection
A£ency, Research Triangle Park, October 31, 1978.
15. W, E. Misa, Report of Source Test: Collier Carbon and Chemical
Corporation (r^ion Oil), Test No. 5Z-78-3, Anaheim, C/»,
January 12, lV/8.
16. Written communication from L. Musgrove, Georgia Department of Natural
Resources, Atlanta, GA, to R. Rdder, Radian Corporation, Durham, NC,
May 21, 1980.
17. Written communication from D. J. Patterson, N-ReN Corporation,
Cincinnati, OH, to E. A. Noble, U. 5. Environmental Protection Agency,
Research Triangle Park, NC, March 26, 1979.
In. Written '-ommu.iicatlon from H. Schuyten, Chevron Chemical Company, "an
Francisco, CA, to !). R. Goodwin, 1.1. S. Environmental Protection Agenr;.',
March 2, 1979.
19. Emission Test Report: Phillips Chemical Conpany, Texas Air Control
Board, Austin, TX, 197~5.
2r. Surveillance Report: llawkeye ChemicaJ Company, U. 5. l^ivironmental
Protection Agency, K^Ktarch Triangle 1'ark, NC, December 29, 1976.
l/H-'i VOCH! and Agricultural !i;cli:strv 6.8-7
-------
21. W, A. Wade and R. W. Case, Ammonium NitrateEmission lest Report!
C. F. Industries. EMB-79-NHF-1Q, U. S. Environmental Protection
Agency, Research Triangle Park, KC, November 1979.
22, W, A., Wade, et al., Anaonlumi_ ,M_trace Emission Test Report; Coluabia
N1trogen Corporation, EMB-80-NHF-16, U. S. Environmental Protection
Agency, Research Triangle Pa
-------
6.9 ORCHARD HEATERS
6.9.1 General'-*
Orchard healers are commonly used in various areas of the United States to pievent frost damage to fruit and
fruil trees. The five common types of orchard heaters-pipeline, lazy flame, return slack, cone, and solid Fuel-are
shown in Figure 6.9-1. The pipeline heater system is operated from a central control and fuel is diMribu'ed hy .1
piping system from a centrally located lank. Lazy flame, return slack, and cone heaters contain integral tue)
reservoir,, but can be convened to a pipeline system. Solid fuel heaters usually consist only of solid briquettes,
which are placed on the ground and ignited.
The ambient temperature at which orchard heaters are required is determined primarily by the type of fruit
and stage of maturity, by the daytime temperatures, and by the moisture content of the soil and air.
During a heavy thermal inversion, both conveciive and radiant heating methods are useful in preventing frost
damage; there is little difference in the effectiveness of the various heaters. The temperature response for a given
fuel rate is about the same for each type of heater as long as the heater is clean and does not leak. When fiere is
little or no thermal inversion, radiant heal provideJ by pipeline, return stack, or cone heaters is the most effective
method for preventing damage.
Proper location oi the heaters is essential to the uniformity of the radiant heat distributed among the trees.
Heaters are usually located in the center space between four trees and are staggered from one low tu •IIP next.
Extra heaters arc used on the borders of the orchard.
6.9.2 Emissions1'6
Emissio:.s from orchard heaters arc dependent on the fuel usage rate and the type of heater. Pipeline heaters
have the lowest par .cuiate emission rales of all orchard heaters. Hydrocarbon emissions are negligible in the
pipeline heaters ?n.i in lazy flame, return stack, and cone heaters that have been converted to n pipeline system.
Nearly all >>f (he hydrocarKon losses are evaporative losses from fuel contained in the heater reservoir. Because of
ihe low burning ':emneratures ussd, nitrogen oxide emissions are negligible.
Emission factors for the cliff: .ent types of orchard heaters are presented in Table 6 9-1 and Figure 6.9-2.
4/73 Food and Agricultural Indu ,'ry 6.9-1
-------
PIP1UNE HEATER
IAZY FIAIIE
CONE STACK
RETURN STACK
SOLID FUEL
Figure 6.9-1, Types of orchard heaters,6
6.9-2
EMISSION FACTORS
4/73
-------
M
1ft
5
a
>
Iff
3.0
4.0
6.0
9.0
7.0 g.O
FUEL USAGE RATE, Ib, hu-ht
Figure 6.0-2. Paniculate emssic. ~ [rom orchard heaterp.3.6
10.0
11.0
-------
TaMe 6.9-1. EMISSION FACTORS F03 ORCHARD HEATERS*
EMISSION FACTOR RATING: C
Pollutant
Part icu late
Ib/htr-hr
kg/ntr-hr
Sulfur oxide»c
ib/htr-hr
kg/htr-hr
Carbon monoxide
Ib/hti-hr
kg/htr hr
Hydrocarbons'
Ib/htr-yr
kg/htr-yr
Nitrogen oxideih
Ib/htr-hr
kg/htr-hr
Type of heater
Pipeline
Lazy
(lame
b ; b
b
0.1 3Sd
0.06S
6.2
2.8
Neg9
Neg
Neg
Neg
b
o.rs
0.05S
NA
NA
16.0
7.3
Neg
Neg
Return
stack
b
b
0.14S
0.06S
NA
NA
16.0
7.3
Neg
Neg
Core
b
b
O.HS
o.otjs
NA
NA
16.0
7.3
Neg
Neg
Solid
fuel
0.05
0.023
NA«
NA
NA
NA
Neg
Neg
N.jg
Neg
3 References 1.3,4, and 6.
Pgrtlculat* emitfiom for pipeline, lazy fla.'te. return stack, and cone hedteit are
Show, in Figure 6.9-2,
cbned On ernisslon factors for fuel oil conbusiion in Sfction 1.3.
S •> lulfur content.
'Not available
Refersnee 1 Evapcrat ve loiWi on'y- Hyorocarbon «.-iission» from combustion
are considereJ negligible. Ev«por.it;ve hydrocarbon losier for units that are
run ol a pipeline system are negligible.
hLittU iiirogen oxide is formed because of '.he relatively low combust>cn
temperatures
References for Section 6.9
I. Air Pollution in Ventura County, County of Ventura Health Department, Santa Paula, CA, June 1966.
2. Frost Piotecticn in Citrus. Agricultural Extension Service. University of California, Ventura,CA, November
1967.
3. Personal communicaiion with Mr. Wesley Snowden. Valentine. Fisher. «nd Tomlinson, Consulting Engineers,
Seattle, WA, May 1971.
4. Communication with the Smith Energy Company, Los Angeles. CA, January !96S.
5. Communicaiion with Agricultural Extension Service, University of California, Ventura, CA. October 1969,
6. Personal communication wilh Mr. Ted Wakai. -Mr Pollution Corirol District. County of Ventura. Ojai.CA,
May 1472
6.9-4
EMISSION FACTORS
7/79
-------
6.10 PHOSPHATE FERTILIZERS
6.10.1 NORMAL SUPERPHOSPHATES1
6.10.1.1 General
The term "normal superphosphate" is used to designate u fertilizer
material containing IS - 21 percent P2®5- I1 ls prepared by reacting
ground phosphate rock with 65 - 75 percent sulfuric acid. Rock and acid
arc mixed In a reaction vessel, held In an erclosed area (den) while the
reaction mixture solidifies, end transferred to a storage pile for
curing. Following curing, the product is most often ground and bagged
for sale as run-of-the-pile product. It can also be granulated, for
sale as granulated superphosphate or granular mixed fertilizer. However,
this accounts for less than 5 percent of tota.L production. To produce a
granular normal superphosphate material., run-uf-th«-pile material is
first fed to a pulverizer Un be crushed, ground, and screened. Screened
material is sent to a rotary drum granuletor und then through a rotary
dryer. The material goes through a rotary coder and on to storage bins
for sale as bagged or bulk product. Superphosphate fertilizers are
produced at 79 plants in the United States. A generalized flow diagram
of the process for the production of normal superphosphate is shown in
Figure 6.10.1-1.
6.10.1.2 Emissions anH Controls
Sources of emissions at n normal superphosphate plant include rock
unloading and feeding, mixer (reactor), den, curing building, and fertil-
izer handling operations. Rock unloading, handling and feeding generate
particular, emissions of phosphate rock Just. The mixer, den and
curing building emit gaseoi-s fluorides (HF and SlFi*) and partlculates
COiiit c/aed of fluoride and phosphate material. Fertilizer handling oper-
a^ions release fertiliser dust.
At a typical normal superphosphate plant, the rock unloading,
handling and feeding operations are controlled by a baghouse. The mixer
and den are controlled by a wet scrubber. The. curing building and
fertilizer hand litg operations normally are not controlled.
Emission factors for the production of normal superphosphate are
presented in Table 6.10.1-1. Thes». emifi.sicn factors are rvcragfis based
on recent source test data from controlled phosphate fertilizer plants
in Florida.
10/80 Fooo and Agricultural Industry 6.10.1-1
-------
IACHOU&C
ROCK
UNLOADING
PHObPHAU HOCK
_L
i ^i
ROCK UN
PMIICU*lf
ROCK F((D»
(MISSION!.
4
..JHSL^T4-)^
MIGHH y^
ROCK UN
'1
suniKic-
ACID
DCN
TOCVPKW
~ 1
ID
TWX.
1
.r
JPO
UM_
J
6
^CO*
/COW
n MUM
I
-------
TABLE 6.10.1-1. EMISSION FACTORS FOR THE PRODUCTION OF
NORMAL SUPERPHOSPHATE3
EMISSION FACTOR RATING: A
Emission point
Rock unloading
ROV.K feeding
Mixer and denc
Curing building
Pollutant
Particulate
Particulate
Particulate
Fluoride
Paniculate
Fluoride
Emission
Ib/eon P 0
0.56
0.11
0.52
0.20
7.20
3.80
factor
kg/MT P205
0.2S
0.06
0.26
0.10
3.60
1.90
^Reference 1, pp. 74-77, 169.
Factors are for emissions from baghouse with an estimated collection
efficiency of 99%.
Factors are for emissions from wet scrubbers with a reported 97%
.control efficiency.
Uncontrolled.
Particulate omissions from ground rock unloading, storage and
transfer systems are controlled by baghouse collectors. These cloth
filters have reported efficiencies of over 99 percent. Collected solids
are recycled to the process.
Silicon tecrafluoride and hydrogen fluoride emissions, and partic-
ulate from the mixer, den and curing building are controlled by scrubbing
the offgases with recycled water. Gaseous silicon tutrafluoride in the
presence of moisture reacts to form gelatinous silica which has the
tendency to plug scru'r.jer packings. The use of conventional packed
counternurrent scrubbers and other contacting devices with small gas
passages fcr emissions control is therefore limited. Scrubber types
that can be used are cyclonic, venturi. impingement, jet ejector and
spray crcasflow packed. Spray towers also find use as precontactors for
fluorine removal at relatively high concentration levels (greater t'vin
3,000 ppn, or 4.67 g,/n^).
Air pollution :cntrol techniques vary with particular plant designs.
The effectiveness of abatement systems in removal of fluoride %nd
particular.? also vs.ties from plant to plant, depending on a number o;
factors. The effectiveness of fluorine abatement is determined by (L)
inlet fluorine concentration, (2) outlet or saturated gas temperature,
(3) composition and temprature of the scrubbing liquid, (4) scrubber
and transfer units, and (5) effcctiveno-jg of entrainment separation.
.i'ol efficiency is enhanced by increasing the number of scrubbing
10/80 Food anJ Agricultural Industry 6.10.1-3
-------
stages in series and by using a fresh water scrub in the final stage.
Reported efficiencies for fluoride control range from less than 90
percent co over 99 percent, depending on inlet fluoride concentrations
and the, system employed. An efficiency of 98 percent for participate
control is achievable.
Reference for Section 5.10.1
1. J. M. Nyers, et al.. Soui^e Assessment: Phosphate Fertilizer
Industry. EPA-600/2-79-019c, U. S. Environmental Protection Agency,
Research Triangle Park, NC, May 1979.
6.10.1-4
EMISSION FACTORS
10/80
-------
6.10.2 TRIPLE SUPERPHOSPHATES
6.10.2.1 General1
Triple superphosphate is a fertilizer material of ?2^S content over
40 percent, made by reacting phosphate ruck and phosphoric acid. The
two principal types of triple superphosphate are run-of-tht'-pile (40
percent of total production) and granular (60 percent of tctal produc-
tion). Run-of-the-pile material is essentially a pulverized mass of
variable particle size produced in a manner similar to normal super-
phosphate. Thus, phosphoric acid (50 percent ^2^5^ *-s reacted in a cone
mixer with ground phosphate rock. The resultant slurry begins to
sciidify on a slow moving conveyer (den) en rout,2 to the curing area.
AL the point of discharge from the den, the material passes through a
rotary mechanical cutter that breaks up the solid mass. Coarse run-of-
tl.c-pile product is sent to a storage pile and cured for a period of 3
to 5 weeks. The final product is then rained from the "pile" in the
curing shed, and then crushed, screened, n"d shipped in bulk. Granular
triple superphosphate yields larger, more uniform particles with Improved
storage and handling properties. Most of this material is made with the
Dorr-Oliver slurry granulation process, illustrated in Figure 6.10.2-1.
In this process, ground phosphate rock is mixed with phosphoric acid in
a reactor or mixing tank. The phosphoric acid used in this process is
appreciably lower in concentration (40 percent P205) than that used to
manufacture run-of-the-pile product, because the lower strength acid
maintains the slurry in & fluid state during a mixing period of 1 to 2
hours. A thin slurry is continuously removed and distributed onto
dried, recycled fines, where it coats the granule surfaces and builds up
its size.
Pugmills and rotating drum granulators are used in the granulation
process. A pugmill is composed of a u-shaped trough carrying twin
contrarotating shafts, upon which are mounted st-'ong blades or paddles.
Their action agitates, shears and knead? the solid/liquid mix and trans-
ports the material along the trough. The basic rotary drum granulator
consists of an open ended slightly inclined rotary cylinder, with retain-
ing rings at each end and a scraper or cutter mounted inside the drum
shell. A rclling bed of dry material is maintained in the unit while
the slurry is introduced through distributor pipes set lengthwise in the
drum under the bed. Slurry-wetted granules then discharge onto a
rotary dryer, where excess water :_s evaporated and the chemical reaction
is accelerated to completion by the dryer heat. Dried granules arc then
sized on vibrating screens. Oversize particles are crushed and recircu-
lated to the screen, and undersize particles are recycled to the granu-
lator. Product size granules are cooled in a countercurrent rotary
drum, then sent to a storage pile for curing. After a curing period cf
3 to 5 days, granule:? are removed from storage, screened, bagged and
shipped.
in/L)r) Food and Agricultural Industry 6.10.2-1
-------
c
I
in
V.
"uiicuun
I MB HUOIIM
oaiie KJIIOIIC
Figure 6.10.2-1. Dorr-Oliver process flow diagram for
granular triple superphosphate prodjetIon.
CJ
o
-------
6.10.2.2 Emissions and Controls
Emissions of fluorine compounds and dust particles occui during the
production of granular triple superphosphate. Silicon tetrafluoride and
hydrogen fluoride are released by the acidulation reaction and they
evolve from the reactors, den, granulator, dryer and cooler. Evolution
of fluorides continues at a lower rate in the curing b'lilding, as the
reaction preceeds. Sources of particulate emissions include the reactor,
granulator, dryer, cooler, screens, mills, and transfer conveyors.
Additional emissions of participate result from the unloading, storage
and transfer of ground phosphate rock.
At a typical plant, emissions from the reactor, den and granuiator
are controlled by scrubbing the effluent pas with recycled gypsum pond
water. Emissions from the diyer, cooler, screens, milIf, product trans-
fer systems, and storage building ar^ sent to a cyclone separator for
removal of a portion of the dust before going to wet scrubbers. Bag-
houses are used to control the fine rock particles generated by the
preliminary ground rock handling activities.
Emission factors fur the production of run-of-the-pile and granular
triple superphosphate are given in Table 6.10.2-1. These emission
factors are averages based on recent source test data from controlled
phosphate fertilizer plants in Florida.
Particulate emissions from ground rock unloading, storage and
transfer systems are controlled by baghouse collectors. These cloth
filters have reported efficiencies of over 99 percent. Collected solids
are recycled to the process. Emissions of silicon tetrafluoride, hydrogen
fluoride, and particulate from the production area and curing building
are controlled by scrubbing the offgases with recycled water. Exhausts
from the dryer, cooler, screens, mills, and curing building are sent
first to a cyclone separator and then to a wet scrubber.
Gaseous silicon tetrafluoride in the presence of moisture reactf to
form gelatinous silica, which has the tendency to plug scrubber packings.
The use of conventional packed countercurrer.r scrubbers and other con-
tacting devices with small gas passages for emissions control .is there-
fore limited. Scrubber types that can be used are (1) spray tower, (2)
cyclonic, (3) venturl, (4) impingement, (5) Jet ejector, and (6) spray-
crossflow packed.
Spray towers are used as precontactors for fluorine removal at
relatively high concentration levels (greater than 3,000 ppm, or 4.67
g/m3).
Air pollution control techniques vary with particular plant designs.
The effectiveness of abatement systems for the removal of fluoride and
particulate also varies from plant to plant, depending on a number of
factors. The effectiveness of fluorine abatement is determined by (1)
10/80 Food and Agricultural Industry 6.10.2-3
-------
i
.c-
TABLE 6-10.2-1. CONTROLLED EMISSION FACTORS FOK THE PRODUCTION OF TRIPLE SUPERPHOSPHATES*
EMISSION FACTOR FATING: A
Controlled emission factor
Process
Run-of-the-pile triple
superphosphate
M
W
in
i-t
§? Granular tripe
>zj superphosphate
0
d
V)
Emission point
Rock unloading
Rock feeding
Cone mixer, den
and curing building
Rock unloading
Rock feeding
Reactor, granulator^
dryer, cooler and
screens
Curing building0
Pollutant
Particuiate
Particulate
Particulate
Fluoride
Particulate
Particulate
Parti: ilate
Fluoride
Particulate
Fluoride
Ib/ton P 0
0.14
0.03
0.03
G.2U
0.18
0.03
0.10
0.24
0.20
0.04
kg/MT P205
0.07
0.01
0.02
0.10
0.09
0.02
0.05
0.12
0.10
0.02
D
o
^Reference 1, pp. 77-80, 168, 170-171,
Factors are for emissions from baghouses with an estimated collection efflciericy of 99Z.
Factors are for emissions from wet scrubbe '3 with an estimated 97% control efficiency.
-------
inlet fluorine concentration, (2) outlet or saturated gas temperature,
(3) composition and temperature of the scrubbing liquid, (4) scrubber
type and transfer units, and (5) effectiveness of entr^lnuient separation.
Control efficiency is enhanced hy increasing the number of scrubbing
stages In series and by using a fresh water scrub in the final stage.
Reported efficiencies for fluoride control range from lews than 90
percent to over 99 percent, depending on inlet fluoride concentrations
arA the sy.steu employed. An efficiency of 98 percent for particulate
control Is achievable.
Reference for Section 6.10.2
1. J. M. Nyers, et al., SourceAssessment; Phosphate Fertilizer
Indus try, EPA-600/2-79-019c, U. S. Environmental Protection Agency,
Research Triangle Park, NC, May 1979.
10/80 Food and Agricultural Industry 6.10.2-5
-------
6.10.3 AMMONIUM PHOSPHATES
6.10.3.1 General1
Ammonium phosphates are produced by reacting phosphoric acid with
anhydrous ammonia. Both solid anJ liquid ammonium phosphate fertilizers
are produced in the United States. Ammonia ted superphosphates arc also
produced, by adding normal superphosphate or triple superphosphate to
the mixture. This discussion rovars only the granulation of phosphoric
acid with anhydrous arrraonia to produce granular fertilizers. The produc-
tion of liquid ammonium phosphates and ammoniated superphosphates in
fertilizer mixing plants is considered a separate process. Two basic
mixer designs are used by ammoniac ion-granulation plants, the pugmill
ammoniator and the rotary drum ammoniator. Approximately 95 percent of
ammoniation-granulation plants in the United States use a rotary drum
mixer developed and patented by the Tennessee Valley Authority (TVA) .
In the TVA process, phosphoric acid is mixed in an acid surge tank with
93 percent sulfuric acid (used for product analysis control) and with
recycle and acid from wet scrubbers (see Figure 6.10.3-1). Mixed acids
are then partially neutralized with liquid or gaseous anhydrous ammonia
in a brick lined acid reactor. All phosphoric acid and approximately 70
percent of ammonia a.-e introduced into t'lis vessel.
A slurry of NHi^HoPO^ and 22 percent. water i& produced and sent
through steam-traced lines to the ?mou:nlat:or -pranulator. Aimonia rich
of {gases from the reactor are wet scrubbed before exhausting to the
atmosphere. Primary scrubbers use r£w material-mixed acids as scrubbing
liquor, and secondary scrubbers use gypsum pond water.
The basic rotary drum antmoniator-granulator consists of a slightly
inclined open end rotary cylinder with retaining rings at each end, and
a scraper or cutter mounted inside the drum shel1 . A rolling b^d of
"-••Vied solids is maintained in the units. Slurry from the reactor is
distributed on the bed, and the remaining ammonia (approximately 30
percent) Is sparged underneath. Granulation, by agglomeration anJ by
coating particules with slurry, takes plarn in the rotating drum and is
completed in the dryer. Ammonia rich offgases pass '.hrough a wet
scrubber before exhausting to the atmosphere.
Moist ammonium phosphate granules are transferred to a rotary
cccurrent dryer and then to a cooler. Before exhf.utting to the atmo-
i"here, these off gases pass through cyclones and wet scrubbers. Cooled
granules pass to a double deck screen, in which oversize and undersize
particles are separated from product particles.
6.10.3.2 Emissions and Controls
Air emissions from production of anrnonium phosphate fertilizers by
aramrniation granulation of phosphoric acid and amnonia result from five
process operations. The reactor and airjwvilator granulatur produce
10/80 Food and Agricultural Industry 6.10.3-1
-------
U)
in
i—i
O
nonn m jmw.
WCCIMC Offluu iwi
Figure 6.2.3-1. Ammonium phosphate process flow diagram.
CJ
o
-------
emissions of gaseous ammonia, gaseous fluorides (HF and SiF4) and partic-
ulate cmmonium phosphates. These two exhaust streams generally are
combined and passe.' through primary and secondary scrubbers.
Exhaust gases from the dryer and cooler also contain amnonia,
fluorides and participates, and these streams commonly are combined and
passed through cyclones and primary and secondary scrubbers. Partlc-
ulate emissions and low levels of ammonia and fluorides from product
sizing and material transfer operations are controlled the sam<2 way.
Emission factors for ammorium phosphate production are summarized
in Table 6.10.3-1. These emission factors are averages based on recent
source test data from controlled phosphate fertilizer plants in Florida.
Exhaust streams from the reactor and atnnoniator-granulator pass
through a primary scrubber, in which phosphoric acid recovers ammonia
and particulate. Exhaust gases from the dryer, cooler and screen go
first to cyclones for particulate recovery, and from there to primary
scrubbers. Materials collected in the cyclone and primary scrubbers are
returned to the process. The exhaust is sent to secondary scrubbers,
where recycled gypsum pond water is used as a scrubbing liquid to control
fluoride emls^icus. The scrubber effluent Is returned to the gypsum
pond.
Primary scrubbing equipment commonly includes venturi and cyclonic
spray towers, while cyclonic spray towers, impingement scrubbers, and
spray-crossflow packed bed scrubbers are used as secondary controls.
Primary scrubbers generally use phosphoric acid of 20 to 30 percent as
scrubbing liquor, principally to recover ammonia. Secondary scrubbers
generally use gypsum and pond water, for fluoride control.
Throughout the industry, however, there are many combinations and
variations. Some plants use reactor-feed concentration phosnnoric acid
(40 percant ^2®$) ^II both primary and secondary scrubbers, and some use
phosphoric acid near the dilute end of the 20 to 30 percent P^s range
in only a single scrubber. Existing plants are equipped with ammonia
recovery scrubbers on the reactor, ammonlator-granulator and dryer, and
particulate controls on _iie dryer and coc'er. Additional scrubbers for
fluoride removal are common but not typical. Only 15 to 20 percent of
installations contacted in an EPA survey were equipped with spr.iy-
crossflow packed bed scrubbers or their equivalent for fluoride removal.
Emission control efficiencies for ammonium plv-sphatr. plcnt control
equipment have been reported as 94 •• 99 percent for ammorlura, 75 - 99.8
percent for particulates, and 74 - 94 percent for fluorides.
10/80 Food and Agricultural Industry 6,10.3-3
-------
TABLE 6.10.3-1. AVERAGE CONTROLLED EMISSION FACTORS FOR THE
PRODUCTION OF AMMONIUM PHOSPHATES*
EMISSION FACTOP RATING: A
Emission Point
Reactor /ammonia to r-granula tor
Fluoride (a- F)
Participates
Ammonia
Dryer/cooler
Fluoride (as F)
Particulates
Ammonia
Product sizing and material transfer
Fluoride (as F)c
Patticulates0
Ammonia
Total plant emissions
Fluoride (as F)d
Particulf. ces
Ammonia
Controlled
Ib/ton P20,
0.05
1.52
b
0.03
1.50
b
0.01
0.06
b
0.08
0.30
0.1/<
Emission Factors
. kg/MT P205
0.02
0.76
b
0.02
0.75
b
0.01
0.03
b
0.04
0.15
0.07
^Reference 1, pp. 80-83, 173.
No Information available. Although ammonia Is emitted from these unit
operations, it is reported as a total plant emission.
.Represents only one sample.
EPA has promulgated a fluoride emission guideline of 0.03 g/kg P2^5
input.
Based on limited data from only 2 plants.
Reference for Section 6.10.3
1. J. M. Nyers, et al. , Souice Assessment: Puosj)hai:e Fertilizer
Industry, EPA-600/2-79-019c, U.S. Environmental Protection Agency,
Research Triangle Park, NC, May 1979.
6.10.3-4 EMISSION FACTORS 10/80
-------
6.11 STARCH MANUFACTURING
6.11.1 Process Description'
The basic raw rratenal in the manufacture of starch is den', corn, which contains starch. The st<«ch in the
corn is separated from the other components by "wet milling."
The shelled grain is prepared lor milling in cleaners (hat remove both the light chaff and any heavte, foreign
material. The cleaned corn is Ihen softened by soaking (s'eeping) it in warm water acidified wit'1, sulfur dioxide.
The softened corn goes through attrition mills that tear the kernels apart, freeing the germ und loosening the hull.
The remaining mixture of starch, gluten, and hulls is finely ground, and the coarser fiber particles arc removed by
screening. The mixture uf;!->rch and gluten is then separated by centrifuges, after which ths starch is filtered and
washed. At this point it is dried und packaged for market.
6.11.2 Emissions
The manufacture of starch from co'i can result in significant dust emissions. The various cleaning, gnnun 0,
and screening operations are the major sources of dust emissions. Table 6.11-1 presents emission factors for starch
manufacturing.
Tafafe 6.11-1. EMISSION FACTORS
FOR STARCH MANUFACTURING*
EMISSION FACTOR RATING: 0
Type of opera'-on
Uncontrolled
Controlled1"
Participates
Ib/ton
8
0.02
kg/MT
4
0.01
'Rafeiance 2.
t>Hij»d on centrif jgil gtt tcruhbtr.
References for Section 6.1 1
1. Starch Manufacturing In: Kirk-Otluner Encyclopedia of Chemical Technology, Vol. IX. New York, John
Wiley and Sons, Inc. 1°64
2. Storch, H. L. Product Losses Cut with a Centrifugal GasSciubber. Chem. Eng. Progi. 62.51-54 April
2/72 Food and Agricultural Industry 6.1 1-1
-------
6.12 SUGAR CAME PROCESSING
6.12.1 General l3
Sugar cane is burned in the Held prior to harvesting to remove unwarned foliage as well as to control rodents
and insects. Harvesting is done by hand or, where possible, by mechanical means.
After harvesting, the care goes through a series of processing steps Tor conversion to (he fm&l sugar product. It
is first washed to remove dirt and Iraslr. then crushed and shredded to >educe the sir" of the stalks. The juice is
next extracted by one of two method!!, milling 3
The largest sources of emissions from sugar cane processing are the openfield burning in the harvesting of the
crop and (he burning if bagasse as fuel. In the various processes of cresting, evaporation, and crystallization,
relatively small quantities of participates are emitted. Emission factors for sugar cane field burning are shown in
Table 2.4-2. Emission factors for haea&se firing in boilers aie included in Chapter 1 >
References for Section 6.12
1. Sugar Cane. In: Kirk-Othmer Enc; "lopedla of Chemical Technology, Vol. IX. New Yoik, John Wiley and
Sons, Inc. 1964.
2. Darley, E. F. Air Pollution Emissions from Burning Sugar Cane and Pineapple from Hawaii. In Air Pollution
from Forest and Agricultural Burning. Statewide Air Pollution Research Ceni?i, University uf California,
Riverside, Calif. Prepared fo: Environmental Protection Agency, Research Triangi? Park, NX. under Grant
No R800711 August 1974.
3. Background Information for Establishment of National Standards of Performance for New Sources. Raw Cane
Sugar Industry. Environmental Engineering, Inc. Gainesville, Fla. Prepared for Environmental Protection
Agency, Research Triangle Park, N.C. under Contract No. CPA 70-142, Task Order 9c July IS. 1971.
4/76 Fojd and Agricultural Industry 6.12-1
-------
A,<3 BREAD BAKING
ft.13.1 Central1-2
Banery products generally can be divided into two groups—pioducts leavened by yeast and products
chemiodllv leavened by baking powder. Other than yeast bread, which comprises the largest fraction of
all '.east leavrned baking production, leavrned products include sweet mil.*, crank; rs. pret/.els, etc
K-.arnpIc- of chemically leavened baking products are cakes, cookie*. <-akc doughnut?, cum bread and
iiakmg povxlei biscuits.
Bread is generally produced by either the straighl-dough prtu < -- or (he sponge-dough process. In the
xtraighl-dnugh process, the ingredients arc mixed, allowed to feiinf-nt. and then bpe of yeast.
Laboratory experiments' and ihemetn ^1 estimates2 .suggest that pthannl emissions from the sponge-
dinijjh pincess may range from o to 8 pounds per 1000 pound? of bread produced, whereas ethanol
emissions friun the itruight-dough process ar«' onl> 0.5 piuinds per 1000 pour,ds pruduccd. 1 hesc (actors
include tthanul evapii'ation from all phases of bread production, although must tif the emissions occur
during baking. Negligible e«rry' Trunglr Park. \C Decrmbu !9TB.
2 ^ C . Hrntifr^mi. "(.. Research
Tr.anide Park. NC. Au^us! 197S.
Food and Agricultural Industry 6.13-1
-------
6.14 UREA
6.14.1 General1
Urea (COtNb^la). alsc known as carbamide or carbonyl diamiu.2, is
produced by reacting ammonia and carbon dioxide at >U8 - 473K (347 - 392°F)
and 13.7 - 23.2 MPa (2,0002 - 3,400 psi) to form ammonium carbamate
(NH^COrNM . Pressure may be as high as 41.0 MPa (5,0«"'0 -,si) . ' Ures IK
formed by a dehydration decomposition of ammonium carbamate.
Urea is marketed as a solution or :in a variety of solid forms. Most
urea solution produced is used in f ercilize? mixtures, with a small ai« our.t
going to animal feed supplements. Most solids are produced <.s prills or
granules, for use as fertilizer or protein supplement In animal feeds, and
use in plastics manufacturing. Five U. S. plants produce solid urea in
crystalline form.
The process for manufacturing urea involves a combination of up to
seven major unit operations. These operations, illustrated by the flow
diagram in Figure 6.14-1, are solution synthesis, solution concentration,
solids formation, solids cooling, solid;; screening, solids coating, and
bagging and/or bulk shipping.
AMMONIA*
cmo* _
DIODDI '
MCCINO
I
ULUTIOIS
OFFIinillCICil
tULk
DIMIOMl WITH KQi.lDWl lUIUFtCTUKNG HUt'lCtS
Fipure 6,14-1. Major urea manufacturing operations.
The combination of processing steps is determined by trie desired end
products. For example; planes producing urea solution use only the solution
formulation and bulk shipping operations. Facilities producing solid urea
ai*n».«y thcic cwo operations and vaiiour Combinations of the remaining five
operations, depending upon the specific end proauct heing produced.
In the solution synthesis operation, ammonia and COj are reacted to
form ammonium carbamate. The carbamate ir then dehydrated to yield 70 to
11 percent aqueous urea solution. This solution can be used as an
1/84
Food and Agricultural Induitry
6.14-1
-------
ingredient of nitrogen solution fertilizers, or it can be concentrated
further to produce solid urea.
The concentration process furnishes ure^ melt for solids formation.
The three methods of concentrating the urea solution are vacuum concentra-
tion, crystallization and atmospheric evaporation. The method chosen
depends upon the level of biuret (NH;>CONHCONH2) impurity allowable in the
end product. The most common method of solution concentration is
,vaporatlcn.
I'rea solids are produced from the urea melt by two basic methods,
prilling and granulation. Prilling is a process by which solid particles
are produced from molten urea. Molten urea is sprayed from the top of a
prill tower, and as the droplets fall through a countercurrent air flow,
they cool and solidify into nearly spherical particles. There are two types
of prill towers, fluidized bed and nonfluldized bed. The major difference
between these towers is that a separate solids cooling operation may be
required to produce agricultural grade prills in a nonfluidized bed prill
tower."4
Granulation is more popular tuan prilling in producing solid urea for
fertilizer. There are two granulation methods, drum granulation and pan
granulation. In drum granulation, solids are built up in layers on seed
granules in a rotating drum granulator/cooler approximately 14 feet in
diameter. Pan granulators also form the product in a layering process, but
different equipment is u=jed, and pan granuiators are not common in this
country.
The solids cooling operation generally is accomplished during solids
formation, but for pan granulation processes and for some agricultural grade
prills, some supplementary cooling is provided by auxiliary rotary drums.
The solids sr.reeni.ig operation removes offsize product fron solid urea.
The offsize material may be returned to the process in the solid phase or be
redissolved in water and returned to the solution concentration process.
Clay coatings are used in the urea industry to reduce product caking
and urea dust formation, even though they also reduce the nitrogen content
of the product, and the coating operation creates clay dust emissions. The
popularity of clay coating has diminished considerably because of the
practice of injecting formaldehyde additives into the liquid or molten urea
before solids formation.3"6 AdditJves reduce solids caking during storage
and urea dust formation during transport and handling.
The majorif of solid urea product is bulk shipped in trucks, enclosed
railroad cars, or barges, but approximately 10 percent is bagged.
O.14.2 Emissions and Controls
Emissions fro.2 urea manufacture include ammonia and particulate matter.
Ammonia is emitted during the solution synthesis and solids production
processes. Particulate matter is the primary emission being addressed here.
There have been m' reliable measurements of free gaseous formaldehyde
emissions. The c'romotropic acid procedure that has been used to measure
6.14-2 E:-;TSSION FACTOR-:,
1/84
-------
formaldehyde is not capable of distinguishing between gaseous formaldehyde
and methylenediurea, the principle compound formed when the formaldehyde
additive reacts with hot urea.7"8
In the synthesis process, some emission control Is Inherent in the
recycle process where carbamate gases and/or liquids are recovered and
recycled. Typical emission sources from the solution synthesis process are
noacondensrble vent streams from ammonium carbamate decomposers and
separators. Emissions from synthesis processes are generally combined with
emissions from the solution concentration process and are vented through a
common stack. Conbined partlculate emissions from urea synthesis and
concentration are ,nuch less than particulate emissions from a typical solids
producing urea plant. The synthesis and concentration operations are
usually uncontrolled except for recycle provisions to recover ammonia. For
tl.ese reasons, no factor for controlled emissions from synthesis and
concentration processes Is given in this section.
Uncontrolled emission rates from prill towers may be affected by the
following factors:
- product grade being produced
- air flow rate through the cower
type of tower bed
- ambient temperature and humidity
The cotal of mass emissions per unit is usually lower for feed grade prill
production than for agricultural grade prills, due to lower airflows.'
Uncontrolled particulate emission rates for fluldized bed prill tower? are
higher than those for nonfluidized bed prill towers mnking agricultural
grade prills and are approximately equal to those fcr nonfluidized bed feed
grade prills.1* Ambient air conditions c.in affect prill tower emissions.
Available dita Indicate that colder temperatures promote Che formation of
smaller particles in the prill tower exhaust.9 Since smaller particles are
more difficult to remove, the efficiency of prill tower control devices
tends to decrease with ambient temperatures. This can lead to higher
emission levels for prill towers operated during cold weather. Ambient
humidity can also affect prill tower emissions. Air flow rates must be
Increased with high humidity, and higher air flow rates usually cause higher
emissions.
The design parameters of drum granulators and rotary drum coolers may
affect emissions. 0-11
Urum granulators have an advantage over prill towers In that they are
capable of producing very larg-3 particles without difficulty. Granulators
also require less air for operation than do prill towers. A disadvantage of
granulators is their inability to produce the smaller feed grade granules
economically. To produce smaller granules, the drum must be operated at a
higher seed particle recycle rate. It has been reported that, although the
increase in seed material results in a lower beu temperature, the
corresponding increase in fines in the granulator causes a higher emission
rate.1" Cooling air passing through thn drum granulator entrains
approximately 10 to 20 percent of "-.he product.® This air stream is
1/84 Food and Agricultural Industry 6.14-3
-------
controlled with a wet scrubber which is standard process equipment on drum
granulators.
In the solids screening process, dust is generated by abrasion of urea
particles and the vibration of the screening mechanisms. Therefore, almost
all screening operations used in the urea manufacturing industry are
enclosed or are covered over the uppermost screen. This operation is a
STcall emission source, and particulate emissions from solids screening are
not treated hcre.I2~1;1
Emissions attributable to coating include entrained clay dust frp.ti
loading, inplant transfer, and leaks from the s^als jf the coat source of participate emissions. Dust is
emitted from each bagging eethod during the final stages of filling, when
dustladen air is displaced from the bag by urea. Bagging operations are
conducted inside warehouses and are usually vented to keep dust out of the
workroom area, according to OSHA regulations. Most vents are controlled
with baghouses. Nationwide, approximately 90 percent of urea produced is
bulk loaded. Few plants control their bulk loading operations. Generation
of visible fugitive particles is slight.
Table 6.14-1 summarizes tru> uncontrolled and controlled emission
factors, by processes, for urea manufacture. Table 6.14-2 summarizes
particle sizes for thei>e .missions.
TABLE 6.14-2. UNCONTROLLED PARTICLE Sl/.t. DATA KOK UREA 1'RODUCl ION3
OPE. ATI ON
PARTICLE STZE
(Cunmulatlve Weight Z)
< 10 urn * 5 urn < 2.5 urn
Solution Formation and Concentration
Solids Formation
Nonfluidlzed bed prilling
agricultural grade
f*ed grade
Fluidized !>ed prilling
agricultural grade
feed giadc
Drum granulation
Rotary Drum Cooler
Bagging
Bulk Loading
NA
90
85
60
24
b
c.n
N"/>.
MA
HA
84
74
52
13
b
0.15
NA
NA
NA
79
50
A3
l<4
b
0.04
NA
NA
NA » not available. No data were available on particle sizes of controlled
eoissions. Particle size information was collected uncontrolled in che
ducts and may net reflect particle size in the ambient air.
All particular matter ~> 5.7 urn vae collected In the cyclone prccollectcr
sampling equipment.
6.14-4
EMISSION 1- ACTORS
-------
TABLE 6.14-1. EMISSION FACTORS FOR UREA PRODUCTIONa
EMISSION FACTOR RATING: Ab
Partlculates0
Operation
Solution formation ,
and concentration
Solid! formation
Nonfluldlzid
beu prilling
agricultural gr"'Je*
feed grsdej
Fluldlzed bed prllllag
agricultural glade1'
feed gratis^
L
Drua grunulatlon I
Rotary drum cooler
Uncontrolled
Icg/Mg Ih/ton
0.0105* 0.021*
l.9h 3.8h
l.B 3.6
3.1 6.2
l.B 3.6
JO 3*1
3.72 7.45
0.095° 0.19°
Controlled
|cj7Kg Ib/con
C.032 0.064
NA NA
0.39 0.78
0.24 0.48
0.115 0.234
0..0* 0.20*
NA NA
Atmonia
Uncontrolled Sxlt'.o^ Cootrol Pevlcei
kg/Hg Ib/ton Kl/Mg
9.12f 18.24£
C.43 0.87 1
NA NA NA
1.46 2.91 I
2.07 4.14 1.04
1.071 2.151 h
0.0236 0.05'. NA
NA NA NA
Ib/ton
t
NA
1
2. OB
li
XA
NA
*Based on *nliilons per unlL of production output. Dash • not applicable. NA • not available.
Emission Factor Rjtloj Is C for controlled ^articulate ealaalona {com rotary drun coolers
and uncontrolled partlculate •nlailooi from bagglag.
CFartlculate Eeat data wire collected ualog a modification of EPA Ref trine- Hachod 5. Refmencc 1,
Appendix B explains these oodlflcsciona.
\*fer*oc'it 14 - 16, 19. Cudaslona frcm th« aynthcili procexi ire generally combined vl:h ealialans
{TOO thi solution coocrncratlon prjceaa and vented through a coiman stack. Ir the synthesis
pro:«ee. toot eoliflon control It inherent In t, e recycle proceit where carbaoat* $a»ei and/or
liquids are recovered and recycled.
*K7A lust data Indicated a rarge cc 0.0052 - 0.0150 kg/Kg (0.0104 - 0.0317 Ibftoa).
fEPA teat data Indicated a range of 3.79 - 14.44 kg/Hg (7.58 - 28.89 Ih/ton).
20. Thtei factors were determined at :n «mbl*nt tenperature of 288K - T94K
(i7"F - 69*F). The concroiiad emission factors art baaed on ducting exhaust '.hrnugh a do^ncouer
_,nd then a vetted fiber filter tcrubber achiev.-.,< * 98.3 percsnt efficiency. Thle repnaencs &
higher degree of control than la c;plcni ID this, industry.
Figures an baaed o£ £PA test data. Indue cry teat data ranged trod 0.39 - 1.79 Kg/Kg
(0.78 - J.58 IWton).
No aoaonla control demonstrated hy scrubbers Installed for partlc.ilatt concroJ. 5 one lucrcase in
unnonla eil)Slon§ exiting the control device vas noted,
^Refereacs 19. Feed grade factors uere deteralned at an amslent temvierature of 302K (83'F) and
agricultural grade factors at an aobleut temperature of :5yK (80°F). For fluidlied bed prilling,
controlled enlaaton factors are based on use of an entraincent scrubber.
Kefere.ices |4 - 16 Controlled emission factors are based on use of .1 Jet entrjlnment scrubber.
We'. rcrubh..ra are standard process equipment ou drum granulacori. Unc;ncroll«d ealtslona were
measured at Che scrubber Iniec.
l-
,-PA test dat& indicated a rsnge of 0.955 - 1.20 Kg/Mg (1.91 2.40 Ib/tar).
FACTOR RATING: C; Rjfarenr.e 1.
FACT1R RATING: C; Refecer.cf 1.
Fond and ARrieul tur.'i I Indus-try
-------
Urea manufacturers presently contro. partirulate matter emissions from
prill towers, cooler?, granulators and bagging operations. With the
exception cf bagging operations, urea emission sources usually are
controlled with vet scrubbers. The preference of scrubber systems over dry
collection systems Is primarily for the easy recycling of dissolved urea
collected in the device. Scrubber liquors are recycled to the solution
concentration process to eliminate waste disposal problems and to recover
the urea collected.1
Fabric filters (baghouses) are used to control fugitive dust from
bagging operations, where humidities nre low and blinding of the bags is not
a problen.. However, many bagging operations are uncontrolled.1
References for Section 6.14
1. Urea Manufacturing Industry - Technical Document, EPA-450/3-8?-001,
U. S. Environmental Protection Agency, Research Triangle Park, NC,
January 1981.
2. D. F. Bress, M. W. Packbier, "The Startup of Two Major Urea Plants,"
Chemical Engineering Progress, May 1977, p. 80.
3. A. V. Slack, "Urea," Fe_rtiliz^r Development Trends, Toyes Development
corporation, Park Ridge, NJ, 1968, p. 121.
4, Written communication from J. M. Killen, Vistron Corporation, Lima, OH,
to D. R. Goodwin, U. S. Environmental Protection Agency, Research
Triangle Park, NC, December 21, 1978.
5. Written communication from J. P. Swanburg, Union Oil of California,
Brea, CA, to D. R. Goodwin, U, S. Environmental Protection Agency,
Research Triangle Park, NC, December 20, 1978.
6. Written communication from M. I. Bornstein and S. V. Capone, GCA
Corporation, Bedford, MA, to E. A. Noble, U. £. Environmental
Protection Agency, Research Triangle Park, NC, June 22, 1978.
7. Written communication from Gary MrAlister, U. S. Environmental
Protection Agency, Emission Measurement Branch, to Eric Noble, U. S.
Environmental Protection Agency, Industrial Studies Branch, Research
Triangle Park, NC, Jul> 28, 1983.
8. Formaldehyde Use in Urea-Based Fertilizers, Report of the Fertilizer
Institute's Formaldehyde Task Group, The Fertilizer Institute,
Washington, D. C.f February 4, 1983.
*. J. H. Cramer, "Urea Prill Tower Control Meeting 20% Opacity,"
Presented at the Fertilizer Institute Environmental Symposium,
New Orleans, LA, April 1980.
10. Written communication from M. I. Bornstein, GCA Corporation, Bedford,
MA, to E. A. Noble, U. S. Environmental Protection Agencv, Research
Triangle Perk, NC, August 2, 1978.
6.14-6 EMISSION FACTORS
-------
11. Written communication from M. I. Bornstein and S. V. Lapone, GCA
Ccrpuration, Bedford, MA, to E. A. Noble, U. S. Environmental
Protection Agency, Research Triangle Pirk, NC, June 23, 1978.
12. Written communication from J. P. Alexander, Agrico Chemical Company,
Donaldi.onville, LA, to D. K. Goodwin, U. S. Environmental Protection
Agency, NC, December 21, 1973.
13. Writttn coramuricaticn from N. E. Picquet, W. H. Grace and Company,
Memphis, TN, to D. R. Goodwin, U. S. Environmental Protection Agency,
Research Triangle Park, NC, Uecembei 14, 19/..',.
14. Urea Manufacture; Agrico Chemical Company Emission Test. Report, EMB
Report 79-NHF-13a, U. S. Environmental Protection Ap.enc} , hesearch
Triangle Park, NC', September 1980.
15. [jrea Nanufacture : Agrico Chemica 1 Company Emission Test Regprt, EMB
Report TS-NHF-/*, I!. S. Environmental Protection Agency, Research
Triangle Park, NC', April 1979.
16. Urea Manufacture; CF Industries L'tnisjion Test Report, EMB Report
78-NHF-8, U. S. Environmental Protectron Agency, Research Triangle
Park, NC, May 1979.
17. Urea Manufacture; Uni^n Oil of California Emission Test Report, EMB
Report 76-NHF-7. U. ',' Environmental Protection Agency, Research
Triangle Park, NT. October 1979.
18. Urea Manufacture: Union Oilof Califoinia Emission 'Test Report, EMB
Report 80-NHF-15, U. S. Environmental Protection Agency, Research
Triangle Park, NC, September 1980.
19. Urea Manufacture; W. R_. Grace and Company Em'ssion__Test Report, EMB
Report 78-NHF-3, U. S. Environreental Protection Agency, Research
Triangle Park, NC, December 1979.
20. Urea Manufacture: ReichholJ Chc-mlcals Emission Ti'st Rdpurt, EMB Report
80-NHF-14, U. S. Environmental Protection Agen..\. , Rt.-jearch Triangle
Park, NC, August 1980.
nnd A^'.r irw ] tur;, J Indu.'^ry 6.14-7
-------
f,. 15 BEEF CATTLE FEEDLOTS
6.15.1 General1
A bed' cattle ftf-uiut is an area in which beef nnirraU are confined ('>r fattening prior i<> ma;-!,i>tmp.
Th>s I'.ittening. ur finis.: feeding, typically lasts four to five months, during which lime the cattle are feu
a lii^'li cnrrt* ration of feed grains and/or forage.
'ecdldis tangriii capjciiy froin several head up to 100,000 cattle, 01 the 146. (XX) beef r.ittln r>ed-
Inls in the IS in I'iTS. 2,040 feedlots had a ca parity of more than 1,000 h.'ari, marketing 65 percent of all
llr.ish fed beet cattle. Aniind! density in fmilo :? is generally in the range of 1?.500 (o 125.000 heid/km2.
During it* ;-ia\ in a feedlot. a beef animal will produce over 450 kg of manure (dry weight ). Wei
production is typically about 27 kg per (Jay per h^ac1, usually deposited un less than 20 m2 of surface.
Because of the prodigious quantity of manure produced in a feedlol, periodic removal is necessary to
prevent unacceptable accumulations. Must cattle manure is applied to nearby land as fe rtilizer for feed
grain produt 'ion. while some is- laguuned, dumped on wastelands, or disposed of through incineration.
liming, o pilling. Manure removal frequencies are dictated in part by climatic condition*, animal comfort.
IjLor scheduling, and air and nater pollution control potentials. Typically, manure removal is conducted
Irorn one to three times Ker year, When disposal is not immediately po>sible after removal, tlu :ncnnre inuv
he stockpiled on a nearby open site.
The leadir.p stales in the industry are Texas. Nebraska, Iowa. Kansas, Colorado. California, and
Iliini.'? The?'- -tales contribute 75 percent of all feed cattle marketed and contain 72 percent of ihc tredlots
greater than 1000 head capacity. Feedlots are generally located in low population density regions with
access to major transportation routes,
6.15.2 Emissions and Controls'
Air pollution from fecdlots originates from several points in a feedlol operation, including the hoWing
pens, runoff holding pouds. and alleyways among pens. Major pollutants of concern include fugitive par-
liculate, ammonia and various malodorous gases.
>i- paniculate is generated several way*. Cattle movement within the holding ptns is a primary
sourre. Dus! i« als-o penerateti h\ wind acting on the dried surfaces and by vehicular tnfflr on alleyways
among the pent, Fugitive paniculate emissions from feedluis arr -.imposed largely of soil dust and dried
manure. The pottniial ioi dust generation is greatly increased dui e prolonged drv periods if.g.. frum late
spring to midsummer ir, the Southwest), and when a loose. dr> pad of soil and manure is Allowed to build
up in :he pens.
Xmmi'ir.ia i* 'he predominant gaseous pol'utant emitted from feedlols. Ammonia i* a rc*ult of jnaen.bic
deciinii'.ojiitinii i»f fecdlor surfaces a? weL as volatilization frum urine. Ammonia r missions are ^enernllv
in< rra- ed when conditions luvor anaernhir decay. For example, although '2.5 to 40 percent moiMuie le\els
are necessary or, fecdlot surfaces for aerobic decomposition (which is odorless), too much rain or
vt jt-ruiM. resulting jn puddling and wet spots, can trigger increased ammonia production. Amnonia forma-
tion may also occur wh».i anaerobic conditions exist in the manure stockpile? and runoff holding ponds.
In general, higher amrn'triia emissions are associated with higher temper-mire* and humidit\. overly wet
condition*, and ffedloi disturbance* such as mounding or manure removal.
A number ol extremely odorous compounds (amines'. *u;fide.-. rncrcaptaiir) rna> al^o ^esult fruin
anariohic -jecorn position of solid manure beneath the feedlol >urface a< w-»-li a' in (he runoff holding pond'-.
~'79 Feud and Agricultural Industry 6.15-1
-------
. the same conditions lhal favor ammonia pn>du<->i"r. will enhance ihe pvnluiion nfthese other
gas;-.-. JS well.
No air pollutsnl control devices are applied to feed lots because of the fugitive nature ol'tlu- > minion*.
The !r..'M effective rontrois involve various housekeeping measures designed to eliminate condition that
ijvui ihr generation of du>l arid odors. For example, measures, 'hat "ielp to maintain sufficient mi'istuie
level* in tlif feedlut surtat't areas and manuri stockpiles Kill reduce trie generation of Hust. One »1 the most
effective oust control techniques is periodic application of water lo the dry feedlot iurface, liy either per-
manent sprinkling systems or mobile tank trucks. However, care must be taken to avoid overwatering.
whirl) can causr vx-l spot* conducive to anaerohir decay and subsequent malodors. Incrt-asing the cattle
densiu in tilt- pens may also help maintain high enough moisture levels lo limit particular generation.
In addition, some dust control is effected by minimizing the accumulation of drv and pulverized manure on
the surfaces of the feedlots. A maximum depth nf 2 to 8 rm of loose, dry manure is recommended for
increasing the effectiveness jf dust control procedure*.
Odor auri ammonia control are best effected by housekeeping measures that enhancr ?er<'hic rallver
than jnaerobic decomposition of the cattle waste- For example, besides rcdui inji du^t cini«>i»ns.
-prinkling pruvides moisture for aerobic biode^rddalicn ol the manure, (joud drainage murt !)e pro^!ded.
honevei. anu ovTwatenng must be avoided. Deep accumulations of manure or slurry consistency can
optimize anaerobic conditions. Hence, feedU'l surfaces should be periodically scraped to remov such
accumulations. Scraping should be done carefuQy. so that only the surface layer is disturbed. Manure
stockpiles should not be allowed to get too large, too wet. or encrusted, and they should be disposed of
within four «.r five days. If the stockpiles are eompo-ted. the manure should be piled in k»ng narrow \*in-
tlniws tu allu* ,ic<'f<- for turning the pile< in promote aii'iliic conditions und t.j cauble rapid control ol
spontaneous combustion fires. Anaerobic conditions can bf reduced in runoff holding ponds \t\ removing
-olidi iron tli.> uinoff, by adding more w.ter ti> the ponds lo dilute the nutrient content, and by acrdiioh
it the »uifj< e. Runoff water aUo may be treated clieinicully to i-uppress the release of mal'xi' "•'".:- 4: i--~.
tmis?-ion t these factor; are more fully discussed in ihe footnote to Tabl>
ft. 1.V1. Ihe reader should consult Reference 1 for a detailed discussion of the emifsiu.if and fi.nti >l
oii available mi beef cattle fe -dlots.
6.13-2 EMISSION FACTORS 7/79
-------
Table 6.15-1. EMISSION FACTORS FOR BEEF CATTLE FEEDLOTS*
EMISSION FACTOR RATING: E
Pollutant
Participate6
Ammon:ac
Amines0
Total sulfur compoundsc
Feed!ot capacity basis
!b (kg) per day per
1 000 head capacity
280 (130)
11 (5)
0.4 (0.2)
1.7(0.8)
Feedlct throughput basis
ton (metric Ion) per
1000 head throughput
27 (25)
1.1 (1)
0.044 (0 04)
0.15 (0.14)
(actors represent general leedlo'. operations with no houseKefcp. ij measures for air pollution control
Bocausa of the limited data available on emissons and the nature of the techniques jtilized to develop emission
factors. Table 6 15-1 should only ti used I- develop orrttr-ot-rrag.ntudi estimates of feedlotemissons All tacws
are based on inlorrration compiled in Reference I
DThese factors represent emissii ns during a dry season at a feeolot where watering as a dist control measure wou'a
not be a common practice. No data are available to estimate emission factors 1 or leedlots during periods o'abundant
precipitation or where watering and uth«r housekeeping measui^s are employed lor djst control.
LThe;o factors represent emission fa-'ors lor leedlols that havr rot been chemically treated and where no special
housekreping measures are employed for odor control
Reference for Section 6.15
1. J.A. Peters and T R. Bkokv- Rfjfarch Tiianjilc I'ark. \C. June 1977.
7/79
Food and Aprirultural Industry
6.15-3
-------
6.16 DEFOLIATION AM) IIAKVESTIM; OF CO';TON
6.16.1 General
W hcre\ei it i-. thrown in I he I > . cult mi i- defoliated ni di-iccaled prior li» hanc-i. [)i toli.i'it- in used
on I he taller v ai elir- o| nil -II which UH r.ui liine picked )m lint and -ecd coll nu. « I: i It- •-!<•< Mill- ti»'iallv
jn1 used iin -hurl. -I'M ni'triHil t i>ti4in vanehc- o| loner virltl lh.il Jie liui vr-ted by inn h.tni. :il -trippd
ei|uipMieril. Mure I luii W ivrceni ut I hi- nat.oiud collnr. aiv.t i- har^i -ted niei h.inicalK . I In Uv« Miii''t|>al
harvest method.- .in- machine picking. w;'h 70 percent "I the li;mc-t trom ft] pen cut iri|>|ini|! is linnl >rl i hicll> >t> lh«-1' y |ilritn*<•«- iu<-.>
IIP initiatril h> drtiu^hi slrc<>. low leni|M'r;iliir<'.- or di.-ca-c. «>i it inav IK- < lieinii all> imli.ccrl h\ IHJIK jil\
jpplifd Jel'oliHiit djifiils or l>y u\erlcrt'liiuiiini. Thi1 proof" helps Indeed plants in return in ,KI ni-d jm'i-
tiun. ri'niii\c-i tin- iruves which fan rlug the >-piiulles ui tin- pit k'nji niaciniu- unJ ? train tli<- tihci. ai cclci Jlr."
I lie opening id iiialure Iiolls. jnd redni <•- in til ro!<. He-it < at inn li\ cliciniedl- i- tlu.1 la!o <»n tin1 pi-int. 11 n v.-l-;u.l
rlieri'u-uls an- applied to nutun us \* iilei-ltjsfd syrax. t'il!,i'r t\ aircrall or h\ a (rrujntj nuii'line.
Mechanical cotton pickers, us !()<• name implies, pick liirks »i src«l cutton Ivmii npcii luti'm It-ill* a'itt
lejve the einplv burs an-.l unopencil lutlls 0:1 tin1 plant. Hf'|ui'inji i>nl> o|ic optiiilor, t*pii ;'.! iniidcrn picKei-
are self prupel'fd and ( an -imultaneoiis]\ h.irvc*t two rows of cotton at d sueed ol I.I '.o 1.6 inetci-, per
second l2.5 • 3.6 nii.li). \\heii the p.ckei liaslcel (tfl- (llled i\itli i-('c drjulirallv ui-i d Uil'l tilled, the top s* iny- nper!.
allowing the ccillon to lall into the trailer. \^ hen the trailer i- lull, it is pulied l'iviii the 1'jeltl. usually In pi< k-
up truck, and taken ID a coiton tiin.
Merhanical culir.n strippers :.%mo\e upen and unopened l>olls. ulmit: with Imis. led\c> and sti in> frmn
cotton plants, leaving only hare branches. Trai'loi-tnuimled. truc'or-piilleil or •sell |»n|iell.-(i. >tripper-
require only one ope rat ur. They hardest from one In four row* of cut Inn at speed* <•'' ] .8 !<• 2.7 in. ^ ( t. 0 -
6.0 111,1 hi. After the colt on is stripped. H enlt •* a ( oincNinj.' -\ stem thiil i -arm's it frmn the si tipping unit In
an elevator. Mnst conveyers utilize either ,ni(i<'is or a -erit s ol loliilin^; -pike-1 out lied c \ltnilei.- In nun c !l;e
cotton, acconiplisliini; sonic < lca,iinj: 1-y niovint: the (otton o\ ei peilouiled. -lotted ur wire mesh -CM c.'i.
Drv plant material (burs, -terns and leaies) i- crushed ami dn |»pe(| tliruu^li npenir.j:- ;n the t,ro,nnl. Hlnwn
air if sumetirnes used to as-i>t cleaiiinji.
6.16.2 Emissions and (^onlrols
Emission factor for i':u- dnft;nu nf major cheniir-als flpi'Jicd to c niton arc compiled frmn l:u Mtuu- .HM]
reporltd in Kefertnci 1. in addition, drift losses from arsenic acH spruyinn were developed bv (leid
le-tini;. '1 VM) nfl-iaigc-l roUeotinn stalimi^. with si\ air -uniplers ea as ;n turn a-ed t»r the lin.il t'inis-i"ii
la; Inr < jlciilalinn i im enu-siun- ,K i-ur from July to O< tuber, preceding: bv I wo « eeks -he period i f h;iMc--l
in each cotton pnxiucinii region. T he drift emission factor (or ar-enir ar>d > ei^ht times If.v <-r :han prc-
vioii-ly estimated, since FJrfereni e I used a prnund rip ritlher than an airplane, ard herause oi (fie In*. MI!J
til.ity of arsenic acid. \ ariou- niei'ioils if ciin'.rnlliug diop size, proper tuning rit application. JIH! iiiMii.,rir.i
lion of rquipmenl aie piaclii es whicij fun leducr orif; ht'a^U. fluid additives h;;vo 'i- .-n »'ii :h.j' t:-.
create the vi*>cusily nl the spra\ Inrniuldtii'ii, and diu- decre .se ihe number n} Slue lin.pli 1- c )(X) ^;tri!.
Food and Apriiulltiral lmlii*,lr> 6.16-1
-------
Spra> nuzzlr doign and orientation also control the droplet size spectrum. Drill emission factors for the
defoliation of desiccation of cuttun art' listed in Table 6.16-1.
Table 6.16-1, EMISSION FACTORS FOR
DEFOLIATION OR DESICCATION OF COTTON1
EMISSION FACTOR RATING. C
Emission factor6
ruiiuidiu
Ib/ton
Sodium chlorate 20.0
DEF 200
Arsenic acid 12.2
Paraquat
20.0
g/kg
10.0
100
6.1
10.0
'Re.erence 1
"Factor is in terms cl quantity of drift par quantity applies
Three unit operations are involved in mr rhanical harvesting of cotton: harvesting, trailer loadmglbaskel
dumpingi and transport of trailers in the field. Emissions from these operation!- are in the form of solid
particulars. Paniculate emissions (<" ^m mean at rodynamic diprneter) from these operations were de-
veloped in Referen?e 2. The participates are composed mainly of raw collon duel and solid dust, which
contains fr-e silica. Minor emission? include small quantities of pesticide, defoliant and desiccant residues
that are present in the emitted parliculates. Dust concentrations from harvesting were measured by
following e.ich harvesting machine through the field at a constant distance directly downwind from the
machine, while slaying in the viiihlp plume centerline. The procedure for trailer loading was the sail e.
but since the tra'ler is stationary while ix.-ing IO.HI f J. ii was necessary only to stand a fixed distance
directly downwind from the trailer while the plume or putf passed over. Reading wrrt taken upwind of all
field activity to get background concent-ations. Paniculate emission factor* for the principal types of
collon harvesting operations i ihe L.S are shown in fable 6.16-2. The factor* Hie based on average
machine speed of 1.34 mis (3.0 mph) for pickers and 2.2 j m/'» (5.03 mphll'or strippers, on a basket capacity
of 109 kg 1240 lb-. on a trailer capacity of 6 baskets, nn a lint cotton yield of 63.0 metric ton* km2' 1. J7 bale'
acrei for pickers ar.d 41.2 metrir tunvkm''11.77 bale'acrri for strippers, and on a transport speed of 4.47 nv'»
(10.0 mph). Analysis of ^articulate sample' showed average free silica content of 7.9 percent for mechan-
ical cotton picking and 23 percent fur mechanical cotton stripping. Estimated maximum percentages for
pesticides, defoliant* and de«iccant? from harv»«tint ;m> also noted in T?.blt 6.16-2. No current cotton
harvesting • quipment <.r practices provide lor control of emissions. In fact, equipment design and operat-
ing practice* tend to maximize emissions. Prehanesl Irtatnicnt (defoliation
-------
Table 6.16-2. PARTICIPATE EMISSION FACTORS FOR COTTON HARVESTING OPERATIONS*
EMISSION FACTOR RATING: C
Type of harvester
Pinker0
Two-row, with basket
Harvesting
>JL
km7
46
Stripper0
Two-row, pulleo trailer ! 74
Two-row, with basket
2.3
Foul-row. w,th basket 2.3
Weighted average6
4.3
ib
mF
2.6
Trailer
loading
J*%
Km2
070
42 1 -b
13
13
24
lb
rnF
.40
.092 I 52
.092 I 52
.056
32
Transport
]
-^
Km*
.43
28
.28
28
28
fb
ml3"
2.5
1.6
1.6
1.6
1.6
Total
J9 two-row models with mounted
baskets
References for 3eclfon 6.16
1 J .V Peters and T. H. B!a< kwoicj. Suurcf \ wmtmt: Defohi nun cif'Cnitun-Stiitr of ihr Art. EPA-600'2 " 07(j.
I'.S. Envirunmemai Protection Agents. H*;farch Triangle 'ark. N(J. Julv 1977.
2 J ^ . jinyder ind T. R. BJackwood. Source \iseisnifnt: \l (-hunim! Hantstiup ifCotten-Stale ot th? Art, EPA-
600'2-77-l()7d. I >. LnMrunmrntal I'ruln-tiun \|ieni>. IVs.-arcli Triangle F'ark. \l". July 1977.
7/79
Food and Agricultural lnHu>,r\
6.16 3
-------
6.17 HARVESTING OF GRAIN
6.17.1 General
Harvesting of grain refers to the activities performed to obtain
the cereal kermis of the plant for grain or the entire plant for forage
and/or silage us«js. These activities are accomplished by machines that
cut, thresh, scieen, clean, bind, pick, and sheli the crops in the
field. Harvesting also includes loading harvested crops into trucks and
transporting crops on the grain field.
Crops harvested for their cereal kernels are cut as close as
possible to the inflorescence (the rlowering portion containing the
kernels). This portior is threshed, screened and cleaned to separate
the kernels. The grain Is stored in thlr\ (t.\7
-------
measured at the visible plume centerline and at a constant distance
behind the combines. For product loading, since the trailer is station-
ary while being loaded, it was necessary only to take measurements f.
fixed distance downwind from the trailer while the plume or puff passed
over. The concentration measured for harvesting and loading was applied
to a point source atmospheric diffusion model to calculate the source
emission rate. For field transport, the air samplers were again placed
a fixed distance downwind from ihe path of the truck, but this time the
cancentration measured was applied to a line source diffusion model.
Readings taken upwind of all field activity gave background concen-
trations. Particulate emission factors for wheat and sorghum harvesting
operations are shown in Table 6.17-1.
There are no control techniques specifically implemented for the
reduction of air pollution emissions from grain harvesting. However,
several practices and occurences do affect emission rates and concen-
tration. The use of terraces, contouring, and stripcropping to inhibit
soil erosion will suppress the entrainment of harvested crop fragments
in the wind. Shelterhelts, positioned perpendicular to the prevailing
wind, will lower emissions by reducing the *:ind velocity across the
field. By minimizing tillage and avoiding residue burning, the soil
will remain consolidated and less prone to disturbance from transport
activities.
Table 6.17-1. EMISSION RAITS/KACTORS
GRAIN3
-ROM THE HARVESTING
EMISSION FACTOR RATING: 1)
Emission rate
i
Operation ,
Harvest
machine
Truck
loading
Field
transport
Ib/hr
0.027
0.014
0.37
Wheat
Sorghuir,
nig/sec
3.4
1.8
47.0
Ib/hr
0.18
j 0.014
10.37
mB/
23.
1,
47.
sec
0
8
0
Emiusion factor
c
Whfat Sorghum
lb/mi2
0.
0.
0.
96
07
65
2
g/km
170.0
12. r
110. D
lb/mi2
6,5
0.13
1.2
2
S/100
1100.0
22.0
200.0
Reference 1.
Assumptions from Reference 1 are an average combine speed of 3.36
nef.ers per second, combine swath width of 6.07 meters, and a field
^transport speed of 4.48 ireters per second.
"In addition to Note h, t..^fiimptirmK are a truck loading time of six
minutes, a truck capacity of .052 km2 for wheat and .029 km? for
soighum, and a filed truck travel time of 125 seconds per load.
FAMOUS
2/81!
-------
Reference for Section 1.14
1. R. A. W&chcen and T. R. Blackvood, Source Assessment: Harvesting
of Grain,Stete pt the Art. EPA-600/2-79-107f, U. S. Environmental
Protection Agency, Research Triangle Park, NC, July 1977.
tiiul \nri( nllnnil hi
-------
6.18 AMMONIUM SULFATE MANUFACTURE
6.18.1 General
Ammonium sulfate, [NH4]2S04, Is commo/ily used as A fertilizer.
About 90 percent of ammonium sulfate is produced by three types of
facilities, caprolactam byproduct, synthetic, and coke oven byproduct
plants. The remainder ia produced as a byproduct of nickel Jianu-
far.ture from ore concentrates, methyl methaorylate manufacture, and
ammonia scrubbing at tall gas at r^furic acid plants.
During the manufacture of caprolactam, !CH2]5L.OHN, ammonium
sulfate is produced from the oximation process stream and the
rearrangement reaction stream. Synthetic ammonium sulfate is
produced by the direct combination of ammonia and sulfurit scld in
a reactor. Coke oven byproduct ammonium sulfate is produced by
reacting ammonia recovered from coke oven offgas with sulfuric
acid. Figure 6.18-1 is a process flow diagram for each of the
three primary commercial processes.
After formation of the. ammonium sulfate solution, operations
of each proceed are similar. Ammonium sulfate crystal* are formed
by continuously circulating an ammonium sulfate liquor through an
evaporator to thicken the solution. Ammviium sulfate crystal* are
separated from the liquor In the centrifuge. The* saturated liquor
IB returned to the dilute nrmonium sulfate brine of the evaporator.
The crystals, with about 1 to 2.5 percent moisture by weight after
the centrifuge, arc fed to either a fluidized bed or rotary drum
dryer. Fluid-Ued bed dryers are continuously steam heated, and
rotary dryers are either directly fired with oil or natural gas, or
they use steam heated air. At coke oven byproduct plants, rotary
driua dryers may be useJ in place of a centrifuge anc.1 dryer. On the
filter of these dryers, a crystal layer is deposited which is
removed from the drum by a scraper or a knife.
The volume of ammonium sulfate in the dryer exhaast gas varies
jr core; ing to production process nn£ dryer type. A gao flox rate of
620 scm/Mg of product (20,000 set/ton) is considered representative
of a direct fired rotary drum dryer. A gas flow of 2,500 scm/Mg of
product (80,000 scf/ton) is considered representative oi: a steam
heated fluidLzed bed dryer. Dryer exhaust gases are passed through
a particulate collection device, usually a wet scrubber, for product
recovery snd for pollution control.
The ammonium sulfate crysta?s are conveyed from the dryer to
an enclosure where they are screened to product specifications,
generally to coai e and fine products. The screening is enclosed
to control dust in the building.
4/31 Food and Agricultural Industry t.18-1
-------
00
Caprolactum Byproduct
I/I
I/I
I— c
o
z
n
H
o
Synthetic AS
NH3|
II2SO
35-40%
A.S Solution
Generation
\B
Keac;;or
t *
Steam Cond.
Stfiam ^
CrystalLizer
(Evaporator)
._ ^ To Atin.
Icond.
Vacuum i
System J
Vacuum
System
t 1
Sfeam Cond.
1— k
To Atm.
(Saturator)
Coke Oven Byproduct
Particulate and VOC Emissions
t_
Scrubber
or
Baghouse
n_ oCJ , ^^^^^w
2 4^
Reactor
(SaLurator)
Centrituge
Steam
Cond.
Ammonium Sulfate
Steam
1 •—+ Cond .
•e-
oo
Figure 6.18-1. Diagram ol Ammonium Sulfate (AS) processes.
-------
6.18.2 Emissions and Controls
Ammonium aulfate particulate is r.he principal pollutant emitted
to the atmosphere from the manufacturing plants, nearly all of it
being contained in the gaseous exhaust of the dryers. Other plant
processes, such as evaporation, screening, and materials handling,
are not significant sources of emissions.
The particulate emission rate of a dryer depends on the gas
velocity and the particle size distribution. Since gas velocity
varies according to the dryer type, emission rates also vary.
Generally, the gas velocity of fluidized bed dryers is higher than
for most rotary drum dryer0, and particulate <=>mi.<,^lon rites are
also higher. The smaller the r,artlcle, the easier it is reivovd by
the gas stream of either tyoe ?f dryi?r.
At caprolactam byproduct plants, volatile organic compounds
(VOC) are emitted from the dryers. Emissions of caprolactam vapor
are at least two orders of magnitude lower than the particulate
emissions.
Wet scrubbers, such as venturi and centrifuge, are most suitable
for reducing particulate emissions from the dr/ers. W«t scrubbers
use process streams as the scrubbing liquid. This allows the
collected particulate to be recycled easily to the production
system.
Table 6.18-1 shows the uncontrolled and controlled emission
factors for the various dryer types. The /OC emissions shown in
Table 6.18-1 apply only to caprolactam byproduct plants which may
use either a fluidized bed or rotary drum dryer.
TABLE 6.18-1. EMISSION FACTORS FOR AMMONIUM SULFATE MANUFACTURE3
EMISSION FACTOR RATING; U
Particulates VolatileOrganic Compounds
Type & Controls kg/Mg Ib/ton kg/MgIb/ton
Rotary dryers
Uncontrolled
Wet scrubber
Fluidized bed dryers
Uncontrolled
Wet scrubber
23
0.12
109
0.14
46
0.24
213
0.2U
0.74
U.ll
0.74
0.11
1.48
0.22
1.48
0.22
o
Expressed as emissions by weight per unit of ammonium sulfate
.production by weight.
VOC emissions occur only at caprolactam plants using either type
of dryer. The emissions are caprolactam vapor.
4/81 Food anc Agricultural Industry 6.18-3
-------
Reference for Section 6.18
^• Ammonium Sulfate Manufacture ~BackgroaneInformationfor Proposed
Emission Standards. EPA-450/3--79-034a. U.S. Environmental Protection
Agency, Research Triangle Park, NC, December 1979.
b.18-4 EMISSION FACTORS A/81
-------
7.1 PRIMARY ALUMINUM PRODUCTION
7.1.1 Process Description1'^
The base ore for primary aluminum production Is bauxite, a hyJ rated
oxide of aluminum consisting of 30 to 70 percent aluninj (^1203) and leaser
amounts of Iron, silicon and titanium. The b;u>ite ore Is f'st purified to
alumina by the Bayer process, and this Is then red jced to elemental aluminum.
The production of alumina and Che reduction of alumina to Aluminum are seldom
accomplished at the aane facility. A schematic diagram of the primary
production of aluminum Id shown at Figure 7.1-1.
Ir< the Bayer process, the ore is dried, ground In ball mills and mixed
with a leaching solution of sodium hydroxide at an elevated temperature and
pressure, producing a sodium alumina tc solution which is 3° oa rated from the
bau. Ice Impurities and cooled. As the solution cools, the hydra ted aluminun
oxide (Al-203 . 3H2U) precipitates. FJ! lowing separation and washing to
rtoo/e Iron ox!4e, silica and other Impurities, the hyd -rated aluminum oxide
la dried and calcined to produce a crystalline form of alumina (A1203),
advantageous for electrolysis.
Aluminum metal Is manufactured by the Hall-Heroult process, which
Involves the electrolytic reduction of alumina dissolved in s molten salt
bath of cryolite (^AlFg) and various salt additives:
2A1203 Electrolysis 4A1 + 302 (1)
Ali-.iina » Aluminum Oxygen
(reduction)
The electrolytic reduction occurs In shallow rectangular cells, -r "pecs",
which are ate^l shells lined with carbon. Carbon electrodes extend Into t*ie
pot and serve as the anodes, and the carbon lining the steel shel-i is the cathode
Molten cryolite functions as both the electrolyte and the solvent for the
alumina. Electrical resistance to the current pr.as'ng between the electrodes
generates heat that maintains cell operating temperatures between 950* a ad
1000°C (1730° and 1830"F). Aluminum is deposited at the cathode, where It
remains as molten metal below Che surface of the cryolite br), and vertical etud Soderberg
(VSS). Most of the aluminum produced in the U. 5. ie processed In PB cells.
Anodes are produced as aii ancillary operation ft the re-iur. MOP. plant.
'.n the paste preparation ^lant, petroleum cok« Is mixed wJ.th a pitch binder
4/81 Metallurgical Industry 7.1-1
-------
BAUXITE
A SODIUM
f HYDROXIDE
TO CONTROL DEVICE
Inn Y IN r. j. 1 -
/
1 ALUMINUM
SETTLING
CHAMBER
•••••^•V^K^WIIV -^^^^^^^^^^
• If • •
DILUTE
SODIUM
HYDROXIDE
-*-
HYDROXIDE
CRYSTALLIZER -
DILUTION
WATER
1 REDM
1 (IMPURI
\
FILTER
UD
TIES)
AQUEOUS SODIUM
ALUHHNATE
TO CONTROL
DEVICE
CALCINER
SPENT
ELECTRODES
ALUMINA
ANODE
PASTE
ELECTROLYTE
1
ANCDE PASTE
TO CONTROL DF.VICE
BAKING
FURNACE
BAKED
ANODES
TO CONTROL DEVICE
PREBAKE
REDUCTION
CELL
TO CONTROL DEVICE
HORIZONTAL
OR VERTICAL
SODERBERG
REDUCTION CELL
Figure 7.1-1. Schematic diagram ol primary aluminum production process.
7.1-2
EMISSION FACTORS
4/81
-------
to form a paste which Is use- for Soderberg cell anodes, and for green anodes
for prebake cells. Paste preparation includes crushing, grinding and screen-
ing of coke and cleaned spent anodes (butts), and blending with a pitch binder
in a atean Jacketed mixer. For Soderberg anrdea, thu thick paste mixture is
transferred direct.1, y to Che pot room for addition to the anode casings. In
prebake anode preparatlc , the paste mixture Is molded to form self supporting
green anode blocks. The blocks are baked in a direct fire<* ring furnace or an
Indirect fired tunnel kiln. Baked anodes are then transferred to the roddlng
room, where the electrodes are attached. Volatile organic vapors from the pitch
paste are emitted during anode baking, and most are destroyed in the baling
furnace. The baked anodes, typicall/ 14 to ?4 per cell, are attached to metal
rods and serve as replaceable anodes.
TABLE 7.1-1. RAW MATERIAL AND ENERGY REQUIREMENTS FOR ALUMINUM PRODUCTION
Parameter Typical value
Cell operating temperature ~ 950°C (~ 1740°F)
Current through pot line 60,000 - 125,000 amperes
Voltage drop per cell 4.3 - 5-2
Current efficiency 85 - 90%
Energy required 13.2 - 18.7 kwh/kg aluminum
(6.0 - 8.5 kvh/lb aluilnum)
Weight alumina consumed 1.89 - 1.92 kg(lb) Al203/kg(lb) aluminum
Weight electrolyte
fluoride consumed 0.03 - 0.10 kg(lb) fluorlde/kg(lb) aluminum
Weight carbon electrode
consumed 0.45 - 0.55 kg(lb) electrode/kg(lb) aluminum
In the electrolytic reduction of aiumJna, the carbon anodes ore lowered
Into the cell and consumed at a rate of about 2.5 centimeters (1 Inch) per day.
Prebal 3d cells are preferred over Soderberg cells for their lower powt*r require-
aents, reduced generation of volatile pitch vapors from the carbon anodes,
and provision for better cell hooding to capture emissions.
The second most commonly used reduction cell Is the horizontal stud
Soderberg (HSS). This type of rsll uses a "continuous" carbon anode. Green
anode paate IB periodically added at the cop of the anode casing of the pot
and is baked by the heat of the cell to a solid carbon mass ae the material
moves down the casing. The cell casing consists of aluminum sheeting a: I
perforated steel channels, through which electrode connections (studs) are
Inserted horizontally Into the anod» paste. During reduction, ao the baking
anode Is lowered, the lower row of studs anr* the bottom channel are removed,
and the flexible electrical connectors arc moved to a higher row of studs.
High molecular weight organics from the ai.ode paste are released, along with
other cell emissions. The heavy tars can cause plugging of exhaust ducts,
fans and emission control equipment.
The vertical stud Soderberg (VSS) cell Is similar to the HSS cell, except
that the studs are mounted vertically in the anode paste. Gases from the VSS
4/81 Metallurgical Industry 7.1-3
-------
cells can be ducted to gas burners, and the tar and oil» combusted. The con-
struction of the HSS cell prevents the installation of an Integral gas collection
device, and hooding is restricted to a canopy or skirt e.t the base of the cell,
where th<> hot ar.c-de enters the cell bath.
Casting involves pouring molten aluminum into molds and cooling it with
water. &L some plants, before casting, the -no 1 ten aluminum may be batch treated
In furnaces to remove oxide, gareous impurities and active totals such as
sodium and magnesium. One process consists of adding a flux of chloride and
fluoride salt;; and then bubbling chlorine gis, usually mixed with an inert
gas, through the molten mixture. Chj.oi'lnu reacts with the impurities to form
HC1, \\20j and metal chloride emissions. i dross forus and floats on the
molten aluminum and Is removed before casting.^
7.1.2 Emissions and Controls1"^'10
Controlled and uncontrolled emission factors for total paniculate
matter, fluoride and sulfur oxldoo are presented in Table 7.1-2. Fugitive
participate and fluoride emission factor* for reduction cells are also pre-
sented in this Table*
In r.ho preparation of refined alumina from bauxite, large amounts j£
partlculates are generated during the calcining of hydrated aluminum oxide ,
but the economic value of this dust is such that extensive controls are
employed to reduce emissions to relatively small quantities. Small amounts
of partlculates are emitted from the b.uxite grinding and materials handling
processes.
Emissions from aluminum reduction processes consist primarily of gaseous
hydrogen fluoride and partlculate fluorides, alumina, carbon monoxide, vola-
tile organlcs, and sulfur dioxide from the reduction cells, and fluorides,
vaporized opanics and sulfur dioxide from the. anode baking furnaces.
The source of- fluoride emissions from reduction cells Is the fluoride
electrolyte, uhlch contains cryrllte, aluminum fluoride (A1F3), and fluorspar
(CaF2). For normal operation, the weight, or "bath", ratio of sodium fluo-
ride (NaF) to A1F3 Is Maintained between 1.36 and 1.43 by the addition of Aljf^,
This Increases the cell current efficiency and lowers the bath melt'ng point,
permitting lower operating temperature in the cell. Cell fluoride emissions
are decreased by lowering the operating temperature. The ratio of gaseouu
(mainly hydrogen fluoride and silicon tetrafluorlde) to partlculate fluorides
varies from 1.2 to 1.7 with PB and HSS cells, but attains a value of approx-
imately 3.0 wltr VSS cells.
Partlculate emissions froa reduction cells consist, of alumina and carbon
from cnodc dusting, cryolite, aluminum fluoride, calcium fluoride, chlolitc
(NasAi3Fi4) and ferric oxide. Representative size distributions for partlc-
ulatfe emissions froai PB cells and HSS cells are presented in Table 7.1-3.
Partlculates less than I micron In diameter epresent the largest fraction
(35 - 44 percent) for uncontrolled emissions. In one HSS cell, uncontrolled
parclcuiate emission1", from one HS3 c«?ll had a raass mean particle diameter of 5.5
microns. Thirty percent by ranss of 'ri'f_ p.'.rrlclea were 8'Jbmlcron, and 16 percent
were less than 0.2 microns in dlamt'tei. f
7.1-4 EMISSION FACTORS A/81
-------
oo
TABL!! 7.1-2. EMISSION FACTORS FOR PRIMARY ALUMINUM PRODUCTION PROCESSES'
F.MISSION FACTOR RATING: A
1-1
OQ
n
a
g.
£
Operation
Bauxite grinding
Uncontrolled
Spray toner
Floating bed ocrubber
Quench to war and
a pray acr««n
Electroatatle
precipf tator (ESP)
Aim In ua hydroilde
Calcining
Uncontrolled
Spray tower
Floating bad «c rubber
Quench tower
ESP
Anode baking furnace
Uocon trolled
Fugitive
Spray towrr
ESP
Dry alualna i- rubber
Prebake cell
Uncon tro 1 led
Fugl tlve
EalBslona to collector
Multiple cyclone*
Dry tlualna »c rubber
Dry ESF + apray toner
Spray tower
Floating bed acrubber
Coateo bag filter dry
scrubber
Croai flow packed bed
Dry + Mrcond P-tubbtr
Total
Participate*
Kf/Mg Ib/ton
3.0 *,0
0.9 1.6
0.85 1.7
0.5 1.0
0.06 0.12
100,0 200.0
30.0 60 .O
28.0 56.0
17.0 34.0
2.0 4.0
1.5 3.0
HA HA
0.575 0.75
0.375 0.75
0.03 0.06
«;.o 94.0
2.5 5.0
M.5 89.0
9.8 19.6
0.9 l.S
2.25 4.5
8.9 17.8
8.9 17.8
0.9 l.B
13.15 26.3
0.35 0.7
Pamriia
Fluoride (O)
kg/Kg Ib/COD
•eg Hag
Neg Mag
Fartlenlate
Flvorlda (P)
kg/Hg Ib/too
U SA
U HA
Ne|, »*8 ! •* RA
!
••• H«l
«te« Beg
Iteg Nag
"«8 "^8
Hejj Ueg
tfeg Beg
Meg Hag
0.45 0.9
NA 94
0.02 0 C4
0.02 0.04
0.0045 0.009
12.0 24.0
0.6 1.2
11.4 22.8
11.4 22. b
0.1 0.2
0.7 1.4
0.7 1.4
0.25 0.5
1.7 1.4
3.25 6.7
t-2 0,4
•A HA
•A HA
•A HA
HA HA
•A HA
•A HA
•A HA
0.05 0.1
MA MA
0.015 0.03
C-,015 C.03
O.OO1 0.002
10.0 20.0
0.5 1.0
9.5 19. C
2.1 4.2
0.2 0.4
1.7 3.4
1.9 3.8
1.9 3. 8
0.2 0.4
2.8 5.6
0.15 0.3
Sulfur
Gzldea
kg/Mg Ib/un
MA MA
HA MA
NA NA
HA «A
NA «A
NA NA
NA NA
NA NA
NA NA
NA NA
c c
NA NA
NA NA
HA NA
NA NA
c c
NA NA
NA NA
NA NA
•JA NA
NA NA
NA HA
NA NA
NA KJ
NA MA
NA NA
Reference*
1.*
1.3
1.3
1.3
1.3
1.3
1.3
1,3
1.3
1.3
2.9,10
9
2
1.9
1,2,9,10
Z,»
2
1
2,9
1.9
I
i
2
9
9
-------
TABLE 7.i-2 (CONT.J. ZMISSION FACTORS FOR PRIMARY ALUMINUM PRODUCTION PROCESSES
EMISSION FACTOR RATING: A
n
SE
H
O
7°
in
Operation
Vertical Soderberg ttud ceil
Uncontrolled
Fugitive
Eaisilon* to collector
Spray toner
Penturl scrubber
Multiple rye lone 8
Cry alinlua »c rubber
Scrubber + ESP + spray
acreen -f acrubber
Horizontal Soderberg atud cell
Uococ:rolled
Fugitive
Kmlfalonm tu colltctci
Spray tower
Floating bed ic rubber
Scrubbei + weL ESP
Hcb ESF
Dry aluaitna ac rubber
Total.
Participate1*
K£/Mg ib/ton
39.0 76.0
«-0 12.0
13.0 66.0
8.25 16.J
1.3 2.6
16.5 32.0
0.65 1.3
3.i5 7.7
49. 0 96.0
5.0 10.0
44.0 M-0
11.0 22-0
9.7 19.*
n.9 L.B
0.9 1.8
0.9 i. a
Ca^eoia
?Ju>rld« (HT)
kl/Mj( Ib/too
16.5 33.0
2.«5 4.9
14.05 20.1
0.15 0.3
0.15 0.3
14.05 28.1
0.1S 0.3
0.75 1.5
11.0 22.0
1.1 2.2
9.9 19. 8
3.75 7.5
0.2 0.4
0.1 0.2
0.5 1.0
0.2 0.4
PartlcuLct*
Fliorldc (F)
kft/tfe Ib/ton
5.5 11.3
0.85 1.7
4.65 9.3
1.15 2.3
0.2 0.4
2.35 4.7
0.1 0.2
0.65 1.3
o.O 12.0
0.6 1.2
5.4 10.8
1.35 2.7
1.2 2.4
0.1 0.2
0.1 0.2
0.1 0.2
Sulfur
Omldea
kg/Kg Ib/ton
HI HA
HA HA
HA HA
NA HA
NA HA
uA HA
HA HA
HA HA
NA SA
HA HA
NA HA
NA NA
NA MA
DA HA
HA HA
HA HA
Beferdncea]
Z.9
3
9
2
2
2
2
2.9
2,9
2.9
2.9
2
2,9
9
9
'For bauxite grinding, expressed as kg/Ng (Ib/ton) of bamite procecaad. For calcining of alualniai hydroilde,
eipreHpd aa Vig/Hg (Ib/tnn) of alualau produced. All other factor* are per Mg (ton) of aiolten alnBlnin
product. Emlaalon factor* for fulfur oxlde3 bare C ratloji. HA • not available.
^Includes partlculate flmrldes.
c Anode b'klog furnace, uncoatrolled SO, emJaclon* (excluding furnace fuel coajbuatlno
20(C)(S)(1--»>1 ") M/Nf («')(C)(S)(1-.01
rTel»«V£ (reiJ'jr tlon) cell, uncontrolled 502
[0.4(C)(S)(K) Ib/tonJ
Where: C - Anode coniuaptlon* d'lrlng el*ctrolr>ll , Ib aooda cc^aiaiid/lb Al produced
S - I sulfur In anode before bakJng
R. - Z of to Lai SO 2 nltted by prebake (reduction) call*
*An(xl« con«iaiptlon weight !• weight of anode pnate (coke + pltr.h) before baking.
-------
TABLE 7.1-3. REPRESENTATIVE PARTICLE SIZE DISTRIBUTIONS OF UNCONTROLLED
EMISSIONS FROM PREBAKED AND HORIZONTAL STUO SODERBERG CELLS*
Size range !\i\
I
of control devices has been used to abate emissions from
reduction cells and anode baking furnaces. To control gaseous and partic-
ulate fluorides and participate emissions, one or more cypes of wet scrub-
bers (spray tower and chambers, quench towers, floating beds, packed beds,
Venturis, and self Induced sprays have been applied to all three types of
reduction cells and to anode baking furnaces. Also, parciculate control
methods such aa electrostatic prtclpltators (wet and dry), multiple cyclones
and dry alumina scrubbers (fluid bed, injected, and coated filter types) are
employed with baking furnace? ani on all three cell types. Also, the alumina
adsorption Ry«ttms are being used on all three cell types to control both
gaseous and paniculate fluorides by passing the pot offgaaes through the
entering ali^aln^ feed, whlrh adsorbc the fluorides. This technique has an
overall control efficiency of f>8 to 99 percent. Baghouues are then used to
collect residual fluorides entrained in the alumina and ID recycle them to
the reduction cells. Wet electrostatic preclpltators approach adsorption In
participate removal efficiency but must be coupled to a wet scrubber or
coated baghouse to catch hydro?«n flvorlde.
Scrubber systems also remove a portion of the S02 emissions. These
emissions could be reduced Ky w«t scrubbing cr by reducing the quantity of
sulfur In the anode coke and pitch, I.e., rnlclning the coke.
4/81
Metallurgical Industry
7.1-7
-------
In the hydrated aluminum oxide calcining, bauxite grinding and materials
handling operations, various dry dust collection devices (centrifugal collec-
tors, tuulclple cyclones, or electrostatic precipl tators and/or vet scrubbers)
have been used .
Potential sources of fugitive particular? emissions In the primary
aluminum Industry are bauxite grinding, materials handling, anode baking and
three types of reduction cells (see Table 7.1-2). These rugitlves probably
have particle slz« distributions similar to those presented In Table 7.1-3.
References for Section 7.1
1 . Engineering and Cost Effectiveness Study of Fluoride Emissions Control ,
Volume I, APT D- 0945, U. S. Environmental Protection Agevicy, Research
Triangle Park, NC , January 1972.
- ' Air Pol 1 ur. Ip n Control in the Primary Aluminum Industry , Volume I ,
EPA-45073-73-004a, U. S. Environmental Protection Agency, Research
Triangle Park, NC, July 1973.
3. Pa r 1 1 c ula t e Pollutant S y 9 1 ea_ S t ydy _, _Vo 1 ume I , APTD-0743, U. S. Environ-
mental Protection Agency, Research Triangle Park, NC , Hay 1971.
4. EL.Jtsf.lons from _ Wat Scrubbing System, Report Number Y-7730-E, York
Research Corp. , Stamford, CT, May L972.
•j . Smlssiors from Prlu^ry Aluminum Smelting Plant, Report Number Y-7730-B,
York Research Corp . ," Stamford , CT, June 1972.
6. Emissions from the Wet Scrubber System, Report Nuaber Y-7730-? , York
Resaarc-h Corp., Stamford, CT, June 1972.
7. 1. R. Hanna and M. J. t'llat, "Size Distribution o': Purt Iculates Emitted
from a Horizontal Spike Soderberg Aluminum Reduction Csll" , Journal of
.Ell'j Ai r Po-1_1 u c j-° " Co " r ro -1- As so c i ^A0 " • 11: 533-536, July 197 2~.
Ba ckground In.forma lion for Standards of Performance: Pi imar;^ Aluminum
Irdustry. Volume 1 ; Proposed Standards, EPA-£5Q7^-74-020a , U. S.
Efiviroiiiuuntal Protection Agency, Research Triangle Park, NC, October
9. Primary Aiinalnum; Guidelines for Contrc.l_j>f_ .'•"luorlde Emissions fiom
F.xlsiine Primary Alunvfnum Plants, EPA-4SO/2-7H-049b , U. S. Environmental
'^rofect'.on Agency, Research Triangle Park, NC, December 1979.
10. Writter communication from T. F. Albee, Reynolds Aluminum, illchm
-------
7.2 COKE MANUFACTURING
7.2.1 Process Description
Coking is the process of destructive distillation, or the henting
of coal in an atmosphere of low oxygen content. During this process,
organic compounds in the coal break down to yield gases and a relatively
involatile residue. The primary method for the manufacture of coke is
the byproducc method, which accounts fc?r more than 98 percent of U.S.
coke production.
The byproduct method is oriented (:o the recovery of gases prouuced
during the coking cycle. Narrow rectangular slot-type coking ovens are
constructed of silica brick, and a battery Is common1}' made up of a
aeries of 40 to 70 o£ these ovens interspaced with heating flues. A
.Urry car runs along the top of the coke battery, charging the ovens
with coal through ports. After each charging, the ports are sealed, and
heat IL supplied to the ovens by combustion of gases passing throi«f;li the
flues between the ovens. The fuels used in the combustion process are
natural gas, coke oven gas or blast furnace gas. Tn the ovens, coke ia
formed first near the brick walls and then toward the center, where
temperatures are 20008 - 2100°F (1100° - 1150°C). After a period of
16 - 110 hours, the coking process is complete. Coke is pushed by a ram
from the oven into a quenching car. The quenching car of hot coke is
moved by rail to the quench tower, where several thousand gallons of
water are used to cool the coke. The coke is allowed to dry and is
separated into various sizes for future use. See Figure 7.5-1 of this
document for a flow diagram of an integrated iron and steel plant which
contains the coking operations.
V.2.2 Emissions1
Participates, volatile organic compounds, carbon monoxide and other
emissions originate from the following byproduct coking operations: (1)
coal preheating (if used), (2) charging of coal into the incandescent
ovens, (3) oven leakage during the coking period, (4) pushing the cok<>
out of the ovens, (5) quenching the hot coke and (6) combustion stacks.
Gaseous emissions from the byproduct ovens during the coking process are
drawn off to a collerLing main and are subjected to various operati^as
for separating acmonia, coke oven gas, tar, phenol, light oil (benzene,
toluene, yylene) and pyridina. These unit operations are potential
sources of volatile organic compounds.
Oven charging operations and leakage ai.ound poorly sealed coke riven
doors aid lids are major sources of emissions from byproduct ovens.
Emissions also occur when finished coke is pushed into the quench cars
and during the quenr.hing operation. The combustion process is also a
source of pollutant emissions. As the combusting gases pass through the
cake oven heatii.g flues, emissions from the ovens nay leak j ito the
stream. Also, if the coke oven g
-------
Nl
I
10
n
hj
6
-#
in
o
o
TYPES OF AIR POLLUTION EMISSIONS
FROM COKE-OVEN BATTERIES
(T) Pushing emissions
(2) Charging emissions
(3) Door emissions
(7) Topside emissions
(5) Battery ur,Jerfire emissions
///SS///S/////////SY/'/////////////////
ol TheWesliMn
.inia AM PnltutiC'*
Ccnitn) As* .riiitKin)
-------
TABLE 7.2-1. EMISSION FACTORS FOR COKE MANUFACTURE3
EMISSION FACTOR ELATING: D (except participates)
C
OQ
O
4>
C
vO
renencers
Unennr rn]\fA
Controllprl by srnihhp*
Coal Ctur^liig
Hnrnntrolled
Co«ttrolleH larry rar
vanl«d to v^rub'jer
Sequeocl«l rr.artfini;
Door Leaki (Unron;rol'-',
Coke Punhlng
Su«D«nde4 pt-~c IculfltpTi
Uncontrolled (neisurrd In Hurc
wnLing coke aide •*•«•:?}
Controlled (miter T°n»»>
Total p*rt IculJvrea
(luipen.,ed pin dunt Fill)
Uncontrolled
Coot rolled !v*tti t?it?»)
Concrolled (encluaad colyl CUE"
and guide uenced en icrubbet)
(Concrolled br taffln)
(unconr ro
Q.2
fl.l
1.0
C.«
o.n:
n.1
9.29
Ib/to^i
Q.SI
0.47
2.D
I.I
n.oi*
l.S
C. ^li
S til fur
die* i HP*'
Ib/rnn llg/>lg Ib/ton
Ib/tor,
i^ll
Ib/ton kg/HK Ib/ton Lg/Ng
nl.c
lb/tnn
.1.01
3.or
0.1
n.6
o.oii t).o?
.J5 2.S
D.75 l.s
O.Oli
0.03 0.31
O.OC5 O.OI O.C'
O.OZ
0.06
0.05
O.I
nprcMcd mm »«lRh: ?«r unit wlxl>t n( caul
»*iS Indltarci no
4ati.
»J
•
I
•tefcriacra ^-t.
'••f«r«nc* 7. The mlf.ir >)loiiric Fic[or 1« taacil O' the lollovlnj rcprtxnt tl»« coidltloai: (i/ sulfur nontant of KM!
chir|»J to or-*-. 1? n.i wclghtX; (2) *bt>ut 31 neigh. Z of total tu'.fur In the crvtl cturg«d to tritn It tr«ncf«rr«d ta C>M
coke j operation, nhtre tho rut of th« iiulfur dlould* It dlKhcrftCi1 - *boal ) kg/In (ft Ib/tin) of
cool chirgod- «l«i (4) f
-------
Associated with the byproducc coke oven process arc open source fugit-
ive dust operations. These include material handling operations of unload-
ing, storing, grinding and sizing of coal, and (.tie screening, crushing,
storing and loading of coke. Fugitive emissions also come from vehicles
traveling on paved and unpaved surfaces. Th«se emissions and the parameters
that influence them are discussed in more detail in Section 7.5 and Chapter
11 of this document. The emission factors for coking operations are summar-
ized In Taole 7.2-1. Extensive information on the data used to develop the
partJculate emission factors is found in Reference 1.
References for Section 7.7
1. Pa r t i cu1ate Emission iactors ^Appli c a b1e to the Iron and Steel In-
dustry, ErA-<*50/A-79-028, U.S. Environmental Protection Agency,
Research Triangle Park, NC, September 1979.
2. Air Pollution by Coking Plants, United Nations Report: Economic Com-
misslon f-r Europe, ST/ECE/Coal/26, 1968.
3. R. W. Fullerton, "Impingement Baffles To Reduce Emissions from Coke
Quenching", Journal of the Air Pollution Control Association,
J_7:807-809, December J967.
4. R. B. Jacko, et al., By-product Coke Oven Pushing Operation; Total
andTrace Metal Particulate Emissions, Purdue University, West
Lafayettt, IN, June 27, 1976.
5. Control Techniques for Lead Aj.r Emissions. EPA-450/2-770-012, U.S.
Environmental Protection Agency, Research Triangle Park, NC, December
1977.
6. Mineral Industry Surveys: Weekly Coal Report No. 30%, Bureau of
Mines, U.T. Department of the Interior, Washington, DC, undated.
7. J. Varga and H. W. Lowniu, Jr., Flnfl Technological Report on: A
Systemb Analysis Study of the Integrated Iron and Stee] Industry,
HEW Contract. No. PH 22-68-65, Battelle Memorial Institute, Columbus,
OH, May 1969.
7.2-4 EMISSION FACTORS 12/31
-------
/.3 PRIMARY COPPER SMELTING
7 3.i Process Description'"^
In Che United States, copper Is produced fiom sulfide
-------
ORE CONCENTRATES WITH SILICA FLUXES
FUEL.
AIR-
ROASTING
CONVERTER SLAG (2% Cu)
FUEL-
AIR.
CALCINE
SMELTING
SLAG TO DUMP
(O.SS Cu)
AIB-
OFFGAS
MATTE (~40% Cu)
CONVERTING
-ft-OFKOAS
GREEN POLES OR CAS
FUIL
AIR
SLAG TO CONVERTER
BLISTER COPPER
FIRE REFINING
OFFGAS
AMODE COPPER (99.5% Cu)
TO ELECTROLYTIC REHNEflY
Figure 7.3—1. A conventional copper smelting process
7.3-2 EMISSION FACTORS
-------
Reverberator? furnace operation is a continuous process, with frequent
charging of Input materials and periodic tapping cf matte and sklnmlng of
slag. Reverberator? furnaces typically process from 800 tc 1,200 Mg (900 to
1,300 tons) of charge per day. Heat Is supplied by combustion of oil, gas or
pulverized coal. Furnace temperatures may exceed 1,500°C (2,730°F)U
For smelting in electric arc furnaces, heat is generated by the flow of
an electric current in submerged carbon electrodes lowered through
the furnace roof into the slag layer of th* molten bath. The feed generally
consists of dried concentrates or calcines, and charging wet concentrates is
avoided. The chemical and physical changes occurring in the molten bath
are sinilar to those occurring in the molren bath of a reverberatory furnace.
Also, the matte and slag tapping practices are similar at both furnaces.
Electric furnaces do not produce fuel combustion gases, so flow rates are
lower and SOj concentrations higher in effluent gas than In thit of reverber-
atory furnaces.
Flash furnace smelting combines the operations of roasting and smelting
to produce a high grade copper matte from concentrates and flux. In flash
smelting, dried ore concentrates and finely ground fluxes are Injected ~ogether
with oxygen, preheated air, or a mixture of both into a furnace of special
design, where temperature i«* maintained at ayproxln-scely 1,000°C (1,8309F).
Flash furnaces, in contrast to reverberatory arj electric furnaces, use the
heat generated from partial oxidation of their sulfide sulfur charge to
provide much or all of the energy (he.^t ) required for smelting. They also
produce ofCgas streams containing high concentrations of
Slag produced by flash furnace operations contains significantly higher
amounts of copper than does that from reverberatory or electric furnace
operations. As a resui.. , the flash furnace and converter slags produced at
flash smelters are treated in a slag cleaning furnace to recover the copper.
Slag cleaning furnaces usually are. small electric arc furnaces. The flash
f.irnace and converter slags ire charged to a slag cleaning furnace and are
allowed to settle under reducing conditions with the addition of coke or iron
sulfide. The copper, which is in oxide form in the Klag, is converted to
copper sulfide, subsequently removed from the furnace and charged to a
converter with the regular matte.
The Noranda process, as originally designed, allowed the continuous
production of blister copper in a single vessel, by effectively --onsMr-.irig
roasting, smelting and converting into one operation. Metallurgical problems,
however, led to the operation of these reacton for the production of copper
matte. As in flash saeltlng, the Noranda process takes advantage ot the heat
energy available from the copper ore. The remaining thermal energy required
is supplied by oil burners or ay coal mixed with the ore concentrates.
The final step in the production of blister copper is converting. The
purpose of converting is to eliminate the remaining iron and sulfur present
in the "atte, leaving molten "blister" copper. Ml hut one U. S. smelter use
Pierce •••-.with converters, which are refractory lined cylindrical steel shells
mounted on trunnions at either end and rotated about the major axis for
charging and pouring. An opening in the center of the converter functions as
Metallurgical Industry 7,3-3
-------
a mouth, through which molten matte, siliceous flux and scrap copper are
charged and gaseous products are vented. Air or oxygen rich air Is blown
through the molten matte. Iron eulfide (FeS) Is oxidized to Iron oxide (FeO)
and SC>2, and the FeO conbines with the flux to form a slag on the surface.
At the end of this segment of the convor-.er operation, termed the sla# blow,
the s'.ag is skimmed and generally recycled back to the smelting furnace. The
process of charging, blowing and slag skimming in repeated until an adequate
amount of relatively pure Cu2S, called "white metil", accumulates in the
bottom of the converter. A renewed air blast oxidises the remaining copper
sulfide sulfur to S02, leaving blister copper In the converter. The bl.lrteT
copper is subsequently removed and transferred to refining facilities. This
segment of converter operation is termed the finish blow. The SC-2 produced
throughout the operation is vented to pollution control devices.
One smelter uses Hoboken conv^-tiirs, the primary advantage of. which lies
in emission control. The Hoboken converter is essentially like a conventional
Fierce-Smith converter, except that this vessel is fitted with a side flue at
one end shaped as an inverter! U. This flue arrangement permits siphoning of
gases iron the interior of the converter directly to offgss collection,
leaving the converter mouth under a slight vacuum.
Blister copper usually contains from 98.5 to 99.5 percent pure copper.
Impurities may include gold, silver, aitirat'ny, arsenic, bismuth, Iron, lead,
nickel, selcniuir, sulfur, tulliirlur. and ziac. To purify blister copper further,
fire refining and electrolytic refining are used. In fire refining, bliste*:
copper is placed in a fire refining furnace, a flux Is usually added, and
air is blown through the molten mixture to oxidize remaining impurities,
which are removed as a slag. The reneining metal bath is subjected to a
reducing atmosphere to reccnvetL cupTous oxide to copper. Temperature in the
furnace is around 1,100°C (2,010°F). The fire refined coppei is cast into
anodes and further retined electrolytlcally. Electrolytic refining separates
copper t:^."j impurities by electrolysis in a solution containing copper sulfate
and eulfurlc acid. Mttiilllr impurities precipitate from the solution and
form a aludge that is removed and treated to recover precious metals. Copper
is dissolved from ths anode and deposited At the cathode. Cathode copper is
remelted and made into bars, ingot.s or ilabo for marketing purpose. The
copper produced \2 from copper conce.i-
Lrate during roasting or in the volatilization of trace element? as oxide fumes.
Fugitive emissions ^re genercled by l;.aks from major equipment during material
handllrg operations.
RoaJters* smelting furnaces and converters are sources of both pr.rticulate
matter and sulfur oxides, Copper and iron oxides ave th« primary constituents
of the participate matter, bu: other oxides such n'j arsenic, antimony, cadmium,
lead, mercury and zinc may aluo be present, with Metallic sultates and sulfurlc
7.3-A EMISSION FACTORS 1/84
-------
acirt mist. Fuel combustion products also contribute to paniculate emissions
from Toultlhearth roasters and reverberator/ furnaces.
Single stage electrostatic preclpltators (tSP) are widely used In h.he primary
copper industry for the ccntrol of particulate emissions from roasters, smelting
furnaces and converters. Many of the existing ESPs are operated at elevated
temperatures, usually at 200 to 3AOJC (AGO to 6r-OeF) and are termed "hot
ESPs". If properly designed and operated, thess ESPs remove 99 percent or
more of the condensed particulate ma'.ter present In gaseous effluents. However,
at these elevated temperatures, a significant amount of volatile emissions
511.;h a* - rsenic tri-'x'de (Af.^O^) and sulfuiic acid cist Is present as vapor In
the gaseous effluent and Lhua can v.ul l>f collected by the particulate control
device at elevated temperatures. At these temperatures, the arsenic rrloxide
In the vapor state will ptss through an ESP. Therefore, the gas stream to be
troated must be cooled sufficiently to ensure that most of the arseric present
is Condensed before ^ntering the control device for collection. At sc^f%
smelters, the gas effluents are cooled to about 120°C (250°F) temperature
before entering a particulate control system, usually an ESP (termed "cold
ESP"). Spray chambers or air infiltration are used for gas cooling. Fabric
filters can also be used for part.iculate matter collection.
Gas effluents from roasters are usually sent to an ESP or spray chambar/£3P
systeia or art combined with smelter furnace gas effluents before partlculate
collection, Overall, the hoc ESPs remove only 20 to 80 percent of the total
particulate (condensed and vapor) preeenc in the gas. The cold ESPs may
remove more than 95 percent of the total particulate present in the gas.
Particulate collection systems for smelting furnaces are similar to those for
roasters. Reverberatory furnace offgases are usually routed through waste
h.at boilers and low velocity balloon flues to remove., large particles and
heat, then are routed through an ESP or spray chamber/ESP systeia.
In the standard Fierce-Smith converter, flee gases are captured during
the blowing phasp by the primary hood over the converter mouth. To prevent
the hood'a binding to the converter wich splashing molten metal, there is a
gap between the hood and the vessel. During charging and pouring operations,
significant: fugitives may be emitted when the hood is removed to allow
crane access. Converter offgases are treated in ESPs to remove particulate
matter and in sulfuiic acid plants to remove 862.
Remaining sraeltei processes handle material that contains very little
sulfur, hence S02 emissions from these processes are insignificant.
Particulate emissions from fire lefining operations, however, may be of concern.
Electrolytic refining doe^ not produce emissions unless the associated sulfurlc
acid tanks are open to the atmosphere. Crushing and grinding systems used in
ore, tlux tnd sing processing also contribute co fugitive dust problems.
Control of 3C2 emissions from smelter sources is most commonly performed
In a single or double contact sulfurlc acid pls'.nt. Use of a sulfuric acid
plant to treat copper smelter effluent gas streams requires that gas be free
fron particulate matter and that a certain minimum inlet S02 concentration be
main tril ied. Practical limitations have usually restricted sulfuric acid plant
appllc<..lon to gas streams that contain at least 3.0 percent SC^. Table 7.3-1
shows t:ypical average S02 concentrations for the various smelter unit offgases.
;/g; Metallurgical Industry 7.3-S
-------
TABLE 7.J-1. TYPICAL SULFUR DIOXIDE CONCENTRATIONS IN
OFFGASES FROM PRIMARY COPPER SMELTING SOURCES
Unit
lulLiple hearth ruaater
Fluldlxad bed roaaiar
Heva:baratory furnaca
Electric arc furnace
Flaih radllng furnace
C-ntiauoui auditing turnaca
Meree-Salth converter
Hoboken convarter
Single contact H2504 Pl«nt
Doubla contact 87 W^ planr
S^2 concentration
Volume X
1.3
10
0.5
It
10
5
4
0.2
- 3
- 12
- 1.5
- 8
-• 20
- 15
- 7
k
- 0.26
0.05
Currently, converter gas effluents at most of the smelters are treated
for SO2 control In sulfuric acid flatty. Gas effluents from some
-------
TABLE 7,3-2. EMISSION FACTORS FOR PRIMARY COPPER SMELTERS3.b
EMISSION FACTOR RATING: B
fartlculjt e natter
Conf t;,urat Ion*-' Cn , c _
16/10.1 K*/Mg Ib/tLn
v«;
ft
i o 1 1 nw *d by oonvtrt«ra (C)
iMK.ii-th i,«.;ttr (MMKJ
faii.jw«d by rev«it*aratuiy
furnac* (W) .ind convertwifc (C)
jid bed rcaecer (FBR) 'olluwed
by 4l«ccric t urn«cc ( fc "' and
Fluid bed ro4acer (FBR) followed
•>
4
by clercrf c turnace (EF) and!
b/ fj«ih tur-ieice (KFj,
clcaninjg ' u r i a j e (S3) and
oon\-*rt CTB (C)
by Xoranda -taccora 'NR> j:id
xp reused a» ur.lci p«r unit weight
k unit wel^hca 01* concentrate are
C
M*iR
KK
t
KbK
RF
tr
FBR
EF
5St
C*-
NR
C
of coicentr
required to
18
12
2b
Id
25
18
53
IB
NA
50
70
5
no.
NA
NA
a-,d o,
pr^uucf
3f>
>* '}
50
3b
NA
36
10U
36
SA
100
14U
ID
SA
KA
'd prorefiNed by
; t unit weipht
370
J40
90
300
180
Z'O
120
183
0
120
NA
the
of
740
iSO
ISO
600
360
. ^
2*0
820
360
90
.5
NA
aaelter. Appro
blister cupper .
9. 11-1S
4-5, 16-17
".-9. 19-19
8. ;i-13
to
2 I-7"1
IS
20
IS, 23
J-
22
22
uleiatdy
NA -
dvallablc,
hFor parclcjlace mctir reaovil, gneoui effljenti irnn ro«ir»ri, soeltlng fu.njces and canvircera
i.-e uiuilly tr««t*J in ho1: CSPi at 200 - 34D*C ((00 - 633'F) or in cold ESPi with gtiu coaled to
• f-juc ;2C'C (250*F) bafur* CSF, Particulatt eolstlo <« Fro* copper •oelteri contiln volitllt m«t«U:c
u»lde« which regain In vanor loro Jt higher cmperatJ ee and wl.lcn condeno tu nulld pirtlcula:« tc
luwer i eoiparacurea (12C*C or 2504F). Therel'orv, overall parCicvlale removal in hoL CSPa eiiy range
frura 20 - 507, ind overil? partlculite rirao.gl in mid RSPi nay tie 99^. Convattei gaa effluents
and, at auae gnelttra, roaacer get effluent: nr> tr^nreo in single contact acid plant! , iCA.J) sr
double cancacc acid pl.anci (DCAP) for 50j removal. Typical SCAPi are about ?6» efficient, and DCAPs
art jp Ca 99.9 % efficient In 502 reooval. TVi*]r alio rami-we over 99X of partlculate ttattar.
•"In addition to iourcea indlcatad, each aotltar conf Igjriti >n contalnt tin r«f'nlng anode furnicel
aictr the converter*, Ancde furnaces emit nagl^g.'bla S02. No pertlculate enliaion da\La are available
.'or anode Curnecel.
J-
-------
TABLE 7.3-3, FUGITIVE EMISSION FACTORS FOR PRIMARY COPPER SMELTERS3
EMISSION FACTOR RATING: B
Sovrct
rartlculatc matter
Kg/Mg Ib/toi
S02
\b/con
Roasttr calcine discharge
Saelting farn&ce'1
Convert ers
Converter flag return
Anode furnacr
Slftg cleaning furnace^
1.3
0.2
2.2
NA
0,25
4
2.6
0.4
4.4
NA
0.5
8
0.5
2
05
0.05
0.05
3
1
f
no
V.I
0.1
6
"Reference* 16. 22, 25-31. Expressed ai aaau units per unit wulfih'
ot concentrated are (Tocesaed by the nelter. Approilnately '. uu't
welghce of concentrate are required Co produce 1 unit weight o( copper
•etal. Factors for flaeh furnace saeltera and Noranda furnace ««ielt( e
•ay be (lightly lowur than reported value*. NA - not aval lal.le.
^Include* fugitive ealaeloni ii-11 aatce capping and flag Btiaulng
operation*. About 5OX of fugitive parclculece natter eolielsiw and
about 901 of local SO? mission* art fm unrta capping operations,
The remainder li troa aleg nkioalng.
c'J»ed to trtat il/.gs froa aaeltlag furuacei and conva.i.cr'; a': the flash
furnace laialter.
smelting furnace or from leaks, depending upon Che f".mace type and condition.
A typical single matte tapping operation lasts from !> to 10 minutes, ano a
single slag skimming operation loses from 10 to 7.0 mijutes. Tapping frequencies
vary with iurnace capacity and type. In an 8 hour sMft, matte is tapped 5 to
20 times, and sla& is skimmed 10 to 25 times.
Each of the various stages of converter operaticn, the charging, blowing,
slag skimming, blister pouring, and holding, is a potential source of fugitive
enissions. Duvlng blowing, the converter mouth Is In stack (1. e., a close
fitting primavy hood la over the mouth to capture offgases). Fugitive Lzissions
esc<-?p^ from the hoods. During charging, skimming and pouring operations, the
converter mcuth is out of stack (i. e., the converter mouth is rolled our of
its vtrtic,?! position, and the primary hood is isolated). Fugitive emissions
ore discharged during the rollout.
At times during normal smelting operations, slag or blister copper can
net be transferred ^mediately from or to the converters. This condition, the
holdirg stage, may occur for several reasons, Including insufficient mat! e in
the s.>ie It Ing furnace, the unavailability of a crane, and others. Under these
conditions, the converter Is rolled out of vertical petition and remains in a
ho^Mirg position, and fugitive tsnissions may result.
Fugitive -laiasionc from primary copper smelters are captured by applying
cither local or general ventilation techniques. Oace captared, emlssiom may
7.3-8
EMISSION FACTORS
1/84
-------
be vented directly to a collection device or he combined with process otfgases
before collection. Close fitting exhaust hood capture systems are used Cor
mult inearth roasters, and hood ventilation systems for smelter matte tapping
and alag skimming operations. For converters, secondary hood systems ot building
evacuation systems are used.
7.3.A Lead Bmluaion Factors
a\
Both the process and the fugitive particulate matter emissions from
various equl. i<>nt at primary copper smelters coitain oxides of many inorganic
elements, including lead. The lead content of ^articulate matter emissions
depends upon both the lead content of concen-rale feed into the smelter and
the process offgas temperature. Lead emissions are effectively removed in
partlcui'.ate control systems operating at low .tmperaturs} of about 120CC (250°F).
Table 7.3-4 presents lead emission factors for various operations of
primary copper shelters. These omission factors represent totals of both
process and fugitive emiseloi.s.
TABLE 7.3-4. LLAD EMISSION FACTORS FOR PRIMARY COPPER SMELTERS3
EMISSION FACTOR RATING: C
i.ejd
tcg/Hg Ib/ton
0.073 0.15
0.036 0.072
Converting8 0.13 0.27
Refining HA SA
'Reference 32. Expressed an unlta per unit weight of concentrated ore
proceaeed by the «.«elter, Approximately & unit weights 3! concentrate
are required to produce 1 unit weight of copper metal. B*s«d on cess.
data for several smelters containing frcjo O.I to 9.4X lead in fe>*1
throughput. NA - not available.
"For procesa and fugitive enlsalons totals.
cBaaed on teat data on Bult Ihearth roasters. Includes the total uf
proceaa calaaloni and calcine tvanifei fugitive ualaalans. Calcine
tranaftt fugitive ealsalona conatltute about 10 percent of the total of
proctli and fugltlvt aUsslanb.
dBiaad cm teec data on rwtrberatory furnacea. Includea tat.il process
calRtlcnJ and fugitive enlesiona from oatte rapping and alag skimming
operations. fugitive eal»»lon« fron matte tapping and al»n aklniiln^
operatlona aaount to about 3SS ar.4 2Z, respectively.
^Include* the total of protest and fugltlvt taDflont. Fugitive missions
constitute about 30 percent of the total.
1/84 Metali-jrglcal Industry 7.3-9
-------
References for Section 7.3
1. Background Information for New Source Performance Standards; Primary
Copper, Zinc, and Lead Smelters, Volume I, Proposed Standards,
EPA-450/2-74-002a, U. S. Environmental Protection Agency, Research Triangle
Park, NC, October 1974.
2. Arsenic Emissions from Primary Copper Smelters - Background Information
for Proposed Standards, Preliminary Draft, EPA Contract No. 68-02-3060,
Pacific Environmental Services, Durham, NC, February 1981.
3. Background Information Document for Revision of New Source Performance
Standards for Primary Copper Smelters, Draft Chapters 3 through 6, EPA
Contract Number 68-02-3056, Research Triangle Institute, Research Triangle
Park, NC, March 31, 1982.
4. Air Pollution Emission Test; ASARCO Copper Smelter, El faaci, Texaa,
EMB-77-CUS-6, U. S. Environmental Protection Agency, Research Triangle
Park, NC, .June 1977.
5. Written communication fron W. F. Cummins, ASARCO, Inc., El Paso, TX, to
A. E. Vervaert, U. S. Environmental Protection Agency, Research Triangle
Park, NC, August 31, 1977.
6. AP-42 Background Files, Office of Air Quality Planning and Standards,
U. S. Environmental Protection Agency, Research Triangle Park, NC.
7. Source Emissions Survey of Kennecott Copper Corporation, Copper Smelter
Converter Stack Inle and Outlet and Reveiberatory Electrostatic
Precipitator^Jnlet and Outlet, Hurley, New Mexico, File Nurber EA-735-09,
Ecology Audit's, Inc., Dallas, TX, April 1973.
g. Trace Element Study at * Primary Copper Smelter. EPA--600/2-78-065a
and -065b, U. S. Environmental Protection Agency, Research Triangle Park,
NC, March 1978.
9. Systems Study for Control of Emissions, Primary Nonferrous Smelting
Industry. Volume II: Appendices A^and B, PB-184885, National Technical
Information Service, Springfield, VA, June 1969.
10. Design andOperating Parameters Fcr Emission ControlStudies; White
Pine CopperSmelter, EPA-60072-76-036a, U. S. Environments! Protection
Agency, Washington- DC, February 1976.
11. R. M. Statnlck, .Measurement of Sulfur Dioxide, Particulate and Trace
Elements in Copper S.aelter Converter and Roaster/Reverberatory Gas Streams,
PB-238095, National Technical Information Service, Springfield, VA,
October 1974.
1?. AP-42 Background Files, Office of Air Quality Planning and Standards,
U. S. Environmental Protection Agency, Research Triangle Park, NC.
7.3-10 EMISSION FACTORS 1/84
-------
1 3 . Design and Operating Parameters For Emission Control Studies. Kennecott -
McCill Copper Smelter, EPA-600/2-76-036c , U. S. Environmental Protection
Agency, Washington, DC, February 1976.
] 4 . Emibbion Test Report (Acid Plant) of Phelps Dodge Copper Smelter, AJo,
Arizona , EMB-78-CUS-1 1 , U. S. Environmental Protection Agency, Research
Triangle Park, NC, March 1979.
15. S. Dayton, "Inspiration's Deuijjn for Clean Air", Engineering and Mining
Journal , 175:6, Jane 1974.
16. Emission Testing of ASARCO Copper Spelter, Tacoma. Washington, EMB 78-CUS-
12, U. S. Environmental Protection Agency, Research Triangle Park, NC,
ApriJ 1979.
17. Wril.ten conjnunication from A. L. Labbe, ASARCO Inc., Tacoma, WA, to S. T.
Cuffe, U, S. Environmental Protection Agency, Research Triangle Park, NC ,
Novejihar 20, 19?3.
1 8 . jX^ign and Operating Par am eters for Emission Control Studies: ASARCQ -
Ha yd en Copper Smelter. EPA-60U/2-76-036J , U. S. Environmental Protection
Agency, Washington, DC, Febraary 1976.
19. Pacific Environmental Set vices, incorporated, DetiAgn and Operating
Parameters for Emission Control Studies: Kennecott, Hayden Copper
Smelter, EPA-6UQ/2-76-036b, U. S. Environmental Protection Agency,
Washington, DC, February 1976.
20. R. Larkin, Arsenic^ Emissions it Kennecott Copper Corporation, Hnyden^ AZ,
EPA-76-NFS-1, U, S. Environmental Protection Agency, Research Triangle
Park, NC, May 1977,
2 1 . Emission Complianc e Status , Inspiration Consolidated Copper Company ,
inspiration, AZ, U., S. Environmental. Protection Agency, San Francisco,
CA, 1980.
22. Written communication from M. ?. Scanion, Phelps Dodge Corporation, to
D. R. Goodwin, U. S. Environmental Protection Agency, Research Triangle
Park, NC, October 16, 197G.
23, Written f.oraniurii cation fron G. M. McArctiur, The Anaconda Company, to
D. K. Goodwin, U. S. Environmental Protection Agency, Research Trimble
Pirk, NC, June 2, 1977.
24. Telephone communication from V. Katari Pacific Environmental Services.
Inc., Durham, NC, to R. Winslow, Hids.lf;o Smelter, Phelps Dodge
Corporation, Hidalgo, AZ , ApriJ 1,
25. Emission Test Report, Phelps Dodge Copper Sin alter, Douglas^ Ailzona,
EMU-73-CUS-8, U.- S. Environmental Protection Agency, Research Triangle
Park, NC, February 1V79.
/8A Metallurgical Industry 7.3-11
-------
26. EidssloK Testing of Kennecott Copper Smelter, Magna, Utah, EMB-78-CUS-13,
U. S. Environmeatal Protection Agency, Research Triangle Park, NC,
AprU J979.
27. Emission Test Report. Phelps Dodge ..per Snelter, Ajo, Arizona,
EMB-78-CUS-9, U, S. Environmental Protection Agency, Research Triangle
Park, NC, February 1979.
28. Written communication fro-.' P.. L>. Putnam, ASARCO, Inc., to M. 0. Varneri
ASARCG, Inc., Salt Lake City, UT, May 12, 1980.
29. Emission Teat Report, Phelpa Dodge Copper Smelter, Playas, NewMexico,
EMB-78-CUS-10, U. S. Euvir'mav-.ntal Protection Agency, Research Triangle
Park, NC, Marrh 1979.
30. ASARCO Copper Smelter, El Paso. Texas. EMB-78-CUS-7, U. S. Environmental
Protection Agency, Research Triangle Park, NC, April 25, 1978.
31. A. D. Church, et al., "Measurement of Fugitive Particul^.te and Sulfur
Dioxide Emissions at Inco's Coppar Cliff Smelter", Paper A-79-51, The
Metallurgical Society of American Institute of Mining, Metallurgical,
and Petroleum Engineers (AIME), New York, NY.
32. Copper Smelters, Emission Teat ReporL - Lead FjiissloiiH. EMB-79-CUS-14,
1). S. Environmental Protection Agency, Researc.i Triangle Park, NC,
September 1979.
7.J-12 EMISSION FACTORS 1/84
-------
7.4 FERROALLOY PRODUCTION
7.4.1 Process Description1'-1
Ferroalloy is th? generic teini for alloys consisting of iron and -ine or more olhcr imials. Ferroalloys arc used
ir stetl pioduction as alloying elements and deoxidants. There are (bra basic types of ferroalloys: (1)
silicon-based alloys, including feriosilicon and calciu-nsihcon; (2) manganese-based alloys, including fer-
mniiinganese and iilicomanganese; and O) chromium-based alloys, including ferrochromium and fcrrusihcu-
chmme
The four major procedures used io produce ferroalloy and high-purity rneullic additives for iteelniaking a--e:
(I) blast furnace, (2) electrolytic deposition, (J) alumina silico-thermir process, and (-1) electric smelting furnace.
because over 75 percent o( '.he ferroalloys are produced n electric smelting furnaces, this section deals only with
(hat type of funace.
The oldest, simplest ;>nd most widely used electric furnaces are the submerged-arc open type although
semi-covered furnaces are also used. The alloys are made in the electric furnaces by reduction of suitable oxides.
For example, in making ferrochromium the charge may consist of chrome ore, limestone, quartz (silica), t-oal and
wood chip*;, along with scrap iron.
7.4.2 Emissions-*
The production of ferroalloys has many dusi- or fume-producing steps. The dust resulting Irom raw material
handling, mix delivery, and crushing and siring of the solidified product can b«r handled by conventional
techniques am! is orain; rilv not a pollution problem. By far the major pollution [Kohlem arises from the
ferroalloy furrjjc? themselves. The conventional suhtierged-arr furnace utilizes c.i/h.Ni reduction of .netallic
oxides and continuously produces large quantities of carbon monoxide. This sscaoiiv ••!• carrier. Urye quantities
or partitulates ut subm.cron size, making control difficult.
In an open furnace, cssent:ahy aij of tlie carbon nicnoxide buins with indviced air at the top of the charge, and
CO crnissi /ris ire smaJi. ijanicu'atc emissions Irom the open furnace, howevet. can be quitr. large. In the
semi-dose J fur lace, most or all ol thr CO is withdrawn from the furnace and burns with dilution air introduced
into the f.ystem. The 'inburned CO goes through participate control devices and can be used as boiler fuel or eon
be flared directly, Paniculate emission factors for electric smelting fiirnticcs are presented in Table 7.4-1. No
caibon monnxiiJe emission data have been reported in the literature.
2/72 Ylelallurgica! Industry 7.4-1
-------
TABLE 7.4-1. EMISSION FACTORS FOR FERROALLOY PRODUCTION IN
ELECTRIC SMELTING FURNACES*
EMISSION FACTOR RATING: C
Type of furnace and
product
Open furnace
50£ FeSic
752 FeSid
902 FGS1L
Slltcon netal6
Sllicomanganpser
Fer rochrorae-Sllicon
High Carbon ferrochromc
Semi-covered furnace
i-enouar.ganesef
Particulars
kg/Mg
100
157.5
282.5
312.5
97.5
-
-
22.5
Ib/ton
20C
315
565
625
195
-
-
45
Leadb
kg/Mg
0.15
0.0015
-
0.0015
0.0029
0.04
0.17
0.06
Ib/ton
0.29
0.0031
-
0.0 031
0.0057
0.08
0.34
0.11
aEmisslon factors expressed as weight per unit weight of specified
product. Dash Indicates no available data.
bReferences 1-5.
cReference 8.
References 10-11.
^References 9, 12.
^Reference 11.
REFERENCES FOK SECTION 7.4
1. R. A, Pearson, "Control of Emissions from Ferroalloy Fmnace Prjcessing",
presented at the 27th FJectrtc Furnnce Conference, Detroit, MI, December
1969.
2. J. 0. Dealy and A. M. Klllln, Air Pollution Control Engineering .^nd Cost
Study of the Ferroalloy Industry ,~ EPA-450/2-74-008, U.S. Environmental
Protection Agency, Repejrch Triangle Park, NC, May 1974.
3. *. E. i/andergrif t , et al. , Parttculate Pollutant System Study - Mass
Emissions, PB-203-128 , "PB- 203-522 YnT PB"-TO 3-521 , U.S. Environmental
Protection Agency, Researci. Triangle Park, NC, May 1971.
*• Control Techniques for Lead Air Emissions) FFA-450/2 -77-012, U.S. Environ-
mental Profection Agency, Research Triangle Pprk, NC, December 1977.
5. W. !.'. Davis, J:missJ.oj^s_S_tudy of Industrial Sources of Lead Air Pollutants,
l')/a, EPA-APTD-1543", W. E"." "bVvls" and Ascoclates , Leawood", KS, April 1973.
•5. Air Pollutant Enl_s_sinn Factors , Fipsl _Rf P2.rt .- Resources Research, Inc.,
Rcsfrn, VA, [irep.Tred fo- iVatinnr.l Air Pollution Control Administration,
Durham, NC, under Contract Number CPA-22-6S-1 19 , April 1970.
7.4-2 EMISSION FACTORS 12/61
-------
7* tl5.r.''.0>ra,J-AoyB: Stejel '8 All-purpose Additives, The Magazine of Metals
Producing, February 1967.
8, R. A. Parson, Control ofEmifaionp from Ferroalloy Furnace Processing)
Niagara Falls, NY, 1969.
9. Unpublished stack test results, Resources Research, Incorpoiated,
Reston, VA.
10. R. Ferrari, Experiences In Developing an Effective Pollution Control
System for a Submerged-Arc Ferroalloy Furnace Operation, J. Metala,
p. 95-104, April 1958.
11. Fredriksen and Nesr^as, Pollution Prob.lems by Electric Furnace
Ferroalloy Production, United Nations Economic Commission for Europe,
September 1968.
12. R. W. Gerntle and J. L. McGinn!ty, Plant Visit Memorandum, U.S.
DHEW, PHS, National Center for Ait Pollution Control, Cincinnati,
OH, June 1967.
12/Pl MetaUuiTlcal Industry 7 . n-
-------
7.5 IRON AND STEEL PRODUCTION
1-2
7.5.i Process Description and Emissions
Iron ana steel manufacturing nay be grouped in" eight generic process
operations: ]j coke production, 2) sinter production, 31 iron production,
4) steel production, 5) semifinished produLt preparation, 6) finished prod-
uct preparation, 7) heat and electricity supply .-,nd 8) handling and trans-
port of raw, intermediate and waste materials. Figure 7.5-1, a general
flow diagram of the iron and steel industry, interrelates these categories.
Coke production is discussed in detail in Section 7.2 of this publication,
and more information on the handling and transport of materials is found in
Chapter 11.
Sinter Production - The sintering process converts fine raw matv r'vais like
fine iron ^re, coke breeze, fluxstonc, mill scale an-1 flue dust into an 3g-
glomerated product of suitable sije for charging into a blast furnace. The
materials are mixed with water to provide cohesion in a mixing mill and are
placed on a continuous moving grate called the sinter strand. A burner
hood above the front third of the sinter strand ignites the coke in the
mixtuie. Once ignited, combustion is self supporting and provides suffi-
cient heat, 1300 to 1480°C (2i>00 to 2700°F), to cause surface melting and
agglomeration of the mix. On the underside of the sinter machine lie wind-
boxes that draw the combusted air through the material bed into a common
duct to a pa.ticulate control device. The fused sinter is discharged at
the end of the sinter machine, where it is crushed and screened, jnd any
underside portion is recycled to the inixi, ; nill. The remaining sinter is
cooled in open air by water spray or by mechanical fan to draw off the he.it
from the sinter. The cooled sinter is screened a final time, with the
fines being recycled and the re-,t being sent to charge the blast furnaces.
Emissions occur at sevrral points in the sintering process. Points of
particulate generation are the windbox, the discharge (sinter crusher and
hot screen), the cooler and ihe cold screen. In audition, inplant. transfer
stations generate emi^.irns which can ^e controlled by local en-: losures.
All the abovp sources except the coolrr normally are vented to one or two
control systems.
Iron Production - Iron is produced in blost furnaces, which are large ie-
fractory lined chbuiberb i"to which iron (as natural ore or as agglomerate"1
products such as pellets o. sinter, coke and limestone) is charged and al-
lowed to r^act with large amounts of hot air to produce molten iron. Slag
and blast furnace gases are byproducts ot this operation. The average
charge to produce one unit weight of iron requires 1.7 unit weights of iron
bearing charge, 0.55 unit weights of coke, 0 2 unit weights of limestone,
and 1.9 unit weights of air. Average blast furnace byproducts consist of
0.3 unit weights of slag, 0.05 unit weights of flue dust, aud 3.0 unit
weights of gas pr-r unit of iron produced. The flue dust and other iron ore
fines from the process .:re ^onverte^ into useful blast furnace charge by
the sintering operation.
5/33 Metallurgical Industry 7.5-1
-------
in
3
n
3
•
Figure 7.J-1. General flow aiagrara for the iron and stee1 Industry.
Ln
oc
-------
Because ot its high carbon monoxide content, this blast furnace gas
has a low heating value, about 2790 to 3350 joules per cubic liter (75 to
90 BTU/ft3) and is us',-d as a fuel within the steel plant. Before it can be
efficiently oxidized, however, the gas must be cleaned of particulate.
Initially, the gzses pass through a settling chamber or dry cyclone to re-
move about 60 percent of the particulate. Next, the gases undergo a one or
two stage cleaning operatio:.. The primary cleaner is normally a wet scrub-
ber, which remover, about" 'jii percent cf the regaining pairticulate. The sec-
ondary cleaner is -. high energy wet scrubber (usually a venturi) or au
electrostatic precipitato-, either of which can remove up to 90 percent of
the partii:ul";.te that elides the primary cleaner. Together these control
devices provide a clean fuel of less than 0.05 grams pci cubic meter (0.02
gr/ft3) fr>r use in the steel plant.
Emissions occur during the production of iron when there is a blast
furnace "slip" and daring hot metal transfer operations in the cast house.
All gas generated in the blast furnace i^ normally cleaned and used for
fuel. Conditions such as "slips", however, can cause instant emissions of
carbon monoxide and particulates. Slips occur when a stratum of the mate-
rial charged to a blast furnace does not settle with the material below it,
thus leaving a gas filled space Between the two portions of the charge.
When this unsettled stratum of charge collapses, .-he displaced gas may
cause the top gas pressure to increase above the safety limit, thus opening
a counter weighted bleeder valve ^o the atmosphere.
Steel Production (Basic Oxygen Furnace) - The basic oxygen process is used
to produce steel from a furnace charge typically composed of 70 percent
molten blast furnace metal and 30 percent scrap metal by use of a strean: of
commercially pure oxygen to oxidize the impurities, principally carbon and
silicon. Most of the basic oxygen furnaces (EOF) in the United States have
oxygen blown through a lance in the top of the furnace. However, the
Quelle Basic Oxygen PTOCCFS (QBOP), which is growing in use, has oxygen
blown through tuyeres in the bottom of th<= fnrn.Tf-p. Cycle times for the
basic oxygen process range from 25 to 45 minutes.
The large quantities of carbon monoxide CCO) produced by the reactions
in the RGF can be combusted at the mouth of the furnace and then vr-nted to
gas cleaning devic«r;, as with open hoods, or the combustion, can be. sup-
pressed at the furnace mouth, as wiih closed hoods. The term "closed hood"
is actually a misnomer, since the opening at the furnace mouth is large
enough to allow approximately 10 percent ol theoretical air to enter. Al-
though most furnares installed before 1975 arp of th< open hood design,
nearly all the QBOPs in the United States have closed hoods, and most of
the new top blown furr.aces are being designed with closed hoods.
There are. several sources of emissions in the basic oxygen furnace
steel making process, 1) the furnace mouth during refining •• with collec-
tion by local full (open) or c.ippressed (closed) combustion hoods, 2) hot
meta] transfer to cha.-ging ladle, 3) charging scrap and hou metal, 4) dump-
ing clag and 5) tapping steel.
Stetl Production (Electric Arc Furnacer.) - Electiic arc furnaces (EAF) ar.-1
used to produce carbon and allny steels. The charge to an RAF is nearly
5/f}3 Metallurgy cj 1 Industry 7.5-3
-------
always 100 percent scrap. Direct arc electrodes through the rocf of the
furnace melt the scrap. An oxygen lance may or nay not be used to speed
the melting and refining process. Cycles range from 1-1/2 to 5 hours for
carbon s;teel and from 5 • o 10 hours, for alloy steel.
Sources of eijiissiuiic in the electric art furnace steel making process
are 1) emissions liom melting ^nd refining, often vc.ited through a hole in
th1? furnace roof, 2) charging scrap, 3) dumping slag and 4) tapping steel
In interpreting and using emission frctors for EAFs, it is important to
know what configuration one is dealing with. For example, if an EAT has a
building evacuation system, the emission factor before the control device
would represent all melting, refining, charging, tapping and slagging emis-
sions which ascend to the building vcuf. ^oference 2 has more details OP
various configurations used to control electric arc furnaces.
Steel Production (Open Hearth Furnaces) - In *he open heartn furnace (OHF),
.1 mixture or iron aiid steel scrap and hot metal (molten iron) ;s melted in
a shallow rectangular basin or "hearth". Burners producing a flame above
the charge provide the heat necessary for melting. The mixture of scrap
and hot metal can vary fron all scrap to all hot metal, but a half and half
mixture is a reasonable industry average. The process may or may not be
oxygen lanred, with process cycle times approximately 8 hours and 10 h^urs,
respectively.
Sources of emissions in the open hearth furnace steel making process
are 1) transferring hot metal, 2) melting and refining the heat, 3) charg-
ing of .scrap and/or hat metal, 4) dumping slag and 5) tapping steel.
Semifinished Product Preparation - Aiter '-he steel has been tapped, the
irolten metal is teemed into ingots which are later heated to form blooms,
billets or slabs. (In a continuous casting operation, the molten metal may
bypass ;his entire process.) The product next goes through a process of
surface preparation of semifinisht-d steel (scarfingj . A scarfing machine
removes surface defects before shaping or rolling of the steel billets,
blooms and slabs by applying jets of oxygen to the surface of the steel,
which is dt orange heat, thus removing a thin layer of the metal by rapid
oxidation. Scarfing can be performed by marhine on hot semifinished steel
or by hand on cold or sl'ghtly heate 1 semifinished steel. Emissions occur
during teer.iing as the molten metal is poured, and when the semifinished
steel products are manually or machine scarfed to remove surface defects.
Miscellaneous Combustion Sources - Iron and steel plants require energy
(heat or electricity.) for every plant operation. Some energy operations on
plant property that produce emissions are boilers, soaking pits and slab
furnaces which burn coal, No. 2 fuel oil, natural gas, coke oven gas or
blast furnace gas. In soaking pits, ingots are heated until the tempera-
ture distribution over the cross sectior of the ingots is acceptable and
the surf/ice temperature is uniform for further rolling into sei.ufinished
products (blooms, billets and slabs). In slab furnaces, a slab is heated
before being rolled into finished products (plates, sheets or strips). The
emissions from the combustion if natural gas, fuel oil or coal for boilers
7.5-4 EMISSION FACTORS 5/83
-------
can be found in Chapter 1 of this docujnent. Estimated emissions from these
same fuels used in soaking pits or sl.ib furnares can be the same as those
for bo-.lers, but since it is estimation, the factor rating drops to D.
Emission factor data for Mast furnace gas and coke over, gas are not
available and must be estimated. There are three facts available for mak-
ing the estimation. First, the gas exiting the blast furnace passes
through primary and sec ndary cleaners and can be cleaned to less than 0.05
grams per cubic meter (0.02 gr/ft3). Second, nearly one third ot the coke
oven ^as is methane. Third, there are no blast furnace gas constituents
that generate particulate when burned. The combustible constituent of
blast furnace gas is CO, which burns clean. Based on facts one and three,
the emission factor for combustion of blast furnace gas is equal to the
paniculate loading of that fuel, 0.05 giams per cubic meter (2.9 lb/106
ft3).
Emissions for combustion of coke oven gas can be estimated in the same
fashion. Assume that cleaned coke oven p,as has as much particulate as
cleaned blast furnace gas. Since one third of the coke oven gas is meth-
ane, the main component of natural gas, it is assumed that the combustion
of this methane in coke oven gas generates 0.06 grams oer cubic mete> (3.3
lb/106 ft3) of particulate. Thus, the emission factor for the combustion
of coke oven gas is the sum of the particulate loading and that generated
by Lhe methane combustion, or 0.1 grams per cubic n.eter (6.2 lb/106 ft3).
Open Dust Sources - Like process emissio. -ources, open dust sources con-
tribute to the atmospheric particul^te burden. Open 'list sources include
1) vehicle traffic on paved and unpaved roads, 2) raw material handling
outside of buildings and 3) wind erosion from storage piles and exposed
terrain. Vehicle traffic consists of plant personnel and visitor vehicles;
plant service vehicles; and trucks handling raw materials, plant deliver-
ables, steel products and waste materials. Raw materials are handled by
clamshell buckets, bucket/Ladder conveyors, rotary railroad dumps, bottom
railroad dumps, front end loaders, truck dumps, and conveyor transfer sta-
tions, all of which disturb the raw material and expose fines to the wind.
Even fine materials resting or flat arjas or in storage piles are expot.ed
and are subject to wind erosion. It is not unusual to have several million
tons of taw materials stored at a plant and to have in t.hc range of 10 to
100 acres of exposed area there.
Open dust source emission factors for iron and stoel production are
presented in Table 7.5-1. These factors were determined through source
testing at various in'Pgratcu irod and sceel plants.
As an Alternative to the single valued open dust emission factors
given in Table 7.5-1, empirically derived (mission factor equations are
presented in Chapter 11 of this -locument. Each equation was developed for
a source operation defined on the basis of a single dust generating mecha-
nism which crosses industry lines, such as vehicle traffic on unpaved
roads. The predictive equation explains much of the observed variance in
measured emission factors by relating emissions r.o parameters which charac-
terize source conditions. These parameters may bi? grouped into three cate-
gories: 1) measures of source artivity or energy expended (e.g., the speed
5/83 Metallurgical Industry 7.5-5
-------
TABLE 7.5-1. IJNCONTROLLLD PARTICULATE EMISSION FACTORS FOR
OPEi; DUST SOURCES AT IRON AND STEEL MILLS3
Ope rat LOB
CoQt xouc lit drop
iiatei
Pile formation -
itacker
Pellet ortc
c
Coal"
Batch drop
Front eod loader/truckc
Ui|h lilt ilag
Lou eilt >l»g
Vehicle i.-»?«l OQ
uopavrd roadt .
Light duty vehicle
tediuai duty vehicle
Heavy duty vehicle
Vehicle travel oo
paved raada
Ligbt/heavy vehicle •nc
.. sented in Chipirr 11.
Eaieaioiki by pajrticlv
< 30 >•
;j
o. :zb
1.2
0.0024
0.15
0.30C30
O.ObS
0.00011
13
0.026
4.4
0.008B
0.51
i.a
2.1
7.3
3.5
l( Mieritl tremferred.
Jj 3efereace j. loterpclit..
»a IP other
R*fec«nci 4. Interpolit.oo LO other
< 15 >JB1
9.0
3.018
0.75
O.OOIS
0 095
0.00019
0.034
0.000(169
S.5
3.017
2.9
a.005 a
3.37
1.3
1.5
J.J
2.7
9.7
D 16
0.56
lize iao
<• 10 M
6.5
0.013
0.5i
0.0011
0.075
0.00015
0.026
•e faerodyuaaic
• < 5 M>
• .1
1.0084
'..02
1 . 0006fc
( . Q4| J
i oojoei
t 914
0.000052 1 000029
6.5
0.013
2.2
0.0043
C.2B
i.O
1.2
4.1
2.1
7 6
0.12
0.44
'.0
( OOflO
1 . 4
'. .0029
0.18
3.64
O./J
2.5
1.4
4.8
0.079
0 28
11 J
B > P
Units/unit of
pirticle sizes
particle size*
ciitaoce
will be
-.11 be
triveler .
ippromate
dpproxiDaie.
diaawCer )
< 2.5 urn
2.3
0 .0046
0.17
O.J0034
0.022
0.000043
3.3075
3.300015
2.3
3.0046
3.10
J.ODI6
3.10
0.37
D.42
1.5
0.76
2.7
0.042
0-13
.
Uoici
*"1|
ID/T
e/lj
ib/T
I./-H
Ib/T
ij/Mj
tb/T
I/MI
lb/T
R/1|
Ib/T
k|/VKT
Ib/VMT
k|/VKT
Ib/VHT
kg/VTT
Ib^VMT
kJ/VKT
It/VMT
nitsioci,
Factor
Rating
U
D
B
B
C
C
E
E
C
C
c
c
c
c
c
c
a
a
c
c
_
ar
and weignt of a vehicle traveling on an unpaved road), 2] properties of t'ie
material being disturbed (e.g., the cun'ent of suspendible fines in t!iK
surface material on an unpaved road) and 3) climatic parameters (e.g., num-
ber of precipitation free d.iys per year, when emissions tend to a maximum).
Berau.l,e the predirtivr equations allow for emission facie:: adjustment
to specific source conditions, the equations should be used in ^lace of the
factors in Table 7.5-1, if emission estimates for sources in a specific
iron and steel facility are needed. However, the generally big.her quality
rat'.ngs assigned to the equations are applicable only if 1) reliable values
of correction parameters have been determined for the specific sources of
interest and 2) the corrtA.tion parameter values lie within the ranges
r.ested in developing the equations. Chapter 11 lists measured properties
of aggregate process materials and road surface materials in the iron and
stee'j. industry, which can be used to estimate correction parameter values
for the predictive emission factor equations, in the event that site spe-
cific values are not available. Uso nt mean correction parameter values
from Chapter 11 reduces the qaal;ty ratings, of the emission factor equation
by one level.
7.5-6
EMISSION FACTORS
5/83
-------
Participate emission factors for iron and steel plant processes are in
Table 7.5-2. These emission factors are a result of an extensive in/esti-
^ation by EPA and the American Iron and Steel Institute.2 Carbon monoxide
emission factors are in Table 7.5-3.5
TABLE 7.5-2. PARTICIPATE EMISSION FACTORS FOR IRON AND STEEL iITLLS3
'»«•
Blaat luraacei
Slipi
Uncontrolled caat houae eajlitioni
HoBitor
lap bole and .rough (not runnera)
Sic tu vag
Vicdboi eaiiaiioDi
Uncontrolled
L*i iog grit*
After cetrae paniculate removal
CoDtrolled by dry U?
Controlled by vet ISP
Controlled hy (crabber
Co>irol\ed toy cyclone
Sinter dieciurgt (breaker and hot
icrtent)
Uncontrolled
Controlled by bagbeuie
Controlled by orifici acrubber
Vindboi and ducbarge
Controlled by bagbauie
Baiic oxyeta furnactt
Top tlewn furnace •eiLing and refii.xng
Uncontrolled
Controlled by open hoed »enttd to:
ESP
Scrubber
CoBlrollcd by doted bood veoted to:
Scrubber
QBCP aielting and refiniag
Coclrclled by acrubbt-
Charging
At aource
At building Booitor
Tapping
At aource
At building Bonilcr
Hot Beta? trinrfer
At aource
At building Boaitcr
EOF ftoEitor (all lour.-ll)
Electric arc lurnacea
Helting and refining
Vi. control led
Car be. iteel
Cbarging, tapjuog aod iliggiag
Uncontrolled efliinoaa eacaping
axinittr
Mrltinj, refining, rharging, lapping
and "lagging
Lneontrolltd
A! ley ite iteel)
Configuration 2
(DSE plui clurgxnt liood veoteJ
to COWOD bagbouie ior carbon
ateel)
Unit!
kg (ItO/illp
kg/Kg (Ib/ton) bot rni\
kg/Sg (Ib/ten) riniib«d
ainter
kg /rig (Ib/teo) finiahed
•inter
kg/Hg (Ib/ton) finiahed
•intar
kg/«j fill/tool atcel
»g/1g (Ib/lonJ ateel
»l,/Mg (Ib/ton) uot ertjl
•I/Ng (Ib/ton) atctl
kg/.lg (Ib/tco) hot m*t.ii
kl/!1g (lb/tob) iteel
kg/Hg (Ib/ton) atccl
k^/Hg (Ib'toc) ate«l
kg/Kg Ub/lon) alee:
Eaiitl
39.5
0.3
C.15
5. Si
4.35
0.8
0.08S
0.135
O.S
3.4
C.PS
O.J95
0.15
14.25
0.065
0 045
0.0034
0.026
0.1
0 O'l
P. 46
C.14S
0 . 09^
0 028
0.25
19
0 7
5.65
25
0.15
O.C215
iona Ian a 1 100 Tarter
Rating
(87)
(O.i)
(0.3)
(11.1)
'I.?)
a. 6)
(0.17)
(0.47)
(1)
(b.«)
(0.1)
it.:?'
(0.3)
(IB. 5)
(0.1J)
(0 09)
(0 0066)
(0.0i6)
(O.fc)
(0.142.
(0
-------
TABLE 7.5-2. PART1CULATE EMISSION FACTORS FOR IRON AND
STEE!. MILLSa (contirueu)
Source
Uoitl
EauluoQ Factor
OpdD bea~Lk fiinutce*
Heltinr. and refining kg/Hg (Ib/ton) neel
wiveorLi >1 .ej
C. t si ltd by ESP
Roof ascriior •uiiaalona
Leaded itael »»/hl (Ib/Kin! nLecl
UncantrMlro (aa ••I'ured at the
•ource?
Controlled by aide draft hood vented
tj baghoute
Unloaded ai.ce!
aourc'.')
Control .'eri by aide draft hood •anted
to b' iibouie
Ha-h..ia icarfing
JuconLr illed kg/N| (Ib/ton) aetal
through icarfer
Caetrollad by E9F
^
Boii.rt, aoakini |>iLa and t iab rehaat k|/10B J (lb/10* BTU)
furnacca
Ilait furnace gaa
Coke oven gaa
fc Rtlarencc 2. ESP « alsclroatatic precipllalur . D5E * dirtcl
For fuela Burn a* coal, fuel oil and natural gaa, uie *be eat
10.
0
0.
D,
C.
Q
0.
0
0.
0
0
•bell n
51
14
OS*,
<-33
.001!
D1S
. V JJ
.0008
.05
.0119
.015
.0052
ratuai
••iou factcr.
(21
(0
(0
(0
(C
°
(0
(0
(0
(0
(0
L.1CH
1 )
.28)
.168)
.81)
.0038)
'
.0016)
.1)
.023)
.033)
.012)
.
preaented ID Cu
A
A
C
A
A
A
B
A
E
D
.autvr 1 of
thii doruoeDt. Tlf factor ruing for iheit fueli in boileri 1» A, «nd in aoaklng piti and ilit re-
beat furoacet II C
TABLE 7.5-3. UNCONTROLLED CARBON MONOXIDE
EMICSiON FACTORS FOR IRON
AND SIFEL MTLI.S3
EMISSION FACTOR RATING: C
Source
, Reference 5.
Ib/ton
Sintering windhox
Basic oxygen furnace
Electric arc furnace
2;:
69
9
,4
138
18
Expressed as units of emissions per uriit
of finished sinter.
7.5-8
EMISSION FACTORS
5/33
-------
References for Section 7.5
1. H. E. McGannon, ed., The Making, Shaping and Treating of Steel, U. S.
Steel Corporation, Pittsburgh ,~ PA, 1971.
2. T. A. Cuscino, Jr., Participate Emission Factors Applicable to the
Iron and Steel Industry, EPA-450/4-79-029, ~U. S. Environmental Protec-
tion Agency, Research Triangle Park, NC, September 1979.
3. R. Bohn, et al. , Fugitive_Emissions from Integrated Iron and Steel
Plants, EPA-600/2-78-050, U. S. Environmental Protection Agency,
Research Triangle Park, NC, March 1978.
4. C. Cowherd, Jr., et aj., Iron and Steel Plant Open bource Fugitive
Emission Evaluation, EPA-600/2-79-103, U. S. Environmental Protection
Agency, Research Triangle Park, NC, May 1979.
5. Contro1 Techniques for Carbon Monoxide Emissions from Stationary
Sources, AP-65, U. S. Department of Health, Education and Welfare,
Washington, DC, March 1970.
5/83 MeLallurgieral Industry 7.5-9
-------
7.6 PRIMARY LEAD SIIELTING
1-3
7.6.1 Process Description
Lead is usually found naturally as a sulfide pra containing small
amounts of copper, iron, zinc and other trace elements. It is normally
concentrated at the mine from an ore c"iyo: belt moved by gears and sprockets. Each
pallet consists of perforated or slotted grates, beneath which are
windboxes connected to fans that provide 3. draft through the moving
sinter charge. Depending on the direction of this draft, the sinter
machine is either of the updrafl or downdraft type. Except for the
draft direction, however, all machines are similar in design,
construction and operation.
Tl.e sintering reaction is autogenous, occuring at a temperature of
approximately 180CTF (1000°C):
2PbS + 302 •* 2PbO + 2S02 (D
Operating experience has shown that system operation and product quality
are optimum when the sulfur ronter.t ot the sinter charge is between 5
and 7 percent by weight. To maintain this deslrsd sulfur content,
sulfide-free fluxes such as silica and limtstone, plus larga amounts of
recycled sinter and smelter residues, are added to the mix. The quality
of the product sinter is usually determined by its Rdttar Index hardness,
which is inversely proportional to the sulfur content. Hard quality
sinter (low sulfur content) is preferred, because it resists crushing
during dischaige from the sinter machine. Undersized sinter usually
results from insufficient desulfurlzation and is recyclea for further
processing.
2/JiO MHulhirfiiriil lmlii>lr\ , .(>• I
-------
Of che two kinds of sintering machines used, the updrarr. design is
superior for many reasons. First, the sinter bed thickness is more
permeable (and hence can be larger), thereby permitting a hig'ier pro-
duction rate than that of a downdraft machine of t-imilar dimensions.
Secondly, the small amounts of elemental lead that form during sintering
will fjolldlfy at their point of formation in updraft machines, whereas,
in downdraft operation, the metal tends to flow downward and collect on
the grates or rt the bottom of the sinter charge, thus causing increased
pressure rjrop and attendant reduced blower capacity. In addition, the
updraft system exhibits the capability of producing sinte^ of higher
lead content and requires less maintenance than the downdraft machine.
Finally, and most important fro-a an air pollution control standpoint,
updrafr slnterlrig can produce a single strong S02 etfluent stream from
the operation, by use of weak gas recirculation. This, in turn, permits
more efficient and economical use of control methods such ?s sulfuric
acid recovery devices.
7.6.1.2 Reduction - Lead reduction is carried out in a blast furnace,
basically a water Jacketed shaft furnace supported by a refractory base.
Tuyeres, through which combustion air is admitted under pressure, are
located near the bottom and £• C02 CO
C + C02 •+ 2CO (4)
2PbC) + rbS -> 3Pb + S02 (5)
PbSO, + PbS •+ 2Pb -t- 2S30 (6)
•4 /
Carbon monoxide and heat required fcr reduction aif supplied by the
combustion of coke. Most of the impurities are eliminated in the slag.
Solid products from the blast furnace generally separate into four
layers: speiss, the lightest mater!."1-! (basically arsenic and ar.timuny) ,
matte (copper sulfide and other met^J sulflnns), slag (primarily
silicates), ;.-"i load bullion. Tne first three layers are combined as
slag, which is continually collected frnni the furr.acp. and either processed
an the amelter for its metal content ur shipped to treatment facilities.
EMISSION F.vrnns 2/»o
-------
Sulfur oxides are also generated in blast furnaces from small
quantities sf residual lead sulfide and lead sulfates in the sinter
feed. The quantity of these emissions is a function not only of the
residual sulfur content in the sinter, but also of the amo-mt of sulfur
that is captured by copper and other impurities in the slag.
Ruugh lead bullion from the blast furnace usually requires pre-
liminary treatment (dressing) in kettles before undergoing refining
operations. First, the bullion is cooled to 700 to SOOT (370 - 430°C).
Copper and small amounts of sulfur, arsenic, antimony and nickel are
removed from solution> collecting on the surfare as a dross. This
diu^r., <" turn, is treated in a reverberatory furnace whera the copper
and other metal impurities are further concentrated before being routed
to copper smelters for their eventual racovery. Crossed lead bullion is
treated for further copper removal by the addition of sulfurbearing
material and zinc, and/or aluminum, to lower the copper content to
approximately 0.01 percent.
7.6.1.3 Refining - The third and final phase of smelting, the refining
of the bullion in cast iron kettles, occurs in five steps:
- Removal of antimony, tin and arsenic.
- Removal of precious metals by Farke's Process, in which zinc
combines with gold and silver to form an insoluble intermetallic at
operating temperatures.
- Vacuum removal of zirc.
- Removal of bismuth using the Betterson Process, which is the
addition of calcium and magnesium to form an insoluble co.r.prmnd
with the bisifuth t.hat is skimmed from ti:e kettle.
- Removal of remaining traces.of metal impurities by addition
of NaOH and NaX03.
The final refineo lead, commonly of 99.990 to 99.999 percent purity,
is then cast into 100 pound pigs for shipment.
12
7.6.2 Emissions and Cuntrols '
Each of the three major lead smelting process steps generates
substantial quantities of particulates and/or sulfur dio::ide.
Nearly 85 percent of the sulfui prisent in the lead ore r.oncentrate
is eliminated in the sintering operation. In handling process jffgases,
either a single weak stream is taken from the mnchine hood ar less than
2 percent SO?, or two streams are taken, one strong stream (5-7
percent S02) irom the feed end of the machine and or.e weak -stream (<0.5
percent SO?) from the discharge end. Single stream operation has been
T.ft-H
-------
used when there is little or no market for recovsred sulfur, 30 that the un-
controlled weak SO2 stream is emitted to the atmosphere. WKjn sulfur romovil
is required, however, dual stream operation Is preferred. The strong stream
is sent to a sulfuric acid plant, and the weak stream is Dented to the atmos-
phere after removal of particulares.
TABLE 7.6-1.
EMISSION FACTORS FOR PRIMARY LEAD SMELTING
PROCESSES WITHOUT CONTROLS3
EMISSION FACTOX RATING: B
Process
Ore crushing15
Slntorlng (updraft)f
Tnt;il
kg/",^; lh/tun
' .0 2.0
106.5 211.0
Sulfur dioxide
Vg/Mg lb/ton
-
2/5." 550. U
k*/M8
0. 15
87
(4.2-170)
lead
lb/ton
0.3
174
(8.4-340)
BJast furaac«d
Dross reverberauory
furnace*
Material* handling'
180.5
10.n
2.5
361.0
20 0
5.0
22.5
Neg
45.0 29 59
(8.7-50) (17.5-100)
Ncg
2.4
(1.3-3.5)
4.8
(2.6-7.0)
aOre crushing emission laccor.s expressed as kg/Mg Clb/ton of crusheJ ore. All othvr
ealBslon factors expressed as kg/MR (lb/t^n) of lead product. Dash Indicates no
available data.
References 2, 13.
^References 1, 4-6, 11, 14-17, 21-22.
dReference* 1-2, 7, 12, 14, 16-17, 19.
eReferences 2, 11-12, 14. 18. 20.
2.
When dual gas stream opera'Clou is used with updraft sinter machines, the
weak gas sUcim can be recirculated through the bed to mix with the strcng gas
stream, resulting in a single stream with an S02 concentration of abou: 6 per-
cent. This technique has the overall effect of decreasing machine prsducllon
capacity, but permits a raore convenient ml economical recovery of Che S02
by sulfuric acid plants and other control methods.
Without weak gas reclrculatlon, the latter f/orfi.; . of the sirrer machine
a:t9 as a cooling zone for the sinter and t consequently, assists in rhe reduc-
tion of dust farmatlon during product discharge and screening. However,
t;hen recirculation ia user1, the sinter is usually discharged in a relatively
hot state, 400 - 500° C (745 co 9 "in0?), with an attendant increase n partic-
ulates. Methods for reducing these dust quantities include recirculation of
cnfgases through the sinter bed, relying upon the filtering effect of the
bed or the ducting of gases fiorn the discharge through a particulate collection
il^vic:e and then to the atmosphere. Because reaction activity has ceased In
the discharge area, these latter gases conto.in little S02-
7. C.-
EMISSION FACTORS
12/81
-------
Tie particuLate emissions from sinter machines range from 5 to 20
percent of the concentrated ore t'e^d. When expressed in terms of
product weight, a typical emission is estimated to be 213 Ib/ton (106.5
kg/MT) of lead produced. This -,alue, along with other particulate and
S02 factors, appears in Table /.6-1.
Table 7.6-2. PARTICLE SIZE DISTRIBUTION OF HUE DUST
FROM UPDRAFT SINTERING MACHINES
Size
20 -
10 -
5 -
(pro)
40
20
10
i
Percent by weight
15 - 45
9-30
4-19
1-10
Typical material balances from domestic lead smolters indicate that
about 15 percent of the sulfur in the ore concentrate fed to the sinter
machine is eliminated in the blast furnact. However, only half of this
amount (about 7 percent of the total sulfur in the ore) is emitted AS
S(>2. The remainder is captured by the slag. The concentration of this
S02 stream can vary from 500 to 2500 ppm, by volume (1.4 - 7.2 g/m3),
depending on the amount of dilution air injected to oxidize the carbon
monoxide and to cool the stream before baghouse particulate removal.
Partioulate emissions from blast furnaces contain many different
kinds of material, including a range of lead oxirtes, quartz, limestone,
iron pyrites, Iron-lime-silicate slag, arsenic, and other metal-containing
compounds associated with lead ores. These particles readily agglom-
erate and are primarily submicron in size, difficult to wet, aad cohesive.
They will bridge and arch in hoppers. On the avenge, this dust loading
is quitt substantial (see Table 7.6-1).
Virtually no sulfur dioxide emissions are associated with the
various refining operations. However, a smali amount of particulate is
generated by the dross revcvheratory furnace, abcut 20 Ib/ton (10 kg/FT)
cf lead.
Finally, minor quantities of particulates are. ;2-?nerated by ore
crusning and materials handling operations. The; j ^mission factors are
also presented in Table 7.6-1.
Table 7.6-2 is a listing of size distributions of flue dust from
updraft sintering machine efflue.it. Though th^se are not fugitive
emissions, the size distributions :nay closely resemble those of the
fugitive emissions. Particulate fugitive emissions from the blast
furnace consist basically nf lead oxide.s, 92 percent of which are less
than 4 yn in size. Uncontrolled emissions from a lead dross revo.r-
beratory jurnace a^c irostly less than 1 urn, and this may also be the
case with the fugitive emissions.
2/liO MrlJillnrfiiral Inilnslrv 7,(» ">
-------
Table 7.6-3.
EFFICIENCIES OF REPRESENTATIVE CONTROL DEVICES USED WITH
PRIMARY LEAD SMELTING OPERATIONS
•J.
X
30
'f.
Control method
a
Centrifugal collector
Electrostatic precipitator
Fabric flltera
Tub ilar cooler (associated with waste heat boiler)
Sulfuric acid plan; (single contact) '
Sulfuric acid plant (dual contact) '
Elemental sulfur recovery plant '
Dimethylaniline (DMA) absorption process '"
b,f
Ammonia absorption process
Reference 2.
Reference 1.
Efficiency range^ 7.
Particulates Svlfur dioxide
80 to 90
95 to 99
95 to 99
70 to 80
99.5 to 99.9 96 to 97
99.5 to 99.9 96 to 99.9
90
95 to 99
92 to 95
inlet concentrations of 5-7£ typical outlet emissioi levels are 2000 ppm (5.7 g/m31 for single
contact and 500 ppm (1 4 g/m3) for dual contact.
Collection efficiency for a two stage uncontrolled Glaus type plant. Refer to Section 5.IS r-^r more
infon?.' tion.
Based on 30v inlet concentrations of A-6/.', typical outlet emission levels range from
500-3000 ppir U.4-8.6 g/m3).
Baseii on S02 inlet concentrations of 1.5-2.5%, typical cutset emission level 1:-
120C pptn (3.A g/m3).
tc
-------
Table 7.6-4. POTENTIAL FUGITIVE EWISSTON FACTORS FOR PRIMARY
LEAD SMELTING PROCESSES WITHOUT CONTROLS8'b
EMISSION FACTOR RATING: E
Pai titillates
Process Ib/ton kg/MT
Ore rolxli-i; and palletizing (crushing) 2.26 1.13
Car charging (conveyor loading and
transfer) of sinter 0.50 0.25
Sinter machine leakage0 0.68 0.34
Sinter return handling 9.00 4.50
Sinter machine dischnrge, sinte.- crushing
and screening0 1.50 0.75
Sinter transfer to dump area 0.20 0.10
Sinter product dump area 0.01 0.005
Blast furnac-a (charging, blov. condition,
tapping) 0.16 0.08
Lead pouring to ladle, transferring, and
slag pouring 0.93 0.47
Slag cooling6 0.47 0.?.4
Zinc fuming furnace vencs 4.60 2.30
Dross kettle 0.48 0.24
Reverberatory furnace leakage 3.00 1.50
Silver retort building 1.80 0.90
Lead casting 0. 87 Q.4-'.
a All factors are expressed in units per end product lead produced,
except sinter operations, which are expressed in units per sinter or
sirter handled/transferred/charged.
Refer'-nrt. fl, except where ncKed.
References 9 and 10. Engineering judgement using steel sinter machine
'.f-ailr\
-------
Emission controls on lead smelter operations are for particulates
and sulfur dioxide. The most commonly employed high efficiency pani-
culate cor.".rol devices oxre fabric fiJters and electrostatic prec:ip-
itators, which often follow centrifugal collectors and tubular coolers
(pseudogrnvity collectors). Three of the 6 lead smelters presently
operating in the United States use single absorption sulfuric acid
olants for control of sulfur dioxide emissions from sin-.er machines and,
occasionally, from blast furnaces. Single stage plants can attain S0y
levels of 2000 ppm (5.~> k/m3), and dual stage plants can attain levels
of 550 ppm (1.6 g/m3). Typical efficiencies of dual stage sulfuric acid
plants in removing sulfur oxif'es can exceed 99 percent. Other techni-
cally fc-naible S02 control methods are elemental sulfur recovery plants
and dimethylaniline (DMA) and ammo:" ia absorption processes. These
methods and their representative control efficiencies a^e listed in
Table 7.6-3.
References for Section 7.6
1. Charles Darvin and Fredrick Porter, Background Informationfrr New
Source Peformance Standards: Primary Copper,Zinc, and Lead
Sme_lt_e_r_s, Volume I, EPA-450/2-74- 002a, U.S. Environmental
Protection Agency, Research Triangle Park, NC, October 1974.
2. A. E. Vandergrift, et al.. Handbook of Emissions, Effluents, and
Control Practices for Stationary Particulate Pollution Sources,
Three volumes, HEW Contract No. CPA 22-49-104, Midwest Research
Institute. Kansas City, KG, November 1970 - May 1971.
J. A. Worcester and D. K. Beilstein, "The StatL of the Art: Lead
Recovery", Presented at che lOtn Annual Meeting of the Metallurgical
Society, AIME, New York, March 1971.
4. T. J. Jacobs, "Visit to St. Joe Iiinerals Corporation Lead Smelter,
Herculaneum, MO", Memorandum to Kmissiua Standards and Engineering
Division, Office of Air Quality Planning and Standards, U.S.
Environmental Protecticn Agency, Research Triangle Park, NC.
October 21, 1971.
5. T. J. Jacobs, "Vis^t Lo Anax Lead Company, Ross, MO", Memorandum to
Emissijn Standards and Engineering Division, Office of Air Quality
Planning and Standards, U.S. Environmental Protection Agency,
Research Triangl.2 Park, NC, October 28, 1971.
6. Written Communication from "'.. B. Paul, American ^meluing and
Refining Co., Glover, MO, to Regional Administrator. U.S.
Invironraental Protection Agency, Kansas City, MO, April 3, 1973.
7.(»-» KMISSION KACTOKS
-------
7. Emission Test No. 72-MM-14, Office of Air Quality Planning and Standards,
U. S. Environmental Protection Agency, Research Triangle Park, NC, May
1972.
8. Silver Valley/ Bunker Hill Smelter Environmental In vest j gallon (Interim
.Report) , EPA Contracc No. 68-6f-l343, PEDCo Environmental, Specialists ,
Inc., Cincinnati, OH, February 1975.
9. R. E. Iversen, "Meeting with U. S. Envl ror; nental Protection Agency and
AISI on Steel Facility Etnissloa Factors", Memorandum, Office of Air
Quality Planning and Standards, U. S. Environmental Protection Agency,
Reseprch Triangles F'ark, NC , June 7, 1976.
10. G. K. Sprelpht, "Best Practical Means in the Iron and .Steel Industry",
The Chemical Engineer, London, 2J±. 132-139 , March 1973.
11 ' Oontj-ul Techniques for Lead Air Emissions, EPA-^.50/2-77-012 , U. S. En-
vironmental Protection Agency, Research Triangle Park, NC , January 1978.
1 2 . Systems Study for Control o.' Emissions: Primary Nonferroue Smelting In-
dustry, U. ?. Department of Health, Education and Welfare, Washington,
DC, June 196'J.
13. Environmental Assessment of the Domestic Primary Copper, Lead, and_ Zinc
Industry , EPA Contract No. 68-02-1321, FEDCo-Envlronmental Specialists,
Inc., Cincinnati, OH, September 1976.
14. H. R. Jo.ies, Pollution Control in the Norferroiis Metals Industry, Noyes
Data Corporation, Park Ridge, NJ. 1972.
i
15. L. J. Duncan and K. L. fCeitz, "Hazardous Partlrulate Pollution from Typi-
cal Operations in the Primary Nonferrous Smelting Industry", presented
at the 67t'h Annual Meeting of the Air Pollution Control Assc station ,
Denver, CO, June 1974.
lh. E. P. Shea, Source Sap'pling Report: Em is signs from Te^j| Smelters, EPA
Contract No. 68-02-0228, Midwest "Research" Institute , Kansas City, MO,
1973.
17. R. C. Hussy, Source Testing: Emissions fron a Primary Lead SnieiUer^, EPA
Contract No. 68-02-0228, Midwest Research Institute, Kansas City, MO,
1973.
18, Emission Test No. 73-PLD-l, Office of Air Ou.'-Mty Planning and Standards,
U. S. Envlronnennal PcotR'-.tion Agency, Research Triangle Park, NC, Octo-
ber 1973.
19. Interim Report on Control Techniques for Leat] Air Emissions, Development
"of Le^d~Einlssiofr Vac tors [, and~~l~975 HaticTndr^Laad Emi'sslon Irventory, RPA
ContracT. NoT~68^f)"2 -1 375, PEDCo-Environt,iental 55pc>ci allsts , Inc., Cincin-
nati, OM, JUOP 1976.
12/81 Metallurgical Industry 7.6-9
-------
20. S. '"yatt, et al._, Preferred Standards Path Analysis j^n Lead Emissions
from Stationary Sources, Office of Air Quality Planning and Standards,
Research Triangle Park., NC, September
21. A. E. Vanderg.lft, et al. , Partlcula'^e Pollutant System Study - Mass
Missions, PR-203-128, PB-203-522 and PB-203-521, U. S. Environmental
Protection Agency, kesearch Triangle P^.rk, NC, May 1971.
22. V. S. Katarij et aK , Trace Pollutant EmiBslons from the ProcesB_ing of
Hetallic Ores, EPA-650/2-74-1 15, U. S. Environmental Protection Agency,
Research Triangle Park, NC, October 1974.
7.6-10 EMISSION FACTORS 12/81
-------
7.7 ZINC SMCLTINC
7.7.1 Process Description^»2
A-* stated previously, most domestic zinc comes, from zinc and lead ores.
Another important source of raw material for zinc metal ha;; been zinc oxide
from fuming furnaces. For efficient recovery rf zinc, sulfur roast be removed
from concent rates to a level o? leas than 2 percent. This Is done by fluid-
ized beds or rr, iltiple-hearth roasting occasionally followed by sintering.
Metallic zinc can b<; produced from the roasted ore by the horizontal or
vertical retort process or by the electrolytic process if a high-purity zinc
is needed.
7.7.2 Emissions and Controls »^
Dust, fumes, and sulfur dioxide are emitted from zinc concentrate roast-
Ing or sintering operations. Partlculates may be removed by electrostatic
baghouses. Sulfur dioxide may be converted dlreccly into
vented. Emission factors for zinc spelt'ng are presented
pr-^cipitators or
sulfurlc acid or
in Table 7.7-1.
TABLE 7.7-1. EMISSION ^ACTORS FOR PRIMARY ZINC
SMELTING WITHC'JT CONTROLS*
EMISSION FACTOR RATING:
Type of operation
Partlculates Sulfur oxides
Ib/ton kg/Mg Ib/ton
kg/Mg
Ib/ton
Ore unloading, storage
and transfer
Roasting (nvJltlple-
hearth)C
I51nteringd
Horizontal retorts^
Vertical retorts^
Electrolytic process
1.95 3.85
(1-7.9) (2.0-5.7)
60
45
4
50
is 1.5
120
90
8
100
3
550
e
-
-
--
1100
e
-
-
—
19.25
(13.5-25)
1.2
2.25
(2-2.5)
—
38.5
(27-50)
7.4
4.5
(4-5)
—
''Approximately 2 unit weights of concentrated ore are required to produce
1 unit weight of zinc metal. Emission factors expressed as units per unit
weight of coricen: ratL-.i ore produced. Dash indicates no available data.
''References 1-3.
c?.ef eren.:es 4-5.
"References 5-6.
e Included in SO
losses from roasting.
Re fere ace
12/81
Metallurgical Industry
7.7-i
-------
References for Section 7.7
J' Control 'Techniques for Lead Air Emissions, EPA-450/2-77-012 , IJ. S. fi.ivi-
rcnnentol Protection Agency, Research Triangle Hark, NC, December 1977.
2. H. R. Jones, Pillution Control in the Nonferroua Metals Industry, No yes
Data Corporation, Park Ridge, NJ, 1972.
3. G, B. Came, Coiicrol Techniques for Lead Emissions. Draft Report, U. S.
Environmental Protection Agenry, Research Triangle Park, NC, February
1971.
4. R. L. Duprey, Compilation of Air Pollutant Emission Factors, U, S. DHEW,
PUS, National Center for "Air Pollution Control, Durham, NC, PH5 Pub-
lication Number 999-AP-42, 1968, p. 26-28.
5. A. Stern (ed), "Sources of Air Pollution and Their Control, Air^ Pollution ,
Vol III, 2nd Ed.. New York, NY, Academic Press, 1968, p. 182-186.
6i G. Sallee, Private communication on Partlculate Pollutant Study, Midwest
Research Institute, Kansas City, MO, prepared for National Air Pollution.
Control Administration, Durham, NC, under Contract Number 22-69-104,
June 1970.
7. Systems Study for Control of Emissions in the Primary Nonferrous Smelting
Industry, 3 Volumes, San Francisco, Arthur G. McKae and Company, June
J969,
7.7-2 EMISSION FACTORS 12/81
-------
7.8 SECONDARY ALUMINUM OPERATIONS
7.8.1 Genera]
Secondary aluminum operations Involve the cleaning, melting,
refining and pouring of aluminum recovered from scrap. The processes
use*' to convert scrap aluminum to secondary aluminum products such
as lightweight metal alloys for Industrial castings and Ingots are
presented In Figure 7.8-1. Production Involves two general classes
of operation, scrap treatment and smelting/refining.
Scrap treatment Involves receiving, sorting and processing
scrap to remove contaminants and to prepare the material for smelting.
Processes based on mechanical, pyroraetallurgical and hydrnmetal-
?.urglc,i.i techniques are used, and those employed are selected to
"ilt the type of scrap processed.
The smelting/refining operation generally involves the following
steps'.
• charging • mixing
• melting • demagging
• fluxing • degassing
• alloying • skironing
• pouring
All of these steps may be involved in each operation, with process
distinctions being in the furnace type used and in emission charac-
teristics. However, as with scrap treatment, not all of these
steps are necessarily incorporated into the operations at a
particular plant. Some steps may be combined or reordered, depending
on furnace design, scrap quality, process inputs and product
specifications.
Scrap treatment - Purchased aluminum scrap undergoes Inspection
upon delivery. Clean scrap requiring no treatment is transported
to storage or Is charged directly into the smelting furnace. Tha
bulk of the scrap, however, must be manually SOLted as it passes
along a steel belt corveyor. Free Iron, stainless steel, zinc,
brass and oversized materials are removed. The sorted scrap then
god3 to appropriate scrap treating processes or is charged directly
to the smelting furnace.
Sorted scrap is conveyed to a ring crusher or hammer mill
where the material is shredded and crushed, with the Iron torn away
fron the aluminum. Tne crushed material is passed over vibrating
screens to remove dire and fines, and tramp Iron Is removed by
magnetic drums and/or belt separators. Baling equipment compacts
bulky aluminum scrap into 1x2 meter (3x6 foot) bales.
4/81 Metallurgical Industry 7.8-1
-------
FUETREATMENT
-vj
00
BULL ,
SC"AP
I/I
CO
s
z
Tl
n
H
CD
00
-^
FLU
-M>
FLU
-»•
ELEI
I
SMELTING/REFINING
1 fr«EL
HEVERMRATORY
(CHLORINE)
SMELTING/REFINING
FLUOBHIE „
REVERIERATORV
(FLUORINE)
SMEI. TING/REFINING
-V
EL
-•»
X-i i-FUEL
CRUCIBLE
-••
/ AL10Y \
r»-l (K80TS I
vV
/^~N
••H BILLETS \
^1 NOTCHED \
-W SHOT j
^H METAl J
1TRICITY Ftux "^ZCT
INDUCTION
SMELTING/REFINING
(_ ^_^
Figure 7.&1. Process flowdiagran for the secondary aluminum processing industry
-------
Pure aluminum cable wlt.li steel reinforcement or insulation is
cut by alligator type shears and granulated or further reduced in
hammer mills, to separate the Iron core and the flastic coating
from the aluminum. Magnetic processing accomplishes iron removal,
and cir classification separatee *.he Insulation.
Borings and turnings, in moet cases, are treated to remove
cutting oils, greases, moisture and free iron. The processing
steps involved are (&) -rushing in hammer mills or ring crushers,
(b) volatilizing the noist.'re and organics in a gas or oil fired
rotary dryer, (c) screening th..- ilried chips to remove aluminum
fines, (d) reracving iron magnetically and (e) storing the clean
dried borings in tote V^ves.
Aluminum can be recovered from the hot drofs discharged from a
refining furnace by batch fluxing with a salt/cryolite mi/ture in a
mechanically rotated, refractory lined barrel furnace. The met.il
is tapped periodically through a hola in its base. Secondary
aluminum recovery from cold dross and other residues from primary
aluminum plants is carried out by means of this batch fluxing in a
rotary furnace. IP 'he dry milling process, cold aluminum laden
dross and other residues are processed by milling, screening and
concentrating to obtain a product containing at least 60-70 percent
aluminum. Ball, rod or hammer mills can be used to reduce oxides
and nonmetHllics to fine powders. Separation of ^Irt and other
unrecoverable^ from the metal is achieved by screening, air
classification and/or raafni'.tic separation.
Leaching involves (a) wet milling, (b) screening, (c) drying
and (d) magnetic separation to remove fluxing salts and other cion-
recoverables from drosses, skimmings and slags. First, the raw
material is fed into a long rotating drum or an attrition or ball
mill where soluble contaminants are leached. The washed material
is then screened to remove fines and dissolved salts and is dried
and paaaed through a magnetic separator to re-move ferrous materials.
The nonmagnetics then are stored or charged directly to the smelting
i rnace.
In the roasting process, carbonaceous materials associated
with aluminum foil ar^ charred and then separated from tha metal
product.
Sweating is a pyrometallurgiaal process used to recover
aluminum from high iron contenL scrap. Open flame reverberatory
furnaces T.a> b-> used. Separation is accomplished as aluiniaum and
other low milling constituents melt and trickle down the hearth,
through a grate and into >:ir cooled molds or collecting pots. This
product is termed "sweated pig1 . The higher melting materials,
including iron, brass and oxidation products formed during the
.sweating process, ara periodically r^movud from the furnace.
4/31 Metallurgical Industry 7.8-3
-------
Smelting/refining - In reverberatory (chlorine) operations,
revefboratory furnaces are conmonly used to convert clean sorted
scrap, sweated pigs or some untreated scrap to specif .'cation ingots,
shot or hot metal. The scrap Is first charged tu the furnace by
some mechanical me,,ns, often through charging wells designed to
r . rujlt introduction of chips and Itg'iit scrap be!uw the surface of a
previously melted cnarge ("heel"). Batch processing is generally
practiced for alloy ingot production, and continuous feeding and
pouring are generally used for products having lessi strict
specifications.
Cover fluxes are used to prevent air contact with and consequent
oxidation of the mult. Solvent fluxes react with rummetall Lcs .such
as burned coating residues and dirt to form insoluhus which float
to the surface as pun of the slag.
Alloying agents are charged through tlie forewe.11 in amounts
determined by product specifications. Injection of nitrogen or
other inert gases into the nolt-^r; n>etal can be used to aic1 in
raising dissolved ^ases (typically hyJroa-en) ind intenn_xed snlids
to the surface.
Demagging reduces the magnesium content of the. nolten charge
fnm approximately 0.3 to 0.5 percent (typical scrap value) to
about 0.1 percent (typical j.roduct line alloy specification). When
demagging with chlorinj gas, chlorine is injected unHer pressure
throug.i c irbon lances to react with tmgnesiun and aluminum as it
bubbles to the. surface. Other chlorinating agents, or fluxes, are
sometimes used, such as anhydrous aluminum chloride or chlorinated
organics.
In the skimming step, contaminated fiemlsolid fluKus (dross,
slag or skimmings) are ladled from the surface of the melt and
removed through the fj-jewel I. The melt Id then cooled before
pouring.
The. reverberatory (fluorine) process is similar to the
reverberatory (chlorine) smelting/refining process, except that
aluminum fluoride (A1F-,) is employed In the damaging step Instead
of chlorine. The AlF-j "eacts with magnesium to produce molten
metal alunlnum and solid magnesium fluoride s;ilt 'Jh Lch floats to
the surface of the molten aluminum and is sk.tinned off.
TliH crucible smelting/refining proce-j.s is used to me't snail
batches of aluminum scrap, generally limited to bOO kg '101)0 Ih) or
less. Tie 7iPt.il treating process steps are essentially the same ns
Less. lie 7iet,n creating proce
those of reverbefatory furnaces
Ti"j induction smel t Ing/ref Lns ig pro-.-ess is designed to produce
hardliners hy blending pun> alui.ilnn.a and hardening agents In an
el«ctiTlc irductLon furnace. The process seeps include charging
scrap to tre Furnace, malting, adiiing an.-l hle.ndinj; the hardening
ag^-nt, skimaiiiig, pouring and casting into notched bars.
7.8-A KMiSSLON FACTORS ^/
-------
7.3.2 Emissions and Controls
Table 7.3-1 presents emission factors for the principal
emission sources in secondary aluainun operations. Although eich
step in scrap treatment and snel ting/ refining is a. potential source
of emissions, emissions from most of the processing operationr are
either not characterized here or cult only small amounts of
pollutants.
Crushing/screening produces small amounts of metallic and
nonmetallic dust. Baling operations produce participate emissions,
primarily dirt and alumina dust resulting from aluminum oxidation.
Shredding/clessifylng also emits small amounts of dust. Emissions
from these processing steps are normally uncontrolled.
Burning/drying operations emit a wide range of pollutants.
Afterburners are used generally tj convert unburnt-JI hydrocsrbons to
CO 2 and H20. Other gases potentially present, depending on the
composition of the organic contaminants, 'nclude chlorides, fluo-
rides and sulfur oxides. Oxidized aluminum fines blown out o2 the
dryer by the combustion gases comprise particulate emissions. Wet
scrubbers are sometimes used in place of afterburners.
Mechanically generated dust from the rotating barrel dross
furnace constitutes the main air emission of hot dross processing.
Some fume a are produced from the fluxing reactions. Fugitive emis-
sions are controlled by enclosing the barrel in a hood system and
by ducting the stream .0 a baghouse. Furnace off gas emissions,
mainly rlisxing salt fumti, are controlled by a. venturi scrubber.
In dry milling, large amounts of dust are generated from the
crushing, milling, t-creening, air classification and materials
transfer steps. Leaching operations may produce particulate emis-
sions during drying. Emissions fro-n roasting are partlculates from
th'i charring of carbonaceous materials.
Emission*, from sweating furnaces vary with the f«^d scrap
Compos it Ion. Smoke may result from incomplete combustion of organic
contaminant* (~.g., rubber, oil arid grease, plastics, paint, card-
board, paper) which may be present. Fumes can result from oxidation
cf r.agnesium and zinc contaminants aad from fluxes IP. recovered
drosses and skims.
Atmospheric emissions from reverberatory (chlorine) smelting/
refining represent a significant fraction of the total particulate
and gaseous effluents generated in the secondary aluminum industry.
Typical farnace effluent gases contain combustion products, chlorine,
hydrogen chloride and metal chlorides of zinc, magnesium and aluminum,
aluminum oxide and various metals and metal compounds, depending on
the quality of scrap charged. Particulate emissions from one
secondary aluminum smelter have a aiz^. distribution of D^g - 0.4M.
Mev.alli rp-icil Industry
-------
TAP1E 7.8-1. PART1CULATE J-MISSFON FACTORS FOR SECONDARY
ALUMINUM OPERATIONS3
Operation
Electrostal-? Eulsslon
L'nsortioll«d Bjghojsa creclpltaior F*<:Tor
kg/Mg Ib/'luu ''•£.' '*.t Ib/ton ''g/Hg Ib/ton RAt'r.',;
Sweating furn..cj
Sieltlng
7.25
0.95
Reverb«rstory furnacGC 2.15
d
1.65
3.3
1.9
0.65e 1.3e
0.6S
1.3
Cilorlnatton st.itlon
500
MOO
25
50
Rrfercnce 2. t'.miFsion *ac:ora «xpr«Bsed as jn4 . i per urlt weight of metsl
processed. Factors app^.v rnly to Al metal recovery operations.
Based in averages of two source teats.
Baand in averages of ten jourcu tasts. Standard mvlatlon of uncontrolled
emission factor Is 17.5 k^/Mg (3.5 Ib/ton), Chat of con.rolltn tACtor 14 Q.H kg/Mg
^(0.3 ':b/ten).
L£xpre9i«d as kg/M^ (la/ton) of chlorlnn us.-d. Based on *verag*D or r«ti idir^e teata.
StanJard deviation of jnconi.rolla-1 enlsslon factor Is 215 *g/Mg (430 Ib/ton), of
controlled factor, 18 kg/Mg (36 Ib/ton).
Thla factor nay bi* lover if a coaccd bi^hc ;a« IF used.
Emissions from rev/erberatory (fluorine) sraelting/ref ining ate
similar to thos* from reverberatory (chlorine) smeltlng/ref Inlns.
Thi use of Alf-j rather than chlorine In the demagglng step reduces
demagging emissions. Fluorides are emitted as gaseous fluorides
(hydrogen fluoride, aluminum and magnesium fluoride vapors, and
silicon tetraf luorlde) or as 'justs. Vent'iri scrubbers are usually
used for fluoride emission control.
References for Section 7.8
W.M. Coltharp, e_t aj . , Multimedia Envifonmental Assessment of
the Secotidary Nonf errous Metal Industry, Draft Final Report,
2 vols., EPA Contract No. 68-02-1319. Radian Corporation,
Austin, TX, June 1976.
W.F. Hammond and f>.M. Weiss, Unpublished report on air
contaminant enisslons from metallurgical operations In Loa
Angeles County, Los Angelas County Air Pollution Control
District, July 1964.
R.A. Baiter, fet ^al . , Evaluation of a Coattid Baghpuse 3t a
Secondary AlumV.uiu ame'lter, EPA Contract Ko. 68-02- U02,
Environuitntal Science and Engineering, Inc., Gainesville, FL,
October 1976.
Air Pol lut ion Engineering
2d Ed'.tion, AP-40, U.S.
Environmental Protection Apisncy, Research Triangle Park, NC,
May ly?3. Out of Print.
7.8-6
EMISSION FACTORS
-------
5. E.J. Petkus, "Precoated Baghous^. Control for Secondary Aluminum
Smelting", Presented at the 71st Annual Meeting of the Air
Pollution Control Association, licuetjn- TX, .Tuna 1973.
Metallurgical. Ludaatry 7.8-7
-------
7.9 SECONDARY COPPER SMELTING A'»D ALLOYING
7.9.1 Process Description1*3
The secondary coppei industry processes scrap metals ror the recovery of copper. Products include
refined capper <>i copper alloys in forms such as ingots, vvirebar, anodes, und shot. Copper alloys are combinations
ol copper with other materials, noiably, tin, zinc, arJ lead. Also, for special applications, combinations include
such metals as cobalt, mangane e, iron, nickel, cadmium, and beryllium and nonmetals «!>.-.h as arsenic auJ
silicon.
The principal processess involved in copper recovery are scrap metal pretreatmenl and smelting.
Pretreatmenl includes cleaning and concentration to prepare the material for the smelting furnace. Smelting
involves heating and treating the scrap to achieve separation and purification of specific metals.
The feed material used in the recovery process can l>« a.-iy metallic scrap containing a useful amount of
copper, bronze (ropper and tin), or brass (copper rrH line). Traditional forms are punching:, turnings and
borings, defective or surplus goods, metallurgical residues such as slags, skimmings, and drosses, and obsolete,
worn out, or damaged articles including automobile radiators, pipe, wire, bushings, and be»ring:>.
The type and quality of the feed material determines the p.ocejses the smeiicv will use. Due 10 it.e large
variety of possible fred materials avail?*>!e, tho method of operation varies greatly between plan's. General!'-. *
secondary cupper facility deals with less pure raw materials and produces a more refined product, whereas bruss
and bronze alloy processors take cleaner scrap and do less purification and refining. Figure 7.9-] is a flowsheet
depicting the major processes that can be expected in a secondary copper smelting operation. A brass and bronze
alloying operation is shown in Figure 7.9-2.
Pretreatment of the feed malp.rial cm r-e accomplished using seveial different procedures, either
9','paralr)-- or in combination. F'ced scrap is concentrated by manual and mechanical methods such as sorting.
stripping, shredding, and magnetic separation. Feed scrap is sometimes briquetted in a hydraulic press.
Pyrometalmrgical pretreatment may include sweating, Hirniiv, of insulation (especially from wire scrap), and
drytr.g (burning off oil and volatiles) in rotary kilns. H v^lrorr etal'urgical methods include flotation and leaching,
with chemical recovery.
In smelting, low-grade scr. pis melted in a cupola furnace, producing "black copper" (70 toB'J percent Cu)
anrl slag; these .ire often iepura,ed in a reverberatory turnace. from which the melt is transferred to a converter or
dectric furnace to produce "blister"' copper, which is ^ to 99 percent Cu.
Blute opper ma> bepourec' toproduce shot or castings, but is often further refined electrolytic-ally or ..y
fire rrfming. The fiie-refining process is esset'Hally the same as that described for the primary copper smelting
industry (S^ct-on 7.3.1). The seque.irp of events in fire-refinii g is (1) charging, (2) meltine in an oxidizing
atmosphfin , (3) .skimming the. slag, (4) blowing with air or oxygen, (5) adding flux* •,, (6) "poling" or olh rwise
providing a reducing atrno.sphere, (7) reikimming, and (8) pouring.
To produce bronze or brass rather than copper, an alloying operation is required. Clean, selected bronze
.ind brass scrap is charged io a melting furnace with alloys to bring the resulting mi: ;ur.' to the desired final
ccmposition. Fluxes art added to remove impurities and to protect thc.-nelt against oxid; ;cn by air. Aii or oxygen
may b-- blown through the melt lo adjust the compoai.i.'n by oxidizing exres? zinc.
With 7inc-rich feed such 3-, hrass, the zinc oxide concentra'inn in the exhaust gas is sometimes high
enough to make recover;, for its metal value desirable. This process is accomplished by vaporizing the zinc from
the melt a' hiph te iperature and capturing tai- oxide downstream :n a process baghouse.
32/77 Metallurgical Indualry 7.9-1
-------
ENTERING THE SYSTEM
LEAVING THE SYSTEM
LOW GRADE SCRAP
(SLAGS, SKIMMINGS,
DROSSES, CHIPS,
BORINGS)
FUEL
AIR
PYROMETALLURGICAL
PRETRFATMENT
DRYING!
THtATED
SCRAP
GASES, DUST, METAL OXIDES
' TOrONTROI EQUIPMENT
FLUX.
FUEL-
CUPOLA
CARBON MONOXIDE, PARTICIPATE
. METAL OXIDES, TO AFTERBURNER AND
P<\RTICULATE CONTROL
»-SLAG TO DISPC JAL
BLACK
COPPER
FLUX-
FUEL-
AIR-
t
SLAG
SMELTING FURNACE
(tEVERBERATORY)
OASEC AND METAL OXIUES
• TO CONTROL EQUIPMENT
SEPARATED
COPPER
FLUX-
FUEL-
AIR—
1
SLAG
CONVERTER
BLISTER
COPPER
AIR
-*.
-to
REDUCING MEDIUM,
(POLING)
GASES AND METU OXIDES
' TO CONTROL EQUIPMENT
BLISTER
COPPER
i
CASTINGS AND SHOT
PRODUCTION
SLAG
FIRE REFINING
FUGITIVE -?!ETAL OXIDES FROM
. POURING TO EITHER HOODING
OR PLANT ENVIRONMENT
GASES, METAL DUST,
'TO CONTROL DEVICE
RfcFINED
COPPER
7.9-2
7.9-T. Low-grade copper recovery.
EMISSION FACTORS
12/77
-------
ENTERING THE SYSTEM
LEAVING THE SYSTEM
HIGH GRADE SCRAP
IWIHE, PIPE, BEARINGS.
PUNCHIXGS, RADIATORS)
FUEL
AIR
MANUAL AND MECHANICAL
PRETREATMENT
ISOlTING)
DESIRED
COPPER SCRAP
FLUX
FUEL
ALLOY MATERIAL-
IZING, TIN, ETC)
COPPER
• FUGITIVE nUST TO ATMOSPHERE
I L
-»-UNDESIRED SCRAP TO SALE
DESIRED BRASS
AND BRUNZE SCRAP
/.'IRE B
FUEl * a
AIR *
B
1
SEATING
»-LEAD.
GASES, METAL OXIDES TO
CONTROL EQUIPMENT
»-LEAO. SOLDER. PAP«ITT METAL
BRASS AND
BRONZE
MELTING AND
ALLOYING FURNACE
ALLOY
MATEHIAL
•PARTICULATES, HYDROCARBONS,
ALDEHYUES. FLUORIDES, AND
CHLORIDES TO AFTERBURNER
AND PARTICIPATE CONTROL
—w-METAL OXIDES TO
CO.JTHQL EQUIPMENT
—»-SLAG TO DISPOSAL
CASTING
FUGITIVE METAL OXIUES GENERATED
DURING PL URING TO EITHER PLAN1
ENVIRONMENT OR HOODING
12/77
7.9-2. High-grade brass and bronze alloying.
Metallurgical industry
7.9-3
-------
The final step iu hlways casting of the suitably alloyed or refined metal iiHoadesirf.d form. i.e. shot, wirebar,
anodes, cathodes, invots, or other cat: Jiapes. The melal from the melt is usually poured inio a ladle or a small
pot, which serves the functions of a surge hopper and a flow regulator, then ir'.(- a mold.
7.9.2 Emissions an 1 Controls
The principal pollutants emitted from secondary copper sm«-hiii|' activities are parti ulate matter in
various forms. Removal of insulaiion from wire by burning causes particul-.te emissions of metal oxides and
unburned insulation. Drying of chips and borings to remove excess oilsard rutting fluid? can cause discharges of
large amounts of dense smoke r oi i si sting of soot ind unburned hydrocarbons. Prtrtictilale emissions from the top
of a cupola furnace consist of melal oxide fumes, dirt, and dus! from limestone and coke.
The STielung pro sss utilizes large volunes of ai' to oxidize sulfides, zinc, anJ other undesirable consti-
tuents of the feed. This procedure generates much participate matter in (he exit gas strcan. The wide variation
among furnace types, charge types, quality, extent of pretreaiment, and size of charge is reflected in a broad spec-
trum of particle sizes and variable gram loadings in the escaping gases. One major factor contributing to diffei-
cnces in emission rates is the amount of zinc present in scrap feed materials; the low-boiling zinc evaporates and
combines with air oxygen to give copious fumes of zinc oxide.
Metal oxide fumes from furnaces used in secondary smelters have been controlled by baghouses,
electrostatic precipitators, or wet scrubbers. Efficiency rf cont.ol by baghouses may be better than 99 percent,
but cooling systems are needed to prevent the hot exhaust gases from damaging or destroying the bag filters. A
two-stage system employing both wcter jacketing and radiant cooling is common. Electrostatic precipitators are
not a- well suited to this application, having a low collection efficiency for dcr.se participates such as oxides of
lead and zinc. Wet scrubber installations are albo relatively ineffective in the secondary copper ir lustry.
Scrubbers are useful mainly for pai tides larger than 1 micron, (/jm) but the metul oxide fumes generated are
generally submicron in size.
Porticulale emissions associated with drying kilns can be similaily controlled Drying temperatures up to
15(/"C (300° F) produce relatively cool exhaust gates, requiring no precooling for control hy baghouses.
Wire burning generates murh particular matter, largely unturned crrnbustib'es. These emissions can he
effectively controlled by dirTt-flame afterburners, with an efficiency of 90 percent or better if the afterburner
rombusiion temperature is mainlined above 1000° C (1800° F). If ihe insulation contains chlorinated organics
such as poly vinyl r.hlorid . hydiOgen chloride gas will be generated ami will riot be controlled by the afterburner.
One source af fugitive emissions in secondary smelter operations is charging of scrap into furnaces
"ontaining molten metals. This often occurs when tht scrap being processed isiiol sufficiently compact to allow a
foil charge lo fit into the fyrnace prior to heating. The introduction of additional material onto the liquid r.iftal
surface produces significant amounts of volatile and combustible materials and smoke, ^'hicl. can escape through
the charging uoor. Pdquettmg the rharge offer? a possible means uf avoiding the necessity of such fractional
charges. Wi;en fractional charging cannot be eliminated, fugitive emissions are reduced by turning off the
furnace burnr rs during charging. This reduce5 the flow of exhaust gases and rnhanres the ability of 'he exhaust
control system to handle th'J eini»bioiis.
Metal oxide fumes are generated not only during melting, but also during pouringof the molten metal into
the molds. Other dusts may he generated by the charcoal, or other lining, used *,] asrociat:on with the moid.
Covering thr iitt-! surface with groun'1 chaicoal is a method used to make "smooth top' ingou. Thi> pruccss
creates a shower o1 sparks, i .'leading frr'ssions into the plant environment a! the vicinity of the furnace top ind
the molds being filled.
iyii fa< tur averages and rnn°es for six different lypr>s of furnaces are prcsfnleiJ in Tablw 7.9-1.
.<>-4 EMISSION FACTORS J2/77
-------
TABLE 7.9-1.
PARTICULATE EMISSION FACTORS FOR FURNACES USED IN SECONDARY
COPPER SMELTING AND ALLOYING PROCESSES8»b
EMISSION FACTOR RATING: B
Paniculate
Furnace and charge type
Cupola
S<*r«r Iron
Ineulxed copper wire
Scr*" ,~pper aud brass
Co 1 1 ro 1
c^jltinpnt
Ko.it
NOT.;
KdPc
None
KSP
It* /M*
sucrngc r^ngc
0.002
120
5
15 10-40
1.2 1-1.4
Ib/ton
average
0.003
230
10
70
2.;
L.-ad*1
K«/1a Ib/ton
raojjc
..
-
-
60-80
2-2.8
River be rat'jry
High l-'.ad alloy (5BZ
Lia4
R«d/yeUotf brut (IV.
Lead
Ofisr aMoyi (71 \r-ad)
Copper
Bran and bronze
Rotary
Bran and bror-e
Ctuclbla and pot
Bran and bronze
llsctric Arc
Copper
Bran and bronte
Electric Induction
Copper
Braas and bronze
None
None
None
Non«
Baghouac
None
Baghouie
None
ESP
None
ESP
None
Baghouse
None
Baghouae
Nona
Baghouae
None
Raghouae
2.<4
0.2
14
1.1
15IJ
7
11
0.5
2.5
0.5
5.5
3
3.5
0.25
10
0.35
0.4-15
0.1-0.3
0.3-35
0.3-2.5
50-250
3-10
1-20
3-10
1-4
O.C2-1
2-9
0.01-0.65
5.1
0.4
36
2.6
300
11
21
1
5
1
11
6
7
0.5
20
0.7
0.8-30
0.3-0.6
0.6-70
0.6-5
100-500
6-19
2-40
6-19
2-8
0.04-2
4.-IB
0.5-40
0.01-1.3
2s,
6. f,
2.5
50
13.2
5.0
•Factors fur high lead alloy (58 percent lead), red and yellow brass (15 percent: lead), and other
alloy* (7 percer.t leid) produced in the reverberator? furnace are bated on unit weight procured.
All other factors given In term of raw materials charged to unit. Dash Indicates no available
infornation.
bfhe Information for partlculate In Table 7.9-1 was based on unpublliiied data furnlahcd by the
following:
Philadelphia Air Managenane Servlcei, 'hlladelphli, PA.
N«v Jarny Dipartaent of Environmental Protection, Trenton, NJ.
Nfw Jeraay Departaint of Envlronnentil Protection, Metro Field Office, Sprlngfle'd. NJ.
New Jersey Department of Environmental Protection, Newark Field Office, Navtrk, NJ.
New York Stati Deptrtoent of Environmental Conservation, New York, NY.
Ths City of New York Dapartaunt of Air Rciourcsi, Sew York, NY.
Cook County DspartiMnt of Envlronnertal Control, Mayvood, IL.
Wayne County Department of Health, Air Pollution Control Division, Detroit, HI.
City of Cleveland Department of Public Health and Welfare, Division of Air Pollution
Control, Cleveland, OH,
State of Ohio Environmental Protect lor Agency, Columbus, OH.
City of Chicago Department of Environmental Control, Chlcigo, IL.
South Coast ALr Quality Managewnt District, Los Angeles, CA.
equals electruitatlc: preclpltator.
o 1, 5-6.
JO/80
Mocallurglcal Industry
7.9-5
-------
References for Section 7.9
1. Air Pollution Aspects of Brass and Bronze Smelting and Refining Industry,
U.S. Department of Health, Education" and Welfare, National Air Pollution
Control Administration, Raleigh, NC, Publication No. AP-58, November 1969.
2, J. A. Danielson (ed.), Air Poll at-ion Engineering Manual (2nd Ed.), AP-40,
U.S. Environmental Protection Agency, Research Triangle Park, NC, 1973.
Out o? Print.
3. Emission Factors and Emission Soarce Information for Primary and Secondary
Copper Smelters, U.S. Environmental Protection Ag2ncy, Research Triangle
Park, NC, Publication No. EPA-450/3-77-C51, December 1977.
^. Control Techniquesfor LeadAir Emissions, FPA-A50-Z/77--012, U.S. Environ-
mental Protection Agency, Research Triangle Park, \'C, December 1977.
5. H. H. FukubayasM, et al., Recovery of Zinc ar.d Lead from Brass Smelter
Dust, Report of Investigation No. 7880, Bureau cf Mines. U.S. Department
of the Interior, Washington, DC, 1974.
6. "Air Pollution Control in the Secondary Metal Industry", Presented at the
First Amu a?. National X^s^-'lstion of Secondary Materials Industries Air
Pollution Control Workshop, Vittsburgh, PA, June 1967.
7.9-6 EMISSION FACTORS 12/81
-------
7.10 CRAY IRON FOUNDRIES
7.10.1 General1
Gray Iron foundries produce gray iron castings by melting,
alloying and molding pig iron ind scrap iron. The process flow
diagram of a typical gray iron foandry is presented in Figure 7.10-1.
The four major processing operations of the typical gray iron
foundry are rav materials handling, rattal melting, told and core
production, and casting and finishing.
Raw Materials Handling - The raw material handling operations
include the receiving, unloading, storage and conveying of all raw
materials for tha foundry. The raw materials ustd by gray iron
foundries are pig iron, Iron and steel scrap, foundry returns,
metal turnings, alloys, carbon additives, coke, fluxed (limestone,
soda ash, fluorspar, calcium carbide), sand, sand additives, and
binders. These raw materials are received in ships, railcars,
trucks and containers, transferred by truck, loaders and conveyers
to both open piles and enclosed storage areas, and then transferred
by similar means from storage to the processes.
Metal Melting - Generally the first step in the metil melting
operations ia scrap preparation. Since scrap is normally purchased
in the proper size for furnace feed, scrap preparation prijiarily
consists of jcrap decreasing. This is very important for electric
induction furnaces, as organics on scrap can cause an explosion.
Scrap may be degreased with solver.ts, by centrifugation or by
combustion in an incinerator or htrater, or it may bt? charged with-
out treatment, as is often the case with cupola furraces. After
preparation, the scrap, iron, alloy and flux are weighed and charged
to the furnace.
The cupola furnace is the raa;,or type of furnac; use<' in tht
gray iron industry today. It is 'Cypically a vertical refractory
lined cylindrical steel shell, chargeu at the top with alternate
layers of uietal, coke and flux. larger cupolas are water cooled
instead of refractory lined. Air introduced at the bottom of the
cupola burns the coke to r.ielt th
-------
FUMES AND-* ;
RAM MATERIALS
UNLOADING. STORAGE.
TRANSFER
• FLUX
• METALLICS
• CARBON SOURCES
• SAND
• BINDER
----^HYDROCARBONS
AND SMOKE
SCRAP
PREPARATION
i *
FURNANTE
•CUPOLA
• ELECTRIC AHC
• INDUCTION
•OTHER
•FURNANCE
VENT
• FUGITIVE FUMtS
AND DUST
TAPPING
TREATING
-^-FUGITIVE FUMES
AND DUST
MOLD POURING,
COOLING
SAND
OVEN VENT
CASTING
St.'AKEOUT
-FUGITIV5
DUST
CDOUNG
L
CLEANING.
FINISHING
FUME.SAND
FUGITIVE
DUST
.FUGITIVE
OUST
SHIPPING
Figure 7.10-1. Typical flow diagram of a grey iron f'ji ndry.
7.10-2
EMISSION FACTOR;'.
4/81
-------
the side. The molten metal Is tapped by tllc.ng and pouring through
a hole in the side. Melting capacities range up to LO Mg (20 tons)
per hour,
A third furnace type used li the gray iron industry is the
electric induction furnace. Induction furnaces are vertical refrac-
tory lined cylinders surrounded by electrical colls energized with
alternating current. The resulting fluctuating magnetic field
heats the ra3ta]. Induction furnaces are kept closed except when
charging, skimming and appir.g. The molten metal is tapped by
tilting and pouring through a hole in the aide. Induction furnaces
ate also used with othev furnaces to hold and superheat the cnarge
after melting and refining in another furnace.
A small pt'rcenta^e o* melting in rhe gray it on industry is
also done in air furnaces, reverberatory furnaces, pot furnaces and
Indirect arc furnacas.
The basic melting process operations are 1) furnace charging,
in which the met&l, scrap, alloys, carbon and flux are added to the
furnace, 2) raeltirg, during which ths furnace remains closed,
3) backcharging, which involves the addition of more metal and,
possibly, alloys, 4) refining and treating, during which the ".herals-
try is adjusted, 5) slag removing, and 6) tapping molten tetal into
a ladle or directly into molds.
Mold Hud Core Production - Cores are molded sand shapes used to
make the internal voids in castings, and molds are forms used to
ghepe the exterior of castings. Cores are made by mixing sand with
organic binders, molding the sand into a core, and baking the core
in an oven. Molds v,:e prepared by using a mixture of wet sand,
clay and organic additives to make the mold shapes, and then bv
drying with hot air. Increasingly, cold setting binders are beirz;
used in both core and raoM production. Used sand from shakeout
operations is recycled to the sand preparation area to be cleaned,
screened and reused to make molds.
Casting and Finishing - When the melting proctss is complete, the
molten metal is tapped and poured into a ladle. At this point, the
molten metal uiay be treated by ;"!ditlon of magnesium to produce
ductile iron by the addition of soda ash or lime to remove sulfur.
At times, graphite may be innoculated to adjust carbon levels. The
treated raoltsn metal is then poured into molds and alb wed partially
to cool. The partially cooled castings are placed on a vibrating
grid where the mold and ooru sand is shaken away £rora the casting.
The sand is returned to the mold manufacturing process, and the
castings are allowed tc coo] further in a cooling tunnel.
In the cleaning ard finishing process, burrs, risers aid gates
art broken off or ground off to matzh the contours of the castings,
after which the castings are shot blasted to remove remaining mold
sand and scale.
4/81 Metallurgical Industry 7.10-3
-------
TABLE 7.10-1. EMISSION FACTORS FDR CRAY IRON FURNACES3
EMISSION FACTOR RATING: B
o
1
w
V.
iSi
o
z
•n
o
H
O
Tut itculnlr.s Carbon Monoxide Sulfur Dioxide Nlrrngrn Oxide* VOC U-ad
Furniirp Type '"'./If, Ih/tun kg/Mg Ibi'tnn kg/Hg Ib/ton kg/Hg Ib/ton kg/Hg Ib/ron kg/Hg Ib/ton
c,d
Cupci La
Uncontrolled fl.5 17 145f 73f 0. 6S8 1.25S8 - - 0.05-0.6 O.l-l.l
O-I7)8 (5-34)C
Wpt rap 48--- - - .__ _ _
InplnKfuc Jt Hcrubb«r 2.5 5--- -____ _.
High energy scrubber 0.4 0.8 - - O.JS* O.A5* - - -
Electrost/ittc prpclpttator 0.1 O.ft - - _ _ _ _ _ __
Rag rm<-r O.I O.Z --_ _..__ _ _
(J-10) (V20)
Klfrtrlr Induction
KPVP rhpmt ury
ncg
neg
.OOfr-.C7 .U1Z-O.U
Expressed A3 weight of pollutant p«r weight of gray Iron produced. He& - negligible,
^References ii and 9-12.
.References ?-5.
o
Apprixlmat"ly 851 "T the tornl charge Is i-et/1. For every unit wc>|iht of coke In the charge, 7 ijr»lirt -'[ gray Iron j?e produced.
Vn\iie.s In p.irenl1ieaea revrfcneot tlie range of expected values.
Reference G.
^Reference 1. 5 represent* I sulfur In Che coke. Thin factor aeau«ea 101 of the sultui In converted tii SO .
H^ferrnces I and 6.
-------
TAULE 7.10-2. MISSION FACTORS FOR FUGITIVE PARTICULARS FROM GRAY IRON FOUNDRIES*
.MISSION FACTOR RATING: D
• — - "—
Emissions
7
r*
C
n
to
H-
£
M
Q.
B
*
Proce "»s
Scrap and Charge Handling,
Heat Ing b
MagmvsliiH Treatment
innocula tlon
Pouring
Cooling
Shakeout
(-,
Cleaning, Finishing
Sand Hamiling, Preparation,
Hulling6
Got.: Making, Baking
kg/Mg
0.3
^.5
1.5 - 2.5
2.5
5
16
8.5
70
0.6
Ib/ton
0.6
5
3-5
5
10
32
17
40
1. 1
Emitted to
Work Znvlronment
kg
U
2
2
4
6
0
13
0
/*
.25
.5
_
.5
.5
.5
.15
.6
Ib/ton
0.5
5
_
5
9
13
0.3
26
1. 1
En It ted to
Atmosphere
kg/Kg Ib/ton
0.
0.
_
I
0.
0.
0.
I.
0.
1
5
5
5
05
5
6
0.
I
_
2
1
I
0.
1
I.
2
L
1
^Expressed aa might of pollutant per welp.nl of metal melted.
Reference I. p. 111-13.
Reference 7, p. 2-83.
-------
7.10.2 Emissions and Controls
Emissions from the raw materials handling operations consist
of fugitive participates generated from the receiving, unloading,
storage and conveying of all law materials for the foundry. These
emissions are controlled by enclosing the major emission points and
routing the air fror the enclosures through fabric filters or wet
collectors.
Scrap preparation using heat will emit smoke, organics and
carbon monoxide, and preparation i,ping solwnt ctegreasers viil.1 emit
organics. (See Section 4.6, Solvent Decreasing.) Catalyri.c incinera-
tors and afterburners can be applied to control about 05 percent of
the erganic_s and carboi t,,onoxide.
Emissions from melting furnaces consist of particulates,
carbon monoxide, organics, sulfur dioxide, nitrogen oxides and
small quantities of chlorides and fluorides. The partlculat.es,
chlorides and fluorides are generated by flux, incomplete combustion
of coke, carbon additives, and dirt and scale on the scrap charge.
Organics on the scrap and the reactivity of the coke effect carbon
monoxide emissions. Sulfur dioxide emissions, characteristic of
cupola furnaces, are attributable to sulfur in the coke.
The. highest concentration of furnace emissions occurs during
charging, backcharging, alloying, slag removal, and tapping opera-
tions, when the furnace lids and doors are o^ned. Generally,
these emissions have escaped into tne furnace building and have
been vented through roof vents. Controls for emissions during the
melting and refining operations usually concern venting the furnace
gases and fumes directly to a collection ard control system.
Controls for fugitive furnace emissions involve the use of roof
hoods or special hoods in the proximity of the furnace doors, and
of tapping ladles to capture emissions and to route them to emlssioi
control systems.
High energy scrubbers and bag filters with respective effi-
ciencies greater than 95 percent and 98 percent arc used to ooitrcl
particulate emissions from cupolas and electric t.'c furnaces in the
U.S. Afterburners achievlrg 95 fercent control are used for reducing
organics and carbon monoxide emissions f'.om cupolas. Normally
induction furnaces are uncontrolled.
The najor pollutants from mold and core production are particu-
lates from sand reclaiming, sand preparation, sand mixing with
binders and additives, and mold and core forming. There are organics,
CO and particulate emissions fron, core baking, and organic emissior.s
from mold drying. Bag filters and high energy scrubbers can be
used to control particulates from mold and core production.
Afterburners and catalytic incinerators can be used to control
organics and carbon raonoxio" emissions.
7.10-0 EMISSION FACTORS 4/81
-------
TABLE 7.10-3. SIZE DISTRIBUTION FOR PARTICULATE EMISSIONS FROrt
THREE ELECTRIC ARC FURNACE INSTALLATIONS
Particle Size (u)
68
98
Foundry B
8
5't
8V,
89
93
96
99
Foundry C
18
61
84
91
94
96
99
SReference I, p. 111-39.
TABLE 7-10-4. SIZE DISTRIBUTION FOR PARTICULATE
EMISSIONS FROM EIGHTEEN CUPOLA FURNACE INSTALLATIONS8
Cumulative % Less
Particle Size (^) Than Indicated Size
<2
<5
<10
<20
<50
-------
In the casting operations, large quantities of particulates
can be generated in the treating and innoculation steps beforu
pouring. Emissions from pouring consist of fumes, carbon morv-xtde,
arganics. and particulates evolved from the tiold and core material:.
when contacted with molten iron. These emisa'.cns continue to
evolve as the nold conls. A significant quantity of pirticulate
emissions is also generated during the carting siiakeoat operation.
Particulate emissions from ehakeout can be controlled by either
high energy scrubbers or bag filters. Emissions Frrnn poi.ii. Ing ar«
normally uncontrolled or are ducted into other exhe.us'. streams.
Emissions from finishing operations are cf large particulars
emitted during the removal of burrs, risers and gates, and during
the blasting process. Parr iculate.s from finishing operations are
usually large '.n size and are easily controlled by cyclones.
Emission factors for melting furnaces are presented in
Table 7.10-1, and emission factors for fugitive particulates are
presented in Table 7.10-2. Typical particle site distributions for
emissions from electric fire, and cupola furnaces ar
-------
8. P.P. Fenncilly and P.D, Sp.iwn, Mr Pollutant Coivtjrol Techniques
for Electric Arc FurnacesIn the Iron and Steel Foundry ^Industry,
EPA 450/2-78-024, U.S. Environmental ProUction Agoncy, Research
Triangle Park, ^, June 1978.
9. Control Techn iques f.-.t I mad Air E-iii ss ions, Volumes 1 and 2,
EPA-450/2-77-012, U.S. Environmental Protection Agency, Research
Triangle Park, NC. December 1977.
10. W.E. Davis, Emissions Study of Industrial Sources of lead Air
Pollutants, 1970. AP1D-1543, U.S. Environmental Protection
Agency, Rpsearch Triangle Park, NC, April 1973.
11. Emission Test No. 71-CI-i,, Office cf Air Quality Planning anj
Standards, U.S. Environmental Prote-.tioa Agency, Research
Triangle Park, NC, February 1972.
12. Emission Test No. 71-CI-30, Office of Air Quality Planning
and Standards, U.S. Environmental Protection Agency, Research
Triangle Park, NC, March 19/2.
4/81 Metallurgical Industry 7.1Q-9
-------
7.11 SECONDARY LEAD PROCESSING
7.11.1 Process Description
The secondary lead industry processes a variety of leadbearing
scrap and residue to produce lead and lead alloy ingots, battery lead
oxide, and lead pigments (Pb30L, and PbO). Processing may involve scrap
pretreatment, smelting and lefining/casting. Processes typically used
in each operation are shown in Figure 7.11-1.
7.11.J..1 Scrap pretreatroent is the partial removal of metal and non-
metal ontaminants from leadbearing scrap and residue. Processes used
for scrap pretreatment include battery breaking, crushing and sweating.
Battery breaking is the draining and crushing of batteries followed by
'ranual screening to separate the lead from nonratstallic materials. This
separated lead scrap is then mixed w?th other scraps and smelted in
.reverberatory or blast furnaces. Oversize pieces of scrap and residues
are usually crushed by jaw crushers. Sweating separates lead from high-
melting metals in direct gas or oil fired rotary or reverberatory
furnaces. Rotary furnaces are typically used to process low lead content
acrap and residue, while reverberatory furnaces are used to process high
lead content scrap. The partially purified lead is periodically tapped
for further processing in smelting furnaces cr pot furnaces.
7.11 1.2 Smelting is the production of purified lead by meltirg and
separating lead from metal and nonraetallic contaminant:: and by reducing
oxides to elemt-.ital lend. Reverberatory smelting furnaces are used to
produce a semisoft lead product that typically contains 3--i percent
an^iuony. Blast furnaces prcduce hare' or antimonial lead containing
about 10 percent antimony.
A reverberatory furnace produces spmisoft lead from a charge of
lead scrap, metallic battery parts, oxides, drosses and other residues.
The furnace consists of a rectangular shell lined with refractory brick
and fired directly with oil or gas to a temperature of 2300°F (1250°C).
The material to be melted is heated by d.'.rect contact with combustion
gases. The furnace can process aoout 30 tons per day (45 MT/day).
About 47 percent of the charge is typically recovered as lead product
and is periodically tapped into molds or holding pots. Forty-six
percent of the charge is removed as slag and subsequently processed in
blast furnaces. The remaining 7 percent of the furnace charge escapes
as dust or fume.
Blast furnaces produce hard lead from charges containing siliceous
slag from previous runs (typically about 4.5 percent of the charge),
scrap iron (about 4.5 percent), limestone (abouu 3 percent), coke (about
5.5 percent), and oxides, pot furnace refining crosses, and reverheratory
slag (comprising the remaining 82.5 perrent of the charge). The propor-
tions of rerun sJ.ags, limestone and coke vary respectively to as high as
8 percent, 10 percent, and 3 percent of the charge. Processing capacity
of the blast furnace ranges from 20 - RO tons per day '18 - 73 Mr/day).
10/80 Met.all'irp.ical Industr, 7.11-1
-------
Similar ro iron cupolas, the furnaces consist of vertical sceel cyl-
inders lined with refractory brick. Combustion air at 0.5 - 0.75 psig
is introduced at the bottom of the furnace through tuyeres. J noe of the
coke combusts to melt the charge, while the remainder reduces lead
oxides to elemental lead. The furnace exhausts at temperatures of
12"0 - 1350°F (650 - 730°C).
As the lead charge molts, limestone and iron float to the top of
the molten bath and form a flux tnat retards oxidation of the product
lead. The molten lead flows from the furnace into a holding pot at a
nearly continuous rate. The product lead -.onstitu*-.t.3 roughly 70 percent
of the charge. From the holding pot, the lead is usually cast into
large ingots, called pigt. or sows.
About 18 percent of the charge is -ecovered as slag, with about 60
percent jf this being a sulfurous slag called matte. Roughly 5 percent
of the charge la retained for reuse, and the remaining 7 percent of the
charge escapes aa dust or fume.
7.11.1.3 Refining/casting is the use of kettle type furnaces in remelt-
dng, alloying, refining and oxidizing processes. Materials charged for
remelting are usually lead alloy ingots which require no further process-
ing before casting. The furnaces used for alloying, refining and oxidiz-
ing are usually gas fired, and operating temperatures rc..ge from
700 - 900°F (375 - 485°C).
Alloying furnaces simply melt and mix ingots of lead and alloy
material. Antimony, tin, arsenic, copper and nickel are the most common
alloying materials.
Refining furnaces remove copper and anff.ncny to produce soft lead,
and they remove arsenic, copper and nickel to produce bard lead. Sulfur
may be udded to the molten lead bath to remove copper. Copper sulfide
skimmed oil as dross may subsequently be processed in a blast furnace to
recover residual lead. Aluminum chloride flux may be used to remove
copper, antimony and nickel. The antimony content can be reduced to
about 0.02 percent by bubbling air through the molten lead. Residual
antiiuony can be removed by adding sodium titrate and sodium hydroxide to
the bath and skimming off the resulting dross. Dry dressing consists of
adding sawdust to the agitated mass of molten net?-!. The sawdust
supplies carbon to help separate globules of leaa suspended in the dr- -s
and to reduce some of the lead oxict?. to elemental lead.
Oxidizing furnaces are eithei l.ettle or raverLoratory funiacee
which oxidize lead and entrain the product lead oxidat in the combust;on
air stream. The product is subsequently recovered in baghouses at high
efficiency.
7-11-2 EMISSION FACTORS 10/80
-------
7.11.2 Emissions and Controls p'3
ivnission factors for uncontrolled processes ai.d fugitive partic-
ulace emissions are in Tables 7.11-1 and 7.11-2, respectively.
Reverberaiory and blast furnaces account for .about 88 percent of
the total lead emissions from the secondary lead iudustry. Most of the
remaining procs-ses are small emission sources with undefined emission
characteristics.
Emissions from battery breaking mainly consist of sulfuric acid
mist and dusts containing Hirt, battery case material and lead com-
pounds. Emissions from crushing are also mainly dusts.
Emissions from sweating operations consist of fume, dusc, soot
particulates t.id combustion products, including sulfur dioxide. The
sulfur dioxide emissions are from the combustion of sulfur compounds in
the scrap and fuel. Dusts range in si::e from 5-20 urn, while unagglora-
erated lead fumes range, in size from 0.07 - 0.4 um, with an average
diameter of 0.3 yra. Particulate loadings in the stack gas from rever-
beratory sweating range from 1.4 - 4.5 grains per cubic foot (3.2 - 10.3
g/m^). Baghouses usually control swearing emissions, with removal
efficiencies exceeding 99 percent. The emission factors for l«?ad sweat-
ing in Table 7.11-1 are lased on measurements at similar sweating furnaces
in other secondary metals processing industries, and are not bas=d on
measurements at lead sweating furnaces.
Heverberatory smelting furnaces emit particulates and oxides of
sulfur and nitrogen. P^rticulates consist of oxides, sulfides and
sr.lfates of lead, antimony, arsenic, copper and tin, as well as unagglora-
erated lead fume. Pmticuiate loadings range from 7-22 Drains per
cubic foot (16 - 50 g/m3). Emissions are generally controlled with
settling and cooling chambers followed by a baghouse. Control efficien-
cies generally exceed 99 percent, as showr> ir Table 7.11-3. Wet scrub-
bers are sometimes used to reduce sulfur dioxide emissions. However,
because of the swall particles emitted, scrubbers are not as widely used
as baghouses tor particulate control.
Two chemical analyses by electron speclroscopy showed the part-
iculat.es to consist of 38 - 42 percent lead, 20 - 30 percent tin, and
about 1 percent zinc.1& Typlcall", particulates from rtverberatory
snielting furnaces comprise about 20 percent lead.
Kmiosions from blast furnaces occur at charging doors, the slag
tap, the lead well, and the furnace stack. The emissions are combustion
gases (includinp, carbon monoxide, hydrocarbons, and oxides of sulfur and
nitrogen) and p.-.rticulates. Emissions from the charging doors and the
slag tap are huuded and routed to the devices treating the furnace stack
emissions. Reverbera_ury furnace particulates are larger than those
emittf:i ^r;-(n blast furnaces and are thus suitable for control by scrubbers
.10/'JO Metallurgical Industry 7.1L-J
-------
PRETHEATMENT
SMELTING
REFINING/CASTING
O
CJ
O
BATTERIES
m BATTLRY
BREAKING
ESI DUES ,
CRAP -»l nfliisi.'iNr,
HJIL
11 F SFH4P f
THEO I ROTARY/TUBE
WIRE — «-j SWEATING
*UEL
t
„ REVERBFRATDRY
SCRAP 1- SWEATING
i
OXIDES, FLUE DUSTS.
MIXED SCRAP
PURE SCRAP
BLASTICUPOLAI
FURNACE SMELTING
ALIUYING
FLUX AGENT
FUEL 1
_pj KETTLEIALLOVING)
I REFINING
FUEL
AIR
t
KETTLE
OXIDATION
FUEL
1 AIR
RFVERBERATORV
OXIDATION
Figure 7.11 -1. Flow scheme of secondary lead processing.^
-------
Tablt 7.11-2.
FUGITIVE EMISSION TACTORS FOTi SECONDARY LEAD PROCESSING
MISSION FACTOR RATING: E
Parciculateaa
Source
Sweating
Smelting
Kettle
Refining
Casting0
Ib/ton
1.6 - 3.5
2.8 - 15.7
0.04
0.88
kg/MT
0.8 - 1.8
1.4 - 7.9
0.02
0.44
Leadb
Ib/ton kg/MT
0.4 - 1.8 0.2 - 0.'»
0.6 - j.6 0.3 - 1.8
0.01 0.005
0.2 0.1
a
of the uncontrolled stack emissions. All factors except that for
casting are based on the amount of change to the process. The casting
.factor is based on the amount of lead cast. Reference 14.
Factors are based or. aa approximation that- partlculate emissions
contain 23% lead. Referenceb 3 and 5.
cFcctors based on limited tests of a roof monitor over casting operations
at a primary smelter.
10/80
Metallurgical Industry
7.11-5
-------
or fr.br ic filters downstream of coolers. Efficiencies for various
crntrol devices are shown in Table 7.11-3. In one application, fabric
Cil'-ers alone captured over 99 percent of the blast furnace parrlculate
emissions.
Table 7.11-3. EFFICIENCIES OF PARTICIPATE CONTROL EQUIFME1TT
AfSOCIAlKD WITH SECONDARY LEAD SMELTING FURNACES
Control devtcf
Furnace
type
Particulate control
efficiency, %
a
b
.d
Blast
Reverberatory
Blast
Reverberat-«ry
Revc-rberatory
Blast
98.4
99.2
99.0
9S.7
99.8
99.3
Fabric filter
Dry cyclone plus fabric filter
Wet cyclone plus fabric filter
Settling chamber plus dry
cyclone plus fabric filter
Viinturi scrubber plus demiscer^
, Reference 8.
Reference 9.
Reference 10.
Reference 12.
The size distribution for blast furnace pan. julates recovered by
an efficient fabiic filter is reported in Table 7.11-4. Particulates
recovered from another blast f'irnace contained about 80 - 85 percent
lead sulfate and lead chloride, 4 percent tin, 1 percent cadmium, 1
percent zinc, 0.5 percent each antimony and arsenic, and less Chan 1
percent organic matter.
17
Kettle fu:naces for melting, refining and alloying are relatively
minor emission sources. The kettles are hooded, with fumes and dusts
typically vented to baghouscs and recovered with efficiencies exceeding
99 percent. Twenty measurements r-f the uncontrolled particulates from
kettle furnaces showed a mass median aerodynamic particle diameter of
18.9 urn, with part-.icle i.ize ranging irom 0.05 - 150 pm. Three chemical
analyses by electron spectroscopy showed the composition of particulates
to vary from 12-17 percent lead, 5-17 percent tin, and 0.9 - 5.7
percent zinc.
16
Emissions from oxidizing furnaces are economically recovered with
baghousts. The particulates are mostly lead oxide,, but they also
contain amounts of lead and other metals. The oxides range in size from
0.2 - 0.5 VJID. Controlled emissions have been reported to be as low as
0.2 - 2.8 pounds per tnn (O.I - 1.4 Kg/MT).
7.11-6
EMISSION FACTORS
10/80
-------
dr..
O
Table 7.11-1. EMISSION FACTORS ?UR SECONDARY LEAD PROCESSING3
Source
15.) t f. i "Y hre.ikini.;
h
Swe.it in-.
s u, lL.,,ini,h
!7 d
£ Smelt me.
c Rever >er;itorv
M ij
OS rfl;is!. (<•. -,.ii." '
H-
2 Kettle refining
nx idji ion
3 Kettle
a.
P.irt ieulati'S I.e.id
Ih/ton ktj/MT Jr., ton kg/Ml'
NA NA N/, NA
SA NA NA MA
,.•-70 l&'^'i 7- if/' 4-J°
147 f>6-3i'3)1 74 (28-IS7)e 34 (U-72)r 17 (6-lf>)'"
I9J (.'I-',"'.'1 97 (11-191)' 44 (-VSH)*" 'I'l (?-44)C
n.8(1 o.-.8 n.2c o.ic
-.40 ' -701 NA NA
KA ^ A NA NA
SuJTur Dinxide Emis.sinn F.i,'
IS/ ton k^/MT K.,1 (-IK
NA MA
NA NA
".i\ KA K
Ne); Neg
80 (7I-88)1 40 H6-44)1' B
'>) (18 110)' LI (9-S^)1 B
N'A r;.' h
NA NA r
KA NA
All emission t.inors .in: h,-iseu up. t!ie qu; 'tity "I mater al charged to rh< furnace (except part irulctp kitili oxidation).
!>.V = datn int aval ' .:Me. Npp. - n<->',I igible .
l' Hefercr,,e I .
tmisslon farter rating ot K. Fmission factors Tor lead omissions artf based on an approximation that p;irt icu i.itt.* emissions cnntair .'J.''
. leid. Keferi>r.i-es 1 arrfj ").
Numl.ers in parenttifses represent r-'ini'ps <>l values ohiuined.
1 Ke'"er« nc'"-. R - 11.
ReTercn.es li n.
^ Re feren< e 1! .
. helerences I jnc' ?.
f.t -I'nHallv all of tlio product Ip.id oxide i •; entrained in .in air stream and subsequent ly recovered by a h.i^hi use wit'i .iverape collection
» T f ic ; t.':u : es in excess nl 99/^. Tde reporteJ v;ilu. re] resentK pmifisinns of lead oxide tb'il osc.ii-*1 .1 h.ifchotiso \i*'n*r>t I o colled I he-
lead ox.de |)(od<,cl. The emi?. ion (.n-lor is hiisiV on thf amount of Ie;id oxid" produced and rep-•'F.ent s .in ;ipprr>v : i.ic e upper limit (or
iirr is si.'(is.
-------
Table 7.11-4. PARTICLE SIZE DISTRIBUTION OF PARTICULATEa
RECOVERED FROK. A COMBINED BLAST AND REVERBERATORY
FURNACE CAS STREAM WITH BAGHOUSE CONTROL*
Particle Size Range, urn FaLric filter catch, vt %
0 CO
1 to
2 to
:* to
4 to
1
2
3
4
16
13.
t-5.
19.
14.
8.
3
2
1
0
4
Reference 4, Table 86.
References for Section 7.11
1. William n, Coltharp, et_ajl., Multimedia Environmental Assessment
of the Secondary Nonferrous Metal Industry (Draft), 2 Volumes,
Contract No. 68-02-1319, Radian Corporation, Austin, TX, June 1976.
2. H. Nack, et al., Development of an Approach to Identification of
Emerging Technology and Demonstration Opportunities, EPA-650/2-74-
048, U.S. Environmental Protection Agency, Research Triangle Park,
NC, May 1974.
3. J. M. Zoller, £t_al^, A Method of Characterization and Quantifi-
ca_tion of Fugitive Lead Emissions from Secondary Lead Smelters,
Ferroalloy Plants and Gray~Iron Foundries (Revised), EPA-450/3-78-
003 (Revised), U.S. Environmental Protection Agency, Research
Triangle Park, NC, August 1978.
4. John A. Danielson, editor, Air Pollution Engineering Manual, Second
Edition, AP-40, U.S. Environmental Protection Agency, Research
Triangle Park, NC, May 2973, pp. 299-304. Out of Print.
5. Control Techniques for Lead Air Emissions, EPA-450/2-77-012, U.S.
Environmental Protection Agency, Research Triangle Park, NC,
January 1978.
6. Background Information for Proposed New Source Performance Standards,
Volume I; Secondary LeadSmelters and Refineries, APTD-1352, U.S.
Environmental Protection Agency, Research Triangle Park, NC, June
1973.
7.11-8 EMISSION FACTORS 10/80
-------
7. J. W. Watson and K. J. Brooks, A Review of Standards of Performance
for New Stationary Sources - Secondary Lead Smelters (Drait), EPA
Contract No. 68-02-2526, The Mitre Corporation, McLean, VA, June
1978.
8. John E. Williamson, et al., A Study of Five Source Teats on Emissions
from Secondary Lead Smelters. EPA Order No. 2PO-68-02-3326, County
of Los Angeles Air Pollution Control District, Los Angeles, CA,
February 1972.
9. Emission Test No. 72-CI-8, Oft ice of Air Quality Planning and
Standards, U.S. Environmental Protection Agency, Reseavch Trianglu
Park, NC, July 1972.
TO. Emission Test No. 72-CI-7, Office of Air Quality Planning and
Standards, U.S. Environmental Prot2c-.ion Agency, Research Triangle
Park, NC, August 1972.
11. A. E. Vandergrift, et al., Particulate Pollutant Systems Study,
Volume I: Mass Emissions. APTD-0743, U.S. Environmental Protection
Agency, Research Triangle Park, NC, May 1^71.
12. Emission Test No. 71-CI-33, Office of Air Quality Planning and
Ftandai.ds, U.S. Environmental Protection Agency, Research Triangle
Park, NC. August 1972.
13. Emission TCS,: No. 71-CI-34, Office of Air Quality Planning and
Standards, U.S. Environmental Protection Agei:cy, Research Triangle
Park, NC, July 1972.
14. Technical Guidance for Control of Industrial^ Process Fugitive
Particular Emissions, EPA-450/3-77-010, U.S. Environmental
Protection Agency, Research Triangle Park, NC, March 1977.
15. Silver Va_l]e\ /Bunker Hill Smelter Environmental Investigation
(Interim Report). EPA Contract N7o. 68-02-1343, PEECu-En. Ironmental
Specialists, inc., Cincinnati, OH, February 1975.
16. E I. Hartt, An Evaluation uf Continuous Parriculcte Monitors at a
Secondary Lend Smelter, M.S. Report No. O.K.-16, Environmental
Protection Service, Environment Canada.
17. J- E. Howes, e_t al., Evaluation of Stationary Source PartIcul.itfc
Measurement Methods, VolumeV: Secondary Lead Smelters, EPA Contract
No. 68-02-0609, Battelle Columbus Laboratories, Cclumbus, OH,
January 1979.
10/8C M~ta] 1 irs;-:.cal Industry 7.11-9
-------
7.12 SECONDARY MAGNESIUM SMELTING
7.12.1 Process Description1
Magnesium smelting is curried out in crucible or pel-type .''urrwces ;hat .ire charged with magnesium scrap
and fired by gas, oil, ur e'ectric heuiing. A flux is n^d to c^vcr th* sua'ace of the niolien metal because
magnesium will bum m ajr at the pouring temperuluri: (upproxjmutLly 1500 r or KI5°C). The moiicn
n\ii)uicsiuni, usually cast hy pxniriiig into molds, is •jimealed in oven., utilising an aimciphert1 devou' of oxygen.
7.12.2 Emissions'
Emissions tiom magnesium smelting include particulate magn.'sium (l.ij-Ol from the melting, m.rugeii oxides
from the fixation o< atmospheric nurogen by the furnace icmperuturos.iind suitur djoxido losses from annealing
oven atmospheres. Factors affecting emissions include the capacity of ilic furnace; the type ol (lux used on the
molten material, the amount of lancing used; the amount of contamination ol' the scrap, j'dudi'ig oil and other
hydrocarbons; and the type and extent of con'rol equipment uscJ on the process. T!ie emission factors for a pot
furnace arc shown in Table 7,1 2-1.
Table 7.12-1. EMISSION FACTORS
FOR MAGNESIUM SMELTING
EMISSION FACTOR RATING: C
Tyoe of turnace
Pot fu. nace
Uncontrolled
Controlled
Paniculaus"
Ib/ton
4
0.4
kg/MT
2
0.2
BRel»rerues 2 and 2. (Emission
f. .pressed at units pt'r u. il weight of
metal processed.
2/72 MetallHp-kol ludtislry 7.12-1
-------
References for Section 7.1 2
I. Aif Polluiant Emission Factors. Final Report. Resources Research, Inc. Reston, Va. Prepared for National
Air Pollution Tontrol Administration, Durham, N.C., under Contract Number C?A-22-69-l 19. April 1970.
2. Allen, C. L. ot a). Control of Metallurgical ar d Mineral Dusts and Fumes in Los Angeles County. Department
of the Intencr, Bureau of Mjnes. Washington, D.C. Information Cucular Number 7627. April 1952,
3. Hammon-i, W. F. D?ta on Nor-Ferrous Me* liturgical Operations. Los Angeles County Ail Pollution Con.ml
District, November 1966.
7.12-2 EMISSION FACTORS 2/72
-------
7.13 STEEL FOUNDRIES
7.13.1 Process Description
Steel foundries produce steel castings by the melting, alloying
and molding of pig iron and steel scrap. The process flow diagram
of a typical steel foundry is presented in Figure 7.13-1. The
major processing operations of the typical steel foundry are raw
materials handling, metal melting, mold and core production, and
casting and finishing.
Raw Materials Handling - The raw material handling operations
include the receiving, unloading, storage and conveying of all raw
materials for the foundry. Some of the raw materials used by steel
foundries are pig iron, iron and steel ecrap, foundry returns,
metal turnings, alloys, carbon additives, fluxes (limestone, soda
ash, fluorspar, calcium carbide), sand, sand additives, and binders.
These raw materials are received in ships, railcars, trucks, and
containers, and are transferred by trucks, loaders, and conveyors
to both open pile and enclosed storage areas. Thry are then
transferred by similar means from storage ;o the subsequent processes,
Melting - Generally, the first step in the metal melting
operations is scrap preparation. Sincj scrap is normally purchased
in the proper size for furnace feed, preparation primarily consists
of sr.rap degreasing. This is very important for Hlectric induction
furnaces, as organics on scrap can be explosive. Scrap may be
degreased with solvents, by centrifugal ion or by incinerator or
preheater combustion. After preparation, the scrap, metal, alloy,
and flux are weighed and charged to the furnace.
Electric arc furnaces are i'.sed almost exclusively in the steel
foundry for melting and formulating steel. Electric arc furnaces
are larga refractory lined steel pots, fitted with a refractory
roof through which three graphite electrodes are inserted. The
metal charge is tuelted with resistive heating generated by electrical.
current flowing among the electrodes and thiough the charge.
Electric arc furnaces are charged with raw materials by removing
the lid, through a chuy.e opening in the lid, or through a door in
the side. The molten metal is tapped by tilt tag and pouring
through a hole in the side. Melting Capacities range up to
10 megagrams (11 tons) per hear.
A second, iesj common, furnace used in '-t<. el foundries is thp
opev. hearth furnace, a very laige shallow rcfrcctory lined vessel
whlc'i. ip operated in & batch manner. The open hecrth furnace is
fired at alternate ends, using the heat from the waste combustion
gases to heat the incoming combustion air.
A third furnace used in the steel foundry is the Induction
furnace. Induction furnaces are vertical refractory lined cylinders
4/81 Metallurgical Industry 7.13-1
-------
FUGITIVE
oust
*
RAW MATERIALS
UNLDADIMG, STORAGE,
TRANSFER
• HUX
• METALLICS
• CARBON SOURCES
• SAND
• BINDER
SCRAP
PREPARATiON
FUMES AND* j
FUGITIVE <
DUST
r---*-FUGITIVE
CUST
AND SMOKE
tfENT
FURKANCE
• ELECTRIC ARC
• INDUCTION
•OTHER
, -"-FUGITIVE FUMES
i AND OUST
TAPPING,
TflEATtHB
1
MOLD POURING,
COOLING
'FUGITIVE FUMES
AND DUST
OVIM V'NT
SAND
CASTING
SNAKEOUT
LQOIING
LEANING,
FINISHING
» FUGITIVE
DUST
^ FUMES AND
FUGITIVE
OU2T
•FUGITIVE
DUST
SHIPPING
Figure 7.13-1. Typical flow diagram of a steei foundry.
7.13-2
EMISSION FACTORS
4/C1
-------
surrounded by electrical coils energized witn alternating current.
The resulting fluctuating magnetic field heats th^ metal. Induction
furnaces are kept closed except when charging, skimming and tapping.
fhe molten metal in tapped by tilting and pouring through a hole in
the side. Induction furnaces are also ujed with other furnaces, to
held and superheat a chargf. melted and refined in the other furnaces.
A very small fraction of the secondary steel industry also uses
crucible and pneumatic converter furnaces.
The basic melting process operations are 1) furnace charging,
in which 'octalv scrap, alloys, carbon, and flux pre added to the
furnace, 2) melting, during which th^ furnace remains close'',
'/"> backcharging, which is the addition of more metal and possibly
alloys, ^») refining, during which the carbon content is adjusted,
5) oxygen lancing, which is injecting oxygen into the molten steel
to dislodge slag ;t\\d to adjust the cht-mistry of the roet.il, 6) slag
remov?!, and ') tapping the- molten metal into a ladle or directly
into molds.
Mold and Core Production - Cores are forms used to make the internal
voids in castings, and molds are forms used to shape the casting
exterior. Cores are made of sand witK organic binders, molded into
a cote and baked in an oven. Molds are made of .vet sand with clay
and organic additives, dried with hot air. Increasingly, coal
setting binders are being used in both core and mold production.
Used sand from castings shakeout operations is recycled to the sand
preparation area, wheve it is cleaned, screened and reused.
Casting and Finishing - 'When the me 1'.ing process is complete, the
molten met.nl is tapped and poured into a ladle. At this time, the
molten metal may be treated by addiag alloys and/or other chemicals.
The feared metal is ..hen poured into molds and is allowed partially
to cool under carefully controlled conditions. Molten metal may be
poured directly from the furnace to the mold.
When partially cooled, the castings are placed on a vibrating
grid, and tho sand of thu mold and core are shaken away from the
casting. The sand is recycled to the mold manufacturing process,
and the casting is allowed to cool farther.
In the cleaning and finishing process, burrs, risers and gates
are broken or ground off to match the contour of the casting.
Afterward, the. castings are usually shot blasted to remove remaining
mold sap.d and scale.
7.13.2 emissions and Controls
Emissions from th« raw materials handling operations are
fugitive particulates generated from receiving, unloading, storage
and conveying all raw materials fur the foundry. These emissions
art controlled by enclosing the uajor emission points aid routing
the air from the enclosures through fabric filters.
4/81 Metallurgical Industry 7.13-3
-------
Emissions front scrap preparation consist of hydrocarboi _, if
solvent degreasing is used, and consist if smoke, organics anj
carbon monoxide if heating is used. Catalytic incinerators and
afterburners of approximately 95 percent control efficiency for
carbon monoxide and organics can be applied to these sources.
Emissions from melting furnaces are partic-ilates, carbon
tLonoxide, organics, sulfur dioxide, nitrogen oxides, and small
quantities of chlorides and fluorides. The particulates, chlorider.
and fluorides are generated by the flux, tne carbon additives, and
dirt and scale on the scrap charge. Organics on the scrap a \d the
carbon additives effect CO emissions. The highest concentrations
of furnace emissions occur during charging, backcharging, alloying,
oxygen lancing, slag removal, and tapping operations, when the
furnace ':ds and doors are opened. Characteristically, these
emissions have escaped into the furnace building an^ heve been
vented through roo* vents. Controls for emissions during the
melting and refining operations focus on venting the furnace gases
and fumes directly to an emission collection duct and control
system. Controls for fugitive furnace emissions involve either thii
une of building roof hoods or of special hoods near the furnace
doors, ro collect emissions and route them to emission control
systems. Emission control systems commonly useo to control partic-
ulate emissions from electric arc and Induction furnaces aro bag
filters, cyclones and venturi scrubbers. The capture
-------
TABLE 7.13-1. EMISSION FACTORS FOR STEEL FOUNDRIES
EMISSION FACTOR RATING: A
Particulatesa
Process kg/Mg Ib/ton
Nitrogen
oxides
kg/Mg Yb/ton
Melting
Electric arc°'c 6.5 (2 to 20) 13 (4 to 40) 0.1 0.2
Open hearthd'E 5.5 (1 to 10) .' I '.2 to 20) 0.005 0.01
f e
(.pen hearth oxygen lanced >e> 5 (4 to 5.5 i1 (8 to U)
Electric induction** 0.05 0.1 -
a
Expressed as units per unit weight ot metal processed. If the scrap metal
is very dirty or oily, or if increased oxygen lancing is employed, the
emission factor should be chosen from the high side of the factor range.
Electrostatic precipitator , 92 - 98% control efficiency; baghouse
(fabric filter), 98 - 99% control efficiency; ver.curi scrubber, 94 - 98%
control e
.References 2 - 10.
Electrostatic precipitator, 95 - 98. 5X control efficiency; baghouse, 99.9%
control efficiency; venturi scrubber, 96 - 99% control efficiency.
^References 2, 11 - 13.
Electrostatic precipitator, 95 - 98% control efficiency; baghouse, 99X control
efficiency; venturi scrubber, 95 - 98% control efficiency.
^References 6 anj 14.
Usually not controlled.
Emission factors for n.elting furnaces in the steel foundry are
presented in Table 7.13-1.
Although no emission factors are available for nonfurnace
emission sources in steel foundries, they are very similar to those
in iron foundries.1 Nonfurnace emission factors and particle size
distributions for iron foundry emission sources are presented in
Section 7.10. Gray Iron Foundries.
References for Section 7.13
). Paul F. Fennel ly and Peter D. Spawn, Air Pollutarit Control
Techniques for Electric Arc Furnaces in the Iron and _S_tee_l_
Foundry Industry, EPA-45Q/2- 78-024, U.S. Environmental
Protection Ag-.ncy, Research Triangle Par':, NC, June 1978.
4/81 Metallurgical Industry 7.13-5
-------
2. J.J. Schueneman, et a1.. Air Pollution Aspect a of the Iron and
Steel Industry, National Center for Air Pollution Control,
Cincinnati, OH, June 1963.
3. Foundry Air Pollution Control Manual, 2nd Ed., Foundry Air
Pollution Control Committee, Des Plaines, It, 1967.
. R.S. Coulter, "Smoke, Dust, Fumes Closely Controlled in Electric
Jurraces". lion Age. J_73:107-110, January 14, 1954.
5. Air Pollution Aspects if the Iron and Steel Industry, p. 109.
6. J.M. Kane and R.V. Sloan, "Fume Control Electrir. Melting
Furnaces", American Foundryman, _18j 33-34. November 1950.
7. Air Pollution Aspects of the Iron andSteel Industry, p. ]09.
8. C.A. Faist, "Electric Furnace Steel", Proceedings of the
American Institute of Mining antl Metallurgical Engineers,
_H_: 160-161, 195'3.
9. Air Poilution Aspects of the Iroa anJ Steel Industry, p. 109.
10. L.H. Douglas, "Direct Fume Extraction and Collection Applied
to a Fifteen Ton Arc Furnace", Special Report on Fume Arrestment,
Iron and Steel Institute, 1964, pp. 144, 14<».
11. Inventory of Air Contaminant Emissions, New York State Air
Pollution Control Board, Table Xi, p/. '4-19. Date unknown.
12. A.C. Ellioc ana A.J. Freniere, "Metallurgical Dust Collection
in Open Hearth and Sinter Plant", CanadianMining and Metal-
lurgical Bulletin. _55_(606): 724-732, October 1962.
13. r.L. Hemeon, "Air Pollution Problems of the Steel Industry",
JAPCA, _10(3): 208-218, March 1960.
14. J.W. Coy, Unpublished data, Resources Research, Incorporated,
Reston, VA.
7.13-6 EMISSION FACTORS 4/81
-------
7.14 E'^ONDARY ZINC PROCESSING
1 2
7.14.1 Process Description '
The secondary zinc industry processes obso/.cle and scrap
materials to recover zinc as slabs, dust and zinc oxide. Pro-
cessing involves three operations, .scrap pru treatment , melting and
refining. Processes typically used in each operation are shown in
Figure. 7.14-1. Molten product zinc may be used in zinc galvanizing.
Scrap Pretre?tment - Pretreatment is the partial removal of Tietal
anti other contaminants fiom scrap containing '.'.inc. Sweating
separates zinc froit 1'igh rielting metals and contaminants by melting
the zinc in kettle, rotary, reverberatory, muffle or electric
resistance furnaces. The j roduct zinc then is usually directly
ufed in melting, refining or alloying processes The high melting
residue is periodically raked from the furnace and further processed
CO recover zinc values. These residues may be processed by crushing/
screening to recover impure zinc or by sodium carbonate leaching to
oroduce zinc oxide.
In cr shing/acreening, zinc bearing residues are pulverized or
crusted to break the physical bonds between metallic zinc and
contaminants. The impure zinc is then separated in a screening or
ic classification step.
In sod.i<>m carbonate leaching, the zinc bearirg residue? are
converted r:> zinc oxide, which can be reduced to zinc metal. They
are crushed and wac'iei, to leach out zinc from contaminants. The
aqueous stream is then treated with sudium carbonate, precipitating
zinc as the hyJroxidr. or carbonate. The precipitate is then dried
and calcined to convert zin^ Hydroxide into crude zinc oxiut. The
ZnO product is usually refined f* zinc tt primary zinc smelters.
Melting -- Zinc- is melted at 425-590°C (800-1 100°F) in kettle,
crucible, reverberatory and electric induction furnaces. Zinc to
be melted may be in the form of ingots, reject castings, flashing
or scrap. Ingots, rejects and heavy scrap are generally melted
first, to provide a molten bath to which light scrap and flashing
are added. Before pouring, a flux is added and the hatch agitated
to separate the dross accumulating during the melting operation.
The flux floats the dross and conditions it so it can be skiitmed
from the surface. After skimming, the melt can be jvourRd into
molds or ladies.
Refining/Alloying - Additional processing steps may involve alloying,
distillation, distillation and oxidation, or reduction, Alloying
produces mainly zinc alloys from pretreated scrap. Often the
alloying operation is combined with sweating or melting.
Distillation retorts and furnaces are used to reclaim zinc
from alloys or to refine crude zinc. Retort distillation is the
4/31 Detail irgic;al industry 7.14-1
-------
w
o
n
H
O
70
v>
-IN
-v.
CD
DIE CAST
PRODUCTS
RESIDUES
SKIMMINGS
OTHER
MIXED
CLEAN
SCRAP
ZINC ALLOYS
CON [ANIMATED
ZINCOXIPF.
8AGHOUSE OUST
RESIDES
SKIMMINGS
PRETHEATMINT
-FUEI
REFINING/ALLOYING
ALLOYING AGENT
FUEL-, I ,-FLUII
~^"
-
-»
-»-
-•-
HEVERBERATORY
SWEATIN<;
r— FUEL
f
ROTARY
SWEATING
r-FUEl
MUFFLE
SWEATING
r-FUEl
-fc
h
!
-to.
1
XFTTLE1POT) 1
SWEATING [^
f-ELECTRiriTY
ELECTRIC
RESISTANCE
SWEATING
J
/SWEATEB\
Von WGOT>/
)
r
-
CRUSHING/
SCREENING
i
FL
•^
FL
Fl
h-»-
Fl
UI-j r-FUEL
KETTLE (POT)
MELTING
JX-J r-FUEl
CHUCWLE
MELTING
DX-, f-FUEL
REVERBERATORV
MELTING
-»•
'
1
H
ux ELECTRICITY
ELECTRIC 1
INDUCTION f-*^
MELTING 1
SODIUM
WATER-1 CARB.;HATE
f r / — \
SODIUM
CftRBONAIt
LEACHING
/ CRUOE \
\ OKIOE J
TO PRIMARY
SMELTERS
CARBO
r-
i
FUI
•*••
FUE
EL
H
FUE
rue
NMC
ALLOYING
L-j r-WATI
RETORT
OISTIILATION
li r"n
MUfFLE
3BTILLATION
, / ~WATI
1 GRAPHITE
ROD
DISTIL LATIOIV
,
R
h
R
R
••-
L-t r— AIR r-WATER
RETOHT
OISTILLATION
OXIDATION
L-i r-AIR r-*ATEIi
MUFFLE 1
OISTILLATION f*J
OXIDATION
INOXIDE
1 FUEl-i r-WATEH
RtTDRl
HtOUCTlUN
ALLOYS
ZINC
OXIDE
Figure 7.14-3 Process flow diagram of secondary zinc processing.
-------
TAbLE 7.14-1. UNCONTROLLED PARTICULAR EMISSION FACTORS
FOR SECONDARY 7,INC SMELTING0
EMISSION FACTOR RATING: C
Operation
Reverberatc-ry s\ eating
cle.Ml ac-tjlli; scrap
general Beta lie scrap
residual scrap
Rntsry sweat! igC
Muffl* sver.t.ngc
Kttlla atfci'.ing
clean neialllc scrip
general metallic scrap
Mldua? scrap
Electric icstcrance s.featlngc
Cruihinf/icreenlng
Sodlim carbonaca leaching
crushing/ screening1"
ca'clnlngd
K»'. tie (pot) melting
Crucible nelting
Reverbcratory selling
Electric Induction melting
Allaying
Retort and muffle distillation
f>ourlngc
ctxtlng .
auffle dljtillaiion
Graphite rod diillllaticn '
Rfcort dlstlllat ic-n/oxidat ion
Muffle disc illal lo'.i/uxieat un
Retort reduciion
Galvanizing
Iraissio
V.?/Mg
Nenllglbla
,.5
16
5.5-12.5
5.4-16
Negligible
S.5
12 .S
<3
C . 5-3 . 8
0.5-3. '.
IM.'J
0. CIS
.'HA
DNA
DMA
TNA
0.2-0.4
0. 1-0.2
.'2.5
Svjliglble
10-20
10-20
2">. 5
2.5
IS
P'/ton
•<^gliu proSuv'o-J . Thu
product tine oxid« Just -B totally carried ever ir. tie exhaust ?(-'-
from the furnace and is lecover.J with S8-99Z efficltncv.
4/31
Metallurgical Industry
7.14-3
-------
vaporization at 980-1250°C (1800-2280°F) oi elemental zinc with its
subsequent condensation as zinc dust or liq.iid zinc. Rapid cooling
of the vapor atreair below the zinc melting point produces zinc
dust, which can be removed from the condenser an4 packaged. If
slab >:inc is the desired product, the vg.pors .ire condensed slowly
at a higher temperature. The resultant melt is cast into ingots or
slabs. Muffle distillation furnaces pruduce principally zinc
ingots, and graphite rod resistance distillation produces zinc
dust ,
Retort ar-1 muffle furnace distillation and oxidation processes
produce zinc oxide dust. These processes are similar to distillation
through the vaporization step. In contrast, for distillation/oxi-
dation, thtf condenser is omitted, and the zinc vapor is discharged
directly into an air stream leading to a refractory lined combustion
chamber. Excess air is added to complete oxidation and to cool the
priiJuct. The zinc oxide product 1s usually collected in a baghouse.
ID retort reduction, zinc metal is produced by the reaction of
carbon monoxide and zinc oxide to yield zinc and carbon dioxide.
Carbon monoxide is supplied by the partial oxidation of the coke.
The zinc is recovered by condensation.
Zinc ualvanli'lng - Zinc galvanizing is the mating r>f clean oxide
free iron or stt.el with a thin layer of zinc by immersion in molten
zinc. The galvanizing occurs in a vat or In dip tanks containing
molten zinc ami cover flux.
7.14.2 Emissions and Controls '
Factors for uncontrolled point source z^i fugitive particulate
emissions are tabulated in Tables 7.14-1 and 7.LA-2 respectively.
Emissions from sweating and melting operations consist
principally of part icu5?'.es, zinc fumes, other volatile metals,
flux fumes and smoke generated by the incomplete combustion of
grease, rubber and plastics .n tSe zinc hi?.iring feed material .
Zinc furors are negligible at low furnace temperatures, for they
have A Low vapor pressure even at A80°C (900°F). With elevated
temperatures, however, heavy fuming can result. Flux emissions are.
minimized by the use of a nonfuning flux. Substantial emissions
may .irise from incomplete combust Lon of carbonaceous material in
the zinc scrap. These contaminants arf usually controlled by
afterburners. Further emissions are the products of combustion of
the fnrnact fuel. Since the •: jrnace fuel .' s usually natural gas,
these emissions are minor. In reverberatory furnaces, the products
of fuel conbust inn are ^mitteo with the other emissions. Other
furnaces er.it the fuel combust iori products as a separate emission
stream.
Particulates from sweating and melting ar« mainly hydrated
Zr.O, with small arr.ounc.J of carbonaceous material. Chemical
7.1'«-4 EMISSION FACTORS 4/81
-------
TABLE 7.14-2. FUGITIVE PARTICULATE UNCONTROLLED EMISSION
FACTORS FOR SECONDARY ZINC SMELTING
EMISSION FACTOR RATING: K
Particulate
Operation
Reverberatory sweating
b
Rotary sweating
Muffle sweating
Kettle (pot) sweating
Electric resistance .veating
Crushing/ screening
Sodium carbonate leaching
Kettle (pot) raeiting furnace
Crucible melting furnace
Roverbttratory melting furnace
Electric induction melting
Alloying retort distillation
Retort and muffle distillation
Casting
Graphite rod distillation
Retort distillation/oxidation
Muffle diatillatlon/oxidation
Retort reduction
kg/Mg
0.63
0.45
0.54
C.23
0.25
2.13
DNA
0.0025
0.0025
0.0025
0.0025
•HA
1.18
0.0075
DNA
UNA
DNA
DNA
Ib/ton
1.30
0.90
1.07
0.56
0.50
4.25
DNA
0.005
0.005
0.005
0.005
DNA
2.36
0.015
DNA
DNA
DNA
DHn
Reference 8. Expressed as units per end product, except factors
for crushing/screening and e^ctric resistance furnaces, which are
expressed as units per unit of scrap processed. DNA: Data not
.available.
Estimate based on stack enission factor given in Reference L,
assuming fugitive emissions to be equal to 5?! of stack emission?.
^Reference 1. Average of rsported emission factors.
Engineering judgement, assuming fugitive emissions from crucible
melting furnace to be equal to fugitive emissions from kettle
(pot) melting furnace.
4/81 Metallurgical Industry 7.14-5
-------
analyses of partlculate emissions from kettle sweat are shown in
Table 7.14-3.
TABLE 7.14-3. COMPOSITION OF PAJU^CULATE EMISSIONS
FROM KETTLE SWEAT PROCESSING3
Component Percent
ZnCl2 14. S - 15.3
ZnO 46.9 - 50.0
NH,C1 1.1 - 1.4
•4
A1203 1.0 - 2.7
Fe203 0.3 - 0.6
PbO 0.2
H20 (in ZnCl2 • 4^0) 7.7 - 8.1
Oxide of Mg, Sn, Nl, Si, Ca, Na 2.0
Carbonaceous material 10.0
Moisture (deliquescent) 5.2 - 10.2
Reference 3.
These particulates also contain Cu, Cd , Mn and Cr. Another
analysis showed the following composition: 4 percent ZnCl?. 77 percent
ZnO, 4 percent H2'3. 4 percent metal chlorides and 10 percent carbona-
ceous matter.^* Thqse particulates vary widely in size. Part iculates
from kettle sweating of residual zinc scrap hau the following size
distributions:
60% 0 - 10 u
177. 11 - 2CV
Particulates from kettle seating of metallic scrap had mean, part id e
size disi_ributionr ranging from Dptn * 1.1/u to DD^Q *' l-fe^.1 Emirsions
from a revcrberatory sweat furnace had an approximate
Baghouses aie most commonly used to recover piirticulate emissions
from sweating and melting. In one application on a nnjfflfi sweating
7.14-6 EMISSION FACTORS 4/81
-------
furnace, a cyclone and baghouse achieved paniculate recovery
efficiencies In excess of 99.7 percent. In another application on
a reverberatory sweating furnace, a baghouse removed 96.3 percent
of the partlculates, reducing the dust loading from 0.513 g/Nro3 to
0.02 g/Nm^. Baghouses show similar efficiencies in removing
participates flora exhaust gases of malting furnaces.
Crushing and screening operations are also suurces of dust
omissions. There particulars are composed of Zn, Al, Cu, Fe, Pb,
Cd, Sn and Cr, and they can ba recovered from hooded exhausts by
baghouses.
The sodium carbonate leaching rrocess produces particulate
emissions of ZnO dust during the calcining operation. This dust
can be recovered -"yelopment of an Approach to Identification
oi Emerging Technology and P monstr&tion Opportunities, FPA-650/
2-74-048, ''VS. Envi.onrueatal Protection Agency, Research
Triangle Park, NC, May 1974.
4/81 Metallurgical Industry 7.U-7
-------
5. G.L. Allen, °t al.. Control of Metallurgical anc'. Minsi'a^i Dusts
and Fumes in Los Angeles County, Nuab«r 7<>27, U.S. Department
of the Interior, Washington, DC, April 1952.
6. Restricting Dust and Sulfur DioxideEmissions from Lead Smelters,
translated from German, VDI Number 2235, *J,S. Department of
Health, Education and Welfare, Washington, DC, September 1961.
7. W.F. Hairmond, Data on Nanferrjus Metallurgical Operations, Los
Angeles Ccun«"' Air Pollution Control District, Los Angeles,
CA, November 196C.
8. Assessment of Fugitive Pa^tleulate Emission factorsfor
Industrla1 Processes, EPA-450/3-78-107, U.S. Environmental
Protection Agency, Research Triangle Park, NC, September 1978.
7.14-8 EMISSION FACTORS 4/81
-------
7.15 STORAGE BATTERY PRODUCTION
7.15.1 Process Description1
Lead acid storage batteries are produced from lead alloy ingots and lead
oxide. The lead oxide may be prepared by the battery manufacturer cr may be
purchased from a supplier. See Section 7.16.
Lead alloy ingots are charged to a melting pot, from which the molten
lead tlows into rolds that form the battery grids. Pasting machines force a
paste into the interstices or the grids, after which they are referred to as
plates. The grids are often c-u t in doublets anH split apart (slitting)
after tray have been pasted and cured. The Daste is. nude in a batch type
process. Mixing lead oxide powder, water and sulfuric acid produces a
positive paste, and the same ingredients in slightly different proportions
plus an expander (generally a mixture of bariura sulfate, carbon black and
make the negative paste.
After the plates are cured, they are sent to the three process operation
of plate stacking and burning and element assembly in the battery case.
Doublet plates are cut apart and stackeu in an alternating positive and
negative block formation, with insulators between Chen. These insulators ar?
of materials such as wood, treated paper, plastic or rubber. Then, in the
burning operation, leads are welded to tabs on each positive or negative
plate. An alternative to this operation is the cast-on strap process, in
which moltt-n lead is poured around the plate tabs to form the connection, and
positive and negative terminals ire then welded 1.0 each such connected
element. The completed elements are assembled in battery cases eithei before
(wet batteries) or after (dry batteries) the formation step.
Formation it the immersing of plates in a dilute sulfuric acid solution
and the connecting of positive plates to the vositive pole of a direct
rurrent (dc) source and the negative plates to the negative pole of the dc
source. In the wet formation process ,, this is done in the battery case.
Aftei roiming, the acid is dumped, fresh acid is added, and a boost charge is
applied to complete the battery. In dry formation, the individual plates may
be formed in tanks of sulfuric acid before assembly. Also, chey may be
assembled firsr and thtu formed in tanks. The formed elements fron either
method *re then placed in tne battery cases, and the batteries are shipped
dry. Figure 7.15-1 is n process flow diagram for lead acid battery
manufacture.
Defective parts are either recla'med at the battery plant or are sent to
a secondary lead smelter (See Section 7.11). Lead reclamation facilities at
battevy plants generally are small pot furnaces. 'Approximately 1 percent jf
the lead process. d at a typical lead acid battery plant is recycled thr^uRh
the reclamation operation .
Lead acid storage battery plants range in production capacity from less
than 500 batteries per day to about. 10,000 batteries per day. L
-------
C/J
Dl
n
H
o
1 PARTICIPATE i PARTICIPATE
J MATTER 'MATTER
LjEAO OXIPE I > EAO PASTE
fROOUCTIO* *1 MIXING
*
IPARIiC'JLATE
1 MATTER
\
PARTICULATE
. MOT TER
r- _ J. _, j_ „ -j
1
6PIO CASTINB ^ WID
"UP'.'ACE CASTING
. GRID 1 ' i PLATE PLATE fc ELEMENT ,_
PASTING I 1 STACK IMC gOftNINL ASSEMBLY
1
1
GRID CASTMG OPERATION THREE PROCESS OPERATION
ISULFURIC
IACD MI3T
RINSING
r~ TOULON |_ ANDWYINS
AGIO -f—*-
ASSEMBLY WTOI
* BATTERY CAStf \
\ ^ "ASM AW* _^, SHIPPING
1 PAINT
ACID MIST
FORMATION
ACID
REFILL
BOOST
CHARCE
—» PROCESS STREAM
--• ATM1SPMERIC EMISSION
STREAM
00
to
Figure 7.15-1. Process flow diacram for storage bat'TV production.
-------
TABLE 7,15-1. STORAGE BATTERY PRODUCTION EMISSION FACTORS*
Process
Grid casting
Paste mixing
Lr'ad oxide mill .
(baghouse outlet)
Thre? process operation
Lead reclaim ruruace0
d
Dry formation
Total production
Particular
kg(lb)/10J
batteries
1.42
(3.13)
1.96
(4.32)
0.05
(0.11)
42.0
(92.6)
3.03
(6.68)
14.7
(32.4)
63.2
(139)
Lead
kg(lb)/lG'
batteries
0.35
(0.77)
1.13
(2.49)
0.05
(0.11)
4.79
(1C. 6)
0.6?.
(1.38)
NA
6.94
(15.3)
Emission
Factor
Rating
B
D
C
B
B
B
References 1-7. NA • not applicable. Based on standard lutomotlve
batteries of about 11.8 kg (26 Ib) of lead, of which approximately half is
present in the iitad grids and half i.i the lead oxide pe^te. Particulate
emissions include lead and its compounds, ns well as other substances.
Lead emission factors are expressed as emissions of elemental lead.
Reference 5. Emissions measured for a well controlled facility (fabric
filters with an average airzcloth ratio of 3:1) were 0.025 kg (0.055 Ib)
particulate/1000 batteries and 0.024 kg (C.053 Ib) lead/1000 batteries.
Factors represent emissions from a facility with typical controls (fabric
filtration with an air:cloth ratio of about 4:1). Emissions from a
facility ;*ith typical controls are estimated to be about twice those from
a well controlled facility (Reference 1).
°Based on the assumption that about 1% of the lead processed at a typical
battery plant Is processed by the reclaim operation.
For sulfatts in aerosol form, expressed as sulfuric acid, and not account-
ing for water and other substances which might be present.
8/82
Metallurgical Industry
7.15-3
-------
battery contains about 11.8 kilograms (26 Ib) of lead, of which about h?lf is
present in the lead grids a.id half in Lhe lead oxide paste.
7.15.2 Emissions and Controls1"7
Lead oxide emissions result from the discharge of air used in the lead
oxide prcduction process. In addition, participate master and lead
particulate are generated in the grid ci-sting, paste mixing, lead reclamation,
three process operations, ana other operations such as slitting and sir.^11
parts casting. These particulates are usuallv collected by ventilation
systems to reduce employee exposure to airburnf iced. Sulfuric acid mist
emission^ arc generated during the formation step. Acid mist emis-sion-, are
significantly higher for dry formation processes than for wet formation
processes, because wet formation is conducted in battery cases, while dry
formation is conducted in open tanks. Table 7.15-1 presents average
uncontrolled emission factors for grid casting, paste mixing, lead reclamation,
dry formation, and il.ree process operations, and an average controlled
emission factor for l^ad oxide production. The perti.ulute emission factors
presented in the Table include lead and its compounds. The lead emission
factors represent emissions of lead in element and compound form, expressed
as elemental lead.
A. fabric filter is used as part of the process equipment to collect
product from the lead oxide facility. Typical air to cloth ratios of fabric
filters used for this facility are about 4 to 1. It is estimated thar.
emissions from a facility controlled by a fabric filter with a 3 to 1 nir to
cloth ratio are about 50 percent lesb than those from 9 facility with a
typical collection system.
Fabric filters can also be used to ^cucrjl emissions from slittiug and
three process operations. The paste mixing operation consists of two phases.
The firjt, in which dry ingredients are c.narK&d to the mixer, results in
major emissions of lead oxide and is usually vented Co a baghouse. For the
second phase of the cycle, when moisture is present in tne exhaust stream,
the paste mixer generally is vented to an impingement scrubber. Gria casting
machines are sometimes vented to an impingement scrubber. Lead reclamation
facilities genera] ly are also vented t-< impingement scrubbers.
Emission reductions of 99 percent and above can be obtained where fabric
filtration is used to control slitting, paste mixing and three process
operations. Application of scrubbers to paste mixing, grid casting ^nd lead
reclamation facilities can result in emission reductions from 6.5 percent tc
over 90 percent.
Wet formation processes usually do not require control. Emissions of
sulfuric acid mist from dry formation processes can be reduced by ever
95 percent with mist eliminators. Surface foaming agents are also used
commonly in dry formation baths to control acid mist emissions.
References for Section 7.15
1. Lead Acid Battery Manufacture - Background Information for Proposed
Standard:! , EPA 450/3-79-028a, U.S. Environmental Protection Agency,
Research Triangle Park, NC, November 1979.
7.15-4 EMISSION FACTORS 8/82
-------
Souice Test EPA-74-BAf-l, U.S. Envireminent-a 1 Protection Agency, Research
Triangle Park, i:n, March 1974.
source Tasting of Lead Acid Battery Manufacturing Plant - C1cbe-Union,
Inc., Canby, UR. EPA-76-8AT-4, U.S. Environmental Protection Agency,
Research Triangl? Park, NC, 1976.
R.C. Fulton and G.W. Zolna, Report of Efficiency, resting Performed
April 30. 1976, on American Air Filtfer Roto-Clone, Spotts, Stevens and
McCoy, Inc., Wyomissin^, PA, June!, 1976.
Source Testing at a Lead Acid Bat.tei.y /anufacturing Company - ESB, Canada,
Ltd., Hissiasauga, Ontario, EPA-76-3, U.S. Environmental Protection
Agency, Research Triangle Park, NC, 1976.
Emissions Study at a lead Acid Battery Manufacturing Coaip.iny - ESB, Inc.,
Buffalo, NY, EPA-76-BAT-2, U.S. Environmental Protection Agency,
Research Trianglfi Park, NC, ..976.
Test Xeport - Sulfuric^ Acid Eiiiissions from F.SB Battery Plant Forming Room.
Allen town, PA, EPA-77-BAT-5. U.S. Environmental Protection As?ei.;-y,
Research Triangle Park, NC, 1977.
b/32 Mctallurgii-.al Industry 7.15-5
-------
7.16 LEAD OXIDE AND PIGMENT
PRODUCTION
7.K-.1 General
Lead oxide is u*ed ir ihe manufacture o.f lead/acid slcrafie batteries (Section 7. 15) and at. a pigment in
pain!'. Black oxide, which is used exclusively in storage baltt-rifs. contain- 60 !•• 80 percent litharge (PbOl
the remiindei being finely o'ivided metallic lead.1 TKe major lead pigment i , red k-ad(Pb3O4', which is used
principal)) in ferrous metal protective paints. Other leafi pigments- include vvhitr lead and lead chrnmaU ••.
Most trad oxides and many lead pigments are derived from lead mor.oxidf (PbO) in the form oi litharge,
which i.^ produced by (l)panially oxidizing lead and Milling it into a powder, whkhis then completely oxi
dUed in arevcrberslury furnace; (?) oxidizing and stirring, pig lead in a ieverb»ratoi> furnar e or rotary kiln;
(3) running molten lead into a cupelling furnace: or ,4) atomizing molten ie:id in a flaint . The product must
be cooled quickly lo beluw 300'C (572T) to avoic" formatitm of ied lead.'
Black uxiOr i> usudlly produced (in the same furnace in vvhich (he litharge U made) by either the ball
mill or Barton process. Cyione* anH fabric fi!l'?rs collect the product. Red lead is- pn>duned by oxidizing
litharge- in a reverheralory furnace. Basic carDonale white leat! production is ba?fd on the reaction of
litharge with acetic acid or Lcr'ate ions. Whi*e leads other titan carbouttes ;-rc made either by chemical
or fuming processes. Chromate pigments ai- <, -ne rally manutactuied hv precipitation or calcination.
7.16.2 Emissions and Controls
Automatic shaker type fabric filters, of'en preceded by cyclone mechanical collectors or settling cham-
bers, are the almost universal choice far -ollecting lead oxides and pigment*. VI here fabric f :ri.-s are not
appropriate, scrubbers are u?ed, resulting in higher emission!-. The ball mil! and Barton processes of black
oxide manufacturing recover the lead pr«Jucl by these two mea.is. Collection of dust and fumes from the
pioduction of red lead i> likewise an economic necessity, >ini-e particular emissions, although small, are
about 90 percent lead. Data on emissions from the production of white lead pigments are not available, out
they have Neen estimated because cf health and safety regulations. The etuis-ions from dryer exha'ist
scr'iL'iers .ircoun' lor over 50 p«-rr<-nt of the total lead emitted in lead chromate production.
7/79 Melallurpical InduMr> 7.16-1
-------
Tabl* 7.16-1. LEAD OXIDE AND PIGMENT PRODUCTION EMISSION FACTORS*
EMISSION FACTOR FATING: B
Process
Lead oxide
production
Barton pot1'
Calcining
furnace
Pigment
production:
Red ipadb
White lead6
Chrome
pigment:
Partir.ulate
Ib'ton
produced
0.43-0.85
C
1.Cd
c
c
kg,'103>g
prod^ ced
C.21-0.43
c
O.bd
rf
C
Lead emission factor
Ib/ton
produced
0.44
14.0
0.9
0.55
0.13
kg/IO^ o
produce..1
0.22
7.0
0.5
0.28
0065
References
4/5,7
6
4.5
4,5
4.5
"Reference 4 pp. 4-283 ,^nd 4-i'B7
"Wsasumd ai baohouse oulle: Baqhouso is con. :o«sred p roc ass eqi.iprnenl
cDala not a.aiiable.
°0niy PbO ard oxygen jstv "\ red fead ppoduclioo. so parlictjlate smissions assumed lo be aboul 80°» .ead
Table 7.16-2. LEAD OXIDE Al'O PtCMENT PRODUCTION CONTROL EFFICIENCIES
Process
Lead oxide and
pigment producticn
3
e 4
Control
v.dcnanical shaki-r fabric
filter (preceded by dry
cyclone or settling chamber)
^cruboer
Percent
reduction
99a
70-95b
7.16-2
EMISSION FACTORS
7/79
-------
Rrfrrpnri •» for Section 7.16
1. K. J. Kitrhif Lead Oxide*. Indfj) mlent Battery Manufariurt- rs Association Inf., Largo. J L. 1974.
2. U K. ^avis. Emiision'i Stml\ at Industrial tourer* of Lfiitl Air I'ullutnnu, 1'J'O, EPA C.mtn.i ' s(.i.
6H-02-0271, ',V. K. Davis and \>sn'iati-s. Lfdw.iod. KS. April \915.
3. karkgrnund Information in Sni>/xi-t i-()2-2()85. PEDro-EnviioiimentalSpi-cialists. Inr., Cincinnati. OH.
Janu.. .\ 1976.
4. Cuntrni Tn-hniqutu for Lful Ai> Emissions, EPA-450/2-77-012. t'.S. EriMromifntal
-y. R«fs«-arfh Ttianglr 1'urk. N(i. LVcembei 1977.
S. R. P. Belz. tt ul.. Economic"; of Lriiil Rtmwal in Se/rcteii Industries, EPA Contract No. 0
Baltellf Colurnbus Laborutorie.-;. Columbus. OH. Drreinber 1972.
6. Emission Test No. 71-PB-O-]. <)l'tin> »!' Air Quulit> Planning jiui Standards. U.S. Fn\in>Mnn-ntal
Protection Agency, Kesvarch Triangle Park. -N'. , August 15J73.
>IetalJur«irH) Iridiistr^ 7.16-3
-------
7.17 MISCELLANEOUS LEAD PRODUCTS
7.17.1 Tvpe Metal Production
7. 171.1 l.>-neral - Lr as segment • •( the printing industry. is i .isl
1'i.ni .1 mull n It-ad alloi ami remeltrd after use. Linotype and mo.iolype pr ><(•*.>»•> product- « mold. whil>-
pe prot es-» piodurts d plate fur prmtirg. All U pr metal is an tilloy c on«isting of 60 !•> 85 pm-fiit
recovered lead, wilh ai tummy, iin and .' -.null ,in>m, nl of virgin metal.
7 17.1.2 Kmissums and Controls - The melting pot U the major suui'-e of emissions. containing lucro-
iMiliu'i,- a.- vtcll as lead parliculales. Pouring the molten metal i'1 •< th»- molds Involves Mjrfnre nxidalinn of
the nulal. pos»it>lv pruducing oxidi;t-d lumes. while the trimming and flnisliin|i <>p<.-rali. it is rstiinjled that 35 percent of the tutul emitted paniculate is lead '
Apprn litiiutely half of the cm rent Irad type uperationsctr I ml lead emissions, by about 80 pfN-ent. The
utluvupt'iiluins are uncunlrolled.2 Hie must fri/quenllv r-dntrolled sourr c* are the ivain rneltinjt pots ;.-:nd
dr«is>in(t ar-'a*. Linotype equiptnriit do':* not rrquirr I'linlids when operated prope ly. Devic . s in run .Jnl
ii!-e i>u mom type and stereotype lines include niioc-lones. wel #'Tuhbers, fabric illte's, and eU'ctr
prei'ipilaiors. all which can be u*rd i,. varx/ui Cfmlunalinn*.
7.17.2 Can Soldering
7.17.2.1 Process Description - Side S'.'ams of CMOS' are -oldereij on a machine consisting of a
o'jted roll uperutiiijnn a balh<>f ninltrn *n|der. typicaiiv ri.ntainin^ ^8 prii-ent lead Alter s'-iderinit '-vi e--
IK wppd aua\ by a rotating cloth ! uffir. which erf j!es «omr dust (Table 7.17-il.3
7. 17.2.^ Kiniisinns anu Controls - Hniifi». e\hu^J^! duot- jnd inr< hani< al cy lunrs (Table 7. 17-2i ."
the lar^e Flakes generated at the wiping s'alion. but some dust escapes in thr form of particles 20mi( ion« or
smaller, with a lead content of 3 !<• 38 percent, Maintuiniv,^ a (food flux cover i? thr most elfei'tivi- meuri1-
of i i»nlroHiiig Irad emissions from the -older hatch !.<»* ••net ji\ wet ( ollertors .ir f;ihrir filters c'an aUo con-
trol Irad emissions from c;ni soldering.
7.17.H Cable Coverinfc
i". 1 7.3. ! Ptucess Drscripti' n -- Ahoiit SH) percent oft he lead rah IP covering produced in the Li He d State*
i~ It a(i cur. (I ja* ketrd i able.- and 10 percent is on lead sheathed c ables. In preparation of the former type.
•in unjllosed lead cov;-r applied in (he vulcanizing treatment during tbi- munufuclure of rubber in-ulatrd
uncontrollpd.4 Average particle >ize is approximately 5 microns, with a lead contem of
dbout 70 to 80 percent. '••'
Calr" roiering procrsses do not usufeUy include paniculate ne col]rctur> can : educe lead t- missions I Table 7. 17-2 1. Lowering and
I'linlrnlling th' me.t temperature. enc'li>«inp thf- melting unit and usinp fluxes to provide a ru\er on the melt
can also minimi/' en'issjons.
7/79 Metallurgical IndiiHr^ 7.17-1
-------
Table 7.17-1 EMISSION FACTORS FOR MISCELLANEOUS SOURCES8
EMISSION FACTOR RATING: C
Process
Type metfl
production
Can soldering
Cable covering
Metallic lead
products
Ammunition
Bearing metals
Other sourcos
of lead
Participate emission (actor
Metric
0.4 kg/103 kg
Pb proc"
0.8 x 10'
baseboxes
prod*
0.3 kg/103 kg
Pb proc"
a
e
a
English
0.7 Ib/ton Pb
procb
0.9 ton/1 0s
base boxes
prodc
0.6 !b/ton Pb
procd
e
e
e
Lead emission factor
Metric
0.13 kg/103
kg Pb pror
160 kg/106
baseboxes
prod'
0.25 kg/103
kg Pb proc
^0.6 kg/10e
kg Pb proc
negligible
0.8 kg/103 kg
Pb proc
English
0 25 Ib/ton
Pb proc
0.18 ion/106
baseboxes
nrod
05 Ib/ton Pb
proc
1.0lb/103ton
Pb proc
negligible
1.5 Ib/ton Pb
proc
References
2,7
7
3.5,7
3.7
3,7
3.7
'Proc - processed; prod - profl-cefl.
"Calculated on tht; bas s of 35% ol '.he tola! (Reference 1)
:He»erence 7, pp 4-297 and 4-2S-8
1Reterence 7 p 4-301
'Data not available
'Basebox - iO 23 m* (217 6 It*) standard tin plcle she»t area.
Table 7.17-2. CAN SOLDERING AND CABLE COVERING
CONTROL EFFICIENCIES
rocess
Can .-.oldering
Cabl J ccvering
Control
Mechanical cyclone 75
Fabric filter 99.9
Rotoclone w«t collector
Dry cyclone collector 45
Percent
reduction
*Rel» -ence 7
7.17-2
EMISSION FACTORS
r/79
-------
7.17.1 MrtHllir l.vml Products
7.17.1.1 General lead i* roti-urmd and emitted in the mairul-ieliire nl <>!miiuiii!i<>n. i/tani^ metals
.itid other lead jinuiurt-. Lead u>ed in the manufacture of ariniun>tii> . is incited and alloyed bHore it is
• ar-t. sheared, i \ti ndri), s\> ajied m media m ( ,il!\ worked. Si i nit* lead is aUo r c.i< ted lo i-.i in lead a/.idr. A
det»naliii\ • jlloviti|£ il wiiln'mnn-r. liron/-1. antaii"iu and li'!.
Olhc ; Irad (iimlucl- include IIM 'ir- inci.il ;a (ilatin^r ali<.\ '. weinlil.- J.M! liall.i-i^. i aulkinj! i-'ad. [ilunihii.n
-,i|iplit'-. TIM fiiij: material.-. cd>iiri|2 :tiel«l Iml. eol|j|)si!ilc ii.etal t:il)e» and ^h«-t-i .ead. Lead i» al-n u~»-d |.>i
>. aniiealiiit and platii.p II is usual] n-.cltpd and fast prinr to rnei h.inii al lormiti^;
7 17.4.2 Fmi!-;]iin> und CuiiCiil.- l.i'llei.r im air p..|luli"n cuiilrol ei|uipinenl i> cunt ml> i.-cdln imuiii-
Uciuier.- >.A niftaliii iejit product'-.'' KiiiisMtins Hum bearing nianulac'ture aie negli^iliU-. rven willun.t
fontruls.J
References for Section 7.1 7
1. V J. Kulujia. Inspection Manual Jui the Enforcement uj .\eu Source Pfrjornnir^.t Stuni/tints:
Portland Cvn;.-nl /'/uHls, tPA Contract No. 68-02-1355, PEl>Cu-tn\itniimeiital Sj-txiaJisN. Inc..
Cincinnati. OH. January 1Y7.S
2. \inn>$phfric Emitsiuns fntm I. surf T\/if settinp Optrutio; Srrceniie >Sfti. Kf'A (imuraot \o. 6H-i)2-
2(185. FKDCo-tn\injnnierta] Specinlists. Inc.. Cincinnati. OH. January 197 j.
\\ K D.ivi.-. Kmi.\i>!!>.!A ^rnf In'luitmtl Eunices i-f Lrud Air
6«-u2-0271. W. t. Uavi.- Af>,,, iatr-. l.<>u\voi,d. KS. April J"7.-i.
i R. P. Br'/. ft ill.. Kt-ulniinii-s ul Lrrlii R^WoKii in SelfCleil tntln*l IK'<. El' \ f'./nii J< t \> <)H-!iJ-i!61 1,
Rallell' (iolumhus l.-umratorir*. ( .ohunlius. OH. \utiiisl 197^.
,i. E. P Slu-d. Emissions from CiMr(.<>\f. iif- FiiciliiY. EPA ("ontraci No. 68-0;Ml22K. \hdwc-l He-
?',-atcli Instil jte. Kansas Cu\. \!(). June lVi'3.
f>. Ifinrrul hnln.\f\ Snrte\f Ltd't Intlustn ',p \1n\ ]97ti. Bureau of Minos. I .S. Department «'. th<>
Intcnur Tlashinnton. DC, •\usu-! 1976.
1 (..onlrtii Ti-1'hnn/itfs fur l.fail Air Eiinsstufis. I,PA-450'2-77-yl2. L.>. Err. irnnnienial Proteclu-n
A^eiicv. RfM'wrch Irianiih.' Park. N(J. Ileeernlier 1977.
Meldlluryical Inrtii'.trv 7.17-S
-------
7.18 LEADBEARIMG ORE CRUSHING
AND GRINDING
7.18.1 Proress Description
Lead and zinc HITS ai? n<>riiiull> deep iiiinni. \«. herea* 'upper uri'» jr«' open pit mined Lead. /me Hii.i
(upper are usually found Injjethei 1111 *arsisi(i percentage.') in conibindtion willi sullur \\j:eii.
In underground mines, the <>re i~ dir-inlejirated \>\ pf>mi:--ise drilling ni.'f hin<-*. run thmn^li a pri:iuu\
(rusher, and ihen conveyed tn the "iirfacf. in open pit mines, ore and ^an^ur are lnosened .inti pulven/rd
by f uplusives, >-o'njp«.id up by intr-'lidiiic-il fquipnif lit. and iiiin*|M>rlrd l» llu- 1 1»'«
Sundaid cru'-rier>.. screen*, and . -.'H MM] ball mili* classify und reduce the ore ti> p«.>wdei> in the fK< m j25
nitbli ran^'-. The finely divided particle* ar»" separated from the gangue and are coin culrated in j liquid
medium by gravity and/or selective flotation, t he ri cleaned, thioltennl and filtered. The concentrate i* tliied
prior to ''liipinent ID the smelter.
7.18.2 Emissions and C^onlrols
Lead emissions ure lia>ically lu^itni-. I'j'ised b\ ilrillin^. iilusiini;. loading. coinc\inp,
unloading, crushing and grinding. The primary means of control are pood mining techniques jnd ct.uip-
ment maintenance. These practice? include enclosing the uuck loading operation, welling or co\rriii|i
Irui'k lui
-------
Table 7.18-1. EMISSION FACTORS FOR ORE CRUSHING AND
GRINDING
EMISSION FACTOR RATING: D
Type of
0'e
Pb<=
Zn
Cu
Pb-Zn
Cu-Pb
Cu-Zn
Paniculate
emission factor3
ib/ton
processed
6.0
6.0
6.4
6.0
6*
6.4
Cu-Pb-Zn I 1 .4
kg/101 kg
processed
3.0
3.0
3.2
30
3.2
32
32
Leac
emission factor^
Ib/ton
processed
03
0012
0.012
0.12
0.12
0.012
O.U
kg/101 kg
processed
0.15
0.006
u.006
'J.06
0.06
0.006
006
'Reference 1 pp 4-39
^References 1-5
cRe*er to Section : j
References for Section 7.18
1. Lanlr'jl Technique? 'or Ltud .\i> £mi.ssiun.i . lil' \-4.iOi2-TT-01i. I . S Kmir*n:iiM* nlal Hmtoi timi
>carrh Tna,,;:!e Park. \C. Drrcrabrr 1977.
2. ^ . E Davi?.£r. .i>sium ^tmli of lmttntri. tl'A Cuntra< I N".> 68-02-(12Tl.
U. E. Davir and .Wudaie*. l.eawm.d. K>. \pril 1973.
3. Eniironmtnta! \Mtiiment of the Dvmeslir Pr'.ir\ar\ (?y;i/jf, . Lmit, aid Zinc lnJuttr\. EP \ (!i>r.liiict \n. A8-02-
1321. PEDCO-Envirdnrnfnlal S-pecialisls. Inc.. Ciiu-inrati. OH. September 1976
1. C iiiiniuniraiiuii uiih Mr. J. Paui'-k K« an. Burruu uf Minr?. I . ^. Drpanntrni uf thr l.itei i. Vk a^htt•gll•n. Iw"!.
9 19"''.
5. Fi (j. \\i\-..i and J. C. Jenncit. "llu- Nf^« Lead Bell in tin- F'«re»ifi; U?jrk* t'f Mi-^ii.n". Ent iroaiientnl
\irr.r, „<,,! Tfrhnnl«f\ 'J< U'.< 128-1 u
r.ie-2
EMISSION FACTORS
T/79
-------
8. MINERAL PRODUCTS INDUSTRY
1 his section in volves the processing and pioduction of various mineral. Mineral processing i« characterized
by paniculate emission^ in the form of dust. Frequently, as in the case of crushing and sere' 4, this dust is
identical to tru- material being handled. Emission* also occur through handling and storing the 'led product
because ihi- material is cfien dry and fine. Paniculate emissions from some uf the processes s>> quarrying,
yard storc.gt:. and dust from transport art difficult to control. Most of the emission* from the mn .itact«irin(t pro-
cesses discussed in this section, however, can be reduced by conventional pai ticulate control equipineal such as
cyclones, scrubbers, and fabric filters. Because of ihr wide var^-ly in processing equipment ar.d final produi.!.
eirisaions cover a widr range; however, average Tnissioi, lactors have been presented for general use.
4/81 Mineral Products Industry 8.0-1
-------
8.1 ASPHM/TIC CONCRETE PLANTS
8. L.I General
Asphaltic concrete (asphalttc hot ,plx) Is a paving material
which consists of d combination of graded aggregate that Is dried,
heated and evenly coated with nor asphalt cement.
Asphalt hot mix is produced by mixing not, dry aggregate with
hot Liquid asphalt cement, in hatch n«- continuous processes. Since
different applications require different aggregate size distribu-
tions, the aggregate is segregated by size and is proportioned into
tha rni,\ as required. In 1975, about 90 percent of total U.S.
production was conventional hatch process, and most of the remainder
was continuous batch. The dryer drum process, another method of
hoi mix asphalt production, in which wet aggregate Is dried and
mixed with hot liquid asphalt cement simultaneously in a dryer,
comprised less thap. 3 percent of the total, but most new construc-
tion favors this design. Plants may be either permanent ur portable.
Conventional Plants - Conventional plants produce finished asohaltic
concrete through either batch (Figure 8.1-1) or continuous
(Figure 8.1-2) aggregate mixing operations. Raw aggregate Is
normally stockpiled near the plant, at a location where the mois'nre
content will st-ihllize to between 3 and 5 percent by weight.
A.£ pLucesiJing for either tyno of operation begins, ».hu ftg
is hauled fnm t.i.ti st ">raga piles and mixer. The hot mix is
then dropped into a truck and hauled to the job -jits.
In a continuous pl^.nt, the classif red jggregate drops into a
set of small bins which collect and met«r the classified aggregate
to the mixer. "rum tlu' hot bins, the aggregate is metured through
4/81 '.-linera.. Products Industry 8.1-1
-------
CD
M*
fe
EXHA15TTO A
ATMOSPHERE *
M
-
35
CA
H
SO
Cf-
PRIMARY DUST
COLLECTOR
COARSE
AGGREGATE
STORAGE
PILE
FEEDERS
CONVEYOR
81-1 Batch hot mix asphalt plant. "P" denotes paiticulate emission points.1
-------
2
5'
o
a,
c
9
B.
e
SECONDARY
COLLECTION
EXHAUST TO
ATMOSPHERE
s:::.-.-;.;ci\ COLLECTOR
COAKSE FINE
AGGREGATE AGGREGATE
DRAFT FAN (LOCATION
DEPENDENT UPON
TYPE OF SECONDARY)
FEEDERS
CONVEYOR _J
ADJUJfABI.E
DAD
STORAGE
TANK
(OPTION.1L)
ELEVATORS-^
TRUCK
8. i 2. Continuous hot-mix asphalt plant. "P1 denotes particulate emission points.1
-------
a set of feeder conveyors to another bucket elevator and Into the
mixer. Asphalt is mattered through the inlet end of the mixer, and
retention time is controlled by an adjustable dam at the end of the
mixer. The mix flows out of the mixer into a hopper from which
trucks are loaded.
Dryer Druii Plants - The dryer drum process- simplifies the conven-
tional process by using proportioning feed controls in place of hot
aggregate storage bins, vibrating screens and the mixer.
Figure 8.1-3 is a diagram of the dryer drum process. Both
aggregate and asphalt are introduced near the flame end of the
revolving drum. A variable flow aspha1.t pump is linked electron-
ically to the aggregate belt scales to control mix specifications.
Dryer drum plants generally cut parallel flow design for hot
burner gases and aggregate flow. Parallel flow has the advantage
of giving the mixture a longei time to coat and to co..iect dust in
the mix, thereby reducing particulate emissions to the atmosphere.
The amount of particulates generated within the dryer in this
process is lower than that generated within conventional dryers,
but because asphalt is heated to high temperatures for a long
period of time, organic emissions ari greater.
The mix is discharged from the revolving dryer drum into surge
bins or storage silos.
22
Recycle Process for Drum Mix - Asphalt injected directly into the
dryer in the drum mix process is uniquely suited for the new, fast
developing technology of recycling asphalt pavement. Many drum mix
plants are now sold with a "recycle kit", which allows the plant to
be converted to process blends of virgin and recycled material.
In a. recycling process, salvaged asphalt pavement (or base
material) that has been crushed and screened is introduced into the
dryer drum ac a point scraewhere downstream of the virgin e^jgregate
inlet. The amount of recycled pavamunt thaf. can be successfully
processed has not y^t been determined, bat eventually, as t'le tech-
nology is developed, the blends may approach 1UO percent rcrycled
material. Current blends range fron about ?0 percent to a maximum
of 50 percent recycled material,
The advantages cf the recycling process are that blended
recycled material and virgin aggregate are generally less expensive
than 100 percent virgin aggre^te, liquid asphalt requirements are
less due to residual asphalt in the recycled material, and the
recycled material requires less drying chan the virgin aggregate.
The chief problem with recycling is opacity standards, because of
emissions of blue smoke (an aerosol of submicron organic droplets
volatilized from the asphalt and subsequently condensed before
exiting the stack). However, current recycle plant designs have
8.L-'+ EMISSFON FACTORS 4/Bi
-------
n
1-1
Oi
O
u.
r,
g.
c
AGGREGATE STORACE BINS
VARIABLE SPEED
CONVEY 3P.
ASPHAll
STORAGE
TANK
C7f\ ASPHALT
( f J PUMf
BURNER AND
TURRO^bMPRESSOR
NOT MIX
CONVEYJH
HEATED
STORAGE
SILO
FINISHED
PRODUCT TO
JflUCKS.
8.1-3. Shearer type dryer-drum hot asphalt plant.
oo
i
Ul
-------
reduced blue smoke emissions greatly by preventing direct contact
of flame and liquid asphalt PS 1t Is Injected.
8.1.Z Emissions and Controls
Emission points at batch, continuous and drum dryer hoi mix
asphalt plants numbered below refer to Figures 8.1-1, 2 and 3,
respectively.
Emissions from the various sources in an asphaltLc concrete
plant are ver.ted either through the dryer vent or the scavenger
vent. The dryer vent stream goes to the primary collector. The
outputs of the primary collector and tlie scavenger vent go en the
secondary co/ lector, then to the stack. (1) for release to the atmos-
phere. The scavenger vent carries releases from the hot aggregate
elevator (5), vibrating screens (5), hot aggregate storage bins
(5), weigh hopper and mixer (2). The dryer vent carries emissions
only from the dryer. In the dryer drum process, the screens, weigh
hopper and mixer ar«; not in a separate tower. Dryer emissions in
conventional plants contain mineral fines and fuel combustion
products, and tha mixer assembly (2) 'ilso emits materials from the
hot asphalt. In dryer drum plants, both types of emissions ariss
in the drum.
Emissions from drum mix recycled asphalt plants are similar
to omissions from regular drum mix plants, except for greater vola-
tilfe organics due to direct flame volatillzacion o£ petroleum deriva-
tives: contained in used asphalt. Control of liquid organic emissions
in the drum mix recycle process is by (1) introduction of recycJed
material at the center of the drum or faither toward the discharge
end, coupled with a flight design tha* causes a dense curtain of
aggregate between the flame and the residual asphalt, (2) protection
of the material from the flame by a heat shiald, or (3) insulation
of the recycled tnaterlal from the combustion zone entirely by a
tirum-within-a-drum arrangement in which virgin naAerial is dried
and coated in thr. inner drum, recycled material is indirectly heated
in the annular space surrounding the inner drum, and the. materials
are mixed at discharge of thi: inner drum.2
Potential fugitive pacticulate emission sources from asphaltlc
concrete TliinLs include unloading of aggregate to stcrage bins (5),
conveying aggregate by elevators (5), and aggregate screening
operations (5). Another source of partlculate emissions Is the
mixer (2), which, although it is panerally vented Into the secondary
collector. Is open to the atmosphere when a batch is loaded onto a
truck. Thi-s Is an intermittent operation, *nd ambient condiLiuns
(wind, etc.) are quite; variable, so these emissions are beat regarded
as fugitive. The open iruck. (U\ C.AO also -^e a -source of fugitive
VOC emissions, as can the asphalt storage tanks (3), wnich may also
en.lt small amounts cf polycyclics.
3.1-6 EMISSION FACTORS 4/81
-------
Thus, fugitive particulate emissions from hot m'x: asphalt plants are
mostly dust from aggregate storage, handling and transfer. Stoue dust nay
range from 0.1 to more than 300 micrometers in diameter. On the average, S
percent of cold aggregate feed Is less than 74 micrometers (minus 200 mesh).
Dust that may escape before reaching priraary dust collection generally Is 50
to 70 percent less than 74 micrometers. Materials emitted are given In
Tables 8.1-L and 8.1-4.
Emission factors for various materials emitted from the stack are given
In Table 8.1-1. With the exception of aldehydes, the materials listed la this
Table are also emitted from the mixer, buc mixer concertratloas ara 5 to LOO
fold smaller Lhan stack concentrations, lasting only during the d.'acharga of
the mixer.
TABLE 6.1-1.
EMISSION FACTORS FOR SELECTED MATERIALS FROM AN
AS?HAI.TIC CONCRETE PLANT STACK*
Material emitted*1
Partlculated
Sultur oxides (as S02) '*
Nitrogen oxides (ad IM^;
Volatile organic compounds'
Car'uon monoxide^
Polycycllc organic matter^
Aldehydes^
r'ormaldehyde
2-Methylpropanal
Usol utyraldehydc )
1-Butanal
(n-butyraldehyde)
3-Methylbutanal
(isovaleraldenyde)
Emission factorc
g/Mg
137
146S
18
14
19
0.013
10
0.077
0,63
1.2
1
8.3
Ib/ton
.274
.2928
.036
028
.018
.000026
.020
.ooo:.5
.0013
.O0'i4
.016
Emission
Factor
Rating
B
C
0
D
D
D
D
D
D
D
D
aReff»rence 16.
^articulates, carbon monoxide, polycy;lics, trace rcctals and hydrogen
srlfide were observed In the mixer emissions at concentrations that were
small relative to stack concentrations.
cExpressed as g/Mg and Ib/ton of asphaltic concrete producti.
^Mear of 400 plant survey source test results.
"Reference 21. S ™ % sulfur in tuel. S02 may be attenuated >50% by
adsorption on alkaline aggregate.
fBased on limited test data from the single dsphaltic concrete plant
described In Table 8.1-2.
4/81
Minsral Products Industry
8.1-7
-------
Reference 16 reports mixer concentrations of SOX, NOX, VOC and
ozone as less than certain values, so they may not be present at
all, while particuiates, carbon loonnxide, polycyclics, trace metals
and hydrogen sulflde were observed at concentrations that were small
relative to *tack amounts. Emioslonn from the mixer are thus best
treated as fugitive.
The materials listed in Teble 3.1-1 are discussed below.
Factor ratings are listed for each material in the table. All emis-
sion factors are for controller operation, bused either on average
industry practice shown by survey or on a .tual results of testing
in a selected typical plant. 'Che characteristics of this represen-
tative plant are given In Tablu 8.1-2.
TABLE 8.1-2. CHARACTERISTICS OF AN ASPHALTIC
CONCRETE PUNT SELECTED FOR SAMPLING
Parameter
Plant Sampled
Plant type
Production rate,
Mg/hr (ton/hr)
Mixer capacity,
Mg (tons^
Primary collector
Secondary collector
Fuel
Release agent.
Stack height, ra (ft/
Conventional permanent
batch plant
160.3 1 16X
(177 ± 16%)
3.6 (4.0)
Cyclone
Wet scrubber (venturi)
Oil
Fuel oil
15.85 (52)
Reference 16, Table 16.
The industrial survey showed that over 66 percent of operating
hot mix asphalt plants use fuel oil for combustion. Possible sulfur
oxide, emissions from the stack ware calculated assuming that all
sulfur in the fuel oil is oxidized to SOX. The amount of sulfur
oxides actually released through the stack may be attenuated by
water scrubbers or even by the aggregate Itself, if limestone is
being dried. No. 2 fuel oil has an average sulfur content of
0.22 percent.
Emission factors for nitrogen oxides, nonn:ethane volatile
organica, carbon monoxide, polycyclic organic material and aldehydes
8.1-8
EMISSION FACTORS
4/81
-------
were determined by sampling stack gas at the representative asphalt
hot mix plant .
The choice, of applicable control equipment ranges from dry
mechanical collectors to scrubbers and fabric collectors. Attempts
to apply electrostatic precipitators have met with little success.
Practically all plants use primary dust co1 lection equipment such
as large diameter cyclones, skimmers or bt.ttling chambers.
chambers are often used as classifiers to retuir. collected
to the hoc aggregate elevator combine it with the drys.i'
load. The primary collector effluent is ducted to f! 'ie.conii.Hi/-
cullectlon device because of high emission le^cl^ it venlcl *u '.;•*•
atmosphere.
TABLE 8.1-3. PA.RTICUUTR Ll'lSSlON FACTO P.:, FOR
CONVENTIONAL HOT MIX
EMISSION FACTOR RATING;
Emission. Vi
Type of Control
Uncontrolled*"1
Precleaner^
High efficiency cyclone
Spray tower
Baffle spray tower
Multiple centrifugal scrui-her
Orifice scrubber
Venturi scrubi.s»rf
n
Baghouae
kg/Mg :
22 = 5 \
7,5
0.8b
0.15
0.03:
( (
0.0-
0.02
C..C!
V
"• <>?.
^References 1., 7, 5-10 arc1 is-16.
Expressed ii terras of ^ir.is.-io.^ per \i?.>... velgr.t ot' ai:.>hai.rx>
concrete produced.
"Almost j.11 7>!ant3 have at ioast -i . "(?a:\?.r fol 1'»vi.n,j -^ht.
•rotary dryer.
Reference 16. These factors differ Zvou :h>.so jji.-cn \.t:
Table 8.1-1 becausa tliey are for urif.onL.'oi.1 t-i P^.\ sr x j-vs a:."1-
are ft-om an earlier surviy.
fcRefererce 15. Average emission from a p-'c.;.,- ?> t'^nlgop..-,,
in^tallbd, opernttd and mal ntjineJ pcrubbei h^s-'J u'i a
-study to develop New Source Psrf o-.nt.uce Staiiii.;r''s.
References 14 ^nd 15.
Reiarances 14 ana 15. Emissions f^otn a properly uf.^Lj. t,-'>
installed, opp.rated and Tiaii,twined haghoust, bosod ou a s*:>.'v
to Envelop New Source ?erformt»->c.t: Standards.
4/81 Mine.al .'roducts Tadastry 3.1-S
-------
i^ ulite emission f Actor«=. -for convent lona'i'axjp^aj.jtic concrete
lant-* «re presented <". T<»LV'« 8,1-3. Particle si/e distribution- •-.._
^nfortnatioa b?.i not been ir.c1«v1ed, becausr-. rhe nartlcle size diatti-
u'.'.s:-;. waTica-.-lth th* aggregate btir.g vseii, th-3 mix being made And
. v- ,:"[>*• ot pli^t vj-crafinn. Potential fugitive nartlcuiait: czis-
ion tAcrTrs*".'"-" Ci-.i. .-£_•:** on*! ason^;tic concrete plants are shovn
i^.iil--te eul:;-?'on factors, ior Hr-.or diura giants are presented
1 -1 !»'•"'« o,i--i. (~il;er---' -J-. 41, j^*-i f^r other pollutar.ts reitss^d
t'coi t^- ,':','-- oru-i 'r\rit. mix oiocess.) Faixi;.1 =^_stze distribution
--- 4; -r\ v 'c^.^jT^'ided. because ii v.-.ri?-? with the^aggre-j^r-0. ..iised,
: . - ••-<.*>. • -_i .— ',->; «t_ plane upti a. 1.-.- , ETsis«?lon factors " iuc
...-»,•,-, ,1.,,^.^ •-, ^. ui-.c^r.'.iC-l^ ' .."•«"< i.rti, .ary ty 1 Tdctof c
-------
TABLE H.l-fc. •.vTENTtAL 'JNCONTROLLED FUGITIVZ
PARTICULATE EMISSION FACTORS FUR CONVENTIONAL
ASPHALT1L CONCRETE PLANTS
EMISSION FACTOR RATING: E
Particulatesa
Type of Operation kg/MgIb/ton
Unloading co..r:-e an:1, fine
aggregate to storage binsb G.05 0.10
Cold and dnc.d Und hot)
a ggr *£«.£;. t:evatorb 0.10 0.20
Screening hot aggregate^ 0.013 0.026
per unit weight of aggregate.
Reference 18. Aa-i--^ed equal to similar sources.
Reference 19. Asssumed eq^l to jlmllar crushed
granite processes.
TABLE 8.1-5. PARTICIPATE EMISSION FACTORS
FOR DRYER DRUM HOT MIX ASPHALT PLANTS
EMISSION FACTOR RATING: fl
Type of Control
Uncontrolled
Cyclone or raulticyclone
Low energy w«>t scrubber
Venturi scrubber
Emission
kg/Mg
2.45
0.34
0.04
0.02
Factor
Ib/ton
4.f>
0.67
0.07
0.04
.Reference 11.
Expressed in terns oE emissions per unit weight of
asphalt concrete produced. These factors differ
froa those for conventional asphaltic concrete
plants because the aggregate contacts, and ts coated
with, asphalt early in the dryer dr itn process.
'ither stack spiayo where water dropleta are
injected into th? exit stach, or a dynamic scrubber
that iacorporates a wtt fan.
4/81 Mineral Products Industry 8.1-11
-------
9. J.A. Danielson, Unpublished test data from asphalt batching
plants, Los Angeles County Air Pollution Control District,
Presented at Air Pollution Control Institute, University of
Southern California, Los Angeles, CA, November 1966.
10. M.E. Fogel et al., Comprehensive Economic Study of Aii Pollution
Control Costs lor Selected Industries and Selected Regions,,
R-OU-455, U.S. Environment*! Protection Agency, Research
Triangle Park. N'C, February 1970.
11. Preliminary Evaluation of Air Pollution Aspects of the Drum
Mix Process, SPA-340/1-77-00^, U.S. Environmental Protection
Agenf.y, Research Triangle Park, N7C, March 1976.
12, H.W. j^aty and B.M. Bunnell, "The Manufacture of Asphalt
Concrete Mixtures in '.he Dryec Diuni", Frtsented at the Annual
Meeting of the Canadian Technical Asphalt Association, Quebec
City, Quebec, November l?-21, 1973.
13. J.S. Kinsey, An Evaluation of Control Systems and Mass Emission
Ratee from Dryer DjcumHot Asphni L' Plants, Colorado Air Pollutioi
Control Division, Denver, CO, December 1976.
!'•. Background Information for Proposed New Source Performance
"Standards. APTD-1352A~and B, U.S. Environmental Protection
Agency, Research Triangle Park, NC, June 1973,
15. Background Information toe ?'w Source Performance Standards,
3PA ^50/2-74-003, U.S. Environmental Protection Agency, Research
Triangle Park, NC, ^ebruary 1974.
16. Z.S. Kahn and T.W. Hu^he.s, Source Assessicjeiit; Asnhrlt Paving
HotMix, EPA Contract No. 68-02-1874 Monsanto Research
Corporation, Paytor., OH, July 1977.
17. V.P. Puzin^uskas and L,W. Corbett, Report on Zmissit ns from
Asphalt Hot Mixes, RR-75-1A, The Asphalt Institute, College
"?ark, MD, May i.97 J.
18. Evaluation of >ug_i_t_iva DiiBt From Mining, KPA Contract
No. 68-02-132.L, redco Environmental Specialist;-', Inc., Cincinnati,
OH, June 1976.
19. J.A. Peters and P.K. Chaltkode, "Assessment, of Open Sources",
Presented at the Third National Conference on Energy and the
Environment, Col"e3e Corner, OH, October 1, 1975.
20. Illustration of._|)_ry_er Drum Hut Mix Asphalt Plant, Pacific
Environmental Services, Inc., Santa Monica, CA, 1978.
8.1-12 EMISSION FACTORS 4/81
-------
21. Herman H. Forstaa, "Applications of Fabric Filters to Asphalt
Plants", Presented *t the 7lst Annual Meeting of the Air Pol-
A-iti* n Cciit-
-------
8.2 ASPHALT ROOFING
8.2.1 General1
The asphalt roofing industry manufactures asphalt saturated ftlt
rolls, shingles, roll roofing with miner?!, granules on the surface, and
smooth roll ;-oofii\g that may contain a small amount of mineral dust or
mica on the surface. Most of chese products are used in roof construc-
tioi, with small quantities used in walls and other building applications.
8.2.? Process Description
The manufacturing of jspholt felt, roofing, and shingles involves
the saturating and coating oj. felt with heated asphalt (aaturant asphalt
and/or coating asphalt) by means of dipping and/or spraying. '*ne process
ran be divided into (1) asphalt storage, (2) asphalt blowing, (3) felt
saturation, (4) coating anu (5) minc'ral surfacing. Glass fiber is
su.netimes used in place of the paper felt, in which case the asphalt
saturation step is bypassed.
Preparation of the asphalt is an integral part of the pxodu;^iou of
asphalt roofing. This preparation, called "blowing" involves the
oxidation of asphalt flux by bubbling air cnrough liquid asphalt flux at
260°C (500°F) for 1 to 4.5 hours, depending on the desired characteristics
of the asphalt, such as softening point a.id penetration rate.2 A typical
plant will blow froir. four to six batches p-?r 16 hour day, and the roofing
line will operate for 16 hours per 'day and 5 days per week. Blowing may
be done either in vertical tanki or in horizontal chambers. Inorganic
salts such as ferric chloride (FeC^) may hr used as catalysts to achieve
desired properties and to increase the rat? of reaction in the blowing
still, thus decreasing the time required for each blow.3 Air bio..'ing of
asphalt may be conducted at oil refineries, asphalt processing plants,
and asphalt roofing plants. Figuie 8.2-1 illustrates an asphalt blowing
operation.
Figure 8.2-2 shows a typical line for the manufacture of
asphalt-satura'.ed felt, which consists of c paper feed roll, a dry looper
section, a saturator spray section (if uced), a saturator dipping section,
steam-heated drying-ill drums, a wet looj.r:r, waUr cooled rollers, a
finish floating looper, and a roll winder.
Organic telt n.dy weigh from 25 to 55 pounds per 480 square feet (a
common unit in Llie paper industry), depending upon the intended product.
The "ielt is unrolled from the unwind stand into the dry looper, which
iu^:r.tains a constant tension on the material. !>om the dry looper, the
felt rniiy pass into the spray section of the saturator (not lised in all
plants), whs-re aspiiaii j-L-2^i° tr, 2500L (*2i° to 480°F) is sprayed onto
.>ne side, of uhe i"?]t through --t.-'eral noziiltfs. Ln_ the salurator dip
section, the s;. tar a ;.;•••! telt i.b drawr. over a series of roller;, with the
bottom rollers submerged in hot a::ohait at 2CS° to 250°C (400° to 480°F).
Induifvv ' 8.2-1
-------
KNOCKOUT BO
OF CYCLOfiE
WATLK VAPOR, Gil.
AND PARTICIPATE
^ y
K
WATER VAPOR Tn
PARTICl.'I.ATE (XNTKil!
UKVIi <•:
ASPHALT
FLUX -7
J25*-150"F
PLOUINC
STILL
CONTAINING
ASPILV...
.•*
FUEL
ASPHALT HEATEK
Rt'cnvF.RFn nn
WATK,'
AIR
AIR BLOWER
El.nWN ASPHALT
Figure 8.2.-1. Air blowing of Asphalt.3
At the next step, steam heated ilrying-in drums and tht- wet looper provide
the heat and time, respectively, for thr asphalt to penetrate the felt.
The saturate."1 tt-lt then passer, through water cooled rjils and onto the
finish floating !ocper, and then is rolled and cut on the roll winder to
product size. Two common weights of asphalt felt art- 15 and 30 pounds
per J08 square feet (108 square fe?t of felt covers exactly 100 square
feet of roof)
A typical process for manufacturing asphalt shingles, mineral
surfaced tolls and smooth rolls is illustrated in Figure 8.2-3- This
line is sjirnlir to the felt line, except that following the wet looper are
,1 coater, a granule applicator, a press section, water cooled rollers, a
finish floating looper, and either a roll winder or a shingle cutter and
stacker. After leaving the wet looper. the saturated felt passes through
the t-oater. Killed asphalt coating at 180° tu 20!>0C (355° to 400°F) is
released through a valve onto the felt just as it passes into the coatcr,1
Filled .Asphalt is prepared by mixing coating asphalt at 205°C (AOO°F) an-1
8.2-2
EMISSION FACTORS
4/81
-------
VtUT TO CoMTROL
CQUIPtCNT
OUT LOOPCR
BURKR
8.2-2. Schematic of line for manufacturing asphalt saturated felt.1
4/81
Mineral Products Industry
8.2-3
-------
SM IICLE 5I*tK£R
8.2-3. Schematic O' line for rr.anura-ti ring aspna.t shingles, mineral st'^aced rolls, and
roils.'
8,2-4
EMISSION FACTORS
4/81
-------
a mineral stabilizer (iillrr) in approximately equal vroportions. The
filled asphalt is pumped to the coater. Sometimes the mineral stabilizer
is dried at about 120°C (2iOcF) in a d»-yer before mixing with the coating
dsptialt. Heated squeeze rollers in th>? coater distribute the coating
evenly upon the felt surface, to form i thick base coating to which rock
granules, sand, talc, or mica can adhere. After leaving the coater- a
felt to be made into shingles or mineral surfaced rolls passes through
tne granules applicator where granules are fed onto the hoi., coaler)
surface. The granules are pn-ssed ,nto the coating as it passe-i through
squeeze rollers. Sand, talc or mica is applied to the back, or opposite,
side of the felt and is also pressed into the felt surface. Following
the application of the granules, the felt is cooled rapiuly and is
transferred through the finish flowing looper to a roil winder or shingle
cutter.
8.2.3 Emissions and ConLrols
The atmospheric emissions from asphalt roofing manufacturing are:
1. gaseous and participate organic compounds that include small
amounts of participate polycyclic organic matter (PPOM),
2. emissions of small amounts of aldehydes, carbon monoxide and
sulfur dioxide, and
3. particulate emissions from mineral handling and storage.
The sources of the above pollutants ar^: the asphalt blowing stills,
the spturator and coater, the asphalt storage tanks, and the mineral
handling and storage facilities. Emission factors from uncontrolled
blowing and saturating processes for parLiculate, carbon monoxide, and
volatile organic carbon as methane and norunethane are summarized in
Table 8.2-1.
A common method to control emissions at asphalt roofing plants is
completely »,o enclose the saturator, wet looper and coater snd then to
vent thp emissions to one or more control devices (see Figures 8.2-2 and
8.2-3). Fugitive emissions froir. the saturator may pass through roof
vents and other openings in the building, if the saturator enclosure is
rut p operly installed and maintained. Control devices used in the
industry include aftciburners, high velocity air filters, low voltage
electrostatic precipitators , and wet scrubbers. Blowing operations are
controlled by afterburners. Table 8.2-2 presents emission factors for
Lont.rolled blowing and saturating processes.
Particulate emissions associated with mineral handling and storage
operations are raptured by enclosures, hoods or pickup pipes and are
controlled by using cyclones and/or fabric filters with removal
efficiencies of approximately 80-99 percent.
-------
TABLE 8.2-1. EMISSION FACTORS FOR ASPHALT ROOFING MANUFACTURING
WITHOUT CONTROLS3
EMISSION FACTOR RATING: PAKTICULATE- A
OTHER- D
Operatic.r.
Carbon
Particulars monoxide
Volatile
organic compounds
methane
nonmethane
kg/Mg Ib/ton kg/Mg Ib/ton kg/Mg Ib/ton kg/Mg Ib/ton
Asphalt blowing
it
f
Sat'.jrantc 3.6 7.2 O.l4d 0.27d e e
Coating
13.4 26.7
e e
0.94 l.flS 0.93 1.86
Shingle
saturation8 0.25 0.50 0.01 0.02 0.04 0.08 0.01 U.02
Shingle
. h
saturation 1.57 3.14 0.13 0.25 0.11 0.22 0.02 C.03
.References 2 and 4.
Expressed as kg/'.1g (Ib/ton) of asphalt processed.
.Saturant blow oi 1.5 hours.
Reference 2. CO data for uncontrolled emissions from stills was not
obtained during latest test program.
Species data not available for saturant blow. Total organics (as CH4) for
saturant blow are 0 73 kg/Mg (1.460 Ib/'t&n) .
Coating \~l >* of 4.5 hours.
^Expressed as kg/Mg (Ib/ton) of 106.5 kg (235 Ib) shingle produced. Data
from dip saturators.
Data fron» spray/dip saturator.
NOTES: -Particulate polycyclic organic matter is about 0.3 % of
parlirulate tor blowing stills and 0.1 % of participate for raturators.
-Aldehyde emission measurements made during coating blows:
4.6xlO"5 kg/Mg (9.2xlO"5 Ih/ton).
-Aldehyde emissijns ddta taken from one saturator only, with
afterburner the control device: 0.004 kg/Mg (0.007 Ib/ton).
-Species data not obtained for uncontrolled VOC, assumed same
percentage methane/norunethane as in controlled emissions.
8.2-6
EMISSIO.-i FAC'JORS
-------
TABLt: n 2-2. EMISSION FACTORS FOR ASPHALT ROOFIVG MANUFACTURING
WITH
EMISSION FACTOR RATING: PARTICIPATE- A
OTHER- V
Volatile
Carbon organic compounds
Participates monoxide methane nonnethane
Operation kg/Mg Ib/ton kg/Mg Ib/ton kg/Mg Ib/ton kg/Mg Ib/ton
Asphalt blowing
SaturantC 0.25 0.50 0.6 1.2 d d d d
Coating6 0.45 0.89 4.4 8.8 0.05 0.10 0.05 0.09
Shingle
saturation 0.03 0.06 0.45 U.898 O.U8 0.15 0.01 0.02
.References 2 Jn<1 4.
Expressed as kg/Mg (Ib/ton) of asphalt, processed.
.Saturant blow of 1.5 hours.
Species data not available for saturant blow. Total organics (L,S CH4) for
saturanl blow are 0.015 kg/Mf. (0.03 Ih/ton).
-Coating blow of 4.5 iiours.
Expressed as kg/Mg (Ib/ton) of 106.5 kg (235 Ib) shingle produced
(averages of test data from fo.tr plants).
CO emissions data takt.*n from one plant only, with afterburner the
control device. Temperature of afterburner not high enough to convert
CO to C02.
NOTE: Particulate polyrlic organic matter is about C.03 % of particul.ite
for blowing stills and about 1.1 % of particulate for sat.urator;.
4/8J Mineral Products Industry S.i-7
-------
In this industry, closed silos are used for rineral storage, so open
storage piles are not a problem. To protect the minerals from moisture
pickup, all conveyors that aie outside the buildings are enclosed.
Fugitive mineral emissions may occur at the unloading point, depending on
tr:3 type of equipment used. The discharge from the conveyor to the silos
is controlled by either a cy :lone or a fabric filter.
References for Section 8.2
1. John A. Danielson, Air Pollution Eugineej-irg Manual (2d EdLj , AP-iL ,
U.S. Environmental Protection Agency, Research Triangle Pai/k, NC,
May U'73. Ouc of print.
2 Atmospheric Emissions frojn Asphalt Roof ing Processes, EPA Contract
No. 68-02-1321, Pedco Environmental, Cincinnati, OH, Octjber 1V7A.
1. L. W. Corbett, "Manufacture ot Petroleum Asphalt", Bituminous
Materials: Asphalts, Tars, and Pitches, Vo 2, Part ],~New York,
Interscience PubiishTs, 1965.
Background Infcrmatiur fur Proposed Standards Aaphr't Roofin
Manufacturing Industry, EPA A50/3-30-021a, U.S. Enviromontal
Protection Agrncy, Research Triangle Park, NC, June 1980.
8,2-8 ^IMISSIOS FACTORS
-------
8.3 BRICKS AND RELATED CLAY PRODUCTS
8.3.1 Process Description
The manufacture of brick and (elated products such as clay pipe, pottery, and sonu types of refractory brick
involves the mining, grinding, screening, and blendim; of the raw materials, and the lorming. cutting 01 shapmt.
drying or curing, and liring of the final product.
Surface clays at d shaks arc mined in open pits, most Tine clays are found underground. After mining, the
material Is crushed to 'P.niove stones ;md stirred before it passes onto screens that arc used to segregate the
particles by size.
At thj start of the forming process, clay is mixed with water, usually in a pug mill. The three princind,
processes fur Torn,ing brick are: stiff-mud, soft-mud, and dry-process. In the stiff-mud process, sufficient water is
adJed to give the c'ay plasticity; bri'.Ks are then formed by forcing the clay through a die and using cutt.-i wirf t<
separate the bricks. All structural tile and most brick are formed hy ihis process. The soft-mud process is usually
used when the clay contains too much waler for the stiff-m'id ptocess. The clay is mixed with water unlit the
moisture content reaches 20 to 30 percent, and the bricks are formed in maids. In the dry-press process, clay is
mixed with a small amount of water and formed in steel molds b>' applying a pressure of 500 to 1500 psi. The
brick manufacturing piocess is show-i in Figure 8,3-1.
Before firing, the wet Jay jnits that have been formed MIC almost completely dried in diiers that are usually
heated by waste heat from the kilns. Many types of kilns are used lor firing brick, however, the most common are
the turn;] kiln and Ihe periodic kiln. The downdrafl periodic '.iln is a pennantrt brick structure that has a
number of fireholes where fuel is fired into the f-irnace. The hot gases from the fuel are drawn up over the bricks,
town through Ihern by underground Hues, and ou: of the oven to the chinney. Ali'iough f'icl efficiency is not as
hip)' as that of a tunnel kiln because of lower heat recovery, the uniform (cmpera'urc distribution through the
lain lead? to a good quality product In most tunnel kilns, cars ca.r/ing about I 200 b'icks ear'i travel on rails
through ihe kiln at the rate of one 6-foot car per hour. The Tire .-one is located near the middle of the kiln and
remains stationary.
In all kilns, firirg takes place in six steps: evaporation of frie water, dehydration, oxidation, vitrification,
flashi.ig. and cooling. NoirnaJK, gas or residual nil is used for heating, but coal may he usej. Total heating time
varies with the type of product; for example, 9-inch refractory bricks usually roquir: 50 1 > 100 hours, of firing.
Maximum temperatures of about 2000°F ( I090°O are used in firing lOmri'on brick.
8.3.2 Emission:; and Controls' '-1
Partkulaie matter is the primary emission in the manufacture ol biicks. The mrn source of dust is t!ie
material-; handling procedure which includes drying, giinding. sc'csnin^, and storing the raw material.
Combustion ;jn>ducis .ire cmitied from th • fin1! co.isumed in the curing, drying, "iid riring por'ion of the process.
Fluorides, largely in ?;>se
-------
(PS
CRUSHING
AND
STORAGE
(PI
PULVERIZING
scrubbing kiln gar,es with
water; wet cyclonic scrubbers are available tint can remove fluorides with an efficiency of 95 percent, cr higher.
Emission factors for brick manufacturing are presented in Table 8.,) 1, Insufficient data arc available U present
particle size information.
8.3-2
EMISSION FnCTORS
4/73
-------
Tabte 8.3-1. EMISSION FACTORS FOR BRICK MANUFACTURING WITHOUT CONTROLS*
EMISSION FACTOR RATING: C
Fvpcof process
Raw meter ial handling1
Dryers, grinders, etc.
Storage
Curing and firing'*
Tunnel kilns
GastJred
Oil-fired
Coal fired
Periodic kilns
Gas-fired
Oil fired
Coal-fi id
Paniculate?
Ib/ton
96
34
0.04
0.6
1.0A
0.11
0.9
1.6A
ko/MT
48
17
007
0.3
0.5A9
0.06
0.45
0.8A
Sulfur oxides
:soj
Ib/ton
-
kg/MT
-
~ j ~
Nege
4. OS'
72S
Neg
59S
12.0S
Neg
2.0S
36S
Neg
2.95S
6.0S
Cartoon monoxide
(CO)
fb.Vi
—
0.04
Nag
1.9
0.11
Neg
3.2
kg/MT
-
—
0.02
Neg
0.95
".05
Neg
1.6
Hydrocarbons
(HC)
Ib/ton
-
—
002
0.1
06
0.04
0.1
0.9
kg/MT
—
Nitrogen oxides
(NOK)
Ib/ton
-
_ . _
0.01
0.05
0.3
002
0.05
0.45
0.15
1.1
0.9
0.42
1.7
1.4
kg/MT
-
-
0.08
0.55
0.45
C?l
0.85
0//0
Fluorides**
(HF>
IVton
-
_
.0
.0
.0
.0
.0
.0
kg/MT
-
—
•.:.5
0.5
0.5
0.5
0.5
0.5
2
5'
o.
o
(f.
Q.
c
7OneL>::cV «vein>-.> about 6.5 pounds (2.95 kg). Fmssion (sc.ors expressed asurrlj oerunil waight ol brick produced.
bBdsed on data from References 3 and 6 throu(^i 10.
c Based on data from jec'wnson ceramic days and cetnent manufacturing ~.n this publication. Because o! process variation, tome steps rrwv be omitted. Storage
apply only
-------
References for Section 83
1. Air P'dlutam Emission Kattors. Final Report. Resources ReseHich, Inc., Reston. Virginia Prepared for
National Air Pollution Control Administration. Durham, N.C., under Contract Number CPA-22-69-1 19. April
1 970
2. Technical Nines on B'ick a,n! Tile Construction. Stuitur»l Clay Products Institute. Washington, D.C.
Pamphlet Number'.' Scpl 'nrvi I%1.
3. Unpublished control techniques for fluoride emissions. Environments! Protection Agency, Office ot Aii
Programs, Research Tiia ;jjle Park. N C
4. Allen. M. H. Report on Air Polluiion, Air Quality Act of 1"<>7 and Methods ^'Controlling the Oiission of
Paniculate and Sulfur Oxide Air Pullu'jrtv Stuictural Clay Products Institute. Washington. D C. September
S. Norton, F. H. Refractories, 3rd Ed. New York, McGraw-Hill Book Company. 1949.
6. Strnran. K. T. Emissions of Fluorides froin Industrial Proceisos: A Review J. Air Pol. Control Assuc.
7C:>:92-108 Augu?l l')5''.
1. Kirk-Othmcr l'.m:yclopeJia of Chemical Technology. Vol. V, 2nd Ld. New York. Intersciriicc (John Wiley
and Sons, Inc ), 1%4. p 561 567.
8. Wontzcl. K F. Fluoride Emissions ir the Vicinity of Brickworks. Siaub. rj(3):45-50. Maich 1965.
'i. Alien. G. L. i-t al. Control ol M .ailurgicu) and Mineral Duils and 1-umcs in Los Anjivles County. U. S.
Department ol" Inter. or, Bureau or A.mcj Washangtwn, D.C. Information Circular Numbei 7627. April 1951
10. Private LOinmunication between Resources Research, Inc Reslon, Va. and Ihc Slate ol New Jersey Ai'
Pollution Control Program. Trer.un. Julv 20,
8.3-4 EMISSION FACTORS 4/73
-------
B.t. CALCIUM CARBIDE MANUFACTURING
8. A.I General
Cal.ium carbide (CaC2) is manufactured by heating a lime and carbon
mixture to 2,000 to 2,100CC (3,632 to 3,812'F) in an electric arc furnace.
At chose temperatures, the lime is reduced by caibon to calcium carbide and
carbon monoxide, according to clit following reaction:
C,iO + JC - CaC2 + CO
Lime for the reunion is usually made by reducing limestone in a kiln at the
clunt site. The sources of carbon for the reaction are petroleum coke,
cotal lurgical coke or anthracite coal. Because impurities in the furnace
charge retrain in r.he calcium carbide product, the lirce should contain no more
than 0.5 percent each of magnesium oxide, aluminum oxide and iron oxide, and
0.00-'» percent phosphorous. Also, the coV.e charge should he low In ash and
sulfur. Analyses indicate thai: 0.2 to i.O percent ash and 3 to 5 percent
sulfur are typical in petroleum coke. About 99'. kilograms (2,185 Ib) of
lime. 683 kilograms (1,506 Ib) of coke, and 17 to 20 kilograms (37 to 46 Ib)
of electrode paste are requirad to produce one megagram (2,205 Ib) of calcium
carbide.
The process for manufacturing calcium carbide is illustrated in
Figure 3.4-1. Moisture is removed from coke in a coke dryer, while lime--
stone is converted to lime in a lime kiln. Fines from coke drying and lime
operations are removed and may be recycled. The two charge materials are
then conveyed to a.\ electric arc furnace, the primary piece of equipment used
to produce calcium carbide. There are two basic types of electric arc
furnaces, the open furnace, in which the carbon monoxide burns to carbon
dioxide when it contacts the air above the charge, anH the closed furnace, in
which the gas is collected fro-n the furnace and eithpr used as fuel for other
processes or flared. Electrode p.istc composed of coal car pitch binder and
Fi>>iir«.' fc.''i-l. ('.i 1 c in.'ii carhiile rnnnuf nc r. ur inp jir.j- •..-••*•,.
Mincrnl Products Induhtry '.-(.4-1
-------
anthracite coal Is continuously fed into a steel casing wheis it is baked hy
heat fron the electric arc furnace before introduction into the furnace. The
baked electrode exits the steel casing .lust inside the furnace cover and ib
consumed in the calcium carbide production process. Molten calcium carbide
is tapped continuously from the furnact into chili cars and is c'lloweti '"o
cool and solidify. Then, primary crushing of the solidified calci'iin c.^'blrle
by jaw crushers is followed by secondary crushing and screening for :as
completely cooled or may be carried out in an Inert Atmosphere The cairimr.
carbide product is used primarily in acetylene geneiatinr and also as a
desulfurizer of iron.
8.4.2 Emissions and Controls
Emissions froo calcium carbide manufacturing inclv.de partiruia e v.aLtcv.
sulfur oxides, carbon monoxide and hydrocarbons. Particulate usattp.i.' "
emitted from a 'ariety of equipment and operations in the L;
-------
CO
I
i S.4-;. ussier; '•••...TO v, -o? r.>/..f HIM CA.RJH.C:
. , ' .. ,3
3
a
rt>
a-
d
c
n
rr
rr
r J
D.
cc
Un .-.rt /-riled fo.it.ol je »" \ ('.itiij',
EJe'.trie fuinact- ma,ir. srack." 1 .! (74) '..3^' ('.'/o'- ;..' ( "', > ' B..,' C
C.< MB dryav 1 .i1 <2 .;} ').l?. ./. o ,1, (3 ()', ' C,
Tap fii^A vents ',f/ .. d.l'> ,').i' i , ; .. C
i ' i i
Furnace room v ; i^ i
''••''/'' /
PriicaTy and •.econ-'ip.'ry crushing ' N'D ,. < . .r 7 ' .}•>.) < ' j( ' ;'. ;'
Circular rr«'. rgir.;; conveyor ' ND 0 J ," ^fi...4( ' ; <;
a , '- -"- - , • - ' ' -,----'.-- - - -fj , - --
Factors arc in ^g/Mg (It/'.on;' r-i calc^ur1 •<-i•^irte ,i:cv *•;<• • - ;' 1- •• N <>ut . / V
Ele.-'cric furnace: primarily magneej.an : oar>t!U'\df; 'Jit ,j.;»ii -in.'M :.J ;/r.j ,-/.'>' ,>»or; %'.-r.',s'.
'-.arbor), calcium, magnesium, silJ^or., ivon coirpoo-i.'i. Pri'o/'r-'/avd • V.T.UJJI y •;::''•:. r-.i.:* * c.'j <.:iUT •
carbide. Circular cliarpi'.ig crr.veyor? line, coV- ' /
Based on emissions <1nta and •_io?" on a'is'ijiel conirol cf^r-lo::..its. . /'' ' ' /
d.
Uncontrolled. ' / •
f •'
!\.alir.« ii- B for particu.'ate matter emissio.i fattjr, C jtor !ji>JL'. CT V.i ! it . I::t.1.jCi ;:-|'f '.:;•• ;-ie l.t
oper. f^iLuaceb using petroleum coke. ,
f
f ..
-------
References for Section 8.4
1. "Permits to Operate: Airco Carbide, Louisville, Kentucky", Jefferson
County Air Pollution Control District, Louisville, KY, December 16,
1980.
2. "Manufacturing or Processing Operations: Airco Carbide, Louisville,
Kentucky", Jefferson County Air Pollution Control District, Louisville,
KY, September 1975.
3. Written communication from A. J. Miles, Radian Corp., Durham, NC, to
Douglas Cook, U. S. Environmental Protection Agency, Atlanta, GA,
August 20, 1981.
4. "Furnace Offgas Emissions Survey; Airco Carbide, Louisville, Kentucky",
Environmenca'i Consu.1tar.Ls, Inc., Clarksville, IN, March 17, 1975.
5. J. W. Frye, "Calcium Carbide Furnace Operation", Electrir Furnace
Conference Proceedings, American Institute of Mechanical Engineers, New
York, December 9-11, 1970.
6. The Louisville Air Pollution Study, U. S. Department of Health and Human
Services, Robert A. Taft Center, Cincinnati, OH, 1961.
7. R. N. Shreve and J. A. Brink, Jr., Chemical Procpss Industries, Fourth
Edition, McGraw Hill Company, New York, 1977.
8. J. H. Stuever, "Particulate Emissions - Electric Carbide Furnace Test
Report: Mi^wei-t Carbide, Pryor, Oklahoma", Stuever and Associates,
Oklahoma City, OK, April 1978.
9. L. Thomsen, "Particulate Emissions Test Report: Midwest Carbide,
Keokuk, Iowa1', Beling Consultants, Inc., Moline, IL, July 1, 1980.
10. D. M. Kirkpatrick, "Acetylene from Calcium Carbide Is cu Alternate
Feedstock Route", Oil ana Gas journal. June 7, 1976.
11. L. Clarke and R. L. Davidson, Manual fot Process Engineering
Calculations, Second Edition, McGraw-Hill Company, New York, 1962.
8.4-4 EMISSION FACTORS 1/R'*
-------
8.S CASTABLE REFF.ACTORIES
8.S.I Process Description1'3
Castable or fused-caM refracMrles au rnanufacured by carefully blending such components as alumina,
zirconia, silica, chrome, and magnesia; melting the mixture in an electnc ar<~ furnace at tcnipciaiurrs of 3200 to
4500°F (1760 to 2480°C); pouring it .nto molds, and slowly cooling it to the solid state. Fused refractories arc
less porous jnd mare dense than kiln-fired refrzctonss
S.S.I Emissions and Cuitilob1
Paniculate emissions occur during the drying, crushing, handling, and blending of the components; dur-ng the
actual melting process; and in the molding phase. Fluorides, largely in the gaseous form, may also be emitted
during the melting operations.
The general types of participate controls may be use'] on the materials handling aspects of refractory
manufacturing. Emissions from the eiectric-arc furnace, how., r, are largely condensed fumes and consist of very
fine particles. Fluoride emissions can be effectively controlled with a scrubber. Emission factors for castable
refractories manufacturing are presented in Table 8.5-1.
Table 85 1. PARTlCULATE EMISSION KACTORS FOR CASTABLE
REFRACTORIES MANUFACTURING'
EMISSION FACTOR RATING: C
Type of prjcess
Raw material dryerb
Raw material crushing
arid processing0
Electric-arc melting1*
Curing oven*
Molding and shakeoutb
Type of control
Baghouse
Scrubber
Cyclone
Baghouse
Scrubber
-
Baghouse
Uncontrolled
Ib/ton
30
i"i-i
50
0.2
2ti
kg/MT
15
60
25
C.1
12.5
Controlled
Ib/ton
0.3
7
46
C.8
10
-
0.3
kg/MT
0.15
3.5
22.5
0.4
5
-
0.15
8Fluoride emissions from the melt average about 1.1 pounds of HF per ton of melt (O.G6
HF/MT melt). Emission factor! ixprasjed at units per unit wiighi ot fcod material.
bRpfer»ncB 4.
cRfl'eiuricw 4 and 5.
QRe'erencw4 through 6.
5.
2/72
Mineral Products Industn
8.5-1
-------
References for Section 8.5
1. Air Pollutant bniission Factors. Final Report. Resources Research, Inc. Reston, Va. Prepared for National
Air Pollution Control Admin isi rat ion. Durham, N C., undei Contract Number CPA 22-69-119. April 1970.
2. Brown, R. W. and K. H. Sandme; er. Applications of Fused-Cast Refractories. Cheni. Eng. 7ft: I 06-114, June
16 1969.
3. Shreve, R.N. Chemical Proceis Industries, 3rd Hd. New York, McGraw-Hill Book Company. 1967. p. 158.
4. Unpublished data provided by a Corhait Refractory. Kentucky Depai-men' jf Health, Air Pollution Control
Comrfission. Frankfort Kentucky. September 1969.
S. Unpublished stack test dati on refractories. Resources Research, Incorporated. Reston, Virginia. 1969.
6. Unpublished stack test data on refractories. Resources Research, Incorporated Pestan, Virginia. 1967.
8.5-2 EMISSION FACTORS 2/72
-------
8.6 PORTLAND CEMENT MANUFACTURING
86.1 Process Description ' -1
Portland cement manufacture accounts for about 98 peneiit of the cement production in the United Slates.
The more than 30 raw materials us:d to make cement may be divided into four basic components: lime
(calcareous), silica (siliceous), alumina (argillaceous), and iron (ferriferous). Approximately JIOO pounds of diy
raw materials are required to produce I ton of cement. Approximate!) .15 percent of the raw material weight is
remover] is carbon dioxide and water vapor. As shown in Figure 8.6-1. the raw materials undergo separate
Crushing after the quarrying operation, and, when needed for processing, are proportioned, ground, and blended
using either the wet or dry process.
In the dry process, the moisture content of the raw material is reduced to le,s than 1 percent either before or
during the grinding operation. The dried materials .-ire then ptilveri/ed into a powiler and fed directly into a rotary
kiln. Usually, the kiln is a long, horizontal, sleel cylinder with a refractory brick lining. The kilns are slightly
inclined and rotate about the longitudina axis. The pulverized raw materials are fed into the upper end and travel
slowiy to the lower end. The kilns are fired from the lower end so that the hot gases p?&s upward and through ths
law material. Drying, decarbonating, ar.d calcining are accomplished as the material travels through the heated
kiln, finally burning to incipient fusion and lor,mug the clinker. The clinker is Cooled, mixed with about 5
percent gypsum by woighl, and ground to the final product fineness. The cement is then stored for later
packaging and shipment
Wiih the wet process, a sluny is made by adding >vjter to the initial grinding operation. Proportioning may
lake place before or after the grinding step. After the materials are mixed, the excess wyteris removed and final
adjustments are made to obtain a desired competition. THs final homogeneous mixture is fed to the kilns as ,n
slurry of 30 to 40 percent moisture or as a wet filtrate cl about 20 percent moisture. The burning, cooling.
addition of gypsum, and storage are carried out as in the dry process.
8.6.2 Emissions and Controls' '•*
Paniculate matter is the primary emission n. the mannl-iiMiue ot portland cement. Emissions also incluJc Ihc
normal combustion products of the fuel uscJ to suppi; heat r.ir the kiln and drying operations, incl .dinis ox..1es
of nitrogen arid small amounts of oxides of sulfur.
Sources fif dust at cement plants include: (I) quarrying and crushing. (2) raw materi;il storage. (3) grinding and
blending (dry process only), (4) clinker production, (5) finish grinding, ami (6) packaging. The largest source of
emissions within cement plants is the kiln operation, which may bt considered to have three units: the teed
system, the fuel firing system, and the clinker-cooling ,uid h^ndlin^ system. The :>'ost desirable method ol
disposing of the collected dust is 'ejection into the burning zone of the kilii and ;»:od'iciion oi'clinkers from the
dust. If the alk:'!t content of the raw materials is too higii. however, some ot the d.ist is discards j ;;: leached
before returning lo the kiln In many instances, the maximum allowable jikjli ..onleii: of 0,6 ptrtceii. (calculated
as sodium oxide) restricts tin1 amount of dust thai can he re ycled Additiorul sources of dust emissions arc riw
material storage piles, convey* rs, ?.!O!jge silos, and loadin^'iml Aiding tucili'ies
The complications of kiln ! urninp and lm> large volumes of materials Innu'led have led to the adoption oi
injiiy control w stums lo- dus'. collection. Depending upon the emission. Jie temperature of I he e'tlucnts ii; ihe
4/73 Mineral Products Induhtry 8.6-1
-------
c
QUARRYING
RAW
MATERIALS
*
PRIMARY AND
SECONDARY
CRUSHING
RAW
MATERIALS
STORAGE
%\
RAi
MATERIAL
PROPORTIONED
GRINDING
MILL
AIR
SEPARATOR
DUST
COLLECTOR
•ET PROCESS
£
35
•j±
5
z
o
70
RAi
MATERIAL
PROPORTIONED
GRINDING
KtLL
D
^5
-------
plant. In question, and the particulate emission standards In Che community, the
cement industry generally uses mechanical collectors, electrical pr*eipitator»,
tabric filter (baghouae) collectors, or combination* of these devices to control
eoisalona.
Tabli.' C.6-1 summarizes emission factors for cement manufacturing and also
includes In footnote d typical control efficiencies of partlculate emissions.
Table 8.6-2 indicates the particle size distribution for participate emissions
from kilns and cement plants before control systems are applied.
TABLE 8.6-1.
EMISSION FACTORS TOR CEMENT .'
WITHOUT CONTROLS* »b»c»°
Paniculate*
Sulfi-.r dloKlde*
Nt'Mral source
kg/US
Ib/ton
(ta coubuallon
ib/ton
Oil conbuutlon
Ib/ton
Coal combuation
k«/Hg
Ib/ton
Nitrogen oxide*
Ib/tcrn
EMISSION FACTOR RATING: B
Dry Prutieaa
Uet Prucee*
Pollutant Dryer*, Dryera,
Kllna grtnd-ar*, etc. Ullna grinder*, etc.
122. n
141.0
5.1
10.2
2.IS*
4.2S
3.AS
(.85
1,3
2.6
9fc.fl
!1*.0
azd.o
5.1
10.2
Nog
N.R
i'.IS
4.2S
J.4S
6.85
1.3
2,6
-.2.0
Ih/toD
0.06
0.12
0.02
0.04
0.05
0.10
0.01
0.02
*0n* barrel of c***nt v*lghs 171 *g (176 pound*}.
bThent HHlaiLon factor* Include emlnloni fron la»l coabuctlon. which thould not
tt calculi ted »«paracaly.
1-2.
factor* axpT*»i*d in might par unit weight of c*»>nt p'oduced. Oa»h
** no available data.
coilactlon «fflcl«ncl«i for Itilna, dryari, grlndara, ate., are: aulti-
80%; rlactroacatic praclptcator*, 951; «l*ctroat«tlc pr*clpltatara with
miItlcyclonel, 97.51; fabric filter unita, 99.81.
'ft* sulfur dioxlJ* factor* preisntad tak* Intu account tha raactlona xlth tha a1.k-
allna dmita uhan no haghouaei ar* uiad. 111th baghouaea, approximately 50Z aora SOj
la ramoMad bacaja* of ra*cctoni with thai alkatlna partlculata filter c*kc. W»o
n:t* iMc cha total 302 froai tha kill, la dakemlned by aiming aaiaalon ccntrlbu-
rlctu froB th* nlnaral aourca and th« pproprlate fu«l.
STTi**a ealcalona ara Che raiuLt of aulfur balng praia'it in tha raw iiatarltlt and are
Cbuf d^pandint upon aourca of th* rm M«carltli uaad. Tha ' .\ k|/Mg (10.2 Ib/ton)
ftietara accojnt for part of tht available collar retain!r\| bthlnd in tha product
baeauaa of It* aitmlln* nature and affinity for Sti2-
^Negligible,
13 " S aulfur ID fuel.
jRlferenc.ee 7-0.
12/81
Mineral Products Industry
8.6-3
-------
TABLE 8.6-2. SIZE DISTRIBUTION OF DUST EMITTED
VT.OM UNCONTROLLED KILN OPERATIONS * • ">
Parcicle size, Kiln dus: finer than corresponding
microns particle 3lze,%
60 93
50 90
40 84
30 74
20 58
1C, 38
5 2?
I 3
Sulfur dioxide may be generated from t.he sulfur compounds In Che ores as
will as from combusi-in of fjel. The sulfur content of both ores and fuels will
vary from plant to plant and with geographic location. The alkaline nature of
the cement, however, provides for direct absorption of SC>2 into the product.
The overall rontrol inh€:reni. In the procnss is approximately 57 percent or
greater of tbe available sulfur In ore and fuel if a baghouae that allows the
S02 to come in contact with the cement dust is used. Control, of course, will
vary according to the alkali and sulfu. corte.it of the raw scaterials and fuel.
References for Section 8.6
1. T. E. Kreichelt, D. A. Kemnltz, and S. T. Cuffe, Atmospheric Emissions
from the Manufacture of Portland Cement, U.S. 04EW, Public Health Service,
Cincinnati, OH, PHS Publication NumbTr~999-Al>-17, I9b?.
~, Unpublished standards of performance for new and substantially modified
Portland cement plants, U.S. Envl ronmental Protection. Agency, Bureau of
Stationary Source Pollution Control, Research Triangle Park, NC, August
1971.
3. A Study of the Cement Industry ir^ the State of Missouri, Resources Re-
search Inc., Reston, \M, prepared for the Air Cor.«t.rva;lon Commission of
r.he State of Missouri, December 596;'.
4. Standards oi Performance for Ngw Stationary Sovirce;, U.S. Environmental
Pro"t7cTior.~~Ager.cy, Feder.il Re^iiTrer 36(247,Pt II): D-cember 23, 1971.
5. Particulate Pollutant SystfjTn Study. Miilwest Rc.searcti Institute, Kansas
City, MO, prepared for U.S. Environmental Protection Agency, Air Pollution
Control Office, Research Triangle Park, NC, under Contract Number CPA-22--
69-104, May 1971.
6. Restriction of Emissions 1 rom Portland Cfe-.-nent Works, VDI Richtllnien,
Dusseldorf, Germany, February 1967.
7. Emission Tests Nos. 71-MM-02, 71-MM-03 and 71-MM-05, Office of Air Qual .ty
Planning *nd Standards, ReHearr',, Triangle Park., NC, March-April 1972.
8> Control Techniques for Lead Air Emissions, EPA 450/2-77-012, U. S. Environ-
mental Protection Agency, Research Triangle Park, NC, December ]972.
8.6-4 EMISSION FACTORS 12/81
-------
8.7 CERAMIC CLAY MANUFACTURING
8.7.1 Process Description1
The manufacture of '.crurrac clay involve* the conditioning of the basic ores by several ne'.hods. These include
the separation and concentration of the minrrMs by screening, floating, wet and Iry grinding, and blending of the
desired ore varieties. The basic raw materials in ceramic ctjy manufacture "re Itaolinite (AhOj- 2Si0212HiO)
anJ mcntmorillonite |(Mg, Ca) O-Al20v5Si02'iiH2O] clay:. These clays a;e refined by separation and
bleaching, blended, kiln-dried, arid formed into such -terns as whitc.ware, heavy clay products (brick, etc.),
various stoneware, and other products such as diatomaceous earth, v hich is used as a filter aid.
8.7.2 Emissions and Controls'
Emissions consist primarily ot participates, but sane fluorides and acid gas?., are also emitted in the drying
process. The high temperatures of t'ie firing Idlns are also conducive to the fixation of atmospheric nitrogen and
the subsequent release of NO, tut no published information has been found for gaseous emissions. Particulars
are also emitted from the grinding process and from storage of the g: jund product.
Factors affecting emissions include the amount <^f material processed, the type of grinding (wet or dry), the
temperature of '.he drying kilns, the gas velocities and Row direction in the kilns, am! the amount of fluorine in
the ores.
Common control techniques include settling chamber?, cyclones, wet scrubbers, electrostatic pncipitalcrs. and
bag fillers. The most effective control is provided by cyclones for the coarser material, followed by we scrubbers.
big filler:., or rlecujsuuic precipitators for dry dust. Emission factors for ceramic clay manufacturing are
presented in Table 8.7-1.
Table 8.7 1. PAHTICULATE EMISSION FACTORS FOR CERAMIC I.LAY MANUFACTURING'1
EMISSION FACTOR RATING: A
Type ot process
Dryinrd
Grinding6
Storage0
UncomroM .d
Ib/ton
70
76
34
kg/MT
35
38
17
Cyclone0
Ib/ton | kg.'MT
,8
13
8
a
9.5
4
Multiple-unit
cyclone and scrubber0
Ib/ton
/
-
kg/MT
35
~
aETiiii on
S excused as urils pei uni! weigh- of input ID process
Approximate cci'eciion eli> 'ency 75 percent.
'Approximate collection elticiency 90 perci nt
^Relerfnces 2 through 5.
"Reference ->,
2/72
Mineral Products Industry
8.7-1
-------
References for Section 8.7-1
1. Air Pollutant Emission Factors. Final Report. Resources Research, Inc. Reston, Va. Prepared for National
Air Pollution Control Administration. Durham, N.C., under CoiUract Nurobei CPA-22 69-119 Apnl 1970
2. Allen, G L el a!. Control of Metallurgical and Mineral Dust5. and Plants in Lcs Angeles County. Dercartmcnt
oi Interior, Bureau of Mines. Washington, b.C Information Circular Number 7627. April 1952.
3. Private Communication beivven R.;sourccs Re * a red. Incorporated, R«slon, Virginia, and the State of New
Jersey Air Pollution Control Program, Ticncca, N"w Je/sey. July 20, 1969.
4. Henn, J. J. et al. Methods for Producing Alumina fron; Clay: An Evaluation of Two Lime Sinler Processes.
Department of Interior, Bureau of Mines. Washington, D.C. Report of Investigations Number 7299.
September 19b:>.
S. Peters, F. A. et al. Methods for Producing Alumina from Clay: An Evaluation >f the Lime-Soda Sintrr
Process. Department of Interior, Bureau of Mines. Washington, D.C. Report of Investigation Number 6927.
1967.
8.7-2 EMISSION F\CTORS 2/72
-------
&8 CLAY AND FLY-ASH SINTERING
8.8.1 Process Description1
Allhough the processes for sintering Hy ash and clay are similar, there are some distinctions that justify a
separate discussion of each process. Fly-ash sintering plants are generally located near the source, with the IIy ash
delivered to a storage silo at the plant. The dry f!y ash is moistened with a water solution cf lignin Jnd
agglomerated into pellets or balls. This mateiial goes Ic a traveling-grate sintering machine where direct contxot
.vith hot combustjon gases sinters the individual particles of the pellet and completely burns off the residua!
carbon in the fly ash. The product is then crushed, screened, graded, and s'ored in yard piles.
Clay sintering involves the Hri :% off ol en»"»in.ed volatile matter. It is desirable that the clay contain g
sufficient amount of volatile matter so that the resultant aggregate will not be too heavy. It is thus souetimes
necessary to mix the clay with finely pulverized coke (up to 10 percent coke by weight).2-3 In the sintering
process the clay is first mixed with pulverized coke, if necessary, and then pelletized. The clay is next sintered in
a rotating kiln or on a traveling grate. The sintered pellets are then crushed, screened, and stored, in a procedure
similar to that for fly ash pellets.
8.8.2 tmissions and Controls'
In fly-ash iiuiering, improper handling of the fly ash creates a dust problem. Adequate design features,
including fly-ash welting systems and particulate collection systems on all transfer points and on crushing and
screening operations, would greatly reduce emissions. Normally, fabric filters are used to control emissions from
the storage silo, and emissions are low. The absence of this dust collection system, however, would cieate a major
eir.bsion problem. Moisture i* added at the point of discharge from the silo to the agglcnoerator, and very rew
emissions occur There. Normally, there are few emissions from the sintering machine, but if the grate is not
properly maintained, a cuit problem is creited. The consequent crushing, screening, handling, and storage of the
sintered product also create dust problem*.
In clay sintering, the addition of pulverized coke presents an emission problem becaii,f the sintering of
coke-impregnated diy pellets produces more particulate emissions thzr. the sintering of nr.ura! cla). 1 he ci jivhing,
screening, handling, and storage of the sintered day pellets creates dust problems similar to ihose encountered in
fly-asn »if.::r'ng. Emission iac'.nrs for btxh clay and fiy-ash sintering arc shown in Table 8,8-1.
2/72 Mineral Products Industry 8.8-1
-------
Table 83-1. PARTICULATE EMISSION FACTORS FOR
SINTERING OPERATIONS*
EMISSION FACTOR RATING: C
Type of material
Fly ashd
CUy mi-tri wiir> roke'-s
Natural clavh''
Sinterinq operation'*
Ib/tcn
no
41
12
xg/MT
55
2C
6
Crushing, screening,
ani! yard storage*"-0
lb/:on
e
15
12
kg/MT
e
t.b
6
'Emission factors enpiauod as units per «inri weiph' tf finiihwl prrhluct
^Cvcloncs would reduce this emission bv about 80 perrert
Sciul/bers mould reduce this emution by about 90 ptiCent
cBI.
' 90 percent ciay, 10 psrcent pjlwnied ccke; travedrg^rate. urigle-oajj, up-dra*l simenng
nachinc.
'Heferencei 3 rh.-iL^h b
Rotar/ dryer jiPterer
' Reterence 2.
References for Section 8.8
1. Air Pollutani Emission Factors Finai Report Resource!: Research, li.c. Resten. Vi. Prepared for National
Air Pollution Control Admin jsual ion, Duihani, N.C., undei (onlraa Number CPA 22-f»9-l 19. April I1) 70.
2. Comjnuni''alioii between Resources Research. Incorpoiaied. Kesion. Virginia, and .1 clay sintering firm
October 2. 1 969.
3. Communication between Resources Research. Incorporated. F.stnn, Virginia, and an anonymous Ait
Pollution Control Agency. October 16, 1%9.
4 Henn, J J . et al Methods lor Producing Alumina from Thy An F1 !^n!ior> of Two I imc Sinter P>u.-.eFscs.
Departm«ni of the Inicrior. Bureau of Mines. Wrishingion D.f. Report of Investigation Numbc' 7299.
September 1
5. PcK'rs, F. A. ct ai. Methods for Prod-iung Alumina from Clay: At. Evaluation of the '.irne-Soda Sinter
Proceis. Department of the Interiof, Hurcau of Mines Washingion, L.C. Report of Investigation Number
6927. 1967.
8.S-2
EMISSION FACTORS
2/72
-------
8.9 COAL CLEANING
-i ry
8.9.1 Process Description1'
Coal cleaning Is a process by which impurities such as sulfur, ash
and rock are removed from coal to upgrade its value. Coal cleaning
processes are categorized as either physical cleaning or chemical clean-
ing. Physical coal cleaning processes, the mechanical separation of
coal from its contaminants using differences in density, are by far Che
major precises in use today. Chemical coal cleaning processes are not
commercially practical and are therefore not included in this discussion.
The scheme used in physical coal cleaning p-.ucfcsses varies among
coal cleaning plants but can generally be divider, into four basic phases:
Initial preparation, fine coal processing, coarse coal processing, anil
final preparation. A sample process flow diagram for a physical coal
cleaning plant is presented in Figure 5.9-1.
In the initial preparation phase of c^aa cleaning, the raw coal is
unloaded, stored, conveyed, crushed, and classified by screening into
coarse and fine coaJ fractions. The size fractions are then conveyed to
their respective cleaning processes.
Pine conl processing and coarse coal processing use very similar
operations and equipment to separate the contaminants. The primary
differences are the severity of operating parameters. The majority of
coal cleaning processes use upvrd currents or pulses of a fluid such as
water to fluidize a bed of crushed coal and impurities. The lighter
coal particles rise and are removed frcm the top of the bed. The
heavier inpurities are removed from the bottom. Coal cleaned ir. the wet
processes then must be dried in the final preparation processes.
Final preparation p /ocesses are used to remove rcoist:ure from coal,
thereby reducing freezing problems and weight, and raising the heating
value. The first processing step is dewateiring, in which a major por-
tion of the water is removed by the use of screens, thickeners and
cyclones. The second step is normally thermal drying, achieved by any
one of three dryer types: fluidized bed, flash and rrultilouvered. In
the fluidized bed dryer, the coal is suspended anil dried above a per-
t'or-^.tod plat, by rising hot gases. In the flash dryer, coal is fed into
a stream of hot gases, for instantaneous drying. The dried real and wet
gases are drawn up a dryinx c lurar and into a cyclone for separation.
In the multilouvered dryer, hot gases arc passed thr -ugh a falling
curtain of coal. The coal is raised by flights of a specially c"e igned
conveyor,
d.9.? Emissions aid Controls '
Emissions from the initial coal preparation phase of either wet or
dry processes consist primarily of fugitive particulates, as coal dust,
from roadways, stock piles, refuse areas, loaded railroad cars, conveyor
2/8O Mini-ial Proilnci.s lmlu*ln K.*M
-------
Storage
r~u
Ca;>]
linlu.idlnj;
-r
'-rushing
i ...
Dryer
I "diticulate
1 i CmrrolB
I
£
SL Cecil 1 nt
Fine
Coal
C
Class!flritloi
i T
Cn«
Cyclone
Coal
Fine a
t
1'ln*
Coal
Jturae*
*
ntru *f
Mecia
ewaterlng
Cor i ae
,r"
\Xk i
Figure 8.9-1. Typical coat cleaning plant piocess flow diagram.
rO
-------
belt pouroftr, crushers, and classifiers. The major control la
used to reduce these emissions is water wetting. Another technique
applicable tc unloading, conveying, crushing, and screening operations
involves enclosing che process area and circulating air from the area
through fabric filters.
Table 8.9-1. EMISSION FACTORS FOR COAL CLEANING3
EMISSION FACTOR RATING: B
— ~ — _ .Operation
Pollutant"" ~-~-—-___
Particulates
Before Cyclone
After Cyclone
After Scrubber
After Cyclone
After Scrubber
NO ^
X
After Scrubber
vock
Aft«r Scrubber
Fluid ized
And Flush Mulcllcuvered
Ib/ton k^/MT
20b
12*
0.05e 0
0.43h Q
0.25 0
0.14 0
C.10 0
10b
6e
.C5e
.22h
.13
.07
.05
Ib/ton kg/MT
16b 8b
10f 5f^
0.4f 0.2f
.1
Ib/ton kg/MT
25C 13C
8C 4C
O.].f 0.05C
— —
_
- -
— -
-
-
Emission factors ex^rtssed as unit) per weight of coal dried.
References 3 and 4.
p
.Reference ;.
Cyclones
-------
The major source of emissions from the fina.l preparation phase is
the thermal dryer exhaust. This emission stream contains cc.'.l particles
entrained in the drying gases, in addition to the standard products of
~oal combustion resulting from tuning coal to generate the hot g^ses.
Factors for the»a emissions are presented in Table 8.9-1. The moat
common technologies used to control this source arc v:nturi scrubbers
and mist elininators downstream from the product recovery cyclones. The
particulate control efficiency of these technologies ranges from 98 to
99.9 percent. The venturi scrubbbers also have an NO removal efficiency
of 10 to 25 percent, and an SC>2 removal efficiency ranging from 70 to 80
percent for low sulfur coals to 40 tc 50 percent for high sulfur coals.
References for Section 8.9
1. Background Information far Establishment of National ^tar.dards uf
Performance for New Sources: Coal Cleaning Industry, Environmental
Engineering, Inc., Raine-.ville, FL, EPA Contract No. CPA-70-1''2,
July 1971.
2. Air Pollutant Ernisjalor.s Factors, National Air Pollution Control
Administration, Contract No. LPA-22-69-119, Resources Research
Inc., Reston, VA, April 1970.
3. Stack TF • Results on Thermal Ccal Dryers (Unpublished), Bureau rf
Air Pol ion Control, Pennsylvania Department of Health,
Harrisbur~, PA.
4. "ninherst's Answer to Air Pollution Laws", Coal Mining _and_
Processing, 7(2):26-29t February 1970.
5. D. W. Jones, "Dus>. Collection at Moss No. 3", Mining Congress
Journal, 55(7):53-56, July 1969.
6. Elliott Northcott, "Dust Abatement at Bird Coal", Mining Congress
Journal , 5_3:26-29, November 1967.
7. Richard W. Kling, Emissions from the Ijiand Creek Coal Conpany Coal
Procersinj; Plant, York Research Corporation, Stamford, CT,
February 14, 1972.
8. Coal Preparation Plant E;nisFion Tests, Consolidation Coal Company,
Bi_sh_op, Wnst Vi.rfiinia, EPA Contri^t :-.o. 68-02-0233, Sc..tt Research
Laboratories, Inr.., Plumstepclville, PA, November 1972.
9. Coal Preparation Plant Emission Tests, Westmoreland Coal Company,
Wentz Plant, EPA Contract No. 68-02-0233, Scott Research
Laboratories, Inc.. Plumsteadville, PA, April 1972.
10. Background Information for Standards or Performance: Coal
Preparation Plants, Volume 2: Test Data Summary,
F.PA-.'i50/2-74-0?-lh, U. S. Environmental Protection Agency, Research
Triangle Park, NC. October 1974.
»••>-! KMISMON F.UVrOKS 2/K(l
-------
8.10 CONCRLTF BATCHING
8.10.1 Process Descriptioni "•
Concrete batching involves the proportioning of sand, gravel, and cemeni hy means of weigh hoppcra and
conveyors into a mixing receiver such as a transit mix truck. The required amount of water is also discharged into
the receiver along with the dry materials. In some cases, the concrete is prepared U>i :m-site bui!d:ne construction
woi'x or for the manufacture of concrete products such as pipes ana O a typi-
cal value.
hRefarence 4.
2/72
Mineral Products Industry
8.10-1
-------
References for Section 8.10
1. Air Polluiaril iiirusiion t-ac.or;. Hn.il Report. Kesources kcsearcii Inc. KCiton, Va. Prepared for National Air
Pollution Control Adminii.ratiiin, Durham, N.C., under Contract Number CPA-22-69-11 9. ApriJ 1970.
2. Vincent, E. J. and J. L. McGinn1.y. Concrete Batching Plants. In: Air Pollution Engineering Manual
Danielson, J. A. (ed.). U.S. DHEW. PHS, National CcntiT fo; Air Pollution Control. Cincinnati, Ohio. PHS
Publication Number 999-AP-40. ]
-------
8.11 GLASS FIBER MANUFACTURING
8.11.1 Gener.-l
Class fiber manuiacturing is the high temperature conversion of various
raw materials (pre.lonunantly borosil icate,;) into a homogeneous melt, followed
by the fabricatiun of this melt into glass fibers. The two basic types of
glaas fiber products, textile and wool, are manufactured by similar pro-
cesses. A typical diagram of these processes is ihown in Figure 8.11-1.
Glass fiber production can be segmented into three phases: raw materials
handling, glass melting and refining, and fiber forming and finishing, this
last phase being slightly different in textile and the wool glass fiber
production.
Raw Materials Handling - The primary component of glass fiber is sand,
bir it also includes varying quantities of feldspar, sodium sulfate, an-
hydrcus borax, boric acid, and many other materials. The bulk supplies are
received by rail car. and truck, and the lesser volume supplies are received
in drums and packages. These raw materials are unloaded by a variety of
methods, including drag shovels, vacuum systems and vibrator/gravity systems.
Conveying to and from storage piles and silos is accomplished by belts,
Bcrews and bucket elevators. From storage, tne materials are weighed
according to the desired product recipe and then blended well before their
introduction into the melting unit. The weighing, mixing and charging
Derations may be conducted in either batch or continuous mode.
Glass Melting And Refining - lu the glass melting turnace, the raw
materials are heated to temperatures ranging from 1500° to 170U°C (2700° to
3100°F) and are transformed through a sequence of chemical reactions to
molten glass. Although there are many furnace designs, furnacoj .ire gener-
ally large, shallow and well insulated vessels which are heated from above.
In operation, raw materials arp introduced continuously on tor> of ^ bed of
molten glass, where they slowly mix and dissolve. Mixing is effected by
natural convection, g.ises rising from chemical reactions, and in some
operations, by air injection into the bottom of the bed.
Glass melting furu_res> can bu categorized, by their fuel source and
me^hoU of he-t application, into four types: recuperative, regenerative,
unit, .jar.' electric melter. The recuperative, regenerative, and unit melter
furnaces ran be fue^d by either 333 or oil. The current trend is from gas
fired to oil fired. Recuperative furnaces use a steel heat exchanger,
recovering heat from the exhaust ga?es by exchange with tlic combustion air.
Regenerative furnaces use a lattice of brickwork to recover waste neat from
exhaust gases. In the initial mode of operation, hot exhaust gases are
routed through a chamber containing a brickwork lattice, while ronbustion
air is heated by passage through another corresponding brickwork littice.
About every twenty minutes, the air flow is reversed, so that the combustion
air is always lu-ing passed through hot brickwork previously heated by exhaust
gases. Electric furnaces melt glass by passing an elertrir current through
the melt. Electric furnaces ate either hot top or cold top. The former use
gas for auxiliary hating, and the latter use only the electric current.
9/85 Mineral Products Industry h.11-1
-------
Raw mactnals 1
receiving and hcndllns 1
i
Crushing, veiflhinq, mixing
Sizing, binding addition
Binder
addition
Compression
Oven curing
i
Ovi-.- Irving
Cooling
Over :urlng
Faoncation
.na t ion
Packaging
Figure 8.11-1. Typical flow diagram of Die glcss fibfr
production process.
. 11 - r-
F.MISSION FACTORS
-------
Electric furnaces are currently used only for wool glas£ fiber production,
because of the electrical properties of the glass formulation. Unit melters
are used only for th
-------
o
as
n
MOLTEN
CLASS
/ I « , 1 I I I \
• I (I . / \ ^ \ \ V\
'' i \ i \ V
• ,
*
ATTENUATION AIR
SPINNER
BUCKET
BINDER SWAY
GLASS FIBERS
T-) CUKi«C
o • o
K>RMiNi. rxHAIJSI IS I'LM.LEP THROUfiH
IMF i DN'vFYOR AM!> HA I BY i-A^S
Figure 8.11-2. A typical rotary spin process.
-------
attenuated (stretched to the point of breaking) by high velocity, hot air
and/or a flame. After the gla^s fibers are created (by either process) and
.sprayed with the hinder solution, they arc collected by gravity on a conveyor
belt in the form of a max..
The conveyor carries the newly formed mat through a large oven for
curing of the thermosetting binder and then through a cooling section where
ambient air is drawn dowr through the mat. Figure 8.11-3 presents a
-.schematic drawing of the curing and cooling sections. The cooled mat remains
on the conveyor for trimming of the uneven edges. Then, if product i;pecifi-
ia Lions require it, a backing is applied with an adhesive to form a vapor
barrier. The mat is then cut into batts of the desired dimensions and
packaged.
Textile Glass Fiber Forming And Finishing - Molten glass fro..: either
the direct melting furnace or the indirect marble melting furnac-j is tempera-
l.UiTf regulate^ to a precise viscosity arid delivered to forming stations. At
the forming stations, the molten glass is forced through heated platinum
bushings containing numerous very small orifices. The continuous fibers
emerging from the orifices are drawn over .1 roller applicator which applies
» co.'itint; of water soluble sizing and/or coupling agent. The codted fibers
are gathered --nd wound into a spindle. The spindles of glass fibers are next
conveyed to a drying oven, where moisture is removed from the sizing and
coupling agents. The spindles are then sc-'t to an oven to cure the coatings.
The final fabrication includes twisting, chopping, 'weaving and packaging of
the fiber.
8.11.2 Emissions And Controls
Emissions and controls for glass fiber manufacturing can be categorized
by the three production phases with which they are associated. Emission
factors for the glass fiber manufacturing industry are given in Tables 8.11-1
and 8.11-2.
Raw Materials Handling - The major emissions from the raw materials
handling phase are fugitive dust and raw materi.iJ particles generated at each
of the material transfer points. Such .1 point would be where sand pours from
a conveyor belt into a storage silo. The two major control techniques are
vet or very noist handling and fabric filters. When fabric filters are used,
the transfer poin'.s are enclosed, and air fron the transfer area is
continuously circulated through the fabric filters.
Glass Melting And Refining - The emissions from glass melting and
refining inclaJe volatile nrgaric compounds from the melt, raw material
particles entrained in the furnace flue gas and, if furuaces are heated with
fossil fuels, combustion products. The variation in emission rat«?s among
furnaces is attributable to varying operating temperature, raw material com-
position, fuels, and flue gas flow rates. F.lectric furnaces generally have
the lowest emission rates, because of the lack of combustion products and of
the lower temperature of the melt surface caused by bot'.om heating. Emission
control for furnaces is primarily fabric filtration. rubric filters are
effective on particulates and SO and, to a lesser extent, or CO, NO and
x x
fluorides. Efficiency on these compounds is attributable to both condensa-
tion on filterable particulates and chemical reaction with particulates
9/85 Mineral Products Industry ;^.11-
-------
C/l
C/J
o
25
O
O
90
in
COOLING AIR
CURED MAT
CURING AIR
COOLING
EXHAUST
CURINH KXHAUST
^ TO CONTROL DEVICE
CTNCT.UDKS FtTH.
C UNhUM :<1N (./I
3
OC
Figure 8 11-3. Side view c.f curing oven (indirect heating) and looling section.
-------
trapped on the filters. Reported fabric filter efficiencies on regenerative
and recuperative wool furnaces are for particulatrs, 95+ percent; SO ,
99+ percent; CO, 30 percent; and fluoride, 91 to 99 percent. Efficiencies
on other furnaces arc lower because of lower emission loading and pollutan'.
characteristics.
Wool Fiber Forming And Finishing - Emissions generated during the
manufacture of wool fiberglass insulation include solid particles of glass
and binder resin, droplets of hinder, and components of thp hinder that have
vaporized. Glass particles may he entrained in the exhaust gas stream during
forming, curing or cooling operations. T-'jst data show that, approximately
99 perrent of the total emissions froni the production line is emitted from
the forming and curing sections. Even though cooling emissions are negli-
gible at some plants, cooling emissions at others inay include fugitives from
the curing section. This cuiruningl ing of emissions occurs because fugitive
emissions from the open terminal end 'il the curing oven may be induced ihto
the cooling exhaust ductwork and be discharged into the atmosphere. Solid
particles of resin may be entrained in the gas stream in either the curing
or cooling sections. Droplets of organic binder may be entrained in the gas
stream in the forming section or nay be a result of condensation of gaseous
pollutants as the gas stream is cooled. Some of the liquid binder used in
the forming section is vaporized by the elevatec temperatures in the forming
and curing processes. Much of the vaporized material will condense when the
gas strram cools in the ductwork or in the emission control device.
Partirulate matter is the principal pollutant that has been identified
and measured at wool fiberglass insulation manufacturing facilities. It was
known that come fraction of th^ particulate emissions results from condensa-
tion of organic compounds used in the binder. Therefore, in evaluating
emissions and control device performance for this source, a sampling method,
F.PA Reference Method 5E, 'as ustd that permitted collection and measurement
of both solid particles and condensed particulate material.3
Tests were performed c!"ring the production of R-ll building insulation,
P.-I9 huiHing ^ nsiilation, ductboard and heavy density insulation.4 These
products. vhich. =u fount for 91 percent of industry production, had densities
ranging from 9.1 to 12.3 kilograms per cubic meter (kg/m3) for R-ll, 8.2 to
9.3 kg/m3 for R-19, and 54.5 to 65.7 kg/m3 for ducthcard. The heavy density
insLlatinn had a density of 118.5 kg/m3. (The remaining 9 percent of
industry wool fiberglass production is n variety of specialty products for
which qualitative and quantitative in format]on is not available.) The loss
on ignition (LOTJ of the product is a measure of the amount of bir.dcr
present. The LO[ values ranged from 3.9 to 6.5 percent, 4.5 to 4.6 percent,
and 14.7 to 17.3 percent, respectively. The LOI for heavy density it.
10.6 percent. A production line may be used to manufacture more than one of
these product types because the processes involved do not differ. Although
the data base did not show sufficient d if fe.:enr:es in mass emission levels to
establish separate emission standards for each product, thp uncontrolled
emission factors are sufficiently different to warrant their segregation for
AP-42.
The level of emissions control found in the wor.-l fiberglass insulation
manufacturing industry ranges from uncontrolled to con.rol of forming, curinr
9/85 Mineral Products Industry fi.11-7
-------
TABLE 8.11-1. EMISSION FACTOHS FOR CLASS FIBER MANUFACTURING WITHOUT CONTROLS*
2
IT.
—i
O
2
J
r-.
O
w
lln 1 o >,is-u!ii I DIP 1 Lrr
Glass furnacp - Ipxtilp
RrTuitrt .it IVP
Rf.»>»t'npr .it ivp
Inn 1 mpltpr
rnrTiMi- - wool
flame ittpnuation
l-'or^niiR - textile
Hvrn C'jriiift - wool
Klairr attenualian
')/f»n curiiift and
rnol inj" - tpxt i i e
Piir 1 1 nil ill PS
Ib/ton kR/rTpt
i . 0 1 . ri
0.2 0.1
0 . ft !; . 1
NPR NPR
0.3 C.2S
22 ;i
25-10 13-15
g
Klour ides
In/ton kft/NR
ri
ri
d
d
O.r:02
012
on
r .12
2
2
2
'
d
p
rl
aiM>.
' J'r.f ,-r, ,,,-r 1
-------
and cooling emissions from a line. The exhausts from these process opera-
tions may be controlled separately or in combination. Control technologies
currently used by the industry include wet ESPs, low and high pressure drop
wet scrubbers, low and high temperature thermal incinerators, high velocity
air filters, snd process modifications. These added control technologies
are available to all firms in the industry, but the process modifications
used in this industry are considered confidential. Wet ESP.= are consider*, u
to be best demonstrate^ technology for the control of emissions from wool
fiberglass insulation manufacturing lines.4 Therefore, it is expected that
post new facilities will b« controlled in this manner.
Textile Fiber Forming And Finishing - Emissions from the forming an-1
finishing processes include «;lass fibe-r .-.j. i id es , resin particles, hydro-
carbons (primarily phenols and aldehyde?), -uid combustion produ< '.: from
dryers and ovens. Emissions are usually lower in the textile fi:-er glass
prnrc'ss than in the wool fiberglass process because of lower turbulence in
the forming step, roller application of costings, and use of much less
coating per ton of fiber produced.
TABLE 8.11-2. UNCONTROLLED EMISSION FACTORS FOR ROTARV SPIN WOOL GLASS
FIBER MANUFACTURING3
EMISSION FACTOR RATING: B
Particulate Organic compounds
Products f
R-19
R-ll
Ductboa-d
Heavy
densiry
'ront half
17.81
(36.21)
19.61
(39.21)
27.72
(55.42)
4.91
(9.81)
Back half
4.25
(8.52)
3.19
(6.37)
8.55
(17.08)
1.16
(2.33)
Total
22.36
(44.7?)
22.79
(45.59:
36.25
(72.50)
6.07
(12.14)
Phenolics
3.21
(6.92)
6.21
(12.41)
10.66
(21.31)
0.88
(1.74)
Phenol I
0.96
(1-92)
0.92
H.«4)
3.8'«
[7. 68)
0.53
(1.04)
rormaldehyde
0.75
(1.50)
1.23
(2.46)
1.80
(3.61)
0.43
(0.85)
""Reference 4. Expressed in kg/Mg (Ib/ton) of finished product. Gas stream
did not pass through any added primary control device (wet ESP, ventuti
.scrubber, etc.)-
Included in total particular catch. Ihpsp organics are collected as. con-
deusible parMcuiate matter and do not necessarily represent the entire
organics present in the exhaust ^as stream.
Induces phenol.
References for Section 8.11
1. J. R. Schorr, e t a_l. , Source Assessment: Pressed and Blown Glass
Manufacturing Plants^, EPA-600/2-77-005, U. S. Environmental Protection
Agency, Research Triangle Park, NC, Janjary 1577.
Mineral Products Industry 8.11-9
-------
2. Annual Book of ASTM Standards, Part 18, ASTM Standard C167-64
(Reapprovt'd 1379), American Society for Testing and Materials,
Phi^adephia, Pa.
3 . Standard of Performance Foi Wn ol Fiberglass Insula ti_on Manufact uring
Plants, 50 FR 7700, February , 1985.
4. Wool Fiber 'jl^ss Insul^tion_Mani!fa[:turing Industry.
_
I_n format ion for Proposed Standards. L . S. Environmental ProtL-ctioci
Agency, Pest-arch Triangle Park, NC , EPA- 450/3- 83-022a , December 1983.
B.11-10 KHISS ION FACTORS 'J/BS
-------
8.12 FRIT MANUFACTURING
8.12.1 Process D -scription1 -2
Frit is used in enameling iron and steel a^.d in gluing porcelain and poiter/. In n typical plant, ihc uw
materials consist of a combination of materials suci; as borax, feldspar, sodium fuoiudf or fluorspar sod? a^i
zinc oxide, litharge, silica, boric acid, and zircon. Frit is prepared Jiy fusing the>:-.- v^riouf minerals in '-* smelter.
and the mollen material is theii quenched with air or water This quenching opcrdtion causes tht Title ro solidify
rapid!; and shalter into numerous small glass, particles, culled frit. After a d;ying process, iU:. fr.i fs i:nely ground
(n a ball mill where other materials are addci
8.12.2 Emissions and Controls2
Significant dust and fume emissions are created by the fat-smelting operation. These emissions consist
primarily of condensed metallic oxide fumes liiat ha«j vaktilized from the niohfn harge. They aKr, contain
mineral dust carryover and sometimes hydrogen fluoride. Emissions can be reduced by not rotating tii« smelter
too rapidly (to prevent excessive d^st carry -over) and by not heating ihe batch too rapidly or loo !ciig(to prevent
volatilizing the more fusible elements).
The two moit feasible control devices for frit spellers me baghouses and ventun water scrubbers. En:i:sion
factors for frrt smelters are shovkii in Table 8.12-1, Collection efficiKn ,i?s obtainable for venturi scrubbers are ;Jso
shown in the table.
4/73 Mineral Products Jndustry 8.12-1
-------
Table 6.12-1, EMISSION FACTORS FOR FRIT SMELTERS
WITHOUT CONTROLS*
EMISSION FACTOR RATING: C
Type of furnace
Rctar /
Particulars'"
Ib'ton
16
kg/MT ]
8
Fluorides5
Ih/ton
-
kg/MT
25
aRelererce 2 Em ssion tac'.ors exp'es<«d as units p«r jnit we ghi of cha'ge.
A ventun srruliber'.vi'.h n 71 inch (536-mnni water-Qduge pressure du p can reduce oar-
licuidt» emissicns by £7 percent and Muor.des by 94 percent.
References for Section 8.1 2
I. Duprey, R L. Cumpitalicm of Aii Poliutant Emission Factors. U.S. DHL'W, PHS, National Ct.-r.ier for Aii
Pollution Control. Durham, N.C. PHS Piiblicalion Number W9-AP-41 ]%8. p. 3"-.18,
2, Spinks. J. L. Frit Smelters. In: Air Pollution Engineering Manual. Danielson. J. A. («^d.), U.S. DHEW.PHS.
National Center !'oi Air Pollution Control. Cincinnati, Ohio. PHS Publication Numbci 9t)0-AJ-'-40. 1967. p.
738-744.
8.12-2
EMISSION FACTORS
2/72
-------
8.13 GLASS MANUFACTURING
8.13.1 General >•»
Commercially produced glass can be classified as cither soda-lime, lead, fused silica, borosilicate, or 96
prri.-«-nt silica. Soda-lime glass, which constitutes 77 percent of total glass production, will be discussed in this
section. Soda-lime glass consists of sand, limestone, soda ash, and cutlet (nroken glass). The manufacture of glass
i an oe broken down intofuur phases: (1) preparation "f ra~* material, (2) melting in a furnace, (3) forming, and
(4) finishing. Figure 8.13-1 show* an overall flow diagram for glass manufacturing.
The pr> ducts of the glass manufacturing industry are flat glass, conuiner glass, or pressed and blown glass.
The pro,--ed;iri- for manufarluring glass is the same for all three categories except for forming and finishing. Flat
glase, which comprises 24 percent of total glas« production, is formed b> either the float, drawing, or rolling
proct s.i Container jjlas: and pressed and blown glass, whirh comprise 51 snd 25 percent, re' pectively, of total
glass prnrlurtion, utilize either pressing, blowing, or pressing and blowing to form the desired product.
As raw materials are received, they are crushed and stored in separate elevated bins. The riw materials a re
transferred through a gravity feed system to the weigher and mixer, where the material dnd cullet are mixed to
ensure linmogeueous melting. The mixture is then transferred by convey D: !o ihe batch storage bin where it
remains until being dropped into the furnace feeder, which supplies :he raw material to the meltinp furnace. All
equipment used in handling and preparing the raw material is housed separately from the furnace and is usually
referred iO as the batch plant. Figure 8.13-2 shows a flow diagram of a batch plant.
The furnace most commonly utilized is a continuous regenerative furnace capable of producing between 50
and 300 tons (45 and 272 meii ic tons) of glass per day. A furnace may have either side or end ports connecting
brick checkers to the inside ot the melter. The purpose of the checkers is to conserve fuel by utilizing the heat of
the combustion products in one side of the furnace to preheat combustion air in theother sid:. As material enters
the melting .''urnace through the feeder, it floats on the top of the mol'en glass already in the furnace. As it melts,
it passes lo the front of the nu iterand eventually flows through d throat connecting the melter and the refiner. In
the refiner, the molten glass is heat conditioned for Helivery to the forming process. Figures 8.13-3 and 8.13-4
show side-port and end-port regenerative furnaces.
HAW
MATERIAL
MELTING
FURNACE
GLASS
FORMING
ANNEALING
JjjCYCLE UNDESIRABLE
GLASS
PACKING
STORAGE
OR
SHIPPING
12/77
8.13-1. Flow Diagram for glass manufacturing.
Mineral Products Industry
F.13-1
-------
C J.I U
S;RC»
CC'.VETOR
813-2 Flew diagram of a batch plant
After refining, the molten glass leaves the furnace through forehearths (except for the float process in which
molt en glass goes directly 10 the tin hathj and goes to be shaped by either pressing, blowing, pressing and blowing,
drawing, rolling, or floating, depending upon the desired product. Pressing and blowing are preformed
mechanically using blank molds and glass cut into sections (gobs) by a set of .-hears. In the drawing process,
mult».n glass indrawn upward through rollers that guide the sheet pla*s. The thickness of thesheel is determined
by the speed of the draw and the ccnfiguralion of ihe draw bar. The rolling process is similar lo the drawing
process except thut the glass is drawn horizontally by plain or patterned rollers and, for plate glass, requires
grinding and polishing. The float process utilizes a molten tin bath over which the glass is drawn and formed in to a
finely f nishe<] surface requiring no grinding or polishing. The product undergoes finishing (decorating or
coating and annealing (removing unwaiueJ .-.iress areas in the glass), and is then inspected and prepared tor
shipment to market. A iy damaged or undersirable glass is transferred back K the batch plant to be used as cullcl.
3.13.2 Emissions and Controls1'3
Table 8.13-1 lists ccntrolled ,-nd uncontrolled emission far.tcrs for gUsf inanufarturmg.
The; main pollutant emitted by the batch plant is particulates in (before of dust. This can be con trolled, with
99 to 100 percent eflidi.vi(-y, by enclosing all possible dusl souues and ush: ; biiphoubes or cloth fillers. Another
way to control dust emissions, also with an efficiency ajipronching 100 percent, is to treat the batch to reduce ihi-
amount cf fine nartirles present. Forms of preparation are presintcring, hriqi;e!ting, pelletiiing, or liquid ilkali
treatment.
8.13-2
F MISSION FACTORS
12/77
-------
E. 13-3. Side-port continuous regenerative furnpce.'
IIH1» )IM II.1
51I1J SHIIICI tN til Nil
12/7'
8.13-4. End-port continuous regenerative furnace.1
MI>ERAL PRODUCTS INDUSTRY
8.1 .t-3
-------
TABLE 8.13-1. EMISSION FACTORS FOR GLASS MANUFACTURING11^
EMISSION FACTOR RATING: B
r/>
to
t—i
o
•z
Tl
§
O
W!
00
ro
Paniculate" Sulfur
Process
Raw njterldls handling^
(all types of glau) "eglf ">e«lf 0
Mrtal furnace**
Container
Uncontrolled 0.7 1.4 1.7
(fl.t-n.9) (0.9-1.9) (1.0-2.4)
W/low-*nergy scrubh«rh 0.4 0.7 rt.<»
W/venturl scrubber1 < P.I O.I O.I
K/onghouse) Negl Nejl 1.7
W/e]ertro-':!.ic r--"' t>i islor1 Negl Negl 1.7
Flat
Uncontrolled l.C 2.0 !.5
(0.4-1. A) (O.S-3.7) (1.1-1.*)
W/lov-energy sc.t>jbberh C.S i.O 0.9
W/venturl scrihoer1 Negl Negl 0.1
tf/baghousc* Negl 1*ttl i.S
U/elecrroBCarlr preclp! rator11 Nrnl Nag] 15
Pressed and nlnwn
'Jncontrolli»d 8.7 P. 4 2.H
(n.5-!2.«) (1.0-25.1) ("-5-5.4)
W/low— t»n«rgy scrubber 4.2 fl.4 1.3
W/venturl scrubber1 0.5 0.9 C.I
W/baghouse.! 0.1 0.2 2.R
(//electrostatic precj pi Catork 0.1 1.2 2. A
Fornlng and finishing
Contain*- '••• Negl Ne?i Negl
Flat Kegl Kyj-,1 Negl
total"'0'? -
"Eclssion factor! are express**** a* Vg/Nr (Ib/ton) of glass produced.
ranges are shown In parentheflac along vlth ;h<* average enl9«lon factor.
nF AL**m pr jducec* since b^tch prep&iutlon is the name tut all types. Par
fo^a of control (I.e. baghoupcs, scrubbers, o*1 centrlfu^ul colleclurs).
^Negllglbl' .
^Control efficfrncles for th« vnilqua devices are npplieii only to the
Approximately 52 percent efficient In reducing p^rticulace and flulfur
oxides uatlaslona. Fffect on nitrogen oxldeE Is unknown.
oxides
Ib/toa
0
3.4
0.2
3.4
3.4
3.0
(2.2-1.8)
1.5
0.2
3.0
3.0
5.6
1 1.1-10.9)
2.7
0.3
*•.',
5.6
Negl
-
Nitrogen elides Drgailca Carbon aonodd* La ad
KfVNg Ib/LOn kg/>f« IS/ten kg/>»j Ib/tmi kf/^sT Ib/ton
J 0 0000 - -
3.1 4.2 O.I 0.2 0.1 0.2
(l.*-4.5) (3.3-9.1) (0-0. J) (0-0.4) (0-0.2) (0-0.5)
3.1 6.2 o.l 0.2 0.1 0.2
3.1 «.2 O.I 0.2 0.1 0.2
3.1 «.2 n.l n.2 0.1 0.2
3.1 4.2 0.1 0.2 0.1 0.7
4-n 8.0 < o.i < o.i < o.i < o.i
(2.B-5.2) (5.6-10.4)
4.0 *.o < a.i < 1.1 < o.i < n.i
4.n e.o < o.i < o.i < o.i < o.i
4.0 «.J < o.i c o. i < o. i < o. ;
4.0 8.0 < O.I < 0,1 < 0.1 < 0. 1
•*-3 H.5 o.2 0.3 0.1 0.2
(0.4-10.0) (0. ",-211.0; «0. 1-0.3)(O.I-I.O) (O.I-" "iO.l-n.3J
2.2 8.5 0.2 (1.3 0.1 0.2
2-2 8.5 o.; o.3 O.I 0.2
2.2 8.5 0.2 0.3 O.I 0.2
Z-2 *-5 0.2 0.3 C.I 0.2
Nagl Nagl 4.4 8.7 Negl legl
Negl Negl Htg] ttagl Negl Htgl
Negl Negl 4.5 9.0 N«gl Negl
5 2.5
'Appropriately 95Z efficient la reducing partlculate and fulfur Olid*
enlaslona. Effect on nitrogen oilJes La unknown.
^Appio«lnat.ely 99 £ efficient In reducing p«-tlculice esrlcsloni.
Paniculate eailaslon factors arc calculated mirg data for furnacaa
netting soda line and lead Rlasies. No data are available for bora-
slllrare or opal n'ssaes.
'Rydroearton asdaalon factors for container aod preaaed and blown glass
eratloa, ab
-------
The uelting furnace contributes over 99 percent of the total emissions
from tha glass plant. In the furnace, both particulatee and gaseous pollutants
are emitted. Particulates resu't from volatilization of materials In the melt
that combine wich gases to form condenantes. Thesi; are either collected In the
checker-work and gas passages or escape to the acmoephere. Serious problems
arise when the checkers are not properly cleaned In that slag can form, clog-
ging the passages and eventually deteriorating the condition and efficiency
of the furnace. Nitrogen oxides form when nitrogen and oxygen react In the
high temperatures of the furnace. Sulfur oxides result from the decomposition
of the sulfates In the batch and the fuel, froper maintenance and firing of
the furnace can control emissions and also add to Lhe efficiency of the
furnace and reduce operational costs. Low-pressure wet centrifugal scrubbers
have been used to control particulatee and sulfur oxides, but their low
efficiency (approximately 50 percent) Indicates their .Inability to collect
pariiculates of subroicron size. High-energy venturi scrubbers are approx-
imately 95 percent effective in reducing particulate a.id sulfur oxide ^mis-
sions; their effect on nitrogen oxide emissions is unknown. Baghouses,
which have up to 9".- percent partlculate collection efficiency, have been
used on small regenerative furnaces, but due to fabric corrosion, require
careful temperature control, electrostatic prectpitatora have an efficiency
of up to 99 percent In the collection of participates.
Emissions from the forming and finishing phase depend upon the type of
glass being manufactured. For container, press, and blow machines, the major-
ity of emissions result fron the gob cooing Into contact with the machine
lubricant. Emissions in the form o£ a dense white cloud, which can exceed
40 percent opacity, are generated by flash vapor5zatlon of hydrocarbon greases
and oils. Grease and oil lubricants are being replaced by sllicone emulsions
and water-soiuole oils, which jay virtually eliminate the smoke. For flat
glass, the only contributor to air pollutant emissions Is gas combustion In
the annealing lehr, which la totally enclosed except for entry and exit
openings. Since emissions are small and operational procedures are efficient,
no controls are utilized.
References for Section 8.13
1. J. A. Danielson (ad.)., Air Pollution Engineering Manual (2nd Ed.), AP-40,
U.S. Environmental Protection Agency, Research Triangle Park, NC, 1973.
Out of Prlit.
2. Richard B. Reznik, Si urce Assessment; Flat Glass Manufacturing Plants,
EPA-600/20-76-032b, T". S. Environmental 'Projection Agency, Research Tri-
angle Park, NC, March 1976.
3. J. R- Schoor, D. T. Hoole, P. R. Stlcksel, and Clifford Brockway, Source
Assessment: Glass Container Manufacturing Plants, EPA-6CO/2-76-269, U.S.
Environmental Protection Agency, Washington, DC, October 1976.
12/81 Mineral Products Industry 8.13-5
-------
4. A. B. Tripler, Jr, and G. R. S'lltheon, Jr., A Review of Air Pollution Prob-
lems and Control In the Ceramic Industries, Battelle Memorial Institute,
Columbus, OH, presented at 72nd Annual Meeting of the American Cer.imlc
Society, May 1970.
5. J. R. Schorr, D. T. Hoole, M. C. Broctway, P. R. Stlcksel, rnd D. E. Nlesz,
Source Assessment: PressedandBlown Glass Manufacturing Plants, prepared
for U. S. Environmental Protection Agency, Research Triangle Park, NC,
Publication Number EPA-600/2-7/-005, January i977.
6. Control Techniques for Lead Air Emissions, EPA-450/2-77-012, U. S, Environ-
mental. Protecticn Agency, Research Triangle Park, NC, December 1977.
7. Confidential test data, PEDCo-Environmental Specialists, Inc., Cincinnati,
OH.
8.J.V6 EMISSION FACTORS 12/81
-------
8.14 GYPSUM MANVFACTURIHG
8.14.1 Process Description
Gypsum is calcium sulfatc dihydrate (CaSO • 2H70), a white or gray
naturally occurring mineral. Raw gypsum ore is processed into a variety of
products such as a Portland cement additive, soil conditional, industrial
and building plasters, and gypsum wallboard. To produce plasters or
wallboard, gypsum must first be partially dehydtared or cilcined to produce
calcium sulfate hemihydrate (CaSO • ^H^O), commonly called stucco.
A flow diagram for a typical gypsura process producing; both crude and
finished gypsum products is shown in Figure 8.14--1. In this process, gypsum
is crushed, dried, ground and calcined. Some of the operations shown in
Figure 8.14-1 are not performed at all gypsum plants. Somu plants produce
only wallboard, and many plants do not produce soil conditioner.
Gypsum ore, from quarries and/or underground mines, is crushed and
stockpiled near a plant. As needed, the stockpiled ore is further crushed
and screened to about 50 millimeters (2 inches) in diameter. If the
moisture content of the mined ore is greater than about 0.5 weight percent,
the ore must, be dried in a rotary dryer or a heated roller mill. Ore dried
in a rotary dryer is conveyed to a roller mill where it is ground to
90 percent less 149 micrometers (100 mesh). The ground gyp:;ura exits the
mill in a gas stream and is collected in a product cyclone. Ore is
sometimes dried in the roller nill by heating the gas strean, sc that drying
and grinding are accomplished simultaneously and no rotiry dryer is needed.
The finely ground gypsum ore is known as landplaster, which may be used as
soil conditioner.
In most plants, landplaster is fed r.o kettle calciners or flash
calciners, where it Is heated to remove three quarters of the chemically
bound water to form stucco. Calcination occurs at approximately 120 to
150°C (250 to jOl^F), and 0.908 megagrams (Mg) (one ton) of gypsum calcinus
r.o about 0.77 Mg (0.85 ton) of stucco.
In kettle calciners, the gypsum is indirectly heated by hot combustion
gas passed through flues in the kettle, and the stucco prod\ rt is discharged
irr,:,> n "hot pit" located below thu kettle. Kettle calciners may be operated
in either batch or continuous modes. Tn flash caTciners, the gypsum Is
r.irecfjy contacted with hot gases, and the stucco product is collected at
the bottom of the calclner. A major gypsum manufacturer holds a patent on
the design, of the flaa1" caiij.'ner.
At some gypsum plants, drying, grinding and r.alclning are performer 1n
heated impact mills. In these mills, hot gaa contacts gypsum as it is
ground. ThE gas dries and calcines the ore and then convey.'! the stucco to a
product cyclone for collection. The use cf heated impact mills eliminates
the need for lolary dryers, calciners and roller -nil IP.
5/83
Minerjl Products Industry 8.14-1
-------
o
is
Tl
>
n
H
O
Itr t»
!. rt\n uorct
7. tntontlol «1ll1on«
J. r«9
-------
Gypsum and stucco usually are transferred from one process to anothei
in screw conveyors or bucket elevators. Storage bins or silos are normally
located downstream tf roller mills and calciners but may also be u?rd
elsewhere.
In the manufacture of plasters, stucco i3 ground further in a tube or
ball mill and then batch mixed with rctarders and stabilizers to produc*
plasters with specific setting rates. The thoroughly mixed plaster is fed
continuously from IntermediatR storage bins to a bagging operation.
In the -ianufacture of wallboard, stucco fr
-------
TABLE 8.14-1. PARTICULATE EMISSION FACTORS FOR GYPSUM PROCESSING*
EMISSION FACTOR RATING: B
Pro*1*!* Uocoitcollcd
kg/Mg Ib/ton
Crutriera, screens,
atoekpllea, road* d d
Rotary arc dryera*'''8 O.OO^'.FTF)1' /? 0. 1* '5FF> 1 1?7
Hollar Dills1 1.3J Z,b!
.Inpaer nil'.B1'1 508>) !COBlJ
Flalh c*lclners*'n 19 "J7
Continuous kettle
cilclnen" 21P 41P
Ylth
fabric
fllt!rc
kg/Hg Ib'ton
.
D.02h 0.04h
0,06 0.12
o.oi o.o;
0.02 0.0'-
0.003P 0.006P
With
alectroetatlc
prtcipttator
kj/Hg Ib/con
..
SA
0,05k 0.09k
RA
NA
0.05^ T.093
lb/300 ft
kg/106 o2 lb/10* ft2
Board end sawing
2.4 en
3.7 B
(B (O board*
(12 ft) board*
0.0^
0.03
u.8
0.5
36
36
7.5
7.5
*Baitd on proctu output production ratt. Racing ipplle« to all factors «xc«pc vhare ottttrviaa natcd.
Daih - not ippllcablt. HA - not avallibla
Factoti rcpi-cianc irv tv*t anterlng the tmlsslon cortrol device.
cn«f«ronc«« 3-*> 8-11. Fuctori for sources concrolltt. vtth fabric flltara are bai«d on fjl»e jat fabric
filter* ul'ch actual ntr/cloth ratio* ringing from 2.3:1 - 7.0:1, aechanlcal ahakar fabr'.c fKttra vlth
racloa frco 1.5:1 - t.6.1. ar.d t reverse flow fabric filter with a ratio of 2.3:1.
Factors foi thaaa opartkClona an In lactlooa S.19 and 11.2.
Includes paniculate matter from fuel conbuetlon.
Refererces 3-4, 8, 11*12. Equation IE for emission rate upatrean of anv procee* cyclonea and £*
applicable cnl Co crjncurranl rotaiy oie dryers vlch flowrc:es of 7.5 n It (16,000 acfa) or Id*.
ITr In Che uncontrolled emission factor aquation Is "flov feed factor", the ratlc of ga* maaa
cac« p«r unit dryer croai aacclonai area Co the dry na*8 f:ed rat*. In the following units:
•> 2
kit/hr - m of ga« flaw Ibi'hr - tt of gaa flow
Mg/hr dry feed tun/hr dry feisd
Manured uncontrolled emission Cactcra for 4.2 and ',' i fa (9000 and 12,000 acfdO rang* fron 5 -
60 Vg/M| (10 - '20 It/ton).
8niISSTOK FACTOF, RATING: C.
Applicable co rotary dryers with ind without process cyclones upacrean of Che fabric filler.
'Rpfi>rpn?et ll-'.i- Factors applv to both hec:ed and unheared roller 3111s.
Jyactnra repiesent emlstloni dovr.at ream of the product cyclone.
Factor is fpr combined emlisloi.s fron roller nilli and lce:rle calclnen, baaed on the Sura of .he roller
alii and kettle calclner ouipi •jroducLinn rates.
nefer'ncei 9, 11. As tiaed here, an Impact trill is A {irocnga unit with process cycl^.ieu and la
ua*d to di/. grind tid calcine gypaua ilnultaneons'y.
"References 3, 6, 1C. A flaih calclnei Ir a proctii unit uaed to cti:lna gypaum through direct contact
with hot gas. No grlndii:*, Is perfonaed in thH vinlt.
"Reference* 4-5, 11, 13-1*.
''Baled on emissions from both ;h< kettle
-------
TABLE 8.14-2. UNCONTROLLED PARTICLE SIZE DATA
FOR GYPSUM PROCESSING
Process Weight Percent
10 urn 2 un
Rotary ore dryer , ,
with cyclones 45 12
without cyclones 8 1
Continuous kettle calciners 63 17
Flash calciners£ 38b 10b
a
.Reference 4.
Aerodynanic diameter, Andersen analysis.
.Reference 3.
References 4-5.
f*
"Equivalent diaaeter, Cahco and Sedlgraph analyses.
XeferencesB, 6.
TABLE 8.14-3. PARTICLE SIZE DATA FOR GYPSUM PROCESSING
OPERATIONS CONTROLLED WITH FABRIC FILTERS
Process
Rotary ore dryer.
with cyclonea .
without cyclones
Flash calclners
Board end sawing6
Weight Percent
10 urn 2 vim
c 9
26 9
84 52
76 49
.Aerodynamic diameters, Anderaen analysis.
Reference 4.
Q
.Not available
Reference 3.
^References 3, 6.
References 4-5.
5/83 Mineral Products Industry 8.14-5
-------
Emissions from some gypsum sources are also controlled with
electrostatic precipitators (Ebr1). These sources Include rotary o-e dryers,
roller mills, kettle cnlciners and conveying systems. Although rotary ore
dryers may be controlled separately, emissions from -oiler mills and
conveying systems are usually controlled Jointly with keltle calclner
emissions. Moisture in the kettle calciner exit gas improves the ESP
performance by lowering the resistivity of th° dust.
Other sources of particulate em.'ssious in gypsum plants are primary and
secondary crushers, screens, stockpiles and roads. If quarrying Is part of
the mining operation, partlculate emissions may also result from drilling
and blasting. Emission factors for some of these sources are presented in
Sections 3.19 and 11.2.
Caseous emissions from gypsum proctsses result from fuel combustion and
may include nitrogen oxides, carbon monoxide and sulfur oxides. Processes
using fuel include rotary ore dryers, heited roller mills, impact mills,
calciners and board drying kilns. Although some plants use residual fuel
oil, Che majority of Lhe industry uses clean fuels such as natural gas or
distillate fuel oil. Emissions from fuel combust inn may be estimated
using emission factors presented in Sections 1.3 and 1.4.
References for Section t'.M
1. Kirk-Othmer Encyclopedia ofChemical Technology, Volume 4, John Wiley &
Sons, Inc., New York, 19n8.
2. Gypsum Industry - Background In formation^ tor Proposed Standards
(Draft), U. S. Environmental Protection Agancy, Research Triangle Park,
NC. April 198l.
3. Source Emissions Test Rcrport,Gold. Bond Building Products, EMB-80-
GYP-1, U. S. Envirorime.nl al Protection Agency, Research Triangle Park,
NC, November 1980.
4. Spurc.; Eml.ssj.ons Test Report, United States Gyjjpuni Company, EMB-80 -
GYP-?, U. S. EnvironmentalProtection Agency, Research Triangle Park,
NC, November 1980.
5. Source Emission Tests, United States Gypsum Company Wallboard Plant,
EMB-80-GYP-6, (J. S. Environmental Prct2ction Agency, Research Triangle
Park, NC, January 1981.
6. Source Emission Tests, Gold frond Building Products, EMB-80-GYP-5. U. S.
Environmental Protection Agency, Research Triangle Park, NC,
December 1080.
7. S. Oi'lesby ,-ind G. B. Nichols, A Manual of Electrostatic. Precipitation
Technology. Part II: Appllcation Areas, APTD-0611, U. S. Envlronmental
Protection Aj^ncy, Cincinnati, OH, August 25, 1970.
8. Official Air Pollution Emission Tests Conducted on the Rock Dryer
and /<3 Calcidyne Unit, Gold Bond BuilJing Products, Report No. 5767,
Rosnage' and .srsociates, Medford, NJ, August 3, 1979.
fl.14-6 EMISSION FACTORS V83
-------
9. Particulate Analysis of Gaicinator Exhaust at Western Gypsum Company,
Kramer, Callahan and Associates, Rosario, NM, April 1979. Unpublished.
10. Official Air Pollution Tests Conc'iicted on the #1 Calcidyner Baghouse
Exhaust at the Nntlonaj. Gypsum Co-.ppany, Report No. 2966- Rossna3el and
Associates, Atlanta, GA, April 10, 1978.
^1• Report to United States Gypsum Company on Partlculate Emission
Compliance Testing, Environmental Instrument Systems, Inc., Sou'.h
Bend, IN, November 1975. Unpublished.
12. Particulfete. Emission Sampling and Analyris^ Uiicod Stctgs Gyprum
Company, Environmental Instrument Systeins. Inc., South Bend, IN,
July 1973. Unpublished.
13. Written communication from Wyoming Air Quality Division, Cheyen.ie, WY,
to Michael Palazzolo, Radian Corporation, Durham, NC, 1980.
14. Written communication from V. J. Tretter, Georgia-Pacific Corporation,
Atlanta, GA, to M. E. Kelly, Radian Corporation, Durham, t!1,
November 14, 1979.
15, Telephone communication between Mic'imel Palazzolo, Radiai; Corporation,
Durham, NC, and D, Louis, C. E. Raymond Company, Chicago, IL, April 23,
1981.
16. Written communication from Michael Pal^zzolo, Radian Corporation,
Durham, NC, to B. L. Jackson> Weston Consultants, West Chest-er, PA,
June 19,
1980.
17. Telephone communication between P. J. Murin, RaHian Corporation,
Durham, NC, and J. W. Pressler, U. S. Department of thu Interior,
Bureau of Mines, Urshingtcm, DC, November 6, 1979.
5/33
Mineral Products fndiiRti / 3.14-7
-------
8.15 LIME MANUFACTURING
8.15.1 General1*
Lime is the high-tempera!-ire produrt of the caku.atiun of limestone. There are two kinds of lime:
high-talcium lime (CaO) and dolomitic lime (CaO • MgO». Lime U manufactured in various kinds of
kilna by one of the following reactions:
CaCOi i heat -• CO; + C«O (high lukium lime)
CV;Oi MgCXJ, * h..-at * Uh * CnO . MgO (dulumitic lime;
In some lime pUnts, the resulting lime is reacted (slaked) witli water to form hydrat»d lime.
The basic processes in the production of lime are (1) quarrying the raw limestone, (2) preparing the
limestone fortue 'tiln? by -ushing and sizing (3) caicining the limestone, (4) processing the quicklime
further by hydrating, and (3) miscellaneous transfer, storage, and handling operations A pent-ratizcd
material flow diagram for a lime manufacturing plant is given in Figure 8.15-1. Note that some of the
operations shown may not bi> performed in all plants.
The heart of a lime plant in the kiln. The most prevalent type of kiln in the ro'ary kiln, accounting
for about 90 percent of all lime production in the Uuictd States. This kiln is a long, cylindrical, slightly
inclined, refractory-lined furnace through which the limestone and hot • ombustion gates pass count-
ercurrently. Coal, oil, and natural gas may all be fired in rotary kilns. Product coolers and kiln-feed
preheateru of various types are commonly employed to recover heat from the not lime product ant!
and hot exhiust gases respectively.
The next most prevalent type of kiln in the United States is the vertical, or shu't, kiln. This kiln can
be described as an upright heavy a;eel ivlinrler lined with refractory material. The limestone is
charged at the top and calcined a? it descends slowly to the bottom of the kiln where it is discharged. ^\
primary advantage of vertical kilns over rotary kilns is the higher average fuel efficiency. The primary
disadvantages of vertical kilns are their relatively low production rates and the fait that coal cannot
be used without degrading the quality of I he lime produced. Although still prevalent in Europe, there
hav,-! b<-.e.n few recent vertical kiln installation!: 1.1 the United S'.ates because of the high production
requirements of domestic manufacturers.
Other, much less common, kiln types include rotary hearth and f!uidized-bed !;ilns The rotary
hearth kiln, or "calcima tic" kiln, is a circular-shaped kiln with asiowiy revolving donut-shftptd hearth.
In fluidized-bcd kilns, finely divided limestone is brought into direct contact with hot combustion
air in a turbulent zone, usually above a perforated grate. Dust collection equipmc ;t mus. be installed
on fluidized- bed kilns for process economics because of the high lime carryover into thcexhaust gases.
IJoth kiln types can achieve hiph production rates, biu neither can operai" with coal.
About 10 percent of ill lime produced is converted to hvdrateil
-------
LHMf STONE
OUARRV/MIIIE
3SS
SECONDARY
CRUSHER
SCREENS AND
CLASSIFIERS
K/Xr>/^
CONTROL
DEVICE
STONE
PREHEATER
FUEL
CONTROL
DEVICE
WATER
HVDPATOR
HVQRATED
LIME
LIMESTONE
KILN
(LIME
PRODUCT
COULER
LIME
KILN
EXHAUST
LJ
^STORAGE/
SHIPMENT
WATER SPRAY/
H»:T SCRUBBER
WATER/OUST SLURRY
MILL/AIR
^EPAIATOR
STORAGE/
SHIPMFNT
•^WN/'\A/
STONE
POTENTIAL
EMITTING POINTS
AIR/EXHAUST
8.15-1. Generalized lime manufacturing plant.
8.15-2
EMISSIOJN FACTORS
4/7',
-------
In the United State*, t he major use rf lime IB in chemical and metallurgical applications. Two of the
largest ua«a in theac areas ore M iteel flux and in alkali production. Other lesser user include con-
struction, refractory, and agricultural application*.
8.15,2 Emiasions and Controls'-5
Potential air pollutant emitting points in lime manufacturing plants are shown in Figure 8.15-1.
Par tii ulale i* the only pollutant of concerr. from moat of the operations; however, gaseous pollutants
are also emitted from kilns.
The largest source or particulate IB th: kiln. Of the various kiln type> in uie, fluidized-bed kilni
have the highee' uncontrolled particulate emissions. Thi» it due primarily to the very small feed rise
combined with the high air flow through these kiln«. Fluidized-bed kilns are well controlled for
maximum product recovery. The rotary kiln i« second to the flupdized-ried kiln in uncontrolled
pjrticulate emissions. This is attributed to the small feed size and relatively high air velocities and
dust entrainment caused by the rotating chamber. The rotary hearth, or "calcima«icr kiln rauks third
in dust production, primarily because of the larger feed si«e combined with tue fact that the limeitone
remains in a stationary position relative to the hearth during calcination. The vertical kiln has the
lowest uncontrolled dust emisaiom due to the large lump-siae fee J and the relatively slow air velocities
and ilow movement of material thro-igh the kiln.
Some sort of particulate control is generally employed on most kilns. Rudimentary fallout chamb-
ers and cyclone separators are commonly used for control of the larger particles: fabric and gravel bed
filters, wet (commonly ventur) scubbers, and electrostatic precipitatoia are employed for secondary
control. Table H.1S-1 yields approximate efficiencies of etch type of control on the various ;ypei i '
Nitrogen oxides, carbon monoxide, and i jlfur oxides arc all produce J in kilns, although the latter
are the only ge^eous pollutant emitted in significant quantities. Not all of the sulfur in the kiln fuel is
emitted as sulfur oxides because some fraction reacts with the materials in the kiln. Some sulfur oxide
reduction is also effected by th^ various equipment used for secondary particulate control. Estimates
of the quantities ut sulfur oxidus emitted from kilns, both before and after controls, are presented in
Table 8.15-1.
Hydrator em'ssions are low because water sprays or wet scrubbers are ,- lally installed foreconon.
ic reasons to prevent product loss in the exhaust gases, Emissions from pressure hyd.atora may hi'.
higher than f'om the nioie common atmospheric hydrators because the exnaust gasca arr released
intiTmillt'Ml l\ i» <-r ^hor' linir ),iliT» ,il>. rnjl.iii';(iM 'i-i ! riiiirf ill II iciill.
Product coolers are emission sources only when »ome of their exhaust gases are not recycled
through the kiln Tor use as combustion air. The trend M away from the venting of product cooler ex-
haust, hovever, to maximize fuel use efficiencies Cytionee, haghouses, and wet scrubbers have been
employed on coolers for particulate control.
Other particulate sources in limr plants include primary and secondary crushers, mills, &creer>»,
mechanical and pneumatic transfer operations, storage piles, and unpaved roads. If quarrying is a part
of the lime plant operation, particulate may also reuult frcni drilling and blasting. Emission factors
for so.nc of these operations ire presented in Section* 8.20 and il.2.
Emineion faotors for lime manufacturing are presented in Table S.1S-1.
4/77 Mineral Products Industry 8.15-3
-------
Tablt 8.15-1. EMISSION FACTORS FOR LIME MANUFACTURING
EMISSION FACTOR RATING. B
L
i"
: Partici
Source ; Ib/ton
Crushers, icreens, b
conveyo-i, storage
piles, unp.'vtd reads
Rotarv kilns
Uncontrolled0 340
After settling chamber
or loiye d.aineter 200
cyclone
Afler multiple cyclones ; 85e
After secondary dust
cnllectionf 1
Vertical kilns
Uncon'rol'ed '• 8
Calcimaiic kilns' ,
Uncontrolled 50
AtT.fr multiple cyclones 6
Afte< secondary dust
collection) NA
Fluidized-bed kilns NAk
Product coo^erc
UnConfLi.iBd 401
Hvd'diors ! 01m
Emissions3
jijtt Sulfji dioxide
ki-MT Ib/ion kg/MT
L Neg. Neg
170 : d id
100 id ; tl
43« ; d Id
05 g i g
4 • MAh | NAn
I
25 NA ! NA
3 NA i NA
1
NA NA 1 NA
NAk NA i NA
201 Neg. | Neq.
i
0.05m Neg. Neg.
Nitrogen oxides
Ib/ton
Neg.
kg/MT
Nag.
3 1.5
3 1.5
3
3
NA
0.2
o.:
0.2
HA
Neg
Neg.
1.5
1.5
NA
Carbon monoxi le
Ib/lor-
kg/rVT
Neg. Nee.
i
i
1
2
2
2
2
NA
i
0.1 NA
M
NA
1
1
1
1
NA
NA
NA
1
0.1 NA
NA
Neg
NA
Neg.
Nag. : Neg.
NA
NA
Neg.
Neg.
aA'l •mission ttcio'5 fo' * ins and cooierj a?.; Der Um. o' lime pr-.dfced. Divide by two 10 obtain factors pe- urni o* i-mestone 'eed to the km.
Factofi foi hydratori are p«> unit of hydrated Mme produced Vu'tiply jy 1.75 to obiam tjciors oer unit of nme feed to the T, nr.itor. All
emiiiioni data ar& ha ed on R«f»'enc8« 4 through G
bEm.ssion fdctorj fur thew ow^anons die prase nt»d in S*ruon6 8.20 ana 1 1 .2
cr\Jo MrTrtD'at* cnntroi except *or seultng tnat may fX jr n thL srack hrpprhmg andrKr..** 0,1**.-.
^VihKn iow-sul'uf ileis Ihan 1 per cent, Dy wfiighl) (L«O i d'C us*d, only ^buut 10 Dercfint of [hfe fu ma ie>y 53 percen> of The 'uel tu,1ur <$ * mil ted as SO-i
*Th,s *jcior thouio be used uvtiun cuji ^ fired m the kiln Limned data suggest that when only natural pas Or OH .t firf^j Ddrt'Culate
emissions jfier multiple cyclor>es .nay be di low ds 20 10 30 Ib/tcn i 10 to 1 b hj/MTS.
f Fabnc or grav«i bed *>it»rs, efccit -ostatu* p-ccipitators, or w«? (moi> common ty vpniun) scrubt«r;, Har liculate ronce ^tra'.ioni as lo*> as
0 2 Ih/'tfjn !0.1 Vy/M"T ) HJVC hp1!B''i and -en*u" scrubbers Hflv* been crnptoyea on cJ Cimatic kilni ;No data a^e available on pa'TCLiate trnisjions a**.e^
iecon/1«'v cannol.
Fl jidiiwd irtd «i n;, must employ sophist caieO clu&i c j! lectio •< equipmeni tut pujurts economics: hence, pacula!e ftmuiioni wiM
rleu1 'I c,n the atficiencv of !he Lonfro! nrjuipmen! tnftallea.
'Some or ol! of th* coolf1' e*h iusf u l
. not ffcvc'ttj iu Ihe kiln
J in !he kiln -" thai
"M n,« i? ^ tvDicji pa- itcUdle luarJinq *or a!mo«^h» :c lyrJ atn^s 'ollorttng water sprays or w*t scrubber*. L'rniteH JJ-.M
parricuidiu emissions if ^m pri-k.ufi; hv'oreto'i nia; hy ^riprc»irnate y 2 ib/inn (1 kq/MTJ cf hydfaie prodtrcd, a**pr
8.15-4
EMISSION FACTORS
4/77
-------
Reference* for Section 8.15
1. Lewi*, C.J. and B.B, Crocker. The Lime Industry's Problem of Airborne Duit. J. Air Pol. Control
AMO. Vol. 19, No. 1. January 1969.
2. Kirk-Othmer Encyclopedia of Chemical Technology. 2nd Ed. Vol 12. New York, John Wiley and
Sons. 1967. p. 414-459.
3. Screening Study for EmiMioni Characterization From Lime Manufacture. Vulcan-Cincinnati.
Cincinnati, Ohio. Prepared for U.S. Environmental Protection Agency. Reiearch Triangle Park,
N.C. Under Contract No. 68-02-0299 August 1974.
4. .Evans, L.B. et al. An Investigation of the Beit Systems of Emission Reduction For Rotary Kilns
and Lime Hydratori in the Lime Industry. Standards Support and Environmental Impact
Statement. Office of Air Quality Planning and Standards. US. Environmental Protection
Agency. Research Triangle Park, N.C February 1976.
£. Sourci Test Data on Lime Plants from Office of Air Quality Planning and Standards. U.S.
Environmental Protection Agency. Research Triangle Park, N.C. 1976,
6. Air Polluta t Emifsion Factors. TRW Systems Group. Helton. Virginia. Prepared for the
National Air Pollution Control Administration, U.S. Department of Health, Education, and
Welfare. Washing
-------
8.16 MINERAL WOOL MANUFACTURING
8.16.1 Process Description
1.2
The product mineral wool used to be divided inlo three categories slag wool, rock wool, and glass wool.
Today, however, straight slag wool and rock wool as such are no longer manufactured. A combination of slag and
rock constitutes the charge material that now yields a product ctav.ified as a mineral wool, used mainly for
thermal and acoustical insulation.
Mineral wool is made primarily in cupoh' furnaces charged with blast-furnace i.Jag, silic:i rock, and coke. The
charge is heated to a molten state at about 3000°F (I650°C) and then fed to a blow jhamber. where steam
atomizes the molten rock into globules that develop long fibrous tails as they are drawn to the other end of the
chamber. The woo) blanket formed is next conveyed to an oven to cure the binding agent and then >o 3 cooler.
8.16.2 Emissions and Controls
The major source of emissions is the cupola or furnace stack. Its discharge consists primarily of condensed
fumes that have volatilized from the molten charge and gases such as sulfur oxides and fluorides. Minor sources of
paniculate emissions include the blnwchamber. curing oven, and cooler. Emission factors for various stages ot
mineral wool processing are shown in Table 8.16-1, The effect of control devices on emissions is shown in
footnotes to the table.
2/72 Mineral Products Industry 8.16-1
-------
8.16-1. EMISSION FACTORS FOR MINERAL WOOL PROCESSING
WITHOUT CONTROLS"
EMISSION FACTOR RATING: C
Type of process
Ci-pola
Reverheratory furnace
Blow chamber0
Curing ovdnd
Cooler
Participates
Ib/ton
22
5
17
4
2
kg/MT
i:
Sulfur oxides
Ib/ton
0.02
2.5 ; Neg41
8.5
2
1
Neg
|\i=r
Neg
kg/MT
0.01
Neg
Neg
Neg
Neg
"Reference 2. Emission factors expressed it units per unit weight of charge.
"Negligible.
CA etmtnlugal water scrubtoarcon reduce pa'tn-ulate emissions by 60 .jercent
dA direci-Hame afterburner can ruduce paniculate omissions b/ 50 percent.
References Cor Section 8.16
1. Duprey, R. L. Compilation of Air Polluf t Emission Faclors. U.S. DHEW, PHS, National Center for Air
Pollution Cuntrol. Durham, N. C. PHS Publication Number 999-AP-42. 196S p. 39^0.
2. Spinks, I. L. Mineral Wool Furnaces. In: Air Pollution Engineering Manual. Daniebon, J. A. (ed.). U.S.
DHF.W, I'HS, National Center for Air Pollution Control. Cincinnjii, Ohio. PHS Publication Number
999-AP-40. 1967. p. 343-347.
8.16-2
EMISSION FACTORS
2/72
-------
8.17 PERLITE MANUFACTURING
8.17.1 Process Description1 -2
Fertile is a glassy volcanic rock consisting of oxides of silicon and aluminum combined as a natural glass by
water of hydration. By i process called exfoliation, the material is rapidly heated to release waler of hydiaticm
anu thus to expand the spherules into low-density particles used primarily as aggregate in plaster and concrete. A
plant for the expansion of perlite consist;; of ore unloadhg and storage facilitit... a furnace-feeding device, an
expanding furnace, provisions for gas and piodua cooling, and product-classifying and p-oduct-collecling
equipment. Vertical furnaces, horizontal stationary furnaces, and horizontal rolaiy furnacss ire used foi the
exfoliation of pcrlitc. although the vertical types are the most numerous. Cyclone sepaiators a>c used to colled
the product.
8.17.2 Emissions and Controls2
A fire dust is emitted from the outlet of rhe last i:ioJuct collector in a perlne expansion plant. The fineness of
the dust vanes, from one plant to another, depending upon the desired product. In order to achieve complete
control of these particula'e emissions, a baghouse is needed. Simple cyclones and sniiiii multiple cyclones are not
adequate loi collecting the fine dust from perlite furnaces. Table 8.17-1 summarizes the emissions from perlite
manufacturing.
Table8,17 1. PARTICULATE EMISSION FACTORS
FOH P-RLITE EXPANSION FURNACES
WITHOUT CONTROLS"
EMISSION FACTOR RATING: C
Type of furnace
Verticfc'
Emissions^
Ib/ton
21
kg/MT
1
10.5
cr 3 Emission factors expressed as i.mts per unit we i grit of
criars;t .
"Primary cyclone) will collect 80 percent c< the paniculate: above
20 micrometers, and twghouws will collect 96 percent cl the particles
above 20 micrometers."
2/72 Mineral Products Industry 8.17-1
-------
References for Section 8.1 7
1. Duprey, R. L. Compilation of Air Pollutani Emission Factoiv U.S. DlltW. tHS, National Ccrler for Air
Pollution Control. Duihani, N.C. PHS Publication Number 999-AP-4:. 1968. p. 39.
2. Vincent, E. J. Pi:rlile*ExpandJng Furnaces. In: AirPo'lulion Engineering Manual. Danielson.J A. (ed.). U.S.
DHEW. PHS, National Center for Air Pollution Control. Cincinnati. Ohu>. ^HS Pnblicai on Number
999-AP-40. 196". p. 350-352.
3. Unpublished data on perlite expansion furnace. National Center for Air Pollution Control ( nuinnati, Ohio.
July 1967.
8.17-2 EMISSION FACTORS 2/72
-------
3.18 PHOSPHATE ROCK PROCESSING
8.18.1 General
The processing of phosphate rock for use in fertilizer manufacture
consists of benefioiation, drying or calcining, and grinding stages.
Sini_e the primary use of phosphate rock is in the manufacture of phos-
phatic fertilizer, only those phosphate rock processing operations
associated with fertilizer manufacture are discussed here. A flow
diagram of these operations is shown in Figure 8.18-1.
Phosphate rock from the mines is first sent to beneficiation units
to remove impurities. Steps used in beneficiation depend on the type of
rork. A typical Lsueficiation unit for processing phosphate rock mined
in Florida (about 78 percent of United States plant capacity in 1978)
begins with wet screening to separate pebble rock (smaller than 1/4 inch
and larger than 14 mesh) from the balance of the rock. The pebble rock
is sent to the rock dryer, and the fraction smaller than 14 mesh is
slurried and treated by two-stage flotation. The flotation process uses
hydrophilic or hydrophobia chemical reagents with aeration to separate
suspended particles. Phosphate rock mined in North Carolina (about 8
percent of United States capacity in 1978) does not contain psbble rock.
In processing this type of phosphate, the fraction larger than 1/4 inch
is sent to a hammer mill and then recycled to the screens, and the
fraction less than 14 mesh is created by two-stage floatlon, like
Florida rock. The sequence of benefIciation steps at plants processing
Western hard phosphate rock (about 10 percent of United States capacity
in 1978) typically includes crushing, classification and filtration.
Th« size reduction is carried out in several steps, the last of which is
a slurry giinding process using a wet rod mill to reduce the TOCK to
particles about the size of beach sand. The slurry Is then classified
by size in hydroclones to separate tailings (clay and particles smaller
than about 100 mesh), and the rock is then filtered from the slarry.
Beneficiated rock is commonly stored in open wet piles. It is reclaimed
froa these piles jy one of several methods (Including skip loaders,
underground conveyor Vj.lts, and aboveground reclaim trolleys) and IE
then Conveyed to the next processing step.
The wet ber.eficiated phosphate rock Is then dried or calcir.ed,
depending on its organic content. Florida rock is relatively free of
organics and is dried in direct fired dryers at about 250eF (120°C),
where the moisturp content of the rock falls from 10-15 percent to 1-3
percept. Both rotary and fluidized bed dryers are used, but rotary
dryers are more common. Most dryers are fired with natural gas or fuel
oil (No. 2 or No. 6), with many equipped to burn more than one cype of
fuel. Unliks Florida rock, phosphate rock mined from other reserves
contains organics and must be heated to 3400° - 1600°F (760°C - 870CC)
to remove them. Fluidized bed calciners are most coinmc.-.ly used for this
purpose, but rotary calciners are also used. After drying, the rock is
usually conveyed to storage silos on weather protected conveyors and,
from there, to grinding mil]9.
2/80 Mini-nil l»rniliii-l.« liHliiHri H.IH-I
-------
Table 8.18-1. UNCONTROLLED PARTICULATE EMISSION FACTORS
FOR PHOSPHATE ROCK PROCESSING3
EMISSION FACTOR RATING: B
Emissions
Type of Source Ib/ton
Drying 5.7
(1.4 - 14.0)
Calciningb 15.4
(3.8 - 38.0)
h
Grinding 1.5
(0.4 - 4.0)
Transfer ind storage0 2
Open storage piles 40
kg/MT
2.9
(0.7 - 7.0)
7.7
(1.9 - 19.0)
O.S
(0.2 - 2.0)
1
20
Emission factors expressed as units per unit weight of processed
phosphate rock. Ranges in parentheses.
Reference 1.
^Reference 3.
Reference 4.
Dried or calcined rock is grmmd in roll or ball mills to a fine
powder, typically specified as 60 percent by weight passing a 200 roesh
sieve. Rock is fed into the mill by a rotary valve, and ground rock is
swept from the mill by a circulating air stream. Product size classi-
fication is provided by "revolving whizzers" and ' y an air classifier.
Oversize particles 're recycled to the mill, and product size particles
ar«=> separated from the carrying air stream by a cyclone.
6.18.2 Emissions and Controls
The maj.>r emission sources for phosphate rock processing art
dryers, calciners and grinders. These sources emit particulates in the
^orm of fine rock dust. Emirsion factors for these sources ar'" pre-
sented in Table 8.18-1. Benet'ielation has no significant emission
potential, since the operations involve slurries of rock and water.
Emissions from dryers depend on seveial factors, including tue!
types, air flow rates, product moisture content, speed of rotation, and
the type of rock. The pebble portion of Florida rock receives much ler.s
washing than the concentrate rock from the floatiou processes. It has a
higher clay content and generates more eniss, Ions when dried. No signi-
ficant differences have been noted in gas volume or amissions from fluid
bed or rotary aryers. .\ typical dryer processing 250 tons per hour (230
metric tons per bour) of reck vlll discharge between 70,000 and 300,000
dacfm (31 - 45 dry nnr/sec) of p.'s, with a percicujate loading of 0.5 to
H.IK-2 EMISSION F.AC TORS 2/HO
-------
Phosphate
RocV
from
Mine
BenefIciation
To Control
Equl
pment
To Control
Equipment
Drying
or
Calcining
1
i
Grinding
Ground
Rock
Transfer
To
Fertilizer
Manufacturing
SC
X
Fuel
Air
Figure 8.18-1. Typical flowsheet for processing phosphate rock.
-------
5 grams/dscf (1.? - 12 grams/dry nm3). A particle size distribution of
the uncontrolled dust emissions is given in Table 8.IB—2.
Scrubbers are most commonly used to cunttul emissions from phosphate
rock dryers, but electrostatic precipitators are also u°ed. Fabric
filters are not currently being used *~o control emissions from dryers.
Venturi scrubbers with a relatively low pressure loss (12 inches of
water, or 3000 Pa) may remove 80 to 99 percent of particulates 1 to 10
micromcuers in diameter, and LO tr> 80 percent of particulates less than
1 micrometer. High pressure- drop scrubbers (30 inches of water or 7500
Pa) may have collection efficiencies of 96 to 99.9 percent for L-10
micrometer particulates and 80 to 86 percent for particles less than 1
irLcrometer. Electrostatic precipitators may remove 90 to 99 percent of
all particulates. Another control technique for phosphate rock dryers
is use of the wet grinding process, in which the drying step is
eliminated.
A typical 50 ton per hour (45 MT/hour) calciner will discharge
about 30,000 to 60,000 dscfm (13 - 27 dry nnr/dec) of exhaust gas, with
a participate loading of 0.5 to 5 g/dscf (1.2 - 12 g/dry nm3). As
shown in Table 8.18-2, the size distribution of the uncontrolled calciner
emissions is very similar to that of the dryer emissions. As .
-------
enclosed. Transfer points a^e sometimes hooded and evacuated. Bucket
elevators are usually enclosed and evacuated to a control device, and
ground rock is generally conveyed in totally enclosed systems with well
defined and easily controlled discharge points. Dry rock is nurnally
stored in enclosed bins or silos which are vented to the atmosphere,
with fabric filters frequently used to control emissions.
8.18-2. PARTICLE SIZE DISTRIBUTION OF EMISSIONS
FROM PHOSPHATE ROCK DRYERS AND CALCINERS*
Diameter (pm)
10.0
•s.o
2.0
1.0
0.8
0.5
Percent
Dryers
82
60
27
11
7
3
Less Than Size
Ca] ciners
96
8.1
52
26
10
5
Reference 1.
References for Sectiin 8.18
1. Background Information; Proposed Standards forPhosphate Rock
Plants (Draft), EPA-^0/3-79-017, U. s". Frvtronnenti-.l Protection
Agency, Research Triangle Vark, NC, Seprember 1971...
2. "Sources of Air Pollution and Their Control", Air Pol rut ton,
Volume Til, 2nd Ed., Arthur Stem, ed., New York, Academic Pres--,
1968, pp. 221-^22.
3. Unpublished data froir. phosphate rock preparation plants in Florida,
Midwest Res^cr'-h Institute, Kansas "ity, MO, Jane 1970.
^' ConLrol Techniques ror FluculJ'? Emissions, Internal document,
Office of Air Quality Planning and StarHards, U. S. Environmental
Protection Agency, Research Triangle Park, NC, pp. 4-34, 4-36 and
4-46.
Min.-nil IV.xln K I
-------
8.19 CONSTRUCTION AGGREGATE PROCESSING
The construction aggregate industry covers a range of subclas&if icatlons
of the norunetallic minerals industry (s-;e Section 8.23, Metallic Hluerals
Processing, for Information on that similar activity). Many operiMons and
processes are common to both groups, Including mineral extraction from the
earth, leading, unloading, conveying, crushing, screening, and loadout. Other
operations are restricted to specific subcate>*ories . These include wet and dry
flie milling or grinding, air classlf iration, drying, calcining, mixing, and
bagging. The latter group of operations is not generally associated with the
construction aggregate industry buC can be conducted on che same raw materials
used to produce aggregate. Two examples f»re processing of limestone and sand-
stone. Both substances Lan be used as construction mater Lulu and may be pro-
cessed further for other uses at the same location. Limestone is a common
source of construction aggregate, but it can be further milled and classified
to produce agricultural limestone. Sandstone can be processed Into construction
sand and also can be wet and/or dry milled, drltd, and air clarified into
industrial sand.
The construction aggregate industry can be categorized by source, mineral
type or form, wet versus dry, washed or unwashed, a:/d end ufies, to name but a
few. The Industry is divided in this document Into Section 8.19.1, Sand And
Gravel Processing, and Section 8.19.2, Crushed Stone Processing. Sections on
other categories of the industry will be published when data on these processes
become available.
Uncontrolled construction aggregate processing can produce nuisance pro-
blems ana can have an effect upon attainment of ambient, partlculate standards.
However, the generally large particles produced often can be controlled readily.
Some of the individual operations such as wet crushing and grinding, washing,
screening, and dredging take place with "high" moisture (more than about J .5 to
4.U weight percent). Such wet processes do not generate appreciable partlculate
emissions.
References for Section 8.19
1 ' Air Pollution Control Techniques for Nonmetalllc Minerals Industry,
EPA-4jO/3 -82-014, U. S. Environmental Protection Agency, Research
Triangle Park, NO, August 1982.
2 . Raview Emission.? Data Base And Develop Emission Factors Fo^ The
Construction Aggre^te industry. Engineer Ing-llcience, Inc., Arcadia,
CA, September 1984.
9/85 Mineral Products Industry 8.19-1
-------
8.19.1 SAND AND GRAVEL PROCESSING
8.19.1.1 Process Descriptionl-3
Deposits of sand and gravel, the consolidated giiruiiar materials result-
ing from the natural disintegration if roclc or stone, are generally found in
near-surface alluvial deposits and in subterranean and subaqueous beds. Sand
and gravel are products of the weathering of rocks and unconsolldated or poorly
consolidated materials and consist of siliceous and calcareous components.
Such deposits are r^-uuoon throughout the country.
Depending upon the location of the deposit, the materials ire excavated
with power shovels, draglines, front ^nd loaders, suction dredge pumpt or other
apparatus. In rare situation^ light charge blasting is done to loosen the
deposit. The materials are transported to the processing plant by suction
pump, earth mover, barge, truck or other near*. The processing of sand and
gravel for a specific market involves the use of different combination3 of
washars, screens and clat^if it->rs to segregate particle sizes; crushers £o
reduce oversize Material; and storage and loading facilities- Crushing oper-
ations, when used, are designed to reduce production of fines, which often
must be removed by washing. Therefore, crusher characteristics, size reduction
radios and throughput, among other factors, are selected to obtain the desired
product size distribution.
In many sand and gravel plants, a substantial portion of the Initial feed
bypasses any crushing operations. Some plants do no crushing at all. After
Initial screening, material is conveyed to a prvtion. of the plant called the
wet processing section, where wet screening anj silt renov&l are conducted to
produce washed sand and gravel. Negligible air amiss ions are expected :'r<~.m rhe
wet portions of a sand and gravol plant.
Industrial sand processing is similar to that of construction aand, Insofar
as tht initial stages of crushing and screening are concerned. Industrial sand
has a high (90 to 99 percent) quartz or silica content and is frequently obtained
from quartz rich deposits of sand or sandstone. At some plants, aft^r initial
crushing and screening, a portion of the sand may be diverted to construction
sand use. Industrial sand processes not associated with construction sand
include wet milling, scrubbing, desliming, flotation, drying, air classifica-
tion and cracking of sand grainr to form very fine sand products.
8.19.1.2 Emissions and ControliA
Dust emissions can occur from many operations at sand and gravel proces-
sing plants, such as ^onveylrg, screening, crushing, and storing operations.
Generally, these materials art wet or moist when handled, and process emissions
are often negligible. A substantial portion of these emissions may consist of
heavy particles that settle out within the plant. Emission factors (for process
or fugitive dust sources) from sand and gravel processing plants are shown in
Table 8.19.1-1. (If processing is dry, expected emissions could be similar to
those given in Section b.1.2.2, Crushed Stone Processing).
Emission factors for crushing wet materials can be applied directly or
on a dry basis, with a control efficiency credit being given for use of wet
8,19.1-1 EMISSION FACTORS 9/85
-------
materials (defined as 1.5 to 4.0 percent moisture content, or greater) or wet
suppression. The latter approach Is aoi; consistent with current practice.
The single valued fugitive dust emission far tors given In Table S.^-.l-l
nay be used for an approximation when no other information exists. Empirically
derived emission facLor equations presented in Section 11.2 of thi£ document
are preferred and should be used when possible. Each of those equations has
been developed for a single source operation or dust generating mechanism whicl
crosses industry lines, such as vehicle traffic on uuraved roads. Th» predic-
tive equation explains much of thj observed variance in measured emission
factors by relating emissions to the differing source variables. These vari-
ables may be grouped as (1) measures of source activity or expended energy
(e- g., feed rate, or speed and weight of e vehicle traveling en an unpaved
road), (2) properties of the material being disturbed (e. g., moisture content,
or content of suspendable fines in the material) and (3) climate (e. g., number
of precipitation free days per year, when en ISP ions tend to a maximum).
Because predictive equations allow for emission factor adjustment to
specific conditions, they should be used Instead of the factors given in Table
3.19.1-1 whenever emission estimates arc needed for sources in a specific sand
and gravel processing facility- However, the generally higher quality ratings
assigned to these equations are applicable only if (1) reliable values of cor-
rection parameters have beei. determined for the specific sources of Interest,
and (2) the correction parameter values 1.1*. within the range? found in develop-
ing the equations. Section 11.2 lists measured properties of aggregate materials
used in operations similar to the sand and gravel industry, and these properties
can be used to approximate correction parameter values for osa in the predictive
emission factor equations, in the event that site specific values are not avail-
able. Use of mean correction parameter values from Chapter 11 reduces the
quality ratings of tlie emission factor equations by at least one level.
Since emissions from sand and gravel operations usually are in the form
of fugitive dust, control techniques applicable to fugitive dust sources are
appropriate. Some successful control techniques used for haul roads are
application of dust suppressants, paving, TO- cc modifications, soil stabiliza-
tion, etc-; for conveyor? covering and wet suppression; for storage piles, wet
dust suppression, windbreaks, enclosure and soil stablizers; and for conveyor
and batch transfer points (loading and unloading, etc.), wet suppression and
various methods to reduce freef all distances (e. g., telescopic chutes, stone
ladders, and hinged boom stacker conveyors); for screening and other size
classification, covering and wet suppression.
Wet suppression techniques include application of wate;, chemicals and/or
foam, usually at crusher or conveyor feed and/or discharge points. Such spray
systems cr transfer points and on material handling operations have been esti-
mated to reduce emissions 70 to 95 percent.^ Spray systeaj can also reduce
loading and wind erosion emissions from storage piles of various materials 30
to 90 percent.® Cont.ral efficiencies depend upon local climatic conditions,
source properties and duration of control effectiveness. Wet suppression '.'.as
a carryover effect downstream of the point of application of water or other
wetting agents, as lonj; as the surface moisture contevn" is high enough to cause
the fines to adhere to the larger rock particles.
9/85 Mintral Products Industry 8.19.1-2
-------
TABLE 8.19.1-1. UNCONTROLLED PARTICULATE EMISSION FACTORS
FOR SAND AND CRAVrL PROCESSING PLANTS8
Uncontrolled Operation
Proce.'t Sources0
Prlaviry or aeconunty
crushing (wet)
Opin Duat Sourcei>c
I'lat acreen*
tdry product)
CoatlnouB dropc
Tranifer station
Pile foratiloa •• cracker
latch dropc
Bulk loading
Active •corage pllcal
Active day
.'aactlve day (find
•roaloo only)
Uar«>ed h«ul roada
Wat materials
Hall a ion* by Particle Star Rang* (aerodynamic dlaacter)^
Total
Particular*
NA
NA
0.014 (0,02V)
ct(.>r eqoatU" vhicl. gc re rail
provli'e oore accurate e«cloat«a of ealssloas under Bf>t-'.li^ i-vaditlo.ii, are preiecvci' In CLaiter 11. Factor
for o?ea duat iourcee art not n«ce»v«rlly r*p;«i*ntattve if cl t entire Industry or of a 'typical" Bltu'atlon
^Toeal pardculata la airborne parclclei if all alcea ID the aou.ce pluae. TSP IB wtut li neanured by a i:ai.dar
hljh voluma saaipler (aee Section il.2).
ciefer«ncea J-4.
''Refertiact'i 4*5. For coupletely wet op«r, tlane, ealaaloai are likely to be negligible.
CLI C rjfiolat ton ol data, uilog k ftctors f c r appropriate opuratloo froo Chapter 11.
'For physical, not •erodyaaaic, dlaaeter.
tKeferenfe 6. Includm the follow log dla Inct aource operitlooj la the itorag- cycl*: (1) loading of uggieget
onto B corage pllea (batch or com Icuoui dzop operations,, (2) equipnent traffic In etoragv arcn, (3) win
erosion of pill (batch or contlntioui drop oprratlona). A»naie» S to 12 hour* of actr/l.y/24 hours.
h\g/hectare (Ib/acre) of atorage/day (loclidcs irxc aaong pi lei).
'See Section 11.2 for eaplrlcal tquatiana.
References for Section P. 19.1
Air Pollution Control Tei'iuii'jijtes For Nonmetalllc Minerals Industry,
EPA-45C/3-82-014, U. -5. ilnvironmental Protection Agency, Res«arch
Triangle Park, NC, Aujusl 1982.
2. S. Walker, "Production of Sand and Gravel", Circular Number 57, National
Sand and travel Association, Washington, DC, 1954.
-* • Development Document For gf fluent LimJ it ions G iidelines And Standards -
Mineral Mining And Processing Industry, ETA-440^l-76-059b, U. S. Environ-
moi-uril Protecticn Agency, Washington, DC, July :.979.
9/8.cJ
EMISSION FACTORS
8.19.1-3
-------
* " R"?vi«w Emissions Data Baga And Develop Emission Factors For The Cons trac-
tion Aggregate Industry, Engineering-Science, Inc., Arcadia, CA, September
1984.
5. "Crushed Rock Screening Source Teat Reporto on Teata Performed at Conrock
Corp., Irvlndale and Sun Valley, CA Plants", Engineering-Science, Inc.,
Arcadia, CA, August 198A.
6- n. Cowherd, Jr., et al. , Development Of Emission Factors For Fugitive Dust
Sources, EPA--450/3-74-037Y~J7. S. Environmental Protection Agency , Research
Triangle Park, NC, June 1974.
7. R. Bohn, et al. , Fugitive Emissions From Integrated Iron And Steel Plants,
EPA-600/2-78-050, U. S. Environmental Protection Agency, Washington, DC,
March 1978.
8. G. A. Jutze and K. Axetell, Investigation Of * u g 1 1 iv a D u 1 1 _, V o 1 ume I ;
, EaiaatoDB and Control, EPA-450/3-'4-03fcat U. S. Environmental
Protect-on Agency, Research Triangle Park, NC, June 1974.
9 . Fugitive Dual Aaoegsaent At Rock And Sand facilities In The South Coast
Air Baa in, Southern California Rock Products Association and Southern
California Re»iv Mix Concrete Association, P.E.S., Santa Monica, CA,
November 197'».
8.1'}.l-4 Mineral Producfj Industry 9/85
-------
8.19.2 CRUSHED STONE PROCESSING
8.19.2.1 Process Description^
rock types processed by the rod:. and crushed slon-: industry include
limestone, dolomite, granite, traprock .sandstone, quartz and quart.ilte. Minor
types include calcareous marl, marble, shf.ll end slate. Industry c'assltlca-
Cions varv considerably and, in many cases, do no: reflect actual g^oluplcal
definitions .
Hock and crushed i;1 one products ge: arally are loosened by drilling and
blasting, then are loaded by power shov<:l or front end lojier and transported
by heavy e,' handling, and storage operations. All
of these processes cnn be significant sources of dust emissions ii uncontrolled.
Some processing operations also include washing, depending on rock r.ype and
df.-sired product •
Quarried stone normally is delivered to the processing plant by truck and
Is dumped into a hoopered feeder, usually a vibrating grizzly type, or onto
screens, as illustrated in Figure 8.19.2-1. These screens separate or scalp
*.arge bculc'cra from finer rocks that dn-not rcru.irc primary crushing, thus
reducing the load to the priraaj:y--£~rusher. Jaw, or gyratory, crushes ?rr
jsually used for initial reduction. The crusher product, normally 7.5 to 30
centimeters (3 to 12 inches) in diameter, and the grizzly throughs (undersize
material) are discharged onto a belt Conveyor and usually are transported either
';o secondary screens and crushers or to a surge pile for temporary storage.
Further screening generally separates the process flow iuto either two
or three fractions (oversi"~, undersize and throughs) ahead of th«= secondary
crurher. The oversize is discharged to r.he secondary crusher for further
reduction, and the undersize usually bypasses the secondary crusher. The
throu^he sometimes are separated, bt cause they contain unwanced fires, and are
stockpiled as crusher run material. Gyratory crushers or cone ciusht-rs are
commonly used for secondary crushing, although impact crusher? are sometimes
found.
The product of the secondary crushing stage, usually .?. .5 centimeters (1
inch) diameter or less, is transported to secondary screens for furthev sizing.
Oversize material it, sent back for recrushing. Depending or rock typr. and
desired product, tertiary crushing or grinding may be necessary, usu?liy usin^
core crusher? or l.amme rrai 1 1 s . (Rod mi llf, ball mills and hammer mills normally
are used in milling operations, which arc not considered a part of .he construc-
tion aggregate industry.) The product firom tertiary crushing may be conveyed
to a classifier, such as a dry vibrating screen system, or t-j an <-.ir separator.
Any oversize is returned to the tertiary crusher for further redrcilcn. At this
point, end products of the desired grade are convoyed or ';ruckeH directly f.o
riniehed product bins or to open area stockpiles.
9/85 Mi-iefal Products Industry 8.19.2-1
-------
FIGURE 8.19.2-1, TYPICAL STONE PROCESSING PLANT
3.19.2-2
EMISSION FACTORS
9/85
-------
In certain caser,, stone washing Is required to meet particulsr end product
specifications or demands, as with concrete aggregate processing. Crushed and
broken a "-one normally are not milled but are screened and shipped to the consumer
after secondary or tertiary crushing.
8.19.2.2 EmisBionH r.id Controls1^
Duet emissions occur from many operations* in :?tone quarrying and pro-
cessing. A substantial portion of these emissions consists of hea/y particles
thai may settle o-.it within the plant. As in other operations, crushed atone
emission sources may be categorized as either process sources or fugitive dust
sourcas. Process sources Include those for which emissions are amenable to
capture and subsequent control. Fugitive dust sources generally involve the
rountrainment of settled dust by wind or machine movement. Factors affecting
emissions from either source category include the type, quantity and surface
moisture content of the stone processed; the type of equipuunt and operating
practices employed; and -upcgraphical and climatic factors.
Of geographic and seasonal factors, the primary variables affecting uncon-
trolled particu.lf.te emiarior.t are wind and material moisture content. Wind
parameters vary with geographical location, season and weather. It car be
expected that the level of emissions from unenclosed sources (principally fugi-
tive dust sources) will be greater during periods of high winds. Tht material
moif,ture conte-it also varies with geographic location, season and weather.
Therefore, the levels of uncontrolled emissions from both process emission
source* and fugitive dust sources generally will be greater In arid regions
of the country than in temperate ones, and greater during the summer months
because of a higher evaporation rate.
The rioisture content of the material processed can have a substantial
effect on uncontrolled emissions. This is especially evident during owning,
initial material handling, pnd initial plant process operations such as primary
crushing. Surface wetness causes fine particles to agglomerate on, or to adhere
to, the faces of larger stones, with a rasulting dust suppression effect.. How-
ever, as new fine particles are created by crushing and attrition, and as the
moisture content is reduced by evaporation, this suppresslve pffect dimiaisheL
and may disappear. Depending on the geographic and climatic conditions, the
moisture content of mined rock may range from nearly zero to several percent.
Since moisture content to udually expressed nn a basis of overall weigiit per-
cent, the actual moisture amcunt per unif. area will vary with the size of the
rock beln£ handled. On a constant mass fraction basis, the per unit area mois-
ture content varies inversely with "he diameter of the rock. Therefore, the
sippresaive effect of the iroist.ure depends on both the absolute mass water con-
tent and tie size uf the rock product. Typically, a w«'t material will contain
1.5 to 4 percent water or more.
There are a large num'u^r of t.iteri.il, equipment and operating factors
vhJc.h car. influence emissions from crushing. These include: (1) rock type,
(2) feed siz.2 and distribution, (3) nuioture ruattnt, (4) throughput rate.. (5)
c.-jsher type, (6) size reduction ratl--. and (7) fines content. Insufficient
data are available to present a matri; of rock crushing emission factors
detailing the above classifications aid variable's. Data available from which
to prepare emission factors also vary considerably, for bot;h extractive testing
and p 1'j
-------
higher than those based upon
degree of reliability. Some
emissions chan from secondary
rates and visual observations
factor, on a throughput basis
factoru for either primary or
base. An emission factor for
extremely limited data. All
highly variable d«t« base
plume profiling tests, but they have a greater
teat data for primary crushing indicate higher
crushing, although factors afiectlng emission
suggest that th» secondary crushing emission
, should be higher. Table 8.19.2-1 shows single
secondary crushing reflecting .1 combined data
tertiary crushing is given, but It is based on
factors are rated low because of the limited and
TABLE, 8.19.2-1.
UNCONTROLLED PARTICULATE EMISSION FACTORS
FOR CRUSHING OPERATIONS0
Type of Crushing1*
Primary or secondary
Dry material
Wet material0
Tertiary, dry material^
Particulate Matter
< 30 pn
kg/Mg (Ib/ton)
0.14 (0.28)
0.009 (0.018)
0.93 (1.85)
< 10 urn
kg/Kg (Ib/ton)
0.0085 (0.017)
-
-
Emission
Factor
Rating
D
D
£
aBased on actual feed rate of raw material entering the particular operation.
Emissions will vary by rock type, but data available are Insufficient to
characterize these phenomena. Dash • no data.
^References 4-5. Facto:a are uncontrolled. Typical control efficiencies:
cyclone, 70 - 80%; fabric filter, 99Z; wet spray systems, 70 - 90%.
References 5-6. Refers to crushing of rock either naturally we* or after
moistened to 1.5 to 4 weight X by use of wet suppression techniques.
QRange of values used co calculate emission factor v<-s 0.0008 - 1.38 kg/Mg.
There, are no screening emission factors presented In this Section. How-
ever, the screening emission factors given in Section 8.19.1, Sand and Gravel
Processing, should be similar to those expected from screening crushed rock.
Milling of fines is also not included in this Section as this Operstici is
normally associated with non construction aggregate end uses and will be covered
elsewhere in the future when information la adequate.
Open dust source (fugitive dust) emission factors for atone quarrying and
processing are presented in Table 8.19.2-2. These factors have been determined
through tests at various quarried and processing plants.&~? The single valued
open dust emission factors given in Table 8.19.2-2 may be used when no other
information exists. Empirically derived emission factor equations presented
in Section 11.2 of this document are preferred and should be used when possible.
Because th'.'se predictive equations alloy the adjustment of emission factors for
8.19.2-4
EMISSION FACTORS
9/85
-------
10
00
TABLE 8.19.2-2. UNCONTROLLED PARTICULATE EMISSION FACTORS r'JR OPEN i/uST SOURCES
AT CRUSHED STONE PLANTS
3
1
3
Q.
n
rt
on
O.
c
CD
cc
>—'
va
I
Op^rattor.
Quarrying
Wet drilling
Blasting
Batch Drop
Truck unloading
Tiack loading
conveyor
Front end loader
Conveying
Tunnel Belt
L'npaved haul roads
".'attrial
Unfractured Stonec
Unfractured Stonec
Fractured Stonec
Crushed Stonee
Crushed Stone^
Crushed Stonec
Emissions by Particle Size Range
(aerodynamic diameter)8
iSP
< 30 vim
0.4 (0.0008)
961(A)°'e d
0.17 (0.0003)
0.17 (0.0003)
29.0 (0.06)
1.7 (0.0034)
g
PMio
< 10 urn
0.04 (0.0001)
0.2 x TSF'1
0.008 (0.00002)
0.05 (0.0001)
NA
0.11 (0.0002)
e
Unitsb
g/Mg (Ib/ton)
Ib/blast
g/Mg (Ib/ton)
g/.Hj (Ib/ton)
g/Mg (Ib/ton)
g/Mg (Ib/ton)
Enieslon
Factor
Rating
E
D
D
E
E
E
aTotal suspended particulate (TSP) Is that measured by a standard high volume sampler (See Section 11.2).
Ube of empirical equations in Chapter 11 is preferred to single value factors in this Table. Factors
in this Tahle are provided for convenience in quick approximations and/or for occasions when equation
variables can not be reasonably estimated. NA - not available.
^Expressed as g/Mg (Ib/ton) of material through primary crusher, except for front end loading, £/!!?
(Ib/ton) of material transferred, and blasting which is kg/blast.
Reference 2.
^Where A - Area blasted in ft^; D =• Depth of blast In ft; and M • Moisture content; (Adapted from Table
6.24-2. Use no
-------
specific source conditions, these equations should be used inctead of those in
Table 8.19.2-2, whenever emission estimates applicable to specific stone quarry-
Ing aud processing facility sources are needed. Chapter 1L,?. provides measured
properties of crushed limestone, as required for use In the predictive emission
factor equations.
References for Section 8.19.2
1. Air Pollution Control Techniques for Nonmetalilc Minerals Industry,
EPA-450/3-82-014, U. S. Environmental Protection Agency, Research
Triangle Park, NC, August 1982.
2. P. K. Chalekode, etal., Emissions fromthe Crushed Granite Industry:
State of the Art, EFA-600/2-78-Q21, U. S. Environmental Protection
Agency, Washingtc ., DC, February 197tf.
3. T. R. blackwood, et al., Source Asjessment: Crushed Stone, EPA-600/2-78-
004L, U. S. Environmental Protection Agency, Washington, DC, May 1978.
4. F. Record and W. T. Harnetc, Particular Emission Factors forthe
Constiuction Aggregate Industry, Draft Report, GCA-TH-CH-83-02, EPA
Contract No. 68-02-3510, GCA Corporation, Chapel Hill, NC, February 1983.
5. Review Emission Data Base and Develop Emission Factors for the Con-
struction Aggregate Industry, Engineering-Science, Inc., Arcadia, CA,
September 1984.
6. C. Cowherd, Jr., et al., Development ofEmission Factors for Fugitive Lust
Sources, EPA-450/3-74-037, U. S. Environmental Protection Agency, Research
Triangle Purk, NC, June 1974.
7. R. Bonn, -**c_ al., Fugltl/e Ejnlesions^ from Integrated Iron and Steel Plants,
EPA-600/2"-78-050,~U. S- Environmental Pro;ecLlon Agency, Washington, DC,
March 1978.
8.L9.2-6 EMISSION FACTORS {.'/65
-------
SECTION 8,20
This Section is reserved for future USK,
9/E>5 Mineral Products Industry B.20-1
-------
8.21 COAL CONVERSION
In addition to its direct use for combustion, coal can be converted
to organic, gases and liquids, thus allowing the continued use of conven-
tial oil and gas fired processes when oil and gaa supplies are not
available. Currently, there is little commercial coal ronversion in the
United Stat'b. Consequently, it is very difficult to determine which of
the many conversion processes will he commercialized in the future. The
fol] owing sections provide general process descriptions and general
eciissljn discussions for high-, medium- and lov-Htu gasification (ijasi-
laction) processes and for catalytic and solvent extraction liquefaction
processes .
1-'
8.21..1 Process Description "
8.21.1.1 Gasification - One mean? -:f converting real co an alternate
fora of energy is gasification. In this process, coal is combined wiLh
oxygen and cream to produce a combustible gas, wattle gases, char and
ash. The more than 70 coal gasification systems currently available or
being developed (1979) can be classified by -he heating value of the gas
produced and by the type of gasification reactor used. High-Btu gasi-
fication systems produce a gas with a heating value greater than 900
Btu/scf (33,000 J/tn3). Kedium-Btu gasifiers produce a gas having a
heating value between 250 - 500 Btu/scf (9,000 - 19,000 J/m'). Low-Btu
gasifiers utoduce a gas having a heating value of less than 250 Btu/scf
J/m ).
Tne majority of the gasification systems consist of lour operations:
coal prp.treatment , coal gasification, raw gas cleaning and gas beneficia-
wion. Each o*' these operations consists of several steps. Figure
8.21-1 is a flow diagram for an example coal gasification facility.
Generally, iiry coal can be gasified if proper ly pretreated. High
moisture coal? may require diving,. Some caking coals may require
partial o::idaticn to simplify ^aaifit.r operatic: . Other pretreatment
operations include crushing, sizing, ana briquetiiig of fines for feed to
fixed bed gasifiers. The ccal feed \B pulverized for fluid or entrained
bed gasifiers.
After pretiaatnr.iit , the coal enters the gasification -reaccor, where
it reacts wiLh oxygen and steam to produce a combustible gis. Air is
used as the oxygen source foi making low-Btu gas, and pure OM. 'gen is
used for making medium- ard high-Btu gas (inert nitrogen in the air
dilutes Lhe heating value of tht product) . Gasification reactors are
classified by type of reaction bed (fixed, entrained or f luidised), the
operating prepare (pressurized or atmospheric), the method of ash
removal (as i>olten slag or f.r ' as'a) , and the. number of stages in the
gasifier (one. or '.wo), tfithin etcV class, gasifiers have similar
emission? .
IP'iirrul l*nnl»ir|.» IniliMn H.2I-I
-------
The raw gas from the gasifier contains varying concentrations of
carbon monoxide, carbon dioxide, hydrogen, metnane, other organica,
hydrogen aulfide, miscellaneous acid gases, nitrogen (if air w«g used as
the oxygon source), particulates and vatn.r. Four gas purification proc-
esses may be required to prepare the gas for combustion or further
beneficirition: particulate removal, tar and oil renoval, &as quenching
and cooliv'ig, and acid £as removal. The prlnnry function of the partic-
ulate removal process AS the removal of coal dust, ash arid tar aerosols
in tne raw product gas. During tar and oil removal and gas quenching
and cooling, tars end oils are condensed, and other impurities such as
ammonia ar'j scrubbed from raw product gas using either aqueous or
organic scrubbing liquors. Acid gases such as t^S, COS, CS2, mercap-
tans, and COj can be removed from gas by an acid gas removal process.
Acid gas removal processes generally absorb the acid gases In a solvent,
from whi^ they are subsequently stripped, forming a nturly pure acid
gas waste stream with come hydrocarbon carryover. At chis point, the
raw gas is classified as either a low-Btu or medlum-3tu gas.
To produce hlgh-Btu gas, the heating value of the medium-Btu gas Is
raised by shift conversion and methanation. In the shift conversion
process, tyO and a portion of the CO arc catalytlcally reacted to form
CC>2 and Hj. After passing through an absorber for C02 removal, the
remaining CO and H2 In the product gas are reacted in a methanafion
reactor to yield CO* and H20.
There are also many auxiliary processes, accompanying a coal gasi-
fication facility, which provide various support functions. Among the
typical auxiliary processes are oxygen plant, power and steam plant,
sulfur recovery unit, watei treatment plant, and cooling towers.
8.21.1.2 Liquefaction • Liquefaction is a conversion process designer'
to produce synthetic organic liquids from coal. This conversion IE
achieved by reducing the level of impurities and increasing tne hydrogen
to carbon ratio of coal to the point thic is becomes fluid. Currently,
there are over 20 coal liquefaction processes in various stapes of
development by both industry and Federal agencies (1979). These
processes can be grouped into four basic liquefaction techniques:
- Indirect liquefaction
- Pyrolysis
- Solvent extraction
- Catalytic liquefaction
Indirect liquefaction involves the gasification of coal followed by the
car.aiytic conversion cf the product gas to a liquid. Pyrolysis lique-
faction involves heating coal to very high temperatures, thereby crack-
ing the coal into liquid and gaseous products. Solvent extraccicn uses
a solvent generated within the process to dissolve the <-oal and to
transfer externally produced hydrogen to the i:oal molecule1?. Catalytic
liquefaction resembles solvent extraction, except that hydrogen is added
tc the coal w.ith the aid of a catalyst.
H.21-2 EMISSION FUTORS 2/KO
-------
Coal Preparation
'Dryt-iR
"Crushlii,:
JPartia; '1: l-d^r' ji.
"Briquet ui(i
Ccal
nr«purat ion
Oxygen (!t
Air ~
aslfiur
I prnducf ^,a^
Sulfur f *Tatl Cas
Shite
Convt rjio
I
J praduv: gas
High-It,:
Figure 8.21-1. Flo«,v diagram of typical coal gasification plant.
*«lJrii*nil 1'i
H.2I-3
-------
Figure 8.21-2 presents the flow diagram of a typical solvent extrac-
tion or catalytic liquefaction plant. These coal liquefaction processes
consist of four basic operations: coal pretreatment, dissolution and
liquefaction, product separation and purification, and residue
gasification.
Coal pretreatment generally consists of coal pulverizing and
drying. The dissolution of cr.al is best effected if the coal is dry and
finely ground. The heater used to dry coal ii typically coal fired, buc
it may also combust low-BTU value product streams or may use waste heat
from other sources.
The dissolution and liquefaction operations are conducted in a
series of pressure vessels. In these processes, the coal is mixed with
hydrogen and recycled solvent, haated to high temperatures, dissolved
and hydrogenated. The order in which these operations occur varies
among the liquefaction processes and, in the case of catalytic liquefac-
tion, Involves contact with a catalyst. Pressures in these processes
range up to 2000 psig (14,000 Fa), and temperatures range op to 900°F
(480°C). During the dissolution and liquefaction process, the coal is
hydrogenated to liquids and some gases, and the oxygen and sulfur in the
ccal are hydrogenated to ^0 and
After hydrogenitlon, the liquefaction products are separated,
through a series of flash separators, condensers, and distillation
units, into a gaseous stream, various product liquids, recycle solvent,
and mineral residue. The gases from the separation process p.rn sepai-
ated further by absorption into a product gas stream and A waste acid
gas stream. Tie recycle solvent is returned to the dissolution/lique-
faction process, and the mineral residue of char, undJssolved coal and
ash is used in a conventional gasification plant to produce hydrogen.
The residue gasification plant closely resembles a conventlal htgh-
Btu coal gasif action plant. The residue is gasified Jr. the presence of
oxygen and steam to produce CO, 0*2 , HzO, other *aste gases, and partic-
ulates. After treatment for removal of the waste gases and particulates,
the CO and HjO go into a shift reactor to produce C02 and additional H2 •
The H2 enriched product gas from the residue gaslfler is used subsequently
in the hydrogenation of the coal.
There are also many auxiliary processes accompanying a coal lique-
faction facility which provide various support functions. Among the
typical auxiliary processes are oxygen plc.nt, power and titeam plant,
sulfur recovery unit, water treatment plant, cooling towe-rs, and sour
water strippers.
8.21.2 Emissions and Controls
Although characterization data are avallabe for aome of the T?ny
developing coal conversion processes, describing these data in detai-
would require a viore extensive discussion than possible here. Go, th." 3
H.2I-I EMISSION FACTORS 2/80
-------
Coal
preparation
Coal I
rilssu Lution
and I
liquefaction I
Waste
Gases
purif(ratloi
Pro hicr
separation
Iiqulds
»6Tveo t "
is "T
Liquids I
aeparacloo I
Hydrogen
Gasification
"Shift cOTii-crsloo
°Ai Id gas rpmv
'Oehyd'atlon
Mineral tcaldue
Waste gases
Praduct
Product
Figure 8.21-2. Flow diagram for an example coal liquefaction Facility.
-------
T.nble 8.21-1. SUMMARY OF EMISSIONS FROM COAL GASIFICATION PLANTS
1-3
Operation/Enission Source/Stream
Coal Pretreatment
Storage, handling and crushing./
sizing - Dust emissions
CharacterJ.zation of Emission Summary of Emission Control Choices
/.
>
Drying, partia.1 oxidation
and brtquerinR - Vent gases
•f.
Coal Gasilication
Feeding - Vent gases
Emissions from coal storage,
handling and crushing/sizing
mainly consist of co^l dust.
These emissions vary from
site to site, depending on
wind velocities, coal and
pile size-, and water
content.
These emissions comprise
coal dust and co~ihustlon
gases along with a variety
of organic compounds devola-
' ilized from the coal.
Organic species have not
been determined.
These gases contain ail the
hazardous species found In
th» raw product gas exiting
the gasifier, including J^S,
COS, CS2, S02, CO, NH3, Crtu,
KCN, tars ?nd oils, parci-
cu.lat.Rs. and tra^e organics
auu inorganics. The size
and c-jmpo.sition of this
stream depend on the type
of pasifiei.', e.g., fiv-idized
Water sprays and poi/mcr coatings
are used to control du.«=t. emissions
from coal storage pLles. Water
sprays and enclosed equipment are
vented to a baphouse to reduce or
capture particulars frum coal
handling. Emissions from crushing/
sizing are also usually vented to a
baghousc or other partici'iate
control device.
In addition tr> ^articulate control
devices, afterburners may he needed
to destroy organic species;.
This stream coulJ represent a sign
ificant environmental problem.
Control could include scrubbing or
Incineration (to capture or destroy
'he most hazardous species), or
venting to the raw product gas or
Rasifipr inlet air. Th«; desireo
control depend:: on th^- type and size
of gasiffcarion facility. Scr^w
fed conveyors can be used instead of
lock hoppers.
-------
Table S.21 I (c...iL.). SUI^IARY OF MISSIONS FROM COAT, GASIFICATION PLANTS
1'3
Operation/Emission Source/Stream Characterization of Emission Summary ol Emission Control Choices
Ash removal - Vent gases
Startup - Vent gas?.s
bed gasifiern emit
lally fewer tar? and oils
than fixed bed gasifiers.
Emissions from ash removal
and disposal depend on the
type of gas4Cier. Ash dust
will be released from all
gasifiers that are not
slagging or agglomerating
a*>t< units. If contaminated
water is used for ash quench-
ing, volatile organic and
inorganic species may be
released from the quench
1iquor.
This vent gas initially
resembles a coal combustion
gas in composition. As the
operating temperature of
the gas increases, the
startup gas begins to
resemble the raw product
These emissions have not been
sufficiently characterized to recom-
mend necessary controld. Partlculate
or organic emission controls could he
needed. Clean water nay be used for
quenching to avoid the potential
emission of hazardous volatile oceanic
and inorganic species.
A flare ran Incinerate the combustible
constituents in the startup gas, but
heavy tars and ccal participates will
affect the performance of the flare.
Potential problems with tars and
partlculates can be avoided by using
charcorl or ccke as the startup fuel.
Fugitives
These emissions have not
b>ien characterized, but they
comprise hazardous species
found in the raw product gas
such as H;S, COS, CS2, CO,
HCN, Clt, and other?.
Control methods mainly involve gocd
maintenance and operating practices.
-------
Table 8.21-1 (cont.). SUMMARY OF EMISSIONS FROM COAL GASIFiCATTCK PLANTS1"3
Operation/Emission Sonrce/JStream Characterization of "mission Summary of Emission Control Choices
Raw Gas C1.eaning/rtcneficiatio;i
Acid Gas Removal - Tail
f_
X
Auxiliary Operations
Sulfur recovery
Power and steam generation
These emissions bsve not
been characterized, but they
comprise hazardous species
found ir the various gas
streams. Other emissions
result from leaks from pump
seals, valves, flanges and by-
product storage tanks.
Control methods mainly involve good
maintenance and operating practices.
The composition of this
stream highly depends on the
kird of acid gas removal
employed. Processes
featuring the direct removal
and conversion of sulfur
species in a single step
(e.g., the Stretford process)
produce tail gases contain-
ing small amounts of NH3
and other species. Pro-
cesses absorbing and
subsequently desorbing a
concentrated acid gas
stream require a sulfur
recovery process to avoid
the emission of highly toxic
gase- having quantities of H2S
See Secf.icn 5.18
Section 1.1
Some tail gas streams (from tht
Stretforr1. process, for example) are
p^robably not very hazardous. These
streams have not been characterized,
nor have control technology needs
been demonstrated. Tail gases from
other processes always require the
removal of sulfur species. Trace
constituents such as organics, trace
elements and cyanides affect th
performance rf the auxili?*-y sulfur
removal pro
-------
M
^
:c
Table 3.21-1 (cont.). SUMMARY OF EMISSIONS FROM COAL GASIFICATION PLANTS
1-3
}'jeration/Emisslon Source/Stream Characterization of Emission Summary of Emission Control Choices
Wastewater Treatment -
Expansion gases
Cooling lovers - Exhaust gas
These streams comprise
volarile organic and in-
organic species that desorb
from quenching/cooling
liquor. The streams potent-
ially Include all the
hazardous species found in
the product gas.
Emissions from cooling
towers are usually minor.
However, if contaminated
water is used as cooling
water makeup, volatile
organic and inorganic
species froci the con-
taminated water could be
released.
These streams could pose significant
environmental problems. Poteatial
controls are generally similar to
those needed to treat coal feeding
vent gases.
The potential emission of hazardous
volatile organic and inorganic species
may be avoided by using clean water
for cooling.
X
K.
-------
Section will cover emissions and controls for coal conversion processes
on a qualitative level only.
8.21.2.1 Gasification - All of the major operations associated with
low-, medium- and high-Btu gasification technology (coal pretreatment,
gasification, raw gas cleaning, and gas beneficiation) can produce
potentially hazardous air emissions. Auxiliary operations, such as
sulfur recovery and combustion of fuel for electricity and steam genera-
tior, could account for a major portion of the emissions from a gasifica-
tion plant. Discharges to the air frcm both major and auxiliary operations
are summarizpd and discussed In Table 8.2~.-l.
Dust emissions from coaT storage, handling and crushing/sizing can
he controlled with available techniques. Controlling air emissions from
coal drying, briquuting and partial oxidation processes is more difficult
because of the volatile organics and possible trace metals liberated as
the coal is heated.
The coal gasification process itself appears to be the most serious
potential source of air emissions. The feeding of coal and the with-
drawal of ash release emissions of coal or ash dust and organic and
inorganic gases that are potentially toxic and carcinogenic. Because of
their reduced production of tare- and condensable organics, slagging
gasifiers pose less severe emission problems at the coal inlet and ash
outlet.
Casifiers and associated equipment alao will be sources of potenti-
ally hazardous fugitive leaks. These leaks may be more severe from
pressurized gasii'iers and/or gaslfiers operating at high t3mperaturectiv£ly). Gases stripped or dcscrbed frcm
process wastewaters are potentially hazardous, since they contain many
of the components found in ihe product gas. These include sulfur and
nitrogen species, organics, tnd other species that are toxic ami potenti-
ally carcinogenic. Possible controls for these, gasus include incinera-
tion, byproduct recovery, or venting to f.he raw product gat- or inlet
KMISSION FACTORS 2/8O
-------
ti
"V.
X
Table 8.21-2. SUMMARY OF EMISSIONS FROM COAL LIQUEFACTION FACILITY
Operation/Emission Source/Stream Characterization of Emission Summary of Emission Control Choices
Coal Preparation
Storage, handling and
crushing/sizing
Emissions primarily consist
of fugitive coal dust gen-
erated at transfer points
and points exposed to wind
erosion. A potentially
significant source.
Water sprays and polymer coatings are
used to control dust fros storage sites,
Water sprays and enclosures vented to
baghouses are effective on crushing
and sizing operations.
Drying
Emissions include coal dust, Scrubbers, electrostatic precipitators,
combustion produces from
heater, and organics
vo atilized from the coaJ.
A potentially significant
particulate souice.
and baghouses are effective coal dust
controls. Low drying temperatures
reduce organics formation.
Coal Dissolution and
LiquefAction
Process heater (fired with
low grade fuel gas)
Emissions consist of com'iug- Fuel desulfuvization for S02 control
tion products (particulates, and combustion modifications for
CO, SC2, KOx and HC). reduced CO, HC and
Slurry mix tank
Product Separation and
Liquefaction - Sulfur recovery
plant
Evolution of dissolved gases
from recycle solvent (HC,
acid gases, organics) due to
low pressure (atmospheric)
of tank. Some pollutants are
toxic even in small quantities.
Controls might include scrubbing,
incineration or venting to heater
combustion air supply.
Tail gases containing acids
(H2S, S02, COS, CS2 NH3 and
particulate sulfur).
Venting _o tail gas treatment plant,
or operating sulfur recovery plant at
higher efficiency.
-------
Table 8.21-2 (cont.). SUMMARY OF EMISSIONS FROM COAL LIQUEFACTION FACILITY
Opgrat ion /Eml ss ion Sour c e / S t ream Cnaracterization of Emission Summary of Emission Control Choices
Residue Gasification See 8. 21. 2.1, in text.
Auxiliary Processes
Pnver and steam generation
Waste water system
Cooling towers
Fugitives
See Section 1.1,
Volatile organics, acid
gases, ammonia and cyanides,
which evolve from various
wr.sLe water collection and
treating systems.
Any cnemical in the facility
can leak to cooling water
system from leaking heat
exchangers and can be
stripped to the atmosphere la
the cooling tower.
All organic and gaseous cam- Good housekeeping, frequent main-
Enclosure of the waste water system
and venting gases from system to
scrubbers or incinerators.
Good heat exchanger maintenance and
surveillance of cooling water quality.
pounds in plant can leak
from valves, flanges, seals
and sample ports. This may
be the largest source of
hazardous organics.
tenance and selection of durable
components are major control
techniques.
-------
air. Cooling towers are usually minor emission sources, unless the
cooling water la contaminated.
8.21.2.2 Liquefaction - The potential exists for generation of signifi-
cant levels of atmospheric pollutants from every major operation in a
coal liquefaction facility. These pollutants include coal dust, combust-
ion products, fugitive o' panics and fugitive gases. The fugitive
organica and gaaei could Include carcinogenic polynuclear organics and
toxic gases such as metal jarbonylp, hydrogen sulfldes, ammonia, sulfu-
rous gases, and cyanides. Many studies are currently underway to charac-
terize these emissions and to establish effective control methods.
Table 8.21-2 presents Information now available on liquefaction emissions.
Emissions from coal preparation inclr.de coal dust from the many
handling operations and combustion products from the drying operation.
The most significant pollutant from these operations is the coal dust
from crushing, screening and drying activities. Wetting down the surface
of the coal, enclosing the operations, and venting effluents to a
scrubber or fabric filter are effective means of particulate control.
A major source of emissions from the coal dissolution and lique-
faction operation is the atmospheric vent on the slurry mi;, tank. The
slurry mix tank is used for mixing feed coal and recycle solvent. Gasee*
dissolved in tne recycle solvent stream under pressure will flash from
the solvent as it enters the unpressurized slurry mix tank. These gases
can contain hazardous volatile organics and acid gases. Control tech-
niques proposed for this soarre include scrubbing, incineration or
venting to the combustion air supply for either a power plant or a
process heater.
Emissions from process heaters fired with waste process gas cr
waste liquids will consist cf standard combustion products. Industrial
combustion emission sources end available controls are discussed in
Section 1.1.
The major emission source in the product separation and purifi-
cation operations is the sulfur recovery plant tail gas. This can
contain significant levels of acid or sulfurous gaecs. Emission factors
=ind control techniques for sulfur recovery tail gases are discussed in
Section 5.18.
Emissions from the residue gasifier used to supply hydrogen to the
system are very similar tn those for coal gasifiers previously discussed
in this Section.
^-missions fron auxiliary processes include combustion products from
oasite steam/electric power plant and volatile emission!* from the
wastewater s>stem, cooling towers and fugitive emission sources.
Volatile emissions from cooling towers, wastewater .systems and fugitive
emission aources posslhly can include e\rery chemical compound present in
the ,,]nnt. These sourr.es will bt: th i most significant and most difficult
2/HO .Mii.
-------
to control in a coal liquefaction facility. Compounds which can be .
present include hazardous organics, metal carbonyls, trace elements such
as mercury, and tc.cic gases such as CO, H2S, HCN, NH3, COS and CS? .
Emission controls for wastewater systems involve minimizing the
contamination of water with hazardous compounds, enclosing the waste
water systems, and venting the wastewater systems to a scrubbing or
incineration system. Cooling tower controls focus on good heat exchanger
maintenance, to prevent chemical leaks into the system, and on surveil-
lance of cooling water quality. Fugitive emissions from various valves,
seals, flanges and sampling ports are individually small but collec-
tive]"/ very significant. Diligent housekeeping and frequent maintenance,
combined with a monitoring program, are the best controls for fugitive
sources. The selection of durable low leakage components, ^uch as
double mechanical seals, is also effective.
References for Section 8.21
1. C. E. Burklin and W. J. Moltz, Energy Resource Development 5>ster!.
EPA Contract No. 68-01-1916, Radian Corporation and The University
of Oklahoma, Austin, TX, September 1978.
2. E. C. Cavana-jgh, et al.. Environmental Assessment Data Base for
Low/Mediun-BTUgasification Technolog), Volume 1,
EPA-6QO/7-77-125a, U. S. Environmental Protection Agency, Research
Triangle Park, NC, November 1977.
3. P, W. Spaite and C. C. Page, Technology Oyerview; Low- and Mcdiuni-
BTU Cocil Gasification Systeus. EFA-600/7-78-061, U.S. Environmental
Protection Agency, Research Triangle Park, NC, Marrli 1978.
K.2I-M liMISSION FACTORS 2/ttO
-------
8.22 TACONITE ORE PROCESSING
8.22.1 General1"2
More than two thirds of the iron ore produced in the IT..ted State.--- TOL
making iron consists of 'aconite con.ontrate pellets. Taconite is a low
grade iron ore, largely from deposits .n Minnesota and Michigan, but from
other areas as we1!. Processing of taconite consists of crushing and
grinding the ore to liberate i ronbeanng particles, concentrating the ore
by separating the particles from the waste material (gangue), and palletiz-
ing the iron ore concentrate. A simplififd flow diagram of these process-
ing steps is shown in Figure 8.22-1.
Liberation - The first step in processing crude taconite ore is crushing
and grinding. The ore must be ground to a particle size sufficiently close
to the grain size of the ironbearing mineral, to allov for a high degree of
mineral liberation. Most of the taconite used today rtquires very line
frinding. The grinding is normally performed in three or four stages of
dry crushing, followed by wet grinding in rod mills and ball mills. Gy-
ratory crushers are generally used for primary crushing, and cone crushers
are used for secondary and tertiary fine crushing. Intermediate vibrating
screens remove unders^ze material from the feed to the next crusher and al-
low for closed circuit operation of the fir* crushers. The rod and ball
mi] Is are also in closed circuit with classification systems such as cy-
clones. An alternative is to feed same coarse "res directly to wet or dry
seroiautcgenous or autogenous grinding mills, then to pebble or ball mills.
Ideally, the liberated particles of iron minerals <'id barren gangue should
be removed from the grinding circuits as soon as they are formed, with
larger ^articles returned for further grinding.
Concentration - As the iron ore minerals are liberated by the crushing
steps, the •;. icribearing particles must be concentrated. Since only about 33
percent of the crude Vaconite becomes a shippable product for iron making,
a large amount of gdnguc is generated. Magnetic separation and flotation
are most commonly used for concentration of the taconite ore.
Crude ores in whirh most of the recoverable iron is magnetite (or, an
rare rases, maghenutcj are normally concentrated by magnetic sepatition.
The crude ore may contain 30 to 3S percent total iron by assay, but theo-
retically only ibout 75 percent of this i... recoverable magnetite. The re-
maining iron becomes part of the gangue.
Nonmagnetic taconitH ores are roncentrated by froth flotation or by a
combination of selective f ] occalation and f lot.-iti on. The method is deter-
mined by the differences in surface acf.ivilv ^riween the iron and gangue
particles. Sharp separation is often difficult.
Various combinations of magnetic sej. "ir.it.ion and flotation may be used
to concentrate ores containing various iron minerals (magnetite and hema-
tite, or h'.aghemitr) or wide ranges of mineral grain sizes. flotation is
also often used as a final polishing operation or. magnet-L .c.nc.?ntrates.
5/81 Mineral Produc.s Industry 8.22-1
-------
S3
M
I
ro
K.IM
Ta.o.
On.-
c/:
C
?0
LO
sLtc JILJ;„. I Tjlim^a *
I iep^' rj[ uT
IjJ 1 I. ii» I
T.ii 11 «,<•••
fh !<• knur
|Lfiv
jCftnci-nr rat t
Slur.ge
^ J 1 ravt ilntt j^ S i*-rn
! 1 t"-1" I _.
T
I I jultlslili
1 T!!"' r
i i
Chip
He.riiiJ
1'ClltLJ „
r:
Cnn! i- r
"I
^_J ___
PL-11,T
Tr JIIB! t-r
' --T
l .
Figure a.22-1. TacoriLe ore processing plant. (Process emir.sions are indicated by |-
-------
Pelletization - Iron ore concentrates must be coarser than about No. 10
mesh to be acccptabl• as blast furnace feed without tuither treatment. The
finer concentrates are agglomerated into small "green" pellets. This is
normally accomplished by tumbling moistened concentrate with a balling drum
or balling disc. A binder additive, usually powdered bentonite, may be
added to the concentrate to improve ball formation and the physical quali-
ties of the "green'1 balls. The bentunite is lightly mixed with the cave-
fuily moistened feed at 4.c> to 9 kilograms per meigagram (10 to 20 lb/ton)
fhe pel]ets arc hardened by a procedure called induration, the drying
and heating of the greeii balls in an oxidizing atmosphere at incipient fu-
sion teaiperature [1290 to 1400°C (2350 to 2^0°?), depending on tne compo-
sition of the balls] for several minutes and then cooling. Four general
types of indurating apparatus ace currently used. T^ese are the vertical
shaft furnace, the straight grate, the circular grate end grate/kiln. Most
of the large plants and new plants use the grate/kiln. Natural gas is most
commonly used for pellev induration now, but probably nol in the future.
Heavy oil is being used at a few plants, and coal may be used at future
plants.
In the vertical s ,1r* furnace, the wet green balls are distributed
evenly over the top c: i_n<- slowly descending bed of pellets. A rising
stream of gas of controlled temperature and composition flows counter to
the descending bed of pellets. Auxiliary fuel combustion chambers supply
hot gases midway between the tup and bottom of the furnace. In the
straight grate apparatus, a continuous bed of agglomerated green pellets is
carried through various up and down flows of gases at different tempera-
tures. The grate/kiln apparatus consists of a continuous traveling grate
followed by a rotary niln. Fellets indurated by the straight grate appara-
tus are coole-1 on an extension of the grate or in a separate cooler. The
grate/kiln product must bf» cooled in a separate cooler, usually an annular
rosier ,/ith countercrurrent airflow.
1 -3
8.22.2 Emissions anrl C-jiitrols
Emission sources in taconir.e ere processing plants are indicated in
Figure 8.22-1. Pa'ticulate emissions also arise from ore mining opera-
tions. Uncontrolled emissidi factors for the major processing sources are
presented in Table 8.22-1, and control efficiencies in Table 8.22-2.
The ta^onite ore is handled dry through the crushing stages. All
crushers, size classification screens and conveyor transfer points are ma-
jor points of partirulate emissions. Crushed or? is normally ground in wet
rod and ball mil If;. A few plants, however, use dry autogenous or snmi-
autogenous grinding and ha^e higiior emissions than do conventional plants.
The uie remains wet through the rost of the beneficiatic/n process, so par-
ticulate emissions after crushing are generally insignificant.
The first, source of emissions in the pellet izing process is the trans-
ler and blending of bentonite. There irn 1,0 other significant emissions in
the balling section, sinre Lhe iron ore concentrate is normally too wet to
cause appreciable dusting. Additional emission points in the pellctizing
profess include thu' main waste gas stream from the indurating furnace,
5/83 Mineral Products Industry 8.22-3
-------
TABLE 8,22-1 UNCONTROLLED ^ARTICULATE EMISSION
FACTORS IOR TACONITE ORE
PROCESSING3
EMISSION FACTOR RATING: D
"
Source
Fine crushing
Wo s t e ga s
Pellet handling
Grate discharge
Grate feed
Bentonite blending
Coarse crushing
Ore transfer
Bentonite transfer
kg/Mg
39.9
14 6
1 .7
0.66
0.32
0.11
0.10
0.05
0.02
_ . . b
Emissi ons
Ib/ton
79.8
29.2
3.4
1,32
0.64
0.22
0.20
0.10
0.04
, Reference 1. Median
values .
produced.
pellet handling, furnace transfer points (grate feed and discharge), and
for plants using Uio %iate/kiln furnace, annular coolers. In addition,
tailings basins and unpaved roadways can be sources of fugitive emisrions.
Fuel used to fire the indurating furnace generates low levels of sul-
t'ur dioxide emissions. For a natural gas fired furnace, these emissions
art about 0.03 kilograms of S02 per megagrnm of pellets produced (0.06 lb/
ton). Higher S02 emissions (about 0.6 to 0.7 kg/Mg, or 0.'^ to 0.14 lb/
ton") would result from an oil or coal fired furnace.
Particulate emissions from t^conire ore pr^cest-ing plants are con-
trolled by a variety of devices, including cyclones, imilticlone?, roto-
clones, scrubbers, baghouses and electrostatic precipit&tors. Water sprays
are also used to suppress dusting. Annular coolers art generally left un-
controlled, becausi- their mass loadings of particulates are small, typi-
cally less than 0.11 grams per cubic meter (0.05 p,/scf)
The largest source of particulate emisrions in taconite ore nines is
traffic on unpaved haul roads.3 Table 8.22-3 presence size specific emis-
sion factors for this source determined through scurce testing at one taco-
nite mine. Other significant particalace emissioa sources at tacoaitr.'
ininss are wind erosion and blasting.0
As an alternative to :he single valued emission factors for open dust.
sources given in Tables 8.22-1 and 8.22-3, empirically derived emission
8.22-4 Mineral Products Industry
-------
TABIF 8. -2-2.
CONTK01. "FFICIENCIES FOR COMBINATIONS OF
CONTROL DEVICES AND SOb'RC£Sa
Control
Course Or«
< rw'ilng I ranker
fine Penlonite Denlonite
transfer hlentfing fred
Grate
3
c
c
y.
Srruhhrr
Cyclonr
ffc 11' c1one
B.ig collecior
F,ln I rosI»L ir
preripi tator
Dry mechanical
col
Centri fug.il
ccllecloi
99.9(2}«
99(4)e
95(10 If
99(2)> 97(4)
85(1)1
92(2)f
88(7)f
gg(l)f
9« 7(1)f 99.J(Z)f
99 .Ifljf 9^OB
97(IO)n
97(l9)r
98(l)f
99.7(7)f
99.7fl)f
85(l)f
88(1)1
9H(l)r
8R(l)f
99. <•(!)••
99.3(2)f
99.7(I)T
99 (•).; r
97.S(l)p
98!
Reference 1. Control r((ir,r,tcifs rrt fPCprcss.'J as percent rfJuction. MuBib»r« in parrnlh -s*« ire vhc nimhrr pf
indiLatc-1 comblnat i^.. s vilh \.'nr stated rfficlrnry The lettfrs •, f, r denote vhrthrr I h<- statui rfflrifncirn
«rrr rtaxrd upon msnufarturrr'« rating fn), firiff testing (f), or . Et inn t lent (r). BlunKs IndiciLr thai no
such coabinitieni of sourer ami tonlr-l lrrhno)o/(y arr known to eiiil, or thai no diti nr I hr ^fflrirn-Y 01
the roohination ire ivxll^hl*.
-------
TABLE 8.22-3.
lUCONTRCLLED PARTICIPATE EMISSION FACTORS FOR
HEAVY DUTY VEHICLE TRAFFIC ON HAUL ROADS AT
TACONITE MINES3
Surface
material
Emission factor by aerodynamic diameter
30 ,jin
IIEUCl ., .
Units
< 15
10 M™
5 pm < 2.5
Emi ss ion
Factor
Rit ing
Crushed rock
and gla-
cial till
Crushed
taccnite
and waste
3
ll
2.6
9.3
2.2
7.9
1.9
6.6
1.7
S.2
1.5
5.2
1.1
3.9
0.90
3.2
0.62
2.2
0.54
1.9
kg/VKT
Ib/VMT
kg/VKT
Ib/VMl
D
D
Reference 3. Predictive emission factor equations, which generally pro-
vide .iipn> accurate estimates of emissions, are presented in Chapter 11.
VKT = Vehicle kilometers t'-aveled. VM1 = Vehicle miles traveled.
factor equations are presented in Chapter 11 of this document. Each equa-
tion was developed for a source operation defined on the basis of a Dingle
dust generating mechanism which crosse.. industry lines, such is vehicle
traffic on unpaved roads. The predictive equation explains much of the ob-
served variance in measured emission factors by relating emissions to pa-
rameters which character!?-' source conditions. These parameters may be
grouped into three categories: 1) measures of source activity or energy
expended (e.g., the spepr) and weight of a vehicle traveling on an unpaved
road), 2} properties of the material being disturbed (e.g., the content of
suspendable fines in the suiiace material on an unpaved road),, 3) climatic
parameters (e.g., number of precipitation free days per vear, when emis-
sions tpnd to a m.iximuni) •
Because the predictive equations allow fcr emission factor adjustment
to specific source conditions, the equations should be used i-.i place of
tht single valued facto-s for open dust sources, in Tables &.L2-] and
8.22-3, if emission estimates for sources in a specific taconitt oro mine
or processing facility are needed. However, the generally higher quality
ratings assigned 1.0 the equations are applicablr only if 1) reliable values
of correction parameters have been determined for the specific source;: of
interast and 2) the correction parameter values lie within the ranges
tested in developing the equations. Chapter 11 lists measured properties
of aggregate process materials and road surface materials found in taccnite
mining ,-nd processirg facilities, which can be useu to estimate correction
parameter values for the predictive emission factor equations, in the even';
t.ial site specific values are not available. Use oil mean correction parair-
CLCL values from Chapter 11 reduces the quality ratings of r.he emission
factor equations by onf: level .
8.22-6
EMISSION FACTORS
3/83
-------
References for Section 8.22
1. J. P. Pilney ard G. V. Jorgensc.ii, Emissions from Iron Ore Mining, Ben-
ficiation and Palletization, Volume 1. EPA Contract No. 68-02-2113,
Flidwest Research Institute, Minnetonka, MM, June 1978.
2. A. K. Reed, Standard Support and "nviroiunental Impact Statement for
the Iion Ore Beneficiation Indastiy (Draft), EPA Contract No. 68-02-
1323, Battelle Columbus Laboratories, Columbus, OH, Decemner 1976.
3. T. A. Cuscino, £t_al_1, Taconite Mining Fugitive Emissio.iS .^tudy,
Minnesota Pollution Control Agency, Roseville, MN, June 1979.
5/83 Mitral Products Industry 8.22-7
-------
8.23 METALLIC MINERALS PROCESSING
5.23.1 Process Description1"^
Metallic mineral processing typically involves the mining of O>:Q,
either from open pit or underground mines; the. crushing and grinding of ore;
the separation of valuable minerals fron: matrix rock through various concen-
tration steps; and at some operations, the drying, calcining or pelietizing
of concentrates to e.asR further handling and refining. Figure 8.23-1 is a
general flow diagram for nit-ralHc mineral processing. Very few metallic
mineral processing facilities wil~ contain .ill of the operations depir.ruri in
this Figure, but nli .-facilities will use at least some of these operations
in the process of separating, valued minerals from the matrix rock.
The number of crushing steps necessary tc reduce ore tc the proper si^e
will vary with the ty;je if ore. H.ird ores, including some copper, gold, iron
and molybdenum ores, nay reqaire as much as a tertiary crushing. Softer
ores, such as sore; uranium, bauxite and tl tani jiu/zirconium ores, require
little or no crujiiing. F_r.rtal comminution of both hard and soft ores is often
accomplished by grinding operations using medj.i sucii as balls or rods of var-
ious materials. Grinding is most often performed with an ore/water slurry,
which reduces particulate emissions to negligible levels. When dry grinding
processes are used, particulate emission;; can be considerable.
After final size reduction, the beneficia .ion of the ore increases the
concentration of valuable minerals by separating them from the matrix rock.
A variety of physical and chemical processes Li used tc concentrate the
mineral. Most often, physica- or chemical separation is performed in an
aqueous environment which eliminates particulnt:e emissions, although some
ferrous and titaniferous minerals are separn.ce.i.1 by magnetic or electrostatic
methods in a dry environment.
The concentrated mineral products may be cried to remove surface
moisture. Drying is most frequently done in nuturil gas fired rotary
dryers. Calcining or palletizing of some products;, such as alumina or iron
concentrates, are also performed. Emissions from calcining aiul pelletizing
operations are not covered in this Section.
8.23.2 Process Emissions7-^
Particulate emissions result from metallic miaeral plant operations
Tjch as crushing aid dry grinding of ore; drying cf. concentrates; storing
and reclaiming of ores and conrpnf r.ir^s from storage bins; transfer of
materials; and loading of fin.il prniuits for shipment. Mrticulat?. emission
factors ai/e provided in T-'.blt> H.t3-l for varioi ? metallic mineral process
operations, including pr-'r-.ary, secondary and tertiary crushing; dry grinding;
drying; and material handling and tnn^fer. Fugitive emissions are also
possible from roc'tds and open stockpC.es, factors for which are ir. Section
11.2.
0/82 MiniTrt! I'ri>durt.s Industry
-------
I—Ore From Mines
Primary
Crushers
Storage
Bin(s)
Secondary
crushers
Grinders
Product
Luadout
I ryers
Beneficiatdon
T
Tailings
Figure 3.23-1. A metallic mineral processing plant.
The emission factors in Table 8.23-1 are for the process operations as
a whole. At. most metallic mineral processing plants, each process operation
will require several types of equipment. A single crushing operation likely
will Include a hopper or ore dump, screenfs), crusher, surge bin, apron
feeder, and conveyor belt transfer points. Emissions froc. these various
pieces of equipment ar« often ducted to a single control device. The emis-
sion factors provided :ln Table 8.23-1 for primary, secondary ".'id tertiary
crushing operations
-------
The emission factors for dryers in Table 8.23-1 include- transfer points
integral with the drying ope i at ion. A separate emission factor is; provided
for dryers at titanium/zirconium plants that use dry cyclones for product
recovery and for emission control. Titanium/zirconium sand type ores do not
require crushing or grinding, and the ore is washed to remove humic and clay
material before concentration and drying operations.
At some metallic mineral processing plants, material is stored in
enclosed bins between process operations. The emission factors provide;! In
Table 8.23-1 for the handling and transfer of material should be applied to
the loading of material into storage bins and the transferring of material
from the bin. The emission factor "ill usually be applied twice to a storage
operation, once for the loading operation and once for the reclaiming oper-
ation. If material is stored at multiple points in the plant, the emission
factor should be applied to each operation and should apply to the material
being stored at each bin. The material handling and transfer factors do not
apply to small hoppers, surge bins or transfer points that are integral with
crushing, drying or grinding operations.
At some large metallic mineral processing plants, extensive material
transfer operations, with numerous conveyor belt transfer points, may be
required. The emission factors for material handling anr. transfer should be
applied to each transfer point that Is not an integral part of another
process unit. These omission factors should be applied to each such conveyor
transfer point and should be based on the amount of material transferred
through that point.
The emission factors for material handling can also be applied to final
product loading for shipment. Again, these factors should be applied to
each transfer point, ore dump or other point where material is allowed to
fall freely.
Test data collected in the mineral processing industries indicate that
the moisture content of ore can have a significant effect on emissions from
several process operations. High moistjre generally redur.es thp uncon-
trolled emission rates, and separate emission rates art: provided for primary
crushers, secondary crushers,, tertiary crushers, and material handling and
transfer operations that process high moisture ore. Drying and dry grinding
operations ara assumed to produce or to involve only low moisture material.
For most metallic minerals covered In this Section, high moisture ore
is defined as ore whose moisture content, as measured at the primary crasher
inlet or at the mine, is 4 weight percent or greater. Ore defined as high
moist-ire at the primary crusher is presumed to be nigh moisture ore at any
subsequent operation for which high moisture factors are provided, unless a
drying operation precedes the operation under consideration. Ore is defined
as low moisture when a drver pre-otdes the operation under consideration or
when the ore moisture at the mine or primary crusher is less than 4 weight
percent.
Separate factors are provided fo~ bauxite handling operations, in that
eorae types of bauxite with a moisture content as high as 15 Lo 18 weight
percent can still produce relatively high emissions during material handling
8/82 Mineral Products Industry 8.23-3
-------
TABLE b.23-1. UNCONTROLLED PARTICULATE EMISSION FACTOR? FOR METALLIC MINERAL PROCESSES'
§
O
•z
p
O
Low aolstnre ore
Process
Crushing
Prlaary
Secondary
Tertiary
Emissions
kg/Mg (Ib/t-xi)
0
0
1
.2
.6
.4
(0.
(1.
(2.
5)
2)
7)
Particular paliaiuiia
< 10 Ul
U/MR (lb/ton)
0.02 (0.05)
NA
0.08 (0.16)
Nigh noist'.ire ore
Emissions
V^/Mfi (It/ ton)
0.01 (0.02)
O.Oj (0.05)
0.03 (0.06)
Particular emlssior.g
< 10 in
kg/Ng (Ib/'ton)
0
0
0
.004
.012
.001
(0
(0
(0
.009)
.02)
.02)
Knlsnlon
Factor
Rating
C
D
E
Wet grinding Negligible
Dry grinding
With air cor /eying and/or air
clasatHcat'on 14.4 (28.8)
Without air conveying or air
classification 1.2 (2.4)
1.3.0 ?6.0)
0.16 (0.31)
Negligible
d
d
Drying"
Ail ainerals but titanium,'
Tlrconlun sands
Tltar.luB/zlrconiua with
cyclones
Material handling and trans IT
All nlncialtt buc bauxite
Ba'utlte/aluaUna
9.8 (19,7)
0.3 (0.5)
0.06 (0.12)
0.6 (1.1)
5.9 (12.0)
HA
0.03 (0.06)
NA
e e C
e €- C
0.005 (0.01) 0.002 (0.006) C
NA NA C
00
"J
References 9-12. Controlled partlculate emiia^oa factors are diacuaaed In Section 8.23.3. NA - not available.
Defined In Section 8.23.2.
.Based on weight of auttrrlal entering prlawry crusher.
Based on weight of material entering grinder. Factors are the saae for both high anl.sture and low moisture nies. because naterial is
usually dried before entering grinder.
eBased on weight of oarerlal exiting dryer. Factors are the saae for both high w>latur<> and low moisture orcn. SOx emissions are fuel
dependent (see Cliapter 1). NO* emissions depend on burner design, conbuatlon tenparatiire, etc. (nee Chapter 1).
Based on weight nf material transferred. Applies to each loading or unloading operation and to each conwyor belt transfer point.
^Bauxite with ooisture content as hi^b as 15 - 181 can exhibit the evlaaion characterlatlea of low anlature ore. Use low •oisture
factor for bauxite unless material exhibits obvious stick-, nondlisting charrcterlatlcs-
-------
procedures. These emissions cf moderate to hi^h
uncontrolled emission rates ot typical dry oro facilities, this Invel of
8/62 Mineral Products InfUisfy K.."'.3-S
-------
controlled emissions represents greater than 99 percent removal of partic-
ulars emissions. Because baghouses reduce emissions to a relatively constant
outlet concentration, percentage emission reductions would be less for
baghoiuied on facilities with a low level of uncontrolled emissions.
References for Section 8.23
1, D. Kram, "Modern Mineral Processing: Drying, Calcining and Agglo-
Betc.tion", Engineering and Mining Journal. 181(6);134-151, June 1900.
2. A. Lynch, Minera 1 Crushing an d G rinding C jrr.u 11s, Elsevier Scientific
Publishing Company, New York 1977.
3. "Modern Mineral Processing: Grinding", Engineering, and Mining Journal,
181.(161) :106-113, June 1980.
4. L. Mollick, "Modern Mineral Processing: Crushing", Engineering and
Mining Journal. JLkl(6):96-103, June 1980.
5. R. H. Perry, et al.. Chemical Engineer's Handbook. 4th Ed, McGraw-Hill,
New York, 1963.
6. R. Richards and C. Locke, Textbookof Ore Dressing, McGraw-Hill, New
York, 1940.
7. "Modern Mineral Processing: Air and Water Pollution Controls",
Engineering and Mining Journal, 181(6) ; 1.56-171. June 1980.
8. W. E. Horst and R. C. Enochs. "Modern Mineral Processing: Instru-
ments'- ion and Process Control", Engineering and Mining Journal.
_18JL(6):70-92, June 1980.
3. MetallicMineral Processing Plants - Background Information for Proposed
Standards (Draft). EPA Contract No. 68-02-3063, THW, Research Trl&ngle
Park, NC, 1981.
10. Telephone communication between E. C. Monnig, TRW Environmental
Division, and R. Beale, Associated Minerals, Inc., May 17, 1982.
11. Written communication .^rom W. R. Chalker, DuPont, Inc., to S. T. Gaffe,
U. S. Environmental Protection Agency, Research Triangle Park, NC,
December 21, 1981.
12. Written communication from P. H. Fournet, Kai-.er Aluminum and Chemical
Corporation, to S. T. Cuffe, U. S. Environmental Trotection Agency,
Reaearch Triangle Park, NC, March 5, 1982.
8.23-6 EMISSION FACTORS 9/82
-------
8.24 WESTF.RN SURFACE COAL MIKIKG
8.24.1 General1
There are 12 major coal fields in the western states (excluding the
Pacific Coast and Alaskan fields), as shown in Figure ft.24-1. Together,
they account for more than 64 percent of the surface minable coal reserves
COAL
LIGNITE
SUB31 TUMI NOUS CZ3
BITUMINOUS ma
2
J
4
5
6
7
a
9
10
11
12
Coal tltld
Fort t'nion
Povdar River
North Central
Bighorn 3»iin
Wind Rivet
titan Fork
Ulnca
Southwticiirn .c«h
Sari Juan Hiver
Raton Hmmt
Ciein [s
Scrlpptbl* rutrvii
(1C6 ton»)
23.329
56,727
All underground
All underground
1,000
JOS
224
y.,3'L»
All vnderground
All underground
2,120
5/83
Figure 8.24-1. Co;>l fields 01 the western U.S.3
Mineral Products Industry
8.24-1
-------
in the United States.^ The 12 coil fields have varying character ist ics
which may influence fugitive dust emisblon rct,-s from inning operations,
including overburden arid coal seam thicknesses anJ structure, mining equip-
ment, operating procedures, terrain, vegetation, precipitation and surface
moisture, wind speeds and temperatures. The opr-rai inns at a typical west-
ern surface mine are shown in Figure 8.24-2 All operations that involve
movement of soil, coal, or cqui|_:>ieut, or exposure of erodible surfaces,
generate, some amount of fugitive
-------
Ul
CD
n>
n
o
0.
O.
c
in
To Prppntalloa
Sliipplnri
Figure 8.24-2. Operations ar typical western surface coal mines.
-------
TABLE S.2<*-1. EMISSION FACTOR EQUATIONS FOR UNCONTROLLED OPEN DUST SOURCLS AT
WESTERN SURFACE COAL MINES (METRIC UNITS)a
9
M
I/I
M
O
f-f
•n
n
0
70
CO
-il
Or.r.ti... N.l.rl.1 tain.ion. by p.rtlcle .!» r...r (...rodr.-.ic di-eter)b'C .__ ^"f^
TSP (< - 31 |«) < 15 \m
144 '
Truck losing Co.l -*4S L.9»»
fll)1"' (N)0'1*
PnlMnTin™ r». I 35.6 (•) ' 1.44 (•)
(HI1'3 (Hi1 *
Overburdro 2JJTJT^ °^> 4'^-
(N)'-3 (H)1 *
Dr.Rlinc Ovrrburdcn ° °°'6 (d>' ' 0'00" (")0 '
Srrappr* 16 . I0"6 (»)I-3 (W)2'* 2.2 • III"' (•;''* (W)2
(trivel Mode)
Grading 0.0034 (S)2'5 O.OOS6 (S)2 "
Vehicle tr.fflr 1-41= ^^j
(light/Mitiiu duty) (N) (n) J
i:»nl tnirk* O.OOH (M)'''* (L)0'* 0.0014 (n)3-5
(wind croaiou and
a
b T^o1^' "*' " tr* ""*' '^T . ""cle "' "•"••r." ir»»« ft. H» not avallwlc.
A = are bliatrd (•') d = drop height (•)
N = Bit ii-1 Boislure content (1> V = mtin vehicle Height (rig)
£ = hoi
-------
oo
U)
TABL'i 8.24-2. EMISSION FACTOR EQUATIONS FOR UNCONTROLLED OPEN DUST SOURCES AT
WESTER*: SURFACE COAL MINES (ENGLISH UNITS)a
0 vration
hatprial
Eniisinna hy_p«_rUclr _£J«_j(«n|
TSP (< - 30 j») < IS
.h.i
2.S PI./TSI1'1
ItflilS
\m i c l« on
Farlor
bU :ting
Track loading
foil oi
overburden
Coir.
ID)' "
1.16
Ib/bl.sl
!b/T
3
n>
i
I
Draftline
Scrapprs
(l nvrl mnilt)
Vehiclr traffic
cre)(hrT
' All rqilDtiDni arc liam RrlrrcncL ], c«rtpt for ro»l stniajr pilr rquatinn I ram Qeferrnce * TSP - tolnl ci.cppnilril parllrillitr VMT -
. vehicle ailva Iraveled. ^ITT = vehicle kilometers traveled. NA - not ''ailable.
TSF dllMLti vtut IE Brabuied ly a Blamljn' high voliKr sailer (srr Section 11.2)
Sy«bol8 for ei|UdtiOfis:
K - jrei blaited (ft2) d = drop hrighl (('.)
n - tvitfn and 8 2«-«).
-------
equations were developed throuxh field sampling various western surface
mint; types and are thus applicable to any of the surface coal mines located
in the western United States.
In Tables 8.24-1 and 8.24-2, the assigned quality ratings apply within
the ranges of source conditions that were tested in developing the equa-
tions, given in Table 8.24-3. however, the equations are derated one let-
ter value (e.g., A to B) if applied to eastern surface coal mines.
TABLE 8.24-3.
TYPICAL VALUES FOR CORRECTION FACTORS APPLICABLE TO THE
PREDICTIVE EMISSION FACTOR EQUATIONS3
Source
Blasting
Coal loading
Bulldozers
Coal
Overburden
Dragline
Scraper
Gmder
Light/medium
duty vehicles
Haul truck
Correction Number
factor of test
samples
Moisture
Depth
Area
Moisture
Moisture
Silt
Moisture
Silt
Drop Distance
Moisture
Silt
'Veighc
Speed
Moistwe
Wheels
Silt loading
5
18
18
7
3
3
8
/
19
7
10
15
7
7
29
26
Range
7.2
6
20
90
1,000
6.6
4.0
6.0
2.2
3-8
1.5
5
0.2
7.2
33
36
8.0
5.0
0.9
6.1
3.8
34
- 38
- 41
- 135
- 9.UOO
- 100,000
- 38
-22.0
• 11.3
- 16.8
- '.5.1
- '30
- 100
- 16.3
-25.2
- 64
- 70
- 19.0
- 11.8
- 1.7
- 10.0
- 254
- 2,270
Geometric
mean Units
17.2
7.9
25.9
1,800
19,000
17.8
10.4
8.6
7.9
6.9
8.6
28.1
3.2
16.4
48.8
53.8
11.4
7. 1
1,2
R.i
40.8
364
%
m
ft
m2
ft2
%
I
I
%
%
m
ft
I
%
Mg
'.OPS
kph
mph
%
number
g/m2
Ib/acre
Reference 1.
In using the equations to estimate emissions from sources in a spe-
cific western surface coal mine, it is necessary that reliable values for
correction parameters be deterir.i.neu for the specific sources of interest,
jf the assigned quality ratings of thf» equations are to apply. For exam-
ple, actual silt content of coal cr overburden measured at a facility
8.24-6
EMISSION FACTORS
5/83
-------
should be used instead of estimated values. In the event than site spe-
cific values for correction parameters cannot he obtained, the appropriate
geometric rrean values from Table 8.24-3 may be used, but the ^ssigner1 qual-
ity rating of each emission lactor equation is reduced by one level (e.g.,
A to B).
Kraisslon factors for open dust sources uot covered 3 a Table 8.24-3 are
in Table 8.24-4. These factors were determined through source testing at
various western coal mines.
The factors it; Table fi.24-4 for mine locations 1 through V were devel-
oped for specific geographical areas. Tables 8.24-5 and 8.24-6 present
characteristics of each of these mines (areas). A "mine specific" emist.on
factor should be usf-d only if the characteristics of the mine for which an
emissions estimate is needed art- very similar to those of the mine for
which the emission factor was developed. The other (nonspecific) emission
factors weie developed at a variety of mine types and thus are applicable
To any western surface coal mine.
As an alternative to the single valued emission factors given in Table
8.24-4 for train or truck loading and for truck or scraper unloadng, two
empirically derived emission factor equations are presented in Section
11.2.3 of this document. Each equation was developed for a source opera-
tion (i.e., batch drop and continuous drop, respectively), comprising a
single dust generating mechanism which crosses industry linos.
Because the predictive equations allow emission factor adjustment to
specific SOUK e ccmditi ons, i-lie equations should be used in place oi the
factors in Table 8.24-4 for the sources identified above, if emission esti-
mates for a specific western surface coal mine are needeo. However, the
generally higher quality ratings assigned to the equations are applicable
only if 1) reliable values of correction varameters have been deteimined
for the specific sources of interest ana 2} the correction parameter valuer
lie within the ranges tested in developing the equations. Table 8.24-3
lists measured properties of aggregate nititc.'ials which can be used to esti-
mate ccrrection parameter values for the predictive emission facto equa-
tions in Chapter 1], in the event that site speciiic values are not avail-
able. Use of mean correction parameter values t' rom Table 8.24-3 ieduces
th'.' quality ratings of th." emission factor equations in Chapter 11 by one
Mineral I'roducts industry 3.24-7
-------
TABLE 8.24-4. UNCONTROLLED rV» * TICULATE EMISSION FACTORS FOR
OPEN DUST SOURCES AT WESTERN SURFACE COAL MINES
Sourer Material
TSP
HIBC rai..i<»
location' factor"
Dr 111T4 Ovarburdeo
to»l
Toptril removal by Topioil
•C'ip«r
''vf burdtp O»trburd«
•i»'.>«adin| aaiiiioc iaet^ri vert
tad (.24-2 preaent cha/actcrialici
Any 1.3
C 59
V 0.22
0.10
Any C.'io
0.029
IV C.44
0.22
Aav C.012
C.0060
V C.C37
C.01I
Any 0.011
0 OH
III 0.0002
0.0001
V C 002
o.ooi
IV 0.027
J OU
III 0.005
0.002
11 0 OJ3
C 010
I o.ou
0.0070
Ar," 0 . 066
0 033
V J.wl?
c.ro4
IV 0.04
o . o;
A „ 3e
0.85 ^
tpeci/iC iiiae iocationi
developed (Reference 4)
if eact 01 theiv ninct
EaiiaiioB
Uolti Factor
Ratui!
th/holt
M/bo.'r
R.'hple
kj/aalr
Ib/T
kf/H|
Ib/T
it/N|
Ib/T
k«/n§
Ib/T
k|/H|
U/T
k|/H|
lb/I
«•/««
Ib/T
ki/T
:b/T
•I/Hj
lb/T
kl/H|
>b/I
k|/r1|
10/T
k|/H|
Ib'T
kj/nj
Jb/T
»g/H.
1£>/T
k|/N|
T
(•cre)iyr)
nectar*} (jrr)
for which U>
B
B
E
t
E
E
D
D
C
C
C
C
0
1)
b
D
I
I
I
I
E
I
I
I
D
D
D
D
I
I
C
C
_
C
m
. Tkulea 8.24-4
bee tcit for
othar factor
'•
(fro- 8t£«r«nc« S txc«pt for ov«rburden d'.illicg fro* R«ftr«oc» 1) ran be
•pplitd tr any H*tL«rv furlice coal mine.
Total auiptadtd pinicul.tr .TSP) deo&vei vnn i, Beaturrd by • llir.t'aKd
voluM lUpler («tf Section 11.2).
Predictive aBmaion f»rtor «qu«iioBi. woieb fenerally provide BO re iccurjtr
eftljuLei of miailoni, are pr'smttJ io Chapter 11.
8.24-3
EMISSION FACTORS
5/83
-------
TABLE 8.24-5. CtMEKAL CHAHALTERIST1CS OF SUi'.FACK CGrtL MINES REFKRRklD Tu IK TABLE
incral
•-o
.•f
c
n
"3 Industry
1
Type of
rtiuc Location coul Terrain
mined
1 N.W. Subbitiun. Moderately
Colorado steep
11 S W. SuhbitiiiD. berai rugged
III S.E. Subbltani. Gently roll-
Hontuiia ing ti>
semi ruggeii
IV Central Lignite Gently roll-
North Maktta iriK
V N.E. Suhbitiim. Flat to
rolling
cover
Moderate,
sagebrush
Sparse,
sagebrush
Sparse ,
moderate,
j: ' r ^ i r i e
Moderate ,
prairie
grassland
Sparse,
sagebrush
Surface soil
type and Mean wi.id Mean annual
erodibiii'y speed precipitation
index m/s niph CM in.
Clayey, 2-H 5.t 38 15
•oaay (71)
Arid soil *itH 6.0 13. A J6 14
cirf-y and
alkali or
carbonate
accunulation
(86)
Shallow cldy 4.8 10.7 28 - 41 11 - 16
loamy deposits
on bedrock
(47)
Loamy, loamy S.O 11.2 43 17
to sandy
(71)
Loamy, sandy, 6.0 13. 4 'J& 14
clayey, and
clay loamy
1102)
Reference 4.
I
-------
CD
ro
*-
TABLE 8.24-6.
OPERATING CHABACTERISTICS OF THE COAL MINES
REFERRED TO In iABLE 8.24-4a
tl
s
in
hH
O
z
^"1
>
n
-3
o
VI
rWomcler Required infsrnttlon
Production r»te Co.il mincJ
Coal transport Avg. unit train frequency
Strati griphir Overburden thickness
4ata Overburden density
Coal spun thicknesses
Parting thicknesses
Spoils bulking factor
Ai:ttvp pit (Ir^th
Coal analysis Moisture
rfata Ash
Sulfur
Heat content
Surface Total dictjrhed land
d'sp-^i'lon Active fit
Spoils
P.PC J » i nf d
Barren land
Associated dis^uuancei
Storage Capacity
Plastinfi Frequency, coal
Frequency, overburden
Area blasted, coal
Area blasted, overburden
Units
106 T/yr
p^r day
ft
lb/yd3
ft
ft
Jb
ft
I
J, vet
X, w.t
Btu/lb
• ere
acre
acre
acre
acre
acre
too
ner week
per week
ft2
ft*
I
1..3
NA
21
4000
9.3S
50
22
52
10
8
0.46
11000
168
34
57
100
-
12
NA
4
3
16000
20OOO
"if
5.0
NA
80
3/05
15. ^
15
24
liK)
13
10
0.59
963i
1030
202
326
2^1
30
186
HA
4
0.5
40000
_
III
l.'j
7.
9C
3000
27
S'
25
il'.
2\
a
(1.75
8628
21 '2
87
144
950
455
476
-
1
3
-
~
IV
3.8
NA
t>'j
-
2,4,8
32,16
20
an
38
7
0.65
8500
19/5
-
-
-
-
-
NA
7
NA
30000
NA
V
12.0b
2
:»5
-
70
NA
-
10!)
30
6
0.48
8020
L'17
71
100
ICO
-
46
48000
7h
7
-
~
. Reference 4. NA "^ not applicablt*. Dash -~ not
Kttimnle.
-------
References for Section 8.24
1. K. Axetell and C. Cowherd, Improved Emission Factors for Fugitive Dust
irom Wester. Surface Coal Mining Sources, 2 Volumes, EPA Contract No.
68-02-2924, U. S. Environmental Protection Agency, Cincinnati, OH,
July 1981.
2. Reserve Base of U. S. Coals by Sulfur Cor tent: Part 2, The Western
States, IC8693, Bureau of Mines, U. S. Department of tb'.' Interior,
Washington, DC, 1975.
3. Bituminous Coal andLignite Productionand Mine Operations -_ 1978,
DOE/EIA-0118(78), U. Si^DepartFieut of Energy> Washington","DC, June
1980.
4. K. Axetell, Survey of FugitiveDust from CoalMines, EPA-908/1-78-003,
U. S. Environmental Protection Agency, Denver. CO, February 1978.
5. LI. L. Shearer, et al. , Coal Mining Emission Factor Development and
Morieling Study, Amax loal Company, Carter Mining Company, Sunoco
Energy Development Company, Mobil Oil Corporation, and Atlantic
Richfield Company, Denver, CO, July 1981.
V83 Mineral Products Industry 8.2^-11
-------
PETROLEUM INDUSTRY
9.1 PETROLEUM REFINING1
9.1.1 General Deorripiion
The petroleum refining industry converls crude oil into more lhan 2500 refined products, including liujefied
petroleum gas, gasoline, kerosen.-, aviation fuel, diesel fuel, fue' c-ls, lubricating oils, an:i f.^ds'ocks for the
petrochemical industry. Petroleum refinery prlivities start with receipt of crude for storjge at the retinery,
include all petroleum handling and refining operations, and terminate with storage preparatory to shipping the
refined products from the rrfiihtry.
The petroleum refining industry employs a wide variety of processes. A lefinery's processing flow
scheme is largely determined by the composition of the r.rudr ci! feedstock and the chosen slate of petroleum
products. The example refinery flow scheme presented in Figure 9. 1-1 shows the general processing arrangement
used by refineries in the United States for major refinery processes. The arrangement of these processes will vary
among refineries, and ft w, if any, employ ->ll of these or /cesses Petroleum refining processes having direct
emission sources are presented in bold-line boxes on the figure.
Listed below are five categories of genera! ref:r-ry processes and associated o^rations:
]. Separation processes
a, atmospheric distillation
b. vacuum distillation
c. light ends recovery (gas processing)
2. Petroleum conversion processes
a. cracking (therrnu! and catulvtic)
b. reforming
c. alkylation
tj. polymerization
c. isomerization
f, coking
g. visbreaking
3. Fed oleum treating processes
a. hydrodesulturizalion
b. hydrotrealing
c. chemical sweetening
d. wcid Rat removal
e.
4. Feeds'ock and product
b.. s forage
c. 'c.iding
d. unloading
5. Ajxilia:'y .acilities
j hoilers
b. WdSleH'ate- treatment
c. hydrogen production
12 77 9.i-l
-------
fi.1-1. Schematic of an example integrated petroleum refinery.
-------
d. sulfur recovery plant
p. cooling towers
f, blowdown system
g compressor engines
Tht;se uttiiiery processes arn defined in the following section and their emission characteristics and applicable
emission control technology are discussed.
9.1.1.1. ^epnation Processes —The firs! phaee. in petroleum ref inmg opera lions is the separation of crude oil nto
its major constituents using three f> troleum separation processes: atmospheric distillation, variinni distillation,
and light ends recovery (gas processing). Crude nil consist-; of a mixture of hydrocarbon compounds including
paraffinic, naphthcmc, and aromatic hydrocarbons plus small amounts of impurities including sulfur, nitrogen,
oxygen and metals. Kefinery separation process*;* separate ilii-se crude oil constituents into common-boiling-
point tractions.
9.1.1.2. Conversion Processes—To meet :he demands for high-octane gasoline, jet fuel, and diesel fuel,
components ijch as residual oils, fuel oils, and light ends are converted' 10 gasolines and other light fractions.
Cracking, coking, and visbreaking pro^eMes are used to break large petroleum molecules into smaller petrole.jr,i
molecules. Polymerizatior nnd alkylation processes are used to combine small petroleum molecules into larger
ones. Isotnerization and reiorming processes are applied to rearrange the structure of petroleum molecules to
pro 1 uc;- higher-value molecules of a similar molecular size.
9.1.1.3. Treating Processes—Petroleum treating processes stabilize and upgrade petroleum products by
separating them from less desirable products and by removing objectionable elements. Undesirable elements
such as sulfur, nitrogen, and oxygen are removed by h)drudesulfiiri7.alioii,hydrotreating,chemicalsweetening
and m-j'i gas removal. Trcaliug processes employed primarily for the separation of petroleum products include
such processes as dea?phallin£. Debiting is used to reiyove sail, minerals, gril. and water from crude oil Iced
stocks prior to refining. Asphall bbwing if used for polymerizing and stabilizing asphalt to improve its weathering
characteristics.
".1 1.1. Feedstock and Product Handling—The refinery >odslocik and product handling operations consist of
unloading, ~l?rH£p blending, and loading activities.
9.1.1.5 Auxiliary Facilities—A wrle tt sort men I of processes and equipment no! dinjitl) iiivoKetl in :!ie refining
ul crude vil are used in fimctionr vital to the '.-peration ot the refinery. Examplr^arr boilers, waslewater trea:rrent
far.litii's, hydrogen plants, coolmp, towers, and sulfur recovery units. Products fnm auxiliary facilities (clean
water, sleam. and process heat) arc required by mo11 refinery pror*.-*-; units liiroughou! i\w rcfi.u'rv.
9.1.2 Process Fmission Sources and Control Tt-rhnoio^y
This section presents descriptions of those refining processes that are bipp.ificant air pollutant cuntribulors.
Krucoss flow schemes, emission characteristics ar^d emission control lerhnol »gy are discussed for each process
Table 9.1 J lisls the emission factors for direct proce.s.s emissions in petroleum rc.iineries. Tlie following process
"mission sources are discussed in this section on petroleum refining e.m
i. Vacuum distillation.
2. Catalytic cracldn^.
.'V Thermal cracking proci-ssas.
•1. luility Loil< rs.
r>. Heaters.
12/77 Pclroleiim Inriuslry 9.1-3
-------
6. Compressor engines.
Slowdown systems.
8. Sulfur recovery.
9.1.2,1. Vacuum Distillation — Topped crude withdrawn from the bottom of the atmospheric distillation culumn
is composed of high-boiling-point hydrocarbons. When distilled at atmosphere- pressures, the crude oil
decomposes and polymerizes to foul equipment To separate topped crude into components, it n>ij«! l*di>hi'rd m,i
vacuum column at a very low pressure and in a steam .Mmosphere.
In the vacui m distillation iiiiit, topped n ude i.i heated with a process healer to temperature:, ranging from
700 to BOOT (37'J to 425°C). The healed topped crude is flashed into a multi-tray vacuum jisnlialion column
operating at vacuum:: ranging from 0.5 to 2 psia (350 to 1400 k^/mz). In the vacuum column, the topped crude is
separated into ronimon-boiling- point fractions by vaporization and condensation Stripping steam is normally
injected iiitu the buttum uf the vacuum distillation column to assist in the separation by lowering ihe dftHlive
partial pressures of .he components Standard petroleum fractions withdrawn from the vacuum distillation
column include lube distillates, vacuum oil, asphalt stocks, arid residual oils. The vacuum in the vacuum
distillation rolumn is normally maintained hy the use cf steam ejectors h.U may he maintained by the. use of
vacuum pumps.
The major sources of atmospheric emissions from the vacuum Distillation column are associated with the
steam ejectors or vacuum pumps. A major portion of the vapors withdrawn from the column by the ejectors or
pumps are recovered in condensers. Historically, the noncondensable portion of the vapors has been vented to the
atmosphere from the condensers. There are approximately 50 pounds (23 kg) of noncondensable hydrocarbons
per 1000 Barrels of lopped crude processed in the vacuum distillat'on column. 2'I2.'J A second source of
atmospheric emissions from vacuum distillation columns is iir wasu h<-at
boilers. 2-:2llJ Thi-'se control technique^ ars- gene-ally greater than *W perci-nl efficient in liu control o'
hydrocarb- .1 emissions, but they a ho contribute, to the emission of combustion jirndur -t>.
9.1.2.2. Catalytic Crackin.;, — Catalytic cracking, using heat, pressure, and catalysis, converts hea>y °ils
lighter products with product distributions favoring the more valuable gasoline unJ distilUitc blending
components. Feedstocks are usually ^as oils (roni atmospheric distillation, vacuum distillation, i.'C-kirie, and
deasphalnng processes. These feedstocks typically have a boiling langr of 6SO to 1000° F (340 to S40° C) . Ail :-i the
cataiytic cracking processes in use today can be clarified as either flui.H:z»d-hfd or mr>ving-hed units
Fluidi zed-bed Catalytic Cracking f FCC) — The FCC process uses a catalyst in the form of very fine partii.! -s
thai art as a fluid when aerated with a vapor. Fresh feed is preheated in a process heater and introu'ui t-J iiitu tho
bottom o,' a vertical transfer line or riser with hot regenerated catalyst. The hot catalyst vaporizes the feed
bringing both to the desned reaction ltrn;per?.ture, WU.1 lu 980° FMfO tu F)l!.>° (,). Flic high ,n li\i'\ »: imnlrin
catalysts causes most of ihe cracking reactions to uke place in the ris^r :i^ the catalyst and oil rnixturi.* (luwi
• nward into the reactor. The Hydrocarbon vapors are *pavated from thu catalyst particles by cyclones n; the
reactor. The readier products are sent to a fractionator for separation.
9.'-4 EMISSION FACTORS 12/77
-------
The spent catalyst falls 10 ihr bottcm of the reactor and is steam stripped as it exists the resrlor bottom to
remove absorbed hydrocarbons. The spent catalyst is then conveyed to a regenerator. In thr regenerator, coke
deposited on the o.talyst as a result of the cracking reactions is burned off in a controlled combustion process with
preheditd air. Regeneiator temperature is usually J 100 to 1250° F (59C to6T5° C). The catalyst is then recycled to
be mixed with fresh hydrocarbon feer).
Moving-bed Catalytic Croc king (TCC) — In t he TCC process, catalyst beads (~ 0.5 cm) flow by gravity in to the
top of the reactor where they contact a mixed-pr-a.sf' hydrocarbon feed. Cricking reactions take place as the
catalyst and hydrocarbons move conr.urr«i,iiy downward through the reacior to a zone where the catalyst u
separated from the vapors. The famous reatvion products flow out of the reactor to the fractionation section of
the unit. The catalyst is steam stripped tr remove any adsorbed hv'!ic"arbc;::*. It then lulls ;nto the regenerator
where coke is burned from the catalyst with air. The regenerated catalyst ic sepjrated fror.'i the flue gases and
recycled to be mixed with fresh hydrocarbon feed. The operating temp';ra;ures of the reart-jr and regenerator in
the TCC process are comparable to thos° in the FCC process.
Air emissioii from catalytic cracking orocesses are (1) combustion proojcts from process heaters and (2)
flue gas from catalyst regenerati'7;j. En-:ssion* from process heaters are discus- *••! later in this section. Emissions
from the catalyst regenerator include hydrocarbons, oxides of sulfur, animc,..;a. aldehydes, oxides of nitrogen,
cyanides, carbon monoxide, ani particulates (Table 9.1-1). The paniculate emissions from FCCunitoare much
greater than those from TCC units because of the higher cataJyst circulation rates used.2lJ>i
FLC paniculate emissions lire controlled by cyclones and/ 01 electrostatic precipitates. Participate control
efficiencies are as high as 80 to 85 percent. *• ' Carbon monoxide wusteheal bnjlero reduce the carbun monoxide
and hydrocarbon emissions from FCC units to negligible levels.3 TCC catalyst regeneration produces similar
pollutants to FCC units but in much smaller quantities (Table 9. 1 -I). The pirticulate emissions from a TCC unit
are normally controlled by high-efficiency cyclones. Carbon monoxide and hydrocarbon emissions from i TCC
unit are incinerated to negligible levels by passing the flue gases 'h rough a process heater fire-box or .smoke plume
burner. In some installations, sulfur oxides are removed by passing the regenerator flue gases through a water or
caustic scrubber. M.^
9.1.2.3 Thermal Cracking — Thermal cracking processes include visbreakingand coking, which Freak heavy oil
molec lies by exposing them to high temperatures.
J tsbnaking — Topped crude or vacuum residuals are heated and thermally cracked (850 to^JK)0 F, 50 t
psig) (455 to 480° C, 3.5 to 17.6 kg/cm1) in the visbreaker furnace tr. reduce the viscosity or pour point of the
charge. The cracked products arc quenched with gas oil and flashed intoafractionator. The v?.por overhead from
tilt- fractionatui is separated into light distillate product . A hi-svy distillate recovered from the fractionator
liquid can br us-d as a furl oil blending component or tisrtl as catalytic cracking feed.
— Coking is a thermal cracking process used to c( nver i low value residual fuel oil to highe. value gas
oil ind petroleum roke. Vannim residuals and thermal tars art cocked in the coking prnress at high temperature
?.nd low pressure. Krndiicts are petroleum coke, gas oils, anr! iighier petroleum storks. Delayed r.okmgislhe most
widely used process today, but luid coking is expected to become an important process in the future
In the delayed coking process, heated charge stock is led into the bntom section of a Iractionalor where light
ends are stripped from the feed. The stripped feed is then combined with recycle products from i tit- coke drum and
rapidly heated in the coking heater lo a temperoture of 90T1 to 1 100° F (4flO to 590° C). Steam injec ion is used to
control the residence time in the heater. The vapor-liquid feed leaves the heater, passing to a coke u!rum where,
with ( oiitrolled residence time, pr* ssure (25 to 30 p^igj (] .8 to 2.1 kg/ cm2), and temfirtature (750° F) (.100° C), it
is cra< k"d to form coke apd vapors. Vapors from the drum return to the frartiotiator whert: the thermal Tracking
pr^dui.r.-. are r«-r.overed.
12/77 Petroleum Industry 9.1-3
-------
Table 9.1 1. EMISSION FACTORS FOR PETWOLEU* REFINERIES
14
— -—• •
\
Proems
Fuel Oil
F«>11CUI«BS
SuHur
I5» ictus
,'«5 S0j(
SMSCCI
Cwbon
monomd*
on 1.3 - FuolOti
Toil!
hydro
cobon**
Combyslian
NiSiJg«n <
o«.4a
(MN02)
AidittrcMc
*g
N itural r,m Sw Setl*" 1 4 - NMurat CM Commwtwn
r'njic c«tft*ylic rr'»cltifl(l units ft
Uncontrolled
b/IJW'iwntaM
leg* 'Si3 iiiers fre&fi f«*d
EtocVcnlillC pIKipiUltar
anfl CO Boiler
ib/ID3 by frisfl *td
kq;io' iftei* Irish toed
UM..^"^-*
ib/ltt* bbl 1n?<< >M<1
ng/10'litsra fresn food
Fluid colunj jrms '•
Unconlfollwl
Ib^tO^ 9fy fr^ah foed
hg/'ic^ Iilef9 frvsh foRii
El«ctr£»itttie pretipi^smr
nnrT CD .M3||M
1>/'1(>- bb Irrah foed
KP./IO- rt«»fr««.«.d
°*^~*"^™
1^/10' *t; ^as liurn«d
Kg/K fn1 9119 EMfr^NS
Ga^ turbines
lt,na'n'gmtn,"»a
^Wm-^ftur™^
Z42
(93 10 340J c
069S
10 2Sr to 0.»T6|
4Sa
1710 1W)
0171
(O.C20 to 0.428!
17
0043
&23
ISO
ess
U0196
NA
^
Neg
Hug
Nt,
493
;ioo 10 s?s)
1.413
(0 ?«i 10 1 SOS)
403
' TO 10 3JS)
!.4»3
(B 286 lo >50S)
6C
D.IM
NA'
NA
NA
NA
NA
2«k
3»
a
13,700
382
Hug*
**9
3 BOO
10 a
NA
NA
NSfl
hwq
NA
043
7.«
o,«z
1 t4
220
0630
Ntg
Nea
•7
ozso
NA
NA
Nog
N.,
NA
M
21 B
002
0.21
710
(37 1 10 145 01
0204
CO 10710041C1
71. 01
(37 1 19 !4S 0)
b.2O4
(8 107 in 0 416!
S
0014
NA
NA
NA
NA
N-
34
SS4
03
47
19
OOS4
l*i
IM?
12
UO34
NA
NA
NBg
H*l
NA
0 1
I S
N*
NA
54
OISi
N«9
Nog
S
0017
NA
NA
N«g
N*0
r-^
o;
3'
NA
NA
B
B
B
C
C
c
c
2
B
a
B
-------
Table 9.1-1. (Continued) EMISSION FACTORS FOR PETROLEUM REFINERIES
-1 * '
-1 '
BkMroown system* 1
Uncontreiled
In/103 bbJ refinery
tfMd
koylUJ liters refinery feed
k'ipor recovery system
and flaring
lb'lf> bbi refinery feed
kg.'iO" mers rafmery teed
Vacuum dutiaator ""
"fl
—T column cO'idonMTS
3^ Uncontrolled
_ It IP bbl rafinarv faad
2 kg/ 10' litara re'inery teed
3 Ib/iy bM vacuum laad
— kg/101 liters vjcuum faad
r^ Controlled
C
9B
JJ Cl*tt$ puini and t*il gnfl
2C.9
00(7
Nag
Nag
Sa>9 section 5 18
Cwnxi
Nag
N«
4.1
0012
Nag
Nag
Totll
hytfro-
CajlMNU
seo
vie?
o.a
0002
18
OOS2
50(0-110)
0.1<4
Nag
Nitrogen
oudn
Nag
Nag
18 «
DOS*
Nag
H
Moatiydas
Nag
Nag
Nag
Nag
Kto?
Nag
Nag
Nag
'
Am/norm
N««
r«g
r«ng
Nag
Mac
Nag
Nag
Nag
Nab
Err.owon
lac lor
ralmg
C
C
c
c
c
c
c
c,
c
Ov«r«T less thin i p,trc«nt by weiyht cri the total hydrocirtMin pfTmuom are
b Re1efenc« 2 (hioogh ft
Humbofa m paronthvsti indicate r«nge of values oCMArvad
Undw ihe New Source Perto-minca Sundards controlled FCC rageneraiors w II tia^e parttculate emm
Neglfgtf>le em us ton.
May be Higher due to the com bus) on of imrr HI*
^ flafefonc* 2
h R*rf»r«oc« s
1 MA. »*M Avattabia
' Rbferencas 3, 10
s ' M^insry gas sulfur conrem fib/1000 *t*) Factor* basad en i10pflrc«>ii rombuit*on of .wMur to SO.»
xn kmw than 19 ib/io* MX f'eth feed
r> Rofarancai ! 12. 13
-------
In the fiuid coking process, typified by Hexicokmg, rt».idiiai oil feed^ ore injected into ihe reactor wrier;; ihev
are thernwlh cracked. yielding cuke and a vide range or vapor jiroduds. Vapors leave the rraeior and are
quenched in a. srnibber where .-nl ruined coke fnu'sare removed, The vapors are then fracli onu led Coke from I he
reactor enters,.., heater .-ml is dr NuIali'.'Zed. The voi.ililr* from liiu healer are treatt'd fur fines and sullur removal
In yi^ld a partieulale free, low-sulfur fuel gas. The defolatiliscd cok. is cir< ulalt-d iroin (lie In aler to a easifier
where 95 per«)n» ot the reactor uikr i- gasified at high temperature viith steam and air ur oxygon. The gaseous
products ar.J . oki from thn ga.-ilie.' are returned lu ihe liculrr lo supply heal fur the devoljlilitatinn. I i:frsegas( s
exit thf heater will the heater volatile1* through ihe same line?- unit si.Hur retri'.ival prorrsses.
From available literature. M is unclear v,hut t miviniis an rrl. •<•.(•simi.i. Kn'-is.iion!- from the proces> heaters ^re
dist -issed later in (hi;, section, tu^ttive I'inisMuiis from mi>rellum''.'.i> leak- jre bijfiiifieaiit hecaute of the high
ti^iiiperalures in\u|ved. and are depende it ,'puii n|uipnie!il t>|i'' and i uni Duration, optT?ling comlilions, and
general •nainte.nanc.i* piaclirrn. r'!g«!i\e rm^sions ai<- ahi> di.se ii^seti Ijter in this ?ef tlfin. Part ieulali: emissions
from dela ed coking opt rationsarepoleiiliall" very sign if Iran1. These emissions arnas^ocialed with remoi'in^ the
coke from 'he coke drum and substtjuiTt haiv.iling and storagi- operations. Hydrocarhon emi3sions are also
associated w.'th coo I i ox and venting the coke drum prior Ic coke removal. However, comprehensive data for
delayed coking emission i have not been included in availuble literature. 4v
collecting coke druid ein.ssions in an enclosed syslem and routing th^m lo i refinery flare 4>s
9.1.2.4 Utilities Planl — The utilities plant supplies the 'leamneressarv tcr the refinery. Although thj steam ca ,
be used ;o produce, electricity h\ ihrolthng through a tiirhine, it is primarily used tor heating jnd separating
hydrocarbon streams. When used for heating, ihe steam usually heats the petroleum indirectly in h»at
exchangers L(iid reium* to the boiler. In direct contact operations, the sieam '-an serve as a stripping medium or a
process fluid Steam may also be used in vacuum ejectors tu produce a vacuum Emissions from boiler? and
applicable emission control technology are disru.ssed in much greater detail in Chapter 1,0.
9.1.2.5 Sulfur Reivvery Plant - Sulliir recovery plants arc used in pL-troleum 'efiiieries to convert hydrogen
bulfide (HjS) scpa:u'ed from refintrrv gas streams into tne mon disposable bv-pioduct, ?lenierital .sulfur.
from siiliur recovery plants aiid their control are disiusseiJ in Section S.iH.
9.1 .2.ii Blo'.vdown Sy.-.ten. — 1 he blowdown system |irovi<1'S for the ' iff ilispri.- il of hyrirorarbon« (vapor and
liqu'd) ili^'-hargod irom prissure rthcf devices.
Most refining pro--essing iinils and equipment subi- :«:i to ph'.rmcd ur unplanned hyd.ocaiLun discharges are
manifolded into a ceil lee; ion un: I, railed the hiowdo«vn vvvti-r«i I!' using a s*-ric.-, of flash drurn= and condensers
arranged in uerreaMng prrvsure, the bluwdowu is se;, ..rated into vapor and licjuid cuts. The separated liquid is
rsrycled into the rerincry Tl.« ^.iseotis ruts can i-ittur he smokclrNsly Hareil or rei'>(tied
l.ncornro!!«'d hlowilowri emi>sions primarily < f>n»i:,t of hydro<-.i.-ln.n.-, bi.t < an al.'-o include ;inv of the other
« :'ti:ria pollul-inth. 1 tie eniission rale in a |i!ov;down >> stern is f Uinctioi; of the amount of ctjuipmcnl manifolded
into the system, 'he frequence of equipment discharges, and ihe blowdown system uontrols.
FmissKins from 1 he blrwdown system i Jn lu-t Uei-livelvi imlndled b', coinliiistiriri of I he iKio •
a flar To obtain rompleti" conihu^lio'i or smokeless I, liming (^ icf)inrpi1 by most stales) . sleam is injcrled in the
combustion zone of the fiar<' lo provide turlmlcru e and to uispiralc .ur. Si cam injertuin also reduce- emissions of
nitrfjpen oxides by lower ing the flame ternperal-irt-. (iontrr.lled <• mis.- ion A an- li.-.tcd in Table ') .'• . -I.-'- '
KMI-SSION FACTORS 12/
-------
9.1.2.7 Process Heaters - Process heaters (furnaces) are used
extensively In refineries to supply the heat necessary to raise tht
temperature of feeu materials to reaction or distillation level. They
are designed to raise petroleum fluid terape rat-ires to a maximum of about
950°F (5iOeC). The fual burned may be refinery gas, natural gas, residual
fuel oils, or combination", depending on economics, operating conditions
and emission lequirements. Process heaters may also use carbon monoxide-
rlch recent-rater flue gas. as fuel.
Ail the criteria pollutants are emitted from procetss heaters. The
quantity of these emissions is a function of the type of fuel burned,
the nature of che contaminants in the feel, and the heat duty of the
furnace. Sulfur oxide c?:i be controlled by fuel desulfurination or flue
gas treatment. Carbon monoxide and hydrocarbons can be limited by more
combustion efficiency. Currently, four ^eneinl techniques or modifi-
cations for the control of nitrogen oxidas are r.e-'n" Investigated;
combustion modification, fuel modification, furnace design and flue gas
treatment. Several of these techniques are presently buinp applied to
large utility boilers, but theii applicability to procsss heaters ha?
not been established.2* 1't
9.1.2.8 Compressor Engine? - Many older refineries run high pressure
compressors with reciprocating and gas turbine engines fired with natural
gas. Natural gas has usually been a cheap, abundant source of energy.
Examples of refining units operating at high pressure include hydro-
desulfurization, isomerisatlon, reforming and hydrocracking. Internal
combustion engines are less reliable and harder to maintain '_han steam
engines or elective motors. For this; reason, and because of increasing
natural gas costs, very Tew such units have been installed in the last
feu years.
The major source of emission?; from compressor engines is combustion
products in the exhaust gas. These omissions include carbon monoxide,
hydrocarbons, nitrogen oxides, aldehydes and ammonia. Sulfur oxides may
also be present, depending on the sulfur jr.nteut of the natural gas.
All these emissions -ire significantly higher in exhaust of reciprocating
engines than from rurbinc engines.
The major emission ctntrol technique applied to compressor engines
it, carburetion adjustment similar to that applied on automoniles.
Catalyst systems .similar to those applied to automoV les may also be
effective in reducing eiuissions, but their us2 has not been reported.
9.1.2.9 Sweetening - Sweetening of distillates is accomplished by the
conversion of tr.errnpf-anr, to alky! bisulfides in r'ne presence of a
catalyst. Conversion may be followed by an extraction step for thf
removal of the alkyl di.ru1 fi^.es. In the conversion process, sulfur is
added to thf1 sr.ui. distillate with a small amount of caustic and aiv.
The mixture is tiv.-n pasted upward through a fixed bed catalyst counter
to .T flow of caustic entering at the top of the vcrscl. In the conversion
and extraction process, the sour distillate is wasl.cd -?ith caustic: and
then i'j contacted in the extractor witii a solution of catalyst and
j 0/80 I'ecvo' cuii Industry 9.1-9
-------
Table 9.1-2. FUGITIVE EMISSION FACTORS FOR PETROLEUM REFINERIES*
Sourer screta Factor i.tu >;ur M .% ^ Cotitr-:! let jpplK-jbltr U"ur''
Typ« Unlit tniii' >tibC •-• ------
Plpcllre v,ilv«i M l*j/hr-iourr« O.OSl (ri.nln - .".SIM NA MaM-orlng and ^airurp.irue nn i:. fv;
kj/jay-bjun« 'J.fci P.): - I. IS.
II! " - •'1i ll). C" 7 - C.O M *A
0.26 (0.18 - 0, )*)
j.OH co.no7
•) '••'.•'! -.1.001" ').';!'•) SA :rkl.l!ljtl -n .( .-.•;• "' ph.?. .- -o, n >-..!
NA *i : i
011 - i in
0.07< lO.'iD - O..OI ?(,» Crap-, juJ
a. ?i, ('i ;s - 2 :•'
Pm»ur« vtt.,1 H " c.lt (I.,') - ; j! NenllBlb'.c- fuptj,-.- .!,•;»> un.t
relief Vulve^ '' 1.9 \..\ - U, vjlvri onc/r: vi-i
Coollni lw«ri - lo/JO' J-1 tf l.ns
WAC«r ' 0.7C Min. :-ii7jt iov. o;' hydru(
Irtf otli-.n w..t.t .
n! i:t.s.*I Infl w.tt.rr fm
V|/10* 1J rers raclinn
water ".7 3 OBJ
lh/10- bbl rtfineiy
ref 1 nc ry f e.'J
lb'10' »•! waitcvacvr
lb/ O3 tbl refincrv
Loading hf« S«^'1flp t.-
* Data fri/ Htf«firiLti 2, *, 1* and 13 i^cspc a-. not*ij. "v*rjK, U-s* t^it.
NA • Sot Available.
The mean id«nt'. {ivat It-n TuownU ind (rou. n^i.ikt «nJ ccs:rip: iors Jrc
Id«nt«,f icatior Str*arj
NuncraJ Name S:ri .7; Croup De^|•^ic: ioi:
Alt fltr«B»K A'.! srr
Qas itr««m: Hv're;a
Lltfht liquid and
f,*-Wilcji.^ atre
^iquU' 5:r'-ri t:th o vjpor pr«5?.ir* *.TJ«I l > ^r U-?s fh.-" ^>af ^.! '-pr,^..
ysla ' ")j" • .i' 68^ f.i .'' !3"C), based on ihr ??W8( v-la1,!!*- .I.iib p:tser=
frun Rvfcrvnc* \'
t - -ill i i It
lacti>[ > or r» ' 14. * vulvas In jtik >erv'if ^ s t.
-------
caustic. The extracted distillate Is then contacted with air to convert
nercaptans to disulfides. After oxidation, the distillate is settled,
inhibitors are added, and the distillate is s^nt to storage. Regeneration
is accomplished by mixing caustic from the bottom of the extractor with
air and Chen separating the disulfides and excess air-
Th« major emission problem is hydrccarbcns from contact between
thu distillate product and air in the "air blowing" step. These emissions
are related to equipment type and configuration, as well as to operating
conditions and maintenance practices, **
9.1.2.10 Asphalt Blowing - The asphalt blowing process polymerizes
asphalcic residual oils by oxidaticn, increasing their melting temper-
ature and hardness to achieve an increased resistance to weathering.
The oils, containing a large quantity of polycyclic aromatic compounds
(asphaltic oils), are oxidized by blowing heated air through 3 heated
batch mixture or, in continuous process, by passing hot air counter-
current to the oil flow. The reaction is exothermic, and quench steam
is someLimes needed for temperature control. In some cases, ferric
chloride or phosphorus pentoxlde is used as a catalyst to increase the
reaction rate and to impart special characteristics to the asphalt.
Air emissions from aophalt Mowing are primarily hvdrocarbon vapors
vented with che blowing air. The quantities of emissions are small
because of the prior removal of volatile hydrocarbons in the distilla-
tion units, but the emissions may contain hazardous polynuclear crganlcs.
Emission ate 60 pounds per ton of asphalt.^3 Emissions from asphalt
blowing can be controlled to negligible levels by vapor scrubbing,
incineration, or bothL»13
9.1.3 Fugitive Emissions and Controls
Fugitive emission sources ate gtnerally defined as volatile organic
compound (VOC) emission sources not associated with a specific process
but scattered throughout the refinery. Fugitive emission sources
include valves of all types, flanges, pump and compressor seals, process
drains, cooling towers, and oil/water separators. Fugitive VOC emissions
are attributable to the evaporation of leaked or spilled petroleum
liquids and gases Normally, control of fugitive emissions involves
minimizing leaks and op.*l.ls through equipment changes, procedure changes,
and improved monitoring, housekeeping and maintenance practices.
Controlled and uncontrolled fugitive emission factors for tht-< following
sources are listed in Table 9.1-2.
0 valves (pipeline, open ended, vessel relief)
0 flanges
0 seals (pump,
-------
9.J.3.'. V.» 1 ws , Fl.'in^.i's, Sr;ils ;niil l)r:ilns - Knr ( lirric .•:inir«-<<::, ,'i very
hlph I'orroli'iL Ion i;;is horn tUnnil lu'lwi-en in;is;» cm I si Ion mir:; ;mtl (In- ly|>«'
of sLre.im scrvlfi* In which the simrces ;iri- eir.pl oyi.-30,COO barrels
(52,500 m3) per day is esffiratpd as 45,000 pounds (20.4 MT) per day.
See Table 9.1-3
9.1.3.2 Storage - All refineries have a feedstock and product storage
area, termed a "tank farV', which provides surge storage capacity to
assure smooth, uninterrupted refinery operations. Individual storage
rank capacities range from less than 1000 barrels to norf. than 300,000
barrels (160 - 79,500 m^). Storage tank designs, emissions and emission
control technologies are discussed in detail in Section 4.3.
9.1.3.3 Transfer Operations - Although most refinery feecitucks and
products are transported by pipeline, some are transported by trucks,
rail cars and marine vessels. 'Chey are transferred ro and from these.
trnrsport vehicles in the refinery tank farm area by specialized pumps
an-1 piping systems. The emissions from transfer operations and appli-
cable emission control technology HI a discussed in much greater detail
in Section '1.4.
9.1.3.4 Wastewater Treatment Plant - All refineries emplcy some form of
wastewater treatment so water effluents can safely be returned to the
environment or reused in the refinery. The design of wastewater treat-
ment plants is con-plicated by the diversity of refiner'1' pr°.lulants,
i'v.-.luding oil , phenols, sulfides, dissolved solids, arn tcxic chemicals.
Although the waste-water treatment processes employed by refineries vary
greatly, they generally include neutralizfers, oil/wa^ei separators,
settling chambers, c'arifiers, dissolved air flotation systems, coagu-
lators, aerated lagoons, and activated sludge ponds. Refinery water
effluents are collected from various processing units and are conveyed
through sewe^^ and ditches to the wastewcter treatment plant. Most of
the wastewator treatment occurs in oper ponds and tanks.
9.1-12 EMISSION FACTORS 10/80
-------
The main components of atmospheric emissions from wastewater treat-
ment plants are fugitive. VOC and dissolved gases that evaporate from the
surfaces of wastewater residing in open process drains, wastewater
separators, and wastewattr ponds (Table 9.1-2). Treatment processes
that Involve extensive contact of wastewater and air, such as aeration
ponds and dissolved air flotation, have an ever greatei potential for
atmospheric emissions.
The control of wastewntor treatment plant emissions involves cov-
ering waptewater systems where emission generation is preat^st (such as
covering .American Petroleum Ins'itute separators and settling basins)
and removing dissolved gases from wastewater streams with sour water
strippers and phenol recovery units prior to ti»*ir contact with the
atmosphere. These control techniques potentially ran achieve preater
than 90 percent reduction of wastewater system emissions.13
TABLE 9.1-3. FUGITIVE VOC EMISSIONS F.ROM AN OIL REFINERY17
. - - - __
Source
Valves
Flanges
Pump Seals
Compressors,
Relief Valves
Drains
Cooling Towert.
uil/Waccr Separators
(uncovered)
TOTAL
Number
11,500
46,500
350
70
100
650
-
-
VOC
Ib/day
6,800
600
1,300
1,100
500
1,000
1,600
32,100
45,000
Emissions
kg/ day
1,084
272
590
499
227
4i4
726
14,558
20,408
Emissions frnn the cooling towers and oil/water separator.'.' are based on
limited d^ita. EPA is currently involved Jn further research to provide
hettei .l.ita on wastewater system 'Jup.itlve emissions.
9.1.3.5 Coclir.R Towers - Cooling towers arc used extensively in refinery
cooling ^ater systems to transfer waste heat from the cooling water to
che atmosphere*. The «;.i:ly refineries not employing cooling to'reis are
tliose with once-through cooling. The increasing scarcity ot large vater
supplies required foi oncft-throufjh cooling is contributing to the disappear-
ance of that form of -P.finery cooling. In the roolinj; uowcr, warm
cooling water returning from refinery processes is contacted with air by
cascading through packing. L'oolir.g water circulation rates for refineries
commonly range, from 0.3 to 3.0 gallons (1.1 - 11.0 liters) per minute
per barrel per day of refinery capacity. »•"
Atmospheric emissions from the cooling tower consist of i^gitive
VOC and gases stripped frora the cooling water as the air and water come
into contact. These contaminants enter the cycling water system from
10/80 Petroleum Industry 9.1-13
-------
leaking heat exchangers and condensers. Although the predominant conta-
minant In cooling water is VOC, dissolved gases such as hydrogen sulflde
and ammonia may also be found (Table 9.1-2) ,2.1+» J 7
Control of cooling tower emissions Is accomplished by reducing
contamination of cooling water through the proper maintenance of heat
exchangers and condensers. The effectiveness of cooling tower controls
is highly variable, depending on refinery configuration an^ existing
maintenance practices.4
References for Section 9.1
1. C. E. Burklin, et al. , Revision of Emission Factors for Petroleum
Refining. EPA-450/3-77-030, U.S. Environmental Protection Agency,
Research Triangle Park, NC, Ocfober 1977.
2 . Atmospheric Emissions from Petroleum Refijieriea; A Guide for Measure-
ment arid Control, PHS No. 763, PuMIc Health Service, U.S. Depart-
ment of Health, Education and Welfare, Washington, DC, 1960.
3 . Background Information for Proposed New Source Standards; Asphalt
Concrete Plant'}, Petroleum Refineries^ i .orage Vessels, Secondary
Lead Smelters and Refineries, Brass or Bronze Ingot Production Plants,
Iron and Steel Plants, Sewage Treatment Plants, APTD-1352*, U.S.
Environmental Protection Agency, Research Triangle Pprk, NC, 1973.
4. John A, Daniel son fed.), Air Pollution Engineering Manual (2nd Ed.),
AP-40, U.S. Environmental Prote tion Agency, Resean.h Triangle
Parl-., NC, 1°<73. Out of Print.
5. Ben G. Jones, "Refinary Improves Particulete Control", Oil and Gas
Journal, 69(26) ;60-62, June 28, 1971.
6. "Impurities in Petroleum", Petreco Manual, Petrolite Corp., Long
Beach, CA» 1958.
/ . Control "'ei.l-iniqaes for Sulfur Oxide. In Air Pollutants , AP- 5 2 , U.S.
Environmental Protection Agency, Research Triangle Park, NC.
January 1969.
8. H. N. Olson and K. E. llutchlnson, "How Feasible Are Giant, One--
train Refineries? ", Oil and Gas Joi rnal , 70(1) : 39-43, January 1.
1972.
9. C. M. urban and K. J. Springer, Study of Exhaust Emission.? from
Natural Gas Pipeline Compressor Engines ^ American Gas Association,
Arlington, VA, February 1975.
10. H. E. Dletzmann and K. .T . Springer, Exhaust Emissions from Pistuu
and Gas Turbine Engines Lsea in Natural Gas Transmission, American
Gas Association, Arlington, VA, January 1974.
9.1-24 EMISSION FACTORS 10/80
-------
11. M. G. Klett and J. B, Galeski, Flare Systems Study. EPA-600/2-76-
079, U.S. Environmental Protection Agency, Research Triangle Park,
NC, March 1976.
12. Evaporation Loss in the Petroleum Industry, Causes and Control,
API Bulletin 2513, American Petroleum Institute, Washington, DC,
13. Hydrocarbon Emissions from Refineries. API Publication No. 928,
American Petroleum Institute, Washington, DC, 1973.
14. R. A. Brown, ^t_al., Systems Analysis Requirements for Nitrogen
Oxide Control of Stationary Sources. EPA-650/2-74-091, U.S.
Environmental Protection Agency, Research Triangle Park, NC, 1974.
15. R. P. Hangebrauck, et al. , Sources of Polynuclear Hydrocarbons jn
the Atmosphere, 999-AP-33, Public Health Service, U.S. Department
of Health, Education and Welfare, Washington, DC, 1967.
16. W. S. Crumlish, "Review of Thermal Pollution Problems, Standards,
and Controls at the State Government Level", Presented at the
Cooling Tower Institute Symposium, New Orleans, LA, January 30, 1966.
17. Assessment of Atmospheric Emissions from Petroleum Refining,
EPA-600/2-80-075a through -075d, U.S. Environmental Protection
Agency, Research Triangle Park, NC, 1980.
10/80 i'etrnleuir. Industry 9..1-15
-------
9.2 NATURAL GAS PROCESSING
9.2.1 General'
Natural ga;, from hi^h-pressuri- wells is usually passed through Held separators (< remove hydrocarbon
nondensate and watei at the well. Natural gasoline, butane, and propane are usually pit ?ni in the ^as, and gas
processing plams are required for (he recovery of these liquefiable constituents (see Figure 9.1-1). N-nural gas is
considered "sour" if hydrogen sulCide is present in amounts greater thim 0.25 grain per 100 standard cubic feet.
The hydrogen sulfide (r^S) must he 'srr.oved (called 'sweetening" the ^as) hcrore the £is can be utilized If h^S
is present, the gas is usually sweetened by absorption of the H^S in an ar,,inc solution, / -nine processes are used
for over 95 percent of all gas sweetening in the United States. Proteges such as carbora;; processes, solid bed
absorbents, and physical absorption methods are employed in the other sweetening plant;. Emissions dala for
sweetening processes other than amine types are very meager.
The major emission sources in the natural gas processing industry a;e compressor engirt and acid gas wastes
front gas sweetening plants. Compressor engine emissions are discussed iri section 33.2; therefore, only gas
sweetening plant emissions are discussed here.
9.2.2 Process Description2-3
Many chemical processes are available for sweetening natural gas. However, at present, thf most widely iKerl
method for H2S removal or gas sweetening is the amine typ« process (also known as Ihc Girdlcr process) in which
various amine solutions are utilized for absorbing H2S The process (RNM3)2S (I)
where: R = mono, di, or H-eihanul
N - nitrogen
H * hydrogen
S =• sulfur
The ^covered hydrogen sulfide gas stream may be (1) vented, (2) flared in waste gas flares or modem
omokeless fln;es., (3) incinerated, or (4) utilized for the production of elemental sulfur or other commercial
products. If the rceoveicd l^S gas stream is no' to be utilized as o feedstock for commercial applicsriuns, the gas
is usually passed to a tail gas incinerator in which the H^S is oxidized to sulfur dioxide and then pu^cd to the
atmosphere via a stack For r.iore details, the reader should consult Reference 8.
9.2.3 Pmissicns4-5
Emissions wiii only result from gas sweetening plants if ihe acic >vaste gas from the amine process U flared o:
incinerated. Mcst often, the acid was'e gas h used as a feedstock in nearby sulfur recovery or sulfuri: acid plant:,.
When flaring or incineration is practiced, the maj~> pollutunl of Concern is sulfur dioxide. Most, plants employ
elevated smokelrs^ flares or tail gas incinerators to e.isjre i.omplctt combuslinn of all waste gus constituents,
including virtuu'.ly 100 percent conversion of H2S tc aC^. Little paiiiculatc. smoke, or hydmcarbuns lesult from
these devices, .ind btcause gas temperatures do nol usually exceed !JUCDf- (650°C), significant quantities of
nitrogen oxidi s are not formed. Emission factors for gas sweetening planlr. with smokeless fares or incinerators
are presented in Table 9.2-1.
4/76 Petrolerm Industry 9.2-1
-------
S'!UP GAS FEEDSTOCK TO CHEMICAL PLANTS
O
q
c
ARE (ONLY DURING WELL TESTING
ANDCDMPLFTIONI
t
/JXJ EMERGENCY FLARE OR VENT
N <*- III""
£/• \**\ " *"" SEPARATOhS j j
j ANU 1
' DEHYDRATOHS 1 i
GAS. I 1
OH. A™ I 1 REINFECTION
WAT-« 1 1 IF SWEET
HYDROCARBON WATER
CONDENSATES
REINJECTION FLARE OR
««p..E ,,-*;Sn — ™
cn;in T I * ftPIH PA^ '
GAS C02-H2S
^ ........ §»• SUI FUR RECOV-
UMsncticNiNbrLANi ERY PLANT
SWEET
GAS
SWEET
GAS
i
ELEMENTAL
SULFUR
NATURAL GAS
(Ci + C2)
EMERGENCY Fl ARE OR VENT < ••
T . LIQUIFIED PtTROLEUM
GAS
-------
Tibia 921. EMISSION FACTORS FOR GAS SWEETENING PLANTS"
EMISSION FACTOR RATING: SULFUR OXIDES: A
ALL OTHER FACTORS: C
Process^
Amine
Ib/ia6ft3uas proces,ed
kr.j/103 cr>3 gas processed
Participates
Neb.
Neg.
Sulfur oxides0
IS02)
1685Sd
26.98 Sd
Carbon
monoxide
Neg.
Neg.
Hydrocarbons
Neg.
Neg.
Nitrogen
oxides
Neg.
Neq.
"emiiiion lectors are presented in ihii section only for sr'okeleis 'la.tt and tail gat 'ntinerators on the amine B*i sweeiening
procw. Too little emissions information exists to characterize ermstioni t'om older, law efficient waste gai flares on tha
amine procen or from other, IBM common gat sweetaning processes. Emission factor! for vbrioul internal combustion anyinet
ucliied in a gut procuting plant are given in section 3.3.2. Emission factors lor suHuric acid olanti and uilfur recovery plants
&IB given in section* 5.17 and 5.18, r
ri rApreiant amiuiont after tmokeieu Marai (with fuel gat tnd Meam iRjMtion) or tt-i gai incineratori and ar» '
on RefiranCK 2 and 4 through ~V
cThew factors are batad on tha WRimptlons that virtually 1 00 percent if all HoS in the acid gu waste is converted to SO 2 during
flaring or incineration and that rh« sweetening procots removes essantiBlly 100 percent of tha HjS present in the feeditock.
dS is .ha H^l. contart, c.n a nole percent balii, in the sour gai entering the flfli iweetening plant for ax«np!e, if the H-vS content
is 2 percer.t, the emission factor would b« 1686 limrt 2, or 3370 Ib SO2 per rr illion cubic feet of tour gas prot.eised. If the
H2S mole percent '; unknown, average values from Table 9.2-2 may be substituted.
Note: If H2& i"irtenti are reported in ^raini per 100 set or ppm, use the following factors to convert to mole percent:
0.01 mol% H26 = e.7egrH2S/100«cf et60"F ond 29.92 in Hg
1 fir/100 ecf - 16 ppn. (by volume)
To convert to or from metric units, use the following factor:
0.044 gr/100 ecf - 1 mg/ftm3
ACID GAS
PURIFIED
GAS
*• STEAM
REBDILER
HEAT EXCHANGER
Figure 9,2-2. Flow diagram of the amine process for gas sweetening.
4/76
Pi'troleum Industry
9.2-3
-------
Table 9.2-Z AVERAGE HYDROGEN SULFIDE CONCENTRATIONS
IN NATURAL GAS BY AIR QUALITY CONTROL REGION"
State
Alabama
Arizona
Arkansas
California
Colorado
Florida
Kansas
Louisiana
Michigan
Mississippi
Montana
New Mexico
North Dakota
Oklahoma
AQCR name
Mobile-Pensacola-Panama City -
Southern Mississippi (Pla., Miss.)
Four Corners (Colo., N.M ., Utah)
Monroe-El Dorado (La.)
Shreveport-Texarkana-Tyler
(La., Okla., Texas)
Metropolitan Los Angeles
San Joaquin Valley
South Central Coast
Southeast Dtsert
Four Corners '.Ariz., N.M.. Utah)
Metropolitan Denver
Pawnee
San Isabel
Yampa
Mobile-Pensacola-Panama City •
Southern Mississippi (Ala., Miss.)
Northwest Kansas
Southwest Kansas
Monroe-El Dorado (Ariz.)
Shrevtport-Texarkana-Tyler
(Ariz., Okla. .Texas)
Upper Michigan
Mississippi Delta
Mobile-Pensacola-Panama Ci;y -
Southern Mississippi (Ala., Fla.)
Great Falls
Miles City
Four Corners (Ariz., Colo., Utah)
Pecos-Permian Basin
North Dakota
Northwestern Oklahoma
Fhreveport-Texarkana-Tyler
(Ariz., La., Texas)
Southeastern Oklahoma
AOCR
number
0
14
19
22
24
31
32
33
14
36
37
38
40
5
97
100
19
22
126
134
5
141
143
14
155
172
187
?2
18B
Average
H2S, mol %
3.30
0.71
0.15
0.55
2.09
0.89
3.66
1.0
0.71
0.1
049
0.3
0.31
3.30
0.005
0.02
0.15
0.55
0.5
0.68
3.30
3.93
0.4
0.71
083
1.74b
1.1
0.55
0.3
9.2-4
EMISSION FACTORS
4/76
-------
Table 9.2-2 (continued). AVERAGE HYDROGEN 8'JLFIDE CONCENTRATIONS
IN NATURAL GAS BY AIR QUALITY CONTROL REGION*
State
Texas
Utah
Wyoming
AQCR name
Abilene Wichita Falls
Amarillo Lubbock
Austin-Waco
Corpus Christi-Victoria
Metropolitan Dallas-Fort Worth
Metropolitan San Antonio
Midland-Odessa-San Angelo
Shreveport-Texarkana-Tyler
(Ariz., La. Okla.)
Four Corners (Ariz., Colo., N.M.)
Casper
Wyoming (except Park, Bighorn
and Washakie Counties)
AQCR
number
210
211
212
214
215
217
218
22
14
241
243
Average
H2S, mol %
0.055
026
0.57
0.59
2.S4
1.41
0.63
0.55
0.71
1.262
2.34
8Rttti«nei 9.
bSour gai only r^xirtud for Burkj. William*, and McKenzil Countwt.
cP«rk. Bighorn, and WMhofcit Count)** riport 91* with an tvtrigi 23 met"«- H^S content.
Some plants still use older, leu efficient waste gas flares. Because these flares usually burn at temperatures
lower than necessary for complete combustion, some emissions of hydrocarbons and particulates as well as higher
quantities of H2S can occur. No data are available to estimate the magnitude of these emissions from waste gas
flares.
Emissions from sweetening plants with adjacent commercial plan's, such as sulfuric acid plants or sulfu:
recovery plants, are presented In sections 5.17 and 5.18, respectively. Emission factors for internal combustion
engines us*d in gas processing plants are given in section 3.3.2.
Background material for this section was prepared for EPA by Ecology Audits, Inc."
References for Section 9.2
1. Katz, D.L., D. Cornell, R. Kobayas.ii, F.H. Poettmann, J.A. Vary, J.R. Elerbaas, and C.K Weinaug
Handbook of Natural Gas Engineering. New York, McGraw-Hill Book Company. 1959. 802 p.
2. Maddox, R R. Gas and Liquid Sweetening. 2nd Ed. Campbell Petroleum Series, Norman, Oklahoma. 1974.
298 p.
3. Encyclopedia of Chemical Technology. Vol. 7. Kirk, R.E. and D.F. Othmer (eds.). New York, Interscience
Encyclopedia, Inc. 1951.
4. Sulfur Compound Emissions of the Petroleum Production Industry. M.W. Kellogg Co., Houston, Texas.
Prepared for Environmental Protection Agency, Research Triangle Park, N.C. unJer Contract No. 68-02-1308.
Publication No. FPA-650/2-75-030. December 1974.
5. Unpublished stack test data for gas sweetening plants. Ecology Audits, Inc., Dallas, Texas. 1974.
4/76
Petroleum Industry
9.2-5
-------
6. Control Techniques for Hydrocarbon and Organic Solvent Emissions from Stationary Sources. U.S. DHEW,
PHS, EHS. National Air Pollution Control Administration, Washington, D.C. Publication No. AP-68. March
1970. p. 3-1 and 4-5
7. Control Techniques for Nitrogen Oxides from Stationary Sources. U.S. DHEW, PHS, EHS, National Air
Pollution Control Adir.inistration, Washington. D.C. Publication No. AP-67 March 1970 p. 7-25 to 7-32.
8 Mullins, B.J el al. Atmospheric Emissions Survey of tiie Sour Gas Processing Industry. Ecology Audits, Inc.,
Dallas, Texas. Prepared for Environmental Protection Agency, Resejrch Triangle Park, N.C. under Contract
No. 68-02-1865. Publication No. EPA^50/3-75-076. October I97S.
9. Federal Air Quality Control Repiw»i'i. Environmental Protection Agenjy, Research Triangle Park. N.C.
Publication No. AP-102. January PJ72.
4/76 EMISSION FACTORS 9.2-6
-------
10. WOOD PRODUCTS INDUSTRY
Wood processing involves the conversion of raw wood tn either pulp, pulpboard, 01 one of several types ol
wallbuaid including plywood, pariieleboard, or hardboard. This section presents emissions data for chemical
wood pulping, for pulpboard and plywood manufacturing, and for woodworking operation?. The Burning of wood
waste in boilers and conical burners is not included as it i«. discussed in Chapters I and 2 of this publication.
10.1 CHEMICAL. WOOD PULPING
10.1 I General i
Cliernical wood pulping involves the extraction of i.-elklose from wood by dissolving the lignin that binds the
celluloid fibers together. T ic principal processes used in chemical pulping are the kraft, sulfitc, neutral suifite
semichemical (SSSC), dissolving, and sodj, the first three of these display the greatest potential for causing air
pollution. The kraft process accounts for about 6*> percent of all pulp produced in the Uniied St. tQs;ihe sulfitc
and NSSC processes, together, account for Icsa than 20 percent of the total. The choice .if pulping process is de-
termined by the product being mrde, by the type- of wood specks available, and by eo-nomic considerations.
10.1 2 Kraft Pulping
10.1.2.1 Process Description 1-2—The kiaft process (we Figure 10.1.'2-1) involves the cooking of wood chips
under press-ire in the presence of 3 cocking liquor in either a batch or a continuous digester. The cooking liquor,
or "while liquor," consisting of an jquvous solution of sodium sulfide and sodium hyd -oxide, dissolves the lignin
that binds the cellulose fibers together.
When cooking is completed, the contents of the digester ate forced into the blow tank. Here the mpjor portion
of 'he spent cooking liquor, which contains the dissolved lignin, is drained, and the pr'p en'irs the initial stage of
washing. Prom the Mow tank the pulp passes through the knotter where unrelated chunks of wood are removed.
The pulp is then washed and, in some mills, bleached before being pressed and dried into the finished product.
It is economically necessary to recover both the inorganic cooking chemicals and the heat content of the spem
"black liquoi," which is separated from the cooked pulp. Recovery is accomplished by first concentrating, the
liquor to a level that wi:i supp-jrt combustion and then feeding it to a furnace where burring and chemical recovery
take place.
InuiaJ concentration of the weak blad. hquor. which contains about 15 percent solids, occurs in the multiple-
effect evaporator. Hue process steam is passed countereimeni to the liquoi in a series of evaporatui tubes that
increase the solids content to 40 to 55 percent. Further concentration is then effected in the direct contact
ev;ipoiator. Th:s is generally a scrubbing device (a cyclonic or ventun sciutber or a cascade evaporatoil in which
hot combustion gases from the recovery furnace mix with the incoming black liquor to raise its solids cor'ent to
55 to 70 percent.
The black liquoi concentrate is then sprayed into the recovery furnace where the organic content supports
coi ibu.ition. The in organic compounds fall to the botturn of the furnace and aie discharged to the smell dissolving
tank to form a solution called "green liquoi." The green liquor n then conveyed to a caustici/ei whcie slaked
lime (c.ilcium hydri.xide) is added to convert the solution back to white liqjor. which can be rcuicd in subsequent
cooks. Residual line rluuge from the caustiii/er can be recycled after being dcwatereil and calcined in the hot
lime kiln.
Many mills nee I more steam fo; process heating, for diivmg equipment, for providing electric power, etc., than
can be 'irovided bv the recovery furnace alone. Thus, conventional industrial boilers that burn coal, oil. natural
gas, and in sorrc cases, bark and wood waste are commonly employed.
4/76 Wood Product* Indii.slr) 10.1-1
-------
p
t-'j
CHIPr
rV
z
T;
>
r*
o
H2S. CH3SH, CH3SCH3,
AND HIGHER COMPOUNDS
RELItF
CH3SH, CH3SCH3, H?S
NONCONDENSABLEi
HEAT
EXCHANGER |_
CH3SH, CH]SCH3, Hp
NONCONDENSABLES
TURPENTINE
CONTAMINATED WATER
PULP 13% SOLIDS
SPENT AIR, CH3^CH3,—
AND CHjSSCHs
STEAM, CONTAMINATED WATER.
CONTAMINATED 4 H2S, AND CH]SH
-*• WATER
AIR
I
OXIPAT.CN
TOWEK
CN
K
I
m
<
|
0
re
I
BLACK LIQUOR
50% SOLIDS
DIRECT CONTACT *^
EVAPORATOR 'i-
t
BLACK
CaO
L10UOR 70% SOLIOS^ __^
SULFUR T^ *
RECOVERY
FURNACE
OXIDIZING
ZONE
REDUCTION
ZON
SMELT
f
-AIR
Figure 10 1 2-'i. Typical krafl sulfale pulping anc recovery process
-------
!'~M _.J. Emission and Controls'-^ Paniculate emissions from the kraft process occur primarily from the re-
covery furnace. the lirr.c kiln, and I lie smell dissolving tank These emissions consist mainly of sodium salts but
include SOI.K calcium sails from [he lime kiln. They arc caused primarily by the carryover of solids plus the sub-
limation jnd condcnsjtion of the moiganic chemicals.
Paniculate control i< provijed on recovery furnaces in a variety of ways. In mills where either a cyclonic
scrubbei or cascade evjpur.ilo' serves as the direct contact evaporator, further control is necessary js these devices
are generally only ^0 to.'Oi'ct :ent eff-ciert lor particulates. Most often in these case«,an electrostatic predpi»ator
is cmpioyi-d after the o'iioct contact evaporator to provide an overall paniculate control efficiency of 85 to 5»99
percent In a few mills, however, a venturi scrubber is ulili/ed as the direct contact evaporator and simultaneously
provides 80 to 40 percent partii-ulatc control In cither case auxiliary scrubbers may be included afier the
precipitate! or the vcmuri scrubber 10 provide additional contiol of particulars
Purliculau contio! on link- kilns is generally accomplished by scrubbers Sme',1 dissolving lanks aie o mm only
controlled by mesh pads but employ scrubbers when furthcr control ;.s needed.
The charactehstic odor of the kraft mill is caused in brge part by the emission of hydrogen sulfidt The major
snirte is the direct contact evaporator in which the sodiun: sulfide in the black liquor reacts with the carbon
dioxide in the furnace exhaust. The lime kiln can also be a potential source as a similar reaction occurs involving
residual sodium su tilde in the 1 me mud. Lesser amounts of hydrogen solflde are emitted with the ncncondensible
off-gasses from the digesters and multiple-effect evjporatore.
The kraft- process ouoi also results fiom jn assortment ^f orgor.ic s.»tfur compounds, all of which hive extremely
low odor thresholds. Me;hyl mercaptan and dimethyl sulfide arc forced in reactions with the wood romponent
lignm Dimethyl disulftdc is formed through the oxidation of meica|'tan groups derived from ihc lignin. These
compounds are 'milled from many points within a mill; however, th; main sources are the digester/blew tank
systems and the direct contact evjporator.
Although odoi control devices, per sc, arc not gci.jrjlly employed in kraft mills, control of reduced sulfur
compour ds can be accomplished by process modifications and by optmiizing operating conditions, f 01 example,
black liquor oxidalir. i syslcns. which uxidi/c sulfitJcs into less reactive thiosuifates. can considerably reduce
udorous sulfur emissions from die Jirec' contact evaporate;', althouj;n the vent gases f.orn such systems become
minor cdor sources themselves Noncondcnsi'ule odorous gases vented from the Jigcst-ir.'blow tank system and
multiple-effect evaporators can be destroyed by therm?1 oxidation, usually by passing them thiough the lime
kiln. Optimum operation of the recovery furnace, by avoiding overloading and by maintaining sufficient oxygen
resiciuji and turbulence, significantly reduces emissions of icduced sulfur compounds from this SPUICB. In addi-
tion, u,r use lit" fresh w;itcr in' lead o< contaminated condensales in the scrubbers and pulp washers further reduces
odorous cmi.-ions The c-fli-ct of any of these modifications on a given mill's emissions will vary considerably.
Several new mills have iHcorooratcd iccovcry systems that eliminate ihc conventional direct contact evaporators.
In one ^yslciii, pichealcd c'uiui>us|ion uii ruthci tlian flue gas provides di'cct contact evapcraii:m. In the other.
the multiple-effect cvjporaioi sysieni :< extended to replace ihc direct contact evaporator altogether. lnbothc>i
'.hose ayi-trin!, reduced sultur ctiiiss'ons I'ruiTi the iccuvery funiaee/diicel cuntacl evupoialor n-'portedlv can be
reduced by m ne tl.an '>S pivcont troni convcnticiijl uncontrolled systems.
Sulfur dioxide c-missions icsuh mainly from ixidation of icduccd suifui compounds in the iccovciy furnace,
It is rcfiiirlc'd Ihat ;hc direct contact evjm>ri:lor absorbs 50 to 80 percent -of these emissions', furthei scrubbing, if
employed, ciin reduce lliein jnothcr H) to 20 percent.
Kuicniial sources ol taihoii numoxidc emivsions from the kr;;ft process include the recovery lurnace and li. ie
kiln, TMe major CJI^L- of carhi.n moiioxidi: eiais.sioi.s is furnace operation we!! above rated capacity, making it
nnposMhlc lu maintain oxuh/iiivs
4/77 A otxl Product!* IniluMrv
-------
Some nilrogen oxides are also emitted (rum the recovery furnace and lime kilns although the
amount j arc relatively small. Inductions arc that nitrogen oxides cmi^pions from each of these sources
are on the order of 1 pound per air-dried U-senled
in Chapter 1.
lahie 10.1.2-1 presents emission factors fo> d conventional krafl mi.'I. The mi -t widely used
p.n liculaie controls di vices are shown along with the odor reductions resulting from black liquor
oxidation and >ncim .(inn of nonrondensibl? nff-pas«6.
10.1.3 Arid Sulfito Pulping
10.1.3. 1 Process l)e»criptionu • The production o/ acid sulfite pulp proceeds similarly 20 kratt pulp-
ing except that different chemicals are used in the cooking liquor. In plao* of the caustic solution used
to dissolve the lignin in the wood, sulfurous acid is employed. To buffer the cooking solution, i bisul-
fite of sodium, magnesium, ca'cium, or ammonium is jsed. A simplified flow diugramof a mBgnrsimn-
base process is shown in Figure 10.1.3-1.
Digestion if carried out under high pressure and high temperature in either batch-mode or con-
tinuous digesters in the presence of a sulfurous acid-bisulfite cooking liquor. When cooking it com-
leted, the digester is either discharged •! high pressure into a blow pit or its contents are pumped ,r incinerated. In ammonium-
".,ai-e opt. rations, heat can be recovered from the spent liquor through ''ombustion, but the ammonium
base i» ronttiiined in the process, In sodium- or mugiieeiium-base npcratioi.t. heal, sulfur, and base
recovery are sll f» asilde.
If recovery is ptacticeil, the spent weak red liquor (v!iich contains more than half of the raw
materials ai< disHolved organic poliHi) is concentrated in a multiple-effect evaporator and direct contact
evaporator '.o 55 to 6G percent solids. Strong liquor it sprayer! into a furnace and burned, producing
Hte.tm fnr the digested', evaporatorH, etc., and to meet tie mills power
When mugnefium ba^c liquor is burned, a flue gs> 's produced from which magnesium oxide is
recovered in a multiple c /clone as fine white powder. The magnesium uxide is then water-slaked ana
uoed as circulating liquor ,n a series of venturi scrubbers which are designed to absorb sulfur dioxide
from the flue gas and form a bisulfite solution for use in the cook cycle. W hen sodium-base liquor h
burned, the inorganic compounds are recovered as a molten srmlc containing sodium sulfide and
sodium carbonate. This sms1,' may be processed further and used to absorb sulfur dioxide from the
flue gaaond sulfur burner. In some Hodium-basr mill's howevftr, the omelt may be sold to a nearby kiaft
mill as raw material for producing green liquor.
10.1-4 EMISSION FACTORS 4/'.'
-------
•A
|
9
Zu
c
Table 10.1.2-1. EMISSION FACTORS FORSULFATE PULPING3
lutirt weights at air driad unMnchad pulp)
EMISSION FACTOR RATING: A
Source
Digester relief antl
t '""/«' tank
Brown s>t'>cK ».. hers
Multiple effect
evapnra iC"--
Recovery bnilr- and
df.'ect contact
PV~porator
Type
control
Untreated 'J
PartH'jIates13
!b/ton
^
Untreated •
Untrca'.od^
'Jntreau?dn 150
Ventun
scrubbed
Electrostatic
Aux hary
scrubber
Snnell dissolving Untreated
lank Mesh pad
Lime kiln«s Unlce/ier!
T-jipcritine
condenser
Miscellaneous
sources'
Scrubber
Untreated
Untreated
47
8
3 - '^
5
1
45
3
kg/MT
-
75 .
23.5
4
.5-7 5k
2.5
0.5
22. &
1.5
-
_
Sulfur
oiox ide | SOjl0
Ib/ton
-
0.0?
0.01
5
5
5
3
0.1
0.1
0.3
0.2
-
_
kg/MT
-
0005
0005
2.5
2.5
2.G
1 5
0.05
0.05
0.15
0.1
—
_
Carbon
monoxide'3
Ib/ton
-
—
2 60
2- 60
2 -60
2-60
—
—
10
10
—
_
kg/MT
-
,
_
Hydrogen
Ib/ton
0.1
'-.02
o'l
1
1 - 30
1 -30
1 -30
i -30
—
—
5
5
_
12'
12'
• 2*
12'
004
004
05
05
0.01
_
kg/MT
0.05
0.01
0.05
6'
6'
6'
.. i
u
0.02
002
02&
0.25
0005
_.
R5H. RSR.
RSSR(S"f'f
Ib/ton
1.5
02
0.4
1'
11
1*
n'
kg/MT
075
O.I
0.2
C.51
0.5'
0.51
0.5*
i
0.4
0.4
025
025
0.5
05
0.2
02
0 125
0 125
0.25
0.25
For more detailed data on specn.c Iyp3s nf mills, consult Reference 1.
Relerer.cns 1. 7. 8.
GReler«nces 1. 7, =i tO.
. ices 6. 11. Uso higher value 'or overloaded furnaces
References 1. 4. 7-10. 12. 13. these rediMMd suMur compounds are usually -xp»t.5w»d aa aulfiv.
RSH-methyl meicapcan; RSR dime'!, y I sulfide. RSSH-dimethyl disulfide.
"if th« noncondensible gasos from these sources are ventod to the li-ne kiln recover', furnacu, or equivalent, iric -iniuced sulfur compound?.
are destroynd -
"These Actors apply when either a cycijncr scrubbei or cascade evaporator is used lor direct contact evaporation with rxj furthvr controls.
'Thesfl red'^r-ud ^jllu- compounds (TRS) are typically 'educed by W) percent when black liquv oxidation is employed but can b« cut by 90 lo
99 percent when oxidation is complete ur>-i the re<.overy furnace isoparMed optimally.
'These (actors apply wi«n a veniun sr rubber is used foi direct contact evaporation with no further controls.
Use 15(7 .5) when the auxiliary scrubber follows a venojri scrubber and 3(1-5) when employed after an electrostatic precipitaior.
Includes knoner vents. Crownstock syal tanks, elt
Whc-n black liquor OKidMion is included, a facio: of 0.6(0.3) should be us«d
-------
RECOVERY FURNACE/
•BSORmiMSTREMI
EXHAUST
Sir AH FOR
rpjciss MD rmtm
M
3
o
2!
TJ
>
o
C/2
REOLIOUOR
Figure 10.1.3-1. Simplified process flow diagram of mrjnesium-base process employing
chemical and heat recovery.
-------
If recovery is not practiced, a?i acid plant of sufficient capacity to fulfill the mill's total Bulfite
requirement is necessary. Normally, sulfur is burned in a rotary or spray burner. The gas produced is
then cooled by hen exchangers plua a water spray and then absorbed in a variety of different scrubbers
containing either limeitone or a solution of the base chemical. Where recovery IB practiced, fortifica-
tion is accomplished similarly, although a much smaller amount of sulfur dioxide must be produced
to make up for that lost in the process.
10.1.3.2 Emissions and Controls" - Sulfur dioxide in generally ronsidert-d the major p also potential sources of SOj.
These operations are numerous and may account fora significant fraction of a mill's SO2 emissions if
not controlled.
The only significant participate source in the pulping and recovvi j pi O.TBB is the absorption system
handling the recovery furnace c hauet. Lew particulate is generated in ammonium-base systems than
magnesium- or «odiunvbase systems as the combustion productions ave mostl nitrogen, water vapor,
and sulfur dioxide.
Other major sources of emissions in a sulfite pulp mill include the auxiliary power toilers. Emin-
sion factors for these boilern are presented in Chapter '.
EmiMion factors for the various, sulfite pulping operation!) are shown in Table 10.1.3-1.
10.1.4 Neutral Sulfite Semichcmical (NSSC) Pulping
10.1.4.1 Process Description'-V*-1* - In this process, the wood chips are rooked in a neutral solution of
Hodium aulfite and sodium bicarbonate. The uulfite ion reacts with the lignJn in the wood, and the
sodium bicarbonate acts a« a buffer to maintain a neutral stlution. The major difference between thitt
proceis (as well at all semichemical techniques) and the kraft and acid sulfite processes is that only a
portion of the 1'gniu i» removed during the cook, after which the pulp is furl her reduced by mechani-
La! disintegi aiion. Because of this, yields a* high as 60 to 80 percent can be achieved as opposed lo50 to
55 percent for oth»r chemical proce««r.,.
4/77 Wood Products Industry 10.1-7
-------
T.ible 10.1.3-1. EMISSION FACTORS FOR SULFITE PULPING*
Emission tacti.vb
UiADUF 1 VuAUUWT : it)/
- -( f 'Tms .-tn
Su.fu* pio
/ADUT ] kg'AD'
'AD'JMT
10 •
M.lU
NHJ
'\,H3
\o
v^itini '.i.iij.iiji'
.. c.iu."', vyH.ni
P in ..>s rhj> qi-
\.-u
N...)
f.tg
Neq
1
02
L
25
0.1
2
67
H,
Arrmo-'
m st *• i^T
3i«l.utiitj
0 35
535
13
05
0.2
1
33.5
3.5
A ii iHu.-'l'1 NH j
c;
o,.,, ,>,,,. : A,.
s,.,,, ! NlV N,9
Ji-ns § !w>j Neg
NO-IP • N*^t< Nrg
03
02
8
1?
02 ' C
0.1 ! D
H i C
6 D
BAII emission factors represent long term average emissions.
bFaclors expressed in terms of Ib (kg) ot pollutant per air dried unbleached ton (MTI of pulp. All factors are bxsed on lata
in Reference 14.
-Thtse factors riprasent e -ninions thai occur a'tsr the cook is competed and tvhtn ih* digester contents are discharged in-
to the blow pit or dump tank Some relief jases are vented from the digester during the cook cycle, but th.ise are usually
transferred .j pressure «;cumul?tors, end the SO; therein is reabsorbed for use in the cooki.'n liquor. These factors repre-
sent long-term average emissions: in sor-t mills, the actual emissions will be intermittent and to- short time periods.
^N'-g igible emissioni.
eProcess changes may include such measures as raising the pH of the cootipri, wasners, screens, e*c.
10.1-8
EMISSION F.-MTOHs
1/77
-------
The NSSC process varies from mill to mul. Some mills dispose of Iheir spent liquoi, iome milis recover th:
cooking chemicals, and some, which are operate^ in conjunction w''h kraft mills, mix their spent liquor with thf
ktjft liquor as a source of makeup chemicais. When recovery is practiced, the steps involved parallel those of the
sulfite process.
10.1.4.2 Hmissions and Controls'- '••'• ^articulate emission.; are a potential problem only when recovery
systems are employed. Mills that do practice i icovery, hut ari noi operated in conjunction with kiaf! opeiations
often utilise fluidized bed reactors to burn then spent liquor. Be.'ause the flue gas .-ontajns sodium sulfate and
sodium carbonate dust, I'fident participate collection may ht included to Facilitate chemical recovery,
A potential gaseous pollutant is sulfur dioxide. The absorbing towers, digester/blow tjrik system, and recovery
furnace are the main souoes of this pollutant with the amounts emitted dependent upon the capability of the
scrubbing devices installed for control and recovery.
iuifide can also be emittei1 from NSSC mills using krafl-lype recovery furnaces. The main potential
source is the absorbing tower where a significant quantity of hydrogen sulfide is liberated as the cooking liquor is
made. Other possible sources include the recovery furnace, depending on the operating conditions maintained, as
well as the digester /blow tank system in mills wture some green liquoi is used in the cooking process. Where green
liquor is used, it is also possible that significant quantities of mercaplans will be pioduced. Hydrogen sulfide
emission:) can be eliminated it burned to sulfur dioxide piior to entering the absorbing systems.
Because the NSSC process differs greatly from inill to mill, ai'd because of the scarcity of adequate data, no
emission factors are presented.
Reference*, for Section 10.1
>. Hendrickson, E. R. et al. Conttoi of Aim sphere Emissions in the Wood Pulping Industry. Vol. I. U.S.
Department ot Health, Education and Welfare, PHS, N-itional Ar Pollution Control Administration, Wash-
ington, I) .C. Final report under Contract No. CPA 22-69-18 Mr.rch IC.I97U.
1. Brat, K. W. Handbook of Pulp and Paper Technology. New York, Reinhold Publishing Corporation, 1964.
p. 166-200.
3. Hendrickson, E R. et al Control of Atmospheric hmisiioiii hi 'he Wood Pulping Industry. Vol. 111. U.S.
Department of Health. Lducation, and Welfare. PUS. N»:;onal Air Pollution Control Administration, Wash-
ington. D.C. final report undei Contract No. CPA 2^-69-1^. March 15, 1470.
4. Walthcr, J. E. and H. R. Amber?,. Odor Control in lJie Kraft Pulp Industry. Chtm. Eng. Progress. 6(5:73-
80, March 1970.
5. Galeano, S. P. and K V. Leopold. A Survey of Lmrsions r>t Nitrogen Oxides in the Pulp Mill. TAPPI
M(3):74-76, March 1973.
6. Source test data from the Office ;jf Ai> Quality Phnm..g jnd Standards, U.S. Lnvironmerital Protection
Anency, Ptscarch Triangle Park, N.C. 1172
7 Ajinnsphcric Emissions I'rom the Pulp jnd Pa|tei MjiiLifucturin|> Industry. L1 S Knviromi.cntul rmlec'.ion
Apr-ncy. Research FrungtC Park . N.C Publication N«-. 1TA-450/1-7 V0(>:. S?ptcmbci 1«)7.».
4/77 Wood I'rodiirlf liulusir> 10. !-«>
-------
8. BS isser. R. 0. anil H. B. Cooper. Particulate Matter Reduction Trer-ds in the Kraft Industry. NCASl paper,
Corviillis, Oregon.
9. Paritleld, D. H. Control of Odor from Recovery Units by Direct-Contact Evaporative Scrubbers with
Jxidized Black-Liquor. TAPPI 56.83-86, January 1973.
10. Walther, J. E. and H. R. Amberg. Emission Control at the Kiaft Recovery Furnaces. TAPPI. .55(3):! 185-
1188, August .'972.
11. Control Techniques For Caibon Monoxide Emissions from Statiunaiy Sources. U.S. Department of Health
Education and Welfare, PHS, Nation*! Air Pollution Control Administration, Washington, D.C. Publication
No. AP-65. March 19^0. p. 4-24 and 4-25.
12. Blosser, R. O. el al. An Inventory of Miscelliuieous Sources of Reduced Sulfur Emissions from the Kraft
Pulping Process. (Presents at l:ie 63rd APCA Meeting. Si. Louis. June 14-18, 1970.)
13. FacUirs Affecting Emission of Odorous Reduced Sulfur Compounds from Miscellaneous Kraft Process
Sources NCASI Technical Bulletin No. 60. March 1972.
14. Background Document: AdH Sulfitf Pulping. Prepared by Environmenial Science and Engineering, Inc.,
Gainesville, Fla., for Environmental Protection Agency under Contract No. 68-02-1402, Task Order No, K.
Document No. EPA-4SO/3-V7-005. Resejrch Triangle Park, N.C. January 1977.
IS. Benjamin, M. et al. A General Description of Commercial Wood Pulping and Bleaching Processes. J. Air
Pollution Control Assoc. /9(3):155-161 March 1969.
16. Galeano, S F. and B. M. Dillard. Process Modifications for Air Pollution Control in Neutral Sulfite Semi-
Chemical Mills. J. Air Pollution Control Assoc. 22i'3): 195-199, March 1972.
10.1-10 EMISSION FACTORS V77
-------
10.2 Pl'LPBOARI*
10.21
Pi Ipho. .ul miimihiciiiimii is wo vcs .'he l.ihiicjlion ol tihiou> him ids i'loin j puli; \luny I lu^ includes iwi> ibv
lir.cl types ol piod i; j|. pjpcrbiihi.'>, i shed !l '. i 2 null
(0.3G nun) in moie in thickness i.uidc o! libious imiieiiul on j |,.ipi%i- 1; Mining im clime . - I ihjrhoiird. also iclcttcu
In as pjilitlc hoard, is thicket llun ,>apvihoji:I| uii'U'i llic
screen ', i.i'ner 50 to M) ;x%rtcni ol ihc moisi 10 (.union! is icniimcd in ilic- dryum sivjintu. The Jncd h;>jid
then eni^'is (lie calendar slack, which imparts the hniil ^Jifucc >u ihc pr.)ducl.
In the marrjiJCIurc of fihcihourd. I lie slimy Ihal rcir.ams jfler pulping is washed and scnl lo ihc slock clif-ls
where si/ing ii added. The rcl'ineJ fihci Ironi ihc slock chcsls is led ID llic hc'iid box ol ihc hoind iiKulnnc. The
stock is next led on:<> the fonning .sciecns a;.i\ scni lo d rye is. allcr wliuh the diy product is I'liully of product : Ib/ton \_ kg/MT
Pdperboaid Ntg Neo
Fiberhoardh 06 03
aC mission I act o is i;xpiei«er1 as urn is oei umi weight ul dmihert
tflelc.cncc 1.
References for Section 10.2
I. An FollutaiU Kinission Kactois. Resources Keseuich. Inc.. Kesion Viigmu l'ivp;;icd ii>i \jn>:'i.i) Ar
Poiuitinri ("onliiil Adiiiinislijlion. Wjslniigioii. D.C. mulct Contrail No l'PA-22-i'' ' i '>. -\psil lv)70
2. The Diclioiuiiy ol P;ipci. New Yoik. Aincncan Pjjx'i and Pulp ASMICIUIIOU. ll'4l).
:(76 Wood Prorfiit-lH ln«l«Blr\ 10.2-1
-------
.V Hou^h (i. W. .null J (im-v>. Aii I minion ( oni'ol MI .1 Vlmii -in I'nlp .inil I'.ijvi Mill An.i-i. I'.IJK > l.ulii >l iv
M Mi, l-Vhrimy I'^'l
-I I'liiliiiidii Coninil Hnijsu-sv J \n 1'olliiiiini Citniitil A\MK / 7 410. June IM<)7
S Pnvjlf ^iiiiiiiiunicjl.'ii] holwoci) 1. ticlhi .in ,md IIIL \:iln
-------
10.3 PLYWOOD VENEER AND LAYOUT OPERATIONS
10.3 1 General1"3
Plywood is a Duilding material consisting of veneers (thin wood
layers or plies) bonded with dn adhesive. The outer layers (laces)
surround a core which Is usually 1-imber, veneer or particle board.
Plywood uses are many, Including wall siding, sheathing, roof decking,
concrete formboards, floors, and containers. Moat plywood is made from
Douglas Fir or other softwoods, and the majority of plants are in the
Pacific Northwest. Hardwood veneers make up only a very small portion
of tctal production.
In the manufacture of plywood, log., are sawed to the desired
.length, debarked and peeled into veneers of uniform thickness. Veneer
thicknesses of less than one half inch or one centimeter are conunon.
These veneers are then transported co veneer dryers with one or more
ducks, to reduce th?ir moisture content. Dryer temperatures are held
between about 300 and 40C°F (150 - 200°C). Aft*r drying, the plies go
through the veneer layout operation, where the veneerc are sorted,
patched and assembled in perpendicular layers, and a thermosetting resin
adhesive applied. The veneer assembly is then transferred to a hot
press where, under pressure and steam heat, the product is formed.
Subsequently, all that remains is trimming, face sanding, and possibly
some finishing treatment to enhance the usefulness cf the product.
Plywood veneer and layout operations are shown in Figure 10.3-1.
2-8
JO.3.2 Emissions and Controls
Emissions from the manufacture of plywood include particular
matter and organic compounds. The main source of emissions is che
veneer dryer, w*.th other sources producing negligible amouncs of organic
compound emissions or fugitive emissions. The log steaming and veneer
drying operations produce combustion products, and these emissions
depend entirely on the type of f'l^l and equipment uced.
Uncontrolled fugitive particulate matter, in the form of sawdust
and other small wooa particles, comes primarily from the plywood cutting
and sanding operations. To be considered addition"! sources of fugitive
parLiculate emissions are log debarking, 1'g sawing and .sawdust handling.
The dust ;:hat escapes into the air fr.fi sanding, sawing rnd other wood-
working oper-.tions may be controlled by collection in an exh-iust system
and transport through duct work to a sized cyclone. Section 10.4
discusses emissions from such woodworking waste collection operations.
Tstimates of urrnntrolled particulate emission factors for leg debarking
and sawing, sawdust; pile nandling, and plywood sanding and cutting are
given in Table 10.3-1. From the veneer dryer, and at stack temperature?.,
the onJy particulate emissions are small amounts of wood fibev particles
in concentrations of less than 0.002 Krams per dry standard cubic foot.
uu.l Troilm I- linlli-lr\ I.)..'{-!
-------
fugitive
participate
LOG
STORAGE
LOG
DEBARKING
AND
SAWING
LOG
STEAMING
fugitive
particulate
organic
compounds
I
VENEER
1
VENEER
VENEER
LAYOUT
AND
JLUE SPREADING
organic
compoundB
fugitive
particulate
PLYWOOD
CUTTING
fugitive
particular
PLYWOOD
SANDING
Figure 10.3-1, Ply/ood veneer and layout operations
4,5
10.3-2
EMISSION FACjORS
2/HO
-------
Table lU.3-1. UNCONTROLLED FUGITIVE PARTICULATE MISSION
FACTORS FOR PLYWOOD VENEER AND LAYOUT OPERATONS
EMISSION FACTOR RATING: E
Source
Particu.l ates
Log debarking
Log saving
t
Sawdust handling
c
V»neer lathing
Plywood cutting and
sanding
0.024 Ib/tor.
0.350 Ib/ton
1.0 Ib/ton
NA
0.1 lb/ft2
0.012 kg/MT
0.175 kg/MT
0.5 kg/MT
NA
0.05 kg/m2
Reference 7. Emission factors are expressed as units per unit weight
of logs processed.
Reference 7. Emission factors are expressed as units per unit weight
of sawdust handled, including sawdust pile loading, unloading and
storage.
Estimates not available.
Reference 5. Emission factors are expressed as units per surface area
of plywood produced. These factors are expressed as representative
values for estimated values ranging from 0.066 to 0.132 lb/ft2
(0.322 to 0.644 kg/in2).
The major pollutants emitted from veneer dryers are organic compounds.
The quantity and type of organics emitted vary, defending on the wood
species and on the dryer type and i.s method of operation. There are
two discernable fractions which are released, condsnsibles and volatiles.
The condensible organic compounds consist large].y of wood resins, resin
acids and wood sugars, which cool outside the stack to temperatures
btlow 70°F (21°C) and combine with water vapor to form a blue haze, a
water plume or bothi This blue haze may be eliminated by condensing the
organic vapors in a finned tuV>e matrix heat exhanger condenser. The
other fraction, volatile organic compounds, is comprised of terpenr^ and
natural ga'j components (such ar. unbi rned methane), the latter occurring
only when gas fired dryers are used. The amounts of organic compounds
released because of adhesive use during the plywood pressing operation
are negligible. Uncontrolled organic process emission factors nre given
in Table 10.3-2.
\\
-------
Table 10.3-2. UNCONTROLLED ORGANIC COMPOUND PROCESS EMISSION
FACTORS FOR PLYWOOD VENEER DRYERS8
EMISSION FACTOR RATING: B
Volatile
Organic Compounds
Condensible
Organic Compounds
Species
Douglas Fir
sapwood
steam fired
gas fired
haartwood
Larch
Southert pine
Other5
lb/104 ft2
0.45
7.53
1.30
0.19
2.94
0.03-3.00
Kg/104 m2
2.3
38.6
6.7
1.0
15.1
0.15-15.4
lb/104 ft2
4.64
2.37
3.18
4.14
3.70
0.5-8.00
kg/104 m
23.8
12.1
16.3
21.2
18.9
2.56-41.
2
0
a
Emission factors are expressed in pounds of pollutant
per 10,000 .luare feet of 3/8 inch thick veneer dried, and kilograms
of pollutant ter 10,000 square meters of 1 centimeter thick veneer
dried. All dryers are steam fired unless otherwise specified.
These ranges of factors represent results from one source test for
each of the following species (in order from least to greatest
emissions): Western Fir, Hemlock, Spruca, Westevn Pin'* and
Ponderosa Pine.
References for Section 10.3
1. C.B. Hemming, "Plywood", Kirk-Othmer Encyclopedia of Chemical
Tec hnology, Second Edition, Voluwe 15, John Wiley & Souc, Inc., New
York, NY, 1968, pp. 896-907.
2. F. L. Monroe, et_ al_. , Investigation cf Emissions irom Plywood
Veneer Oryers, Washington State University, Pullman, WA, February
1972.
3. Theodore Bauroeister, ed., "Plyvood", Standard Handbook for
Mechanical^ Engineers, Seventh Edition, McGraw-Hill, New York, NY,
1967, pp. 6-162 - 6-169.
4. Allen Mick and Dean McCarg-'ir, Air Pollution Pioblem_8_ in Plywood,
ParticiPbnard, and HarJboar.1 Mills "in the Mid- Willamette Valley,
Mid-Willamette Valley Air Pollution Authority, Salem OR,
March 24, 1969.
10..VI
EMISSION FACTORS
2/«0
-------
5. Controlled and Uncontrolled Emission Rates and Applicable
limitations for Eighty Processes, Second Printing.
EPA-340/1-78-004, U.S. Environmental Protection Agency, Research
Triangle Park, NC, April 1978, np. x-1 - X-6.
6. John A. Danielson, ed.. Air Pollution Engineering Manual,
AP-40, Second Edition, U.S. Environmental Protection Agency,
Research Triangle ParV., NC, May 1973, pp. 372-374.
7. Assessment of Fugitive Participate Emission^Factors for
Industri_al Processes. EPA-450/3-78-107, U.S. Environmental
Protection Agency, Research Triangle Park, UC, September 1978.
8. C. Ted Van Decar, "Plywood Veneer Dryer Control Device",
Journal nf the Air Pollution Control Association, 22^:968,
December 1972.
2/KO Wornl l'n>.l,i.M- In.lu-lrx
-------
10.4 WOODWORKING WASTE COLLECTION OPERATIONS
10.4.1 General1 *
Wixxiworking, as defined in this section, includes any operation th.it invo)'?i (he generation of small wood
waste panicles (shavirgs, sam'erdust, sawdust, etc.) by any kind of mechanicaj manipulate n of wood, bark, or
wood byproducts. Connnuii woodwot* ing operations include nwing. planing chipping, shaping, moulding.
hogging, lathing, ii",d sanding. Woodworking operations are found ii! numerous industries, such as sawmills,
plywood, particlehmrd, and hardboard plants, and furniture manufacturing plants.
Most plan!-' engaged in woodworking employ pnet'Tiatic transfer systems to rtrnuve the generated wood waste
from ihe immediate proximity of each woodworking operation. These systems are necessary as a housekeeping
measure to eliminate the vast quantity cf waste material ihdl would otherwise accumulate They are also a
convenient means of transporting the was;e mateii*! to common co-It :tion pjints for ultimate disposal. Large
diameter rycKmes have historically hejn tne primary means of separating thr waste malenl from Ihe airstreams
in ihe pi.eumatu transfer systems, although baghouses have recently he--n installed jn sorn? plants for this
purpose.
The waste ir.aterial collected in the cyclones or bagho^^es may be burned in wood waste boilers, utilized in (he
manufacture of ulhei products (such as pulp or particlehoard), or incinerated in conical (teepee/wigwam)
bu tiers. The (alter practice is declining with the advent of more stringent air pollution control regulations and
because of the economic attractiveness of utilizing wood waste us a resou'ce.
10.4.2 Emissions1'
The only pollutant of concern in wuodwmking waste collection opvulinrs is partiiulate matter. The major
emission points are the cyclones utilized in 'he pneumatic transfer systems The quantity of particular emis-
sions from a g'ven cyclone will depend on Ihe dimensions of the cyclone, the velocity of thr LUFstuam, and the
naturt of the operation generating the waste. Typical large diameter cyclones found in the industry will or.ly
effectively collect particles greate. than 40 micrometers in diameter. Baghoujes, when employed, collect essen-
tially all ((" the waste material in the airstream. The wastes from numerous pieces of equipment often feed into
the same cyclone, and it is common for the material volleoted in one or several cyclones tn he cnnvcyeJ to
another cyclone. It b also possible for portions of the waste generated by a single operation to bt directed to
different cyclones.
Because of this complexity, it is useful w'len evaluating emissions from u given facility lo consider the waste
handling cyclones as air pollution sources iustejd of the vaiiojs woodworking operations that actually generate
the parliculate mallet Emission factors foi typical large diameur cyclones irilucU for waste culiection in
woodworking operations are given in Table 10.4 1.
Emission factors R>i wood waste boileis, conical burners, and various drying I'ppralions-oi'ten iouiiJ in
facilities employing woudwo-king operations ire ^ivr-n in Sections 1.6. 2.3, 10.2, and 10.3.
2/BO \\ I Product- hHliMn 10.4-1
-------
Table 10.4.1. PARTICULATE EMISSION FACTORS FOR LARGE DIAMETER
CYCLONES IN WOODWORKING WASTE COLLECTION SYSTEMS*
EMISSION FACTOR RATING: D
Typ« of waste handled
Sanderc)ustd
Other6
r'articulate emissions1-1'"
gr/scf
0.055
(0.005-0.16)
0.03
10.001-0.16)
g/Nm3
0.126
(0.01140.37)
0.07
(C.002-0.37)
lb>hr
5
(0.230.0)
2
(0.03-24.0)
kg'hr
2.3
(0.09-13.6)
0.91
(0.014-10.9)
'Typic*.' waste collection cv_ion»i range from 4 tc 16 fee. (1.2 to d.9 meters) n dun ste-
and employ airflow* ranging from 2,000 (o 26,000 standard cubic feel 157 lo 740 normal
cubir meter%) prr Tiinute. Note' if boghous?* are jsi'd for waste collection, particulBte
•minions mill be negligible.
bR«tl»rencei 1 through 3.
cOb»ri/ed value ranges are >n parentheses
''Thete factors ihouid b« used whenever waste from sanding aperariom is fed directly into
the cyclone in question.
*Theje factors should be used for cyclones handling west-' from all operations other than
tonding. Thu includes cyclones that handle wane (including £Jnd<>rdust) already cnllected
by mother cyclo,ie.
References for Section 10.4
1. Source test data surplied by Robi rt Hams. Oregon Department of Environmental Quality, Portland, OR,
September 1975.
2. J.W. Walton, et at., "Air Pollution in the Woodworking Industry". Presented a* ihe 68th Annual Meeting of
the Air Pollution Control Association, Boston, MA, June 1975.
3. J.iX Hatton am.' J.W. Walton, "Applying the High Volume Stack Sampler To Measure Emissions from Cotton
Gins, WoodwoiKinf! Operations, and Feed and Grain Mills", Presented at 3rd Annual . Informalion supplied by the North Carolina Department of Naural and Economic Resources, Raleigh, NC,
December 1975.
III. 1-2
EMISSION FACTORS
2/HO
-------
10.4.3 Fugitive Emission Factors
^ince mo.«t woodworking operations control emissions out of necessity, fugitive emissions are seldom a
prublf m. Howpvpr. the wood waste storage bins are a common source oi'fu(:ili\c emissions. Table. 10.-1-2
show* these emission .-.ources and their corresponding t>liiis.oion lactur*.
Inlurniatbn conrevninj: si^>" cluMat'teristii's is very limited. D.tta collected in a wei-tern red cedar lurni-
iartury eijuipped v»ith evhanst ventilation on most w»odwoi king ei|iiipini'iit slmweci innsl siif
•> in 'he vtoikinp cmironincnt lo be less than 2 ^m in diameter.7
Table 10.4-2. POTENTIAL UNCONTROLLED
FUGITIVE PARTICULATE EMISSION FACTORS
FOR WOODWORKING OPERATIONS
EMISSION FACTOR RATING C
Type of operation
Wood waste storage bin ventb
Wood waste storage bin loadout0
Pirliculates3
Ib/toi
1.0
20
kg;MT
0.5
1.0
'Factors expitssed as units per unit weight >1 *ood waste handled
^engineering judgment based en plant visits
Additional Reference for Section 10.4
7. Lester V. Crallfy.et al.. Industrial Enivronmental Health, th? Woikvr and the ^ommuniiy. Academic
Press, New Yurk ttnd f.inulon, 19V2.
7/79
Wood Processing
10.4-3
-------
MISCELLANEOUS SOURCES
This chapter contains emission factor information on those source categories that differ substantially from—and
hencv: cannot be grouped with-the other "stationary" sources discussed in this publication. These "miscellaneous"
emitters (both natural a'ld man-made) are almost exclusively "area Sources", that is, their pollutant generating
processes) are dispersed over Urge land areas (for example, hundreds of acres, as in the case of forest wildfires), a*
opposed to sources emiuing from one or more stacks with a total emitting area of only several square feet. Another
chaiicteristic these sources have in common i- the nonspplicabilit>, in most Cases, of conventional control
methods, such us wet/dry equipment, fuel switching, process changes, itc. Instead, control of these emissions,
where possible at all, may include such techniques ?.<- modification of agricultural burning practices, paving with
asphalt or concrete, or stabilization of din roads. Finally, miscellaneous sources generally emit pollutants
intermittently, when compared with most stationary point sources. For example, a forest fire may emit large
qjpntitiej of paniculate? and carbon monoxide for several hours or even days, but when measured against the
emissions nf a continuous emitter (such as a sulfuric acid plant) over a lung period of time 0 year, for example), its
emissions may seem relatively minor. Effeus on air quality may also to of relatively short-term duratior.
11.1 FOREST WILDFIRES
11.1.1 General1
A forest "wildfire" is a large-scale natural combustion process that consumes various ages, sizes, and types of
bot.uucal specimens growing outdoors in a defined geographical area. Consequently, wildfires are potential sources
of large amounts of air pollutants th.ii should be considered when trying to relate emissions to air quality.
The size and intensity (or even the occurrence) of a wildfire is directly dependent on such variables as the local
meteorological conditions, the species of trees and their moisture content, and the weight of consumable fuel per
acre (fuel loading). Once a fir: begins, the dry combustible .naierial (usually small undergrowth and forest floor
litter) is consumed first, and if the energy release is large and of sufficient deration, the dry fug of green, live
material occurs with subsequent burning of this material as well as the larger dry material. Under proper
environmental and fuel conditions, this process may im'iiite a chain reaction thai results in r widespread
conflagration.
The complete combustion ot a forest fuel will require a heat flux (temperature gradient), an adequate c-xygen
supply, and sufficient burning time. The iize and nuantity of forest fue'a, the meteorological conditions, and the
topographu features interact to modify and change the burning behavior as the fire spseads; thus, the wildfire will
attain different degrees of combustion duiing its lifetime.
T:ie importance of both fuel type and fael loading or. tht fire process cannot be overemphasized. To meet the
pressing n«eJ fcr this kind of information, tJ;e L'.S. Forest Service is developing a country-wide fuel identification
sy'iem (moid) that will proviue estimates of fuel loading by tree-size class, in tons per acr:. Further, che
environmental parameters of wind, slope, and expected moisture changes have been superimposed on this fuel
model a:id incorporated into a National Fire Danger Rating System (NF-DR). This system considers five classes of
fuel (thiee dead and t\vo living), the components of which are selected on the basis of combustibility, response to
rnoiiture (for the dead fuels), and wheth. < the living fuels are herbaceous (plants) or ligneous (trees).
Iv'osi fuel loading figures arc based on values for "available fiiel" (corrbustible material that will be consumed in
a wildfire under specific weather conditions). Available fuel values must not be confused with corresponding values
|.»r either "total fuel" (all the combustible material that would burn under the most severs weather and burning
II.1-1
-------
conditions) Of "pjlential fuel" (the larger woody material that remains even jftei an extremely high intensity
wildfiie). It must be emphasi/cd, ho.vever, 'hat the various methods of fuel identification arc of value only when
they are relaled to the existing fuel quantity, the quantily consumed by the lire, ana the geographic aru and
conditions undei which the fire occurs.
Kor the sa1 e of c informity (and convenier;i-e), esiimaled fuel loadings wore ubta;,ied for the vegetation in the
National Forest Re^ons and the wildlife • reas established by Hie U.S. Foiest Se-vice, and are piesented m Table-
11.1-1. Kigiire 11.) -I illustrates tne.,e areas and regions.
Table 11.1-1. SUMMARY OF ESTIMATED FUFl
CONSUMED BY FOREST FIRES8
Area and
Region •'
Rocky Mountain group
Region 1 :
Rigion 2:
Rtijion 3:
Region 4:
Nor;bern
Hocky Mountain
Southwestern
Intermountain
Pacific group
Region 5:
Region 6:
Region 10:
California
Pacific Northwest
Alaska
Coastal
Interior
Southern group
Region 8:
Southern
Eastern group
North Central group
Region 9:
Conifer;
HardvwocG.'.
Estimated average fuel load ng
MT/heci.are I '.on/acre
83 i 37
135 1 60
67 | 30
22 1 10
40 | 8
43
40
135
36
135
25
2C
20
25
25
22
27
19
18
60
16
60
11
9
9
11
11
10
12
HeiL'-cnce 1.
See Fiyuru 11.1-1 lor regional boundaries.
11.1.2 Emissions and Consolsl
It has been hypothesized (but not proven) that '.te mture and amounts of air pollutant emissions arc directly
related to tile intensity and direction (.clatr e u> the wind', ol the wildfire. ;ind indirectly related to the rate .11
which the fir1: spreads. The factors t!;;i ali'ec' \\\>* riitc o! spread are (1) weather (wind velocity, an.uk--'
temperature, anii relative humid''-', (2) luels (luci 'ype. I'icl bed arra\. moisture content, and fuel si.-.c), and (3)
topog'aphy (^li)pe and profile). Hovvcver, logistic,!! pio'jT- (such as si/e of the burning area) and difficulties in
safely situating personnel und EC 'iprient t:jse to ih.. fire have prevented the collection of any rcl'aDlo
experimental emission data on dc;ual wild'lres si> (hit it 's p'es»ntly impossiblL- to verify or dispro"» ihc
above-slated hypothesis Therefore, until such ir.f;rvr: nient>> aift made the only available information is thai
II. I-':
FACTORS
1/75
-------
• HEADQUARTERS
REGIONAL BOUNDARIES
Figure 11.1-1. Forest areai and U.S. Forest Service Regions.
obtained hum burning c?:pcnrncnls in tne laboratory. These data, in the forms of both emissions .. omission
factors, are contained in lable II (-2. Il 'Dust be emphasized thai !he fjciois presented htre ye adequate for
laboiatory-scale emissions estiniaies, but t'.ial subslanlia! er >rs inuy result if they .^e -ised to calculate actui'l
wilufire emissions.
The emissions and emission factors disphyeJ ii, Tj'>le I I .i -2 are calculated using th"! I'ollitwing. l
where: Fj = FJ.mission factor (mass of pollutant/unit area of forest consumed)
PJ = Yield for pollutant l'i" (muss of pullutjrI/urn1, ma^s of forest fuel
= 8.S kg/MT (17 Ih.'ion) for tola! participle
- 70 kg/MT (T 40 Ib'lun) for carbon monoxide
= 12!cg/MTi24 Ib/loii) lor total hyurotarhon (asCII4)
I/7S Internal Comhustion Engine Sources
11.1-3
-------
Table 11.1-2. SUMMARY OF EMISSIONS AND EMISSION FACTORS FOR FOREST WILDFIRES8
EMISSION FACTOR RATING: D
Getxyaph.c area'3
Rocky Mountain
group
Northern,
Ret) i en 1
Rocky Mountain.
Region 2
Soutnwestei.i,
Picjjion 3
Intermix: ntain.
Region 4
Pacific group
California.
Region 5
Alaska,
Region 10
Pacific N.W.
Region 6
Southern yrcup
Sctithern,
Region 8
North i>nt;ai ^roup
Eastern. Region 5
(Both groups ere
in Region 9)
Eastern group
(With Region 5)
Total United States
Area
const.! med
by
wildfire.
ractares
313,397
142,276
65.882
83,765
'\Jr
-------
= 2 kg/MT (4 Ib/ton) for nitrogen oxid.-s (NOX)
= Negligible for sulfur oxides (SOX)
L = rue I loading consumed (mass of forest fuel/unit land area burned)
A ~ Land area burned
E, = Total emissions of pollutant "i" (mass of pollutant)
For example, suppose that it is .a-cessary to estimate the loial paniculate emissions (rum J 10,000 hectare
wildfire in the Southern area (Region! 8). From Tible 11.1-1 it is seen tint 0 e average fuel loaii'n?, is ?U
MT/heclarc (9 ton/acre). Further, the pnll'j.ant yiolj for p.rticulat:s is 8.S kg/MT (17 Ib/ton). Th;ri:fore, lilt-
emissions are:
E = (8.5 kg/Ml of fuel) (20 MT of fuel/hectare) (10,000 hectaics)
H = 1,700,000 r-.g = 1.700 MT
The mosl effective method for controlling wildfire emissions is, of course, 10 prevent Ihe iKCurrencc ol forest
Tires using various means at the forester's disposal. A frequently used technique for reducing .vildfirc occurrence is
"prescribed" or "h^^ird reduction" burning. This type of managed turn involves conibuslioii of litter and
unde'brush in order to prevent fuel buildup on the forest floor and thus reduce the dange. of a wildfire Although
some air pollution is ee nerd ted by this preventativr burning, the net amount is believed to be a u-ljtively smaller
quantity than thai produced under a wildfire situation.
Reference for Section 11.1
1. Development of Emission Factors for 'estimating Atmospheric Cnii.
-------
11.2 FUGITIVE DUST SOURCES
Significant atmospheric dust arises from the mechanical disturbance of
granular materi.il exposed to the iir. Dust generated from these open
sources is termed "fugitive" because it is not discharged to the aLmcsplu're
in a confined flow stream. Common sources of fugitive Just include unpaved
roads, agricultural filling operations, aggregate storage piles, and heavy
construction operations.
For the above categories of fugitive dust sources, the dust generation
process is caused by two basic physical phenomena:
1. Pulveiization and abrasion of surface materials by application of
mechanical force through implements (wheels, blades, etc.).
2. Entrainment of dust particles by the action of turbulent air cur-
rents, such as wind erosion of an exposed surface by wind speeds over 19
kilometers per hour (12 miles/hr).
The air pollution impact of a fugitive dust source depends on the
quantity and drift potential of the dust particles injected into the atmo-
sphere. In addition to large oust particles that settle out near the
source (often creating a local nuisance probiemj , considerable amounts of
tine particles are also emitted and dispersed over much greater ' likely to undergo impeded settling. These
pdrticles, depending upon the extent of atmospheric turbulent.-, ar; likely
to settle within a few hu.idred feet from the ro.id. Smaller particles, par-
ticularly those less th.'in 10 to 15 micrometer? in diameter, have mucn
slower f ravi tat ional settling velocities :in-) are much move likely to have
their t..ttling rate retarded by atmospheric turbulence. Thus, based on tli-
pii-senily available data, it appears appropiiatc to report only those par
tides smaller than 3C iir.crometers Future updates to this document are
expected to defr'ne appropriate factors for other particle sizes.
Several of the emission factors presented in this Section are ex-
uressed in terms of total suspended particulate (TSP). TSP denotes wha-
is measured by a ?tar.dard high volume sampler. Ke«.pnt wind tunnel studies
have shown that the particle mass captur.- ci f i i .IMH y curve foi the tup'1
volume sampler ir very bro~-J, extending from 100 percent capture of parti-
cles smaller than 10 micrometers to a ft-w percent capture of particles is
large as 1CJO micrometers. Alj\), the capture efficiency curve varies with
5/83 Miscellaneous Sources 11.2-1
-------
wind speed and wind direction, relative to root ridge orientation. Thus,
hi^h \.jlnme samplers do not provide de initiv^ particle si/e xiiformiticm
for emission factors. However, ;m effective rutpoint of 30 micrometers
aerodynamic di.iroetr-r is frequently assjg-ied to the standard high volume
sampler.
Control Lechni(|ues for fugitive di st sources g^iU" ,i 1 Iv involve water-
ing, chemical stabilization, or reduction of surface wind speed with wind-
breaks or source enclosures. Wate.-n nr,, i he most comi-.un ;>.nd generally least
expensive method, provides only temporary dust control. The us-,- ot chemi-
cal; to creat exposed surfaces provides longer dur.t si'pprossion but may he
cos'.ly, havr advers^ effects on }>lant and animal lite, e
treated material. Windbreaks -irul sourrf enclosure's are often impractii-a 1
UL'e of the sizt; of fugitive dust sources.
11.2-2 EMISSION FACTOKj
-------
11.2.1 UNPAVED R1ADS
11.2.1.1 General
Dust plumes trailing behind vehicles traveling on unpaved roads are a
familiar sight in rural areas of the United States. When a vehicle travels an
ur.paved road, th: force of the wheels on the road surface causes pulverization
of surface material. Particles are lifted and dropped from the rolling wheels,
and the read su-face is exposed to strong air currents in turbulent shear with
the su face. The turbulent wake behind the vehicle continues tv act on the
road surface after the vehicle has paa.ied.
11.2.1.2 Emissions And Correction Parameters
The quantity of dust ecussions froot a given segment of unpaved road varies
linearly with the volume of traffic. Also, field investigations have shown
that missions depend on correction parameters (average vehicle speed, average
vehlrle weight, average number of nhtslB per vehicle, road surface texture and
roac surface moisture) rhat characterize the condition of a particular road and
the associated vehicle traffic.^"^
Dust emissions from unpaved roads have been found to vary in direct
proportion to the fraction of silt (particles smaller than 75 micrometers in
diameter) in the road surface materials-* Tht allt fraction is determined by
measuring the proportion of loose, dry surface Just that passes a 200 mesh
screen, using the ASTM-C-136 method. Table 11.2.1-1 summarizes measured silt
valuer, for industrial anu rural unpaved roads.
The silt contend of a rural dirt road will vary with locution, jnu it
should be measured. As a conservative approximation, the ollt content oi the
parent soil in the area can be used. However, tests show that road silt con-
tent is normally lower than In the surrounding parent soil, because the fines
are continually removed by the vehicle traffic, leaving a higher percentage
ot coarse particles.
Unpaved roads have a hard nonporous surface that usually dries quickly
after a rainfall. The temporary reduction in emissions because of precipita-
tion may be accounted for by not considering emissions on "wet" days (more than
0.254 millimeters [0.01 Inches] of precipitation).
The following empirical expression may be used to estimate tht quantity of
size specific p^rticulata emissions from an unpaved road, per vehicle kilometer
traveled (VKT) or vehicle raile traveliM (VMT), wlr'i -i .-.V
or PS
S/05 Miscellaneous Sources 11.2.1-1
-------
TABLE 11.2-1-1. TYPICAL SILT CONTENT VALUES OF SURFACE MATERIALS
ON INDUSTRIAL AND RURAL 11NPAVED ROADS3
ro
r- «
V-
r-t
0
z
0
0
(A
Industry
Copper smelting
Irun and steel production
Sand and gravel processing
Stone quarrying and processing
Taconite lining and processing
Wes'e^n surfac.e coal mining
Rural roadc
Road Use Or
Surface Material
Plant road
Plant road
Plant read
Plart road
Haul road
Service road
Access road
Haul road
Scraper road
Haul read
(freshly
graded)
Gravel
i
1
o
Dirt
Crushed limestone
Plant
Sites
1
9
1
1
1
1
2
3
3
2
!
7
2
Test
Samples
3
20
3
5
12
8
2
21
10
5
1
5
8
Silt (*. w/w)
Range
[15.9 - 19.1J
4.0 - 16.0
[4.1 - 6.0]
[19.5 - 15.6]
[ 3.7 - 9./]
[ 2.4 - 7.1]
4.9 - b.3
2.8 - 18
7.2 - 25
18 - 29
NA
i.8 - 68
7.7 - 13
Mean
[17. 0|
8.0
[4.8|
[14.1]
[5-8]
[4.3]
5 .1
8.4
17
24
[5.0]
28.5
9.6
aReferenceB 4 - LI. Brackets indicate silt values based on samples from only one plant- site.
OP NA = Not available.
-------
wheru: H = omission factor
k = par'jic.U: siz^ multiplier (dimension ..ess J
s = silt content of load surface material (/i)
S = meju vehicle c-peeu, kr.i/hr (mph)
W = niean vehicle, woi^nt, Mg (ton)
w - mean numh».:.c of wheels
p = njmber w! d^ys with ,*t least 0.15'« Dim
(0.01 in.; if precipitation pet year
The particle size ultiplier, k, in Equation 1 varies with aerodynamic, particle
size riingc ds lolluws:
Aerodynamic Part id« Sizo >'-,! I : ipl i i r i or i-'r,u;i': ioi
i <30 -m ] <'. 5 ra
0.8U
O.'.U
0.36
0 20
0.095
The vjmbor of wor tlsys pi?;- ye^ir, p, tor t*v ^.t^ographical area of interest
shoulr. l';B determined froia /.or-il cl'.aatic d.ita. Kigurt1 II. 2. 1-1 gives the geo-
graphical iiistrihuul.cn of rhtJ F^..MI annual natnbcr of (>it days per year in the
United States.
Equation 1 rotaino t'iv assigned quiiity rating it applied within the ranges
of source c-jndi':. Ions L''i,-it. were t>.>st-!d '. n developing tlic equation, .is follows:
RANGtb Or SO.RC.r, CON[>1TLONS FO? KQUAflON 1
Equat t:)n
KoaJ si).: 1
coir;*?1.!. 1 Mean vo'.iicl
(7,, v,/w) J Mg
4.3 - 2U '. 2.1 - 142
f
e weight
to-.)
3 - 157
Mean vehicle spe«;d
km/hr j iiiph
j ,. . .
21 - 6i i 13-40
i
Mean no.
of wheels
4 - n
Also, to repair, the quaMi;, rating of the equation applied tc a specific .jnpaved
road, it is nscestiry t'vit reliable correction parameter v.r.lutvs for the specific
road in cues"ion he dorrrmined. The field and laboratjry procedures for deter-
mii'.ng roaii aurf^c-.e s ', 1 1 content eirc. p,ivt-n in Reference 4. In the event that
dire s^ec fie values for correctioi parameters cannot be ob'.ain'id, the cippro-
prlar.e me.in value? frora T.^blu ll.?.l-i may be usc-d , but the q i-sllty rating of
the ecuati'in i -: tedncMd to B.
Equatic-r 1 wat, d«velopjd for calculation of annual avfira^e emissions, .ind
tuus, is to he multiplied by ar.nua 1 vehicle ilisr. i::r.e t. raveltc. (VUT). Annual
average vplues for «ach '*. f tht .-or c.jr. t ion par.amevers arc _o be substitutod into
•'i sec 1.
., Sourc«.""i
11.2.1-3
-------
in
I
4N
m
o
z
n
H
MlltS
01
Figure 11.2.1-1. Mean number (.f days with 0.01 inrh or more of prer ipit.itior in United States.
if.
-------
the equation. Worst case emissions, corresponding to dry road condition?,
nay be calculated by setting p • 0 In the equation (which is equivalent to
dropping the last term from the equation). A separate set of none 11 mar.ic
correction parameters and a higher than normal VDT value may also be justified
for the worst case averaging period (usually 24 hours). Similarly, rrc available and where
roads are confined to a single sit'j, euch as a construction location.
9/85 Miscellaneous Sources 11.2.1-5
-------
References for Section 11.2.1
1. C. Cowherd, Jr., et al . , Development of Emission Factors for Fugitive
Dust Sources, EPA-450/3-7 t-037 , U. S. Envl ronmental Protection Agency,
Research Triangle Park K:, June 1974.
2. R. J. Dyck and J. J. Stuk;3 , "Fugitive Dust Emissions from Trucks on
Unpaved Roads', Envi/onme'itai Science and Technology , 1£(10) : 1046-1G48,
October 1976.
3. R. 0. McCaldin and K. J. leidel, "Particular*! Emissions from Vehicle
Travel over Unpaved Roads', Presented ac the 7lst Annual Meeting of the
Air Pollution Control Asat elation, Houston, TX , June 19/8.
4. C- Cowherd, Jr., et al^, Iron and Steel PlanU Open Dust Source Fugitive
E'jisgion Evaluat ion , EPA-6DO/2-79-1Q3, uT S. Environmental Protection
Agency, Research'lrlangle Vark, NC, May 1979.
5. R. Bohr, et a 1^. , Fugitive Emissions from Integrated Iron and Steel Plants,
EPA-600/2-78-050, U. S. Environmental PrcTtection Apency, Research Triangle
Park, NC, March 1978.
6. R. Bohn, Evaluation of Open Dust Sources in the Vicinity of Buffalo, New
York, U. S. Environmental Protection Agency, K?w York, NY, March 1979.
7. C. Cowherd, Jr., and T. Cuscino, Jr., Fugitive Emissions Evaluation,
Equitable Environmenta L Health, Inc., F.lmhursf, IL, February 1977.
8. T. Cuacino, Jr., et ai. , Taconite Ml.:ing Fugitive Emissions Study,
Minnesota Pollution f.ontrol Agency, Rocevillc MN, June 1979.
9. K. AxetelJ. and C. Covi'.trd, Jr., Irrproved Emission Farcers for Fugitive
Dust fron Western Surface Coa_l_ Mini_ng JSources 2 Volumes, EPA Contract
No. 68-03-:29T4ri>EDCo~ Environmental, lr,"7, Kansas City, to, July 1981.
10. T. Cuscino, Jr., £t_al_._, Iron and Steel Pl/»nt Open Source Fugitive
Emission Control Evaluatioii, EPA-60C-7T- 33-1 10 , U. S. Environmental pro-
tection Agency, Research Triangle Fark, NC, October 198;).
11. J. Patrick Rei-Jer, Slze_ S^pecific Emission Factors for Uncontrolled Indus-
trial and Kur.jtl Roads , EPA Contract No. 68-02-3158, Midv-est Research
Ins'titute, Kansas City, MO, Sepr. tir.be r 19h3.
12. C. Cowherd, Jr., a.id P. Em-ltjhart, Size SpeL-.\£ic Particulars Emission
Factora for ludustrial and _R_ura_i Roado. EP(\-
-------
; 1.2.2 AGRICULTURAL TILLING
11.2.2.1 Ger.v-rai
The two universal objectives of agr> cul tur il t.illing -ire the creation
of the desireu soil structure to be u^ed as the crop seedhed and the eradi-
cation of werds. Plowing, tiie most conuion method (if til'agp. consists of
some farm of tutting l^-ose, granulating ,-ind inverting the soil, an-l turning
under the organic litter. Implements that loosen I he soil an.1 cut oif the
weeds but le,ive tlie surfer? trash ii. place Lave recently brcome mc-e popu-
lar for tilling in dryland fanning ;-nnas.
During a tilling operation, dust particles from the loosening and pul-
verization of the toil aie injected into the atmosphere as the soil is
dropped to the surface. Dust emissions are greatest during periods of dry
soi i and during final seedbed preparation.
11.2.2.2 Emissions and Correction Parameters
The quantity of dust from agricultural tilling is proportional to the
area of land tilled. Also, emissions depend on surface soil texture and
surface soil moisture cement, conditions of a particular field being
tilled.
Dust emissions from agricultural tilling ha- e been found to var> di-
rectly with the silt content (defined as particles < 75 micrometers in di-
ameter) of th;> surface coil depth (0 to 10 on [0 to 6 in.]). The soil silc
content is del (.-mined by measuring the proportion of dry soil that, passes a
200 mesh screen, using ASTH-C-136 method. Note that this dfTini-ion of
silt differs i'rom that customarily used by soil scientists, for whom silt.
is particles from 2 to 50 microim-tors in diameter.
Field measurements'2 indicate that dust emissions J'rom agricultural
tilling are not significantly related to surface soil inoisture, although
liuited earlier data had suggested such a dependence.1 This is row be-
lieved to reflect the fact that: most tilling is performed nnd?r dry soil
conditions, as were the majority of the iield i
Available test daia indicate '.to substantial dependence of emissions on
ihe type of tillage iirplemt-.it, ii operating Jt a typical speod (for ex^in-
^le, 8 to 10 kra/hr [5 to 6 mphl).1"2
11,2.2.3 Predictive Emission Factor Equation
The quantity of <'L.;JI einis.-,; ns from agr i nil tural tilliug, per acre of
land tilled, may be ^s't iinaUid with a rating of A or ti (set bclov) vising the
following empirical express i on* :
E •- K(S.JH)is)° (kg/hectare) (1)
F. = HA.bO>s)°'6 (Ib/acre)
5/33 Hiscel laneous Sources 11.2.2-1.
-------
where: E ~ emission factor
k = particle size multinler (dimensionless)
s = silt content of surface soil (%)
The particle size multiplier (k) in the equation varies with aerodynamic
particle size range as follows:
Aerodynamic Particle Size Multiplier for Equation 1
Tot^l
particulate < 30 pm < 15 Mm < 10 jjm < 5 \Jm < 2.5 urn
1-0 0.33 0.25 0.21 0.15 0.10
Equation I is rated A if used to estimate total particulate emissions,
and B if used for a specific particle size range. The equation retains its
assigned qual^jy lating if applied within tiie range of surface roil silt
content (1.7 to 88 peri-ent) that was tested in developing the equation.
Also, to retain the quality rating of Equation ] appliei to a specific ag-
ricultural field, it is necessary to obtain a reliable silt value(s) for
that field. The sampling and analysis procedures for determining agricul-
tural silt content are given in Reference 2. In the event that a site spe-
cific value for silt content cannot be obtained, the mean value of 18 per-
cent may be used, but the quality rating of the equation is reduced by one
level.
V
11.2.2.4 Control Methods3
In general, control methods are not applied to reduce emissions from
agricultural tilling. Irrigation of fields before plowing will reduce
emissions, but in maiy cases, this practice would make the soil unworkable
.n.nd would aversely affect the plowed soil's characteristics. Control
methods for agricultural activities are aimeJ primarily at reduction of
emissions f^om wind eiosion through such practices as continuous cropping,
stubblp mulching, strip cropping, applying limited irrigation to fallow
fields, building windbreaks, and ui^ing chemical stabilizers. No data are
availabl" to indicate the effect." of these or other control methods on
agricu'-tural tilling, but a:; a practical matter, it may be assumed that
emission reductions are not significant.
References for Section 11.2.1.
1. C. Cowherd, Jr., et u.l. , Development of Emission Factors f?r_ Fugitive
I'Ilst_5£Lirc_es, EF\-450'3-74-037, '•]". S. Fnvironmentai Protection Agency.
Research Triangle Park, NC, june 1974.
2. T. A. Cuscino, Jr., et al. , The Kc'le of Agricultural Practices in
fugitive Dust Emissions, California Air Resources Doa/d, Sacramento,
CA,"lune 1981.
3. G. A Jutze, Pt_aj_., Investigation of Fugitive Dust - Source^ Enussions
And Control. 'EPA-450/3-7^-036a. 1). S. Environmental Protection Agency,
Research Triangle Park, NC, Jine 1974
11.2.2-2 F.MISSIOh FACTORS 5/33
-------
11.2,3 AGGREGATE HANDLING AMD STOOGE PILES
11.2.3.1 General
Jnheteut in operations that use numerals in aggregate torn is the
maintenance of outdoor stoiage piles. Storage piTes are usually left un-
covered, partially because of the net d for frequent material transfer into
or out of storage.
Dust emissions occui at several points in the storage cycle, duriig
material loading onto the pile, during disturbances by f.trong wind cur-
rerits, and during ioadout frt<« the pile. The movement of tracks an4 load-
ing equipment in the storage pile area is also a substantial source of
dust .
11.2-3.2 Emissions and Correction Parameters
The quantity of dust emissions from aggregate storage operations var-
ies with the volume of aggregate passing through the storage cycle. Also,
emissions depend on three correction parameter* that chaiacterize the con-
dition of a particular storage pile; ?ge of the pile, moisture content and
proportion of aggregate fines.
tfhr.n freshly processed aggregate is loaded onto a storage pile, its
potential for dust emissions is a*: a maximum. lines are easily disaggre-
gated and released to the atmosphere upon exposure to air currents from ag-
gregate transfer itself or high winds. As the aggregate weathers, how-
ever, potential for dust emissions i:i greatly reduced. Moisture causes ag-
gregation and cementation of fines to th-2 surfaces of larger particles,
Any significant rainfall soaks the interior of the pil-, and the drying
process is very slow.
Field investigations have shown t,hdt emissions from aggregate
operations vary in direct proportion to the percentage of silt fparticies
<-' 75 l^m in ciiineter) in the aggregate material.1 3 The silt content is de-
termined by measuring the proportion of dry aggregate material that passes
through a 200 mesh screen, using Ab'lM-C-136 method. Table 11.2 3-1 summa-
rizes measured silt and moisture values for industrial aggregate materials.
11.2.2,3 Predictive Emission Factor Equations
Total dust emissions croin aggregate storage piles ari> cont :ihutioas of
several distinct yource activities within the storage <~ycle:
1, Loading of aggregate onto atorage piles, (batch or continuous drop
operations) .
2. Equipment trafii ; in storage; area.
3. Wind erosion of pile surfaces and ground areas around piles,
** , Loadout o( aggregate for sbi^mecic or for return to the procest
stream (batch or continuous drop operations).
5/33 Miscellaneous Sources 11.2,3-1
-------
M
\_^
I
TABU: 11.2.3-1. TYPICAL sii.r AND MOISTURE CONTENT VALUES
OK MATERIALS AT VARIOUS INDUSTRIES
Silt II)
2
00
C
•T^
H
§
CO
Jn«1ustrv Material No. r' -.r^t
samples Han^e
Iron and stfel
prod'irt ion TVllrl orr 10 1.4 - 13
Uimp on- 9 2.R - 19
Coal 7 1 - I 1
S\n', 3 1-7.1
1- inc dnsl J ;4 - ?3
Cok" bmpzc 1
Bl-'i-.iic-d nr«- I
Sinler 1
l.imrslonr 1
Sl'iii-: iiiiarryiiiR ^
and processing O .si cH linii'Stonf1 / 1 1 - 1.1
T.TI nr l ' r mirinR
and p.-oressinj,' Prllpts 9 7.2 - S.A
T.i "'i.iRs 2 N\
S«r!;((lrn <;ill'l;ire
. d toa'. IS 3 .'. - 16
tnal ni n: ne , . ,_ , „ ,r
* Ovrrnurdrn IS 3.8 - Ij
F.xpr^o ,ro«nJ 3 ', 1 2 1
5r)eipnCfK 2-S. NA ~ not applir.ihle.
ii f »
R»' fprrnrr b .
1 Si'^rfncp 7 .
Nc?. ni T(
^^^*<^^ S flinp I f*.
4.9
9.5 f>
'j h
S.3 ]
I8.'i 0
i 4 1
ISO 1
0 / 1)
0 . 1, !»
1.6 7
.».'. 7
II. 0 1
6.2 7
7 . •) 0
IS.O 3
r-5(
F RXiRr Mean
0 b'. J S 21
16-8.1 5 . '»
2.S - M ^.8
n 2r> - 7.2 0.97
N* NA
6.4
6.6
N/I NA
NA NA
01-11 07
<1 OS - 2. ) 0.96
0.3S
2.8 - 70 6.9
NA MA
0.0 - 6.4 1.4
>J-
ex
-------
Adding aggregate material to a storage pile or removing it usually in-
vol< es dropping the mate-rial onto a receiving surface. Truck duwpiug on
the pile or loading out from the pile to a truck with a front end loader
are examples of batch drop operation. . Adding material to the pile by a
conveyor stacker is an example of a continuous drop operation.
The quantity of particuiate emissions generated by a batch drop opera-
tion, per ton of material transferred, way be estimated, with a rating <-f
C, using the following empirical expression2:
i) ML) ML)
£ = k(0.00090) / \2.2. Vl.5/ (kg/Mg) (1)
(S) (A
E = k(0.001S) x V n,, (Ib/ton)
fc / lr t U « J*3
(!) (i
where: E - emission factor
k - particle size multipler («'itnensionless)
s = material silt content (%)
U = mean winrl speed, m/s (mph)
H = drop height, -n (ft)
M = material moisture content (%)
Y = dumping device capacity, m3 (yd^)
The particle size raultipler (k) for Equation 1 varies with aerodynamic par-
ticle size, shown in Table 11.2.3-2.
TABLE 11.2.3-2. AERODYNAMIC PARTICLE SIZE
MULTIPLIER (k) FOR
EQUATIONS 1 AND 2
Fquation < 30 < Ib < 10 < 5 < 2.5
Batch drop 0.73 0.48 0.36 0.23 C.13
Continuous
drop 0.77 0.49 0.37 0.21 0.11
The quantity of particulate emissions generate^ by a continuous drop
operation, per ton of material transferred, may be estimated, with a rating
of C, using the following empirical expression3:
5/33 Mifcel! antnus Sources 11.? 3-3
-------
E = k(0.00090)
E = k(.0.00l8)
(i) (JL) (JL\
\5/ \2.2/ \3.0'
(§)
(Vg/Mg)
(2)
(!) (?)
(Ib/ton)
where: E = emission factor
k = particle size multiplier (dimensLoui»ss)
s = material silt Lontent (%)
U - mean wind speed, m/s (a.ph)
H = drop height, IP (ft)
H = material moisture content (%)
The particle size multiplier (k) for Equation 2 varies with aerodynamic
particle size, as shown in Table 11.'..3-2.
Equations 1 and 2 retain the assigned quality rating if applied within
the ranges of source conditions that were tested in developing the equa-
tions, as given in Table 11.2.3-3. Also, to retain the quality ratings of
Equations 1 or 2 applied to a specific facility, it is necessary that reli-
able correction parameters be determined ior the specific sources cf inter-
est. The field and laboratory procedures for aggregate sampling are given
in Reference 3. In the event that site specific values for correction pa-
rameters cancer be obtained, the appropriate /scan values from Table
11.2.3-1 ma\ be used, but in thit case, the quality ratings of the equa-
tions are redrced by cne level.
TABLE 11.2.3-3.
RANGES OF SOURCE CONDITIONS FOR
EQUATIONS 1 AND 2a
Equation
Silt
content
Moisture
content
Dumping capacity
10? yda
Drop height
m ft
Batch drop 1.3 - 7.- 0.25 - 0.70 2.10 - 7.6 2.75 - 10
Conti nuous
'irop
1.4 - 19 0.64 - 4.8
NA
NA
NA
NA
1.5 - 12 4.8 - 39
NA = not applicable.
For emissions fron equipment trafiic (trucks, front end loaders, doz-
ers, etc.) traveling between or on piles, it is recommended that the equa-
tions fo- vehicle traffic on unjj^vod surfaces be used (see Section 11.2.1).
For vehicle travel between storage piles, the silt value(s) for the areas
11.2.3-4
EMISSION FACTORS
5/83
-------
among the piles (whinh may differ from the silt values for the stored mate-
rials) should be used.
For emissions from wind erosion of active storage piles, the following
total suspended particuldte (TSP) emission factor equation is recommended:
E = '•' (iTi) (T!?) (if) CkS/'iay/hectare) (3)
E ' '•' (A) (llr) (if)
where- £ = total suspended particuiate emission factor
s = silt conteut of aggregate (%)
p = number of days with £ 0.25 nun (0.01 in.) of precipitation
per year
f = percentage of tiro*; thf.t the unobstructed wind speed ex-
ceeds 5.4 m/s (I'i mph' at the mean pile height
The coefficient in Equation 3 is taken from Reference 1, based on sam-
pling of emissions from a sand and gravel storage pil* area during periods
when transfer and maintenance equipment waj not operating. The factor from
Test Report 1, expressed in jtass per unit area per day, is more reliable
than the factor expressed ir. mass per unit mass of material placed in stor-
age, for reasons stated in that report. Note that the coefficient has been
halved to adjust for the estimate that the wind speed through the emission
layer at the test site vas one half of the value measured above the top of
the piles. The other cerms in this equation were added *.o correct fot
silt, precipitation and frequency of high winds, as discussed in Refer-
ence 2. Equation 3 is rated C for application in the sand and gravel in-
dustry and D for other industries.
Worst case emissions from storage pile areas occur under dry windy
conditions. Worst case emission;; from materials handling (bitch and con-
tinuous drop) operations may be calculated by substituting into Equations 1
and 2 appropriate values for aggregate material raoislure content and for
anticipated wind speeds during the worst case averaging period, usually
24 hours. The treatment of dry conditions for vehicle traffic (Section
ll.Z.lj and fjr wind erosion (Equation 3), centering around parameter p,
follows the Methodology described in Section 11.2.1. Also, a separate srt
of nonclimatii- correction parameters and source extent values corresponding
to higher thf.n normal storage pile activity mav be justified for the worst
case averaging period.
11.2 3.4 Co'.nrol Methods,
Water:. ng and chemical wetting agents are the principal means for con-
tro1 of ^gregate storage pile emissions. Enclosure or covering of in-
active piles to reduce wind erosion can also reduce emissions. Watering is
useful mainly to reduce emissions from vehicle traffic in the storage pile
are?. Watering of the storage piles themselves typically has only a very
temporary slight, effect on total emissions. A much more effective tech-
nique is to apply chemical wetting agents for better we^.tin? of fines and
5/83 Miscellaneous Sources 11.2.3-5
-------
longer retention of the noisture film. Continuous chemical treatment of
material loaded onto piles, coupled with watering or treataent of roadways,
can reduce total particulate emissions from aggregate storage operations by
up to 90 percent.
References for Section 11.2.3
1. C. Cowherd, Jr., et al . , Development of Eminion Factors for Fugitive
Dust Sources, EPA-450/3-74-037, U. 3. Environmental Protection Ag-.ncy,
Research Triangle Park, NC, Jime 3974
2. R. Bohn, e t a 1 . , Fugitive Emissions from Integrated Iron and Steel
Plants, F.PA-6QO/2-7B-050, U. S. Environmental Protection Agency,
Research Triangle Park, NC, March 1?78.
3. C. Cowherd, Jr., et al. , Iron anJ Steel Plant Open Dust Source Fugi-
tive Emission Evaluation, EPA-600/2-79-103 , U. S. Enviror,i,antal Pro-
tection Agency, Research Triangle Park, NC, May 1979.
4. R. Bohn, Evaluation of Open Dust Sources ia the Vicinity of Buffalo,
New York, U. S. Environmental Protection Agency, New York, NY, March
5. C. Cowherd, Jr., and T. Cuscinc, Jr., Fugitive Emissions Evaluation ,
Equitable Environmental Health, Inc., lllmhuist, IL, February 1977.
6. T. Cuscino, ct al., Taconite Mining Fugitive Emissions Study,
Minnesota Pollution Control Agency, Rofeville, MN, June 1979.
7. K. AxeLell and C. Cowherd, Jr., I rop rove d Emission Factors for Fug i t i v 5
Dust from Western Surface Coal Mining^ Sources , 2 Volumes, EPA Contract
No. A-03-2924, PEDCo Environmental, Inc., Kansas City, MO, July 1981.
8. G. A. Jutze, et «tl . , Investigation of Fugitive Dust Sources Emissions
and Control, EPA-4bO/3-74-036a, U. S. Environmental Protection Agency,
Research Triangle Park. NC, June 1974.
11.2.3-6 EMISSION FACTORS 5/83
-------
1 1 .2.4 Henvy Construction Operations
1 1 .2.4.1 General - Heavy construction is a source of Just emissions that may have substantial icmporjry impact
on local air quality. Building and road const rii. -tion are the prevalent construction categories with the highest
emissions potential. Emissions 'luting (he cor.itu.'clion of u building or ro^d are associa^d w.ih Ir.nd clearing,
blasting, ground excavation, cut and fJl uper.ilioiis. and the construction ut the particular fjcilily iis.-lf. Dust
emissions vary substantially from day to uay depondii.g on ;he level of activity , t'ne specific opfations, and ;he
prevjjljng weather. A large portion of the emissions resell from equipment traffic over 'cmporary toads ut ^i.e
construction s le.
I 1 2.4.2 r.m isions and Coriecnori Parameters The i|u.miii\ of dust emissions from con, unction operation*
are proportk nal to Ihe area of lard being woiked and the level ut construction activity AJst , by analogy to the
parameter dependence observed for other sirnilai fugitive dust sou'ces,1 it is probable that emissions from heavy
construction operations are directly proportional to the silt content of the soil (thai is. particles smallei than 75
jjm in diameter) and inversely proportional 10 the square of the soil moisture, as r.-pressmed by Thornthwaite's
precipitation-evaporation (PF) index.2
11.2.4.3 emission Facloi — Based on field mtasuremetas of suspended dust en, sterns ti TTI ipvtment and
shopping cen'ei construction projects, an approximate en-.ission Factor lor construction o| Buttons is:
1.2 tons p;i 'icre of construction per moiiih ol 'activity
This value applies lo construction opeiY
si/.e for me capture of const met ion dust by a standard high-volume filtration samplei1, based 0,1 a pattici-
density ol 2.0-2 " g/cmj.
11.2.4.4 Control Methods Watering is nv--,; uftjr. sc'lect^u as a onirol methocl because water a-id necessary
equipiTien1. are usually available at construction sik'v The elloctiveness uf watering lot control depends grejily on
the frequency of application. An effective watoriii£ program (tlut :s, ,'*ice daily watennj; v*hi> complete
cuvcragf) is estirrutcO in reduce dust emissions h> up :o 50 percent,1 f hemicn! s'.jlili/.ition is not effective in
reducing the large portion of construction emissions caused b\ equipment traffic >r active oxcavatiun ; i-d tut :mJ
fill operations. C'hemical stabili/i'rs are useful p'inuiilv fin applicution on completed cuts 'jmi uiis A the
construction site. Wind eiosion ciiiissions froi-i inactive poiuons ol the construction sue ran be reduced b, about
^0 percent in this marner, but this repri-;»ms a lairly minor reduction in 'ot;il C'.Missioni >.otnj>;red w-.ih ('missions
occurring during a period of high activity.
References for Section \ 1 .2.4
1. '"o* herd, ('., Jr., K. Axe;ell, Jr., ('. M. (iufiiilu'r , .iivl li A. Ju:/.e. Dexclopmrnt ' I missions I'icior: ' >i
Fugitive Dust Source?. Midwest Kescaich Institut'.-, Kansas C'liy. Mr,. Piepureu for l.-.r-.vimnmi.-ntal Protectu n
Agency, Resea.ch Triangle Park, N.C. under C.)iiiiuct So. hH-OJ 0(.!4. PMhlnaiion No. I:P V450/..V74-037.
lune 1974.
2. Thuruthwaite, C. W. C'limaies ol Nor.h Amcricj As coding in j New C'h'tsifkaiion. Cn og-aph. Rev. 21
3. Jut/c, (> A, K Axetell. Jr., and W. Parkfi Invostiijaiioii <>i Kimiiive llust -Sources l-mi«sio.iS ;nu! ( rntiol.
I'l-.lX i) t.nvironrnental Specialists. Inc.. C'lncirmatl, Oliji Piepaied lot liiiviioiin:e:itai Prott,l,i:i Agency,
Hex-arch Triaia-le I'ark, N.C. under Contract No. (vS.02-()044. Publrcalim No tPA-45u/3-74-03hi'. June IV/4.
12/75 Miscolhiiieoits Sources 11.2.4-1
-------
11.2.5 PAVED URBAN ROADS
11.2.5.1 General
Various field studies have indicated that dust emissions l rom paved street
are a major component of the material collected by high volume samplers. Reen-
tr=>.infcd traffic dust has been found to consist primarily of mineral matter
siviJlar to couuaou sand and soil, mostly tracked or deposited onto the roadway
by vehicle traffic itself. Other paniculate matter is emitted direcLly by the
vehicles from, for example, engine exhaust, wear of bearings and brake linings,
and abrasion of tires against the read surface. Some of these direct emissions
may settle to the street surface, subsequently r.o be reeutralred. Appreciable
emissions from paved streets are added by wind erosion when the wind velocity
exceeds a threshold value of about 20 kilometers per hour (1? aii.es per h<.ur).
iigure 11.2.5-1 illustrates particulate transfer processes occurring on urban
streets.
11.2.5.2 Emission Factors And Correction Parameters
Dust emission rates nay vary according to a number of factors. The most
important are thought to be traffic volume and the quantity and particle size
of loose surface material on the street. On a no-mal pave<-i street, an equili-
brium is reached whereby the accumulated street deposits are maintained at a
relatively constant level. On average, vehicle carryouc from unpaved areas
may be the largest single source of street deposit. Accidental spills, street
cleaning and rainfall are activities that disrupt the street loading equili-
brium, usually for a relatively short duration.
The? lead content of fuels also becomes a part of rtentralned dust from
vehicle traffic. Studies havt- found tha*., for the 1975-76 sampling period,
the lead emission factor for this source was approximately 0.03 grans per
vehicle mile traveled (VMT). With the reduction of lead in gasoline and the
use of catalyst equipped vehicles, the lead factor for reentrained dusi was
expected to drop below 0.01 grama per mile by 1980.'
The quantity of dust emissions of vehicle tr:;f(ic on a pav-rd roadway may
be estimated using the following empirical express.! ori1 :
e = k /St_\ ? (t;/VKT)
(Ib/VMT)
where: e - particulate emission factor, g/VKT (Ib/VMT)
L = total road surface dust loading, g/m2 (graina/ft2)
s = surface silt content, fraction of particles
< 75 -jm diameter (American Association of
"State Highway Officials)
k «= base emission factor, g/VKT (Ib/VMT)
p « exponent (dimensionluss)
9/85 Miscellaneous Sources 11.2.5-i
-------
DEPOSITION
LJl
I
IO
in
Tl
O
H
O
T) PAVEMENT WEAti AND OfCDtfP05!Tpa«
(2) VEHICLE RELATEDDF»OkJV fl»
3) 3USTFALL
4 UTTER
MUD AMD DIRT CAHRYOUT
S) EROSION FROM ADJACENT AREAS
7) SPILLS
8) 6IOLOCICAL DEBRIS
?) ICE CONTROL CO.MFOUNOS
VD
Ul
--•'—
j)i- ,«.-*; -ff'
-1. Deposition and removal processes
:RLMCVAL
(7] REENTRAINMENT
[Tj WINOEffOSION
(Tj
[TJ RAINFALL HUSQFF T3 CATCH BASIN
(T) STREET SWEEPING
-------
The total leading (excluding llcter) is measured by sweeping and vacuuming
lateral strips of known area from each active travel lane. The silt fraction
Is deternined by measuring the proportion of loose dry road dust that passes a
200 me.sh screen, using the ASTM--C-136 method. Silt Loading is the prodjct of
total loading and silt concent.
The base emissio" factor coefficients, k, and exponents, p, in the equation
for each size fraction are listed in Table 11.2.5-1. Total suspended particulate
(TSP) denotes that particle siz" fraction of airborne particular matter thac
would be collected by a standard high volume sampler.
TABLE 1) .2.5-1. PAVED URBAN ROAD EMISSION FACTOR EQUATION PARAMETERS3
Particle Size Fraction^
TSP
< 15 vril
1 10 Um
£2.5 )jn
k
g/VKT (Ib/VMT)
5.87 (0.0208)
2.54 (0.0090)
2.28 (0.0081)
1.02 (0.0036)
J.
0.9
0.8
0.8
0.6
Reference 4. See page 11.2.5-1 for equation. TSP • total suspended
paitlculate.
aerodynamic diameter.
Microscopic analysis indicates the origin of material collected on high
volume filters to be aboi't '40 weight percent combustion products iind 59 per-
cent mineral mattjr, with traces of biological matter and rubber tire particles.
The small particulate is mainly combustion products, while most of the large:
material is of mineral origin.
1.1.2.5.2 Emissions Inventory Applications*
For most emissions inventory applications involving urban paved roads,
actual measurements of silt loading will probably not be made. Therefore, to
t.ir;ilitatc the UE.I of the previously described equation, it is necessary to
characterize silt: loadings according to parameters readily available to per-
sons developing 'ite Inventories. It is convenient to characterize variations
in silt loading with a roatiway classification system, and this Is presented
in Table 11.2.5-2. This system generally corresponds to the classification
systems used by transportation agencies, and thus the data necessary for an
emissions Invpntor/ - number of road kilometers per road category and traffic
councs - should be easy to obtain. In SOBX-. situations, it. may be necessary to
combine this silt loading information with sound engineering judgment la order
to approximate the loadings for roadway types not specifically included In
Table 11.2.5-?.
Miscellaneous I'.ourcas
11.2.5-3
-------
TABLE 11-2.5-2. PAVED U3BAN ROADWAY
Roadway Category
Freeways/ express ways
Major streets/highways
Collector s'.reet-;
Locil streets
Average Dally Traffic
(Ve'nlcle-s)
> 50,000
> 10,000
300 - 10,000
< 500
Lanes
>_ -'*
> 4
2b
2C
fReference 4.
°Road width ^32 ft.
cRoad width < .32 ft.
A data base of 44 simples analyzed according to consistent procedures nay
be used to characterize the silt loadings for each roadway category.4 Theise
samples, obtained during recent field saupiing programs, represent a broad range
of urban land use and roadway condition?. Geometric means for thir data set are
given by sampling location and roadway category In Table 11.2.5-3.
TABLt. 11.2.5-3. SUMMARY OF SILT LOADINGS (sL) FOR PAVED URBAN ROADWAYS-
Roadway
Local Collector
Stireeta Streets
X (g/ra2) n X (g/m2)
o &
Baltimore 1.42 I 0.72
Buffalo 1.41 5 0.29
Granite City (IL) -
Kancaa City - - 2.1]
St. i-ouis -
A.I 1.41 7 0.92 1
Category
Major Streets/
~ Highways
n Xg (g/-22) n
4 0.39 3
2 0.24 4
0.82 3
4 0.41 :.3
0.16 3
0 0.3* 26
Freeways/
Expressways
V*'-2> •
-
_
-
_
U.022 1
0.022 i
aReference 4. Xg ™ geometric mean baaed ori cor c<. spondino n sample s'.ze.
Dash • not available. To Convert g/m2 to gra.'ns'fL2 multiply g/m2 by l.-«337.
ii.2.5-4
EMISSION FACTORS
9/8:
-------
These sampling locations • ar DC considered representative of most large
urban areac In the United Stales, with rhe possible exception of those in the
Southwest. Except f c r th*- collector roadway category, the mean silt loadings
do not vaiy greatly from city to city, though the St • Louis mean for major
roads id come what lover than those of the other four c.'tieti. TVie substantial
variation within the collector roadway category ts probably attributable to the
effects, 01 land use around the specific uampling locations. It should also be
noted that an examination of d?ta collected it three cities in Montana during
early sprang indicates th.it winter road sard ing may produce loadings five to
si?: tines higher than the means of the leadings given in Table iJ.2.5-3 for th
respective road categories. s
11. 2. 5-4 presents the emission factors by roadway category and par-
ticle size. These were obtained by inserting the abt-ve mean silt loadings into
the f.cuati^n on page 11. 2. 5-1. These emJeslon factor's can be used directly for
[.any emission inventory purposes. It is important to note that the paved road
emission factors tor T5F agree quite wall with thoce developed from previous
testing of roadway Bites in the major street and highway category, yielding
mean TSP collar, ion factors of 4.3 grams/VKT (Reference o) and 2,6 grp.ms/VKT
(Ref jrence 7) .
TABLE 11.2.5-4. RECOMMENDED PART1CULATE EMISSION VACTORS FOR SPECIFIC
ROADWAY CATEGORIES AND PARTICLE SIZE FRACTIONS
Emission Factor
Roadway TSP < 1? vn £ 10 urn <_ 2,5 urn
Category _ _ ___ ___ ___ __ ___ _
___ g/VKT (IbTViMT ) gTvKT (lh/VMT7 g/VKT (l^VMT) g/VKT (lb/VMTT
Local streets 15 (0.053) 3.b (0.021) 5.2 (0.018) 1.9 (0.0067)
Collector
streets 10 (0.035) 4.1 (0.015) 3./ (C.CJ13) 1.5 (0.0053)
Major
highways 4.4 (0.016) 2.0 (0.0071) 1.8 (0.0064) 0.8', (0.0030)
Frer ways/
expressways O^f* (D.0012) 0.21 (0.00074) 0.19 (0.00007) 0.16 (0.00057)
ReferenceH for Section 11.2.5
1. D. R. Dunbar, R^auspension c<£ Particulate Matter, EPA-450/2- 76-C31 , U. S.
Environmental Protection Agency, Research Triangle Parks NC, March 1976.
1. M. P. Abel, "The Impact of Ref loatation on Chicago's T^tal Suspended
Leve.lr»", Purdur University, Purdue, IN, August
3. C. M. Maxwell s-.id D, W. Nelson, A Lead EmiBBion Factor for Reentrained
Dust f^oni * Paved Roadway, EPA-450/3-78-021, U. S .~ Environm«nt,-.l Pro-
tection Af-ency. Ke;,earch Triangle Pack, NC , Airil 1978.
9/85 Miscelleanous Cources 11.2.5-5
-------
Chatten Cowherd, Jr. and Phillip J. Englehart, Paved Road Particulate
EPA-600/7-84-077, U. S. Environmental Protection Agency, Wash-
ington, DC, July 1984.
5. R. Bohn, Update and Improvement of the Emission Inventory for MAPS Study
Ar_ea8_, State of Montana , Helena, MT, August .1979.
6. C. Cowherd, Jr., et al., Quantification ot Dust Entrainnenr fram Paved
C. Cowherd, Jr., et al., Quantifi
Roadways, EPA-A50/3-77-027, 1. S.
Envlronraental Protection
Research Triangle Park, NC, July 1977.
7. K. Axe tell and J. Zell, Control of Reentrainei Dust from Paved Streets,
EPA-907/9-77-077, U. S- Environmental Protection \gency, Kansas City,
MO, August 1977.
11.2.5-6 EMISSION FACTORS 9/85
-------
H.2.6 INDUSTRIAL PAVED ROADS
11.2.6.1 General
Various field stddies have Indicated thai dust missions from Industrial
paved roads are a major component of atmospheric pan Iculate natter in the
vicinity of industrial operations. Industrial traffic dust hat, been found to
consist primarily of mineral matter, most1./ tracked o.- deposited anto the
roadway by vehicle traffic Itself when vehicles enter from an unpaved area or
travel on the shou.lder of the road, or when material is spilled onto Lh-j paved
surface from haul truck traffic.
11.2.6.2 Emissions And Correction Parameters
The quantity of dust emissions from a givt.-n segment of ^ai. "•
'7 (iwvm)
) (if)
where: E = emission factor
1 =• industrial augmentation factor (din-ensionlesa) (see below)
n = number of traffic lanes
s =• surface material silt concent (%)
L - surface dust loading, kg/km (Ib/mile) (sec below)
W • average vehicle weight, Mg (ton)
9/85 Miscellaneous Sources 11.2.6-1
-------
TABLE 11.2.6-1. TYPICAL SILT CONTENT AND LOADING VALUES FDR PAVED ROADS
AT TNDUSTRIAL FACILITIES3
No. ot
Ho. of Mo. ct Silt (1. «/«•) Truv.,1 Tolil .
Induic-y Plant Silts Suplcj Range H«an UIKJ Rang.
COBMC utltlns 1 3 (1S.4-2I.7J (H.OJ 2 I12.9-19.SJ
l«b. 8-69.2)
Iron and tleel 2 0. 006-4. ?7
oroductlwi 6 zr l.l-'-S.7 12. S 2 U.02U-16.9
A.i,h.lr b«tct.ln« 1 4 [:.6-4.t)| (J.b) , 112.1 18.0)
Conccet* bat Chios 1 5 (5.2-6.0) |S.SJ ' [1. »-l .»)
[i.O-f.4]
Sana «n.1 §.-»vtl
DToctnlni 1 3 6.4-7.9] I'.IJ » l2.8-5.il
IS. 9-19. 4)
Silt loading
.•fun Unltl0 Hinge
[15.9] kt/ka [18S-40C]
0.495 kg/kn <1.0-2-3
i.75 Ib/nl
(15.7) kl/kj. [76-1931
(1.7) k«/k> 111-12)
(5.7; lb/Kl
|3.H) kF7lui 153-9'j)
S13.3) lb/«l
MKID
[2921
7
(131)
(1Z|
l'0|
1-i. '»i>ckr[t IndUats Mlutc k««»d on iapl«i obtained it onlr Dn«- pl»at >Ui.
^Multiply enirlei t 1,000 tu obttln it«ttd unlti-
The industrial road augmentation factor (I) in the Equation 1 takes Into
account higher emissions from industrial roads than from urban roads. 1-7,0
for an industrial roadway which traffic enters from unpaved areaa. ! - 3.5 for
an industrial roadway with unpaved shoulders where 20 percent of the vehicles
are forced to travel temporarily with otic set of wheels on the shoulder. I = 1.0
for cases iu which traffic does not travel on unpaved areas. A value between 1.0
and 7.0 which best represents conditions for paved roads at a certain industrial
facility should be used for I in the equation.
The nquatJ.on retains the quality rating of B if applied to vehicles
traveling entirely on paved surfaces (I = 1.0} and if applied within the range
of source conditions that vert: tested in de/tioping the equation as follows:
Sj.lt
content
(*>
5.1 - 92
Surface loading
kg/km H
42. 0 - 2,000
Ib/miJe
149 - 7,100
No. if
lanes
2-4
Vehicle
Mg
2.7 - 12
weight
tor.s
3-13
If I is >1 0, the rating of the equation drops to D because of the subjectivJty
in the guidelines for estimating I.
Tne quantity or fine particle omlssionn generated by traffic consisting
predominately of nvjdium ^nd heavy duty vehicles on dry industrial paved roads,
per vehicle vj.iir. of travel; may be estimated, with a 7-ating of A, using ":ne
11.2.6-2
EMISSiOn FACTORS
9/b5
-------
/„! \ C.3
E - > (~) (kg/VKT) (I,
BL\ °'3
.35J (lb/VMT>
where: E = emission factor
sL - road surface silt loading, g/m2 (oz/yd2)
The particle size multiplier (k) above varies with aerodynamic size r;inge
as follows:
Aerodynamic Particle Size
Multiplier (k) For Equation 2
(Uimenslotiless)
u <2.5 um
0.28 0.22 0.081
To determine participate emissions for a specific particle size ran^e, use the
appropriate value of k above.
The equation retains the quality rating oi A, if appliad within the range
of source conditions that were tested in developing the equation as follows:
silt loading, 2 - 240 s/m2 (0.06 - 7.1 oz/yd2)
mean vehicle weight, 6 - 42 Mg (7 - 4b tons)
The following single valued emission factors^ jiay be used in lieu of
Equation ° to estimate fine particle emissions t5enera'_ed bj light duty vehicles
on dry, heavily loaded industrial roads, with a rating ot i.':
Emission Factors For Light Duty
Vehicles On Heavily Loaded Roads
5 yra <10 ^n
0.12 kg/VKT 0.093 k.a;/VKT
(0.41 Ib/VMT) (0.33 Ib/VMT)
These cndssiori factors retain the assigned quality rating, If applied within
the range o[ source conditions Lhar. were tested in developing the factors t as
:
milt loading, 15 - 400 g/m2 (0.44 - 12 oz/yd2)
moan vehicle weight, <4 Mg (
-------
laboratory procedures for determining surtace material silt content and surface
dust leading are given in Reference 2. In the event that site specific values
ror correction parameters cannot be obtained, the appropriate mean values from
Table 11.2.6-1 may be used, but. tlie quality ratings of the equations should be
reduced by one level.
11.2.6.4 Control Methods
Common control techniques for industrial paved roads are broom sweeping,
vacuum sweeping aiid water flushing, used alone or in combination. All of
these techniques work by ieducing the silt loading on the t. aveled portions of
the load. As Indicated by a comparison of Equations 1 and 2, fine particle
emissions are less sensitive *A-;T. tcL..l buc.^..u;iil per*: initiate emissions to the
value of silt l^iding. Consistent with this, control techniques arc generally
lebs effective for the finer particle sizes-"* The exception is water flusning,
which appears preferentially to remove (or agglomerate) fine particles from the
paved road surface. Broom sweeping is generally regarded as the least effec-
tive of t'.ie common control techniques, because the mechanical sweeping process
is inefficient in removing silt from the road surface.
To achieve control efficiencies on the. order of 50 percent on a paved road
with moderate traffic ( 500 vehicles per day) requires cleaning of the surface
at least twice per week.** This is because of th« characteristically rapid
buildup of road surface material from spillage and the tracking and deposition
of material from adjacent unpaved surfaces, including the shoulders (berras) of
the paved road. Because industrial pa"ed roads usually do not have curbs, it
is Important that the width of the pavt-d road surface be sufficient for vehicles
to pass without excursion onto unpaved shoulders- Equation 1 indicates that
elimination of vehicle travel on unpaved or uncreated shoulders would effect a
major reduction in paniculate emissions. An even greater effect, by a factor
of 7, would result from preventing travel fron unpaved roads or parking lots
unto the paved road of interest.
References for Section 11.2.6
1. R. Bohn, et al., Fug i t i v <3 Emissions f rom Int.' g r a t e d I r o na nd Steel Plants ,
EPA-600/2-78-050, LJ. S. Environmental Protection Agency, Research Triungle
Pf>;k, NC, March 1978.
2. C. Cowherd, Jr., e t al., Iron and Steel PIan t_ Open Dust Source Fugitive
Em is si o n Eva 1ua 11on, EPA-600/2-79-103 , U . S. ETwifonmertaT Vrot e c 11 o r,
Agency, Research Triangle Park, NC, May 1979.
j. R. Bohn, Evaluation of Open Dust Sources :in the Vicinity of Buffalo,
New_York, U. S. Environmental Protection Agency, New York, NY, March 1979.
4. T. Case i no, Jr., et. al., Iron and Steel Plant Open Source Fugitive Emis-
sion Control Evaluation, EPA-faOO/2-83-110, U. S. Environmental Protection
Agency, Research Triangle Park, NC, October 1983.
5. J. Patrick Keider, Size Specific Pa_rticulate Emission Factors for Uncon-
trolled Industrial and Rural Roads, EPA Contract No. 68-02-3r58, Midwest
Research Institute, Kansas City, MO, Septwnbor 1983.
11.2.6-4 EMISSION FACTORS 9/85
-------
6. C. Cowherd, Jr., and P. Englehart, Sire Specific Particulate Emission
Factors for Industrial and Rural Roads, EPA-600/7-85-038, U. S. Envirun-
mental Protection Agency, Research Triangle Park, NC, September 1985.
9/85 Mlecellaneoua Sources 11.2.6-5
-------
1 / f-t
11.3.3 Emissions and Controls '
Carbon monoxide is *.he pollutant produced in greatest quantity from
explosives detonation. TNT, an oxygen deficient explosive, produces
more CO than most dynamites, which arc oxygen balanced. But all explo-
sives produce measurable amounts of CO Participates are produced as
well, but such large quantities of participate, are generated in the
shattering of the rock and earth by the explosive that the quantity of
particulates from the explosive charge cannot be distinguished. Nitrogen
oxides (both NO and NC>2) are formed, but only limited da* a are available
on these emissions. Oxygen deficient explosives are said to produce
little or no nitrogen oxides, tut there is only a small bouy of data to
confirm this. Unburned hydrocarbons also result from explosions, but in
most instances, methane is the only species that has bc?en reported.
Hydrogen sulflde, hydrogen cyanide and ammonia all have been
reported as products of explosives use. Lead is emitted from the firing
of small arms ammunition w^:h lead projectiles and/or lead primers, but
the explosive charge does not contribute to the " sad en Lssiont,.
The emissions from explosives detonation are influenced by mrny
factors such as explosive composition, product expansion, method of
priming, length of charge, and confinement. These factors are difficult
to measure and control in the field and are almost impossible to duplicate
in a laboratory test facility. With the exception of a few studies in
underground mines>, roost studies have been performed in laboratory test
chambers that differ substantially from the actual environment. Any
estimates of emissions from explosives use must be regarded as approxi-
mation that cannot be made moie precise, because explosives are not
used in a precise, reproducible manner.
To a certain extent, emissions can be altered by changing the
composition of the explosive mixture. This has been practiced for many
years to safeguard miners who must use explosives. The U. S. Burenu c"
Mines has a continuing program to study the products from explosives
-------
J.OVNAM1TI
MMMANY
HI OX EUPLOflVf
OS VI
a. Two-step explosive train
) OTNAMITI
I NOKIIIC1NIC
I tAFITr ruM
b. Ihree-step explosive train
»OV'_«MITI ~
kOOSTIR
LOW PD1MARY
I«»LOS'V[ MICH [XPLOStVl MCONDAKY mCH [XPLOSIVI
c. Four-step explosive tr»in
Figure 1^.3-1 Two-, inree-, and four-step explosive trains.
I I..T2
KMISSION KACrORS
-------
Table 11.3-1. EMISSION FACTORS FOR DETONATION OF EXPLOSIVES
(EMISSION FACTOR RATING: D)
I-,.—
Tirk povdrr?
taoke'ns
Po«oer?
Dywille.
Straight*
Dynamite.
Imnonil*
Gelatin1
ANFO* 5
TNT' 1
«,<
rn.T
r.c»wo«,IMor
7S/1S/10; pnt^sUw luxHua)
nitrate/thi noil /sulfur
nltrocell jloie luMtlMi
with other materials)
rj-rtOl M t --o<| J jc eH n»/
sodiM nltrjte/wcoc: pulp/
Cllc turn carbon4t>
ZO-tOj nitroglycerine/
•MMMitun n' !rare/Sr,31««
ni Irate/tfOOd Pulp
Pn-lftXll nlttnqlyrrrlnr
•NHonju^ nttratt tftth
' fl-fll fuc'. nil
(^hM*c?b
11 y
CiCHpOTO^I^
*„
Will arvs
rarely used
ci*>. m«thjn*. Th«y do not r*finmn\ total VOC cipKiMd a> muhine studiei were carriad out nor« than 40
>«ariagu. NA • not available.
c Greater than 6 mfl pel I SS ira.n praieclilc (0.6 kg/Mr, 1.2 Itj/lon].
d Thete factors arr denitd from theoretical calculillont. nol from experimenl'1 dfU.
-------
11.3 EXPLOSIVES DETONATION
11.3.1 General 1-5
This section deals mainly with pollutant?} resalting from the
detonation of industrial explosives and firing of small arms. Military
applications are excluded from this discussion. Emissions associated
with the manufacture of explosives are traatecl in Section 5.6,
Explosives.
An explosive is a chemical material that is capable of extremely
rapid combustion resulting in an explosion or detonation. Since an
adequate supply of o/;ygen cannot be drawn from the air, a source of
oxygen must be incorporated into the explosive mixture. Some explo-
sives, SUCT as trinitrotoluene (TNT), are single chemical species, but
most explosives are mixtures of several ingredients. "Low explosive"
and "high iixplosive" classifications are based on the velocity of
explosion, which is directly related to the type of work the explosive
can perform. There appears to be no direct relationship between the
velocity of explosions and the end products of explosive react Lens.
These and products are determined primarily by the oxygen balance of the
explosive. As in other combustion reactions, a deficiency of oxygen
favors the formation of carbon monoxide and unburned organic compounds
and producer; little, If any, nitrogen oxides. An excess of oxygen
causes more nitrogen oxides and less carbon monoxide and other unburned
organics. For ammonium nitrate and fuel oil mixtures (ANFO), :h no universally
accepted system for classifying them. The classification used in Table
11.3-1 is based on the chemical composition of the explosives, without
regard to other to other properties, uuch as rate of detonation, which
relate to the applications o+~ explosives hut not to their specific enu
products. Most explosives ^ro used in two-, three-, or four-step trains
that are shown schematically in Figure 11.3-1. Tbe simple removal oe a
tree stump might be done with a twc-step train made up of an electric
blasting cap and a stick ot dynamite. The detonation wave fro™ the
blasting cap would cause detonation of the dynamite. To make a large
hole in the earth, an ineyptnsi^e explosive such as ammonium nitrate and
fvel oil (ANFO) might be used. In this case, the detonation wave from
the blasting cap is not powerful enough to cause detonation, oO a
booster must be used in a three-- or four-step train, Ennssionu from the
blasting caps and safety f'jses used in these trains are usually small
compared to those from the main charge, because the emissions are
roughly proportional to the weight of explosive used, and the main
charge makes up most of the total weight. No factors are given for
computing emissions from blasting caps or fuses, because these have not
been measured, and b«:cau£ie the uncertainties are so great In estimating
emissions from the main and booster charges that a precise estimate of
all emissions is not practical.
2/Ho
-------
3. Melvin A. Cook, The Science of Hip.h Explosives. Reinhold Publishing
Corporation, New York, 1958.
A. R. F, Chalken, et al., Toxic Fumes from Explos.iyes: Ammonium
Nitrate Fuel Oil Mixtures, Bureau of Mines Report of Investigations
7867, U. S. Department of Interior, Washington, DC, 1974.
5. Sheridan J. Rogers, Analysis of Noncoal Mine Atmuspherc-.s; Toxic
Fume a trom Explosives, Bureau of Mines, U. S. Department oL" Interior,
Washington, DC, May 1976.
6. A. A. Juhasz, "A Reduction of Airborne Lead In Indoor Firing
Ranges by Using Modified A.-aiunition", Special) Publication 480-26,
Bureau of Standards, U. S. Department of Commerce, Washington, DC,
November 1977.
Snin-i"«
-------
APPENDIX A
.MISCELLANEOUS DATA
-------
SOME USEFUL WEIGHTS AND MEASURES
grain
gran
ounce
kilogram
pound
0.002
0.04
26.35
2.21
0.45
ounces
ounces
grams
pounds
kilograms
pound (troy)
ton (short)
ton (long)
ton (metric)
ton (shipping)
12 ounces
2000 pounds
2240 pounds
2200 pounds
40 feet3
centimeter
Inch
foot
meter
yard
mile
0.39 Inches
2.54 centimeters
30.4P centimeters
1.09 yrrds
0.91 meters
1.61 kilometers
centimeter2
inch2
foot2
meter2
yard2
mile2
0.16 Inches2
6.45 centimeters2
0.09 meters2
1.2 yards2
0.84 meters2
2.59 kilometers2
centimeter^
Inr.h3
foot3
foot3
meter3
yard3
0.061
16.39
283.17
1728
1.31
0.77
inches3
centimeters3
centimeters3
inches3
yards3
meters3
cord 128 feet3
cord 4 meters3
peck 8 quarts
bi shel (dry) 4 pecks
bushel 2150.4 Inches3
gallon (U.S.)
barrel
hogshead
township
hectare
231 inches3
31.5 gallons
? barrels
'3f. rniies2
2.5 acres
MISCELLANEOUS DATA
One cubic foot of anthracite coal wtighs about SJ pounds.
One cubic fooc f'f bltunlnous coal weighs from 47 to 50 pounds.
One con of coal ts equivalent to tvo cordt of ucod for steam purposes.
A gallon of watfr (U.S. Standard) weighs 6.J3 Ibs. and contains 231
cubic Inches.
There are 9 square feet of heating surffi.e to each sqjare foot of grate
•urface.
A cubic fo>,t of watir contains 7.5 gallons and I728 cubic Inches, and
weighs 02.5 Ibs.
Each nc&lnal horsepower of a boiler rtcuires 30 to 35 Ibs. of water per
hour.
\ horsepower le equivalent to raising 33,000 pounds one root per minute,
or 550 pounds one Coot per second.
To find the prefsure In pounds per square inch of column of water,
multiply the iieight of the ce'.^mn in feet by 0,434.
A-2
-------
PARAMETERS OF VARIOUS FUELS*
Type of Fuel
Solid Fuelu
Bltuinous Coal
Anthracite Coal
Lignite (9 351 wisture)
Wnod (9 40Z Bniature)
Bagasse (8 50 t moisture)
Bark (f 503, noiature)
Coke, Byproduct
Li quid j'uelr
Residual Oil
L-ietlllate Oil
Diesel
Gasoline
Kerosene
Liquid Petroleun Gas
Gaseous Fuels
Natural Gas
Coke Oven Gas
Blast Furnace Gas
Hettlrg
teal
7,2CO/itg
6,810/kg
3,990/kg
2,880/kg
2,220/kfc
2. 492 /kg
7 ,380/kg
9,98 x 106/m3
9.30 k I06/ffl3
9.12 x 106/ni3
8.62 x 106/n3
8.32 x 10* /n3
6.25 x I06/m3
9,341/ta3
5,249/nm3
D Qf| / *>ih J
o™y / us
Value
BTU
13,OOC/lb
12.300/lb
7,200/lb
5.200/lb
4,000/lb
4,WO/lb
13,300/11;
l:0,OOO /gal
140,000/gal
137, 000 /gal
130,000/gal
135,000/gal
94,000/gal
1,050'SCF
$9Q/$Ct
100/SCF
Sulfur
Z (by weight)
0.6-5.4
0.5-1.0
0.7
N
N
K
0,5-1.0
0,5-4.0
U.Z-l.O
0.4
0.03-0.04
0.02-0.05
N
N
0.5-2.0
M
Aah
% (by wcighr)
4-20
7.0-16.0
6.2
1-3
1-2
1-3 *
O.S-S.O
0.05-0.1
N
N
N
N
N
N
N
N
«N - negligible.
bAah content nay be considerably higher when sand, dirt, etc. are pre0e.it.
-------
THERMAL EQUIVALENTS FOR VARIOUS FUELS
Type of fuel
Btu (gross)
kcal
Solid fuels
P.i'uminous coal
Anthracite coal
Lignite
Wood
Liquid fuels
Residual fuel oil
Distillate fuel oil
Gaseous fuels
Natural gas
Liquefied petroleum gas
Butane
Propane
(21 0 to 28.0) x
25.3 x
16.0 x
21. Ox ID6 /cord
6.3 x 108/bbl
5.9 x 106/bbl
1.050/ft''
97,400/gil
90.500/fial
(5.8 10 7.3} x
7.03 x 10G/MT
4.45 x
1.47 x
10 x If^/liter
9.3Sx
9,350/m3
6.480/liter
6.030/liter
WEIGHTS OF SELECTED
SUBSTANCES
Type of substance j ItVgal
V
Asphalt
Butane, liquid at 60" f
Crude oil
Distillate oil
Gasoline
Propane, liquid at 60° F
Residual oil
Water
a 57
4.S-J
7.08
7.05
6.17
4.21
78-
84
g/liter
1030
579
850
845
739
S07
944
1000
A-4
-------
DENSITIES Of SELECTED SUBSTANCES
Substance
Fuel*
Crude Oil
Residual Oil
Distillate Oil
Gasoline
Natural Gas
Butane
Propane
Wood (Air dried)
Elm
Fir, Douglas
Fir, Balaam
Hemlock
Hickory
Maple , Sugar
Maple, White
Oak, Red
Oak, White
Pine, Southern
Agricultural Products
Corn
Mllo
Oats
Barloy
Wheat
Cotton
Mineral Products
Brick
C
-------
CONVERSION FACTORS
The table of conversion factors on the following pages contains factors
for converting English, to metric units and metric to Eng.llsh units js well as
factors to manipulate units within the same system. The factors are arranged
alphabetically by unit: within the following property groups.
o Area
o Density
o Energy
i> Force
o Length
o Mass
o Pressure
o Velocity
o Volume
o Volumetric Rate
To convert a number from on>? unit to another:
1) Locate the unit in which the mimher is currently expressed in the
left har.d column of the tahle,
2) Find the desired unit in the center column, and
3) Multiply the number by thy corresponding conversion factor
in tlu«. right hand column.
A-7
Preceding page blank
-------
CONVERSION FACTORSa
To concert from to multiply by
Area
Acres .................. Sq feet .................... 4.35* x
Acres .................. Sq kilometers .............. 4.0469 x 10"3
Acres .................. Sq meters...- ......... . ..... 4.0469 x 103
Acres .................. Sq miles(statote) .......... 1.5625 x 1C"3
Acres.... L ............ . Sq yards ..... . ............. 4.84 x 1C3
Sq feet ................ Acres ...................... 2.2957 x 10"^
Sq feet ................ 3c cm ...................... 929.03
Sq feat. ........... ..... Sq inches .................. 144.0
Sq feet ................ Sq ranters .................. 0.092903
Sq feet ........ . ....... Sq miles ................... 3,587x10-3
Sq feet .......... . ..... Sq yards ................... O.lllil;
Sq inches .............. Sq feet .................... 6.3^44 x 1CT-*
Sq inches ....... . ...... Sq meters ............. ..... 6.4S16 x 10"^
Sq inches .......... .... Sq mm ...................... 645.1^
Sq kilometers .......... Acres ...................... 247.1
Sq kilometers .......... Sq feet ......... . ..... .... 1.0764 x 10'
Sq kilometers .......... Sq meters .................. 1.0 x If)6
Sq kilometers .......... Sq miles ................... 0.386102
Sq kilometers .......... Sq yards ............. ..... 1.196 x )06
Sq meters .............. Sq cm ...................... 1.0 x 10^
Sq meters .............. Sq fert .................... 10.764
Sq meters .............. Sq inches .................. 1.55 x 103
Sq rasters .............. Sq kilometers..... ......... 1.0 x 1 0~6
Sq meters .............. Sq miles ................... 3.861 x 10~7
Sq meters .............. £q mm ..... . ................ l.OxlO6
Sq meters .............. Sq yards ................... 1.196
Sq miles ............... Acres .............. , ....... 640.0
Sq miles ............... Sq Eeet .................... 1.7878 x 107
Sq miles ............... Sq kilometers .......... .... 2.590
Sq miles ............... Sq meters ...... , ........... 2,59 x 10&
Sq miles? ............... Sq yards ................... 3.0976 x iO6.
Sq yards ............... Acres ...................... 2.3661 x 10~4
Sq yards ............... Sq cm., .................... 8.3613 •'. io3
Sq yards ........ . ...... Sq fr .................... , . 9.0
Sq yards ............... Sq Inches .................. 1.296 x 10^
Sq yards ............... Sq meters .................. 0.33M3
Sq yards.. ............. Sq miles ................... 3.22f3 x 10~;
aWhere appropriate Lhe conversion faf;ora aopearlng IP this tsble
have been rounded to four to six significant, i igures i'oi- ease in
use. The accuracy of these numbers is considered suitable for use
with emissions data; If a raoire accurate number Is esquired, tables
containing exact factors should be consulted.
A-b
-------
CONVERSION FACTORS Contd.
To convert from
Density
to
multiply by
Dynes/cu cm
Gralns/cu foot
Crame/cu cm
Grams/cu cm
Grams/cu cm
u cm. • . . ........
Grams/cu cm ............
Grams/cu cm ............
Grams/cu cm .......... . .
Grams/cu cm. . ..........
Grams/cu cm. ... ........
Grams/cu mecer .........
Grams/11 ter .......... . <
Kllograms/cu meter .....
Kllograms/cu meter .....
Kllograms/cu meter .....
Pounds /cu foot..i. .....
Pounds/cu foot .........
Pounds/cu inch .........
Pounds/cu inch .........
Pounds/cu inch .........
Pounds/gal (U.S., liq).
Pounds/gal (U.S., liq).
Energy
Graras/cu cm 1.0197 x 10~3
Grams/cu meter 2.28835
Dynes/cu era 980.665
Grains/mi 111 liter 15.433
Grams/rallliliter 1.0
Pounds/cu Inch 1.162
Pounds/c foot 62.428
Pounds/cu inch 0.036127
Pounds/gal (Brit.) 10.022
Pounds/gal(U.S. , dr •) 9.7111
Pounds/gaKU.S., Iti.) 8.3454
Gralns/cu foot 0.4370
Pounds/gal (U.S.) 8.345 x 10~3
Crams/cu cm 0.001
Pounds/cu ft 0.0624
Pounds/cu in 2.613 x 10
Grams/cu cm 0.016018
Kg/cu meter 16.018
Grams/cu cm 27.68
Grams /liter , 27.681
Kg/cu meter..... 2.768 x 1
Grams/cu cm 0.1198
Pounds/cu ft 7.4805
*5
Btu Cal. ,£m (1ST.) 251.83
Btu Ergs 1.0H35 x JO10
Btu Foot-pounds -. 777.65
Btu Hp-hours 3.9275 x 10~4
Btu.. .'oulesdnt. ) 1054.2
Btu Kg-meters 107.51
Btu , Kw-hours(Int.) 2.9283x10"*
Btu/hr Cal.,k£/hr 0.252
Btu/hr ; Ergs/iec 2.929 x 106
Btu/hr Foot-pounds/hr 777.65
B«-u/hr Horsepower (raechanic.il).... 3.9275 x 1C"4
Btu/hr Horsepower (boiler) 2.9856 x 10~5
Btu/hr Horsepower (electric) 3.926 x 10~4
Btu/hr Horsepower (metric) 3.982 x 10~4
Btu/hr Kilowatts 2.929 x 10"4
Btu/lb Foot-poands/ib 777.65
Btu/lb Hp-hr/lb 3.927S x IT4"
Btu/lb Joules/gram 2.3244
Calories,k£(mcan) Btu(lST. ) 3.9714
Calories,kg_( mean) Ergs 4.190 x 1010
A-9
-------
CONVERSION FACTORS Contd.
To convert from
to
multiply by
Calories,k^Cmean) Foot-pounds 3.0904 x
Calories,k£(mean) Hp-hours 1,561 x 10~3
Calories.k^(me?n) Joules 4. 190 x 103
Calories,lc£(iv.ean). ..... Kg--rnetero 427.26
Calories,jt£(mean) Kw-ho-jrs( Int.) 1.1637 x 10~3
Ergs .Jtu 9.4845 x 1CT11
Ergs Foot -ponndals ,. 2.373 x 10~^
Srgs Foot-pounds 7.3756 x 10~8
Ergs Joules (Int.) 9.99835 x 1CT8
Krgs Kw-hours 2.7778 x 10~14
Ergs Kg-raetsrs 1.0197 x 1CT8
Foot-pounds Btu(ISf.) 1.2851 x 10~3
Foot-pounds Cal. ,k£ (1ST , ) 3.2384xlO~4
Foot-pounds Ergs 1.3558 x 107
Foot-pounds.. Foot-pcundals. 32 > 174
F^ot-pounds Hp-hoars 5.0505 x 10~7
Foot-pounds Joules 1. 3558
Foot-pounds K^-meters 0.138255
Foot-pounds Kw-hours(Int. ) 3.76554 x 10"?
Foot-pounds Newton-meters..... 1,3558
Foot-pounds/hr Btu/:air: ,., 2.U32 x 10"5
Foot-pounds/hr Tirgs/mln 2.2597 x 105
Foot-pounds/hr. Horsepower (mechanical).... 5.0505 x 10"'
Foot-pounds/hr Horsepower (metric^ 5.121 x 10"'
^oot-pounds/hr Kilowatts 3.766xlO"7
Horsepower (mechanical) Btu(maan)/hr 2.3425 X llP
Horsepower (mechanical) Ergs/sec 7.457 x 10"
Horsepower (mechanical) Foot-pounds/hr 1.980 x 10"
Horsepower (mechanical) Horsooower (boiler) 0.07602
Horsepower (mechanical) Horsepower (electric). 0.9996
Horsepower (mechanical) Horsepower (metric)........ 1.0139
Horsepower (mechanical) Joules/sec 745.70
Horsepower (mechanical) Kilowatts(lnt.) 0.74558
Horsepower (boiler).... Btu(mean)/hr 3.3446 x 10^
Horsepower (boiler).... Ergs/sec 9.8095 x 1010
Horsepower (boiler).... Foot-pounds/min 4.341 x 10^
Horsepower (boiler;.... Horsepower (mechanical)..., 13.155
Horsepower (boiler).... Horsepower (electric) 13.15
Horsepower (boiler).... Horsepower (metric) 13.337
"orsepower (boiler) Joules/sec 9.8095 x 10^
Horsepower (boiler).... Kilowatts 9.8095
Hor-.jpower (electric).. Btu(mean)/hr 2.5435 x 103
Horsepower (electric).. r,al.,kj>/hr 641.87
Horsepower (electric).. Ergs/sec 7.46 x
Horsepower (electric).. Foot-pounds/min 3.3013 x
Kofhtpou-cr (?l«^trlc).. Horsepower (boiler)..- 0.0760b
Horsepower (elert ric). . Horsepower (meLrl,-) - - • 1.0143
Horsepower (electric).. Joules'sac 746.0
A-10
-------
CONVERSION FACTORS Contd.
To convert from
Horsepower (electric). .
Horsepower (metric)....
horsepower (metric)....
Horsepower (metric)....
Hor«^pover (metric)....
Horsepower (metric)....
Horsepower (metric)....
Horsepower (metric)....
Horsepower (metric)....
Horsepower-hours ...... <
Horaepower-houi'-. ......
Horsepower-hour a .......
Horsepower-hours .......
Horsepower-hours .......
Joules
Joules
Joules
Joules
Joules
Joules
Joules
Joules
)
)
)
)
)
)/sec
)/sec.
)/sec
(Int.
(Int.
(Int.
(Int.
(Int.
(Int.
(Int.
(lnt.
Kilogram-meters ..... ...
K.ilogram-niei.3s.'s. . ......
Kilogram-meters ........
Kilogram-meters .......
Kilogram-meters ........
Kilogram-meters, ...... .
Kilogram-meters ........
Ki] cgram-metera ........
Kilogram-raeters/sec. . . .
Kilowatts (Int.
Kilowatts (Int.
Kilowatts (Int.
Kilowatts (Int.
Kilowatts (Int.
Kilowatts (Int.
Kilowar.ts (Int.
Kilowatts (Int.
Kilowatts (Int.
Kilowatts (Int.
Kilowatts (Int,
Kilowatt-houra
Kilowatt-hours
Kilowi.tt-hours
Kilowatt-hours
Kilowj tt-hours
(Tnt.)..
(Int.)..
(Int.)..
(Inr.).,
(Int.)..
to
Kilowatts
Btu(mean)/hr
Ergs/sec
Foot-pounds/min.
Horsepower (mechanical)....
Horsepower(boiler)
Horsepower (electric)
Kg-meters/sec
Kilrwatta
Btu(mean).
Foot-pounds................
Joules •
Kg-meters
Kw-hours.
Btu (1ST.)
Ergs
Foot-poundals
Foot-pounds
Kw-hours
Btu(ntean)/min
Cal. ,k£/iii-,i
Horsepower.
Btu (mean)
Cal. ,kg_ 'mean)
Ergs
Foot-poundals
Foot-pounds
Hp-hours
Joules (Int.)
Yv-hours i........
Watts
Btu (IST.)/hr
Cal,k£ (!ST.)/hr
ErgsTsec
Foot-poundals/mln
Foot-pounds/rain
Horsepower (mechanical)....
Horsepower (boiler)
Horsepower (electric)......
Horsepower (metric)
Joules (Int.)/hr
Kg-meters/hr
Btu (mean) •
F->ot-pounds
Hp-hours
Joules (Int.).i
Kg-meturs
multiply by
0.746
2.5077 x 1C3
7.355 x
3.255 x
0.98632
0.07498
0.9859
75.0
0.7355
2.5425 x IO3
1.98 x IO6
2.6845 x IO6
2.73745 x IO5
0.7457
3.4799 x IO-4
1.0002 x IO7
12.734
0.73768
2.778 x 10~7
0.05633
0.01434
1.341 x 10~3
9.2878 x 10~3
2.3405 x 10~3
9.80665
232.715
7.233
3.653 x
9.805
2.724 x
x 10'
10
-6
10
,-6
10
9.80665
3.413 x 103
860.0
1.0002 x 10
1.424 x iO6
4.A261 x IO4
1.341
0.10196
1.3407
1.3599
3.6 x IO6
3.6716 x IO5
3.41 x IO3
2.6557 x IO6
1.341
3.6 x IO6
3.671b x IO5
A-ll
-------
CONVERSION FACTORS Contd,
To convert from to multiply by
Newton-meters Gram-era... 1.01972 x K
Newton-meters Kg-raeters 0.101972
Newton-metec-*. Pound-feet 0.73756
Force
1.0 x 10"5
7.233 x 10~s
2.248 x 10~6
1.0 x 10~5
C. 22481
,, 1.333 x 10*
0.1383
0.03108
i.448 x 10-
4.448
32,174
Centimeters 30.48
Incher , 12
Kilometers , 3.048 x 10-
Meters 0.3046
Feet Miles (statute) 1.894 x 10~4
Inches Centimeters 2.540
Inches Feet 0.08333
Inches Kilometers 2.54 x H~J~5
Inches Meters 0-0254
Kilometers," Feet 3.2808 x 103
Kilometers Meters 1000
Kilometers Miles (statute) 0.62137
Kilometers Yards 1.0936 x 10J
Meters Feet 3.2808
Meters .. Inches 39 370
Micrometers... Angstrom units 1.0 x ! 0/4
Micrometers Centimeters 1.0 x 10~3
Micrometers Feet 3.2808 x 10~6
Micrometers Inches ,,. 3.9370 x 10"5
Micrometers Meters 1,0 x 10~6
Micrometers Millimeters 0.001
Micrometers, Nanometers 1000
Miles (statute) Feet 5280
Miles (statute) Kiloneters 1.6093
Miles (statute) Meters 1.609.1 x 103
Miles (statute) Y-rds 1760
Millimeters Angstrom units 1.0 x 1C7
Millimeters. Centimeters 0.1
Millimeters...., Inches. 0.03937
Millimeters Meters 0.001
A-12
-------
CONVERSION FACTORS ContJ.
To convert from
to
multiply by
Mil 11 neter^ ••**•»•
Yards
Mils
1000
39.37
10
1.0 y 10~?
3.937 x 10"
O.JO I
1.0 x i o~'J
0.9144
8
Mass
Grains
Grains
Grains
Grains
Grains...
•Trams ........ ,
Crams..
Grams
Grams
Grams
Grams .........
Kilograms
Kilograms
Kilogram;
Kilograms
Kilograms
Kilograms
Kilograms
Megagrams;
Milligrams
Milligrams
Mllli^ams
Milligrams
Milligrams
Milligrams
Ounces (apoth.
Ounces (apoth.
Ounces (apoth.
Ounces (avdp
Ounces (avdp
Ounces (avdp
Ounces (avdp
""incee (avdp
Pounds (avdp
Pounds (avdp
oc troy)
or troy)
or trov)
Crams .......... . ...........
Milligrams .................
Pounds (apoth. or troy)....
Pounds (avdp. ) .............
Tons (metric) ........... ...
Dynes ......................
Grains .....................
Kilograms ..................
Ml c cog rams .................
Pounds (avdp.) .............
Tons, metric (megagrams). . .
Grains .....................
Poundals ...................
Pounds (apoth. or troy) .....
Pounds (avdp.) .............
Tons (lon^) ................
Tons (metric) .......... ....
Tons (short) ...............
Tons (metric) ..............
Grains .....................
Gr^ms ......................
Ounces (apoth. or troy)....
Ounces (avdp.) .............
Pounds (apoth. or troy).. .
Pounds (avtip.) ...... > ......
Grains .....................
Grams. .....................
Ounces (advp.) .............
Grains .................. ...
Grams .......... . ...........
Ounces (apoth. or troy)....
"ounds (apoth. or troy)....
Pounds (avdp.) .............
Poundals ...................
Pon.r.drf (apoch. or troy)....
0.064799
64.799
1.7J61 x 10"''
1.4286 x 10~'4
6.4799 x !0"8
930.67
15.432
0.001
10
1 x
2.205 x
1 x 10~°
1.54J2 x 10^
70.932
2.679
2.2046
9.842xlO~4
0.001
1.1023 x 10~3
1.0
0.01543
1.0 x 10~-
3.215 x 10~5
3. 527 x 1 0~5
2.679 x 10~&
2.2046 x K~6
480
31.103
i.097
437.5
28.350
0.9115
0,075^55
0.0625
J2.174
1.2153
A-13
-------
CONVERSION FACTORS Contd.
To convert ftom
to
multiply by
Pounds (avdp.) Tons (long)
Pounds (rivdp-) Tons (metric)
Pounds (avdp.) Tons (short) ,.. ...
Pounds (avJp.) Grains.....
Pounds (avdp.).... Grams
Pounds (avdp.) Ounces (apoth. or trey)....
Pounds (avdp.) Ounces (avdy.,v...
Tons (long) Kilograms
Tony (long) founds (apoth. or troy)....
Tons (long). Pounds (avdp.)
Tons (long) Tons (metric)
Tons (Icing), Tons (short)
Tons (metric). Grams
Tons (metric). . Megagrams
Tons (metric) Pounds (apoth. or troy)....
Tons (metric) Pounds (avdp.)
Tons (metric) Tons (Long)
Tins (metric) Tons (short)
Tons (short) Kilograms
Tons (short) Pounds (apoth. or troy)....
Tons (short) Pounds (avdp.)..
Tons (short) .. ^cns (long)
Tons (short) Tons (metric)
Pressure
4.4643
4.5J59
5.0 x
7000
43.1. 59
14..S83
16
x 10-4
x 10~4
io~4
l.Glh x 10*
2.722 x 103
2.240 x 103
1.016
1.12
1.0 x
1.0
2.6V92
2.2046
0.984?
1.1023
907.18
2.4301
2000
0.8929
0.907?.
106
x 10-'
x 10^
x 103
Atmospheres
Atmospheres
Atraos phe re s
Atmospheres
Atmospheres
A tmo B phe res
Inches of Hg
Inches
Inches
Inches
Inches
Inches
Inches
Inches
Tn-heG
of
of
of
of
of
Hg
Hg
'Ig
H-,0
H^O
H20
(60°F)....
(60°F)....
(60°FU...
(COT)....
(4*C)....
(4"C)....
(4°C) ----
of l\2^ (4°C) _____
n* H^O (4°C)....
Kilograms /sq cm. . ......
Kilograms/sq era ........
Kilograms/sq cm ........
Kilograms/aq ctj ........
Kilograms/ jq cm. .......
Millimeters of Hg (C°C)
MtUln.«c
-------
CONVERSION FACTORS Contd.
To convert from to multiply by
Millimeters ->f Hg (0°C) Pounds/sq Inch 0.019337
Pounds/sq Inch.. Atmospheres 0.06&05
Pounds/aq inch Cm of Hg (O'C) 5.1715
Pounds/sq inch Cm of H-;0 (4°C).... 70.309
Pounds/sq inch Inof Hg(32°F) 2,030
-'oiinds/sq inch In of H20 (39.2F) 27.681
l'i.'>nds/sq inch Kg/sq cm 0.07011
Pounds/sq inch Mm of Hg (0°C) 51.71:>
Velocity
Centimeters/sec Fect/miu 1.91.85
Centimeters/sec Feel/sac-, 0.032?
Centimeters/sec Kllomfet&rs/hr 0.036
Centimeters/sec Meters/rain 0.6
Centimeters/sec Hlles/hr 0.02237
Feet/minute Cm/sec 0.508
Feet/minute Klloraeters/hr 0.01829
Feet/minute Metcrs/min 0.3048
Feet/minute Meters/sec 5.08 x 10~3
Feet/minute Miles/hr 0.01l3j
Feet/sec Cm/sec 30.48
Feet/sec KUometers/hr 1.0973
Feet/sec Meters/min 18.288
Feet/sec Milea/hr 0.68)8
Kiloraeters/hr Cm/sec 27.778
Kiloiueters/hr Feet/hr 3.2808 x HI3
Kilometers/hr Feet/min 54.681
Kilometers/hr Meters/sec 0.27778
K.ilometerp/hr Milos (scatute)/hr 0.62137
Meters/min C'Wsec 1.6667
Meters/min Keet/min 3.2808
Meters/min fer.t/ser 0.05468
Meters/min Kilom?Lers/\cr 0.06
Miles/hr Cm/sec 44.704
Miles/br Fcet/hr S.180
Miles/hr Fecr/min 88
Milfes/hr Keet/sec. 1.4667
Ml les/hr Ki lometers/hr 1.6093
Miles/hi Meters/r.i.'-i ?.6.822
Volume
Barrels (pet>-oleiim,US). O feet 5.6146
Barrels (petroleum,US ). Gallons (US) 42
Bnrrels (petroleum,US). Liters 158.98
Barrels (US, liq.) Cu feet 4.2109
Barrels (US, Hq.) ('n Inches 7.2765 x 10
A-15
-------
CONVERSION FACTORS Contd.
To coiverc from
barrels (US, liq.).
Barrels (US, liq.).
Barrels (US, liq.).
cent!meters.,
cent imeters..
centimeters..
centImeters..
cent Imeters,.
centI meters..
feet.
feet.
feet.
feet.
inches.
Inches.
Inches.
Inches.
Inches.
Inches.
Inches.
meters.
meters.
meters.
meters.
meters.
meters.
meters.
yards,
to
Cu meters ..................
Gallons (US, llq.) .........
Liters ................. , . . .
Cu feec... .............. ...
Cu Inches ...... ...... ......
Cu mete is ............... ,,.
Cu yards ...................
Gallons (US, Uq.) ..... .....
Quarts (US, llq.) ..........
Cu centimeters .............
Cu meter?; ...... . ...........
Gallons (ITS, liq.) .........
Liters .....................
Cu cm ......................
Cu feet ....................
Cu meters ..................
Cu yards ...................
Gallons (US, llq.) .........
Liters .....................
Quarts (US, llq.) ..........
Barrels (US, llq) ..........
Cu en ......................
Cu feet .................. , „
Cu Inches ..................
Cu yards ...................
Gallons (US, tin.) ........
LUirs ................ .....
Bushals (Brit.) ............
Bushels (US) ...............
'Ju cm ......................
Cu feet ....................
Cu Irenes ..................
Cu it.-ters ..................
Gallons ....................
multiply by
0.1192
31.5
119.24
3.5315 x
0.06102
1.0 >: 10
308
10
1
2.6Ai! v. 10'4
1.0567 x 1(T3
2.8317 x 10*
0.02S317
7.4605
28.317
16.387
5.787 x 10-4
1.6387 x 10~5
2.1433 x JO"5
4.329 x 10-3
0.01639
0.01732
8.336A
1.0 x 106
35.315
6.1024 x
1.308
264.17
1000
21.023
21.696
7.6455 .«
27
4.6656 x
105
10
Gal Ions ....... ,.
Liters ............. .
Qua rts
Qua rts
Quarts ..........
barrels (US, liq.)
Barrels ( petroleum, LS
Rush,?. Is (US)
13
J7
97
.5!)
71
.22
.90
Cu
Cu
fu
Cu
reft
Inches
IIP "r- r
-------
CONVERSION FACTORS Contd.
To convert from
Gallons (US, liq.)
Gallons (US, liq.)
Gallons (US, liq.)
Gallons (US, liq.)
Gallons (US, liq,)
Liters ,
Liters
Liters
Liters
Liters
Liters
Volumetric Rate
to
Gftlions (wine) -...
i jLv*? rs •••**•••••••••••»•»»!.
Ounces (US, fluid)
Pints 'US, liq.)
Quarts (US, liq.)
Ct centimeters
Cu feet
Cu inches.
Cu naters
Gallons (iJS, liq.)
Ounces (US, fluid)
Cu ft/min
Cu ft/mln
Cu ft/min
Cu ft/min
Cu meters/min, ..
Cu raeters/min...
Gallons (US)/hr.
Gallons (US)/hr.
Gallons (US)/hr.
Gallona (US)/hr.
Liters/min
Liters/rain.....•
Cu cm/aec
Cu ft/hr
Gal (US)/min.
Gal ;'US)/min .......
Liters/min .........
Cu ft/hr ...........
Cu meters/rain ......
Cu yd/ rain ...... . . . .
Liters/hr ..........
Cu ft/rain ..........
Gal (US, llq.)/min.
multiply by
1.0
?.7354
128.0
3.0
4.C
1000
0.035315
61.024
0.001
O..i642
33.814
471.95
60.0
7.4805
0.47193
264.17
999.97
0.13268
6.309 x 10~5
8.2519 x 10-5
3.7854
0.0353
0.2642
A-17
-------
CONVERSION FACTORS FOR COMMON AIR POLLUTION MEASUREMENTS
AIRBORNE PAKTICULATE MATTER
To convert from
Milllprans/'Ju a
Grans/cu ft
Grama/cu m
M-crograae/cu >n
Mlcrograns/eu ft
Pounds/1000 cu fr
To 1
Grams/cu ft
Grams/cu m
Mlcrograma/cu ra
Mlcrograma/cu ft
Pounds/1000 cu ft
Mliltgrams/o. a>
Grama/cu m
ilcrograna/cu ro
!llcrograms/cu It
l'ounds/1000 cu ft
'''llltgrams/cu m
Grams/cu ft
i-llcrograms/cu m
Mlcrograma/cu ft
Pounds/1000 cu ft
Mllligrams/cu m
Grama/cu ft
Grams/cu a
Mlcrograos/cu ft
Pounda/1000 cu ft
Mllllgrans/cu m
Grams/cu ft
Grams/cu m
Mlcrograina/cu m
Pounds/1000 cu ft
Milllgrams/cu ra
Grans/ cu ft
Micrograms/cu o
Graos/cu m
Mlcrograms/cu ft
Multiply by
283.2 x ID'6
0.001
I 000.0
28.32
62.43 x 10-6
35.3145 x 10^
35.314
35.314 x 106
I .0 x 106
2.2046
1000.0
0.02832
1.0 x 106
28.317 x 103
0.06243
0.001
28.317 x 10-9
1.0 x 10"6
0.02832
62.43 x 10-9
35.314 x 10-3
1.0 x 10-6
35.314 x 10-6
35.314
2.2046 x 10-6
16.018 x 10*
0.35314
16,018 x 10-
16.0L8
353.14 x 103
SAMPLING PRKSSUTIE
To convert fron
To
Multiply by
Milllnete-s of mercury
Inches of merrury
(O'C)
lnchc« of water (60°F)
Indict of watot (60°F)
Inches of watei.- (60JF)
Millimeters of mercury j
(O'Y.)
Ir.ches of rcercury (0°C)'
0.5356
13.609
1.8663
73.48 x 10-3
A-ia
-------
CONVERSION FACTOR'* FOH. COMMON AIR POLLUTION MEASUREMENTS
ATMOSPHERIC GASES
To convert from
Mllligr;uns/eu m
Mlccograuis/cu IT
MlcrogiMiDs/ liter
Ppm by voluve (20°C)
Ppm by weight
PoundB/CU ft
To
Micrograras/11ter
P|«n by weight
round s/L'u ft
Ml' Hgrams/ci. ra
h. crcgrams/cu ra
Mlcrograras/llter
Ppm by volune (?C°C)
Po-inda/tu ft
Ml 11 Igirans/cu n
Ml crograms/cu m
M1 crograms/11ter
Ppm by /oliine C20°C)
Pptn by weight
MlcrograiBB/cu T
Mi crogiams/liter
Ppn by voi joe (20*c)
P;ru by weight
Pound s/cu ft
Ml 11 Igranis/ ru m
Mlcrogrjiis/ilter
Ppm by vol'jJie (20°C')
Ppn by weight
Pounds/cu ft
Ml I llgrams/cu to
Mlcrograms/cu m
Ppn by volume (208C)
Ppoi by weight
PCunds/cu it
Mill Igrams/cu m
Multiply oy
i000.0
1.0
2t* .04
M
0.8347
62.43 x 10-9
0.001
0.001
0.02404
M
834." x 10-6
62.43 x 1C 'I?
1.0
1000.0
24.04
M
0.8347
62.43 \
M
24.04
M
0.02404
M
24.04
M
28.8"
M
385.1 x 100
1.198
7.a .a
M
7.48 x 10-6
16.018 x 10?
16.016 x 106
385.1 x 1C.6
M
133.7 x 103
M = Molecular weight r>f f,ds,
A-19
-------
CONVERSION FACTORS FOR COMMON AIR POLLUTION MEASUREMENTS
VELOCITY
To convert from
Meters/sec
Kilometers/ hr
Feet/pec
Mlles/hr
To
Kilometers/hr
Feet/sec
M!les/hr
Meters/3tlc
Feet/sec
Mlles/hr
ite tters/sec.
Kilometevs/hr
Milee/hr
Meters/sec
Kilometera/hr
Feet/sec
Multiply by
3.6
3.281
2.237
0.2778
0.9113
0.6214
0.3048
1.09728
0.6818
0.4470
1.6093
1.4667
ATMOSPHERIC PRESSURE
To convert from
Atmospheres
Millimeters of mercury
Inches of mercury
Millibars
To
Millimeters of mercury
Inches of mercury
Millibars
Atmospheres
Inches of mercury
Millibars
Atmospheres
Mil] tmeters ol mercury
Millibars
Atmosphere;
Millimeters of mercury
Inches of mercury
Multiply by
760.0
29.92
1013.2
1.316 x 10-3
39.37 x 10-3
1.333
0.03333
25-4035
33.35
0.00987
0.75
0.30
VOLUME KHTSSIONS
To convert fror\
Cubic m/rain
To Multiply by
Cubic ft/iln
Cubic ft/min Cubic ro/mln
35-314
0.0283
A-20
-------
»OTU» f.W RSION FACTORS
1 H-g.vatt - -n.5 x 10*> »Tl7hr
(S to 14 it 10* HTU/ht)
1 Megawatt " 8 > 103 Ib iccan/hr
(6 to 11 > 10.3 Ib .teaa/hr!
1 8HP
- 34 .5 Ib «te»i-/hr
1 IMP - H5 i 10^ BTU/hr
(4C to SO x 10* BVU/l-.r)
1 It itean/hr • 1.4 x 1C1 BTi;/hr
(1 .2 :o 1.7 ., 10' »TU/rir)
NOTES: Ti the r>- I.I: I onaM ps ,
Megawatt Ifi the net electric pc-*er piouuetlon of d atea
eU-ctrlc pcw«r plant.
BHP la bo:10-4
— _l
"".SUSxKr"
L •••
,..,
— ... - ^
barrcU
(U. S.)
1, 37429.10-*
8.387,10'*
r • • - '
b.187jlC-3
U-
2. 8xiO-4
0.031746
0.23743
cu. ft.
b. 78704, 10-4
3.5316»10-5
T.035-16
1.0443,10*3
0.13368
4.2109
u. S. gallon of uater at 16.7"C (62T) weigh" ' 7 SO Kg. or 8.337 pounJt (avoir.)
MASS
Gram
m-'tramB
Ounce! CBvoir.)...
Pounds (evolr.)*..
i'oni (U. S . )
Mllli grans
gUrfl
1000
28.350
-.13. 59
O.C(i4?0
9.072x:;>''
C.C01
| ounces
kilograms 1 (avoir.)
0.001 !3,5:7>:10-2
! 35.274
0.026350 :
0.45359 lfa.0
6.480llO-5 2.286X10-3
'
907.19 3.200»1C*
IxlO"6 ..1.527x10-5
pounds
(avoir.)
2.205x10-'
2.2046
0.0625
I .i29«10"4
200t
2-20ixlO-6
1
4unti
(u. s.)
15.432 I 1.102»1C-^
15432 ! !.102:'C-'
437.5 3.125>1C-'
. 7coo s.Oiii';-4
7.u:.«;o-8
1.4xlD7
j.. 115412 l.',L-2»iO-9
ail llgraaa
,_ UOO
lilO6
2.8350x10'
4.5359xi05
*•
f>4.7<»-*
9.071Bxl()H
[..................
of 27.692 ;ubl.- Inches u»ttr
In air at 4.r'C. 7SO nm im»i.ury iir
-------
Win:, AND ENERGY
I G'ram Ca Inrli*s
; t aea n)
B- c'l.
: Kt 'o^rjia Ce lo ' i" t
0 ••')! <..1«(,«10'
t
. ,«i .inn Klo"'
_(
|2.Ji89.1tl-n
JCK.iCfl
I: .IBf,
41Bd
re. it>.
a i j . i i > i o i
3.9bflUn'0 3.0876
j_^
3."r.l>0 I MM7.4
jjc.ules • C..'HBS l2.3889ilD"'' IjlU7
i P.1-' (•"•" •>. --"i *j';*.* .
IFMVC Pn,;nd.i j D.JZja1* ]_ 3^:3119.JO'4^! - J»B2_»_1C' I 1.3»8 j I.i«5**lu 3
0.73756
.-. »n»r.« \.-Atm '• _ IIP _Hoi>rn_ I lj[. poji«la_;ol HA J_ I*
3.ft2fca^ O.C«i3iI I t .' b^lx'. II "'' 9*. i^i ! I -l<*28j(10-fc ll -I62BK10~^
42t ^ I 41 .1!' I 1 .'.'i'10-:)i 1 .1621
.. i . ,. ! , ; , . . I
3.2M9B i.05«4»l01;;l lt,'.'.8 ..) 777.»8
i 1 . I 7 I JL
J_9.8t89«lC j* ^J^iMx'.O ' 2";.iK; ', 2.777B1ID"' j 2.777BMilt"^
..' 2.3427
24-ZOt
iHuisppuwcr H r-* . 8.4I1O«1C'
?.!42
O.Oi.-' O.O31QB1 I 4.297ZilO"3| 4 .1 iS^jilO"11 ! 1.5697.10"^ [ 1 .1705}*'.0-tl]j .UOl'inlO- >
KU-."iit. Ho.m . ..i 8.t.OO;»lG* I 860^^1 !3.6DO(J»10!^ U.tOOO»:0* 1*13.0 | r.^SSZiiO' I ] 670VilC"bl T-SUSjlO* I 1.3*40 . B.ytJOulo' I I 1UOQ
"~t 1~^lo^ri~7"lfl7rje~.l7^n ]
|KH_
|Uat» Ho-'I-i
1*13.0 I 2.6S52M1U' I ]
Bi,n.C. , O.BtOOl [s.iOCC.lO10! JJ6C10 i _)-4130 j __2655.J | 367.
-------
POUEE
Walls
Klinvatts
FCM> t pu urxJ a JK r
second . .
trga per second . -
HTL'* r«;r nlnute - -
Odo C«j:u IvvttN s
Ki logr^ri rrlur ies
pc r nl nutt .....
Horse powpr (U . 5> . )
I »
Joulen p«r sicLond
wacra
100C
..,io-7
17.5BO
(- '-
9 8U67xlO '5
u9./6/
>4b.7
- ,vh.lt)-i
I
U. 29299
kw
0.001
1.33^x10-5
U1D-10
O.CH75BO
.UM/6/
0.74S7
1 *9t,10-«
0 .001
Z.«»9»10-
ft. lb./«ec
0.73756
737.56
7.3756X10-"
12.^600
U7.i330»iu *•
51.457
550
U0034.IO-3
C. 737^6
»r /8«c
IxlO7
1,HJ'«>
1 .3-,5Bxl07
1.7i80xl08
980. 66i
6.9//OKlC»
7.457il00
l.*96iclG4
U107
2.,2->9<1U«
BTU/Bin
0.050M4
56.884
0.0/MZ4
5.688,10-9
5.5783x10 6
3.9685
42.4176
8.5096X10-5
0.056884
0.0!6t?
g. CB/MC
1.01»7»104
1.019/xlO7
I 3hZ6xlO^
1 «0197ji:10
1.7926x10*
7 • 1 146x1 0
7.6042llO6
15.254
1. Oi57xl04
2.9878,103
k CJ1/.I,
0.01433
14.331*
0.01.433
1.4331i;O~9
0.2520
1. 4056x10 -^
If .'88
2 I4J7K-0-'
0.01433
*.l»7,13->
1
, J41xlO 3 W.8
,-•410 6.6bxlJ*
l.S'eZxIU"3! SUb.28
1.34lOx:e-lf *.6B45xlO-i
O.C2157; 117M
1.3151XIU ' O.C65552
C. 0935^7 i 46636
49S12S
^ .0061x10-''^
;.341xlU~3 j 66(1
1791,10-4! 1V,.»(U
1
1000
1.3558
1.10-?
17.580 .
9 eo67 to-''
69.769
l.4M,lft-3
O.i92*9
BTLI/hr.
3.41304
3413 J)4
4.62T4
3.4130.10'7
M;
-4
238.11
2545.1
S.lOMilO"'
3.4130i
1
*£r>tlih Therai] l.'nITs (lean)
-------
CONVERSION FACTORS FOR VARIOUS SUBSTANCES3
Type of substance Conversion factors
Fuel
Oil
Natural gas
Gaseous Pollutants
°
so2
H2S
CO
HC (as methane)
Agricultaral products
Corn
Milo
Oats
Barley
Wheat
Cotton
Mineral products
Brick
Cement
Cement
Concrete
Mobile sources, fuel efficiency
Motor vehicles
Water born vessnls
Miscellaneous liquids
1 bbl - 159 liters (42 gal)
1 therm = 100,000 Btu (approx.
25000 kcal)
1 ppm, volune
1 ppm, volume =
I ppri, volume =
1 ppm, volume ;
I ppm, volume '
1 ppm, volume !
= 1960 MK/mJ
- 1880 Mg/m3
= 2610 />s,'/m3
= 1390 j-g/ra3
1.14 rag/ra3
0.654 rag/m3
1 bu = 25.4 kg = 56 Ib
1 bu - 25.4 kg - 56 IS
1 bu - 14.5 kg - 32 Ih
1 bu = 21.8 kg - 48 Ib
1 bu =• 27.2 kg = 60 Ib
1 bale - 226 kg - 500 Ib
1 hrlck " r . 5 v
1 bhl - 170 kp
1 yd3 = 1130 kg
I yd3 = 1820 kg
- 6.5 Ib
375 Ib
= 2500 Ib
» 4000 Ib
1.0 mi/gal = 0.426 km/liter
1.0 gal/naut ml = 2.05 liters/km
Reer
Paint
Varnish
Whiskey
Water
i bbl
1 gal
1 gal
1 bbl
1 g*i
= 31.5 gal
" 4.5 to 6.82 kg - 10 to
= 3.18 kg - 7 Ib
- 190 liters - 50.2 r,;1-!
= 3.81 kg = 8.3 Ib
15 Ib
aMany of the conversion factors \ n this table represent average values and
approximations ,>nd sone of the values vary with temperature and pressure.
These conversion factors should, however, be sufficiently accurate for
general field use.
A- 2 4
-------
4 TITLE ANQ SUBTITLE
COMPILATION OF AIR POLLl'TANT EMISSION FACTORS,
VOLUME I: STATIONARY POINT AND AREA SOURCES
9, PERFORMINO ORGANIZATION! .XJAME AND
Source Analysis Section, MDAD (MD 14)
Office Of Air Quality Planning A.id Standards
U. S. Environments1 Protection Agency
Research Triangle Park, NC 27711
TECHNICAL, REPORT DATA
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AP-42 Fourth Edition, Volume I
7 AUTHORIS)
|3 RbCIP'ENT'S ACLF.SSION NO.
i ........... .. -
J5 RtPORT RATE
i_Septernber 1935 ___
6 PERFORMING ORGANiZAT. ON CODt.
8 PE~B~rl5RMTN~G~ORf' ANjI JATION PfrPOi-
NO.
iO. PROGRAM '.LEMENT NO
|1t CONTRACT GRANT NJO
13. SPONSORING AGCNCV NAME AND AD3HESS
— I-
i13 rvrt Of hFPORT AND KIRICjD COVLRE D
14 SPONSORING AGENCY COUt
15. SUH^LEMENTARY NOTES
EPA Editor: Whitmel M. Joyner
16 ABSTRACT
Fmtssion dara obtained fron. source tests, material balance studies,
engineering estimates, etc., have been compiled for use by individuals and groups
responsible for conducting air pollution emission inventories. Emission factors
given in this document cover most of the common stationary and area source emission
categories.-: fuel combustion; combustion of solid wastes; evaporation of fuels;,
solvents and othfr volatile substances; various industrial processes; and
miscellaneous sources. When no specific source \.e3t dr.ra are available, these
factors can be used to esrlmate the quantities of pollutants being released fi'om a
source or source group.
Volume IT of this document provides emission lactors for mobile sources, both
on and off highway types. This information Is available from EPA's Office Of Mobile
Sources, 2565 Plymouth Road, Ann Arbor, KI 48105.
1 7.
C,i '.TiFlF ><;; O"! M I
COS A ri ! ,i i.i (.
Emissions
Emission Factors
Stationary Sources
Area Sources
Fuel Combustion
Emission Inventories
8(13
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