' "AP-42
FifthEdition
Supplement C
November 1997
SUPPLEMENT C
TO
COMPILATION
OF
AIR POLLUTANT
EMISSION FACTORS
VOLUME!:
STATIONARY POINT
AND AREA SOURCES
Office Of Air Quality Planning And Standards
Office Of Air And Radiation
U. S. Environmental Protection Agency
Research Triangle Park, NC 27711
November 1997
-------
This report has been reviewed by the Office Of Air Quality Planning And Standards, U. S. Environmental
Protection Agency, and has been approved for publication. Any mention of trade names or commercial products
is not intented to constitute endorsement or recommendation for use.
AP-42
Fifth Edition
Volume I
Supplement C
u
-------
Chap. 9, Sect. 5.1
Chap. 9, Sect. 6.1
Chap. 9, Sect. 9.6
Chap. 9, Sect. 10.1.1
Chap. 9, Sect. 10.1.2
Chap. 9, Sect. 12.3
Chap. 9, Sect. 15
Chap. 11, Sect. 3
Chap. 11, Sect. 14
Chap. 11, Sect. 23
Instructions For Inserting
Supplement C Of Volume I
Into AP-42
Meat Packing Plants
Natural and Processed Cheese
Bread Baking
Cane Sugar Processing'
Sugarbeet Processing
Distilled Spirits
Leather Tanning
Brick And Structural Clay
Product Manufacturing
Frit Manufacturing
Taconite Ore Processing
Replace [Work In Progress] sheet
Replace [Work In Progress]'sh'eet
Replace [Work In Progress] sheet
Replace [Work In Progress] sheet
Replace [Work hi Progress] sheet
Replace [Work hi Progress] sheet
Replace [Work In Progress] sheet
Replace entire
Replace entire
Replace entire
Section
NewJSe'ctibn"
New Section
New Section
New Section
New Section
New Section
Major Revision
Minor Revision
Major Revision
Insert new Technical Report Data Sheet.
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PUBLICATIONS IN SERIES
Issue
COMPILATION OF AIR POLLUTANT EMISSION FACTORS, FIFTH EDITION
SUPPLEMENT A
Introduction
Section 1.1
1.2
1.3
1.4
1.6
1.7
1.11
3.1
3.2
3.4
5.3
7.0
7.1
9.5.2
9.5.3
9.8.1
9.8.2
9.8.3
9.9.1
9.9.2
9.9.5
9.11.1
9.12.2
9.13.2
10.7
11.10
11.14
11.19
11.22
11.26
11.28
13.2.1
12.2.2
Appendix B.2
Date
1/95
11/96
Bituminous And Subbituminous Coal Combustion
Anthracite Coal Combustion
Fuel Oil Combustion
Natural Gas Combustion
Wood Waste Combustion In Boilers
Lignite Combustion
Waste Oil Combustion
Stationary Gas Turbines For Electricity Generation
Heavy-duty Natural Gas-fired Pipeline Compressor Engines
Large Stationary Diesel And All Stationary Dual-fuel Engines
Natural Gas Processing
Liquid Storage Tanks Introduction
Organic Liquid Storage Tanks
Meat Smokehouses
Meat Rendering Plants
Canned Fruits And Vegetables
Dehydrated Fruits And Vegetables
Pickles, Sauces And Salad Dressings
Grain Elevators And Processes
Cereal Breakfast Food
Pasta Manufacturing
Vegetable Oil Processing
Wines And Brandy
Coffee Roasting
Charcoal
Coal Cleaning
Frit Manufacturing
Construction Aggregate Processing
Diatomite Processing
Talc Processing
Vermiculite Processing
Paved Roads
UnpavedRoads
Generalized Particle Size Distributions
11/96
Publication In Series
in
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SUPPLEMENTS
Section
11/96
1.1 Bituminous And Subbituminous Coal Combustion
1.2 Anthracite Coal Combustion
1.3 Fuel Oil Combustion
1.4 Natural Gas Combustion
1.5 Liquefied Petroleum Gas Combustion :
1.6 Wood Waste Combustion In Boilers
1.7 Lignite Combustion
1.8 Bagasse Combustion In Sugar Mills
1.9 Residential Fireplaces
1.10 Residential Wood Stoves
1.11 Waste Oil Combustion
2.1 Refuse Combustion
3.1. Stationary Gas Turbines For Electricity Generation
3.2 Heavy-duty Natural Gas-fired Pipeline Compressor Engines
3.3 Gasoline And Diesel Industrial Engines
3.4 Large Stationary Diesel And All Stationary Dual-fuel Engines
6.2 AdipicAcid
9.7 Cotton Ginning ,
9.9.4 Alfalfa Dehydrating ,
9.12.1 Malt Beverages
11.7 Ceramic Products Manufacturing ' <
12.20 Electroplating
13.1 Wildfires And Prescribed Burning
14.0 Greenhouse Gas Biogenic Sources
14.1 Emissions From Soils—Greenhouse Gases
14.2 Termites—Greenhouse Gases
14.3 Lightning Emissions—Greenhouse
SUPPLEMENT C
Section
11/97
9.5.1 Meat Packing Plants :
9.6.1 Natural and Processed Cheese
9.9.6 Bread Baking
9.10.1.1 Cane Sugar Processing
9.10.1.2 Sugarbeet Processing
9.12.3 Distilled Spirits
9.15 Leather Tanning
11.3 Brick And Structural Clay Product Manufacturing
11.14 Frit Manufacturing
11.23 Taconite Ore Processing
IV
EMISSION FACTORS
11/96
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9.5.1 Meat Packing Plants
9.5.1.1 General1'2
The meat packing industry is made up of establishments primarily engaged in the slaughtering, for
their own account or on a contract basis for the trade, of cattle, hogs, sheep, lambs, calves, and vealers for
meat to be sold or to be used on the same premises in canning, cooking, curing, and freezing, and in making
sausage, lard, and other products. Also included in this industry are establishments primarily engaged in
slaughtering horses for human consumption.
3-7
9.5.1.2 Process Description'
The following sections describe the operations involved in beef processing, pork processing, and
other meat processing. Figure 9.5.1-1 provides a generic process flow diagram for meat packing operations.
9.5.1.2.1 Beef Processing3'7-
Animals are delivered from the market or farm to the meat plant and are placed in holding areas.
These holding areas should have adequate facilities for the inspection of livestock, including walkways over
pens, crushes, and other facilities. Sick animals and those unfit for human consumption are identified and
removed from the normal processing flow. Plants should have separate isolation and holding pens for these
animals, and may have separate processing facilities. The live beef animals are weighed prior to processing
so that yield can be accurately determined.
The animals are led from the holding area to the immobilization, or stunning, area where they are
rendered unconscious. Stunning of cattle in the U.S. is usually carried out by means of a penetrating or
nonpenetrating captive bolt pistol. Livestock for Kosher markets are not immobilized prior to
exsanguination.
The anesthetized animals are then shackled and hoisted, hind quarters up, for exsanguination
(sticking), which should be carried out as soon as possible after stunning. In cattle, exsanguination is effected
by severing the carotid artery and the jugular vein. Blood is collected through a special floor drain or
collected in large tunneled vats or barrels and sent to a rendering facility for further processing. More
information on rendering operations can be found in AP-42 Section 9.5.3, Meat Rendering Plants. Blood can
be used in human food only if it is kept completely sterile by removal from the animals through tubes or
syringes. ,
In some plants, electrical stimulation (ES) is applied to the carcasses to improve lean color, firmness,
texture, and marbling score; to improve bleeding of carcasses; and to make removal of the hides easier.
Electrical stimulation also permits rapid chilling by hastening the onset of rigor before temperatures drop to
the cold shortening range. If muscles reach temperatures below 15° to 16°C (59° to 61 °F) before they have
attained rigor, a contraction known as cold shortening occurs, which results in much less tender meat. In
some cases ES is applied to control the fall of pH value. Meat with a low pH value will be pale, soft, and
exudative (PSE meat). Meat with a high pH value may be dark, firm, and dry (DFD meat). It has been
claimed that ES enhances tenderness, primarily through the hastening of the onset of rigor and prevention of
cold shortening. Both high-voltage (>500 volts) and low-voltage (30 to 90 volts) ES systems can be used.
6/97 Food And Agricultural Industry 9.5.1-1
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VOC EMISSIONS
PM EMISSIONS
*
BLOOD
IMMOBILIZING
AND
EXSANGUINATION
PORK ONLY.
INED1BLES
INEDIBLES
SCALDING OR
SINGEING
DEHAIRING
HEADING AND
SHANKING
SIDING, OPENING, LEATHER
AND BACKING I H TANNING
1 •
EVISCERATING
AND SPLITTING
i
WASHING,
WEIGHING, AND »• VOC EMISSIONS
SANITIZING
1
CHILLING
1
BREAKDOWN
T T
SMOKING, CURING,
MATURING \ - -1 PROCESSING FOR
IVI/M UKINV, SPECIFIC PRODUCTS
PACKAGING
9.5.1-2
EMISSION FACTORS
6/97
-------
After exsanguination, the actual "dressing", or cleaning, of the carcasses begins. The first step is to
separate the esophagus from the trachea, called "rodding the weasand". Alternatively, this can be done after
the chest cavity has been opened. This separation aids in evisceration. After separation, a knot is made in the
esophagus, or a band is put around it to prevent the contents of the rumen (first stomach) from spilling and
contaminating the carcass.
Next, the skin is removed from the head, and the head is removed from the carcass by cutting through
the Adam's apple and the atlas joint (heading). The fore and hind feet are then removed to prevent
contamination of the carcass with manure and dirt dropped from the hooves (shanking or legging). Each of
the legs is then skinned.
The hide is then opened down the middle of the ventral side over the entire length of the carcass. The
hide is removed from the middle down over the sides (siding). Air or electrically powered rotary skinning
knives are often used to make skinning easier. Care is taken to avoid cutting or scoring the hide, as this
decreases its value for leather.
After siding, the carcass is opened (opening). First, a cut is made through the fat and muscle at the
center of the brisket with a knife. Then a saw is used to cut through the sternum. The hind quarters are
separated with a saw or knife. The tail is skinned and then removed two joints from the body. After
removing the tail, the hide is completely removed (backing). Hides are collected, intermediate preserving
operations performed, and the preserved hides sent to tanners for processing into leather. More information
on leather tanning processes can be found in AP-42 Section 9.15, Leather Tanning.
After the hide is removed, the carcass is eviscerated. With a knife, the abdomen of the carcass is
opened from top to bottom. The fat and membranes that hold the intestines and bladder in place are
loosened, and the ureters connecting the bladder and the kidneys are cut. The liver is removed for inspection.
The previously loosened esophagus is pulled up through the diaphragm to allow the abdominal organs to fall
freely into an inspection cart. The diaphragm membrane is cut and the thoracic organs are removed.
A handsaw or electric saw is used to cut through the exact center of the backbone to split the beef
carcass into sides (halving or splitting). Inedible material is collected and sent to a rendering plant for further
processing. More information on meat rendering processes can be found in AP-42 Section 9.5.3, Meat
Rendering Plants.
After dressing, the carcasses are washed to remove any remaining blood or bone dust. The carcasses
may also be physically or chemically decontaminated. The simplest physical decontamination method
involves spraying the carcass with high pressure hot water or steam. A variety of chemical decontaminants
may be used as well; acetic and lactic acids are the most widely used and appear to be the most effective. In
addition, the following may be used: the organic acids, adipic, ascorbic, citric, fumaric, malic, propionic, and
sorbic; aqueous solutions of chlorine, hydrogen peroxide, beta-propiolactone, and glutaraldehyde; and
inorganic acids, including hydrochloric and phosphoric.
After the carcasses are dressed and washed, they are weighed and chilled. A thorough chilling during
the first 24 hours is essential, otherwise the carcasses may sour. Air chillers are most common for beef sides.
A desirable temperature for chilling warm beef carcasses is 0°C (32°F). Because a group of warm carcasses
will raise the temperature of a chill room considerably, it is good practice to lower the temperature of the
room to 5° below freezing (-3°C [27 °F]) before the carcasses are moved in. Temperatures more severe than
this can cause cold shortening, an intense shortening of muscle fibers, which brings about toughening.
6/97 Food And Agricultural Industry 9.5.1-3
-------
Beef undergoes maturation and should be held for at least a week (preferably longer) at 0°C (32°F)
before butchery into retail joints. In the past, sides remained intact up to the point of butchery, but it is now
common practice to break down the carcasses into primal joints (wholesale cuts), which are then vacuum
packed. Preparation of primal joints in packing plants reduces refrigeration and transport costs, and is a
convenient pre-packing operation for retailers.
Some meat products are smoked or cured prior to market. More information on smoking and curing
processes can be found in AP-42 Section 9.5.2, Meat Smokehouses.
In the manufacture of frankfurters (hot dogs) and other beef sausages, a mix of ground lean meat and
ground fat are blended together; then spices, preservatives, extenders, and other ingredients are blended.with
the mixture. The mix is transferred to the hopper of the filling machine and fed to a nozzle by a piston pump.
The casing, either natural or artificial, is filled from the nozzle on a continuous basis and linked, either
manually or mechanically, to form a string of individual frankfurters or sausages.
9.5.1.2.2 Pork Processing3'7 -
Animals are delivered from the market or farm to the meat plant and are placed in holding areas.
These holding areas should have adequate facilities for the inspection of livestock, including walkways over
pens, crushes, and other facilities. Sick animals and those unfit for human consumption are identified and
removed from the normal processing flow. Plants should have separate isolation and holding pens for these
animals, and may have separate processing facilities. The live animals are weighed prior to processing so
that yield can be accurately determined.
Hogs must be rendered completely unconscious, in a state of surgical anesthesia, prior to being
shackled and hoisted for exsanguination. In large commercial operations, a series of chutes and restrainer
conveyers move the hogs into position for stunning. The V restrainer/conveyer, or similar system, is used in
most large hog processing operations. Hogs must be stunned with a federally acceptable device (mechanical,
chemical, or electrical). Mechanical stunning involves the use of a compression bolt with either a mushroom
head or a penetrating head. The force may be provided with compressed air or with a cartridge. Mechanical
stunning is largely confined to smaller operations. Chemical stunning involves the use of CO2, which reduces
blood oxygen levels, causing the animals to become anesthetized. Electrical stunning involves the use of an
electric current and two electrodes placed on the head.
Deep stunning, which was approved by the U.S. Department of Agriculture, Food and Safety
Inspection Service in 1985, requires more amperage and voltage and a third electrode attached to the back or
afoot Stunning causes the heart to stop beating (cardiac arrest). The stunned animals undergo
exsanguination (sticking) and blood collection in the same manner as described for cattle.
Hog carcasses, unlike cattle carcasses, generally are not skinned after exsanguination. Instead, the
carcasses are dropped into scalding water which loosens the hair for subsequent removal. The carcasses
should be kept under water and continually moved and turned for uniform scalding. In large plants, carcasses
enter the scalding tub and are carried through the tub by a conveyer moving at the proper speed to allow the
proper scalding time. During the hard-hair season (September-November), the water temperature should be
59° to 60°C (139° to 140°F) and the immersion period 4 to 4-1/2 minutes, while in the easy-hair season
(February-March), a temperature of 58°C (136°F) for 4 minutes is preferable. In small plants without
automation, hair condition is checked periodically during the scalding period; Some plants use an alternative
to scalding that involves passing the carcass through gas flames to singe the hair. The hair is then removed
by rotating brushes and water sprays, and the carcass is rinsed.
9.5.1-4
EMISSION FACTORS
6/97
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Various dehairing machines, sometimes called "polishers", are manufactured to remove hair from the
scalded pork carcasses. The dehairing process is begun with a dehairing machine, which uses one or more
cylinders with metal tipped rubber beaters to scour the outside of the carcasses. Hot water (60 ° C [ 140 ° F]) is
sprayed on the carcasses as they pass through the dehairer moving toward the discharge end. The carcasses
are removed from this machine, hand scraped, then hoisted again, hind quarters up. The carcasses are hand-
scraped again from the top (hind quarters) down. Any remaining hairs can be removed by singeing with a
propane or similar torch. Once the remaining hairs have been singed, the carcasses are scraped a final time
and washed thoroughly from the hind feet to the head. Some plants pass the carcasses through a singeing
machine, which singes any remaining hairs from the carcasses.
At one time, it was popular to dip dehaired carcasses into a hot solution (121° to 149°C [250° to
300°F]) of rosin and cottonseed oil for a period of six to eight seconds. When the rosin coating plasticized
after cooling, it was stripped by pull-rolling it down the carcass, taking with it the remaining hair, stubble,
and roots. However, in recent years, many packers have discontinued its use, turning instead to mechanical
brushes and torches to completely clean dehaired pork carcasses.
In some plants, hogs are skinned after exsanguination. The head and belly of the carcass are hand-
skinned, and the legs are either hand-skinned or removed. Then the carcass is hoisted, hind quarters up, and
placed under tension. A second hoist is connected to the loose head and leg skin and tightened to pull the
remaining skin from the carcass. The removed pigskins are trimmed, salted, folded, and stored in 50-gallon
drums.
After scalding and dehairing, singeing, or skinning, the head is severed from the backbone at the atlas
joint, and the cut is continued through the windpipe and esophagus. The head is inspected, the tongue is
dropped, and the head is removed from the carcass. The head is cleaned, washed, and an inspection stamp is
applied.
Following heading, the carcass is eviscerated. The hams are separated, the sternum is split, the
ventral side is opened down the entire length of the carcass, and the abdominal organs are removed. The
thoracic organs are then freed. All of the internal organs are inspected, those intended for human
consumption are separated, and the remainder are discarded into a barrel to be shipped to the rendering plant
As mentioned previously, more information on meat rendering can be found in AP-42 Section 9.5.3, Meat
Rendering Plants.
After evisceration, the carcass is split precisely in half. Glands and blood clots in the neck region are
removed, the leaf fat and kidneys are removed, and the hams are faced (a strip of skin and fat is removed to
improve appearance).
The carcass is then washed from the top down to remove any bone dust, blood, or bacterial
contamination. A mild salt solution (0.1 M KC1) weakens bacterial attachment to the carcass and makes the
bacteria more susceptible to the sanitization procedure, especially if the sanitizing solution is applied
promptly. Dilute organic acids (2 percent lactic acid and 3 percent acetic acid) are good sanitizers. In large
operations, carcass washing is automated. As the carcass passes through booths on the slaughter line, the
proper solutions are applied at the most effective pressure.
After washing and sanitizing, the carcass is inspected one final time, weighed, and the inspection
stamp is applied to each wholesale cut. The carcass is uien placed in a cooler at 0° to 1 °C (32° to 34°F)
with air velocity typically 5 to 15mph, equating to-5 °C (23 °F) wind chill, for a 24-hour chill period. For
thorough chilling, the inside temperature of the ham should reach at least 3 °C (37°F). With accelerated (hot)
processing, the carcass may be held (tempered) at an intermediate temperature of 16°C (60°F) for several
6/97 Food And Agricultural Industry . 9.5.1-5
-------
hours, or be boned immediately. When large numbers of warm carcasses are handled, the chill room is
normally precooled to a temperature several degrees below freezing -3 °C (27°F), bringing the wind chill to
-9°C (16°F) to compensate for the heat from the carcasses.
Spray chilling is permitted by the U.S.D.A. to reduce cooler shrink. Spray chilling solutions may
contain up to 5 ppm available chlorine, which acts a sanitizer. At least one plant sends carcasses directly
from the kill floor through a freezer, to produce a brightly colored pork with reduced carcass shrink.
Following cooling, pork carcasses are often divided into deboned primal joints for distribution. The primal
joints may be vacuum packed. To manufacture pork sausages, ground lean meat and ground fat are blended
together and processed in the same manner as that described for beef sausages in Section 9.5.1.2.1.
9.5.1.2.3 Other Meat Processing -
Other meats undergo processes similar to those described above for beef and pork processing. These
other meats include veal, lamb, mutton, goat, horse (generally for export), and farm-raised large game
animals. .
9.5.1.3 Emissions And Controls
No emission data quantifying VOC, HAP, or PM emissions from the meat packing industry were
identified during the development of this report. However, engineering judgment and comparison of meat
packing plant processes with similar processes in other industries may provide an estimation of the types of
emissions that might be expected from meat packing plant operations.
Animal holding areas, feed storage, singeing operations, and other heat sources (including boilers)
may be sources of PM and PM-10 emissions. Carbon dioxide stunning operations may be sources of CO2
emissions. Animal holding areas, scalding tanks, singeing operations, rosin dipping (where still used),
sanitizing operations, wastewater systems, and heat sources may be sources of VOC, HAP, and other criteria
pollutant emissions.
Potential emissions from boilers are addressed in AP-42 Sections 1.1 through 1.4 (Combustion).
Meat smokehouses, meat rendering operations, and leather tanning may be sources of air pollutant emissions,
but these sources are included in other sections of AP-42 and are not addressed in this section.
A number of VOC and particulate emission control techniques are potentially available to the meat
packing industry. These options include the traditional approaches of wet scrubbers, dry sorbants, and
cyclones. Other options include condensation and chemical reaction. No information is available for the
actual controls used at meat packing plants. The controls presented in this section are ones that theoretically
could be used. The specific type of control device or combination of devices would vary from facility to
facility depending upon the particular nature of the emissions and the pollutant loading in the gas stream.
The VOC emissions from meat packing operations are likely to be very low and associated with a high
moisture content
Control of VOC from a gas stream can be accomplished using one of several techniques, but the
most common methods are absorption, adsorption, and afterburners. Absorptive methods encompass all
types of wet scrubbers using aqueous solutions to absorb the VOC. The most common scrubber systems are
packed columns or beds, plate columns, spray towers, or other types of towers. Most scrubber systems
require a mist eliminator downstream of the scrubber.
Gas adsorption is a relatively expensive technique and may not be applicable to a wide variety of
pollutants. Adsorptive methods usually include one of four main adsorbents: activated carbon, activated
9.5.1-6 EMISSION FACTORS 6/97
-------
alumina, silica gel, or molecular sieves. Of these four, activated carbon is the most widely used for VOC
control, and the remaining three are used for applications other than pollution control.
Afterburners, or thermal incinerators, are add-on combustion control devices in which VOC's are
oxidized to CO2, water, sulfur oxides, and nitrogen oxides. The destruction efficiency of an afterburner is
primarily a function of the operating temperature and residence time at that temperature. A temperature
above 816 °C (1,500 °F) will destroy most organic vapors and aerosols.
Particulate control commonly employs methods such as venturi scrubbers, dry cyclones, wet or dry
electrostatic precipitators (ESPs), or dry filter systems. The most common controls are likely to be the
venturi scrubbers or dry cyclones. Wet or dry ESPs are used depending upon the paniculate loading of the
gas stream.
Condensation methods and scrubbing by chemical reaction may be applicable techniques depending
upon the type of emissions. Condensation methods may be either direct contact or indirect contact. The shell
and tube indirect method is the most common technique. Chemical reactive scrubbing may be used for odor
control in selective applications.
References for Section 9.5.1
1. Bureau of the Census, U. S. Department of Commerce, 1992 Census Of Manufactures, Industry
Series, MC92-I-20A, Meat Products, Industries 2011,2013, and 2015, Washington, D.C., U. S.
Government Printing Office, June 1995.
2. USDA, National Agricultural Statistics Service, Agricultural Statistics Board, 1995 Livestock
Slaughter Annual Summary, March 14,1996.
3. J. R. Romans, et al., The Meat We Eat, Thirteenth Edition, Interstate Publishers, Inc., Danville, IL,
1994.
4. M. D. Judge, et al., Principles Of Meat Science, Second Edition, Kendall/Hunt Publishing Company,
Dubuque, LA, 1989. .
5. A. H. Varnam and J. P. Sutherland, Meat And Meat Products, Technology, Chemistry, And
Microbiology, Chapman & Hall, New York, NY, 1995.
6. R. A. Lawrie, Meat Science, Fifth Edition, Pergamon Press, New York, NY, 1991.
7. N. R. P. Wilson, ed., Meat And Meat Products, Factors Affecting Quality Control, Applied Science
Publishers, Inc., Englewood, NJ, 1981.
6/97 Food And Agricultural Industry 9.5.1-7
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9.6.1 Natural And Processed Cheese
9.6.1.1 General1'3
The United States is one of the largest producers of cheese in the world. The total number of
industry establishments in the United States in 1995 was 432. In 1995, total natural cheese production in the
U. S., excluding cottage cheeses, was 6.9 billion pounds, and total processed cheese production was
2.3 billion pounds. Wisconsin is the leading producer of cheese in the United States, accounting for over 30
percent of all cheese production in the country.
Popular types of natural cheeses include unripened (e. g., cottage cheese, cream cheese), soft (e. g.,
Brie, Camembert), semi-hard (e. g., Brick, Muenster, Roquefort, Stilton), hard (e. g., Colby, Cheddar), blue
veined (e. g., Blue, Gorgonzola), cooked hard cheeses (e. g., Swiss, Parmesan), and pasta filata (stretched
curd, e. g., Mozzarella, Provolone). Examples of processed cheeses include American cheese and various
cheese spreads, which are made by blending two or more varieties of cheese or blending portions of the same
type of cheese that are in different stages of ripeness.
9.6.1.2 Process Description4"9
The modern manufacture of natural cheese consists of four basic steps: coagulating, draining, salting,
and ripening. Processed cheese manufacture incorporates extra steps, including cleaning, blending, and
melting. No two cheese varieties are produced by the same method. However, manufacturing different
cheeses does not require widely different procedures but rather the same steps with variations during each
step, the same steps with a variation in their order, special applications, or different ripening practices. -Table
9.6.1-1 presents variations in the cheesemaking process characteristic of particular cheese varieties. This
section includes a generic process description; steps specific to a single cheese variety are mentioned but are
not discussed in detail.
9.6.1.2.1 Natural Cheese Manufacture -
The following sections describe the steps in the manufacture of natural cheese. Figure 9.6.1-1
presents a general process diagram.
Milk Preparation -
Cow's milk is the most widely used milk in cheese processing. First, the milk is homogenized to
ensure a constant fat level. A standardizing centrifuge, which skims off the surplus fat as cream, is often used
to obtain the fat levels appropriate for different varieties of cheese. Following homogenization, the milk is
ready for pasteurization, which is necessary to destroy harmful micro-organisms and bacteria.
Coagulation -
Coagulation, or clotting of the milk, is the basis of cheese production. Coagulation is brought about
by physical and chemical modifications to the constituents of milk and leads to the separation of the solid part
of milk (the curd) from the liquid part (the whey). To initiate coagulation, milk is mixed with a starter, which
is a culture of harmless, active bacteria. The enzyme rennin is also used in coagulation. Most of the fat and
protein from the milk are retained in the curd, but nearly all of the lactose and some of the minerals, protein,
and vitamins escape into the whey. Table 9.6.1-1 provides the primary coagulating agents and the
coagulating times necessary for different varieties of cheese.
7/97 Food And Agricultural Industry 9.6.1-1
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EMISSION FACTORS
7/97
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MILK PREPARATION
(HOMEGENIZING,
PASTEURIZING)
1
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I
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Figure 9.6.1-1. Natural cheese manufacture.
(Source Classification Code in parentheses.)
7/97
Food And Agricultural Industry
9.6.1-3
-------
Curd Treatment-
After the curd is formed, it is cut into small pieces to speed whey expulsion and increase the surface
area. The curd particles are cut into various sizes, depending on the variety of cheese being made. Cutting
the curd into small cubes reduces the moisture content of the curd, whereas creating larger cubes increases the
moisture content
Following the cutting step, the curd is cooked, which contracts the curd particles and acts to remove
whey, develop texture, and establish moisture control. The cut curds and whey are heated and agitated.
Table 9.6.1-1 provides the cooking temperatures required to produce typical varieties of cheeses.
Curd Drainage -
The next step in cheese manufacture, drainage, involves separating the whey from the curd. Drainage
can be accelerated by either heat treatment or mechanical treatment, such as cutting, stirring, oscillating, or
pressing. After the curd is dry, it is cut into blocks which can then be filled into cheese hoops for further
draining and pressing. Table 9.6.1-1 gives the primary draining methods for a variety of cheeses.
For some cheeses, special applications and procedures occur immediately before, during, or after the
draining stage. For example, internally ripened, or blue veined, cheeses (e. g., Blue, Roquefort) are usually
seeded with penicillium powder prior to drainage. Cooked hard cheeses (e. g., Parmesan) are stirred and
warmed to accelerate and complete the separation of the whey. The separated whey may be treated and
disposed of; shipped offsite in liquid or concentrated form for use as animal feed; used to make whey cheese;
dried for lactose, mineral, or protein recovery; or dried for use as a food additive or use in the manufacture of
processed cheese.
Curd Knitting-
Knitting, or transforming, the curd allows the accumulating lactic acid to chemically change the curd;
knitting also includes salting and pressing. This step leads to the characteristic texture of different cheeses.
During the curd knitting stage, Provolone and Mozzarella cheeses are pulled and processed (these cheeses are
then kneaded, drawn, shaped, and smoothed); a bean gum or some other type of gum is added to cream cheese
to stabilize and stiffen it; and a creaming agent (cream and/or milk) is added to cottage cheese. During this
period, specific pH levels are controlled to produce different varieties of cheese (see Table 9.6.1-1).
To salt the cheese, coarse salt is spread over the surface of the cheese or the pressed cheese is
immersed in a salt solution. Salting further completes the drainage of the cheese and also affects rind
formation, growth of microorganisms, and enzyme activity. Table 9.6.1-1 provides the salting method and
salt percentage necessary to produce a particular variety of cheese.
Pressing determines the characteristic shape of the cheese by compacting the texture, extruding free
whey from the curds, and completing the curd knitting. Pressing involves confining the wet, warm curds in a
form or cloth bag. With some cheeses, vertical pressing is used; others require vacuum pressing to remove
occluded air and give a close-knit body. See Table 9.6.1-1 for the different pressing practices for various
cheeses.
Ripening -
During the ripening or curing stage, varieties of cheeses acquire their own unique textures, aromas,
appearances, and tastes through complex physical and chemical changes that are controlled as much as
possible by adjusting temperature, humidity, and duration of ripening. For all cheeses, the purpose of
ripening is to allow beneficial bacteria and enzymes to transform the fresh curd into a cheese of a specific
flavor, texture, and appearance. Cottage and cream cheeses are not ripened, and usually have a bland flavor
and soft body.
9.6.1-4
EMISSION FACTORS
7/97
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Some cheeses require the application of a special ripening agent to create a particular taste or texture.
For example, some cheeses rely wholly on surface bacteria and yeast applied to their exteriors for curing and
ripening (e. g., Brick, Brie, Camembert); others require injection of particular bacteria and molds (e. g., Blue)
or gas-forming microorganisms (e. g., Swiss). It is during the ripening stage that the rind or crust forms on
the cheese's surface. The rind controls the loss of moisture from the internal part of the cheese and regulates
the escape of gases released during ripening.
Preserving And Packaging -
Modern cheese packaging protects the food from microorganisms and prevents moisture loss.
Ripened cheeses must undergo special procedures during packaging for preservative reasons. Unripened
cheeses are packaged immediately after the curd is collected and must be immediately refrigerated.
Many ripened cheeses are coated in wax to protect them from mold contamination and to reduce the
rate of moisture loss. Cheeses that naturally develop a thick, tightly woven rind, such as Swiss, do not require
waxing. A second method of ripened cheese packaging involves applying laminated cellophane films to
unwaxed cheese surfaces. The most common packaging film consists of two laminated cellophane sheets and
a brown paper overlay necessary for shipping. A variation includes a metal foil wrap.
9.6.1.2.2 Processed Cheese Manufacture -
Nearly one-third of all cheese produced in the United States consists of processed cheese and
processed cheese products. There are many different types of final products in processed cheese manufacture.
These cheeses are distinguished from one another not only by their composition but by their presentation as
individual portions, individual slices, rectangular blocks, or special presentation as cylinders or tubes.
Processed cheese is made by pasteurizing, emulsifying, and blending natural cheese. Processed
cheese foods, spreads, and cold pack cheeses contain additional ingredients, such as nonfat milk solids and
condiments. Several varieties of natural cheeses may be mixed, and powdered milk, whey, cream or butter,
and water may be added. The following section describes the basic steps necessary for producing pasteurized
process cheese, the most common processed cheese.
Pasteurized Process Cheese -
Cheeses are selected to be processed from both mild and sharp cheeses. For example, American
cheese is made from Cheddar and Colby cheeses. Once selected, the cheeses must be analyzed for their fat
and moisture contents to determine the proper amount of emulsifiers and salts to be added. Cheese surfaces
are cleaned by scraping and trimming, and the rinds are removed. After cleaning, the cheese blocks are
ground in massive grinders, combined, and the cheese mixture is heated. At this point, the melted cheese
separates into a fat and serum. Emulsifiers are added to disperse the fat, and create a uniform, homogenous
mass.
The molten cheese is removed quickly from the cookers and is pumped or dropped into packaging
hoppers. The cheese is packaged in the absence of oxygen to inhibit the growth of mold. The cheese is
usually wrapped in lacquered aluminum foil or in aluminum foil-lined cardboard or plastic boxes. For sliced
processed cheese, the molten cheese is spread uniformly by chilled steel rollers and cut by rotary knives to
consumer size.
7/97 Food And Agricultural Industry 9.6.1-5
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Processed Cheese Foods -
Other processed cheeses that are similar to the above in manufacturing are also commonly produced.
For example, to produce pasteurized process cheese food, one or more of the following optional dairy
ingredients are added: cream, milk, skim milk, buttermilk, and/or cheese whey. The result is a processed
cheese food that is higher in moisture and lower in fat than pasteurized process cheese. After heating,
processed cheese intended for spreading undergoes a creaming step, which includes mechanical kneading of
the hot cheese and addition of various dairy products and other additives. Other processed cheese products
include cold-packed cheese, cold-packed cheese food, and reduced fat cheeses. All processed cheeses may be
enhanced with salt, artificial colorings, spices or flavorings, fruits, vegetables, and meats.
Grated and powdered cheeses are produced by removing the moisture from one or more varieties of
cheeses and grinding, grating, or shredding the cheese(s). Mold-inhibiting ingredients and anti-caking agents
may be added as well. Dehydration takes such forms as tray drying, spray or atomized drying, and freeze
drying. Popular types of grated cheese include Parmesan, Romano, Mozzarella, and Cheddar. Cheese
powders, such as those made from Cheddar cheese, may be used to flavor pasta, or added to bread dough,
potato chips, or dips.
9.6.1.3 Emissions And Controls
Particulate emissions from cheese manufacture occur during cheese or whey drying, and may occur
when the cheese is grated or ground before drying. CO2 emissions from direct-fired dryers are primarily from
the combustion of fuel, natural gas. Cheese dryers are used in the manufacture of grated or powdered
cheeses. Whey dryers are used in some facilities to dry the whey after it has been separated from the curd
following coagulation. VOC emissions may occur in the coagulation and/or ripening stages. Particulate
emissions from cheese and whey dryers are controlled by wet scrubbers, cyclones, or fabric filters. Cyclones
are also used for product recovery. Emission factors for cheese drying and whey drying in natural and
processed cheese manufacture are shown in Table 9.6.1-2.
Table 9.6.1-2. PARTICULATE EMISSION FACTORS FOR NATURAL AND
PROCESSED CHEESE MANUFACTURE3
Source
Cheese dryer
(SCC 3-02-030-20)
Whey dryer
(SCC 3-02-030-10)
Pollutant
Filterable PM
Condensible inorganic PM
Condensible organic PM
Filterable PM
Condensible PM
Average emission factor^
Ib/ton
2.5
0.29
0.44
1.24
0.31
Rating
D
D
D
D
D
Ref.
1,2,3
2,3
1,2,3
4,6,7
4,6,7
Emission factor units are Ib/ton of dry product. To convert from Ib/ton to kg/Mg, multiply by 0.5. SCC = Source
Classification Code.
Emission factors for cheese dryers represent average values for controlled emissions based on wet scrubbers or
venturi scrubbers. Factors for whey dryers are average values for controlled emissions based on cyclones, wet
scrubbers, or fabric filters.
9.6.1-6
EMISSION FACTORS
7/97
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References For Section 9.6.1 ,
1. 1992 Census Of Manufactures: Dairy Products, U. S. Department of Commerce, Bureau of Census,
Washington, DC, 1994.
2. U. S. Department of Agriculture, National Agriculture Statistics Service, Dairy Products 1995
Summary, Washington, DC, April 1996. http://usda.mannlib.cornell.edu/reports
3. B. Battistotti, et al., Cheese: A Guide To The World Of Cheese And Cheesemaking, Facts On File
Publications, NY, 1984.
4. A. Eck, ed., Cheesemaking: Science And Technology, Lavoisier Publishing, New York, 1987.
5. A. Meyer, Processed Cheese Manufacture, Food Trade Press Ltd., London, 1973.
6. Newer Knowledge Of Cheese And Other Cheese Products, National Dairy Council, Rosemont, IL,
1992.
7. M.E. Schwartz, Cheesemaking Technology, Noyes Data Corporation, Park Ridge, NJ, 1973.
8. F. Kosikowski, Cheese And Fermented Milk Foods, Edwards Brothers, Ann Arbor, MI, 1977.
9. New Standard Encyclopedia, Vol.4, "Cheese", Standard Educational Corporation, Chicago, IL,
pp. 238-240.
7/97 Food And Agricultural Industry 9.6.1-7
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9.9.6 Bread Baking
USEPA Recommendation for Estimating VOC Emissions from Bread Bakeries
The Emissions Inventory Branch recommends the equation given in "Alternative Control
Technology Document for Bakery Oven Emissions" (EPA 453/R-92-017, December 1992) for
estimating VOC emissions from yeast-raised bread baking point sources. The
equation is:
VOC E.F. = 0.95Yi+0.195ti-0.51S-0.86ts+1.90
where
VOC E.F. = pounds VOC per ton of baked bread
Yi = initial baker's percent of yeast
ti = total yeast action time in hours
S = final (spike) baker's percent of yeast
ts = spiking time in hours
This equation will be incorporated into a future revision of AP-42 section 9.9.6. Full details on
the derivation and use of the equation are contained in the ACT document cited above. Copies of
the ACT document are available - as supplies permit - from the Library Services Office (MD-35), U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina 27711. It is also
available for $27.00 (stock number PB93-157618) from the National Technical Information Service,
5285 Port Royal Road, Springfield, Virginia 22161, phone (800) 553-6847.
2/97 Food And Agricultural Industries 9.9.6-1
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9.10.1.1 Cane Sugar Processing
9.10.1.1.1 General1'3
Sugar cane is burned in the field prior to harvesting to remove unwanted foliage as well as to
control rodents and insects. Harvesting is done by hand or, where possible, by mechanical means.
After harvesting, the cane goes through a series of processing steps for conversion to the final
sugar product. It is first washed to remove dirt and trash, then crushed and shredded to reduce the
size of the stalks. The juice is next extracted by 1 of 2 methods, milling or diffusion. In milling, the
cane is pressed between heavy rollers to squeeze out the juice; in diffusion, the sugar is leached out by
water and thin juices. The raw sugar then goes through a series of operations including clarification,
evaporation, and crystallization in order to produce the final product. The fibrous residue remaining
after sugar extraction is called bagasse.
All mills fire some or all of their bagasse in boilers to provide power necessary in their milling
operation. Some, having more bagasse than can be utilized internally, sell the remainder for use in the
manufacture of various chemicals such as furfural.
9.10.1.1.2 Emissions2'3
The largest sources of emissions from sugar cane processing are the openfield burning in the
harvesting of the crop, and the burning of bagasse as fuel. In the various processes of crushing,
evaporation, and crystallization, relatively small quantities of particulates are emitted. Emission factors
for sugar cane field burning are shown in Table 2.5-2. Emission factors for bagasse firing in boilers
are included in Section 1.8.
References For Section 9.10.1.1
1. "Sugar Cane," In: Kirk-Othmer Encyclopedia Of Chemical Technology, Vol. IX, New York,
John Wiley and Sons, Inc., 1964.
2. E. F. Darley, "Air Pollution Emissions From Burning Sugar Cane And Pineapple From
Hawaii", In: Air Pollution From Forest And Agricultural Burning, Statewide Air Pollution
Research Center, University of California, Riverside, California, Prepared for the U. S.
Environmental Protection Agency, Research Triangle Park, NC, 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, FL, Prepared
for the U. S. Environmental Protection Agency, Research Triangle Park, NC, under Contract
No. CPA 70-142, Task Order 9c, July 15, 1971.
4/76 (Reformatted 1/95) Food And Agricultural Industries 9.10.1.1-1
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9.10.1.2 Sugarbeet Processing
9.10.1.2.1 General1'2
Sugarbeet processing is the production of sugar (sucrose) from sugarbeets. Byproducts of
sugarbeet processing include pulp and molasses. Most of the molasses produced is processed further to
remove the remaining sucrose. The pulp and most of the remaining molasses are mixed together, dried,
and sold as livestock feed.
9.10.1.2.2 Process Description1"4
Figures 9.10.1.2-1 and 9.10.1.2-2 are flow diagrams for a typical sugarbeet processing plant.
Figure 9.10.1.2-1 shows preprocessing and livestock feed production operations, and Figure 9.10.1.2-2
shows the beet sugar production operations. Mechanically harvested sugarbeets are shipped to processing
plants, where they are typically received by high-speed conveying and screening systems. The screening
systems remove loose dirt from the beets and pinch the beet tops and leaves from the beet roots. The
conveyors transport the beets to storage areas and then to the final cleaning and trash removal operations
that precede the processing operations. The beets are usually conveyed to the final cleaning phase using
flumes, which use water to both move and clean the beets. Although most plants use flumes, some plants
use dry conveyors in the final cleaning stage. The disadvantage of flume conveying is that some sugar
leaches into the flume water from damaged surfaces of the beets. The flumes carry the beets to the beet
feeder, which regulates the flow of beets through the system and prevents stoppages in the system. From
the feeder, the flumes carry the beets through several cleaning devices, which may include rock catchers,
sand separators, magnetic metal separators, water spray nozzles, and trash catchers. After cleaning, the
beets are separated from the water, usually with a beet wheel, and are transported by drag chain, chain
and bucket elevator, inclined belt conveyor, or beet pump to the processing operations.
Sugarbeet processing operations comprise several steps, including diffusion, juice purification,
evaporation, crystallization, dried-pulp manufacture/and sugar recovery from molasses. Descriptions of
these operations are presented in the following paragraphs.
Prior to removal of the sucrose from the beet by diffusion, the cleaned and washed beets are sliced
into long, thin strips, called cossettes. The cossettes are conveyed to continuous diffusers, in which hot
water is used to extract sucrose from the cossettes. In one diffuser design, the diffuser is slanted upwards
and conveys the cossettes up the slope as water is introduced at the top of the diffuser and flows
countercurrent to the cossettes. The water temperature in the diffuser is typically maintained between 50°
and 80°C (122° and 176°F). This temperature is dependant on several factors, including the
denaturization temperature of the cossettes, the thermal behavior of the beet cell wall, potential enzymatic
reactions, bacterial activity, and pressability of the beet pulp. Formalin, a 40 percent solution of
formaldehyde, was sometimes added to the diffuser water as a disinfectant but is not used at the present
time. Sulfur dioxide, chlorine, ammonium bisulfite, or commercial FDA-approved biocides are used as
disinfectants. The sugar-enriched water that flows from the outlet of the diffuser is called raw juice and
contains between 1.0 and 15 percent sugar. This raw juice proceeds to the juice purification operations.
The processed cossettes, or pulp, leaving the diffuser are conveyed to the dried-pulp manufacture
operations.
3/97 Food And Agricultural Industry ' 9.10.1.2-1
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9.10.1.2-3
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In the juice purification stage, non-sucrose impurities in the raw juice are removed so that the pure
sucrose can be crystallized. First, the juice passes through screens to remove any small cossette particles.
Then the mixture is heated to 80° to 85°C (176° to 185°F) and proceeds to the first carbonation tank. In
some processes, the juice from the screen passes through a pre-limer, heater, and main limer prior to the
first carbonation tank. In the first carbonation tank, milk of lime [Ca(OH)2] is added to the mixture to
adsorb or adhere to the impurities in the mixture, and carbon dioxide (CO2) gas is bubbled through the
mixture to precipitate the lime as insoluble calcium carbonate crystals. Lime kilns are used to produce the
C02 and lime used in carbonation; the lime is converted to milk of lime in a lime slaker. The small,
insoluble crystals (produced during carbonation) settle out in a clarifier, after which the juice is again
treated with CO2 (in the second carbonation tank) to remove the remaining lime and impurities. The pH
of the juice is lower during this second carbonation, causing large, easily filterable, calcium carbonate
crystals to form. After filtration, a small amount of sulfur dioxide (SO^ is added to the juice to inhibit
reactions that lead to darkening of the juice. Most facilities purchase SO2 as a liquid but a few facilities
produce SO2 by burning elemental sulfur in a sulfur stove. Following the addition of SO2, the juice
(known as thin juice) proceeds to the evaporators.
The evaporation process, which increases the sucrose concentration in the juice by removing
water, is typically performed in a series of five evaporators. Steam from large boilers is used to heat the
first evaporator, and the steam from the water evaporated in the first evaporator is used to heat the second
evaporator. This transfer of heat continues through the five evaporators, and as the temperature decreases
(due to heat loss) from evaporator to evaporator, the pressure inside each evaporator is also decreased,
allowing the juice to boil at the lower temperatures provided in each subsequent evaporator. Some steam
is released from the first three evaporators, and this steam is used as a heat source for various process
heaters throughout the plant. After evaporation, the percentage of sucrose in the "thick juice" is
50-65 percent. Crystalline s'ugars, produced later in the process, are added to the juice and dissolved in
the high melter. This mixture is then filtered, yielding a clear liquid known as standard liquor, which
proceeds to the crystallization operation.
Sugar is crystallized by low-temperature pan boiling. The standard liquor is boiled in vacuum
pans until it becomes supersaturated. To begin crystal formation, the liquor is either "shocked" using a
small quantity of powdered sugar or is "seeded" by adding a mixture of finely milled sugar and isopropyl
alcohol. The seed crystals are carefully grown through control of the vacuum, temperature, feed-liquor
additions, and steam. When the crystals reach the desired size, the mixture of liquor and crystals, known
as massecuite or fillmass, is discharged to the mixer. From the mixer, the massecuite is poured into high-
speed centrifugals, in which the liquid is centrifuged into the outer shell, and the crystals are left in the
inner centrifugal basket. The sugar crystals are then washed with pure hot water and are sent to the
granulator, which is a combination rotary drum dryer and cooler. Some facilities have separate sugar
dryers and coolers, which are collectively called granulators. The wash water, which contains a small
quantity of sucrose, is pumped to the vacuum pans for processing. After cooling, the sugar is screened
and then either packaged or stored in large bins for future packaging.
The liquid that was separated from the sugar crystals in the centrifugals is called syrup. This
syrup serves as feed liquor for the "second boiling" and is introduced back into the vacuum pans along
with standard liquor and recycled wash water. The process is repeated once again, resulting in the
production of molasses, which can be further desugarized using an ion exchange process called deep
molasses desugarization. Molasses that is not desugarized can be used in the production of livestock feed
or for other purposes.
Wet pulp from the diffusion process is another product of sugarbeet processing. The pulp is first
pressed, typically in horizontal double-screw presses, to reduce the moisture content from about 95 percent
9.10.1.2-4 EMISSION FACTORS 3/97
-------
to about 75 percent. The water removed by the presses is collected and used as diffusion water. After
pressing, molasses is added to the pulp, which is then dried in a direct-fired horizontal rotating drum
known as a pulp dryer. The pulp dryer, which can be fired by oil, natural gas, or coal, typically provides
entrance temperatures between 482° and 927° C (900° and 1700°F). As the pulp is dried, the gas
temperature decreases and the pulp temperature increases. The exit temperature of the flue gas is typically
between 88° and 138°C (190° and 280°F). The resulting product is usually pelletized, cooled, and sold as
livestock feed.
9.10.1.2.3 Emissions And Controls1'3-4 . . •
Participate matter (PM), combustion products, and volatile organic compounds (VOC) are the
primary pollutants emitted from the sugarbeet processing industry. The pulp dryers, sugar granulators and
coolers, sugar conveying and sacking equipment, lime kilns and handling equipment, carbonation tanks,
sulfur stoves, evaporators, and boilers, 'as well as several fugitive sources are potential emission sources.
Potential emissions from boilers are addressed in AP-42 Sections 1.1 through 1.4 (Combustion) and those
from lime kilns are addressed in AP-42 Section 11.17, Lime Manufacturing. Potential sources of PM
emissions include the pulp dryer, sugar granulators and coolers, sugar conveying and sacking equipment,
sulfur stove, and fugitive sources. Fugitive sources include unpaved roads, coal handling, and pulp
loading operations. Although most facilities purchase SO2, a few facilities still use sulfur stoves. The
sulfur stove is a potential source of SO2 emissions, and the pulp dryers may be a potential source of
nitrogen oxides (NOX), SO2, CO2, carbon monoxide (CO), and VOC. Evaporators may be a potential
source of C02, ammonia (NH^, SO2, and VOC emissions from the juice. However, only the first three
of five evaporators (in a typical five-stage system) release exhaust gases, and the gases are used as a heat
source for various process heaters before release to the atmosphere. Emissions from carbonation tanks are
primarily water vapor but contain small quantities of NH3, VOC, and may also include CO2 and other
combustion gases from the lime kiln. There are no emission test data available, for ammonia emissions
from carbonation tanks.
Particulate matter emissions from pulp dryers are typically controlled by a cyclone or multiclone
system, sometimes followed by a secondary device such as a wet scrubber or fabric filter. Particulate
matter emissions from granulators are typically controlled with wet scrubbers, and PM emissions from
sugar conveying and sacking as well as lime dust handling operations are controlled by hood systems that
duct the emissions to fabric filtration systems. Emissions from carbonation tanks and evaporators are not
typically controlled.
Table 9.10.1.2-1 presents emission factors for filterable PM, PM-10, and condensible PM
emissions from sugarbeet processing operations. Table 9.10.1.2-2 presents emission factors for volatile
organic compounds (VOC), methane, NOX, SO2, CO, and CO2 emissions from sugarbeet processing
operations, and Tables 9.10.1.2-3 and 9.10.1.2-4 present emission factors for organic pollutants emitted
from coal-fired dryers, carbonation tanks, and first evaporators.
3/97 Food And Agricultural Industry ' 9.10.1.2-5
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o d 22
• P
|t-( Q £-4
P P
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"* •* ^-.
0 0 P
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p
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p
P .
2
i
P
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§
p
2
P -
§ 1
P CQ
&
TJ< CO
Tj3 CJ
None
Multiclone
Coal-fired pulp dryer1'
(SCC 3-02-016-01)
p
p
O3
o
Wet scrubber
P P
2 2
P P
§ 2
O 0
Multiclone11
Wet scrubber
0>
•e
Natural gas-fired pulp
(SCC 3-02-016-08)
g S Q Q
2 0- 22
O P P P
O CO
^P i— ( CO O
•- -H 00
1 g •=& -a -a t.
„ -§J o-iwicsi
S ill |1 Ifl
U (_)8^;^;uS5?&
fe
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*V co g co
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te< oo
p p p
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P P
LO
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o' o 2
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J° DO «>
9 •§ 9
MS • g g
8« § gp^
°U "20
w>°2- So g| co,
CO CO
P
2
i
1
1 Sulfur stove
(SCC 3-02-016-31)
§
1
1
1 Pellet Cooler
(SCC 3-02-016-16)
§
i
I
to
CO
0
<3 CN1
g^co,
O)
-------
.
*i
c
8
«—4
1
CM
CD
f
O5
13
S
CL,
&
a
1
a
g
1
1
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oo O H
13
^
2;ao
W f— 1 M
§^K
Wfc
y
1
Js
**J
pi
1<§
W
o
1
|
iMISSION
FACTOR
RATING
-o
.— i
2DiO
|§|
S **• a
pjf-
§
«1
~pL o
HO
§'
S
c?
Q
2
§
•
Q
^
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2
§
g
o
S
Cvi
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CN3
CD
tj CO
S c/:
P£^
O
»{
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o
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CO
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CO
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1
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2
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c
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1
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1
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G
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1
*£\
• ^H
§
| t
2
o
42
(jj
«
1
o
G
Q
2
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^
issification
CO
0
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•^
^
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^
s
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f]
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0
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1
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eference 1
eferences
/^^ rv^
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i
o
CO
o
G
Q
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w
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*t-H
c
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eference 2
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i
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o
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CJ
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G
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00
eference 1
DH
tn
3/97
Food and Agricultural Industry
9.10.1-7
-------
Table 9.10.1.2-2. EMISSION FACTORS FOR VOC( METHANE, AND INORGANIC
POLLUTANT EMISSIONS FROM SUGARBEET PROCESSING OPERATIONSa
EMISSION FACTOR RATING: D
Source
Coal-fired pulp dryerc
(SCC 3-02-016-01)
Natural gas-fired pulp dryerc
(SCC 3-02-016-08)
Fuel oil-fired pulp dryerc
(SCC 3-02-016-05)
First evaporator
(SCC 3-02-016-41)
Sulfur stove
(SCC 3-02-01 6-31)
First carbonation tank
(SCC 3-02-016-21)
Second carbonation tank
(SCC 3-02-016-22)
Ib/ton
vocb
1.2d
ND
0.1 lJ
ND
ND
ND
ND
Methane
ND
ND
0.028J
ND
" ND
• ND
ND
NOY
0.66e
ND
0.60J
ND
ND
ND.
ND
SO?
0.79f
ND
1.0k
ND .
ND
ND
ND
CO
2.3d-
ND
. 1.0)
..;- ND
;'ND ' ;
'.I ND
ND
CO,
370§
156h
43'0m
ND
•ND
,ND
. ND
a Emission factor units are Ib/ton of .pressed wet pulp to the dryer, unless noted. Factors represent
uncontrolled emissions unless noted. To convert from Ib/ton to kg/Mg, multiply by 0.5. * "
SCC = Source Classification Code. ND == no data.
b Volatile organic compounds as methane.
c Data for pulp dryers equipped with cyclones, multiclones, wet scrubbers, or a combination of these
control technologies are averaged together because these control technologies are not specifically
designed to control VOC, methane, NOX< SO2, CO, or CO2 emissions. ;
d Reference 19.
e References 16,19.
f References 7,19. .. - '
8 References 7,13,16-17,19,21. EMISSION FACTOR RATING: B. ;
h References 8-12,22-23,25. EMISSION FACTOR RATING: C.
J Reference 4.
^ References 14-15.
m References 4-6,14,24. EMISSION FACTOR RATING: C.
9.10.1.2-8
EMISSION FACTORS
3/97
-------
Table 9.10.1.2-3. EMISSION FACTORS FOR ORGANIC POLLUTANT EMISSIONS
FROM PULP DRYERS3
EMISSION FACTOR RATING: E
Source
Coal-fired pulp dryer with wet
scrubber
(SCC 3-02-016-01)
Pollutant
CASRN
75-07-0
107-02-8
123-73-9
50-00-0
91-57-6
88-75-5
95-48-7
105-67-9
106-44-5
100-02-7
208-96-8
100-52-7
65-85-0
100-51-6
117-81-7
84-74-2
132-64-9
84-66-2
91-20-3
98-95-3
85-01-8
108-95-2
Name
Acetaldehyde
Acrolein
Crotonaldehyde
Formaldehyde
2-methylnaphthalene
2-nitrophenol
2-methylphenol
2 , 4-dimethylphenol
4-methylphenol
4-nitrophenol
Acenaphthylene
Benzaldehyde
Benzoic acid
Ben2yl alcohol
Bis(2-ethylhexyl)phthalate
Di-n-butylphthalate
Dibenzofuran
Diethylphthalate
Naphthalene
Nitrobenzene
Phenanthrene
Phenol
Emission
Factor,
Ib/ton
0.015
0.0076
0.0020
0.0071
1.7xlO-5
0.00018
3.4xlO-5
2.5xlO-5
0.00013
0.00014
1.7xlO-6
0.0014
0.0028
7.1xlO-5
0.0015
5.2xlO'5
l.lxlO-5
9.8xlO'6
0.00011
1.9xlO-5
1.2xlO'5 .
0.00032
a Reference 3. Emission factor units are Ib/ton of pressed wet pulp to the dryer. To convert from Ib/ton
to kg/Mg, multiply by 0.5. SCC = Source Classification Code. CASRN = Chemical Abstracts Service
Registry Number.
3/97
Food And Agricultural Industry
9.10.1.2-9
-------
Table 9.10.1.2-4. EMISSION FACTORS FOR ORGANIC POLLUTANT EMISSIONS
FROM CARBONATION TANKS AND EVAPORATORS3
Source
First carbonation tankb
(SCC 3-02-016-21)
Second carbonation tankb
(SCC 3-02-016-22)
First evaporator0
(SCC 3-02-016-41)
-
Pollutant
CASRN
91-57-6
51-28-5
106-44-5
83-32-9
100-52-7
65-85-0
100-51-6
117-81-7
91-20-3
85-01-8
108-95-2
75-07-0
107-02-8
123-73-9
50-00-0
75-07-0
107-02-8
123-73-9
50-00-0
106-44-5
100-52-7
65-85-0
100-51-6
117-81-7
84-74-2
132-64-9
84-66-2
78-59-1
91-20-3
85-01-8
108-95-2
110-86-1
Name
2-methylnaphthalene
2,4-dinitrophenol
4-methylphenol
Acenaphthene
Benzaldehyde
Benzoic acid
Benzyl alcohol
Bis(2-ethylhexyl)phthalate
Naphthalene
Phenanthrene
Phenol '
Acetaldehyde
Acrolein
Crotonaldehyde ,
Formaldehyde
Acetaldehyde
Acrolein
Crotonaldehyde
Formaldehyde
4-methylphenol
Benzaldehyde
Benzoic acid
Benzyl alcohol
Bis(2-ethylhexyl)phthalate
Di-n-butylphthalate
Dibenzofuran
Diethylphthalate
Isophorone
Naphthalene
Phenanthrene
Phenol
Pyridine
Emission Factor,
lb/l,OOORal
5.1xlO-7
ND
,6.6xlO-7
ND
l.lxlO-4
8.4xlO-6
5.0xlO'6
1.2xlO-5
2.0xlO-6
1.4xlO-6
1.3xlO-6
0.0043
2.4xlO'4
S.OxlQ-5
1.6xlO-5
6.7x1 0-5
4.2xlO-7
1.4xlO-7
7.0xlO-7
ND
2.2xlO-6
ND
1.8xlO-7
SJxlO'7
LlxlO'9
ND
ND
ND ;
2.5xlO-8
1.6X10'8
1.2xlO-8
3.4xlO-8
EMISSION
FACTOR
RATING
D
D
D
D
D
D
D
D
D
D
D
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
'.E
E
E
E
a Reference 3. SCC = Source Classification Code. CASRN = Chemical Abstracts Service Registry
Number. ND = no data.
b Emission factor units are Ib per 1,000 gallons of raw juice produced.
c Emission factor units are Ib per 1,000 gallons of thin juice produced.
9.10.1.2-10
EMISSION FACTORS
3/97
-------
REFERENCES FOR SECTION 9.10.1.2
1. R.A. McGinnis, Beet-Sugar Technology, Third Edition, Beet Sugar Development Foundation, Fort
Collins, CO, 1982.
2. The Beet Sugar Story, United States Beet Sugar Association, Washington, D.C., 1-959.
3. Particulate, Aldehyde, And Semi-Volatile Organic Compound (SVOC) Testing Report For The Pulp
Dryer Stacks, 1st And 2nd Carbonation Tank Vents, And The Evaporator Heater Vents, The
Amalgamated Sugar Company, Nampa, ID, May 14, 1993.
4. Emission Performance Testing Of Four Boilers, Three Dryers, And One Cooler—Holly Sugar
Corporation, Santa Maria, California, Western Environmental Services, Redondo Beach, CA,
June 1991.
5. Results Of A Source Emission Compliance Test At Southern Minnesota Beet Sugar Cooperative,
Renville, Minnesota, MMT Environmental, Inc., St. Paul, MN, January 21, 1988.
6. Results Of An Emission Compliance Test On The North Dryer #2 At Southern Minnesota Beet
Sugar Cooperative, Renville, Minnesota, MMT Environmental, Inc., St. Paul, MN,
December 14, 1988.
7. Results Of A Source Emission Compliance Test At Minn-Dak Farmers Cooperative, Wahpeton,
North Dakota, MMT Environmental, Inc., St. Paul, MN, November 1, 1983.
8. Particulate Emission Testing Performed For Monitor Bay Sugar Company, Bay City, Michigan, On
The Pulp Dryer 3 Exhaust, Network Environmental, Inc., Grand Rapids, MI, October 12, 1992.
9. Particulate Emission Testing Performed For Monitor Bay Sugar Company, Bay City, Michigan, On
The Pulp Dryer 2 Exhaust, Network Environmental, Inc., Grand Rapids, MI, October 13, 1992.
10. Particulate Emission Testing Performed For Monitor Bay Sugar Company, Bay City, Michigan, On
The Pulp Dryer 1 Exhaust, Network Environmental, Inc., Grand Rapids, MI, October 14, 1992.
11. Emissions Survey Conducted At Western Sugar Company's BiUings, Montana, Production Facility,
American Environmental Testing Company, Inc., December 1988.
12. EPA Method 5 Particulate Emissions Tests Conducted On Western Sugar's Boiler And Pulp Dryer
Stacks Located In Billings, Montana, American Environmental Testing Company, Inc.,
January 1990.
13. Report On Compliance Testing Performed At Western Sugar Company Pulp Dryer, Scottsbluff, NE,
Clean Air Engineering, Palatine, IL, January 12, 1990.
3/97 Food And Agricultural Industry ' 9.10.1.2-11
-------
14. Emission Measurement Test Report Of C.E. Boilers, Union Boilers, And Pulp Dryers-Permit.
Compliance For SO2, Participate, And PM-10 With Back-Half Emissions-Holly Sugar
Corporation, Montana Division, The Emission Measurement Group, Inc., Englewood, CO,
November 16, 1993.
15. .Report To Great Lakes Sugar Company On Stack Particulate Samples Collected On The Pulp Drier
At Fremont, Ohio, Affiliated Environmental Services, Inc., Sandusky, OH, December 8, 1992.
16. Results Of The February 22-24, 1994, Air Emission Compliance Testing Of Process Sources At The
American Crystal Sugar East Grand Forks Plant, Interpoll Laboratories, Inc., Circle Pines, MN,
March 21, 1994.
17. Results Of The January 28-31, 1992, Particulate Emission Tests, South Pulp Dryer-American
Crystal Sugar Company, Moorehead, Minnesota, Bay West, Inc., St. Paul, MN, March 26, 1992.
18. Results Of A Source Emission Compliance Test On The Sugar Cooler Stack At American Crystal
Sugar Company, Crookston, Minnesota, March 11, 1993, Twin City Testing Corporation,
St. Paul. MN, April 16, 1993.
19. Results Of The November 9-11, 1993, Air Emission Testing Of Process Sources At The American
Crystal Sugar East Grand Forks Plant, Interpoll Laboratories, Inc., Circle Pines, MN,
December 3, 1993.
20. Results Of The November 14 And 15, 1990, State Particulate Emission Compliance Test On The
Sugar Cooler And Sugar GranulatorAt The ACS Moorehead Plant, Interpoll Laboratories, Inc.,
Circle Pines, MN, December 11, 1990.
21. Unit Nos. 1 And 2 Pulp Dryer Stacks Emission Testing Results For The February 22-26, 1993,
Testing Of Particulate Conducted At The American Crystal Sugar Company, Crookston,
Minnesota, Bay West, Inc., St. Paul, MN, April 15/1993.
22. Particulate Emission Study For Michigan Sugar Company, Caro, Michigan, Swanson
Environmental, Inc., Farmington Hills, MI, December 14, 1989.
23. Particulate Emission Study For Michigan Sugar Company, Carrollton, Michigan, Swanson
Environmental, Inc., Farmington Hills, MI, November 1989.
24. Particulate Emission Study-Michigan Sugar Company, Croswell, Michigan, Swanson
Environmental, Inc., Farmington Hills, MI, November 19, 1990.
25. Emissions Survey Conducted At Western Sugar Company, Scottsbluff, Nebraska, American
Environmental Testing, Inc. Spanish Fork, UT, January 10, 1995.
9.10.1.2-12
EMISSION FACTORS
3/97
-------
9.12.3 Distilled Spirits
9.12.3.1 General1'2
The distilled spirits industry includes the production of whisky, gin, vodka, rum, and brandy. The
production of brandy is discussed in AP-42 Section 9.12.2, "Wines and Brandy". Distilled spirits
production also may include the production of secondary products such as distillers dried grains used for
livestock feed and other feed/food components.
Distilled spirits, including grain spirits and neutral spirits, are produced throughout the United
States.1 The Bureau of Alcohol, Tobacco, and Firearms (BATF) has established "standards of identity"
for distilled spirits products.2
.9.12.3.2 Process Description3-4 /
Distilled spirits can be produced by a variety of processes. Typically, in whisky production,
grains are mashed and fermented to produce an alcohol/water solution, that is distilled to concentrate the
alcohol. For whiskies, the distilled product is aged to provide flavor, color, and aroma. This discussion
will be limited to the production of Bourbon whisky. Figure 9.12.3-1 is a simple diagram of a typical
whisky production process. Emission data are available only for the fermentation and aging steps of
whisky production.
9.12.3.2.1 Grain Handling And Preparation -
Distilleries utilize premium cereal grains, such as hybrid corn, rye, barley, and wheat, to produce
the various types of whisky and other distilled spirits. Grain is received at a distillery from a grain-
handling facility and is prepared for fermentation by milling or by malting (soaking the grains to induce
germination). All U.S. distillers purchase malted grain instead of performing the malting process onsite.
9.12.3.2.2 Grain Mashing -
Mashing consists of cooking the grain to solubilize the starch from the kernels and to convert the
soluble starch to grain sugars with barley malt and/or enzymes. Small quantities of malted barley are
sometimes added prior to grain cooking. The mash then passes through a noncontact cooler to cool the
converted mash prior to entering the fermenter.
9.12.3.2.3 Fermentation-
The converted mash enters the fermenter and is inoculated with yeast. The fermentation process,
which usually lasts 3 to 5 days for whisky, uses yeast to convert the grain sugars into ethanol and carbon
dioxide. Congeners are flavor compounds which are produced during fermentation as well as during the
barrel aging process. The final fermented grain alcohol mixture, called "beer", is transferred to a "beer
well" for holding. From the beer well, the beer passes through a preheater, where it is warmed by the
alcohol vapors leaving the still, and then to the distillation unit. The beer still vapors condensed in the
preheater generally are returned to the beer still as reflux.
3/97 Food And Agricultural Industry ' 9.12.3-1
-------
Grain Receiving
(Matted Grains)
PM Emissions
PM Emissions
OPTIONAL PROCESS
Barley Malt
or Enzymes
PM Emissions
_J
Grain Mashing
(Conversion of Starches to Sugars)
(3-02-010-13)
Yeast-
-VOC Emissions3
Fermentation
(Conversion of Sugars to Alcohol)
(342-010-14)
Backset SHIage
Ethanol and CCg Emissions'3
Backset Stillage
Whole Stillage
Distillation
(342-010-15)
Dryer House Operations
pstillers Dried Grains)
(3-02-010-02)
• PM Emissions3
VOC Emissions; Noncondensed Off-Gases3
Intermediate Storage
Warehousing/Aging
(3-02-010-17)
Ethanol Emissions (Breathing)
Ethanol Emissions.
Intermediate Storage
Ethanol Emissions (Breathing)
Blending/Bottling
(342-010-18)
Ethanol Emissions
* Processes require heat. Emissions generated (e.g., CO, CC>2, NOX, S02, PM, and VOCs) will depend on the source of fuel.
' Other compounds can be generated in trace quantities during fermentation including ethyl acetate, fusel oil, furfural,
acetaldehyde, sulfur dioxide, and hydrogen sulfide. Acetaldehyde is a hazardous air pollutant (HAP).
Figure 9.12.3-1. Whisky production process.
(Source Classification Codes in parentheses).
9.12.3-2
EMISSION FACTORS
3/97
-------
9.12.3.2.4 Distillation -
The distillation process separates and concentrates the alcohol from the fermented grain mash.
Whisky stills are usually made of copper, especially in the rectifying section, although stainless steel may
be used in some stills. Following distillation, the distilled alcohol spirits are pumped to stainless steel tanks
and diluted with demineralized water to the desired alcohol concentration prior to filling into oak barrels
and aging. Tennessee whisky utilizes a different process from Bourbon in that the distillate is passed
through sugar maple charcoal in mellowing vats prior to dilution with demineralized water.
9.12.3.2.5 Grain And Liquid Stillage ("Dryer House Operations") -
In most distilleries, after the removal of alcohol, still bottoms (called whole stillage), are pumped
from the distillation column to a dryer house. Whole stillage may be sold, land applied (with permitting),
sold as liquid feed, or processed and dried to produce distillers dried grains (DDG) and other secondary
products. Solids in the whole stillage are separated using centrifuges or screens; the liquid portion (thin
stillage) may be used as a backset or concentrated by vacuum evaporation. The concentrated liquid may,.
be recombined with the solids or dried. Drying is typically accomplished using either steam-heated or
flash dryers.
9.12.3.2.6 Warehousing/Aging -
Aging practices differ from distiller to distiller, and even for the same distiller. Variations in the
aging process are integral to producing the characteristic taste of a particular brand of distilled spirit. The
aging process, which typically ranges from 4 to 8 years or more, consists of storing the new whisky
distillate in oak barrels to encourage chemical reactions and extractions between the whisky and the wood.
The constituents of the barrel produce the whisky's characteristic color and distinctive flavor and aroma.
White oak is used because it is one of the few woods that holds liquids while allowing breathing (gas
exchange) through the wood. Federal law requires all Bourbon whisky to be aged in charred new white
oak barrels.
The oak barrels and the barrel environment are key to producing distilled spirits of desired quality.
The new whisky distillate undergoes many types of physical and chemical changes during the aging process
that removes the harshness of the new distillate. As whisky ages, it extracts and reacts with constituents in
the wood of the barrel, producing certain trace substances, called congeners, which give whisky its
distinctive color, taste, and aroma.
Barrel environment is extremely critical in whisky aging and varies considerably by distillery,
warehouse, and even location in the warehouse. Ambient atmospheric conditions, such as seasonal and
diurnal variations in temperature and humidity, have a great affect on the aging process, causing changes
in the equilibrium rate of extraction, rate of transfer by diffusion, and rate of reaction. As a result,
distillers may expose the barrels to atmospheric conditions during certain months, promoting maturation
through the selective opening of windows and doors and by other means.
Distillers often utilize various warehouse designs, including single- or multistory buildings
constructed of metal, wood, brick, or masonry. Warehouses generally rely upon natural ambient
temperature and humidity changes to drive the aging process. In a few warehouses, temperature is
adjusted during the winter. However, whisky warehouses do not have the capability to control humidity,
which varies with natural climate conditions.
9.12.3.2,7 Blending/Bottling-
Once the whisky has completed its desired aging period, it is transferred from the barrels into
tanks and reduced in proof to the desired final alcohol concentration by adding demineralized water.
3/97 Food And Agricultural Industry 9.12.3-3
-------
Following a filtration process that renders it free of any solids, the whisky is pumped to a tank in the
bottling house, bottled, and readied for shipment to the distributors.
9.12.3.3 Emissions And Controls3'6
9.12.3.3.1 Emissions -
The principal emissions from whisky production are volatile organic compounds (VOCs),
principally ethanol, and occur primarily during the aging/warehousing stage. In addition to ethanol, other
volatile compounds, including acetaldehyde (a HAP), ethyl acetate, glycerol, fusel oil, .and furfural, may
be produced in trace amounts during aging. A comparatively small source of ethanol emissions may result
from the fermentation stage. Smaller quantities of ethyl acetate, isobutyl alcohol, and isoamyl alcohol are
generated as well; carbon dioxide is also produced during fermentation. Particulate matter (PM) emissions
are generated by the grain receiving, handling, drying, and cleaning processes and are discussed in more
detail in AP-42 Section 9.9.1, Grain Elevators and Processes. Other emissions, including SO2, CO2, CO,
NOX, and PM may be generated by fuel combustion from power production facilities located at most
distilled spirits plant.
Ethanol and water vapor emissions result from the breathing phenomenon of the oak barrels during
the aging process. This phenomenon of wood acting as a semipermeable membrane is complex and not
well understood. The emissions from evaporation from the barrel during aging are not constant. During
the first 6 to 18 months, the evaporation rate from a new barrel is low because the wood must become
saturated (known as "soakage") before evaporation occurs. After saturation, the evaporation rate is
greatest, but then decreases as evaporation lowers the liquid level in the barrel. The lower liquid level
decreases the surface area of the liquid in contact with the wood and thus reduces the surface area subject
to evaporation. The rate of extraction of wood constituents, transfer, and reaction depend upon ambient
conditions, such as temperature and humidity, and the concentrations of the various whisky constituents.
Higher temperatures increase the rate of extraction, transfer by diffusion, and reaction. Diurnal and
seasonal temperature changes cause convection currents in the liquid. The rate of diffusion will depend
upon the differences in concentrations of constituents in the wood, liquid, and air blanketing the barrel.
The rates of reaction will increase or decrease with the concentration of constituents. The equilibrium
concentrations of the various whisky components depend upon the humidity and air flow around the barrel.
Minor emissions are generated when the whisky is drained from the barrels for blending and
bottling. Residual whisky remains in the used barrels both as a surface film ("heel") and within the wood
("soakage"). For economic reasons, many distillers attempt to recover as much residual whisky as
possible by methods such as rinsing the barrel with water and vacuuming. Generally, barrels are refilled
and reentered into the aging process for other distilled spirits at the particular distiller or sealed with a
closure (bung) and shipped offsite for reuse with other distilled spirits. Emissions may also be generated
during blending and bottle filling, but no data are available.
9.12.3.3.2 Controls-
With the exception of devices for controlling PM emissions, there are very few emission controls
at distilleries. Grain handling and processing emissions are controlled through the use of cyclones,
baghouses, and other PM control devices (see AP-42 Section 9.9.1). There are currently no current
control technologies for VOC emissions from fermenters because the significant amount of grain solids
that would be carried out of the fermenters by air entrainment could quickly render systems, such as
carbon adsorption, inoperable. Add-on air pollution control devices for whisky aging warehouses are not
used because of potential adverse impact on product quality. Distillers ensure that barrel construction is of
high quality to minimize leakage, thus reducing ethanol emissions. Ethanol recovery would require the use
9.12.3-4 EMISSION FACTORS 3/97
-------
of a collection system to capture gaseous emissions in the warehouse and to process the gases through a
recovery system prior to venting them to the atmosphere.
9.12.3.3.3 Emission Factors -
Table 9.12.3-1 provides uncontrolled emission factors for emissions of VOCs from fermentation
vats and for emissions of ethanol from aging due to evaporation. Because ethanol is the principal VOC
emission from aging, the ethanol emissions factors are reasonable estimates of VOC emissions for these
processes. Emission factors for grain receiving, handling, and cleaning may be found in
AP-42 Section 9.9.1, Grain Elevators and Processes. Emission factors are unavailable for grain mashing,
distillation, blending/bottling, and spent grain drying. An emission factor for carbon dioxide from
fermentation vats is also unavailable, although carbon dioxide and ethanol are theoretically generated in
equal molecular quantities during the fermentation process.
Table 9.12.3-1. EMISSION FACTORS FOR DISTILLED SPIRITS3
EMISSION FACTOR RATING: E
Sourceb
Grain mashing
(SCC 3-02-010-13).
Fermentation vats
(SCC 3-02-010-14)
Distillation
(SCC 3-02-010-15)
Aging
(SCC 3-02-010-17)
Evaporation loss
Blending/bottling
(SCC 3-02-010-18)
Dryer house operations
(SCC 3-02-010-02)
Ethanol
NA
14.2C
ND
6.9e
ND
ND
Ethyl acetate
NA
0.046C
ND
ND
ND
ND
Isoamyl
Alcohol
NA
0.013C
ND
ND
ND -.-
ND
Isobutyl
Alcohol
NA
0.004C
ND
ND
ND
ND
a Factors represent uncontrolled emissions. SCC = Source Classification Code. ND = no data
available. To convert from Ib to kg, divide by 2.2. NA = not applicable.
b Emission factors for grain receiving, handling, and cleaning processes are available in
AP-42 Section 9.9.1, Grain Elevators and Processes.
c Reference 5 (paper). In units of pounds per 1,000 bushels of grain input.
d Evaporation losses during whisky aging do not include losses due to soakage.
e References 6-7. In units of Ib/bbl/yr; barrels have a capacity of approximately 53 gallons.
Recognizing that aging practices may differ from distiller to distiller, and even for different
products of the same distiller, a method may be used to estimate total ethanol emissions from barrels
during aging. An ethanol emission factor for aging (total loss emission factor) can be calculated based on
annual emissions per barrel in proof gallons (PG). The term "proof gallon" refers to a U.S. gallon of
proof spirits, or the alcoholic equivalent thereof, containing 50 percent of ethyl alcohol (ethanol) by
volume. This calculation method is derived from the gauging of product and measures the difference in
the amount of product when the barrel was filled and when the barrel was emptied. Fugitive evaporative
3/97
Food And Agricultural Industry
9.12.3-5
-------
emissions, however, are not the sole difference between these two amounts. During the aging period,
product soaks into the barrel, test samples are drawn, and other losses (e. g., spillage, leakage) may occur.
Estimates of ethanol loss due to evaporation during aging based only on the gauging of product will
produce an overestimate unless soakage and sampling losses (very small losses) are subtracted. The
emission factor for evaporation loss in Table 9.12.3-1 represents an overestimate because only data for
soakage losses could be calculated; data for other losses were not available.
References for Section 9.12.3
1. Bureau Of Alcohol, Tobacco, And Firearms (BATF), "Monthly Statistical Release-Distilled
Spirits", Department Of The Treasury, Washington, DC, January 1995 through December 1995.
2. "Standards Of Identity For Distilled Spirits", 27 CFR Part 1, Subpart C, Office Of The Federal
Register, National Archives And Records Administration, Washington, D.C., April 1, 1996.
3. Bujake, J. E., "Beverage Spirits, Distilled", Kirk-Othmer Encyclopedia Of Chemical Technology,
4th. Ed., Volume No. 4, John Wiley & Sons, Inc., 1992. . .
4. Cost And Engineering Study Control Of Volatile Organic Emissions From Whiskey Warehousing,
EPA-450/2-78-013, Emissions Standards Division, Chemical and Petroleum Branch^ Office Of
Air Quality Planning And Standards, U. S. Environmental Protection Agency, Research Triangle
Park, NC, April 1978.
5. Carter, R. V., and B. Linsky, "Gaseous Emissions From Whiskey Fermentation Units",
Atmospheric Environment, 8:57-62, January 1974; also a preliminary paper of the same title by
these authors (undated).
6. Written communication from R. J. Garcia, Seagrams Americas, Louisville, KY, to T. Lapp,
Midwest Research Institute, Gary, NC, March 3, 1997. RTGs versus age for 1993 standards.
7. Written communication from L. J. Omlie, Distilled Spirits Council Of The United States,
Washington, D.C., to T. Lapp, Midwest Research Institute, Gary, NC, February 6, 1997.
Ethanol emissions data from Jim Beam Brands Co.
9.12.3-6 EMISSION FACTORS 3/97
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9.15 Leather Tanning
9.15.1 General1-4
Leather tanning is the process of converting raw hides or skins into leather. Hides and skins have the
ability to absorb tannic acid and other chemical substances that prevent them from decaying, make them
resistant to wetting, and keep them supple and durable. The surface of hides and skins contains the hair and
oil glands and is known as the grain side. The flesh side of the hide or skin is much thicker and softer. The
three types of hides and skins most often used in leather manufacture are from cattle, sheep, and pigs.
Tanning is essentially the reaction of collagen fibers in the hide with tannins, chromium, alum, or
other chemical agents. The most common tanning agents used in the U. S. are trivalent chromium and
vegetable tannins extracted from specific tree barks. Alum, syntans (man-made chemicals), formaldehyde,
glutaraldehyde, and heavy oils are other tanning agents.
There are approximately 111 leather tanning facilities in the United States. However, not every
facility may perform the entire tanning or finishing process. Leather tanning and finishing facilities are most
prevalent in the northeast and midwest states; Pennsylvania, Massachusetts, New York, and Wisconsin
account for almost half of the facilities. The number of tanneries in the United States has significantly
decreased in the last 40 years due to the development of synthetic substitutes for leather, increased leather
imports, and environmental regulation.
9.15.2 Process Description1 -2-5'6
Although the title of this section is "Leather Tanning", the entire leathermaking process is considered
here, not just the actual tanning step. "Leather tanning" is a general term for the numerous processing steps
involved in converting animal hides or skins into finished leather. Production of leather by both vegetable
tanning and chrome tanning is described below. Chrome tanning accounts for approximately 90 percent of U.
S. tanning production. Figure 9.15-1 presents a general flow diagram for the leather tanning and finishing
process. Trimming, soaking, fleshing, and unhairing, the first steps of the process, are referred to as the
beamhouse operations. Bating, pickling, tanning, wringing, and splitting are referred to as tanyard processes.
Finishing processes include conditioning, staking, dry milling, buffing, spray finishing, and plating.
9.15.2.1 Vegetable Tanning-
Heavy leathers and sole leathers are produced by the vegetable tanning process, the oldest of any
process in use in the leather tanning industry. The hides are first trimmed and soaked to remove salt and
other solids and to restore moisture lost during curing. Following the soaking, the hides are fleshed to remove
the excess tissue, to impart uniform thickness, and to remove muscles or fat adhering to the hide. Hides are
then dehaired to ensure that the grain is clean and the hair follicles are free of hair roots. Liming is the most
common method of hair removal, but thermal, oxidative, and chemical methods also exist The normal
procedure for liming is to use a series of pits or drums containing lime liquors (calcium hydroxide) and
sharpening agents. Following liming, the hides are dehaired by scraping or by machine. Deliming is then
performed to make the skins receptive to the vegetable tanning. Bating, an enzymatic action for the removal
of unwanted hide components after liming, is performed to impart softness, stretch, and flexibility to the
leather. Bating and deliming are usually performed together by placing the hides in an aqueous solution of an
ammonium salt and proteolytic
6/97 Food And Agricultural Industry 9.15-1
-------
BEAMHOUSE
TANYARD
1
Chrome Tanning
'
.
RETAN. COLOR,
FATLIQUOR
FINISHING
r ,
Receiving and Storing Hides]
i
Trimming
Y"
Soaking and Washing
Y
Fleshing
__. -,.
Unhairing
_
_j.
Bating
*
. Pickling
+
..
'
'
'
+
Wringing/Siding
i
Spitting
Grain portion!
Shaving
'
Fles
1
»
Retanning
t
Bleaching and Coloring
*
Fatliquoring
(Chrome tanning)
*
Setting Out
*
Drying
\
Conditioning
+
Staking, Dry Milling
*
Buffing
1
Finishing and Plating
-
»• Sulfides, NH3
i •
Vegetable Tanning
4i portion
*- To split tannery, retanning
to> DM
•
"
"
*• PM
9.15-2
Figure 9.15-1. General flow diagram for leather tanning and finishing process.
EMISSION FACTORS
6/97
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enzymes at 27° to 32°C(80° to 90°F). Pickling may also be performed by treating the hide with abrine
solution and sulfuric acid to adjust the acidity for preservation or tanning.
In the vegetable tanning process, the concentration of the tanning materials starts out low and is
gradually increased as the tannage proceeds. It usually takes 3 weeks for the tanning material to penetrate to
the center of the hide. The skins or hides are then wrung and may be cropped or split; heavy hides may be
retanned and scrubbed. For sole leather, the hides are commonly dipped in vats or drums containing sodium
bicarbonate or sulfuric acid for bleaching and removal of surface tannins. Materials such as lignosulfate,
com sugar, oils, and specialty chemicals may be added to the leather. The leather is then set out to smooth
and dry and may then undergo further finishing steps. However, a high percentage of vegetable-tanned
leathers do not undergo retanning, coloring, fatliquoring, or finishing.
Leather may be dried by any of five common methods. Air drying is the simplest method. The
leather is hung or placed on racks and dried by the natural circulation of air around it. A toggling unit
consists of a number of screens placed in a dryer that has controlled temperature and humidity. In a pasting
unit, leathers are pasted on large sheets of plate glass, porcelain, or metal and sent through a tunnel dryer with
several controlled temperature and humidity zones. In vacuum drying, the leather is spread out, grain down,
on a smooth surface to which heat is applied. A vacuum hood is placed over the surface, and a vacuum is
applied to aid in drying the leather. High-frequency drying involves the use of a high frequency
electromagnetic field to dry the leather.
9.15.2.2 Chrome Tanning- " ' . "
Chrome-tanned learner tends to be softer and more pliable than vegetable-tanned leather, has higher
thermal stability, is very stable in water, and takes less time to produce than vegetable-tanned leather.
Almost all leather made from lighter-weight cattle hides and from the skin of sheep, lambs, goats, and pigs is
chrome tanned. The first steps of the process (soaking, fleshing, liming/dehairing, deliming, bating, and
pickling) and the drying/finishing steps are essentially the same as in vegetable tanning. However, in chrome
tanning, the additional processes of retanning, dyeing, and fatliquoring are usually performed to produce
usable leathers and a preliminary degreasing step may be necessary when using animal skins, such as
sheepskin.
Chrome tanning in the United States is performed using a one-bath process that is based on the
reaction between the hide and a trivalent chromium salt, usually a basic chromium sulfate. In the typical one-
bath process, the hides are in a pickled state at a pH of 3 or lower, the chrome tanning materials are
introduced, and the pH is raised. Following tanning, the chrome tanned leather is piled down, wrung, and
graded for the thickness and quality, split into flesh and grain layers, and shaved to the desired thickness. The
grain leathers from the shaving machine are.then separated for retanning, dyeing, and fatliquoring. Leather
that is not subject to scuffs and scratches can be dyed on the surface only! For other types of leather (i. e.,
shoe leather) the dye must penetrate further into the leather. Typical dyestuffs are aniline-based compounds
that combine with the skin to form an insoluble compound.
Fatliquoring is the process of introducing oil into the skin before the leather is dried to replace the
natural oils lost in beamhouse and tanyard processes. Fatliquoring is usually performed in a drum using an
oil emulsion at temperatures of about 60° to 66 °C (140° to 150 °F) for 30 to 40 minutes. After fatliquoring,
the leather is wrung, set out, dried, and finished. The finishing process refers to all the steps that are carried
out after drying.
6/97 Food And Agricultural Industry 9.15-3
-------
9.15.2.3 Leather Finishing
Leathers may be finished in a variety of ways: buffed with fine abrasives to produce a suede finish;
waxed, shellacked, or treated with pigments, dyes, and resins to achieve a smooth, polished surface and the
desired color; or lacquered with urethane for a glossy patent leather. Water-based or solvent-based finishes
may also be applied to the leather. Plating is then used to smooth the surface of the coating materials and
bond them to the grain. Hides may also be embossed.
9.15.3 Emissions and Controls2-4-6
There are several potential sources of air emissions in the leather tanning and finishing industry.
Emissions of VOC may occur during finishing processes, if organic solvents are used, and during other
processes, such as fatliquoring and drying. If organic degreasing solvents are used during soaking in suede
leather manufacture, these VOC may also evaporate to the atmosphere. Many tanneries are implementing
water-based coatings to reduce VOC emissions. Control devices, such as thermal oxidizers, are used less
frequently to reduce VOC emissions. Ammonia emissions may occur during some of the wet processing
steps, such as deliming and unhairing, or during drying if ammonia is used to aid dye penetration during
coloring. Emissions of sulfides may occur dmingliming/unhairing and subsequent processes. Also, alkaline
sulfides in tannery wastewater can be converted to hydrogen sulfide if the pH is less than 8.0, resulting in
release of this gas. Particulate emissions may occur during shaving, drying, and buffing; they are controlled
by dust collectors or scrubbers.
Chromium emissions may occur from chromate reduction, handling of basic chromic sulfate powder,
and from the buffing process. No air emissions of chromium occur during soaking or drying. At plants that
purchase chromic sulfate in powder form, dust containing bivalent chromium may be emitted during storage,
handling, and mixing of the dry chromic sulfate. The buffing operation also releases particulates, which may
contain chromium. Leather tanning facilities, however, have not been viewed as sources of chromium
emissions by the States in which they are located.
References for Section 9.15
1. K. Bienkiewicz, Physical Chemistry Of Leathermaking, Krieger Publishing Co., Malabar, FL, 1983.
2. Development Document For Effluent Limitations Guidelines And Standards For The Leather
Tanning And Finishing Point Source Category, EPA-440/1-82-016, U. S. Environmental Protection
Agency, Research Triangle Park, NC, November, 1982.
3. 1992 Census Of Manufactures, U. S. Department of Commerce, Bureau of Census, Washington,
DC, April 1995.
4. Telecon, A. Marshall, Midwest Research Institute, with F. Rutland, Environmental Consultant,
Leather Industries of America, August 7,1996.
5. 1996 Membership Directory, Leather Industries of America Inc.
6. M. T. Roberts and D. Etherington, Bookbinding And The Conservation Of Books, A Dictionary Of
Descriptive Terminology.
7. T. C. Thorstensen, Practical Leather Technology, 4th Ed., Krieger Publishing Co., Malabar, FL,
1993.
9.15-4 EMISSION FACTORS 6/97
-------
8. Locating And Estimating Air Emissions From Sources Of Chromium, EPA-450/4-84-007g, U. S.
Environmental Protection Agency, Research Triangle Park, NC, July 1984.
6/97 Food And Agricultural Industry 9.15-5
-------
-------
11.3 Brick And Structural Clay Product Manufacturing
11.3.1 General1'2
The brick and structural clay products industry is made up primarily of facilities that manufacture
structural brick from clay, shale, or a combination of the two. These facilities are classified under standard
industrial classification (SIC) code 3251, brick and structural clay tile. Facilities that manufacture structural
clay products, such as clay pipe, adobe brick, chimney pipe, flue liners, drain tiles, roofing tiles, and sewer
tiles are classified under SIC code 3259, structural clay products, not elsewhere classified.
11.3.2 Process Description3"6
The manufacture of brick and structural clay products involves mining, grinding, screening and
blending of the raw materials followed by forming, cutting or shaping, drying, firing, cooling, storage, and
shipping of the final product. A typical brick manufacturing process is shown in Figure 11.3-1.
The raw materials used in the manufacture of brick and structural clay products include surface clays
and shales, which are mined in open pits. The moisture content of the raw materials ranges from a low of
about 3 percent at some plants to a high of about 15 percent at other plants. Some facilities have onsite
mining operations, while others bring in raw material by truck or rail. The raw material is typically loaded by
truck or front-end loader into a primary crusher for initial size reduction. The material is then conveyed to a
' grinding room,; which houses several grinding mills and banks of screens that produce a fine material that is
suitable for forming brick or other products. Types of grinding mills typically used include dry pan grinders,
roller mills, and hammermills. From the grinding room, the material is conveyed to storage silos or piles,
which typically are enclosed. The material is then either conveyed to the mill room for brick forming or
conveyed to a storage area.
Most brick are formed by the stiff mud extrusion process, although brick are also formed using the
soft mud and dry press processes (there may be no plants in the U.S. currently using the dry press process).
A typical stiff mud extrusion line begins with a pug mill, which mixes the ground material with water and
discharges the mixture into a vacuum chamber. Some facilities mix additives such as barium carbonate,
which prevents sulfates from rising to the surface of the brick, with the raw material prior to extrusion. The
moisture content of the material entering the vacuum chamber is typically between 14 and 18 percent. The
vacuum chamber removes air from the material, which is then continuously augered or extruded through dies.
The resulting continuous "column" is lubricated with oil or other lubricant to reduce friction during extrusion.
If specified, various surface treatments, such as manganese dioxide, iron oxide, and iron chromite can be
applied at this point. These treatments are used to add color or texture to the product. A wire-cutting
machine is used to cut the column into individual bricks, and then the bricks are mechanically or hand set onto
kiln cars. All structural tile and most brick are formed by this process. Prior to stacking, some facilities
mechanically process the unfired bricks to create rounded imperfect edges that give the appearance of older
worn brick.
The soft mud process is usually used with clay that is too wet for stiff mud extrusion. In a pug mill,
the clay is mixed with water to a moisture content of 15 to 28 percent, and the bricks are formed in molds and
are dried before being mechanically stacked onto kiln cars. In the dry press process, clay is mixed with a
small amount of water and formed in steel molds by applying pressure of 500 to 1,500 pounds per square
inch (3.43 to 10.28 megapascals).
8/97 Mineral Products 11.3-1
-------
11.3-2
EMISSION FACTORS
8/97
-------
Following forming and stacking, the brick-laden kiln cars enter a predryer or a holding area and are
then loaded into the dryer. Dryers typically are heated to about 400°F (204 °C) using waste heat from the
cooling zone of the kiln. However, some plants heat dryers with gas or other fuels. Dryers may be in-line or
totally separate from the kiln. From the dryer, the bricks enter the kiln. The most common type of kiln used
for firing brick is the tunnel kiln, although some facilities operate downdraft periodic kilns or other types of
kilns. A typical tunnel kiln ranges from about 340 feet (ft) (104 meters [m]) to 500 ft (152 m) in length and
includes a preheat zone, a firing zone, and a cooling zone. The firing zone typically is maintained at a
maximum temperature of about 2000°F (1090°C). During firing, small amounts of excess fuel are
sometimes introduced to the kiln atmosphere, creating a reducing atmosphere that adds color to the surface of
the bricks. This process is called flashing. After firing, the bricks enter the cooling zone, where they are
cooled to near ambient temperatures before leaving the tunnel kiln. The bricks are then stored and shipped.
A periodic kiln is a permanent brick structure with a number of fireholes through which fuel enters
the furnace. Hot gases from the fuel are first drawn up over the bricks, then down through them by
underground flues, and then out of the kiln to the stack.
In all kilns, firing takes place in six steps: evaporation of free water, dehydration, oxidation,
vitrification, flashing, and cooling. Natural gas is the fuel most commonly used for firing, followed by coal
and sawdust. Some plants have fuel oil available as a backup fuel. Most natural gas-fired plants that have a
backup fuel use vaporized propane as the backup fuel. For most types of brick, the entire drying, firing, and
cooling process takes between 20 and 50 hours.
Flashing is used to impart color to bricks by adding uncombusted fuel (other materials such as zinc,
used tires, or used motor oil are also reportedly used) to the kiln to create a reducing atmosphere. Typically,
flashing takes place in a "flashing zone" that follows the firing zone, and the bricks are rapidly cooled
following flashing. In tunnel kilns, the uncombusted fuel or other material typically is drawn into the firing
zone of the kiln and is burned.
11.3.3 Emissions And Controls3'7-11'22'24'29-30
Emissions from brick manufacturing facilities include particulate matter (PM), PM less than or equal
to 10 microns in aerodynamic diameter (PM-10), PM less than or equal to 2.5 microns in aerodynamic
diameter (PM-2.5) sulfur dioxide (SO2), sulfur trioxide (SO3), nitrogen oxides (NOX), carbon monoxide
(CO), carbon dioxide (CO2), metals, total organic compounds (TOC) (including methane, ethane, volatile
organic compounds [VOC], and some hazardous air pollutants [HAP]), hydrochloric acid (HC1), and fluoride
compounds. Factors that may affect emissions include raw material composition and moisture content, kiln
fuel type, kiln operating parameters, and plant design. The pollutants emitted from the manufacture of other
structural clay products are expected to be similar to the pollutants emitted from brick manufacturing,
although emissions from the manufacture of glazed products may differ significantly.
The primary sources of PM, PM-10, and PM-2.5 emissions are the raw material grinding and
screening operations and the kilns. Other sources of PM emissions include sawdust dryers used by plants
with sawdust-fired kilns, coal crushing systems used by plants with coal-fired kilns, and fugitive dust sources
such as paved roads, unpaved roads, and storage piles.
Combustion products, including SO2, NOX, CO, and CO2, are emitted from fuel combustion in brick
kilns and some brick dryers. Brick dryers that are heated with waste heat from the kiln cooling zone are not
usually a source of combustion products because kilns are designed to prevent combustion gases from
entering the cooling zone. Some brick dryers have supplemental gas burners that produce small amounts of
NOX, CO, and CO2 emissions. These emissions are sensitive to the condition of the burners. The primary
8/97 Mineral Products 11.3-3
-------
source of S O2 emissions from most brick kilns is the raw material, which sometimes contain sulfur
compounds. Some facilities use raw material with a high sulfur content, and have higher SO2 emissions than
facilities that use low-sulfur raw material. In addition, some facilities use additives that contain sulfates, and
these additives may contribute to SO2 emissions. Data are available that indicate that sulfur contents of
surface soils are highly variable, and it is likely that sulfur contents of brick raw materials are also highly
variable.
Organic compounds, including methane, ethane, VOC, and some HAP, are emitted from both brick
dryers and kilns. These compounds also are emitted from sawdust dryers used by facilities that fire sawdust
as the primary kiln fuel. Organic compound emissions from brick dryers may include contributions from the
following sources: (1) petroleum-based or other products in those plants that use petroleum-based or other
lubricants in extrusion, (2) light hydrocarbons within the raw material that vaporize at the temperatures
encountered in the dryer, and (3) incomplete fuel combustion in dryers that use supplemental burners in
addition to waste heat from the kiln cooling zone. Organic compound emissions from kilns are the result of
volatilization of organic matter contained in the raw material and kiln fuel.
Hydrogen fluoride (HF) and other fluoride compounds are emitted from kilns as a result of the
release of the fluorine compounds contained in the raw material. Fluorine typically is present in brick raw
materials in the range of 0.01 to 0.06 percent. As the green bricks reach temperatures of 930° to 1110°F,
(500° to 600 °C), the fluorine in the raw material forms HF and other fluorine compounds. Much of the
fluorine is released as HF. Because fluorine content in clays and shales is highly variable, emissions of HF
and other fluoride compounds vary considerably depending on the raw material used.
A variety of control systems may be used to reduce PM emissions from brick manufacturing
operations. Grinding and screening operations are sometimes controlled by fabric filtration systems, although
many facilities process raw material with a relatively high moisture content (greater than 10 percent) and do
not use add-on control systems. Most tunnel kilns are not equipped with control devices, although fabric
filters or wet scrubbers are sometimes used for PM removal. Particulate matter emissions from fugitive
sources such as paved roads, unpaved roads, and storage piles can be controlled using wet suppression
techniques.
Gaseous emissions from brick dryers and kilns typically are not controlled using add-on control
devices. However, dry scrubbers that use limestone as a sorption medium may be used to control HF
emissions; control efficiencies of 95 percent or higher have been reported at one plant operating this type of
scrubber. Also, wet scrubbers are used at one facility. These scrubbers, which use a soda ash and water
solution as the scrubbing liquid, provide effective control of HF and SO2 emissions. Test data show that the
only high-efficiency packed tower wet scrubber operating in the U.S. (at brick plants) achieves control
efficiencies greater than 99 percent for SO2 and total fluorides. A unique "medium-efficiency" wet scrubber
operating at the same plant has demonstrated an 82 percent SO2 control efficiency.
Process controls are also an effective means of controlling kiln emissions. For example, facilities
with coal-fired kilns typically use a low-sulfur, low-ash coal to minimize SO2 and PM emissions. In addition,
research is being performed on the use of additives (such as lime) to reduce HF and SO2 emissions.
Table 11.3-1 presents emission factors for filterable PM, filterable PM-10, condensible inorganic
PM, and condensible organic PM emissions from brick and structural clay product manufacturing operations.
Two emission factors for uncontrolled grinding and screening operations are presented; one for operations
processing relatively dry material (about 4 percent moisture) and the other for operations processing wet
material (about 13 percent moisture). Table 11.3-2 presents total PM, total PM-10, and total PM-2.5
emission factors for brick and structural clay product manufacturing. Table 11.3-3 presents emission factors
11.3-4 EMISSION FACTORS " 8/97
-------
for SO2, SO3, NOX, CO, and CO2 emissions from brick dryers, kilns (fired with natural gas, coal, and
sawdust), and from a combined source-sawdust-fired kiln and sawdust dryer. To estimate emissions of NOX,
and CO from fuel oil-fired kilns, refer to the AP-42 section addressing oil combustion. Table 11,3-4 presents
emission factors for HF, total fluorides, and HC1 emissions from brick kilns and from a combined source--
sawdust-fired kilns and sawdust drying. Table 11.3-5 presents emission factors for TOC as propane,
methane, and VOC from brick dryers, kilns, and from a combined source—sawdust-fired kilns and sawdust
drying. Tables 11.3-6 and 11.3-7 present emission factors for speciated organic compounds and metals,
respectively. Table 11.3-8 presents particle size distribution data for sawdust- and coal-fired kilns. Although
many of the emission factors presented in the tables are assigned lower ratings than emission factors in
previous editions of AP-42, the new factors are based on higher quality data than the old factors.
8/97 Mineral Products 11.3-5
-------
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a
•*u
o
1 Primary crusher with fab
(SCC 3-05-003-40)
*
$
£
f
Q
§
H
1
o'
W
v\
s
o'
£
I .
Grinding and screening o
(SCC 3-05-003-02)
processing wet materia
..
Zt
„
.
**
33
P P
s §
W W
d 8
°' §
« w
VI i
oo o
0
.f 1
,,.
s ti 1 — 1
^* -^ o
<; "^H ob
^ o o'
s s s
POP
2 z S
w -g w
vo e
§ °
J3 W °
p ^ !L
g O CO
~ do
|
Extrusion line with fabric
(SCC 3-05-003-42)
Brick dryer
(SCC 3-05-003-50, -51
Natural gas-fired kiln
(SCC 3-05-003-11)
P
'* — i
o'
P
So
o.
P
oo
o
O
c-
o'
•^
w
Coal-fired kiln
(SCC 3-05-003-13)
uncontrolled
P P
i — i < — i
0 O
p p
00 00
o' o'
^ °
Q 'O
O
^ °
Q cs
^ 0
W P
fc*r
0 ro
o o
with fabric filter
Sawdust-fired kiln
(SCC 3-05-003-10)
„
o
o
W
co
o
o'
<
p
2
M
d
W
CO
^
'o
•o
i
1
I Sawdust-fired kiln and se
•
g
s
p
g
g
§
w
o
T-H
§>
O
f-~
M1
(SCC 3-05-003-61)
Natural gas-fired kiln firi
tilez
8
0
9
CO
8
r° t!
H o
t
s
&•
3
II
•log
l^-s
11.3-6
EMISSION FACTORS
8/97
-------
8/97
Mineral Products
11.3.-7
-------
Table 11.3-2. EMISSION FACTORS FOR TOTAL PM, TOTAL PM-10, AND TOTAL PM-2.5
FROM BRICK MANUFACTURING OPERATIONS*
Source
Primary crusher with fabric filter
(SCO 3-05-003-40)
Grinding and screening operations
(SCC 3-05-003-02)
processing dry material0
processing wet material"1
with fabric filter6
Extrusion line with fabric filter
(SCC 3-05-003-42)
Natural gas-fired kiln
(SCC 3-05-003-11)
Coal-fired kiln
(SCC 3-05-003-1 3)
uncontrolled
with fabric filter
Sawdust-fired kiln
(SCC 3-05-003-10)
Sawdust-fired kiln and sawdust dryer8
(scc s-os-oos-en
Total PMb
PM
ND
8.5
0.025
0.0062
ND
0.96
1.8
0.63
0.93
1.4
EMISSION
FACTOR
RATING
NA
E
E
E
NA
D
B
E
D
E
PM-10
0.00059
0.53
0.0023
0.0032
0.0036
0.87
1.4
ND
0.85
0.31
EMISSION
FACTOR
RATING
E
E
E
E
E
D
C
NA
D
E
PM-2.5
ND
ND
ND
ND
ND
ND
0.87
ND
0.75
ND
EMISSION
FACTOR
RATING
NA
NA
NA
NA
NA
NA
D
NA
D
NA
a Emission factor units are Ib of pollutant per ton of fired bricks produced unless noted. Factors represent
uncontrolled emissions unless noted. SCC = Source Classification Code. ND = nodata. NA = not
applicable. To convert from Ib/ton to kg/Mg, multiply by 0.5.
Total PM emission factors are the sum of filterable PM and condensible inorganic and organic PM '
emission factors from Table 11.3-1. Total PM-10 emission factors are the sum of filterable PM-10 and
condensible inorganic and organic PM emission factors from Table 11.3-1. Total PM-2.5 emission factors
are the sum of filterable PM-2.5 and condensible inorganic and organic PM emission factors from Table
11.3-1.
0 Emission factor units are Ib of pollutant per ton of raw material processed. Grinding and screening
operations are typically housed in large buildings that can be fully or partially enclosed. Factor is based on
measurements at the inlet to a fabric filter and does not take into account the effect of the building
enclosure. Based on a raw material moisture content of 4 percent.
Emission factor units are Ib of pollutant per ton of raw material processed. Based on a raw material
moisture content of 13 percent Grinding and screening operations are typically housed in large buildings
that can be fully or partially enclosed.
c Emission factor units are Ib of pollutant per ton of raw material processed. Grinding and screening
operations are typically housed in large buildings that can be fully or partially enclosed.
This emission factor is not applicable to typical extrusion lines. Extrusion line with several conveyor drop
points processing material with a 5-9 percent moisture content
8 Sawdust dryer heated with the exhaust stream from a sawdust-fired kiln.
11.3-8
EMISSION FACTORS
8/97
-------
a
g
O
w
0
o
1
CJ
1
^J
2
£3
S
PQ
O
i
H
0
^
0
HH
oo
00
H- (
W
f*"^
i-H
JD
'S
H
111
8"
CO H H
CO o H
|2i2
o
0
*P40
l§§
|^«
X
y
§gg
8gH
1^
d1
CO
§f*0
CO H R
CO o H
|^^
^
O
CO
1
o
CO
W PQ pq
<« e - . s
\?H O O
. t~ o o
P3 O O
o *"* ^
WO O
•^ .^ ~ ' '
o °°. "^
§ ®
PQ PQ
S S
o o
0 0
0 0
C-4 O4
i— i i — i
O O
"CS "CS
co co
o o
O
0
CO
Q
"o
.00
o
Q
^
«n
o
Q
1
Q
X
vq
i — r
w
., .
CO
O
> ;• * *.tt «
J3 '
^ 0 "^
' ^ ° Q
O/) -^
n Wbin "S
fcnWO wO OTtGO ' — !
s, § co a co a --3 co 2
S|8 p 148 1
•g a?s 1 Q ia ss |
TO & Jz;
0 O
_ *&>
51, •*
°. ' . 0
o
^^
S"
with medium-efficien
wet scrubber*1
with high-efficiency
packed-bed scrubber1
p
*•
Q
^
* — '
Coal-fired kiln
(SCC 3-05-003- 13)
^
0
O
CO
^o
o
Sawdust-fired kiln
(SCC 3-05-003-10)
S S 3
Ugf
* -^r & §
s1^«
^11^
'G 5 to wT
•§ ^ * -S
CO JJ1 _ >^ > »^
a s ^>-x
^^'S"?
ra "« -g .b
S 'g § '
2 ° So "3
S |>g S
o S " i-i -
W ?H W O
s 8 § ^
S a '^ IQ
s fx.a .1
•g ^
w 6fl
*
III
If!;
) co (t~l o
s s _:
8/97
Mineral Products
11.3.-9
-------
4-S
a
o
•§
Bri
Re
11.3-10
EMISSION FACTORS
8/97
-------
Table 11.3-4. EMISSION FACTORS FOR HYDROGEN FLUORIDE, TOTAL FLUORIDES, AND
HYDROGEN CHLORIDE FROM BRICK MANUFACTURING OPERATIONS4
Source
Sawdust- or natural gas-fired tunnel kiln
(SCC 3-05-003-10,-! 1)
uncontrolled
with dry scrubber11
with medium-efficiency wet scrubber1
with high-efficiency packed-bed
scrubber1'
Coal-fired tunnel kiln"1
(SCC 3-05-003-13)
Sawdust-fired kiln and sawdust dryer"
(SCC 3-05-003-61)
HFb
0.37e
ND
ND
ND
0.17
0.18
EMISSION
FACTOR
RATING
C
NA
'. NA
NA
D
E
Total
fluorides0
0.59f
0.028
0.18
0.0013
ND
ND
EMISSION
FACTOR
RATING
E
C
C
C
NA
NA
HCld
0.178
ND
ND
ND
ND
ND
EMISSION
FACTOR
RATING
D
NA
NA
NA
NA
NA
a Emission factor units are Ib of pollutant per ton of fired product. Factors represent uncontrolled emissions
unless noted. To convert from Ib/ton to kg/Mg, multiply by 0.5. SCC = Source Classification Code. ND
= no data. NA = not applicable.
b Hydrogen fluoride measured using an EPA Method 26A or equivalent sampling train.
0 Total fluorides measured using an EPA Method 13B or equivalent sampling train.
d Hydrogen chloride measured using an EPA Method 26A or equivalent sampling train.
6 References 8,11,26-27,32,34. Factor includes data from kilns firing structural clay tile. Data from kiliis
firing natural gas and sawdust are averaged together because fuel type (except for coal) does not appear to
affect HF emissions. However, the raw material fluoride content does effect HF emissions. A mass
balance on fluoride will provide a better estimate of emissions for individual facilities. Assuming that all
of the fluorine in the raw material is released as HF, each Ib of fluorine will result in 1.05 Ib of HF .
emissions.
f Reference 26. Factor is 1.6 times the HF factor.
g References 8,26.
h References 22,33-34. Kiln firing material with a high fluorine content. Dry scrubber using limestone as a
sorption medium.
J Reference 29. Medium-efficiency wet scrubber using a soda-ash/water solution (maintained at pH 7) as
the scrubbing liquid. The design of this scrubber is not typical. Kiln firing material with a high fluorine
content.
k Reference 30. High-efficiency packed bed scrubber with soda-ash/water solution circulated through the
packing section. Kiln firing material with a high fluorine content (uncontrolled emission factor of
2. lib/ton).
m References 9,26.
n Reference 11. Sawdust dryer heated with the exhaust stream from a sawdust-fired kiln.
8/97
Mineral Products
11.3-11
-------
Table 11.3-5. EMISSION FACTORS FOR TOC, METHANE, AND VOC
FROM BRICK MANUFACTURING OPERATIONS'1
Source
Brick dryer11
(SCC 3-05-003-50)
Brick dryer w/supplemental gas burner
(SCC 3-05-003-51)
Brick kiln*
(SCC3-05-003-10,-11,-13)
Sawdust-fired kiln and sawdust dryer"
(SCC 3-05-003-61)
TOCb
0.05e
0.148
0.062k
0.18
EMISSION
FACTOR
RATING
E
E
C
E
Methane
0.02f
O.llh
0.037m
ND
EMISSION
FACTOR
RATING
E
E
E ,
NA
VOCC
0.03
0.03
0.024
0.18
EMISSION
FACTOR
RATING
E
E
D
E
a Emission factor units are Ib of pollutant per ton of fired product. Factors represent uncontrolled emissions
unless noted. To convert from Ib/ton to kg/Mg, multiply by 0.5. SCC = Source Classification Code. ND
= no data. ND = not applicable.
b Total organic compounds reported "as propane"; measured using EPA Method 25A, unless noted.
c VOC as propane; calculated as the difference in the TOC and methane emission factors for this source. If
no methane factor is available, VOC emissions are estimated using the TOC emission factor. In addition,
emissions of the non-reactive compounds shown in Table 11.3-6 (brick kiln = 0.00094 Ib/ton) are
subtracted from the TOC factors to calculate VOC.
d Brick dryer heated with waste heat from the kiln cooling zone.
c References 9-10.
f Reference 9. Methane value includes methane and ethane emissions. Most of these emissions are believed
to be methane.
s References 8,37.
h Factor is estimated by assuming that VOC emissions from dryers with and without supplemental burners
are equal. The VOC factor is subtracted from the TOC factor to estimate methane emissions.
J Includes natural gas-, coal-, and sawdust-fired tunnel kilns.
k References 8-11,25,32,36-37. Data from kilns firing natural gas, coal, and sawdust are averaged together
because the data indicate that the fuel type does not effect TOC emissions.
m References 8-9,25. Data from kilns firing natural gas, coal, and sawdust are averaged together because the
data indicate that the fuel type does not effect methane emissions.
n Reference 11. Sawdust dryer heated with the exhaust stream from a sawdust-fired kiln.
11.3-12
EMISSION FACTORS
8/97
-------
Table 11.3-6. EMISSION FACTORS FOR ORGANIC POLLUTANT EMISSIONS FROM
BRICK MANUFACTURING OPERATIONS3
EMISSION FACTOR RATING: E
Source
Coal-fired kiln
(SCO 3-05-003-13)
Pollutant
CASRN
75-34-3
71-55-6
106-46-7
78-93-3
591-78-6
91-57-6
95-48-7
67-64-1
71-43-2
65-85-0
1 17-81-7
74-83-9
85-68-7
75-15-0
56-23-5
108-90-7
75-00-3
67-66-3
74-87-3
132-64-9
84-66-2
131-11-3
100-41-4
78-59-1
1330-20-7
75-09-2
91-20-3
95-47-6
108-95-2
100-42-5
127-18-4
71-55-6
108-88-3
108-05-4
75-69-4
Name
1 ,1-dichloroethane
l,l>l-trichloroethaneb*
1 ,4-dichlorobenzene
2-butanone
2-hexanoneb
2-methylnaphthalene
2-methylphenolb
Acetone*
Benzene
Benzoic acid
Bis(2-ethylhexy)phthalate
Bromomethane
Butylbenzylphthalate .
Carbon disulfide
Carbon tetrachlorideb
Chlorobenzene
Chloroethane
Chloroformb
Chloromethane
Dibenzofuran0
Di-n-octylphthalate
Diethylphthalate
Dimethylphthalateb
Ethylbenzene
[sophorone
M-/p-xylene
VIethylene chloride*
STaphthalene
O-xylene
Phenol
Styreneb
Tetrachloroethaneb
Trichloroethaneb*
Toluene
Vinyl acetateb
Trichlorofluoromethane*
Emission Factor,
Ib/ton
S.OxlO'6
BDL (1.7xlO's)
.3.2xlO'6
2.5X10"4
BDL (9.4xlQ-7)
IJxlO-6
BDL(2.2xlO'6)
6.8x10-*
2.9xlO'4
2.5xlO'4
7.3xW5
2.4X10'5
1.2xW6
2.3xlO'6
BDL (l.OxlO"7)
2.1X10'5
l.lxlO'5
BDL(1.0xlO-7)
l.lxlO-4
3.6xlO'7
1.2xlO'5
1.4X10'6
BDL (7.8X10'7)
2.1xlO'5
S.OxlO'5
1.3X10"4
S.OxlO'7
6.9xlO"6
4.7xlO'5
3.5xlQ-5
BDL (l.OxlO'7)
BDL (l.OxlO'7)
BDL(1.0xlO-7)
2.5X10"4
BDL(1.0xlO'7)
1.4xlO'5
Ref.No.
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
8/97
Mineral Products
11.3-13
-------
Table 11.3-6 (cont).
Source
Natural gas-fired kiln
(SCC3-05-003-11)
Sawdust-fired kiln
(SCO 3-05-003-10)
Pollutant
CASRN
71-55-6
106-46-7
91-57-6
78-93-3
591-78-6
67-64-1
71-43-2
117-81-7
85-68-7
75-15-0
7782-50-5
75-00-3
74-87-3
84-74-2
84-66-2
100-41-4
1330-20-7
74-88-4
91-20-3
95-47-6
108-95-2
100-42-5
127-18-4
108-88-3
71-55-6
78-93-3
591-78-6
95-48-7
67-64-1
107-13-1
71-43-2
117-81-7
74-83-9
75-15-0
56-23-5
67-66-3
74-87-3
84-74-2
132-64-9
Name
1,1,1-Trichloroethane*
1 ,4-dichlorobenzene
2-methylnaphthalene
2-butanone
2-Hexanone
Acetone*
Benzene
Bis(2-ethylhexy)phthalate
Butylbenzylphthalate
Carbon disulfide
Chlorine
Chloroethane
Chloromethane
Di-n-butylphthalate
Diethylphthalate
Ethylbenzene
M-/p-Xylene
lodomethane
Naphthalene
o-Xylene
Phenol
Styrene
Tetrachloroethene
Toluene
l,l,l-trichloroethaneb*
2-butanoneb
2-hexanoneb
2-methylphenolb
Acetone*
Aciylonitrile0
Benzene
Bis(2-ethylhexy)phthalate
Bromomethane
Carbon disulfide
Carbon tetrachlorideb
Chloroform15
Chloromethane
Di-n-butylphthalatec
Dibenzofuran
Emission Factor,
Ib/ton
4.7xlO'6
4.8xlO"5
5.7xlO'5
0.00022
8.5xlO'5
0.0017
0.0029
0.0020
l.SxlO'5
4.3xlO-s
0.0013
0.00057
0.00067
0.00014
0.00024
4.4xW5
6.7xlO'5
9.3xlO'5
6.5xlO"5
5.8xlO"5
8.6xW5
2.0xlO's
2.8X10"6
0.00016
BDL(3.0xlO'7)
BDL (6.6XW6)
BDL(3.0xlO-7)
BDL(2.0xlO'9)
3.9XW4
1.5xlO'5
5.2X10"4
2.9xlO'5
S.OxlO"5
1.6X10"5
BDL (S.OxW7)
BDL (3.0xW7)
6.8X10"4
6.1xlO'6
l.SxlO'5
Ref.No.
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11.3-14
EMISSION FACTORS
8/97
-------
Table 11.3-6 (cont.).
Source
Sawdust-fired kiln
(SCC 3-05-003- 10)
Sawdust-fired kiln
and sawdust dryer
(SCC 3-05-003-61)
Pollutant
CASRN
84-74-2
100-41-4
74-88-4
1330-20-7
75-09-2
91-20-3
95-47-6
108-95-2
100-42-5
127-18-4
108-88-3
71-55-6
75-69-4
108-05-4
71-55-6
78-93-3
591-78-6
95-48-7
67-64-1
107-13-1
71-43-2
117-81-7
74-83-9
75-15-0
56-23-5
67-66-3
74-87-3
84-74-2
132-64-9
131-11-3
100-41-4
74-88-4
1330-20-7
75-09-2
91-20-3
95-47-6
108-95-2
100-42-5
127-18-4
Name
Dimethylphthalate0
Ethylbenzene
lodomethane
M-/p-xylene
Methylene chloride*
Naphthalene0
O-xylene°
Phenol
Styreneb
Tetrachloroethaneb
Toluene
Trichloroethaneb*
Trichlorofluoromethane*
Vinyl acetate*3
l,l,l-trichloroethaneb*
2-butanone
2-hexanoneb
2-methylphenolb
Acetone*
Acrylonitrile
Benzene
Bis(2-ethylhexy)phthalate
Bromomethane
Carbon disulfide
Carbon tetrachlorideb
Chloroformb
Chloromethane
Di-n-burylphthalate
Dibenzofuranb
Dimethylphthalateb
Ethylbenzene
[odomethane
M-/p-xylene
Vfethylene chloride*
Naphthalene15
O-xylene
Phenol
Styrene
Tetrachloroethaneb
Emission Factor,
Ib/ton
l.OxlO'5
8.5xlO'6
2.0X10"4
2.9xlO'5
7.5xlO"6
3.4X10"4
3.8xlO'6
7.2xlO'5
BDL (4.4xlO'7)
BDL (S.OxlO'7)
l.lxlQ-4
BDL (S.OxlO"7)
5.8xW6
BDL (3.0xlO"7)
BDL (5.2xlO"7)
2.2XW4
BDL (3.8xW7)
BDL (2.4xlQ-9)
0.0010
1.9X10'5
5.6x10-*
1.4xlO'4
4.4xlO'5
LSxlO'5
BDL (3.8xlO'7)
BDL (3.8xW7)
0.0014
1.6xlO'5
BDL(2.4xlO'9)
BDL (2.4xlO'9)
l.OxlO'5
2.4x10-*
2.9xlO'5
6.2xlO'5
BDL (2.4X10'9)
7.3xlO'6
l.OxlQ-4
BDL (4.2xlO-6)
BDL (3.8xlO~7)
Ref. No.
11
11
11
11,
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
8/97
Mineral Products
11.3-15
-------
Table 11.3-6 (cont).
Source
Sawdust-fired kiln and
sawdust dryer
(SCC 3-05-003-61)
Pollutant
CASRN
108-88-3
71-55-6
75-69-4
108-05-4
Name
Toluene
Trichloroethaneb*
Trichlorofluoromethane*
Vinyl acetate
Emission Factor,
Ib/ton
4.3xlO'4
BDL (3.8xlO"7)
l.OxlO'6
1.9xlO'7
Ref. No.
11 .
11
11
11
a Emission factor units are Ib of pollutant per ton of fired bricks produced. To convert from Ib/ton to
kg/Mg, multiply by 0.5. CASRN = Chemical Abstracts Service Registry Number. * = Non-reactive
compound as designated in 40 CFR. 51.100(s), July 1, 1995. BDL = concentration was below the method
detection limit
b The emission factor for this pollutant is shown in parentheses and is based on the detection limit.
0 Emissions were below the detection limit during two of three test runs. Emission factor is estimated as the
average of the single measured quantity and one-half of the detection limit for the two nondetect runs.
d These emission factors are based on data from an atypical facility.
c Sawdust dryer heated with the exhaust stream from a sawdust-fired kiln.
11.3-16
EMISSION FACTORS
8/97
-------
Table 11.3-7. EMISSION FACTORS FOR METALS EMISSIONS
FROM BRICK MANUFACTURING OPERATIONS*
Source
Kilnb (SCC 3-05-003-10,-! 1,-13)
Coal-fired kiln (SCC 3-05-003-13)
Natural gas-fired kiln (SCC 3-05-003-11)
Sawdust-fired kiln (SCC 3-05-003-10)
Sawdust-fired kiln and sawdust dryerd
(SCC 3-05-003-61)
Pollutant
Antimony
Cadmium
Chromium
Cobalt
Lead
Nickel .
Selenium
Arsenic
Beryllium
Manganese
Mercury
Phosphorus
Arsenic
Beryllium
Manganese
Mercury
Arsenic
Beryllium
Manganese
Mercury .
Phosphorus
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Lead
Manganese
Mercury
Nickel
Phosphorus
Selenium
Emission Factor,
Ib/ton
2.7xlO-5
i.SxlO'5
S.lxlO-5
2.1X10-6
1.5x10-4
7.2xlO-5
2.3x10-4
1.3x10-4
1.6xlO-5
2.9x10-4
9.6xlO'5
9.8x10-4
3.1xlO-5
4.2xlO'7
2.9x10-4
7.5X10-6
3.1xlO'5
4.2xlO-7
0.013C
7.5xlO-6
9.8x10-4
2.8xlO'6
2.1xlO-5
3.1xlO-7
2.2xlO-5
4.8xlO'5
1.2x10-4
4.8x10-4
LlxlO'5
3.4xlO'5
5.5x10-4
4.7xlO'5
EMISSION
FACTOR
RATING
D
D
D
E
D
D
D
E
E
D
E
E
D
D
D
D
D
D
E
D
E
E
E
E
E
E
E
E .
E
E
E
E
Reference
Nos.
8-9,11,25
8-9,11,25
9,11,25
25
8-9,11,25
9,11,25
8-9,11,25
9
9
8-9,25
9
9,11 •-
8,11,25
8,11,25
8-9,25
11,25
8,11,25
8,11,25
11
11,25
9,11
11
11
11
11
11
11
11
11
11
11
11
a Emission factor units are Ib of pollutant per ton of fired brick produced. Emission factors for individual
facilities will vary based on the metal content of the raw material, metallic colorants used on the face of the
bricks, metallic additives mixed into the bodies of the bricks, and the metal content of the fuels used for
firing the kilns.
b Coal-, natural gas-, or sawdust-fired tunnel kiln.
c The facility uses a manganese surface treatment on the bricks. The manganese emission factor for coal-
and natural gas-fired kilns is a better estimate for sawdust-fired kilns firing bricks that do not have a
manganese surface treatment Conversely, this emission factor should be used to estimate manganese
emissions from coal- or natural gas-fired kilns firing a product with manganese surface treatment
d Sawdust dryer heated with the exhaust stream from a sawdust-fired kiln.
8/97
Mineral Products
11.3-17
-------
Table 11.3.8. AVERAGE PARTICLE SIZE DISTRIBUTION
FORFILTERABLE PMEMISSIONS FROM KILNSa
Source
Sawdust-fired kiln
Coal-fired kiln
Aerodynamic Diameter,
microns
10b
2.5
1
10b
2.5 ;
1
Percent of Filterable PM
Emissions Less Than or Equal
to Stated Particle Size
75
; 48
44
63
23
9.8
Reference No.
11,20
11,20
11,20
9,21
21
21
0 Particle size distribution based on cascade impactor tests unless noted.
Based on cascade impactor particle size distribution and a comparison of PM-10 (measured using EPA
Method 201A) and filterable PM (measured using EPA Method 5) emissions.
REFERENCES FOR SECTION 11.3 .
1. 1992 Census Of Manufactures, Cement And Structural Clay Products, U. S. Department Of
Commerce, Washington, D.C., 1995.
2. Telephone communication between B. Shrager, Midwest Research Institute, Gary, NC, and
N. Cooney, Brick Institute Of America, Reston, VA, October, 20,1994.
3. Compilation Of Air Pollutant Emission Factors, U. S. Environmental Protection Agency, Research
Triangle Park, NC, October 1986.
4. Written communication from J. Dowdle, Pine Hall Brick Co., Inc., Madison, NC, to R. Myers, U. S.
Environmental Protection Agency, Research Triangle Park, NC, September 1992.
5. Written communication from B. Shrager, Midwest Research Institute, Gary, NC, to R. Myers, U. S.
Environmental Protection Agency, Research Triangle Park, NC, April 1993.
6. Written communication from B. Shrager, Midwest Research Institute, Cary, NC, to R. Myers, U. S.
Environmental Protection Agency, Research Triangle Park, NC, September 1993.
7. D. A. Brosnan, "Monitoring For Hydrogen Fluoride Emissions", Ceramic Industry, July 1994.
8. Emission Testing At A Structural Brick Manufacturing Plant-Final Emission Test Report For
Testing At Belden Brick Company, Plant 6, Sugarcreek, OH, U. S. Environmental Protection
Agency, Research Triangle Park, NC, February 1995.
9. Final Test Report For U. S. EPA Test Program Conducted At General Shale Brick Plant, Johnson
City, TN, U. S. Environmental Protection Agency, Research Triangle Park, NC, December 1993.
10. Flue Gas Characterization Studies Conducted On The SOB Kiln And Dryer Stacks In Atlanta, GA
For General Shale Corporation, Guardian Systems, Inc., Leeds, AL, March 1993.
11.3-18
EMISSION FACTORS
8/97
-------
11. Final Test Report For U. S. EPA TestProgram Conducted At Pine Hall Brick Plant, Madison, NC,
U. S. Environmental Protection Agency, Research Triangle Park, NC, August 1993.
12. Source Emission TestAtBelden Brick, Inc., Sugarcreek, OH, No. 1 Kiln, Plants, CSA Company,
Alliance, OH, March 3, 1992.
13. Mass Emission Tests Conducted On The Tunnel Kiln #6B And #28 In Marion, VA, For General
Shale Products Corporation, Guardian Systems, Inc., Leeds, AL, October 1990.
14. Mass Emission Tests Conducted On The Tunnel Kiln #21 In Glascow, VA, For General Shale
Products Corporation, Guardian Systems, Inc., Leeds, AL, October 16,1990.
15. Source Emission TestAtBelden Brick, Inc., Sugarcreek, OH, No. 1 Kiln, Plants, CSA Company,
Alliance, OH, July 21,1989.
16. Sulfur Dioxide Emission Tests Conducted On The #20 Tunnel Kiln In Mooresville, IN, For
General Shale Products Corporation, Guardian Systems, Inc., Leeds, AL, December 2,1986.
17. Mass Emission Tests Conducted On The #7B Tunnel Kiln In Knoxville, TN, For General Shale
Products Corporation, Guardian Systems, Inc., Leeds, AL, April 22, 1986.
18. Mass Emission Tests Conducted On Plant #15 In Kingsport, TN, For General Shale Products
Corporation, Guardian Systems, Inc., Leeds, AL, October 11,1983.
19. Particulate Emission Tests For General Shale Products Corporation, Kingsport, TN, Tunnel Kiln
TK-29 And Coal Crusher, Guardian Systems, Inc., Leeds, AL, July 21,1982.
20. Building Brick And Structural Clay Wood Fired Brick Kiln, Emission Test Report, Chatham Brick
And Tile Company, Gulf, NC, EMB Report 80-BRK-5, U. S. Environmental Protection Agency,
Research Triangle Park, NC, October 1980.
21. Building Brick And Structural Clay Industry, Emission TestReport, Lee Brick And Tile Company,
Sanford, NC, EMB Report 80-BRK-l, U. S. Environmental Protection Agency, Research Triangle
Park, NC, April 1980.
22. Exhaust Emission Sampling, Acme Brick Company, Sealy, TX, Armstrong Environmental Inc.,
Dallas, TX, June 21, 1991.
23. Stationary Source Sampling Report: Chatham Brick And Tile Company, Sanford, NC, Kiln No. 2
Particulate Emissions Compliance Testing, Entropy Environmentalists, Inc., Research Triangle
Park, NC, July 1979.
24. D. Brosnan, "Technology And Regulatory Consequences Of Fluorine Emissions In Ceramic
Manufacturing", American Ceramic Industry Bulletin, 71 (12), pp 1798-1802, The American
Ceramic Society, Westerville, OH, December 1992.
8/97 Mineral Products 11.3-19
-------
25. Stationary Source Sampling Report Reference No. 14448, Triangle Brick, Merry Oaks, North
Carolina, Emissions Testing For: Carbon Monoxide, Condensible Particulate, Metals, Methane,
Nitrogen Oxides, Particulate, Particulate < 10 Microns, Sulfur Dioxide, Total Hydrocarbons,
Entropy, Inc., Research Triangle Park, NC, October, 1995.
26. BIA HF Research Program Stack Testing Results (and Individual Stack Test Data Sheets), Center,
for Engineering Ceramic Manufacturing, Clemson University, Anderson, SC, November, 1995.
27. Source Emission Tests At Stark Ceramics, Inc., East Canton, OH, No. 3 Kiln Stack, CSA
Company, Alliance, OH, September 16,1993.
28. Crescent Brick Stack Test-No. 2 Tunnel Kiln, CSA Company, Alliance, OH, February 29,1988.
29. Emissions Survey Conducted At Interstate Brick Company, Located In West Jordan, Utah,
American Environmental Testing, Inc., Spanish Fork, UT, December 22,1994.
30. Emissions Survey For SO2, NO^ CO, HF, And PM-10 Emissions Conducted On Interstate Brick
Company's Kiln No. 3 Scrubber, Located In West Jordan, Utah, American Environmental Testing,
Inc., Spanish Fork, UT, November 30,1995.
31. Stationary Source Sampling Report For Isenhour Brick Company, Salisbury, North Carolina, No.
6 Kiln Exhausts 1 And 2, Sawdust Dryer Exhaust, Trigon Engineering Consultants, Inc., Charlotte,
NC, October 1995.
32. Particulate, Fluoride, And CEMEmissions Testing On The #1 And #2 Kiln Exhausts, Boral
Bricks, Inc., Smyrna, Georgia, Analytical Testing Consultants, Inc., Roswell, GA, September 26,
1996.
33. Source Emissions Survey Of Boral Bricks, Inc., Absorber Stack (EPN-K), Henderson, Texas, TACB
Permit 21012, METCO Environmental, Addison, TX, June 1995.
34. Source Emissions Survey Of Boral Bricks, Inc., Absorber Stack (EPN-K) And Absorber Inlet Duct,
Henderson, Texas, METCO Environmental, Addison, TX, February 1996.
35. Stationary Source Sampling Report For Statesville Brick Company, Statesville, NC, Kiln Exhaust,
Sawdust Dryer Exhaust, Trigon Engineering Consultants, Inc., Charlotte, NC, November 1994.
36. Source Emissions Testing, Marseilles Brick, Marseilles, Illinois, Fugro Midwest, Inc., St. Ann,
MO, October 13,1994.
37. Source Emissions Testing, Marseilles Brick, Marseilles, Illinois, Fugro Midwest, hie., St. Ann,
MO, July 1,1994.
38. Emission Factor Documentation forAP-42 Section 11.3, Brick and Structural Clay Product
Manufacturing, Final Report, Midwest Research Institute, Gary, NC, August 1997.
11.3-20 EMISSION FACTORS 8/97
-------
11.14 Frit Manufacturing
11.14.1 Process Description1"6
Frit is a homogeneous melted mixture of inorganic materials that is used in enameling iron and steel
and in glazing porcelain and pottery. Frit renders soluble and hazardous compounds inert by combining them
with silica and other oxides. Frit also is used in bonding grinding wheels, to lower vitrification temperatures,
and as a lubricant in steel casting and metal extrusion. The six digit Source Classification Code (SCC) for
frit manufacturing is 3-05-013.
Frit is prepared by fusing a variety of minerals in a furnace and then rapidly quenching the molten
material. The constituents of the feed material depend on whether the frit is to be used as a ground coat or as
a cover coat. For cover coats, the primary constituents of the raw material charge include silica, fluorspar,
soda ash, borax, feldspar, zircon, aluminum oxide, lithium carbonate, magnesium carbonate, and titanium
oxide. The constituents of the charge for a ground coat include the same compounds plus smaller amounts of
metal oxides such as cobalt oxide, nickel oxide, copper oxide, and manganese oxide.
To begin the process, raw materials are shipped to the manufacturing facility by truck or rail and are
stored in bins. Next, the raw materials are carefully weighed in .the correct proportions. The raw batch then
is dry mixed and transferred to a hopper prior to being fed into the smelting furnace. Although pot furnaces,
hearth furnaces, and rotary furnaces have been used to produce frit in batch operations, most frit is now
produced in continuous smelting furnaces. Depending on the application, frit smelting furnaces operate at
temperatures of 930° to 1480°C (1700° to 2700°F). If a continuous furnace is used, the mixed charge is fed
by screw conveyor directly into the furnace. Continuous furnaces operate at temperatures of 1090° to
1430°C (2000° to 2600°F). When smelting is complete, the molten material is passed between water-cooled
metal rollers that limit the thickness of the material, and then it is quenched with a water spray that shatters
the material into small glass particles called frit
After quenching, the frit is milled by either wet or dry grinding. If the latter, the frit is dried before
grinding. Frit produced in continuous furnaces generally can be ground without drying, and it is sometimes
packaged for shipping without further processing. Wet milling of frit is no longer common. However, if the
frit is wet-milled, it can be charged directly to the grinding mill without drying. Rotary dryers are the devices
most commonly used for drying frit. Drying tables and stationary dryers also have been used. After drying,
magnetic separation may be used to remove iron-bearing material. The frit is finely ground in a ball mill, into
which clays and other electrolytes may be added, and then the product is screened and stored. The frit
product then is transported to on-site ceramic manufacturing processes or is prepared for shipping. In recent
years, the electrostatic deposition spray method has become the preferred method of applying frit glaze to
surfaces. Frit that is to be applied in that manner is mixed during the grinding step with an organic silicon
encapsulating agent, rather than with clay and electrolytes. Figure 11.14-1 presents a process flow diagram
for frit manufacturing. .
11.14.2 Emissions And Controls1-7-10 .
Significant emissions of particulate matter (PM) and PM less than 10 micrometers (PM-10) are
created by the frit smelting operation in the form of dust and fumes. These emissions consist primarily of
condensed metallic oxide fumes that have volatilized from the molten charge. The emissions also contain
mineral dust and sometimes hydrogen fluoride. Emissions from furnaces also include products of
combustion, such as carbon monoxide (CO), carbon dioxide (CO^, and nitrogen oxides (NOJ. Sulfur oxides
(SOJ also may be emitted, but they generally are absorbed by the molten material to form an
6/97 Mineral Products Industry 11.14-1.
-------
1 r
CLAYS. OTHER ... __
ELECTROLYTES.^ J«jjfIQ
(GRINDING)
l r
RAW MATERIALS
STORAGE
1
'
WEIGHING
(3-05-013-02)
l
r
MIXING
(3-05-013-03)
i
r
FURNACE
CHARGING
(3-05-013-04)
\
r
SMELTING
FURNACE
(34)5-013-04)
\
1
QUENCHING
(3-05-013-10)
i
> PACKAGING ^
l
l r
r
r
TO CERAMIC
MANUFACTURING
PROCESS
SHIPPING
xjy
A
.-^ (?) PM EMISSIONS
A (I) GASEOUS EMISSIONS
J
9
A
©CD
A A
A A
* 0©
DRYING ft
1
npVMiitiMf* ^ CLAYS AND OTHER
^,M^,U? "* ELECTROLYTES OR
(GRINDING) ENCAPSULATING AGENT
(3-05-013-15)
* ©
SCREENING ^
(3-05-013-16)
V
Figure 11.14-1 Process flow diagram for frit manufacturing.
(Source Classification Code in parentheses)
11.14-2
EMISSION FACTORS
6/97
-------
immiscible sulphate that is eliminated in the quenching operation. Particulate matter also is emitted from
drying, grinding, and materials handling and transfer operations
Emissions from the furnace can be minimized by careful control of the rate and duration of raw
material heating, to prevent volatilization of the more fusible charge materials. Emissions from rotary
furnaces also can be reduced with careful control of the rotation speed, to prevent excessive dust carryover.
Ventun scrubbers and fabric filters are the devices most commonly used to control emissions from frit
smelting furnaces, and fabric filters are commonly used to control emissions from grinding operations. No
information is available on the type of emission controls used on quenching, drying, and materials handling
and transfer operations.
Table 11.14-1 presents emission factors for filterable PM, GO, NOB and COj, emissions from frit
manufacturing. Table 11,14-2 presents emission factors for other pollutant emissions from frit
manufacturing.
11.14.3 Updates Since the Fifth Edition
The Fifth Edition was released in January 1995. A complete revision of this section was completed
on 11/95. The emission factor for NOx for Smelting Furnace was revised on 6/97 based upon a review of the
production information that was provided by the manufacturing facility.
Table 11.14-1. EMISSION FACTORS FOR FRIT MANUFACTURING2
EMISSION FACTOR RATING: E
Source
Smelting furnace
(SCC 3-05-013-05,06)
Smelting furnace with venturi scrubber
(SCC 3-05-0 13-05,06)
Smelting furnace with fabric filter
(SCC 3-05-0 13-05,-06)
Filterable PMb
16°
1.8f
0.020d
CO
4.8°
g
s
NOX
16d
s
s
C02
l,300e
g
g
" Factors represent uncontrolled emissions unless otherwise noted. Emission factor units are Ib/ton of
feed material. ND = nodata. SCC = Source Classification Code. To convert from Ib/ton to kg/Mg,
multiply by 0.5. . •
b Filterable PM is that PM collected on or prior to the filter of an EPA Method 5 (or equivalent)
sampling train.
c Reference 1.
d Reference 10. . . : . .
'Reference 7-10.
f References 7-9. EMISSION FACTOR RATING: D
g See factor for uncontrolled emissions.
6/97
Mineral Products Industry
11.14-3
-------
Table 11.14-2. EMISSION FACTORS FOR FRIT MANUFACTURING-
FLUORIDES AND METALS3
EMISSION FACTOR RATING: E
Smelting furnace with fabric filter
(SCC 3-05-0 13-05,-06)
Pollutant
fluorides
barium
chromium
cobalt
copper
lead
manganese
nickel
zinc
Emission factor, Ib/ton
0.88
2.8 x 10-5
1.4 x 10-5
4.3xlO-6
1.9 xIO'5
9.6 x 10-6
1.4 xlfr5
'1.6x10*
1.2 x 10-4
"Reference 10. Factor units are Ib/ton of material feed.
SCC = Source Classification Code. To convert from Ib/ton to kg/Mg, multiply by 0.5.
References For Section 11.14
1. J. L. Spinks, "Frit Smelters", Air Pollution Engineering Manual, Danielson, J. A. (ed.), PHS Publication
Number 999-AP-40, U. S. Department Of Health, Education, And Welfare, Cincinnati, OH, 1967.
2. "MuterialsHandbook", Ceramic Industry, Troy, MI, January 1994.
3. Andrew I. Andrews, Enamels: The Preparation, Application, And Properties Of Vitreous Enamels,
Twin City Printing Company, Champaign, IL, 1935.
4. Written communication from David Ousley, Alabama Department of Environmental Management,
Montgomery, AL, to Richard Marinshaw, Midwest Research Institute, Gary, NC, April 1,1993.
5. Written communication from Bruce Larson, Chi-Vit Corporation, Urbana, OH, to David Ousley,
Alabama Department Of Environment Management, Montgomery, AL, October 10,1994.
6. Written communication from John Jozefowski, Miles Industrial Chemicals Division, Baltimore, MD, to
Ronald E. Myers, U. S. Environmental Protection Agency, Research Triangle Park, NC, September 22,
1994.
11.14-4
EMISSION FACTORS
6/97
-------
7. Particulate Emissions Test Results, No. 2 North Stack, Chi-Vit Corporation, Leesburg, Alabama,
ATC, Inc. Auburn, AL, May 1987.
8. No. 1 South Stack Particulate Test Report, Chi-Vit Corporation, Leesburg, Alabama, April 1989,
ATC, Inc., Auburn, AL, May 1989.
9. Frit Unit No. 2, Scrubber No. 2, Particulate Emission Test Report, Chi-Vit Corporation, Leesburg,
Alabama, April 1991, ATC, Inc., Auburn, AL, April 1991.
10. Diagnostic Test, Dry Gas Cleaning Exhauster Stack, Miles, Inc., International Technology Corporation,
Monroeville, PA, February 1994.
6/97 Mineral Products Industry 11.14-5
-------
-------
11.23 Taconite Ore Processing
11.23.1 General1
The taconite ore processing industry produces usable concentrations of iron-bearing material by
removing nonferrous rock (gangue) from low-grade ore. The six-digit Source Classification Code
(SCC) for taconite ore processing is 3-03-023. Table 11.23-1 lists the SCCs for taconite ore
processing.
Taconite is a hard, banded, low-grade ore, and is the predominant iron ore remaining in the
United States. Ninety-nine percent of the crude iron ore produced in the United States is taconite. If
magnetite is the principal iron mineral, the rock is called magnetic taconite; if hematite is the principal
iron mineral, the rock is called hematic taconite.
About 98 percent of the demand for taconite comes from the iron and steel industry. The
remaining 2 percent comes mostly from the cement industry but also from manufacturers of heavy-
medium materials, pigments, ballast, agricultural products, and specialty chemicals. Ninety-seven
percent of the processed ore shipped to the iron and steel industry is in the form of pellets. Other
forms of processed ore include sinter and briquettes. The average iron content of pellets is 63 percent.
11.23.2 Process Description2'5'41
Processing of taconite consists of crushing and grinding the ore to liberate iron-bearing
particles, concentrating the ore by separating the particles from the waste material (gangue), and
pelletizing the iron ore concentrate. A simplified flow diagram of these processing steps is shown in
Figure 11.23-1.
Liberation is the first step in processing crude taconite ore and consists mostly of crushing and
grinding. The ore must be ground to a particle size sufficiently close to the grain size of the
iron-bearing mineral to allow for a high degree of mineral liberation. Most of the taconite used today
requires very fine grinding. Prior to grinding, the ore is dry-crushed in up to six stages, depending on
the hardness of the ore. One or two stages of crushing may be performed at the mine prior to
shipping the raw material to the processing facility. Gyratory crushers are generally used for primary
crushing, and cone crushers are used for secondary and tertiary fine crushing. Intermediate vibrating
screens remove undersize material from the feed to the next crusher and allow for closed-circuit
operation of the fine crushers. After crushing, the size of the material is further reduced by wet
grinding in rod mills or ball mills. The rod and ball mills are also in closed circuit with classification
systems such as cyclones. An alternative to crushing is to feed some coarse ores directly to wet or dry
semiautogenous or autogenous grinding mills (using larger pieces of the ore to grind/mill the smaller
pieces), then to pebble or ball mills. Ideally, the liberated particles of iron minerals and barren gangue
should be removed from the grinding circuits as soon as they are formed, with larger particles returned
for further grinding.
Concentration is the second step in taconite ore processing. As the iron ore minerals are
liberated by the crushing steps, the iron-bearing particles must be concentrated. Because only about 33
percent of the crude taconite becomes a shippable product for iron making, a large amount of gangue
2/97 Taconite Ore Processing 11.23-1
-------
Table 11.23-1. KEY FOR SOURCE CLASSIFICATION CODES FOR
TACONITE ORE PROCESSING
Keva
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
AA
AB
AC
AD
AE
AF
AG
AH
AI
AJ
AK
AL
AM
Source
Ore storage
Ore transfer
Primary crusher
Primary crusher return conveyor transfer
Secondary crushing line
Secondary crusher return conveyor transfer
Tertiary crushing
Tertiary crushing line
Tertiary crushing line discharge conveyor
Screening
Grinder feed
Primary grinding
Classification
Magnetic separation
Secondary grinding
Conveyor transfer to concentrator
Concentrate storage
Bentonite storage
Bentonite transfer to blending
Bentonite blending
Green pellet screening
Chip regrinding
Grate/kiln furnace feed
Straight grate furnace feed
Vertical shaft furnace feed
Hearth layer feed to furnace
Grate/kiln, gas-fired, acid pellets
Grate/kiln, gas-fired, flux pellets
Grate/kiln, gas- and oil-fired, acid pellets
Grate/kiln, gas- and oil-fired, flux pellets
Grate/kiln, coke-fired, acid pellets
Grate/kiln, coke-fired, flux pellets
Grate/kiln, coke- and coal-fired, acid pellets
Grate/kiln, coke- and coal-fired, flux pellets
Grate/kiln, coal-fired, acid pellets
Grate/kiln, coal-fired, flux pellets
Grate/kiln, coal- and oil-fired, acid pellets
Grate/kiln, coal- and oil-fired, flux pellets
Vertical shaft, gas-fired, top gas stack, acid
pellets
sec
3-03-023-05
3-03-023-04
3-03-023-01
3-03-023-25
3-03-023-27
3-03-023-28
3-03-023-02
3-03-023-30
3-03-023-31
3-03-023-03
3-03-023-34
3-03-023-06
3-03-023-36
3-03-023-17
3-03-023-38
3-03-023-41
3-03-023-44
3-03-023-07
3-03-023-45
3-03-023-08
3-03-023-47
3-03-023-11
3-03-023-49
3-03-023-79
3-03-023-69
3-03-023-48
3-03-023-51
3-03-023-52
3-03-023-53
3-03-023-54
3-03-023-55
3-03-023-56
3-03-023-57
3-03-023-58
3-03-023-59
3-03-023-60
3-03-023-61
3-03-023-62
3-03-023-71
11.23-2
EMISSION FACTORS
2/97
-------
Table 11.23-1. (cont).
Keya
AN
AO
AP
AQ
AR
AS
AT
AU
AV
AW
AX
AY
AZ
BA
BB
BC
BD
BE
BF
BG
BH
b
b
b
b
b
c
c
c
c
c
c
c
Source
Vertical shaft, gas-fired, top gas stack, flux
pellets
Vertical shaft, gas-fired, bottom gas stack, acid
pellets
Vertical shaft, gas-fired, bottom gas stack, flux
pellets
Straight grate, gas-fired, acid pellets
Straight grate, gas-fired, flux pellets
Straight grate, oil-fired, acid pellets
Straight grate, oil-fired, flux pellets
Straight grate, coke-fired, acid pellets
Straight grate, coke-fired, flux pellets
Straight grate, coke- and gas-fired, acid pellets
Straight grate, coke- and gas-fired, flux pellets
Grate/kiln furnace discharge
Vertical shaft furnace discharge
Straight grate furnace discharge
Hearth layer screen
Pellet cooler
Pellet screen
Pellet transfer to storage
Pellet storage bin loading
Secondary storage bin loading
Tertiary storage bin loading
Haul road, rock
Haul road, taconite
Nonmagnetic separation
Tailings basin
Other, not classified
Traveling grate feed
Traveling grate discharge
Indurating furnace: gas-fired
Indurating furnace: oil-fired
Indurating furnace: coal-fired
Kiln
Conveyors, transfer, and loading
sec
3-03-023-72
3-03-023-73
3-03-023-74
. 3-03-023-81
3-03-023-82
3-03-023-83
3-03-023-84
3-03-023-85
3-03-023-86
3-03-023-87
3-03-023-88
3-03-023-50
3-03-023-70
3-03-023-80
3-03-023-93
3-03-023-15
3-03-023-95
3-03-023-16
3-03-023-96
3-03-023-97
3-03-023-98
3-03-023-21
3-03-023-22
3-03-023-18
3-03-023-40
3-03-023-99
3-03-023-09
3-03-023-10
3-03-023-12
3-03-023-13
3-03-023-14
3-03-023-19
3-03-023-20
Defers to labels in Figure 11.23-1.
°Not shown in Figure 11.23-1.
clnactive code.
2/97
Taconite Ore Processing
11.23-3
-------
TACONITEORE
STORAGE (£\
1
®
'
pA PRIMARY CRUSHING (S)
S)\
1
P SECONDARY CRUSHING (I)
O
•
SCREEN
Yorslze
Undersize ore
r— to- TERTIARY CRUSHING ©@|
OvsrsIzQoro
1
©
SCREENING 0|
OVSfStZQ
i
, ©
PRIMARY GRINDING @
CL
J
ASSIFICATION (R) 1
i
'
MAGNETIC SEPARATION (N)
Oversize
^
1 Tailings
SECONDARY GRINDING ©
i
1 1 CLASSIFICATION ©1
©
c • . .. .
HYDRO-SEPARATOR •
1 1
jr TaiHnga
["MAGNETIC SEPARATION (N) ,
CONCENTRATE 1
STORAGE © H*
1 t
u Tailings FLOTATION
CONCENTRATE
THICKENER *•*
V
| DISC FILTERS
"1 *.=
BENTONITE _
STORAGE ©
1. 9 .
(§J | BLENDING (j)
j
CHIP /'""N ^
REGRIND (VJ
(
^
I
BALLING i
DRUMS i
Undersize =
tr ' •
H SCREENING ©|
] Oveisizb
* f~~-
(Zj
INDURATION 6JJJ) TO /AX) ' •* •
i'
^ HEARTH LAYER /f-N5
SCREEN V^§
- a
PELLET COOLING (^c)
•^
PELLET SCREENING /g^\
Ife
PELLET STORAGE
©@@
Figure 11.23-1. Process flow diagram for taconite ore processing.
(Refer to Table 11.23-1 for Source Classification Codes)
11.23-4
EMISSION FACTORS
2/97
-------
is generated. Magnetic separation and flotation are the most commonly used methods for
concentrating taconite ore.
Crude ores in which most of the recoverable iron is magnetite (or, in rare cases, maghemite)
are normally concentrated by magnetic separation. The crude ore may contain 30 to 35 percent total
iron by assay, but theoretically only about 75 percent of this is recoverable magnetite. The remaining
iron is discarded with the gangue.
Nonmagnetic taconite ores are concentrated by froth flotation or by a combination of selective
flocculation and flotation. The method is determined by the differences in surface activity between the
iron and gangue particles. Sharp separation is often difficult.
Various combinations of magnetic separation and flotation may be used to concentrate ores
containing various iron minerals (magnetite and hematite, or maghemite) and wide ranges of mineral
grain sizes. Flotation is also often used as a final polishing operation on magnetic concentrates.
Pelletization is the third major step in taconite ore processing. Iron ore concentrates must be
coarser than about No. 10 mesh to be acceptable as blast furnace feed without further treatment. Finer
concentrates are agglomerated into small "green" pellets, which are classified as either acid pellets or
flux pellets. Acid pellets are produced from iron ore and a binder only, and flux pellets are produced
by adding between 1 and 10 percent limestone to the ore and binder before pelletization Pelletization
generally is accomplished by tumbling moistened concentrate with a balling drum or balling disc. A
binder, usually powdered bentonite, may be added to the concentrate to improve ball formation and the
physical qualities of the "green" balls. The bentonite is mixed with the carefully moistened feed at 5
to 10 kilograms per megagram (kg/Mg) (10 to 20 pounds per ton [lb/ton]).
The pellets are hardened by a procedure called induration. The green balls are dried and
heated in an oxidizing atmosphere at incipient fusion temperature of 1290° to 1400°C (2350° to
2550°F), depending on the composition of the balls, for several minutes and then cooled. The
incipient fusion temperature for acid pellets falls in the lower region of this temperature range, and the
fusion temperature for flux pellets falls in the higher region of this temperature range. The three
general types of indurating apparatus currently used are the vertical shaft furnace, the straight grate,
and the grate/kiln. Most large plants and new plants use the grate/kiln. Currently, natural gas is the
most common fuel used for pellet induration, but heavy oil is used at a few plants, and coal and coke
may also be used.
In the vertical shaft furnace, the wet green balls are distributed evenly over the top of the
slowly descending bed of pellets. A stream of hot gas of controlled temperature and composition rises
counter to the descending bed of pellets. Auxiliary fuel combustion chambers supply hot gases
midway between the top and bottom of the furnace.
The straight grate furnace consists of a continuously moving grate, onto which a bed of green
pellets is deposited. The grate passes through a firing zone of alternating up and down currents of
heated gas. The fired pellets are cooled either on an extension of the grate or in a separate cooler. An
important feature of the straight grate is the "hearth layer", which consists of a 10- to 15-centimeter (4-
to 6-inch) thick layer of fired pellets that protects the grate. The hearth layer is formed by diverting a
portion of the fired pellets exiting the firing zone of the furnace to a hearth layer screen, which
removes the fines. These pellets then are conveyed back to the feed end of the straight grate and
deposited on to the bare grate. The green pellets being fed to the furnace are deposited on the hearth
layer prior to the burning zone of the furnace.
2/97 Taconite Ore Processing 11.23-5
-------
The grate/kiln apparatus consists of a continuous traveling grate followed by a rotary kiln.
The grate/kiln product must be cooled in a separate cooler, usually an annular cooler with counter
current airflow.
11.23.3 Emissions And,Controls2"7'41
Particulate matter (PM) emission sources in taconite ore processing plants are indicated in
Figure 11.23-1. Taconite ore is handled dry through the initial stages of crushing and screening. All
crushers, size classification screens, and conveyor transfer points are major points of PM emissions.
Crushed ore is normally wet ground in rod and ball mills. Because the ore remains wet, PM emissions
are insignificant for the rest of the process until the drying stage of induration. A few plants use dry
autogenous or semi-autogenous grinding and have higher emissions than do conventional plants.
Emissions from crushing and conveying operations are generally controlled by a hood-and-duct
system that leads to a cyclone, rotoclone, multiclone, scrubber, or fabric filter. The inlet of the control
device will often be fed by more than one duct. Water sprays are also used to control emissions.
The first source of emissions in the pelletizing process is the transfer and blending of
bentonite. Additional emission points in the pelletizing process include the main waste gas stream
from the indurating furnace, pellet handling., furnace transfer points (grate feed and discharge), and
annular coolers for plants using the grate/kiln furnace.
Induration furnaces generate sulfur dioxide (SO^. The SO2 originates both from the fuel and
the raw material (concentrate, binder, and limestone). Induration furnaces also emit combustion
products such as nitrogen oxides (NOX), and carbon monoxide (CO). Because of the additional
heating requirements, emissions of NOX and SO2 generally are higher when flux pellets are produced
than when acid pellets are produced.
The combination of multicyclones and wet scrubbers is a common configuration for
controlling furnace waste gas. The purpose of the multicyclones is to recover material from the drying
gases as they pass from the preheat stage to the drying stage. The wet scrubber reduces concentrations
of SO2 and PM in the furnace waste gas. Minor emission sources, such as grate feed and discharge,
are usually controlled by small wet scrubbers.
Annular coolers normally operate in stages. The exhaust of the first-stage cooler is vented to
the indurating furnace as preheated combustion gas. The second and third stages generally are
uncontrolled.
Particulate matter emissions also arise from ore mining operations. The largest source of PM
in taconite ore mines is traffic on unpaved haul roads. Other significant PM emission sources at
taconite mines are tailing basins and wind erosion. Although blasting is a notable emission source of
the various fractions of PM, it is a short-term event, and most of the material settles quickly.
Emissions from taconite ore processing facilities constructed or modified after August 24, 1982
are regulated under 40 CFR 60, subpart LL, Standards of Performance for Metallic Mineral Processing
Plants. The affected emission sources include crushers, screens, conveyors, conveyor transfer points,
storage bins, enclosed storage areas, product packaging stations, and truck and rail loading and
unloading stations. The regulation limits PM stack emissions from these sources to 0.05 grams per
dry standard cubic meter (0.022 grains per dry standard cubic foot). In addition, the opacity of stack
emissions for these sources is limited to 7 percent unless the stack is equipped with a wet scrubber,
11.23-6 EMISSION FACTORS 2/97
-------
and process fugitive emissions are limited to 10 percent. The standard does not affect emissions from
indurating furnaces.
Table 11.23-2 presents the factors for PM emissions from taconite ore indurating furnaces.
Factors for emissions of PM from taconite ore processing sources other than furnaces are presented in
Table 11.23-3. Factors for emissions of SO2, NOX, CO, and CO2 from taconite ore processing are
presented in Tables 11.23-4 and 11.23-5 for acid pellet and flux pellet production, respectively.
Table 11.23-6 presents emission factors for other pollutants emitted from taconite ore indurating
furnaces. Emission factors for fugitive dust sources associated with taconite ore processing can be
estimated using the predictive equations found in Section 13.2 of AP-42, which includes, for the
parameters used in the equations, values based on measurements at taconite ore processing facilities.
2/97 Taconite Ore Processing 11.23-7
-------
Table 11.23-2. EMISSION FACTORS FOR TACONITE ORE INDURATING FURNACES3
Source
Natural gas-fired grate/kiln
(SCO 3-03-023-51,-52)
STatural gas-fired grate/kiln,
with multiclone
(SCO S-03-023-51,-52)
Natural gas-fired grate/kiln, with wet
scrubber
(SCC 3-03-023-5 1.-52)
Natural gas/oil-fired grate/kiln
(SCC 3-03-023-53.-54)
Natural gas/oil-fired grate/kiln,
with ESP
(SCC 3-03-023-53.-54)
Coal/oil-fired grate/kiln, with wet
scrubber
(SCC 3-03-023-61.-62)
Coke-fired grate/kiln, with wet scrubber
(SCC 3-03-023-55.-56)
Coke/coal-fired grate/kiln, with wet
scrubber
(SCC 3-03-023-57.-58)
Gas-fired vertical shaft top gas stack
(SCC 3-03-023-71.-72)
Gas-fired vertical shaft top gas stack,
with multiclone
(SCC 3-03-023-71.-72)
Gas-fired vertical shaft top gas stack,
with wet scrubber
(SCC 3-03-023-71.-72)
Gas-fired vertical shaft top gas stack,
with multiclone and wet scrubber
(SCC 3-03-023-71.-72)
Gas-fired vertical shaft bottom gas stack,
with rotoclone
(SCC 3-03-023-73.-74)
Oil-fired straight grate
(SCC S-03-023-83,-84)
Coke/gas-fired straight grate,
with wet scrubber
(SCC 3-03-023-83.-84)
Filterable15
PM
7.4d
0.44S
0.082J
ND
0.017m
0.19"
0.10p
0.141
16r
1.4s
0.921
0.66"
0.03 11
1.2V
O.llw
EMISSION
FACTOR
RATING
D
D
C
E
E
E
D
D
D
E
D
E
E
D
PM-10
0.63e
0.13h
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
EMISSION
FACTOR
RATTNG
„ E
E
Condensible0
0.022f
NA
0.0055k
0.040"1
ND
ND
ND
ND
ND
ND
0.050*
ND
0.00861
ND
ND
EMISSION
FACTOR
RATING
D
D
D
E
E
11.23-8
EMISSION FACTORS
2/97
-------
Table 11.23-2 (cont).
Applicable to both acid pellets and flux pellets. Emission factors in units of Ib/ton of fired pellets
produced. One Ib/ton is equivalent to 0.5 kg/Mg. Factors represent uncontrolled emissions unless
noted. SCC = Source Classification Code. ND = no data.
b Filterable PM is that PM collected on or prior to the filter of an EPA Method 5 sampling train or
equivalent.
c Condensible PM is that PM collected in the impinger portion of a PM sampling train;
d References 4-5,40.
e Reference 40. •
f References 4,36,39-40. Based on data presented in Reference 40, 84 percent of condensibles
consists of inorganic material.
g References 32-36,39,42-43.
h Reference 39.
J References 20,27,37.
k References 4,37.
m Reference 5.
n Reference 18.
p Reference 29.
q References 26-27.
r References 12-14,24.
s References 12-13,24.
* Reference 45.
u Reference 14.
v Reference 6.
w References 30-31.
2/97 Taconite Ore Processing 11.23-9
-------
Table 11.23-3. EMISSION FACTORS FOR TACONITE ORE PROCESSING
OTHER SOURCESa
Source
Primary crusher, with cyclone
(SCO 3-03-023-01)
Primary crusher, with cyclone and
multiclone
(SCC 3-03-023-01)
Primary crusher, with wet
scrubber
(SCC 3-03-023-01)
Primary crusher, with fabric filter
(SCC 3-03-023-01)
Secondary crushing line, with wet
scrubber
(SCC 3-03-023-27)
Tertiary crusher, with rotoclone
(SCC 3-03-023-02)
Tertiary crushing line, with wet
scrubber
(SCC 3-03-023-30)
Grinder feed, with wet scrubber
(SCC 3-03-023-34)
Hearth layer feed, with wet
scrubber
(SCC 3-03-023-48)
Hearth layer screen, with wet
scrubber
(SCC 3-03-023-93)
Grate/kiln feed, with wet scrubber
(SCC 3-03-023-49)
Grate/kiln discharge
(SCC 3-03-023-50)
Grate/kiln discharge, with wet
scrubber
(SCC 3-03-023-50)
Straight grate feed
(SCC 3-03-023-79)
Straight grate discharge
(SCC 3-03-023-80)
Straight grate discharge, with wet
scrubber
(SCC 3-03-023-80)
Pellet cooler
(SCC 3-03-023-15)
Pellet screen
(SCC 3-03-023-95)
Filterableb
PM
0.25d
0.060d
0.00126
0.0019f
0.00278
0.0013h
0.0016g
0.0011J
0.017k
0.038™
6.6 x 10-5
-------
Table 11.23-3 (cont).
Source
Pellet screen, with rotoclone
(SCO 3-03-023-95)
Primary crusher return conveyor
transfer, with wet scrubber
(SCC 3-03-023-25)
Pellet transfer to storage, with
wet scrubber
(SCC 3-03-023-16)
Secondary crusher return conveyor
transfer, with wet scrubber
(SCC 3-03-023-28)
Conveyor transfer to
concentrator, with wet scrubber
(SCC 3-03-023-41)
Tertiary crushing line discharge
conveyor, with wet scrubber
(SCC 3-03-023-31)
Bentonite storage bin loading, with
wet scrubber
(SCC 3-03-023-07)
Bentonite transfer
(SCC 3-03-023-45)
Bentonite transfer, with wet
scrubber
(SCC 3-03-023-45)
Bentonite blending
(SCC 3-03-023-08)
Bentonite blending, with wet
scrubber
(SCC 3-03-023-08)
Bentonite blending, with fabric
filter
(SCC 3-03-023-08)
Pellet storage bin loading
(SCC 3-03-023-96)
Pellet storage bin loading, with
rotoclone
(SCC 3-03-023-96)
Secondary storage bin loading,
with wet scrubber
(SCC 3-03-023-97)
Tertiary storage bin loading, with
wet scrubber
(SCC 3-03-023-98)
Filterable15
PM
0.037"
0.0003 lf
0.0036™
0.0057V
0.000288
0.0017S
24m
,3.2s
0.11s
19s
0.25s
0.11s
3.7U
0.071"
0.000 19g
0.0018S
EMISSION
FACTOR
RATING
E
E
E
D
E
E
•E
E
E
E
E
E
E
E
E
D
PM-10
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
EMISSION
FACTOR
RATING
Condensable0
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
; ND
ND
ND
ND
ND
ND
EMISSION
FACTOR
RATING
2/97
Taconite Ore Processing
11.23-11
-------
Table 11.23-3 (cont).
a Factors represent uncontrolled emissions unless noted. Emission factors for furnace feed, furnace
discharge, coolers, and product handling are in units of Ib/ton of pellets produced; emission factors
for other sources are in units of Ib/ton of material processed or handled. One Ib/ton is equivalent to
0.5 kg/Mg. SCC = Source Classification Code. ND = no data available.
b Filterable PM is that PM collected on or prior to the filter of an EPA Method 5 (or equivalent)
sampling train.
0 Condensible PM is that PM collected in the impinger portion of a PM sampling train.
d References 10-11.
c Reference 22.
f Reference 27.
6 Reference 28.
^ Reference 6.
J References 7,9.
k References 8-9.
m Reference 8.
n References 4-5.
p Reference 5.
q Reference 4. Condensible inorganic PM fraction only.
r Reference 4.
s Reference 2.
* References 16-17,27.
u Reference 23.
v References 21,28.
11.23-12 EMISSION FACTORS 2/97
-------
Table 11.23-4. EMISSION FACTORS FOR TACONITE ORE INDURATING FURNACES-
ACID PELLET PRODUCTIONa
Source
Natural gas-fired grate/kiln
(SCC 3-03-023-51)
Natural gas-fired grate/kiln,
with wet scrubber
(SCC 3-03-023-51)
Coke-fired grate/kiln
(SCC 3-03-023-55)
Coal/coke-fired grate/kiln,
(SCC 3-03-023-57)
Coal/coke-fired grate/kiln,
with wet scrubber
(SCC 3-03-023-57)
Gas-fired vertical shaft top
gas stack
(SCC 3-03-023-71)
Gas-fired vertical shaft top
gas stack, with wet
scrubber
(SCC 3-03-023-71)
Gas-fired straight grate
(SCC 3-03-023-81)
Gas-fired straight grate, with
wet scrubber
(SCC 3-03-023-81)
Coke-fired straight grate,
with multiclone and wet
scrubber
(SCC 3-03-023-85)
Coke/gas-fired straight-grate
(SCC 3-03-023-87)
SO2b
0.29d
0.053h
1.9k
2.3m
1.5"
ND
0.28P
ND
0.10r
0.99s
ND
EMISSION
FACTOR
RATING
D
D
E
E
D
E
E
D
NOX
1,5"
j
ND
ND
ND
0.2QP
j
ND
ND
ND
0.44r
EMISSION
FACTOR
RATING
D
E
D
CO
0.014f
j
ND
ND
ND
0.077?
j
0.039r
j .
j
0.15r
EMISSION
FACTOR
RATING
D
E
• E
E
CO2°
. 99S
j
99g
998
j
941
j
ND
ND
ND
62s
EMISSION
FACTOR
RATING
C
C
C
C
D
a Emission factors in units of Ib/ton of fired pellets produced. One Ib/ton is equivalent to 0.5 kg/Mg.
Factors represent uncontrolled emissions unless noted. SCC = Source Classification Code. ND =
no data.
Mass balance of sulfur may yield a more representative emission factor for a specific facility than
the SO2 factors presented in this table.
c Mass balance on carbon may yield a more representative emission factor for a specific facility than
the CO2 factors represented in this table.
d References 4,39-40.
e References 19,27,39.
R.Gfcrcncc 39
% References 5,18,29,32-34,39-40,42.
Reference 4.
•> See emission factor for uncontrolled emissions.
k Reference 29.
m Reference 15.
11 References 15,25,29.
p Reference 44.
q References 12-14,24,44-45.
r Reference 31.
s References 30-31.
2/97
Taconite Ore Processing
11.23-13
-------
Table 11.23-5. EMISSION FACTORS FOR TACQNITE ORE INDURATING FURNACES-
FLUX PELLET PRODUCTION3
Source
Natural gas-fired grate/kiln,
with wet scrubber
(SCO 3-03-023-52)
Coal/coke-fired grate/kiln,
with wet scrubber
(SCC 3-03-023-58)
Gas-fired straight grate
(SCC 3-03-023-82)
Pellet cooler
(SCC 3-03-023-15)
SO2b
0.14d
1.5h
ND
Neg.
EMISSION
FACTOR
RATING
D
D
NOX
1.5e
ND
2.5*
ND
EMISSION
FACTOR
RATING
D
D
CO
0.10f
ND
ND
ND
EMISSION
FACTOR
RATING
CO2C
13QS
130S
ND
6.4f
EMISSION
FACTOR
RATING
C
C
E
a Emission factors in units of Ib/ton of fired pellets produced. One Ib/ton is equivalent to 0.5 kg/Mg.
Factors represent uncontrolled emissions unless noted. SCC = Source Classification Code. ND =
no data. Neg. = negligible.
Mass balance of sulfur may yield a more representative emission factor for a specific facility than
the SO2 factors presented in this table.
c Mass balance on carbon may yield a more representative emission factor for a specific facility than
the CO2 factors represented in this table.
d Reference 20.
* References 19,27,39.
f Reference 27. .
S References 20,25-27,36-37.
? References 15,25,29.
J Reference 38.
11.23-14
EMISSION FACTORS
2/97
-------
Table 11.23-6. EMISSION FACTORS FOR TACONITE ORE PROCESSING-
OTHER POLLUTANTS*
EMISSION FACTOR RATING: E
Source
Gas-fired grate/kiln
(SCC 3-03-023-51,-52)
Gas-fired grate/kiln, with multiclone
(SCC 3-03-023-51,-52)
Coke-fired grate/kiln
(SCC 3-03-023-55,-56)
Coke-fired grate/kiln, with wet scrubber
(SCC 3-03-023-55,-56) .
Gas-fired vertical shaft top gas stack
. (SCC 3-03-023-71.-72)
Gas-fired vertical shaft bottom gas stack
(SCC 3-03-023-73,-74)
Gas-fired straight grate furnace, with multiclone and
wet scrubber
(SCC 3-03-023-81,-82)
Gas-fired straight grate furnace, with multiclone and
wet scrubber
(SCC 3-03 -023-85,-86)
Coke/gas-fired straight grate furnace, with multiclone
and wet scrubber
(SCC 3-03-023-87,-88)
Coke/gas-fired straight grate furnace, with multiclone
and wet scrubber
(SCC 3-03-023-87,-88)
Pollutant
VOC
Lead
H2S04
H2S04
VOC
VOC
Lead
Beryllium
Lead
Beryllium
Emission
factor,
Ib/ton
0.0037b
0.075C
0.00050
0.17
0.099
0.013d
0.046d
6.8 x 10'5
2.2 xlO'7
7.6 x 10'5
2.9 x 10'7
References
39
27
39
29
29
44
44
31
31
31
.. - 31
a Factors represent uncontrolled emissions unless noted. All emission factors for furnaces in Ib/ton of
fired pellets produced. One Ib/ton is equivalent to 0.5 kg/Mg. SCC = Source Classification Code.
ND = no data available.
b Based on Method 25A data. EMISSION FACTOR RATING: D.
c Based on Method 25 data.
d Based on Method 25A data.
REFERENCES FOR SECTION 11.23
1.
2.
3.
C.M. Cvetic and P.H. Kuck, "Iron Ore", in: Minerals Yearbook, Vol. I, U. S. Government
Printing Office, 1991, pp. 521-547.
J. P. Pilney and G. V. Jorgensen, Emissions From Iron Ore Mining, Beneficiation And
Pelletization, Volume 1, EPA Contract No. 68-02-2113, Midwest Research Institute,
Minnetonka, MN, June 1983.
A. K. Reed, Standard Support And Environmental Impact Statement For The Iron Ore
Beneficiation Industry (Draft), EPA Contract No. 68-02-1323, Battelle Columbus
Laboratories, Columbus, OH, December 1976.
2/97
Taconite Ore Processing
11.23-15
-------
4. Air Pollution Emissions Test, Eveleth Taconite, Eveleth, MN, EMB 76-IOB-3, U. S.
Environmental Protection Agency, Research Triangle Park, NC, November 1975.
5. Air Pollution Emission Test, Empire Mining Company, Palmer, MI, EMB 76-IOB-2, U. S.
Environmental Protection Agency, Research Triangle Park, NC, November 1975.
6. Emission Testing Report, Reserve Mining Company, Silver Bay, MN, EMB 74-HAS-l, U. S.
Environmental Protection Agency, Research Triangle Park, NC, June 1974.
7. Results Of The January 1977 Particulate Emission Testing Of Crusher Feed Mill Scrubbers
Nos. 2, 3, 5, And 6 Conducted At The Ribbing Taconite Company, Ribbing, MN, Interpoll,
Inc., St. Paul, MN, June 8, 1977.
8. Results Of The June 27-July 1, 1977 Particulate Emission Tests Conducted On Selected
Sources In The Pelletizer Building At The Nibbing Taconite Company Plant, Hibbing, MN,
Interpoll, Inc., St. Paul, MN, August 16, 1977.
9. Phase II Particulate Emissions Compliance Testing, Hibbing Taconite Company, Hibbing,
MN, September 4-6, 1979.
10. Results Of The March 15, 1990 Dust Collector Performance Test On The No. 1 Crusher
Primary Dust Collector At The Cyprus Northshore Mining Facility In Babbitt, MN, Interpoll
Laboratories, Inc., Circle Pines, MN, April 19, 1990.
11. Results Of The March 9, 1990 Dust Collector Performance Test On The No. 1 Crusher
Secondary Collector At The Cyprus Northshore Mining Facility In Babbitt, MN, Interpoll
Laboratories, Inc., Circle Pines, MN, April 18, 1990.
12. Results Of The May 22 And 23, 1984, Dust Collection Efficiency Tests On The D-2 And E-2
Furnace Top Gas Mechanical Collectors At The Erie Mining Company Pellet Plant Near Hoyt
Lakes, MN, Interpoll, Inc., Circle Pines, MN, May 29, 1984.
13. Results Of The December 17, 1981 Compliance Test On The D-2 Furnace Dust Control
System At The Erie Mining Company Pellet Plant Near Hoyt Lakes, MN, Interpoll, Inc., St.
Paul, MN, December 22, 1981.
14. Results Of The February 20, 1980 Particulate Emission Test On The D-l Furnace Top Gas
Wet Collector At The Erie Mining Company Plant Near Hoyt Lakes, MN, Interpoll, Inc.,
St. Paul, MN, March 4, 1980.
15. Results of the October 12-15, 1987 Air Emission Compliance Tests At The Eveleth Taconite
Plant in Eveleth, MN, Interpoll Laboratories, Inc., Circle Pines, MN, December 18, 1987.
16. Results Of The July 9, 1981 Particulate Emission Compliance Test On The Kiln Cooler
Exhaust Stack At Eveleth Mines, Eveleth, MN, Interpoll Laboratories, Inc., St. Paul, MN,
July 22, 1981.
17. Results Of The March 11, 1980 Particulate Emission Compliance Test On The Kiln Cooler
Exhaust Stack At Eveleth Mines, Eveleth, MN, Interpoll, Inc., St. Paul, MN, April 18, 1980.
11.23-16 EMISSION FACTORS 2/97
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18. Results Of The December 13 And 14, 1979 Particulate Emission Compliance Tests On The
Kiln Cooler Exhaust And The 2A Waste Gas Stacks At The Eveleth Expansion Company Plant
Near Eveleth, MN, Interpoll, Inc., St. Paul, MN, January 22, 1980.
19. Results Of The June 12, 1975 Oxides Of Nitrogen Determinations At The Fairlane Plant Pellet
Furnace Wet Scrubber Inlet And Outlet, Eveleth Taconite Company, Eveleth, MN, Interpoll,
Inc., St. Paul, MN, June 30, 1975.
20. Results Of The March/April 1992 Emission Performance Tests On The Nos. 4 And 5 Scrubber
Stacks At The USS Minnesota Ore Operations Facility In Mountain Iron, MN, Interpoll
Laboratories, Inc., Circle Pines, MN, April 23, 1992.
21. Results Of The February 18 And 19, 1992 Particulate Emission Performance Testing On Two
SEI Multiple Throat Venturi Type Wet Scrubber Systems At The USS Minnesota Ore
Operations Facility, Mountain Iron, MN, Interpoll Laboratories, Inc., Circle Pines MN
March 11, 1992.
22. Crusher Environeering Wet Scrubber Dust Collectors Particulate Emissions Compliance
, Testing Ribbing Taconite Company, Hibbing, MN, October 18, 1982.
23. Results Of The June 25 And 26, 1980 Particulate Emission Compliance Tests On The No. 2
Loading Pocket Collector And The Nos. 7 And 8 Pellet Screen Collector At The Erie Mining
Company Plant Near Hoyt Lakes, MN, Interpoll, Inc., St. Paul, MN, July 7, 1980.
24. Results Of The June 12-15, 1984, Dust Collection Efficiency Tests On The D-2 And E-2
Furnace Top Gas Mechanical Collectors At The Erie Mining Company Pellet Plant Near Hoyt
Lakes, MN, Interpoll, Inc., Circle Pines, MN, June 22, 1984.
25. Results Of The August 6, 1991 SO2 Emission Engineering Tests At The USX Minnesota Ore
Operation Facility In Mountain Iron, MN, Interpoll Laboratories, Inc., Circle Pines, MN,
August 15, 1991. ,
26. Results Of The January 25, 1990 Particulate And Sulfur Dioxide Engineering Emission Test
On The Line 7 Grate Kiln At The USX Minnesota Ore Operation Facility, Mountain Iron, MN,
Interpoll Laboratories, Inc., Circle Pines, MN, March 7, 1990.
27. Results Of The March 28-31, 1989 Air Emission Compliance Testing At The USS Plant in
Mountain Iron, MN, Interpoll Laboratories, Inc., Circle Pines, MN, April 21, 1989.
28. Results Of The January 8-10, 1980 Particulate Emission Compliance Tests On Emission
Source Nos. 6.39, 6.40, 6.34, 6.44, 6.41,6.56, 6.43, 8.43, 8.47, And 8.49 At The U.S. Steel
Minntac Plant In Mountain Iron, MN, Interpoll, Inc., St. Paul, MN, February 8, 1980.
29. Results Of The May 21 And 22, 1987 Particulate And SO/SOj Emission Compliance Tests On
The Line 2 Induration Furnace Waste Gas Systems At The Eveleth Taconite Plant In Eveleth,
MN, Interpoll Inc., Circle Pines, MN, June 25, 1987.
30. Results Of The August 6-8, 1986, Particulate And SO2 Compliance Tests On The Indurating
Gas Wet Scrubber Stacks At The Inland Steel Mining Company In Virginia, MN, Interpoll Inc.,
Circle Pines, MN, August 19 1986.
2/97 Taconite Ore Processing 11.23-17
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31. Results Of The May 5-7, 1987, Atmospheric Emission Tests On The Induration Furnaces At
The Hibbing Taconite Company In Hibbing, MN, Interpoll, Inc., Circle Pines, MN, May 14,
1987.
32. Particulate Emissions Testing For National Steel Pellet Company, Keewatin, MN, Waste Gas
Stack No. 2B, June 17, 1992, Shell Engineering and Associates, Inc., Columbia, MO, July 17,
1992.
33. Particulate Emissions Testing For National Steel Pellet Company, Keewatin, MN, Waste Gas
Stack No. 2A, June 5, 1991, Shell Engineering and Associates, Inc. Columbia, MO, June 28,
1991.
34. Particulate Emissions Testing For National Steel Pellet Company, Keewatin, MN, Waste Gas
Stack No. 2B, May 16, 1990, Shell Engineering and Associates, Inc., Columbia, MO, May 30,
1990.
35. Particulate Emissions Testing For National Steel Pellet Company, Keewatin, MN, Waste Gas
Stack No. 2A, June 7, 1989, Shell Engineering and Associates, Inc., Columbia, MO, June 14,
1989.
36. Results Of The October 13, 1994 National Steel Pellet Company Particulate And Visible Waste
Gas Stack 2B Emissions Compliance Test, Barr Engineering Company, Minneapolis, MN,
November 1994.
37. Results Of The April 28, 1993 State Air Emission Compliance Testing On The No. 4 And 5
Pelletizers At The U.S. Steel Plant In Mountain Iron, MN, Interpoll Laboratories, Inc., Circle
Pines, MN, June 10, 1993.
38. Results Of The July 31 And August 1, 1990 NOX Emission Compliance Test On The Flux
Pellet Induration Furnace At The Inland Steel Mining Plant, Interpoll Laboratories, Inc., Circle
Pines, MN, October 10, 1990.
39. Results Of The September 12, 16, 23, And October 12, 1994 National Steel Pellet Company
Waste Gas Stack 2B Emission Tests, Barr Engineering Company, Minneapolis, MN, November
1994.
40. Results Of The March 25, 1994 Air Emission Engineering Tests On The No. 3 Waste Gas
Stack At The U.S. Steel Plant In Mountain Iron, Minnesota, Interpoll Laboratories, Inc., Circle
Pines, MN, April 1994.
41. Written communication from P. O'Neill, Minnesota Pollution Control Association,
Minneapolis, MN, to R. E. Myers, U. S. Environmental Protection Agency,Research Triangle
Park, NC, June 20, 1996.
42. Results of the June 22, 1993 Particulate And Opacity Compliance Tests Conducted On The
No. 2A Waste Gas Stack At The National Steel Pellet Plant In Keewatin, Minnesota, Interpoll
Laboratories, Inc., Circle Pines, MN, July 26, 1993.
11.23-18 EMISSION FACTORS 2/97
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43. Results Of The June 6, 1995 National Steel Pellet Company Particulate Emission Compliance
Test Waste Gas Stack 2A (Emission Point 30), Barr Engineering Company, Minneapolis, MN,
June 1995.
44. Written Communication from D. Koschak, LTV Steel Mining Company, Hoyt Lakes, MN, to
S. Arkley, Minnesota Pollution Control Association, Minneapolis, MN. October 31, 1995.
45. Results Of The July 11-13, 1995 State Air Emission Performance Testing At The LTV Steel
Mining Plant Company Pellet Plant In Hoyt Lakes, Minnesota (Permit No. 48B-95-1/O-1),
Interpoll Laboratories, Inc., Circle Pines, MN, August 28, 1995.
•&U.S. GOVERNMENT PRINTING OFFICE: 1998 -62S-4S3
2/97 Taconite Ore Processing 11.23-19
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1. REPORT NO.
AP-42, Fifth Edition
TECHNICAL REPORT DATA
2. ' '
4. TITLE AND SUBTITLE
Supplement C To
Compilation Of Air Pollutant Emission Factors,
Volume I: Stationary Point And Area Sources
7.AUTHOR(S) '
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Emission Factor And Inventory Group, EMAD (MD 14)
Office Of Air Quality Planning And Standards
U. S. Environmental Protection Agency
Research Triangle Park, NC 27711
12. SPONSORING AGENCY NAME AND ADDRESS
3. RECIPIENTS ACCESSIONNO.
5. REPORT DATE
November 1997
6. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT NO.
1 0. PROGRAM ELEMENT NO.
1 1 . CONTRACT/GRANT NO.
1 3. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
IS. SUPPLEMENTARY NOTES
16. ABSTRACT
This document contains emission factors and process information for more than 200 air pollution source categories.
These emission factors have been compiled from source test data, material balance studies, and engineering estimates, and
they can be used judiciously in making emission estimations for various purposes. When specific source test data are
available, they should be preferred over the generalized factors presented in this document.
This Supplement to AP-42 addresses pollutant-generating activity from Meat Packing Plants, Natural and Processed
Cheese, Bread Baking, Cane Sugar Processing, Sugarbeet Processing, Distilled Spirits, Leather Tanning, Brick And
Structural Clay Product Manufacturing, Frit Manufacturing and Taconite Ore Processing.
17.
a. DESCRIPTORS
KEY WORDS AND DOCUMENT ANALYSIS
b. IDENIMERS/OPEN ENDED TERMS c COSATI Field/Grouo
Emission Factors Area Sources
Emission Estimation Criteria Pollutants
Stationary Sources Toxic Pollutants
Point Sources
18. DISTRIBUTION STATEMENT
Unlimited
1 9. SECURITY CLASS (Report) 21 . NO. OF PAGES
Unclassified 98
20. SECURITY CLASS (Page; 22. PRICE
Unclassified
EPA Form 2220-1 (Rev. 4-77)
PREVIOUS EDITION IS OBSOLETE
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