United States
Environmental Protection
Agency
AIR
Off ice of Air Quality
Planning And Standards
Research Triangle Park, NC 27711
EPA-454/R-98-014
Jury 1998
httpVAww.epa.gov/nWchief
EPA
LOCATING AND ESTIMATING
AIR EMISSIONS FROM SOURCES
OF POLYCYCLIC ORGANIC MATTER
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co
TABLE OF CONTENTS
Section Page
LIST OFTABLES vii
LIST OF FIGURES xv
EXECUTIVE SUMMARY xix
1.0 PURPOSE OF DOCUMENT 1-1
2.0 OVERVIEW OF DOCUMENT CONTENTS 2-1
3.0 BACKGROUND 3-1
3.1 NATURE OF POLLUTANT 3-1
3.2 FORMAT OF POM DATA FOR THE DOCUMENT 3-2
3.3 NOMENCLATURE AND STRUCTURE OF SELECTED
POMs 3-4
3.4 PHYSICAL PROPERTIES OF POM 3-5
3.5 CHEMICAL PROPERTIES OF POM 3-8
3.6 POM FORMATION 3-8
3.6.1 POM from Combustion Processes 3-9
3.6.2 Conversion of POM from Vapor to Particulate 3-11
3.6.3 Persistence and Fate in the Atmosphere 3-16
4.0 POM EMISSION SOURCE CATEGORIES 4-1
4.1 STATIONARY EXTERNAL COMBUSTION 4-1
4.1.1 Residential Heating 4-6
4.1.2 Utility, Industrial and Commercial
Fuel Combustion 4-39
4.2 STATIONARY INTERNAL COMBUSTION 4-108
4.2.1 Reciprocating Engines 4-108
4.2.2 Gas Turbines 4-116
in
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TABLE OF CONTENTS (Continued)
Section Page
4.3 WASTE INCINERATION 4-125
4.3.1 Municipal Waste Combustion 4-125
4.3.2 Industrial and Commercial Waste Incineration 4-140
4.3.3 Sewage Sludge Incineration 4-146
4.3.4 Medical Waste Incineration 4-156
4.3.5 Hazardous Waste Incineration 4-166
4.3.6 Drum and Barrel Reclamation 4-178
4.3.7 Scrap Tire Incineration 4-182
4.3.8 Landfill Waste Gas Flares 4-186
4.4 METAL INDUSTRY 4-190
4.4.1 Primary Aluminum Production 4-190
4.4.2 Sintering in the Iron and Steel Industry 4-226
4.4.3 Ferroalloy Manufacturing 4-231
4.4.4 Iron and Steel Foundries 4-250
4.4.5 Secondary Lead Smelting 4-260
4.5 PETROLEUM REFINING 4-278
4.5.1 Catalytic Cracking Units 4-281
4.5.2 Other Petroleum Refinery Sources 4-290
4.6 ASPHALT PRODUCTS 4-293
4.6.1 Asphalt Roofing Manufacturing 4-293
4.6.2 Hot Mix Asphalt Production 4-310
4.7 COKE PRODUCTION 4-331
4.7.1 Coke Ovens: Charging, Door and Topside Leaks 4-338
4.7.2 Coke Ovens: Pushing, Quenching, and
Battery Stacks 4-381
4.7.3 Coke Byproduct Recovery Plants 4-396
4.8 PORTLAND CEMENT MANUFACTURING 4-403
4.9 PULP AND PAPER INDUSTRY 4-427
4.9.1 Kraft Recovery Furnaces 4-427
4.9.2 Lime Kilns 4-440
IV
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TABLE OF CONTENTS (Continued)
Section
4.9.3 Sulfite Recovery Furnaces 4-442
4.10 OPEN BURNING 4-450
4.10.1 Wildfires and Prescribed Burning 4-450
4.10.2 Open Burning of Scrap Tires 4-460
4.10.3 Agricultural Plastic Film Burning 4-465
4.10.4 Coal Refuse Burning 4-471
4.10.5 Miscellaneous Open Burning 4-479
4.11 MOBILE SOURCES 4-485
4.11.1 Onroad Vehicles 4-485
4.11.2 Aircraft 4-501
4.11.3 Locomotives, Marine Vessels,
and Other Non-road Vehicles and Equipment 4-507
4.12 MISCELLANEOUS SOURCES 4-510
4.12.1 Carbon Black Manufacture 4-510
4.12.2 Wood Treatment/Wood Preserving 4-524
4.12.3 Carbon Regeneration 4-541
4.12.4 Cigarette Smoke 4-548
4.12.5 Wood Charcoal Production 4-553
4.12.6 Crematories 4-562
4.12.7 Gasoline Distribution 4-567
4.12.8 Rayon-Based Carbon Fiber Manufacture 4-574
4.12.9 Commercial Charbroilers 4-578
5.0 EMISSIONS FROM PRODUCTION AND USE OF NAPHTHALENE 5-1
5.1 EMISSIONS FROM NAPHTHALENE PRODUCTION 5-1
5.1.1 Naphthalene from Coal Tar 5-2
5.1.2 Naphthalene from Petroleum 5-9
5.2 EMISSIONS FROM END-USES OF NAPHTHALENE 5-10
5.2.1 Phthalic Anhydride Production 5-11
5.2.2 Naphthalene Sulfonates Production 5-13
5.2.3 Carbamate Insecticide Production 5-14
5.2.4 Moth Repellent Production 5-16
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TABLE OF CONTENTS (Continued)
Section Page
5.2.5 Miscellaneous Uses 5-17
6.0 SOURCE TEST PROCEDURES 6-1
6.1 EPA METHOD 0010 6-1
6.2 EPA METHOD 8270 6-4
6.3 EPA METHOD 8310 6-5
6.4 EPA METHOD TO-13 6-7
6.5 FEDERAL TEST PROCEDURE (FTP) 6-8
APPENDICES
Appendix A - Summary of 7-PAH and 16-PAH Emission Factors A-l
VI
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LIST OF TABLES
Table Eag£
3-1 Physical Properties of Various POM Compounds 3-7
3-2 Percent of Total PAH Associated with Soot Particles
as a Function of Temperature 3-17
3-3 Half Lives in Hours of Selected POM in Simulated Daylight,
Subjected to Varying Concentrations of Atmospheric Oxidants
(Ozone) 3-22
4.1-1 PAH Emission Factors for Conventional Woodstoves 4-11
4.1-2 PAH Emission Factors for Noncatalytic Woodstoves 4-13
4.1-3 PAH Emission Factors for Catalytic Woodstoves 4-16
4.1-4 PAH Emission Factors for Pellet Stoves 4-18
4.1-5 PAH Emission Factors for Fireplaces 4-19
4.1-6 PAH Emission Factors for Residential Coal Boilers and Furnaces 4-25
4.1-7 PAH Emission Factors for Residential Coal Stoves 4-27
4.1-8 PAH Emission Factors for Residential Oil-Fired Combustion Sources 4-30
4.1-9 PAH Emission Factors for Residential Natural
Gas-Fired Combustion Sources 4-32
4.1-10 PAH Emission Factors for Residential Kerosene Heaters 4-35
4.1.2-1 PAH Emission Factors for Wood Waste Combustion 4-64
4.1.2-2 PAH Emission Factors for Industrial Wood Waste Boilers 4-66
4.1.2-3 PAH Emission Factors for Bark-Fired Industrial Boilers 4-68
4.1.2-4 PAH Emission Factors for Wood Waste-Fired Industrial
Boilers > 50,000 Ib steam/hr 4-69
4.1.2-5 PAH Emission Factors for Wood Waste-Fired Industrial
Boilers < 50,000 Ib steam/hr 4-76
vii
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LIST OF TABLES (Continued)
Table Eage
4.1.2-6 PAH Emission Factors for Natural Gas-Fired Utility Boilers 4-78
4.1.2-7 PAH Emission Factors for Natural Gas-Fired Industrial
and Commercial/Industrial Boilers 4-79
4.1.2-8 PAH Emission Factors for Anthracite Coal Combustion 4-80
4.1.2-9 PAH Emission Factors for Coal-Fired Utility Boilers 4-81
4.1.2-10 PAH Emission Factors for Coal-Fired Industrial
and Commercial/Institutional Boilers 4-91
4.1.2-11 PAH Emission Factors for Oil-Fired Boilers 4-95
4.1.2-12 PAH Emission Factors for Oil-Fired Process Heaters 4-101
4.1.2-13 PAH Emission Factors for Waste Oil Combustion 4-102
4.2-1 PAH Emission Factors for Stationary Diesel Internal
Combustion Engines - Reciprocating 4-112
4.2-2 PAH Emission Factors for Stationary Natural Gas-Fired
Internal Combustion Engines - Reciprocating 4-117
4.2-3 PAH Emission Factors for Stationary Internal
Combustion Engines - Gas Turbines 4-123
4.3.1-1 PAH Emission Factors for Municipal Waste Combustion Sources 4-135
4.3.1-2 Summary of Geographical Distribution of MWC Facilities 4-136
4.3.2-1 PAH Emission Factors for Commercial Waste Combustion Sources 4-142
4.3.3-1 PAH Emission Factors for Sewage Sludge Incinerators 4-152
4.3.4-1 PAH Emission Factors for Medical Waste Incinerators 4-163
4.3.5-1 PAH Emission Factors for Hazardous Waste Incinerators 4-175
4.3.6-1 PAH Emission Factors for Drum and Barrel Reclamation 4-179
4.3.7-1 PAH Emission Factors for Scrap Tire Burning 4-184
viii
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LIST OF TABLES (Continued)
Table Eag£
4.3.8-1 PAH Emission Factors for Landfill Flares 4-188
4.4.1 -1 PAH Emission Factors for Primary Aluminum Production:
Paste Preparation, Uncontrolled 4-198
4.4.1 -2 PAH Emission Factors for Primary Aluminum Production:
Paste Preparation, Baghouse Controlled 4-200
4.4.1-3 PAH Emission Factors for Primary Aluminum Production:
Paste Preparation, Dry Scrubber Controlled 4-202
4.4. i .4 PAH Emission Factors for Primary Aluminum Production:
Horizontal-Stud Soderberg Cells 4-204
4.4.1-5 PAH Emission Factors for Primary Aluminum Production:
Vertical-Stud Soderberg Cells, Dry Scrubber Controlled 4-206
4.4.1-6 PAH Emission Factors for Primary Aluminum Production:
Vertical-Stud Soderberg Cells, Wet Scrubber With Dry
Scrubber Controlled 4-208
4.4.1 -7 PAH Emission Factors for Primary Aluminum Production:
Potrooms 4-210
4.4.1-8 PAH Emission Factors for Primary Aluminum Production:
Secondary Roof Vents, Dry Scrubber Controlled 4-212
4.4.1 -9 PAH Emission Factors for Primary Aluminum Production:
Secondary Roof Vents, Wet Scrubber Controlled 4-214
4.4.1-10 PAH Emission Factors for Primary Aluminum Production:
Prebaked Cell 4-217
4.4.1 -11 PAH Emission Factors for Primary Aluminum Production:
Anode Bake Furnace 4-219
4.4.1-12 PAH Emission Factors for Primary Aluminum Production:
Casting Operations 4-221
4.4.1 -13 Primary Aluminum Production Facilities in the United States
in 1992 4-223
IX
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LIST OF TABLES (Continued)
Table Page
4.4.2-1 Locations of Iron and Steel Industry Sinter Plants in 1993 4-229
4.4.3-1 PAH Emission Factors for Open Electric Arc Furnaces
Producing Silicon Metal 4-241
4.4.3-2 PAH Emission Factors for Semi-covered Electric Arc Furnaces
Producing 50 Percent Ferrosilicon 4-242
4.4.3-3 PAH Emission Factors for Covered Electric Arc Furnaces
Producing Ferromanganese 4-244
4.4.3-4 PAH Emission Factors for Covered Electric Arc Furnaces
Producing Silicomanganese 4-246
4.4.3-5 Locations of Ferroalloy Producers in the United States in 1992 4-247
4.4.4-1 PAH Emission Factors for Iron Foundries 4-256
4.4.5-1 PAH Emission Factors for Secondary Lead Smelting 4-274
4.4.5-2 U.S. Secondary Lead Smelters Grouped According
to Annual Lead Production Capacity 4-276
4.5-1 PAH Emission Factors for Petroleum Catalytic Cracking
Catalyst Regeneration Units 4-286
4.6-1 Control Devices Used on POM Emissions Sources
in Asphalt Roofing Plants 4-307
4.6-2 PAH Emission Factors for Asphalt Roofing Manufacturing 4-308
4.6-3 Asphalt Roofing Manufacturers 4-311
4.6-4 PAH Emission Factors for Batch-mix Hot Mix Asphalt Plants 4-324
4.6-5 PAH Emission Factors for Drum-mix Hot Mix Asphalt Plants 4-326
4.6-6 PAH Emission Factors for Hot Mix Asphalt Hot Oil Heaters 4-328
4.7-1 POM Constituents Identified in Coke Oven Gas 4-333
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LIST OF TABLES (Continued)
Table Eag£
4.7-2 Techniques to Control POM Emissions from Emission Points
at Byproduct Coke Plants 4-342
4.7-3 Emission Control Levels for Charging and Door, Lid, and
Offtake Leaks 4-344
4.7-4 BSO Emission Factors for Coke Oven Sources 4-346
4.7-5 POM Emission Factors for Coke Ovens:
Charging, Door, Lid and Offtake Leaks 4-348
4.7-6 Coke Oven Batteries Currently Operating in the United States 4-377
4.7-7 POM Emission Factors for Coke Ovens: Pushing and Battery
Stacks 4-383
4.7-8 POM Emission Factors for Coke Ovens: Quenching 4-389
4.8-1 PAH Emission Factors for Coal/Hazardous Waste-Fired
Wet Process Portland Cement Kilns 4-408
4.8-2 PAH Emission Factors for Coal/Coke/Hazardous Waste-Fired
Wet Process Portland Cement Kilns 4-409
4.8-3 PAH Emission Factors for Hazardous Waste-Fired
Wet Process Portland Cement Kilns 4-410
4.8-4 PAH Emission Factors for Gas/Hazardous Waste-Fired
Wet Process Portland Cement Kilns 4-411
4.8-5 PAH Emission Factors for Coal Coke-Fired
Wet Process Portland Cement Kilns 4-412
4.8-6 PAH Emission Factors for Coal/Coke/Hazardous Waste-Fired
Wet Process Portland Cement Kilns 4-414
4.8-7 PAH Emission Factors for Coal-Fired Wet Process Portland
Cement Kilns 4-416
4.8-8 PAH Emission Factors for Coal/TDF-Fired Wet Process Portland
Cement Kilns 4-417
XI
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LIST OF TABLES (Continued)
Table Page
4.8-9 PAH Emission Factors for Coal/Coke/Hazardous Waste-Fired
Dry Process Portland Cement Kilns 4-418
4.8-10 PAH Emission Factors for Coke/Hazardous Waste-Fired
Dry Process Portland Cement Kilns 4-419
4.8-11 PAH Emission Factors for Coal/Hazardous Waste-Fired
Dry Process Portland Cement Kilns 4-420
4.8-12 PAH Emission Factors for Coal-Fired Precalciner
Dry Process Portland Cement Kilns 4-421
4.8-13 U.S. Portland Cement Plant Locations and Capacity 4-424
4.9.1-1 PAH Emission Factors for Kraft Process Recovery Furnaces 4-434
4.9.1-2 Distribution of Kraft Pulp Mills in the United States (1993) 4-438
4.9.2-1 PAH Emission Factors for Pulp Mill Lime Kilns 4-443
4.9.3-1 PAH Emission Factors for Sulfite Process Recovery Furnaces 4-447
4.9.3-2 Distribution of Sulfite Pulp Mills in the United States (1993) 4-448
4.10.1-1 PAH Emission Factors for Wildfires and Prescribed Burning 4-454
4.10.2-1 PAH Emission Factors for Open Burning of Scrap Tires 4-461
4.10.3-1 PAH Emission Factors for Open Burning of Agricultural Plastic
Film 4-466
4.10.4-1 PAH Emission Factors for Coal Refuse Burning 4-474
4.10.4-2 Unreclaimed Coal Refuse Sites and Associated Acreage 4-476
4.10.5-1 PAH Emission Factors for Miscellaneous Open Burning Sources 4-481
4.11-1 Fleetwide Particulate and Gas-Phase PAH Emission Factors
for On-Road Mobile Sources 4-491
4.11-2 Particulate PAH Emission Factors for Light-Duty Gasoline Vehicles
During the Warm-Engine Operation FTP Driving Cycle 4-494
xn
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LIST OF TABLES (Continued)
Table Page
4.11-3 Gas-Phase Emission Factors for Noncatalyst
Light-Duty Gasoline Vehicles 4-496
4.11 -4 Gas-Phase PAH Emission Factors for Light-Duty Gasoline Vehicles
During the Hot-Start Transient Phase of the FTP Driving Cycle 4-498
4.11.2-1 PAH Emission Concentrations in Aircraft Gas Turbine
Engine Exhaust 4-503
4.11.2-2 PAH Paniculate Emission Factors for Aircraft Gas Turbine
Engines 4-505
4.12.1-1 Stream Code for the Oil-Furnace Process
Illustrated in Figure 4.12.1-1 4-512
4.12.1-2 PAH Emission Factors for Oil Furnace Carbon Black Manufacturing:
Main Process Vent 4-518
4.12.1-3 PAH Emission Factors for Oil Furnace Carbon Black Manufacturing:
Total Process 4-520
4.12.1-4 Location and Annual Capacities of Carbon Black Producers
in 1993 4-522
4.12.2-1 PAH Emission Factors for Creosote Wood Treatment 4-530
4.12.2-2 PAH Emission Factors for Diluent Wood Treatment 4-532
4.12.2-3 PAH Emission Factors for Creosote/Diluent Treated Wood
Storage 4-533
4.12.2-4 List of Creosote Wood Pressure Treatment Plants in the
United States in 1989 4-536
4.12.3-1 Types of Equipment Used for Activated Carbon Regeneration 4-543
4.12.4-1 PAH Emission Factors for Cigarette Smoke 4-550
4.12.6-1 POM Emission Factors for Crematories 4-564
4.12.6-2 1991 U.S. Crematory Locations by State 4-565
Xlll
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LIST OF TABLES (Continued)
Table Page
4.12.7-1 Naphthalene Emission Factors for Gasoline Distribution 4-570
4.12.8-1 PAH Emission Factors for Rayon-Based Carbon Fiber
Manufacturing 4-575
4.12.8-2 Rayon-Based Carbon Fiber Manufacturers 4-576
4.12.9-1 PAH Emission Factors for Commercial Charbroilers 4-579
5-1 Naphthalene Emission Factors for Naphthalene Production 5-5
5-2 U.S. Coke Byproduct Recovery Plants Handling/Processing
Naphthalene 5-7
5-3 Major Producers of Naphthalene-Based Synthetic Tanning Agents
and Surface Active Agents 5-15
5-4 Major Producers of Miscellaneous Naphthalene-Based Chemicals 5-19
xiv
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LIST OF FIGURES
Figure EagS.
3-1 Structures of Selected Polycyclic Aromatic Organic Molecules 3-6
3-2 Hypothesized Ring Closure 3-12
3-3 POM Formation by Pyrolysis 3-13
4.1.2-1 Simplified Boiler Schematic 4-40
4.1.2-2 Single Wall-Fired Boiler 4-42
4.1.2-3 Cyclone Burner 4-44
4.1.2-4 Simplified Atmospheric Fluidized Bed Combuster Process
Flow Diagram 4-45
4.1.2-5 Spreader Type Stoker-Fired Boiler 4-46
4.2-1 Operating Cycle of a Conventional Reciprocating Engine 4-109
4.2-2 Gas Turbine Engine Configuration 4-120
4.3.1-1 Typical Mass Burn Waterwall Combustor 4-126
4.3.1-2 Simplified Process Flow Diagram, Gas Cycle
for a Mass Burn/Rotary Waterwall Combustor 4-127
4.3.1-3 Mass Bum Refractory-Wall Combustor with Grate/Rotary Kiln 4-128
4.3.1-4 Typical RDF-Fired Spreader Stoker Boiler 4-130
4.3.1-5 Typical Modular Starved-Air Combustor with Transfer Rams 4-131
4.3.3-1 Typical Multiple-Hearth Furnace 4-147
4.3.3-2 Fluidized-Bed Combustor 4-149
4.3.4-1 Controlled-Air Incinerator 4-157
4.3.4-2 Excess-Air Incinerator 4-159
4.3.4-3 Rotary Kiln Incinerator 4-161
xv
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LIST OF FIGURES (Continued)
Figure Page
4.3.5-1 Typical Process Component Options
in a Hazardous Waste Incineration Facility 4-168
4.3.5-2 Typical Liquid Injection Combustion Chamber 4-169
4.3.5-3 Typical Rotary Kiln/Afterburner Combustion Chamber 4-170
4.3.5-4 Typical Fixed Hearth Combustion Chamber 4-172
4.4.1-1 General Flow Diagram for Primary Aluminum Reduction 4-191
4.4.1-2 Types of Electrolytic Cells Used in Alumina Reduction 4-193
4.4.1-3 Flow Diagram Depicting the Production of Prebaked Cells 4-194
4.4.2-1 Configuration of a Typical Sintering Facility 4-227
4.4.3-1 Typical Electric Arc Furnace Ferroalloy Manufacturing Process 4-232
4.4.3-2 Open Electric Arc Furnace 4-234
4.4.3-3 Semi-covered Electric Arc Furnace 4-236
4.4.3-4 Covered (Sealed) Electric Arc Furnace 4-237
4.4.4-1 Process Flow Diagram for a Typical Sand-cast Iron and Steel
Foundry 4-252
4.4.4-2 Emission Points in a Typical Iron and Steel Foundry 4-253
4.4.5-1 Simplified Process Flow Diagram for Secondary Lead Smelting 4-261
4.4.5-2 Cross-sectional View of a Typical Stationary Reverberatory
Furnace 4-263
4.4.5-3 Cross-section of Typical Blast Furnace 4-265
4.4.5-4 Side View of a Typical Rotary Reverberatory Furnace 4-268
4.4.5-5 Cross-sectional View of an Electric Furnace for Processing
Slag 4-270
xvi
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LIST OF FIGURES (Continued)
Figure Page
4.5-1 Process Flow Diagram for a Model Petroleum Refinery 4-279
4.5-2 Diagram of a Fluid-bed Catalytic Cracking Process 4-282
4.6.1-1 Asphalt Blowing Process Flow Diagram 4-295
4.6.1-2 Typical Configuration of a Vertical Asphalt Air Blowing Still 4-297
4.6.1-3 Typical Configuration of a Horizontal Asphalt Air Blowing Still 4-298
4.6.1-4 Asphalt-saturated Felt Manufacturing Process 4-300
4.6.1-5 Organic Shingle and Roll Manufacturing Process Flow
Diagram 4-301
4.6.2-1 General Process Flow Diagram for Batch Mix Asphalt Paving
Plants 4-317
4.6.2-2 General Process Flow Diagram for Drum Mix Asphalt Paving
Plants 4-320
4.6.2-3 General Process Flow Diagram for Counter-flow Drum Mix
Asphalt Paving Plants 4-321
4.7-1 View of a Typical Coke Production Plant 4-336
4.7-2 Flow Sheet Showing the Major Steps in the Byproduct Coking
Process 4-337
4.8-1 Process Diagram of Portland Cement Manufacturing by Dry
Process with Preheater 4-405
4.9.1-1 Typical Kraft Pulping and Recovery Process 4-428
4.9.1-2 Direct Contact Evaporator Recovery Boiler 4-430
4.9.1-3 Non-direct Contact Evaporator Recovery Boiler 4-431
4.9.2-1 Process Flow Diagram for a Lime Kiln 4-441
4.9.3-1 Process Diagram for Magnesium-Based Sulfite Pulping and
Chemical Recovery 4-446
xvu
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LIST OF FIGURES (Continued)
Figure Page
4.12.1 -1 Process Flowsheet for an Oil-Furnace Carbon Black
Plant 4-511
4.12.2-1 Flow Diagram of a Wood Preserving Facility Using the
Boulton Conditioning Process 4-526
4.12.3-1 Cross-section of a Typical Multiple-Hearth Furnace 4-542
4.12.3-2 Process Flow Diagram of Carbon Regeneration Process 4-544
4.12.5-1 Missouri-type Charcoal Kiln 4-554
4.12.5-2 Multiple-hearth Furnace for Charcoal Production 4-557
5-1 Coke Oven Byproduct Recovery, Representative Plant 5-3
6.1-1 Modified Method 5 Sampling Train (EPA Method 0010) 6-3
6.5-1 Vehicle Exhaust Gas Sampling System 6-10
xvni
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EXECUTIVE SUMMARY
The 1990 Clean Air Act Amendments contain a list of 188 hazardous air pollutants
(HAPs) which the U.S. Environmental Protection Agency must study, identify sources of, and
determine if regulations are warranted. One of these HAPs, polycyclic organic matter (POM), is
the subject of this document. This document describes the properties of POM as an air pollutant,
how it is formed, identifies source categories of air emissions, and provides POM emissions data
in terms of emission factors. This document is part of an ongoing EPA series designed to assist
the general public at large, but primarily State/local air agencies, in identifying sources of HAPs
and determining emissions estimates.
The principal formation mechanism for POM occurs as part of the fuel combustion
process present in many different types of source categories. A secondary formation mechanism
is the volatilization of light-weight POM compounds. The combustion processes are much more
significant in terms of overall POM air emissions, and include sources such as stationary external
combustion for heat and electricity generation, internal combustion engines and turbines, motor
vehicles, and a variety of fuel combustion processes in the industrial sector.
The term POM defines not one compound, but a broad class of compounds which
generally includes all organic compounds with more than one benzene ring, and which have a
boiling point greater than or equal to 212°F (100°C). Theoretically, millions of POM
compounds could be formed. However, only a small portion of these compounds have actually
been identified and regularly tested for as part of emissions tests.
Sixteen polycyclic aromatic hydrocarbons (PAHs), a subset of the class of POM
compounds, were designated by EPA as compounds of interest under a suggested procedure for
reporting test measurement results.1 The PAHs included in this measurement procedure are:
1 U.S. Environmental Protection Agency. Second Supplement to Compendium of Methods for the
Determination of Toxic Organic Compounds in Ambient Air. Atmospheric Research and
Exposure Assessment Laboratory, Research Triangle Park, North Carolina. EPA-600/4-89-018.
pp. TO-13toTO-97. 1988.
xix
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Naphthalene Benzo(ghi)perylene
Acenaphthene Benz(a)anthracene*
Acenaphthylene Chrysene
Fluorene Benzo(b)fluoranthene*
Phenanthrene Benzo(k)fluoranthene*
Anthracene Benzo(a)pyrene*
Fluoranthene Dibenz(a,h)anthracene*
Pyrene Indeno(l,2,3-cd)pyrene*
The pollutants with asterisks (*) correspond to a subset of seven PAHs that have been identified
by the International Agency for Research on Cancer (IARC) as animal carcinogens and have been
studied by the EPA as potential human carcinogens.'
2 U.S. Environmental Protection Agency. Provisional Guidance for Quantitative Risk Assessment
of Polycyclic Aromatic Hydrocarbons. Office of Research and Development, Washington, DC.
EPA-600/R-93-089. July 1993.
xx
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SECTION 1.0
PURPOSE OF DOCUMENT
The U.S. Environmental Protection Agency (EPA), State, and local air pollution
control agencies are becoming increasingly aware of the presence of substances in the ambient air
that may be toxic at certain concentrations. This awareness, in turn, has led to attempts to
identify source/receptor relationships for these substances and to develop control programs to
regulate emissions. Unfortunately, limited information is available on the ambient air
concentrations of these substances or about the sources that may be discharging them to the
atmosphere.
To assist groups interested in inventorying air emissions of various potentially
toxic substances, EPA is preparing a series of locating and estimating (L&E) documents such as
this one that compiles available information on sources and emissions of these substances. Other
documents in the series are listed below:
Substance or Source Category
Acrylonitrile
Arsenic
Benzene (under revision)
1,3-Butadiene
Cadmium
Carbon Tetrachloride
Chlorobenzenes (revised)
Chloroform
Chromium
Chromium (supplement)
Coal and Oil Combustion Sources
Cyanide Compounds
Epichlorohydrin
Ethylene Oxide
EPA Publication Number
EPA-450/4-84-007a
EPA-454/R-98-011
EPA-450/4-84-007q
EPA-454/R-96-008
EPA-454/R-93-040
EPA-450/4-84-007b
EPA-454/R-93-044
EPA-450/4-84-007c
EPA-450/4-84-007g
EPA-450/2-89-002
EPA-450/2-89-001
EPA-454/R-93-041
EPA-450/4-84-007J
EPA-450/4-84-0071
1-1
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Substance or Source Category
Ethylene Dichloride
Formaldehyde
Lead
Manganese
Medical Waste Incinerators
Mercury and Mercury Compounds
Methyl Chloroform
Methyl Ethyl Ketone
Methylene Chloride
Municipal Waste Combustors
Nickel
Organic Liquid Storage Tanks
Perchloroethylene and Trichloroethylene
Phosgene
Polychlorinated Biphenyls (PCB)
Sewage Sludge Incineration
Styrene
Toluene
Vinylidene Chloride
Xylenes
EPA Publication Number
EPA-450/4-84-007d
EPA-450/2-91-012
EPA-454/R-98-006
EPA-450/4-84-007h
EPA-454/R-93-053
EPA-453/R-93-023
EPA-454/R-93-045
EPA-454/R-93-046
EPA-454/R-93-006
EPA-450/2-89-006
EPA-450/4-84-007f
EPA-450/4-88-004
EPA-450/2-90-013
EPA-450/4-84-007i
EPA-450/4-84-007n
EPA-450/2-90-009
EPA-454/R-93-011
EPA-454/R-93-047
EPA-450/4-84-007k
EPA-454/R-93-048
This document deals specifically with polycyclic organic matter (POM). Its
intended audience includes Federal, State, and local air pollution personnel and others who are
interested in locating potential emitters of POM and estimating their air emissions.
Because of the limited availability of data on potential sources of POM emissions
and the variability in process configurations, control equipment, and operating procedure among
facilities, this document is best used as a primer on (1) types of sources that may emit POM,
(2) process variations and release points that may be expected, and (3) available emissions
information on the potential for POM releases into the air. The reader is cautioned against using
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the emissions information in this document to develop an exact assessment of emissions from
any particular facility. Because of the limited background data available, the information
summarized in this document does not and should not be assumed to represent the source
configuration or emissions associated with any particular facility.
This document represents an update to a previous L&E document for POM that
was published by the EPA in 1987. Since that time there has been new research and testing
associated with some of the source categories that were previously identified. Also, new source
categories emitting POM have been identified and some source categories discussed in the
previous document are no longer in existence. For this update, an effort was made to obtain
more up-to-date information from an extensive literature search. The search was limited to the
years 1986 to the present and to items in the English language.
Databases searched include the following:
Factor Information Retrieval System (FIRE) - which contains
emission factors and other information for a variety of source
categories;
CASEARCH - which contains information on chemistry and
applications literature;
INSPEC - A database of physics, electronics, and computer
abstracts;
NTIS - which contains information on government-sponsored
research, development, engineering, and analysis activities;
COMPENDEX PLUS - A database of literature from the
engineering sciences; and
APILIT - A database maintained by the American Petroleum
Institute, containing information on activities related to the
petroleum industry.
The literature search identified several hundred potential references or citations.
These citations were journal articles, handbooks and texts, Federal and State documents, and
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conference papers. The list of titles and abstracts from the literature search were reviewed to
identify: (1) new information for known source categories, (2) additional source categories, and
(3) test data for categories that were not otherwise well characterized.
Another potential source of emissions data for POM is the Toxic Chemical
Release Inventory (TRI) reporting data required by Section 313 of Title BH of the Superfund
Amendments and Reauthorization Act of 186 (SARA 313). SARA 313 requires owners and
operators of certain facilities that manufacture, import, process, or otherwise use certain toxic
chemicals to report annually their releases of these chemicals to any environmental media. As
part of SARA 313, EPA provides public access to the annual emissions data.
The reader is cautioned that TRI will not likely provide facility, emissions, and
chemical release data sufficient for conducting detailed exposure modeling and risk assessment.
In many cases, the TRI data are based on annual estimates of emissions (i.e., on emission factors,
material balance calculations, and engineering judgment). Also, TRI includes only a limited
number of POM compounds; there are many more POM compounds that are emitted to the air
and which are included in this document. We recommend the use of TRI data in conjunction
with the information provided in this document to locate potential emitters of POM and to make
preliminary estimates of air emissions from these facilities.
As standard procedure, L&E documents are sent to government, industry, and
environmental groups for review wherever EPA is aware of expertise. These groups are given
the opportunity to review the document, comment on its contents, and provide additional data
where applicable. Where necessary, the document is then revised to incorporate these comments.
Although this document has undergone extensive review, there may still be shortcomings.
Comments subsequent to publication are welcome and will be addressed based on available time
and resources. In addition, any information on process descriptions, operating parameters,
1-4
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control measures, and emissions information that would enable EPA to improve on the contents
of this document is welcome. Comments and information may be sent to the following address:
Group Leader
Emission Factor and Inventory Group (MD-14)
Office of Air Quality Planning and Standards
U. S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
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SECTION 2.0
OVERVIEW OF DOCUMENT CONTENTS
This section provides an overview of the contents of this document. It briefly
outlines the nature, extent, and format of the material presented in the remaining sections of this
report.
Section 3.0 of this document provides a brief summary of the physical and
chemical characteristics of POM, its basic formation mechanisms, and its potential
transformations in ambient air. This background section may be useful to someone who needs to
develop a general perspective on the nature of POM, how it is defined, and how it is formed in
the combustion process.
Section 4.0 of this document focuses on major sources of POM air emissions.
Stationary, mobile, and natural sources of POM air emissions are discussed. For each air
emission source category described in Section 4.0, the following subsections are discussed: (1) a
general process description, including emissions control techniques, (2) emission factor
development, and (3) source location. Flow diagrams are provided for most of the
industry-based categories, identifying potential points of emissions. The emission factor
subsections provide a discussion of available data for each source category and present the
emission factors in tabular format. For certain source categories, emission factor data were not
available; in these cases only a process description and source location discussion are provided.
Within the source location subsections, the names and locations of all major stationary source
facilities known to be operating and potentially emitting POM are presented (for industries
having 100 or less facilities). For area sources of POM emissions with distinct national
distributions, and industries with over 100 facilities, geographic areas where such activities
primarily occur are identified.
Section 5.0 describes evaporative emission sources from the production and use of
naphthalene, which is a specific POM compound. Naphthalene is one of the lighter weight POM
compounds that can be emitted through volatilization. The source categories described in
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Section 5.0 involve the direct production and use of naphthalene, which is commercially
produced and widely consumed.
Section 6.0 of this document summarizes available procedures for source
sampling and analysis of POM. The summaries provide an overview of applicable sampling
procedures and cites references for those interested in conducting source tests.
Appendix A provides a summary of emission factors used by the EPA in
developing national emission estimates for POM as part of the supporting data to develop a
national strategy to control POM emissions under Section 112(c)(6) of the Clean Air Act (CAA).
Section 3.2 of this document provides information on the development of the emission factors in
Appendix A.
Each emission factor listed in Sections 4.0 and 5.0 was assigned an emission
factor rating (A, B, C, D, E, or U) based on the criteria for assigning data quality ratings and
emission factor ratings as required in the document Procedures for Preparing Emission Factor
Documents (U.S. EPA, 1997). The criteria for assigning the data quality ratings are as follows:
A - Tests are performed by using an EPA reference test method, or when not
applicable, a sound methodology. Tests are reported in enough detail for
adequate validation, and raw data are provided that can be used to duplicate the
emission results presented in the report.
B - Tests are performed by a generally sound methodology, but lacked enough
detail for adequate validation. Data are insufficient to completely duplicate the
emission result presented in the report.
C - Tests are based on an unproven or new methodology, or are lacking a
significant amount of background information.
D - Tests was based on a generally unacceptable method, but the method may
provide an order-of-magnitude value for the source.
Once the data quality ratings for the source tests had been assigned, these ratings
along with the number of source tests available for a given emission point were evaluated.
Because of the almost impossible task of assigning a meaningful confidence limit to
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industry-specific variables (e.g., sample size versus sample population, industry and facility
variability, method of measurement), the use of a statistical confidence interval for establishing a
representative emission factor for each source category was not practical. Therefore, some
subjective quality rating was necessary. The following emission factor quality ratings were used
in the emission factor tables in this document:
A - Excellent. Emission factor is developed primarily from A- and B-rated
source test data taken from many randomly chosen facilities in the industry
population. The source category population is sufficiently specific to
minimize variability.
B - Above average. Emission factor is developed primarily from A- or
B-rated test data from a moderate number of facilities. Although no
specific bias is evident, it is not clear if the facilities tested represent a
random sample of the industry. As with the A rating, the source category
population is sufficiently specific to minimize variability.
C - Average. Emission factor is developed primarily from A-, B-, and C-rated
test data from a reasonable number of facilities. Although no specific bias
is evident, it is not clear if the facilities tested represent a random sample
of the industry. As with the A rating, the source category population is
sufficiently specific to minimize variability.
D - Below average. Emission factor is developed primarily form A-, B-, and
C-rated test data from a small number of facilities, and there may be
reason to suspect that these facilities do not represent a random sample of
the industry. There also may be evidence of variability within the source
population.
E - Poor. Factor is developed from C- rated and D-rated test data from a very
few number of facilities, and there may be reasons to suspect that the
facilities tested do not represent a random sample of the industry. There
also may be evidence of variability within the source category population.
U - Unrated (Only used in the L&E documents). Emission factor is developed
from source tests which have not been thoroughly evaluated, research
papers, modeling data, or other sources that may lack supporting
documentation. The data are not necessarily "poor," but there is not
enough information to rate the factors according to the rating protocol.
This document does not contain any discussion of health or other environmental
effects of POM, nor does it include any discussion of ambient air levels.
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SECTION 2.0 REFERENCES
U.S. Environmental Protection Agency. Procedures for Preparing Emission Factor Documents.
Research Triangle, North Carolina. EPA-454/R-95-015. November 1997.
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SECTION 3.0
BACKGROUND
3.1 NATURE OF POLLUTANT
The term polycyclic organic matter (POM) defines a broad class of compounds
which generally includes all organic structures having two or more fused aromatic rings
(i.e., rings which share a common border). Further definition is provided in Section 112(b)(l) of
the 1990 Clean Air Act Amendments (CAAA), where POM is listed as a hazardous air pollutant
(HAP) with a footnote stating that it includes organic compounds with more than one benzene
ring, and which have a boiling point greater than or equal to 212°F (100°C). Polycyclic organic
matter has been identified with up to seven fused rings and, theoretically, millions of POM
compounds could be formed; however, only about 100 species have been identified and studied
and typically only a small fraction of these are regularly tested for as part of emissions
measurement programs (U.S. EPA, 1980). Any effort to quantify emissions of POM relies on the
group of compounds or analytes targeted by the test method employed.
Eight major categories of compounds have been defined by the EPA to constitute
the class known as POM (U.S. EPA, 1975; Lahre, 1987). The categories are as follows:
Polycyclic aromatic hydrocarbons (PAHs) - the PAHs include
naphthalene, phenanthrene, anthracene, fluoranthene,
acenaphthalene, chrysene, benz(a)anthracene,
cyclopenta(cd)pyrene, the benzpyrenes, indeno(l,2,3-cd)pyrene,
benzo(ghi)perylene, coronene, and some of the alkyl derivatives of
these compounds. PAHs are also known as polynuclear aromatics
(PNAs).
Aza arenes - aromatic hydrocarbons containing nitrogen in a
heterocyclic ring.
Imino arenes - aromatic hydrocarbons containing a carbon-nitrogen
double bond (C=NH).
Carbonyl arenes - aromatic hydrocarbons containing a one ring
carbonyl divalent group (C=O).
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Dicarbonyl arenes - also known as quinones; contain two ring
carbonyl divalent groups.
Hydroxy carbonyl arenes - carbonyl arenes containing hydroxy
groups and possibly alkoxy or acyloxy groups.
Oxa arenes and thia arenes - oxa arenes are aromatic hydrocarbons
containing an oxygen atom in a heterocyclic ring; thia arenes are
aromatic hydrocarbons containing a sulfur atom in a heterocyclic
ring.
Polyhalo compounds - some polyhalo compounds, such as
polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated
dibenzofurans (PCDFs), may be considered as POM although they
do not have two or more fused aromatic rings.
These categories were developed to better define and standardize the types of compounds
considered to be POM.
The POM chemical groups most commonly tested for and reported in emission
source exhaust and ambient air are PAHs, which contain carbon and hydrogen only. Information
available in the literature and from emissions testing on POM compounds generally pertains to
PAHs. Because of the dominance of PAH information (as opposed to other POM categories) in
the literature, many reference sources have inaccurately used the terms POM and PAH
interchangeably. By definition, all PAH compounds can be classified as POM but not all POM
compounds can be defined as PAHs. This issue becomes important when comparing POM
inventory and emissions data from different references sources where the term "POM" is not
explicitly defined. In these cases POM could represent two entirely different sets of compounds.
and therefore would not be suitable for direct comparison.
3.2 FORMAT OF POM DATA FOR THE DOCUMENT
In order to avoid the historical problems of using a singular "POM" listing for
emission factor data and information, the emission factor tables presented in Sections 4.0 and 5.0
of this report show individual POM compounds, most of which could be classified as PAH. This
3-2
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allows for a direct calculation of emissions for a known compound. The discussions
accompanying each table will generally refer to "POM" compounds when describing processes
or operations that affect the class of compounds as a whole. However, where the information is
specific to PAHs, the discussion utilizes the "PAH" terminology.
The following list of 16 PAHs were designated by EPA as compounds of interest under a
suggested procedure for reporting test measurement results (U.S. EPA, 1988). The 16 PAHs
included in this measurement procedure are:
-Benzo(ghi)perylene
Benz(a)anthracene*
Chrysene*
Benzo(b)fluoranthene*
Benzo(k)fluoranthene *
Benzo(a)pyrene*
Dibenz(a,h)anthracene*
- Indeno( 1,2,3-cd)pyrene*
Naphthalene OGG Q 91 Z,q -z,
-Acenaphthene
Acenaphthylene
Fluorene OQ -7~>f 2 l>'IJ
Phenanthrene ^ ^:J ° Y ^ "
I
Anthracene ' "
Fluoranthene
Pyrene
These 16 compounds are routinely detected and reported from source tests as they are target
analytes in standard EPA and State sampling and analytical methods. The pollutants with
asterisks (*) correspond to the subset of seven PAHs. These seven PAHs have been identified by
the International Agency for Research on Cancer (IARC) as animal carcinogens and have been
studied by the EPA as potential human carcinogens (U.S. EPA, 1993).
The emission factor tables in Sections 4.0 and 5.0 first list all of the 7-PAH
compounds. The rest of the 16-PAH group of compounds are listed next. Other POM
compounds that are not part of the 16-PAH subset are listed at the end of each table. For some
source categories, there were not individual PAH emission factors for all 16 PAHs in the subset;
therefore, the list of compounds varies from source to source in some cases. However, in all
cases, the order of pollutants begins with compounds from the 7-PAH subset; followed by the
3-3
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remaining compounds from the 16-PAH grouping, and finally, any other POM compounds for
which emission factor data were found.
Appendix A provides a summary of 7-PAH and 16-PAH emission factors for
source categories for which the EPA has developed national emission estimates to meet the
requirements of Section 112 (c)(6) of the CAAA. Section 112 (c)(6) requires the EPA to look at
seven specific pollutants, including POM, in order to develop a national strategy to control these
pollutants. The source categories listed in Appendix A do not represent all the potential POM
source categories discussed in this document. The EPA did not always have activity levels to
match to the available emission factors for every source category, so Appendix A only contains
those categories for which an activity level was available to calculate national emissions.
The 7-PAH and 16-PAH emission factors in Appendix A are presented as the sum
of the individual POM compounds making up the 16-PAH and 7-PAH subsets as described
above. For most of the source categories listed in Appendix A, the 16-PAH and 7-PAH emission
factors were derived from the individual POM compound emission factors presented in the
emission factor tables in this document. The exceptions are the "Ferroalloy Manufacturing" and
the "Onroad Vehicles" source categories; the 16-PAH and 7-PAH emission factors contained in
Appendix A for these source categories were developed by EPA specifically for the purpose of
the national emission inventory efforts and were not derived from the emission factor tables
contained in this document for those categories. The 16-PAH and 7-PAH emission factors for
these categories were developed by EPA from alternative sources for which background
information on the individual POM compounds included in the 16-PAH and 7-PAH subsets was
not available to present in a consistent format with this document (i.e., individual POM species
factors were not available). When using the emission factors in Appendix A, the user should
keep in mind that these were developed to be representative of nationwide activity and do not, in
many cases, represent the particularities of a specific site. If modeling specific site conditions, or
if the focus is on individual POM compounds, the user should refer to the emission factor tables
for the particular source category contained in this document.
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Because POM is not one compound but potentially several thousand, it is not
reasonable to describe the properties and characteristics of all POM compounds. Instead, general
background information is provided for the primary POM compounds, such as PAHs, that are
known to exist in ambient air. Considerably more detailed data on POM chemical and physical
properties exist than are presented in this document. The prevalent, more useful information is
presented here to provide an understanding of the basic nature of POM compounds and
emissions. The references cited at the end of each section contain useful information and should
be consulted when further detail is required.
3.3 NOMENCLATURE AND STRUCTURE OF SELECTED POMs
In the past, the nomenclature of POM compounds has not been standardized and
ambiguities have existed due to different peripheral numbering systems. The currently accepted
nomenclature is that adopted by the International Union of Pure and Applied Chemistry (IUPAC)
and by the Chemical Abstracts Service Registry (National Academy of Sciences, 1972). The
following rules help determine the orientation from which the numbering is assigned:
1. The maximum number of rings lie in a horizontal row;
2. As many rings as possible are above and to the right of the
horizontal row; and
3. If more than one orientation meets these requirements, the one with
the minimum number of rings at the lower left is chosen (Loening
and Merrit, 1983).
The carbons are then numbered in a clockwise fashion, starting with the first
counterclockwise carbon which is not part of another ring and is not engaged in a ring fusion.
Letters are assigned in alphabetical order to faces of rings, beginning with "a" for the side
between carbon atoms 1 and 2 and continuing clockwise around the molecule. Ring faces
common to two rings are not lettered. The molecular structures of the more predominantly
identified and studied POM compounds (mainly PAHs) are shown in Figure 3-1.
3-5
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Ntpntntltn*
AntfirteciM
Fluor»nth«n«
B«nto( gh 1) f 1 uertntMn*
Cyelop*nt*(cd)eyi
B*n X («) an th r*c«n«
B«nio( J) fl uorantn*n«
8*nx(«)«ctn«ptttny1*rw
B«nzo(k)f1uor*nth«fM
B«nio(«)pyr»o«
tenxo(ghi)p«ry1«rw
B««xo
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3.4 PHYSICAL PROPERTIES OF POM
Most POM compounds are solids with high melting and boiling points and are
extremely insoluble in water. The PAHs are primarily planar, nonpolar compounds with melting
points considerably over 212°F (100°C). Phenanthrene, with a melting point of 214°F (101 °C)
and benzo(c)phenanthrene, with a melting point of 154°F (68 °C) are two exceptions. The
molecular weights, melting points, and boiling points of selected POM species are listed in
Table 3-1.
The vapor pressures of POM compounds vary depending upon the ring size and
the molecular weight of each species. The vapor pressure of pure compounds varies from
6.8 x 10"4 mmHg for phenanthrene (3 rings and 14 carbons) to 1.5 x 10~12 mrnHg for coronene
(7 rings and 24 carbons) (U.S. EPA, 1978). A POM compound's vapor pressure has
considerable impact on the amount of POM that is adsorbed onto particulate matter in the
atmosphere and retained on particulate matter during collection of air sampling and during
laboratory handling. Retention of POM species on particulates during collection and handling
also depends upon temperature, velocity of the air stream during collection, properties of the
particulate matter, and the adsorption characteristic of the individual POMs. Table 3-1 includes
vapor pressures at 86°F (30°C) for selected POMs.
The ultraviolet absorption spectra are available for many POM compounds. Most
of the polycyclic aromatic hydrocarbons absorb light at wavelengths found in sunlight (>300 nm)
and are believed to be photochemically reactive by direct excitation. The available spectra data
reflect characteristics of PAHs in organic solvents; however, PAHs in the environment are
usually particulate-bound and as such may have considerably different absorption properties.
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TABLE 3-1. PHYSICAL PROPERTIES OF VARIOUS POM COMPOUNDS
u>
00
Compound
Napthalene
Acenaphthene
Fluorene
Anthracene
Phenanthrene
Fluoranthene
Pyrene
Benz(a)anthracene
Chrysene
Benzo(a)pyrene
Benzo(k)fluoranthene
Perylene
Benzo(ghi)perylene
Dibenz(a,h)anthracene
Coronene
Chemical Formula
cioH8
C)2H,0
^13^10
CI4H10
CH^IO
C16HIO
CI6H10
C|gH12
C,gH12
C20H,2
C20H,2
C20H,2
C22H12
C22H14
C24HI2
Molecular Weight Melting Point °F (°C) Boiling Point3 °F (°C)
128.19
154.21
166.22
178.24
178.24
202.26
202.26
228.30
228.30
252.32
252.32
252.32
276.33
278.36
300.36
177 (80.5)
187 (96.2)
241-243(116- 117)
422-423(216.5-217.2)
212-214(100- 101)
231-232(110.6-111.0)
306-307(152.2-152.9)
319-321(159.5- 160.5)
482-489(250-254)
350-352(176.5-177.5)
420-421(215.5-216)
523-525 (273 - 274)
523 (273)
401 (205)
820(438)
424(218)
534 (279)
563 (295)
644 (339.9)
644 (340)
739 (393)
680 (360)
815 (435)
838 (448)
592(311)
NR
932 (500)
NR
NR
977 (525)
Vapor Pressure1"
(mmHg)
NRC
NR
NR
1.95x IQ-*
6.8 x W4
NR
6.85 x 10'7
1.1 x 10'7
NR
5.5 x 10 9
9.6x10-"
NR
1.01 x 10-'°
NR
1.47X10'12
'Each boiling point is at a pressure of 1 atm, except the boiling point of benzo(a)pyrene is at a pressure of 10 mmHg.
bAll vapor pressures are at 86°F (30°C).
CNR means data not reported.
Sources: U.S. EPA, 1980; Tucker, 1979; U.S. EPA, 1978; CRC, 1983.
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3.5 CHEMICAL PROPERTIES OF POM
The chemistry of POMs is quite complex and differs from one compound to
another. Most of the information available in the literature concerns the polycyclic aromatic
hydrocarbons. Generally, the PAHs are more reactive than benzene and the reactivities toward
methyl radicals tend to increase with greater conjugation. Conjugated rings are structures which
have double bonds that alternate with single bonds. Conjugated compounds are generally more
stable but, toward free radical addition, they are more reactive (Morrison and Boyd, 1978). For
example, in comparison to benzene, naphthalene and benz(a)anthracene, which have greater
conjugation, react with methyl radicals 22 and 468 times faster, respectively.
The PAHs undergo electrophilic substitution reactions quite readily. An
electrophilic reagent attaches to the ring to form an intermediate carbonium ion; to restore the
stable aromatic system, the carbonium ion then gives up a proton. Oxidation and reduction
reactions occur to the stage where a substituted benzene ring is formed. Rates of electrophilic,
nucleophilic, and free radical substitution reactions are typically greater for the PAHs than for
benzene.
Environmental factors also influence the reactivity of PAHs. Temperature, light,
oxygen, ozone, other chemical agents, catalysts, and the surface areas of particulates that the
PAHs are adsorbed onto may play a key role in the chemical reactivity of PAHs.
3.6 POM FORMATION
The principle formation mechanism for POM occurs as part of the combustion
process present in many different types of sources. A secondary formation mechanism, primarily
represented by the naphthalene production and use categories (see Section 5.0 of this document),
is the volatilization of light-weight POM compounds. However, the combustion mechanism is
much more significant when looking at overall POM formation, and it also much more complex.
The following discussion focuses on the combustion mechanism for POM formation.
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3.6.1 POM from Combustion Processes
POM formation occurs as a result of combustion of carbonaceous material under
reducing conditions. The detailed mechanisms are not well understood; however, it is widely
accepted that POM is formed via a free radical mechanism which occurs in the gas phase
(Natusch et al., 1978). As a result, POM originates as a vapor. There is also overwhelming
evidence that POM is present in the atmosphere predominantly in paniculate form
(Thomas et al., 1968). Therefore, a vapor to particle conversion must take place between the
points of formation of POM in the combustion source and its entry to the atmosphere.
It has been recognized that soot (a product of coal combustion) is similar in some
structural characteristics to polycyclic aromatic molecules and that both soot and POM are
products of combustion (Electric Power Research Institute [EPRI], 1978). Comparisons of the
two types of molecules give rise to the first clue as to how POM may be formed in combustion,
namely by incomplete combustion and degradation of large fuel molecules such as coal. It is also
known, however, that carbon black and soot are produced by burning methane (CH^. Thus, it is
believed that POMs are not only produced by degrading large fuel molecules, but are also
produced by polymerizing small organic fragments in rich gaseous hydrocarbon flames. Before
examining POM formation per se, it is instructive to first examine carbon (soot) formation in
combustion. The two are similar phenomena and a closer examination of some of the earlier
studies on soot formation is helpful in understanding POM formation and behavior.
Soot produced in a flame takes on a number of specific characteristics. Soot or
carbon particles may be hard and brittle, soft and fatty, brown to black, and contain anywhere
from almost 0 to 50 percent hydrogen (based on number of atoms). Generally, it is observed that
flame-produced soot is a fluffy, soft material made up of single, almost spherical particles which
stick together. Soot properties appear to be independent of the fuel burned in a homogeneous gas
flame. However, if hydrocarbon gases (such as methane, propane, or benzene) are passed down a
hot tube, the carbon product is quite different from the flame-produced soot. The heterogeneous
products are hard, long crystals that are shiny and vitreous.
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Carbon-producing flames have been identified and labeled as either the acetylenic
type or the benzene type. The acetylenic type flame is one in which carbon, as observed in
C2-radiation, is emitted from all parts of the flame. Carbon compounds produced in low
molecular weight hydrocarbon flames is made up of benzene and other aromatics (benzene type).
Instead of C2-radiation being emitted from all parts of the flame, a carbon streak is observed that
is emitted from the tip of the flame. The basis for the two flame types is related to differences in
diffusion properties between the fuel molecule and oxygen. Where the fuel and oxygen are of
about the same molecular weight, carbon is observed uniformly in the flame front; where the two
differ substantially, enriched pockets of fuel and oxygen occur, and one observes the carbon
streak. Thus, the nature of the soot molecule may be independent of the fuel molecule, but its
formation is quite dependent on the nature of the fuel and on the method of combustion.
Over the past 25 years, procedures have been developed for analyzing the
microstructure and detailed kinetics of processes occurring in flames. A number of investigators
have been applying these techniques to studying POM formation in gaseous hydrocarbon flames
(Howard and Longwell, 1983; Toqan et al., 1983). In one procedure, a pre-mixed
hydrocarbon-air flame is stabilized on a burner (usually as a flat flame) and reactants and
products are removed with the aid of a microprobe and analyzed by electron microscope or other
techniques.
Changes in the molecular weight of POM products as they pass through the flame
have been documented. Just above the flame, a large number of POM products are observed,
while farther downstream the number of products is considerably reduced. Based on this
observation, it appears that a large number of reactive POM products are produced just past the
flame zone. These POMs are referred to as reactive POMs, in that they contain many organic
side chains (CH2, C2H5, etc.) attached to the rings of the basic POM structures. The reactive
POMs, however, degrade in the hot region of the flames so that further downstream only the
more stable condensed ring structures are observed.
The changes in POM structure noted above are corroborated in other studies. It
has been shown that with time a steady increase occurs in the production of lower molecular
3-11
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weight POMs (e.g., anthracene, phenanthrcne, fluoranthene, and pyrene), while the higher
molecular weight POMs such as benzopyrcne, benzoperylene, and coronene reach a maximum
and then decline in concentration with increasing distance from the flame. Studies by
Toqan et al. (1983) show that soot is formed in the region of the flame where a sharp decline of
POM compound is observed. They conclude that the POM (particularly PAH) compounds are
precursors to soot formation. From the preceding discussion, it is apparent that POM may be a
precursor as well as a byproduct of soot formation.
The question of how the polyacetylenes (that are produced by a sequence of rapid
reaction steps) cyclize still remains. One theory is that the polyacetylene chain bends around the
carbon atoms and eventually bonds into the condensed ring structures. Another plausible
hypothesis is illustrated in Figure 3-2. The association shown requires minimum atomic
rearrangements. Also, the formation of polyacetylene cyclics is highly exothermic, thereby
providing sufficient energy to dissociate terminal groups and the free valences to produce
reactive and stable POMs.
Pyrolytic studies of aromatic and straight chain hydrocarbons have been
conducted which offer logical mechanisms for explaining POM formation (Crittenden and Long,
1976). An example explaining the formation of fluoranthene, phenanthrene, and benzo(a)pyrene
is shown in Figure 3-3. In this instance, the example illustrates how phenyl-, butadienyl-, and
phenyl butadienyl radicals produced in the pyrolysis of phenylbutadiene may react with
naphthalene to produce the three POM products.
In conclusion, there is no single, dominant mechanism for POM formation in
flames. In rich gas flames, polyacetylenes can be built up via a C2H polymerization mechanism.
In coal and oil droplet flames, pyrolytic degradation mechanisms prevail. In either instance, soot
and POM are related and persist in post-rich flames due to a deficiency of hydroxide radicals.
3-12
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f t f
—c=c—c=c—c=c—c=c—
rill
L L L '_
C ~"~~ C ^~" C 3ZIC """^C zziC ""^C mz C"
* » , *
I
Source: EPRI, December 1978.
Figure 3-2. Hypothesized Ring Closure
3-13
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U)
+ Butadienyl
Radical
+ Phenyl Butadienyl
Radical
3,4-BENZOPYRENE
N
IK
0.
2
Figure 3-3. POM Formation by Pyrolysis
Source: EPRI, December 1978.
-------
3.6.2 Conversion of POM from Vapor to Particulate
Polycyclic organic matter formed during combustion is thought to exist primarily
in the vapor phase at the temperatures encountered near the flame. However, POM encountered
in the ambient atmosphere is almost exclusively in the form of particulate material (Schure et al.,
1982). It is thought that the vapor phase material formed initially becomes associated with
particles by adsorption as the gas stream cools or possibly by condensation and subsequent
nucleation (Schure et al., 1982; National Academy of Sciences, 1983). The lack of open-channel
porosity, the large concentration of oxygen functional groups on the surface of particulates such
as soot, and the adherence of airborne benzo(a)pyrene to the particle in a manner that allows for
ready extraction indicate that benzo(a)pyrene and presumably other POM compounds are
primarily adsorbed on the surface of particulates through hydrogen bonding.
The physical state of POM in ambient air is determined in part by the amount of
particulate generated by the source. Natusch and Tomkins contend that the extent of POM
adsorption onto particulate is proportional to the frequency of collision of POM molecules with
available surface area, resulting in preferential enrichment of smaller diameter particulates
(Natusch and Tomkins, 1978). In areas of high particulate concentrations, such as the stack of a
fossil fuel power plant, one would expect nearly complete adsorption of the POM onto
particulates. As particulate concentration decreases, as in internal combustion engines, one
would expect to find more POM in the condensed phase. In general, the largest concentration of
POM per unit of particulate mass will be found in the smaller diameter aerosol particulates.
Natusch has developed a detailed mathematical model describing the adsorption and
condensation mechanisms of POM compounds (Natusch, 1978). The model can describe the
temperature dependence of both adsorption and condensation for several different surface
behavioral scenarios.
While both adsorption and condensation may be in operation, it appears that the
POM vapor pressures encountered in most combustion sources are not high enough for
condensation or nucleation to occur (see Table 3-1). The saturation vapor pressure or dew point
of POM must be attained for these processes to take place. Conversely, adsorption of POM
3-15
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vapor onto the surface of paniculate material present in stack or exhaust gases can certainly take
place and could account for the occurrence of the paniculate POM at ambient atmospheric
temperatures. Specifically, the modeling exercises conducted by Natusch have shown that:
1. The most important parameters to be considered in an adsorption
model are the adsorption energetics, the surface area, and the vapor
phase concentration of the adsorbate.
2. Surface heterogeneity will broaden the temperature range where
adsorption becomes significant.
3. The particle surface temperature determines the adsorption
characteristics. The gas phase temperature is of secondary
importance.
4. For conditions found in a typical coal-fired power plant,
homogenous condensation is not highly favored since vapor phase
levels of POM are, in most cases, below the saturated vapor
concentration.
5. The kinetics of adsorption are predicted to be fast, suggesting that
an equilibrium model may be adequate for modeling the adsorption
behavior of POM (Natusch, 1984).
Field measurement studies have been conducted to investigate the occurrence of
vapor to particle conversion in a combustion source (DeAngelis et al., 1979). Measurements
were made in the stack system and in the emitted plume of a small coal-fired power plant
possessing no particle control equipment. Fly ash samples were collected during the same time
periods both inside the stack (temperature at 554°F [290°C]) and from the emitted plume
(temperature at 41 °F [5°C]). Collected material was extracted and analyzed for POM. Only
crude vapor traps were employed during sample collection so no quantitative measure of vapor
phase POM was obtained. It was assumed that all POM collected was in the paniculate phase.
The results of this field test show that considerably more paniculate POM is associated with fly
ash collected from the plume at a temperature of 41 °F (5°C) than from that collected from the
same stream at a temperature of 554°F (290°C). Furthermore, since the two collection points
were only 100 ft (30.5 m) apart, quite rapid vapor to particle conversion is indicated.
3-16
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Laboratory studies have been conducted to determine the rate and extent of POM
adsorption onto paniculate matter. In one study, a stream of air containing pyrene was passed
over a bed of fresh coal fly ash which had previously been shown to contain no detectable POM
(Sonnichsen, 1983). The objective was to expose all particles to the same concentration of
pyrene for different amounts of time and to determine the specific concentrations of adsorbed
pyrene as a function of time at different temperatures. The results of this experiment showed that
the amount of adsorbed pyrene required to saturate the fly ash increased significantly with
decreasing temperature. The rate at which the adsorption process takes place, even at ambient
temperatures, is very rapid; on the order of a few seconds. In another study, PAH and soot were
sampled from the exhaust gases of a laminar, premixed flat flame under laboratory conditions
(Prado et al., 1981). Sampling at different filter temperatures was studied to assess partitioning
of PAH between vapor phase and soot. The data shown in Table 3-2 indicate that at low
temperatures (104°F [40°C]), the compounds were adsorbed or condensed on the soot particles,
while at high temperatures (392°F [200°C]), only the heaviest species were condensed to any
significant extent. While these experiments are essentially qualitative, they do establish that coal
fly ash and soot will strongly adsorb various POM species, and that the saturation capacity of the
adsorbate is inversely related to temperature.
3.6.3 Persistence and Fate in the Atmosphere
Polycyclic organic matter emitted as primary pollutants present on paniculate
matter can be subject to further chemical transformation through gas-particle interactions
occurring either in exhaust systems, stacks, emission plumes, or during atmospheric transport.
When emitted into polluted urban atmospheres, especially areas with photochemical smog that
has a high oxidizing potential, particle-adsorbed PAH are exposed to a variety of gaseous
co-pollutants. These include highly reactive intermediates (both free radicals and excited
molecular species) and stable molecules. Seasonal variation in transformation reactions of PAH
have been observed. During winter, with conditions of low temperature and low irradiation, the
major pathway for PAH degradation is probably reactions with nitrogen oxides, sulfur oxides and
with the corresponding acids. During summer months, with conditions of high temperatures and
intense irradiation, photochemical reactions with oxygen and secondary air pollutants produced
3-17
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TABLE 3-2. PERCENT OF TOTAL PAH ASSOCIATED WITH SOOT
PARTICLES AS A FUNCTION OF TEMPERATURE
Compound
Naphthalene
Methylnaphthalene
Biphenyl
Biphenylene
Fluorene
Phenanthrene and
Anthracene
4H-Cyclopenta-
(def)phenanthrene
Fluoranthene
Pyrene and
Benzacenaphthylene
104°F
(40°C)
56
39
89
88
98
90
97
99
99
131°F
(55 °C)
6.5
a
77
70
94
92
b
b
b
185°F
(85 °C)
4.3
20
48
66
b
71
85
82
83
392°F
(200°C)
0.11
0.00
0.46
0.09
2.1
4.6
2.3
38
33
aGC/MS analysis not available.
blnterferences from contaminants; accurate values not determined.
Source: Pradoetal., 1981.
3-18
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by photolysis, such as ozone and hydroxyl and hydroperoxyl radicals, are important
(Van Cauwenberghe, 1985).
The PAH group of POM compounds in pure solid or solution form undergo
different transformation rates than PAH adsorbed onto other substrates. Because atmospheric
PAH is predominately found adsorbed onto particulates, transformation mechanisms discussed in
this section concentrate on that form. Numerous studies have shown differences in
transformation reactions when various PAHs are present as a pure solid, in solution, or adsorbed
onto other solid substrates (Natusch et al., 1978; National Academy of Sciences, 1983;
Taskar et al., 1985; Yokley et al., 1986).
Atmospheric Physics
Because of the high melting and boiling points of materials classified as POM, the
bulk of POM is believed to be linked to aerosols in the atmosphere. As POM is mixed with
aerosols in the atmosphere, it is spread among particles of widely varied sizes by collision
processes. In one study, DeMaio and Corn found that more than 75 percent of the weight of
selected polycyclic hydrocarbons was associated with aerosol particles less than 2.5 /u.m in radius
(DeMaio and Corn, 1966). However, Thomas et al. (1968) found that the amount of
benzo(a)pyrene per unit weight of soot was constant in the sources tested. A problem in
determining the size fractionation of POM-containing aerosols may be due to the sampling
methods. Some of the POM may be lost by vaporization from the smaller particles during
sample collection. Katz and Pierce observed that the size-mass distribution of PAH-containing
particulates varied with collection site. Paniculate sampling near vehicular traffic resulted in a
group of PAH-particulate compounds in the submicron range, presumably from exhaust, and a
second group of large size PAH-particulates (>7.0 /zm), presumably from roadway reentrainment
(Katz and Pierce, 1976). Sampling stations located away from highways resulted in over
70 percent of the PAH-particulate mass associated with particles less than or equal to 1.0 /urn in
diameter, which is in agreement with earlier studies.
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Particles containing POM are dispersed in air and may be transported great
distances from their origin by winds. They are eventually removed from the atmosphere by
sedimentation or deposition. Removal is enhanced by washout from under rain clouds and by
rainout from within clouds (National Academy of Sciences, 1972; Van Noort and Wondergem,
1985). Deposition of large particles by gravitational settling is important, as well as deposition
by impaction as air masses flow around obstacles such as rocks, building and vegetation.
Rain clouds play an important role in the removal of POM-laden aerosols from
the atmosphere. Aerosols provide centers for nucleation of water droplets in the atmosphere after
the air becomes supersaturated with water vapor. Aerosols inside clouds are captured in droplets
and rainout occurs. This in-cloud scavenging of particulates is a result of diffusion, interception,
and impaction. When precipitation begins to fall from clouds, the droplets sweep out smaller
particles and gas-phase POMs during their fall toward the ground. This process, termed washout
or below-cloud scavenging, is believed to be significant in removing many pollutants, including
POM, from the atmosphere.
The atmospheric half-life (time required for half the material to be removed or
destroyed) of POM as a class is estimated to be approximately 100 to 1,000 hours under dry
conditions for particulate-bound POM (Esmen and Com, 1971). Studies of urban aerosols in
Pittsburgh, Pennsylvania demonstrated residence times, without precipitation, of from 4 to
40 days for particles less than I /urn in diameter and 0.4 to 4 days for particles 1 to 10 //m in
diameter. Under precipitation conditions, these times are believed to be somewhat shorter.
Studies in Brazil found that under prevailing meteorological and atmospheric conditions, half-life
times of 3 days for benzo(a)pyrene and 12.4 days for perylene were typical (Miguel, 1983).
Some of the highly reactive POM compounds are degraded in the atmosphere by
reactions with oxidants and by photooxidation (Fox and Olive, 1979). Chemical reactivity of
different POM species in the atmosphere may lead to shorter half-lives. Chemical reactivity in
the presence of sunlight may lead to transition of POM adsorbed on soot to other material in
several hours. A number of different types of POM reactions which occur in the atmosphere and
which may affect atmospheric persistence are described in the following sections.
3-20
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Reactions with Molecular Oxygen
Gas-particle interaction between molecular oxygen and several POMs in the
absence of irradiation appears to be very slow. Long range transport of POM has been reported
in the Nordic countries. In the absence of, or under irradiation with low-intensity light, little
evidence for degradation of adsorbed PAH has been shown. However, substantial evidence has
been found for photochemical transformation of POM adsorbed on a variety of solids. The
photosensitivity of adsorbed PAH is strongly dependent on the nature of the surface on which the
compound is adsorbed. A study by Taskar et al. has shown differences in the reaction of pyrene
when adsorbed on carbon, silica, and alumina. The half-lives for the degradation of pyrene
adsorbed on the three types of particles were similar when in the presence of light. In the dark,
however, the half-life of pyrene was approximately twice as long as in light for both silica-bound
pyrene and alumina-bound pyrene, but no difference was observed for carbon-bound pyrene
(Taskar et al., 1985).
A study by Inscoe compared the photo modification of 15 different PAHs,
deposited on 4 different adsorbents (silica gel, alumina, cellulose, and acetylated cellulose),
under exposure to actinic ultraviolet light and room light (Inscoe, 1964). Four of the PAHs did
not react under any of the test conditions (chrysene, phenanthrene, picene, and triphenylene).
The other 11 PAH compounds underwent pronounced changes when adsorbed on silica gel and
alumina. On the less polar substrates of cellulose and acetylated cellulose, transformations of
PAHs were observed but were less extensive and developed more slowly.
Other studies have shown that PAHs adsorbed onto coal fly ash are generally
stabilized against photochemical oxidation by comparison with the same compounds present in
solution, as the pure solid, or adsorbed onto substrates such as alumina or silica gel
(Korfmacher et al., 1979; Korfmacher et al., 1980). This effect has been explained by the
hypothesis that the energetic adsorption of PAH onto a highly active surface, such as that of coal
fly ash or activated carbon, effectively stabilizes PAH against photooxidation which either
increases the electronic excitation energy or decreases the lifetime of the excited state.
3-21
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Reactions with Ozone
Degradation studies of PAH in solution exposed to ozone may not be relevant to
the determination of their half-life on atmospheric particles. Irradiation does not seem to
significantly affect the reactivity of PAHs exposed to ozone (Bjorseth and Olufsen, 1983).
Studies have shown an inverse relationship between the half-life of benzo(a)pyrene and the
measured ambient ozone concentrations (Lane and Katz, 1977). Table 3-3 shows the half-lives
of three POM species in simulated daylight subjected to varying concentrations of ozone. It can
be seen that as ozone levels increase, the half-lives of each species decrease.
Studies of various PAH compounds adsorbed onto diesel exhaust particulate
matter and exposed to ozone have approximated half-lives on the order of 0.5 to 1 hour for most
PAHs measured. This high reactivity of PAH toward ozone on a natural carbonaceous matrix is
probably related to the large specific surface of diesel soot particles as well as to its high
adsorptive capacity for several gaseous compounds. Experiments also indicate significant
conversion at lower, nearly ambient ozone levels. Eisenberg et al. have shown that PAHs on
particulate surfaces are oxidized by low levels of singlet oxygen generated under environmental
conditions (Eisenberg et al., 1985).
Other Reactions
Two types of free radical processes may be important for particulate organic
matter: the gas-particle interactions between hydroxide radicals from the gas phase and
particle-associated PAH, or a direct interaction of organic free radicals present at the particle
surface. The larger PAHs are extremely sensitive to electrophilic substitution and to oxidation.
Nitrogen oxides or dilute nitric acid can either add to, substitute in, or oxidize polycyclic
aromatic hydrocarbons. Transformation of some PAHs to nitro-PAH has been observed in
experiments using relatively low concentrations of nitrogen dioxide and nitric acid (Pitts et al.,
1978; Nielsen, 1984). The reactions appear to be electrophilic, as electron-donating substituents
enhance the reactivity and electron-attracting substituents diminish it. Similar reactions of PAH
3-22
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TABLE 3-3. HALF LIVES IN HOURS OF SELECTED POM IN SIMULATED
DAYLIGHT," SUBJECTED TO VARYING CONCENTRATIONS
OF ATMOSPHERIC OXIDANTS (OZONE)
Ozone (ppm)
0.0
0.19
0.70
2.28
Benzo(k)fluoranthene
14.1
3.9
3.1
0.9
Benzo(a)pyrene
5.3
0.58
0.20
0.08
Benzo(b)fluoranthene
8.7
4.2
3.6
1.9
"Quartzline lamp.
Source: Laneetal., 1977.
3-23
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with atmospheric sulfur dioxide, sulfur trioxide, and sulfuric acid have also been observed
(Tebbens et al., 1966).
3-24
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SECTION 3.0 REFERENCES
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Katz, M., and R. C. Pierce. "Quantitative Distribution of Polynuclear Aromatic Hydrocarbons in
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Loening, K. L., and J. E. Merritt. "Some Aids for Naming Polycyclic Aromatic Hydrocarbons
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Natusch, D.F.S. Formation and Transformation of Paniculate POM Emitted from Coal-fired
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Sonnichsen, T.W. Measurements of POM Emissions from Coal-fired Utility Boilers. EPRI
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Mechanisms. Methods, and Metabolism. Proceedings of the Eighth International Symposium on
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Thomas, J. F., M. Mukai, and B. D. Tebbens. "Fate of Airborne Benzo(a)pyrene." In:
Environmental Science and Technology. 2(l):33-39. 1968.
Toqan, M., J.M. Beer, J.B. Howard, W. Farmayan, and W. Rovesti. "Soot and PAH in Coal
Liquid Fuel Furnace Flames." In: Polynuclear Aromatic Hydrocarbons: Formation.
Mechanisms, and Measurement. Proceedings of the Seventh International Symposium on
Polynuclear Aromatic Hydrocarbons, Columbus, Ohio, 1982. M. Cooke and A. Dennis, eds.
Battelle Press, Columbus, Ohio. pp. 1,205-1,219. 1983.
Tucker, S. P. "Analyses of Coke Oven Effluents for Polynuclear Aromatic Compounds." In:
Analytical Methods for Coal and Coal Products. Volume n, Chapter 43, pp. 163-169. 1979.
U.S. Environmental Protection Agency. Provisional Guidance for Quantitative Risk Assessment
of Polycyclic Aromatic Hydrocarbons. Office of Research and Development. Washington, D.C.
EPA-600/R-93-089. July 1993.
U.S. Environmental Protection Agency. Second Supplement to Compendium of Methods for the
Determination of Toxic Organic Compounds in Ambient Air. Atmospheric Research and
Exposure Assessment Laboratory. Research Triangle Park, North Carolina. EPA-600/4-89-018.
pp. TO-13toTO-97. 1988.
U.S. Environmental Protection Agency. POM Source and Ambient Concentration Data: Review
and Analysis. Washington, DC. EPA Report No. 600/7-80-044. March 1980.
U.S. Environmental Protection Agency. Health Assessment Document for Polycyclic Organic
Matter. External Review Draft. Research Triangle Park, North Carolina. EPA Report
No. 2/102. pp. 3-1 to 3-47. 1978.
U.S. Environmental Protection Agency. Scientific and Technical Assessment Report on
Paniculate Polycyclic Organic Matter (PPOMX Washington, DC. EPA Report
No. 600/6-75-001. March 1975.
3-28
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Van Cauwenberghe, K. A. "Atmospheric Reactions of PAH." In: Handbook of Polycyclic
Aromatic Hydrocarbons: Emission Sources and Recent Progress in Analytical Chemistry.
A. Bjorseth and T. Rambahl, eds. Marcel Dekker, Inc. Volume 2, pp. 351-369. 1985.
Van Noort, P.C.M., andE. Wondergem. Scavenging of Airborne Polycyclic Aromatic
Hydrocarbons by Rain. Environmental Science and Technology. 19(11): 1044-1049. 1985.
Yokley, R. A., A. A. Garrison, E.L. Wehry, and G. Mamantov. Photochemical Transformation
of Pyrene and Benzo(a)pyrene Vapor-Deposited on Eight Coal Stack Ashes. Environmental
Science and Technology. 20(1):86-90. 1986.
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SECTION 4.0
POM EMISSION SOURCE CATEGORIES
This section contains the process descriptions, available emission factor data, and
source locations for source categories of POM emissions. Many of the source categories
discussed in this section emit POM from the fuel combustion process; however, some of the
categories have very unique processes due to the fuel type burned or the type of combustion unit
used.
There are few emission controls that are dedicated solely to reduce POM
emissions, and therefore there are limited data on the effectiveness of control strategies in
reducing POM emissions. Where there are known emission control strategies that may affect
POM emissions from a source category, these are discussed as part of the process description.
Also, in many cases, there are emission factor data provided for both controlled and uncontrolled
units that may be used within a source category.
4.1 STATIONARY EXTERNAL COMBUSTION
The combustion of solid, liquid, and gaseous fuels such as coal, lignite, wood,
bagasse, fuel oil, and natural gas has been shown through numerous tests to be a source of POM
emissions. Polycyclic organic compounds are formed in these sources as products of incomplete
combustion. The rates of POM formation and emissions are dependent on both fuel
characteristics and combustion process characteristics. Emissions of POM can originate from
POM compounds contained in fuels that are released during combustion or from high-
temperature transformations of organic compounds in the combustion zone (Shih et al., 1980;
National Research Council, 1972; National Research Council, 1983).
An important fuel characteristic that affects POM formation in combustion
sources is the carbon-to-hydrogen rado and the molecular structure of the fuel (Shih et al., 1980).
In general, the higher the carbon-to-hydrogen ratio, the greater the probability of POM compound
4-1
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formation. Holding other combustion variables constant, the tendency for hydrocarbons present
in a fuel to form POM compounds is as follows:
aromatics > cycloolefins > olefins > paraffins
Based on both carbon-to-hydrogen ratio and molecular structure considerations, the tendency for
the combustion of various fuels to form POM compounds is as follows: (Shih et al., 1980)
coal > lignite > wood > waste oil > residual oil > distillate oil
These general tendencies may not hold true for every scenario because other combustion
characteristics, such as equipment operation and maintenance, also affect POM emissions.
The primary combustion process characteristics affecting POM compound
formation and emissions are: (Shih et al., 1980; Barrett et al., 1983)
• Combustion zone temperature;
• Residence time in the combustion zones;
• Turbulence or mixing efficiency between air and fuel;
• Air-to-fuel ratio; and
• Fuel feed size.
Concentrations of PAH have been shown to decrease rapidly with increasing
temperature (Shih et al., 1980). The degree to which these process variables can be controlled
varies from source to source; however, larger combustion sources, such as utilities and industrial
boilers, generally have more monitoring devices and mechanisms for adjusting these variables in
order to maximize combustion efficiency. Small commercial units and residential sources
typically are more variable in their combustion efficiency because the operator is limited by the
unit design in making any specific adjustments.
4-2
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The main cause of incomplete fuel combustion is insufficient mixing of air, fuel,
and combustion products. Mixing is a function of operating practices and fuel-firing
configuration. Hand- and stoker-fired solid fuel combustion sources generally exhibit very poor
air and fuel mixing relative to other types of combustion sources. Liquid fuel units and
pulverized solid fuel units provide good air and fuel mixing (Shih et al., 1980; Kelly, 1983;
Barrett et al., 1983).
The air-to-fuel ratio present in the combustion environment is important in POM
formation because certain quantities of air (i.e., oxygen) are needed to stoichiometrically carry
out complete combustion. Air supply is particularly important in systems with poor air and fuel
mixing. Combustion environments with a poor air supply will generally have lower combustion
temperatures and will not be capable of completely oxidizing all the fuel. Systems that
experience frequent startups and shutdowns will also have poor air-to-fuel ratios. Unbumed
hydrocarbons, many as POM compounds, can exist in such systems and eventually be emitted
through the source stack. Generally, stoker and hand-fired solid fuel combustion sources have
problems with insufficient air supply and tend to generate relatively large quantities of POM as a
result (Shih et al., 1980; Kelly, 1983; Barrett et al., 1983).
In solid and liquid fuel combustion sources, fuel feed size can influence
combustion rate and efficiency; therefore, POM compound formation is affected. For liquid fuel
oils, a poor initial fuel droplet size distribution is conducive to poor combustion conditions and
an enhanced probability of POM formation. In most cases, fuel droplet size distribution is
primarily influenced by fuel viscosity. As fuel viscosity increases, the efficiency of atomization
decreases and the droplet size distribution shifts to the direction of larger diameters. Therefore,
distillate oils are more readily atomized than residual oils and result in finer droplet size
distribution. This behavior, combined with the lower carbon-to-hydrogen ratio of distillate oil,
means that residual oil sources inherently have a higher probability of POM formation and
emissions than distillate oil sources (Shih et al., 1980; Kelly, 1983).
For solid fuels, fuel size affects POM formation by significantly impacting
combustion rate. Solid fuel combustion involves a series of repeated steps, each with the
4-3
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potential to form POM compounds. First, the volatile components near the surface of a fuel
particle are burned, followed by burning of the residual solid structure. As fresh, unreacted solid
material is exposed, the process is repeated. Thus, the larger the fuel particle, the greater the
number of times this sequence is repeated and the longer the residence time required to complete
the combustion process. With succeeding repetitions, the greater the probability of incomplete
combustion and POM formation. Stoker and hand-fired solid fuel combustion units represent the
greatest potential for POM emissions due to fuel size considerations (Shih et al., 1980).
POM can be emitted from fuel combustion sources in both a gaseous and a
particulate phase. The compounds are initially formed as gases, but as the flue gas stream cools,
a portion of the POM constituents adsorb to solid fly ash particles present in the stream. The rate
of adsorption is dependent on temperature and fly ash and POM compound characteristics. At
temperatures above 302°F (150°C), most POM compounds are expected to exist primarily in
gaseous form. In several types of fuel combustion systems, it has been shown that POM
compounds are preferentially adsorbed to smaller (submicron) fly ash particles because of their
larger surface area-to-mass ratios. These behavioral characteristics of POM emissions are
important in designing and assessing POM emission control systems (Shih et al., 1980;
Kelly, 1983; Griest and Guerin, 1979; Sonnichsen, 1983).
The primary stationary combustion sources emitting POM compounds are boilers,
furnaces, heaters, stoves, and fireplaces used to generate heat and/or power in the residential,
utility, industrial, and commercial use sectors. A description of the combustion sources, typical
emission control equipment, and POM emission factors for each of these major use sectors is
provided in the sections that follow.
4-4
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SECTION 4.1 REFERENCES
Barrett, W.J. et al. Planning Studies for Measurement of Chemical Emissions in Stack Gases of
Coal-fired Power Plants. Electric Power Research Institute, Palo Alto, California. EPRI Report
No.EA-2892. 1983.
Griest, W.H., and M.R. Guerin.. Identification and Quantification of Polynuclear Organic Matter
(POM) on Participates from a Coal-fired Power Plant. Electric Power Research Institute, Palo
Alto, California. EPRI Report No. EA-1092. 1979.
Kelly, M.E. Sources and Emissions of Polycyclic Organic Matter. U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina. EPA Report No. 450/5-83-01 Ob.
pp. 5-9 to 5-44. 1983.
National Research Council. Polycyclic Aromatic Hydrocarbons: Evaluation of Sources and
Effects. Committee on Pyrene and Selected Analogues, Board on Toxicology and Environmental
Health Hazards, Commission on Life Sciences, National Academy Press, Washington, DC.
1983.
National Research Council. Particulate Polycyclic Organic Matter. Committee on Biologic
Effects of Atmospheric Pollutants, Division of Medical Sciences, National Academy of Sciences,
Washington, DC. 1972.
Shin, C. et al. "POM Emissions from Stationary Conventional Combustion Processes, with
Emphasis on Polychlorinated Compounds of Dibenzo-p-dioxin (PCDDs), Biphenyl (PCBs), and
Dibenzofuran (DCDFs)." CCEA Issue Paper presented under EPA Contract No. 68-02-3138.
U.S. Environmental Protection Agency, Industrial Environmental Research Laboratory, Research
Triangle Park, North Carolina. January 1980.
Sonnichsen, T.W. Measurements of POM Emissions from Coal-Fired Utility Boilers. Electric
Power Research Institute, Palo Alto, California. EPRI Report No. CS-2885. 1983.
4-5
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4.1.1 Residential Heating
The residential sector includes furnaces and boilers burning coal, oil, and natural
gas; stoves and fireplaces burning wood; and kerosene heaters. All of these units are designed to
heat individual homes. Residential combustion sources are generally not equipped with
particulate matter (PM) or gaseous pollutant control devices. In coal- and wood-fired sources,
stove design and operating practice changes have been made to lower PM, hydrocarbon, and
carbon monoxide (CO) emissions. Changes include modified combustion air flow control, better
thermal control and heat storage, and the use of combustion catalysts. Such changes can
conceivably lead to reduced POM formation and emissions (Mead et ah, 1986; Kelly, 1983).
Process Description—Residential Wood'Combustion
Residential wood combustion generally occurs in either a stove or fireplace unit
located inside a house. PAH emissions from wood combustion in residential heating units result
from the combination of free radical species formed in the flame zone, primarily as the result of
incomplete combustion. These emissions can vary widely depending on how the units are
operated and the how the emissions are measured. The following factors will affect PAH
emissions measured from residential wood combustion sources (Johnson et ah, 1990a):
• Unit design and degree of excess air;
• Wood type, moisture content, and other wood characteristics;
• Bum rate and stage of burn;
• Firebox and chimney temperatures; and
• Sampling and analytical methods.
The following discussions describe the specific characterization of wood-fired stoves
(woodstoves) and fireplaces.
4-6
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Woodstoves are commonly used in residences as space heaters. They are used
both as the primary source of residential heat and to supplement conventional heating systems.
Woodstoves have varying designs based on the use or non-use of baffles and catalysts, the extent
of combustion chamber sealing, and differences in air intake and exhaust systems. Woodstove
design and operation practices are important determinants of POM formation in wood-fired
sources (Mead et al., 1986; Kelly, 1983).
The EPA has identified five categories of wood-burning devices based on
differences in both the magnitude and the composition of the emissions (U.S. EPA, 1993b):
• Conventional woodstoves;
• Noncatalytic woodstoves;
• Catalytic woodstoves;
• Pellet stoves; and
• Masonry heaters.
Among these categories, there are many variations in device design and operation characteristics.
The conventional woodstove category comprises all stoves without catalytic
combustors not included in the other noncatalytic categories (i.e., noncatalytic and pellet).
Conventional woodstoves do not have any emissions reduction technology or design features
and, in most cases, were manufactured before July 1, 1986. Stoves of many different airflow
designs may be included in this category, such as updraft, downdraft, crossdraft and S-flow
(U.S. EPA, 1993b).
Noncatalytic woodstoves are those units that do not employ catalysts but do have
emissions-reducing technology or features. The typical noncatalytic design includes baffles and
secondary combustion chambers (U.S. EPA, 1993b).
4-7
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Catalytic woodstoves are equipped with a ceramic or metal honeycomb device,
called a combustor or converter, that is coated with a noble metal such as platinum or palladium.
The catalyst reduces the ignition temperature of the unbumed VOC and CO in the exhaust gases,
thus augmenting their ignition and combustion at normal stove operating temperatures. As these
components of the gases bum, the temperature inside the* catalyst increases to a point at which
the ignition of the gases is essentially self-sustaining (U.S. EPA, 1993b).
Pellet stoves are fueled with pellets of sawdust, wood products, and other biomass
materials pressed into manageable shapes and sizes. These stoves have active air flow systems
and a unique grate design to accommodate this type of fuel. Some pellet stove models are
subject to the 1988 New Source Performance Standards (NSPS); others are exempt because of
their high air-to-fuel ratio (i.e., greater than 35-to-l) (U.S. EPA, 1993b).
The quantities and types of emissions from woodstoves are highly variable,
depending on a number of factors such as stage of the combustion cycle and wood type.
McCrillis and Watts concluded from emissions testing done on three woodstoves that increasing
the burn rate (in terms of mass of wood burned per hour) resulted in increasing PAH emissions
(in terms of mass of pollutant emitted per hour) (McCrillis and Watts, 1992a). Results from
14 tests conducted on conventional and catalytic woodstoves showed a similar trend of
increasing PAH emissions with increasing burn rate (Burnet et al., 1990a).
Regarding wood type, McCrillis and Watts reported that PAH emissions were
higher for stoves burning pine wood as compared to oak wood (McCrillis and Watts, 1992a).
The same conclusion was drawn by Burnet et al., who statistically showed a main effect decrease
in PAH emissions of 849 mg per hour, at a 99-percent confidence bound, in going from pine fuel
to oak fuel (Burnet et al., 1990b).
Fireplaces are used primarily for aesthetic effects and secondarily as a
supplemental heating source in houses and other dwellings. Wood is the most common fuel for
fireplaces, but coal and densified wood "logs" may also be burned (U.S. EPA, 1993a). The user
intermittently adds fuel to the fire by hand. Fireplaces are inefficient combustion devices, with
4-8
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high uncontrolled excess air rates and no sort of secondary combustion. POM emissions result
from the combination of free radical species formed in the flame zone, primarily as a
consequence of incomplete combustion. Under reducing conditions, radical chain propagation is
enhanced, allowing the buildup of complex organic material such as POM. The POM is
generally found in or on smoke particles, although some sublimation into the vapor phase is
probable.
Fireplace heating efficiency may be improved by a number of measures that either
reduce the excess air rate or transfer back into the residence some of the heat that would normally
be lost in the exhaust gases or through fireplace walls. As noted below, such measures are
commonly incorporated into prefabricated units. As a result, the energy efficiencies of
prefabricated fireplaces are slightly higher than those of masonry fireplaces (U.S. EPA, 1993a).
Prefabricated fireplaces are commonly equipped with louvers and glass doors to
reduce the intake of combustion air, and some are surrounded by ducts through which floor-level
air is drawn by natural convection, heated, and returned to the room. Many varieties of
prefabricated fireplaces are now on the market. One general class is the free-standing fireplace,
the most common of which consists of an inverted sheet metal funnel and stovepipe directly
above the fire bed. Another class is the "zero clearance" fireplace, an iron or heavy-gauge steel
firebox lined with firebrick and surrounded by multiple steel walls with spaces for air circulation.
Some zero clearance fireplaces can be inserted into existing masonry fireplace openings, and thus
are sometimes called "inserts." Some of these units are equipped with close-fitting doors and
have operating and combustion characteristics similar to those of woodstoves (U.S. EPA, 1993a).
Emission Factors-Residential Wood Combustion
POM is an important component of the condensible fraction of wood smoke. The
POM in wood smoke contains a wide range of compounds, including organic compounds formed
through incomplete combustion by the combination of free radical species in the flame zone.
Emission factors for conventional, noncatalytic, catalytic, and exempt pellet woodstoves were
compiled from various testing studies and reported by EPA (U.S. EPA, 1993b). The emission
4-9
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factors are shown in Tables 4.1-1 through 4.1-4. No factors are reported for masonry heaters;
however, it is probable that POM is emitted from these units as well.
There are fewer PAH emissions test data for fireplaces as compared to
woodstoves. Factors for individual PAH species from the burning of oak and the burning of pine
were obtained from the results of EPA's research program for controlling residential wood
combustion emissions (Hall and DeAngelis, 1980). As part of that program, PAH emissions
from fireplaces burning seasoned oak wood and green pine were measured. The emission factors
developed from these measurements are shown in Table 4.1-5. Another set of emission factors
collected as part of a literature review by Cooper (Cooper, 1980) is also shown in Table 4.1-5.
The wood type used in the tests supporting those factors was not identified.
Process Description—Residential Coal Combustion
Coal is not a widely used source of fuel for residential heating purposes in the
United States. Only 0.3 percent of the total coal consumption in 1990 was for residential use
(Energy Information Administration, 1992). However, combustion units burning coal are
sources of POM emissions and may be important local sources in areas that have a large number
of residential houses that rely on this fuel for heating.
There are a wide variety of coal-burning stoves in use. These include boilers,
furnaces, stoves that are designed to burn coal, and wood-burning stoves that burn coal. These
units may be hand-fed or automatic feed. Boilers and warm-air furnaces are usually stoker-fed
and are automatically controlled by a thermostat. The stove units are less sophisticated, generally
hand-fed, and less energy efficient than boilers and furnaces. POM emissions from all these
units depend strongly on combustion efficiency, which can vary widely from unit to unit. Higher
POM emissions are typically associated with the stove-type units because they have lower
combustion efficiencies (DeAngelis and Reznik, 1979).
4-10
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TABLE 4.1 1. PAH EMISSION FACTORS FOR CONVENTIONAL WOODSTOVES
SCC Number Emission Source Control Device Pollutant
21-04-008-051 Conventional Woodstove None Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
lndeno( 1 ,2,3-cd)pyrene
Acenaphthylene
Acenaphthene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Average Emission
Factor in Ib/ton
(g/kg)a
0.020
(0.010)
0.004
(0.002)
0.006
(0.003)
0.002
(0.001)
0.012
(0.006)
0.000
(0.000)
0.000
(0.000)
0.212
(0.106)
0.010
(0.005)
0.014
(0.007)
0.004
(0.002)
0.020
(0.010)
Emission
Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.1-1. (Continued)
SCC Number Emission Source Control Device Pollutant
21-04-008-051 Conventional Woodstove None Fluorene
(continued) (continued)
Naphthalene
Phenanthrene
Pyrene
Benzo(e)pyrene
t"
Average Emission
Factor in Ib/ton
(g/kg)a
0.024
(0.012)
0.288
(0.144)
0.078
(0.039)
0.024
(0.012)
0.012
(0.006)
Emission
Factor Rating
E
E
E
E
E
"Factors are expressed as Ib (g) of pollutant emitted per ton (kg) of wood combusted.
Source: U.S. EPA, 1993b.
-------
TABLE 4.1-2. PAH EMISSION FACTORS FOR NONCATALYTIC WOODSTOVES
u>
SCC Number Emission Source Control Device Pollutant
21-04-008-050 Noncatalytic Woodstove Baffles and Secondary Benz(a)anthracene
Combustion Chambers
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthylene
Acenaphthene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Average Emission
Factor in Ib/ton
(g/kgV
<0.001
(<0.001)
0.006
(0.003)
0.004
(0.002)
<0.001
(<0.001)
0.010
(0.005)
0.004
(0.002)
0.020
(0.010)
0.032
(0.016)
0.010
(0.005)
0.009
(0.004)
0.020
(0.010)
0.008
(0.004)
Emission Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.1-2. (Continued)
SCC Number Emission Source Control Device Pollutant
21-04-008-050 Noncatalytic Woodstove Baffles and Secondary Fluorene
(continued) (continued) Combustion Chambers
(continued)
Naphthalene
Phenanthrene
Pyrene
Benzo(e)pyrene
Benzo(ghi)fluoranthene
Perylene
Biphenyl
7 , 1 2-Dimethylbenz(a)anthracene
9-Methylanthracene
1 2-Methylbenz(a)anthracene
3-Methylchloanthrene
Average Emission
Factor in Ib/ton
(g/kg)a
0.014
(0.007)
0.144
(0.072)
0.118
(0.059)
0.008
(0.004)
0.002
(0.001)
0.028
(0.014)
0.002
(0.001)
0.022
(0.011)
0.004
(0.002)
0.004
(0.002)
0.002
(0.001)
<0.001
(<0.001)
Emission Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.1-2. (Continued)
SCC Number Emission Source
21-04-008-050 Noncatalytic Woodstove
(continued) (continued)
Control Device
Baffles and Secondary
Combustion Chambers
(continued)
Pollutant
1 -Methylphenanthrene
Nitronaphthalene
Phenanthrol
Average Emission
Factor in Ib/ton
(g/kg)a
0.030
(0.015)
0.000
(0.000)
0.000
(0.000)
Emission Factor
Rating
E
E
E
"Factors are expressed as Ib (g) of pollutant emitted per ton (kg) of wood combusted.
Source: U.S. EPA, 1993b.
Ui
-------
TABLE 4.1 -3. PAH EMISSION FACTORS FOR CATALYTIC WOODSTOVES
SCC Number Emission Source Control Device Pollutant
21-04-008-030 Catalytic Woodstove Catalytic Converter Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthylene
Acenaphthene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Average Emission
Factor in Ib/ton
fe/ktf
0.024
(0.012)
0.004
(0.002)
0.004
(0.002)
0.002
(0.001)
0.010
(0.005)
0.002
(0.001)
0.004
(0.002)
0.068
(0.034)
0.006
(0.003)
0.008
(0.004)
0.002
(0.001)
0.012
(0.006)
Emission
Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.1 -3. (Continued)
SCC Number Emission Source
21-04-008-030 Catalytic Woodstove
(continued) (continued)
Control Device Pollutant
Catalytic Converter Fluorene
(continued)
Naphthalene
Phenanthrene
Pyrene
Benzo(e)pyrene
Benzo(ghi)fluoranthene
Average Emission
Factor in Ib/ton
(g/kg)1
0.014
(0.007)
0.186
(0.093)
0.489
(0.024)
0.010
(0.005)
0.004
(0.002)
0.006
(0.003)
Emission
Factor Rating
E
E
E
E
E
E
"Factors are expressed as Ib (g) of pollutant emitted per ton (kg) of wood combusted.
Source: U.S. EPA, 1993b.
-------
TABLE 4.1 -4. PAH EMISSION FACTORS FOR PELLET STOVES
SCC Number Emission Source Control Device Pollutant
21-04-008-030 Pellet Stove None Benzo(b)fluoranthene
Chrysene
Fluoranthene
Phenanthrene
Pyrene
Average Emission Factor in
lb/ton(g/kg)a-b
2.60E-05
(1.30E-05)
7.52E-05
(3.76E-05)
5.48E-05
(2.74E-05)
3.32E-05
(1.66E-05)
4.84E-05
(2.42E-05)
Emission Factor
Rating
E
E
E
E
E
bFactors are expressed as Ib (g) of pollutant emitted per ton (kg) of pellets combusted.
Source: U.S. EPA, 1993b.
-------
TABLE 4.1-5. PAH EMISSION FACTORS FOR FIREPLACES
Control Average Emission
SCC Number Emission Source Device Pollutant Factor in Ib/ton (mg/kg)a
21-04-008-001 Fireplace Burning None Benz(a)anthracene/Chrysene
Seasoned Oak
Benzofluoranthenes
Anthracene/Phenanthrene
Fluoranthene
Benzo(ghi)perylene
Pyrene
Methyl anthracenes,
phenanthrenes
Methyl fluoranthenes, pyrenes
Benzo(ghi)fluoranthene
Benzopyrenes/Perylene
Cyclopenta(cd)pyrene
4.00E-03
(2.00)
4.40E-03
(2.20)
2.28E-02
(11.40)
5.20E-03
(2.60)
2.60E-03
(1.30)
5.20E-03
(2.60)
6.80E-03
(3.40)
4.60E-03
(2.30)
1.80E-03
(0.90)
3.40E-03
(1.70)
2.00E-03
(1.00)
Emission
Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
Reference
Hall et al.
Hall et al.
Hall et al.
Halletal.
Hall et al.
Hall et al.
Hall et al.
Hall et al.
Hall et al.
Hall et al.
Halletal.
, 1980
, 1980
. 1980
, 1980
, 1980
, 1980
, 1980
. 1980
, 1980
, 1980
, 1980
(continued)
-------
TABLE 4.1-5. (Continued)
3
Emission
SCC Number Emission Source
21-04-008-001 Fireplace Burning
(continued) Seasoned Oak
(continued)
21-04-008-001 Fireplace Burning Green
(continued) Pine
Control Average Emission
Device Pollutant Factor in Ib/ton (mg/kg)1
None Benzo(c)phenanthrene
C2-alkyl-anthracenes ,
-phenanthrenes
Cyclopenta-anthracenes,
-phenanthrenes
Methy 1-benzanthracenes ,
-benzphenanthrenes, -chrysenes
C2-alkyl-benzanthracenes-
benzophenanthrenes-chrysenes
Dibenzanthracenes,
-phenanthrenes
Dibenzopyrenes
None Benz(a)anthracene/Chrysene
Benzofluoranthenes
Anthracene/Phenanthrene
Fluoranthene
8.00E-04
(0.40)
2.20E-03
(1.10)
8.00E-04
(0.40)
2.60E-03
(1.30)
1.80E-02
(9.00)
6.00E-04
(0.30)
1.40E-03
(0.70)
2.80E-03
(1.40)
3.20E-03
(1.60)
1.38E-02
(6.90)
3.20E-03
(1.60)
Factor
Rating Reference
E
E
E
E
E
E
E
E
E
E
E
Halletal.,
Halletal.,
Halletal.,
Halletal.,
Halletal.,
Halletal.,
Halletal.,
Halletal.,
Halletal.,
Halletal.,
Halletal.,
1980
1980
1980
1980
1980
1980
1980
1980
1980
1980
1980
(continued)
-------
TABLE 4.1-5. (Continued)
N)
Control Average Emission
SCC Number Emission Source Device Pollutant Factor in Ib/ton (mg/kg)a
21-04-008-001 Fireplace - Burning None Benzo(ghi)perylene
(continued) Green Pine (continued)
Pyrene
Methyl anthracenes,
phenanthrenes
Methyl fluoranthenes, pyrenes
Benzo(ghi)fluoranthene
Benzopyrenes/ Perylene
Cyclopenta(cd)pyrene
Benzo(c)phenanthrene
C2-alkyl-anthracenes,
-phenanthrenes
Cyclopenta-anihracenes,
-phenanthrenes
Methyl-benzanthracenes,
-benzphenanthrenes, -chrysenes
C2-alkyl-benzanthracenes-
benzophenanthrenes-chrysenes
3.00E-03
(1.50)
3.20E-03
(1.60)
1.66E-02
(8.30)
3.20E-03
(1.60)
2.80E-03
(1.40)
2.80E-03
(1.40)
2.80E-03
(1.40)
2.60E-03
(1.30)
2.80E-03
(1.40)
2.80E-03
(1.40)
3.20E-03
(1.60)
2.80E-03
(1.40)
Emission
Factor
Rating Reference
E
E
E
E
E
E
E
E
E
E
E
E
Halletal.,
Halletal.,
Halletal.,
Halletal.,
Halletal.,
Halletal..
Halletal.,
Halletal.,
Halletal.,
Halletal.,
Halletal.,
Halletal..
(continued)
1980
1980
1980
1980
1980
1980
1980
1980
1980
1980
1980
1980
-------
TABLE 4.1 -5. (Continued)
Control
SCC Number Emission Source Device Pollutant
21-04-008-001 Fireplace - Burning None Dibenzanthracenes,
(continued) Green Pine (continued) -phenanthrenes
Dibenzopyrenes
21-04-008-001 Fireplace - Wood Type None Benz(a)anthracene
Unspecified
Benzo(a)pyrene
Benzofluoranthenes
Acenaphthene
Acenaphthylene
Anthracene/Phenanthrene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Average Emission
Factor in Ib/ton (mg/kg)a
l.OOE-04
(0.05)
2.00E-04
(0.10)
3.80E-03
(1.90)
1.46E-03
(0.73)
3.80E-03
(1.90)
2.40E-03
(1.20)
2.00E-02
(10.00)
1.76E-02
(8.80)
2.80E-03
(1.40)
3.20E-03
(1.60)
9.40E-03
(4.70)
Emission
Factor
Rating Reference
E
E
U5
U5
U5
U5
U5
U5
U5
U5
U5
Halletal., 1980
Halletal., 1980
Cooper, 1980
Cooper, 1980
Cooper, 1980
Cooper, 1980
Cooper, 1980
Cooper, 1980
Cooper, 1980
Cooper, 1980
Cooper, 1980
(continued)
-------
TABLE 4.1 -5. (Continued)
SCC Number
21-04-008-001
(continued)
Control
Emission Source Device Pollutant
Fireplace - Wood Type None Pyrene
Unspecified (continued)
Dibenzanthracenes
Average Emission
Factor in Ib/ton (mg/kg)a
3.20E-03
(1.60)
3.60E-04
(0.18)
Emission
Factor
Rating
U5
U5
Reference
Cooper, 1980
Cooper, 1980
'Factors are expressed as ib (mg) of pollutant emitted per ton (kg) of wood combusted.
-------
POM emissions for residential coal combustion also depend on the type of coal
being burned. DeAngelis et al., found that POM emissions increased as volatile content
increased. Other studies report that anthracite coal generated lower POM emissions than
bituminous coal (Giammer et al., 1976; and Sanborn et al., 1985).
Emission Factors—Residential Coal Combustion
DeAngelis and Reznik, reported average POM emission rates for a coal-burning
boiler and furnace. These emission rates, shown in Table 4.1-6, represent the total of both
particulate- and gas-phase POM. Both the boiler and the furnace were burning bituminous coal.
POM emissions were much higher during the "off position of the furnace than during the "on"
position because air flow was reduced during the "off position. They also showed that excess
air flow reduced POM emissions (DeAngelis and Reznik, 1979).
PAH emission factors for residential coal combustion in stoves were reported in
an emissions inventory study of Canada and the northeastern United States
(Johnson et al., 1990b). The emission factors reported in that study were developed from
emissions testing of three woodstoves (Sanborn, 1985). These factors are shown in Table 4.1-7.
The testing was conducted on a coal stove and a woodstove burning both bituminous and
anthracite coal. The factors represent the total of particulate- and gas-phase POM.
Process Description—Residential Distillate Oil Combustion
Distillate oil is the second most important home heating fuel behind natural gas
(McCrillis and Watts, 1992b). The use of distillate oil-fired heating units is concentrated in the
northeastern portion of the United States. In 1991, Connecticut, Maine, Massachusetts, New
Hampshire, Rhode Island, Vermont, Delaware, District of Columbia, Maryland, New Jersey,
New York, and Pennsylvania accounted for approximately 72 percent of the residential share of
distillate oil sales (Energy Information Administration, 1991).
4-24
-------
TABLE 4.1-6. PAH I'MISSION FACTORS FOR RESIDENTIAL COAL BOILERS AND FURNACES
SCC Number Emission Source Control Device Pollutant
21-04-002-000 Bituminous/Subbituminous None Benzopyrenes and Perylene
Coal Boilers and Furnaces
Benzofluoranthene(s)
Chrysene/Benz(a)anthracene
Dibenz(a,h)anthracene
Indeno(l ,2,3-cd)pyrene
Anthracene/Phenanthrene
Fluoranthene
Pyrene
Benzo(c)phenanthrene
7, 12-Dimethylbenz(a)anthracene
9-MethyIanthracene
Dimethylanthracenes, phenanthrenes
Average Emission
Factor in Ib/ton
(g/kg)a
6.01E-03
(3.00E-03)
8.02E-03
(4.00E-03)
8.02E-03
(4.00E-03)
6.01E-03
(3.00E-03)
4.01 E-03
(2.00E-03)
3.21E-02
(1.60E-02)
l.OOE-02
(5.00E-03)
l.OOE-02
(5.00E-03)
4.01E-04
(2.00E-04)
1.66E-01
(8.30E-02)
4.01E-04
(2.00E-04)
1.60E-02
(8.00E-03)
Emission
Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.1-6. (Continued)
SCC Number Emission Source Control Device Pollutant
21-04-002-000 Bituminous/Subbituminous None Methylanthracenes, phenanthrenes
(continued) Coal Boilers and Furnaces
(continued)
3-Methylchloanthrene
Dibenzothiophene
Methylfiuoranthenes, pyrenes
Dibenzo(c,g) carbazole
Dibenzopyrenes
Methylchrysenes
C4-Alkylphenanthrene
Average Emission
Factor in Ib/ton
(g/kg)a
2.00E-02
(l.OOE-02)
4.01E-03
(2.00E-03)
4.01E-04
(2.00E-04)
6.01E-03
(3.00E-03)
0.00
(<0.0001)
1.80E-02
(9.00E-03)
l.OOE-03
(5.00E-03)
4.01E-03
(2.00E-03)
Emission
Factor Rating
E
E
E
E
E
E
E
E
'Factors are expressed as Ib (g) of pollutant emitted per ton (kg) of wood combusted.
Source: DeAngelis and Reznik, 1979.
-------
TABLE 4.1 -7. PAH EMISSION FACTORS FOR RESIDENTIAL COAL STOVES
SCC Number Emission Source Control Device Pollutant
21-04-002-000 Bituminous/Subbituminous Coal None Benz(a)anthracene
Stove
Benzo(a)pyrene
Chrysene
Acenaphthylene
Anthracene
Phenanthrene
Benzo(e)pyrene
21-04-001-000 Anthracite Coal None Benz(a)anthracene
Benzo(a)pyrene
Chrysene
Acenaphthene
Acenaphthylene
Average Emission
Factor in Ib/ton
(mg/Mg)a
6.01E-03
(3,000.00)
5.21E-03
(2.600.00)
5.61E-03
(2.800.00)
2.40E-02
(12.000.00)
6.21E-03
(3.100.00)
2.20E-02
(11,000.00)
4.01E-03
(2,000.00)
7.01E-05
(35.00)
6.41E-06
(3.20)
6.41E-05
(32.00)
2.61E-05
(13.00)
1.18E-04
(59.00)
Emission Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.1-7. (Continued)
oo
SCC Number Emission Source Control Device Pollutant
21-04-001-000 Anthracite Coal None Anthracene
(continued) (continued)
Fluorene
Phenanthrene
Benzo(e)pyrene
Average Emission
Factor in Ib/ton
(mg/Mg)a
2.81E-05
(14.00)
3.01E-05
(15.00)
2.75E-04
(137.00)
7.62E-06
(3.80)
Emission Factor
Rating
E
E
E
E
"Factors are expressed as Ib (mg) of pollutant emitted per ton (Mg) of coal combusted.
Source: Johnson et al., 1990b.
-------
Residential oil-fired heating units are available in a number of design and
operating variations. These variations are related to burner and combustion chamber design,
excess air, heating medium, etc. Residential systems typically operate only in an "on" or "off'
mode and at a constant fuel-firing rate, as opposed to commercial and industrial applications,
where load modulation is used (Suprenant et al., 1979). In distillate oil-fired heating units,
pressure or vaporization is used to atomize fuel oil in an effort to produce finer droplets for
combustion. Finer droplets generally mean more complete combustion and less POM formation.
When properly tuned, residential oil furnaces are relatively clean-burning,
especially as compared to woodstoves (McCrillis and Watts, 1992b). However, Steiber and
McCrillis (1991) have shown that, in practice, not all of the fuel oil is burned and tiny droplets
escape the flame and are carried out in the exhaust. Steiber and McCrillis also concluded that
most of the organic emissions from an oil furnace are due to the unburned oil as opposed to soot
from the combustion process; especially in the more modern burners that use a retention head
burner, where over 90 percent of the carbon in the emissions was from unburned fuel
(Steiber and McCrillis, 1991).
Emission Factors—Residential Distillate Oil Combustion
Emission factors for PAH from distillate oil-fired heating units were compiled as
part of a Canadian inventory study (Johnson et al., 1990b). The factors reported in that study
were derived from two sources: testing of two pressure-atomized and one vaporized unit by
Hagenbrauk (1967) and the results of a literature search (Smith, 1984) which identified emission
factors for one pressure-atomized and one vaporized unit. The factors reported in the
Johnson et al. inventory are shown in Table 4.1-8.
Process Description—Residential Natural Gas Combustion
Natural gas is the fuel most widely used for home heating purposes, with more
than half of all homes being heated through natural gas combustion (Ryan and McCrillis, 1994).
Gas-fired residential heating systems are generally less complex and easier to maintain than
4-29
-------
TABLE 4.1-8. PAH EMISSION FACTORS FOR RESIDENTIAL OIL-FIRED COMBUSTION SOURCES
u>
o
Control
SCC Number Emission Source Device Pollutant
21-04-004-000 Distillate (No. 2 Oil) Oil-Fired Furnaces None Benz(a)anthracene
(average of atomized and vaporized units)
Benzo(a)pyrene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Phenanthrene
Pyrene
Benzo(e)pyrene
Coronene
Perylene
Average Emission Factor in
lb/1000 gal (mg/kL)a
5.44E-04
(65.00)
1.92E-05
(2.30)
ND
5.02E-05
(6.00)
3.93E-03
(470.00)
l.OOE-03
(120.00)
1.42E-03
(170.00)
1.25E-04
(15.00)
3.60E-05
(4.30)
7.53E-06
(0.90)
Emission
Factor
Rating
E
E
E
E
E
E
E
E
E
E
"Factors are expressed as Ib (mg) of pollutant emitted per 1,000 gal (kL) of oil combusted.
ND = not detected.
Source: Johnson et al., 1990b.
-------
oil-burning units because the fuel burns more cleanly and no atomization is required. Most
residential gas burners are typically of the same basic design. Natural aspiration is used where
the primary air mixes with the gas as it passes through the distribution pipes. Secondary air
enters the furnace around the burners. Flue gases then pass through a heat exchanger and a stack.
As with oil-fired systems, there is usually no pollution control equipment installed on gas
systems, and excess air, residence time, flame retention devices, and maintenance are the key
factors in the control of emissions from these units.
Emission Factors-Residential Natural Gas Combustion
Emissions testing for PAH from gas-fired residential units has been extremely
scarce, probably because the expected emissions are low and this source has not been identified
as a priority for testing. Based on emission factors relative to thermal input, Ryan and McCrillis
concluded that residential natural gas emissions are at least a factor of 10 to 100 less than
comparable emissions from residential oil furnaces and woodstoves (Ryan and McCrillis, 1994).
As part of the study quantifiable amounts of specific PAH compounds were measured from two
natural gas, forced-air furnaces and emission factors were developed.
One of the furnaces was a 15 to 20 year old, horizontal forced-air furnace with a
medium efficiency rating of between 60 to 70 percent. The second furnace tested was a new,
modern, high-efficiency furnace with an energy efficiency rating of 94 percent. The units were
configured and operated to match a residential-type setting. Based on their results, the study
team concluded that detection limits for many of the PAH compounds were inadequate to
accurately estimate emission factors for a large majority of the PAH compounds. The team did,
however, report emission factors for a limited number of PAHs that were measured above the
detection limit. These factors are presented in Table 4.1-9.
Process Description—Residential Kerosene Combustion
The sale and use of kerosene space heaters increased dramatically during the
1980s (Traynor et al., 1990). They continue to be sold and used throughout the United States as
4-31
-------
TABLE 4.1-9. PAH EMISSION FACTORS FOR RESIDENTIAL NATURAL
GAS-FIRED COMBUSTION SOURCES
u>
Control
SCC Number Emission Source Device Pollutant
21-04-006-000 Natural Gas-Fired, Horizontal Forced-Air None Benz(a)anthracene
Furnace, Rated at 120,000 Btu/hr
Chrysene
Fluoranthene
Pyrene
21-04-006-000 Modern, High-Efficiency, Natural Gas-Fired, None Benz(a)anthracene
Vertical, Condensing Up-Flow Forced- Air
Furnace Rated at 50,000 Btu/hr
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Indeno(l ,2,3-cd)pyrene
Dibenz(a,h)anthracene
Average Emission
Factor in lb/1012 Btu
(Pg/kJ)a
9.33E-02
(40.00)
3.96E-02
(17.00)
4.90E-02
(21.00)
6.99E-02
(30.00)
1.10E-01
(47.00)
8.39E-02
(36.00)
1.21E-01
(52.00)
1.21E-01
(52.00)
1.21E-01
(52.00)
6.53E-02
(28.00)
4.43E-02
(19.00)
Emission
Factor Rating
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.1-9. (Continued)
u>
u>
SCC Number
21-04-006-000
(continued)
Control
Emission Source Device
Modem, High-Efficiency, Natural Gas-Fired, None
Vertical, Condensing Dp-Flow Forced-Air
Furnace Rated at 50,000 Btu/hr
(continued)
Pollutant
Benzo(ghi)perylene
Average Emission
Factor in lb/1012 Btu
(pg/kJ)1
1.35E-01
(58.00)
Emission
Factor Rating
E
Fluoranthene
Phenanthrene
Pyrene
5.13E-02
(22.00)
9.79E-02
(42.00)
6.53E-02
(28.00)
"Factors are expressed in Ib (pg) of pollutant emitted per 1012 Btu (kJ) of natural gas combusted.
Source: Ryanet al., 1994.
-------
supplementary home heating sources and, in some cases, as primary heating sources. These units
are usually unvented and release emissions inside the home, with some emissions eventually
escaping to the atmosphere. There are two basic types of kerosene space heaters: convective and
radiant.
Emission Factors—Residential Kerosene Combustion
Traynor et al. investigated emissions from both types of kerosene space heaters
(Traynor et al., 1990). Particulate PAH emission rates were developed for a radiant heater
operating under well-tuned conditions and a convective heater operating under poorly tuned
conditions. These emission rates are shown in Table 4.1-10. The study team concluded that
kerosene heaters can emit PAHs and nitrated PAHs. Naphthalene was the primary PAH emitted
from both types of heaters. Relatively few PAHs were observed in this study, but that may be
due to the use of a very broad GC/MS scanning technique; other PAHs would probably have
been found by a more sensitive technique.
4-34
-------
TABLE 4.1-10. PAH EMISSION FACTORS FOR RESIDENTIAL KEROSENE HEATERS
SCC Number Emission Source Control Device Pollutant
21-04-011-000 Radiant Kerosene Space Heater - Well-tuned None Chrysene
Fluoranthene
Naphthalene
Phenanthrene
21-04-011-000 Convective Kerosene Space Heater - Maltuned None Anthracene
Fluoranthene
Naphthalene
Phenanthrene
Average Emission
Factor in
lb/10E+12Btu
(ng/kJ)a
0.02
(0.01)
0.05
(0.02)
18.65
(8.00)
0.70
(0.30)
0.70
(0.30)
0.70
(0.30)
53.62
(23.00)
2.10
(0.90)
Emission Factor
Rating
E
E
E
E
E
E
E
E
"Factors are expressed in Ib (ng) of pollutant emitted per 10E+12 Btu (kJ) of kerosene combusted.
Source: Traynoret al., 1990.
-------
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4-36
-------
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Residential Coal-fired Space Heaters. U.S. Environmental Protection Agency, Research Triangle
Park, North Carolina. EPA/600/D-85/243. 1985.
Smith, I.M. "PAH from Coal Utilization-Emissions and Effects." IEA Coal Research, London,
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Engineering Research Laboratory, Research Triangle Park, North Carolina, pp. 4-6. 1991.
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Conventional Stationary Combustion Systems. Volume 1: Gas- and Oil-Fired Residential
Heating Sources. U.S. Environmental Protection Agency, Industrial Environmental Research
Laboratory, Research Triangle Park, North Carolina, pp. 19-20. 1979.
Traynor, G. W., M. G. Apte, and H. A. Sokol. "Selected Organic Pollutant Emissions from
Unvented Kerosene Space Heaters." Environmental Sciences and Technology, Volume 24,
No. 8, pp. 1265-1270. 1990.
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U.S. Environmental Protection Agency. Supplement F to Compilation of Air Pollutant Emission
Factors. Volume I: Stationary Point and Area Sources. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. AP-42, Volume I, Supplement F. pp. 1.9-1
to 1.9-5. July 1993a.
U.S. Environmental Protection Agency. Supplement F to Compilation of Air Pollutant Emission
Factors. Volume I: Stationary Point and Area Sources. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. AP-42, Volume I, Supplement F. pp. 1.10-1
to 1.10-2. Julyl993b.
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4.1.2 Utility. Industrial and Commercial Fuel Combustion
Process Description—Utility Sector
Utility boilers bum coal, oil, and natural gas to generate steam for electricity
generation. Fossil fuel-fired utility boilers comprise about 72 percent (or 497,000 megawatts
[MW]) of the generating capacity of U.S. electric power plants. Of these fuels, coal is the most
widely used, accounting for 60 percent of the U.S. fossil fuel generating capacity. Natural gas
represents about 25 percent and oil represents 15 percent of the U.S. fossil fuel generating
capacity (U.S. EPA, 1994a).
A utility boiler consists of several major subassemblies, as shown in
Figure 4.1.2-1. These subassemblies include the fuel preparation system, air supply system,
burners, the furnace, and the convective heat transfer system. The fuel preparation system, air
supply, and burners are primarily involved in converting fuel into thermal energy in the form of
hot combustion gases. The furnace and convective heat transfer system are involved in the
transfer of the thermal energy in the combustion gases to the superheated steam required to
operate the steam turbine and produce electricity (U.S. EPA, 1994a).
Three key thermal processes occur in the furnace and convective sections of the
boiler. First, thermal energy is released during controlled mixing and combustion of fuel and
oxygen in the burners and furnace. Second, a portion of the thermal energy formed by
combustion is adsorbed as radiant energy by the furnace walls. The furnace walls are formed by
multiple, closely-spaced tubes, which carry high-pressure water from the bottom of the furnace to
absorb radiant heat energy to the steam drum located at the top of the boiler. Third, the gases
enter the convective pass of the boiler, and the balance of the energy retained by the
high-temperature gases is adsorbed as convective energy by the convective heat transfer system
(superheater, reheater, economizer, and air preheater) (U.S. EPA, 1994a).
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Superhaateri and Reheatert
Furnace
Burner
Zone
Secondary Air
Burners
•
3
U.
3
t
g
fr
V
Fuel Prep
Flue Gas
Air
Fuel
Figure 4.1.2-1. Simplified Boiler Schematic
Source: U.S. EPA, 199a.
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Utility boilers are generally identified by their furnace configuration. Different
furnace configurations used in utility boilers include tangentially-fired, wall-fired, cyclone-fired,
stoker-fired, and fluidized bed combustion (FBC) boilers. Some of these furnace configurations
are designed primarily for coal combustion, while others are designed for coal, oil, or natural gas
combustion. The types of furnaces most commonly used for firing oil and natural gas are the
tangentially-fired and wall-fired boiler designs (Shih et al., 1980). One of the primary
differences between furnaces designed to burn coal versus oil or gas is the furnace size. Coal
requires the largest furnace, followed by oil, then gas (U.S. EPA, 1994a).
The average size of boilers used in the utility sector varies primarily according to
boiler type. Cyclone-fired boilers are generally the largest, averaging about 250 to 380 MW
generating capacity. Tangentially-fired and wall-fired boiler designs firing coal average about
120 to 430 MW, while these designs firing oil and natural gas average about 100 to 270 MW.
Stoker-fired boilers average about 10 to 17 MW (Shih et al., 1980). Additionally, unit sizes of
FBC boilers range from 25 to 400 MW, with the largest FBC boilers typically closer to 200 MW
(U.S. EPA, 1994a).
Tangentially-fired Boiler-The tangentially-fired boiler is based on the concept of a single flame
zone within the furnace. The fuel-air mixture in a tangentially-fired boiler projects from the four
corners of the furnace along a line tangential to an imaginary cylinder located along the furnace
centerline. When coal is used as the fuel, the coal is pulverized in a mill to the consistency of
talcum powder (i.e., at least 70 percent of the particles will pass through a 200 mesh sieve),
entrained in primary air, and fired in suspension (U.S. EPA, 1995a). As fuel and air are fed to
the burners, a rotating "fireball" is formed, which may be moved up and down by tilting the
fuel-air nozzle assembly, to control the furnace exit gas temperature and provide steam
temperature control during variations in load. Tangentially-fired boilers commonly burn coal
(pulverized). However, oil or gas may also be burned (U.S. EPA, 1994a).
Wall-fired Boiler-Wall-fired boilers are characterized by multiple individual burners located on
a single wall or on opposing walls of the furnace (Figure 4.1.2-2). As with tangential-fired
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Burner B
Burner A
Air A-
AirB-
AirC-
AirD-
FuelA
FuelB
FueIC
FuelD
Burner D
Burner C
Figure 4.1.2-2. Single Wall-Fired Boiler
Source: U.S. EPA, 1994a.
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boilers, when coal is used as the fuel, the coal is pulverized, entrained in primary air, and fired in
suspension. In contrast to tangentially-fired boilers that produce a single flame envelope, or
fireball, each of the burners in a wall-fired boiler has a relatively distinct flame zone. Depending
on the design and location of the burners, wall-fired boilers consist of various designs, including
single-wall, opposed-wall, cell, vertical, arch, and turbo. Wall-fired boilers may burn coal
(pulverized), oil, or natural gas (U.S. EPA, 1994a).
Cyclone-fired Boiler-In cyclone-fired boilers, fuel and air are burned in horizontal, cylindrical
chambers, producing a spinning, high-temperature flame (Figure 4.1.2-3). When coal is used, the
coal is crushed (rather than pulverized) to a 4-mesh size and admitted with the primary air in a
tangential fashion. The finer coal particles are burned in suspension, while the coarser particles
are thrown to the walls by centrifugal force (Shin et al., 1980). Cyclone-fired boilers are almost
exclusively coal-fired. However, some units are also able to fire oil and natural gas
(U.S. EPA, 1994a).
Fluidized Bed Combustion Boiler-Fluidized bed combustion (FBC) is a newer boiler technology
that is not as widely used as the other, conventional boiler types. In a typical FBC boiler, crushed
coal in combination with inert material (sand, silica, alumina, or ash) and/or sorbent (limestone)
is maintained in a highly turbulent suspended state by the upward flow of primary air from the
windbox located directly below the combustion floor (Figure 4.1.2-4). This fluidized state
provides a large amount of surface contact between the air and solid particles, which promotes
uniform and efficient combustion at lower furnace temperatures, 1,575 to 1,650°F (860 to
900°C) compared to 2,500 to 2,800°F (1,370 to 1,540°C) for conventional coal-fired boilers.
Fluidized bed combustion boilers have been developed to operate at both atmospheric and
pressurized conditions (U.S. EPA, 1994a).
Stoker-fired Boiler—Instead of firing coal in suspension, as practiced by the boilers described
above, mechanical stokers can be used to burn coal in fuel beds. All mechanical stokers are
designed to feed coal onto a grate within the furnace. The most common stoker type of boiler
used in the utility industry is the spreader stoker (Figure 4.1.2-5). Other stoker types are
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SECONDARY
AIR INLET
COAL PIPE -
CRUSHED COAL
(1/4* Screen
Plus Primary Ak)
TERTIARY
AIR INLET
Figure 4.1.2-3. Cyclone Burner
SCROLL
BURNER
Source: U.S. EPA, 1994a.
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Flue Gas
Cyclone
Convection ,
Pass
Coal Limestone
\7
Freeboard <
Splash
Zone
Bed
Transport Air
Forced Draft Air
Compressor
Fluldlzlng Air
Recycle
Waste
Waste
Distributor
Plate
Plenum
Figure 4.1.2-4. Simplified Atmospheric Fluidized Bed
Combustor Process Flow Diagram
Source: U.S. EPA, 1994a.
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Tangential Overfire Air
Distributors
Drive Shaft
Grates
Return Rails
Tangential Overfire Air
Drag
Carbon-Recovery Nozzles
Back-Stop Assembly
Take-Up
Siftings Hopper
Figure 4.1.2-5. Spreader Type Stoker-fired Boiler
<9
te
Source: U.S. EPA, 1994a.
-------
overfeed and underfeed stokers. In spreader stokers, a flipping mechanism throws crushed coal
into the overfeed and underfeed stokers. In spreader stokers, a flipping mechanism throws
crushed coal into the furnace and onto a moving fuel bed (grate). Combustion occurs partly in
suspension and partly on the grate (U.S. EPA, 1995a). In overfeed stokers, crushed coal is fed
onto a traveling or vibrating grate from an adjustable gate above and burns on the fuel bed as it
progresses through the furnace. Conversely, in underfeed stokers, crushed coal is forced upward
onto the fuel bed from below by mechanical rams or screw conveyors (U.S. EPA, 1995a;
U.S. EPA, 1994a).
Emission Control Techniques-Utility boilers are highly efficient and generally the best
controlled of all combustion sources. Existing emission regulations for total paniculate matter
(PM), nitrogen oxides (NOX), and sulfur dioxide (SO2) have necessitated controls on coal-, oil-,
and gas-fired utility sources. Oil-fired units are not controlled for SO2 other than by choice of
fuel sulfur content (i.e., no add-on controls for oil). Emission controls for PM and SO2 are not
required on natural gas boilers because uncontrolled emissions are inherently low relative to coal
and oil units (Kelly, 1983). Baghouses, ESPs, wet scrubbers, and multicyclones have been
applied for PM control in the utility sector. Particulate POM, particularly fine particles, would
be controlled most effectively by baghouses or ESPs. No control of gaseous POMs would be
achieved by baghouse and ESP systems. Wet scrubbers could potentially be effective for
controlling particulate and gaseous POM. Scrubbers would condense the POM compounds
existing as vapors and collect them as the gas stream is saturated in the scrubber. Multicyclones
would be the poorest control system for POM emissions because they are ineffective on fine
particles and would offer no reduction of gaseous POM (Mead et al., 1986: Kelly, 1983).
Nitrogen oxide control techniques for utility boilers such as low excess air firing
and staged combustion may act to increase POM compound formation. The principle of these
NOX control techniques is to limit the oxygen available for NOX formation in the combustion
zone. Limiting oxygen effects a lower air/fuel ratio and may cause increased POM formation.
Data to completely characterize the effect of combustion source NOX controls on POM emissions
are very limited and inconsistent (Mead et al., 1986; Kelly, 1983).
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The most common SO2 control technology currently used on utility boilers is
lime/limestone flue gas desulfurization (FGD). This technology employs a wet scrubber for SO2
removal and is often preceded by an ESP, which accomplishes the bulk of PM control. Wet
FGD/ESP systems, while providing for the control of POM condensed on paniculate matter at
the entrance to the ESP, have been shown to poorly control vapor phase POM. Tests examining
benzo(a)pyrene showed that condensation of the vapor phase POM compound would occur in the
scrubber, but significant collection of POM particles remaining in the gas flow through the
scrubber was not achieved (Mead et al., 1986; Kelly, 1983).
A more recently applied SO2 control technique for utility boilers is spray drying.
In this process, the gas stream is cooled in the spray dryer but remains above the saturation
temperature. A fabric filter or an ESP is located downstream of the spray dryer, thus providing
for significant control of both particulate and vapor phase POM because the vapor phase
compounds are condensed before they reach the baghouse or ESP (Mead et al., 1986;
Kelly, 1983).
In general, emissions of organic pollutants, including POM, are reduced by
operating the furnace in such a way as to promote complete combustion of the fossil fuel(s)
combusted in the furnace. Therefore, any combustion modification which increases the
combustion efficiency will most likely reduce POM emissions.
Process Description-Industrial/Commercial Sector
Industrial boilers are widely used in manufacturing, processing, mining, and
refining, primarily to generate process steam, electricity, or space heat at the facility. However,
the industrial generation of electricity is limited, with only 10 to 15 percent of industrial boiler
coal consumption and 5 to 10 percent industrial boiler gas and oil consumption used for
electricity generation (U.S. EPA, 1982). Commercial boilers are used by commercial
establishments, medical institutions, and educational institutions to provide space heating. In
collecting survey data to support its Industrial Combustion Coordinated Rulemaking (ICCR), the
EPA compiled information on a total of 69,494 combustion boiler units in the industrial and
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commercial sectors (U.S. EPA, 1998). While this number likely underestimates the total
population of boilers in the industrial and commercial sectors (due to unreceived survey
responses and lack of information on very small units) it provides an indication of the large
number of sources included in this category.
Of the units included in the ICCR survey database, approximately 70 percent were
classified in the natural gas fuel subcategory, 23 percent in the oil (distillate and residual)
subcategory, and 6 percent in the coal burning subcategory. These fuel subcategory assignments
characterize the market population of boiler units according to their primary fuel burned, and are
based on the units burning only greater than 90 percent of the specified fuel for that subcategory.
All other units (accounting for the other 1 percent of assignments) are assigned to a subcategory
of "other fossil fuel" (U.S. EPA, 1998).
Other fuels burned in industrial boilers are wood wastes, liquified petroleum gas,
asphalt, and kerosene. Of these fuels, wood waste is the only non-fossil fuel discussed here,
since POM emissions were not characterized for combustion of the other fuels. The burning of
wood waste in boilers is mostly confined to those industries where it is available as a by-product.
It is burned both to obtain heat energy and to alleviate possible solid waste disposal problems.
Generally, bark is the major type of waste burned in pulp mills. In the lumber, furniture, and
plywood industries, either a mixture of wood and bark waste or wood waste alone is most
frequently burned. As of 1980, there were approximately 1,600 wood-fired boilers operating in
the United States, with a total capacity of over 30,000 MW (U.S. EPA, 1994b).
Many of the same types of boilers used by the utility sector are also utilized by the
industrial/commercial sector; however, the average boiler size used by the industrial/commercial
sector is substantially smaller. Additionally, a few types of boiler designs are used only by the
industrial/commercial sector. For a general description of the major subassemblies of and key
thermal processes that occur in boilers, refer to Utility Sector process description and
Figures 4.1.2-1 through 4.1.2-5.
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Water-tube Boilers-In water-tube boilers, the water being heated flows through tubes surrounded
by circulating hot gases. Water-tube boilers represent the majority (i.e., 57 percent) of industrial
and commercial boiler capacity (70 percent of industrial boiler capacity) (U.S. EPA, 1982).
Water-tube boilers are used in a variety of applications ranging from supplying large amounts of
process steam to providing space heat for industrial and commercial facilities. These boilers
have capacities ranging from 2.9 MW to 439.5 MW, averaging about 120 MW. The most
common types of water-tube boilers used in the industrial/commercial sector are wall-fired and
stoker-fired boilers. Tangentially-fired and FBC boilers are less commonly used. Refer to Utility
Sector for descriptions of these boiler designs (U.S. EPA, 1979).
Fire-tube and Cast Iron Boilers—The industrial/commercial sector also uses boilers with two
other types of heat transfer methods: fire-tube and cast iron boilers. In fire-tube boilers, the hot
gas flows through the tubes and the water being heated circulates outside of the tubes. Fire-tube
boilers are not available with capacities as large as water-tube boilers, but they are also used to
produce process steam and space heat. Most fire-tube boilers have a capacity 0.4 to 7.3 MW
thermal. Most installed fire-tube boilers burn oil or gas and are used primarily in
commercial/institutional applications (U.S. EPA, 1979).
In cast iron boilers, the hot gas is also contained inside the tubes that are
surrounded by the water being heated, but the units are constructed of cast iron instead of steel.
Cast iron boilers are limited in size and are used only to supply space heat. Cast iron boilers
range in size from less than 0.1 to 2.9 MW thermal (U.S. EPA, 1979).
Wood Waste Boilers—The burning of wood waste in boilers is mostly confined to those
industries where it is available as a by-product. Wood waste is burned both to obtain heat energy
and to alleviate solid waste disposal problems. Wood waste may include large pieces such as
slabs, logs, and bark strips, as well as cuttings, shavings, pellets, and sawdust (U.S. EPA, 1994b).
Various boiler firing configurations are used in burning wood waste. One
common type in smaller operations is the dutch oven or extension type of furnace with a flat
grate. This unit is widely used because it can burn fuels with very high moisture. Fuel is fed into
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the oven through apertures in a firebox and is fired in a cone-shaped pile on a flat grate. The
burning is done in two stages: (1) drying and gasification, and (2) combustion of gaseous
products. The first stage takes place in a cell separated from the boiler section by a bridge wall.
The combustion stage takes place in the main boiler section (U.S. EPA, 1994b).
In another type of boiler, the fuel-cell oven, fuel is dropped onto suspended fixed
grates and is fired in a pile. The fuel cell uses combustion air preheating and positioning of
secondary and tertiary air injection ports to improve boiler efficiency (U.S. EPA, 1994b).
In many large operations, more conventional boilers have been modified to burn
wood waste. The units may include spreader stokers with traveling grates or vibrating grate
stokers, as well as tangentially fired or cyclone-fired boilers (see Utility Sector for descriptions of
these types of boilers). The most widely used of these configurations is the spreader stoker,
which can burn dry or wet wood. Fuel is dropped in front of an air jet, which casts the fuel out
over a moving grate. The burning is done in three stages: (1) drying, (2) distillation and burning
of volatile matter, and (3) burning of fixed carbon. Natural gas or oil is often fired as auxiliary
fuel. This is done to maintain constant steam when the wood supply fluctuates or to provide
more steam than can be generated from the wood supply alone (U.S. EPA, 1994b).
Sander dust is often burned in various boiler types at plywood, particle board, and
furniture plants. Sander dust contains fine wood particles with low moisture content (less than
20 percent by weight). It is fired in a flaming horizontal torch, usually with natural gas as an
ignition aid or supplementary fuel (U.S. EPA, 1994b).
A recent development in wood-firing is the FBC boiler. Refer to Utility Sector for
a description of this boiler-type. Because of the large thermal mass represented by the hot inert
bed particles, FBCs can handle fuels with high moisture content (up to 70 percent, total basis).
Fluidized beds can also handle dirty fuels (up to 30 percent inert material). Wood material is
pyrolyzed faster in a fluidized bed than on a grate due to its immediate contact with hot bed
material. As a result, combustion is rapid and results in nearly complete combustion of organic
matter, thereby minimizing emission of unbumed organic compounds (U.S. EPA, 1994b).
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The composition of wood waste depends largely on the industry from which it
originates and may have an impact on POM emissions. Pulping operations, for example, produce
great quantities of bark that may contain more than 70 percent by weight moisture, along with
sand and other noncombustibles. Because the high moisture content and the presence of
noncombustibles inhibits complete combustion, bark boilers in pulp mills may emit considerable
amounts of organic compounds to the atmosphere unless they are well controlled. On the other
hand, some operations, such as furniture manufacturing, produce a clean, dry wood waste, 5 to
50 percent by weight moisture, with relatively low organic emissions when properly burned.
Still other operations, such as sawmills, burn a varying mixture of bark and wood waste that
results in particulate emissions somewhere between those of pulp mills and furniture
manufacturing. Additionally, when fossil fuels are co-fired with wood waste, the combustion
efficiency is typically improved; therefore, organic emissions may decrease (U.S. EPA, 1997).
The ratio of overfire to underfire air also plays an important role in organic
emissions. Based on test results, it has been speculated that if the balance of combustion air
heavily favors underfire air, there is insufficient combustion air in the upper furnace to complete
the combustion of the products of incomplete combustion (PICs) (including POM). Conversely,
with excessive overfire air, the flame quenching effect of too much combustion air in the upper
furnace appears to suppress the combustion of the PICs at that stage of the combustion process
(Hubbard, 1991).
Waste Oil Combustion-Waste oil is another type of fuel that is burned primarily in small
industrial/commercial boilers and space heaters. Space heaters are small combustion units
(generally less than 250,000 Btu/hr [0.1 MW] heat input) that are common in automobile service
stations and automotive repair shops where supplies of waste crankcase oil are available
(U.S. EPA, 1995c).
Waste oil includes used crankcase oils from automobiles and trucks, used
industrial lubricating oils such as metal working oils, and other used industrial oils such as heat
transfer fluids. When discarded, these oils become waste oils due to a breakdown of physical
properties and to contamination by other materials. The different types of waste oils may be
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burned as mixtures or as single fuels where supplies allow. Boilers designed to burn No. 6
(residual) fuel oils or one of the distillate fuel oils can be used to burn waste oil, with or without
modifications for optimizing combustion. As an alternative to boiler modification, the properties
of waste oil can be modified by blending it with fuel oil, to the extent required to achieve a
clean-burning fuel mixture.
Emission Control Techniques-POM emissions from industrial/commercial boilers may be
dependent on various factors, including: (1) the type of fuel burned, (2) the type of boiler used,
(3) operation conditions of the boiler, and (4) pollution control device(s) used. Conditions that
favor more complete combustion of the fuel generally result in lower organic emissions.
Additionally, the organic emission potential of wood combustion is generally thought to be
greater than that of fossil fuel combustion because wood waste has a lower heating value and
higher moisture content, which may decrease combustion efficiency.
The type of boiler, as well as its operation, affects combustion efficiency and
emissions. Wood-fired boilers require a sufficiently large refractory surface to ensure proper
drying of high-moisture-content wood waste prior to combustion. Adequately dried fuel is
necessary to avoid a decrease in combustion temperatures, which may increase organic emissions
because of incomplete combustion (U.S. EPA, 1997). Flyash reinjection, which is commonly
used in large wood-fired boilers to improve fuel efficiency, may increase PM and particulate
POM emissions. The process involves the reinjection of multicyclone collected flyash to the
boiler, thus increasing PM loading to air emission control device(s). In modern flyash reinjection
boiler installations, the collected flyash is segregated into large and small sizes via sand
classifiers before reinjection of the large carbonaceous particles and disposal of the smaller,
mostly inorganic fraction (U.S. EPA, 1995a).
Emission controls for industrial boilers and their effect on POM emissions are
very similar to those previously described for utility boilers. Particulate matter control in the
industrial sector is being achieved by the use of baghouses, ESPs, wet scrubbers, and
multicyclones. For SO2 control, FGD systems are much less frequent in the industrial sector as
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opposed to the utility sector; however, they are used. Generally, in the industrial sector, SO2
regulations are met through the burning of lower sulfur content fuels (Mead et al., 1986;
Kelly, 1983).
Paniculate matter emissions from oil-fired industrial boilers are generally not
controlled under existing regulations because emission rates are low relative to coal-fired
sources. Some areas may limit SO2 emissions from oil firing by specifying the use of lower
sulfur content oils. Natural gas industrial boilers are generally uncontrolled because of very low
emissions PM and SO2 relative to coal and oil sources (Mead et al., 1986; Kelly, 1983).
Wood-fired industrial boilers are typically controlled by multicyclones followed
by venturi or impingement-type wet scrubbers for PM control. A limited number of wood-fired
boiler installations use ESPs for PM control. The effect of both of these control systems on POM
emissions reduction is estimated to be similar to that obtained at coal-fired units using the same
technology (i.e., potentially good paniculate and vaporous POM control with scrubbers and
effective paniculate POM, but no vaporous POM control with ESPs). Bagasse-fired boilers are
also controlled with predominantly wet scrubbers and, to a lesser extent, multicyclones
(Mead et al., 1986; Kelly, 1983).
Unless the facilities are unusually large, emissions control at commercial/
institutional sources is marginal or even nonexistent. In boilers with controls, the control system
generally only consists of multicyclones. Multicyclones would effect some control on larger
paniculate POM, but would have no control impact on fine paniculate POM and gaseous POM
compounds (Mead et al., 1986; Kelly, 1983).
Emission Factors
Extensive POM emissions data for utility, industrial and commercial stationary
external combustion sources are available in the technical literature. Because of their propensity
to form and release POM emissions and the applicability of State and Federal air pollution
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regulations which often require testing for emissions of toxic air pollutants, a significant current
database of emissions from these fuel combustion sources exists.
Emission factors for utility, industrial and commercial stationary external
combustion source categories are presented in Tables 4.1.2-1 to 4.1.2-13 and discussed under the
following sub-headings:
• Wood waste combustion;
• Wood waste-fired industrial boilers;
• Natural gas-fired utility boilers;
• Natural gas-fired industrial and commercial/institutional boilers;
• Anthracite coal combustion;
• Coal-fired utility boilers;
• Coal-fired industrial and commercial/institutional boilers;
• Oil-fired boilers;
• Oil-fired industrial process heaters;
• Waste oil-fired space heaters; and
• Bagasse combustion.
Wood Waste Combustion-General PAH emission factors for uncontrolled wood waste
combustion in utility, industrial and commercial boilers are presented in Table 4.1.2-1. The
emission factor units are Ib (kg) per ton (Mg) of wood waste combusted on an as fired basis of
50 percent moisture and 4,500 Btu/lb (2,500 kcal/kg). U.S. EPA (1995a) reports these emission
factors as widely applicable to all utility, industrial and commercial wood waste combustion SCC
categories. However, due to the wide range of boiler sizes, boiler and control device
configurations and fuel characteristics represented by these composite emission factors, it is
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recommended that the reader utilize the process specific emission factors presented below if
information exists to more accurately characterize the emission source.
Wood Waste-Fired Industrial Boilers—Average emission factors for industrial wood waste-fired
boilers are presented in Table 4.1.2-2. The emission factors are based on two comprehensive
toxic air emission testing programs involving facilities in California and North Carolina. The
summarized results of both studies were used to obtain the average PAH emission factors and
emission factor ranges in Table 4.1.2-2. The emission factors are representative of a range of
boiler designs and capacities, control configurations and wood waste composition.
In one study, conducted by the Timber Association of California (TAC),
11 boilers ranging from 6 to 167 Ib (13 to 368 kg) of steam per hour were tested. Five boiler
types were included in the testing program: fuel cell, dutch oven, stoker, air injection and
fluidized bed. The range of control devices represented in the sample set included cyclones,
multicyclones, ESPs and wet scrubbers. Sampling was conducted using CARB Method 429,
which captures both vapor phase and paniculate PAHs (Sassenrath, 1991).
In another study, test data from seven industrial wood waste-fired boilers in North
Carolina were summarized. Tested units included horizontal four return tube (HRT) boilers, one
underfeed stoker, one watertube boiler and one fluidized bed boiler. The rated capacity range of
the tested units was 5 to 70 MMBtu/hr (1.5 to 20.5 MW). Four of the tested units used
multicyclones for air emission control and three were uncontrolled. Wood waste fuel types fired
during testing included green and dry hardwood and softwood wood waste and bark. Sampling
was conducted using EPA Modified Method 5, which captures both vapor phase and particulate
POM, followed by GC analysis (NCASI, 1983; Sassenrath, 1991).
Naphthalene was the predominant PAH detected in both studies followed by
phenanthrene, fluorene and pyrene. Sassenrath (1991) concluded from the TAC study that PAH
emissions from properly operated modern wood waste-fired boilers were low relative to earlier
estimates and very low relative to less efficient residential wood combustion. Benzo(a)pyrene
was only detected in one sample of the test series.
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Table 4.1.2-3 presents PAH emission factors for bark-fired industrial boilers. A
single spreader stoker operating at 131,500 to 138,900 Ib (59,648 to 63,005 kg) of steam per hour
was tested. The boiler was firing redwood and fir bark during testing. Sampling for PAHs was
conducted using CARS Method 429. The emission factors represent both vapor phase and
paniculate PAHs.
Table 4.1.2-4 lists PAH emission factors for wood waste-fired industrial boilers of
greater than 50,000 Ib (22,680 kg) of steam per hour capacity. Emission factors for several
specific boiler designs, capacities, fuel types and control device configurations are presented. All
emission factors represent both vapor phase and particulate PAHs. The table contains PAH
emission factors for the following boiler and control device scenarios: a dutch oven wood waste
boiler controlled by multicyclone, a fuel cell boiler controlled by multicyclone, an air injection
burner controlled by multicyclone, three stokers, two controlled by multicyclone and wet
scrubber in series and one controlled by multicyclone and ESP in series and one fluidized bed
wood waste boiler controlled by multicyclone and ESP in series. Where available, the operating
load during testing in Ib (kg) of steam per hour and the specific fuel source are footnoted in the
table.
PAH emission factors for wood waste-fired industrial boilers less than 50,000 Ib
(22,680 kg) of steam per hour capacity are presented in Table 4.1.2-5. Two units were tested,
one cyclone-controlled fuel cell firing fir sawdust fuel and one boiler of unknown design
controlled with a wet scrubber firing cedar chips. The steaming rate range represented in the test
data was 6,400 to 34,000 Ib (2,903 to 15,422 kg) of steam per hour. Sampling and analytical
methods were used to quantify both vapor phase and particulate PAHs.
Natural Gas-Fired Utility Boilers—PAH emission factors for natural gas-fired utility boilers are
listed in Table 4.1.2-6. The emission factors are based on test data from two opposed-fired
natural gas-fired utility boilers, one uncontrolled and one with flue gas recirculation. The
uncontrolled utility boiler was a 2,561 MMBtu/hr (750 MW) unit. Sampling was conducted
using CARB Method 429 followed by GC/MS analysis. The 16 commonly tested PAHs were
analyzed in the study, but only three, anthracene, naphthalene, and phenanthrene, were
4-57
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determined to be present above the detection limits in any sample (Booth, 1992). The second
unit tested was a 785 MMBtu/hr (230 MW) utility boiler with flue gas recirculation. Stack gases
from this unit were sampled using CARB Method 430 at three operating loads, 109 MW,
159 MW and 222 MW. Both sets of emission factors represent both vapor phase and particulate
PAHs. Naphthalene was the predominant PAH detected in the emissions from both units.
Natural Gas-Fired Industrial and Commercial/Institutional Boilers—PAH emission factors for
industrial and commercial/institutional boilers are presented in Table 4.1.2-7. The industrial
natural gas-fired boiler emission factors are composite factors based on 10 uncontrolled units.
The following boiler designs were included in the emissions database: two fire-tube, one scotch,
and seven water-tube. The sample included a rated capacity range of 7.2 to 178 MMBtu/hr
(2.1 to 52 MW). The commercial/institutional boiler emission factors are based on data from
five tested uncontrolled packaged watertube boilers ranging in capacity from 17.4 to
126 MMBtu/hr (5.1 to 37 MW). Sampling for both data sets was conducted using the Source
Assessment Sampling System (SASS). The system was designed to trap particulate and gases
from the flue gas stream, separating particulate and adsorbing organics on XAD-2 resin. The
particulate and vapor phase PAHs were then analyzed using GC/MS. As in the utility boiler data,
naphthalene was the predominant PAH detected in the emissions from natural gas-fired industrial
and commercial/institutional boilers (Johnson et al., 1990; Surprenant et al., 1981).
Anthracite Coal Combustion—PAH emission factors for anthracite coal combustion are listed in
Table 4.1.2-8. According to U.S. EPA (1995a) the emission factors are applicable to
uncontrolled utility, industrial and commercial/institutional stoker anthracite combustion.
However, the factors are based on test data from three commercial/institutional stoker boilers,
and thus, may have limited applicability in predicting PAH emissions from large modern utility
and industrial boilers. The tested units had a rated capacity range of 8.7 to 87 MMBtu/hr (2.5 to
25 MW). Only two of the 16 commonly tested PAHs, naphthalene and phenanthrene, were
detected in the analysis of samples from the three tested boilers. The reported emission factors
represent both vapor phase and particulate PAHs.
4-58
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Coal-Fired Utility Boilers—PAH emission factors for bituminous and lignite coal-fired utility
boilers are presented in Table 4.1.2-9. The table includes composite emission factors for
bituminous pulverized wet-bottom boilers, bituminous pulverized dry-bottom boilers, and
lignite-fired boilers. The pulverized wet-bottom boiler average emission factors are based on six
tested utility boilers with a rated capacity range of 376 to 2,834 MMBtu/hr (110 to 830 MW).
The pulverized dry-bottom boiler average emission factors are based on test data from six boilers
with a rated capacity range of 263 to 1,707 MMBtu/hr (77 to 500 MW). The lignite-fired boiler
composite emission factors are based on nine tested utility boilers, five pulverized dry-bottom
boilers, two cyclones and two spreader stokers with a rated capacity range of 68 to
1,434 MMBtu/hr (20 to 420 MW). All three sets of composite emission factors represent units
with a range of common control configurations including multicyclones, ESPs and scrubbers.
The emission factors include both vapor phase and paniculate PAHs (Johnson et al., 1990;
Shihetal., 1980).
In addition to these composite emission factors, three source/control specific
emission factor sets are presented. These include a bituminous coal-fired cyclone boiler
equipped with an ESP, a bituminous coal-fired cyclone boiler equipped with a baghouse and a
combined SO2 and NOX control system (SNOX) and a pulverized lignite-fired tangential
dry-bottom boiler equipped with an ESP and wet FGD (Sverdrup et al., 1994). Information on
the specific boilers used in emission factor development, including operating rates and control
devices is presented in footnotes to the emission factor sets in Table 4.1.2-10. All emission
factors represent both vapor phase and paniculate PAH emissions.
Coal-Fired Industrial and Commercial/Institutional Boilers—PAH emission factors for coal-fired
industrial and commercial/institutional boilers are listed in Table 4.1.2-10. Composite emission
factors for two industrial boiler design categories, pulverized bituminous coal-fired wet and
dry-bottom boilers and bituminous stokers, are presented. The pulverized bituminous coal-fired
industrial boiler emission factors are based on test data from seven units, both wet and
dry-bottom, with a rated capacity range of 116 to 1,261 MMBtu/hr (34 to 366 MW). Five of the
seven units were multicyclone controlled, three were ESP controlled and one unit had a FGD
system. Test data from 17 bituminous coal-fired stokers was used in deriving composite PAH
4-59
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emission factors for this design category. The sample set included 11 spreader stokers, five
overfeed stokers and one underfeed stoker. Control configurations included uncontrolled,
multicyclone controlled and ESP controlled. Both PAH emission factor sets represent both vapor
phase and paniculate emissions (Johnson et al., 1990; Shih et al., 1980).
The PAH emission factor set for coal-fired commercial/institutional boilers is
based on testing from a single uncontrolled bituminous coal-fired underfeed stoker. The rated
capacity of the boiler was 2.2 MMBtu/hr (0.63 MW). During testing, the boiler was operated at
low heat input levels, possible contributing to the relatively high POM emissions. The reported
emission factors include both vapor phase and particulate PAHs (Johnson et al., 1990;
Shih et al., 1980).
Oil-Fired Boilers—PAH emission factors for oil-fired utility, industrial and
commercial/institutional boilers are presented in Table 4.1.2-11. Emission factor ranges from
multiple uncontrolled residual oil-fired utility boilers were presented by Booth (1992). The test
data used to develop the PAH emission factor ranges were compiled from CARB AB-2588
facility emissions test reports. Boiler designs included in the database included front- and
opposed-fired boilers with a rated capacity range of 188 to 2,523 MMBtu/hr (55 to 739 MW).
Sampling for all test data was conducted using CARB Method 429 followed by GC/MS analysis.
Both vapor phase and particulate PAHs are included in the emission factors. Booth (1992) noted
that naphthalene, the predominant PAH identified in the study, was a decomposition product of
the XAD-2 resin used in the CARB Method 429 sampling protocol, possibly raising questions
about the validity of the naphthalene emissions estimates. Insufficient data were available in the
study to calculate average emission factors; however, median emission factors may be used for
general application if information is not available to further characterize the emissions source.
Emission factors for three-specific utility boiler and control configurations are
listed in Table 4.1.2-12. The three boilers tested were a No. 6 oil wall-fired uncontrolled utility
boiler, a No. 6 oil wall-fired utility boiler with flue gas recirculation and a No. 5 oil-fired utility
boiler with flue gas recirculation. The boiler rated capacities were 598 MMBtu/hr (1,75 MW),
1,639 MMBtu/hr (480 MW) and 785 MMBtu/hr (230 MW), respectively. Sampling for all three
4-60
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data sets was conducted using CARB Method 429 followed by GC/MS analysis. The emission
factors represent both vapor phase and paniculate PAHs.
PAH emission factors for No. 6 oil-fired industrial boilers are presented in
Table 4.1.2-12. The data used in factor development came from testing of a single uncontrolled
unit. Testing was conducted using CARB Method 429 followed by GC/MS analysis. The
emission factors represent both vapor phase and particulate PAHs.
PAH emission factors for No. 2 oil-fired industrial and commercial/institutional
boilers are also listed in Table 4.1.2-12. The average emission factors are based on eight tested
units. Included in the data set were five water-tube industrial boilers with a rated capacity range
of 23 to 529 MMBtu/hr (6.7 to 155 MW) and three commercial/institutional boilers, one cast iron
and two water-tube, with a rated capacity range of 5 to 35 MMBtu/hr (1.5 to 10.3 MW). Test
methods were used to quantify both particulate and vapor phase POM. PAH emissions were
reported as being below detection limits for several of the tested units (Johnson et al., 1990;
Surprenant et al., 1980).
Oil-Fired Industrial Process Heaters-PAH emission factors for oil-fired industrial process
heaters are presented in Table 4.1.2-12. The emission factors were developed using test data
from a single 20,800 Btu/hr (6,092 MW) direct fire pipeline fuel oil heater firing residual oil.
PAH emissions sampling and analytical methods used were CARB Method 429 and GC/MS,
respectively. Emission factors represent both vapor phase and particulate PAHs.
Waste Oil-Fired Space Heaters--PAH emission factors for waste oil combustion are shown in
Table 4.1.2-13. Emission factors have been determined for emissions from two basic types of
uncontrolled space heaters: a vaporizing pot type burner and an air atomizing burner. The use of
both blended and unblended fuels is included in the factors that were obtained from U.S. EPA
(1995c). The factors obtained from Cooke et al. (1984), are based on the combustion of filtered,
but otherwise untreated waste crankcase oil from automobiles. Both sets of factors are based on
samples of stack effluent from waste oil heaters rated at less than 0.1 MW.
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The vaporized pot design showed higher emissions of PAH than did the atomizing
burner space heater. In a vaporized pot burner only the heater vaporized fuel is combusted. In
the air atomizing burner the fuel is atomized and then burned, resulting is much less residue of
unbumed material than the vaporized pot burner. Cooke et al. (1984), reported that the
combustion of waste oil in the vaporized pot burner that they tested resulted in higher PAH
emissions than those reported for residential space heaters burning distillate oil.
Bagasse Combustion—Very limited data on emissions from bagasse combustion in boilers were
available in the literature. One test report quantified total paniculate and vapor phase POM
emissions from two industrial bagasse-fired boilers in Hawaii (Baladi, 1976). The study reported
total POM emissions from multicyclone controlled bagasse-fired boilers of 4.00E-5 to 1.80E-4
Ib/MMBtu (1.72E-5 to 7.75E-5 g/MJ). The limited speciation data reported in the study
indicated that none of the 16 commonly investigated PAHs were present above detection limits
in the samples. The predominant POM compounds measured were 3-methylcholanthrene and
7,12-dimethyl-benz(a)anthracene. Due to the age of the data and the limited speciation of the
total POM measured, individual PAH emission factors were not developed for this source
category.
Source Locations
Most of the U.S. utility coal-firing capability is east of the Mississippi River, with
the significant remainder being in the Rocky Mountain region. Natural gas is used primarily in
the South Central States and California. Oil is predominantly used in Florida and the Northeast.
Fuel economics and environmental regulations affect regional use patterns. For example, coal is
not used in California because of stringent air quality limitations. Information on precise utility
plant locations can be obtained by contacting utility trade associations such as the Electric Power
Research Institute in Palo Alto, California (415-855-2000); the Edison Electric Institute in
Washington, DC (202-828-7400); or the U.S. Department of Energy (DOE) in Washington, DC.
Industrial and commercial coal combustion sources are located throughout the
United States, but tend to follow industry and population trends. Most of the coal-fired industrial
4-62
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boiler sources are located in the Midwest, Appalachian, and Southeast regions. Industrial
wood-fired boilers tend to be located almost exclusively at pulp and paper, lumber products, and
furniture industry facilities. These industries are concentrated in the Southeast, Gulf Coast,
Appalachian, and Pacific Northwest regions.
Trade associations such as the American Boiler Manufacturers Association in
Arlington, Virginia (703-522-7350) and the Council of Industrial Boiler Owners in Fairfax
Station, Virginia (703-250-9042) can provide information on industrial boiler locations and
trends (U.S. EPA, 1997).
4-63
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TABLE 4.1.2-1. PAH EMISSION FACTORS FOR WOOD WASTE COMBUSTION
Control
SCC Number Emission Source Device Pollutant
1-01-009-01, -02, Wood Waste Fired None Benz(a)anthracene
-03, -04, -05, Boiler
-06, -07
Benzo(a)pyrene
Benzo(b + k)fluoranthene
Chrysene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Average Emission
Factor in Ib/ton
(kg/Mg)1
1.8E-06
(9.0E-07)
1.9E-07
(9.5E-08)
2.9E-05
(1.5E-05)
4.3E-05
(2.1E-05)
3.4E-07
(1.7E-07)
3.4E-06
(1.7E-06)
4.4E-05
(2.2E-05)
3.8E-05
(1.9E-05)
1.2E-06
(6.0E-07)
9.0E-05
(4.5E-05)
9.6E-06
(4.8E-06)
Emission Factor Range in Ib/ton
(kg/Mg)1
8.6E-8 - 6.4E-6
(4.3E-8 - 3.2E-6)
8.6E-8 - 3.0E-7
(4.3E-8- 1.5E-7)
3.4E-7- 1.9E-4
(1.7E-7-9.5E-5)
8.6E-8 - 3.0E-4
(4.3E-8- 1.5E-4)
8.6E-8 - 6.0E-7
(4.3E-8 - 3.0E-7)
8.6E-8 - 4.3E-6
(4.3E-8-2.1E-6)
6.0E-7 - 6.8E-5
(3.0E-7 - 3.4E-5)
8.6E-8 - 3.5E-4
(4.3E-8-1.7E-4)
8.6E-8 - 3.5E-6
(4.3E-8-1.7E-6)
8.6E-8 - 8.6E-4
(4.3E-8 - 4.3E-4)
1.7E-7-2.8E-5
(8.5E-8-1.4E-5)
Emission
Factor
Rating
C
D
C
C
D
C
C
C
C
C
C
(continued)
-------
TABLE 4.1.2-1. (Continued)
Average Emission
Control Factor in Ib/ton
SCC Number Emission Source Device Pollutant (kg/Mg)a
1-01-009-01, -02, Wood Waste Fired None Naphthalene 2.3E-03
-03, -04, -05, Boiler (continued) (1.1E-03)
-06, -07
(continued)
Phenanthrene 5.7E-05
(2.8E-05)
Pyrene 1.7E-05
(8.5E-06)
Methyl anthracene 1.4E-04
*. (7.00E-05)
in
Emission Factor Range in Ib/ton
(kg/Mg)a
5.0E-5 -
(2.5E-5 -
2.0E-6 -
(l.OE-6-
4.3E-7 -
(2.1E-7-
-
5.8E-3
2.9E-3)
1.8E-4
9.0E-5)
5.9E-5
2.9E-5)
-
Emission
Factor
Rating
C
C
C
D
'Emission factors are in Ib (kg) per ton (Mg) of wood waste burned. Emission factors are based on wet, as fired wood waste with average
properties of 50 percent moisture and 4,500 Btu/lb higher heating value.
Source: U.S. EPA, 1995a.
-------
TABLE 4.1.2-2. PAH EMISSION FACTORS FOR INDUSTRIAL WOOD WASTE BOILERS
sec
Number Emission Source Control Device Pollutant
1-02-009-01, Wood Waste Fired (d) Benz(a)anthracene
-02, -03, - Boiler0
04, -05, -06
Benzo(a)pyrene
Benzo(b + k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Average Emission
Factor in Ib/ton
(kg/Mg)a
(2.70E-05
«1.35E-05)
7.01E-06
(3.50E-06)
0.10E-05
((5.50E-06)
<9.00E-06
(4.50E-06)
2.00E-06
(l.OOE-06)
3.00E-06
(1.50E-06)
(2.00E-06
(1.00E-06)C
7.20E-05
(3.60E-05)6
6.60E-05
(3.30E-05)
(7.00E-06
(3.50E-06)
2.50E-05
(1.25E-05)
Emission Factor Range in Ib/ton
(kg/Mg)b
<2.0E-6 - 5.2E-5
(U.OE-6-2.6E-5)
2.0E-8- 1.4E-5
(1.0E-8-7.0E-6)
(2.0E-6 - 2.0E-5
«1.0E-6- l.OE-5)
<2.0E-6-1.6E-5
(<1.0E-6-8.0E-6)
0.0 - 4.0E-6
(0.0 - 2.0E-6)
<2.0E-6 - 4.0E-6
((1.0E-6-2.0E-6)
—
—
4.0E-6-1.28E-4
(2.0E-6 - 6.4E-5)
<2.0E-6-1.2E-5
(1.0E-6-6.0E-6)
1.4E-5-3.6E-5
(7.0E-6- 1.8E-5)
Emission
Factor
Rating
C
C
C
C
C
C
C
C
C
C
C
(continued)
-------
TABLE 4.1.2-2. (Continued)
sec
Number Emission Source Control Device Pollutant
1-02-009-01, Wood Waste Fired Fluorene
-02, -03, - Boiler0 (continued)
04, -05, -06
(continued)
Naphthalene
(d) Phenanthrene
Pyrene
Average Emission
Factor in Ib/ton
(kg/Mg)a
5.70E-05
(2.85E-05)
0.00288
(0.00144)
1.51E-04
(7.55E-05)
4.20E-05
(2.10E-05)
Emission Factor Range in Ib/ton
(kg/Mg)b
1.2E-5-
(6.0E-6 -
0.00263 -
(0.00131 -
8.6E-5 -
(4.3E-5 -
3.4E-5 -
(1.7E-5-
1.02E-4
5.1E-5)
0.00313
0.00156)
2.16E-4
1.08E-4)
5.0E-5
2.5E-5)
Emission
Factor
Rating
C
C
C
C
'Emission factors are in Ib (kg) per ton (Mg) of wood waste burned (moisture conditions as fired).
Emission factor range represents range between two sets of summarized emission factors. Emission factor set No. 1 is the mean of 11 tested
boilers by the Timber Association of California. Emission factor set No. 2 is the mean of 7 boilers tested in North Carolina by the National
Council of the Paper Industry for Air and Stream Improvement (NCASI).
Includes test data from several boiler designs including stoker, dutch oven, fuel cell, and fluidized bed.
dlncludes test data from several boiler air emission control systems including multiple cyclones, ESPs, and scrubbers.
'Pollutants not measured in NCASI Study.
Source: Sassenrath, 1991.
-------
TABLE 4.1.2-3. PAH EMISSION FACTORS FOR BARK-FIRED INDUSTRIAL BOILERS
£
oo
SCC Number Emission Sourceb Control Device Pollutant
1-02-009-01 Stoker Multiple Cyclone/Electrostatic Acenaphthene
Precipitator
Acenaphthylene
Anthracene
Fluoranthene
Fluorene
Phenanthrene
Pyrene
Average Emission
Factor in Ib/MMBtu
(g/MJ)1
0.5E-08
(6.4E-09)
7.4E-06
(3.2E-06)
(1.9E-07
(8.2E-08)
2.1E-06
(9.0E-07)
2.0E-07
(8.6E-08)
6.8E-06
(2.9E-06)
1.2E-06
(5.2E-07)
Emission
Factor
Rating
D
D
D
D
D
D
D
"Emission factors are in Ib (g) of pollutant per MMBtu (MJ) of heat input.
bEmission source: Spreader stoker operated at 131,500 to 138,900 Ib (59,648 to 63,005 kg) steam/hr firing redwood and fir bark.
Source: Source Emission Testing of the Wood-fired Boiler "C" Exhaust at Pacific Timber, Scotia, California. Performed for the Timber
Association of California. Galston Technical Services, February 1991.
-------
TABLE 4.1.2-4. PAH EMISSION FACTORS FOR WOOD WASTE-FIRED INDUSTRIAL BOILERS >50,000 LB STEAM/HR
ON
vo
Average Emission Factor in Emission Factor Emission
SCC Emission Control
Number Source Device Pollutant
1-02-009-03 Dutch Ovenb Multiple Benzo(k)fluoranthene
Cyclone0
Acenaphihene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
1-02-009-03 Fuel Cell Multiple Benzo(a)pyrene
Cyclone0
Chrysene
Indeno( 1 ,2,3-cd)pyrene
Ib/MMBtu
(g/MJ)a
<1.50E-07
«6.45E-08)
<1.20E-07
«5.16E-08)
<3.80E-06
«1.63E-06)
<1.40E-07
(<6.02E-08)
6.00E-08
(2.58E-08)
9.60E-07
(4.13E-07)
<7.00E-08
«3.01E-08)
d
2.10E-06
(9.03E-07)
1.30E-06
(5.59E-07)
<7.50E-09
(<3.22E-09)
5.40E-08
(2.32E-08)
<1.20E-08
«5.16E-09)
Range in Ib/MMBtu Factor
(g/MJ)a Rating
D
D
D
D
D
D
D
...
D
D
D
D
D
Reference
FIREj
FIRE*
FIREj
FIRE*
FIRE*
FIREJ
FIRE*
FIREj
FIREJ
FIREj
FIREk
FIREk
FIREk
(continued)
-------
TABLE 4.1.2-4. (Continued)
SCC Emission Control
Number Source Device
1-02-009-03 Fuel Cell Multiple
(continued) (continued) Cyclone0
(continued)
1-02-009-03 Air Injection Multiple
Burner* Cyclone0
Pollutant
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
Benz(a)anthracene
Chrysene
Indeno( 1 ,2,3-cd)pyrene
Average Emission Factor in
Ib/MMBtu
(g/MJ)a
<6.50E-09
(<2.79E-09)
2.80E-07
(1.20E-07)
<1.30E-08
(<5.59E-09)
<1.10E-08
(<4.73E-09)
4.00E-07
(1.72E-07)
<3.10E-08
(<1.33E-08)
d
4.30E-07
(1.85E-07)
2.40E-07
(1.03E-07)
4.20E-08
(1.81E-08)
1.20E-07
(5.16E-08)
6.80E-08
(2.92E-08)
Emission Factor Emission
Range in Ib/MMBtu Factor
(g/MJ)a Rating
D
D
D
D
D
D
D
D
D
D
D
D
Reference
FIREk
FIREk
FIREk
FIREk
FIREk
FIREk
FlREk
FIREk
FIREk
FIRE1
FIRE1
FIRE1
(continued)
-------
TABLE 4.1.2-4. (Continued)
SCC Emission Control
Number Source Device Pollutant
1-02-009-03 Air Injection Multiple Acenaphthene
(continued) Burner6 Cyclone0
(continued) (continued)
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
1-02-009-03 Stokerf Multiple Acenaphthylene
Cyclone/
Electrostatic
Precipitatorc
Fluoranthene
Naphthalene
Average Emission Factor in
Ib/MMBtu
(g/MJ)a
4.90E-07
(2.11E-07)
5.00E-06
(2.15E-06)
2.70E-07
(1.16E-07)
4.00E-07
(1.72E-07)
4.90E-06
(2.11E-06)
1.30E-07
(5.59E-08)
d
6.00E-06
(2.58E-06)
6.40E-06
(2.75E-06)
4.80E-07
(2.06E-07)
<1.98E-08
(<8.49E-09)
2.00E-04
(8.60E-05)
Emission Factor Emission
Range in Ib/MMBtu Factor
(g/MJ)a Rating
D
D
D
D
D
D
—
D
D
D
<6.50E-9 - 3.30E-8 C
(<2.79E-9- 1.42E-8)
1.20E-4-2.80E-4 C
(5.16E-5-1.20E-4)
Reference
FIRE1
FIRE1
FIRE1
FIRE1
FIRE1
FIRE1
FIRE1
FIRE1
FIRE1
FIRE™
FIRE"1'"
FIRE"1'"
(continued)
-------
TABLE 4.1.2-4. (Continued)
f-
-j
to
SCC Emission Control
Number Source Device Pollutant
1-02-009-03 Stoker* Multiple Phenanthrene
(continued) (continued) Cyclone/
Electrostatic
Precipitator0
(continued)
Pyrene
1-02-009-03 Fluidized Multiple Benz(a)anthracene
Bed* Cyclone/
Electrostatic
Precipitator0
Chrysene
Acenaphthylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Average Emission Factor in
Ib/MMBtu
(g/MJ)a
1.70E-07
(7.31E-08)
4.30E-08
(1.85E-08)
<7.60E-09
«3.27E-09)
2.00E-08
(8.60E-09)
7.50E-08
(3.22E-08)
2.20E-07
(9.46E-08)
<2.50E-08
«1.07E-08)
<6.60E-04
«2.84E-04)
4.90E-07
(2.11E-07)
Emission Factor Emission
Range in Ib/MMBtu Factor
(g/MJ)a Rating
D
D
D
D
D
D
D
D
D
Reference
FIREm
FIREm
FIRE0
FIRE0
FIRE0
FIRE0
FIRE"
FIRE0
FIRE0
(continued)
-------
TABLE 4.1.2-4. (Continued)
-4
U>
Average Emission Factor in Emission Factor Emission
SCC Emission Control
Number Source Device
1-02-009-03 Fluidized Multiple
(continued) Bedg Cyclone/
(continued) Electrostatic
Precipitatorc
(continued)
1-02-009-03 Stoker11 Multiple
Cyclone/
Wet
Scrubber0
Pollutant
Pyrene
Benz(a)anthracene
Benzo(k)fluoranthene
Chrysene
Acenaphthene
Acenaphlhylene
Anthracene
Fluoranthene
Fluorene
Naphthalene
Ib/MMBtu
(g/MJ)a
5.10E-08
(2.19E-08)
<5.30E-09
«2.28E-09)
<2.00E-08
(<8.60E-09)
<6.70E-09
(<2.88E-09)
l.OOE-07
(4.30E-08)
3.10E-07
(1.33E-07)
2.10E-08
(9.03E-09)
8.20E-08
(3.53E-08)
5.50E-08
(2.36E-08)
<5.20E-04
K2.24E-04)
Range in Ib/MMBtu Factor
(g/MJ)a Rating
D
D
D
D
D
D
D
D
D
D
Reference
FIRE0
FIRE?
FIREP
FIREP
FIREP
FIREP
FIREP
FIREP
FIREP
FIREP
(continued)
-------
TABLE 4.1.2-4. (Continued)
SCC Emission Control
Number Source Device Pollutant
1-02-009-03 Stoker11 Multiple Phenanthrene
(continued) (continued) Cyclone/
Wet
Scrubber0
(continued)
Pyrene
1-02-009-03 Stoker* Multiple Benz(a)anthracene
Cyclone/
Wet
Scrubber0
Acenaphthene
Acenaphthylene
Anthracene
Fluoranthene
Fluorene
Naphthalene
Average Emission Factor in
Ib/MMBtu
(g/MJ)a
2.30E-07
(9.89E-08)
9.60E-08
(4.13E-08)
<1.40E-06
(<6.02E-07)
2.00E-06
(8.60E-07)
2.50E-05
(1.07E-05)
1.80E-06
(7.74E-07)
1.10E-05
(4.73E-06)
5.80E-06
(2.49E-06)
<1.90E-04
(8.17E-05)
Emission Factor Emission
Range in Ib/MMBtu Factor
(g/MJ)a Rating
D
D
D
D
D
D
D
D
D
Reference
FIREP
FIREp
FIRE'
FIRE'
FIRE'
FIRE'
FIRE'
FIRE'
FIRE'
(continued)
-------
TABLE 4.1.2-4. (Continued)
Average Emission Factor in Emission Factor Emission
sec
Number
1-02-009-03
(continued)
Emission
Source
Stoker*
(continued)
Control
Device Pollutant
Multiple Phenanthrene
Cyclone/
Wet
Scrubber0
(continued)
Ib/MMBtu
(g/MJ)a
3.10E-05
(1.33E-05)
Range in Ib/MMBtu Factor
(g/MJ)a Rating
D
Reference
FIREq
Pyrene
7.10E-06
(3.05E-06)
D
FIREq
f-
-4
Ul
'Emission factors are in Ib (g) of pollutant per MMBtu (MJ) of heat input.
bSource operated at 40,300 to 56,000 Ib (18,280 to 25,400 kg) steam/hr firing pine/fir hog fuel and chips.
cMultiple cyclones without flyash reinjection.
dData suspect; no emission factor developed.
'Source operated at 40,750 to 46,000 (18,484 to 20,865 kg) Ib steam/hr firing sander dust fuel.
'Sources operated at 165,820 to 174,400 Ib (75,215 to 79,107 kg) steam/hr firing pine/fir hog fuel and chips.
gSource operated at 91,500 to 93,000 Ib (41,504 to 42,184 kg) steam/hr firing pine/fir chips.
hSource operated at 90,000 Ib (40,824 kg) steam/hr firing pine/cedar hog fuel.
'Source operated at 117,000 to 126,000 Ib (53,071 to 57,153 kg) steam/hr firing redwood/fir hog fuel.
'Source Emission Testing of the CE Wood-Fired Boiler at Rosenburg Forest Products (TAG Site #3). Performed for the Timber Association of California.
Galston Technical Services, January 1991.
kSource Emission Testing of the Wood-fired Boiler at Big Valley Timber Company, Bieber, California. Performed for the Timber Association of California.
Galston Technical Services, February, 1991.
'Source Emission Testing of the Wood-fired Boiler Exhaust at Bohemia, Inc., Rocklin, California. Prepared for the Timber Association of California. Galston
Technial Services, December 1990.
""Source Emission Testing of the Wood-Fired Boiler Exhaust at Sierra Pacific, Burney, California. Performed for the Timber Association of California. Galston
Technical Services, February 1991.
"Source Emission Testing of the Wood-fired Boiler #1 Exhaust Stack at Wheelabrator Shasta Energy Company (TAG Site 9), Anderson, California. Performed
for the Timber Association of California. Galston Technical Services, January 1991.
"Source Emission Testing of the Wood-fired Boi ler at Yorke Energy, North Fork, California. Performed for the Timber Association of California. Galston
Technical Services, January 1991.
pSource Emission Testing of the Wood-fired boiler at Catalyst Hudson, Inc., Anderson California. Performed for the Timber Association of California. Oalston
Technical Services, February 1991.
^Source Emission Testing of the Wood-fired Boiler #3 Exhaust at Georgia Pacific, Fort Bragg, California. Performed for the Timber Association of California.
Galston Technical Services, February 1991.
-------
TABLE 4.1.2-5. PAH EMISSION FACTORS FOR WOOD WASTE-FIRED INDUSTRIAL BOILERS <50,000 LB STEAM/HR
-J
ON
SCC Number Emission Source Control Device Pollutant
1-02-009-06 FuelCellb Cyclone Anthracene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
1-02-009-06 Wood Waste Fired Wet Scrubber Benz(a)anthracene
Boiler0
Benzo(a)pyrene
Benzo(h)fluoranthene
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Average Emission Factor in
Ib/MMBtu (g/MJ)a
<1.30E-07
(<5.59E-08)
5.90E-07
(2.54E-07)
<1.00E-06
(<4.30E-07)
4.90E-04
(2.11E-04)
3.00E-06
(1.29E-06)
3.10E-07
(1.33E-07)
4.40E-07
(1.89E-07)
3.42E-07
(1.47E-07)
1.31E-07
(5.63E-08)
6.83E-07
(2.94E-07)
1.95E-07
(8.38E-08)
<2.57E-08
(<1.10E-08)
4.07E-07
(1.75E-07)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
D
Reference
FIREd
FIREd
FIREd
FIREd
FIREd
FIREd
FIREe
FIRE6
FIRE6
FIRE6
FIRE6
FIRE6
FIRE6
(continued)
-------
TABLE 4.1.2-5. (Continued)
SCC Number Emission Source Control Device Pollutant
1-02-009-06 Wood Waste Fired Wet Scrubber Acenaphthene
(continued) Boiler0 (continued) (continued)
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranlhene
Fluorene
Naphthalene
Phenanthrene
Pyrene
Average Emission Factor in
Ib/MMBtu (g/MJ)a
6.71E-07
(2.88E-07)
3.72E-05
(1.60E-05)
8.35E-06
(3.59E-06)
1.09E-06
(4.69E-07)
9.52E-06
(4.09E-06)
8.57E-06
(3.68E-06)
9.30E-05
(4.00E-05)
6.18E-05
(2.66E-05)
9.95E-06
(4.28E-06)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
Reference
FIREe
FIREe
FIREe
FIREe
FIRE6
FIREe
FIREe
FIRE6
FIREe
"Emission factors are in Ib (g) of pollutants per MMBtu (MJ) of heat input.
bSource operated at 6,400 to 6,802 Ib (2,903 to 3,085 kg) steam/hr firing fir sawdust fuel.
cBoiler of unknown design operated at 13,000 to 34,000 (5,897 to 15,422 kg) steam/hr firing cedar chips.
dSource Emission Testing of the Wood-fired Boiler Exhaust at Miller Redwood Co., Crescent City, California. Performed for the Timber Association of California.
Galston Technical Services, February 1991.
Determination of AB 2588 Emissions from a Wood-fired Boiler Exhaust, February 10 - 13, 1992. (Confidential Report No. ERC-63).
-------
TABLE 4.1.2-6. PAH EMISSION FACTORS FOR NATURAL GAS-FIRED UTILrrY BOILERS
oo
SCC Number Emission Source Control Device Pollutant
1-01-006-01 Opposed Fired None Fluorene
Boiler6
Naphthalene
Phenanthrene
1-01-006-01 Opposed Fired Flue Gas Chrysene
Boiler0 Recirculation
Acenaphthene
Acenaphthylene
Anthracene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
Average Emission Factor in
Ib/MMBtu
(g/MJ)a
2.0E-09
(8.6E-10)
4.5E-08
(1.9E-08)
3.7E-09
(1.6E-09)
1 45E-08
(6.3E-09)
4.57E-05
(2.0E-05)
1 85E-08
(8.0E-09)
1.25E-08
(5.4E-09)
5.02E-08
(2.2E-08)
1.45E-07
(6.2E-08)
4.78E-05
(2.1E-05)
I.80E-07
(7.7E-08)
4.75E-08
(2.0E-08)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
Reference
Booth et al.,
Booth et al..
Booth et al.,
FIRE4
FIREd
FIREd
FIREd
FIREd
FIREd
FIREd
FIREd
FIREd
1992
1992
1992
"Emission factors are in Ib (g) per MMBtu (MJ) of heat input.
b2,561 MMBtu/hr (750 MW) opposed fired utility boiler firing natural gas.
C785 MMBtu/hr (230 MW) opposed fired utility boiler operating at 372 to 758 MMBtu/hr (109 to 222 MW) firing natural gas.
dAir Toxics "Hot Spots" Source Testing of a Utility Boiler, May 1991. (Confidential Report No. ERC-17).
-------
TABLE 4.1.2-7. PAH EMISSION FACTORS FOR NATURAL GAS-FIRED INDUSTRIAL
AND COMMERCIAL/INSTITUTIONAL BOILERS
Emission Control
SCC Number Source Device Pollutant
1-02-006-01, b None Fluoranthene
-02, -03
Naphthalene
Phenanthrene
Pyrene
2-Methyl
phenanthrene
Carbazole
•**•
^ c
1-03-006-01 None Acenaphthylene
1-03-006-02
Fluoranthene
Naphthalene
Phenanthrene
Pyrene
Average Emission
Factor in Ib/MMCF
(g/kL)a
8.69E-07
(1.39E-05)
4.24E-06
(6.80E-05)
2.52E-07
(4.04E-06)
1.97E-07
(3.16E-06)
1 .37E-08
(2.19E-07)
7.74E-08
(1.24E-06)
4.99E-06
(8.0E-05)
4.37E-07
(7.0E-06)
1.75E-05
(2.8E-04)
6.24E-07
(l.OE-05)
1.87E-06
(3.0E-05)
Emission Factor Range
in Ib/MMCF
(g/kL)a
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
8.69E-6
1.39E-4)
1.47E-5
2.35E-4)
1.68E-6
2.69E-5)
1.12E-6
1.79E-5)
1.37E-7
2.19E-6)
7.74E-7
1.24E-5)
2.04E-5
3.26E-4)
2.12E-6
3.40E-5)
8.62E-5
1.38E-3)
3.37E-6
5.40E-5)
8.18E-6
1.31E-4)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
Reference
Suprenant et al., 1981
Suprenant et al., 1981
Suprenant et al., 1981
Suprenant et al., 1981
Suprenant et al., 1981
Suprenant et al., 1981
Johnson et al., 1990
Johnson et al., 1990
Suprenant et al., 1981
Johnson et al., 1990
Johnson et al., 1990
ND: Not Detected.
"Emission factors are in Ib (g) per MMCF (kL) of natural gas fired.
bAverage emission factors based on 10 units tested: 2 firetube, 1 scotch, 7 watertube. Rated capacity range: 7.2 to 178 MMBtii/hr (2.4 to 52MW).
cAverage emission factors based on 5 packaged watertube boilers tested. Rated capacity range: 17.4 to 126 MMBtu/hr (5.1 to 37 MW).
-------
f-
oo
O
TABLE 4.1.2-8. PAH EMISSION FACTORS FOR ANTHRACITE COAL COMBUSTION
SCC Number
1-01-001-02,
1-02-001-04
Emission Source Control Device Pollutant
Stoker None Naphthalene
Phenanthrene
Average Emission
Factor in Ib/ton
(kg/Mg)a
0.13
(0065)
6.8E-03
(3.4E-03)
Emission Factor
Rating
E
E
Reference
U.S. EPA. 1995b
U.S. EPA. 1995b
'Emission factors are in Ib (kg) per ton (Mg) of coal fired.
-------
TABLE 4.1.2-9. PAH EMISSION FACTORS FOR COAL-FIRED UTILITY BOILERS
f-
oo
Control
SCC Number Emission Source Device Pollutant
1-01-002-01 Pulverized Bituminous Benzo(a)pyrene
Wet-Bottomb
Benzo(b)fluoranlhene
Chrysene
Indeno( 1 ,2,3-cd)pyrene
Benzo(ghi)perylene
Fluoranthene
Naphthalene
Phenanthrene
Pyrene
1-01-002-02 Pulverized Bituminous Benz(a)anthracene
Dry-Bottom"
Benzo(a)pyrene
Benzo(b)fluoranthene
Average Emission
Factor in Ib/ton
(kg/Mg)a
1.94E-04
(9.72E-05)d
6.94E-05
(3.47E-05)
2.16E-04
(1.08E-04)
6.22E-05
(3.11E-05)
4.16E-05
(2.08E-05)
1.70E-04
(8.48E-05)
1.46E-04
(7.29E-05)
5.34E-04
(2.67E-04)
3.76E-04
(1.88E-04)
1.68E-06
(8.40E-07)
1.32E-05
(6.58E-06)
1.46E-06
(7.30E-07)
Emission Factor
Range in Ib/ton
(kg/Mg)a
ND-1.17E-03
(ND - 5.83E-04)
ND-4.16E-04
(ND - 2.08E-04)
ND- 1.29E-03
(ND - 6.47E-04)
ND - 3.74E-04
(ND-1.87E-04)
ND - 2.50E-04
(ND- 1.25E-04)
ND- 1.02E-03
(ND-5.10E-04)
ND - 4.37E-04
(ND-2.18E-04)
ND - 3.08E-03
(ND- 1.54E-03)
ND - 2.26E-03
(ND- 1.13E-03)
ND - 6.04E-06
(ND - 3.02E-06)
ND - 9.60E-05
(ND - 4.80E-05)
ND - 3.46E-06
(ND-1.73E-06)
Emission
Factor
Rating
E
D
D
D
D
D
D
D
D
D
D
D
Reference
Johnson et al., 1990
Johnson et al., 1990
Johnson et al., 1990
Johnson et al., 1990
Johnson et al., 1990
Johnson et al., 1990
Shihetal., 1980
Johnson et al., 1990
Johnson et al., 1990
Johnson et al., 1990
Johnson et al., 1990
Johnson et al., 1990
(continued)
-------
TABLE 4.1.2-9. (Continued)
oo
S3
Control
SCC Number Emission Source Device Pollutant
1-01-002-02 Pulverized Bituminous Benzo(k)fluoranthene
(continued) Dry-Bottom6
(continued)
Chrysene
Dihenz(a,h)anthracene
Indenof 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Average Emission
Factor in Ib/ton
(kg/Mg)a
8.60E-07
(4.30E-07)
2.96E-06
(1.48E-06)
4.60E-06
(2.30E-06)
2.40E-07
(1.20E-07)
5.80E-07
(2.90E-07)
1.02E-06
(5.10E-07)
1.70E-06
(8.50E-07)
9.76E-06
(4.88E-06)
9.00E06
(4.50E-06)
1.38E-06
(6.90E-07)
6.89E-04
(3.45E-04)
1.88E-05
(9.38E-06)
Emission Factor
Range in Ib/ton
(kg/Mg)»
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
ND-
(ND-
3.10E-06
1.55E-06)
1.11E-05
5.54E-06)
1.25E-05
6.27E-06)
2.40E-06
1.20E-06)
1.46E-06
7.30E-07)
3.24E-06
1.62E-06)
4.44E-06
2.22E-06)
2.76E-05
1.38E-05)
3.10E-05
1.55E-05)
5.36E-06
2.68E-06)
3.77E-03
1.89E-03)
6.28E-05
3.14E-05)
Emission
Factor
Rating Reference
D
D
D
D
D
D
D
D
D
D
D
D
Johnson et
Johnson et
Johnson et
Johnson et
Johnson et
Johnson et
Johnson et
al.,
al..
al..
al.,
al.,
al.,
al.,
Johnson et al.,
Johnson et
al.,
Johnson et al.,
Shih et al.,
Johnson et
1990
1990
1990
1990
1990
1990
1990
1990
1990
1990
1980
al..
1990
(continued)
-------
TABLE 4.1.2-9. (Continued)
Control
SCC Number Emission Source Device Pollutant
1-01-002-02 Pulverized Bituminous f Pyrene
(continued) Dry-Bottome
(continued)
1-Nitropyrene
Benzo(a)fluorene
Benzo(e)pyrene
Methylanthracenes
Methylphenanthrcnes
£
u> Triphenylene
1-01-002-03 Bituminous Cyclone8 ESP Benz(a)anthracene
Benzo(a)pyrene
Benzo(b+k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Average Emission
Factor in Ib/ton
(kg/Mg)a
9.46E-06
(4.73E-06)
2.48E-06
(1.24E-06)
4.86E-06
(2.43E-06)
2.60E-07
(1.30E-07)
1.01E-05
(5.04E-06)
2.92E-06
(1.46E-06)
l.OOE-07
(5.00E-08)
3.72E-09
(1.60E-09)h
1.16E-09
(5.00E-10)h
6.98E-09
(3.00E-09)h
8.84E-09
(3.80E-09)h
1.16E-09
(5.00E-10)h
Emission Factor
Range in Ib/ton
(kg/Mg)a
ND - 3.40E-05
(ND-1.70E-05)
4.80E-07 - 4.60E-06
(2.40E-07 - 2.30E-06)
1.46E-06-7.80E-06
(7.30E-07 - 3.90E-06)
ND - 4.80E-07
(ND - 2.40E-07)
2.00E-06 - 3.30E-05
(1.00E-06-1.65E-05)
ND-1.42E-05
(N-7.10E-06)
ND - 2.20E-05
(ND-1.10E-05)
...
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
Reference
Johnson et al., 1990
Johnson et al., 1990
Johnson et al., 1990
Johnson et al., 1990
Johnson et al., 1990
Johnson et al.. 1990
Johnson et al., 1990
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
(continued)
-------
TABLE 4.1.2-9. (Continued)
Control
SCC Number Emission Source Device Pollutant
1-01-002-03 Bituminous Cyclone8 ESP Indeno(l,2,3-cd)pyrene
(continued) (continued) (continued)
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
1 -Methylnaphthalene
2-Methylnaphthalene
Average Emission
Factor in Ib/ton
(kg/Mg)a
6.98E-10
(3.00E-10)h
2.65E-08
(1.14E-08)h
6.75E-09
(2.90E-09)h
2.07E-08
(8.90E-09)h
1.16E-09
(5.00E-10)h
2.70E-08
(1.16E-08)h
3.14E-08
(1.35E-08)h
2.15E-07
(9.26E-08)h
7.77E-08
(3.34E-08)h
1.40E-08
(6.00E-09)h
1.58E-08
(6.80E-09)h
3.74E-08
(1.61E-08)h
Emission Factor Emission
Range in Ib/ton Factor
(kg/Mg)a Rating
D
— D
D
D
D
D
D
D
D
D
D
D
Reference
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup el al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
(continued)
-------
TABLE 4.1.2-9. (Continued)
oo
Control
SCC Number Emission Source Device Pollutant
1-01-002-03 Bituminous Cyclone8 ESP Benzo(e)pyrene
(continued) (continued) (continued)
1-01-002-03 Bituminous Cyclone' Baghouse/ Benz(a)anthracene
SNOXj
Benzo(a)pyrene
Benzo(b+k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Average Emission
Factor in Ib/ton
(kg/Mg)a
2.09E-09
(9.00E-10)h
2.09E-09
(9.00E-10)h
9.30E-10
(4.00E-10)h
3.95E-09
(1.70E-09)h
2.09E-09
(9.00E-10)h
6.98E-10
(3.00E-10)h
9.30E-10
(4.00E-10)h
5.35E-09
(2.30E-09)h
4.19E-09
(1.80E-09)h
3.49E-09
(1.50E-09)h
9.30E-10
(4.00E-10)h
6.98E-09
(3.00E-09)h
Emission Factor Emission
Range in Ib/ton Factor
(kg/Mg)a Rating
D
— D
D
D
D
D
D
D
D
D
D
D
Reference
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
(continued)
-------
TABLE 4.1.2-9. (Continued)
Control
SCC Number Emission Source Device Pollutant
1-01-002-03 Bituminous Cyclone1 Baghouse/ Fluorene
(continued) (continued) SNOXJ
(continued)
Naphthalene
Phenanthrene
Pyrene
1 -Methylnaphthalene
2-Methylnaphthalene
Benzo(e)pyrene
1-01-003-01,06 Lignite Utility Boiler1 Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Average Emission
Factor in Ib/ton
(kg/Mg)a
6.98E-K)
(3.00E-10)h
5.98E-08
(2.57E-08/1
2.42E-08
(1.04E-08)h
1.16E-09
(5.00E-10)h
1.14E-08
(4.90E-09)h
2.00E-08
(8.60E-09)h
1.16E-09
(5.00E-10)h
1.40E-07
(7.00E-08)
6.60E-07
(3.30E-07)
4.00E-07
(2.00E-07)
3.00E-07
(1.50E-07)
2.40E-07
(1.20E-07)
Emission Factor
Range in Ib/ton
(kg/Mg)«
ND
(ND
ND
(ND
ND
(ND
ND
(ND
ND
(ND
—
—
—
—
—
—
—
- 5.80E-07
- 2.90E-07)
- 1.90E-06
- 9.50E-07)
- 1.86E-06
- 9.30E-07)
- 1.38E-06
- 6.90E-07)
- 1.08E-06
- 5.40E-07)
Emission
Factor
Rating Reference
D
D
D
D
D
D
D
D
D
D
D
D
Sverdrup et al.
Sverdrup et al.
Sverdrup et al.
Sverdrup et al.
Sverdrup et al.
Sverdrup et al.
Sverdrup et al.
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
,1994
,1994
,1994
,1994
,1994
,1994
,1994
1990
1990
1990
1990
1990
(continued)
-------
TABLE 4.1.2-9. (Continued)
oo
Control
SCC Number Emission Source Device Pollutant
1-01-003-01,06 Lignite Utility Boiler1' ' Indeno(l,2,3-cd)pyrene
(continued) (continued)
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Phenanthrene
Pyrene
1-Nitropyrene
Benzo(a)fluorene
Benzo(e)pyrene
Dibenz(a,h)acridine
Methylanthracenes
Average Emission
Factor in Ib/ton
(kg/Mg)a
6.40E-07
(3.20E-07)
3.40E-07
(1.70E-07)
1.78E-06
(8.90E-07)
2.80E-07
(1.40E-07)
1.40E-07
(7.00E-08)
4.40E-07
(2.20E-07)
2.80E-06
(1.40E-06)
3.20E-06
(1.60E-06)
3.00E-07
(1.50E-07)
1.46E-06
(7.30E-07)
4.00E-07
(2.00E-07)
1.70E-06
(8.50E-07)
Emission Factor Emission
Range in Ib/ton Factor
(kg/Mg)a Rating
ND-1.18E-06
(ND - 5.90E-07)
ND-1.08E-06
(ND - 5.40E-07)
ND - 7.80E-06
(ND - 3.90E-06)
ND- 1.32E-06
(ND - 6.60E-07)
ND - 3.60E-07
(ND-1.80E-07)
ND-1.86E-06
(ND - 9.30E-07)
ND-1.38E-05
(ND - 6.90E-06)
8.40E-07 - 5.60E-06
(4.20E-07 - 2.80E-06)
ND - 4.80E-07
(ND - 2.40E-07)
ND -8.00E-06
(ND - 4.00E-06)
ND - 7.20E-07
(ND - 3.60E-07)
1.20E-06-1.86E-06
(6.00E-07 - 9.30E-07)
D
D
D
D
D
D
D
D
D
D
D
D
Reference
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
1990
1990
1990
1990
1990
1990
1990
1990
1990
1990
1990
1990
(continued)
-------
TABLE 4.1.2-9. (Continued)
OO
OO
Control
SCC Number Emission Source Device Pollutant
1-01-003-01,06 Lignite Utility Boiler1' ' Triphenylene
(continued) (continued)
1-01-003-02 Pulverized Lignite ESP/Wet Benz(a)anthracene
Tangential Dry FGD"
Bottom"1
Benzo(a)pyrene
Benzo(b+k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Average Emission
Factor in Ib/ton
(kg/Mg)a
4.00E-08
(2.00E-08)
2.09E-09
(9.00E-10)h
9.30E-10
(4.00E-10)h
4.42E-09
(1.90E-09)h
5.35E-09
(2.30E-()9)h
6.98E-10
(3.00E-10)h
6.98E-IO
(3.00E-10)h
1.72E-08
(7.40E-()9)h
1.05E-08
(4.50E-09)h
1.47E-08
(6.30E-09)h
6.98E-10
(3.00E-10)h
4.23E-08
(1.82E-08)h
Emission Factor Emission
Range in Ib/ton Factor
(kg/Mg)a Rating
ND-l.OOE-07 D
(ND - 5.00E-08)
D
D
D
D
D
D
D
D
D
D
D
Reference
Johnson et al., 1990
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
(continued)
-------
TABLE 4.1.2-9. (Continued)
oo
Control
SCC Number Emission Source Device Pollutant
1-01-003-02 Pulverized Lignite ESP/Wet Fluorene
(continued) Tangential Dry FGD"
Bottom1" (continued) (continued)
Naphthalene
Phenanthrene
Pyrene
1 -Methylnaphthalene
2-Methylnaphthalene
Benzo(e)pyrene
Average Emission
Factor in Ib/ton
(kg/Mg)a
4.16E-08
(1.79E-08)h
2.56E-07
(1.10E-07)h
3.14E-07
(1.35E-07)h
1.63E-08
(7.00E-09)h
1.51E-08
(6.50E-09)h
4.09E-08
(1.76E-08)h
1.16E-09
(5.00E-10)h
Emission Factor Emission
Range in Ib/ton Factor
(kg/Mg)a Rating
D
D
D
D
D
D
D
Reference
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup el al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
Sverdrup et al., 1994
ND: Not Detected.
"Emission factors are in Ib (kg) per ton (Mg) of coal fired, unless otherwise noted.
bComposite average emission factors based on six tested bituminous pulverized coal fired wet-bottom utility boilers. Rated capacity range: 376 to 2,834 MMBtu/hr
(110 to
830 MW).
''Four of six tested units ESP controlled, one mechanical precipitator/ESP controlled and one wet scrubber controlled.
dLaboratory analysis was unable to resolve ben/.o(a)pyrene and benzo(e)pyrene.
'Composite average emission factors based on six pulverized bituminous coal fired dry-bottom utility boilers. Rated capacity range: 263 to 1,707 MMBtu/hr
(77 to 500 MW).
fThree of six tested units ESP controlled, two multicyclone/ESP controlled and one wet scrubber controlled.
8Bituminous coal fired cyclone utility boiler with four cyclone burners. Rated capacity: 369 MMBtu/hr (108 MW).
(continued)
-------
TABLE 4.1.2-9. (Continued)
hEmission factors are in Ib (g) per MMBtu (MJ) of heat input.
'Bituminous coal fired cyclone utility boiler with four cyclone burners. Rated capacity: 369 MMBtu/hr (108 MW).
'Testing was conducted during an SNOX demonstration program. The SNOX process combines selective catalytic reduction (SCR) with wet sulfuric acid technologies to
remove nitrogen and sulfur oxides from the flue gas. A slip stream (35 MW) was taken after the air preheater and before the ESP for the demonstration.
''Composite average emission factors based on nine lignite coal fired utility boilers, Five pulverized dry-bottom, two cyclone and two spreader stokers. Rated capacity
range:
68 to 1,434 MMBtu/hr (20 to 420 MW).
'Nine tested units multicyclone or ESP controlled.
""Pulverized lignite coal fired tangential dry-bottom utility boiler. Rated capacity: 3,756 MMBtu/hr (1,100 MW).
"ESP followed by a flue gas desulfurization (FGD) system consisting of four countercurrent spray towers using an alkali slurry.
-------
TABLE 4.1.2-10. PAH EMISSION FACTORS FOR COAL-FIRED INDUSTRIAL
AND COMMERCIAL/INSTITUTIONAL BOILERS
Control
SCC Number Emission Source Device Pollutant
1-02-002-01, Pulverized ' Benzo(a)pyrene
1 -02-002-02 Bituminous Wet
and Dry-Bottom6
Dibenz(a,h)anthracene
Indenof 1 ,2,3-cd)pyrene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Phenanthrene
Pyrene
Bcnzo(e)pyrene
Benzofl uoranthenes
Average Emission
Factor in Ib/ton
(kg/Mg)a
2.80E-07
(1.40E-07)
2.40E-05
(1.20E-05)
5.60E-06
(2.80E-06)
3.60E-06
(1.80E-06)
8.00E-08
(4.00E-08)
4.80E-05
(2.40E-05)
1.68E-05
(8.40E-06)
3.80E-06
(1.90E-06)
7.80E-07
(3.90E-07)
6.20E-04
(3.10E-04)
Emission Factor Range
in Ib/ton
(kg/Mg)a
ND
(ND
ND
(ND
ND
(ND
ND
(ND
ND
(ND
ND
(ND
ND
(ND
- 1.90E-06
- 9.50E-07)
—
—
- 2.20E-05
- 1.10K-05)
- 4.48B-07
- 2.24B-07)
- 3.00E-04
- 1.50Fi-04)
- 1.01E-04
- 5.04E-05)
- 1.24E-05
- 6.20E-06)
- 5.40E-06
- 2.70H-06)
Emission
Factor
Rating Reference
D Johnson el al., 1990
D Johnson etal., 1990
D Johnson etal., 1990
D Johnson etal., 1990
D Johnson el al., 1990
D Johnson etal., 1990
D Johnson etal., 1990
D Johnson etal., 1990
D Johnson etal., 1990
D Johnson etal., 1990
(continued)
-------
TABLE 4.1.2-10. (Continued)
to
Control
SCC Number Emission Source Device Pollutant
1-02-002-04 Bituminous e Benz(a)anthracene
Stoker11
Benzo(a)pyrene
Chrysene
Indeno(l,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Average Emission
Factor in Ib/ton
(kg/Mg)a
8.40E-07
(4.20E-07)
4.60E-05
(2.30E-05)
2.20E-06
(1.10E-06)
1.24E-06
(6.20E-07)
1.94E-04
(9.71E-05)
3.68E-05
(1.84E-05)
4.84E-05
(2.42E-05)
2.20E-05
(1.10E-05)
2.52E-04
(1.26E-04)
4.00E-05
(2.00E-05)
1.93E-03
(9.65E-04)
3.08E-04
(1.54E-04)
Emission Factor Range
in Ib/ton
(kg/Mg)a
—
3.40E-07 - 6.20E-04
(1.70E-07-3.10E-04)
4.40E-07 - 4.60E-06
(2.20E-07 - 2.30E-06)
ND - 5.00E-06
(ND - 2.50E-06)
—
—
—
ND - 2.80E-04
(ND-1.40E-04)
ND - 2.40E-03
(ND-1.20E-03)
ND-1.60E-04
(ND - 8.00E-05)
ND - 7.73E-03
(ND - 3.86E-03)
ND - 3.05E-03
(ND-1.53E-03)
Emission
Factor
Rating Reference
D
D
D
D
D
D
D
D
D
D
D
D
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Suprenant et al
Johnson et al.,
1990
1990
1990
1990
1990
1990
1990
1990
1990
1990
., 1981
1990
(continued)
-------
TABLE 4.1.2-10. (Continued)
Control
SCC Number Emission Source Device Pollutant
1-02-002-04 Bituminous e Pyrene
(continued) Stokerd
(continued)
Benzo(a)fluorene
Benzo(e)pyrene
Benzofluoranthenes
Coronene
Perylene
1-03-002-08 Bituminous None Benz(a)anthracene
Stokerf
Benzo(a)pyrene
Chrysene
Dibenz(a,h)anthracene
Benzo(ghi)perylene
Fluoranthene
Average Emission
Factor in Ib/ton
(kg/Mg)a
2.36E-04
(1.18E-04)
I.90E-06
(9.50E-07)
3.80E-05
(1.90E-05)
1 .46E-06
(7.30E-07)
2.20E-06
(1.10E-06)
6.20E-06
(3.10E-06)
7.39E-03
(3.70E-03)
9.97E-03
(4.98E-03)
1 .23E-03
(6.16E-04)
1 .40E-03
(7.00E-04)
2.69E-03
(1.34E-03)
1.38E-02
(6.92E-03)
Emission Factor Range
in Ib/ton
(kg/Mg)a
ND - 2.90E-03
(ND- 1.45E-03)
ND-7.60E-06
(ND - 3.80E-06)
3.40E-07 - 4.80E-04
(1.70E-07-2.40E-04)
4.40E-07 - 5.00E-06
(2.20E-07 - 2.50E-06)
ND - 2.00E-05
(ND-l.OOE-05)
ND - 9.80E-05
(ND - 4.90E-05)
—
—
—
...
—
Emission
Factor
Rating
D
D
D
D
D
D
E
E
E
E
E
E
Reference
Johnson et al.,
Johnson et al.,
Johnson et al..
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
Johnson et al.,
1990
1990
1990
1990
1990
1990
1990
1990
1990
1990
1990
1990
(continued)
-------
TABLE 4.1.2-10. (Continued)
SCC Number
1-03-002-08
(continued)
Control
Emission Source Device Pollutant
Bituminous None Naphthalene
Stoke/ (continued)
Phenanthrene
Pyrene
Methylphenanthrenes
Average Emission
Factor in Ib/ton
(kg/Mg)a
1.05E-02
(5.24E-03)
1.62E-02
(8.09E-03)
1.39E-02
(6.97E-03)
2.13E-03
(1.06E-03)
Emission Factor Range Emission
in Ib/ton Factor
(kg/Mg)a Rating
E
— E
E
E
Reference
Suprenant et al., 1981
Johnson et al., 1990
Johnson et al., 1990
Johnson et al., 1990
'Emission factors are in Ib (kg) per ton (Mg) of coal fired.
bComposite average emission factors based on seven pulverized bituminous coal fired wet and dry-bottom industrial boilers. Rated capacity range:
116 to 1,251 MMBtu/hr (34 to 366 MW).
cThree of seven tested units ESP controlled, five multicyclone controlled and one FGD unit.
dComposite average emission factors based on 11 bituminous coal fired spreader stokers, five overfeed stokers and one underfeed stoker.
'Eleven units tested. Control configurations included multicyclone, ESP and uncontrolled.
'Bituminous coal fired underfeed stoker. Rated Capacity: 2.2 MMBtu/hr (0.63 MW).
-------
TABLE 4.1.2-11. PAH EMISSION FACTORS FOR OIL-FIRED BOILERS
Average Emission Factor
Emission in Ib/MMBtu
SCC Number Source Control Device Pollutant (g/MJ)a
1-01-004-01 Residual None Benz(a)anthracene
Oil-Fired
Utility Boilerb
Benzo(a)pyrene
Benzo(b)fluoranthene
Q
Benzo(k)fluoranthene
c
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benz(ghi )pery lene
Fluoranthene
Emission Factor Range in
Ib/MMBtu
(g/MJ)a
6.40E-10-1.02E-07
(2.75E-10-4.39E-08)
6.32E-09 - 9.22E-09
(2.72E-09 - 3.96E-09)
6.40E-09 - 3.65E-08
(2.75E-09-1.57E-08)
6.40E-09 - 3.65E-08
(2.75E-09-1.57E-08)
6.40E-09-1.75E-08
(2.75E-09 - 7.52E-09)
6.40E-09 - 2.47E-08
(2.75E-09-1.06E-08)
6.40E-09 - 6.25E-08
(2.75E-09 - 2.69E-08)
6.32E-09-1.02E-07
(2.72E-09 - 4.39E-08)
6.32E-09 - 9.22E-09
(2.72E-09 - 3.96E-09)
6.32E-09 1.43E-08
(2.72E-096.15E-09)
6.40E-09 - 6.95E-08
(2.75E-09 - 2.99E-08)
6.40E-09 - 2.55E-08
(2.75E-09-1.10E-08)
Emission
Factor
Rating
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
Reference
Booth, 1992
Booth, 1992
Booth, 1992
Booth. 1992
Booth, 1992
Booth, 1992
Booth, 1992
Booth, 1992
Booth, 1992
Booth, 1992
Booth, 1992
Booth, 1992
(continued)
-------
TABLE 4.1.2-11. (Continued)
Emission
SCC Number Source Control Device Pollutant
1-01-004-01 Residual None Fluorene
(continued) Oil-Fired
Utility Boilerb
(continued)
Naphthalene
Phenanthrene
Pyrene
1-01-004-01 No. 6 Oil None Benz(a)anthracene
Wall-Fired
Utility Boilerd
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Anthracene
Benz(ghi)perylene
Average Emission Factor
in Ib/MMBtu
(g/MJ)a
c
c
c
c
<1.02E-07
(<4.39E-08)
<4.55E-08
(<1.96E-08)
<2.47E-08
(<1.06E-08)
<6.25E-08
(<2.69E-08)
<2.12E-08
(<9.11E-09)
<1.43E-08
(<6.15E-09)
<6.95E-08
(<2.99E-08)
Emission Factor Range in
Ib/MMBtu
(g/MJ)a
6.40E-09 - 3.15E-08
(2.75E-09-1.35E-08)
4.23E-07-1.21E-05
(1.82E-07-5.20E-06)
6.40E-09-1.08E-07
(2.75E-09 - 4.64E-08)
6.40E-09-3.17E-08
(2.75E-09- 1.36E-08)
—
—
—
—
—
—
Emission
Factor
Rating
NA
NA
NA
NA
D
D
D
D
D
D
D
Reference
Booth, 1992
Booth, 1992
Booth, 1992
Booth, 1992
FIRE*
FIRE8
FIRE*
FIRE*
FIRE*
FIRE*
FIRE*
(continued)
-------
TABLE 4.1.2-11. (Continued)
Emission
SCC Number Source Control Device Pollutant
1-01-004-01 No. 6 Oil None Fluoranthene
(continued) Wall-Fired
Utility Boiled
(continued)
Fluorene
Naphthalene
Phenanthrene
Pyrene
.&. 1-01-004-01 No. 6 Oil Flue Gas Acenaphthene
vb Wall-Fired Recirculation
~J Utility Boiler6
Anthracene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Average Emission Factor
in Ib/MMBtu
(g/MJ)a
<7.78E-08
«3.34E-08)
<1.12E-08
(<4.82E-09)
8.44E-06
(3.63E-06)
<1.08E-07
(<4.64E-08)
<7.07E-08
(<3.04E-08)
4.55E-07
(1.96E-07)
<8.73E-09
«3.75E-09)
<9.41E-09
(<4.05E-09)
2.55E-08
(1.10E-08)
2.67E-06
(1.15E-06)
2.45E-08
(1.05E-08)
Emission Factor Range in Emission
Ib/MMBtu Factor
(g/MJ)a Rating
D
D
D
D
D
D
D
D
D
D
D
Reference
FIRE*
FIRE*
FIRE*
FIRE8
FIRE*
FIREh
FIREh
FIREh
FIREh
FIREh
FIREh
(continued)
-------
TABLE 4.1.2-11. (Continued)
-^
oo
Emission
SCC Number Source Control Device Pollutant
1-01-004-01 No. 6 Oil Flue Gas Pyrene
(continued) Wall-Fired Recirculation
Utility Boiler* (continued)
(continued)
1-01-004-05 No. 5 Flue Gas Chrysene
Oil-Fired Recirculation
Utility Boilerf
Acenaphthene
Acenaphthylene
Anthracene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
Average Emission Factor
in Ib/MMBtu
(g/MJ)a
<8.42E-09
(<3.62E-09)
1.45E-08
(6.23E-09)
4.57E-05
(1.96E-05)
1.85E-08
(7.97E-09)
1.25E-08
(5.37E-09)
5.02E-08
(2.16E-08)
1.45E-07
(6.25E-08)
4.78E-05
(2.06E-05)
1.80E-07
(7.74E-08)
4.75E-08
(2.04E-08)
Emission Factor Range in Emission
Ib/MMBtu Factor
(g/MJ)a Rating
D
D
D
D
D
D
D
D
D
D
Reference
FIREh
FIRE'
FIRE*
FIRE'
FIRE'
FIRE'
FIRE'
FIRE'
FIRE'
FIRE'
(continued)
-------
TABLE 4.1.2-11. (Continued)
VO
Emission
SCC Number Source Control Device Pollutant
1-02-004-01 No. 6 None Chrysene
Oil-Fired
Industrial
Boiler
Benzo(b)fluoranthene
Acenaphthylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
2-Methy 1 naphthalene
1-02-005-01, No. 2 None Benzo(a)pyrene
1-03-005-01 Oil-Fired
Boiler
Fluoranthene
Average Emission Factor
in Ib/MMBtu
(g/MJ)a
1.40E-07
(6.02E-08)
<2.00E-08
(<8.60E-09)
<7.40E-07
«3.18E-07)
<1.90E-07
«8.17E-08)
3.50E-07
(1.50E-07)
2.12E-04
(9.11E-05)
5.10E-07
(2.19E-07)
2.60E-08
(1.12E-08)
9.80E-07
(4.21E-07)
<5.96E-09
(<2.56E-09)
<1.91E-08
«8.20E-09)
Emission Factor Range in Emission
Ib/MMBtu Factor
(g/MJ)a Rating
D
D
D
D
D
D
D
D
D
ND - 3.58E-08 E
(ND- I.54E-08)
ND - 9.54E-08 E
(ND-4.10E-08)
Reference
FIREJ
FIREJ
FIREj
FIREJ
FIRE*
FIREj
HREJ
FIREJ
FIREj
Johnson et al.,
1990
Johnson et al.,
1990
(continued)
-------
TABLE 4.1.2-11. (Continued)
SCC Number
1-02-005-01,
1-03-005-01
(continued)
Emission
Source Control Device Pollutant
No. 2 None Naphthalene
Oil-Fired
Boiler8
(continued)
Pyrene
Average Emission Factor
in Ib/MMBtu
(g/MJ)a
<5.00E-05
(<2.15E-05)
<1.79E-08
(<7.69E-09)
Emission Factor Range in
Ib/MMBtu
(g/MJ)a
ND- 1.50E-04
(ND - 6.45E-05)
ND - 8.34E-08
(ND - 3.59E-08)
Emission
Factor
Rating
E
E
Reference
Suprenant et al.,
1980
Johnson et al.,
1990
NA - Not Applicable.
ND - Not Detected.
"Emission factors are in Ib (g) per MMBtu (MJ) of heat input.
Multiple units tested. Boiler design: front or opposed fired. Rated capacity range: 188 to 2,523 MMBtu/hr(55 to739MW).
°Data not available to calculate mean emission factor. Median emission factor may be used.
d598 MMBtu/hr (175 MW) wall-fired utility boiler operated at nominal full load during testing.
el ,639 MMBtu/hr (480 MW) wall-fired utility boiler operated at nominal full load during testing.
*785 MMBtu/hr (230 MW) utility boiler operated over a range of load conditions during testing.
gBell, Arlene C., and Booth, Richard B. Emissions Inventory Testing at El Segundo Generating Station Unit 1. Prepared for Southern California Edison
Company, Rosemead, California. For Inclusion in Air Toxics Hot Spots Inventory Required under AB-2588. CARNOT, Tustin, California. ESR 53304-2052.
April 1990.
hMcDannel, Mark D. and Green, Lisa A. Air Toxics Emissions Inventory Testing at Alamitos Unit 5. Prepared for Southern California Edison Company,
Rosemead, California. For Inclusion in Air Toxics Hot Spots Inventory Required under AB-2588. CARNOT, Tustin, California. ESR 53304-2053. May 1990.
'Air Toxics "Hot Spots" Source Testing of a Utility Boiler, May 1991. (Confidential Report No. ERC-17).
JAB 2588 Testing of an Industrial Boiler at a Creamery, March 5 through 22, 1990. (Confidential Report No. ERC-65).
-------
TABLE 4.1.2 12. PAH EMISSION FACTORS FOR OIL-FIRED PROCESS HEATERS
Control
SCC Number Emission Source Device Pollutant
3-10-004-02 Residual None Benz(a)anthracene
Oil-Fired Pipeline
Heater
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Anthracene
Benz(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
Average Emission
Factor in Ib/MMBtu
(g/MJ)a
<5.51E-05
(<2.37E05)
<1.07E-05
(<4.60E-06)
7.72E-06
(3.32E-06)
5.10E-06
(2.19E-06)
<1.52E-05
(<6.54E-06)
1.38E-05
(5.93E-06)
3.21E-05
(1.38E-05)
1.96E-04
(8.43E-05)
2.71E-04
(1.17E-04)
3.38E-04
(1.45E-04)
9.46E-05
(4.07E-05)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
Reference
FIREb
FlREb
FIREb
FlREb
FIREb
FIREb
FIREb
FIREb
FIREb
FIREb
FIRE"
"Emission factors are in Ib (g) per MMBtu (MJ) of heat input.
''Emissions Inventory Testing at Huntington Beach Generating Station Fuel Oil Heater No. 2. Prepared for Southern California
Edison Company, Rosemead, California. CARNOT.May 1990.
-------
TABLE 4.1.2-13. PAH EMISSION FACTORS FOR WASTE OIL COMBUSTION
o
ro
Control
SCC Number Emission Source Device Pollutant
1-05-001-14, Space Heater- None Benz(a)anthracene/Chrysene
1 -05-002- 1 4 Vaporizing Burner
Benzo(a)pyrene
Benzofluoranthenes
Acenaphthylene
Anthracene/Phenanthrene
Fluorene
Naphthalene
Pyrene
Benzo(e)pyrene
Perylene
1-05-001-13, Space Heater- None Benz(a)anthracene
1 -05-002- 1 3 Atomizing Burner
Benzo(a)pyrene
Average Emission
Factor in
lb/1000 gal
(kg/1000 l)a
4.0E-03
(4.8E-04)
4.0E-03
(4.8E-04)
4.02E-04
(4.83E-05)
1.34E-04
(1.61E-05)
1.10E-02
(1.3E-03)
4.42E-04
(5.31E-05)
1.30E-02
(1.6E-03)
7.1E-03
(8.4E-04)
7.37E-04
(8.85E-05)
4.02E-04
(4.83E-05)
3.52E-05
(4.22E-06)
5.86E-05
(7.04E-06)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
Reference
U.S. EPA, 1995c
U.S. EPA. 1995c
Cooke et al., 1984
Cookeetal., 1984
U.S. EPA, 1995c
Cooke et al., 1984
U.S. EPA, 1995c
U.S. EPA, 1995c
Cookeetal., 1984
Cookeetal., 1984
Cookeetal., 1984
Cooke et al., 1984
(continued)
-------
TABLE 4.1.2-13. (Continued)
o
U)
Control
SCC Number Emission Source Device Pollutant
1-05-001-13, Space Heater- None Chrysene
1 -05-002- 1 3 Atomizing Burner
(continued) (continued)
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Anthracene/Phenanthrene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Pyrene
Anthanthrene
Benzo(e)pyrene
Average Emission
Factor in
Ib/lOOOgal
(kg/1000 l)a
3.52E-05
(4.22E-06)
4.69E-05
(5.63E-06)
2.93E-05
(3.52E-06)
l.OE-04
(1.2E-05)
4.11E-05
(4.93E-06)
5.82E-05
(6.34E-06)
8.80E-05
(1.06E-05)
9.2E-05
(1.1E-05)
8.3E-06
(9.95E-07)
1.17E-05
(1.41E-06)
2.93E-06
(3.52E-07)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
Reference
Cookeetal., 1984
Cookeetal., 1984
Cooke et al., 1984
U.S. EPA. 1995c
Cookeetal., 1984
Cooke et al., 1984
Cooke et al., 1984
U.S. EPA, 1995c
U.S. EPA, 1995c
Cooke et al., 1984
Cookeetal., 1984
(continued)
-------
TABLE 4.1.2-13. (Continued)
SCC Number
1-05-001-13,
1-05-002-13
(continued)
Control
Emission Source Device Pollutant
Space Heater - None Coronene
Atomizing Burner
(continued)
Perylene
Average Emission
Factor in
Ib/lOOOgal
(kg/1000 1)4
5.86E-06
(7.04E-07)
3.52E-05
(4.22E-06)
Emission
Factor
Rating
D
D
Reference
Cookeetal.. 1984
Cookeetal., 1984
"Emission factors are in Ib (kg) per 1,000 gal (1,000 1) of waste oil fired.
-------
SECTION 4.1.2 REFERENCES
Baladi.E. Stationary Source Testing of Bagasse-fired Boilers at the Hawaiian Commercial and Sugar
Company. Puunene. Maui. Hawaii. MRI Report Number 3927-C( 12). Midwest Research Institute,
Kansas City, Missouri. February 1976.
Booth, R. B., and M. D. McDannel. "Summary of Air Toxic Emission Values for Utility Boilers Firing
Residual Fuel Oil or Natural Gas." Presented at the 85th Annual Air and Waste Management
Association Meeting and Exhibition, Kansas City, Missouri. 14 p. June 21-26,1992.
Cooke, M. et al. Waste Oil Heaters: Organic. Inorganic, and Bioassav Analyses of Combustion Samples.
EPA Report No. 600/D-84-130. U.S. Environmental Protection Agency, Research Triangle Park, North
Carolina. May 1984.
Hubbard, A.J. Hazardous Air Emissions Potential from a Wood-Fired Furnace. Wisconsin Department
of Natural Resources, Bureau of Air Management, Madison, Wisconsin. 1991.
Johnson, N.D., M.T. Scholtz, V. Cassaday, and K. Davidson. MOE Toxic Chemical Emission Inventory
for Ontario and Eastern North America. Prepared for the Air Resources Branch, Ontario Ministry of the
Environment, Rexdale, Ontario. Draft Report No. P.89-50-5429/OG. pp. 110-130. 1990.
Kelly, M.E. Sources and Emissions of Polycyclic Organic Matter. U.S. Environmental Protection
Agency, Research Triangle Park, North Carolina. Report No. 450/5-83-0lOb. pp. 5-9 to 5-44. 1983.
Mead, R.C., G.W. Brooks, and B.K. Post. Summary of Trace Emissions from and Recommendations of
Risk Assessment Methodologies for Coal and Oil Combustion Sources. Prepared for U.S. Environmental
Protection Agency, Pollutant and Assessment Branch, Research Triangle Park, North Carolina. EPA
Contract No. 68-02-3889, Work Assignment 41. July 1986.
National Council of the Paper Industry for Air and Stream Improvement (NCASI). A Polycyclic Organic
Materials Emissions Study for Industrial Wood-fired Boilers. NCASI Technical Bulletin No. 400. New
York, New York. May 1983.
Sassenrath, C. P. Air Toxic Emissions from Wood-Fired Boilers. In: Proceeding of the 1991 TAPPI
Environmental Conference, pp. 483-491. 1991.
Shih, C.C. et al. Emissions Assessment of Conventional Stationary Combustion Systems - Volume HI:
External Combustion Sources for Electricity Generation. Prepared for U.S. Environmental Protection
Agency, Office of Research and Development, Washington, DC. EPA-600/7-81-003a. pp. 455.
November 1980.
Surprenant, N.F., W. Battye, D. Roeck, and S.M. Sandberg. Emissions Assessment of Conventional
Stationary Combustion Systems. Volume V: Industrial Combustion Sources. Prepared for
U.S. Environmental Protection Agency, Office of Research and Development, Washington, DC. 178 p.
April 1981.
4-105
-------
Surprenant, N.F., P. Hung, R. Li, K.T. McGregor, W. Piispanen, and S.M. Sandberg. Emissions
Assessment of Conventional Stationary Combustion Systems. Volume IV: Commercial/Institutional
Combustion Sources. Prepared for U.S. Environmental Protection Agency, Office of Research and
Development, Washington, DC. 192 p. June 1980.
Sverdrup, G.M. et al. 'Toxic Emissions from a Cyclone Burner Boiler with an ESP and with the SNOX
Demonstration and from a Pulverized Coal Burner Boiler with an ESP/Wet Flue Gas Desulfurization
System." Presented at the 87th annual meeting and exhibition of the Air and Waste Management
Association, Cincinnati, Ohio, June 19-24, 1994.
U.S. Environmental Protection Agency. ICCR Inventory Database Version 3.0. Office of Air Quality
Planning and Standards, Research Triangle Park, North Carolina. 1998. ICCR Internet Website:
www.epa.gov/ttn/iccr/icl.html. March 1998.
U.S. Environmental Protection Agency. Locating and Estimation Air Emissions from Sources of Dioxins
and Furans. Office of Air Quality Planning and Standards, Emission Inventory Branch, Research
Triangle Park, North Carolina. EPA-454/R-97-003. 1997.
U.S. Environmental Protection Agency. Compilation of Air Pollutant Emissions Factors. Volume I:
Stationary Point and Area Sources. AP-42, Fifth Edition, Section 1.1: Bituminous and Subbituminous
Coal Combustion. Office of Air Quality Planning and Standards, Research Triangle Park, North
Carolina. 1995a.
U.S. Environmental Protection Agency. Compilation of Air Pollutant Emissions Factors. Volume I:
Stationary Point and Area Sources. AP-42, Fifth Edition, Section 1.2: Anthracite Coal Combustion.
Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina. 1995b.
U.S. Environmental Protection Agency. Compilation of Air Pollutant Emissions Factors. Volume I:
Stationary Point and Area Sources. AP-42, Fifth Edition, Section 1.11: Waste Oil Combustion. Office
of Air Quality Planning and Standards, Research Triangle Park, North Carolina. 1995c.
U.S. Environmental Protection Agency. Factor Information Retrieval (FIRE') System Database.
Version 5. la. Office of Air Quality, Planning, and Standards, Emission Factor and Inventory Group.
Research Triangle Park, North Carolina. September 1995d.
U.S. Environmental Protection Agency. Alternative Control Techniques Document - NOX Emissions
from Utility Boilers. Office of Air Quality Planning and Standards, Research Triangle Park, North
Carolina. EPA-453/R-94-023. March 1994a.
U.S. Environmental Protection Agency. Compilation of Air Pollutant Emissions Factors. Volume I:
Stationary Point and Area Sources. AP-42, Fifth Edition, Section 1.6: Wood Waste Combustion in
Boilers. U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Research
Triangle Park, North Carolina. 1994b.
4-106
-------
U.S. Environmental Protection Agency. Background Information Document for Industrial Boilers.
Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina.
EPA-450/3-82-006a. pp. 3-1 to 3-19. March 1982.
4-107
-------
4.2 STATIONARY INTERNAL COMBUSTION
Stationary internal combustion (1C) sources are grouped into two categories:
reciprocating engines and gas turbines. POM emissions primarily result from the incomplete
combustion of the gasoline, diesel, or natural gas fuel that is burned in these engines and
turbines. The principal application areas for stationary 1C engines and turbines are electricity
generation and industrial applications such as oil and gas transmission, natural gas processing,
and oil and gas production and exploration (Shih et al., 1979). The use of stationary 1C engines
is so widespread that source locations are not listed in this document (U.S. EPA, 1995).
4.2.1 Reciprocating Engines
The first group of stationary 1C sources, reciprocating engines, may be classified
into two types: spark and compression ignition (diesel), but all reciprocating 1C engines operate
by the same basic process shown in Figure 4.2-1. A combustible mixture is first compressed in a
small volume between the head of a piston and its surrounding cylinder. The mixture is then
ignited, and the resulting high pressure products of combustion push the piston through the
cylinder. This movement is converted from linear to rotary motion by a crankshaft. The piston
returns, pushing out exhaust gases, and the cycle is repeated (U.S. EPA, 1995).
Process Description-Diesel Engines
In compression ignition engines, more commonly known as diesel engines,
combustion air is first compression heated in the cylinder, and fuel is then injected into the hot
air. Ignition is spontaneous as the air is above the auto-ignition temperature of the fuel. All
distillate oil reciprocating engines are compression-ignited (U.S. EPA, 1995).
4-108
-------
Intake
Compression
Exhaust
Figure 4.2-1. Operating Cycle of a Conventional Reciprocating Engine
Source: Flagan and Seinfeld, 1988.
-------
Diesel engines usually operate at a higher compression ratio (ratio of cylinder
volume when the piston is at the bottom of its stroke to the volume when it is at the top) than
spark-ignited engines because fuel is not present during compression; hence, there is no danger
of premature auto-ignition. Because engine thermal efficiency rises with increasing pressure
ratio (and pressure ratio varies directly with compression ratio), diesel engines are more efficient
than spark-ignited ones. This increased efficiency is gained at the expense of poorer response to
load changes and a heavier structure to withstand the higher pressures (U.S. EPA, 1995).
The primary domestic use of large stationary diesel engines (greater than 600 hp
[447 kW]) is in oil and gas exploration and production. These engines, in groups of three to five,
supply mechanical power to operate drilling (rotary table), mud pumping and hoisting equipment,
and may also operate pumps or auxiliary power generators. Another frequent application of large
stationary diesels is electricity generation for both base and standby service. Smaller uses of
large diesel engines include irrigation, hoisting and nuclear power plant emergency cooling water
pump operation. The category of smaller diesel engines (up to 600 hp [447 kW]) covers a wide
variety of industrial applications such as aerial lifts, fork lifts, mobile refrigeration units,
generators, pumps, industrial sweepers/scrubbers, material handling equipment (such as
conveyors), and portable well-drilling equipment. The rated power of these engines can be up to
250 hp (186 kW), and substantial differences in engine duty cycles exist (U.S. EPA, 1995).
Emission Factors—Diesel Engines
Most of the pollutants from 1C engines are emitted through the exhaust.
However, some hydrocarbons escape from the crankcase as a result of blow-by (gases that are
vented from the oil pan after they have escaped from the cylinder past the piston rings) and from
the fuel tank and carburetor because of evaporation. Nearly all of the hydrocarbons from diesel
engines enter the atmosphere from the exhaust. Crankcase blow-by is minor because
hydrocarbons are not present during compression of the charge. Evaporative losses are
insignificant in diesel engines due to the low volatility of diesel fuels. In general, evaporative
losses are also negligible in engines using gaseous fuels because these engines receive their fuel
continuously from a pipe rather than via a fuel storage tank and fuel pump (U.S. EPA, 1995).
4-110
-------
Available emission factors for PAH from small uncontrolled industrial,
commercial, and institutional diesel-fired 1C engines ares shown in Table 4.2-1. Emission
factors for PAH from large stationary diesel engines (so-called "large-bore" engines) are shown
as well (U.S. EPA, 1995). It must be noted that emissions can vary significantly from one engine
to the next depending on its design and duty cycle.
Control measures for large stationary diesel engines to date have been directed
mainly at limiting NOX emissions, because NOX is the primary pollutant from this group of 1C
engines. All of these controls are engine control techniques except for the selective catalytic
reduction (SCR) technique, which is a post-combustion control. As such, all of these controls
usually affect the emissions profile for the other pollutants such as PAH as well. The
effectiveness of controls on an particular engine will depend on the specific design of each
engine and the effectiveness of each technique could vary considerably. Other NOX control
techniques exist and include internal/external exhaust gas recirculation (EGR), combustion
chamber modification, manifold air cooling, and turbocharging. Various other emission
reduction technologies may be applicable to the smaller diesel and gasoline engines. These
technologies are categorized into fuel modifications, engine modifications, and exhaust
after-treatments (U.S. EPA, 1995).
Process Description—Gasoline Engines
The other type of engine, spark ignition, initiates combustion by the spark of an
electrical discharge. The fuel may be mixed with the air in a carburetor, or the fuel can be
injected into the compressed air in the cylinder. All gasoline reciprocating engines are
spark-ignited. Gasoline engines up to 600 hp (447 kW) can be used interchangeably with diesel
1C engines in the same industrial applications described previously. As with diesel engines,
substantial differences in gasoline engine duty cycles exist, and emission profiles may be
expected to differ as well (U.S. EPA, 1995). No emission factors for gasoline-fired stationary 1C
engines were identified.
4-111
-------
TABLE 4.2-1. PAH EMISSION FACTORS FOR STATIONARY DIESEL
INTERNAL COMBUSTION ENGINES - RECIPROCATING
SCC Number Emission Source Control Device Pollutant
2-02-001-02, Industrial, Commercial, and Uncontrolled Benz(a)anthracene
2-03-001-01 Institutional Engines
Benzo(a)pyrene
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Average Emission
Factor in Ib/MMBtu
(g/MJ)»
1.68E-06
(7.21E-07)
<1.88E-07
(<8.07E-08)
<1.55E-07
(<6.65E-08)
3.53E-07
(1.51E-07)
<5.83E-07
(<2.50E-07)
<3.75E-07
(<1.61E-07)
<1.24E-06
(<6.09E-07)
<5.06E-06
(<2.10E-06)
1.87E-06
(8.02E-07)
<4.89E-07
(<2.10E-07)
7.61E-06
(3.26E-06)
2.92E-05
(1.25E-05)
Emission Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.2-1. (Continued)
SCC Number Emission Source Control Device Pollutant
2-02-001-02, Industrial, Commercial, and Uncontrolled Benzo(b)fluoranthene
2-03-001-01 Institutional Engines (continued)
(continued) (continued)
2-02-004-01 Industrial Large Bore Uncontrolled Benz(u)anthracene
Engine
Benzo(a)pyrene
Benzo(k)fluoranthene
Chrysene
Diben /(a,h)anthracene
Indeno(l ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Average Emission
Factor in Ib/MMBtu
(g/MJ)a
<9.91E-08
(<4.25E-08)
6.22E-07
(2.67E-07)
<2.57E-07
(<1.10E-07)
<2.18E-07
(<9.35E-08)
1.53E-06
(6.56E-07)
<3.46E-07
(<1.48E-07)
<4.14E-07
(<1.78E-07)
4.68E-06
(2.01E-06)
9.23E-06
(3.96E-06)
1.23E-06
(5.28E-07)
<5.56E-07
(<2.39E-07)
4.03E-06
(1.73E-06)
Emission Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.2-1. (Continued)
SCC Number Emission Source
2-02-004-01 Industrial Large Bore
(continued) Engine (continued)
Control Device Pollutant
Uncontrolled Fluorene
(continued)
Naphthalene
Phenanthrene
Pyrene
Benzo(b)fluoranthene
Average Emission
Factor in Ib/MMBtu
(R/MJ)a
1.28E-05
(5.49E-05)
0.00013
(5.58E-05)
4.08E-05
(1.75E-05)
3.71E-06
(1.59E-06)
1.11E-06
(4.76E-07)
Emission Factor
Rating
E
E
E
E
E
'Emission factors in Ib/MMBtu (g/MJ) of heat input.
Source: U.S. EPA, 1995.
-------
Process Description-Natural Gas Engines
Most reciprocating 1C engines that use natural gas are of the spark-ignited type.
As with gasoline engines, the gas is first mixed with the combustion air at an intake valve, but
the fuel may also be injected into the compressed air in the cylinder. Natural gas can be used in a
compression ignition engine but only if a small amount of diesel fuel is injected into the
compressed air/gas mixture to initiate combustion, hence the name dual-fuel engine. Dual-fuel
engines were developed to obtain compression ignition performance and the economy of natural
gas, using a minimum of 5 to 6 percent diesel fuel to ignite the natural gas. Large dual-fuel
engines have been used almost exclusively for prime electric power generation
(U.S. EPA, 1995).
Natural gas-fired stationary 1C engines are also used in the natural gas industry
primarily to power compressors used for pipeline transportation, field gathering (collecting gas
from wells), underground storage, and gas processing plant applications, collectively referred to
as prime movers. Pipeline engines are concentrated in the major gas-producing states (such as
those along the Gulf Coast) and along the major gas pipelines (U.S. EPA, 1995).
Reciprocating 1C engines used in the natural gas industry are separated into three
design classes: two-stroke lean bum, four-stroke lean burn, and four-stroke rich burn.
Two-stroke engines complete the power cycle in a single engine revolution compared to two
revolutions for four-stroke engines. Four-stroke engines use a separate engine revolution for the
intake/compression stroke and the power/exhaust stroke. Both types of engines may be
turbocharged using an exhaust-powered turbine to pressurize the charge for injection into the
cylinder (U.S. EPA, 1995). Rich-burn engines operate near the fuel/air stoichiometric limit with
exhaust excess oxygen levels less than 4 percent. Lean-burn engines may operate up to the lean
flame extinction limit, with exhaust oxygen levels of 12 percent or greater (U.S. EPA, 1995).
Pipeline population statistics show a nearly equal installed capacity of
reciprocating 1C engines and gas turbines (which are discussed in Section 4.2.2). For
4-115
-------
reciprocating engines, two-stroke designs contribute approximately two-thirds of installed
capacity in this industry (U.S. EPA, 1995).
Emission Factors—Natural Gas Engines
Emission factors for PAH from two uncontrolled natural gas-fired reciprocating
engines—one two-stroke and one four-stroke-are listed in Table 4.2-2 (Meeks, 1992).
Because NOX is the primary pollutant of significance emitted from natural
gas-fired engines, control measures to date have been directed mainly at limiting NOX emissions.
Here again, the NOX control measures often affect the emissions of other pollutants, and not
always positively. New applications of dry low NOX combustor can designs and selective
catalytic reduction (SCR) are appearing (U.S. EPA, 1995).
4.2.2 Gas Turbines
Process Description
The second group of stationary internal combustion sources, gas turbines, are so
named not because they are gas-fired, but because combustion exhaust gas drives the turbine.
Unlike the reciprocating engines, the gas turbine operates in steady flow. As shown in
Figure 4.2-2, a basic gas turbine consists of a compressor, a combustor, and a turbine.
Combustion air enters the turbine through a centrifugal compressor, where the pressure is raised
to 5 to 30 atm, depending on load and the design of the engine. Part of the air is then introduced
into the primary combustion zone, into which fuel is sprayed and burns in an intense flame. The
gas volume increases with combustion, so as the gases pass at high velocity through the turbine,
they generate more work than is required to drive the compressor. This additional work is
delivered by the turbine to a shaft, to drive an electric power generator or other machinery
(Flagan and Seinfeld, 1988).
4-116
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TABLE 4.2-2. PAH EMISSION FACTORS FOR STATIONARY NATURAL GAS-FIRED
INTERNAL COMBUSTION ENGINES - RECIPROCATING
SCC Number Emission Source Control Device Pollutant
2-02-002-52 Two-Cycle Lean Burn Uncontrolled Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzc )(k)fluoranthene
Chrysene
Diben z(a,h)anthracene
Indeno(l ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Pluoranthene
Average Emission
Factor in Ib/MMCF
(kg/MMm3)*
4.10E-04
(6.54E-03)
4 16E-04
(6 64E-03)
7.30E-05
(1.16E-03)
256E-03
(0.0408)
8.04E-04
(0.0128)
3.68E-05
(5.87E-04)
6.40E-05
(1.02E-03)
3.38E-04
(5.39E-03)
5.00E-03
(0.0798)
2.07E-03
(0.0330)
4.44E-05
(7.08E-04)
8.32E-05
0.33E-03)
Emission Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.2-2. (Continued)
oo
SCC Number Emission Source Control Device Pollutant
2-02-002-52 Two-Cycle Lean Burn Uncontrolled Fluorene
(continued) (continued) (continued)
Naphthalene
Phenanthrene
Pyrene
2-02-002-53 Four-Cycle Rich Hum Uncontrolled Ben/(a)anthracene
Ben/o(a)pyrene
Ben/o(b)fluoranthene
Ben/o(k)fluoranthene
Chrysene
Dibc nz(a,h)anthracene
Indeno(l,2,3-cd)pyrene
Acenaphthene
Average Emission
Factor in Ib/MMCF
(kR/MMm3)a
l.HE-03
(0.0177)
0.111
(1.77)
2.29E-03
(0.0365)
1.16E-04
(1.85E-03)
7.47E-05
(1.19E-03)
3.42E-05
(5.45E-04)
2.91E-04
(4.64E-03)
5.24E-04
(8.36E-03)
9.20E-05
(1.47E-03)
1.03E-05
(1.64E-04)
1.15E-04
(1.83E-03)
6.92E-04
(0.01 10)
Emission Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.2-2. (Continued)
SCC Number Emission Source Control Device Pollutant
2-02-002-53 Four-Cycle Rich Burn Uncontrolled Acenaphthylene
(continued) (continued) (continued)
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
Average Emission
Factor in Ib/MMCF
(kg/MMm3)4
7.42E-03
(0.118)
2 46E-04
(3 92E-03)
9.94E-05
(1.59E-03)
2 39E-04
(3 81E-03)
4.43E-04
(707E-03)
0.117
(1.87)
8 57E-04
(0.0137)
1.17E-04
(1 87E-03)
Emission Factor
Rating
E
E
E
E
E
E
E
E
'Emission factors in Ib per million cubic feet, Ih/MMCF (kg per million cubic meters, kg/MMm3) of natural gas fired.
Source: Meeks, 1992.
-------
Combustion
chamber
Compressor
Fuel
Air
Turbine
*-Net work
£
3
Figure 4.2-2. Gas Turbine Engine Configuration
Source: Plagan and Seinfeld, 1988.
-------
Gas turbines may be classified into three general types: simple open cycle,
regenerative open cycle, and combined cycle. In the simple open cycle, the hot gas discharged
from the turbine is exhausted to the atmosphere. In the regenerative open cycle, the gas
discharged from the turbine is passed through a heat exchanger to preheat the combustion air.
Preheating the air increases the efficiency of the turbine. In the combined cycle, the gas
discharged from the turbine is used as auxiliary heat for a steam cycle. Regenerative-type gas
turbines constitute only a very small fraction of the total gas turbine population. Identical gas
turbines used in the combined cycle and in the simple cycle tend to exhibit the same emissions
profiles. Therefore, usually only emissions from simple cycles are evaluated (Shih et al., 1979).
The same fuels used in reciprocating engines are combusted to drive gas turbines.
The primary fuels used are natural gas and distillate (No. 2) fuel oil, although residual fuel oil is
used in a few applications (U.S. EPA, 1995). The liquid fuel used must be similar in volatility to
diesel fuel to produce droplets that penetrate sufficiently far into the combustion chamber to
ensure efficient combustion even when a pressure atomizer is used (Flagan and Seinfeld, 1988).
Stationary gas turbines are applied in electric power generators, in gas pipeline
pump and compressor drives, and in various process industries. Gas turbines [greater than
3 MW(e)] are used in electrical generation for continuous, peaking, or standby power
(U.S. EPA, 1995). In 1990, the actual gas-fired combustion turbine generating capacity for
electric ultilities was 8,524 MW (NAERC, 1991). The current average size of electricity
generation gas turbines is approximately 31 MW. Turbines are also used in industrial
applications, but information was not available to estimate their installed capacity.
Emission Factors
Emission control technologies for gas turbines have advanced to a point where all
new and most existing units are complying with various levels of specified emission limits.
Today most gas turbines are controlled to meet local, State, and/or Federal regulations. For these
sources, emission factors have become an operational specification rather than a parameter to be
quantified by testing (U.S. EPA, 1995). As with reciprocating engines, the primary pollutant
4-121
-------
from gas turbines is NOX, and techniques for its control still have ramifications for the emissions
profiles of other pollutants such as PAHs. Available PAH emission factors for diesel- and
natural gas-fired gas turbines are listed in Table 4.2-3 (Carnot, 1989; Carnot, 1990;
U.S. EPA, 1995).
Water/steam injection is the most prevalent NOX control for co-generation/
combined cycle gas turbines. The water or steam is injected with the air and fuel into the turbine
combuster in order to lower the peak temperatures, which in turn decreases the thermal NOX
produced. The lower average temperature within the combustor can may produce higher levels
of CO and hydrocarbons as a result of incomplete combustion (U.S. EPA, 1995). SCR systems
can be used also, all existing applications of SCR have been used in conjunction with
water/steam injection controls (U.S. EPA, 1995).
4-122
-------
TABLE 4.2-3. PAH EMISSION FACTORS FOR STATIONARY INTERNAL COMBUSTION ENGINES - GAS TURBINES
SCC Number
2-01-001-01
2-01-001-01
2-01-002-01
Emission Source
Electric Generation,
Diesel-Fired
Electric Generation,
Diesel-Fired
Electric Generation, Natural
Gas-Fired
Control Device Pollutant
Afterburner Anthracene
Fluorene
Phenanthrene
Steam or Water Phenanthrene
Injection
Selective Naphthalene
Catalytic
Reduction
Average Emission Factor
in Ib/MMBtu
(R/MJ)a
<3.43E-08
(<1.47E-08)
<2.56E-08
(<1.10E-08)
<5.87E-08
(<2.52E-08)
<2.69E-08
(<1.15E-08)
<4.9E-05
(<2.10E-05)
Emission
Factor
Rating
E
E
E
E
E
Reference
Carnot, 1990
Camot, 1990
Carnot, 1990
Carnot, 1989
U.S. EPA, 1995
'Emission factors in Ib/MMBtu (g/MJ) of heat input.
-------
SECTION 4.2 REFERENCES
Carnot, Inc. Air Toxics Emissions Inventory Testing at Coolwater Generating Stationary
Combustion Turbine No. 42. Prepared for Southern California Edison Company, Rosemead
California for inclusion in Air Toxics Hot Spots Inventory Required under AB-2588. ESR
53304-2054. May 1990.
Carnot, Inc. Emissions Inventory Testing at Long Beach Combustion Turbine No. 3. Prepared
for Southern California Edison Company, Rosemead California for inclusion in Air Toxics Hot
Spots Inventory Required under AB-2588. ESR 53304-2050. May 1989.
Meeks, H.N. "Air Toxics Emissions From Gas-Fired Engines." Journal of Petroleum
Technology, pp. 840-845. July, 1992.
Flagan, R.C., and J.H. Seinfeld. Fundamentals of Air Pollution Engineering. Prentice-Hall, Inc.,
Englewood Cliffs, New Jersey, pp. 280-285. 1988.
North American Electric Reliability Council (NAERC). Electricity Supply and Demand 1991-
2000. Princeton, NJ. p. 34. July, 1991.
Shih, C.C., J.W. Hamersma, D.G. Ackerman, R.G. Beimer, M.L. Kraft, and M.M. Yamada.
Emissions Assessment of Conventional Stationary Combustion Systems. Volume n.' Internal
Combustion Sources. U.S. Environmental Protection Agency, Industrial Environmental
Research Laboratory, Research Triangle Park, North Carolina. EPA-600/7-79-029c. pp. 1-2.
February 1979.
U.S. Environmental Protection Agency. Compilation of Air Pollutant Emission Factors.
Volume I: Stationary Point and Area Sources. AP-42, Fifth Edition. Office of Air Quality
Planning and Standards, Research Triangle Park, North Carolina, pp. 3.1-1 to 3.4-9. 1995.
4-124
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4.3 WASTE INCINERATION
4.3.1 Municipal Waste Combustion
Process Description
Municipal waste combustors (MWCs) burn garbage and other nonhazardous solid
waste, commonly called municipal solid waste (MSW). Three main design types of technologies
are used to combust MSW: mass burn, refuse-derived fuel-fired (RDF), and modular
combustors.
Mass Burn Combustors--In mass burn units, the MSW is combusted without any preprocessing
other than removal of items too large to go through the feed system. In a typical mass burn
combustor, refuse is placed on a grate that moves through the combustor. Combustion air in
excess of stoichiometric amounts is supplied both below (underfire air) and above (overfire air)
the grate. Mass burn combustors are usually erected at the site (as opposed to being prefabricated
at another location), and range in size from 50 to 1,000 tons/day (46 to 900 Mg/day) of MSW
throughput per unit. Mass burn combustors can be divided into mass burn/waterwall (MBAVW),
mass burn/rotary waterwall combustor (MB/RC), and mass burn refractory wall (MB/REF)
designs.
MBAVW combustor walls are constructed of metal tubes that contain pressurized
water and recover radiant heat for production of steam and/or electricity. A typical MBAVW
combustor is shown in Figure 4.3.1-1. With the MB/RC, a rotary combustion chamber sits at a
slight angle and rotates at about 10 revolutions per hour, causing the waste to advance and
tumble as it burns. The combustion cylinder consists of alternating water tubes and perforated
steel plates. An MB/RC combustor normally operates at about 50 percent excess air.
Figure 4.3.1-2 illustrates a simplified process flow diagram for a MB/RC. MB/REF designs are
older and typically do not include any heat recovery. One type of MB/REF combustor is shown
in Figure 4.1.3-3.
4-125
-------
B*H
Convayor
Total
A»h
Dteclurg*
Figure 4.3.1-1. Typical Mass Burn Waterwall Combustor
Source: U.S. EPA, 1993.
-------
Superheater
\
Convection
Section
Economize
Flue
Gat
Figure 4.3.1-2. Simplified Process Flow Diagram, Gas Cycle for a Mass Burn/Rotary Waterwall Combustor
Source: U.S. EPA. 1993.
-------
Stack
Emergency
Stack
Air
Pollution
Control
Device
f
t—*
oo
Waste Tipping Roor
Forced Overfire Vibrating
Draft Air Conveyor
Fan Fan 'or B
Ash
Ash
SpTays9 Cooling Conveyors
Bottom Chamber
Quench conveyor
Figure 4.3.1-3. Mass Burn Refractory-Wall Combustor with Grate/Rotary Kiln
Source: U.S. EPA, 1993.
-------
RDF-fired Combustors—RDF combustors burn processed waste that varies from shredded waste
to finely divided fuel suitable for co-firing with pulverized coal. Combustor sizes range from
320 to 1,400 tons/day (290 to 1,300 Mg/day). There are three major types of RDF-fired
combustors: (1) dedicated RDF combustors, which are designed to burn RDF as a primary fuel,
(2) coal/RDF co-fired, and (3) fluidized-bed combustors (FBCs) where waste is combusted on a
turbulent bed of limestone, sand, silica or aluminum. A typical RDF-fired combustor is shown in
Figure 4.3.1-4. Waste processing usually consists of removing noncombustibles and shredding,
which generally raises the heating value and provides a more uniform fuel. The type of RDF
used depends on the boiler design. Most boilers designed to burn RDF use spreader stokers and
fire fluff RDF in a semi-suspension mode.
Modular Combustors—Modular combustors are similar to mass burn combustors in that they burn
waste that has not been pre-processed, but they are typically shop fabricated and generally range
in size from 5 to 140 tons/day (4 to 130 Mg/day) of MSW throughput. One of the most common
types of modular combustors is the starved-air or controlled-air type, which incorporates two
combustion chambers. A process diagram of a typical modular starved-air (MOD/SA)
combustor is presented in Figure 4.3.1-5. Air is supplied to the primary chamber at
sub-stoichiometric levels. The incomplete combustion products (CO and organic compounds)
pass into the secondary combustion chamber, where additional air and fuel are added and
combustion is completed. Another type of design is the modular excess air (MOD/EA)
combustor that consists of two chambers, similar to MOD/SA units, but is functionally like the
mass burn unit in that it uses excess air in the primary chamber.
Emissions of PAH from municipal incinerators are suspected to occur primarily
from incomplete combustion of non-PAH carbonaceous material or high-temperature free radical
mechanisms (WHO, 1988). It is unlikely that PAHs in the refuse feed material persist
throughout the combustion process. It is estimated that PAHs account for less than 1 percent of
the total organic carbon (TOC) in the products of incineration.
4-129
-------
Superheater
Economizer
Auxiary Gas_Burners
-—-^
D
Steam Coo
Air Preheater
\
Source: U.S. EPA, 1993.
Figure 4.3.1-4. Typical RDF-Fired Spreader Stoker Boiler
-------
To Stack or
Waste Heat Boiler
Secondary
Chamber
Primary
Gas Burner
Fre Door Primary Chamber
Transfer Rams
Ram
Feeder
Charge
Hopper
Ash Quench
Primary Air
Secondary
Gas Burner
IO
O
o'
(E
Ul
Figure 4.3.1 -5. Typical Modular Starved-Air Combustor with Transfer Rams
Source: U.S. EPA, 1993.
-------
Failure to achieve complete combustion of the organic materials evolved from the
waste can result in emissions of a variety of organic compounds, including PAH. In general,
adequate oxygen, temperature, residence time, and turbulence will minimize emissions of most
organics. Tests show that advanced incinerators operating at sufficiently high temperatures and
with adequate oxygen, good mixing, and adequate retention time result in lower formation levels
of PAH than in traditional and poorly maintained or operated incinerators (WHO, 1988).
Emission Control Techniques-There are basically three methods to controlling emissions from
MWCs. These methods can be applied separately or in combination. The first method involves
separation of materials for recovery prior to combustion. The result of recovering certain
materials instead of combusting them is a reduction in the amount of waste combusted and in the
amount of pollutants emitted ("Federal Register. 1989).
Another method of controlling MWC emissions is to alter the combustion process
to reduce emissions of organics, including PAH. This method is referred to as Good Combustion
Practices (GCP). Good combustion practices include the proper design, construction, operation,
and maintenance of an MWC. The use of GCP reduces MWC organic emissions by promoting
more thorough combustion of these pollutants. Important elements of GCP include (Federal
Register. 1989).
• Maintaining uniform waste feed rates and conditions;
• The use of preheated air to combust wet or difficult to combust
materials;
• Maintaining adequate combustor temperature and residence time;
• Providing proper total combustion (excess) air levels;
• Supplying proper amounts of primary (underfire) and secondary
(overfire) air;
• Minimizing PM carryover;
• Monitoring the degree of waste burnout; and
4-132
-------
• The use of auxiliary fuel during startup and shutdown.
The third method of controlling MWC emissions is adding pollution control equipment after the
MWC. The most frequently used control devices for MWCs are combinations of spray dryers
and ESPs, or spray dryers and fabric filters (FF). Spray drying was initially developed to control
acid gas emissions. However, spray drying also controls MWC organic emissions, including
PAHs. Fabric filters and ESPs control paniculate matter emissions and, therefore, particle-
associated PAH (Federal Register. 1989).
Emission Factors
A search for MWC PAH emissions data produced information for the following
types of MWCs and control devices:
• Single chamber, reciprocating grate with ESP (Haile et al., 1984);
• Single chamber, fluidized bed, uncontrolled (Yasuda and Kaneko,
1989);
• Multiple chamber, rocking bar grate with wet scrubber and ESP
(Shih et al., 1980);
• Mass burn waterwall, reciprocating grate with ESP (MRI, 1987);
Multiple chamber with ESP (AmTest, Inc., 1989);
Multiple chamber, RDF with ESP (MRI, 1987);
Modular, starved-air, uncontrolled (U.S. EPA, 1989);
Modular, excess-air, with ESP (U.S. EPA, 1989);
• Mass burn waterwall with spray dryer and fabric filter (IWSA,
1996); and
• Mass burn waterwall with spray dryer and ESP (IWSA, 1996).
4-133
-------
The data obtained from the Integrated Waste Services Association (IWSA) was
used to develop PAH emission factors for MWCs because most of the MWC capacity in the
United States is at facilities of the types described in the data. Seventy percent of the MWC
capacity in the United States is at mass burn facilities (Bevington, et al., 1995). Also, the
majority of MSW is combusted at facilities subject to the MWC MACT, which requires that
spray dryers and ESPs or spray dryers and fabric filters be used as emission controls.
Evaluation of the IWSA data shows that naphthalene was the only PAH detected,
although the 16 PAHs were targeted. The other 15 PAHs were not detected in any sampling run
at any facility. Thus, naphthalene was the only PAH for which an emission factor was
developed. The factors for the facilities equipped with spray dryers and ESPs were not
significantly different in value from the factors for facilities equipped with spray dryers and
fabric filters. Therefore, the factors from both types of facilities were averaged together to obtain
the factor presented in Table 4.3.1-1.
Source Location
As of March 1995, there were roughly 130 MWC plants operating or under
construction in the United States with capacities greater than 40 tons/day (36 Mg/day), with a
total national capacity of approximately 103,300 tons/day (93,909 Mg/day) of MSW. Of the total
MWC capacity in the United States, 70 percent is at mass burn facilities, 25 percent is at RDF
facilities, 4 percent is a modular facilities, and the remaining 1 percent is at other technology
facilities such as co-fired RDF combustors. Ninety-one percent of the MWC facilities
(99 percent of MWC capacity) employ air emission controls of some kind (Bevington et al.,
1995). Table 4.3.1-2 lists the geographical distribution of these MWC units and their statewide
capacities (Bevington et al., 1995).
4-134
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TABLE 4.3.1-1. PAH EMISSION FACTORS FOR MUNICIPAL WASTE COMBUSTION SOURCES
sec
Number
5-01-001-05
Emission Source
Mass Burn, Water
Wall Combustor
Control Device Pollutant
Spray Dryer and Naphthalene
Fabric Filter, or Spray
Dryer and ESP
Average Emission
Factor in Ib/ton
(mg/Mg)a
6.06E-06
(3.04)
Emission Factor
Range in Ib/ion
(mg/Mg)a
4.81E-07- 1.46E-05
(2.40E-OI -7.29)
Emission
Factor
Rating
C
Reference
IWSA, 1996
"Emission factors are expressed in Ib (mg) of pollutant emitted per ton (Mg) of waste incinerated.
-------
TABLE 4.3.1-2. SUMMARY OF GEOGRAPHICAL DISTRIBUTION
OF MWC FACILITIES3
State
AK
AL
AR
CA
CT
FL
GA
HI
ID
IL
IN
MA
MD
ME
MI
Number of MWC
Facilities
2
1
4
3
7
14
1
1
1
1
1
11
4
4
7
State MWC Capacity in Percentage of Total MWC
tons/day Capacity in the United
(Mg/day) States
120 <1
(109)
690 <1
(627)
283 <1
(257)
2,560 2
(2,330)
6,545 6
(5,950)
18,248 17
(16,589)
500 <1
(450)
2,160 2
(1,964)
50 <1
(45)
1,600 1
(1,450)
2,360 2
(2,150)
11,003 10
(10,003)
5,910 5
(5,373)
2,000 2
(1,818)
5,225 5
(4,750)
4-136
(continued)
-------
TABLE 4.3.1-2. (Continued)
State
MN
MS
MT
NC
NH
NJ
NY
OH
OK
OR
PA
SC
TN
TX
UT
Number of MWC
Facilities
12
1
1
5
3
6
13
6
2
2
7
2
2
3
1
State MWC Capacity in Percentage of Total MWC
tons/day Capacity in the United
(Mg/day) States
5,102 5
(4,638)
150 <1
(140)
72 <1
(65)
1,324 1
(1,204)
832 1
(756)
5,820 6
(5,290)
11,545 11
(10,496)
1,800 2
(1,636)
1,230 1
(1,120)
675 1
(614)
8,702 8
(7,911)
870 1
(791)
1,250 1
(1,136)
195 <1
(177)
400 <1
(360)
4-137
(continued)
-------
TABLE 4.3.1-2. (Continued)
State MWC Capacity in Percentage of Total MWC
Number of MWC tons/day Capacity in the United
State Facilities (Mg/day) States
VA
WA
WI
6
5
4
6,325
(5,750)
1,500
(1,360)
831
(755)
6
1
1
"List of facilities represents the plants in operation or under construction/modification that are expected
to be subject to the MACT standards being developed for MWCs.
Source: Bevington et al., 1995.
4-138
-------
SECTION 4.3.1 REFERENCES
AMTest, Inc. U.S. Environmental Protection Agency Toxic Evaluation at Thermal Reduction
Company. Bellingham. Washington. Redmond, Washington, pp. 6,17. August 28, 1989.
Bevington, D. et al., Radian Corporation. "Municipal Waste Combustor Inventory Database."
Memorandum to Walt Stevenson, U.S. Environmental Protection Agency. May 17,1995.
Federal Register. December 20, 1989. Emission Guidelines: Municipal Waste Combustors.
Proposed Guidelines and Notice of Public Hearing. Volume 54, p. 52209.
Haile, C.L. et al. Assessment of Emissions of Specific Compounds from a Resource Recovery
Municipal Refuse Incinerator. U.S. Environmental Protection Agency, Office of Toxic
Substances, Washington, DC. EPA Report No. 560/5-84-002. June 1984.
Integrated Waste Services Association (IWSA), Written correspondence from Ms. Maria Zannes,
to Mr. Dennis Beauregard, U.S. Environmental Protection Agency. February 16, 1996.
Midwest Research Institute (MRI). Emission Data Base for Municipal Waste Combustors.
Prepared for U.S. Environmental Protection Agency, Emissions Standards and Engineering
Division, Research Triangle Park, North Carolina, p. 7-78. June 1987.
Shih, C. et al. "POM Emissions from Stationary Conventional Combustion Processes, with
Emphasis on Polychlorinated Compounds of Dibenzo-p-dioxin (PCDDs), Biphenyl (PCBs), and
Dibenzofuran (DCDFs)." CCEA Issue Paper presented under EPA Contract No. 68-02-3138.
U.S. Environmental Protection Agency, Industrial Environmental Research Laboratory, Research
Triangle Park, North Carolina. January 1980.
U.S. Environmental Protection Agency. Supplement F to Compilation of Air Pollutant Emission
Factors. Volume I: Stationary Point and Area Sources. Section 2.1. Office of Air Quality
Planning and Standards, Research Triangle Park, North Carolina. July 1993.
U.S. Environmental Protection Agency. Locating and Estimating Air Toxics Emissions From
Municipal Waste Combustors. Research Triangle Park, North Carolina. EPA-450/2-89-006
pp. 4-15 and 4-18. April 1989.
Yasuda, K., and M. Kaneko. "Basic Research on the Emission of Polycyclic Aromatic
Hydrocarbons Caused by Waste Incineration." Journal of the Air Pollution Control Association.
Volume 39, No. 12, pp. 1557-1561. 1989.
World Health Organization (WHO). Emissions of Heavy Metal and PAH compounds from.
Municipal Solid Waste Incinerators. Control Technology and Health Effects. WHO Regional
Office for Europe. Copenhagen, Denmark. 1988.
4-139
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4.3.2 Industrial and Commercial Waste Incineration
Process Description
In addition to municipal waste incinerators, some solid waste is also incinerated in
industrial and commercial facilities. Most individual waste incinerators at these sites are subject
to State and local air quality regulations such that these units have varying degrees of emissions
control. Most are equipped with afterburners, and newer units may have or be required to install
scrubbers or ESPs (Kelly, 1983).
Industrial wastes combusted in incinerators consist primarily of processing wastes
and plant refuse and contain paper, plastic, rubber, textiles, and wood. Because of the variety of
manufacturing operations, waste compositions are highly variable between plants, but may be
fairly consistent within a plant. Industrial waste incinerators are basically the same design as
municipal waste incinerators. Available data indicate that approximately 91 percent of the units
are multichamber designs, 8 percent are single chamber designs, and 1 percent are rotary kiln or
fluidized bed designs. About 1,500 of the estimated 3,800 industrial incinerators are used for
volume reduction, 640 units (largely in the petroleum and chemical industries) are used for
toxicity reduction, and the remaining 1,700 units are used for resource recovery, primarily at
copper wire and electric motor plants (Kelly, 1983).
Commercial waste incinerators are used to reduce the volume of wastes from
large office and living complexes, schools, and commercial facilities. Small multichamber
incinerators are typically used and over 90 percent of the units require firing of an auxiliary fuel.
Emission controls are generally not present on commercial units. The inefficient methods of
combustion used in the majority of commercial waste incinerators make these units potentially
significant POM emission sources (Kelly, 1983).
Polycyclic organic matter emissions from industrial and commercial waste
incineration are a function of waste composition, incinerator design and operating practices, and
incinerator emissions control equipment. Both the incineration of wastes and the combustion of
4-140
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incinerator auxiliary fuel may be sources of POM emissions. Greater organics and moisture
content in wastes increase potential POM emissions upon incineration. Incinerator design and
operating practices affect waste mixing, residence time in the flame zone, combustion
stoichiometry, and other factors that contribute to POM emissions generation. Incinerator
emission controls affect POM emissions by determining whether paniculate matter and gaseous
pollutants are controlled and to what extent. Generally, POM emissions exist in both paniculate
and gaseous forms, with available data indicating that often gaseous POM emissions
predominate. Incinerators with emission controls designed primarily for paniculate matter
collection may be accomplishing little POM emissions control.
Emission Factors
Available POM emission factor data for commercial waste incineration sources
are given in Table 4.3.2-1 (Hangebrauck et al., 1967). There were no available emission factors
for industrial waste incineration; however, to some extent this category is covered in
Section 4.1.2 of this report which includes the incineration of industrial wood waste.
The test data for commercial waste incinerators in Table 4.3.2-1 indicates that
POM emissions are generally greater from commercial sources than from municipal sources
(disregarding differences for controls). This apparent trend is probably attributable to
commercial units being operated and maintained less efficiently than municipal units, with
emphasis not being given to optimizing combustion conditions and waste destruction. In both of
the commercial unit tests described in the literature, pyrene and fluoranthene were consistently
the predominant POM compounds measured of those analyzed.
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TABLE 4.3.2-1. PAH EMISSION FACTORS FOR COMMERCIAL WASTE COMBUSTION SOURCES
SCC Number Emission Source Control Device Pollutant
5-02-001-02 Commercial Solid Waste Incinerator None Benzo(a)pyrene
- Single Chamber
Anthiacene
Benz< >(ghi)perylene
Fluoranthene
Phenanthrene
Pyrene
Benzo(e)pyrene
Perylene
Anthanthrene
Coronene
5-02-001-01 Commercial Solid Waste Incinerator None Benzo(a)pyrene
- Multiple Chamber
Anthiacene
Benzo(ghi)perylene
Fluoranthene
Average Emission Factor
in Ib/ton
(mg/Mg)11
2.34E-04
(117.00)
2.08E-04
(104.00)
3.97E-04
(198.00)
9.72E-04
(485.00)
6.19E-04
(309.00)
1.41E-03
(706.00)
1.99E-04
(99.20)
1.36E-05
(6.80)
2.93E-05
(14.60)
9.28E-05
(46.30)
1.15E-03
(573.00)
3.81E-04
(190.00)
3.84E-03
(1918.00)
1.72E-02
(8600.00)
Emission Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.3.2-1. (Continued)
SCC Number Emission Source
5-02-001-01 Commercial Solid Waste Incinerator
(continued) - Multiple Chamber
(continued)
Control Device Pollutant
None Phenanihrene
Pyrene
Benzo(e)pyrene
Perylene
Anthanthrene
Coronene
Average Emission Factor
in Ib/ton
(mg/Mg)a
2.61E04
(130.00)
1.86E-02
(9261.00)
1.15E-03
(573.00)
2.65E-04
(132.00)
3.49E-04
(174.00)
9.28E-04
(463.00)
Emission Factor
Rating
E
E
E
E
E
E
OJ
'Emission factors are expressed in Ib (mg) of pollutant emitted per ton (Mg) of waste incinerated.
Source: Hangebrauket al., 1967.
-------
Source Location
No site specific location information is available for commercial and industrial
waste incinerators. Commercial units are generally located in urbanized, metropolitan areas with
large concentrations of people. Locations of industrial waste incinerators parallel those of the
industries that use them for waste disposal. The lumber and wood products industries, the
primary metals industry, and the printing industry are the greatest users of incinerators for waste
disposal. Lumber and wood producers are primarily in the Southeast and Northwest. Primary
metals plants are predominantly in the Midwest, the Mideast, and the Southwest. The printing
industry has an essentially nationwide distribution (Kelly, 1983).
4-144
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SECTION 4.3.2 REFERENCES
Hangebrauck, R.P. et al. Sources of Polvnuclear Hydrocarbons in the Atmosphere.
U.S. Department of Health, Education, and Welfare, Public Health Service, Cincinnati, Ohio.
Public Health Service Report No. AP-33. pp. 14-18. 1967.
Kelly, M.E. Sources and Emissions of Polycyclic Organic Matter. U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina. EPA Report No. 450/5-83-010b.
pp. 5-75 to 5-82. 1983.
4-145
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4.3.3 Sewage Sludge Incineration
Process Description
The first step in the process of sewage sludge incineration is dewatering the
sludge. Sludge is generally dewatered until it is about 15 to 30 percent solids, at which point it
will burn without supplemental fuel. After dewatering, the sludge is sent to the incinerator for
combustion. The two main types of sewage sludge incinerators (SSIs) currently in use are the
multiple-hearth furnace (MHF) and the fluidized-bed combustor (FBC). Over 80 percent of the
identified operating sludge incinerators are MHFs and about 15 percent are FBCs. The
remaining combustors co-fire MSW with sludge (U.S. EPA, 1995).
Multiple Hearth Furnaces fMHFst-A cross-sectional diagram of a typical MHF is shown in
Figure 4.3.3-1. The basic MHF is a vertically oriented cylinder. The outer shell is constructed of
steel and lined with refractory material and surrounds a series of horizontal refractory hearths. A
hollow cast iron rotating shaft runs through the center of the hearths. Cooling air is introduced
into the shaft, which extends above the hearths. Attached to the central shaft are the rabble arms.
which extend above the hearths. Each rabble arm is equipped with a number of teeth,
approximately 6 inches in length and spaced about 10 inches apart. The teeth are shaped to rake
the sludge in a spiral motion, alternating in direction from the outside in to the inside out
between hearths. Burners, which provide auxiliary heat, are located in the sidewalls of the
hearths.
In most MHFs, partially dewatered sludge is fed onto the perimeter of the top
hearth. The rabble arms move the sludge through the incinerator by raking the sludge toward the
center shaft, where it drops through holes located at the center of the hearth. In the next hearth,
the sludge is raked in the opposite direction. This process is repeated in all of the subsequent
hearths. The effect of the rabble motion is to break up solid material to allow better surface
contact with heat and oxygen. A sludge depth of about 1 inch is maintained in each hearth at the
design sludge flow rate.
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Funoce EtfKxat
toAftebuner
Pyiotvsli
Product
Cooling and Comtx.-st!or Air
Feed Material
1,
S
Figure 4.3.3-1. Typical Multiple-Hearth Furnace
Source: U.S. EPA, 1995.
4-147
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Under normal operating conditions, 50 to 100 percent excess air must be added to
an MHF in order to ensure complete combustion of the sludge. Besides enhancing contact
between fuel and oxygen in the furnace, these relatively high rates of excess air are necessary to
compensate for normal variations in both the organic characteristics of the sludge feed and the
rate at which it enters the incinerator. When an inadequate amount of excess air is available,
only partial oxidation of the carbon will occur, with a resultant increase in emissions of CO, soot,
and hydrocarbons. Too much excess air, on the other hand, can cause increased entrainment of
paniculate and unnecessarily high auxiliary fuel consumption.
Fluidized-Bed Combustors—Figure 4.3.3-2 shows the cross-section diagram of an FBC.
Fluidized-bed combustors consist of a vertically oriented outer shell constructed of steel and
lined with refractory material. Tuyeres (nozzles designed to deliver blasts of air) are located at
the base of the furnace within a refractory-lined grid. A bed of sand, approximately 2.5 feet
(0.75 meters) thick, rests upon the grid. Two general configurations can be distinguished on the
basis of how the fluidizing air is injected into the furnace. In the hot windbox design, the
combustion air is first preheated by passing it through a heat exchanger, where heat is recovered
from the hot flue gases. Alternatively, ambient air can be injected directly into the furnace from
a cold windbox.
Partially dewatered sludge is fed into the lower portion of the furnace. Air
injected through the tuyeres at a pressure of 3 to 5 pounds per square inch grade (20 to
35 kilopascals) simultaneously fluidizes the bed of hot sand and the incoming sludge.
Temperatures of 1,400 to 1,700°F (750 to 925°C) are maintained in the bed. As the sludge
burns, fine ash particles are carried out the top of the furnace. Some sand is also removed in the
air stream and must be replaced at regular intervals.
Combustion of the sludge occurs in two zones. Within the sand bed itself (the
first zone), evaporation of the water and pyrolysis of the organic materials occur nearly
simultaneously as the temperature of the sludge is rapidly raised. In the freeboard area (the
second zone), the remaining free carbon and combustible gases are burned. The second zone
functions essentially as an afterburner.
4-148
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Exhaust and Ash
Thermocouple
Sludge
Inlet
Pressure Tap
Sight
Glass
Burner
Tuyeres
Fluidizing
Air Inlet
1
\
m
y
' Refractory N
Arch
J
., Windbox
m~
Fuel Gun
Pressure Tap
Startup
Preheat
Burner
for Hot
Windbox
Source: U.S. EPA, 1995.
Figure 4.3.3-2. Fluidized-Bed Combustor
4-149
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Fluidization achieves nearly ideal mixing between the sludge and the combustion
air, and the turbulence facilitates the transfer of heat from the hot sand to the sludge. The most
noticeable impact of the better burning atmosphere provided by an FBC is seen in the limited
amount of excess air required for complete combustion of the sludge. Typically, FBCs can
achieve complete combustion with 20 to 50 percent excess air, about half the excess air required
by MHFs. As a consequence, FBCs have generally lower fuel requirements compared to MHFs.
Emission Control Techniques— Many SSIs have greater variability in their organic emissions than
do other waste incinerators because, on average, sewage sludge has a high moisture content and
that moisture content can vary widely during operation. Failure to achieve complete combustion
of organic materials that evolve from the waste can result in emissions of a variety of organic
compounds, including POM. In general, adequate oxygen, temperature, residence time, and
turbulence will minimize emissions of most organics. The conditions of good combustion
practices (GCP) are summarized as follows: (U.S. EPA, 1995)
• Uniform wastefeed;
• Adequate supply and good air distribution in the incinerator;
• Sufficiently high incinerator gas temperatures (1 >500°F
Good mixing of combustion gas and air in all zones;
Minimization of PM entrainment into the flue gas leaving the
incinerator; and
Temperature control of the gas entering the APCD to 450 °F
(230°C) or less.
Additional reductions in POM emissions may be achieved by utilizing PM control
devices. The types of existing SSI PM controls range from low-pressure-drop spray towers and
wet cyclones to higher-pressure-drop venturi scrubbers and venturi/impingement tray scrubber
combinations. A few electrostatic precipitators and baghouses are employed, primarily where
sludge is co-fired with MSW. The most widely used PM control device applied to an MHF is the
4-150
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impingement tray scrubber. Older units use the tray scrubber alone; combination
venturi/impingement tray scrubbers are widely applied to newer MHFs and some FBCs.
Afterburners may be utilized to achieve additional reduction of organic emissions
in MHFs. Utilization of an afterburner provides a second opportunity for unburned hydrocarbons
to be fully combusted. In afterburning, furnace exhaust gases are ducted |p a chamber, where
they are mixed with supplemental fuel and air and completely combusted. Additionally, some
incinerators have the flexibility to allow sludge to be fed to a lower hearth, thus allowing the
upper hearth(s) to function essentially as an afterburner.
Emission Factors
The potential exists for many organic compounds to be emitted from SSIs because
of the wide variety of organic compounds in the sludge. Lower molecular weight, volatile PAH
compounds such as naphthalene may be emitted by volatilization of the compound. Higher
weight PAH compounds can result from incomplete combustion of the sludge.
Naphthalene is the most commonly reported PAH from emissions testing at SSIs.
One test study identified naphthalene as having one of the highest concentrations among
semi-volatile compounds in pre-control flue gas. Test data associated with other PAHs are
scarce, but the available data do show some PAH compounds besides naphthalene to be present
in small quantities.
Table 4.3.3-1 provides PAH emission factors for SSIs. The factors presented
cover the two main incinerator types: MHFs and FBCs. The factors for the MHF developed by
Johnson et al. (1990) come from testing conducted at three SSIs in Ontario, Canada, and one in
the United States. Naphthalene is by far the PAH compound emitted in the greatest quantity, and
the FBC units showed the highest naphthalene emission factor among the different incinerator
designs.
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TABLE 4.3.3-1. PAH EMISSION FACTORS FOR SEWAGE SLUDGE INCINERATORS
-f.
to
SCC Control
Number Emission Source Device Pollutant
5-01-005-15 Multi-Hearth Wet Scrubber Benz(a)anthracene
Furnace
Benzo(a)pyrene
Benzo(b)fluoranthe ne
Benzo(k)fluoranthene
Chrysene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenapthylene
Anthracene
Benzo(ghi)perylenc
Fluoranthene
Fluorene
Average Emission
Factor in Ib/ton
(mg/Mg)a
1.24E-06
(0.62)
1.02E-06
(0.51)
1.40E-07
(0.07)
1.22E-06
(0.61)
1.44E-05
(7.20)
2.00E-07
(0.10)
4.61E-07
(0.23)
8.02E-09
(4.00E-03)
1.60E-07
(0.08)
8.02E-08
(0.04)
1.24E-04
(62.00)
8.82E-06
(4.40)
Emission Factor Range
in Ib/ton (mg/Mg)a
3.61E-08 2.40E-06
(0.02- 1.2)
5.21E-07 - 2.00E-06
(0.26-1)
—
1.04E-06 1.40E-06
(0.52 - 0.7)
8.62E-06- 1.98E-05
(4.30 - 9.9)
4.81E-08 3.61E-07
(0.02 0.18)
4.41E-08 - 8.62E-07
(0.02 - 0.43)
3.41E-09- 1.38E-08
(0.00-0.0069)
2.81E-08-2.81E-07
(0.01 -0.14)
1.6E-08-1.24E-07
(0.01 - 0.062)
8.82E-06-3.81E-04
(4.40 - 190)
2.81E-06 1.80E-05
(1.40-9)
Emission
Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
Reference
Johnson et al,,
1990
Johnson et al.,
1990
Johnson et al.,
1990
Johnson et al.,
1990
Johnson et al.,
1990
Johnson et al.,
1990
Johnson et al.,
1990
Johnson, et al.,
1990
Johnson et al.,
1990
Johnson et al.,
1990
Johnson et al.,
1990
Johnson et al.,
1990
(continued)
-------
TABLE 4.3.3-1. (Continued)
SCC Control
Number Emission Source Device Pollutant
5-01-005-15 Multi-Hearth Wet Scrubber Naphthalene
(continued) Furnace (continued) (continued)
Phenanthrene
Pyrene
Benzo(a)fluorene
Benzo(e)pyrene
Coronene
Methylanthracenes
.{x
£t Methylphenanthrent s
u>
Perylene
5-01-005-15 Multi-Hearth Cyclone/ Naphthalene
Furnace Venturi
5-01-005-15 Multi-Hearth None Naphthalene
Furnace
5-01-005-15 Fluidi/ed-Bed Venturi/ Naphthalene
Combustor Impingement
Average Emission
Factor in Ib/ton
(mg/Mg)a
3.20E-03
(1,597)
8.82E-05
(44.00)
3.61E-06
(1.80)
1.76E-06
(0.88)
9.42E-07
(0.47)
8.02E-08
(0.04)
1.80E-07
(0.09)
7.82E-06
(3.90)
6.01E-08
(0.03)
1.94E-03
(970.00)
1.84E-02
(9,200.00)
1.94E-01
(97,000.00)
Emission Factor Range
in Ib/ton (ing/Mg)1
—
3.93E-05- 1.80E-04
(19.60 - 90)
3.21E-07 - 6.87E-06
(0.16-3.43)
6.21E-07-2.81E-06
(0.31 - 1.4)
4.41E-07- 1.44E-06
(0.22 - 0.72)
ND-1.48E-07
(ND - 0.074)
8.02E-09-3.41E-07
(0.00-0.17)
6.49E-05 - 9.02E-06
(32.40 - 4.5)
6.01E-09- 1.34E-07
(0.00 - 0.067)
;
—
...
Emission
Factor
Rating
E
E
E
E
E
E
E
E
E
D
E
E
Reference
Gerstle, 1988
Johnson et al.,
1990
Johnson et al.,
1990
Johnson et al.,
1990
Johnson et al.,
1990
Johnson et al.,
1990
Johnson et al.,
1990
Johnson et al.,
1990
Johnson et al.,
1990
U.S. EPA, 1995
U.S. EPA, 1995
U.S. EPA, 1995
'Emission factors are expressed in Ib (mg) pollutant emitted per ton (Mg) of dry sludge incinerated.
"--" means data not available.
-------
Source Location
There are approximately 170 sewage sludge incineration plants in operation in the
United States. Most sludge incinerators are located in the eastern United States, though there are
a significant number on the West Coast. New York has the largest number of facilities with 33.
Pennsylvania and Michigan have the next largest number of facilities with 21 and 19 sites,
respectively (U.S. EPA, 1990).
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SECTION 4.3.3 REFERENCES
Gerstle, R. W. "Emissions of Trace Metals and Organic Compounds from Sewage Sludge
Incineration." PEI Associates. Cincinnati, Ohio. For Presentation at the 81st Annual Meeting of
APCA, Dallas, Texas. June 19-24, 1988.
Johnson, N.D., M.T. Scholtz, V. Cassaday, and K. Davidson. MOE Toxic Chemical Emission
Inventory for Ontario and Eastern North America. Prepared for the Air Resources Branch,
Ontario Ministry of the Environment, Rexdale, Ontario. Draft Report No. P.89-50-5429/OG.
p. 173. March 15, 1990.
U.S. Environmental Protection Agency. Compilation of Air Pollutant Emissions Factors.
Volume I: Stationary Point and Area Sources. AP-42, Fifth Edition, Section 2.2: Sewage
Sludge Incineration. U.S. Environmental Protection Agency, Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. 1995.
U.S. Environmental Protection Agency. Locating and Estimating Air Toxics Emissions from
Sewage Sludge Incinerators. Office of Air Quality Standards, Research Triangle Park, North
Carolina. EPA-450/2-90-009. May 1990.
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4.3.4 Medical Waste Incineration
Medical waste incinerators (MWIs) burn wastes produced by hospitals, veterinary
facilities, crematories, and medical research facilities. These wastes include both infectious ("red
bag" and pathological) medical wastes and non-infectious general hospital wastes. The primary
purposes of MWIs are to (1) render the waste innocuous, (2) reduce the volume and mass of the
waste, and (3) provide waste-to-energy conversion. The total population of MWIs is estimated at
5,000, with the following distribution by facility category: 3,150 MWIs or 63 percent at
hospitals, 500 MWIs or 10 percent at laboratories, 550 MWIs or 11.6 percent at veterinary
facilities, 500 MWIs or 10 percent at nursing homes, and 300 MWIs at commercial and other
unidentified facilities (U.S. EPA, 1994).
Process Description
Three main types of incinerators are used as MWIs: controlled-air or starved-air,
excess-air, and rotary kiln. The majority (>95 percent) of incinerators are controlled-air units. A
small percentage (<2 percent) are excess-air, and less than 1 percent were identified as rotary
kiln. The rotary kiln units tend to be larger, and typically are equipped with air pollution control
devices. Approximately 2 percent of all the incinerators identified were equipped with air
pollution control devices (U.S. EPA, 1995).
Controlled-Air Incinerators-As noted above, controlled-air incineration is the most widely used
MWI technology, and now dominates the market for new systems at hospitals and similar
medical facilities. This technology is also known as two-stage incineration or modular
combustion. Figure 4.3.4-1 presents a schematic diagram of a typical controlled-air unit.
Combustion of waste in controlled-air incinerators occurs in two stages. In the
first stage, waste is fed into the primary, or lower, combustion chamber, which is operated with
less than the stoichiometric amount of air required for combustion. Combustion air enters the
primary chamber from beneath the incinerator hearth (below the burning bed of waste). This air
is called primary or underfire air. In the primary (starved-air) chamber, the low air-to-fuel ratio
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Carbon Dioxide,
— Watar Vapor
andExcaee
Oxygan and Nttrogan
to Atmoaphare
Air
Main Burner for
Minimum Combustion
Temperature
Volatile Content
is Burned in
Upper Chamber
Excess Air
Condition
Starved-Air
Condition in
Lower Chamber
Controlled
UnderfireAir
for Burning
Down Waste
Figure 4.3.4-1. Controlled-Air Incinerator
Source: U.S. EPA, 1995.
4-157
-------
dries and facilitates volatilization of the waste and most of the residual carbon in the ash burns.
At these conditions, combustion gas temperatures are relatively low (1,400 to 1,800°F [760 to
980°C]).
In the second stage, excess air is added to the volatile gases formed in the primary
chamber to complete combustion. Secondary chamber temperatures are higher than primary
chamber temperatures-typically 1,800 to 2,000°F (980 to 1,095°C). Depending on the heating
value and moisture content of the waste, additional heat may be needed. This can be provided by
auxiliary burners located at the entrance to the secondary (upper) chamber to maintain desired
temperatures.
Waste feed capacities for controlled-air incinerators range from about 75 to
6,500 Ib/hr (0.6 to 50 kg/min) (at an assumed fuel heating value of 8,500 Btu/lb [19,700 kJ/kg]).
Waste feed and ash removal can be manual or automatic, depending on the unit size and options
purchased. Throughput capacities for lower-heating-value wastes may be higher because feed
capacities are limited by primary chamber heat release rates. Heat release rates for controlled-air
incinerators typically range from about 15,000 to 25,000 Btu/hr-ft3 (430,000 to
710,000 Kj/hr-m3).
Excess-Air Incinerators--Excess-air incinerators are typically small modular units. They are also
referred to as batch incinerators, multiple-chamber incinerators, or "retort" incinerators.
Excess-air incinerators are typically a compact cube with a series of internal chambers and
baffles. Although they can be operated continuously, they are usually operated in a batch mode.
Figure 4.3.4-2 presents a schematic for an excess-air unit. Typically, waste is
manually fed into the combustion chamber. The charging door is then closed and an afterburner
is ignited to bring the secondary chamber to a target temperature (typically 1,600 to 1,800°F
[870 to 980°C]). When the target temperature is reached, the primary chamber burner ignites.
The waste is dried, ignited, and combusted by heat provided by the primary chamber burner, as
well as by radiant heat from the chamber walls. Moisture and volatile components in the waste
are vaporized and pass (along with combustion gases) out of the primary chamber and through a
4-158
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Flame Port
Stack
Charging
Door
Secondary
Air Ports
Igniti
Chamber
Mixing
Chamber
First
Underneath Port
Hearth
Secondary
Combustion
Chamber
Mixing
Chamber Flame Port
Side View
Cleanout
Doors
Charging Door
Hearth
Primary
Burner Port
Secondary
Underneath Port
CO
I
-------
flame port that connects the primary chamber to the secondary or mixing chamber. Secondary air
is added through the flame port and is mixed with the volatile components in the secondary
chamber. Burners are also installed in the secondary chamber to maintain adequate temperatures
for combustion of volatile gases. Gases exiting the secondary chamber are directed to the
incinerator stack or to an air pollution control device. After the chamber cools, ash is manually
removed from the primary chamber floor and a new charge of waste can be added.
Incinerators designed to burn general hospital waste operate at excess air levels of
up to 300 percent. If only pathological wastes are combusted, excess air levels near 100 percent
are more common. The lower excess air helps maintain higher chamber temperature when
burning high-moisture waste. Waste feed capacities for excess-air incinerators are usually
500 Ib/hr (3.8 kg/min) or less.
Rotary Kiln Incinerators-Rotary kiln incinerators, like the other types, are designed with a
primary chamber, where the waste is heated and volatilized, and a secondary chamber, where
combustion of the volatile fraction is completed. The primary chamber consists of a slightly
inclined, rotating kiln in which waste materials migrate from the feed end to the ash discharge
end. The waste throughput rate is controlled by adjusting the rate of kiln rotation and the angle
of inclination. Combustion air enters the primary chamber through a port. An auxiliary burner is
generally used to start combustion and maintain desired combustion temperatures.
Figure 4.3.4-3 presents a schematic diagram of a typical rotary kiln incinerator.
Volatiles and combustion gases pass from the primary chamber to the secondary chamber. The
secondary chamber operates at excess air. Combustion of the volatiles is completed in the
secondary chamber. Because of the turbulent motion of the waste in the primary chamber, solids
burnout rates and paniculate entrainment in the flue gas are higher for rotary kiln incinerators
than for other incinerator designs. As a result, rotary kiln incinerators generally have add-on
gas-cleaning devices.
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Exhaust Gas to Stack or
Air Pollution Control Device"
Waste Feed
-fx
•—*
O\
• Auxiliary Fuel
Ash Removal -
Figure 4.3.4-3. Rotary Kiln Incinerator
Source: U.S. EPA, 1995.
-------
Emission Control Techniques—Air emissions of organic compounds from MWIs
are controlled primarily by promoting complete combustion through the use of Good
Combustion Practice (GCP). As noted above, only a small percentage of MWIs use air pollution
control devices. The most frequently used devices are wet scrubbers and fabric filters. Fabric
filters mainly provide PM control. Other PM control technologies include venturi scrubbers and
electrostatic precipitators (ESPs). Generally, any of the PM control technologies will have a
beneficial effect in reducing particulate-phase PAH emissions as well.
Emissions of PAHs from MWIs are suspected to result primarily from incomplete
combustion. In general, GCP conditions such as adequate oxygen, temperature, residence time,
and turbulence will minimize emissions of most organics. There are little test data to support any
firm conclusions, but it is likely that advanced incinerators operating under GCPs will have lower
emissions of PAHs than poorly maintained or poorly operated incinerators. There are many
small MWIs that are not operating at maximum efficiency because of the minimal amount of
operator control over these units; these units would be expected to emit higher amounts of PAHs.
Emission Factors
The available PAH emission factors for MWIs are presented in Table 4.3.4-1.
Data for PAHs other than naphthalene were not available. It is expected that other PAHs are also
emitted as part of the combustion process and, as with MWCs, waste composition is a critical
factor in the amount of PAHs emitted.
The naphthalene factors developed by Walker and Cooper (1992), are based on
the operating test data from 17 MWIs. Data from 11 MWI facilities with emission controls and
6 MWI facilities without controls were analyzed. The facilities tested burned red bag waste,
pathological waste, and/or general hospital waste. For this study, red bag waste was defined as
any waste generated in the diagnosis or immunization of human beings or animals; pathological
waste was defined as any human and animal remains, tissues, and cultures; and general hospital
waste was defined as a mixture of red bag waste and municipal waste generated by the hospital.
4-162
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TABLE 4.3.4 1. PAH EMISSION FACTORS FOR MEDICAL WASTE INCINERATORS
SCC Number
5-01-005-05
5-01-005-05
Emission Source
Medical Waste
Incinerators,
Multi-Chamber and
Single-Chamber
Medical Waste
Incinerators,
Multi-Chamber and
Single-Chamber
Average Emission
Factor in Ib/ton
Control Device Pollutant (mg/Mg)a
None Naphthalene 1.62E-03
(808)
Scrubber/Baghouse Naphthalene 2.24E-04
(112)
Emission Factor Range
in Ib/ton
(mg/Mg)a
1.93E-04-1.26E-02
(96.4 - 6,300)
1.56E-04-2.95E-04
(77.8 - 147)
Emission Factor
Rating
C
C
'Emission factors are expressed as Ib (mg) of naphthalene emitted per ton (Mg) of medical waste incinerated.
Source: Walker and Cooper, 1992.
-------
Source Location
There are an estimated 5,000 MWIs in the United States, located at such facilities
as hospitals, pharmaceutical companies, research facilities, nursing homes, and other institutions
and companies that incinerate medical waste (U.S EPA, 1993).
4-164
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SECTION 4.3.4 REFERENCES
U.S. Environmental Protection Agency. Compilation of Air Pollutant Emission Factors.
Volume I: Stationary Point and Area Sources. AP-42, Fifth Edition, Section 2.3: Medical
Waste Incineration. Office of Air Quality Planning and Standards, Research Triangle Park,
North Carolina. 1995.
U.S. Environmental Protection Agency. Medical Waste Incinerators - Background Information
for Proposed Standards and Guidelines: Industry Profile Report for New and Existing Facilities.
Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina. EPA-
453/R-94-042a. July 1994.
U.S. Environmental Protection Agency. Locating and Estimating Air Toxic Emissions from
Sources of Medical Waste Incinerators. Office of Air Quality Planning and Standards, Research
Triangle Park, North Carolina. EPA-454/R-93-053. October 1993.
Walker, B. L., and C. D. Cooper. "Air Pollution Emission Factors for Medical Waste
Incinerators." Journal of the Air and Waste Management Association. Volume 4f2, No. 6,
pp. 784-791. 1992.
4-165
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4.3.5 Hazardous Waste Incineration
Hazardous waste, as defined by the Resource Conservation and Recovery Act
(RCRA) in 40 CFR Part 261, includes a wide variety of waste materials. Hazardous wastes are
produced in the form of liquids (e.g., waste oils, halogenated and nonhalogenated solvents, other
organic liquids, and pesticides/herbicides) and sludges and solids (e.g., halogenated and
nonhalogenated sludges and solids, dye and paint sludges, resins, and latex). Based on a 1986
study, total annual hazardous waste generation in the United States was approximately
292 million tons (265 million metric tons) (Oppelt, 1987). Only a small fraction of the waste
(<1 percent) was incinerated.
Based on an EPA study conducted in 1983, the major types of hazardous waste
streams incinerated were spent nonhalogenated solvents and corrosive and reactive wastes
contaminated with organics. Together, these accounted for 44 percent of the waste incinerated.
Other prominent wastes included hydrocyanic acid, acrylonitrile bottoms, and nonlisted ignitable
wastes.
Industrial kilns, boilers, and furnaces also burn hazardous wastes as fuel to
produce commercially viable products such as cement, lime, iron, asphalt, or steam. These
industrial sources require large inputs of fuel to produce the desired product. Hazardous waste,
which is considered an economical alternative to fossil fuels for energy and heat, is utilized as a
supplemental fuel. In the process of producing energy and heat, the hazardous wastes are
subjected to high temperatures for a sufficient time to destroy the hazardous content and the bulk
of the waste. The sections of this document describing Portland Cement Kilns, the Pulp and
Paper Industry, and Waste Oil Incineration include discussions of POM emissions from these
sources.
Process Description
Hazardous waste incineration is a process that employs thermal decomposition via
thermal oxidation at high temperatures (usually 1,650°F [900°C] or greater) to destroy the
4-166
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organic fraction of the waste and reduce volume. A diagram of the typical process component
options in a hazardous waste incineration facility is provided in Figure 4.3.5-1. The diagram
shows the major subsystems that may be incorporated into a hazardous waste incineration
system: (1) waste preparation and feeding, (2) combustion chamber(s), (3) air pollution control,
and (4) residue/ash handling.
Five types of hazardous waste incinerators are currently available and in
operation: liquid injection, rotary kiln, fixed-hearth, fluidized-bed, and fume injection (U.S.
EPA, 1986). Additionally, a few other technologies have been used for incineration of hazardous
waste, including ocean incineration vessels and mobile incinerators. These processes are not in
widespread use in the United States and are not discussed below.
Liquid Injection Incinerators—Liquid injection combustion chambers are applicable almost
exclusively for pumpable liquid waste, including some low-viscosity sludges and slurries. Liquid
injection units are usually simple, refractory-lined cylinders (either horizontally or vertically
aligned) equipped with one or more waste burners. The typical capacity of liquid injection units
is about 8 to 28 million Btu/hour (8.4 to 29.5 Gj/hour). Figure 4.3.5-2 presents a schematic
diagram of a typical liquid injection unit (U.S. EPA, 1986; Oppelt, 1987).
Rotary Kiln Incinerators—Rotary kiln incinerators are used in the destruction of solid wastes,
slurries, containerized waste, and liquids. Because of their versatility, these types of units are
most frequently used by commercial off-site incineration facilities. Rotary kiln incinerators
generally consist of two combustion chambers: a rotating kiln and an afterburner. The rotary
kiln is a cylindrical refractory-lined shell that is mounted on a slight incline. The primary
function of the kiln is to convert solid wastes to gases, which occurs through a series of
volatilization, destructive distillation, and partial combustion reactions. The typical capacity of
these units is about 10 to 60 million Btu/hour (10.5 to 63.3 Gj/hour). Figure 4.3.5-3 presents a
schematic diagram of a typical rotary kiln unit.
4-167
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Waste Preparation
\
Blending
Screening
Shredding
Heating
Atomization
Ram
Gravity
Auger
Lance
Combustion
Liquid Injection
Rotary Kiln
Fixed Hearth
Fluidized Bed
Air Pollution Control
_L
Quench
Heat
Recovery
Venturi
Wet ESP*
IWS*
Fabric Filter
Packed Tower
SprayTower
Tray Tower
IWS
Wet ESP
Waste
Preparation
^
w
Waste
Feeding
Combustion
Chamber(s)
IWS = Ionizing Wet Scrubber
ESP = Electrostatic Precipitate*
POTW = PubUcally Owned
Treatment Works
Combustion
Gas
Conditioning
Ash
Disposal
Particulate
Removal
Dewatering
Chemical
Stabilization
Secure Landfill
i
Residue
Treatment
Acid
Gas
Remova
-,
^
W
Demlster
and
Stack
Return to
Process
POTW*
Neutralization
Chemical Treatment
Residue
and Ash
Handling
Figure 4.3.5-1. Typical Process Component Options in a Hazardous Waste Incineration Facility
Source: Oppelt, 1987.
-------
o\
VO
Aqueous
Waste
Steam
Auxiliary
Fuel
Liquid
Waste
Atomizing
Steam or
Air
Air
120-250%
Excess Air \
-Refractory Wall
T/TT/Tr/TTTT/T/,
Primary
Combustion
Air
Discharge
to Quench or
Waste Heat Recovery
zzzzffk
7,
0.3 - 2.0 Seconds
Mean Combustion
Gas Residence Time
1500
-------
Combustion
Air
Waste Liquids
Auxiliary Fuel
Waste solids^
Containers or
Sludges
Kiln
Shroud
Discharge to
Quench or
Heat Recovery
50-250%
Excess Air
1.O-3.0 Seconds
MeanOaa
Residence Time
Refractory
Ash
Rotary Kiln
Afterburner
Figure 4.3.5-3. Typical Rotary Kiln/Afterburner Combustion Chamber
ERO_Pa_»!7.a«4
Source: Oppelt, 1987.
-------
An afterburner is connected directly to the discharge end of the kiln. The
afterburner is used to ensure complete combustion of flue gases before their treatment for air
pollutants. A tertiary combustion chamber may be added if needed. The afterburner itself may
be horizontally or vertically aligned, and functions on much the same principles as the liquid
injection unit described above. Both the afterburner and the kiln are usually equipped with an
auxiliary fuel-firing system to control the operating temperature.
Fixed-hearth Incinerators— Figure 4.3.5-4 presents a schematic diagram of a typical fixed-hearth
unit (U.S EPA, 1986; Oppelt, 1987). Fixed-hearth incinerators, also called controlled-air,
starved-air, or pyrolytic incinerators, are the third major technology used for hazardous waste
incineration (Oppelt, 1987). This type of incinerator may be used for the destruction of solid,
sludge, and liquid wastes. Fixed-hearth units tend to be of smaller capacity (typically 5 million
Btu/hour [5.3 Gj/hour]) than liquid injection or rotary kiln incinerators because of physical
limitations in ram feeding and transporting large amounts of waste materials through the
combustion chamber.
u-heaith units consist of a two-stage combustion process, similar to that of
rotary kilns. Waste is ram fed into the primary chamber and burned at about 50 to 80 percent of
stoichiometric air requirements. This starved-air condition causes most of the volatile fraction to
be destroyed pyrolitically. The resultant smoke and pyrolytic products pass to the secondary
chamber, where additional air and, in some cases, supplemental fuel, is injected to complete the
combustion (Oppelt, 1987).
Fluidized-bed Incinerators— Fluidized-bed incinerators, described in Section 4.3.3 of this report,
have only recently been applied to hazardous waste incineration. FBCs used to dispose of
hazardous waste are very similar to those used to incinerate sewage sludge except for their
additional capability of handling liquid wastes.
FBCs are suitable for disposing of combustible solids, liquids, and gaseous
wastes. They are not suited for irregular, bulky wastes, tarry solids, or other wastes that leave
residues in the bed (Whitworth, 1992). Fluidized bed combustion chambers consist of a single
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Auxiliary Fuel
Discharge to
Quench or
Heat Recovery
0.25-2.5 Seconds
Mean Residence Time
Secondary
Chamber
1400'F-2000'F
Ram
Figure 4.3.5-4. Typical Fixed-Hearth Combustion Chamber
Steam
Auxiliary Fuel or
Liquid Waste
Refractory
Source: Oppelt, 1987.
-------
refractory-lined combustion vessel partially filled with inert granular material (e.g., particles of
sand, alumina, and sodium carbonate) (Oppelt, 1987). The typical capacity of this type of
incinerator is 45 million Btu/hour (47.5 Gj/hour).
Fume Injection Incinerators-Fume injection incinerators are used exclusively to destroy gaseous
or fume wastes. The combustion chamber is comparable to that of a liquid-injection incinerator
(Figure 4.3.5-2) in that it usually has a single chamber, is vertically or horizontally aligned, and
uses nozzles to inject the waste into the chamber for combustion. Waste gases are injected by
pressure or atomization through the burner nozzles. Wastes may be combusted solely by thermal
or catalytic oxidation.
Emission Control Techniques—Most organics control for hazardous waste incinerators is
achieved by promoting complete combustion through GCP. The conditions of GCP are
summarized in Section 4.3.3, Sewage Sludge Incineration. Failure to achieve complete
combustion of organic materials evolved from the waste can result in emissions of a variety of
organic compounds, including POM. In general, adequate oxygen, temperature, residence time,
?nd turbulence will minimize emissions of most organics.
Additionally, control of organics, including POM, may be partially achieved by
using PM control devices. The most frequently used control devices for PM control are wet
scrubbers and fabric filters. Other PM control technologies include venturi scrubbers and
electrostatic precipitators (ESPs).
Emission Factors
Few test data are available on POM emissions from hazardous waste incinerators.
The available data have primarily included only naphthalene emissions measurements. However,
it is expected that, as with other combustion sources, other PAH compounds are emitted as a
result of incomplete combustion and possibly from the fuel itself. The composition of the fuel,
or waste in this case, varies tremendously in the hazardous waste incineration industry, more so
than with most of the other combustion sources discussed in this document. In many cases, the
4-173
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fuel represents a combination of many different wastes and, depending on the content, may or
may not result in significant POM emissions.
PAH emission factors for hazardous waste incineration are provided in
Table 4.3.5-1. These factors represent the incineration of various types of hazardous wastes in
different combustion configurations. Because of the impact of waste composition on PAH
emissions, these factors should be used only as a relative measure of PAH emissions from
hazardous waste incinerators. The characterization of each of the individual waste types that
were incinerated at the facilities on which these factors are based were not available; therefore, it
is impossible to assume that these factors are applicable to any given hazardous waste incinerator
scenario. It should be noted, however, that naphthalene can be one of the more important PAHs
emitted from this source in terms of quantity of emissions. Another test study of various
hazardous waste incinerators, including liquid injection, rotary kiln and hearth configurations,
reported concentrations of naphthalene in the exhaust gas that were 100 times greater than the
two other reported compounds, pyrene and fluoranthene (Trenholm et al., 1984). The high
concentrations reported for naphthalene relative to other PAHs is consistent with other waste
combustion source categories covered earlier in this document.
Source Location
Approximately 221 hazardous waste incinerators are operating under the Resource
Conservation and Recovery Act (RCRA) system in the United States. These incinerators are
located at 189 separate facilities, 171 of which are located at the site of waste generation (Oppelt,
1987). Texas has the most incinerators with 27 facilities, followed by Louisiana and Ohio, each
with 17 facilities, and California with 15 facilities. Some of the smaller incinerators and those
that are designed to be mobile are not permanent facilities, but are set up at the site where the
waste is being removed. Other facilities are permanent and accept waste from different sites
across the country.
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TABLE 4.3.5-1. PAH EMISSION FACTORS FOR HAZARDOUS WASTE INCINERATORS
SCC Control
Number Emission Source Device Pollutant
5-03-005-01 Liquid Injection Scrubber/ Benz(a)anthracene
Incinerator for Baghouse
Mixed Liquid
Industrial Waste,
Dual-Chamber Design
Benzo(a)pyrene
Bcnzofluoranthenes
Chrysene/Triphenylene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)py i ene
Acenaphthene
Benzo(ghi)perylenc
Anthracene
Fluoranthene
Fluorene
Phenanthrene
Average Emission Factor in Emission
Ib/ton Factor
(mg/Mg)a Rating Reference
6.01E-06
(3.00)
2.00E-06
(1.00)
5.01 E-06
(2.50)
1.10E-05
(5.50)
1.20E-06
(0.60)
3.81 E-06
(1.90)
7.21 E-06
(3.60)
4.21 E-06
(2 10)
1.16E-05
(5.80)
4.97E-05
(24.80)
1.34E-05
(6.70)
1.01E-04
(50 20)
E Johnson et al., 1990
E Johnson et al., 1990
E Johnson et al., 1990
E Johnson etal., 1990
E Johnson et al., 1990
E Johnson et al., 1990
E Johnson et al., 1990
E Johnson et al., 1990
E Johnson et al., 1990
E Johnson et al., 1990
E Johnson et al., 1990
E Johnson et al., 1990
(continued)
-------
TABLE 4.3.5-1. (Continued)
sec
Number Emission Source
5-03-005-01 Liquid Injection
(continued) Incinerator for
Mixed Liquid
Industrial Waste,
Dual-Chamber Design
(continued)
£
ON
5-03-005-01 Hazardous Waste
Incinerator
5-03-005-01 Industrial
Boiler Burning
Hazardous Waste
Control
Device Pollutant
Scrubber/ Pyrene
Baghouse
(continued)
Benzo(e)pyrene
Coronene
Methylanthracenes
Methylphenanthrenes
Perylene
Acenapthalene
Unknown Naphthalene
Unknown Naphthalene
Average Emission Factor in
Ib/ton
(mg/Mg)a
2.81E-05
(14.00)
2.00E-06
(1.00)
2.61E-06
(1.30)
3.79E-05
(18.90)
1.76E-05
(8.80)
6.01E-07
(0.30)
5.41E-06
(2.70)
102.586 Ib/MMBtu
(44.00 ng/kJ)
1.3989 Ib/MMBtu
(0.60 ng/kJ)
Emission
Factor
Rating Reference
E Johnson etal., 1990
E Johnson et al., 1990
E Johnson et al., 1990
E Johnson et al., 1990
E Johnson et al., 1990
E Johnson et al., 1990
E Johnson et al., 1990
E Oppelt, 1987
E Oppelt, 1987
"Emission factors are expressed as Ib (mg) of pollutant per ton (Mg) of waste incinerated, except where otherwise indicated.
-------
SECTION 4.3.5 REFERENCES
Johnson, N.D., M.T. Scholtz, V. Cassaday, and K. Davidson. MOE Toxic Chemical Emission
Inventory for Ontario and Eastern North America. Prepared for the Air Resources Branch,
Ontario Ministry of the Environment, Rexdale, Ontario. Draft Report No. P.89-50-5429/OG.
p. 151. 1990.
Oppelt, E.T. "Incineration of Hazardous Waste - A Critical Review." Journal of Air Pollution
Control Association. Volume 37, Number 5, pp. 558-586. 1987.
Trenholm, A., P. Gorman, B. Smith, and D.A. Oberacker. Emission Test Results for a
Hazardous Waste Incineration RIA. U.S. Environmental Protection Agency. EPA-600/9-84-015.
1984.
U.S. Environmental Protection Agency. Permit Writer's Guide to Test Bum Data - Hazardous
Waste Incineration. Office of Research and Development, Washington, DC.
EPA-625/6-86-012. 1986.
Whitworth, W.E., L.E. Waterland. Pilot-Scale Incineration of PCB-Contaminated Sediments
from the Hot Spot of the New Bedford Harbor Superfund Site. Acurex Corporation. Jefferson,
Arkansas. 1992.
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4.3.6 Drum and Barrel Reclamation
Process Description
POM emissions have been detected in the stack gases from drum reclamation
facilities. These facilities typically consist of a furnace that is used to heat the drums to an
elevated temperature in order to destroy any residual materials in the containers. The drums are
then repaired, repainted, relined, and sold for reuse.
The drums processed at these facilities come from a variety of sources, such as the
petroleum and chemical industries, and sometimes contain residual waste that is classified as
hazardous according to the EPA's Resource Conservation and Recovery Act (RCRA) guidelines.
The furnaces are fired by an auxiliary fuel such as oil or natural gas. The used
drums are typically loaded onto a conveyor, which carries them through the heat treatment zone.
As the drums proceed through this process, any residual contents, paint, and interior linings are
burned off or disintegrated. POM formation can occur from either the heat treatment of the
barrels or from the combustion of the auxiliary fuel.
Emission Factors
Only one test report (Galson Corporation, 1992) was found that measured
emissions of specific PAH compounds from a drum reclamation facility. The facility tested
recycles 55-gallon drums. There was no indication as to the physical or chemical characteristics
of the residual waste in the drums, or of the auxiliary fuel type used to fire the furnace. The drum
furnace consists of a boiler with a 10,200 Btu/hr capacity in conjunction with a 8,256,000 Btu/hr
boiler and an afterburner that serves as an emissions control device. Table 4.3.6-1 shows PAH
emission factors developed for this facility.
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TABLE 4.3.6-1. PAH EMISSION FACTORS FOR DRUM AND BARREL RECLAMATION
SCC Number Emission Source Control Device Pollutant
5-03-005-01 55-gallon Drum Afterburner Benz(a (anthracene
Recycling Furnace
Benzol b)fluoi anthene
Chrysene
Acenaphthene
Acenapthylene
Anthracene
Fluoranthene
Fluoreneb
Naphthaleneb
Phenanthreneb
Pyrene
Average Emission Factor
in lb/ 1 000 barrels
(mg/1000 barrels)11
3.54E-07
(0.16)
1.33E-07
(0.06)
6.63E-08
(0.03)
2.85E-06
(1.29)
7.07E-07
(0.32)
2.63E-06
(1.19)
5.30E-07
(0.24)
6.32E-06
(2.86)
1.67E-05
(7.54)
4.66E-06
(2.11)
6.63E-07
(0.3)
Emission Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
"Emission factors are expressed in lb (mg) of pollutant emitted per thousand 55-gallon barrels processed.
bCompound also detected in field blank; emission rate not adjusted for field blank detection
Source: Qalson Corporation, 1992.
-------
The emission factors for drum reclamation should be used cautiously because the
nature of the residual waste product can vary greatly from facility to facility, which will likely
affect PAH emissions. The type of auxiliary fuel used can also have a significant effect on PAH
emissions from these facilities.
Source Location
Approximately 2.8 to 6.4 million 55-gallon drums are incinerated annually in the
U.S. (U.S. EPA, 1994). This estimate is based on the assumptions that there are 23 to
26 incinerators currently in operation, each incinerator handles 500 to 1,000 drums per day, and
each incinerator operates 5 days a week with 14 days down time for maintenance.
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SECTION 4.3.6 REFERENCES
Gal son Corporation. Source Emission Test Results for Drum Furnace/Afterburner. Galson
Technical Services, Berkeley, California. Galson Project #SE-280. 1992.
U.S. Environmental Protection Agency. Estimating Exposures to Dioxin-Like Compounds.
Volume II: Properties. Sources. Occurrence, and Background Exposures. External Review
Draft. EPA-600/6-88-005Cb. Office of Health and Environmental Assessment, Washington,
DC. 1994.
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4.3.7 Scrap Tire Incineration
Most facilities that burn tires use the tires to supplement a primary fuel, such as
wood. This section, however, addresses those facilities that burn scrap tires as the only fuel. The
primary purpose of these facilities is to recover energy from the combustion of scrap tires.
Process Description
The following process description is based on the operations at the Modesto
Energy Facility in Westley, California, which is a dedicated tire-to-energy facility. This process
should be applicable to most of these types of facilities because the technology is licensed to one
company in the United States.
The Modesto facility consists of two whole-tire boilers that generate steam from
the combustion of the scrap tires. Tires from a nearby supply pile are fed into a hopper located
adjacent to the pile. Tires are then fed into the boilers at a rate of 350 to 400 tires per hour for
each boiler. The boilers can accommodate tires as large as 4 feet in diameter made of rubber.
fiberglass, polyester, and nylon.
The tires are burned on large reciprocating stoker grates in the combustion
chamber at the bottom of the boilers. The grate configuration allows air flow above and below
the tires, which aids in complete combustion. The boilers are operated above 2,000°F (1,093°C)
to ensure complete combustion of organic compounds emitted by the burning tires. The heat
generated by the burning of the tires causes the water contained in the pipes of the refractory
brickwork that lines the boiler to turn into steam. The high-pressure steam is then forced through
a turbine for the generation of power.
Three air pollution control techniques are used at the Modesto facility to control
NOX, PM, and SOr The PM control device, a fabric filter, likely has the most significant impact
on paniculate POM emissions. After exiting the boiler chamber and the NOX control system,
exhaust gases pass through the large fabric filter.
4-182
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Emission Factors
PAHs have been measured in the post-control exhaust gas at the Modesto facility.
Emission factors developed from these data are provided in Table 4.3.7-1. These factors were
generated assuming a heating value of 300,000 Btu per tire. Emission data from other
tire-to-energy facilities were not available; however, facilities that use similar technology would
be expected to have PAH emissions in the same of order of magnitude as the Modesto facility.
Source Location
The EPA's Office of Solid Waste has estimated that approximately 25.9 million
scrap tires were incinerated in the United States in 1990 (U.S. EPA, 1992). This equates to
approximately 10.7 percent of the 242 million scrap tires that were generated in 1990. The use of
scrap tires as fuel increased significantly during the late 1980s, and is expected to continue to
increase (U.S. EPA, 1992).
In December 1991, there wue Uvo operational, dedicated tire-to-energ> facilities
in the United States: the Modesto Energy Project in Westley, California, and the Exter Energy
Company in Sterling, Connecticut. The Erie Energy Project, which was still in the planning
stages when this document was written, was to be located at Lackawanna, New York. The total
capacity for all three plants combined could approach almost 25 million tires per year
(4.5 million at the Modesto plant, and 10 million each at the Exter and Erie plants) (U.S. EPA,
1991).
4-183
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TABLE 4.3.7-1. PAH EMISSION FACTORS FOR SCRAP TIRE BURNING
SCC Number Emission Source Control Device Pollutant
5-03-001-02 Scrap Tire Incinerator Fabric Filter Benzo(b)fluoranthene
Acenaphthene
Anthracene
Fluoranthene
Fluorene
JX Naphthalene
oo
Phenanthrene
Pyrene
Average Emission Factor
in Ib/million tires
(g/million tires)3
I.68E-03
(0.76)
1.68E-03
(0.76)
3.00E-03
(1.36)
5.10E-03
(2.31)
5.10E-03
(2.31)
3.60E-01
(163.30)
1.68E-02
(7.62)
6.60E-03
(2.99)
Emission Factor
Rating
E
E
E
E
E
E
E
E
"Emission factors are expressed in Ib (g) of pollutant emitted per million scrap tires incinerated.
Source: U.S. EPA, 1991.
-------
SECTION 4.3.7 REFERENCES
U.S. Environmental Protection Agency. Summary of Markets for Scrap Tires. Office of Solid
Waste, Washington, DC. EPA/530-SW-90-074B. 1992.
U.S. Environmental Protection Agency. Burning Tires for Fuel and Tire Pyrolysis: Air
Implications. Office of Air Quality Planning and Standards, Research Triangle Park, North
Carolina. EPA-450/3-91-024. pp. 3-1 to 3-21. 1991.
4-185
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4.3.8 Landfill Waste Gas Flares
Process Description
A municipal solid waste (MSW) landfill unit is a discrete area of land or an
excavation that receives household waste. An MSW landfill unit may also receive other types of
wastes, such as commercial solid waste, nonhazardous sludge, and industrial solid waste
(U.S. EPA, 1995). POM emissions from MSW landfills are expected to originate from the
flaring of waste gas that evolves from the landfill. Waste gas evolves from the biodegradation
process, vaporization, and chemical reactions at the landfill, and at some sites it is collected
through a piping network and then burned at the top of vent pipes.
Landfill gas collection systems are either active or passive systems. Active
collection systems provide a pressure gradient in order to extract landfill gas by use of
mechanical blowers or compressors. Passive systems allow the natural pressure gradient created
by the increase in landfill pressure from landfill gas generation to mobilize the gas for collection.
Landfill gas control and treatment options include (1) combustion of the landfill
gas, and (2) purification of the landfill gas. Combustion practices producing POM emissions
include techniques that do not recover energy (e.g., flares and thermal incinerators) and
techniques that do recover energy and generate electricity from the combustion of the landfill gas
(e.g., gas turbines and internal combustion engines). Boilers can also be employed to recover
energy from landfill gas in the form of steam (U.S. EPA, 1995). The formation of POM from
boilers, internal combustion engines and turbines are discussed in Sections 4.1.2, 4.2.1, and
4.2.2, respectively, of this report.
Flares involve an open combustion process that requires oxygen for combustion;
the flares themselves can be open or enclosed. Thermal incinerators heat an organic chemical to
a high enough temperature in the presence of sufficient oxygen to oxidize the chemical to CO2
and water. Purification techniques can also be used to process raw landfill gas to pipeline quality
natural gas by using adsorption, absorption, and membranes (U.S. EPA, 1994).
4-186
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Emission Factors
PAH emission factors for a landfill flare are presented in Table 4.3.8-1. The
factors are based on a test conducted for a burner rated at 31 MMBtu/hr (Gj/hr). Combustion air
is drawn into the base of the flare through dampered openings. Landfill gas is fed to the burner
just above the dampered openings and combustion takes place inside the refractory lined flare.
Test samples were taken from the flare exhaust. Emission factors were derived from the test
samples based on the heat input of the waste gas (U.S. EPA, 1994).
Naphthalene, acenaphthene, fluorene, pyrene, chrysene, benzo(b)fluoranthene,
benzo(e)pyrene, indeno(l,2,3-cd)pyrene and benzo(ghi)perylene were all found in the test
sample, but not in significant quantities when compared to the blank. Measurable quantities of
phenanthrene and fluoranthene were present above the blank values. Acenaphthalene,
anthracene, benzo(a)anthracene, benzo(k)fluoranthene, benzo(a)pyrene, perylene, and
dibenz(a.h)anthracene were found in the test sample at the detection limit.
Source Location
MSW management in the United States is dominated by disposal in landfills.
Approximately 67 percent of solid waste is landfilled, 16 percent is incinerated, and 17 percent is
recycled or composted. There were an estimated 5,345 active MSW landfills in the United States
in 1992. In 1990, active landfills were receiving an estimated 130 million tons (118 million Mg)
of waste annually, with 55 to 60 percent reported as household waste and 35 to 45 percent
reported as commercial waste (U.S. EPA, 1995).
4-187
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TABLE 4.3.8-1. PAH EMISSION FACTORS FOR LANDFILL FLARES
oo
oo
SCC Number Emission Source Control Device Pollutant
5-02-006-01 Solid Waste Landfill (Waste Afterburner Ben/(a)anthracene
Gas Flares) „ , ,
Ben/.o(a)pyrene
B en / o(k)fluo ranthene
Chrysene
Dibcnz(a,h)anthracene
Indeno(l,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Ben/o(ghi)perylene
Anthracene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrcne
Average Emission
Factor (lb/MMBtu)a
6.26E-11
1.14E-10
6.49E-11
2.97E-08
2.77E-10
5.83E-10
1.05E-07
4.27E-08
9.53E-10
2.32E-10
7.26E-07
1.50E-07
l.OOE-05
1.88E-06
1.56E-08
Average
Emission
Factor (g/kj)a
2.69E-14
4.89E-14
2.78E-14
1.27E-11
1.19E-13
2.50E-13
4.50E-11
1.83E-11
4.09E-13
9.95E-14
3.11E-10
6.44E-11
4.29E-09
8.07E-10
6.69E-12
Emission Factor
Rating
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
"Emission factors are expressed in Ib (g) of pollutant emitted per MMBtu (kj) of heat input into the burner.
Source: U.S. EPA, 1994.
-------
SECTION 4.3.8 REFERENCES
U.S. Environmental Protection Agency. Compilation of Air Pollutant Emissions Factors.
Volume I: Stationary Point and Area Sources. AP-42, Fifth Edition, Section 2.4: Landfills.
U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Research
Triangle Park, North Carolina. 1995.
U.S. Environmental Protection Agency. Factor Information Retrieval (FIRE) System Database,
"Compliance Testing for Non-Criteria Pollutants at a Landfill Flare. November 1990.
(Confidential Report No. ERC-2)." Record Reference 1097, Version 2.62. 1994.
4-189
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4.4 METAL INDUSTRY
4.4.1 Primary Aluminum Production
Process Description
All primary aluminum in the United States is produced by the Hall-Heroult
process of electrolytic reduction of alumina. The general procedures for primary aluminum
reduction are illustrated in Figure 4.4.1-1 (U.S. EPA, 1979). Aluminum reduction is carried out
in shallow rectangular cells (pots) made of carbon-lined steel, with carbon blocks suspended
above and extending down into the pot. The pots and carbon blocks serve as cathodes and
anodes, respectively, for the electrolytical process (U.S. EPA, 1979; Siebert et al., 1978;
Wallingford and Hee, 1985).
Cryolite (Na3AlF6), a double fluoride salt of sodium and aluminum, serves as an
electrolyte and a solvent for alumina. Alumina is added to and dissolves in the molten cryolite
bath The cells are heated and operated between 1,742 to 1,832°F (950 to 1,000°C) with heat
that results from resistance between the electrodes. During the reduction process, the aluminum
is deposited at the cathode where, because of its heavier weight (2.3 g/cm3 versus 2.1 g/cm3 for
cryolite), it remains as a molten metal layer underneath the cryolite. The cryolite bath thus also
protects the aluminum from the atmosphere. The byproduct oxygen migrates to and combines
with the consumable carbon anode to form CO2 and CO, which continually evolve from the cell.
The basic reaction of the reduction process is (U.S. EPA, 1979):
A1203 + 1.5C —> 2A1 + 1.5CO2
Alumina and cryolite are periodically added to the bath to replenish material that
is removed or consumed in normal operation. The weight ratio of sodium fluoride (NaF) to
aluminum fluoride (A1F3) in cryolite is 1.5. Fluorspar (calcium fluoride) may also be added to
lower the bath's melting point. Periodically, the molten aluminum is siphoned or tapped from
beneath the cryolite bath, moved in the molten state to holding furnaces in the casting area, and
4-190
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1
fl
1
1
MU.
MU.
VIMATMO
teuton
•0
POM
EMISSIONS
POM
EMISSIONS
WfDID KM MOMfO
ntOCIMOMLY
Figure 4.4.1 -1. General Flow Diagram for Primary Aluminum Reduction
Source: U.S. EPA, 1979.
4-191
-------
fluxed to remove trace impurities. The product aluminum is later tapped from the holding
furnaces and cast into ingots or billets to await further processing or it is shipped as molten in
insulated ladles (U.S. EPA, 1979).
The process of primary aluminum reduction is essentially one of materials
handling. The true difference in the various process modifications used by the industry lies in the
type of reduction cell used. Three types of reduction cells or pots are used in the United States:
prebake, horizontal stud Soderberg, and vertical stud Soderberg (Figure 4.4.1-2). Prebake cells
constitute the bulk of aluminum production (66 percent), followed by horizontal Soderbergs
(21 percent), and vertical Soderbergs (13 percent) (U.S. EPA, 1979). Both Soderberg cells
employ continuously formed consumable carbon anodes, where the anode paste is baked by the
energy of the reduction cell itself. The prebake cell, as indicated by its name, employs a
replaceable, consumable carbon anode, formed by baking in a separate facility called an anode
bake plant, prior to its use in the cell.
The preparation and operation of the aluminum reduction cells is the primary
source of potential POM emissions from primary aluminum production. The magnitude of POM
emissions from a typical reduction plant is a function of the type of reduction cell used
(Siebert et al., 1978). Prebaked cell anodes are made by curing the carbon contained in pitch and
coke at relatively high temperatures (~2,000°F [~1,100°C]). A flow diagram depicting the
production of prebaked cells is shown in Figure 4.4.1-3. The high-temperature curing process
can generate POM emissions. Potentially, POM compounds can be emitted from the prebake
cell during the reduction process when the anodes are lowered into the reduction pot. However,
POM emissions from reduction are expected to be much less than those from Soderberg cells
because essentially all of the POM emissions have already been released during the preparation
and baking of anodes (U.S. EPA, 1979; Wallingford and Hee, 1985; Stricter, 1996).
Soderberg cell anodes are continuously lowered and baked by conductive heat
from the molten alumina bath rather than being premolded and baked. A coke and coal tar pitch
paste is packed into a metal shell over the bath. As the baked anode at the bottom of the shell is
consumed, more paste is added at the top of the shell. As the paste is consumed, potential POM
4-192
-------
Centre-break prebake anode cell
Anode beam
Alumina.
hopper
Gas off take
Frozen flux
and
alumina
Gat collection hoods
.Crust breaker
Side-break prebake anode cell
Steel
shell
Anode beam
Gas collection
hoods
Carbon anode
Vertical-stud Soderberg. cell
Anode beam
I
Molten flux '
Frozen flux and
alumina
Iron
cathode
bar
Burner
Anode skirt
Horizontal-stud Soderberg cell
Frozen flux
and \
alumina \
Figure 4.4.1-2. Types of Electrolytic Cells Used in Alumina Reduction
Source: IARC, 1984.
4-193
-------
COAL TAR PITCH
CRUSHER
CALCINED
PETROLED*
COKE
1 1
\-
r
-/
3
a
COARSE
t
t
1 1
t
1
TO POTLINE
STACK
O
Q.
I
o
ce.
ui
Figure 4.4.1-3. Flow Diagram Depicting the Production of Prebaked Cells
Source: U.S. EPA, 1979.
4-194
-------
emissions are released. Because the carbon paste is not baked prior to being placed in the pot,
POM emissions from a Soderberg cell (horizontal or vertical stud) reduction operation have the
potential to be much greater than those from a prebaked cell reduction operation.
An additional source of potential POM emissions associated with primary
aluminum production is aluminum casthouse operations, or the pouring, cooling, and shakeout of
aluminum castings (Gressel et al., 1988). Most commonly, aluminum foundries produce castings
using green sand molds. The evaporative casting (EPC) process may be used to produce
complex-shaped castings. In the EPC process, a low-density polystyrene foam facsimile of the
part to be cast is formed, coated with refractory wash, and packed in a flask with dry unbonded
sand. Introduction of molten metal causes the polystyrene to evaporate. Use of the EPC process
in the foundry industry has the potential for expansion because of its low cost and versatility
(Gressel et al., 1988).
Emissions control at primary aluminum reduction facilities (cell rooms or pot
rooms) is intended primarily for fluoride removal and involves efficient emissions capture and
removal. Emissions capture is generally accomplished by using precisely designed hooding and
ducting systems on reduction cells. The term hooding includes the use of classical draft hoods
and the use of movable doors, enclosures, and skirts. Primary emissions removal is achieved
through the use of dry scrubbing systems or wet scrubber/ESP systems. Two types of dry
scrubbing systems, fluidized-bed and injected alumina, are found in the industry, and both
contain baghouse equipment to collect PM from the chemical absorption scrubbing process.
These baghouses would be effective in removing particulate POM in the emission stream.
Standard design spray tower wet scrubbers and wet ESPs used in the series are
also effective primary control systems at aluminum reduction facilities. The ability of the
combination wet scrubbing/precipitation system to remove particulate POM should be equal to
that of the dry scrubbing/baghouses. In addition to being a primary control system for cell room
emissions, wet scrubbers are also used in some facilities as the primary control system for
producing prebake anodes (U.S. EPA, 1979; Stricter, 1996).
4-195
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In some primary aluminum installations, secondary control systems are used. The
predominant secondary system is a spray screen scrubber followed by a mist eliminator. The
term spray screen scrubber is applied to wet scrubbers in which the scrubbing liquor is sprayed
into a gas stream and onto screens or open-mesh filters enclosed in a plenum chamber
(U.S. EPA, 1979). The use of spray screen wet scrubbers for secondary emission control only
occurs at a few facilities. Rather, the predominant emission control technology currently in use
is to provide better capture of emissions at the reduction cells through hooding and shielding
improvements for the primary control system (Stricter, 1996).
Emission Factors
Emission factors were developed for five primary aluminum production
processes. Clement International Corporation presented PAH emissions data for a primary
aluminum smelter in the United States, which was based on the average of five testing programs
conducted from 1985 to 1991 (Clement International Corporation, 1992; State of Washington
DOE, 1985). Sampling and analytical methods were used to quantify both paniculate and
vaporous PAHs. The facility operated three potlines containing 280 pots with a production
capacity of approximately 200 tons per day. A separate manufacturing building was used to mix
coke and coal tar pitch into a dense paste to replenish the consumable carbon anode used in the
reduction process. The report indicates that there were no significant process changes during the
test data averaging period. PAH emissions were quantified for the paste preparation plant, the
horizontal stud Soderberg cells following a dry scrubber, and from the potroom roof vents.
Emissions data were also obtained from source testing performed for the
development of the Primary Aluminum Production MACT. The final MACT rule was published
on September 19,1997. The emission factors are based on testing at four aluminum facilities in
1994 (AmTest Air Quality, Inc., 1994a; 1994b; 1994c; 1994d). The testing for POM included
the use of a surrogate measure based on extracting the front and back half catches of a modified
Method 5 sampling train with methylene chloride. The compounds extracted by the methylene
chloride include the POM species of interest as well as some other compounds. In addition, the
individual POM species typically found in the pitch were quantified.
4-196
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PAH emissions were quantified for a paste preparation plant (with scrubbers and
baghouse), vertical stud Soderberg cells (followed by wet and dry scrubbers), horizontal stud
Soderberg cells (followed by dry scrubbers), secondary roof emissions (wet and dry scrubbers),
and an anode bake furnace with dry scrubber.
Tables 4.4.1-1 to 4.4.1-9 present the emission factors developed from the Clement
and MACT tests. Emission factors from the two data sets were averaged where overlap between
data points existed.
Pot gas emissions are controlled with a dry scrubber system, forcing the gases and
dusts through a bed of finely powdered alumina. Organics are adsorbed onto the alumina
particles in the dry scrubber, and alumina and other dust particles are captured by impaction. PM
escaping the scrubber is entrained by a baghouse in series. The alumina scrubbing medium and
dust collected in the baghouse are periodically recycled to the production process.
A toxic air emissions inventory conducted in Canada and the United States
reported PAH emission tactors for primary aluminum reduction using prebake cells
4-197
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TABLE 4.4.1 -1. PAH EMISSION FACTORS FOR PRIMARY ALUMINUM PRODUCTION:
PASTE PREPARATION, UNCONTROLLED
-PI
oo
SCC Number Emission Source Control Device Pollutant
3-03-001-99 Paste Preparation Plant None Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
B cnzo(ghi)perylene
Fluoranthene
Average Emission Factor
in Ib/ton (kg/Mg)a
2.57E-04
(1.28E-04)
9.53E-06
(4.74E-06)
9.53E-06
(4.74E-06)
9.53E-06
(4.74E-06)
1.24E-04
(6.16E-05)
9.53E-06
(4.74E-06)
9.53E-06
(4.74E-06)
6.04E-02
(3.00E-02)
2.86E-05
(1.42E-05)
7.15E-03
(3.55E-03)
9.53E-06
(4.74E-06)
2.36E-02
1.18E-02
Emission Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4 4.1-1. (Continued)
SCC Number Emission Source Control Device Pollutant
3-03-001-99 Paste Preparation Plant None Fluorene
(continued) (continued)
Naphthalene
Phenanthrene
Pyrcne
Benzo(e)pyrene
Dibenz(a,e)pyrene
Dibenz(a,i)pyrene
Dibenz(a,h)pyrene
Average Emission Factor
in Ib/ton (kg/Mg)a
1.76E-02
(8.73E-03)
1.64E-02
(8.18E-03)
4.85E-02
(2.41E-02)
4.48E-04
(2.23E-04)
9.53E-06
(4.74E-06)
9.53E-06
(4.74E-06)
9.53E-06
(4.74E-06)
9.53E-06
(4.74E-06)
Emission Factor
Rating
D
D
D
D
D
D
D
D
"Emission factors are in lb/(kg) of pollutant emitted per ton (Mg) of aluminum produced.
Source: Clement International Corporation, 1992.
-------
TABLE 4.4.1-2. PAH EMISSION FACTORS FOR PRIMARY ALUMINUM PRODUCTION:
PASTE PREPARATION, BAGHOUSE CONTROLLED
SCC Number Emission Source Control Device Pollutant
3-03-001-99 Paste Preparation Plant Baghouse Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
t-
O Dibenz(a,h)anthracene
Indeno(l ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Average Emission Factor in
Ib/ton (kg/Mg)a
1.2E-06
(6.00E-07)
1.1E-06
(5.50E-07)
2.2E-06
(1.1E-06)
7.5E-07
(3.75E-07)
1.8E-06
(9.0E-07)
4.1E-07
(2.05E-07)
9.4E-07
(4.7E-07)
4.1E-07
(2.05E-07)
2.2E-07
(1.1E-06)
2.8E-07
(1.40E-07)
8.7E-07
(4.35E-07)
2.3E-06
1.15E-06
Emission Factor
Rating
Ub
Ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
(continued)
-------
TABLE 4.4.1-2. (Continued)
%
SCC Number Emission Source Control Device Pollutant
3-03-001-99 Paste Preparation Plant Baghouse Fluorene
(continued) (continued) (continued)
Naphthalene
Phenanthrene
Pyrene
Benzo(e)pyrene
2-Chloronaphthalene
2-Mei hy Inaphthalene
Perylene
Average Emission Factor in
Ib/ton (kg/Mg)a
3.5E-07
(1.75E-07)
5.7E-07
(2.85E-07)
1.2E-06
(6.00E-07)
2.1E-06
(1.05E-06)
l.OE-06
(5.00E-07)
3.7E-07
(1.85E-07)
4.5E-07
(2.25E-07)
4.7E-07
(2.35E-07)
Emission Factor
Rating
Ub
Ub
ub
ub
ub
ub
ub
ub
"Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of paste produced.
bFactor rating of "U" is not indicative of poor data, but reflects the fact that source test reports were not available for extensive review prior to L&E
publication.
Source: AmTest Air Quality, Inc., 1994b; Entropy, Inc., 1994.
-------
TABLE 4.4.1-3. PAH EMISSION FACTORS FOR PRIMARY ALUMINUM PRODUCTION:
PASTE PREPARATION, DRY SCRUBBER CONTROLLED
£
s
SCC Number Emission Source Control Device Pollutant
3-03-001-99 Paste Preparation Plant Dry Scrubber Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthenc
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Average Emission Factor
in Ib/ton (kg/Mg)a
1.55E-05
(7.75E-06)
8.10E-07
(4.05E-07)
1.47E-06
(7.35E-07)
7.95E-07
(3.98E-07)
1.08E-05
(5.40E-06)
3.53E-07
(1.76E-07)
2.78E-07
(1.39E-07)
1.02E-03
(5.08E-04)
1.02E-05
(5.09E-06)
2.55E-04
(1.27E-04)
2.48E-07
(1.24E-07)
5.26E-04
(2.63E-04)
Emission Factor
Rating
Ub
Ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
(continued)
-------
TABLE 4.4.1-3. (Continued)
SCC Number Emission Source Control Device Pollutant
3-03-001-99 Paste Preparation Plant Dry Scrubber Fluorene
(continued) (continued) (continued)
Naphthalene
Phenanthrene
Pyrene
Carbazole
2- Methyl naphthalene
Benzo(e)pyrene
Average Emission Factor
in Ib/ton (kg/Mg)a
1.01E-03
(5.03E-04)
4.45E-06
(2.23E-06)
1.56E-03
(7.78E-04)
2.16E-04
(1.08E-04)
l.OOE-04
(5.00E-05)
5.95E-06
(2.98E-06)
5.10E-07
(2.55E-07)
Emission Factor
Rating
Ub
Ub
ub
ub
ub
ub
ub
"Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of paste produced.
bFactor rating of "U" is not indicative of poor data, bui reflects the fact that source test reports were not available for extensive review prior to L&E
publication.
Source: AmTest Air Quality, Inc., 1994b; Entropy, Inc., 1994.
-------
TABLE 4.4.1-4. PAH EMISSION FACTORS FOR PRIMARY ALUMINUM PRODUCTION:
HORIZONTAL-STUD SODERBERG CELLS
2
SCC Number Emission Source Control Device Pollutant
3-03-001-02 Horizontal Soderberg Cell Dry Scrubber Benz(a)anthracene
Benzo(a)pyrene
B enzo(b)fl uoranthene
B c nzo(k)fl uoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi )perylene
Fluoranthene
Average Emission
Factor in Ib/ton
(kg/Mg)a
2.05E-03
(1.02E-03)
1.24E-03
(6.20E-04)
I.34E-03
(6.70E-04)
1.20E-03
(6.00E-04)
3.20E-03
(1.60E-03)
2.10E-03
(1.05E-03)
2.14E-03
(1.07E-03)
2.15E-01
(1.08E-01)
1.27E-02
(6.35E-03)
1.96E-01
(9.78E-02)
2.14E-03
(1.07E-03)
1.08E-01
(5.38E-02)
Emission Factor
Range in Ib/ton
(kg/Mg)
4.00E-04 - 3.69E-03
(2.00E-04-1.85E-03)
1.00E-04-2.38E-03
(5.00E-05-1.19E-03)
3.00E-04 - 2.38E-03
(1.50E-04- 1.19E-03)
1.00E-04-2.30E-03
(5.00E-05-1.15E-03)
1.00E-03-5.40E-03
(5.00E-04 - 2.70E-03)
2.00E-05-4.18E-03
(l.OOE-05 - 2.09E-03)
1.00E-04-4.18E-03
(5.00E-05 - 2.09E-03)
l.OOE-03 - 4.29E-01
(5.00E-04-2.15E-01)
l.OOE-04 - 2.53E-02
(5.00E-05- 1.27E-02)
4.00E-03 - 3.87E-01
(2.00E-03- 1.94E-01)
l.OOE-04- 4. 18E-03
(5.00E-05 - 2.09E-03)
3.50E-02- 1.80E-01
C1.75E-02-9.00E-02)
Emission
Factor
Rating
Ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
(continued)
-------
TABLE 4 4.1-4. (Continued)
K>
8
SCC Number Emission Source Control Device Pollutant
3-03-001-02 Horizontal Soderberg Cell Dry Scrubber Fluorene
(continued) (continued) (continued)
Naphthalene
Phenanthrene
Pyrene
Benzo(e)pyrene
Dibenz(a,e)pyrene
Dil>enz(a,i)pyrene
Dibenz(a,h)pyrene
Carbazole
2-Methylnaphthalene
Average Emission
Factor in Ib/ton
(kg/Mg)a
1.43E-01
(7.I5E-02)
2.07E-01
(1.04E-01)
6.06E-01
(3.03E-01)
8.40E-02
(4.20E-02)
4.18E-03
(2.09E-03)
4.60E-03
(2.29E-03)
4.60E-03
(2.29E-03)
4.60E-03
(2.29E-03)
l.OOE-03
(5.00E-04)
l.OOE-03
(5.00E-041
Emission Factor
Range in Ib/ton
(kg/Mg)
2.90E-02 -
(1.45E-02-
2.00E-04 -
(l.OOE-04-
3.20E-01 -
(1.60E-01 -
2.80E-02 -
(1.40E-02-
l.OOE-04-
(5.00E-05 -
-
-
-
-
--
2.57E-01
1.29E-01)
4.14E-01
2.07E-01)
8.91E-01
4.46E-01)
1.40E-01
7.00E-02)
4.18E-03
2.09E-03)
-
-
-
-
-
Emission
Factor
Rating
Ub
Ub
ub
ub
ub
ub
ub
ub
ub
ub
'Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of aluminum produced.
''Factor rating of "U" is not indicative of poor data, but reflects the fact that soui ce test reports were notaavailable for extensive review prior to L&E
publication.
Source: Clement International Corporation, 1992; AmTest Air Quality, Inc., 1994a.
"—" means no data available.
-------
TABLE 4.4.1-5. PAH EMISSION FACTORS FOR PRIMARY ALUMINUM PRODUCTION:
VERTICAL-STUD SODERBERC. CELLS, DRY SCRUBBER CONTROLLED
SCC Number Emission Source Control Device Pollutant
3-03-001-02 Vertical Soderberg Cell Dry Scrubber Bcnz(a)anthracene
Bcnzo(a)pyrene
Benzo(b)fluoranthene
Bcnzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno(l ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
B cnzo(ghi)perylene
Fluoranthene
Average Emission Factor
in Ib/ton (kg/Mg)a
9.4E-06
(4.70E-06)
4.2E-06
(2.10E-06)
1.2E-05
(6.00E-06)
4.4E-06
(2.20E-06)
2.0E-05
(l.OOE-05)
4.5E-06
(2.25E-06)
4.4E-06
(2.2E-06)
5.7E-06
(2.85E-06)
3.4E-06
(1.70E-06)
3.0E-06
(1.50E-06)
4.7E-06
(2.35E-06)
2.8E-04
(1.4E-04)
Emission Factor
Rating
Ub
Ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
(continued)
-------
TABLE 4 4.1-5. (Continued)
4^.
§
SCC Number Emission Source Control Device Pollutant
3-03-001-02 Vertical Soderberg Cell Dry Scrubber Flnorene
(continued) (continued) (continued)
Naphthalene
Phenanthrene
Pyrene
Benzo(e)pyrene
2-C 'hloronaphthalene
2-Methylnaphthalene
Perylene
Average Emission Factor
in Ib/ton (kg/Mg)a
1.1E-05
(5.50E-06)
2.7E-05
(1.35E-05)
3.0E-04
(1.50E-04)
1.4E-04
(7.00E-05)
4.6E-06
(2.3E-06)
5.5E-06
(2.75E-06)
4.5E-06
(2.25E-06)
4.2E-06
(2.1E-06)
Emission Factor
Rating
Ub
ub
U"
ub
ub
ub
ub
ub
"Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of aluminum produced.
''Factor rating of "U" is not indicative of poor data, but reflects the fact that soui ce test reports were not available for extensive review prior to L&E
publication.
Source: Entropy, Inc., 1994.
-------
TABLE 4.4.1-6. PAH EMISSION FACTORS FOR PRIMARY ALUMINUM PRODUCTION:
VERTICAL-STUD SODERBERG CELLS, WET SCRUBBER WITH DRY SCRUBBER CONTROLLED
10
o
oo
SCC Number Emission Source Control Devii c Pollutant
3-03-001-02 Vertical Soderberg Cell Wet Scrubber following Dry Benz(a)anthracene
Scrubber
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthenc
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Average Emission
Factor in Ib/ton
(kg/Mg)a
6.6E-06
(3.3E-06)
4.8E-06
(2.40E-06)
l.OE-05
(5.00E-06)
4.9E-06
(2.45E-06)
2.7E-05
(1.35E-05)
5.0E-06
(2.50E-06)
4.7E-06
(2.35E-06)
6.5E-06
(3.25E-06)
3.7E-06
(1.85E-06)
3.6E-06
(1.80E-06)
5.3E-06
(2.65E-06)
1.1E-04
(5.50E-05)
Emission Factor
Rating
Ub
Ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
(continued)
-------
TABLE 4 4.1-6. (Continued)
bO
SCC Number Emission Source Control Device Pollutant
3-03-001-02 Vertical Soderberg Cell Wet Scrubber following Dry Fluorene
(continued) (continued) Scrubber (continued)
Naphthalene
Phenanthrene
Pyrene
Benzo(e)pyrene
2-Chloronaphthalene
2-Methylnaphthalene
Perylene
Average Emission
Factor in Ib/ton
(kg/Mg)1
6.8E-06
(3.4E-06)
4.6E-05
(2.30E-05)
1.2E-04
(6.00E-05)
1.8E-05
(9.00E-06)
4.8E-06
(2.4E-06)
9.2E-06
(4.60E-06)
5.7E-06
(2.85E-06)
4.8E-06
(2.4E-06)
Emission Factor
Rating
Ub
U"
ub
ub
ub
ub
ub
ub
"Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of aluminum produced.
bFactor rating of "U" is not indicative of poor data, but reflects the fact that source test reports were not available for extensive review prior to L&E
publication.
Source: Entropy, Inc., 1994.
-------
TABLE 4.4.1-7. PAH EMISSION FACTORS FOR PRIMARY ALUMINUM PRODUCTION: POTROOMS
-fc.
o
SCC Number Emission Source Control Device Pollutant
3-03-001-07 Potroom Roof Vents None Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chryscne
Diben /.(a.h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Average Emission Factor in
Ib/ton (kg/Mg)a
7.23E-02
(3.59E-02)
3.63E-02
(1.80E-02)
8.07E-02
(4.01E-02)
3.79E-02
(1.88E-02)
1.90E-01
(9.45E-02)
1.21E-02
(6.01E-03)
1.64E-02
(8.10E-03)
1.53E-01
(7.60E-02)
3.70E-02
(1.84E-02)
6.43E-002
(3.20E-02)
1.73E-02
(8.60E-03)
5.50E-01
(2.73E-01)
Emission Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.4.1-7. (Continued)
N)
SCC Number Emission Source Control Device Pollutant
3-03-001-07 PotroomRoof Venis None Fluorene
(continued) (continued)
Naphthalene
Phenanthrene
Pyrene
Benzo(e)pyrene
Dibenz(a,e)pyrene
Dibenz(a,i)pyrene
Dibenz(a,h)pyrene
Average Emission Factor in
Ib/ton (kg/Mg)a
7.51E-02
(3.73E-02)
1.31E-01
(6.49E-02)
9.40E-01
(4.68E-01)
3.79E-01
(1.88E-01)
4.58E-02
(2.28E-02)
1.05E-02
(5.22E-03)
1.05E-02
(5.22E-03)
1.05E-02
(5.22E-03L
Emission Factor
Rating
D
D
D
D
D
D
D
D
'Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of aluminum produced.
Source: Clement International Corporation, 1992.
-------
TABLE 4.4.1-8. PAH EMISSION FACTORS FOR PRIMARY ALUMINUM PRODUCTION:
SECONDARY ROOF VENTS, DRY SCRUBBER CONTROLLED
t
SCC Number Emission Source Control Device Pollutant
3-03-001-07 Secondary Roof Vents Dry Scrubber Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno(l,2,3-cd)pyrene
Acenaphthene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Average Emission Factor in
ll>/ton (kg/Mg)a
5.01E-03
(2.51E-03)
1.52E-03
(7.61E-04)
5.78E-03
(2.89E-03)
1.77E-03
(8.84E-04)
1.28E-02
(6.42E-03)
5.22E-04
(2.61E-04)
1.26E-03
(6.32E-04)
7.21E-05
(3.61E-05)
1.02E-03
(5.11E-04)
1.26E-03
(6.31E-04)
2.40E-02
(1.20E-02)
1.20E-04
(5.98E-05)
Emission Factor
Rating
Ub
U"
ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
(continued)
-------
TABLE 4.4.1-8. (Continued)
SCC Number Emission Source Control Device Pollutant
3-03-001-07 Secondary Roof Vents Dry Scrubber Naphthalene
(continued) (continued) (continued)
Phenanthrene
Pyrene
Carbazole
2-Methylnaphthalene
2-Chloronaphthalene
Average Emission Factor in
Ib/ton (kg/Mg)'
7.21E-05
(3.61E-05)
9.01E-03
(4.50E-03)
1.90E-02
(9.50E-03)
1.28E-03
(6.42E-04)
9.71E-05
(4.86E-05)
5.96E-05
(2.98E-05)
Emission Factor
Rating
Ub
ub
ub
ub
ub
,!o 'Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of aluminum pt oduced.
^ ''Factor rating of "U" is not indicative of poor data, but reflects the fact that source test reports were not available for extensive review prior to L&E
publication.
Source: AmTest Air Quality, Inc., 1994a; 1994b; 1994c.
-------
TABLE 4.4.1-9. PAH EMISSION FACTORS FOR PRIMARY ALUMINUM PRODUCTION:
SECONDARY ROOF VENTS, WET SCRUBBER CONTROLLED
N)
>—*
-^.
SCC Number Emission Source Control Device Pollutant
3-03-001-07 Secondary Roof Vents Wet Scrubber Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno(l,2,3-cd)pyrene
Acenaphthene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Average Emission Factor
in Ib/ton (kg/Mg)a
2.30E-02
(1.15E-02)
1.20E-02
(6.00E-03)
3.00E-02
(1.50E-02)
8.40E-03
(4.20E-03)
4.00E-02
(2.00E-02)
3.00E-03
(1.50E-03)
6.60E-03
(3.30E-03)
1.30E-03
(6.50E-04)
1.90E-02
(9.50E-03)
8.50E-03
(4.25E-03)
1.20E-01
(6.00E-02)
4.70E-03
(2.35E-03)
Emission Factor
Rating
Ub
U"
ub
ub
ub
ub
ub
ub
ub
ub
u"
ub
(continued)
-------
TABLE 4.4.1-9. (Continued)
SCC Number Emission Source Control Device Pollutant
3-03-001-07 Potroom Roof Vents None Phenanthrene
Pyrene
Benzo(e)pyrene
Perylene
Average Emission Factor
in Ib/ton (kg/Mg)a
1.20E-01
(6.00E-02)
9.30E-02
(4.65E-02)
1.30E-02
(6.50E-03)
3.10E-03
(1.55E-Q31
Emission Factor
Rating
Ub
Ub
ub
ub
"Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of aluminum produced.
''Factor rating of "U" is not indicative of poor data, but reflects the fact that source test reports were not available for extensive review prior to L&E
publication.
Source: Entropy, Inc., 1994.
to
-------
(Johnson et al., 1990). The emission factor data came from a 1986 study of solid adsorber
collection devices (Houle, 1986). The tested process was controlled with dry scrubbers. These
data and those from the proposed MACT rule are presented in Table 4.4.1-10.
The MACT emission factors for two anode bake furnaces controlled by dry
alumina scrubbers are presented in Table 4.4.1-11. Emissions from prebake cell preparation
were not quantified.
Total PAH emission factors (the reference does not present individual PAH
species or indicate exactly which PAH species are included in "total PAH") from horizontal and
vertical Soderberg reduction cells at a primary aluminum smelter were reported in a Swedish test
report (Alfheim and Wikstrom, 1984). Total PAH emissions from the vertical Soderberg process
(from pot gas dry scrubber and building ventilation) were 1.54 Ib/ton (0.7 kg/ton), as opposed to
9.68 Ib/ton (4.4 kg/ton) from the horizontal Soderberg process. The PAH emissions of the
horizontal Soderberg process exhibited a higher fraction in the particulate phase than in the vapor
phase. Conversely, PAH emissions from the vertical Soderberg process were predominantly in
vapor form (Alfheim and Wikstrom, 1984).
Emission factors for the pouring, cooling, and shakeout of aluminum castings
were reported (Gressel et al., 1988). A pilot test plant was engineered to quantify emissions of
aerosol and gaseous PAHs from the green sand and evaporative casting (EPC) process. Emission
factors for both processes are presented in Table 4.4.1-12.
Source Locations
As of December 1992, there were 23 primary aluminum reduction plants in the
United States operated by 13 different companies. Washington State has seven
plants, the most of any state in the country. A complete list of all 23 facilities is given in
Table 4.4.1-13 (Plunkert and Sehnke, 1993).
4-216
-------
TABLE 4.4.1-10. PAH EMISSION FACTORS FOR PRIMARY ALUMINUM PRODUCTION: PREBAKED CELL
4^-
^J
SCC Number Emission Source Control Device Pollutant
3-03-001-01 Prebaked Anode Cell Dry Scrubber Benz(a)anthracene
Benzo(a)pyrene
B enzofluoran t henes
Chrysene
Dibenz(a,h)anthracene
Indeno(l,2,3-ed)pyrene
Acenaphthylene
Anthracene and
Phenanthrene
Benzo(ghi)pei ylene
Fluoranthene
Fluorene
Naphthalene
Average Emission Factor in
Ib/ton (kg/Mg)a
1 26E-02
(629E-03)
5 74E-03
(2.87E-03)
1.94E-02
(9.70E-03)
1 .79E-02
(8.93E-03)
1.14E-03
(5.70E-04)
1.94E-03
(9.70E-04)
5.41E-03
(2.71E-03)
5.18E-02
(2.59E-02)
2.74E-03
(1.37E-03)
4.94E-02
(2.47E-02)
1.28E-03
(6.40E-04)
2.00E-05
(l.OOE-05)
Emission Factor
Range in Ib/ton (kg/Mg)
3.80E-05 - 3.76E-02
(1.90E-05-1.88E-02)
l.OOE-05- 1.72E-02
(5.00E-06 - 8.60E-03)
l.OOE-05 -5.82E-02
(5.00E-06 - 2.91E-02)
8.20E-05 - 5.32E-02
(4.10E-05-2.66E-02)
5.00E-06 - 3.40E-03
(2.50E-06- 1.70E-03)
l.OOE-05 -8.80E-03
(5.00E-06 - 4.40E-03)
l.OOE-05- 1.62E-02
(5.00E-06-8.10E-03)
l.OOE-05 -1.55E-01
(5.00E-06 - 7.75E-02)
l.OOE-05 - 8.20E-03
(5.00E-06-4.10E-03)
4.70E-05-1.48E-01
(2.35E-05 - 7.40E-02)
l.OOE-05 -3.80E-03
(5.00E-06-1.90E-03)
l.OOE-05 -3.00E-05
(5.00E-06-1.50E-05)
Emission
Factor
Rating
Ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
(continued)
-------
TABLE 4.4.1-10. (Continued)
to
i—*
oo
SCC Number Emission Source Control Device
3-03-001-01 Prebaked Anode Cell Dry Scrubber
(continued) (continued) (continued)
Pollutant
Pyrene
Benzo(e)pyrene
2-Methylnaphthalenc
Retene
Average Emission Factor in
Ib/ton (kg/Mg)a
4.14E-02
(2.07E-02)
2.68E-02
(1.34E-02)
3.00E-05
(1.50E-05)
1.50E-05
(7.50E-06)
Emission Factor
Range in Ib/ton (kg/Mg)
4.10E-05-1.24E-01
(2.05E-05 - 6.20E-02)
—
l.OOE-05 - 5.00E-05
(5.00E-06 - 2.50E-05)
LOOE-05 - 2.00E-05
(5.00E-06- l.OOE-05)
Emission
Factor
Rating
Ub
Ub
ub
ub
"Emission factors are in Ib (kg) pollutant emitted per ton (Mg) of aluminum produced.
''Factor rating of "U" is not indicative of poor data, but reflects the fact that source test reports were not available for extensive review prior to L&E
publication.
Source: Johnson et al., 1990; AmTest Air Quality, Inc., 1994c; AmTest Air Quality, Inc., 1994b.
"—" means data not available.
-------
TABLE 4.4.1-11. PAH EMISSION FACTORS FOR PRIMARY ALUMINUM PRODUCTION:
ANODE BAKE FURNACE
SCC Number Emission Source Control Device Pollutant
3-03-001-05 Anode Bake Furnace Dry Scrubber Ben/.(a)anthracene
Ben/.o(a)pyrene
Beruo(b)fluoranthene
Ben/o(k)fluoranthene
Chrysene
f"
£f Dibcnz(a,h)anthracene
VO
Indcno(l,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Phenanthrene
Ben /.o(ghi)pery lene
Average Emission Factor
in Ib/ton (kg/Mg)a
5.75E-05
(2.88E-05)
5.80E-05
(2.90E-05)
5.42E-04
(2.71E-04)
1.12E-04
(5.60E-05)
5.60E-04
(2.80E-04)
5.36E-05
(2.68E-05)
2.12E-04
(1.06E-04)
5.95E-06
(2.98E-06)
1.10E-05
(5.48E-06)
2.98E-05
(1.49E-05)
1.49E-02
(7.45E-03)
5.10E-04
(2.55E-04)
Emission Factor
Rating
Ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
ub
(continued)
-------
TABLE 4.4.1-11. (Continued)
SCC Number Emission Source
3-03-001-05 Anode Baked Furnace
(continued) (continued)
. aEmission factors are in Ib (kg) pollutant emitted per ton
Control Device Pollutant
Dry Scrubber Fluoranthene
(continued)
Fluorene
Naphthalene
Pyrene
Carbazole
2-Methylnaphthalene
(Mg) of anode produced.
i^ ''Factor rating of "U" is not indicative of poor date, but reflects the fact that source test reports were not available
££ publication.
Source: AmTest Air Quality, Inc., 1994b; 19')4c.
Average Emission Factor
in Ib/ton (kg/Mg)a
3.75E-03
(1.88E-03)
5.44E-04
(2.72E-04)
1.39E-05
(6.95E-06)
6.80E-04
(3.40E-04)
2.20E-05
(1.10E-05)
1.10E-05
(5.48E-06)
for extensive review prior to L&E
Emission Factor
Rating
Ub
Ub
ub
ub
ub
ub
-------
TABLE 4.4.1-12. PAH EMISSION FACTORS FOR PRIMARY ALUMINUM
PRODUCTION: CASTING OPERATIONS3
10
to
SCC Number Emission Source Control Device Pollutant
3-03-001-99 EPC Casting Operations0 None Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthcnc
Benzo(k)fluoranthene
Chrysene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Bcnzo(e)pyrene
Average Emission
Factor in Ib/ton
(kg/Mg)b
4.40E-05
(2.20E-05)
1.22E-04
(6.10E-05)
1.38E-04
(6.90E-05)
4.20E-05
(2.10E-05)
1.80E-05
(9.00E-06)
4.80E-04
(2.40E-04)
6.20E-05
(3.10E-05)
3.00E-05
(1.50E-05)
6.80E-OS
(3.40E-05)
Emission Factor
Rating
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.4.1-12. (Continued)
Average Emission
Factor in Ib/ton
SCC Number Emission Source Control Device Pollutant (kg/Mg)b
3-03-001-99 Green Sand Casting None Anthracene 3.20E-04
Operation (1.60E-04)
Fluorene 4.60E-04
(2.30E-04)
Naphthalene 1.14E-02
(5.70E-03)
Emission Factor
Rating
E
E
E
'Emissions from pouring, cooling, and shakeout of aluminum castings.
bEmission factors are in Ib (kg) of pollutant emitted per ton (Mg) of aluminum cast.
cEvaporative pattern casting process (lost foam process).
Source: Gressel et al., 1988.
to
-------
TABLE 4.4.1-13. PRIMARY ALUMINUM PRODUCTION FACILITIES
IN THE UNITED STATES IN 1992
Facility
Location
Alcan Aluminum Corporation
Alumax, Inc.
Aluminum Company of America
Columbia Aluminum Corporation
Columbia Falls Aluminum Company
Kaiser Aluminum and Chemical Corporation
National-Southwire Aluminum Company
Noranda Aluminum, Inc.
Northwest Aluminum Corporation
Ormet Corporation
Ravenswood Aluminum Corporation
Reynolds Metals Company
Vanalco Inc.
Sebree, KY
Mount Holly, SC
Frederick, MD
Ferndale, WA
Alcoa, TN
Badin, NC
Evansville, IN
Massena, NY
Rockdale, TX
Wenatchee, WA
Goldendale, WA
Columbia Falls, MT
Mead, WA
Tacoma, WA
Hawesville, KY
New Madrid, MO
The Dalles, OR
Hannibal, OH
Ravenswood, WV
Longview, WA
Massena, NY
Troutdale, OR
Vancouver, WA
NOTE: This list is subject to change as market conditions and facility ownership changes, plants are
closed down, etc. The reader should verify the existence of specific facilities by consulting current
lists and/or the plants themselves. The level of POM emissions from any given facility is a
function of variables such as capacity, throughput, and control measures, and should be
determined through direct contacts with plant personnel.
Source: Plunkert and Sehnke, 1993.
4-223
-------
SECTION 4.4.1 REFERENCES
Alfheim, I., and L. Wikstrom. "Air Pollution from Aluminum Smelting Plants 1. The Emission
of Polycyclic Aromatic Hydrocarbons and of Mutagens from an Aluminum Smelting Plant Using
the Soderberg Process." Toxicological and Environmental Chemistry 8(l):55-72. 1984.
AmTest Air Quality, Inc. "Kaiser Aluminum and Chemical Corporation Method 5/POM and
13B Testing: March 1-8,1994, Tacoma, Washington." Prepared for Kaiser Aluminum and
Chemical Corporation, Tacoma, Washington, pp 1-47. 1994a.
AmTest Air Quality, Inc. "Kaiser Aluminum and Chemical Corporation Method 5/POM and
13B Testing: March 15-24,1994, Mead, Washington." Prepared for Kaiser Aluminum and
Chemical Corporation, Mead, Washington, pp 1-99. 1994b.
AmTest Air Quality, Inc. "Noranda Aluminum, Inc. Method 5/POM and 13B Testing:
September 14-20, 1994, New Madrid, Missouri." Prepared for Noranda Aluminum, Inc, New
Madrid, Missouri, pp. 1-62. 1994c.
AmTest Air Quality, Inc. "Washington Department and Kaiser Aluminum and Chemical
Corporation Method 5/POM and 13B Testing: May 2-5 1994, Mead, Washington." Prepared for
Kaiser Aluminum and Chemical Corporation, Mead, Washington, pp. 1-33. 1994d.
Clement International Corporation. Draft Health Risk Assessment: Kaiser Aluminum Smelter.
Tacoma. Washington. Prepared for Kaiser Aluminum and Chemical Company, Tacoma,
Washington, pp. 2-1 to 2-10 and 4-1 to 4-19. 1992.
Entropy, Inc. "Emissions Measurement Test Report: Northwest Aluminum Facility." Prepared
for Northwest Aluminum Corporation, The Dalles, Oregon, p. 77. 1994.
Gressel, M.G., D.M. O'Brien, and R.D. Tenaglia. "Emissions from the Evaporative Casting
Process." Appl. Ind. Hyg.. Volume 3. No. l,pp. 11-17. 1988.
Houle, G. "Emissions des Hydrocarbures Polycyclic Aromatiques Provenant de L"Aluminerce
de la Compagnie Secal a Jonquiere." Ministere de L'Environment, Direction
deL'Assainissementde L'Air. 1986.
International Agency for Research on Cancer (IARC). IARC Monographs on the Evaluation of
Carcinogenic Risk of Chemicals to Humans. Volume 34: Polynuclear Aromatic Compounds.
Part 3. Industrial Exposures in Aluminum Production. Coal Gasification. Coke Production. Iron
and Steel Founding. International Agency for Research on Cancer, p. 40. 1984.
Johnson, N.D., M.T. Scholtz, V. Cassaday, and K. Davidson. MOE Toxic Chemical Emission
Inventory for Ontario and Eastern North America. Prepared for the Air Resources Branch,
Ontario Ministry of the Environment, Rexdale, Ontario. Draft Report No. P.89-50-5429/OG.
p. 80. 1990.
4-224
-------
Plunkert, P.A., and E.D. Sehnke. "Aluminum, Bauxite, and Alumina." In: Minerals Yearbook.
1992. U.S. Bureau of Mines, Washington, DC. p. 21. 1993.
Siebert, P.C. et al. Preliminary Assessment of the Sources. Control and Population Exposure to
Airborne Polycyclic Organic Matter (POM1) as Indicated by Benzofa'tpyrene fBaP). Prepared for
U.S. Environmental Protection Agency, Pollutant Strategies Branch, Office of Air Quality
Planning and Standards, Research Triangle Park, North Carolina. EPA Contract
No. 68-02-2836. pp. 82-85. 1978.
State of Washington. Source Test Report: 85-14. Kaiser Aluminum and Chemical Corporation.
Tacoma. Washington. Potline No. 4. Emissions of Organic Aromatic Compounds. Department
of Ecology, Washington. 18pp. 1985.
Stricter, R.P., The Aluminum Association, Letter to D. Beauregard, U.S. Environmental
Protection Agency. January 15,1996.
U.S. Environmental Protection Agency. Primary Aluminum Draft Guidelines for Control of
Fluoride Emissions from Existing Primary Aluminum Plants. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. EPA Report No. 450/2-78-049a. 1979.
Wallingford, K.M., and S.S. Que Hee. "Occupational Exposure to Benzo(e)pyrene." In:
Polynuclear Aromatic Hydrocarbons: Mechanisms. Methods, and Metabolism. Proceedings of
the Eighth International Symposium on Polynuclear Aromatic Hydrocarbons. Columbus, Ohio,
1983. M. Cooke and A.J. Dennis, eds. Battelle Press, Columbus, Ohio. 1985.
4-225
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4.4.2 Sintering in the Iron and Steel Industry
Process Description
In the iron and steel industry, the sintering process converts materials such as fine
iron ore concentrates, blast furnace flue dust, mill scale, turnings, coke fines, and limestone fines
into an agglomerated product that is suitable for use as blast furnace feed material. Sintering is
necessary to prevent fine iron ore material (whether in natural or concentrated ores) from being
blown out of the top of a blast furnace (Kelly, 1983; U.S. EPA, 1981). A typical sintering
operation is illustrated in Figure 4.4.2-1.
Sintering begins with mixing iron-bearing materials with coke or coal fines,
limestone fines (a flux material), water, and other recycled dusts (e.g., blast furnace flue dust) to
obtain the desired sinter feed composition. The prepared feed is distributed evenly onto one end
of a continuous traveling grate or strand. After the feed has been deposited on the strand, the
coke on the mixture is ignited by a gas- or oil-fired furnace. After the coke has been ignited, the
traveling strand passes over windboxes, where an induced downdraft maintains combustion in
the sinter bed. This combustion creates sufficient temperatures (2,400 to 2,700°F [1,300 to
1,500°C]) to fuse the metal particles into a porous clinker that can be used as blast furnace feed
(Kelly, 1983; U.S. EPA, 1981). Approximately 2.5 tons of raw materials, including water and
fuel, are required to produce one ton of product sinter (U.S. EPA, 1995).
After the sintering process is completed, the sintered material is discharged from
the sinter strand into a crushing operation. Following crushing, the broken sinter falls onto sizing
screens, where undersize material is collected and recycled to the start of the sintering process.
The oversize sinter clinker is then sent to a cooling process. The most common types of sinter
coolers include circular or straight-line moving beds, quiescent beds, or shafts. Air or water is
used as the cooling medium in these coolers, with air being prevalent in newer plants and water
being dominant in older plants. The cooled sinter is either sent directly to a blast furnace, sent to
storage, or screened again prior to blast furnace usage to obtain a more precise size specification
(Kelly, 1983; U.S. EPA, 1981).
4-226
-------
POTENTIAL POH EMISSIONS
FROM W1NDBOX
POTENTIAL POM EMISSIONS
FROM DISCHARGE
POTENTIAL POM EMISSIONS FROM
SCREENING AND TRANSFER POINTS
.A-
TO BLAST
FURNACE
3,
I
ffi
Figure 4.4.2-1. Conflgunttion of a Typical Sintering Facility
Source: U.S. EPA , 1977.
-------
POM emissions originate in the sintering process from the burning of coke and
potentially oily materials in the sinter feed. POM emissions may be released from the sinter
machine windbox, the sinter machine discharge point, and the sinter product processing
operations (i.e., crushing, screening, and cooling). Because of the high temperatures used in
sintering operations, it is probable that sinter plant POM emissions are in both gaseous and
particulate forms (Kelly, 1983; Siebert et al., 1978).
Emissions control at sintering facilities typically involves emissions collection
and conveyance to a standard particulate control device such as a baghouse, ESP, or wet
scrubber. If substantial quantities of POM emissions are in gaseous form, wet scrubbers would
likely be most efficient in reducing total POM because gaseous compounds would be condensed
in the scrubber (Kelly, 1983; U.S. EPA, 1981; U.S. EPA, 1977; Siebert et al., 1978).
Emission Factors
Emission factor data for PAHs from sintering operations were not available at the
time this report was prepared. The only available information reported an emission factor for
benzo(a)pyrene (BaP) in the range of 1.2 x 106 to 2.2 x 10'3 Ib/ton (600 ng/Mg to 1.1 g/Mg) of
sinter feed processed. The precise source of the emissions (windbox, discharge point, etc.) and
the control status of the source are not defined in the literature. Available data did not indicate
whether the range of emission factors represented only particulate BaP or particulate and gaseous
BaP emissions (Siebert et al., 1978). Therefore, this emission factor should be applied with
caution, recognizing the uncertainty in its development and low confidence in its quality.
Source Locations
Iron and steel sintering facilities are located in conjunction with the operation of
iron and steel blast furnaces. According to EPA, there were 11 integrated iron and steel
manufacturing facilities in the United States with sintering operations in 1993 (Mulrine
Telecon, 1994). The names and locations of these facilities are listed in Table 4.4.2-1.
4-228
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TABLE 4.4.2-1. LOCATIONS OF IRON AND STEEL INDUSTRY
SINTER PLANTS IN 1993
Company Plant Location
Arnco Steel Ashland, KY
Arnco Steel Middletown, OH
Bethlehem Steel Bums Harbor, IN
Bethlehem Stee! Sparrows Point, MD
Geneva Steel Orem, UT
Inland Steel East Chicago, IN
LTV Steel East Chicago, IN
USX Gary, IN
NCI Steel Youngstown, OH
Weirton Steel Weirton, WV
Wheeling-Pittsburgh Steubenville, OH
NOTE: This list is subject to change as market conditions change, facility ownership changes, plants are
closed down, eic. The reader should verify the existence of particular facilities by consulting
current list and/or the plants themselves.
Source: Mulrine Telecon, 1994.
4-229
-------
SECTION 4.4.2 REFERENCES
Kelly, M.E. Sources and Emissions of Polycyclic Organic Matter. U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina. EPA Report No. 450/5-83-010b.
pp. 5-58 to 5-62. 1983.
Siebert, P.C. et al. Preliminary Assessment of the Sources. Control and Population Exposure to
Airborne Polycyclic Organic Matter (POM) as Indicated by Benzo(a')pyrene fBaP).
U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Pollutant
Strategies Branch, Research Triangle Park, North Carolina. Prepared under EPA Contract
No. 68-02-2836. pp. 78-79. 1978.
Telephone Conversation between P. Mulrine, U.S. Environmental Protection Agency, and P.
Keller, Radian Corporation. "Preliminary Data from Integrated Iron and Steel MACT
Development Program." June 22, 1994.
U.S. Environmental Protection Agency. Compilation of Air Pollutant Emissions Factors.
Volume I: Stationary Point and Area Sources. AP-42, Fifth Edition, Section 7.5.
U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Research
Triangle Park, North Carolina, p. 7.5-1. 1995.
U.S. Environmental Protection Agency. Survey of Cadmium Emission Sources. EPA Report
No. 450/3-81-013. Office of Air Quality Planning and Standards, Research Triangle Park, North
Carolina. 1981.
U.S. Environmental Protection Agency. An Investigation of the Best Systems of Emission
Reduction for Sinter Plants in the Iron and Steel Industry. U.S. Environmental Protection
Agency, Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina.
Preliminary Report. 1977.
4-230
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4.4.3 Ferroalloy Manufacturing
Process Description
Ferroalloys are crude alloys of iron and one or more other elements that are used
for deoxidizing molten steels and making alloy steels. The major types of ferroalloys produced
are (Houck, 1993):
Ferroaluminum Ferrosilicon
Ferroboron Ferrotitanium
Ferrocolumbium Ferrovanadium
Ferrochromium Ferrotungsten
Ferrochromium-silicon Ferrozirconium
Ferromanganese Manganese metal
Ferromolybdenum Nickelcolumbium
Ferronickel Silicon metal
Ferrophosphorus Silicomanganese
Ferroalloys can be produced by five different processes; the primary method uses
electric arc furnaces (EAFs). Ferroalloy manufacturing is a potential source of emissions of
POM compounds because coke or coal is charged to the high-temperature smelting furnaces used
in the ferroalloy industry and burned. Because combustion efficiency in the furnace environment
is low, unburned hydrocarbons, including PAHs, are formed and emitted with the furnace
exhaust. However, ferroalloy production processes other than EAFs have not been identified as
POM emission sources (Kelly, 1983).
The EAF method of ferroalloy production is depicted in Figure 4.4.3-1
(U.S. EPA, 1980; U.S. EPA, 1974). Metal ores and other necessary raw materials such as quartz
or quartzite (slagging materials), alumina (a reducing agent), limestone, coke or coal, and steel
scrap are brought to ferroalloy facilities by ship, truck, or rail and stored on site. Depending on
its moisture content and physical configuration, metal ore may need to be dried and/or sintered
4-231
-------
DRYING AND SINTER-
ING PRETREATMENT
j
I
i
POM EMISSIONS
I
METALS ORES ™KC A»D ^ ^™.™
^ SIZING
1
N> COKE, COAL,
Si ALUMINA, — "~
QUARTZ RAW
MATERIALS
...........^.Indicates potential ferroalloy
process operations.
ARC FURNACE
FERROALLOY
CASTING
RECYCLED J SLAG
SLAG
CONCENTRATION
1
SLAG TO LANDFILL
FINAL
FERROALLOY -,
PRODUCT
^
FERROALLOY
REMOVAL ANE
GRADING
}
FERROALLOY
CRUSHING
t
FERROALLOY
SCREENING
1
FERROALLOY
PACKAGING
Figure 4.4.3-1. Typical Electric Arc Furnace Ferroalloy Manufacturing Process
Source: U.S. EPA, 1980
-------
prior to being crushed, sized, and mixed with other process raw materials. After the proper
charge mixture has been prepared, the charge is weighed and fed to a submerged EAF for
smelting.
Three types of EAFs can be used for ferroalloy production: open, semi-covered,
and covered (sealed). They may be charged continuously or intermittently. EAFs contain three
carbon electrodes, which are vertically suspended above the furnace hearth and extend 3 to 5 feet
(1 to 1.5m) into the charge materials. Three-phase current arcs through the charge materials
from electrode to electrode, and the charge is smelted as electrical energy is converted to heat.
The intense heat around the electrodes (4,000 to 5,000°F [2,204 to 2,760°C]) results in carbon
reduction of the metal (e.g., chrome, manganese) and iron oxides in the charge and the formation
of the particular ferroalloy. EAF capacities range from 0.25 to 65 tons (0.23 to 59 Mg). Melting
capacities range up to 10 Mg (11 tons) per hour (Barnard, 1990). Nine to 11 pounds of carbon
electrode are consumed per ton of metal melted (U.S. EPA, 1990).
The molten ferroalloy is periodically tapped into ladles from tapholes in the lower
furnace wall, cast into molds, and allowed to cool and solidify. The casts are then removed from
the molds and graded and broken. The broken ferroalloy is passed through a crusher and
screened. The ferroalloy product is then stored, packaged, and shipped to the consumer.
Impurities from the smelting process are trapped in a slag that forms inside the
EAF. The slag is periodically tapped and treated by a concentration process to recovery metal
values. Slag is processed in a flotation system, where metal particles sink to the bottom while
the slag floats. The recovered metals are recycled to the furnace and the remaining slag is
removed and disposed of.
Open EAF—Of the three types of EAFs that may be used to produce ferroalloys, open furnaces
are the most common type and also have the highest potential for particulate emissions
(U.S. EPA, 1974). An open EAF is pictured in Figure 4.4.3-2. A hood is usually located 6 to
8 feet (1.8 to 2.4 m) above the furnace crucible rim. Dust and fumes from the smelting process
4-233
-------
U)
ELECTRODES
EXTENDING
THROUGH
HOOD
MIX FEED
CHUTE
(TYPICAL)
I—I—I—I—I I I I ' '
POTENTIAL _
FUGITIVE POM
EMISSIONS
POM EMISSIONS
O
0.
O
u.
tu
Figure 4.4.3-2. Open Electric Arc Furnace
-------
are drawn into the hood along with large volumes of ambient air. Advantages of the open
furnace include the ability to stoke it during operation and the flexibility to manufacture several
types of ferroalloy without altering the furnace design.
Semi-covered EAF--A semi-covered EAF is pictured in Figure 4.4.3-3. A cover seals the top of
the furnace except for openings around the electrodes through which raw material is charged.
These furnaces are either hooded or maintained under negative pressure to collect emissions from
around the electrodes. Because semi-overed furnaces cannot be stoked, crusting and bridging of
ferroalloys around the electrodes and charge holes may prevent uniform descent of the charge
into the furnace and blows (jets of extremely hot gases originating in the high-temperature zone
near the electrode tips) may emerge around the electrodes at high velocity (U.S. EPA, 1980;
U.S. EPA, 1974; U.S. EPA, 1984).
Sealed EAF—The third type of EAF, the closed or sealed furnace, is illustrated in Figure 4.4.3-4.
Packing is used to seal the cover around the electrodes and charging chutes. The furnace is not
stoked, and a slight positive pressure is maintained to prevent leakage of the air into the furnace.
Care must also be taken to prevent water leaks, which could cause an explosive gas release that
could damage the furnace and threaten worker safety. Sealed furnace designs are specifically
used in the manufacture of narrow families of ferroalloys, so plants using sealed furnaces have
less flexibility to produce different types of ferroalloys.
Emissions Control Techniques—All types of EAFs produce emissions consisting of a variety of
compounds, including POM, in both gaseous and paniculate forms. Baghouses were used to
control emissions from 87 percent of the open ferroalloy furnaces operating in 1980. Testing of
these control systems indicates total PM removal efficiency of over 99 percent. Such systems are
also effective in controlling POM compounds adsorbed onto PM10 emissions. Testing conducted
on baghouses controlling open furnace emissions indicates organic matter control efficiencies
from 25 to 65 percent, with benzo(a)pyrene (BaP) control efficiencies of 61 to 74 percent.
Higher organic matter control efficiencies were achieved by baghouses controlling open furnace
emissions than by those controlling secondary fume emissions from semi-covered EAFs
(Westbrook, 1983).
4-235
-------
POM EMISSIONS
4*-
0\
MIX CHUTE
(TYPICAL)
?OM EMISSION$
Figure 4.4.3-3. Semi-covered Electric Arc Furnace
Source: U.S. EPA, 1974
-------
ELECTRODES
N)
MIX FEED
(TYPICAL)
COVER
ELECTRODE
SEAL
POM EMISSIONS
UJ
Figure 4.3.3-4. Covered (Sealed) Electric Arc Furnce
Source: U.S. EPA, 1974
-------
High-pressure-drop venturi scrubbers and ESPs have also been applied to open
ferroalloy EAFs. Reported total PM collection efficiencies for scrubbers ranged from 94 to
98 percent. When ESPs were used, the gas was conditioned with ammonia to enhance
paniculate resistivity and increase collection efficiency. Estimated total PM removal efficiencies
for the ESPs were 98 percent (Kelly, 1983; U.S. EPA, 1980; U.S. EPA, 1974; U.S. EPA, 1984).
Uncontrolled organic matter generation rates of open EAFs are generally lower
than those of covered furnaces on a throughput basis because of more complete combustion of
gases. However, organic matter emissions to the atmosphere may be as high or higher from an
open furnace controlled by a baghouse than from a sealed furnace producing an equivalent
product controlled by a scrubber (Westbrook, 1983).
In the case of semi-covered furnaces, offgases are drawn from beneath the furnace
cover through ducts leading to a control device. However, fugitive particulates and fumes escape
through the openings around the electrodes. Generally, hoods are in place above the furnaces to
capture these emissions along with tapping fumes and route them to a secondary fume control
device such as a baghouse. One test report indicated a control efficiency for organic matter for a
semi-covered furnace secondary fume baghouse of 13 percent (Westbrook, 1983). Wet
scrubbers, including both multistage centrifugal scrubbers and venturi scrubbers, are also used on
semi-covered ferroalloy furnaces. Up to 99 percent total PM removal efficiency has been
reported for centrifugal scrubbers. Venturi units can exhibit even greater PM efficiencies.
Reported control efficiencies for organic matter from scrubber-controlled semi-covered EAFs
range from 64 to 88 percent, with BaP control efficiencies reported at greater than 99 percent
(Westbrook, 1983).
Venturi scrubbers are commonly used to control emissions from sealed ferroalloy
EAFs; however, a few installations use baghouses. In general, total uncontrolled emissions
vented to a control device from a sealed furnace are lower than emissions from other ferroalloy
EAFs because no air enters sealed furnaces. Resultant gas flows (volumes) to the control device
are only 2 to 5 percent of those from open furnaces (U.S. EPA, 1980). However, uncontrolled
organic matter in sealed and semi-covered EAFs with minimal undercover combustion may be
4-238
-------
significantly higher than generation in semi-covered EAFs with undercover combustion or open
furnaces (Westbrook, 1983).
Emission Factors
PAH emission factor data were identified for open, semi-covered, and sealed
ferroalloy manufacturing EAFs in two test reports (U.S. EPA, 1980; Westbrook, 1983).
Emission factors are presented in Tables 4.4.3-1 to 4.4.3-4. All emission factor units are in
Ib/MMBtu (g/MW-h) of energy consumed by the furnace. The average amount of energy
consumed in EAF operation per unit output is approximately 21.85 MMBtu/ton
(7.05 MW-hr/Mg) of alloy produced (Chin Telecon, 1994).
PAH emission factors for open EAFs producing silicon metal are listed in
Table 4.4.3-1. The emission factors are based on test data from a single EAF with a rated power
capacity of 58 MMBtu/hr (17 MW). Furnace emissions were controlled by a baghouse and
sampling for PAHs was conducted at the outlet of the baghouse. BaP emissions were quantified
both before and after the baghouse (uncontrolled and controlled). The baghouse control
efficiency for BaP was estimated at 61.1 percent. Sampling and analytical methods were used to
quantify both particulate and vapor phase PAHs (Westbrook, 1983).
PAH emission factors for semi-covered EAFs producing 50 percent ferrosilicon
are presented in Table 4.4.3-2. The emission factors are based on test data from two wet
scrubber controlled EAFs. Both test programs utilized sampling and analytical methods capable
of quantifying both particulate and vapor phase POM. Westbrook (1983) measured pre-scrubber
(uncontrolled) BaP emissions from a 147 MMBtu/hr (43 MW) EAF of 2.62E-13 Ib/MMBtu
(4.06 g/MW-h). Controlled BaP emissions from the same unit were estimated at
1.55E-5 Ib/MMBtu (0.024 g/MW-h), assuming the scrubber flare was not operating and
73.6 percent capture of BaP in the secondary fume baghouse. Scrubber controlled BaP emissions
reported by EPA (1980) for a 57 MMBtu/hr (16.8 MW) EAF producing 50 percent ferrosilicon
were substantially higher, at 6.46E-4 Ib/MMBtu (1.0 g/MW-h). All additional PAH emission
4-239
-------
factors reported in Table 4.4.3-2 represent scrubber controlled emissions as reported by EPA
(1980). Total POM emissions were estimated to be 0.088 Ib/MMBtu (137 g/MW-h).
PAH emission factors for covered EAFs are presented in Tables 4.4.3-3 and
4.4.3-4. The emission factors are based on test data from a single furnace operating under two
different ferroalloy and control scenarios. Both particulate and vapor phase PAHs were
quantified in the test program (U.S. EPA, 1980).
The emission factors in Table 4.4.3-3 represent uncontrolled PAH emissions from
the closed EAF during the production of ferromanganese. Sampling during this furnace
operating scenario was conducted prior to the wet scrubber and flare control system. The furnace
operating power during testing was 59.1 MMBtu/hr (17.3 MW). Total uncontrolled POM
emissions were estimated to be 0.101 Ib/MMBtu (156 g/MW-h).
The emission factors in Table 4.4.3-4 represent scrubber controlled emissions
from the same closed EAF during the production of silicomanganese. During this test series,
samples were taken after the high-pressure-drop wet scrubber and prior to the flare. The furnace
operating power during testing under silicomanganese production was 76.8 MMBtu/hr
(22.5 MW). Controlled total POM emissions were estimated to be 6.46 E-4 Ib/MMBtu
(1.0 g/MW-h) (U.S. EPA, 1980).
Source Locations
The latest information published by the U.S. Bureau of Mines on the locations of
ferroalloy manufacturing facilities in the United States is listed in Table 4.4.3-5. According to
these data, as of 1992,27 companies operated a total of 34 ferroalloy facilities in the United
States. Ohio and Pennsylvania contained the greatest number of ferroalloy production facilities,
with five and six facilities, respectively. Ohio, Pennsylvania, New York, and Alabama together
contained approximately 50 percent of the total number of facilities nationwide (Houck, 1993).
4-240
-------
TABLE 4.4.3-1. PAH EMISSION FACTORS FOR OPEN ELECTRIC ARC FURNACES PRODUCING SILICON METAL
Control
SCC Number Emission Source Device Pollutant
3-03-006-04 Electric Arc Furnace None Ben? >(a)pyrene
3-03-006-04 Electric Arc Furnace Baghouse Benz(a)anthraeene
Ben?o(a)pyrene
Chrysene
Anthracene
Fluoranthene
Fluoi one
Naphthalene
Pyrene
Meth y 1 anthrac cnes
Phenv (naphthalene
Average Emission
Factor in Ib/MMBtu
(g/MW-h)a
1.36E-05
(0.021)
7.42E-05
(0.115)
5.17E-06
(8.00E-03)
2.60E-04
(0.402)
4.19E-03
(6.49)
1.60E-03
(2.47)
3.45E-04
(0.534)
2.33E-02
(36.1)
8.91E-04
(1.38)
1.22E-03
(1.90)
l.OOE-03
(1.55)
Emission Emission
Factor Factor
Range Rating
E
E
ND-1.55E-4 E
(ND - 0.240)
E
E
E
E
E
E
E
E
"Emission factors arc in Ib (g) of pollutant emitted per MMBtu (kw-h).
Source: Westbrook, 1983.
-------
TABLE 4.4.3-2. PAH EMISSION FACTORS FOR SEMI-COVERED ELECTRIC ARC FURNACES
PRODUCING 50 PERCENT FERROSILICON
Emission Control
SCC Number Source Device Pollutant
3-04-006-01 Electric Arc None Benzo(a)pyrene
Furnace
3-04-006-01 Electric Arc Wet Benz(a)anthracene
Furnace Scrubber
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Indeno( 1 ,2,3-cd)pyrene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Phenanthrene
Average Emission
Factor in Ib/MMBtu
(g/MW-h)a
2.62E-03
(4.06)
4.13E-03
(6.40)
3.31E-04
(0.512)
1.36E-03
(2.10)
6.46E-05
(0.100)
3.16E-03
(4.90)
4.33E-04
(0.670)
7.23E-03
(11.2)
1.23E-03
(1-90)
1.08E-02
(16.7)
2.96E-02
(45.9)
7.23E-03
(11.2)
Emission Factor Emission
Range in Ib/MMBtu Factor
(g/MW-h)a Rating
E
E
1.55E-05-6.46E-04 E
(0.024- 1.00)
E
E
E
E
E
E
E
E
E
Reference
Westbrook, 1983
U.S. EPA, 1980
Westbrook, 1983;
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
(continued)
-------
TABLE 4.4.3-2. (Continued)
Ni
Emission Control
SCC Number Source Device Pollutant
3-04-006-01 Electric Arc Wet Pyrene
(continued) Furnace Scrubber
(continued) (continued)
Anthanthrene
Benzo(a) and
Ben/o(b)fluorene
Ben?o(e)pyrene
Benzo(ghi)fluoranthene
Coronene
Cyclopenta(def)-
phenanthrene
Methylanthracenes
Methyipyrenc
Perylene
Average Emission
Factor in Ib/MMBtu
(g/MW-h)a
1.12E-02
(17.4)
3.29E-04
(0.510)
4.84E-04
(0.750)
3.16E-04
(0.490)
3.49E-03
(5.40)
3.94E-04
(0.610)
4.20E-03
(6.50)
5.94E-04
(0.920)
2.58E-05
(0.0400)
1 .68E-04
(0.260)
Emission Factor Emission
Range in Ib/MMBtu Factor
(g/MW-h)a Rating
E
E
E
E
E
E
E
E
E
E
Reference
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
U.S. EPA, 1980
aEmission factors are in Ib (g) of pollutant emitted per MMBtu (MW-h).
-------
TABLE 4.4.3-3. PAH EMISSION FACTORS FOR COVERED ELECTRIC ARC FURNACES
PRODUCING FERROMANGANESE
SCC Number Emission Source Control Device Pollutant
3-03-006-51 Electric Arc Furnace None Chrysene
I )ibenz(a,h)anthracene
Indeno(l ,2,3-cd)pyrene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Pyrene
Benzo(e)pyrene
Carbazole
Coronenc
Methylanthracenes
Average Emission
Factor in Ib/MMBtu
(g/MW-h)a
7.75E-03
(12.0)
1.42E-04
(0.220)
9.69E-04
(1.50)
3.54E-02
(54.9)
2.26E-04
(0.350)
3.54E-02
(54.9)
2.58E-03
(4.00)
3.68E-04
(0.570)
8.39E-03
(13.0)
1.55E-03
(2.40)
8.39E-05
(0.130)
3.67E-03
(6.00)
Emission
Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.4.3-3. (Continued)
SCC Number Emission Source Control Device Pollutant
3-03-006-5 1 Electric Arc Furnace None Methylchi ysenes
(continued) (continued)
Methylpyiene
Perylene
7 , 1 2-Dimethylbenz(a)anthracene
Methylbenzopyrenes
3-MethyIchIolanthrene
Dibenzo(c,g)carbazole
Dibenzo(ai+ah)pyrenes
Average Emission
Factor in Ib/MMBtu
(g/MW-h)a
8.39E-04
(1.30)
2.26E-03
(3.50)
4.97E-04
(0.770)
9.04E-05
(0.140)
1.94E-04
(0.300)
6.46E-05
(0.100)
1.29E-05
(0.0200)
8.39E-05
(0.130)
Emission
Factor
Rating
E
E
E
E
E
E
E
E
"Emission factors are in Ib (g) of pollutant emitted per MMBtu (MW-h).
Source: U.S. EPA, 1980.
-------
TABLE 4.4.3-4. PAH EMISSION FACTORS FOR COVERED ELECTRIC ARC FURNACES
PRODUCING SILICOMANGANESE
£
ON
Control
SCC Number Emission Source Device Pollutant
3-03-006-54 Electric Arc Furnace Wet Scrubber Chrysene
Anthracene
Fluoranthene
Fluorene
Pyrene
Methylanthracenes
Methylpyrene
Average Emission
Factor in Ib/MMBtu
(g/MW-h)a
2.62E-06
(3.90)
3.29E-04
(0.510)
3.47E-05
(0.0580)
2.32E-04
(0.360)
3.42E-05
(0.0530)
1.10E-05
(0.0170)
7.75E-07
(1.20E-03)
Emission
Factor
Rating
E
E
E
E
E
E
E
"Emission factors are in Ib (g) of pollutant emilied per MMBtu (MW-h).
Source: U.S. EPA, 1980.
-------
TABLE 4.4.3-5. LOCATIONS OF FERROALLOY PRODUCERS
IN THE UNITED STATES IN 1992
Producer
Ferroalloys
AMAX Inc., Climax Molybdenum
Company Division
America Alloys, Inc.
Applied Industrial Minerals
Corporation (AIMCOR)
Bear Metallurgical, Inc.
Cabot Corporation
Cyprus Minerals Company
Dow Corning Corporation
Elkem A/S, Elkem Metals Company
Gait Alloys, Inc.
Glenbrook Nickel Company
Globe Metallurgical, Inc.
HTP Company
Keokuk Ferro-Sil, Inc.
Kerr-McGee Chemical Corporation
Macalloy, Inc.
Metallurg, Inc., Shieldalloy
Metallurgical Corporation
Reading Alloys, Inc.
Satra Concentrates, Inc.
Silicon Metaltech, Inc.
Plant Location
Langeloth, PA
New Haven, WV
Bridgeport, AL
Butler, PA
Revere, PA
Greenvalley, AZ
Springfield, OR
Alloy, WV
Ashtabula, OH
Marietta, OH
Niagara Falls, NY
Canton, OH
Riddle, OR
Beverly, OH
Selma, AL
Sharon, PA
Keokuk, IA
Hamilton, MS
Charleston, SC
Cambridge, OH
Newfield, NJ
Robesonia, PA
Steubenville, OH
Wenatchee, WA
Type of Furnace
Metallothermic
Electric Arc
Electric Arc
Metallothermic
Metallothermic
Metallothermic
Electric Arc
Electric Arc and
Electrolytic
Electric Arc
Electric Arc
Electric Arc
Metallothermic
Electric Arc
Electrolytic
Electric Arc
Electric Arc
Metallothermic
Metallothermic
Slag conversion
Electric Arc
4-247
(continued)
-------
TABLE 4.4.3-5. (Continued)
Producer
Plant Location
Type of Furnace
Simetco
SKW Alloys, Inc.
Strategic Minerals Corporation
(STRATCOR)
Teledyne, Inc., Teledyne Wan
Chang, Albany Division
Union Oil Company of California,
Molycorp, Inc.
Montgomery, AL
Calvert City, KY
Niagara Falls, NY
Niagara Falls, NY
Albany, OR
Washington, PA
Electric Arc
Electric Arc
Electric Arc
Metallothermic
Electric Arc and
Metallothermic
Ferrophosphorus
FMC Corporation, Industrial
Chemical Division
Monsanto Company, Monsanto
Industrial Chemicals Company
Pocatello, ID
Columbia, TN
Soda Springs, ID
Occidental Petroleum Corporation Columbia, TN
Electric Arc and
metallothermic
Electric Arc and
metallothermic
Electric Arc and
metallothermic
NOTE: This list is subject to change as market conditions change, facility ownership changes, plants are closed
down, etc. The reader should verify the existence of specific facilities by consulting current lists and/or
the plants themselves. The level of PAH emissions from any given facility is a function of variables such
as capacity, throughput, and control measures, and should be determined through direct contacts with
plant personnel.
Source: Houck, 1993.
4-248
-------
SECTION 4.4.3 REFERENCES
Barnard, W.R. Emission Factors for Iron and Steel Sources - Criteria and Toxic Pollutants. U.S.
Environmental Protection Agency, Control Technology Center, Office of Research and
Development, Washington, DC. EPA-600/2-90-024. p. 6. 1990.
Houck, G.W. "Iron and Steel." In: Minerals Yearbook. 1992. U.S. Bureau of Mines,
Washington, DC. p. 21. 1993.
Kelly, M.E. Sources and Emissions of Polvcvclic Organic Matter. U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina. EPA Report No. 450/5-83-01 Ob.
pp. 5-58 to 5-62. 1983.
Telephone conversation between Conrad Chin (U.S. Environmental Protection Agency) and
Eric Goehl (Radian). U.S. Environmental Protection Agency MACT Background Information:
U.S. Ferroalloy Production Levels - 1991. October 31, 1994.
U.S. Environmental Protection Agency. Emission Factors for Iron Foundries - Criteria and Toxic
Pollutants. Control Technology Center, Office of Research and Development, Cincinnati, Ohio.
EPA-600/2-90-044. p. A-72. 1990.
U.S. Environmental Protection Agency. Locating and Estimating Air Emissions from Sources of
Chromium. Office of Air Quality Planning and Standards, Research Triangle Park, North
Carolina. EPA Report No. 450/4-84-007g. 1984.
U.S. Environmental Protection Agency. A Review of Standards of Performance for New
Stationary Sources - Ferroalloy Production Facilities. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. EPA Report No. 450/3-80-041. pp. 1-66.
1980.
U.S. Environmental Protection Agency. Background Information for Standards of Performance:
Electric Submerged Arc Furnaces for Production of Ferroalloys. Volume I: Proposed Standards.
Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina. EPA
Report No. 450/2-74-018a. 1974.
Westbrook, C.W. Multimedia Environmental Assessment of Electric Submerged Arc Furnaces
Producing Ferroalloys. U.S. Environmental Protection Agency, Industrial Environmental
Research Laboratory, Research Triangle Park, North Carolina. EPA-600/2-83-092. pp. 17-29,
48-49. 1983.
4-249
-------
4.4.4 Iron and Steel Foundries
Process Description
Iron and steel foundries can be defined as those that produce gray, white, ductile, or
malleable iron and steel castings. Both cast irons and steels are solid solutions of iron, carbon,
and various alloying materials. Although there arc many types of each, the iron and steel families
can be distinguished by their carbon content. Cast irons typically contain 2 percent carbon or
greater; cast steels usually contain less than 2 percent carbon (U.S. EPA, 1980).
Iron castings are used in almost all types of equipment, including motor vehicles, farm
machinery, construction machinery, petroleum industry equipment, electrical motors, and iron
and steel industry equipment.
Steel castings are used in motor vehicles, railroad equipment, construction machinery,
aircraft, agricultural equipment, ore refining machinery, and chemical manufacturing equipment
(U.S. EPA, 1980). Steel castings are classified on the basis of their composition and heat
treatment, which determine their end use. Classifications include carbon, low-alloy, general-
purpose-structural, heat-resistant, corrosion-resistant, and wear-resistant.
The following four basic operations are performed in all iron and steel foundries:
• Storage and handling of raw materials;
• Melting of the raw materials;
• Transfer of the hot molten metal into molds; and
• Preparation of the molds to hold the molten metal.
4-250
-------
Other processes present in most, but not all, foundries include:
• Sand preparation and handling;
• Mold cooling and shakeout;
• Casting cleaning, heat treating, and finishing;
• Coremaking; and
• Pattern making.
A generic process flow diagram for iron and steel foundries is shown in Figure 4.4.4-1.
Figure 4.4.4-2 depicts the emission points in a typical iron foundry (U.S. EPA, 1995).
Iron and steel castings are produced in a foundry by injecting or pouring molten metal
into cavities of a mold made of sand, metal, or ceramic material. Input metal is melted by the use
of a cupola (a cylindrical shell with either a refractory-lined or water-cooled inner wall), an
electric arc furnace (EAF), or an induction furnace. About 70 percent of all iron castings are
produced using cupolas, with lesser amounts produced in EAFs and induction furnaces.
However, the use of EAFs in iron foundries is increasing. Steel foundries rely almost exclusively
on EAFs or induction furnaces for melting purposes.
In either type of foundry, when the poured metal has solidified, the molds are separated
and the castings removed from the mold flasks on a casting shakeout unit. Abrasive
(shotblasting) cleaning, grinding, and heat treating are performed as necessary. The castings are
then inspected and shipped to another industry for machining and/or assembly into a final
product (U.S. EPA, 1980).
In a typical foundry operation, charges to the melting unit are sorted by size and density
and cleaned (as required) prior to being put into the melter. Charges consist of scrap metal,
ingot, carbon (coke), and flux. Prepared charge materials are placed in crane buckets, weighed,
4-251
-------
to
Return Sand
Transfer.
Processing and
Storage
Scrap Metal
and Ingot
(Also Fuel
and Flux)
Finished Casting
(Product)
Figure 4.4.4-1. Process Flow Diagram for a Typical Sand-cast Iron and Steel Foundry
Source: U.S. EPA, 1980.
-------
Fugitive
Particulates
Fugitive
Oust
Raw Materials,
Unloading, Storage,
Transfer
• Flux
• Metals
• Carbon Sources
• Sand
• Binder
Fumes and
Fugitive Dust
Fugitive
Dust
Sand
Scrap
Preparation
Furnace
' Cupola
1 Electric Arc
> Induction
• Other
Tapping,
Treating
Mold Pouring,
Cooling
Casting
Shakeout
Hydrocarbons,
CO, and Smoke
Furnace
Vent
Fugitive
Dust
Fugitive
Fumes and
Dust
Fugitive
Fumes and
Dust
Fumes and
Fugitive
Dust
Cooling
Cleaning, Rnishing
Fumes and
Fugitive
Dust
Fugitive
Dust
Shipping
Figure 4.4.4-2. Emission Points in a Typical Iron and Steel Foundry
Source: U.S. EPA, 1995.
4-253
-------
and transferred into the melting furnace or cupola. The charge in a furnace or cupola is heated
until it reaches a certain temperature and the desired product chemistry of the melt has been
attained. After the desired product is obtained, the molten metal is either poured out of the
furnace into various-size teeming ladles and then into the molds or it is transferred to holding
furnaces for later use.
Five foundry processes (metal melting, mold and core production, inoculation, pouring,
and greensand shakeout [the removal of castings from a sand mold]) have been identified as
potential sources of POM emissions. The most significant source of aromatic hydrocarbon
emissions is metal melting, followed by pouring and greensand shakeout (U.S. EPA, 1990).
Metal Melting Process—The metal melting process in iron and steel foundries is
accomplished primarily in cupolas, and to a lesser extent in EAFs. (See Section 4.4.3 for
available emission factors for EAFs producing ferroalloys.) Cupolas are charged with alternate
layers of coke, metallics, and fluxes. Combustion air is introduced into the cupola through
tuyeres located at the base. The heat produced by the burning coke melts the iron, which flows
down and is tapped from the bottom of the cupola. Fluxes combine with non-metallic impurities
in the charge and form slag, which is removed through tap holes at the bottom of the cupola.
Cupola capacities range from 1 to 30 tons (1 to 27 Mg) per hour, with a few large units capable
of producing close to 100 tons (90 Mg) per hour. Larger furnaces are operated continuously,
with periodic inspections and cleanings between burn cycles (U.S. EPA, 1990).
Mold and Core Production—The casting, or mold pouring and cooling operation, in iron
and steel foundries has been identified as a source of POM emissions. The origin of these POM
emissions is suspected to be the organic binders, including coal powder and coal tar pitch, used
to form the sand molds for molten metal casting. When the hot molten metal contacts the sand
mold, pyrolysis occurs and a plume of smoke is generated that contains a rich mixture of organic
compounds, including POM. In addition to casting, mold preparation and casting shakeout
(removal from the mold) activities have been determined to generate POM emissions.
Greensand shakeout releases products of thermal decomposition of the organic chemical binders
used in mold preparation.
4-254
-------
Emission Control Techniques—POM emissions from cupolas can vary widely,
depending on blast rate, blast temperature, melt rate, coke-to-melt ratio, and control technologies.
Control technologies commonly used to control emissions from iron and steel foundry metal
melting operations include baghouses, wet scrubbers, and afterburners. Additionally, POM
emissions due to coke combustion may be reduced by substitution of gas for heat or the use of
graphite as a carbon source (U.S. EPA, 1990).
Potential POM emissions from molding, casting, and shakeout appear to be a function
of the type and quantity of organic binder used to produce casting molds. Emissions of POM
from these foundry processes are fugitive in nature and likely exist in both particulate and
gaseous forms. Fugitive emissions from such sources are generally controlled with local hooding
or building ventilation systems that are ducted to a control device (predominantly baghouses) or
to the atmosphere (U.S. EPA, 1990; Verma et al., 1982; Schimberg, 1980; Quilliam et ah, 1985;
McCallaetah, 1985).
Emission Factors
Data from two testing programs at a single gray iron foundry producing centrifugally
cast iron pipe were averaged to develop PAH emission factors for iron foundry furnaces
(EMCON, 1990; Normandeau, 1993). Emission factor data were not available for steel
foundries. The emission factors for iron foundries are presented in Table 4.4.4-1. The emission
source tested was a cupola, charged in a batch mode with pig iron, scrap iron, steel, coke, and
limestone. Coke combined with combustion air provided the heat necessary to-meIt the metal,
which was continuously tapped from the cupola, converted to ductile iron, and poured into steel
pipe molds. Combustion gases from the cupola were vented to a gas-/oil-fired afterburner
followed by a baghouse. Between the two testing programs, the facility underwent process and
control device modifications to reduce emissions of toxic compounds. These modifications
included an upgrade of the existing baghouse and conversion of the oil-fired afterburners to gas.
The modifications resulted in a measurable reduction in PAH emissions.
4-255
-------
TABLE 4.4.4-1. PAH EMISSION FACTORS FOR IRON FOUNDRIES
a\
SCC Number Emission Source Control Device Pollutant
3-04-003-01 Cupola Furnace Afterburner/Baghouse Benz(a)anthraccne
Benzo(a)pyrenc
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Diben/.(a,h)anihracenc
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluorcne
Average Emission
Factor in Ib/ton
(kg/Mg)a
7.70E-06
(3.85E-06)
3.85E-07
(1.29E-07)
2.80E-06
(1.40E-06)
2.37E-06
(1.18E-06)
3.80E-06
(1.90E-06)
4.82E-07
(2.41E-07)
3.15E-06
(1.58E-06)
1.15E-07
(5.73E-08)
6.10E-08
(3.05E-08)
3.57E-07
(1.79E-07)
3.18E-06
(1.59E-06)
7.93E-08
(3.96E-08)
Emission Factor Range in
Ib/ton
(kg/Mg)a-b
3.01E-06-1.24E-05
(1.50E-06-6.19E-06)
1.50E-07-6.19E-07
(7.51E-08-3.10E-07)
1.10E-06-4.49E-06
(5.50E-07 - 2.25E-06)
9.42E-07 - 3.80E-06
(4.71E-07- 1.90E-06)
1.47E-06-6.12E-06
(7.36E-07 - 3.06E-06)
—
1.74E-08-2.12E-07
(8.68E-09- 1.06E-07)
4.91E-08 - 7.29E-08
(2.46E-08 - 3.64E-08)
1.38E-07-5.77E-07
(6.87E-08 - 2.88E-07)
1.10E-06-5.26E-06
(5.50E-07 - 2.63E-06)
7.60E-06-3.17E-05
(3.80E-06-1.58E-05)
...
Emission
Factor
Rating
D
D
D
D
D
E
D
D
D
D
D
E
(continued)
-------
TABLE 4.4.4-1. (Continued)
Average Emission
Factor in Ib/ton
SCC Number Emission Source Control Device Pollutant (kg/Mg)a
3-04-003-01 Cupola Furnace Afterburner/Baghouse Fluoranthene 1.96E-05
(9.82E-06)
Naphthalene 1.68E-07
(8.42E-08)
Phenanthrene 3.49E-06
(I.74E-06)
Pyrene 1 .44E-05
(7.18E-06)
Emission Factor Range in
Ib/ton
(kg/Mg)a-b
1.36E-06-5.62E-06
(6.79E-07-2.81E-06)
5.56E-06 - 2.32E-05
(2.78E-06-1.16E-05)
O.OOE+00 - O.OOE+00
(O.OOE+00 - O.OOE+00)
4.82E-07 - O.OOE+00
(2.4 1E-07- O.OOE+00)
Emission
Factor
Rating
D
D
D
D
'Emission factors are in Ib (Kg) of pollutant emitted per ton (Mg) of cast pipe pioduced.
bRanges represent averaged data from two test reports (single facility).
Source: EMCON, 1990; Normandeau, 1993.
fe
-4
-------
Source Locations
Based on a survey conducted by the EPA in support of the iron and steel foundry
Maximum Achievable Control Technology (MACT) standard development, there were 755 iron
and steel foundries in the United States in 1992 (Maysilles, 1993). Foundry locations can be
correlated with areas of heavy industry and manufacturing and, in general, with the iron and steel
production industry (Ohio, Pennsylvania, and Indiana). _,
Additional information on iron and steel foundries and their locations may be
obtained from the following trade associations:
• American Foundrymen's Society, Des Plaines, Illinois;
• National Foundry Association, Des Plaines, Dlinois;
• Ductile Iron Society, Mountainside, New Jersey;
• Iron Casting Society, Warrendale, Pennsylvania; and
• Steel Founders'Society of America, Des Plaines, Dlinois.
4-258
-------
SECTION 4.4.4 REFERENCES
EMCON Associates. Compliance Testing to Quantify Emissions at U.S. Pipe and Foundry
Company. Union City, California. December 1990.
Maysilles, J. H., "Foundry MACT Standards Update." Presented at the Sixth Annual American
Foundrymen's Society Environmental Affairs Conference. Milwaukee, Wisconsin.
August 22-24, 1993.
McCalla, D.R. et al. "Formation of BacteriaTTvIutagens from Various Mould Binder Systems
Used in Steel Foundries." In: Polynuclear Aromatic Hydrocarbons: Mechanisms. Methods, and
Metabolism. Proceedings of the Eighth International Symposium on Polynuclear Aromatic
Hydrocarbons. Columbus, Ohio, 1983. M. Cooke and A.J. Dennis, eds. Battelle Press,
Columbus, Ohio. pp. 871-884. 1985.
Normandeu Associates. Report to Emissions of Toxics Compounds from the Cupola Baghouse
at U.S. Pipe and Foundry Company. Union City, California. February 8-10, 1993.
Quilliam, M.A. et al. "Identification of Polycyclic Aromatic Compounds in Mutagenic
Emissions from Steel Casting." In: Biomedical Mass Spectrometry. 12(4): 143-150. 1985.
Schimberg, R.W. "Polycyclic Aromatic Hydrocarbons in Foundries." In: Journal of Toxicology
and Environment Health. 6(5-6): 1187-1194. September/November 1980.
U.S. Environmental Protection Agency. Compilation of Air Pollutant Emission Factors. AP-42,
Fifth Edition, Section 12.10: Gray Iron Foundries. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. 1995.
U.S. Environmental Protection Agency. Emissions Factors for Iron Foundries - Criteria and
Toxic Pollutants. Control Technology Center, Office of Research and Development, Cincinnati,
Ohio. EPA-600/2-90-044. 29pp. 1990.
U.S. Environmental Protection Agency. Electric Arc Furnaces in Ferrous Foundries -
Background Information for Proposed Standards. Office of Air Quality Planning and Standards.
U.S. Environmental Protection Agency, Research Triangle Park, North Carolina. EPA Report
No. 3-80-020a. May 1980.
Verma, D.K. et al. "Polycyclic Aromatic Hydrocarbons in Ontario Foundry Environments." In:
Annals of Occupational Hygiene. 25(l):17-25. 1982.
4-259
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4.4.5 Secondary Lead Smelting
Process Description
The secondary lead smelting industry produces elemental lead and lead alloys by
reclaiming lead, mainly from scrap automobile batteries. Blast, reverberatory, rotary, and electric
furnaces are used for smelting scrap lead and producing secondary lead. Smelting is the
reduction of lead compounds to elemental lead in a high-temperature furnace, which requires
higher temperatures (2,200 to 2,300°F [1,200 to 1,260°C]) than those required for melting
elemental lead (621 °F [327°C]). Secondary lead may be refined to produce soft lead (which is
nearly pure lead) or alloyed to produce hard lead. Most of the lead produced by secondary lead
smelters is hard lead that is used in the production of lead-acid batteries (U.S. EPA, 1994a).
Lead-acid batteries represent about 90 percent of the raw materials at a typical
secondary lead smelter, although this percentage may vary from one plant to the next. These
batteries contain approximately 18 Ib (8.2 kg) of lead per battery consisting of 40 percent lead
alloys and 60 percent lead oxide. Other types of lead-bearing raw materials recycled by
secondary lead smelters include drosses (lead-containing byproducts of lead refining), which may
be purchased from companies that perform lead alloying or refining but not smelting; battery
plant scrap, such as defective grids or paste; and scrap lead, such as old pipes or roof flashing.
Other scrap lead sources include cable sheathing, solder, and babbitt-metal (U.S. EPA, 1994a).
POM emissions from secondary lead smelters are expected to occur from the
combustion of the polymeric organic casings (plastic and rubber) on batteries (Bennet et al.,
1979, National Research Council, 1983).
As illustrated in Figure 4.4.5-1, the normal sequence of operations in a secondary
lead smelter is scrap receiving, charge preparation, furnace smelting, and lead refining and
alloying. In the majority of plants, scrap batteries are first sawed or broken open to remove the
lead alloy plates and lead oxide paste material. The removal of battery covers is typically
accomplished using an automatic battery feed conveyor system and a slow-speed saw. Hammer
4-260
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Batteries Arrlva
by Truck
Polypropylene
Plastic to
Recycling
Add to
Water Treatment
or Recycling
Other Lead-
Bearing Materials
and Scrap
•
i
Battery
Breaking
^
T
lnf Qrtd Metal.
Hard Rubber.
Separators
-
rials ^
Materials
Storage
[~~
1
1
1
i
i
i
i
!
OPTIONAL
1
1
Paste
Desulfurtzabon
Disposal
Finished
Product
Figure 4.4.5-1. Simplified Process Flow Diagram for Secondary Lead Smelting
Source: U.S. EPA, 1994a.
4-261
-------
mills or other crushing/shredding devices are then used to break open the battery cases.
Float/sink separation systems are typically used to separate plastic battery parts, lead terminals,
lead oxide paste, and rubber parts. The majority of lead smelters recover the crushed plastic
materials for recycling. Rubber casings are usually landfilled.
Paste desulfurization, an optional lead recovery step used by secondary lead
smelters, requires the separation of lead sulfate and lead oxide paste from the lead grid metal,
polypropylene plastic cases, separators, and hard rubber battery cases. Paste desulfurization
involves the chemical removal of sulfur from the lead battery paste. The process improves
furnace efficiency by reducing the need for fluxing agents to reduce lead-sulfur compounds to
lead metal. The process also reduces sulfur dioxide (SO2) furnace emissions. However, SO2
emissions reduction is usually a less important consideration because many plants that perform
paste desulfurization are also equipped with SO2 scrubbers. About one-half of smelters perform
paste desulfurization (U.S. EPA, 1994a).
After removing the lead components from the charge batteries, the lead scrap is
combined with other charge materials such as refining drosses, flue dust, furnace slag, coke.
limestone, sand, and scrap iron and fed to either a reverberatory, blast, rotary or electric smelting
furnace. Smelting furnaces are used to produce crude lead bullion, which is refined and/or
alloyed into final lead products. There are currently about 15 reverberatory furnaces, 24 blast
furnaces, 5 rotary furnaces, and 1 electric furnace operating in the secondary lead industry in the
United States (U.S. EPA, 1994a). Blast and reverberatory furnaces are currently the most
common types of smelting furnaces used in the industry, although some new plants are using
rotary furnaces.
Reverberatory Furnaces-A reverberatory furnace (Figure 4.4.5-2) is a rectangular refractory-
lined furnace. Reverberatory furnaces are operated on a continuous basis. Natural gas- or fuel
oil-fired jets located at one end, or at the sides, of the furnace are used to heat the furnace and
charge material to an operating temperature of about 2,000°F (1,100°C). Oxygen enrichment
may be used to decrease the combustion air requirements. Reverberatory furnaces are maintained
at negative pressure by an induced draft fan.
4-262
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Charge Chute
u>
Lead Well and Tap
Hydraulic Charge Ram
*,
1
Figure 4.4.5-2. Cross-Sectional View of a Typical Stationary Reverberatory Furnace
Source: U.S. EPA, 1994a.
-------
Reverberatory furnaces are used to produce a soft (nearly pure) lead product and a
lead-bearing slag. This is done by controlling the reducing conditions in the furnace so that lead
components are reduced to metallic lead bullion while the alloying elements (antimony, tin,
arsenic) in the battery grids, posts, straps, and connectors are oxidized and removed in the slag.
The reduction of PbSO4 and PbO is promoted by the carbon-containing coke added to the charge
material:
PbSO4 + C - Pb + CO2 + SO2
2PbO + C - 2Pb + CO2
The PbSO4 and PbO also react with the alloying elements to form lead bullion and
oxides of the alloying elements, which are removed in the slag.
The molten lead collects in a pool at the lowest part of the hearth. Slag collects in
a layer on top of this pool and retards further oxidation of the lead. The slag is made up of
molten fluxing agents such as iron, silica, and lime, and typically has significant quantities of
lead. Slag is usually tapped continuously and lead is tapped intermittently. The slag is tapped
into a crucible. The slag tap and crucible are hooded and vented to a control device.
Reverberatory furnace slag usually has a high lead content (as much as 70 percent by weight) and
is used as feed material in a blast or electric furnace to recover the lead content. Reverberatory
furnace slag may also be rerun through the reverberatory furnace during special slag campaigns
before being sent to a blast or electric furnace. Lead may be tapped into a crucible or directly
into a holding kettle. The lead tap is usually hooded and vented to a control device
(U.S. EPA, 1994a).
Blast Furnaces-A blast furnace (Figure 4.4.5-3) is a vertical furnace that consists of a crucible
with a vertical cylinder affixed to the top. The crucible is refractory-lined and the vertical
cylinder consists of a steel water-jacket. Oxygen-enriched combustion air is introduced into the
furnace through tuyeres located around the base of the cylinder.
4-264
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Charge Hopper
Exhaust Offtake to Afterburner
Charge
Coo! Water
Average Level of Charge
Lead Spout
Working Height
of Charge
2.4 to 3.0 m
Diameter at Tuyeres
— 68 to 120 cm
Figure 4.4.5-3. Cross-section of Typical Blast Furnace
Source: U.S. EPA, 1994a.
4-265
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Charge materials are pre-weighed to ensure the proper mixture and then
introduced into the top of the cylinder using a skip hoist, a conveyor, or a front-end loader. The
charge fills nearly the entire cylinder. Charge material is added periodically to keep the level of
the charge at a consistent working height while lead and slag are tapped from the crucible. Coke
is added to the charge as the primary fuel, although natural gas jets may be used to start the
combustion process. Combustion is self-sustaining as long as there is sufficient coke in the
charge material. Combustion occurs in the layer of the charge nearest the tuyeres.
At plants that operate only blast furnaces, the lead-bearing charge materials may
include broken battery components, drosses from the refining kettles, agglomerated flue dust, and
lead-bearing slag. A typical charge over one hour may include 4.8 tons (4.4 Mg) of grids and
paste, 0.3 tons (0.3 Mg) of coke, 0.1 tons (0.1 Mg) of calcium carbonate, 0.07 tons (0.06 Mg) of
silica, 0.5 tons (0.4 Mg) of cast iron, and 0.2 tons (0.2 Mg) of rerun blast furnace slag, to produce
3.7 tons (3.4 Mg) of lead. At plants that also have a reverberatory furnace, the charge materials
will also include lead-bearing reverberatory furnace slag (U.S. EPA, 1994a).
Blast furnaces are designed and operated to produce a hard (high alloy content)
lead product by achieving more reducing furnace conditions than those typically found in a
reverberatory furnace. Fluxing agents include iron, soda ash, limestone, and silica (sand). The
oxidation of the iron, limestone, and silica promotes the reduction of lead compounds and
prevents oxidation of the lead and other metals. The soda ash enhances the reaction of PbSO4
and PbO with carbon from the coke to reduce these compounds to lead metal.
Lead tapped from a blast furnace has a higher content of alloying metals (up to
25 percent) than lead produced by a reverberatory furnace. In addition, much less of the lead and
alloying metals are oxidized and removed in the slag, so the slag has a low metal content (e.g.,
1 to 3 percent) and frequently qualifies as a nonhazardous solid waste.
Because air is introduced into the blast furnace at the tuyeres, blast furnaces are
operated at positive pressure. The operating temperature at the combustion layer of the charge is
4-266
-------
between 2,200 and 2,600°F (1,200 and 1,400°C), but the temperature of the gases exiting the top
of the charge material is between 750 and 950°F (400 and 500°C).
Molten lead collects in the crucible beneath a layer of molten slag. As in a
reverberatory furnace, the slag inhibits the further oxidation of the molten metal. Lead is tapped
continuously and slag is tapped intermittently, slightly before it reaches the level of the tuyeres.
If the tuyeres become blocked with slag, they are manually or automatically "punched" to clear
the slag. A sight glass on the tuyeres allows the furnace operator to monitor the slag level and
ensure that the tuyeres are clear of slag. At most facilities, the slag tap is temporarily sealed with
a clay plug, which is driven out to begin the flow of slag from the tap into a crucible. The slag
tap and crucible are enclosed in a hood, which is vented to a control device.
A weir dam and siphon in the furnace are used to remove the lead from beneath
the slag layer. Lead is tapped from a blast furnace into either a crucible or directly to a refining
kettle designated as a holding kettle. The lead in the holding kettle is kept molten before being
pumped to a refining kettle for refining and alloying. The lead tap on a blast furnace is hooded
and vented to a control device.
Rotary Furnaces—As noted above, rotary furnaces (sometimes referred to as rotary reverberatory
furnaces) (Figure 4.4.5-4) are used at only a few recently constructed secondary lead smelters in
the United States (U.S. EPA, 1994a). Rotary furnaces have two advantages over other furnace
types: the ease of adjusting the relative amount of fluxing agents (because the furnaces are
operated on a batch rather than a continuous basis), and a better mix of the charge materials.
A rotary furnace consists of a refractory-lined steel drum mounted on rollers with
a variable-speed motor to rotate the drum. An oxygen-enriched natural gas or fuel oil jet at one
end of the furnace heats the charge material and the refractory lining of the drum. The
connection to the flue is located at the same end as the jet. A sliding door at the end of the
furnace opposite the jet allows charging of material to the furnace. Charge materials are typically
placed in the furnace using a retractable conveyor or charge bucket, although other methods are
possible.
4-267
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Hygiene Hood
Figure 4.4.5-4. Side View of a Typical Rotary Reverberatory Furnace
Source: U.S. EPA, 1994a.
4-268
-------
Lead-bearing raw materials charged to rotary furnaces include broken battery
components, flue dust, and drosses. Rotary furnaces can use the same lead-bearing raw materials
as reverberatory furnaces, but they produce slag that is relatively free of lead, less than 2 percent.
As a result, a blast furnace is not needed for recovering lead from the slag, which can be disposed
of as a nonhazardous waste.
Fluxing agents for rotary furnaces may include iron, silica, soda ash, limestone,
and coke. The fluxing agents are added to promote the conversion of lead compounds to lead
metal. Coke is used as a reducing agent rather than as a primary fuel. A typical charge may
consist of 12 tons (11 Mg) of wet battery scrap, 0.8 tons (0.7 Mg) of soda ash, 0.6 tons (0.5 Mg)
of coke, and 0.6 tons (0.5 Mg) of iron, and will yield approximately 9 tons (8 Mg) of lead
product (U.S. EPA, 1994a).
The lead produced by rotary furnaces is a semi-soft lead with an antimony content
somewhere between that of lead from reverberatory and blast furnaces. Lead and slag are tapped
from the furnace at the conclusion of the smelting cycle. Each batch takes 5 to 12 hours to
process, depending on the size of the furnace. Like reverberatory furnaces, rotary furnaces are
operated at a slight negative pressure.
Electric Furnaces—An electric furnace consists of a large, steel, kettle-shaped container that is
refractory-lined (Figure 4.4.5-5). A cathode extends downward into the container and an anode
is located in the bottom of the container. Second-run reverberatory furnace slag is charged into
the top of the furnace. Lead and slag are tapped from the bottom and side of the furnace,
respectively. A fume hood covering the top of the furnace is vented to a control device.
In an electric furnace, electric current flows from the cathode to the anode through
the scrap charge. The electrical resistance of the charge causes the charge to heat up and become
molten. There is no combustion process involved in an electric furnace.
4-269
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Electrode
Flue
Beth Level
-p.
o
Slag Tap
Electrode
Figure 4.4.5-5. Cross-Sectional View of an Electric Furnace for Processing Slag.
Source: U.S. EPA, 1994a.
-------
There is only one known electric furnace in operation in the U.S. for the
secondary lead industry. It is used to process second-run reverberatory furnace slag, and it
fulfills the same role as a blast furnace used in conjunction with a reverberatory furnace.
However, the electric furnace has two advantages over a blast furnace. First, because there are
no combustion gases, ventilation requirements are much lower than for blast or reverberatory
furnaces, and the potential for POM formation and emissions is greatly reduced. Second, the
electric furnace is extremely reducing, and produces a glass-like, nearly lead-free slag that is
nonhazardous (U.S. EPA, 1994a).
Refining, the final step in secondary lead production, consists of removing
impurities and adding alloying metals to the molten lead obtained from the smelting furnaces to
meet a customer's specifications. Refining kettles are used for the purifying and alloying of
molten lead.
Emission Control Techniques-Controls used to reduce organic emissions from smelting furnaces
in the secondary lead smelting industry include afterburners on blast furnaces and combined blast
and reverberatory exhausts. Reverberatory and rotary furnaces have minimal POM emissions
because of high exhaust temperatures and turbulence, which promote complete combustion of
organics. No controls for total hydrocarbons (THC) are necessary for these process
configurations (U.S. EPA, 1994b).
POM emissions from blast furnaces are dependent on the type of add-on control
used. An afterburner operated at 1,300°F (700°C) achieves about 90 percent destruction
efficiency of THC, including POM. Facilities with blast and reverberatory furnaces usually
combine the exhaust streams and vent the combined stream to an afterburner. The higher
operating temperature of the reverberatory furnace reduces the fuel needs of the afterburner so
that the afterburner is essentially "idling." Any temperature increase measured across the
afterburner is due to the heating value of organic compounds in the blast furnace exhaust. A
combined reverberatory and blast furnace exhaust stream ducted to an afterburner with an exit
temperature of 1,700°F (930°C) can achieve 98 percent destruction efficiency for THC
(U.S. EPA, 1994b).
4-271
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Additional controls used by secondary lead smelters include baghouses for
particulate and metals control, hooding and ventilation to a baghouse for process fugitives, and
scrubbers for hydrochloric acid (HC1) and SO2 control.
Emission Factors
Process emissions (i.e., those emitted from the smelting furnace's main exhaust)
contain metals, organics (including POM), HC1, and chlorine (C12). Process emissions also
contain criteria pollutants, including particulate matter (PM), volatile organic compounds (VOC),
carbon monoxide (CO), and SO2.
Blast furnaces are substantially greater sources of POM emissions than are
reverberatory or rotary furnaces. Low exhaust temperatures from the charge column (about
SOOT [430°C]) result in the formation of products of incomplete combustion from the organic
material in the feed material. Uncontrolled THC emissions from a typical 50,000 Mg/yr blast
furnace are about 310 tpy (280 Mg/yr) (U.S. EPA, 1994a).
Controlled blast furnace POM emissions are dependent on the add-on controls
that are used, which may be from 80 to 99 percent effective at reducing THC emissions. Rotary
and reverberatory furnaces have much higher exhaust temperatures than blast furnaces, about
1,800 to 2,200°F (980 to 1,200°C), and have much lower THC emissions because of more
complete combustion. THC emissions from a typical rotary furnace (15,000 Mg/yr capacity) are
about 38 tpy (34 Mg/yr). The majority of these emissions occur during furnace charging, when
the burner is cut back and the temperature is reduced. Emissions drop off sharply when charging
is completed and the is brought to normal operating temperature (U.S. EPA, 1994a).
POM emissions from reverberatory furnaces are even lower than those from rotary
furnaces because reverberatory furnaces are operated continuously rather than on a batch basis.
Test reports from three separate secondary lead smelters were used to develop
POM emission factors (Roy F. Weston, Inc, 1993a,b,c). All testing was conducted in support of
4-272
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the U.S. EPA Secondary Lead National Emission Standards for Hazardous Air Pollutants
(NESHAP) program. The three facilities tested represent the following process configurations: a
rotary smelting furnace equipped with a baghouse and SO2 scrubber; a blast furnace equipped
with an afterburner, baghouse, and SO2 scrubber; and a reverberatory and blast furnace with
exhaust from each furnace combined prior to a single afterburner, baghouse and SO2 scrubber.
Uncontrolled semi-volatile organic compound emissions were measured at all
three facilities using a semi-volatile organic sampling train (EPA Reference Method
SW846-0010). The semi-VOST sampling train captures both paniculate and vaporous POM
compounds. PAHs were measured at the blast furnace outlet (before the afterburner) at two
facilities, and at the rotary furnace outlet at one facility. THC emissions were measured at both
the blast furnace and rotary furnace outlets and at the afterburner outlets following the blast
furnaces. Three PAH compounds were analyzed at the tested facilities: naphthalene, chrysene,
and pyrene. Emission factors for these PAHs are shown in Table 4.4.5-1. Although PAH
emissions were not measured after the control device (afterburner or combined reverberatory and
blast furnace exhaust), controlled emission factors were estimated using the THC control
efficiency for the given process configuration. These estimates assume that the control efficiency
for the PAH species detected was equal to the control efficiency for THC.
One additional set of data has been identified that quantifies POM emissions from
a secondary lead smelter processing batteries (Bennet, 1979). In this study, four emission
samples were obtained from one facility. The data measured were PAH concentrations in the
stack gases following the final control device. The type of control device used was not specified.
The predominant PAHs measured were anthracene/phenanthrene and fluoranthene.
Benzo(a)pyrene was measured, but at levels only 0.1 percent of the anthracene/phenanthrene
levels.
4-273
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TABLE 4.4.5-1. PAH EMISSION FACTORS FOR SECONDARY LEAD SMELTING
SCC Number Emission Source
3-04-004-03 Blast Furnace
3-04-004-03 Blast Furnace
3-04-004-04 Rotary Furnace
Control
Device
None
Afterburner
None
Pollutant
Naphthalene
Naphthalene
Chrysene
Pyrene
Average Emission
!• actor in Ib/ton
(kg/Ms)"
0.182
(0.091 l)b
0.0125
(6.26E-03)b
1.83E-03
(9.17E-04)
7.22E-04
(3.61E-04)
Emission Factor Range in
Ib/ton
(kg/Mg)
0.0602 - 0.304
(0.0301 -0.152)
4.33E-4 - 0.0246
(2. 16E-4- 0.0123)
---
—
Emission
Factor
Rating
D
D
D
D
Reference
Weston, 1993a,b;
U.S. EPA, 1994c
Weston, 1993a,b;
U.S. EPA, 1994c
Weston, 1993c
Weston, 1993c
"Emission factors in Ib/ton (kg/Mg) of lead smelted.
bAverage emission factor from two facility test reports.
-------
The sampling and analytical procedures used during the tests were capable of
capturing and measuring both particulate and vapor phase POM. The majority of the POM
measured was caught in the water impingers. The average stack gas concentrations (ng/Nm3) of
four samples taken on two site visits to the same smelter were anthracene/phenanthrene 762.5;
methyl anthracenes 33.25; fluoranthene 970; pyrene 27.75; methyl pyrenes/fluoranthenes 2.25;
benzo(c)phenanthrene 12.75; chrysene/benz(a)anthracene 25.25; and benzo(a)pyrene 1
(Bennet et al., 1979).
Source Locations
In 1990, primary and secondary smelters in the United States produced
1,380,000 tons (1,255,000 Mg) of lead. Secondary lead smelters produced 946,000 tons
(860,000 Mg) or about 69 percent of the total refined lead produced in 1990, and primary
smelters produced 434,000 tons (395,000 Mg) (U.S. EPA, 1994a). Table 4.4.5-2 lists U.S.
secondary lead smelters according to their annual lead production capacity.
4-275
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TABLE 4.4.5-2. U.S. SECONDARY LEAD SMELTERS GROUPED
ACCORDING TO ANNUAL LEAD PRODUCTION CAPACITY
Smelter
Location
Small-Capacity Group:a
Delatte Metals
General Smelting and Refining Company
Master Metals, Inc.
Metals Control of Kansas
Metals Control of Oklahoma
Medium-Capacity Group:b
Doe Run Company
East Penn Manufacturing Company
Exide Corporation
Exide Corporation
GNB, Inc.
GNB, Inc.
Gulf Coast Recycling, Inc.
Refined Metals Corporation
Refined Metals Corporation
RSR Corporation
RSR Corporation
Schuylkill Metals Corporation
Tejas Resources, Inc.
Large-Capacity Group:0
Gopher Smelting and Refining, Inc.
GNB, Inc.
RSR Corporation
Sanders Lead Company
Schuylkill Metals Corporation
Ponchatoula, LA
College Grove, TN
Cleveland, OH
Hillsboro, KS
Muskogee, OK
Boss, MO
Lyon Station, PA
Muncie, IN
Reading, PA
Columbus, GA
Frisco, TX
Tampa, FL
Beech Grove, IN
Memphis, TN
City of Industry, CA
Middletown, NY
Forest City, MO
Terrell, TX
Eagan, MN
Vernon, CA
Indianapolis, IN
Troy, AL
Baton Rouge, LA
"Less than 22,000 tons (20,000 Mg).
^2,000 to 82,000 tons (20,000 to 75,000 Mg).
cGreater than 82,000 tons (75,000 Mg).
Source: U.S. EPA, 1994a.
4-276
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SECTION 4.4.5 REFERENCES
Bennet, R.L. et al. "Measurement of Polynuclear Aromatic Hydrocarbons and Other Hazardous
Organic Compounds in Stack Gases." In: Polynuclear Aromatic Hydrocarbons: Chemistry and
Biology - Carcinogenesis and Mutagenesis. Proceedings of the Third International Symposium
on Polynuclear Aromatic Hydrocarbons. Columbus, Ohio. P.W. Jones and P. Leber, eds. Ann
Arbor Science Publishers, Inc., Ann Arbor, Michigan. 1979.
National Research Council, Committee on Pyrene and Selected Analogues, Board on Toxicology
and Environmental Health Hazards, Commission on Life Sciences. Polycyclic Aromatic
Hydrocarbons: Evaluation of Sources and Effects, p. 2-35. 1983.
U.S. Environmental Protection Agency. Secondary Lead Smelting Background Information
Document for Proposed Standards: Volume 1. Office of Air Quality Planning and Standards,
Research Triangle Park, North Carolina. EPA-450/R-94-024a. pp. 2-1 to 2-36. June 1994a.
U.S. Environmental Protection Agency. Secondary Lead Smelting Background Information
Document for Proposed Standards: Volume 1. Office of Air Quality Planning and Standards,
Research Triangle Park, North Carolina. EPA-450/R-94-024a. pp. 3-1 to 3-13. 1994b.
U.S. Environmental Protection Agency. Secondary Lead Smelting Background Information
Document for Proposed Standards: Volume 2 - Appendices. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. EPA-450/R-94-024b. pp. A-30 and A-40.
1994c.
Roy F. Weston, Inc. Testing on Selected Sources at a Secondary Lead Smelter. Summary of
Results, Draft Data Tables. East Penn Manufacturing Company, Lyon Station, Pennsylvania.
Prepared for U.S. Environmental Protection Agency, Emission Measurement Branch, Research
Triangle Park, North Carolina. EPA Contract No. 68D10104 and 68D20029. Tables 3-25, 3-27.
1993a.
Roy F. Weston, Inc. Emission Test Report - HAP Emission Testing on Selected Sources at a
Secondary Lead Smelter. Schuylkill Metals Corporation, Forest City, Missouri. Prepared for
U.S. Environmental Protection Agency, Emission Measurement Branch, Research Triangle Park,
North Carolina. EPA Contract No. 68D10104. pp. 3-38, 3-39, 3-51. 1993b.
Roy F. Weston, Inc. Emission Test Report - HAP Emission Testing on Selected Sources at a
Secondary Lead Smelter. Tejas Resources, Inc., Terrell, Texas. Prepared for
U.S. Environmental Protection Agency, Emission Measurement Branch, Research Triangle Park,
North Carolina. EPA Contract No. 68D10104. pp. 3-32 to 3-34. 1993c.
4-277
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4.5 PETROLEUM REFINING
Crude oil contains small amounts of naturally occurring aromatics, including
some POM, that may be emitted from some processes and operations at petroleum refineries.
Other processes may form POM, which may be emitted at the point of generation or downstream
in another operation. A flow diagram of processes likely to be found at a model refinery is
shown in Figure 4.5-1. The arrangement of these processes varies among refineries, and few, if
any, employ all of these processes.
Processes at petroleum refineries can be grouped into five types: (1) separation
processes, (2) conversion processes, (3) treating processes, (4) auxiliary processes and operation,
and (5) feedstock/product storage and handling. These operations are discussed briefly below.
The first phase in petroleum refining operations is the separation of crude oil into
its major constituents using four separation processes: (1) desalting, (2) atmospheric distillation,
(3) vacuum distillation, and (4) light ends recovery.
To meet the demands for high-octane gasoline, jet fuel, and diesel fuel,
components such as residual oils, fuel oils, and light ends are converted to gasolines and other
light fractions using one or more of the following conversion processes: (1) catalytic cracking
(fluidized-bed and moving-bed), (2) thermal processes (coking, and visbreaking), (3) alkylation,
(4) polymerization, (5) isomerization, and (6) reforming.
Petroleum treating processes stabilize and upgrade petroleum products by
separating them from less desirable products. Among the treating processes are
(1) hydrotreating, (2) chemical sweetening, (3) de-asphalting, and (4) asphalt blowing.
4-278
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FiMl Oat and LPO
VO
Gasofcn, Naphtha. Mtddla DbtMatas
Nod: (.attars eorraipond to potanllal sources of banzana ambslons. listed ki Tablo 8-5.
Figure 4.5-1. Process Flow Diagram for a Model Petroleum Refinery
Source: Radian, 1980.
-------
Auxiliary processes and operations include process heaters and stationary
compressor engines (emissions from which are discussed in other sections of this document),
sulfur recovery units, blowdown systems, flares, cooling towers, and wastewater treatment
facilities.
Finally, all refineries have a feedstock/product storage area (commonly called a
"tank farm") with storage tanks whose capacities range from less than 1,000 barrels to more than
500,000 barrels. Feedstock/product handling operations (transfer operations) consist of the
loading and unloading of transport vehicles (including trucks, rail cars, and marine vessels).
Emissions that are associated with these operations are discussed in Section 4.12.8 as part of
gasoline distribution and marketing.
Emissions of HAPs from the different processes in petroleum refineries have been
investigated recently in support of Federal NESHAP development; a MACT standard for the
petroleum refinery source category was promulgated in 1995. The investigations did not focus
on POM because of their relative insignificance compared to lighter aromatics. However, some
indications of total POM quantities emitted from various processes did surface, and emissions of
one PAH, naphthalene, were detected from some processes, which were not reported previously.
In general, the largest sources of POM emissions from petroleum refinery
processes are process heaters and catalytic cracking units. Process heater emissions are discussed
in Section 4.1.2 of this document; emissions from FCC units are discussed next. Other sources
of POM emissions, primarily naphthalene, include process vents on the sulfur recovery, thermal
coking, and blowdown systems, and from wastewater. Because the data for emissions from these
sources are limited and the emissions are relatively minor, the sources are not described in detail;
rather, emissions and controls are summarized in Section 4.5.2.
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4.5.1 Catalytic Cracking Units
Process Description
Catalytic cracking processes are the means by which the production of gasoline
can be substantially increased from a given amount of crude oil. Heavier feedstocks such as
atmospheric or vacuum gas oils are cracked in fluidized or moving-bed units to produce slurry
oil, light cycle oil, cracked gasoline, light gases, and coke (Radian, 1980). The cracking takes
place in the presence of a catalyst, which can become deactivated through the continual
deposition of coke (i.e., carbon) on active sites. To combat catalyst degradation, catalysts are
regenerated by combusting the coke deposits on the catalyst. This combustion of coke during
catalyst regeneration has been found to form POM emissions (Hangebrauck et al., 1967).
Two types of catalytic crackers are used in the petroleum industry: fluidized-bed
and moving-bed designs. There are two types of moving-bed designs: Thermofor® catalytic
cracking (TCC) units and Houdriflow® catalytic cracking (HCC) units. Fluidized-bed catalytic
crackers (FCC) greatly dominate over the moving-bed type, constituting well over 90 percent of
total cracking feed capacity. The industry has been generally phasing out the use of moving-bed
units since 1980 in favor of the more efficient FCC units (Radian, 1980).
A process flow diagram of a typical FCC unit is shown in Figure 4.5-2
(Radian, 1980). In the FCC process, hot regenerated catalyst, mixed with hydrocarbon feed, is
transported into the cracking reactor. The reactor, which is maintained at about 900°F (480°C)
and 15 psig, contains a bed of powdered silica-alumina type catalyst which is kept in a fluidized
state by the flow of vaporized feed material and steam (Radian, 1980; Hangebrauck et al., 1967).
Cracking of the feed, which occurs in the riser leading to the reactor and in the fluidized bed,
causes a deposit of coke to form on the catalyst particles. A continuous stream of spent catalyst
is withdrawn from the reactor and steam-stripped to remove hydrocarbons. The catalyst particles
are then pneumatically conveyed to a catalyst regeneration unit. Hydrocarbon vapors from the
cracking process are fractionated in a distillation column to produce light hydrocarbons, cracked
gasoline, and fuel oil (Radian, 1980).
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STEAM
N)
OO
to
FLUE GAS (POM)
EMISSIONS
r
ESP
CONTROL
F
CATALYS7
FINES
POM EMISSIONS
GAS AND
TOWER
BOTTOMS
GAS 'OIL
GAS OIL
o
te.
IU
Figure 4.5-2. Diagram of a Fluid-Bed Catalytic Cracking Process
Source: Radian, 1980.
-------
In the catalyst regeneration unit, coke deposits are burned off at temperatures
nearly 1,000°F (540°C) and pressures ranging from 2 to 20 psig (Hangebrauck, 1967). This
coke combustion process is the source of POM emissions in the regeneration portion of FCC
units (Radian, 1980; Hangebrauck, 1967). The regenerated catalyst is continuously returned to
the cracking reactor. Heat added to the catalyst during regeneration (coke combustion) furnishes
much of the required heat for the cracking reaction (Radian, 1980). Uncontrolled regenerator
flue gases contain a high amount of CO along with other unburned hydrocarbons (potentially
including POM compounds). These flue gases can be vented directly to the atmosphere or to a
CO waste heat boiler (Radian, 1980; Hangebrauck et al., 1967).
Moving-bed cracking units are similar to FCC units but use beaded or pelleted
catalysts (Radian, 1980; Hangebrauck et al., 1967). In both TCC and HCC units, the cracking
process is initiated by having regenerated catalyst and vaporized hydrocarbon feed enter the top
of the cracking reactor chamber and travel co-currently downward through the vessel. As the
cracking process proceeds, synthetic crude product is withdrawn and sent to the synthetic crude
distillation tower for processing into light fuels, heavy fuels, catalytic gasoline, and wet gas
(Radian, 1980;. At the base of the reactor, the catalyst is purged with steam to remove
hydrocarbons and is then gravity fed into the catalyst regeneration chamber.
In the regeneration chamber, combustion air is added at a controlled rate to burn
off catalyst coke deposits. As in FCC units, burning coke produces POM emissions that are
released in TCC and HCC catalyst regenerator flue gases. Regenerated catalyst is collected at the
bottom of the chamber and is conveyed by airlift to a surge hopper above the cracking reactor
where it can be gravity-fed back into the cracking process (Radian, 1980).
Flue gases from TCC and HCC units are either vented directly to the atmosphere
or to a CO waste heat boiler. Waste heat boilers that are fired with an auxiliary fuel or contain a
catalyst are reported to have been 99 percent efficient in reducing PAH emissions from a
regeneration unit (Radian, 1980). In several installations, paniculate matter emissions from the
waste heat boiler are controlled by an ESP (Radian, 1980). Catalytic cracking units constructed
after June 1973 are subject to a new source performance standard that limits CO and paniculate
4-283
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matter emissions to such a level that a waste heat boiler and ESP are generally required for
compliance (Radian, 1980). Cyclones and scrubbers have also been used for added control.
Some TCC units have also been equipped in some installations with direct-fired
afterburners called plume burners. The plume burner is a secondary stage of combustion built
into the catalyst regeneration chambers. This type of burner successfully increases the clarity of
plumes from regeneration flue gases; however, compared to a CO waste heat boiler, the plume
burner is ineffective at reducing POM emissions (Hangebrauck, 1967).
Another way to reduce POM emissions from the catalyst regenerators is to
achieve a more complete combustion of CO to CO2. Processes such as the Universal Oil
Products (UOP) hot regeneration and Amoco Ultracat® have been developed to aid in the
achievement of lower overall POM emissions. The relatively higher temperatures for catalyst
regeneration used in the UOP process serves to improve coke combustion efficiency and thus
potentially reduce POM formation and emissions. One drawback to the UOP process is that due
to its higher temperatures, special materials of construction are required, thus making it more
suitable for new cracking units as opposed to existing units. The Amoco process, however, is
based on improving the catalytic reactor efficiency and allowing more complete combustion to
occur in the catalyst regenerator without having to operate at higher temperatures. Because
changes in basic equipment are minimal with the Amoco process, it is more amenable for
retrofitting existing units (Radian, 1980).
Emission Factors
Emission factors for the catalyst regenerator portion of fluidized- and moving-bed
catalytic cracking units are presented in Table 4.5-1 (Hangebrauck et al., 1967). As indicated by
the date of the reference, POM emission data from catalytic cracking have not been updated since
Hangebrauck summarized these emission factors. The only newer data that are available for
POM from catalytic cracking are those for naphthalene emissions (Radian, 1991).
4-284
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The emission factors that were reported by Hangebrauck et al. (1967) for all FCC,
TCC, and HCC units exhibit a large amount of variability. In uncontrolled FCC units, pyrene,
phenanthrene, and fluoranthene were the predominant compounds measured. Perylene,
anthracene, and coronene were not detected in uncontrolled emissions from the FCC unit.
Benzo(a)pyrene levels were found to be relatively minor (average of 3.74E10-6 Ib
[1.69E10-7 kg] per barrel of oil feed versus an average of 2.94E10-4 Ib [1.33E10-4 kg] per barrel
of oil feed for phenanthrene; a standard barrel of oil contains 42 gallons [160 liters]). The
positive effect of CO waste heat boilers as control devices for FCC unit regenerator flue gases
can also be seen (Hangebrauck et al., 1967).
Emissions of PAH were highest in general from the controlled TCC unit (air lift
type) and the uncontrolled HCC unit. In the air lift TCC unit, pyrene, phenanthrene,
benzo(ghi)perylene, and benzo(a)pyrene emission levels were the highest of the ten PAH
measured. Similarly, benzo(ghi)perylene, benzo(e)pyrene, pyrene, and benzo(a)pyrene were the
most significant compounds measured in uncontrolled HCC unit emissions. Both types of TCC
units were equipped with plume burners. The data for the HCC unit suggests the effectiveness of
venting regenerator emissions to CO waste heat boilers for PAH emission control. For each of
the ten PAH compounds measured, the CO waste heat boiler reduced uncontrolled HCC
regenerator emissions by greater than 99 percent.
Data obtained to support the development of the Petroleum Refinery NESHAP
was used to calculate an emission factor for naphthalene from an FCC unit without a CO waste
heat boiler (i.e., uncontrolled) (Radian, 1991). This emission factor, which is presented in
Table 4.5-1, is based on information provided by only one refinery and may not be representative
of similar units. Data for total POM were also provided in response to the EPA ICR and
Section 114 surveys (Radian, 1991). Total annual POM emissions from an uncontrolled catalytic
cracking unit were calculated to be 0.0041 Ib (0.0018 kg) per barrel of oil charged, which is
similar in value to the emission factor for naphthalene. Again, these data are not necessarily
representative of the industry as a whole, but they give some small indication of the level of
POM emissions that can be expected from today's catalytic cracking units.
4-285
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TABLE 4.5-1. PAH EMISSION FACTORS FOR PETROLEUM CATALYTIC CRACKING
CATAYST REGENERATION UNITS
SCC Number Emission Source Control Device Pollutant
3-06-002-01 Fluid Catalytic Cracking Unit Uncontrolled Benzo(a)pyrene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Naphthalene
oo Phenanthrene
ON
Pyrene
Benzo(e)pyrene
Benzo(a)pyrene
Benzo(ghi)perylene
Fluoranthene
Pyrene
Benzo(e)pyrene
Average Emission
Factor in Ib/barrel"
(kg/barrel)
3.7E-07
(1.7E-07)
(<6.9E-07)
<3.2E-07
(<1.5E-07)
1.5E-05
(6.7E-06)
1.3E-06
(6.0E-07)
<3.0E-()4
(<1.3E-04)
2.1E-05
(9.4E-06)
2.7E-06
(1.2E-06)
2.4E-08
(1.1E-08)
4.0E-08
(1.8E-08)
1.3E-07
(5.9E-08)
2.0E-07
(9.2E-08)
2.9E-08
(1.3E-08)
Emission
Factor
Rating
D
D
D
D
E
D
D
D
D
D
D
D
D
Reference
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al..
Radian, 1991
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
1967
1967
1967
1967
1967
1967
1967
1967
1967
1967
1967
1967
(continued)
-------
TABLE 4.5-1. (Continued)
K)
SCC Number Emission Source Control Device Pollutant
3-06-003-01 Moving-bed Catalytic Cracking Plume Burner Benzo(a)pyrene
Process - Thermofor (airlift)
Anthracene
Bcnzo(ghi)perylene
Fluoranthene
Plienanthrene
Pyrene
Anthanthrene
Benzo(e)pyrene
Coronene
Perylene
3-06-003-01 Moving-bed Catalytic Cracking Plume Burner Benzo(a)pyrene
Process - Thermofor (bucket lift)
Fluoranthene
Pyrene
Average Emission
Factor in lb/barrela
(kgftarrel)
1.8E-04
(7.9E-05)
3.3E-06
(1.5E-05)
1.3E-04
(5.7E-05)
2.9E-05
(1.3E-05)
5.6E-04
(2.5E-04)
4.7E-04
(2.1E-04)
5.5E-06
(2.5E-06)
1.1E-04
(4.8E-05)
2.7E-07
(1.2E-07)
1.8E-05
(8.1E-06)
3.5E-08
(1.6E-08)
1.8E-07
(8.3E-08)
7.1E-07
(3.2E-07)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
D
Reference
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et at.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
1967
1967
1967
1967
1967
1967
1967
1967
1967
1967
1967
1967
1967
(continued)
-------
TABLE 4.5-1. (Continued)
OO
ex
SCC Number Emission Source
3-06-003-01 Moving-bed Catalytic Cracking
(continued) Process - Thermofor (bucket lift)
(continued)
3-06-003-01 Moving-bed Catalytic Cracking
Process - Houdriflow
3-06-003-01 Moving-bed Catalytic Cracking
Process - Houdriflow
Control Device Pollutant
Plume Burner Benzo(e)pyrene
(continued)
Uncontrolled Benzo(a)pyrene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Phenanthrene
Pyrene
Anthanthrene
Benzo(e)pyrene
Coronene
Perylene
CO Waste Heat Boiler Benzo(a)pyrene
Anthracene
Average Emission
Factor in lb/barrela
(kg/barrel)
9.1E-08
(4.1E-08)
4.8E-04
(2.2E-04)
3.2E-06
(1.5E-06)
7.5E-04
(3.4E-04)
2.2E-05
(9.9E-06)
5.5E-05
(2.5E-05)
2.9E-04
(1.3E-04)
3.7E-05
(1.7E-05)
7.6E-04
(3.5E-04)
4.1E-05
(1.9E-05)
7.5E-05
(3.4E-05)
l.OE-07
(4.5E-08)
1.7E-08
(7.9E-09)
Emission
Factor
Rating
D
E
E
E
E
E
E
E
E
E
E
E
E
Reference
Hangebrauck et al., 1967
Hangebrauck et al., 1967
Hangebrauck et al., 1967
Hangebrauck et al., 1967
Hangebrauck et al., 1967
Hangebrauck et al., 1967
Hangebrauck etal., 1967
Hangebrauck et al., 1967
Hangebrauck et al., 1967
Hangebrauck et al., 1967
Hangebrauck et al., 1967
Hangebrauck et al., 1967
Hangebrauck et al., 1967
(continued)
-------
TABLE 4.5-1. (Continued)
S)
oo
SCC Number Emission Source Control Device Pollutant
3-06-003-01 Moving-bed Catalytic Cracking CO Waste Heat Boiler Bcnzo(ghi)perylene
(continued) Process - Houdriflow (continued)
(continued)
Fluoranthene
Phenanthrene
Pyrene
Anthanthrene
Bcnzo(e)pyrene
Coronene
Pcrylene
Average Emission
Factor in lb/barrela
(kg/barrel)
2.8E-07
(1.3E-07)
5.1E-08
(2.3E-08)
1.8E-07
(8.3E-08)
8.6E-08
(3.9E-08)
7.1E-09
(3.2E-09)
2.1E-07
(9.7E-08)
1.8E-08
(8.0E-09)
1.1E-08
(4.8E-09)
Emission
Factor
Rating
E
E
E
E
E
E
E
E
Reference
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al.,
Hangebrauck et al..
1967
1967
1967
1967
1967
1967
1967
1967
'Emission factors are expressed in Ib (kg) of pollutant per barrel of oil (fresh feed and recycle) charged.
-------
Source Locations
As of January 1992, there were 192 petroleum refineries in the United States, with
a total crude capacity of 15.3 million barrels per calendar day. The majority of refinery capacity
(54 percent) was located in Texas, Louisiana, and California. Other regions with significant
refinery capacities were the Chicago, Philadelphia, and Puget Sound areas. Only about
two-thirds of these refineries operate catalytic crackers.
4.5.2 Other Petroleum Refinery Sources
Process Description
The recent MACT standard development effort has indicated the possibility of
other minor POM sources in petroleum refineries. Some refineries reported that naphthalene was
emitted from process vents on the sulfur recovery, thermal coking, and blowdown systems, and
points in the wastewater treatment system. The first three processes may generate POM or may
simply emit POM such as naphthalene that are already present in the material being processed.
Because these are minor sources and little data are available, the processes are not described.
Consult the references should be for more detail.
Emission Factors
Even though a few refineries reported that naphthalene was present, emission
factors could be developed only for two points in the wastewater treatment process: the oil-water
separator and biotreatment. Naphthalene emissions from an oil-water separator were calculated
to be on average 1.45 Ib (0.65 kg) per million gallons of refinery wastewater treated. An average
factor for naphthalene emissions from a biotreatment unit was calculated as 0.565 Ib (0.255 kg)
per million gallons of refinery wastewater treated. As with the naphthalene emission factor for
an uncontrolled FCC unit, it must be emphasized that these data are from a limited number of
facilities. No claim is-made that these are representative values; rather, they are the only data
4-290
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available and serve only to give some indication of the type of refinery processes that may
generate POM.
The process vent provisions included in the Petroleum Refinery NESHAP affect
organic HAP emissions from miscellaneous process vents throughout a refinery. For
miscellaneous process vents, the most reported controls were flares, incinerators, and/or boilers.
Other controls for miscellaneous process vents reported by refineries include scrubbers, ESPs,
fabric filter, and cyclones. The wastewater provisions of the Petroleum Refining NESHAP affect
wastewater collection and treatment systems emissions as well. Therefore, emissions from these
other sources along with catalytic cracking units may be significantly reduced after the Petroleum
Refinery NESHAP is fully implemented (Zarate, 1992).
Source Locations
As stated previously, there are nearly 200 refineries in the United States.
However, not all of them may operate sulfur recovery, thermal coking, or wastewater systems,
although as Vvith catalytic cracking, the majority of the refineries have these systems which can
potentially emit naphthalene.
4-291
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SECTION 4.5 REFERENCES
Draft Memorandum from Zarate, M.A., Radian Corporation, to Durham, J.F.,
U.S. Environmental Protection Agency. "Summary of Nationwide Hazardous Air Pollutant
Emission Estimates from Process Vents for Petroleum Refineries." May 12,1992.
Hangebrauck, R.P. et al. Sources of Polynuclear Hydrocarbons in the Atmosphere. Public
Health Service, U.S. Department of Health, Education, and Welfare, Cincinnati, Ohio. Public
Health Service Report No. AP-33. pp. 27-28. 1967.
Radian Corporation. Summary of Hazardous Air Pollutant Emissions from Selected Petroleum
Refineries. Prepared for U.S. Environmental Protection Agency, Chemicals and Petroleum
Branch, Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina.
November 1991.
Radian Corporation. Assessment of Atmospheric Emissions from Petroleum Refining. Prepared
for U.S. Environmental Protection Agency, Industrial Environmental Research Laboratory,
Research Triangle Park, North Carolina. EPA-600/2-80-075e. pp. 192-203. July 1980.
4-292
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4.6 ASPHALT PRODUCTS
Asphaltic material is obtained toward the end of fractional distillation of crude oil,
has two main end-uses: asphalt roofing products and asphalt paving concrete. The
manufacturing processes for these two product lines and the emissions associated with their
manufacture are described in this section.
4.6.1 Asphalt Roofing Manufacturing
Process Description
The production of asphalt roofing materials is a commonly found industry owing
to the widespread usage of the products in the United States. The asphalt roofing industry
manufactures asphalt-saturated felt rolls, shingles, roll roofing with mineral granules on the
surface, and smooth roll roofing that may contain a small amount of mineral dust or mica on the
surface. Most of these products are used in roof construction, but small quantities are used in
walls and other building applications (U.S. EPA, 1995).
Asphalt Delivery. Handling, and Storage—The first step in the process of making asphalt roofing
products is the delivery, handling, and storing of asphalt flux. Asphalt flux is the term commonly
used in this industry for the asphaltic material that is derived from crude oil. The delivery,
handling, and storing of asphalt flux at the asphalt roofing plant has been identified as a potential
source of organic emissions, including POM.
Asphalt is normally delivered to an asphalt roofing plant in bulk by pipeline,
tanker truck, or railcar. Bulk asphalt delivered in liquid form may range in temperature from
200 to 400°F (93 to 204°C), depending on the type of asphalt and local practice
(U.S. EPA, 1980; Kelly, 1983; Gerstle, 1974).
With bulk liquid asphalt, the most common method of unloading is to couple a
flexible pipe to the tanker and pump the asphalt directly into the appropriate storage tanks. The
4-293
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tanker cover is partially open during the transfer. Because this is a closed system, the only
potential sources of emissions are the tanker and the storage tanks. The magnitude of the
emissions from the tanker is at least partially dependent on how far the cover is opened.
Another unloading procedure, of which there are numerous variations, is to pump
the hot asphalt into a large open funnel that is connected to a surge tank. From the surge tank,
the asphalt is pumped directly into storage tanks. Emission sources under the surge tank
configuration are the tanker, the interface between the tanker and the surge tank, the surge tank,
and the storage tanks. Emissions from these sources are primarily organic particulate. The
quantity of emissions depends on the asphalt temperature and on the asphalt characteristics.
After delivery, asphalt flux is usually stored at 124 to 174°F (51 to 79°C),
although storage temperatures of up to 450°F (232 °C) have been noted. The lower temperatures
are usually maintained with steam coils in the tanks. Oil- or gas-fired preheaters are used to
maintain the asphalt flux at temperatures above 200°F (93°C) (U.S. EPA, 1980; Kelly, 1983;
Gerstle, 1974).
Asphalt flux is usually transferred from storage and around the roofing plant by
closed pipeline. Barring leaks, the only potential emissions would come from the end-points of
the pipes. These end-points are the storage tanks, the asphalt heaters (if not of the closed-tube
type), and the air-blowing stills.
Asphalt Air-Blowing—Before use, asphalt flux must first be converted to either of two roofing
grades of asphalt: saturant or coating. Saturant and coating asphalts are primarily distinguished
by their softening points. The softening point of saturant asphalts is 104 to 165°F (40 to 74°C);
coating asphalts soften at about 230°F (110°C). These softening points are achieved by
"blowing" hot asphalt flux, that is, by blowing air through tanks of hot asphalt flux. This
blowing process has been identified as a primary source of POM emissions.
The configuration of a typical asphalt air-blowing operation is shown in
Figure 4.6.1-1 (U.S. EPA, 1995). This operation consists primarily of a blowing still,
4-294
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KNOCKOUTBOX
OR CYCLONE
AIR, WATER VAPOR, OIL,
VOC8.ANDPM
ASPHALT
FLUX
VENT TO
ATMOSPHERE *
BLOWING
sna
CONTAINING
ASPHALT
VENT TO
CONTROL OR 4
ATMOSPHERE
>. BLOWN ASPHALT
-HEATER
ASPHALT FLUX
STORAGE TANK
Figure 4.6.1 -1. Asphalt Blowing Process Flow Diagram
Source: U.S. EPA, 1995.
4-295
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which is a tank with a sparger fitted near its base. The purpose of the sparger is to increase
contact between the blowing air and the asphalt. Air is forced through holes in the sparger into a
tank of hot asphalt flux. The air rises through the asphalt and initiates an exothermic oxidation
reaction. Oxidizing the asphalt has the effect of raising the softening temperature, reducing
penetration, and modifying other characteristics. Inorganic salts such as ferric chloride (FeCl3)
may be used as catalysts added to the asphalt flux during air blowing to facilitate these
transformations (U.S. EPA, 1995). The time required for air blowing of asphalt depends on a
number of factors, including the characteristics of the asphalt flux, the characteristics desired for
the finished product, reaction temperature, type of still used, air injection rate, and the efficiency
with which air entering the still is dispersed throughout the asphalt. Blowing times may vary in
duration from 30 minutes to 12 hours, with typical times from 1 to 4.5 hours (U.S. EPA, 1980;
U.S. EPA, 1995).
Asphalt blowing is a highly temperature-dependent process because the rate of
oxidation increases rapidly with increases in temperature. Asphalt is preheated to 400 to 470°F
(204 to 243 °C) before blowing is initiated to ensure that the oxidation process will start at an
acceptable rate. Conversion does take place at lower temperatures, but is much slower. Because
of the exothermic nature of the reaction, the temperature of the asphalt rises as blowing proceeds,
which, in turn, further increases the reaction rate. Asphalt temperature is normally kept at about
500°F (260°C) during blowing by spraying water onto the surface of the asphalt, although
external cooling may also be used to remove the heat of reaction. The allowable upper limit to
the reaction temperature is dictated by safety considerations, with the maximum temperature of
the asphalt usually kept at least 50°F (28 °C) below the flash point of the asphalt being blown
(U.S. EPA, 1980).
The design and location of the sparger in the blowing still governs how much of
the surface area of the asphalt is physically contacted by the injected air, and the vertical height
of the still determines the time span of this contact. Vertical stills, because of their greater head
(asphalt height), require less air flow for the same amount of asphalt-air contact. Both vertical
and horizontal stills (Figure 4.6.1-2 and Figure 4.6.1-3) are used for asphalt blowing, but in new
construction, the vertical type is preferred by the industry because of the increased asphalt-air
4-296
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KNOCK OUT BOX
OR
CYCLONE V
WATER VALVE
WATE
o
•s
o
ac.
ui
AIR COMPRESSOR
STILL
Figure 4.6.1-2. Typical Configuration of a Vertical Asphalt Air Blowing Still
Source: U.S. EPA, 1980.
4-297
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N>
VO
oo
I
CO
i
o
a.
O
ee.
AIR COMPRESSOR
Figure 4.6.1-3. Typical Configuration of a Horizontal Asphalt Air Blowing Still
Source: U.S. EPA, 1980.
-------
contact and consequent reduction in blowing times (U.S. EPA, 1980). Also, asphalt losses from
vertical stills are reported to be less than those from horizontal stills. All recent blowing still
installations have been of the vertical type (U.S. EPA, 1995).
Asphalt blowing can be either a batch process or a continuous operation; however,
the majority of facilities use a batch process. Asphalt flux is sometimes blown by the oil refiner
or asphalt processor to meet the roofing manufacturer's specifications. Many roofing
manufacturers, however, purchase the flux and carry out their own blowing.
Asphalt Saturation-After asphalt has been blown into saturant or coating asphalt, it is used to
produce asphalt felt and coated asphalt roofing and siding products in the processes depicted in
Figures 4.6.1-4 and 4.6.1-5. The processes are identical to the point at which the material is to be
coated. A roll of felt is installed on the felt reel and unwound onto a dry floating looper. The dry
floating looper provides a reservoir of felt material to match the intermittent operation of the felt
roller to the continuous operation of the line. Felt is unwound from the roll at a faster rate than is
required by the line, with the excess being stored in the dry looper. The flow of felt to the line
and the tension on the material are kept constant by raising the top set of rollers and increasing
looper capacity. The opposite action occurs when a new roll is being put on the felt reel and
spliced in, and the felt supply ceases temporarily.
Following the dry looper, the felt enters the saturator, another point of POM
emissions within the asphalt roofing process. Moisture is driven out of the felt in the saturator
and the felt fibers and intervening spaces are filled with saturant asphalt. If a fiberglass mat web
is used instead of felt, the saturation step and the subsequent drying-in process are bypassed. The
saturator also contains a looper arrangement, which is almost totally submerged in a tank of
asphalt maintained at a temperature of 450 to 500°F (232 to 260°C). The absorbed asphalt
increases the sheet or web weight by about 150 percent. At some plants, the felt is sprayed on
one side with asphalt to drive out the moisture prior to dipping. This approach reportedly results
in higher POM emissions than does use of the dip process alone (U.S. EPA, 1980).
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VENT TO CONTROL
EQUIPMENT
FLOATING LOOPER
VENT TO CONTROL EQUIPMENT
OR ATMOSPHERE
BURNER
SATURATOR ENCLOSURE -
ROLL WINDER
FOR ASPHALT
FELT
Figure 4.6.1-4. Asphalt-saturated Felt Manufacturing Process
Source: U.S. EPA, 1995.
4-300
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X A A
TO CONTROL
EQUIPMENT
(5-
GRANULES AND SAND
STORAGE
b YXXY
SCREW CONVEYO
K
ELE
r^
VATOR
BAGHOUSL
BLOWER
CONTROL CONVEYOR
EQUIPMENT
Figure 4.6.1-5. Organic Shingle and Roll Manufacturing Process Flow Diagram
Source: U.S. EPA, 1995.
4-301
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The saturated felt then passes through drying-in drums and onto the wet looper,
sometimes called the hot looper. The drying-in drums press surface saturant into the felt.
Depending on the required final product, additional saturant may also be added at this point. The
amount of absorption depends on the viscosity of the asphalt and the length of time the asphalt
remains fluid. The wet looper increases absorption by providing time for the saturant asphalt to
penetrate the felt. The wet looper operation has been shown to be a source of organic paniculate
emissions within the asphalt roofing process; however, the portion that is POM has not been
defined (U.S. EPA, 1980; Kelly, 1983).
Asphalt Coating and Surfacing-If saturated felt is being produced, the sheet passes directly to the
cool-down section. For surfaced roofing products, however, the saturated felt is carried to the
coater station, where a stabilized asphalt coating is applied to both the top and bottom surfaces.
Stabilized coating contains a mineral stabilizer and a harder, more viscous coating asphalt that
has a higher softening point than saturant asphalt. The coating asphalt and mineral stabilizer are
mixed in approximately equal proportions. The mineral stabilizer may consist of finely divided
lime, silica, slate dust, dolomite, or other mineral materials.
The coating asphalt and mineral stabilizer are combined in the coater-mixer. The
asphalt is piped into the coater-mixer at about 450 to 500°F (232 to 260°C), and the mineral
stabilizer is delivered by screw conveyor. There is often a preheater immediately ahead of the
coater-mixer to dry and preheat the material before it is fed into the coater-mixer. This
eliminates moisture problems and helps to maintain the temperature above 320°F (160°C). The
coater-mixer is usually covered or enclosed, with an exhaust pipe for the air displaced by (or
carried with) the incoming materials. The mineral-stabilized coating asphalt is then piped to the
coating pan.
The weight of the finished product is controlled by the amount of coating asphalt
used. The coater rollers can be moved closer together to reduce the amount of coating applied to
the felt, or separated to increase it. Many modern plants are equipped with automatic scales that
weigh the sheets in the process of manufacture and warn the coater operator when the product is
running under or over specifications.
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The next step in the production of coated roofing products is the application of
mineral surfacing. The surfacing section of the roofing line usually consists of a
multi-compartmented granule hopper, two parting agent hoppers, and two large press rollers.
The hoppers are fed through flexible hoses from one or more machine bins above the line. These
machine bins provide temporary storage and are sometimes called surge bins. The granule
hopper drops colored granules from various compartments onto the top surface of the moving
sheet of coated felt in the sequence necessary to produce the desired color pattern on the roofing.
This step is not required for smooth-surface products (U.S. EPA, 1980).
Parting agents such as talc and sand (or some combination thereof) are applied to
the top and back surfaces of the coated sheet from parting agent hoppers. These hoppers are
usually of an open-top, slot-type design, slightly longer than the coated sheet is wide, with a
screw arrangement for distributing the parting agent uniformly throughout its length. The first
hopper is positioned between the granule hopper and the first large press roller, and 8 to
12 inches. (0.2 to 0.3 m) above the sheet. It drops a generous amount of parting agent onto the
top surface of the coated sheet and slightly over each edge. Collectors are often placed at the
edges of the sheet to pick up this overspray, which is then recycled to the parting agent machine
bin by open screw conveyor and bucket elevator. The second parting agent hopper is located
between the rollers and dusts the back side of the coated sheet. Because of the steep angle of the
sheet at this point, the average fall distance from the hopper to the sheet is usually somewhat
greater than on the top side, and more of the material falls off the sheet (U.S. EPA, 1980).
In a second technique used to apply backing agent to the back side of a coated
sheet, a hinged trough holds the backing material against the coated sheet and only material that
will adhere to the sheet is picked up. When the roofing line is not operating, the trough is tipped
back so that no parting agent will escape past its lower lip.
Immediately after application of the surfacing material, the sheet passes through
the cool-down section. Here the sheet is cooled rapidly by passing it around water-cooled rollers
in an abbreviated looper arrangement. Usually, water is sprayed on the surfaces of the sheet to
speed the cooling process.
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Following cooling, self-sealing coated sheets usually have an asphalt seal-down
strip applied. The strip is applied by a roller, which is partially submerged in a pan of hot sealant
asphalt. The pan is typically covered to minimize fugitive emissions. No seal-down strip is
applied to standard shingle or roll goods products. Some products are also texturized at this
point by passing the sheet over an embossing roll that forms a pattern in the surface of the coated
sheet (U.S. EPA, 1980).
Cooling and Finishing—The cooling process for both asphalt felt and coated sheets is completed
in the next processing station, known as the finish looper. In the finish looper, sheets are allowed
to cool and dry gradually. Secondly, the finish looper provides line storage to match the
continuous operation of the line to the intermittent operation of the roll winder. It also allows
time for quick repairs or adjustments to the shingle cutter and stacker during continuous line
operation or, conversely, allows cutting and packaging to continue when the line is down for
repair. Usually, this part of the process is enclosed to keep the final cooling process from
progressing too rapidly. In cold weather, heated air is sometimes used to retard cooling.
Following finishing, asphalt felt to be used in roll goods is wound on a mandrel,
cut to the proper length, and packaged. When shingles are being made, the material from the
finish looper is fed into the shingle cutting machine. After the shingles have been cut, they are
moved by roller conveyor to manual or automatic packaging equipment. They are then stacked
on pallets and transferred by fork lift to storage areas or waiting trucks (U.S. EPA, 1980).
As indicated previously, the primary POM emissions sources associated with
manufacturing asphalt roofing products are the asphalt air-blowing stills (and associated oil
knockout boxes) and the felt saturators (U.S. EPA, 1980). This was determined during
development of the NSPS for manufacturing asphalt roofing products. Additional potential POM
emission sources include the wet looper, the coater-mixer, the felt coater, the seal-down stripper,
and storage tanks for air-blown asphalt. Minor fugitive emissions are also possible from asphalt
flux and blown asphalt handling and transfer operations (U.S. EPA, 1980; Kelly, 1983;
Gerstle, 1974; Siebert et al., 1978).
4-304
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Emission Control Techniques-The asphalt roofing products NSPS established limits on
particulate emissions and opacity from saturators and blowing operations. Process selection and
control of process parameters have been promoted to minimize uncontrolled emissions, including
POM, from asphalt air-blowing stills, asphalt saturators, wet loopers, and coalers. Process
controls include the use of (U.S. EPA, 1980):
• Dip saturators rather than spray or spray-dip saturators;
• Vertical stills rather than horizontal stills;
• Asphalts that inherently produce low emissions;
• Higher flash point asphalts;
• Reduced temperatures in the asphalt saturant pan;
• Reduced asphalt storage temperatures; and
• Lower asphalt blowing temperatures.
Dip saturators have been installed for most new asphalt roofing line installations
in recent years, and this trend is expected to continue. Recent asphalt blowing still installations
have been almost exclusively of the vertical type because of the higher efficiency and lower
emissions. Vertical stills occupy less space and require no heating during oxidizing (if the
temperature of the incoming flux is above 400°F [204°C]). Vertical stills are expected to be
used in new installations equipped with stills and in most retrofit situations (U.S. EPA, 1980).
Asphalt fluxes with lower flash points and softening points tend to have higher
emissions of organics because these fluxes generally have been less severely cracked and contain
more low-boiling fractions. Many of these light ends can be emitted during blowing. Limiting
the minimum softening and flash points of asphalt flux should reduce the amount of
POM-containing fumes generated during blowing because less blowing is required to produce a
saturant or coating asphalt. Saturant and coating asphalts with high softening points should
reduce POM emissions from felt saturation and coating operations. However, producing the
4-305
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higher softening asphalt flux requires more blowing, which increases uncontrolled emissions
from the blowing operation (U.S. EPA, 1980).
Although these process-oriented emissions control measures are useful, emissions
capture equipment and add-on emissions control equipment are also necessary in new asphalt
roofing production facilities that are subject to the NSPS. The capture of potential POM
emissions from asphalt blowing stills, asphalt storage tanks, asphalt tank truck unloading, and the
coater-mixer can be and is being achieved in the industry by the use of enclosure systems around
the emissions operations. The enclosures are maintained under negative pressure, and the
contained emissions are ducted to control devices (U.S. EPA, 1980). Potential emissions from
the saturator, wet looper, and coater are generally collected by a single enclosure, by a canopy
type hood, or by an enclosure/hood combination. Typically applied controls for POM emission
sources in asphalt roofing plants are summarized in Table 4.6-1.
Emission Factors
Emission factors for POM from asphalt roofing manufacturing are available for
asphalt air-blowing stills and saturators (U.S. EPA, 1980). The data were gathered to support
development of the NSPS for the asphalt roofing industry, which focused on control of PM and
VOC, not individual toxic air pollutants. Because the blowing stills and saturators were
identified as significant sources of emissions, the pollutants emitted from these two points in the
manufacturing process were characterized more completely than were other emission points.
Hence, POM data are available for these two points only, and are presented in Table 4.6-2.
Moreover, some POM species were identified in samples, but the amounts present were not or
could not be quantified. The POM identified but not quantified are indicated in Table 4.6-2.
Other reports have presented estimates of total POM emissions, both controlled
and uncontrolled, from blowing stills, saturators, and other emission points (Gerstle, 1974;
Kelly, 1983; Hangebrauck et al., 1967; Siebert et al., 1978). Unfortunately, data are not available
to speciate the reported factors into individual POM emission factors. It is worth noting that the
reported factors for total POM emissions are highly variable, in part because of differences in
4-306
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TABLE 4.6-1. CONTROL DEVICES USED ON POM EMISSIONS SOURCES
IN ASPHALT ROOFING PLANTS
Emission Source Control Device
Saturator, wet looper (hot looper), and coater* Afterburner
High-velocity air filter
Electrostatic precipitator
Coater-mixerb High-velocity air filter
Asphalt blowing still Afterburner
Asphalt storage tanks0 Mist eliminator
"These sources usually share a common enclosure, and emissions are ducted to a common control
device.
'"Emissions from the coater-mixer are controlled at some plants by routing fumes to the control
device used for the saturator, wet looper, or coaler.
cSome plants control emissions from storage tanks with the same device used for processes listed
in A and then use a mist eliminator during periods when the roofing line is not operating
(e.g., weekends). Asphalt delivery can be accomplished via a closed system that vents emissions
to the control device used for the tanks.
Source: U.S. EPA, 1980.
4-307
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TABLE 4.6-2. PAH EMISSION FACTORS FOR ASPHALT ROOFING MANUFACTURING
SCC Number Emission Source Control Device Pollutant
3-05-001-01 Asphalt Blowing: Uncontrolled Anthracene/Phenanthrene
Saturant
Fluoranthene/Methylpyrene
Methylanthracenes
Methylchrysenes
3-05-001-01 Asphalt Blowing: Afterburner Anthracene/Phenanthrene
Saturant
•{*• Fluoranthene/Methylpyrene
^ Methylanthracenes
3-05-001-03 Felt Saturation: Uncontrolled Anthracene/Phenanthrene
Dipping Only
Fluoranthene/Methylpyrene
Methylanthracenes
Methylchrysenes
3-05-001-03 Felt Saturation: Afterburner Benz(a)anthracene/Chrysene
Dipping Only
Anthracene/Phenanthrene
Methylanthracenes
Methylchrysenes
Average Emission
Factor in Emission Factor
Ib/ton (kg/Mg) Rating
0.0049
(0.0024)a-b
0.0052
(0.0026)a'b
0.0134
(0.0067)a-b
0.0046
(0.0023)a-b
3.3E-05(1.6E-05)a>b
2.1E-05(l.lE-05)a'b
2.9E-05(1.4E-05)a'b
1.2E-04(6.2E-05)a'c'd
5.3E-05 (2.6E-05)a'c'd
3.2E-04(1.6E-04)a'Cld
2.9E-05(1.5E-05)a'c'd
l.lE-04(5.7E-05)a'c-e
3.4E-04(1.7E-04)a-c'e
5.7E-04 (2.8E-04)a'°'e
1.3E-04(6.3E-05)a-c>e
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.6-2. (Continued)
SCC Number
3-05-001-03
(continued)
Emission Source
Felt Saturation:
Dipping Only
Control Device Pollutant
ESP Anthracene/Phenanthrene
Fluoranthene/Methylpyrene
Methylanthracenes
Average Emission
Factor in
Ib/ton (kg/Mg)
4.8E-05 (2.4E-05)a'c'c
2.3E-05(1.2E-05)a'c'e
l.lE-04(5.5E-05)a-c-e
Emission Factor
Rating
D
D
D
"Anthracene, phenanthrene, methylanthracenes, fluoranthene, pyrene, methylpyrene, benz(c)phenanthrene, chrysene, benz(a)anthracene,
methylchrysenes, benzofluoranthenes, benzo(a)pyrene, benzo(e)pyrene, and perylene were detected in these emissions, but not all species
were quantified.
''Emission factors in Ib/ton (kg/Mg) of asphalt blown. Factors based on 1 facility.
cEmission factors in Ib/ton (kg/Mg) of asphalt roofing (e.g., shingles, rolls) produced.
dFactors based on 2 facilities.
eFactors based on 1 facility.
Source: U.S. EPA, 1980.
-------
sampling and analytical methodology. However, qualitatively the POM compounds identified in
the emission streams are very consistent.
The POM compounds identified in roofing source emissions were consistent
within a source type (e.g., saturators) and between different source types. Anthracene/
phenanthrene, methyl anthracenes, fluoranthene, pyrene, methyl pyrene, chrysene,
benz(a)anthracene, methyl chrysenes, benzofluoranthenes, benzo(a)pyrene, and benzo(e)pyrene
were identified in the emissions measurements of practically every source. In both controlled
and uncontrolled emissions of saturators and blowing stills, methyl anthracenes predominated.
Anthracene/phenanthrene and methyl pyrene/fluoranthene also repeatedly constituted significant
portions of total POM emissions. Generally, the three POM compound groups constituted 90 to
95 percent of total POM measured.
Source Locations
A list of all current facilities, as identified by the Asphalt Roofing Manufacturers
Association, is provided in Table 4.6-3 (Asphalt Roofing Manufacturers Association, 1994).
States containing a relatively significant number of roofing plants include California, Texas,
Ohio, and Alabama. These four states contain approximately 40 percent of the total number of
roofing facilities. The majority of all plants nationwide are located in urban as opposed to rural
areas.
4.6.2 Hot Mix Asphalt Production
Process Description
In the production of hot mix asphalt (also referred to as asphalt concrete),
aggregate is heated to eliminate moisture and then mixed with hot asphalt cement. The resulting
hot mixture is pliable and able to be compacted and smoothed. When it cools and hardens, hot
mix asphalt provides a waterproof and durable pavement for roads, driveways, parking lots, and
runways.
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TABLE 4.6-3. ASPHALT ROOFING MANUFACTURERS
Company
Roofing Plant Location
Allied-Signal, Inc.
Bird, Inc.
The Celotex Corporation
Certainteed Corporation
Elk Corporation of America
Fields Corporation
GAF Building Materials, Inc.
Gate Roofing Manufacturing, Inc.
Georgia-Pacific Corporation
Detroit, MI
Fairfield, AL
Iron ton, OH
Norwood, MA
Camden, AR
Fremont, CA
Birmingham, AL
Goldsboro, NC
Houston, TX
Lockland, OH
Perth Amboy, NJ
San Antonio, TX
Los Angeles, CA
Memphis, TN
Shakopee, MN
Oxford, NC
Milan, OH
Ennis, TX
Tuscaloosa, AL
Kent, WA
Tacoma, WA
Baltimore, MD
Dallas, TX
Erie, PA
Fontana, CA
Millis, MA
Minneapolis, MN
Mobile, AL
Mount Vernon, IN
Savannah, GA
Tampa, FL
Green Cove Springs, FL
Ardmore, OK
Daingerfield, TX
Franklin, OH
Hampton, GA
Quakertown, PA
4-311
(continued)
-------
TABLE 4.6-3. (Continued)
Company
Roofing Plant Location
Globe Building Materials
GS Roofing Products Company, Inc.
Herbert Malarkey Roofing Company
IKO Chicago, Inc.
IKO Production, Inc.
Koppers Industries, Inc.
Leatherback Industries
Lunday-Thagard Company
Manville Sales Corporation
Neste Oil Services
Whiting, IN
St. Paul, MN
Chester, WV
Charleston, SC
Ennis, TX
Little Rock, AR
Martinez, CA
Peachtree City, GA
Portland, OR
Shreveport, LA
Wilmington, CA
Portland, OR
Chicago, IL
Franklin, OH
Wilmington, DE
Birmingham, AL
Chicago, IL
Follensbee, WV
Houston, TX
Alburquerque, MM
Hollister, CA
South Gate, CA
Fort Worth, TX
Pittsburg, CA
Savannah, GA
Waukegan, IL
Belton, TX
Calexico, CA
Fresno, CA
Houston, TX
Long Beach, CA
Pittsburg, CA
Salt Lake City, UT
San Diego, CA
4-312
(continued)
-------
TABLE 4.6-3. (Continued)
Company
Roofing Plant Location
Owens-Corning Fiberglas Corporation
PABCO Roofing Products
TAMKO Asphalt Products, Inc.
TARCO, Inc.
U.S. Intec, Inc.
Atlanta, GA
Brookville, IN
Compton, CA
Denver, CO
Detroit, MI
Houston, TX
Irving, TX
Jacksonville, FL
Jessup, MD
Kearny, NJ
Medina, OH
Memphis, TN
Minneapolis, MN
Morehead City, NC
Oklahoma City, OK
Portland, OR
Richmond, CA
Tacoma, WA
Dallas, TX
Frederick, MD
Joplin, MO
Phillipsburg, KS
Tuscaloosa, AL
North Little Rock, AR
Belton, TX
Corvallis, OR
Monroe, GA
Source: Asphalt Roofing Manufacturers Association, 1994.
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There are three types of hot mix asphalt plants operating in the United States:
batch-mix, continuous-mix, and drum-mix. Batch-mix and continuous-mix plants separate the
aggregate drying process from the mixing of aggregate with asphalt cement. Drum-mix plants
combine these two processes. Production capacities for all three types of plants range from 40 to
600 tons (36 to 544 Mg) of hot mix per hour. Almost all plants in use are of either the batch-mix
or drum-mix type. Less than 0.5 percent of operating hot mix plants are of the continuous-mix
design (U.S. EPA, 1995). Over 80 percent of all hot mix asphalt production plants are mobile
units (U.S. EPA, 1985).
Aggregate, the basic raw material of hot mix asphalt, consists of any hard, inert
mineral material such as gravel, sand, or mineral filler. Aggregate typically comprises 90 to
95 percent by weight of the asphalt mixture. Because aggregate provides most of the
load-bearing properties of a pavement, the performance of the pavement depends on selection of
the proper aggregate.
Asphalt cement is used as the binding agent for aggregate. It prevents moisture
from penetrating the aggregate and acts as a cushioning agent. Typically, asphalt cement
constitutes 4 to 6 percent by weight of a hot mix asphalt mixture (U.S. EPA, 1985).
As with the asphalt flux used to produce asphalt roofing products, asphalt cement
is obtained from the distillation of crude oil. It is classified into grades under one of three
systems. The most commonly used system classifies asphalt cement based on its viscosity at
140°F (60°C). The more viscous the asphalt cement, the higher its numerical rating. An asphalt
cement of grade AC-40 is considered a hard asphalt (i.e., a viscosity of 4,000 grams per
centimeter per second [g/cm-s or poises]), and an asphalt cement of grade AC-2.5 is considered a
soft asphalt (i.e., a viscosity of 250 g/cm-s [poises]).
Several western states use a second grading system that measures viscosity of the
asphalt cement after a standard simulated aging period. This simulated aging period consists of
exposure to a temperature of 325°F (163°C) for 5 hours. Viscosity is measured at 140°F
4-314
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(60°C), with grades ranging from AR-1000 for a soft asphalt cement (1000 g/cm-s [poises]) to
AR-16000 for a hard asphalt cement (16,000 g/cm-s [poises]).
A third grading system is based on the penetration allowed by the asphalt cement.
Grade designation 40 to 50 means that a needle with a weight attached will penetrate the asphalt
cement 40 to 50 tenths of a millimeter under standard test conditions. The hard asphalt cements
have penetration ratings of 40 to 50, and the soft grades have penetration ratings of 200 to 300
(U.S. EPA, 1985).
The asphalt cement grade selected for different hot mix asphalts depends on the
type of pavement, climate, and type and amount of traffic expected. Generally, asphalt pavement
bearing heavy traffic in warm climates would require a harder asphalt cement than pavement
subject to either light traffic or cold climate conditions.
Another material that is used to a great extent in the production of new or virgin
hot mix asphalt is recycled asphalt pavement (RAP), which is pavement material that has been
removed from existing roadways. This RAP material is now used by virtually all companies in
their hot mix asphalt mixtures. The Surface Transportation Assistance Act of 1982 encourages
recycling by providing a 5 percent increase in Federal funds to State agencies that recycle asphalt
pavement. Rarely does the RAP comprise more than 60 percent by weight of the new asphalt
mixture. Twenty-five percent RAP is typical in batch plants, and 40 to 50 percent RAP mixtures
are typical in drum-mix plants (U.S. EPA, 1985).
Rejuvenating agents are sometimes used in hot mix asphalts using RAP to bring
the weathered and aged asphalt cement in the recycled mixture up to the specifications of the new
asphalt mixture. Usually, soft asphalt cement, specially prepared high-viscosity oil, or hard
asphalt cement blended with a low-viscosity oil are used as rejuvenating agents. The amount of
rejuvenating agent added depends on the properties of the RAP and the specifications for the hot
mix asphalt product.
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Sulfur has also been used on an experimental basis as a substitute for a portion of
the asphalt cement in hot mix asphalt mixtures. Asphalt cement/sulfur combination is better able
to bind with aggregate than is asphalt cement alone. Hot mix asphalt pavements containing the
asphalt cement/sulfur combination appear to be stronger and less susceptible to temperature
changes than those containing asphalt cement alone.
The use of sulfur is not competitive with asphalt cement in hot mix asphalt mixes
for several reasons, including environmental issues, worker objections (odor), and corrosion, all
of which result from emissions of hydrogen sulfide (H2S), sulfur dioxide (SO2), and elemental
sulfur (S). In addition, sulfur is almost twice as dense as asphalt cement. Consequently, to make
the use of sulfur economically feasible, the cost of sulfur must be less than half the cost of
asphalt cement (U.S. EPA, 1985).
Batch-Mix Process—The primary processes of a typical batch-mix hot mix asphalt facility are
illustrated in Figure 4.6.2-1. Aggregate of various sizes is stockpiled at the plant for easy access.
Aggregate is typically transported by front-end loader to separate cold feed bins and metered onto
a feeder conveyor belt through gates at the bottom of the bins. The aggregate is screened before
it is fed to the dryer to keep oversized material out of the mix.
The screened aggregate is then fed to a rotating dryer with a burner at its lower
(discharge) end that is fired with fuel oil, natural gas, or propane. The dryer removes moisture
from the aggregate and heats the aggregate to the proper mix temperature. Inside the dryer are
longitudinal flights (metal slats) that lift and tumble the aggregate, causing a curtain of material
to be exposed to the heated gas stream. This curtain of material provides greater heat transfer to
the aggregate than would occur if the aggregate tumbled along the bottom of the drum towards
the discharge end. Aggregate temperature at the discharge end of the dryer is about 300°F
(149°C). The amount of aggregate that a dryer can heat depends on the size of the drum, the size
of the burner, and the moisture content of the aggregate. As the amount of moisture to be
removed from the aggregate increases, the effective production capacity of the dryer decreases.
4-316
-------
RAP BIN & CONVEYOR
SECONDARY FINES
RETURN LINE
SECONDARY COLLECTOR
FINE AGGREGATE
STORAGE PILE
(SCC JOW02 OH
/iS*
^^^^t^^^£*^^^^^^^^^^^
COURSE AGGREGATE
CTDDAAC EMI E
.frviAK nwnK**^
STORAGE PILE
I6CC MK402-O3)
UJ
»—'
-J
ASPHALT CEMENT STORAGE HEATER
(SCC yOWXB 0«. -07. -M. 4M>
./'"* EirtwJonPolnta
j*^
I Proctu FugUvt EmlMtom
)opmOuttEmlHlont
Figure 4.6.2-1. General Process Flow Diagram for Batch Mix Asphalt Paving Plants
Source: U.S. EPA, 1995.
-------
Vibrating screens segregate the heated aggregate into bins according to size. A
weigh hopper meters the desired amount of the various sizes of aggregate into a pugmill mixer.
The pugmill typically mixes the aggregate for 15 seconds before hot asphalt cement from a
heated tank is sprayed into the pugmill. The pugmill thoroughly mixes the aggregate and hot
asphalt cement for 25 to 60 seconds. The finished hot mix asphalt is either directly loaded into
trucks or held in insulated and/or heated storage silos. Depending on the production
specifications, the temperature of the hot mix asphalt product mix can range from 225 to 350°F
(107 to 177°C) at the end of the production process.
When a hot mix containing RAP is produced, the aggregate is superheated
(compared to totally virgin hot mix asphalt production) to about 600°F (315°C) to ensure
sufficient heat transfer to the RAP when it is mixed with the virgin materials. The RAP material
may be added either to the pugmill mixer or at the discharge end of the dryer. Rarely is more
than 30 percent RAP used in batch plants for the production of hot mix asphalt.
Continuous-Mix Process--Continuous-mix plants are very similar in configuration to batch
plants. Continuous-mix plants have smaller hot bins (for holding the heated aggregate). Little
surge capacity is required of these bins because the aggregate is continuously metered and
transported to the mixer inlet by a conveyor belt. Asphalt cement is continuously added to the
aggregate at the inlet of the mixer. The aggregate and asphalt cement are mixed by the action of
rotating paddles while being conveyed through the mixer. An adjustable dam at the outlet end of
the mixer regulates the mixing time and also provides some surge capacity. The finished mix is
transported by a conveyor belt to either a storage silo or a surge bin (U.S. EPA, 1985).
Drum-Mix Process-Drum-mix plants dry the aggregate and mix it with the asphalt cement in the
same drum, eliminating the need for the extra conveyor belt, hot bins and screens, weigh hopper,
and pugmill used at batch-mix plants. The drum of a drum-mix plant is much like the dryer of a
batch plant, but it typically has more flights to increase veiling of the aggregate and improve
overall heat transfer. The burner in a drum-mix plant emits a much bushier flame than does the
burner in a batch plant. The bushier flame is designed to provide earlier and greater exposure of
4-318
-------
the virgin aggregate to the heat of the flame. This design also protects the asphalt cement, which
is injected away from the direct heat of the flame (U.S. EPA, 1985).
Initially, drum-mix plants were designed to be parallel flow, as depicted in
Figure 4.6.2-2. Recently, the counterflow drum mix plant design shown in Figure 4.6.2-3 has
become popular. The parallel flow drum-mix process is a continuous-mixing type process using
proportioning cold-feed controls for the process materials. Aggregate, which has been
proportioned by gradations, is introduced to the drum at the burner end. As the drum rotates, the
aggregates and the combustion products move in parallel toward the other end of the drum.
Liquid asphalt cement flow is controlled by a variable flow pump, which is electronically linked
to the virgin aggregate and RAP weigh scales. The asphalt cement, along with any RAP and PM
from collectors, is introduced in the mixing zone, midway down the drum in a lower temperature
zone. The mixture is discharged at the end of the drum and conveyed to a surge bin or storage
silos. The exhaust gases also exit the end of the drum and pass on to the collection system
(U.S. EPA, 1995).
In the counterflow drum-mix type plant, the material flow in the drum is opposite
or counterflow, to the direction of exhaust gases. In addition, the liquid asphalt cement mixing
zone is located behind the burner flame zone so as to remove the materials from direct contact
with hot exhaust gases. Liquid asphalt cement flow is controlled by a variable-flow pump and is
injected into the mixing zone along with any RAP and PM from primary and secondary
collectors (U.S. EPA, 1995).
Parallel flow drum-mixers have an advantage in that mixing in the discharge end
of the drum captures a substantial portion of the aggregate dust, therefore lowering the load on
the downstream collection equipment. For this reason, most parallel-flow drum-mixers are
followed only by primary collection equipment (usually a baghouse or venturi scrubber).
However, because the mixing of aggregate and liquid asphalt cement occurs in the hot
combustion product flow, organic emissions (gaseous and liquid aerosol) from parallel flow
drum-mixers may be greater than in other processes (U.S. EPA, 1995).
4-319
-------
»-. EXHAUST TO (
•*! ATMOSPHERE *
EXHAUST
u>
K>
O
SECONDARY FINES
RETURN LINE
FINE AGGREGATE
STORAGE PILE
(SCC 345402-03)
PARALLEL-FLOW
DRUM MIXER
(SCC 3-05-002-05)
CONVEYOR
SCALPING / COLO AGGREGATE
SCREEN _' - BINS
FEEDERS ,scc J4J402-04)
ASPHALT CEMENT HEATER
STORAGE (SCC 3-05-002-06. -07. -08. -09)
COURSE
AGGREGATE
STORAGE PILE
(SCC 3-05402-01)
LEGEND
/ Emtalon Points
©DudtdEirinioni
@ Prociw FugWvt Emission*
@ Opm Dint Eminlons
Figure 4.6.2-2. General Process Flow Diagram for Drum Mix Asphalt Paving Plants
Source: U.S. EPA, 1995.
-------
*.
N)
PRIMARY
COLLECTOR
RAP BIN & CONVEYOR
EXHAUSTTO
ATMOSPHERE
EXHAUST ,
FAN
LOADER
(SCC 345-00244)
SECONDARY
COLLECTOR
\SECONDARYFINES
RETURN LINE
FINE AGGREGATE
STORAGE PILE
(SCC 345402-03)
COURSE AGGREGATE
STORAGE PILE
(SCC 34540243)
COUNTER-FLOW
DRUM MIXER
(SCC 34540245)
CONVEYOR SCALPING
SCREEN
FEEDERS
COLD AGGREGATE BINS
(SCC 34540244)
ASPHALT CEMENT
STORAGE
HEATER
(SCC 34540246.47.49.09)
LEGEND
/ Emission Points
(P) Ducted Emissions
* Process Fugitive Emissions
I Open Dust Emissions
Figure 4.6.2-3. General Process Flow Diagram for Counter-flow Drum Mix Asphalt Paving Plants
Source: U.S. EPA, 1995.
-------
On the other hand, because the liquid asphalt cement, virgin aggregate, and RAP
are mixed in a zone removed from the exhaust gas stream, counterflow drum-mix plants will
likely have organic emissions (gaseous and liquid aerosol) that are lower than those at parallel
flow drum-mix plants. A counterflow drum-mix plant can normally process up to 50 percent
RAP with little or no observed effect upon emissions. Today's counterflow drum-mix plants are
designed for improved thermal efficiencies (U.S. EPA, 1995).
Of the 3,600 active hot mix asphalt plants in the United States, approximately
2,300 are batch-mix plants, 1,000 are parallel flow drum-mix plants, and 300 are counterflow
drum-mix plants. About 85 percent of plants being manufactured today are of the counterflow
drum-mix design; batch-mix plants and parallel flow drum-mix plants account for 10 percent and
5 percent, respectively (U.S. EPA, 1995).
One major advantage of drum-mix plants is that they can produce material
containing higher percentages of RAP than can batch-mix plants. The use of RAP significantly
reduces the amount of new (virgin) rock and asphalt cement needed to produce hot mix asphalt.
With the greater veiling of aggregate, drum-mix plants are more efficient than batch-mix plants
at transferring heat and achieving proper mixing of recycled asphalt and virgin materials
(U.S. EPA, 1985).
Emission Control Techniques-Emissions of POM from hot mix asphalt plants occur from the
aggregate rotary dryers (due to fuel combustion) and from the hot mix asphalt mixing vessels
(due to heating of the asphalt materials containing organics). Most plants employ some form of
mechanical collection, typically cyclones, to collect aggregate particle emissions from the rotary
dryers. These cyclones have a minimal collection efficiency for POM compounds because the
POM compounds are either in vapor form or predominantly exist on fine particles not captured
by the cyclones. In many installations, the recovered aggregate is recycled to the hot mix asphalt
process.
Overall, PM emissions from hot mix asphalt mixers are controlled by wet
scrubbers or baghouses (U.S. EPA, 1985). Again, the success of these control devices on POM
4-322
-------
emissions is dependent on the form of the POM (i.e., vapor versus paniculate and fine versus
coarse particle). In some installations, the exhaust stream of the rotary dryer cyclones is vented
to the baghouse or scrubber used for mixer emissions control (Khan et al., 1977). One early
reference indicated that for hot mix asphalt plants venting dry emissions to the mixer control
device, the POM compounds detected in the mixer control device emissions were predominantly
a function of the rotary dryer and not the mixer (Hangebrauck et al., 1967). Subsequent
investigations have not challenged this finding.
In any of the processes used to produce hot mix asphalt, fugitive POM emissions
may occur because of evaporative losses from asphalt handling and storage. Emissions of this
type would be highly variable. No examination of fugitive POM emissions from hot mix asphalt
plants could be found in the literature.
Emission Factors
Emissions from hot mix asphalt plants were reexamined recently for the purpose
of updating the information contained in EPA's Compilation of Air Pollutant Emission Factors,
commonly referred to as AP-42. Representative batch-mix and drum-mix plants (both parallel
flow and counterflow) were selected for testing. Emissions from hot oil heaters used to warm
stored asphalt concrete were also evaluated. Process emissions from hot mix plants include
criteria pollutants (i.e., PM, CO, CO2, NOX, SO2, and VOC) as a result of fuel combustion,
aggregate mixing and drying, and asphalt heating. Metal emissions are also of concern. POM
emissions are associated both with VOC and PM. The POM emission factors that were
developed for this AP-42 revision are provided in Tables 4.6-4,4.6-5, and 4.6-6
(U.S. EPA, 1995).
Previously, it had been thought that batch-mix plants tended to have a lower level
of total POM emissions than drum-mix plants (U.S. EPA, 1980). Such a conclusion cannot be
found in the more recent data. On the other hand, the newer reports indicate that counterflow
drum-mix plants can be expected to emit smaller quantities of organic compounds than parallel
4-323
-------
TABLE 4.6-4. PAH EMISSION FACTORS FOR BATCH-MIX HOT MIX ASPHALT PLANTS
SCC Number Emission Source Control Device Pollutant
3-05-002-01 Natural Gas-fired Fabric Filter Benz(a)anthracene
Dryer
B en zo(b)fl uoranthe ne
Benzo(k)fluoranthene
Chrysene
Acenaphthene
Acenaphthylene
Anthracene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Average Emission Factor in
Ib/ton (kg/Mg)a
4.5E-09
(2.3E-09)
4.5E-09
(2.3E-09)
2.4E-08
(1.2E-08)
6.1E-09
(3.1E-09)
1.2E-06
(6.2E-07)
8.6E-07
(4.3E-07)
3.1E-07
(1.5E-07)
3.1E-07
(1.6E-07)
2E-06
(9.8E-07)
4.2E-05
(2.1E-05)
3.3E-06
(1.6E-06)
Emission
Factor Rating ,
D
D
E
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.6-4. (Continued)
«i»
SCC Number Emission Source Control Device Pollutant
3-05-002-01 Natural Gas-fired Fabric Filter (continued) Pyrene
(continued) Dryer (continued)
2-Methylnaphthalene
3-05-002-01 Oil-fired Dryer Fabric Filter Fluoranthene
Naphthalene
Phenanthrene
Pyrene
2-Methylnaphthalene
Average Emission Factor in
Ib/ton (kg/Mg)a
6.2E-08
(3.1E-08)
7.7E-05
(3.8E-05)
2.4E-05
(1.2E-05)
4.5E-05
(2.2E-05)
3.7E-05
(1.8E-05)
5.5E-05
(2.7E-05)
6E-05
(3E-05)
Emission
Factor Rating
D
D
D
D
E
D
D
"Emission factors in Ib/ton (kg/Mg) of hot mix asphalt produced.
Source: U.S. EPA, 1995.
-------
TABLE 4.6-5. PAH EMISSION FACTORS FOR DRUM-MIX HOT MIX ASPHALT PLANTS
£
to
SCC Number Emission Source Control Device Pollutant
3-05-002-05 Natural Gas- or Fabric Filter Benz(a)anthracene
Propane-fired Dryer
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(g,h,i)perylene
Fluoranthene
Fluorene
Naphthalene
Average Emission Factor in
Ib/ton (kg/Mg)a
2.0E-07
(l.OE-07)
9.2E-09
(4.6E-09)
l.OE-07
(5.1E-08)
5.3E-08
(2.6E-08)
3.5E-07
(1.8E-07)
2.7E-09
(1.3E-09)
7.3E-09
(3.6E-09)
1.3E-06
(6.4E-07)
8.4E-06
(4.2E-06)
2.1E-07
(l.OE-07)
3.9E-08
(1.9E-08)
5.9E-07
(3.0E-07)
5.3E-06
(2.7E-06)
4.8E-05
(2.4E-05)
Emission
Factor Rating
D
D
D
D
D
E
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.6-5. (Continued)
SCC Number Emission Source Control Device Pollutant
3-05-002-05 Natural Gas- or Fabric Filter (continued) Phenanthrene
(continued) Propane-fired Dryer
(continued)
Pyrene
2-Chloronaphthalene
2-Methylnaphthalene
Benzo(e)pyrene
Perylene
3-05-002-05 Oil-fired Dryer Fabric Filter Acenaphthylene
Anthracene
Fluorene
Naphthalene
Phenanthrene
Pyrene
2-Methylnaphthalene
Average Emission Factor in
Ib/ton (kg/Mg)a
8.4E-06
(4.2E-06)
4.6E-07
(2.3E-07)
1.8E-06
(8.9E-07)
7.4E-05
(3.7E-05
l.OE-07
(5.2E-08)
1.2E-08
(6.2E-09)
2.2E-05
(1.1E-05)
3.6E-06
(1.8E-06)
1.7E-05
(8.5E-06)
3.1E-04
(1.6E-04)
5.5E-05
(2.8E-05)
3.0E-06
(1.5E-06)
1.7E-04
(8.5E-05)
Emission
Factor Rating
D
D
D
D
D
E
D
D
D
D
D
E
D
"Emission factors in Ib/ton (kg/Mg) of hot mix asphalt produced. Includes data from both parallel flow and counterflow dryers.
Source: U.S. EPA, 1995.
-------
TABLE 4.6-6. PAH EMISSION FACTORS FOR HOT MIX ASPHALT HOT OIL HEATERS
N)
00
SCC Number Emission Source Control Device Pollutant
3-05-002-08 Hot Oil Heater, No. 2 Fuel Oil Uncontrolled Benzo(b)fluoranthene
Acenaphthene
Acenaphthylene
Anthracene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
Average Emission
Factor in Ib/gal
(kg/l)a
l.OE-07
(1.2E-08)
5.3E-07
(6.4E-08)
2.0E-07
(2.4E-08)
1.8E-07
(2.2E-08)
4.4E-08
(5.3E-09)
3.2E-08
(3.8E-09)
1.7E-05
(2E-06)
4.9E-06
(5.9E-07)
3.2E-08
(3.8E-09)
Emission
Factor Rating
E
E
E
E
E
E
E
E
E
"Emission factors in Ib/gal (kg/1) of fuel consumed. Includes data from both parallel flow and counterflow dryers.
Source: U.S. EPA, 1995.
-------
flow plants. However, the available data are insufficient to accurately quantify the difference
(U.S. EPA, 1995).
The potential effect of the type of fuel used in the dryer, natural gas versus oil, can
be seen in the data in Table 4.6-5. Results from older tests are also presented (Fuchs et al., 1984;
Khan et al., 1977). These emission factors from older tests do not specify the fuel used in the
dryers; however, they indicate the potential effect different types of control devices may have on
emissions from drum-mix versus batch-mix plants.
The older tests also focused on the state in which the POM species exist when
emitted (i.e., the vapor phase or solid paniculate). The data indicate that drum-mix plants emit
POM primarily in the vapor phase, whereas POM is emitted mainly as PM from batch-mix
plants. The more recent testing did not attempt to confirm the findings regarding vapor phase
versus particulate POM emissions, but there is no indication that the results are no longer true.
Hence, it would seem that PM control techniques are not entirely suitable for controlling POM
from drum-mix plants, or that a combination of techniques to control both vapor phase and solid
emissions is called for at hot mix asphalt plants.
Source Locations
In 1983, there were approximately 2,150 companies operating an estimated
4,500 hot mix asphalt plants in the United States (U.S. EPA, 1985). Today, the number has
fallen to approximately 3,600 plants (U.S. EPA, 1995). Approximately 40 percent of these
companies operate only a single plant. Because plants must be located near the job site, plants
are concentrated in areas where the highway and road network is concentrated (U.S. EPA, 1985).
Additional information on the locations of individual hot mix asphalt facilities can best be
obtained by contacting the National Asphalt Pavement Association in Lanham, Maryland.
4-329
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SECTION 4.6 REFERENCES
Asphalt Roofing Manufacturers Association, letter to E. Paik, Radian Corporation. List of
Member Asphalt Roofing Manufacturing Plants and Locations. August 22,1994.
Fuchs, M.R. et al. Emission Test Report: T.J. Campbell Asphalt Concrete Plant. Oklahoma
City. Oklahoma. U.S. Environmental Protection Agency, Emissions Measurement Branch,
Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina.
EPA/EMB Report No. 83-ASP-4. May 1984.
Gerstle, R.W. Atmospheric Emissions From Asphalt Roofing Processes. U.S. Environmental
Protection Agency, Control Systems Laboratory, Research Triangle Park, North Carolina.
EPA-650/2-74-101. October 1974.
Hangebrauck, R.P. et al. Sources of Polynuclear Hydrocarbons in the Atmosphere. Public
Health Service, U.S. Department of Health, Education, and Welfare, Cincinnati, Ohio. Public
Health Service Report No. AP-33. pp. 27-28. 1967.
Kelly, M.E. Sources and Emissions of Polycvclic Organic Matter. U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina. EPA-450/5-83-010b.
pp. 5-62 to 5-68. 1983.
Khan, Z.X. et al. "Polycyclic Organic Material Emissions from Asphalt Hot Mix Plants." Paper
presented at the 70th Annual Meeting of the Air Pollution Control Association, Toronto, Ontario,
Canada. Paper No. 77-16.4. June 20-24, 1977.
Siebert, P.C. et al. Preliminary Assessment of the Sources. Control and Population Exposure to
Airborne Polycyclic Organic Matter (POM) as Indicated by Benzo(a)pyrene (BaP). Prepared for
U.S. Environmental Protection Agency, Pollutant Strategies Branch, Office of Air Quality
Planning and Standards, Research Triangle Park, North Carolina. EPA Contract No.
68-02-2836. pp. 72-78. November 1978.
U.S. Environmental Protection Agency. Compilation of Air Pollutant Emission Factors.
Volume I: Stationary Point and Area Sources. AP-42, Fifth Edition. Office of Air Quality
Planning and Standards, Research Triangle Park, North Carolina, pp. 11.1-1 to 11.1-5 and
11.2-1 to 11.2-5. 1995.
U.S. Environmental Protection Agency. Second Review of NSPS for Asphalt Concrete Plants.
Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina.
EPA-450/3-85-024. October 1985.
U.S. Environmental Protection Agency. Asphalt Roofing Manufacturing Industry Background
Information Document for Proposed Standards. Office of Air Quality Planning and Standards,
Research Triangle Park, North Carolina. EPA-450/3-80-021a. June 1980.
4-330
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4.7 COKE PRODUCTION
The coke production source category consists of the processes used to produce
coke from coal and the recovery and treatment of byproduct gases from the coking process to
generate secondary products such as crude tars, light oil, and ammonia.
Metallurgical coke is used in iron and steel industry processes (primarily in blast
furnaces) to reduce iron ore to iron. Over 90 percent of total coke production is dedicated to
blast furnace operations. Foundry coke comprises most of the balance and is used in foundry
furnaces for melting metal and in the preparation of molds. Foundry coke production uses a
different blend of coking coals, longer cooking times, and lower coking temperatures relative to
those used for metallurgical coke.
Most coke plants are colocated with iron and steel production facilities, and the
demand for coke generally corresponds to the production of iron and steel. There has been a
steady decline in the number of coke plants over the past several years for many reasons,
including a decline in the demand for iron/steel, increased production of steel by mini-mills
(electric arc furnaces that do not use coke), and the lowering of the coke:iron ratio used in the
blast furnace (e.g., increased use of pulverized coal injection). There were 28 coke plants
operating in the U.S. in 1992. Most coke is produced in the U.S. using the "byproduct" process,
and one plant uses a "nonrecovery" process (U.S. EPA, 1995).
The coking industry is classified into two general sectors, furnace plants and
merchant producers. Furnace plants are owned by or affiliated with iron- and steel-producing
companies that produce coke primarily for consumption in their own blast furnaces, although
some furnace plants also engage in intercompany sales with steel firms with excesses or deficits
in coke capacity. On the other hand, independent merchant plants produce coke for sale on the
open market and are typically owned by chemical and coal firms. These plants sell most of their
products to other companies engaged in blast furnace, foundry, and nonferrous smelting
operations. In a recent Federal rulemaking, merchant plants are now referred to as "foundry coke
producers" (57 FR 57534). In 1984, furnace plants accounted for about 92 percent of the total
4-331
-------
coke production, and foundry coke producers accounted for the remaining 8 percent, a
distribution that has not changed significantly (U.S. EPA, 1987).
Over 10,000 constituents have been identified in coke oven emissions, a
yellow-brown gas evolved during coking. These constituents include organic and inorganic
particulate matter, VOC, and gases such as H2S, SO2, NOX, NH3, CO, and others. Many of the
volatile components of coke oven gas are identified as HAPs in the 1990 Clean Air Act
Amendments. The EPA listed coke oven emissions themselves as a HAP as early as 1984.
Because of the variability in composition, the thousands of components of organic particulate
matter in coke oven emissions, including POM, have been consolidated for measurement as a
single quantity called benzene soluble organic (BSO). The compounds that comprise BSO are
high molecular weight organics that can be collected and dissolved in benzene and that remain
after the benzene is evaporated off the sample. In general, BSO is composed of compounds
having 16 or more carbon atoms. Coke oven gas contains measurable amounts of the POMs
listed in Table 4.7-1, and can be emitted from points throughout the entire coking process. The
POM and other aromatics in coke oven emissions are a primary health concern and the reason
why the coke production source category has been investigated for regulation for more than a
decade. Federal rulemakings target the emissions from each of the four main operations in the
byproduct coking process: (1) coal preparation and charging, (2) thermal distillation of coal
(i.e., coking), (3) handling of the finished coke product, and (4) recovery of coking byproducts.
A typical coke oven battery is shown in Figure 4.7-1. A generalized process flow diagram for
these operations is shown in Figure 4.7-2 (U.S. EPA, 1987).
The first Federal rule to address coke ovens was a NESHAP promulgated in 1989
targeting the benzene in the emissions from the fourth operation in the coke production cycle,
coke byproduct recovery. However, the techniques specified in this standard for controlling
benzene emissions also enable the control of the other coke oven gas constituents, namely POM,
as well. The next NESHAP to address coke oven emissions was finalized in 1993 and was one
of the first standards to be promulgated pursuant to Section 112(d) of the 1990 Clean Air Act.
Control of coke oven emissions was explicitly required by the 1990 Clean Air Act Amendments,
4-332
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TABLE 4.7-1. POM CONSTITUENTS IDENTIFIED IN COKE OVEN GAS
Compound
Percent of BSOa
Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j+k)fluoranthene
Chrysene/Triphenylene
Dibenz(a,h)anthracene
Indeno( 1,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
1 -Methylnaphthalene
2-Methylnaphthalene
2-Phenylnaphthalene
4H-Benzo(def)carbazole
4H-Cyclopenta(def)chrysene isomers
4H-Cyclopenta(def)phenanthrene
Aceanthrylene
Acephenanthrylene
Acridine
Anthanthrene
Azafluoranthene/Azapyrene
1.91
1.38
1.71
1.22
2.04
0.16
0.65
1.18
5.70
3.42
0.61
6.23
3.91
20b
13.6
4.28
3.01
6.76
0.29
0.29
0.45
0.57
0.20
0.24
0.29
0.24
0.04
(continued)
4-333
-------
TABLE 4.7-1. (Continued)
Compound
Percent of BSO
Benz(c)acridine
Benzo(a)fluoranthene
Benzo(a)fluorene
Benzo(b)fluorene
Benzo(c)phenanthrene
Benzo(e)pyrene
Benzo(ghi)fluoranthene
Benzo(b)chrysene
Benzo(b)naphtho(l ,2-d)thiophene
Benzo(b)naphtho(2, l-d)thiophene
Benzo(b)naphtho(2,3-d)thiophene
Benzocarbazoles
Benzonapthofurans
Binaphthyls
Biphenyl
Carbazole
Coronene
Cyclopenta(cd)pyrene
Dibenz(a,j)anthracene
Dibenzofuran
Dibenzothiophene
Dimethylfluorenes/Trimethyldibenzofurans
Di- and trimethylnaphthalenes
Dimethylphenanthrenes/Anthracenes
Indeno(7,1,2,3-cdef)chrysene
Methyl- and dimethyldibenzofurans
Methylacenaphthylenes
0.33
0.33
0.37
0.24
0.20
1.30
0.24
0.08
0.24
0.57
0.24
0.65
0.24
0.49
1.51
0.57
0.08
0.12
0.16
5.30
0.81
0.12
6.60
0.45
0.16
2.04
1.18
(continued)
4-334
-------
TABLE 4-7.1. (Continued)
Compound Percent of BSO
Methylbenzfluoranthenes/Methylbenzpyrenes 2.16
Methylbenzfluorenes/Dimethylfluoranthenes/Pyrenes 0.41
Methylbenzoquinolines 0.49
Methylbenzothiophenes 0.41
Methylbinaphthyls 0.37
Methylbiphenyls 1.22
Methylcarbazoles 0.12
Methylchrysenes/Benz(a)anthracenes 0.57
Methylfluoranthenes 0.12
Methylfluorenes 2.81
Methylphenanthrenes/Methylanthracenes 2.28
Methylphenylnaphthalene 0.08
Methylpyrenes 0.12
Naphthoquinolines 0.53
Napthacene 0.37
Perylene 0.37
Phenanthridine 0.45
Phenanthro(4,5-bcd)thiophene 0.29
Picene 0.08
Quinoline 0.20
POM > MW 302 0.94
aBSO - Benzene soluble organics.
Naphthalene is not measured as a BSO. The percentage listed reflects the ratio of naphthalene
emissions to BSO emissions (0.2:1). (Source: U.S. EPA, 1995).
Source: Kirtonet al., 1991.
4-335
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OJ
o\
Coal storage
bunker t
•w Transfer
2^' lower Coal conveyor
Barge unloader
Coal barges
Coal charging
/'(larry) car
Coke quenching
station
Quenched
coke
Coke screening
& car loading station
Figure 4.7-1. View of a Typical Coke Production Plant
Source: IARC, 1984.
-------
RIVER
u>
Ui
CZHID-O'
GAS FOR UNDERFUUNG COKE OVENS
FOR FURTHER
PROCESSING
OR FOR FUEL
HYDROGEN
SULFIDE
SCRUBBER
SODIUM PHENOLATE
FOR FURTHER
PROCESSING
». FROM STRIPPER
»— TO STRIPPER
NAPHTHALENE
Figure 4.7-2. Flow Sheet Showing the Major Steps in the Byproduct Coking Process
Source: U.S. EPA, 1987.
-------
and the 1993 rule established MACT for coke oven emissions during the initial charging
operation and from door and topside leaks during the second operation, coking. A third rule
scheduled to be implemented by the year 2000 will address coke oven emissions from the third
operation, product handling after the coking cycle is finished, which includes pushing and
quenching. This third rule may also target leaks of coke oven gas into combustion stacks during
the coking operation, where they can be vented uncontrolled to the atmosphere along with the
combustion exhaust. Another MACT standard is also planned for the year 2000 to address the
coke byproduct recovery operation again if it is determined that the original 1989 standard needs
to be augmented.
Because the 1990, Clean Air Act Amendments specifically required the
development of regulations governing coke oven emissions, coke ovens were among the first to
be included on the initial list of source categories for which Section 112(d) standards will be
developed. Hence, the discussion in this section is organized according to the three MACT
standards that have been promulgated or are planned to control coke oven emissions and the
POM they contain.
4.7.1 Coke Ovens: Charging. Door and Topside Leaks
Process Description
As shown in Figure 4.7-1, the initial operation in the byproduct coking process is
coal preparation and charging. The large majority of POM emissions occur during the charging
operation and the subsequent coking operation. Hence, the 1993 MACT standard for coke ovens
targeted these two operations and their emission points.
The coal that is charged to a byproduct coke oven is usually a blend of two or
more low, medium, or high volatile content coals that are generally low in sulfur and ash.
Blending is required to control the properties of the resulting coke and to optimize the quality
and quantity of coke byproducts. Blending may also help avoid the expansion exhibited by some
types of coal; this expansion may cause excessive pressure on the oven walls during coking and
4-338
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cracking operations, allowing coke oven gas to escape and be emitted from combustion stacks
(U.S. EPA, 1987).
Coal is usually received on railroad cars or barges. Conveyor belts transfer the
coal as needed from the barges or from a coal storage pile to mixing bins where the various types
of coal are stored. The coal is transferred from the mixing bins to a crusher where it is
pulverized to a preselected size between 0.006 to 0.13 inch (0.15 to 3.2 mm). The desired size
depends on the response of the coal to coking reactions and the ultimate coke strength that is
required.
The pulverized coal is then mixed and blended. Sometimes water and oil are
added to control the bulk density of the mixture. The prepared coal mixture is transported to coal
storage bunkers on the coke oven batteries (a battery is a group of byproduct coke ovens
connected by common walls). A weighed amount or volume of prepared coal is discharged from
the bunker into a larry car, a vehicle driven by electric motors that travels the length of the
battery top on a wide gauge railroad track. The larry car is positioned over the empty, hot oven,
the lids on the charging ports are removed, and the coal is discharged from the hoppers of the
larry car through discharge chutes. The flow rate from the hoppers to the oven can be controlled
by gravity, a rotary table, or screw feeders (U.S. EPA, 1987). To minimize the escape of gases
from the oven during charging, steam aspiration is used at most plants to draw gases from the
space above the charged coal into the collecting main (U.S. EPA, 1995).
Peaks of coal form directly under the charging ports as the oven is filled. These
peaks are leveled by a steel bar that is cantilevered from the pusher machine through an opening
called the chuck door on the pusher side of the battery. This leveling process provides a clear
vapor space and exit tunnel for the gases that are evolved during coking to flow to the standpipes,
which aids the uniform coking of the coal. After filling, the chuck door and the topside charging
ports are closed (U.S. EPA, 1987).
The next step in the process is the thermal distillation (i.e., coking) of coal in
which volatile components are driven off, leaving a strong matrix of the nonvolatile, high-carbon
4-339
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components that is termed coke. Coking takes place in coke oven batteries consisting of 20 to
100 adjacent ovens with integral flues. Coke oven heating systems fall into two general classes,
underjet and gun-flue. In the underjet heating system, the flue gas is introduced into each flue
from piping in the basement of the battery. The gas flow to each flue can be metered and
controlled. The gun-flue heating system introduces the gas through a horizontal gas duct
extending the length of each wall slightly below the floorline of each oven. Short ducts lead
upward to a nozzle brick at the bottom of each of the vertical flues in an oven (U.S. EPA, 1987).
Heat for the coking operation is provided by a regenerative combustion system
located below the ovens. Because the combustion flue gas contains a significant amount of
process heat, two heat regenerators are used for recovery. These regenerators are located below
each oven, one for combustion air and one for the combustion waste gas. The flow is alternated
between the two at about 30 minute intervals. Hence, coke ovens can be likened to chemical
retorts in that they are both batch-operated, fitted with exhaust flues (standpipes), and function
without the addition of any reagent.
After the ovens are filled, coking proceeds for 15 to 18 hours to produce
"furnace"coke used to convert iron ore to iron in blast furnaces. More time, 25 to 30 hours, is
required to produce "foundry" coke, a higher quality type of coke (i.e., higher carbon-containing)
used in metal foundries. The coking time is determined by the coal mixture, moisture content of
the coal, rate of underfiring, and the desired properties of the coke. The coking temperatures
generally range from 1,650 to 2,000°F (900 to 1,100°C) and are kept on the high side of the
range to produce blast furnace coke. Air is prevented from leaking into the ovens by maintaining
a positive back pressure of about 0.4 in (10 mm) H2O. The gases and hydrocarbons that are
evolved during thermal distillation are removed through the offtake main and sent to the coke
byproduct recovery plant (which is described in Section 4.7.3) (U.S. EPA, 1987).
The operation of each oven in the battery is cyclic, but the batteries usually
contain a sufficiently large number of ovens (an average of 60) so that the volume of byproduct
gas evolved and fed to the byproduct recovery plant is essentially continuous. The individual
ovens are charged and discharged at approximately equal time intervals during the coking cycle.
4-340
-------
The resultant constant flow of evolved gases from all the ovens in a battery helps to maintain a
balance of pressure in the flues, collecting main, and stack. All of the ovens are fired
continuously at a constant rate, irrespective of the coking cycle of a particular oven's stage. If
damage to the refractory occurs in inaccessible locations through overheating or expansion of
coal, repairs may be extremely difficult. A cooldown takes from 5 to 7 weeks, so a battery
shutdown is undertaken only as a last alternative (U.S. EPA, 1987).
From the start of the charging operation, POM can be emitted while the hot oven
is being filled with coal. Moist coal contacts the hot oven floor and walls and, as a result, the
release of volatile components begins immediately. During coking, as volatiles are being driven
from the coal, POM can be emitted from leaking side doors and various leaking topside points
such as charging port lids and the offtake system that ducts the offgases to the collecting main(s).
The techniques and practices that have been developed to control these emissions are listed in
Table 4.7-2 (U.S. EPA, 1987).
Staged charging involves pouring coal into the ovens so that an exit space for the
generated gases is constantly maintained. The hoppers delivering the coal are discharged such
that emissions are contained in the ovens and collecting mains by steam aspiration. Generally, a
maximum of two hoppers are discharging at the same time. In sequential charging, to shorten the
charging time, the first hoppers are still discharging when subsequent hoppers begin discharging
coal. In sequential charging, as with staged charging, the coke ovens are under aspiration. In the
use of wet scrubbers on larry cars, the emissions are contained by hoods or shrouds connected to
scrubbers that are lowered over the charging ports.
To control leaks from the side doors, the doors can be sealed before the coking
process begins. Some doors are designed with a flexible metal band or rigid knife edge as a seal.
The seal is formed by condensation of escaping tars on the metal edge of the door. Doors can
also be sealed by hand by troweling a mixture called "luting"(a slurry mixture of clay, coal, and
other materials) into the opening between the coke oven door and door frame. Luting mixtures
are generally prepared by plant personnel according to formulas developed by each plant. The
consistency (thickness) of the mixture is adjusted to suit different applications.
4-341
-------
TABLE 4.7-2. TECHNIQUES TO CONTROL POM EMISSIONS FROM
EMISSION POINTS AT BYPRODUCT COKE PLANTS
Emission Point
Control Technique
Charging Operation
Door Leaks
Stage Charging
Sequential Charging
Scrubber Systems Mounted on Larry Cars
Oven Door Seal Technology
Pressure Differential Devices
Hoods and Sheds Over Doors
Operating and Maintenance Procedures
Topside Leaks (Charging Port Lids and Standpipes) Operating and Maintenance Procedures
Pushing
Quenching
Battery Stacks
Hooded, Mobile Scrubber Cars
Hoods and Sheds Over Doors
Traveling Hoods Connected to Fixed Control Device
Baffles in Quench Tower
Use of Clean Quench Water Only
Dry Quenching
Operating and Maintenance Procedures
Containment and Control Devices
Source: Kelly, 1983.
4-342
-------
Small cracks and defects in either type of seal can allow pollutants to escape from
the coke oven early in the cycle. The magnitude of the leak is determined by the size of the
opening, the pressure drop between the oven and the atmosphere, and the composition of the
emissions. A pressure differential control device can be used to reduce or reverse the pressure
differential across any defects in the door seal. These systems either provide a channel to permit
gases that evolve at the bottom of the oven to escape to the collecting main, or the systems
provide external pressure on the seal through the use of steam or inert gases.
Oven door emissions also can be reduced by collecting the leaking gases and
particulates, and subsequently removing these pollutants from the air stream. A suction hood or
shed above each door with a wet electrostatic precipitator for fume removal is an example of this
type of system.
Emission control levels for coke oven charging, door leaks, lid leaks, and offtake
leaks are categorized as uncontrolled, pre-NESHAP controls, and post-NESHAP controls.
Uncontrolled pertains to the control level that characterized coke ovens up to the 1980's;
pre-NESHAP controls pertain to the level of control prior to the effective data of the National
Emission Standard for Hazardous Air Pollutants (NESHAP) for coke ovens (40 CFR Part 63,
Subpart L); and post-NESHAP controls refer to the level of control required by the NESHAP.
Table 4.7-3 summarizes these control levels (U.S. EPA, 1995).
Other control techniques rely on operating and maintenance procedures rather
than only hardware. Operating procedures for emission reduction could include changes in the
oven cycle times and temperatures; the amount and placement of each charge; and any
adjustments of the end-door while the oven is on line. Maintenance procedures include routine
inspection, replacement, and repair of control devices and doors.
Topside leaks occurring from rims of charging ports and standpipe leaks on the
top of the coke oven can be controlled primarily by proper maintenance and operating procedures
that include:
• Replacement of warped lids;
4-343
-------
TABLE 4.7-3. EMISSION CONTROL LEVELS FOR CHARGING AND DOOR, LID,
AND OFFTAKE LEAKSa
Source
Uncontrolled
Pre-NESHAP Controls
Post-NESHAP
Controls
Charging
(SCC-3-03-003-02)
Door Leaks
(SCC 3-03-003-08)
3 to 5 minutes/charge
29 to 70 percent leaking
(average 50 percent)
Stage charging,
25 to 30 seconds/charge,
44 g BSO/charge
10 percent leaking
Stage charging,
steam
aspiration,
10 seconds/charge,
5 g BSO/charge
4 percent leaking
Lid Leaks
(SCC 3-03-003-14)
Offtake Leaks
(SCC 3-03-003-14)
25 percent leaking
50 percent leaking
3.5 percent leaking
6.5 percent leaking
0.3 percent leaking
2.0 percent leaking
aSCC=Source Classification Code.
4-344
-------
• Cleaning carbon deposits or other obstructions from the mating
surfaces of lids or their seats;
• Patching or replacing cracked standpipes;
• Sealing lids with lute after a charge or whenever necessary; and
• Sealing cracks at the base of a standpipe with lute.
Emission Factors
Limited emission factor data exist for individual POM species emissions from the
different operations in the byproduct coking process. The quantity and composition of emissions
from coking processes are highly variable because coking conditions can vary widely from plant
to plant and within the same plant from process to process. Coal composition and moisture
content vary widely, and these process variables can have a significant bearing on emissions.
Coking times and temperatures can also be varied so as to have marked impacts on potential
POM emissions. The fugitive nature of the majority of coking process emissions complicates
emissions control and increases the potential for widely varying emission estimates.
Emission factors for BSO from different points in coke ovens are listed in
Table 4.7-4. The emission factors for charging, door leaks, lid leaks, and offtake leaks are listed
for each of the control scenaries (uncontrolled, pre-NESHAP, post-NESHAP) summarized
previously in Table 4.7-3. With the exeception of the factors for uncontrolled charging and
uncontrolled door leaks, the emission factors for leaks and charging given in Table 4.7-4 are
based on an average or typical battery. These emission factors may be useful if site-specific
information (other than capacity) is not available for the battery. The preferred approach for a
specific battery is to use the actual number of emission points on the battery and historical data
for control of visible emissions, such as the annual average percent of the doors that leak.
The distribution of BSO emissions from the charging, door, and topside leaks as a
percentage of emissions from all coke oven emissions prior to the passage of the 1993 MACT
standard was estimated to be as follows:
4-345
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TABLE 4.7-4. BSO EMISSION FACTORS FOR COKE OVEN SOURCES*
BSOb
Source
kg/Mg
Ib/ton
Charging0
(SCC 3-03-003-02)
Uncontrolled
Pre-NESHAP controls
Post-NESHAP controls
DoorLeaksc'd
(SCC-3-03-003-08)
Uncontrolled
Pre-NESHAP controls
Post-NESHAP controls
Lid Leaksc-d
(SCC 3-03-003-14)
Uncontrolled
Pre-NESHAP controls
Post-NESHAP controls
Offtake leaksc-d
(SCC 3-03-003-14)
Uncontrolled
Pre-NESHAP controls
Post-NESHAP controls
Coke Pushing6
(SCC 3-03-003-03)
0.44
0.0027
0.00030
0.28
0.011
0.0044
0.025
0.0036
0.00030
0.025
0.0033
0.0010
0.008-0.017
0.88
0.0053
0.00060
0.55
0.022
0.0088
0.050
0.0071
0.00060
0.050
0.0066
0.0020
0.016-0.034
Coke Quenching6
(SCC 3-03-003-04)
0.011-2.8
0.022-5.6
Battery Stacks6
(SCC 3-03-003-17)
0.0016
0.0032
"Emission factors in Ib/ton (kg/Mg) of coal charged. SCC = Source Classification Code.
bBSO = benzene soluble organics.
'Source: U.S. EPA, 1995.
dFor site-specific estimates based on the average number of leaks, estimate BSO as follows:
Average number of doors leaking x 0.05 = door leak emission rate, kg/hr;
Average number of lids leaking x 0.023 = lid leak emission rate, kg/hr; and
Average number of offtakes leaking x 0.023 = offtake leak emission rate, kg/hr.
eSource: Trenholm and Beck, 1978.
4-346
-------
• About 5 percent from oven charging;
• About 81 percent from coke oven door leaks; and
• About 14 percent from topside point leaks.
These percentages reflect both the amount of total coke oven emissions expected from each type
of point and the BSO content of the emissions from each type of point. For instance, there is a
lower quantity of BSO (and hence POM) in charging emissions than in those from leaks, and
more coke oven emissions in general are associated with door leaks than the other two points
(57 FR 57534).
Similarly, benzo(a)pyrene has also been measured as a surrogate for total POM.
Reported measurements of benzo(a)pyrene from the three different emission points also vary by
orders of magnitude for different emission tests. The variability in measurements is again due to
the time into the coking cycle and temperature when sampling occurred, type of coal, analytical
techniques, or other differences between batteries. However, tests find the level of
benzo(a)pyrene in coke oven emissions overall is generally 1 percent of measured BSO
(U.S. EPA, 1987).
Emission factors for POM from charging, door, and topside leaks are given in
Table 4.7-5. The emission factors for individual PAHs including benzo(a)pyrene were derived
from the BSO emission factors reported in Table 4.7-4. Only a few researchers have attempted
to quantify the individual components in coke oven gas, and no attempt to speciate BSO
contained in coke oven gas could be found. A thorough analysis of organic matter in coke oven
emissions was reported by Kirton et al., 1991. The analysis included all organics containing six
and more carbons and their percentage contribution to the total organic content.
Using the information that BSO represents roughly the organic compounds
containing 16 or more carbons and benzo(a)pyrene represents one percent of BSO in general, the
speciation profile of BSO shown in Table 4.7-1 was developed from the Kirton et al. report.
Individual PAH emission factors were calculated by multiplying the BSO emission factors
4-347
-------
TABLE 4.7-5. POM EMISSION FACTORS FOR COKE OVENS: CHARGING, DOOR, LID AND OFFTAKE LEAKS
jx
li)
CO
SCC Number Emission Source Control Device Pollutant
3-03-003-02 Oven Charging- Uncontrolled Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j+k)fluoranthene
Chrysene/
Triphenylene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Emission Factor
in Ib/ton
(kg/Mg)a
1.68E-02
(8.40E-03)
1.21E-02
(6.07E-03)
1.50E-02
(7.52E-03)
1.07E-02
(5.37E-03)
1.80E-02
(8.98E-03)
1.41E-03
(7.04E-04)
5.72E-03
(2.86E-03)
1.04E-02
(5.19E-03)
5.02E-02
(2.51E-02)
3.01E-02
(1.50E-02)
5.37E-03
(2.68E-03)
5.48E-02
(2.74E-02)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
SCC Number Emission Source Control Device Pollutant
3-03-003-02 Oven Charging Uncontrolled Fluorene
(continued) (continued) (continued)
Naphthalene
Phenanthrene
Pyrene
1 -Methylnaphthalene
2-Methylnaphthalene
Benzo(e)pyrene
Biphenyl
Di- and Trimethylnaphthalenes
Dibenzofuran
Methyl- and
Dimethyldibenzofurans
Methylacenaphthylenes
Emission Factor
in Ib/ton
(kg/Mg)a
3.44E-02
(1.72E-02)
1.76E-01
(8.80E-02)
1.20E-01
(5.98E-02)
3.77E-02
(1.88E-02)
2.73E-02
(1.36E-02)
5.95E-02
(2.97E-02)
1.14E-02
(5.72E-03)
1.33E-02
(6.64E-03)
5.81E-02
(2.90E-02)
4.66E-02
(2.33E-02)
1.80E-02
(8.98E-03)
1.04E-02
(5.19E-03)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
u>
U»
o
SCC Number Emission Source Control Device Pollutant
3-03-003-02 Oven Charging Uncontrolled Methylbenzfluoranthenes/
(continued) (continued) (continued) Methylbenzpyrene
Methylbiphenyls
Methylfluorenes
Methylphenanthrenes/
Methylanthracenes
3-03-003-02 Oven Charging Pre-NESHAP Controls Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j+k)fluoranthene
Chrysene/
Triphenylene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Emission Factor
in Ib/ton
-------
TABLE 4.7-5. (Continued)
U)
SCC Number Emission Source Control Device Pollutant
3-03-003-02 Oven Charging Pre-NESHAP Controls Acenaphthylene
(continued) (continued) (continued)
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
1 -Methylnaphthalene
2-Methylnaphthalene
Benzo(e)pyrene
Biphenyl
Emission Factor
in Ib/ton
(kg/Mg)a
3.02E-04
(1.54E-04)
1.81E-04
(9.23E-05)
3.23E-05
(1.65E-05)
3.30E-04
(1.68E-04)
2.07E-04
(1.06E-04)
1.06E-03
(5.40E-04)
7.21E-04
(3.67E-04)
2.27E-04
(1.16E-04)
1.64E-04
(8.37E-05)
3.58E-04
(1.83E-04)
6.89E-05
(3.51E-05)
8.00E-05
(4.08E-05)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
SCC Number Emission Source Control Device Pollutant
3-03-003-02 Oven Charging Pre-NESHAP Controls Di- and
(continued) (continued) (continued) Trimethylnaphthalenes
Dibenzofuran
Methyl- and
Dimethyldibenzofurans
Methylacenaphthylenes
Methylbenzfluoranthenes/
Methylbenzpyrenes
Methylbiphenyls
Methylfluorenes
Methylphenanthrenes/
Methylanthracenes
3-03-003-02 Oven Charging Post-NESHAP Controls Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j+k)fluoranthene
Emission Factor
in Ib/ton
(kg/Mg)1
3.50E-04
(1.78E-04)
2.81E-04
(1.43E-04)
1.08E-04
(5.51E-05)
6.25E-05
(3.19E-05)
1.21E-04
(6.16E-05)
6.47E-05
(3.29E-05)
1.49E-04
(7.59E-05)
1.21E-04
(6.16E-05)
1.15E-05
(5.73E-06)
8.28E-06
(4.14E-06)
1.03E-05
(5.13E-06)
7.32E-06
(3.66E-06)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
U)
Lft
SCC Number Emission Source Control Device Pollutant
3-03-003-02 Oven Charging Post-NESHAP Controls Chrysene/
(continued) (continued) (continued) Triphenylene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
Emission Factor
in Ib/ton
(kg/Mg)a
1.22E-05
(6.12E-06)
9.60E-07
(4.80E-07)
3.90E-06
(1.95E-06)
7.08E-06
(3.54E-06)
3.42E-05
(1.71E-05)
2.05E-05
(1.03E-05)
3.66E-06
(1.83E-06)
3.74E-05
(1.87E-05)
2.35E-05
(I.17E-05)
1.20E-04
(6.00E-05)
8.16E-05
(4.08E-05)
2.57E-05
(1.28E-05)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
t-
U)
SCC Number Emission Source Control Device Pollutant
3-03-003-02 Oven Charging Post-NESHAP Controls 1-Methylnaphthalene
(continued) (continued) (continued)
2-Methylnaphthalene
Benzo(e)pyrene
Biphenyl
Di- and
Trimethylnaphthalenes
Dibenzofuran
Methyl- and
Dimethyldibenzofurans
Methylacenaphthylenes
Methylbenzfluoranthenes/
Methylbenzpyrene
Methylbiphenyls
Methylfluorenes
Methylphenanthrenes/
Methylanthracenes
Emission Factor
in Ib/ton
(kg/Mg)a
1.86E-05
(9.30E 06)
4.06E-05
(2.03E-05)
7.80E-06
(3.90E-06)
9.06E-06
(4.53E-06)
3.96E-05
(1.98E-05)
3.18E-05
(1.59E-05)
1.22E-05
(6.12E-06)
7.08E-06
(3.54E-06)
1.37E-05
(6.84E-06)
7.32E-06
(3.66E-06)
1.69E-05
(8.43E-06)
1.37E-05
(6.84E-06)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
u>
Lft
Lft
SCC Number Emission Source Control Device Pollutant
3-03-003-08 Door Leaks Uncontrolled Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j+k)fluoranthene
Chrysene/
Triphenylene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Emission Factor
in Ib/ton
(kg/Mg)a
105E-02
(5.35E-03)
7.59E-03
(3.86E-03)
9.41E-03
(4.79E-03)
6.71E-03
(3.42E-03)
1.12E-02
(5.71E-03)
8.80E-04
(4.48E-04)
3.58E-03
(1.82E-03)
6.49E-03
(3.30E-03)
3.14E-02
(1.60E-02)
1.88E-02
(9.58E-03)
3.36E-03
(1.71E-03)
3.43E-02
H.74E-02)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
Os
SCC Number Emission Source Control Device Pollutant
3-03-003-08 Door Leaks Uncontrolled Fluorene
(continued) (continued) (continued)
Naphthalene
Phenanthrene
Pyrene
1 -Methylnaphthalene
2-Methylnaphthalene
Benzo(e)pyrene
Biphenyl
Di- and
Trimethylnaphthalenes
Dibenzofuran
Methyl- and
Dimethyldibenzofurans
Methylacenaphthylenes
Emission Factor
in Ib/ton
(kg/Mgy
2.15E-02
(1.09E-02)
1.10E-01
(5.60E-02)
7.48E-02
(3.81E-02)
2.35E-02
(1.20E-02)
1.71E-02
(8.68E-03)
3.72E-02
(1.89E-02)
7.15E-03
(3.64E-03)
8.31E-03
(4.23E-03)
3.63E-02
(1.85E-02)
2.92E-02
(1.48E-02)
1.12E-02
(5.71E-03)
6.49E-03
(3.30E-03)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
UJ
SCC Number Emission Source Control Device Pollutant
3-03-003-08 Door Leaks Uncontrolled Methylbenzfluoranthenes/
(continued) (continued) (continued) Methylbenzpyrenes
Methylbiphenyls
Methylfluorenes
Methylphenanthrenes/
Methylanthracenes
3-03-003-08 Door Leaks Pre-NESHAP Controls Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j+k)fluoranthene
Chrysene/
Triphenylene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Emission Factor
in Ib/ton
(kg/Mgy
1.25E-02
(6.38E-03)
6.71E-03
(3.42E-03)
1.55E-02
(7.87E-03)
1.25E-02
(6.38E-03)
4.20E-04
(2.10E-04)
3.04E-04
(1.52E-04)
3.76E-04
(1.88E-04)
2.68E-04
(1.34E-04)
4.49E-04
(2.24E-04)
3.52E-05
(1.76E-05)
1.43E-04
(7.15E-05)
2.60E-04
(1.30E-04)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
-p-
u>
oo
SCC Number Emission Source Control Device Pollutant
3-03-003-08 Door Leaks Pre-NESHAP Controls Acenaphthylene
(continued) (continued) (continued)
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
1 -Methy Inaphthalene
2-Methylnaphthalene
Benzo(e)pyrene
Biphenyl
Emission Factor
in Ib/ton
(kg/Mg)a
1.25E-03
(6.27E-04)
7.52E-04
(3.76E-04)
1.34E-04
(6.71E-05)
1.37E-03
(6.85E-04)
8.60E-04
(4.30E-04)
4.40E-03
(2.20E-03)
2.99E-03
(1.50E-03)
9.42E-04
(4.71E-04)
6.82E-04
(3.41E-04)
1.49E-03
(7.44E-04)
2.86E-04
(1.43E-04)
3.32E-04
(1.66E-04)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
f-
u>
SCC Number Emission Source Control Device Pollutant
3-03-003-08 Door Leaks Pre-NESHAP Controls Di- and
(continued) (continued) (continued) Trimethylnaphthalenes
Dibenzofuran
Methyl- and
Dimethyldibenzofurans
Methylacenaphthylenes
Methylbenzfluoranthenes/
Methylbenzpyrene
Methylbiphenyls
Methylfluorenes
Methylphenanthrenes/
Methylanthracenes
3-03-003-08 Door Leaks Post-NESHAP Controls Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j+k)fluoranthene
Emission Factor
in Ib/ton
(kg/Mg)a
1 .45E-03
(7.26E-04)
1.17E-03
(5.83E-04)
4.49E-04
(2.24E-04)
2.60E-04
(1.30E-04)
5.02E-04
(2.51E-04)
2.68E-04
(1.34E-04)
6.18E-04
(3.09E-04)
5.02E-04
(2.51E-04)
1.68E-04
(8.40E-05)
1.21E-04
(6.07E-05)
1.50E-04
(7.52E-05)
1.07E-04
(5.37E-05)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
SCC Number Emission Source Control Device Pollutant
3-03-003-08 Door Leaks Post-NESHAP Controls Chrysene/
(continued) (continued) (continued) Triphenylene
Dibenz(a,h)anthracene
Indeno(l,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
Emission Factor
in Ib/ton
(kg/Mg)a
1.80E-04
(8.98E-05)
1.41E-05
(7.04E-06)
5.72E-05
(2.86E-05)
1.04E-04
(5.19E-05)
5.02E-04
(2.51E-04)
3.01E-04
(1.50E-04)
5.37E-05
(2.68E-05)
5.48E-04
(2.74E-04)
3.44E-04
(1.72E-04)
1.76E-03
(8.80E-04)
1.20E-03
(5.98E-04)
3.77E-04
(1.88E-04)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
CO
Os
SCC Number Emission Source Control Device Pollutant
3-03-003-08 Door Leaks Post-NESHAP Controls 1 -Methylnaphthalene
(continued) (continued) (continued)
2-MethyInaphthalene
Benzo(e)pyrene
Biphenyl
Di- and
Trimethylnaphthalenes
Dibenzofuran
Methyl- and
Dimelhyldibenzofurans
Methylacenaphthylenes
Methylbenzfluoranthenes/
Methylbenzpyrenes
Methylbiphenyls
Methylfluorenes
Methylphenanthrenes/
Methylanthracenes
Emission Factor
in Ib/ton
-------
TABLE 4.7-5. (Continued)
o\
N>
SCC Number Emission Source Control Device Pollutant
3-03-003-14 Lid Leaks Uncontrolled Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j+k)fluoranthene
Chrysene/
Triphenylene
Dibenz(a,h)anthracene
Indeno(l ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Emission Factor
in Ib/ton
(kg/Mgy
9.55E-04
(4.78E-04)
6.90E-04
(3.45E-04)
8.55E-04
(4.28E-04)
6.10E-04
(3.05E-04)
1.02E-03
(5.10E-04)
8.00E-05
(4.00E-05)
3.25E-04
(1.63E-04)
5.90E-04
(2.95E-04)
2.85E-03
(1.43E-03)
1.71E-03
(8.55E-04)
3.05E-04
(1.53E-04)
3.12E-03
(1.56E-03)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
o\
U)
SCC Number Emission Source Control Device Pollutant
3-03-003-14 Lid Leaks Uncontrolled Fluorene
(continued) (continued) (continued)
Naphthalene
Phenanthrene
Pyrene
1 -Methylnaphthalene
2-Methylnaphthalene
Benzo(e)pyrene
Biphenyl
Di- and
Trimethylnaphthalenes
Dibenzofuran
Methyl- and
Dimethyldibenzofurans
Methylacenaphthylenes
Emission Factor
in Ib/ton
(kg/Mg)a
1.96E-03
(9.78E-04)
l.OOE-02
(5.00E-03)
6.80E-03
(3.40E-03)
2.14E-03
(1.07E-03)
1.55E-03
(7.75E-04)
3.38E-03
(1.69E-03)
6.50E-04
(3.25E-04)
7.55E-04
(3.78E-04)
3.30E-03
(1.65E-03)
2.65E-03
(1.33E-03)
1.02E-03
(5.10E-04)
5.90E-04
(2.95E-04)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
SCC Number Emission Source Control Device Pollutant
3-03-003-14 Lid Leaks Uncontrolled Methylbenzfluoranthenes/
(continued) (continued) (continued) Methylbenzpyrenes
Methylbiphenyls
Methylfluorenes
Methylphenanlhrenes/
Methylanthracenes
3-03-003-14 Lid Leaks Pre-NESHAP Controls Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j +k)fluoranthene
Chrysene/
Triphenylene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Emission Factor
in Ib/ton
(kg/Mg)a
1.14E-03
(5.70E-04)
6.10E-04
(3.05E-04)
1.41E-03
(7.03E-04)
1.14E-03
(5.70E-04)
1.36E-04
(6.88E-05)
9.80E-05
(4.97E-05)
1.21E-04
(6.I6E-05)
8.66E-05
(4.39E-05)
1.45E-04
(7.34E-05)
1.14E-05
(5.76E-06)
4.62E-05
(2.34E-05)
8.38E-05
(4.25E-05)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
SCC Number Emission Source Control Device Pollutant
3-03-003-14 Lid Leaks Pre-NESHAP Controls Acenaphthylene
(continued) (continued) (continued)
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
1 -Methy Inaphthalene
2-Methylnaphthalene
Benzo(e)pyrene
Biphenyl
Emission Factor
in Ib/ton
(kg/Mg)a
4.05E-04
(2.05 E-04)
2.43E-04
(1.23E-04)
4.33E-05
(2.20E-05)
4.42E-04
(2.24E-04)
2.78E-04
(1.41 E-04)
1.42E-03
(7.20E-04)
9.66E-04
(4.90E-04)
3.04E-04
(1.54E-04)
2.20E-04
(1.12E-04)
4.80E-04
(2.43E-04)
9.23E-05
(4.68E-05)
1.07E-04
(5.44E-05)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
o\
ON
SCC Number Emission Source Control Device Pollutant
3-03-003-14 Lid Leaks Pre-NESHAP Controls Di- and
(continued) (continued) (continued) Trimethylnaphthalenes
Dibenzofuran
Methyl- and
Dimethyldibenzofurans
Methylacenaphthylenes
Methylbenzfluoranthenes/
Methylbenzpyrenes
Methylbiphenyls
Methylfluorenes
Methylphenanthrenes/
Methylanthracenes
3-03-003-14 Lid Leaks Post-NESHAP Controls Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j+k)fluoranthene
Emission Factor
in Ib/ton
(kg/Mg)a
4.69E-04
(2.38E-04)
3.76E-04
(1.91E-04)
1.45E-04
(7.34E-05)
8.38E-05
(4.25E-05)
1.62E-04
(8.21E-05)
8.66E-05
(4.39E-05)
2.00E-04
(1.01E-04)
1.62E-04
(8.21E-05)
1.15E-05
(5.73E-06)
8.28E-06
(4.14E-06)
1.03E-05
(5.13E-06)
7.32E-06
(3.66E-06)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
SCC Number Emission Source Control Device Pollutant
3-03-003-14 Lid Leaks Post-NESHAP Controls Chrysene/
(continued) (continued) (continued) Triphenylene
Dibenz(a, h)an thracene
Indeno(l ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
Emission Factor
in Ih/lon
(kg/Mg)a
1.22E-05
(6.12E-06)
9.60E-07
(4.80E-07)
3.90E-06
(1.95E-06)
7.08E-06
(3.54E-06)
3.42E-05
(1.71E-05)
2.05E-05
(1.03E-05)
3.66E-06
(1.83E-06)
3.74E-05
(1.87E-05)
2.35E-05
(1.17E-05)
1.20E-04
(6.00E-05)
8.16E-05
(4.08E-05)
2.57E-05
(1.28E-05)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
ON
OO
SCC Number Emission Source Control Device Pollutant
3-03-003-14 Lid Leaks Post-NESHAP Controls 1-Methy (naphthalene
(continued) (continued) (continued)
2-Methylnaphthalene
Benzo(e)pyrene
Biphenyl
Di- and
Trimethylnaphthalenes
Dibenzofuran
Methyl- and
Dimethyldibenzofurans
Methylacenaphthylenes
Methylbenzfluoranthenes/
Methylbenzpyrenes
Methylbiphenyls
Methylfluorenes
Methylphenanthrenes/
Methylanthracenes
Emission Factor
in Ib/ton
(kg/Mg)a
1.86E-05
(9.30E-06)
4.06E-05
(2.03E-05)
7.80E-06
(3.90E-06)
9.06E-06
(4.53E-06)
3.96E-05
(1.98E-05)
3.18E-05
(1.59E-05)
1.22E-05
(6.12E-06)
7.08E-06
(3.54E-06)
1.37E-05
(6.84E-06)
7.32E-06
(3.66E-06)
1.69E-05
(8.43E-06)
1.37E-05
(6.84E-06)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
Ox
SCC Number Emission Source Control Device Pollutant
3-03-003-14 Offtake Leaks Uncontrolled Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j+k)fluoranthene
Chrysene/
Triphenylene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Emission Factor
in Ib/ton
(kg/Mg)a
9.55E-04
(4.78E-04)
6.90E-04
(3.45E-04)
8.55E-04
(4.28E-04)
6.10E-04
(3.05E-04)
1.02E-03
(5.10E-04)
8.00E-05
(4.00E-05)
3.25E-04
(1.63E-04)
5.90E-04
(2.95E-04)
2.85E-03
(1.43E-03)
1.71E-03
(8.55E-04)
3.05E-04
(1.53E-04)
3.12E-03
O.56E-03)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
f-
U)
SCC Number Emission Source Control Device Pollutant
3-03-003-14 Offtake Leaks Uncontrolled Fluorene
(continued) (continued) (continued)
Naphthalene
Phenanthrene
Pyrene
1 -Methylnaphthalene
2-Methylnaphthalene
Benzo(e)pyrene
Biphenyl
Di- and
Trimethylnaphthalenes
Dibenzofuran
Methyl- and
Dimethyldibenzofurans
Methylacenaphthylenes
Emission Factor
in Ib/ton
(kg/Mg)a
1.96E-03
(9.78E-04)
l.OOE-02
(5.00E-03)
6.80E-03
(3.40E-03)
2.14E-03
(1.07E-03)
1.55E-03
(7.75E-04)
3.38E-03
(1.69E-03)
6.50E-04
(3.25E-04)
7.55E-04
(3.78E-04)
3.30E-03
(1.65E-03)
2.65E-03
(1.33E-03)
1.02E-03
(5.10E-04)
5.90E-04
(2.95E-04)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
OJ
-4
SCC Number Emission Source Control Device Pollutant
3-03-003-14 Offtake Leaks Uncontrolled Methylbenzfluoranthenes/
(continued) (continued) (continued) Methylbenzpyrenes
Methylbiphenyls
Methylfluorenes
Methylphenanthrenes/
Methylanthracenes
3-03-003-14 Offtake Leaks Pre-NESHAP Controls Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j+k)fluoranthene
Chrysene/
Triphenylene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Emission Factor
in Ib/ton
(kg/Mg)a
1.14E-03
(5.70E-04)
6.10E-04
(3.05E-04)
1.41E-03
(7.03E-04)
1.14E-03
(5.70E-04)
1.26E-04
(6.30E-05)
9.11E-05
(4.55E-05)
1.13E-04
(5.64E-05)
8.05E-05
(4.03E-05)
1.35E-04
(6.73E-05)
1.06E-05
(5.28E-06)
4.29E-05
(2.15E-05)
7.79E-05
(3.89E-05)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
SCC Number Emission Source Control Device Pollutant
3-03-003-14 Offtake Leaks Pre-NESHAP Controls Acenaphthylene
(continued) (continued) (continued)
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
1 -Methylnaphthalene
2-Methylnaphthalene
Benzo(e)pyrene
Biphenyl
Emission Factor
in Ib/ton
(kg/Mg)a
3.76E-04
(1.88E-04)
2.26E-04
(1.13E-04)
4.03E-05
(2.01E-05)
4.11E-04
(2.06E-04)
2.58E-04
(1.29E-04)
1.32E-03
(6.60E-04)
8.98E-04
(4.49E-04)
2.82E-04
(1.41E-04)
2.05E-04
(1.02E-04)
4.46E-04
(2.23E-04)
8.58E-05
(4.29E-05)
9.97E-05
(4.98E-05)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
-J
UJ
SCC Number Emission Source Control Device Pollutant
3-03-003-14 Offtake Leaks Pre-NESHAP Controls Di- and
(continued) (continued) (continued) Trimethy (naphthalenes
Dibenzofuran
Methyl- and
Dimethyldibenzofurans
Methylacenaphthylenes
Methy Ibenzfl uoranthenes/
Methylbenzpyrenes
Methylbiphenyls
Methylfluorenes
Methylphenanthrenes/
Methylanthracenes
3-03-003-14 Offtake Leaks Post-NESHAP Controls Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j+k)fluoranthene
Emission Factor
in Ib/ton
(kg/Mg)a
4.36E-04
(2.18E-04)
3.50E-04
(1.75E-04)
1.35E-04
(6.73E-05)
7.79E-05
(3.89E-05)
1.50E-04
(7.52E-05)
8.05E-05
(4.03E-05)
1.85E-04
(9.27E-05)
1.50E-04
(7.52E-05)
3.82E-05
(1.91E-05)
2.76E-05
(1.38E-05)
3.42E-05
(1.71E-05)
2.44E-05
(1.22E-05)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
SCC Number Emission Source Control Device Pollutant
3-03-003-14 Offtake Leaks Post-NESHAP Controls Chrysene/
(continued) (continued) (continued) Triphenylene
Dibenz(a,h)anthracene
Indeno(l,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
Emission Factor
in Ib/ton
(kg/Mg)a
4.08E-05
(2.04E-05)
3.20E-06
(1.60E-06)
1.30E-05
(6.50E-06)
2.36E-05
(1.18E-05)
1.14E-04
(5.70E-05)
6.84E-05
(3.42E-05)
1.22E-05
(6.10E-06)
1.25E-04
(6.23E-05)
7.82E-05
(3.91E-05)
4.00E-04
(2.00E-04)
2.72E-04
(1.36E-04)
8.56E-05
(4.28E-05)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-5. (Continued)
u>
-j
SCC Number Emission Source Control Device Pollutant
3-03-003-14 Offtake Leaks Post-NESHAP Controls 1-Methylnaphthalene
(continued) (continued) (continued)
2-Methylnaphthalene
Benzo(e)pyrene
Biphenyl
Di- and
Trimethylnaphthalenes
Dibenzofuran
Methyl- and
Dimethyldibenzofurans
Methylacenaphthylenes
Methylbenzfluoranthenes/
Methylbenzpyrenes
Methylbiphenyls
Methylfluorenes
Methylphenanthrenes/
Methylanthracenes
Emission Factor
in Ib/ton
(kg/Mg)a
6.20E-05
(3.10E-05)
1.35E-04
(6.76E-05)
2.60E-05
(1.30E-05)
3.02E-05
(1.51E-05)
1.32E-04
(6.60E-05)
1.06E-04
(5.30E-05)
4.08E-05
(2.04E-05)
2.36E-05
(1.18E-05)
4.56E-05
(2.28E-05)
2.44E-05
(1.22E-05)
5.62E-05
(2.81E-05)
4.56E-05
(2.28E-05)
Emission Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
"Emission factors in Ib/ton (kg/Mg) of coal charged.
(continued)
-------
listed in Table 4.7-4 by the percentage of a particular PAH or POM found in BSO listed in Table 4.7-1.
Emission factors were calculated for all the 16 priority PAH and for those POM compounds that
individually constitute greater than 1 percent of BSO. The 1 percent cut-off was used in order to allow
for a more manageable presentation of the factors in Table 4.7-5; factors developed for POM compounds
below the 1 percent cut-off result in a very small quantity of emissions relative to the overall source
categories. It must be reemphasized that these are order-of-magnitude estimates mainly due to the
variability in the composition of coke oven gas.
The uncontrolled emission factors reported are for poorly controlled batteries. With the
exception of charging, an uncontrolled condition is difficult to define for the various coke oven emission
points because routine operations involve some degree of control. Any emission estimate for a specific
battery should consider the number of leaking doors, lids, or offtakes and the range of emission rates
from these points (U.S. EPA, 1987).
Hence, the 1993 MACT standard governing emissions during charging and from door and
topside leaks does not specify the control techniques to be used. Instead, the standard limits visible
emissions, which has been the typical regulatory approach used by States and internationally. Coke plant
owners and operators can choose from the known control techniques listed in Table 4.7-2 to comply with
the visible emissions limitations. It is estimated that when the 1993 MACT standard is fully
implemented, nationwide coke oven emissions from charging and leaks will be reduced to 300 tpy
(270 Mg/yr) or by about 66 percent by the end of 1995 (57 FR 57534).
Source Locations
In 1983,25.8 million tons (23.5 million Mg) of coke were produced in U.S. byproduct
coke ovens (U.S. EPA, 1987). At the end of 1990, the industry's total production capacity was estimated
to be 30 million tpy (27 million Mg/yr) coke (actual 1990 production being somewhat lower).
Table 4.7-6 lists the operating U.S. byproduct coke plants and the identification number of the batteries
located at the plant (57 FR 57534).
4-376
-------
TABLE 4.7-6. COKE OVEN BATTERIES CURRENTLY OPERATING
IN THE UNITED STATES
Plant (Location)
Battery Identification Number
ABC Coke (Tarrant, AL)
Acme Steel (Chicago, IL)
Armco, Inc. (Middletown, OH)
Armco, Inc. (Ashland, KY)
Bethlehem Steel (Bethlehem, PA)
Bethlehem Steel (Burns Harbor, IN)
Bethlehem Steel (Lackawanna, NY)
Citizens Gas (Indianapolis, IN)
Empire Coke (Holt, AL)
Erie Coke (Erie, PA)
A
5
6
1
2
1
2
3
3
4
A
2
3
1
2
7
8
E
H
1
1
2
A
B
(continued)
4-377
-------
TABLE 4.7-6. (Continued)
Plant (Location)
Battery Identification Number
Geneva Steel (Provo, UT)
Gulf States Steel (Gadsden, AL)
Inland Steel (East Chicago, IN)
Koppers (Woodward, AL)
LTV Steel (Cleveland, OH)
LTV Steel (Pittsburgh, PA)
LTV Steel (Chicago, IL)
LTV Steel (Warren, OH)
1
2
3
4
2
3
6
7
9
10
11
1
2A
2B
4A
4B
5
6
7
PI
P2
P3N
P3S
P4
(continued)
4-378
-------
TABLE 4.7-6. (Continued)
Plant (Location)
Battery Identification Number
National Steel (Ecorse, MI)
National Steel (Granite City, IL)
New Boston Coke (Portsmouth, OH)
Sharon Steel (Monessen, PA)
Shenango (Pittsburgh, PA)
Sloss Industries (Birmingham, AL)
Toledo Coke (Toledo, OH)
Tonawanda Coke (Buffalo, NY)
USX (Clairton, PA)
A
B
1
IB
2
1
4
3
4
5
C
1
1
2
3
7
8
9
13
14
15
19
20
B
(continued)
4-379
-------
TABLE 4.7-6. (Continued)
Plant (Location) Battery Identification Number
USX (Gary, IN) 23
5
7
Wheeling-Pittsburgh (East Steubenville, WV) 1
2
3
8
NOTE: This list is subject to change as market conditions change, facility ownership changes, plants are
closed, etc. The reader should verify the existence of particular facilities by consulting current lists
and/or the plants themselves. The level of POM emissions from any given facility is a function of
variables such as capacity, throughput and control measures, and should be determined through
direct contacts with plant personnel. These operating plants and locations were current as of
April 1, 1992.
Source: 57 FR 57534.
4-380
-------
4.7.2 Coke Ovens: Pushing. Quenching, and Battery Stacks
Process Description
Although the large majority of coke oven emissions occur during charging and from door
and topside leaks during coking, some POM may be emitted from battery exhaust stacks during coking
and afterwards during product handling. Because the emissions from battery stacks and product handling
are small compared to those from charging, door, and topside leaks, these emissions were not addressed
in the 1993 MACT standard. Instead, they will be the focus of an upcoming rulemaking (57 FR 57534).
As mentioned previously, cracks can develop in the oven wall during coking due to coke
expansion. If cracks occur, some raw coke oven gas and the POM it contains can escape to the flue
system and be exhausted to the atmosphere via the oven battery combustion exhaust stacks. These stacks
are intended only for the exhaust from the fuel burned to provide the heat for coking and not for coke
oven gas, which is supposed to be transported to the byproduct recovery portion of the coke plant
(57 FR 57534).
At the end of the coking cycle, the product is handled in steps called "pushing" and
"quenching." As depicted in Figure 4.7-1, there are doors at both ends of a coke oven that are removed
when coking is finished, and the incandescent coke is pushed out the coke side of the oven by a ram,
which is extended from the pusher machine. The coke is pushed through a coke guide into a special
railroad car, called a quench car, which traverses the coke side of the battery. The quench car carries the
coke to the end of the battery to a quench tower where it is deluged with several thousand gallons of
water so that it will not continue to burn after being exposed to air. The quenched coke is discharged
onto an inclined coke wharf to allow excess water to drain and the coke to cool to a reasonable handling
temperature (U.S. EPA, 1987).
Gates along the lower edge of the wharf control the rate of coke falling on a conveyor belt,
which carries the coke to the crushing and screening system. The coke is then crushed and screened to
obtain the optimum size for the particular blast furnace operation in which it is to be used. The undersize
4-381
-------
coke generated by the crushing and screening operations is used in other steel plant processes, stockpiled,
or sold (U.S. EPA, 1987).
Coke oven gas and the POM they contain can be released during pushing and quenching
due to equipment failure or poor operation. If problems occur in the underfiring system of an oven, or if
the oven is pushed out of sequence, or is on an accelerated schedule, the coal may not be completely
converted to coke. When this happens, inadequately coked coal (called "green coke") may be pushed
from the oven. Pushing emissions from inadequate coking or green coke are likely to contain POM.
These compounds may continue to be emitted when the green coke is quenched with water
(57 FR 57534).
Control techniques that have been devised for these operations are listed in Table 4.7-2.
These techniques have been implemented to various degrees. Emissions from coke pushing can be
controlled by the use of containment/capture and control devices such as hooded, mobile scrubber cars;
shed enclosures over the coke side of the battery, evacuated to wet scrubbers or wet ESPs; or traveling
hoods with a fixed duct to a stationary gas cleaner. Coke quenching emissions can be controlled mainly
through process changes such as the use of single or multiple baffles in the quench tower and the use of
only clean water for quenching. Dry quenching may be another option, but this would require additional
capture and control devices. Leaks into battery stacks may be controlled through the use of maintenance
procedures such as patching cracks in oven walls as needed and containment/capture and control devices
such as wet scrubbers, ESPs, or baghouses by which exhaust gases are treated to remove coke oven
emissions (Kelly, 1983). The new rule due in 2000 may standardize the use of many of these control
techniques and/or mandate the use of others.
Emission Factors
Emission factors for POM from pushing, quenching, and battery stacks developed from
available data are given in Tables 4.7-7 and 4.7-8. The quantity and composition of pushing emissions
are variable because they depend on the degree of upset to the system. If an oven is pushed out of
sequence or before the end of the coking cycle, the green coke will emit more gas and POM than
normally expected. The same is true for quenching emissions. The more green coke that is contained in
4-382
-------
TABLE 4.7-7. POM EMISSION FACTORS FOR COKE OVENS: PUSHING AND BATTERY STACKS
f-
U)
00
SCC Number Emission Source Control Device Pollutant
3-03-003-03 Oven Pushing Uncontrolled Benz(a)anlhracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j+k)fluoranthene
Chrysene/Triphenylene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Average Emission
Factor in Ib/ton
(kg/Mg)a
4.8E-04
(2.4E-04)
3.5E-04
(1.7E-04)
4.3E-04
(2.1E-04)
3.1E-04
(1.5E-04)
5.1E-04
(2.5E-04)
4.1E-05
(2.0E-05)
1.6E-04
(8.1E-05)
3.0E-04
(1.5E-04)
1.4E-03
(7.1E-04)
8.6E-04
(4.3E-04)
1.5E-04
(7.6E-05)
1.6E-03
(7.8E-04)
Emission Factor Range
in Ib/ton
(kg/Mg)a
3.1E-04-6.5E-04
(1.5E-04-3.3E-04)
2.2E-04 - 4.7E-04
(1.1E-04-2.4E-04)
2.7E-04 - 6.8E-04
(1.4E-04-2.9E-04)
2.0E-04 - 4.2E-04
(9.8E-05-2.1E-04)
3.3E-04 - 6.9E-04
(1.6E-04-3.4E-04)
2.6E-05 - 5.5E-05
(1.3E-05-2.8E-05)
1.0E-04-2.2E-04
(5.2E-05- 1.1E-04)
1.9E-04-4.0E-04
(9.4E-05 - 2.0E-04)
9.1E-04-1.9E-03
(4.6E-04 - 9.7E-04)
5.5E-04- 1.2E-03
(2.7E-04 - 5.8E-04)
9.8E-05 -2.1E-04
(4.9E-05-1.0E-04)
1.0E-03-2.1E-03
(5.0E-04-1.1E-03)
Emission
Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-7. (Continued)
4*.
oo
SCC Number Emission Source Control Device Pollutant
3-03-003-03 Oven Pushing Uncontrolled Fluorene
(continued) (continued) (continued)
Naphthalene
Phenanthrene
Pyrene
1 -Methy Inaphthalene
2-Methylnaphthalene
Benzo(a)fluoranthene
Benzo(a)fluorene
Benzo(e)pyrene
Biphenyl
Carbazole
Coronene
Average Emission
Factor in Ib/ton
(kg/Mg)a
9.8E-04
(4.9E-04)
0.017
(8.7E-03)
3.4E-03
(1.7E-03)
1.1E-03
(5.3E-04)
7.5E-04
(3.8E-04)
1.7E-03
(8.5E-04)
8.1E-04
(4.1E-05)
9.2E-05
(4.6E-05)
3.3E-04
(1.6E-04)
3.8E-04
(1.9E-04)
1.4E-04
(7.1E-05)
2.0E-05
(l.OE-05)
Emission Factor Range
in Ib/ton
(kg/Nig)'
6.3E-04-1.3E-03
(3.1E-04-6.6E-04)
0.011-0.024
(5.6E-03- 0.012)
2.2E-03 - 4.6E-03
(1.1E-03-2.3E-03)
6.8E-04-1.5E-03
(3.4E-04 - 7.3E-04)
4.8E-04-1.0E-03
(2.4E-04-5.1E-04)
1.1E-03-2.3E-03
(5.4E-04-1.1E-03)
5.2E-05-1.1E-04
(2.6E-05 - 5.5E-05)
5.9E-05 - 1.2E-04
(2.9E-05 - 6.2E-05)
2.1E-04-4.4E-04
(1.0E-04-2.2E-04)
2.4E-04-5.1E-04
(1.2E-04-2.6E-04)
9.1E-05-1.9E-04
(4.6E-05 - 9.7E-05)
1.3E-05-2.8E-05
(6.5E-06-1.4E-05)
Emission
Factor,
Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-7. (Continued)
U)
oo
SCC Number Emission Source Control Device Pollutant
3-03-003-03 Oven Pushing Uncontrolled Cyclopenta(cd)pyrene
(continued) (continued) (continued)
Di- and Tri methyl naphthalenes
Dibenzofuran
Dibenzothiophene
Methyl- and
Dimethyldibenzofurans
Methylacenaphthylcnes
Methylbenzfluoranthenes/
Methylbenzpyrene
Methylbiphenyls
Methylfluorenes
Methylphenanthrcnes/
Methylanthracenes
Perylene
Average Emission
Factor in Ib/ton
(kg/Mg)a
3.1E-05
(1.5E-05)
1.7E-03
(8.3E-04)
1.3E-03
(6.6E-04)
2.0E-04
(l.OE-04)
5.1E-04
(2.6E-04)
3.0E-04
(1.5E-04)
5.4E-04
(2.7E-04)
3.1E-04
(1.5E-04)
7.0E-04
(3.5E-04)
5.7E-04
(2.9E-04)
9.2E-05
(4.6E-05)
Emission Factor Range
in Ib/ton
(kg/Mg)a
2.0E-05 - 4.2E-05
(9.8E-06-2.1E-05)
1.1E-03-2.2E-03
(5.3E-04- 1.1E-03)
8.5E-04 - 1.8E-03
(4.2E-04 - 9.0E-04)
1.3E-04-2.8E-04
(6.5E-05-1.4E-04)
3.3E-04 - 6.9E-04
(1.6E-04-3.5E-04)
1.9E-04-4.0E-04
(9.4E-05 - 2.0E-04)
3.5E-04 - 7.3E-04
(1.7E-04-3.7E-04)
2.0E-04 - 4.2E-04
(9.8E-05-2.1E-04)
4.5E-04 - 9.6E-04
(2.2E-04 - 4.8E-04)
3.6E-04 - 7.8E-04
(1.8E-04 - 3.9E-04)
5.9E-05 - 1.2E-04
(2.9E-05 - 6.2E-05)
Emission
Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-7. (Continued)
to
oo
SCC Number Emission Source Control Device Pollutant
3-03-003-06 Oven Underfiring Uncontrolled Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(j+k)fluoranthene
Chrysene/Triphenylene
Dibenz(a,h)anthracene
Indeno(l ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Average Emission
Factor in Ib/ton
(kg/Mg)a
6.1E-05
(3.1E-05)b
4.4E-05
(2.2E-05)b
5.5E-05
(2.7E-05)b
3.9E-05
(2.0E-05)b
6.5E-05
(3.3E-05)b
5.2E-06
(2.6E-06)b
2.1E-05
(1.0E-05)b
3.8E-05
(1.9E-05)b
1.8E-04
(9.1E-05)b
1.1E-04
(5.5E-05)b
2.0E-05
(9.8E-06)b
2.0E-04
n.OE-04)b
Emission Factor Range Emission
in Ib/ton Factor
(kg/Mg)a Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-7. (Continued)
OJ
00
SCC Number Emission Source Control Device Pollutant
3-03-003-06 Oven Underfiring Uncontrolled Fluorene
(continued) (continued) (continued)
Naphthalene
Phenanthrene
Pyrene
1 -Methylnaphthalene
2-Methylnaphthalene
Benzo(a)fluoranthenc
Benzo(a)fluorene
Benzo(e)pyrene
Biphenyl
Carbazole
Coronene
Average Emission
Factor in Ib/ton
(kg/Mg)a
1.3E-04
(6.3E-05)b
2.2E-03
(1.1E-03)6
4.4E-04
(2.2E-04)b
1.4E-04
(6.8E-05)6
9.6E-05
(4.8E-05)6
2.2E-04
(l.lE-04)b
l.OE-05
(5.2E-06)b
1.2E-05
(5.9E-06)b
4.2E-05
(2.1E-05)b
4.8E-05
(2.4E-05)6
1.8E-05
(9.1E-06)b
2.6E-06
(1.3E-06)b
Emission Factor Range Emission
in Ib/ton Factor
(kg/Mg)a Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.7-7. (Continued)
U)
00
oo
SCC Number Emission Source Control Device Pollutant
3-03-003-06 Oven Underfiring Uncontrolled Cyclophenta(cd)pyrene
(continued) (continued) (continued)
Di- and Trimethyl naphthalenes
Dibenzofuran
Dibenzothiophene
Methyl- and
Dimethyldibenzofurans
Methylacenaphthylenes
Methylbenzfluoranthenes/
Methylbenzpyrene
Methylbiphenyls
Methylfluorenes
Methylphenanthrenes/
Methylanthracenes
Perylene
Average Emission
Factor in Ib/ton
(kg/Mg)a
3.9E-06
(2.0E-06)b
2.1E-04
(l.lE-04)b
1.7E-04
(8.5E-05)b
2.6E-05
(1.3E-05)b
6.5E-05
(3.3E-05)b
3.8E-05
(1.9E-05)b
6.9E-05
(3.5E-05)b
3.9E-05
(2.0E-05)b
9.0E-05
(4.5E-05)b
7.3E-05
(3.6E-05)b
1.2E-05
(5.9E-06)b
Emission Factor Range Emission
in Ib/ton Factor
(kg/Mg)a Rating
E
E
E
E
E
E
E
E
E
E
E
"Emission factors in Ib/ton (kg/Mg) of coal charged.
bPOM leaks are transported to the battery stacks through the oven underfiring system.
Source: Trenholm and Beck, 1978; Kirton and Crisp, 1991.
-------
TABLE 4.7-8. POM EMISSION FACTORS FOR COKE OVENS: QUENCHING
CO
00
Average Emission Factor
in lb/tona
SCC Number Emission Source Control Device Pollutant (kg/Mg)
3-03-003-04 Quenching - Nongreen Uncontrolled Benz(a)anthracenes/Chrysene
Coke
Benzo(a)pyrene
Benzofluoranthene/Benzo(e)pyrene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene/Biphenyl
Acenaphthylene/Biphenylene
Anthracene/Phenanthrene
Fluoranthene
Fluorene
Naphthalene
Pyrene
3-Methylcholanthrene
1.3E-04
(6.5E-05)b
6.5E-04
(3.2E-04)b
1.6E-04
(7.8E-05)6
6.6E-06
(3.3E-06)b
5.5E-04
(2.8E-04)b
5.5E-03
(2.7E-03)b
6.9E-03
(3.5E-03)b
1.5E-03
(7.6E-04)b
4.8E-03
(2.4E-03)b
0.033
(0.017)b
1.4E-03
(7.1E-04)b
1.2E-05
(5.9E-06)b
Emission Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.7-8. (Continued)
u>
SCC Number Emission Source Control Device Pollutant
3-03-003-04 Quenching - Nongreen Uncontrolled Benzothiophene
(continued) Coke (continued)
(continued)
C16H12PAH
C16H16PAH
Carbazole
Dibcnzofuran/Methylbiphenyl
Dibenzothiophene
Dihydrobenzofluorene
Dimethylnaphthalenes
Indene
Methylanthracenes
Methylchrysenes
Methylfluoranthenes/Methylpyrenes
Average Emission Factor
in lb/tona
(kg/Mg)
1.7E-03
(8.6E-04)b
9.3E-05
(4.7E-05)b
2.4E-05
(1.2E-05)b
8.1E-04
(4.1E-04)b
2.1E-03
(1.0E-03)b
3.5E-04
(1.7E-04)b
8.8E-05
(4.4E-05)b
5.3E-04
(2.7E-04)b
2.8E-04
(1.4E-04)6
6.1E-04
(3.0E-04)b
2.2E-05
(l.lE-05)b
1.9E-04
(9.5E-05)b
Emission Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.7-8. (Continued)
vo
Average Emission Factor
SCC Number Emission Source Control Device Pollutant
3-03-003-04 Quenching - Nongreen Uncontrolled Methylnaphthalenes
(continued) Coke (continued)
(continued)
Naphthobenzothiophene
Perylene
3-03-003-04 Quenching - Nongreen Clean Water Benz(a)anthracenes/Chrysene
Coke
Benzo(a)pyrene
Indeno (l,2,3-cd)pyrene
Acenaphthene/Biphenyl
Acenaphthylene/B ipheny lene
Anthracene/Phenanthrene
Benzo(ghi)perylene
Fluoranthene
Fluorene
in lb/tona
(kg/Mg)
2.9E-03
(1.4E-03)b
5.3E-06
(2.6E-06)b
4.6E-05
(2.3E-05)b
2.8E-05
(1.4E-05)
2.0E-04
(9.8E-05)
3.6E-06
(1.8E-06)
4.7E-06
(2.3E-06)
1.4E-05
(6.8E-06)
1.9E-04
(9.7E-05)
2.4E-05
(1.2E-05)
6.2E-05
(3.1E-05)
3.2E-05
(1.6E-05)
Emission Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.7-8. (Continued)
VO
N>
Average Emission Factor
in lb/tona
SCC Number Emission Source Control Device Pollutant (kg/Mg)
3-03-003-04 Quenching - Nongreen Clean Water Naphthalene
(continued) Coke (continued)
(continued)
Pyrene
3-Methylcholanthrene
Benzothiophene
C16H12PAH
Dibenzofuran/Methylbiphenyl
Dibenzothiophene
Dihydrobenzofluorene
Dimethylnaphthalenes
Mcthylanthracenes
Methylfluoranthenes/Methylpyrenes
Methylnaphthalencs
2.0E-04
(l.OE-04)
2.6E-05
(1.3E-05)
2.1E-05
(I.1E-05)
1.1E-06
(5.3E-07)
2.6E-06
(1.3E-06)
1.6E-05
(7.9E-06)
8.2E-06
(4.1E-06)
2.3E-05
(1.1E-05)
3.3E-05
(1.6E-05)
9.0E-05
(4.5E-05)
7.3E-06
(3.7E-06)
4.7E-05
(2.3E-05)
Emission Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.7-8. (Continued)
SCC Number Emission Source Control Device Pollutant
3-03-003-04 Quenching - Green Clean Water Benz(a)anthracenes/Chrysene
Coke
Benzo(a)pyrene
Acenaphthene/B ipheny 1
Acenaphthylene/Biphenylene
Anthracene/Phenanthrene
Fluoranthene
Fluorene
Naphthalene
Pyrene
3-Methylcholanthrene
Benzothiophene
Dibenzofuran/Methylbiphenyl
Average Emission Factor
in lb/tona
(kg/Mg)
9.4E-06
(4.7E-06)
9.7E-05
(4.9E-05)
2.7E-05
(1.4E-05)
9.8E-05
(4.9E-05)
4.5E-04
(2.3E-04)
1.2E-04
(5.9E-05)
9.6E-05
(4.8E-05)
5.1E-04
(2.6E-04)
1.3E-04
(6.6E-05)
2.0E-05
(9.8E-06)
1.6E-06
(8.0E-07)
8.0E-05
(4.0E-05)
Emission Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.7-8. (Continued)
Average Emission Factor
in lb/tona
SCC Number Emission Source Control Device Pollutant (kg/Mg)
3-03-003-04 Quenching - Green Clean Water Dibenzothiophene
(continued) Coke (continued)
(continued)
Dihydrobenzofluorene
Dimethylnaphthalenes
Methylanthracenes
Methylfluoranthenes/Methylpyrenes
Methyl naphthalenes
Perylene
3.8E-06
(1.9E-06)
2.3E-05
(1.2E-05)
3.3E-04
(1.6E-04)
3.1E-04
(1.5E-04)
6.3E-05
(3.2E-05)
1.9E-04
(9.4E-05)
3.1E-05
(1.5E-05)
Emission Factor
Rating
D
D
D
D
D
D
D
'Emission factors in Ib/ton (kg/Mg) of coal charged.
bContaminated water used for quenching.
Source: Laube and Drummond, 1979.
-------
the product, the greater the quantity of emissions liberated during quenching. Finally, the
quantity of leaks into the combustion exhaust stacks at any given plant will vary; it is difficult to
establish an emission factor for battery stacks although the emissions are still considered
significant enough to warrant control.
Because the focus of regulatory efforts has been on the initial charging operation
and door and topside leaks, little new data has been developed regarding emissions from pushing,
quenching, and battery stacks. Only one report (Trenholm and Beck, 1978) documented BSO
emissions from pushing. Individual POM emission factors for pushing were derived from the
BSO emission factor shown in Table 4-7-4 using the speciation profile in Table 4.7-1. Likewise,
this report was the only one to report BSO emissions from battery stacks, and the individual PAH
emission factors were derived from this single piece of data. Therefore, caution is again
recommended in the use of these emission factors.
Of these three emission points, the most attention has been paid to the quenching
operation because at one time, it was suspected as being the most significant POM emission
source after door leaks. In one test program (Laube and Drummond, 1979), the effect of using
clean versus contaminated (reused) quench water as a control technique was evaluated. The tests
indicated that the use of clean quench water reduced total PAH emissions by about 95 percent.
This finding spurred further investigation of this particular control technique yielding somewhat
similar results (Johnson et al., 1990).
The first test program investigating quenching emissions was undertaken in
support of Federal rule development, and individual PAH were analyzed, the data from which
can be used to develop emission factors. The test program indicated that benzo(a)pyrene
emissions from quenching were much less than from the other coke oven points. This may be
due to the time in the coking cycle that quenching takes place, i.e., most volatiles have been
driven off the coal by the time it has been coked and is ready to be quenched. Thus, the average
BSO speciation profile used for the other coke oven points may not be the best indication of the
individual PAH composition of emissions from quenching. Hence, the PAH emission factors for
4-395
-------
quenching have been developed from this single test program (Laube and Drummond, 1979), not
from the BSO emission factor shown in Table 4.7-4.
The use of baffles as a control technique in the quenching operation targets
paniculate emissions, not POM per se, but because POM is often associated with particulate
matter, the use of baffles still qualifies as a POM control technique. Tests indicate that baffles
can reduce total particulate by 50 to 75 percent.
Even when a particular control technique is in place, the variability in the quantity
and composition of coke oven emissions from quenched coke makes it impossible to establish an
accurate overall emission factor. Hence, as with pushing and battery stack emissions, a range of
emission factors from quenching is provided, which is derived from BSO emission factors that
have been reported. Because this range encompasses the values for emission factors from other
reports of emissions of total PAH or benzo(a)pyrene, the other reports are not included
separately.
Source Locations
Pushing and quenching operations are carried out and battery stacks are located at
all of the coke oven plants listed in Table 4.7-5.
4.7.3 Coke Byproduct Recovery Plants
Process Description
Volatile components that are driven off the coal during coking are transported to
the byproduct recovery portion of coke plants fitted with such operations. Coke oven gas that
has not leaked out leaves the coke oven battery through standpipes, passes into goosenecks, and
travels through a damper valve to the gas collection main, which directs it to the byproduct
recovery plant. This gas accounts for 20 to 35 percent by weight of the initial coal charge and is
4-396
-------
composed of water vapor, tar, light oils, heavy hydrocarbons, and other chemical compounds,
including POM (U.S. EPA, 1987).
Following the process flow diagram in Figure 4.7-2, raw coke oven gas exits the
ovens at temperatures of 1,400 to 1,600°F (760 to 870°C) and is shock-cooled by spraying
recycled flushing liquor in the gooseneck. This spray cools the gas to 180 to 210°F (80 to
100°C), precipitates tar, condenses various vapors, and serves as the carrying medium for the
condensed compounds. These products are separated from the liquor in a decanter and are
subsequently processed to yield tar and tar derivatives. The gas is then passed either to a final tar
extractor or an electrostatic precipitator for additional tar removal. When the gas leaves the tar
extractor, it carries 75 percent of the ammonia and 95 percent of the light oil originally present
when leaving the oven (U.S. EPA, 1987).
The ammonia is recovered either as an aqueous solution by water absorption or as
ammonium sulfate salt. Ammonium sulfate is crystallized in a saturator, which contains a
solution of 5 to 10 percent sulfuric acid and is removed by an air injector or centrifugal pump.
The salt is dried in a centrifuge and packaged. The ammonia-stripped gas leaving the saturator at
about 140°F (60°C) is taken to final coolers or condensers, where it is typically cooled with
water to approximately 75 °F (24°C). During this cooling, much of the naphthalene separates
and is carried along with the wastewater and recovery (U.S. EPA, 1987).
After naphthalene is removed, the remaining gas is passed into a light oil or
benzol scrubber, over which is circulated a heavy petroleum fraction called wash oil or a coal-tar
oil that serves as the absorbent medium. The oil is sprayed in the top of the packed absorption
tower while the gas flows up through the tower. The wash oil absorbs about 2 to 3 percent of its
weight of light oil, with a removal efficiency of about 95 percent of the light oil vapor in the gas.
The rich wash oil is passed to a countercurrent steam stripping column. The steam and light oil
vapors pass upward from the still through a heat exchanger to a condenser and water separator.
The light oil may be sold as crude or processed to recover benzene, toluene, xylene, and solvent
naphtha (U.S. EPA, 1987).
4-397
-------
After tar, ammonia, and light oil removal, the gas undergoes a final
desulfurization process at some coke plants before being used as fuel. The "clean" coke oven gas
has a rather high heating value, on the order of 550 Btu/stdft3 (20 MJ/Nm3). Typically, 35 to
40 percent of the gas is returned to fuel the coke oven combustion system, and the remainder is
used for other plant heating needs (U.S. EPA, 1987).
The points emitting the highest POM concentrations in byproduct recovery plants
are the tar decanter, tar dewatering and storage, tar distillation products, naphthalene separator,
and final-cooler cooling tower. The data suggest that POM accumulates as a concentrate in
liquified streams (tars, flushing liquor, tar products, wash and wastewaters), and can be emitted
when the streams are processed or used, such as when recycled water from the final cooler passes
through the open cooling tower. Naphthalene was identified as being the POM emitted in the
greatest quantity (Van Osdell, 1979).
As mentioned previously, benzene emissions from the byproduct recovery portion
of coke plants are now regulated. The nature of the controls required by a benzene NESHAP
promulgated in 1989 have the effect of controlling much of the POM emissions from the plant as
well because POM and benzene are emitted from many of the same points. The benzene
emission control techniques that also control POM are described next.
Gas blanketing with clean coke oven gas from the gas holder (or battery underfire
system) is the control technology required by the 1989 benzene NESHAP for tar processing
(54 FR 38044). With this technology, the different tar processing points are enclosed and a
positive (or negative) pressure blanket of clean coke oven gas is piped in. Using a series of
piping connections and flow inducing devices (if necessary), vapor emissions from the enclosed
sources are transported back into the clean gas system (the coke-oven battery holder, the
collecting main, or another point in the byproduct recovery process). Ultimate control of the
vapors (benzene and all other emissions) is accomplished by the combustion of the coke oven gas
(U.S. EPA, 1984).
4-398
-------
Such systems are currently in use at some byproduct recovery plants and
reportedly have operated without difficulty. Examples of gases that may be used as the gas
blanket include dirty or clean coke gas, nitrogen, or natural gas (U.S. EPA, 1984). The control
efficiency for benzene is estimated to be 98 percent except for the tar decanter, where the
efficiency is estimated to be 95 percent. The control efficiency for POM can be assumed to be
the same or better because POM is less volatile than benzene; hence less of it should escape the
blanketing system.
The 1989 benzene NESHAP requires that all benzene emissions from naphthalene
processing, final coolers, and final-cooler cooling towers be eliminated (54 FR 38044). The
available controls, which reduce all emissions including POM to zero, are conversion to a
different type of cooling tower or elimination of the cooling tower. A facility with a direct-water
final cooler could insert a one-stage mixer-settler into the final cooling process and thus obtain
the benefits of a tar-bottom cooler. Although a tar-bottom cooler does not eliminate emissions
from the cooling tower, it does eliminate emissions associated with the physical separation of
naphthalene and water. Alternatively, the facility could convert to a wash oil final cooler, which
effectively eliminates the emissions associated with direct water or tar-bottom coolers because
the wash oil is cooled by an indirect heat exchanger, thereby eliminating the need for a cooling
tower. Wash oil is separated after it leaves the heat exchanger and recirculates back through the
circulation tank to the final cooler (U.S. EPA, 1984).
Emission Factors
Emissions of pollutants other than benzene from byproduct recovery plants have
been investigated fairly extensively in support of Federal rule development. Values of total POM
are available; however, little attempt has been made to speciate POM fully. This is due first to
the recognition that, once again, the composition of POM is variable, and second to the finding
that because so much of the POM emissions is naphthalene, the remaining species could be
considered insignificant (VanOsdell et al., 1979).
4-399
-------
It should be noted that naphthalene is the only constituent of POM that is a
commercially desirable chemical product. As such, emissions of naphthalene resulting from its
production and use are discussed separately in Section 5.0 of this document. The principal
method of producing naphthalene is in the coke byproduct recovery step of coke production; the
naphthalene recovery portion of the coke byproduct recovery operation is described in greater
detail in Section 5.0.
Finally, the 1989 benzene NESHAP required full implementation by three years
from promulgation, so it can be assumed that data collected previously to support regulatory
development no longer reflect the reduced emissions from this source today. Hence, no emission
factors are presented for this portion of the byproduct coking process other than the naphthalene
emission factors presented in Section 5.0. Overall, before promulgation of the 1989 benzene
NESHAP, emissions of POM from the byproduct recovery process were estimated to be 23 tpy
(21 Mg/yr). The estimated impact of the 1989 NESHAP is a reduction in benzene emissions of
93 percent and a reduction in overall VOC, including POM of 96 percent (U.S. EPA, 1988).
Source Locations
All of the coke oven plants listed in Table 4.7-5 are designed to recover coke
byproducts and have byproduct recovery plants co-located with them. In 1994 there was one
nonrecovery plant operating in the U.S. (in Vansant, Virginia). As the name implies, this process
does not recover the numerous chemical byproducts as discussed in the previous section. All of
the coke oven gas is burned, and instead of recovery of chemicals, this process offers the
potential for heat recovery and cogeneration of electricity. The plant that is currently operating
does not have waste heat recovery; however, any new construction of this process at integrated
iron and steel plants is expected to take advantage of the economic incentives of recovering the
waste heat (U.S. EPA, 1995).
4400
-------
SECTION 4.7 REFERENCES
Federal Register. National Emission Standards for Hazardous Air Pollutants; Benzene
Emissions from Maleic Anhydride Plants, Ethylbenzene/Styrene Plants, Benzene Storage
Vessels, Benzene Equipment Leaks, and Coke By-Product Recovery Plants. Volume 54,
No. 177, p. 38044 (54 FR 38044) September 14, 1989.
International Agency for Research on Cancer (IARC). Volume 34: Polynuclear Aromatic
Compounds. Part 3. Industrial Exposures in Aluminum Production. Coal Gasification. Coke
Production, and Iron and Steel Founding. IARC Press, 150 cours Albert Thomas, F-69372 Lyon
Cedex 08, France. ISBN 92 832 15346. 1984.
Johnson, N.D. et al. MOE Toxic Chemical Emissions Inventory for Ontario and Eastern North
America. Prepared for the Air Resources Branch, Ontario Ministry of the Environment, Rexdale,
Ontario. Draft Report No. P.89-50-5429/OG. 1990.
Kelly, M.E. Sources and Emissions of Polycyclic Organic Matter. U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina. EPA-450/5-83-010b. 1983.
Kirton, P.J., J. Ellis, and P.T. Crisp. "The Analysis of Organic Matter in Coke Oven Emissions."
Fuel, Volume 70, pp. 1383-1389. 1991.
Laube, A.H., and B.A. Drummond. Coke Quench Tower Emission Testing Program (DraftV
Prepared for Industrial Environmental Research Laboratory, U.S. Environmental Protection
Agency, Research Triangle Park, North Carolina. EPA Contract No. 68-02-2819. 1979.
Trenholm, A.R., and L.L. Beck. Assessment of Hazardous Organic Emissions from Slot Type
Coke Oven Batteries. U.S. Environmental Protection Agency, Emission Standards and
Engineering Division, Research Triangle Park, North Carolina. 1978.
U.S. Environmental Protection Agency. Compilation of Air Pollution Emission Factors - AP-42.
Draft Section 12.2: Coke Production. 1995.
U.S. Environmental Protection Agency. Benzene Emissions from Coke Byproduct Recovery
Plants - Background Information for Revised Proposed Standards. Office of Air Quality
Planning and Standards, Research Triangle Park, North Carolina. EPA-450/3-83-016b. 1988.
U.S. Environmental Protection Agency. Coke Oven Emissions from Wet-Coal Charged
Byproduct Coke Oven Batteries - Background Information for Proposed Standards. Office of Air
Quality Planning and Standards, Research Triangle Park, North Carolina. EPA-450/3-85-028a.
April 1987.
U.S. Environmental Protection Agency. Benzene Emissions from Coke Byproduct Recovery
Plants - Background Information for Proposed Standards. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. EPA-450/3-83-016a. May 1984.
4-401
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VanOsdell, D.W., D. Marsland, B.H. Carpenter, C. Sparacino, and R. Jablin. Environmental
Assessment of Coke Byproduct Recovery Plants. Industrial Environmental Research Laboratory,
U.S. Environmental Protection Agency, Research Triangle Park, North Carolina. EPA-600/2-79-
016. 1979.
4-402
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4.8 PORTLAND CEMENT MANUFACTURING
Most of the hydraulic cement produced in the United States is portland cement, a
crystalline compound composed of metallic oxides. Raw materials used in the process can be
limestone that contains calcium carbonate and aluminum, iron, and silicon oxides, shale, clay,
and sand (U.S. EPA, 1995). There are four primary components in portland cement
manufacturing: raw materials handling, kiln feed preparation, pyroprocessing, and finished
cement grinding. Pyroprocessing, the fuel-intensive process accomplished in cement kilns, has
been identified as a potential source of POM emissions, and constitutes the primary focus of this
chapter.
Process Description
Typically, most raw materials used in portland cement manufacturing are quarried
on site and transferred by conveyor to crushers and raw mills. After the raw materials are
reduced to the desired particle size, they are blended and fed to a large rotary kiln (RTI, 1994).
There are five variations in portland cement manufacturing: wet, dry, semidry,
dry with a preheater, and dry preheater/precalciner processes. These processes are essentially
identical in their raw materials and end product. However, the type of process does affect the
equipment design, method of operation, and fuel consumption. In the first three, all fuel
combustion occurs in the kiln. In the latter two, some fuel combustion occurs in a precalcining
or calcining vessel before the materials enter the kiln.
In general, fuel consumption decreases in the order of the processes listed above.
The preheater/precalciner equipment uses less fuel and requires a shorter kiln, and the wet
process uses the most fuel and requires the longest kiln, but the relationship is not linear
(U.S. EPA, 1995). Many older kilns use the wet process; in the past, wet grinding and mixing
technologies provided more uniform and consistent material mixing, resulting in a higher quality
clinker. Technologies have improved, however, to the point that all of the new kilns since 1975
use the dry process (U.S. EPA, 1991).
4-403
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The kiln system for the manufacture of portland cement by dry process with
preheater is shown in Figure 4.8-1. The raw material enters a four-stage suspension preheater,
where hot gases from the kiln heat the raw feed and provide about 40 percent calcination
(Stream 1) before the feed enters the kiln. Some installations include a precalcining furnace
(Stream 2), which provides about 85 percent calcination before the feed enters the kiln
(U.S. EPA, 1995).
The feed enters the kiln at the elevated end, and the burner is located at the
opposite end. The raw materials are then changed into cementitious oxides of metal by a
countercurrent heat exchange process. The materials are continuously and slowly moved to the
low end by the rotation of the kiln while being heated to temperatures of approximately 2,700 °F
(1,480°C) by direct firing (Stream 3). In this stage, chemical reactions occur, and a rock-like
substance called "clinker" is formed. This clinker is then cooled, crushed, and blended with
gypsum to produce portland cement (U.S. EPA, 1995). The cement is then either bagged or
bulk-loaded and transported out (RTI, 1994).
Portland cement production is a fuel-intensive process. The fuel burned in the
kiln may be natural gas, oil, or coal. Many cement plants burn coal, but supplemental fuels such
as waste solvents, chipped rubber or tire-derived fuel (TDF), shredded municipal garbage, and
coke have been used in recent years (U.S. EPA, 1995). A major trend in the industry is the
increased use of hazardous waste-derived fuels (HWDFs). In 1989, 33 plants in the
United States and Canada reported using waste fuels; that number increased to 55 plants in 1990
(U.S. EPA, 1995).
The increased use of HWDFs is attributed to lower cost and increased availability.
As waste generators reduce or eliminate solvents from their waste steams, the streams will
contain more sludge and solids.
4-404
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Hot Gases to
Roller Mill
Fan
Clinker Storage
Source: U.S. EPA, 1995.
Figure 4.8-1. Process Diagram of Portland Cement Manufacturing
by Dry Process with Preheater
-------
Facilities that burn HWDFs are subject to the Boilers and Industrial Furnaces
(BIF) rule under the Resource Conservation and Recovery Act (RCRA) promulgated
February 21, 1991. The BIF rule requires that a facility that burns hazardous waste demonstrate a
99.99-percent destruction efficiency for principal organic hazardous constituents in the waste
stream. To guard against products of incomplete combustion, the BIF rule limits CO levels in
the kiln or total hydrocarbon levels in the stack gases (Kim, 1994; U.S. EPA, 1994). Maximum
achievable control technology (MACT) Standards are being developed for BIFs under the joint
authority of RCRA and the Clean Air Act (CAA). The MACT Standards will apply to the
following three BIF source categories: hazardous waste incinerators, cement kilns that burn
hazardous waste, and light weight aggregate kilns that burn hazardous waste (Behan
Telecon, 1995).
Emission Factors
The raw materials used by some facilities may contain organic compounds and
thus be the source of POM emissions during the heating step. However, fuel combustion to heat
the kiln is believed to be the primary source of POM emissions. The data collected and
presented in this chapter indicate that POM is emitted from portland cement kilns firing fossil
fuels, waste fuels, HWDFs, and combinations of the above (U.S. EPA, 1995; U.S. EPA, 1994).
PAH emissions data for portland cement kilns with various process, fuel, and
control configurations were compiled by the Office of Solid Waste (OSW) in 1994 and the
Office of Air Quality Planning and Standards (OAQPS) in 1991 and 1994 (U.S. EPA, 1994;
U.S. EPA, 1991; U.S. EPA, 1995). The OSW document reports results of tests conducted at
35 portland cement manufacturing facilities to certify compliance with the BIF rule. PAH
emission factors were derived from the OSW report when sufficient emissions and process
information were available. Emission factors were presented in the two additional EPA reports
based on test data from two individual facilities (U.S.EPA, 1991; U.S. EPA, 1995).
4-406
-------
Wet process cement kiln PAH emission factors are presented in
Tables 4.8-1 through 4.8-8. Table 4.8-1 lists emission factors from a coal/liquid and solid
hazardous waste-fired cement kiln equipped with an electrostatic precipitator (ESP). During
testing, the kiln was operated at low combustion temperature and high hazardous waste feed.
Table 4.8-2 contains emission factors from a coal/coke/liquid and solid hazardous waste-fired
cement kiln equipped with ESP. During testing, the kiln was operated at high combustion
temperature and high hazardous waste feed. Table 4.8-3 lists emission factors from a liquid and
solid waste-fired cement kiln equipped with an ESP and operated at low combustion temperature
and high hazardous waste feed.
Table 4.8-4 lists emission factors from a natural gas/hazardous waste-fired cement
kiln equipped with an ESP and operated at low combustion temperature. Table 4.8-5 contains
emission factors from a coal/coke-fired cement kiln equipped with an ESP and operated at high
combustion temperature. Table 4.8-6 contains emission factors from a coal/coke/liquid
hazardous waste-fired cement kiln equipped with an ESP and operated a low combustion
temperature with high hazardous waste feed. Tables 4.8-7 and 4.8-8 list emission factors from a
single ESP-equipped cement kiln under two fuel scenarios: 100 percent coal firing and
14 percent TDF/86 percent coal firing, respectively.
Dry and dry precalciner process cement kiln PAH emission factors are presented
in Tables 4.8-9 through 4.8-12. Table 4.8-9 lists emission factors for a coal/coke/liquid and solid
hazardous waste-fired dry process cement kiln equipped with an ESP and operated at low
combustion temperature and high hazardous waste feed. Table 4.8-10 lists emission factors from
a coke/hazardous waste-fired dry process cement kiln equipped with a multiclyclone and ESP in
series and operated at high combustion temperature and high hazardous waste feed. Table 4.8-11
lists emission factors from a coal/hazardous waste-fired dry process cement kiln equipped with a
fabric filter. Table 4.8-12 contains emission factors from a coal-fired dry precalciner process
cement kiln equipped with a fabric filter.
4-407
-------
TABLE 4.8-1. PAH EMISSION FACTORS FOR COAL/HAZARDOUS WASTE-FIRED
WET PROCESS PORTLAND CEMENT KILNS
oo
SCC Number Emission Source" Control Device Pollutant
3-05-007-6 Wet Process Cement Kiln Electrostatic Precipitator Benz(a)anthracene
Benzo(b)fluoranthene
Chrysene
Acenaphthylene
Fluorene
Fluoranthene
Naphthalene
Phenanthrene
Pyrene
2-Methylnaphthalene
Average Emission
Factor in Ib/ton
(kg/Mg)b
3.23E-05
(1.62E-05)
4.65E-05
(2.33E-05)
6.79E-05
(3.39E-05)
3.45E-04
(1.73E-04)
3.88E-05
(1.94E-05)
2.22E-04
(1.11E-04)
9.07E-04
(4.53E-04)
3.44E-04
(1.72E-04)
6.95E-04
(3.47E-04)
7.13E-05
(3.56E-05)
Emission '
Factor
Rating
D
D
D
D
D
D
D
D
D
D
"Kiln operating conditions: low combustion temperature; high liquid and solid hazardous waste feed.
bEmission factors are in Ib/kg of pollutant emitted per ton (Mg) of clinker produced.
Source: U.S. EPA, 1994.
-------
TABLE 4.8-2. PAH EMISSION FACTORS FOR COAL/COKE/HAZARDOUS WASTE-FIRED
WET PROCESS PORTLAND CEMENT KILNS
SCC Number Emission Source1 Control Device Pollutant
3-05-007-6 Wet Process Cement Kiln Electrostatic Precipitator Benzo(b)fluoranthene
Chrysene
Acenaphthylene
Anthracene
Fluorene
Fluoranthene
Naphthalene
Phenanthrene
Pyrene
2-Methylnaphthalene
Average Emission
Factor in Ib/ton
(kg/Mg)b
1.33E-05
(6.67E-06)
5.85E-06
(2.92E-06)
2.59E-04
(1.30E-04)
1.76E-05
(8.81E-06)
2.22E-05
(1.11E-05)
1.33E-04
(6.66E-05)
8.22E-04
(4.11E-04)
2.26E-04
(1.13E-04)
7.55E-05
(3.78E-05)
7.07E-05
(3.54E-05)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
aKiln operating conditions: low combustion temperature; high liquid and solid hazardous waste feed.
bEmission factors are in Ib (kg) of pollutant emitted per ton (Mg) of clinker produced.
Source: U.S. EPA, 1994.
-------
TABLE 4.8-3. PAH EMISSION FACTORS FOR HAZARDOUS WASTE-FIRED
WET PROCESS PORTLAND CEMENT KILNS
t
SCC Number Emission Source8 Control Device Pollutant
3-05-007-6 Wet Process Cement Kiln Electrostatic Precipitator Acenaphthylene
Fluoranthene
Naphthalene
Phenanthrene
Pyrene
2-Methylnaphlhalene
Average Emission
Factor in Ib/ton
(kg/Mg)b
3.76E-05
(1.88E-05)
3.10E-05
(1.55E-05)
8.01 E-04
(4.01 E-04)
1.71 E-04
(8.54E-05)
2.18E-05
(1.09E-05)
1.68E-04
(8.39E-05)
Emission
Factor
Rating
C
C
C
C
C
C
'Kiln operating conditions: low combustion temperature; high liquid and solid hazardous waste feed.
bEmission factors are in Ib (kg) of pollutant emitted per ton (Mg) of clinker produced.
Source: U.S. EPA, 1994.
-------
TABLE 4.8-4. PAH EMISSION FACTORS FOR GAS/HAZARDOUS WASTE-FIRED
WET PROCESS PORTLAND CEMENT KILNS
SCC Number Emission Source4 Control Device Pollutant
3-05-007-6 Wet Process Cement Kiln Electrostatic Precipitator Acenaphthylene
Anthracene
Fluorene
Fluoranthene
Naphthalene
Phenanthrene
Pyrene
2-Methylnaphthalene
Average Emission
Factor in Ib/ton
(kg/Mg)b
1.20E-04
(6.02E-05)
5.92E-06
(2.96E-06)
4.66E-06
(2.33E-06)
3.99E-05
(1.99E-05)
7.28E-04
(3.64E-04)
1.45E-04
(7.26E-05)
3.07E-05
(1.53E-05)
6.42E-04
(3.21E-04)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
"Kiln operating conditions: low combustion temperature; liquid and solid hazardous waste firing.
''Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of clinker produced.
Source: U.S. EPA, 1994.
-------
TABLE 4.8-5. PAH EMISSION FACTORS FOR COAL/COKE-FIRED WET PROCESS PORTLAND CEMENT KILNS
SCC Number Emission Source* Control Device Pollutant
3-05-007-6 Wet Process Cement Kiln Electrostatic Precipitator Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluorene
Fluoranthene
Average Emission
Factor in Ib/ton
(kg/Mg)b
7.24E-05
(3.62E-05)
2.73E-05
(1.37E-05)
3.21E-06
(1.61E-06)
1.32E-04
(6.61E-05)
3.21E-06
(1.61E-06)
4.51E-06
(2.25E-06)
7.84E-05
(3.92E-05)
5.18E-04
(2.59E-04)
1.63E-04
(8.16E-05)
3.21E-06
(1.61E-06)
3.02E-04
(1.51E-04)
2.17E-04
(1.09E-04)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.8-5. (Continued)
SCC Number Emission Source* Control Device
3-05-007-6 Wet Process Cement Kiln Electrostatic Precipitator
(continued) (continued) (continued)
Pollutant
Naphthalene
Phenanthrene
Pyrene
2-Methylnaphthalene
Average Emission
Factor in Ib/ton
(kg/Mg)b
9.66E-04
(4.83E-04)
6.01 E-04
(3.01 E-04)
1.61 E-04
(8.06E-05)
1.01E-03
(5.05E-04)
Emission
Factor
Rating
D
D
D
D
aKiln operating conditions: high combustion temperature.
Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of raw material slurry input.
Source: U.S. EPA, 1994.
4-
h-^
U)
-------
TABLE 4.8-6. PAH EMISSION FACTORS FOR COAL/COKE/HAZARDOUS WASTE-FIRED
WET PROCESS PORTLAND CEMENT KILNS
SCC Number Emission Source" Control Device Pollutant
3-05-007-6 Wet Process Cement Kiln Electrostatic Precipitator Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluorene
Fluoranthene
Average Emission
Factor in Ib/ton
(kg/Mg)b
1.56E-04
(7.80E-05)
7.92E-05
(3.96E-05)
4.61E-05
(2.30E-05)
2.76E-04
(1.38E-04)
1.43E-05
(7.13E-06)
1.74E-05
(8.68E-06)
1.24E-04
(6.18E-05)
8.32E-04
(4.16E-04)
3.21E-04
(1.60E-04)
3.33E-05
(1.67E-05)
9.51E-04
(4.75E-04)
3.49E-04
(1.74E-04)
Emission-
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.8-6. (Continued)
SCC Number Emission Source1 Control Device
3-05-007-6 Wet Process Cement Kiln Electrostatic Precipitator
(continued) (continued) (continued)
Pollutant
Naphthalene
Phenanthrene
Pyrene
2-MethyInaphthalene
Average Emission
Factor in Ib/ton
(kg/Mg)b
9.99E-04
(5.00E-04)
9.07E-04
(4.54E-04)
1.24E-04
(6.20E-05)
1.19E-03
(5.94E-04)
Emission
Factor
Rating
D
D
D
D
aKiln operating conditions: low combustion temperature; liquid hazardous waste feed.
bEmission factors are in Ib (kg) of pollutant emitted per ton (Mg) of raw material slurry input.
Source: U.S. EPA, 1994.
in
-------
TABLE 4.8-7. PAH EMISSION FACTORS FOR COAL-FIRED WET PROCESS PORTLAND CEMENT KILNS
SCC Number Emission Source Control Device Pollutant
3-05-007-6 Wet Process Cement Kiln Electrostatic Precipitator Benzo(a)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Fluorene
Naphthalene
Pyrene
Benz(b)anthracene
Dibenz(g,h)anthracene
Average Emission
Factor in Ib/MMBtu
(g/MJ)a
2.04E-06
(8.77E-07)
2.76E-06
(1.19E-06)
2.20E-07
(9.46E-08)
2.46E-06
(1.06E-06)
7.65E-06
(3.29E-06)
3.40E-04
(1.46E-04)
4.97E-06
(2.14E-06)
9.88E-06
(4.25E-06)
1.07E-04
(4.59E-05)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
"Emission factors are in Ib (g) of pollutant emitted per MMBtu (MJ) of heat input.
Source: U.S. EPA, 1991.
-------
TABLE 4.8-8. PAH EMISSION FACTORS FOR COAL/TDF-FIRED WET PROCESS PORTLAND CEMENT KILNS
SCC Number Emission Source3 Control Device Pollutant
3-05-007-6 Wet Process Cement Kiln Electrostatic Precipitator Acenaphthene
Benzo(ghi)perylene
Fluorene
Naphthalene
Pyrene
Dibenz(g,h)anthracene
Average Emission
Factor in Ib/MMBtu
(g/MJ)b
2.06E-06
(8.86E-07)
1.03E-05
(4.44E-06)
7.12E-06
(3.06E-06)
1.59E-04
(6.84E-05)
2.23E-06
(9.59E-07)
6.72E-05
(2.89E-05)
Emission
Factor
Rating
D
D
D
D
D
D
'Kiln fuel scenario: 86 percent coal - 14 percent tire derived fuel (TDF).
Emission factors are in Ib (g) of pollutant emitted per MMBtu (MJ) of heat input.
Source: U.S. EPA, 1991.
-------
TABLE 4.8-9. PAH EMISSION FACTORS FOR COAL/COKE/HAZARDOUS WASTE-FIRED
DRY PROCESS PORTLAND CEMENT KILNS
oo
SCC Number Emission Source* Control Device Pollutant
3-05-006-6 Dry Process Cement Kiln Electrostatic Precipitator Acenaphthene
Fluorene
Fluoranthene
Naphthalene
Phenanthrene
Pyrene
2-MethyInaphthalene
Average Emission
Factor in Ib/ton
(kg/Mg)b
1.80E-05
(8.99E-06)
2.77E-06
(1.39E-06)
4.84E-06
(2.42E-06)
3.84E-04
(1.92E-04)
3.37E-05
(1.69E-05)
2.91E-06
(1.46E-06)
4.11E-05
(2.06E-05)
Emission
Factor
Rating
D
D
D
D
D
D
D
"Kiln operating conditions: low combustion temperature; high liquid and solid hazardous waste feed.
''Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of clinker produced.
Source: U.S. EPA, 1994.
-------
TABLE 4.8-10. PAH EMISSION FACTORS FOR COKE/HAZARDOUS WASTE-FIRED
DRY PROCESS PORTLAND CEMENT KILNS
SCC Number Emission Source8 Control Device
3-05-006-6 Dry Process Cement Kiln Multicyclone/Electrostatic
Precipitator
Pollutant
Naphthalene
Phenanthrene
Average Emission
Factor in Ib/ton
(kg/Mg)b
1.25E-10
(6.27E-11)
1.54E-11
(7.69E-12)
Emission
Factor
Rating
D
D
"Kiln operating conditions: high combustion temperature; high liquid hazardous waste feed.
bEmission factors are in Ib (kg) of pollutant emitted per ton (Mg) of solid raw material input.
Source: U.S. EPA, 1994.
-------
TABLE 4.8-11. PAH EMISSION FACTORS FOR COAL/HAZARDOUS WASTE-FIRED
DRY PROCESS PORTLAND CEMENT KILNS
SCC Number Emission Source Control Device Pollutant
3-05-006-6 Dry Process Cement Kiln Fabric Filter Acenaphthene
Acenaphthylene
Fluorene
Fluoranthene
Naphthalene
Phenanthrene
2-Methylnaphthalene
Average Emission
Factor in Ib/ton
(kg/Mg)a
1.88E-06
(9.40E-07)
3.99E-06
(1.99E-06)
<1.12E-06
(<5.62E-07)
2.43E-06
(1.22E-06)
<1.30E-04
(<6.49E-05)
1.56E-05
(7.79E-06)
3.60E-05
(1.80E-05)
Emission
Factor Rating
D
D
D
D
D
D
D
"Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of solid raw material input.
Source: U.S. EPA, 1994.
-------
TABLE 4.8-12. PAH EMISSION FACTORS FOR COAL-FIRED PRECALCINER
DRY PROCESS PORTLAND CEMENT KILNS
t
to
SCC Number Emission Source Control Device Pollutant
3-05-006-6 Dry Process Cement Kiln Fabric Filter Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno(l ,2,3-cd)pyrene
Acenaphthene
Benzo(ghi)perylene
Fluorene
Fluoranthene
Naphthalene
Average Emission
Factor in Ib/ton
(kg/Mg)a
4.3E-08
(2.1E-08)
1.3E-07
(6.5E-08)
5.6E-07
(2.8E-07)
1.5E-07
(7.7E-08)
1.6E-07
(8.1E-08)
6.3E-07
(3.1E-07)
8.7E-08
(4.3E-08)
1.2E-04
(5.9E-05)
7.8E-08
(3.9E-08)
1.9E-05
(9.4E-06)
8.8E-06
(4.4E-06)
1.7E-03
f8.5E-04)
Emission
Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.8-12. (Continued)
SCC Number
3-05-006-6
(continued)
Emission Source Control Device
Dry Process Cement Kiln Fabric Filter (continued)
(continued)
Pollutant
Phenanthrene
Pyrene
Average Emission
Factor in Ib/ton
(kg/Mg)a
3.9E-04
(2.0E-04)
4.4E-06
(2.2E-06)
Emission
Factor
Rating
E
E
"Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of raw material input.
Source: U.S. EPA, 1994.
to
-------
Source Locations
The portland cement manufacturing industry is dispersed geographically
throughout the United States. Thirty-six States have at least one facility. As of December 1990,
there were 119 known portland cement plants operating in the United States, operating 214 kilns
with a total annual clinker capacity of 81 x 106 tons (73.7 x 106 Mg). The kiln population
included 80 wet process kilns and 133 dry process kilns (U.S. EPA, 1995). Table 4.8-13 presents
the number of portland cement plants and kilns in the United States by state and the associated
production capacities as of December 1990.
4-423
-------
TABLE 4.8-13. U.S. PORTLAND CEMENT PLANT
LOCATIONS AND CAPACITY
Location
Alabama
Alaska
Arizona
Arkansas
California
Colorado
Florida
Georgia
Hawaii
Idaho
Illinois
Indiana
Iowa
Kansas
Kentucky
Maine
Maryland
Michigan
Mississippi
Missouri
Montana
Nebraska
Nevada
New Mexico
New York
Ohio
Number of Plants
(kilns)
5(6)
K0)a
2(7)
2(5)
12 (20)
3(5)
6(8)
2(4)
KD
1(2)
4(8)
4(8)
4(7)
4(11)
KD
KD
3(7)
5(9)
KD
5(7)
2(2)
1(2)
1(2)
1(2)
4(5)
4(5)
Capacity
103tons/vr(103Mg/yr)
4,260 (3,873)
0(0)
1,770(1,609)
1,314(1,195)
10,392 (9,447)
1,804(1,640)
3,363 (3,057)
1,378(1,253)
263 (239)
210(191)
2,585 (2,350)
2,830 (2,573)
2,806(2,551)
1,888(1,716)
724 (658)
455 (414)
1,860(1,691)
4,898 (4,453)
504 (458)
4,677 (4,252)
592 (538)
961 (874)
415 (377)
494 (449)
3,097 (2,815)
1,703(1,548)
4-424
(continued)
-------
TABLE 4.8-13. (Continued)
Location
Oklahoma
Oregon
Pennsylvania
South Carolina
South Dakota
Tennessee
Texas
Utah
Virginia
Washington
West Virginia
Wyoming
"Grinding plant only.
Source: U.S. EPA, 1995.
Number of Plants
(kilns)
3(7)
KD
11(24)
3(7)
1(3)
2(3)
12 (20)
2(3)
1(5)
KD
1(3)
KD
Capacity
103 tons/yr (103 Mg/yr)
1,887(1,715)
480 (436)
6,643 (6,039)
2,579 (2,345)
766 (696)
1,050(955)
8,587 (7,806)
928 (844)
1,117(1,015)
473 (430)
822 (747)
461 (419)
4-425
(continued)
-------
SECTION 4.8 REFERENCES
Behan, Frank, U.S. Environmental Protection Agency, telephone conversation with Peter Keller,
Radian Corporation. "Proposed MACT Standards for BIFs." September 13,1995.
Kim, I. "Incinerators and Cement Kilns Face Off." Chemical Engineering. April 1994.
Research Triangle Institute (RTI). Deliverable for Task 1, Work Assignment 2-39, EPA Contract
68-D2-0065. Prepared for U.S. Environmental Protection Agency, Office of Air Quality
Planning and Standards, Research Triangle Park, North Carolina. 1994.
U.S. Environmental Protection Agency. Compilation of Air Pollutant Emissions Factors.
Volume I: Stationary Point and Area Sources. AP-42, Fifth Edition, Section 11.6: Portland
Cement Manufacturing. Office of Air Quality Planning and Standards, Research Triangle Park,
North Carolina. 1995.
U.S. Environmental Protection Agency. Technical Support for Revision of the Hazardous Waste
Combustion Regulations for Cement Kilns and Other Thermal Treatment Devices. Second Draft.
Prepared by Energy and Environmental Research Corporation for Office of Solid Waste. Work
Assignment 1-10. 1994.
U.S. Environmental Protection Agency. Burning Tires for Fuel and Tire Pyrolysis: Air
Implications. Office of Air Quality Planning and Standards, Research Triangle Park, North
Carolina. EPA/450-3-91-024, pp. 4-1 to 4-37. December 1991.
4-426
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4.9 PULP AND PAPER INDUSTRY
Chemical wood pulping involves the extraction of cellulose from wood by
dissolving the lignin that binds the cellulose fibers. Kraft pulping is the major form of chemical
wood pulping in the United States, accounting for approximately 85 percent of pulp production
(U.S. EPA, 1993), and is expected to continue as the dominant pulping process (AWMA, 1992;
Dyer et al., 1992). Semi-chemical and acid sulfite pulping constitute 6 and 4 percent of domestic
pulp production, respectively (U.S. EPA, 1993).
Three combustion processes associated with the pulp and paper industry have
been identified as potential sources of POM emissions: chemical recovery furnaces, lime kilns,
and power boilers. Wood waste and fossil fuel-fired industrial power boiler POM emissions are
discussed in Section 4.1.2 because these sources are not specific to the pulp and paper industry.
The following sections focus on the pulp mill chemical recovery processes associated with
potential POM emissions.
4.9.1 Kraft Recovery Furnaces
Process Description
The Kraft pulping process involves the cooking or digesting of wood chips at an
elevated temperature 340 to 360°F (about 175°C) and pressure (100 to 135 psig) in white liquor,
which is a water solution of sodium sulfide (Na2S) and sodium hydroxide (NaOH). The lignin
that binds the cellulose fibers is chemically dissolved by the white liquor in a tall, vertical
digester. This process breaks the wood into soluble lignin and alkali-soluble hemicellulose and
insoluble cellulose or pulp. A typical Kraft pulping and recovery process is shown in
Figure 4.9.1-1.
Two types of digester systems are used in chemical pulping: batch and
continuous. In a batch digester, the contents of the digester are transferred to an atmospheric
tank, usually referred to as a blow tank, after cooking is completed (2 to 6 hours). In a
4-427
-------
POTENTIAL
EMISSIONS
CHIPS
RELIEF
i,
HEAT
EXCHANGER
NONCONDENSABLES
, t ,. .
t
to
oo
TURPENTINE
CONTAMINATED WATER
STEAM, CONTAMINATED WATER
OXIDATION
TOWER
CONTAMINATED
-*• WATER
AIR
PULP
ON
R
1 .
m
3
1
so
L _
BLACK LIQUOR
50* SOLIDS
DIRECT CONTACT
EVAPORATOR
1 (^
r
n
i
WATER
•«••
RECOVERY
FURNACE
OXIDIZING
ZONE
REDUCTION
ZONE
SMELT
NI2S + NI2C03
AIR
Figure 4.9.1-1. Typical Kraft Pulping and Recovery Process
I
\
\
Source: U.S. EPA, 1995.
-------
continuous digester, wood chips and white liquor continuously enter the system from the top
while pulp is continuously withdrawn from the bottom into a blow tank. In both types of
digesters, the entire contents of the blow tank are diluted and pumped to a series of brown-stock
washers, where the spent cooking liquor is separated from the pulp. The pulp, which may then
be bleached, is pressed and dried into the finished product.
The balance of the Kraft process is designed to recover the cooking chemicals and
heat. The diluted spent cooking liquor, or weak black liquor, which is 12 to 18 percent dissolved
solids, is extracted from the brownstock washers and concentrated in a multiple-effect evaporator
system to about 55 percent solids. The liquor is then further concentrated to 65 percent solids
(strong black liquor) in a direct contact evaporator (DCE) or a nondirect contact evaporator
(NDCE), depending on the configuration of the recovery furnace in which the liquor is
combusted. DCE and NDCE recovery furnace schematics are shown in Figures 4.9.1-2 and
4.9.1-3, respectively.
In older recovery furnaces, the furnace's hot combustion gases concentrate the
black liquor in a DCE prior to combustion. NDCEs include most furnaces built since the early
1970s and modified older furnaces that have incorporated recovery systems that eliminate the
conventional DCEs. These NDCEs use a concentrator rather than a DCE to concentrate the
black liquor prior to combustion. In another type of NDCE system, the multiple-effect
evaporator system is extended to replace the direct contact system.
The strong black liquor is sprayed into a recovery furnace with air control to
create both reducing and oxidizing zones within the furnace chamber. The combustion of the
organics dissolved in the black liquor provides heat for generating process steam and, more
importantly, for reducing sodium sulfate (Na2SO4) to Na2S to be reused in the cooking process.
Sodium sulfate, which constitutes the bulk of the particulates in the furnace flue gas, is recovered
and recycled by an ESP. During combustion, most of the inorganic chemicals present in the
black liquor collect as a molten smelt in the form of sodium carbonate (Na2CO3) and N^S at the
bottom of the furnace, where they are continuously withdrawn into a smelt-dissolving tank.
4-429
-------
Stack
Electrostatic
Precipitator
£
o
Air
i v_
Recovery Boiler
Combustion Gas
60-70% Solids
Direct Contact
Evaporator
Smelt
Black Liquor
50% Solids
Figure 4.9.1-2. Direct Contact Evaporator Recovery Boiler
Source: Radian, 1993.
-------
UJ
Air—•+-{
I \_
Recovery Boiler
Smelt
Combustion Gas
Steam
Electrostatic
Precipitator
72% Solids
I
Indirect Contact
Evaporator
Black Liquor
50% Solids
Figure 4.9.1-3. Non-direct Contact Evaporator Recovery Boiler
Source: Radian, 1993.
-------
In addition to straight Kraft process liquor, semi-chemical pulping process spent
liquor, known as brown liquor, may also be recovered in Kraft recovery furnaces. The
semi-chemical pulping process is a combination of chemical and mechanical pulping processes
that was developed to produce high-yield chemical pulps. In the semi-chemical process, wood
chips are partially digested with cooking chemicals to weaken the bonds between the lignin and
the wood. Oversize particles are removed from the softened wood chips and the chips are
mechanically reduced to pulp by grinding them in a refiner. The most common type of
semi-chemical pulping is referred to as neutral sulfite semi-chemical (NSSC). The only major
difference between the semi-chemical process and Kraft/sulfite pulping process is that the
semi-chemical digestion process is shorter and wood chips are only partially delignified. As
mentioned above, some mills combine spent liquor from on-site semi-chemical processes with
spent liquor from adjacent Kraft processes for cross-chemical recovery (U.S. EPA, 1993).
Stand-alone, semi-chemical mills mostly recover chemicals from liquor using fluidized bed
incineration or reactors, such as a Copeland reactor.
Particulate emissions from the Kraft recovery furnaces consist primarily of
sodium sulfate and sodium carbonate, with some sodium chloride. Particulate control on NDCE
recovery furnaces is achieved with ESPs, including both wet- and dry-bottom, and, to a lesser
extent, with scrubbers. For DCEs equipped with either a cyclonic scrubber or a cascade
evaporator, further particulate control is necessary because these devices are generally only 20 to
50 percent efficient for particulates (U.S. EPA, 1995). Most often in these cases, an ESP is
employed after the DCE for an overall particulate control efficiency range of 85 percent to more
than 99 percent. At existing mills, auxiliary scrubbers may be added to supplement older and
less efficient primary particulate control devices. No specific data were available in the literature
documenting POM control efficiencies for ESPs and scrubbers on Kraft black liquor recovery
furnaces.
POM compound emissions from black liquor combustion are affected by furnace
emission control devices as well as recovery process operating characteristics, furnace design and
operation, and the characteristics of the black liquor feed. Furnace design and operation affect
combustion efficiency, which is inversely related to POM emissions. The black liquor
4-432
-------
concentration process determines the percentage of organic and inorganic solids in the black
liquor feed. Higher percent solids liquors which contain a greater concentration of organic
compounds will exhibit better combustion properties due to the higher heating value of the
liquor.
Emission Factors
Emission factors for PAHs from three Kraft recovery furnace/control
configurations were reported by the National Council for Air and Stream Improvement, an
industry environmental research organization (NCASI, 1993). The three furnace/control
configurations represented included a DCE recovery furnace equipped with a wet-bottom ESP
and scrubber in series, an NDCE recovery furnace equipped with a dry-bottom ESP, and an
NDCE recovery furnace equipped with a dry-bottom ESP and wet scrubber in series. Sampling
was conducted for 16 PAHs using CARB Method 429. The resultant controlled emission factors
represent both vapor-phase and particulate PAHs and are expressed in units of pound of PAH per
air dry ton of pulp produced (Ib/ADTP) and kilogram of PAH per air dry metric ton of pulp
produced (kg/ADMT). The black liquor solids (BLS) fired in a Kraft recovery boiler can be
correlated to ADTP by a factor of approximately 3,000 Ib of BLS per ADTP (NCASI, 1993).
PAH emission factors for Kraft black liquor recovery furnaces are presented in Table 4.9.1-1.
Source Locations
The distribution of Kraft pulp mills in the United States in 1993 is shown in
Table 4.9.1-2. Kraft pulp mills are located primarily in the southeast, whose forests provide over
60 percent of U.S. pulpwood.
4-433
-------
TABLE 4.9.1-1. PAH EMISSION FACTORS FOR KRAFT PROCESS RECOVERY FURNACES
u>
SCC Number Emission Source
3-07-001-04 Nondirect-Contact
Evaporator Kraft
Recovery Furnace
3-07-001-04 Direct-Contact
Evaporator Kraft
Recovery Furnace
3-07-001-04 Direct-Contact
Evaporator Kraft
Recovery Furnace
Control Device Pollutant
Dry-Bottom ESP Benz(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-cd )pyrene
Acenaphthene
Benzo(ghi)perylene
Pyrene
Wet-Bottom ESP Naphthalene
Wet-Bottom Benz(a)anthracene
ESP/Scrubber
Benzo(a)pyrene
Emission Factor
Average Emission Factor Range in Ib/ADTP
in Ib/ADTP (kg/ADMT)a (kg/ADMT)a
<1.20E-05
(<6.00E-06)
<2.60E-06
(<1.30E-06)
<6.40E-06
(<3.20E-06)
5.50E-05
(2.75E-05)
<6.00E-06
(<3.00E-06)
<6.00E-06
(<3.00E-06)
<5.00E-06
(<2.50E-06)
7.90E-06
(3.59E-06)
l.OOE-04
(5.00E-05)
5.95E-03 3.3E-3 - 8.6E-3
(2.98E-03) ( 1 .7E-3 - 4.3E-3)
9.60E-05
(4.80E-05)
5.80E-06
(2.90E-06)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.9.1-1. (Continued)
.
h
SCC Number Emission Source Control Device Pollutant
3-07-001-04 Direct-Contact Wet-Bottom Benzo(b)fluoranthene
(continued) Evaporator Kraft ESP/Scrubber
Recovery Furnace (continued)
(continued)
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno(l ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Fluorene
Naphthalene
Emission Factor
Average Emission Factor Range in Ib/ADTP
in Ib/ADTP (kg/ADMT)a (kg/ADMT)a
2.90E-05
(1.45E-05)
8.00E-06
(4.00E-06)
3.90E-05
(1.95E-05)
6.80E-06
(3.40E-06)
4.20E-06
(2.10E-06)
1.60E-05
(8.00E-06)
2.60E-03
(1.30E-03)
4.00E-04
(2.00E-04)
1.20E-05
(6.00E-06)
6.90E-04
(3.45E-04)
2.10E-04
(1.05E-04)
3.20E-02
(1.60E-02)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.9.1 -1. (Continued)
ON
SCC Number Emission Source Control Device Pollutant
3-07-001-04 Direct-Contact Wet-Bottom Phenanthrene
(continued) Evaporator Kraft ESP/Scrubber
Recovery Furnace (continued)
(continued)
Pyrene
3-07-001-10 Indirect-Contact Dry-Bottom Naphthalene
Evaporator Kraft ESP/Scrubber
Recovery Furnace
Benz(a)anthraccne
Benzo(a)pyrenc
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno( 1 ,2,3-ccJ)pyrene
Acenaphthene
Acenaphthylene
Emission Factor
Average Emission Factor Range in Ib/ADTP
in Ib/ADTP (kg/ADMT)a (kg/ADMT)a
5.60E-03
(2.80E-03)
3.30E-04
(1.65E-04)
8.70E-04
(4.35E-04)
<3.50E-06
(<1.75E-06)
<3.50E-06
(<1.75E-06)
<3.50E-06
(<1.75E-06)
<3.50E-06
(<1.75E-06)
<3.50E-06
(<1.75E-06)
<3.50E-06
(1.75E-06)
<3.50E-06
(<1.75E-06)
<3.50E-06
(<1.75E-06)
1.30E-05
(6.50E-06)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.9.1 -1. (Continued)
Emission Factor
Average Emission Factor Range in Ib/ADTP
SCC Number Emission Source Control Device Pollutant in Ib/ADTP (kg/ADMT)a (kg/ADMT)a
3-07-001-10 Indirect-Contact Wet-Bottom Anthracene <3.50E-06
(continued) Evaporator Kraft ESP/Scrubber (<1.75E-06)
Recovery Furnace (continued)
(continued)
Benzo(ghi)perylcne <3.50E-06
(<1.75E-06)
Fluoranthene 1 .90E-05
(9.50E-06)
Fluorene <3.50E-06
(<1.75E-06)
Phenanthrene 9.50E-05
(4.75E-05)
Pyrene 1.10E-05
(5.50E-06)
Emission
Factor
Rating
D
D
D
D
D
D
"Emission factors are in Ib (kg) of pollutant emitted per ADTP (ADMT) of pulp produced.
Source: NCASI, 1993.
-------
TABLE 4.9.1-2. DISTRIBUTION OF KRAFT PULP MILLS IN THE
UNITED STATES (1993)
State
Alabama
Arizona
Arkansas
California
Florida
Georgia
Idaho
Kentucky
Louisiana
Maine
Maryland
Michigan
Minnesota
Mississippi
Montana
New Hampshire
New York
North Carolina
Ohio
Oklahoma
Oregon
Pennsylvania
South Carolina
Number of Mills
16
2
7
3
11
13
1
2
11
8
1
3
3
5
2
2
1
7
1
1
7
4
6
(continued)
4-438
-------
TABLE 4.9.1-2. (Continued)
State Number of Mills
Tennessee 3
Texas 8
Virginia 5
Washington 12
Wisconsin 4
Total 149
Source: U.S. EPA, 1993.
4-439
-------
4.9.2 Lime Kilns
Process Description
In the Kraft pulping process, molten smelt leaving the recovery furnace is
contacted with mill water or weak wash in the smelt dissolving tank to form green liquor. Weak
wash is the filtrate from lime mud washing. The green liquor is clarified and reacted with burnt
lime (CaO) in a lime slaker. Following a series of causticizing vessels, the resultant white liquor
is clarified to yield Na2S + NaOH (aqueous white liquor) and lime mud or calcium carbonate
(CaCO3). The white liquor is recycled to the digestion process and the lime mud is calcined in a
lime kiln to regenerate CaO (Radian, 1993).
A lime kiln is a countercurrent, inclined tube process heater designed to convert
lime mud (CaCO3) to CaO for reuse in the causticizing of Kraft liquor. A process flow diagram
for a lime kiln is shown in Figure 4.9.2-1. The rotary kiln is the most common lime kiln design
used in the Kraft pulp and paper industry. Rotary lime kilns range from 8 to 13 feet (2.4 to
4.0 m) in diameter, and from 100 to 400 feet (30 to 120 m) in length. Lime kilns predominantly
fire natural gas, with some units firing distillate and/or residual fuel oil. Many facilities
incinerate non-condensible gases (NCG) from pulping source vents in lime kilns to control total
reduced sulfur (TRS) emissions. Temperatures in the kiln can range from 300 to 500°F (150 to
260°C) at the upper or wet end to 2,200 to 2,400°F (1,200 1,300°C) at the hottest part of the
calcination zone near the lower or dry end (U.S. EPA, 1976; Radian, 1993).
Emissions of concern from lime kilns include PM, largely in the form of calcium
salts, SO2, NOX, and organics from either water evaporated from the lime mud in the kiln or the
scrubbing medium employed. Emissions of POM from lime kilns are likely due almost entirely
to the combustion of fossil fuel (natural gas or fuel oil). The most common control technologies
used on lime kilns are scrubbers, although some ESPs are also used. Scrubbers are used on lime
kilns primarily for control of paniculate emissions. These scrubbers use either fresh water or
clean condensates from pulping sources as scrubbing solutions. Small amounts of caustic
solution may be added to the scrubber solution to scrub TRS and SO2. Lime kiln scrubber
4-440
-------
Potential
Emissions
Figure 4.9.2-1. Process Flow Diagram for a Lime Kiln
Source: Radian, 1993.
-------
designs include impingement, venturi, and cyclonic scrubbers. Scrubbers and ESPs can provide
control of particulate POM emissions. Additionally, wet scrubbers may provide some control of
vapor-phase POM by condensation and solution in the scrubbing medium (NCASI, 1993).
Emission Factors
PAH emission factors for two scrubber-controlled lime kilns under four fuel firing
scenarios are presented in Table 4.9.2-1. The scenarios include natural gas, natural gas/coke,
natural gas/NCG, and natural gas/tire-derived fuel (TDF). The data reported by NCASI (1993)
were based on sampling and analysis for naphthalene only. The sampling methods used were
CARB Method 429 and EPA Reference Method 18. The emission factors reported by EPA
(1991) were based on an unspecified sampling protocol that was assumed to conform with
EPA-approved methodology.
Source Locations
Lime kilns are located at Kraft process pulp mills. See Table 4.9.1-2
Section 4.9.1 for Kraft pulp mill source locations reported in 1993.
4.9.3 Sulfite Recovery Furnaces
Process Description
Although not as commonplace, the acid sulfite pulp production process is similar
to the Kraft process except that different chemicals are used for cooking. Sulfurous acid is used
in place of a caustic solution to dissolve wood lignin. To buffer the cooking solution, a bisulfite
of sodium, magnesium, calcium, or ammonium is used. Digestion occurs under high temperature
and pressure, as in the Kraft process, in either batch mode or continuous digesters. Following
digestion and discharge of the pulp into an atmospheric blow pit or dump tank, the spent sulfite
liquor, known as red liquor, may be treated and discarded, incinerated, or sent through a recovery
4-442
-------
TABLE 4.9.2-1. PAH EMISSION FACTORS FOR PULP MILL LIME KILNS
Control
SCC Number Emission Source Device Pollutant
3-07-001-06 Gas-Fired Lime Kiln Scrubber Benz(a)anthracene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Anthracene
Fluoranthene
Naphthalene
Phenanthrene
Pyrene
3-07-001-06 Gas-/TDF-Fired Lime Kilnc Scrubber Benz(a)anthracene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Average Emission
Factor in Ib/MMBtu
(g/MJ)a
1.10E-06
(4.73E-07)
8.00E-07
(3.44E-07)
3.00E-07
(1.29E-07)
1.10E-06
(4.73-07)
3.70E-06
(1.59E-06)
8.60E-06
(3.70E-06)
0.036
(0.01 8)b
5.19E-05
(2.23E-05)
6.60E-06
(2.84E-06)
1.10E-06
(4.73E-07)
8.00E-07
(3.44E-07)
4.00E-07
(1.72E-07)
1.10E-06
(4.73E-07)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
D
Reference
U.S. EPA, 1991
U.S. EPA, 1991
U.S. EPA, 1991
U.S. EPA, 1991
U.S. EPA, 1991
U.S. EPA, 1991
NCASI, 1993
U.S. EPA, 1991
U.S. EPA, 1991
U.S. EPA, 1991
U.S. EPA, 1991
U.S. EPA, 1991
U.S. EPA, 1991
(continued)
-------
TABLE 4.9.2-1. (Continued)
Control
SCC Number Emission Source Device
3-07-001-06 Gas-/TDF-Fired Lime Kilnc Scrubber
(continued) (continued) (continued)
3-07-001-06 Gas-Fired Lime Kiln Burning Scrubber
NCGd
3-07-001-06 Gas-/Coke-Fired Lime Kiln Scrubber
Pollutant
Anthracene
Fluoranthene
Phenanthrene
Pyrene
Naphthalene
Naphthalene
Average Emission
Factor in Ib/MMBtu
(g/MJ)a
1.80E-06
(7.74E-07)
8.80E-06
(3.78E-06)
2.91E-05
(1.25E-05)
6.20E-06
(2.67E-06)
6.50E-03
(3.25E-03)b
4.60E-03
(2.30E-03)b
Emission
Factor
Rating
D
D
D
D
D
D
Reference
U.S. EPA, 1991
U.S. EPA, 1991
U.S. EPA, 1991
NCASI, 1993
NCASI, 1993
NCASI, 1993
"Emission factors are in Ib (g) of pollutant emitted per MMBtu (MJ) of heat input, except as noted.
''Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of calcium oxide produced.
^ime kiln firing 85 percent natural gas and 15 percent TDF.
NCD from pulping and chemical recovery operations are incinerated in the lime kiln to reduce total reduced sulfur (TRS) emissions to the atmosphere.
-------
process for recovery of heat and chemicals. Additionally, chemicals can be recovered from
gaseous streams such as those from red stock washers. The cost of the soluble bases, with the
exception of calcium, makes chemical recovery economically feasible (U.S. EPA, 1995;
U.S. EPA, 1993). A simplified process schematic of magnesium-base sulfite pulping and
chemical recovery is shown in Figure 4.9.3-1.
Emission Factors
Only one PAH emission factor was available in the literature for naphthalene from
an uncontrolled ammonia-base sulfite recovery furnace. The naphthalene emission factor is
presented in Table 4.9.3-1.
Source Locations
Sulfite recovery furnaces are located at sulfite process pulp mills. Table 4.9.3-2
shows the distribution of sulfite pulp mills in the United States in 1993 according to information
compiled in support of EPA's pulp and paper industry MACT standard development.
4-445
-------
Wood
Chips
A
Digester
UJ.
T^
V
Tank
iUSt
-M5M
1 Dump 1
,-J Tank J
Poti
E
Recov
Absor
E
Digester
Relief
D^
i— i Add
ly) ™»
r~T~l
Cooking f
Add
Storage I
Hot Water
i^
\ Pulp Washers Screens
J -^P
-0 . I_ J
0
CH 1
Weak
Red
Liquor
sntlal POM
missions
ery Furnace/
>tlon Stream
ixhaust
Evaporative
I • hxh8U5t Mnrhanlcal . . Staamfor
l_ 1 Dust 1 Process
r*~l I ' 1 Collector I
1 11 1 1 Recovery v / — t-i
1*1 Direct-Contact Furnace \ oil
V"/ Evaporator Exhaust [ \~~r " ^Sjl
n -^^*^. I I mi QO
A h P °°
1 — ij, .. \7 N r
Absorotlbn MgO T J I1- *^ \
\ \ S^^ \
V rr^L 1 —
L^-yO J ^ I
1 " S S | Mg(OH) 2| Mg(OH)2
Water strong Red Liquor
Makeup
\ ru-i — u^ifur f^
L i 1 [ 1 Multiple-Effect
— ' < — • Sulftir Evaporators
Gas Burner Strong I I
Uquor * ~ '"•"'
Storage |
1
Condensate
Unbleached
Pulp
Storage
Weak Red Liquor
i and Power
Recovery Furnace
1
Liquor <>
Heater
-------
TABLE 4.9.3-1. PAH EMISSION FACTORS FOR SULFTTE PROCESS RECOVERY FURNACES
Emission
Average Emission Factor in Factor
SCC Number Emission Source Control Device Pollutant Ib/ADTP (kg/ADMT)a Rating
3-07-002-22 Ammonia-Based Sulfite None Naphthalene 4.30E-03 D
Recovery Furnace (2.15E-03)
"Emission factor is in Ib (kg) of naphthalene emitted per ADTP (ADMT) of pulp produced.
Source: NCASI, 1993.
-------
TABLE 4.9.3-2. DISTRIBUTION OF SULFTTE PULP MILLS IN THE
UNITED STATES (1993)
State
Alaska
Florida
Maine
New York
Pennsylvania
Washington
Wisconsin
Total
Number of Mills
2
1
1
1
1
5
5
16
Source: U.S. EPA, 1993.
4-448
-------
SECTION 4.9 REFERENCES
Air and Waste Management Association (AWMA). Air Pollution Engineering Manual.
Chapter 18, "Wood Processing Industry." Van Nostrand Reinhold, New York. 1992.
Dyer, H., S. Gajita, and M. Fennessey. 1992 Lockwood-Post's Directory of the Pulp. Paper and
Allied Trades. Miller Freeman Publications, San Francisco, California. 1992.
National Council of the Paper Industry for Air and Stream Improvement (NCASI). "Compilation
of Air Toxic Emission Data for Boilers, Pulp Mills, and Bleach Plants." NCASI Inc., 260
Madison Avenue, New York, New York. Technical Bulletin No. 650, pp. 1-17 and 71-106.
June 1993.
Radian Corporation. "Pulp and Paper Industry Training Session Notes." 1993.
U.S. Environmental Protection Agency. Compilation of Air Pollution Emission Factors - AP-42
Section 10.2: Chemical Wood Pulping. Fifth Edition. Research Triangle Park, North Carolina.
1995.
U.S. Environmental Protection Agency. Pulp. Paper, and Paperboard Industry -Background
Information for Proposed Air Emission Standards: Manufacturing Processes at Kraft. Sulfite.
Soda, and Semi-Chemical Mills. Emission Standards Division, Office of Air Quality Planning
and Standards, Research Triangle Park, North Carolina. EPA-453/R-93-050a. pp. 2-1 to 2-22.
1993.
U.S. Environmental Protection Agency, Burning Tires for Fuel and Tire Pyrolysis: Air
Implications. Office of Air Quality Planning and Standards, Research Triangle Park,
North Carolina. EPA/450-3-91-024, pp. 4-1 to 4-37. 1991.
U.S. Environmental Protection Agency. Environmental Pollution Control - Pulp and Paper
Industry. Part 1: Air. Emission Standards Division, Research Triangle Park, North Carolina.
EPA-625/7-76-001. pp. 11-1 to 11-11. October 1976.
U.S. Environmental Protection Agency. Pulp. Paper, and Paperboard Industry -Background
Information for Promulgated Air Emission Standards: Manufacturing Processes at Kraft. Sulfite.
Soda. Semi-Chemical Mills. Mechanical, and Secondary and Non-wood Fiber Mills. Emission
Standards Division, Office of Air Quality Planning and Standards, Research Triangle Park, North
Carolina. EPA-453/R-93-050b. p. 20-5. 1997.
4-449
-------
4.10 OPEN BURNING
Open burning, for the purposes of this document, includes wildfires, prescribed
burning (including agricultural burning and burning associated with forest management), burning
of landscaping refuse, coal refuse burning, and controlled open burning of tires and plastic. The
activity associated with each of these source categories can vary greatly from year to year
depending on natural conditions, as in the case of wildfires, or on user practices. All of these
sources, however, have been associated with POM emissions through laboratory or field
emissions tests. The main source of emissions is the combustion of the particular fuel material
(i.e., the live vegetation or dead organic material).
4.10.1 Wildfires and Prescribed Burning
Process Description
Wildfires refer to uncontrolled forest fires, whereas prescribed burning involves
the operation and management of a controlled burn of timber or agricultural vegetation and
debris. The basic process in both that results in POM emissions is very similar. Both of these
sources often involve incomplete combustion of the fuel (i.e., the wood, leaves, etc.) due to the
high moisture content, of the fuel varying composition of the fuel, and the limited control of the
combustion process.
The most important fuel characteristics affecting emissions from wildfires and
prescribed burning are fuel moisture content and fuel loading (i.e., amount of fuel per unit area).
Fuel arrangement and fuel species composition (i.e., fuel type, fuel age, and fuel size) are also
key variables affecting emissions. High moisture content reduces combustion efficiency, which
in turn produces greater emissions. Fuel loading level is directly related to emissions, the more
fuel burned, the greater the emissions. Fuel arrangement can affect burn intensity and
completeness by affecting air supply and may influence the fire spreading pattern.
4-450
-------
Fuel composition affects emissions in several ways. Different fuels (wood, grass,
brush, leaves) have varying compositions, which upon combustion, produce different qualities
and quantities of emissions. Fuels of differing ages contain varying moisture contents (seasoned
versus green fuels) and varying organic constituents which may affect overall burning emissions.
Emissions may also be affected if fuel composition has been modified by organic forest treatment
chemicals such as pesticides, herbicides, etc. (Chi et al., 1979; McMahon and Tsoukalas, 1978).
Following is a brief description of wildfires and prescribed burning and their main
emission characteristics.
Wildfires—Wildfires naturally occur from lightning strikes or can be accidently or intentionally
started by humans. These fires tend to spread unpredictably and are often times out of control.
Emissions from uncontrolled forest fires are affected primarily by environmental factors and fuel
conditions. The most prominent environmental factors influencing emissions are wind speed and
direction, rainfall history, and relative humidity. Secondary environmental factors include degree
of cloud cover, air temperature, atmospheric stability, and degree of land slope. Wind speed,
wind direction, and, to a lesser extent, slope of land all determine how fast a wildfire will spread.
Generally, a faster moving fire front burns less efficiently, producing more smoldering and
greater emissions (Chi et al., 1979).
Prescribed Burning—For this report prescribed burning is defined as the application and
confinement of fire under specified conditions of weather, fuel moisture and soil moisture in a
forest, or range, or for agricultural land management. Prescribed burning should accomplish
planned benefits such as fire hazard reduction, control of understory species, seedbed and site
preparation, grazing enhancement, wildlife habitat improvement, or forest tree disease control. It
differs from uncontrolled wildfires in that it is used only under controlled conditions and is
managed so that beneficial effects outweigh possible detrimental impacts.
Agricultural burning involves the purposeful combustion of field crop, row crop,
and fruit and nut crop residues to achieve one or a combination of desired objectives. The typical
objectives of agricultural burning are as follows (Kelly, 1983; Chi and Zanders, 1977).
4-451
-------
• Removal and disposal of agricultural residue at a low cost;
• Preparation of farmlands for cultivation;
• Cleaning of vines and leaves from fields to facilitate harvest
operations;
• Disease control;
• Direct weed control by incinerating weed plants and weed seeds;
• Indirect weed control by providing clean soil surface for soil-active
herbicides; and
• Selective destruction of mites, insects, and rodents.
The types of agricultural waste subject to burning include residues such as rice
straw and stubble; barley straw and stubble; wheat residues; prunings and natural attrition losses
in orchards; grass straw and stubble; potato and peanut vines; tobacco stalks; soybean residues;
hay residues; sugarcane leaves and tops; and farmland grass and weeds.
Polycyclic organic matter is created and emitted during agricultural burning due to
POM mixing between the fuel (agricultural residue) and ambient air, and because combustion
gases are effectively quenched by surrounding ambient air. Poor mixing creates pyrolytic
(oxygen deficient) combustion conditions leading to lower temperatures, less efficient
combustion, and POM formation and release. Rapid quenching of combustion gases by the huge
volumes of air surrounding agricultural burning enhances incomplete combustion, thereby
permitting the increased release of unburned hydrocarbons like POM. Polycyclic organic matter
may be released from agricultural burning in gaseous form or as a liquid aerosol condensed on
solid particulate matter (Kelly, 1983; Chi and Zanders, 1977).
When prescribed burning is used, emissions control and/or emissions impact
reduction can be effected by utilizing low emission fuel conditions, firing techniques, and
meteorological conditions. Fuel conditions can be optimized and overall POM emissions
reduced by:
4-452
-------
• Regulating the time between burns to control fuel loading;
• Burning at lower fuel moisture contents; and
• Modifying fuel arrangement to facilitate better air flow and more
intense and complete combustion.
The firing techniques involved in forest management and agricultural burning can vary widely
depending on the specific plant species, the local climate, and any applicable regulations that
may be in effect.
Emission Factors
Limited amounts of POM emission factor data were found that are based on tests
of actual prescribed burning or uncontrolled forest fires. However, emission factor data have
been developed by the U.S. Forest Service by simulating forest burning conditions in a
laboratory. In one test, various loadings of pine needles were burned on a metal table equipped
to change slope to simulate wind effects (McMahon and Tsoukalas, 1978). All emissions from
burning were channeled through a large stack where particulate matter was collected on a glass
fiber filter in a modified high-volume sampler. Collected samples were analyzed for POM
compounds by GC/MS. The results of these tests are given in Table 4.10.1-1.
The PAH emission factors that are based on the study by McMahon and
Tsoukalas are presented in Table 4.10.1-1 and represent the average emissions during the flaming
and smoldering phases of a fire. The factors could conceivably be used for either estimating
emissions from wildfires or prescribed burning of pine trees material. These factors should not
be considered to be representative of burning in hardwood forests or areas where the vegetation
is more varied.
Table 4.10.1-1 also presents a set of PAH emission factors that represent both
wildfires and prescribed burning (forest and agricultural), with no specific vegetation type
identified (Versar Inc., 1989). These factors are also based on laboratory testing conditions, and
4-453
-------
TABLE 4.10.1-1. PAH EMISSION FACTORS FOR WILDFIRES AND PRESCRIBED BURNING
SCC Number Emission Source Control Device Pollutant
A28-10-001-000/ Forest Wildfires/ None Benzo(a)pyrene
A28-10-010-000 Slash, Prescribed
Burning (from the
burning of pine
needles)
Benzofluoranthenes
Chrysene/Renz(a)anthracene
Indeno( 1 ,2 , 3-cd)pyrene
Benzo(ghi)perylene
Anthracene/Phenanthrene
Fluoranthene
Pyrene
Benzo(e)pyrene
Methylanthracene
Perylene
Benzo(c)phenanthrene
Average Emission
Factor in Ib/ton
(mg/kR)a
1.48E-03
(0.74)
5.14E-03
(2.57)
1.27E-02
(6.32)
3.41E-03
(1.70)
5.08E-03
(2-54)
9.95E03
(4.96)
6.73E-03
(3.36)
9.29E-03
(4.64)
2.66E-03
(1.33)
8.23E-03
(4.10)
8.56E-04
(0.43)
3.90E-03
(1.95)
Emission
Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
Reference
McMahon and Tsoukalas, 1978
McMahon and Tsoukalas, 1978
McMahon and Tsoukalas, 1978
McMahon and Tsoukalas, 1978
McMahon and Tsoukalas, 1978
McMahon and Tsoukalas, 1978
McMahon and Tsoukalas, 1978
McMahon and Tsoukalas, 1978
McMahon and Tsoukalas, 1978
McMahon and Tsoukalas, 1978
McMahon and Tsoukalas, 1978
McMahon and Tsoukalas, 1978
(continued)
-------
TABLE 4.10.1-1. (Continued)
Lft
SCC Number
A28- 10-001 -0007
A28- 10-0 10-000
(continued)
A28- 10-00 1-0007
A28- 10-0 10-0007
A28-0 1-500-000
Emission Source
Forest Wildfires/Slash,
Prescribed Burning (from
the burning of pine
needles) (continued)
Forest Wildfires/Slash,
Prescribed Burning/
Agricultural Burning
(exact source unspecified)
Control Device Pollutant
None Methylbenzopyrenes
Methylchryscne
Methylpyrene, -fluoranthene
None Benz(a)anthracene
Benzo(a)pyrcne
Benzo(k)fluoranthene
Chrysene
Indeno( 1 ,2,3-cd)pyrene
Benzo(ghi)pcrylene
Anthracene
Fluoranthene
Average Emission
Factor in Ih/ton
(mg/kg)a
2.96E-03
(1.48)
7.90E-03
(3.94)
9.05E-03
(4.52)
6.20E-03
(3.09)
1.50E-03
(0.75)
2.60E-03
(1.30)
6.20E-03
(3.09)
2.40E-03
(1.20)
5.00E-03
(2.49)
5.00E-03
(2-49)
1.10E-02
(5.49)
Emission
Factor
Rating
E
E
E
U
U
U
U
U
U
U
U
Reference
McMahon and Tsoukalas, 1978
McMahon and Tsoukalas, 1978
McMahon and Tsoukalas, 1978
Versar, Inc., 1989
Versar, Inc., 1989
Versar, Inc., 1989
Versar, Inc., 1989
Versar, Inc., 1989
Versar, Inc., 1989
Versar, Inc., 1989
Versar, Inc., 1989
(continued)
-------
TABLE 4.10.1-1. (Continued)
SCC Number
A28- 10-001-0007
A28-10-010-0007
A28-0 1-500-000
(continued)
A28-10-010-000
A28-0 1-500-000
Emission Source Control Device Pollutant
Forest Wildfires/Slash, None Phenanthrene
Prescribed Burning/
Agricultural Burning
(exact source unspecified)
(continued)
Pyrene
Benzo(a)fluoranthene
Slash, Prescribed Burning None Benzo(a)pyrene
(Temperate and Boreal
Forest)
Burning Sugar Cane None Benzo(a)pyrene
(Whole Cane and Leaf
Trash)
Average Emission
Factor in Ib/ton
(mg/kg)a
5.00E-03
(2.49)
9.20E-03
(4.59)
2.60E-03
(1.30)
4.49E-04
(0.22)
4.75E-04
(0.24)
Emission
Factor
Rating
U
U
U
D
E
Reference
Versar, Inc., 1989
Versar, Inc., 1989
Versar, Inc., 1989
Ward and Hao, 1992
Chi and Zanders, 1977
Ul
o\
"Emission factors are expressed in Ib (mg) of pollutant per ton (kg) of fuel (wood, brush, vegetation, etc.) burned.
-------
therefore will not necessarily represent the wide range of combustion conditions that would be
experienced in the field.
The factor listed for benzo(a)pyrene for slash/prescribed burning, which is based
on the Ward and Hao, 1992 document, was developed from actual field test data in combination
with laboratory research. The field tests were conducted in forest areas in the States of
Washington and Oregon. A total of 38 fires were studied, involving a variety of fuel types and
burning conditions. The benzo(a)pyrene factor listed is representative of temperate forests that
would typically be found in many areas of the United States.
Few POM emission factors exist that are specific to agricultural burning. The
factors that are available pertain only to benzo(a)pyrene. Burning of whole sugar cane residue
and sugar cane leaf trash were found to produce paniculate emissions of benzo(a)pyrene (Chi and
Zanders, 1977). Agricultural burning has received significant attention due to the proximity of
burning to human population areas.
Source Locations
Information provided by the U.S. Forest Service indicates that the majority of
prescribed burning in the United States occurs in the southern/southeastern part of the country
(Cruse, 1986). Sixty percent of national prescribed burning in 1984 was performed in the
southern/southeastern region. The second most prevalent source of prescribed burning in 1984
was the Pacific Northwest which constituted almost 20 percent of the total; California
contributed 10 percent of the national total (U.S. Forest Service, 1986).
Peterson and Ward, compiled an estimate of the area burned by prescription
in 1989 for the entire United States. The total area burned for the United States was over
4.9 million acres (2 million hectares). The authors estimated that the number of hectares burned
nationally during 1989 that were reported in their study may have been underestimated by a half
a million hectares (Peterson and Ward, 1989).
4-457
-------
Peterson and Ward also estimated the amount of acreage burned in different
regions of the country. Their findings agreed with the conclusions of the U.S. Forest Service that
are presented above; namely, that the majority (71 percent) of prescribed burning occurs in the
southern/southeastern part of the United States. The states identified being in the
southern/southeastern part of the United States include Alabama, Florida, Georgia, Kentucky,
Mississippi, North Carolina, South Carolina, and Tennessee.
The locations of uncontrolled forest fires are not as definable as prescribed
burning sites, but the historical record of fires and a knowledge of the locations of primary forest
resources can be used to estimate where the majority of forest fires are likely to occur. The
southern region and the western part of the country (including California, the Pacific northwest,
and western mountain states) appear to represent the greatest potential for POM emissions from
forest wildfires (Siebert et al., 1978). Forest Service data for 1983 indicate that the
southern/southeastern region of the United States constituted 67 percent of the total number of
acres burned by wildfires nationally. The western regions of the country contained 17 percent of
the wildfire burned acreage. The northern region (Idaho, Montana, North Dakota) of the country
contained another 6 percent of acreage destroyed by wildfires (U.S. Forest Service, 1986).
Agricultural burning is directly correlated significant agriculture industry. Major
agricultural states comprising the majority of agricultural burning include California, Louisiana,
Florida, Hawaii, North Carolina, Mississippi, and Kansas (Kelly, 1983).
4-458
-------
SECTION 4.10.1 REFERENCES
Chi, C.T. et al. Source Assessment: Prescribed Burning. State of the Art. U.S. Environmental
Protection Agency, Industrial Environmental Research Laboratory, Research Triangle Park,
North Carolina. EPA Report No. 600/2-79-019h. November 1979.
Chi, C.T., and D.L. Zanders. Source Assessment: Agricultural Open Burning. State of the Art.
U.S. Environmental Protection Agency, Industrial Environmental Research Laboratory, Research
Triangle Park, North Carolina. EPA Report No. 600/2-77-107a. July 1977.
Kelly, M.E. Sources and Emissions of Polvcyclic Organic Matter. U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina. EPA Report No. 450/5-83-010b.
pp. 5-3 to 5-9. 1983.
McMahon, C.K., and S.N. Tsoukalas. "Polynuclear Aromatic Hydrocarbons in Forest Fire
Smoke." In: Polynuclear Aromatic Hydrocarbons: Analysis. Chemistry, and Biology.
Proceedings of the Second International Symposium on Polynuclear Aromatic Hydrocarbons,
Columbus, Ohio, 1977. P.W. Jones and R.I. Freudenthal, eds. Raven Press, New York.
pp. 61-73. 1978.
Peterson, J., and D. Ward. An Inventory of Particulate Matter and Air Toxics Emissions from
Prescribed Fires in the United States for 1989. Pacific Northwest Research Station, Seattle,
Washington. Final Report. USDA Forest Service Technical Report AG No. DW12934736-01-
0-1989. 1992.
Siebert, P.C. et al. Preliminary Assessment of the Sources. Control and Population Exposure to
Airborne Polvcyclic Organic Matter (POM) as Indicated by Benzofalpyrene (BaPX
U.S. Environmental Protection Agency, Pollutant Strategies Branch, Office of Air Quality
Planning and Standards, Research Triangle Park, North Carolina. Prepared under EPA Contract
No. 68-02-2836. pp. 99-102. November 1978.
U.S. Forest Service. Information submitted to Cruse, P.A., Radian Corporation by Hansen, K.,
Forest Service Reports on Wildfire Statistics for 1978 to 1983. June 23, 1986.
Versar, Inc. Procedures for Estimating and Allocating Area Source Emissions of Air Toxics.
Springfield, Virginia, p. 7-3. March 1989.
Ward, D., and Wei Min Hao. "Air Toxic Emissions from Burning of Biomass Globally:
Preliminary Estimates," USDA Forest Service, Missoula, Montana. Presented at the 85th Annual
Meeting and Exhibition of the Air and Waste Management Association, Kansas City, Missouri.
June 21-26, 1992.
4-459
-------
4.10.2 Open Burning of Scrap Tires
Process Description
Approximately 240 million vehicle tires are discarded annually (Lemieux and
Ryan, 1993). Although viable methods for recycling exist, less than 25 percent of discarded tires
are recycled; the remaining 175 million are discarded in landfills, stockpiles, or illegal dumps
(Lemieux and Ryan, 1993). Although it is illegal in many states to dispose of tires using open
burning, fires often occur at tire stockpiles and through illegal burning activities. It is estimated
that approximately 7.5 million tires burn each year in landfills and illegal dumps in the United
States (U.S. EPA, 1998). These fires generate a huge amount of heat and are difficult to
extinguish; some tire fires continue for months. POM is emitted from these fires as a result of
the incomplete combustion of the scrap tires.
Emission Factors
Table 4.10.2-1 contains emission factors for the open burning of tires
(U.S. EPA, 1993). The average emission factor presented represents the average of tests
performed on the simulated open burning of chunk and shredded tires. When estimating
emissions from an accidental tire fire, it should be kept in mind that emissions from burning tires
are generally dependent on the burn rate of the tire. A greater potential for emissions exists at
lower burn rates, such as when a tire is smoldering rather than burning out of control
(U.S. EPA, 1993). The fact that the shredded tires have a lower burn rate than whole tires
indicates that the gaps between tire materials provide the major avenue of oxygen transport.
Oxygen transport appears to be a major, if not the controlling mechanism for sustaining the
combustion process (Lemieux and Ryan, 1993).
4-460
-------
TABLE 4.10.2-1. PAH EMISSION FACTORS FOR OPEN BURNING OF SCRAP TIRES
SCC Number Emission Source Control Device Pollutant
5-03-002-03 Simulated Open Burning None Benz(a)anthracenc
of Chunk and Shredded
Scrap Tires
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Dibenz(a,h)anthracene
Indeno(l ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Benzo(ghi)perylene
Anthracene
Fluoranthene
Average Emission
Factor in
lb/1, 000 tons tire
(mg/kg tire)a
111.62
(55.81)
288.96
(144.48)
272.17
(136.09)
382.04
(191.02)
143.13
(71.57)
54.50
(27.25)
144.98
(72.49)
3103.80
(1,551.90)
1138.29
(569.14)
197.04
(98.52)
315.22
(157.61)
505.65
(252.83)
Emission Factor Range in
lb/1, 000 tons tire
(mg/kg tire)
15.80 - 207.43
(7.90-103.71)
230.32 - 347.60
(115.16- 173.80)
178.14-366.20
(89.07- 183.10)
200.48 - 563.60
(100.24-281.80)
96.60- 189.65
(48.30 - 94.83)
0.00- 109.00
(20.00 - 54.50)
117.20- 172.76
(58.60 - 86.38)
1,436.40-4,771.20
(718.20-2,385.60)
1,136.17-1,140.40
(568.08 - 570.20)
72.40-321.68
(36.20- 160.84)
99.23-531.20
(49.61-265.60)
84.60 - 926.69
(42.30 - 463.35)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.10.2-1. (Continued)
Average Emission
Factor in
Ib/ 1,000 tons tire
SCC Number Emission Source Control Device Pollutant (mg/kg tire)a
5-03-002-03 Simulated Open Burning None Fluorene 232.89
(continued) of Chunk and Shredded ( 1 1 6.45)
Scrap Tires (continued)
Naphthalene 490.85
(245.43)
Phenanthrene 280.73
(140.37)
Pyrene 188.69
(94.35)
Emission Factor Range in
lb/1, 000 tons tire
(mg/kg tire)
86.80 - 378.98
(43.40- 189.49)
0.00-981.69
(0.00 - 490.85)
56.00 - 505.46
(28.00 - 252.73)
70.40 - 306.98
(35.20 - 153.49)
Emission
Factor
Rating
D
D
D
D
aEmission factors are in expressed Ib (mg) of pollutant per 1,000 tons (kg) of fuel burned.
Source: U.S. EPA, 1993.
4^
O\
-------
Source Location
Open burning of scrap tires can occur at permitted landfills that stockpile scrap
tires, at closed landfills that already contain scrap tires, and at illegal dumpsites where tires are
discarded. The fires can start by accident or by arson, and it is unpredictable as to where and
when they will occur.
4-463
-------
SECTION 4.10.2 REFERENCES
Lemieux, P. M., and J. V. Ryan. "Characterization of Air Pollutants Emitted from a Simulated
Scrap Tire Fire." Journal of the Air and Waste Management Association, Volume 43, pp. 1106-
1115. August 1993.
U.S. Environmental Protection Agency. 1990 Emission Inventory of Section 1I2(c)(6)
Pollutants: Polycvclic Organic Matter (POM). 2.3.7.8-Tetrachlorodibenzo-p-Dioxin
(TCDDV2.3.7.8-Tetrachlorodibenzofuran (TCDF). Polychlorinated Biphenyl Compounds
(PCBsX Hexachlorobenzene. Mercury, and Alkylated Lead. Emission Factor and Inventory
Group, Research Triangle Park, North Carolina. Final Report. March 1998.
U.S. Environmental Protection Agency. Supplement F to Compilation of Air Pollutant Emission
Factors. Volume I: Stationary Point and Area Sources. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. AP-42, Volume I, Supplement F. pp. 2.4-2
and 2.4-4. July 1993.
4-464
-------
4.10.3 Agricultural Plastic Film Burning
Process Description
Large quantities of plastic film are commonly used for mulching, weed control,
and to retain ground moisture in crop fields. When the crop residue is burned, the plastic film is
also combusted. The plastic film is likely to be a combination of new or unused plastic
(i.e., plastic that was not actually covering or underneath the crops or soil) and used plastic,
which contains a high moisture and vegetation content. Each type of plastic burns differently.
Used plastic is more difficult to ignite and burns at a much slower rate than new plastic. New or
unused plastic is highly combustible and melts quickly to form a liquid pool that burns from the
surface. Burning usually occurs in the crop row where the plastic is used or in large piles in the
field where the plastic is collected (Linak et al., 1989).
Emission Factors
Table 4.10.3-1 presents PAH emission factors for the burning of agricultural
plastic film (U.S. EPA, 1993). Factors are presented for two types of burning conditions. One
set of factors is based on the plastic being gathered into a pile and burned. The second set of
factors is based on the plastic being burned in a pile with a forced-air current supplied to simulate
burning conditions in an air curtain. An air curtain is a portable or stationary combustion device
that directs a plane of forced air so as to create a curtain of air around the pit where the plastic is
burning. Air curtains are used in some states as a means of improving the combustion
characteristics of control burns involving agricultural plastic. The factors represent the average
of the emission rates for used and unused plastic. The test study on which both sets of emission
factors are based used plastic that consisted primarily of polyethylene and carbon black
(Linak etal., 1989).
4-465
-------
TABLE 4.10.3-1. PAH EMISSION FACTORS FOR OPEN BURNING OF AGRICULTURAL PLASTIC FILM
ON
sec
Number Emission Source Control Device Pollutant
5-03-002-02 Simulated Open None Benz(a)anthracene
Burning of Agricultural
Plastic Film (Pile Burn)
Benzo(a)pyrene
Benzo(b)fluoranthenc
Benzo(k)fluoranthene
Chrysene
Indeno( 1 ,2,3-cd)pyrc ne
Benzo(ghi)perylene
Anthracene
Fluoranthene
Phenanthrene
Pyrene
Retene
Average Emission
Factor in lb/1000 tons
(M8/kg)a
6.72E-02
(33.57)
4.93E-02
(24.65)
4.39E-02
(21.94)
1.63E-02
(8.13)
7.22E-02
(36.08)
5.08E-02
(25.37)
6.44E-02
(32.43)
8.45E-03
(4-23)
4.20E-01
(210.07)
8.45E-02
(42.23)
2.62E-01
(131.04)
5.12E-02
(25.58)
Emission Factor Range in
lb/1000 tons
(Mg/kg)a
2.88E-02- 1.06E-01
(14.41 -52.73)
1.51E-02-8.35E-02
(7.53-41.76)
1.85E-02-6.93E-02
(9.25 - 34.63)
5.00E-03 - 2.75E-02
(2.51 - 13.74)
3.44E-02-1.10E-01
(17.18-54.98)
2.14E-02-8.01E-02
(10.70 - 40.04)
2.99E-02 - 9.89E-02
(14.93 - 49.93)
2.60E-03- 1.43E-02
(1.32-7.14)
2.14E-01 -6.26E-01
(107.05-313.08)
4.81E-02- 1.21E-01
(24.05 - 60.40)
1.18E-01-4.07E-01
(58.81 -203.26)
3.75E-02 - 6.48E-02
(18.77-32.38)
Emission
Factor
Rating
C
C
C
C
C
C
C
C
C
C
C
C
(continued)
-------
TABLE 4.10.3-1. (Continued)
sec
Number Emission Source Control Device Pollutant
5-03-002-02 Simulated Open None Benzo(e)pyrene
(continued) Burning of Agricultural
Plastic Film (Pile Burn)
(continued)
5-03-002-02 Simulated Open None Benz(a)anthracene
Burning of Agricultural
Plastic Film (Forced
Air Burn)
Benzo(a)pyrene
Benzo(b)fluoranthenc
\
Benzo(k)fluoranthenc
Chrysene
Indeno( 1 ,2,3-cd)pyrene
Benzo(ghi)perylene
Anthracene
Fluoranthene
Phenanthrene
Average Emission
Factor in lb/1000 tons
(MS/kg)a
4.21E-02
(21.02)
4.10E-03
(2.05)
1.45E-03
(0.73)
2.55E-03
(1.26)
6.50E-04
(0.33)
4.90E-03
(2-45)
2.80E-03
(1.39)
2.10E-03
(1.06)
1.05E-03
(0.53)
9.25E-02
(46.26)
2.13E-02
(10.64)
Emission Factor Range in
lb/1000 tons
(Mg/kg)a
1.93E-02-6.48E-02
(9.65 - 32.38)
2.40E-03 - 5.80E-03
(1.19-2.91)
0.00 - 2.90E-03
(0.00- 1.45)
1.90E-03-3.20E-03
(0.93- 1.59)
0.00- 1.30E-03
(0.00 - 0.66)
2.40E-03 - 7.40E-03
(1.19-3.70)
0.00 - 5.60E-03
(0.00 - 2.78)
0.00 - 4.20E-03
(0.00-2.11)
8.00E-04-1.30E-03
(0.40 - 0.66)
7.82E-02- 1.07E-01
(39.12-53.39)
1.74E-02-2.51E-02
(8.72- 12.56)
Emission
Factor
Rating
C
C
C
C
C
C
C
C
C
C
C
(continued)
-------
TABLE 4.10.3-1. (Continued)
sec
Number
5-03-002-02
(continued)
Emission Source Control Device Pollutant
Simulated Open None Pyrene
Burning of Agricultural
Plastic Film (Forced
Air Burn) (continued)
Retene
Benzo(e)pyrene
Average Emission
Factor in lb/1 000 tons
(Mg/kg)a
2.57E-02
(12.10)
5.95E-03
(2.98)
1.45E-03
(0.73)
Emission Factor Range in
lb/1 000 tons
(ug/kg)a
1.19E-02-3.95E-02
(5.95- 18.24)
5.80E-03-6.10E-03
(2.91-3.04)
0.00 - 2.90E-03
(0.00- 1.45)
Emission
Factor
Rating
C
C
C
"Emission factors are expressed in Ib (ug) of pollutant emitted per 1,000 tons (kg) of plastic film burned.
Source: U.S. EPA, 1993.
*!
oo
-------
Source Location
The practice of burning agricultural plastic is likely to occur in rural areas, where
the material is regularly used by farmers to cover field crops. Permits may or may not be issued
for this type of open burning, and its occurrence could be affected by local regulations.
4-469
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SECTION 4.10.3 REFERENCES
Linak, W. B., J. V. Ryan, E. P., R. W. Williams, and David M. DeMarini. "Chemical and
Biological Characterization of Products of Incomplete Combustion from the Simulated Field
Burning of Agricultural Plastic." Journal of the Air and Waste Management Association.
Volume 39, No. 6, pp. 836-846. June 1989.
U.S. Environmental Protection Agency. Supplement F to Compilation of Air Pollutant Emission
Factors. Volume I: Stationary Point and Area Sources. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. AP-42, Volume I, Supplement F. July 1993.
pp. 2.4.14-2.4.19. 1993.
4-470
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4.10.4 Coal Refuse Burning
Process Description
Coal as it comes from a mine contains various amounts of impurities such as mine
waste, slate, shale, calcite, gypsum, clay, and pyrite. Together these wastes are referred to as coal
refuse or gob. The gob or refuse is separated from coal prior to its being marketed and is
commonly piled into banks or stored in impoundments near coal mines and coal preparation
plants. Coarse refuse (i.e., greater than 595 /urn diameter) is deposited into piles by dump trucks,
mine cars, conveyors, or aerial trams. Indiscriminate dumping and poor maintenance of refuse
piles are two practices that can result in spontaneous combustion of refuse piles (Chalekode and
Blackwood, 1978). Because they are sources of highly inefficient combustion, burning coal
refuse piles, outcrops, and mines have been identified as potential POM air emission sources
(Chalekode and Blackwood, 1978; Kelly, 1983).
Spontaneous ignition and combustion of coal refuse piles and impoundments is
mainly an oxidation phenomenon involving coal, associated pyrite, and impure coal substances.
The oxidation of carbonaceous and pyrite material in the coal refuse is an exothermic reaction.
The temperature of a coal refuse pile (or portions of it) increases if the amount of circulating air
is sufficient to cause oxidation, but insufficient to allow for dissipation of the resulting heat. The
temperature of the refuse pile then increases until ignition temperature is reached. Experimental
evidence has indicated that the heat of wetting of coal is greater than the heat of oxidation of
coal; therefore, the presence of moisture in air accelerates the self-heating process in coal refuse
piles. For this reason, the relative humidity of ambient air is a key factor affecting coal refuse
pile fires (Chalekode and Blackwood, 1978).
Coal textural moisture content (i.e., moisture retained in coal pores and void
spaces) is also an important variable in the occurrence of coal refuse fires. Upon exposure to air,
moisture is lost from the coal pores, leaving a significant area for oxygen adsorption. Increased
oxygen adsorption facilitates greater oxidation and promotes the development of coal refuse pile
fires (Chalekode and Blackwood, 1978).
4-471
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Oxidation of pyrite impurities in coal refuse piles is another supplementary factor
which enhances the possibility and severity of coal refuse combustion. Oxidation of pyrite is a
highly exothermic reaction that increases the temperature of surrounding material and thus
increases the rate of oxidation of the coal.
The spontaneous combustion of coal in outcrops and abandoned mines is also
attributable to oxidation phenomena involving coal, moisture, and pyrite impurities. Other
factors affecting combustion in mines and outcrops include coal rank, coal strata geology, and the
coal strata temperature profile. Low-rank coals such as subbituminous or high-volatile
bituminous are more susceptible to spontaneous combustion than a high-rank coal such as
low-volatile bituminous or anthracite. Low-rank coals contain a greater amount of moisture and
pyrite impurities than high-rank coals, which enhances their propensity for spontaneous
combustion. The presence of faults in coal seams enhances oxidation by providing channels for
greater volume and more distributed air flow. Coal strata temperature typically increases with
depth. Oxidation rate, therefore, will increase with depth, making the seam more vulnerable to
spontaneous combustion.
Various techniques exist to control emissions from burning coal refuse piles,
outcrops, and mines. The majority of these techniques are based on eliminating the oxygen
supply to extinguish the fire or on preventing the fire from spreading. The primary methods that
have been applied to refuse piles are described below:
Isolation - The burning area is isolated from the remainder of the
refuse pile by trenches and is quenched with water or blanketed
with incombustible material.
Blanketing - Some piles are extinguished by leveling the top, then
sealing the top and the sides with fine, incombustible material such
as flyash, clay, quarry wastes, or acid mine drainage sludge. Heavy
seals of such material are necessary to avoid erosion. The use of
clay is limited as it cracks over hot spots, impairing the seal. A
slurry of water and finely divided incombustible material, such as
pulverized limestone, flyash, coal silt, or sand, is forced into the
burning pile to provide some cooling action and also to fill the
voids to prevent air from entering the pile.
4-472
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Explosives - Many burning piles have an impenetrable,
ceramic-like, clinker surface which does not allow the penetration
of slurries and water. In this case, explosive charges are placed
deep into the bank through horizontally drilled holes. The
explosion creates fissures in the fused covering material. Water is
then applied through these crevices and the quenched material is
loaded out.
Spraying - In this method, water is sprayed over the entire refuse
bank. However, this is only a temporary solution as the pile
reignites with renewed vigor once the water spray is stopped.
Accelerated Combustion and Quenching - The burning refuse
material is lifted by a dragline and dropped through air into a
water-filled lagoon 49 to 98 feet (15 to 30 m) below for the
purpose of burning off the combustible material completely during
the drop. Another dragline and bulldozers are used to remove the
quenched material from the lagoon floor and compact it into a
tight, dense fill material.
Ponding - Retaining walls are constructed around the perimeter of
a refuse bank after subdividing the surface into a series of discrete
level areas and each area is filled with water to flood the fire. This
may cause explosions due to the formation of water gas. Water
penetration into the pile is poor.
Cooling and Dilution - Water is sprayed on the burning pile from
multiple nozzles and the cooled refuse is mixed, by bulldozer, in a
one-to-one volume proportion with soil and/or burned-out refuse
from a nearby area. The mixture is then compacted by heavy
equipment.
Hydraulic Jets - High velocity water cannons are used to quench
the burning refuse material. The quenched material is then
relayered and compacted by a dragline and bulldozer.
Emission Factors
PAH emission factors were found in the literature for coal refuse piles that are
burning (Chalekode and Blackwood, 1978). These factors are listed in Table 4.10.4-1. In the
referenced study, particulate POM emissions from a burning coal refuse pile were measured by
4-473
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TABLE 4.10.4-1. PAH EMISSION FACTORS FOR COAL REFUSE BURNING
SCC Number Emission Source Control Device Pollutant
A28- 10-000-000 Coal Refuse Burning None Benz(a)anthracene/Chrysene
Benzo(a)pyrene/
Benzo(e)pyrene/Perylene
Benzo(k or b)fluoranthene
Anthracene/Phenanthrene
Fluoranthene
Pyrene
Benzo(c)phenanthrene
Dibenzothiophene
Dimethylbenzanthracenes
(isomers)
Methylanthracenes,
-phenanthrenes
9-Methylanthracene
Average Emission
Factor in Ib/hr-ton
(kg/hr-metric ton)a
6.12E-09
(3.06E-09)
3.91E-10
(1.95E-10)
6.25E-10
(3.12E-10)
5.08E-09
(2.54E-09)
1.30E-09
(6.50E-10)
1.20E-09
(5.98E-10)
2.08E-10
(1.04E-10)
1.04E-10
(5.20E-11)
3.00E-09
(1.50E-09)
7.69E-09
(3.84E-09)
2.08-10
(1.04E-10)
Emission
Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
aEmission factors are in Ib (kg) of pollutant emitted per hr-ton (hr-metric ton) of burning refuse.
Source: Chalekode and Blackwood, 1978.
-------
using a high-volume filter air sampling device. The emission factors are based on test data from
a single bituminous coal refuse pile that had been smoldering for the last 10 years. There were
no control procedures identified for the sampled refuse pile.
As shown in Table 4.10.4-1, the following four compounds account for almost
84 percent of the measured POM emissions from the coal refuse pile: methylanthracenes/
phenanthrenes (30 percent), chrysene/benz(a)anthracene (24 percent), anthracene/phenanthrene
(20 percent), and dimethylbenzanthracenes [isomers] (12 percent). Other important PAHs, in
terms of carcinogenicity, were also detected, but in much lesser quantities.
Source Locations
Burning or potentially-burning coal refuse piles are linked to coal mining and coal
preparation plant locations. Recent information on the possible sources of burning refuse piles
was obtained from the U.S. Bureau of Mines (U.S. Bureau of Mines, 1994). A list of states and
Indian reservations where there are existing, unreclaimed gob piles and surface burning piles is
presented in Table 4.10.4-2. Gob piles are coal refuse piles that may or may not be burning, but
are generally of lower priority from a health standpoint because they not located in the vicinity of
a large human population. Surface burning piles are a higher priority coal refuse pile that is
actually burning and that is also in close proximity to a human population. The table lists the
number of sites and the total number of acres for these sites for each state and Indian reservation
in the country where data were available.
4-475
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TABLE 4.10.4-2. UNRECLAIMED COAL REFUSE SITES
AND ASSOCIATED ACREAGE
State/Tribe
Alaska
Alabama
Arkansas
Blackfeet
Colorado
Crow
Georgia
Hopi
Iowa
Illinois
Indiana
Jicarilla Apache
Kansas
Kentucky
Maryland
Michigan
Missouri
Montana
Navajo
North Dakota
New Mexico
Ohio
Oklahoma
Oregon
Pennsylvania
Rocky Boys
San Carlos Apache
Number of Goba
Sites
0
37
6
1
238
9
1
0
3
28
51
0
42
36
4
5
38
0
14
0
19
55
21
1
60
1
1
Gob Acres
0.0
415.5
53.0
0.5
500.3
11.0
4.0
0.0
3.0
308.7
495.3
0.0
203.0
446.5
11.0
19.0
118.8
0.0
48.0
0.0
110.0
753.0
229.5
5.0
1,207.0
1.0
0.2
Number of
Surface
Burning15 Sites
NDC
5
0
ND
1
ND
ND
ND
0
0
0
ND
0
20
1
0
0
0
0
0
1
3
ND
ND
19
ND
ND
Surface Burning
Acres
ND
32.5
0.0
ND
1.0
ND
ND
ND
0.0
0.0
0.0
ND
0.0
103.2
3.0
0.0
0.0
0.0
0.0
0.0
1.0
77.0
ND
ND
75.9
ND
ND
(continued)
4-476
-------
TABLE 4.10.4-2. (Continued)
State/Tribe
Southern Ute
Tennessee
Texas
Uintah and Ouray
Utah
Virginia
Washington
West Virginia
White Mountain Apache
Wind River
Wyoming
Total Nationwide
Number of Goba
Sites
5
35
0
1
12
131
10
241
1
12
1
1,120
Gob Acres
5.0
134.0
0.0
0.1
61.0
364.0
8.0
2,514.5
0.1
11.6
5.0
8,047.1
Number of
Surface
Burningb Sites
ND
1
ND
ND
6.0
5
0
26
ND
ND
0
82
Surface Burning
Acres
ND
1.0
ND
ND
0
19.9
0.0
112.3
ND
ND
0.0
432.8
aGob refers to the refuse or waste removed from an underground mine and includes mine waste, rock,
pyrites, slate, or other unmarketable materials which are separated during the cleaning process.
Gob sites have the potential to burn, but may not be presently burning.
bSurface burning refers to any sites where there is continuous combustion of mine waste material
resulting in smoke, haze, heat, or venting of hazardous gases within close distance to a populated
area and presenting a danger to public health, safety, and general welfare.
CND = no data reported.
Source: U.S. Bureau of the Mines, 1994.
4-477
-------
SECTION 4.10.4 REFERENCES
Chalekode, P.K., and T.R. Blackwood. Source Assessment: Coal Refuse Piles. Abandoned
Mines, and Outcrops - State of the Art. U.S. Environmental Protection Agency, Industrial
Environmental Research Laboratory, Cincinnati, Ohio. EPA Report No. 600/2-78-004v.
July 1978.
Kelly, M.E. Sources and Emissions of Polycyclic Organic Matter. U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina. EPA Report No. 450/5-83-010b.
pp. 5-3 to 5-9. 1983.
U.S. Bureau of the Mines. Abandoned Mine Land Inventory System. Branch of Technical
Support, Division of Abandoned Mine Land Reclamation. Washington, DC. 1994.
4-478
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4.10.5 Miscellaneous Open Burning
Process Description
The miscellaneous open burning category includes open burning activities not
covered in the discussions on coal refuse banks, wildfires and prescribed burning, scrap tire
burning, and agricultural plastic film burning. Types of open burning included in the
miscellaneous category are: municipal refuse open burning; open burning of scrap automobile
components (including the automobile body); open burning of waste railroad ties; and burning of
landscaping refuse (grass clippings, leaves, and branches). The purpose of burning in most of
these cases is volume reduction to facilitate final disposal of the waste material
(Siebert et al., 1978). In the case of automobile body burning, burning is performed to expedite
the recovery and recycling of usable metal in the automobiles by removing all organic materials
(plastic, vinyl, etc.) (Kelly, 1983).
The procedure of open burning in any of the miscellaneous categories is relatively
simple. The material to be burned (domestic trash, leaves, etc.) is collected and aggregated in an
open space fully exposed to the atmosphere. The materials are ignited and allowed to burn and
smolder until all combustible material is consumed or the desired degree of volume reduction is
achieved. Combustion efficiency in such operations is typically poor. Potential POM emissions
from such operations are highly variable because waste moisture content and combustion
conditions (air flow, oxygen levels, waste configuration, degree of exposed surface area) are
quite variable from site to site. In addition, some wastes may contain organic constituents that
are precursors to POM compounds or that accelerate POM compound formation.
Generally, there are two means to control POM emissions from miscellaneous
open burning—enclosure of the burning with exhaust ventilation to standard control devices and
prohibition of open burning. In most areas of the United States, open burning of municipal
refuse, automobiles, and grass, leaves, etc., has been greatly restricted, and in the case of
municipal refuse and automobile components, completely prohibited. Open burning of grass and
4-479
-------
leaves has been controlled by requiring collection agencies and the general public to have permits
for burning.
Emission Factors
The available emission factor data for open burning of municipal refuse
automobiles, and landscaping refuse are presented in Table 4.10.5-1 (Hangebrauck et al., 1967).
The data in Table 4.10.5-1 represent measured POM emission factors from tests conducted in a
laboratory research facility designed to simulate and characterize open burning emissions. The
laboratory experiments burned automobile components, municipal refuse, and landscaping refuse
(Hangebrauck et al., 1967). The results of the laboratory open burning tests are presented as a
function of the amount of waste burned. The factors could be determined for the laboratory open
burning tests because all conditions of the tests such as emission rates, flow rates, waste
throughput, etc., could be controlled. Conditions during actual open burning may not match the
exact conditions in the laboratory tests, so the user should use caution in applying these factors.
Source Location
The sources of miscellaneous open burning are extremely varied and their location
will depend on whether these activities are normally practiced in the local geographical area.
Obviously, where such activities are prohibited there is likely to be little activity besides that
associated with illegal burning. Burning of landscape refuse can take place at numerous
residential sites and it may be difficult to get data on the quantity of refuse burned. In most
cases, though, the user can assume a certain amount of waste generation per household or per
capita for many of the categories in order to calculate a preliminary estimate of emissions.
4-480
-------
TABLE 4.10.5-1. PAH EMISSION FACTORS FOR MISCELLANEOUS OPEN BURNING SOURCES
•p.
oo
SCC Number Emission Source Control Device Pollutant
5-03-002-02 Open Burning of None Benzo(a)pyrene
Municipal Refuse
Anthracene
Benzo(ghi)perylene
Fluoranthene
Phcnanthrene
Pyrene
Benzo(e)pyrene
Perylene
Anthanthrene
Coronene
5-03-002-01 Open Burning of None Benzo(a)pyrene
Landscaping Refuse
Anthracene
Benzo(ghi)perylene
Fluoranthene
*
Phenanthrene
Average Emission
Factor Ib/ton
(g/Mg)a
6.76E-04
(0.34)
ND
3.09E-04
(0.15)
3.23E-03
(1-61)
ND
3.54E-03
(1-76)
4.64E-04
(0.23)
ND
ND
ND
6.94E-04
(0.35)
ND
3.23E-04
(0.16)
2.23E-03
(1.11)
ND
Emission
Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.10.5-1. (Continued)
oo
N)
SCC Number Emission Source Control Device Pollutant
5-03-002-01 Open Burning of None Pyrene
(continued) Landscaping Refuse
(continued)
Benzo(e)pyrene
Perylene
Anthanthrene
Coronene
5-03-002-03 Open Burning of Scrap None Benzo(a)pyrene
Automobile Components
Anthracene
B enzo(ghi)pery lene
Fluoranthene
Phenanthrene
Pyrene
Benzo(e)pyrene
Average Emission
Factor Ib/ton
(g/Mg)a
3.45E-03
(1.72)
3.09E-04
(0.15)
7.51E-05
(0.04)
5.30E-05
(0.03)
ND
5.74E-02
(28.67)
6.27E-03
(3.13)
3.93E-02
(19.62)
1.08E-01
(53.80)
4.28E-02
(21.37)
1.52E-01
(75.63)
2.90E-02
(14.49)
Emission
Factor Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.10.5-1. (Continued)
-fc.
00
u>
SCC Number
5-03-002-03
(continued)
Emission Source Control Device Pollutant
Open Burning of Scrap None I'erylene
Automobile Components
(continued)
Anthanthrene
Coronene
Average Emission
Factor Ib/ton
(g/Mg)a
5.21E-03
(2.60)
4.42E-03
(2.21)
4.82E-03
(2.40)
Emission
Factor Rating
E
E
E
"Emission factors are expressed in Ib (g) of pollutant per ton (Mg) of refuse burned.
ND - Designates that compound was not detected.
Source: Hangebrauket al., 1967.
-------
SECTION 4.10.5 REFERENCES
Hangebrauck, R.P. et al. Sources of Polynuclear Hydrocarbons in the Atmosphere.
U.S. Department of Health, Education, and Welfare, Public Health Service, Cincinnati, Ohio.
Public Health Service Report No. AP-33. pp. 14-18. 1967.
Kelly, M.E. Sources and Emissions of Polycyclic Organic Matter. U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina. EPA Report No. 450/5-83-01 Ob.
pp. 5-93 to 5-95. 1983.
Siebert, P.C. et al. Preliminary Assessment of the Sources. Control, and Population Exposure to
Airborne Polycyclic Organic Matter (POND as Indicated by BenzoCalpyrene fBaP).
U.S. Environmental Protection Agency, Pollutant Strategies Branch, Office of Air Quality
Planning and Standards, Research Triangle Park, North Carolina. Prepared under EPA Contract
No. 68-02-2836. pp. 92-97. November 1978.
4-484
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4.11 MOBILE SOURCES
This section discusses mobile sources of POM emissions, which include on-road
vehicles, aircraft, locomotives, marine vessels, and non-road vehicles and equipment. Overall,
mobile sources are a significant contributor to POM emissions due to the large amount of activity
associated with onroad vehicles and the many non-road vehicle and equipment categories. The
primary sources of POM emissions from all the mobile sources are the incomplete combustion of
fuel in the internal combustion engines and the unburned fuel and lubricants used in the engines.
4.11.1 Onroad Vehicles
Source Description
The internal combustion engines of mobile sources emit gas-phase hydrocarbons
and particulate organic material as products of incomplete combustion and as noncombusted
(leaked) fuel, fuel additives, and lubricants. Some POM, such as the nitro derivatives, are
formed after the exhaust is released to the atmosphere. Nitro-PAH is formed when PAH in the
particulate reacts with NOX in the exhaust. The emission rate of POM from vehicle exhausts is
dependent on a large number of factors, including engine type, operating conditions, and
composition of both fuel and lubricating oil (Back et al., 1991).
After exhaust is released from a vehicle, it is diluted approximately 1,000-fold in
the first few seconds and cools very rapidly (National Research Council, 1983). POM and other
vapor-phase organic chemicals often condense on carbon nuclei and on other particles in the
exhaust that are also products of incomplete combustion. POM emissions from gasoline engine
vehicles with oxidation catalysts are generally sulfuric acid droplets less than 0.1 /^m in diameter
that have organic compounds adsorbed on their surfaces (National Research Council, 1983).
Particulate emissions from diesel engines are predominately elemental carbon particles that form
chains or clusters approximately 0.15 //m in diameter onto which the organic compounds are
adsorbed (National Research Council, 1983).
4-485
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POM compounds from vehicle engine exhaust are distributed between the vapor
phase and the particle phase, generally in accordance with their vapor pressures. POM
compounds containing two to four rings, such as naphthalene, are found primarily in the vapor or
gas phase, and the heavier POMs, such as benzo(a)pyrene, are found predominantly on particles
less than 1 /^m in diameter (Pederson et al., 1980). The actual distribution of POM between the
vapor phase and the particle phase will depend on the temperature and nature of the available
adsorption surface (Siegl and Chladek, 1992). Historically, particulate POM emissions from
mobile sources have generally been of the most interest; however, vapor-phase emissions are also
important from a health perspective because they have a higher chemical reactivity during
atmospheric transport. For example, the reaction of vapor-phase POM with hydroxyl radicals
and NO2 during atmospheric transport represents a major source of the nitro-substituted POM
found in ambient air (Siegl and Chladek, 1992).
Emissions of POM from gasoline automobiles and trucks are influenced by a
number of factors, such as air-to-fuel ratio; presence of emission controls; engine load; mode of
operation; extent of deterioration; and fuel effects. Fuel effects include aromaticity, POM
content, and the presence of additives or lubricants.
Changes in air-to-fuel ratios produce the largest effects on PAH emissions.
Air-to-fuel ratios less than stoichiometric promote incomplete combustion and, therefore,
increase emissions of CO and POM. It has been found that the amount of PAH in engine exhaust
generally decreases with an increasing air-to-fuel ratio (i.e., leaner mixture) (Pederson et al.,
1980). Leaner mixtures supply excess oxygen, resulting in more complete combustion and lower
emissions of PAH. For example, it has been estimated that 30 times more benzo(a)pyrene is
produced at a 10:1 air-to-fuel ratio than at a 14:1 ratio (National Research Council, 1972).
Noncatalyst automobiles have been shown to have higher emission rates than
automobiles equipped with catalytic converters. Rogge et al. reported a 25-fold higher total PAH
emission rate for autos without catalytic converters than for autos equipped with catalytic exhaust
emission control devices (1405.5 ug/km versus 52.5 ug/km) (Rogge et al., 1993).
4-486
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Westerholm et al. also reported dramatic decreases in POM emissions from vehicles equipped
with catalytic converters (Westerholm et al., 1992).
The effect of vehicle operation mode is related to the air-to-fuel ratio. Cold-start
operation will cause higher POM emissions because the engine is operating in a choked, or
fuel-rich, condition. Higher engine load also may increase POM emissions during cold starts.
Vehicle speed, a key variable in vehicle operation, is also suspected to affect POM emissions.
Westerholm et al. reported that an increase in PAH emissions was found with higher cruising
speeds (Westerholm et al., 1992).
The extent of deterioration, or mileage, of a vehicle has been shown to affect
POM emission rates significantly, with increasing deterioration over a threshold level causing
increased emission rates. Handa et al. estimated that average POM emission rates increase
linearly with mileage above 12,000 miles (Handa et al., 1984). Increased oil consumption is a
primary cause of the increased POM emissions with mileage. The higher quantity of oil in older,
more worn cylinders provides more intermediates for POM formation, and POM becomes
concentrated in the oil (National Research Council, 1983). Another cause of increased POM
emissions with mileage is the formation of deposits in the combustion chamber. Total
hydrocarbon emissions increase with mileage until the deposits become stabilized at several
thousand miles (National Research Council, 1983).
Fuel composition affects PAH emissions from vehicles. A number of studies
have shown that PAH emissions increase as the aromatic content of the fuel increases (Back,
1991). However, there is uncertainty as to whether the PAHs emitted in vehicle exhaust
represent those that survive the combustion process or those that were originally present in the
fuel. Westerholm et al. reported an increase in vapor-phase and particulate-phase PAH emissions
related to increases in fuel PAH input (Westerholm et al., 1988). Another study showed that
PAH emissions from a direct injection diesel engine increased as the aromatic content of the fuel
increased (Mills et al., 1984). Westerholm et al. also reported, however, that a large proportion
of fuel PAH input (>95 percent) is decomposed in the combustion process and that a major part
(>50 percent) of the emitted PAH is formed in the combustion process (Westerholm et al., 1988).
4-487
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Diesel-fueled vehicles emit paniculate emissions that primarily consist of
combustion-generated soot in combination with a solvent-extractable hydrocarbon fraction.
POM compounds are associated with the hydrocarbon fraction. Particulate POM emissions from
diesel vehicles are generally higher than those from catalyst-equipped gasoline vehicles. Rogge
et al. estimated that paniculate POM emission rates were four times higher from diesel trucks
than from catalyst-equipped gasoline vehicles (Rogge et al., 1993). The EPA has estimated that
light-duty diesel engines emit from 30 to 100 times more particles than comparable
catalyst-equipped gasoline vehicles (U.S. EPA, 1993).
Diesel paniculate matter is attributable to the incomplete combustion of fuel
hydrocarbons, the engine oil, and other unburned fuel components. The POM compounds
adsorbed or condensed onto the surface of carbon particles (i.e., soot particles) in the diesel
exhaust are sometimes referred to as the soluble organic fraction (SOF) of the particulate matter.
A significant part of the SOF is unburned lubricating oil that is vaporized from the cylinder walls
by the hot gases during the power stroke. The EPA estimates that 10 to 50 percent of the diesel
particulates formed are from engine oil (U.S. EPA, 1990). Some of the heavier hydrocarbons in
the fuel may come through unburned and condense on the soot particles. Mills et al.
demonstrated that PAH emissions from a direct injection diesel engine increased as the
aromaticity of the fuels was increased from 10 to 70 percent (Mills et al., 1984).
An existing control option for diesel engines that reduces diesel particulate
emissions is the combined technology of turbocharging and intercooling. Most heavy-duty diesel
engines have this technology, and it was required for virtually all engines in 1991. Catalytic
converters for diesel vehicles are also under development for more widespread use as a control
technology. These catalysts are very efficient in reducing emissions of particle-bound POM
compounds by oxidizing a large part of the SOF (U.S. EPA, 1990). Another control technology
being developed is trap oxidizers, which trap the diesel particulate matter and burn them after
they collect on a filter. Fuel reformulations are also being given serious consideration because
POM emissions can be reduced by reducing the aromatic hydrocarbon content of the fuel.
4-488
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Nitro-PAH compounds (a subset of POM) have also been found in diesel
paniculate emissions (National Research Council, 1983). One study (Lewtas, 1988) identified
23 different NO2-PAH in soot particle extracts from diesel engine exhaust. In the same study,
only one NO2-PAH (1-nitropyrene) was identified in gasoline engine exhaust samples. In
Lewtas' study, 1-nitropyrene is by far the most abundant nitro-PAH in diesel exhaust (107 to
1,590 ppm, relative to the weight of the extract), followed by the nitrophenanthrene/anthracene
isomers. Lang et al. (1981) also addressed the activity of POM in the exhaust by exposing POM
to filtered exhaust. They found that the paniculate can react with NOX in exhaust to form
nitro-PAH compounds.
Emission Factors
A large amount of the emissions testing data concerning POM emissions from
motor vehicles dates back to the 1970s and early 1980s, with many of the vehicles tested in those
studies spanning the model years of the late 1960s to the early 1970s. Many of the emission rates
estimated as part of those studies are now outdated because of the turnover of the vehicle fleet.
Since the time of those studies, leaded gasoline has been virtually phased out of use, the majority
of gasoline vehicles on the roads are now equipped with catalytic converters for emissions
control, emission standards have become stricter, and there have been major improvements in the
engine efficiency and performance of vehicles. All of these changes have generally helped to
reduce individual vehicle emissions, including POM emissions. These emissions reductions,
however, have been somewhat offset by the increase in vehicle miles travelled (VMT) occurring
in the United States. VMT increased approximately 40.6 percent between 1983 and 1990
(U.S. DOT, 1991).
The remainder of this section presents the latest available POM emission rate
information for gasoline and diesel vehicles. Because emission rates for motor vehicles vary
tremendously with operating conditions (e.g., speed, engine load, engine temperature), the results
from a number of different studies are presented. The user should select those emission rates that
best represent the conditions being modeled.
4-489
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Emission factors for PAH were developed as part of a significant tunnel sampling
program conducted at the Baltimore Harbor Tunnel in Maryland (Benner and Gordon, 1989).
Paniculate matter and gas-phase PAH samples were collected in exhaust rooms of the tunnel
during 1985 and 1986. Individual PAHs were identified and quantified by liquid and gas
chromatographic techniques. The study team developed PAH emission rates using a simple
model to convert observed PAH concentrations (ng/m3) in the tunnel exhaust room to emission
rates of PAH Gug/km). The resulting emission factors, which include particulate- and gas-phase
PAH, are shown in Table 4.11-1.
The emission factors shown in Table 4.11-1 represent "fleet-wide" emission
factors because they include all vehicle types traveling through the tunnel during the sample
period. The study concludes that tunnel samples are appropriate for estimating emission factors
because they represent actual samples from hundreds of vehicles, as opposed to PAH emission
factors that are based on combinations of single-vehicle data. The researchers estimated the
vehicle fleet breakdown as follows: 57.1 percent light-duty gasoline vehicles with a three-way
catalyst, 21.1 percent light-duty gasoline vehicles with no catalyst, and 6.3 percent light-duty
gasoline vehicles with an oxidation catalyst; 1.6 percent heavy-duty gasoline vehicles with no
catalyst; and 9.3 percent heavy-duty diesel vehicles and 4.5 light-duty diesel vehicles. The
emission rates in Table 4.11-1 can be used with fleet-wide VMT estimates to estimate emissions
for all vehicle types combined (Benner et al., 1989).
Particle-associated PAH compounds were measured for transient driving
conditions by Westerholm et al. (Westerholm et al., 1992). The study determined that the driving
conditions under which the vehicle engine is operated (i.e., speed and load) are important factors
in PAH exhaust emissions. The results of that study show that PAH emissions increase with
increased velocity and that they vary with changes in acceleration. It was also found that vehicles
equipped with a three-way catalyst had substantial reductions in PAH exhaust emissions over
noncatalyst vehicles.
4-490
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TABLE 4.11-1. FLEETWEDE PARTICULATE AND GAS-PHASE PAH EMISSION FACTORS FOR
ON-ROAD MOBILE SOURCES
4^
vo
SCC Number Emission Source Pollutant
22-0 1-000-000 and Gasoline and Diesel Benz(a)anthracene
22-30-000-000 On-Road Vehicles
Benzo(a)pyrene
Chrysene/Triphenylene
Indeno(l,2,3-cd)pyrene
Anthracene
B enzo(ghi)pery lene
Fluoranthene
Phenanthrene
Pyrene
Benzo(e)pyrene
Benzo(ghi)fluoranthene
Cyclopenta(cd)pyrene
Average Emission Factor
in Ib/mi (pg/km)a
6.00E-09
(2.00)
6.00E-09
(2.00)
9.00E-09
(3.00)
3.00E-09
(1.00)
1.80E-08
(6.00)
6.00E-09
(2.00)
2.40E-08
(8.00)
1.14E-07
(38.00)
2.40E-08
(8.00)
3.00E-09
(1.00)
6.00E-09
(2.00)
1.20E-08
(4.00)
Emission Factor Range in
Ib/mi (ug/km)a
1.50E-09-2.10E-08
(0.50 - 7.00)
9.00E-10-1.50E-08
(0.30 - 5.00)
3.00E-09 - 2.70E-08
(1.00-9.00)
1.20E-09- 1.20E-08
(0.40 - 4.00)
9.00E-09 - 3.00E-08
(3.00 - 10.00)
1.20E-09- 1.80E-08
(0.40 - 6.00)
1.20E-08-4.20E-08
(4.00 - 14.00)
6.60E-08-1.29E-07
(22.00 - 64.00)
1.20E-08-4.20E-08
(4.00 - 14.00)
9.00E-10- 1.20E-08
(0.30 - 4.00)
3.00E-09-1.50E-08
(1.00-5.00)
3.00E-09 - 2.70E-08
(1.00-9.00)
Emission Factor
Rating
C
C
C
C
C
C
C
C
C
C
C
C
(continued)
-------
TABLE 4.11-1. (Continued)
-P..
-k
VO
KJ
SCC Number Emission Source
22-0 1 -000-000 and Gasoline and Diesel
22-30-000-000 Onroad Vehicles
(continued) (continued)
Pollutant
3-Methylphenanthrene
1 -Methylphenanthrenes
2-Methylanthracene
Benzo(bj&k)fluoranthrene
Average Emission Factor
in Ib/mi (pg/km)a
4.20E-08
(14.00)
2.40E-08
(8.00)
6.00E-09
(2.00)
9.00E-09
(3.00)
Emission Factor Range in
Ib/mi (ng/km)a
2.70E-08 - 6.60E-08
(9.00 - 22.00)
1.50E-08-3.90E-08
(5.00- 13.00)
3.00E-09-1.20E-08
(1.00-4.00)
3.00E-09 - 3.00E-08
(1.00- 10.00)
Emission Factor
Rating
C
C
C
C
"Emission factors are expressed in Ib (ng) of pollutant emitted per mile (km) driven.
Source: Benneret a!., 1989.
-------
Emission factors for paniculate PAH for catalyst and noncatalyst gasoline-fueled
vehicles tested by Westerholm et al., are shown in Table 4.11-2. The results are shown for the
transient driving condition of acceleration from idle up to approximately 44 mph (70 kph)
followed by deceleration to idle again. The driving pattern follows that of the U.S. Federal Test
Procedure-75 (FTP-75) for warm engine operation. Factors are presented for noncatalyst
vehicles and for vehicles with a three-way catalyst installed, both running on unleaded gasoline
fuel (Westerholm et al., 1992).
In another study, Westerholm et al. estimated emission rates for gas-phase-
associated PAH (Westerholm et al., 1988). The study included sampling of gas-phase PAH
emissions from a 1984 Volvo 240 model vehicle with the catalyst removed. The results of the
study were integrated over all three phases (cold-start, hot-transient, and hot-start) of the U.S.
FTP-73 driving test pattern. The emission factors for gas-phase PAH for vehicles running on
fuel corresponding to commercially available unleaded gasoline are shown in Table 4.11-3. One
of the conclusions drawn by the authors of the study was that there is an increase in PAH
emissions due to fuel PAH input; however, a major portion of the fuel PAH input (greater than or
equal to 95 percent) is decomposed in the combustion process. They also concluded that a major
part of PAH emissions (greater than or equal to 50 percent) is formed in the combustion process.
Siegl and Chladek, also measured gas-phase PAH in gasoline vehicle exhaust
(Siegl and Chladek, 1992). The authors sampled emissions only for the hot-transient phase,
referred to as "Bag 3," of the U.S. FTP driving cycle. The vehicle tested was a 1987 model year
production vehicle equipped with a catalyst. Emission factors for nine PAH were measured in
both the pre-catalyst and post-catalyst exhaust. These emission factors are presented in
Table 4.11-4. All nine of the PAHs tested were detected in the pre-catalyst exhaust, but only six
were above the limit of quantitation. Seven of the nine PAH tested were detected in the
post-catalyst exhaust. The authors reported that the major differences between their results and
those from the Westerholm et al. (1988) study, primarily the much higher levels of naphthalene
and biphenyl, may be due to the differences in the testing methods used. The Westerholm study
used cryogenic trapping followed by a multi-step sample-handling procedure that may have
resulted in the loss of the relatively volatile PAH species (Siegl and Chladek, 1992).
4-493
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TABLE 4.11-2. PARTICULATE PAH EMISSION FACTORS FOR LIGHT-DUTY GASOLINE VEHICLES
DURING THE WARM-ENGINE OPERATION FTP DRIVING CYCLE
SCC Number Emission Source Pollutant
22-01-001-000 Light-Duty Gasoline Benz(a)anthracene
Vehicles
Benzo(a)pyrene
Benzo(b,k)fluoranthene
Chrysene/Triphenylene
Indeno(l ,2,3-cd)pyrene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Phenanthrene
Pyrene
Benz(a)fluorene
Benzo(e)pyrene
Benzo(ghi)fluoranthene
Noncatalyst Emission Factor
in Ib/mi
(Mg/km)a
2.97E-09
(0.991)
9.00E-10
(0.300)
3.27E-09
(1.089)
2.52E-09
(0.840)
8.34E-10
(0.278)
1.35E-10
(0.045)
1.65E-09
(0.550)
1.98E-09
(0.660)
4.77E-10
(0.159)
2.70E-09
(0.900)
2.34E-10
(0.078)
2.40E-09
(0.800)
3.30E-09
(1.100)
Catalyst Emission
Factor in Ib/mi
(Mg/km)a
2.01E-10
(0.067)
3.06E-10
(0.102)
4.62E-10
(0.154)
3.00E-10
(0.100)
2.82E-10
(0.094)
6.00E-12
(0.002)
2.97E-10
(0.099)
2.49E-10
(0.083)
6.00E-11
(0.020)
6.00E-11
(0.020)
6.00E-12
(0.002)
4.20E-10
(0.140)
1.26E-10
(0.042)
Emission
Factor Rating
D
D
D
D
D
D
D
D
D
D
D
D
D
(continued)
-------
TABLE 4.11 -2. (Continued)
Noncatalyst Emission Factor
in Ib/mi
SCC Number Emission Source Pollutant (ng/km)a
22-01-001-000 Light-Duty Gasoline Coronene
(continued) Vehicles (continued)
Cyclopenta(cd)pyrene
2-Methylanthracene
Perylene
1-Methylphenanthrene
3-Methylphenanthrene
4 and 9-Methylphenanthrene
1-Methylpyrene
2-Methylpyrene
Indeno( 1 ,2,3-cd)fluoranthene
1-Nitropyrene
8.67E-10
(0.289)
9.00E-10
(0.300)
3.51E-10
(0.117)
1.14E-10
(0.038)
2.10E-10
(0.070)
2.61E-10
(0.087)
9.30E-11
(0.031)
2.46E-10
(0.082)
5.28E-10
(0.176)
6.90E-11
(0.023)
9.90E-10
(0.330)
Catalyst Emission
Factor in Ib/mi
(Mg/km)a
1.68E-10
(0.056)
2.40E-11
(0.008)
6.00E-12
(0.002)
3.00E-12
(0.001)
6.00E-12
(0.002)
6.00E-12
(0.002)
3.00E-12
(0.001)
3.00E-12
(0.001)
6.00E-12
(0.002)
1.20E-11
(0.004)
4.20E-10
(0.140)
Emission
Factor Rating
D
D
D
D
D
D
D
D
D
D
D
"Emission factors are expressed in Ib (ng) of pollutant emitted per mile (km) driven.
Source: Westerholm et a!., 1992.
-------
TABLE 4.11-3. GAS-PHASE EMISSION FACTORS FOR NONCATALYST LIGHT-DUTY GASOLINE VEHICLES
fe
SCC Number Emission Source Pollutant
22-01-001-000 Light-Duty Gasoline Vehicles Benz(a)anthracene
Chrysene/Tri phenylene
Acenaphthylene
Fluorene
Naphthalene
Anthracene
Fluoranthene
Phenanthrenc
Pyrene
Benzo(ghi)fluoranthene
Biphenylene
Methylpyrenc
Hmission Factor
in Ib/mi
(Mg/km)a
3.30E-09
(1.10)
1.53E-09
(0.51)
8.40E-08
(28.00)
1.26E-07
(42.00)
6.90E-08
(23.00)
8.40E-08
(28.00)
5.40E-08
(18.00)
2.73E-07
(91.00)
5.10E-08
(17.00)
2.07E-09
(0.69)
2.49E-08
(8.30)
9.60E-10
(0.32)
Emission
Factor Rating
D
D
D
D
D
D
D
D
D
D
D
D
-------
TABLE 4.11-3. (Continued)
SCC Number Emission Source
22-01-001-000 Light-Duty Gasoline Vehicles
(continued) (continued)
Pollutant
1 -Methy Iphenanthrenes
1 -Methylanthracene
Emission Factor
in Ib/mi
(Mg/km)a
4.80E-08
(16.00)
ND
Emission
Factor Rating
D
D
"Emission factors are expressed in Ib (jag) of pollutant emitted per mile (km) driven.
ND = not detected.
Source: Westerholmet al., 1988.
-------
TABLE 4.11-4. GAS-PHASE PAH EMISSION FACTORS FOR LIGHT-DUTY GASOLINE VEHICLES
DURING THE HOT-START TRANSIENT PHASE OF THE FTP DRIVING CYCLE
VO
oo
SCC Number Emission Source Pollutant
22-01-001-000 Light-Duty Gasoline Anthracene
Vehicles
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
Biphenyl
1 -Methylnaphthalene
2-Methylnaphthalene
Noncatalyst Emission
Factor in Ib/mi (|jg/km)a
2.98E-09
(9.94E-01)
4.10E-09
(1.37E+00)
1.08E-08
(3.60)
3.75E-06
(1249.01)
4.10E-09
(1.37E+00)
3.73E-09
(1.24)
1.16E-07
(38.53)
7.27E-07
(242.35)
1.57E-06
(521.98)
Catalyst-Equipped
Emission Factor in Ib/mi
(ug/km)a
ND
(ND)
4.10E-09
(1.37)
ND
(ND)
5.20E-07
(173.37)
4.10E-09
(1.37)
4.10E-09
(1.37)
1.04E-08
(3.48)
3.11E-08
(10.38)
6.47E-08
(21.56)
Emission
Factor
Rating
D
D
D
D
D
D
D
D
D
"Emission factors are expressed in Ib (pg) of pollutant emitted per mile (km) driven.
ND = Not detected.
Source: Siegletal., 1992.
-------
SECTION 4.11.1 REFERENCES
Back, S.O., R.A. Field, M.E. Goldstone, P.W. Kirk, and J.N. Lester. "A Review of Atmospheric
Polycyclic Aromatic Hydrocarbons: Sources, Fate and Behavior." Water, Air, and Soil
Pollution, Volume 60, pp. 279-300. 1991.
Benner, B. A., and G. E. Gordon. "Mobile Sources of Atmospheric Polycyclic Aromatic
Hydrocarbons: A Roadway Tunnel Study." Environmental Sciences and Technology, Volume
23, No. 23, pp. 1269-1278. 1989.
Handa, T., T. Yamauchi, K. Sawai, T. Yamamura, Y. Koseki, and T. Ishii. "In Situ Emission
Levels of Carcinogenic and Mutagenic Compounds from Diesel and Gasoline Engine Vehicles
on an Expressway." Environmental Science and Technology. 18(12), pp. 895-902. 1984.
Lang, J.M., L. Snow, R. Carlson, F. Black, R. Zweidinger, and S. Tejada. "Characterization of
Particulate Emissions from In-Use Gasoline-Fueled Motor Vehicles." Society of Automotive
Engineers, Warrendale, Pennsylvania. SAE Paper 811186. 1981.
Lewtas, J. "Experimental Evidence for the Carcinogenicity of Air Pollutants."
U.S. Environmental Protection Agency, Health Effects Research Laboratory, Research Triangle
Park, North Carolina, pp. 54-55. 1990.
Lewtas, J. "Genotoxicity of Complex Mixtures: Strategies for the Identification and
Comparative Assessment of Airborne Mutagens and Carcinogens from Combustion Sources."
Fundamental and Applied Toxicology, Volume 10, pp. 571-589. 1988.
Mills, G.A., J.S. Howarth, and G.A. Howard. Journal of Inst. Energy, p. 273. 1984.
National Research Council. Polycyclic Aromatic Hydrocarbons: Evaluation of Sources and
Effects. Committee on Pyrene and Selected Analogues, Board on Toxicology and Environmental
Health Hazards, Commission on Life Sciences, National Academy Press, Washington, DC.
pp. 1-1 to 1-35. 1983.
National Research Council. Particulate Polycyclic Organic Matter. Committee on Biologic
Effects of Atmospheric Pollutants. Division of Medical Sciences, National Academy of
Sciences, Washington, DC. pp. 15-21. 1972.
Pederson, P.S., J. Ingwersen, T. Nielsen, and E. Larsen. "Effects of Fuel, Lubricant, and Engine
Operating Parameters on the Emission of Polycyclic Aromatic Hydrocarbons." Environmental
Science and Technology. 14(l):71-79. 1980.
Rogge, W. F., L. M. Hildemann, M. A. Mazurek, and G. R. Cass. "Sources of Fine Organic
Aerosol 2. Noncatalyst and Catalyst-Equipped Automobiles and Heavy-Duty Diesel Trucks."
Environmental Sciences and Technology, Volume 27, No. 4, pp. 636-651. 1993.
4-499
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Siegl, W. O., and E. Chladek. "Measurement of Gas-Phase Polycyclic Aromatic Hydrocarbons
(PAH) in Gasoline Vehicle Exhaust." Presented at the Symposium on Mechanisms and
Chemistry of Pollutant Formation and Control from Internal Combustion Engines, American
Chemical Society, Washington, DC. pp. 1499-1504. August 23-28, 1992,
U.S. Department of Transportation. Highway Statistics 1990. Federal Highway Administration,
Washington, DC. FHWA-PL-91-003. p. 209. 1991.
U.S. Environmental Protection Agency. Motor Vehicle-Related Air Toxics Study. Office of
Mobile Sources, Ann Arbor, Michigan. EPA-420-R-93-005. p. ES-29. 1993-..
U.S. Environmental Protection Agency. Emissions Control Strategies for Heavy-duty Diesel
Engines. Office of Mobile Source Air Pollution Control, Ann Arbor, Michigan.
EPA-460/3-90-001. p. 41. 1990.
Westerholm, R. N., J. Almen, and H. Li. "Exhaust Emissions from Gasoline-FueMed Light Duty
Vehicles Operated in Different Driving Conditions: A Chemical and Biological
Characterization." Atmospheric Environment, Volume 26B, No. 1, pp. 79-90. 1992.
Westerholm, R. N., T. E. Alsberg, A. B. Frommelin, and M. Strandell. "Effect of Fuel
Polycyclic Aromatic Hydrocarbon Content on the Emissions of Polycyclic Aromatic
Hydrocarbons and Other Mutagenic Substances from a Gasoline-Fueled Automobile."
Environmental Sciences and Technology, Volume 22, No. 8, pp. 925-930. 1988.
4-500
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4.11.2 Aircraft
Process Description
There are two main type of aircraft engines in use today: the turbojet and piston.
A kerosene-like fuel is used in the jet engines, while gasoline is used for piston engines. The fuel
combustion process in aircraft engines results in exhaust emissions to the atmosphere. Studies of
aircraft exhaust have reported the presence of PAH compounds (Spicer et al., 1987; AESO,
1990).
The aircraft fleet in the United States totals about 198,000, including both civilian
and military aircraft. In terms of number of aircraft, most of the fleet is made up of general
aviation aircraft operated by single- and twin- piston engines. However, most of the fuel
consumption and the associated emissions are from commercial jet transports and military
aircraft (U.S. EPA, 1993). Most commercial jet transports have two, three, or four engines,
while military aircraft range from single or dual engine fighters to multi-engine transports with
either turbojet or turboprop engines.
The fuel combustion in jet engines is a continuous process that supplies heated,
expanded gases which are forced through a turbine to drive an associated propeller (turboprop),
or are expelled through the aft end of the engine to provide direct thrust (turbojet). Factors
affecting emissions from these engines include engine type, fuel type, power setting, and fuel
flow rate. These parameters can vary widely from aircraft to aircraft, especially between those
used for civilian operations and those dedicated to military use.
PAH formation in a turbine engine occurs in the primary and secondary
combustion zones. In the primary combustion zone, incompletely combusted fuel droplets with
diameters of 50 to 200 /^m lead to the formation of paniculate matter which consists primarily of
carbon particles. Oxidation in the secondary combustion zone leads to particles of about 0.01 to
0.1 i^m. At the exit of the combustion chamber in the engine, agglomerated particles about 0.6 to
0.8 ^urn remain in the turbine exhaust. PAH compounds are bound to these particles.
4-501
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Fuel type is an important parameter that affects the characteristics and quantity of
emissions from aircraft. For example, JP-5 is a less volatile fuel than JP-4, and would be
expected to have different emission characteristics. Changes in fuel composition may, therefore,
affect PAH emissions from these sources. Testing performed by the U.S. Air Force has been
done primarily with JP-4, but civil aircraft use Jet-A fuel, which is a less volatile fuel that tends
to produce less smoke (U.S. EPA, 1993). It is possible that the smoke reduction may also equate
to a reduction in toxics, including PAH, that are normally absorbed or condensed on the smoke
particles.
Emission Factors
Few studies have developed emission factors specific to aircraft engine exhaust.
Available information reports concentrations of various pollutants detected in the engine exhaust.
Most of the emissions testing has been conducted by military organizations, and applicability to
civil aircraft may not be direct due to the differences in type of fuel used. Existing data suggests
that fuel composition is the major determinant of engine exhaust emissions.
The EPA summarized PAH concentrations in the exhaust gas from emissions
testing conducted on two engine types: a CFM-56 engine using JP-5 fuel (representing
commercial applications of a recent technology, fuel efficient, advanced emission abatement
design) and an F-l 10 military aircraft engine using JP-4 fuel (U.S. EPA, 1997).
Table 4.11.2-1 presents the individual fractions of PAH relative to VOC which can be used with
VOC emissions estimates to calculate individual PAH emissions. The PAH/VOC fractions were
developed from concentration measurements for individual PAH species and VOC as reported in
the EPA summary (U.S. EPA, 1997). The PAH/VOC fractions are provided for four modes of
operation (idle, 30 percent power, 63 percent power, and intermediate) for the F-l 10 military
aircraft engine. The intermediate mode relates to 100 percent of rated thrust. There are three
modes of operation (idle, 30 percent power, and 80 percent power) covered by the CF-56 engine
data. Depending on a specific airport facilities operations, the time spent by the aircraft in any
one of these particular modes can vary.
4-502
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TABLE 4.11.2-1. PAH EMISSION CONCENTRATIONS IN AIRCRAFT GAS TURBINE ENGINE EXHAUST
Control
SCC Number Emission Source Device Pollutant
22-75-001-000 Gas Turbine Engine in None Anthracene
F-l 10 Military Aircraft
Using JP-4 Fuel Benzo(a)anthracene
Benzo(a)pyrene .
Benzo(g,h,i)perylene
Chrysene
Fluoranthene
Naphthalene (g)
Phenanthrene
Pyrene
22-75-001-000 Gas Turbine Engine in Emission Anthracene
CFM-56 Aircraft Using Abatement
JP-5 Fuel Design Benzo(a)anthracene
Benzo(a)pyrene
Benzo(g,h,i,)perylene
Chrysene
Fluoranthene
Naphthalene (g)
Phenanthrene
Pyrene
Idle
3.09E-06
7.24E-07
1.27E-06
7.58E-07
1.29E-06
1.16E-05
1.18E-04
3.35E-05
1.39E-05
4.00E-07
5.28E-08
2.81E-08
4.67 E-09
5.61E-08
8.25 E-07
4.31E-04
3.64 E-06
1.01 E-06
PAH/VOC Concentration Fi actions"
30% 63% 80%
power power power
3.12E-06
9.30E-07
9.46E-07
4.77E-07
2.91 E-06
2.36E-05
1.88E-04
4.64E-05
2.36E-05
1.09E-06
4.03E-06
2.55E-06
3.56E-07
4.29E-07
8.24E-06
7.98E-05
3.54E-05
6.76E-06
6.57E-06
2.18E-06
2.54E-06
2.01 E-06
3.68E-06
2.61E-05
1.83E-04
1.07E-04
2.61E-05
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
1 .46E-06
1 .04E-06
7.47E-07
1 .68E-07
2.02E-07
4.55E-06
4.74E-05
3.08E-05
3.64E-06
Emission
Factor
Intermediate Ratingc Reference
6.54E-06 NA U.S. EPA, 1997
2.24E-06
2.37E-06
2.72E-06
3.25E-06
2.69E-05
1.71E-04
8.78E-05
2.13E-05
NA NA U.S. EPA, 1997
NA
NA
NA
NA
NA
NA
NA
NA
"Concentration ratios expressed as parts per million as carbon (ppbC) of PAH divided by ppbC VOC.
NA = not applicable; ratings are not applicable since relative concentrations, not emission factors, are presented.
Source: U.S. EPA, 1997.
-------
Simplified emission factors for PAH were derived as part of the MOE Toxic and
Chemical Emission Inventory for Ontario and North America (Johnson et al., 1990) and are
shown in Table 4.11.2-2. The emission factors presented in that study were derived from 1979
data on PAH concentrations in the exhaust paniculate from a small gas turbine engine burning
conventional fuel. Emission factors were then derived in units of mass of pollutant per landing
and takeoff cycle (LTO). An LTO consists of the following operating modes:
• Approach;
• Taxi/idle in;
• Taxi/idle out;
Takeoff; and
• Climb out.
LTO data are available from annual Federal Aviation Authority (FAA) publications (e.g., Federal
Air Traffic Activity and Airport Activity Statistics of Certified Route Air Carriers'), and are the
common form of activity level used for many inventory applications. The LTO cycle represents
the emissions occurring in the air quality zone of interest (i.e., the LTO cycle typically occurs
between ground level and the local inversion height).
Additional information on PAH emissions from aircraft have been reported.
Kuhlman and Chuang, concluded that most PAH in the engine exhaust decrease in concentration
as engine operating power increases. Exceptions to this were fluoranthene and pyrene, which
persisted at a 30 percent engine power setting (Kuhlman and Chuang, 1989a). Naphthalene was
by far the PAH with the highest concentration measured in the exhaust gas from the three jet
turbine engines tested in that study. Concentrations for naphthalene ranged from 17.7 Atg/m3 to
2560 Mg/m3 (Kuhlman and Chuang, 1989b).
4-504
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TABLE 4.11.2-2. PAH PARTICULATE EMISSION FACTORS FOR AIRCRAFT GAS TURBINE ENGINES
Ui
o
Ui
SCC Number Emission Source Control Device Pollutant
22-75-020-000 Aircraft Gas Turbine Engine None Benz(a)anthracene
Benzo(a)pyrene
Chrysene
Anthracene
Benzo(ghi)perylene
Fluoranthene
Phenanthrene
Pyrene
Benzo(e)pyrene
Average Emission
Factor in Ib/LTO
(mg/LTO)a
1.44E-06
(0.65)
2.74E-06
(1.24)
6.81E-06
(3.08)
8.00E-06
(3.62)
3.58E-06
(1.62)
8.20E-05
(37.10)
1.06E-04
(47.80)
9.55E-05
(43.20)
7.96E-07
(0.36)
Emission
Factor
Rating6
U
U
U
U
U
U
U
U
U
"Emission factors are expressed in Ib (mg) of pollutant emitted per landing and take-off cycle (LTD).
'These factors are assigned a "U5" rating since the original test data on which they are based, and the derivation of the factors, was not reviewed.
Source: Johnson et al., 1990.
-------
SECTION 4.11.2 REFERENCES
Aircraft Environmental Support Office (AESO). Toxic Organic Contaminants in the Exhaust of
Gas Turbine Engines. Aircraft Environmental Support Office, Naval Aviation Depot, North
Island, San Diego, California. AESO Report No. 12-90. September 1990.
Johnson, N.D., M.T. Schultz, V. Cassaday, and K. Davidson. MOE Toxic Chemical Emission
Inventory for Ontario and Eastern North America. Prepared for the Air Resources Branch,
Ontario Ministry of the Environment, Rexdale, Ontario. Draft Report No. P.89-50-5429/OG.
pp. 211-213. March 1990.
Kuhlman, M.R., and J.C. Chuang. Characterization of Chemicals on Engine Exhaust Particles.
Battele Columbus Division, Columbus, Ohio. ESL-TR-88-50. p. 77. June 1989a.
Kuhlman, M.R., and J.C. Chuang. Characterization of Chemicals on Engine Exhaust Particles.
Battele Columbus Division, Columbus, Ohio. ESL-TR-88-50. p. 40. June 1989b.
Spicer, C.W., M.W. Holdren, S.E. Miller, D.L. Smith, R.N. Smith, M.R. Kuhlman, and D.P.
Hughes. Aircraft Emissions Characterization: TF41-A2. TF-30-P103. and TF30-P109 Engines.
Tyndall Air Force Base, Florida. ESL-TR-87-27. December 1987.
U.S. Environmental Protection Agency. Memorandum from Rich Cook, Assessment and
Modeling Division to Joe Touma, Office of Air Quality Planning and Standards, Subject:
"PAH/VOC Emission Fractions for Aircraft." National Vehicle and Fuel Emissions Laboratory,
Ann Arbor, Michigan. March 18, 1997.
U.S. Environmental Protection Agency. Toxic Emissions from Aircraft Engines: A Search of
Available Literature. Office of Air Quality Planning and Standards, Research Triangle Park,
North Carolina. EPA-453/R-93-028. July 1993.
4-506
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4.11.3 Locomotives. Marine Vessels, and Other Non-road Vehicles and Equipment
Process Description
There are a variety of non-road vehicles and equipment types that can produce
POM emissions from the fuel combustion in the engines that power them. Included among these
are locomotives, marine vessels, and other non-road vehicles and equipment. The locomotives of
concern for POM emissions are those that are powered by internal combustion diesel-fueled
engines (as opposed to electric-powered locomotives, which receive their energy from a
stationary point source utility plant). Marine vessels that have either diesel-fueled internal
combustion engines or residual oil-fueled boilers are of concern regarding POM emissions.
Included in "other non-road vehicle and equipment" are: lawn and garden equipment,
recreational vessels, industrial equipment, construction equipment, agricultural equipment, and
logging equipment. The other non-road vehicles and equipment have 2-stroke gasoline, 4-stroke
gasoline, or diesel-powered internal combustion engines that can produce POM emissions.
Most non-road engines used on locomotives, marine vessels, and other non-road
vehicles and equipment are not currently regulated for emissions. There are very few non-road
engines with emission control devices. Like onroad mobile sources, all of these non-road
engines produce diesel exhaust and gasoline exhaust particulate matter, a portion of which
consists of POM.
Emission Factors
There has been no information collected on the emission rates of specific POM
compounds found in the exhaust of non-road engines and vehicles. Particulate matter from
non-road mobile sources is estimated to contribute a median of 1.8 percent of the total PM
emission inventory in a typical nonattainment area (U.S. EPA, 1993). The two major equipment
categories contributing are construction equipment and commercial marine equipment. The
available PM emission factors for non-road vehicles and equipment are outdated. In some cases
(such as where they based on the use of leaded gasoline), would be incorrect to use in deriving
4-507
-------
emission factors. These categories of non-road engines should be identified as potential sources
of POM in any inventory study. Some of these sources are scheduled to be regulated in the
future, which may produce emission testing data that can be used in deriving POM emission
factor data.
4-508
-------
SECTION 4.11.3 REFERENCES
U.S. Environmental Protection Agency. Motor Vehicle-Related Air Toxics Study. Office of
Mobile Sources, Ann Arbor, Michigan. EPA 420-R-93-005. pp. 14-1 to 14-2. 1993.
4-509
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4.12 MISCELLANEOUS SOURCES
4.12.1 Carbon Black Manufacture
Process Description
Carbon black is a major industrial chemical used primarily as a reinforcing agent
in rubber compounds, especially tires (Serth and Hughes, 1980). The chemical carbon black
consists of finely divided carbon produced by the thermal decomposition of hydrocarbons. The
manufacture of carbon black is of potential concern for POM emissions because the predominant
production process involves the combustion of natural gas and the high-temperature pyrolysis of
aromatic liquid hydrocarbons.
Approximately 90 percent of all carbon black produced in the United States is
manufactured by the oil-furnace process shown in Figure 4.12.1-1 (Serth and Hughes, 1980;
Serth and Hughes, 1977). The process streams identified in Figure 4.12.1-1 are defined in
Table 4.12.1-1. All oil-furnace carbon black plants are similar in overall structure and operation.
The most pronounced differences in plants are primarily associated with the details of the
decomposition furnace design and raw product processing (Serth and Hughes, 1980). Other
processes used for carbon black production are thermal decomposition of natural gas and
exothermic decomposition of acetylene (Serth and Hughes, 1977).
In the oil-furnace process, carbon black is produced by the pyrolysis of an
atomized liquid hydrocarbon feedstock in a refractory-lined steel furnace. Processing
temperatures in the steel furnace range from 2,408 to 2,804°F (1,320 to 1,540°C). The heat
needed to accomplish the desired hydrocarbon decomposition reaction is supplied by the
combustion of natural gas (Serth and Hughes, 1980).
4-510
-------
ATMOSPHERIC EMISSIONS
OH. STORAGE TANK
VENT GAS
MAIN PROCESS VENT GAS
———-.—*•. INCINERATOR STACK GAS
FUGITIVE EMISSIONS
^PNEUMATIC SYSTEM
VENT GAS
*». DRYER VENT GAS
VACUUM CLEAN UP
SYSTEM VENT OAS
TO STORAGE OPTIONAL STREAM
Figure 4.12.1-1. Process Flowsheet for an Oil-Furnace Carbon Black Plant
Source: Serth and Hughes, 1977.
-------
TABLE 4.12.1-1. STREAM CODE FOR THE OIL-FURNACE PROCESS
ILLUSTRATED IN FIGURE 4.12.1-1
Stream Identification
1 Oil feed
2 Natural gas feed
3 Air to reactor
4 Quench water
5 Reactor effluent
6 Gas to oil preheater
7 Water to quench tower
8 Quench tower effluent
9 Bag filter effluent
10 Vent gas purge for dryer fuel
11 Main process vent gas
12 Vent gas to incinerator
13 Incinerator stack gas
14 Recovered carbon black
15 Carbon black to micropulverizer
16 Pneumatic conveyor system
17 Cyclone vent gas recycle
18 Cyclone vent gas
19 Pneumatic system vent gas
20 Carbon black from bag filter
21 Carbon black from cyclone
22 Surge bin vent
23 Carbon black to pelletizer
24 Water to pelletizer
25 Pelletizer effluent
26 Dryer direct heat source vent
27 Dryer bag filter vent
28 Carbon black from dryer bag filter
29 Dryer indirect heat source vent
30 Hot gases to dryer
4-512 (continued)
-------
TABLE 4.12.1-1. (Continued)
Stream
Identification
31
32
33
34
35
36
37
38
39
Dried carbon black
Screened carbon black
Carbon black recycle
Storage bin vent gas
Bagging system vent gas
Vacuum cleanup system vent gas
Dryer vent gas
Fugitive emissions
Oil storage tank vent gas
Source: Serth and Hughes, 1980.
4-513
-------
Feed materials used in the oil-furnace process consist of petroleum oil, natural
gas, and air. Also, small quantities of alkali metal salts may be added to the oil feed to control
the degree of structure of the carbon black (Serth and Hughes, October 1977). The ideal raw
material for the production of modern, high-structure carbon black is an oil that is highly
aromatic; low in sulfur, asphaltenes and high molecular weight resins; and substantially free of
suspended ash, carbon, and water. The reactor for the oil furnace process consists of a
refractory-lined steel furnace 4.9 to 29.5 feet (1.5 to 9 m) in length with an internal diameter of
0.49 to 2.5 feet (0.15 to 0.76 m).
To provide maximum efficiency, the furnace and burner are designed to separate,
insofar as possible, the heat-generating reaction from the carbon-forming reaction. Thus, the
natural gas feed (Stream 2 in Figure 4.12.1-1) is burned to completion with preheated air
(Stream 3) to produce a temperature of 2,408 to 2,804°F (1,320 to 1,540°C). The reactor is
designed so that this zone of complete combustion attains a swirling motion, and the oil feed
(Stream 1), preheated to 392 to 698°F (200 to 370°C), is sprayed into the center of the zone. Oil
preheating is accomplished by heat exchange with the reactor effluent and/or by means of a
gas-fired heater. The oil is cracked to carbon and hydrogen, with side reactions producing carbon
oxides, water, methane, acetylene, and other hydrocarbon products. The heat transfer from the
hot combustion gases to the atomized oil is enhanced by highly turbulent flow in the reactor
(Serth and Hughes, 1977).
The reactor converts 35 to 65 percent of the feedstock carbon content to carbon
black, depending on the feed composition and the grade of black being produced. The yields are
lower for the smaller particle size grades of black. Variables that can be adjusted to produce a
given grade of black include operating temperature, fuel concentration, space velocity in the
reaction zone, and reactor geometry (which influences the degree of turbulence in the reactor).
The hot combustion gases and suspended carbon black are cooled to about
1,004°F (540°C) by a direct water spray in the quench area, which is located near the reactor
outlet. The reactor effluent (Stream 5 in Figure 4.12.1-1) is further cooled by heat exchange in
4-514
-------
the air and oil preheaters. It is then sent to a quench towers where direct water sprays finally
reduce the stream temperature to 446°F (230°C).
Carbon black is recovered from the reactor effluent stream by means of a bag
filter unit. The exhaust gas from the bag filter unit (Stream 9 in Figure 4.12.1-1) is vented
directly to the atmosphere in most carbon black plants. Alternatively, it may be sent to a flare or
incinerator to reduce contaminant loading (Stream 12). In addition, 13 to 15 percent of the
effluent (Stream 10) may be diverted to produce auxiliary fuel for the raw product drying
operation.
The raw carbon black collected in the bag filter unit must be further processed to
become a marketable product. After passing through the pulverizer, the black has a bulk density
of 24 to 59 kg/m3, and it is too fluffy and dusty to be transported. It is therefore converted into
pellets or beads with a bulk density of 97 to 171 kg/m3. In this form, it is dust-free and
sufficiently compacted for shipment.
Rotating horizontal drums operating at 374 to 392 °F (190 to 230°C) are typically
used for product drying in carbon black processes. The dryers are fueled by natural gas, which
may be augmented by a portion of the main process vent gas. From 35 to 70 percent of the
combustion gas is charged directly to the interior of the dryer. After passing through the dryer,
this stream (Stream 26) is sent to a bag filter for removal of entrained carbon black before being
vented to the atmosphere. The remaining 30 to 65 percent of the combustion gas (Stream 29)
acts as an indirect heat source for the dryer and is vented directly to the atmosphere.
The dried, pelletized carbon black (Stream 31) is screened and sent to a covered
storage bin via a bucket elevator. Oversize pellets are removed in the screener and recycled
(Stream 33) to the pulverizer. From the product storage bin, the carbon black can be loaded into
railroad hopper cars for bulk shipment or sent to a vacuum bagging system that is hermetically
sealed to prevent emission of carbon black (Serth and Hughes, 1977).
4-515
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Exhaust gas from the bag filter unit constitutes the main process vent and the
largest source of POM emissions. About two-thirds of U.S. carbon black plants treat the bag
filter exhaust stream to control CO and hydrocarbon emissions. Combustion in thermal
incinerators, flares, or CO boilers is used for treating the gases. In the remaining facilities, bag
filter exhaust emissions are vented directly to the atmosphere (Kelly, 1983). Emissions from
product dryers are predominantly controlled by high-efficiency bag filter units; however, water
scrubbers are also used at a few facilities (Serth and Hughes, 1977).
POM emissions associated with raw carbon black production (exclusive of
additional processing steps) appear to be a function of the efficiency of the product recovery bag
filter and, where applicable, the destructive or potentially constructive effect of hydrocarbon and
CO combustion control devices. Because decreased efficiency in the product recovery bag filter
unit means decreased carbon black production and lost revenues, it is likely that companies
maintain these bag filters maintained at optimum conditions. The use of combustion control
devices would be expected to reduce POM emissions by them into constituent compounds and
elements (water, CO2, nitrogen). Some investigators have speculated that POM compounds are
being formed in the high temperature zone of the hydrocarbon and CO control devices but did
not supply data to support this POM formation theory (Serth and Hughes, 1980).
Emission Factors
Several emission factors for POM emissions from carbon black manufacturing
were identified in the literature. All identified emission factors are applicable to emissions from
the main process vent. No emissions data of any type were available for potential POM sources
associated with raw product processing such as grinding, drying, and packaging.
A well-documented source of uncontrolled main process vent PAH emission
factors from carbon black manufacturing are those developed by Serth and Hughes (1980).
Uncontrolled POM emissions from the main process vent (product recovery baghouse) were
measured in a series of three tests, with the average emission factor for total POM being
0.0039 Ib/ton (0.002 kg/Mg) of carbon black produced. Of the total 1,900 mg POM, 42 percent
4-516
-------
was acenaphthylene, 26 percent was pyrene, and 12 percent was methyl- and
dimethylanthracenes/phenanthrenes. Mean PAH emission factors are presented in
Table 4.12.1-2.
All POM sampling in the Serth and Hughes work was conducted using EPA
Modified Method 5. Both vapor phase and paniculate POM were quantified.
Johnson, et al. (1990) presented emission factors for individual PAH species from the entire
oil-furnace carbon black production process (Table 4.12.1-3). Emission factors were derived for
material handling operations and furnace process fugitives using measured carbon black PAH
concentrations and an EPA particulate emission factor of 1.06 Ib/ton (0.53 kg/Mg)
(Nishioka et al., 1986). The resulting emission factors were summed with the main process vent
emission factors cited in Serth and Hughes, (1980) to represent the entire carbon black
production process. Included in the aggregate emission factors are the transport air vent, pellet
drying, bagging and loading operations, furnace process fugitives, and main process vent
emissions. Emission factors were calculated assuming all fugitive PM emitted from the carbon
black production process was in the form of carbon black (Johnson et al., 1990).
Source Locations
As of January 1993, there were 24 known carbon black manufacturing facilities in
the United States. Over 75 percent of all carbon black production occurs in the states of Texas
and Louisiana (36 and 40 percent, respectively). The location of all facilities and their estimated
annual production capacities in 1985 are provided in Table 4.12.1-4 (SRI, 1993).
4-517
-------
TABLE 4.12.1-2. PAH EMISSION FACTORS FOR OIL FURNACE CARBON
BLACK MANUFACTURING: MAIN PROCESS VENT
oo
Control
SCC Number Emission Source Device Pollutant
3-01-005-04 Main Process Vent None Ben/(a)anthracene/Chrysene
Ben/.opyrenes and perylene
Ben/.ofluoranthenes
Dibcnzanthracenes
Indeno(l ,2,3-cd)pyrene
Acenaphthylene
Anlhracene/Phenanthrene
Ben/.o(ghi)perylene/Anthanthrene
Fluoranthene
Dimethylanthracenes/Phenanthrenes
Pyrene
Ben/,o(c)phenanthrene
Average Emission
Factor in Ib/ton
(kg/Mg)a
1.80E-05
(9.00E-06)
6.00E-05
(3.00E-05)
6.00E-05
(3.00E-05)
<4.00E-06
(<2.00E-06)
<4.00E-06
(<2.00E-06)
1.60E-03
(8.00E-04)
1.40E-04
(7.00E-05)
4.60E-05
(2.30E-05)
1.20E-04
(6.00E-05)
2.80E-04
(1.40E-04)
l.OOE-03
(5.00E-04)
<4.00E-06
(<2.00E-06)
Emission
Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.12.1-2. (Continued)
Control
SCC Number Emission Source Device Pollutant
3-01-005-04 Main Process Vent None Benzo(ghi)fluoranthene
(continued) (continued)
Dihenzo(c,g)carbazole
Dibenzopyrenes
Dibenzothiophene
7, 1 2-Dimethyl(a)anthracene
Methylanthracenes/Phenanthrenes
Melhylcholanthracene
Melhylfluoranthenc/Pyrene
Average Emission
Factor in Ib/ton
(kg/Mg)a
8.00E-05
(4.00E-05)
<4.00E-06
(<2.00E-06)
<4.00E-06
(<2.00E-06)
2.80E-05
(1.40E-05)
1.40E-04
(7.00E-05)
2.00E-04
(l.OOE-04)
<4.00E-06
(<2.00E-06)
4.60E-05
(2.30E-05)
Emission
Factor
Rating
E
E
E
E
E
E
E
E
aEmission factors are in Ib (kg) of pollutant emitted per ton (Mg) of carbon black produced.
Source: Serth and Hughs, 1980.
-------
TABLE 4.12.1-3. PAH EMISSION FACTORS FOR OIL FURNACE CARBON
BLACK MANUFACTURING: TOTAL PROCESS
Ul
Control
SCC Number Emission Source Device Pollutant
3-01-005-04, -06, Total Process None Benz(a)anthracene
-07, -08, -09
Benzo(a)pyrene
Benzofluoranthenes
Chrysene
Acenaphthylene
Fluoranthene
Phenanthrene
Pyrene
Benzo(e)pyrene
Cyclopenta(cd)pyrene
Dibenzothiophene
Methylanthracenes/Methylphenanthrenes
Average Emission
Factor in Ib/ton
(kg/Mg)a
1.66E-05
(8.30E-06)
2.86E-04
(1.43E-04)
1.88E-04
(9.40E-05)
3.40E-05
(1.70E-05)
1.60E-03
(8.00E-04)
1.06E-03
(5.30E-04)
2.56E-04
(1.28E-04)
1.60E-03
(8.00E-04)
2.20E-04
(1.10E-04)
7.40E-05
(3.70E-05)
8.20E-05
(4.10E-05)
2.00E-04
(l.OOE-04)
Emission
Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
4^
to
TABLE 4.12.1-3. (Continued)
Control
SCC Number Emission Source Device Pollutant
3-01-005-04, -06, Total Process None Perylene
-07, -08, -09
Triphenylene
Average Emission
Factor in Ib/ton
(kg/Mg)a
1.42E-04
(7.10E-05)
l.OOE-06
(5.00E-07)
Emission
Factor
Rating
E
E
"Emission factors are in Ib (kg) of pollutant emitted per ton (Mg) of carbon black produced.
Source: Johnson et al., 1990.
-------
TABLE 4.12.1-4. LOCATION AND ANNUAL CAPACITIES OF
CARBON BLACK PRODUCERS IN 1993
Company
Cabot Corporation
Chevron Corporation
Columbian Chemicals Company
Degussa Corporation
Ebonex Corporation
General Carbon Company
Hoover Color Corporation
J.M. Huber Corporation
Sid Richardson Carbon and Gasoline
Company
Witco Corporation
TOTAL
Facility Location
Franklin, LA
Pampa, TX
Villa Platte, LA
Waverly, WV
Cedar Bayou, TX
El Dorado, AR
Moundsville, WV
North Bend, LA
Ulysses, KS
Arkansas Pass, TX
Belpre, OH
New Iberia, LA
Melvindale, MI
Los Angeles, CA
Hiwassee, VA
Baytown, TX
Borger, TX
Orange, TX
Addis, LA
Big Springs, TX
Borger, TX
Phoenix City, AL
Ponca City, OK
Sunray, TX
Annual Capacity,
MM Ib (MM kg)
260(118)
60 (27)
280 (127)
180(82)
20(9)
110(50)
180(82)
240 (109)
80 (36)
130 (59)
140 (64)
240(109)
8(4)
1 (0.5)
1 (0.5)
225 (102)
175 (79)
135(61)
145 (66)
115(52)
275 (125)
60 (27)
255(116)
120 (54)
3,435 (1,558)
NOTE: This list is subject to change as market conditions change, facility ownership changes, plants are
closed down, etc. The reader should verify the existence of specific facilities by consulting current
lists and/or the plants themselves. The level of POM emissions from any given facility are a
function of variables such as capacity, throughput, and control measures, and should be determined
through direct contacts with plant personnel.
Source: SRI, 1993.
4-522
-------
SECTION 4.12.1 REFERENCES
Johnson, N.D., M.T. Schultz, V. Cassaday, and K. Davidson. MOE Toxic Chemical Emission
Inventory for Ontario and Eastern North America. Prepared for the Air Resources Branch,
Ontario Ministry of the Environment, Rexdale, Ontario. Draft Report No. P.89-50-5429/OG.
p. 93. 1990.
Kelly, M.E. Sources and Emissions of Polycyclic Organic Matter. U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina. EPA Report No. 450/5-83-01 Ob.
pp. 5-85 to 5-88. 1983.
Nishioka, M., H. Chang, and M.L. Lee. "Structural Characteristics of Polycyclic Aromatic
Hydrocarbon Isomers in Coal Tars and Combustion Products." Environ. Sci. Technol. 20(10).
pp. 1023 -1027. 1986.
Serth, R.W., and T.W. Hughes. "Polycyclic Organic Matter (POM) and Trace Element Contents
of Carbon Black Vent Gas." Environmental Science and Technology. 14(3):298-301. March
1980.
Serth, R.W., and T.W. Hughes. "Source Assessment: Carbon Black Manufacture."
U.S. Environmental Protection Agency, Industrial Environmental Research Laboratory, Research
Triangle Park, North Carolina. EPA Report No. 600/2-77-107k. October 1977.
SRI International. 1993 SRI Directory of Chemical Producers - United States of America.
Menlo Park, California, p. 509. 1993.
4-523
-------
4.12.2 Wood Treatment/Wood Preserving
Process Description
Creosote impregnation plants, also called wood treatment plants, have been
identified as potential air emission sources of POM because creosote contains significant
quantities of POM compounds. Creosote is a product of the fractional distillation of coal tar,
which is a byproduct of bituminous coal coking. The principal use of creosote is as a wood
preservative. It is used to treat crossties, switch ties, utility poles, crossarms, marine and
foundation pilings, construction lumber, and fence posts (Wallingford and Que Hee, 1985).
Other wood treatment/preservation processes using pentachlorophenol and chromated copper
arsenate have not been identified as sources of POM emissions.
Creosote wood treatment is accomplished by either pressure or non-pressure
processes. To initiate either process, wood products are debarked, sawed, and conditioned.
Conditioning primarily involves the removal of moisture from the wood to enhance the
penetration and retention of the preservative. Moisture reduction conditioning may be
accomplished by outdoor storage (air seasoning) or by artificial conditioning processes. To
expedite certain treatment processes, the wood may be pierced by knives (a process called
incising) to provide avenues for penetration of the preservative solutions (U.S. Department of
Agriculture, 1980).
The three primary methods of conditioning used in the wood treatment industry
are steaming-and-vacuum, boiling-under-vacuum (the Boulton process), and vapor drying
(Vaught and Nicholson, 1989).
The steaming-and-vacuum conditioning process involves the steaming of wood in
the treatment cylinder (retort) for several hours at approximately 245°F (118°C). Following
steaming, a vacuum is applied to the cylinder, causing moisture removal by mechanical and
evaporative mechanisms.
4-524
-------
A generic flow diagram of a wood preserving facility using the Boulton
conditioning process is presented in Figure 4.12.2-1. In the Boulton (boiling-under-vacuum)
process, the treatment cylinder containing timbers is filled with hot preservative oil. The cylinder
is kept heated while a vacuum is applied. The heat causes a lowering of the boiling point of the
water in the wood, resulting in evaporation. Evaporated moisture from the wood and vapors
from the hot preservative oil are passed through a condenser to recover preservative via oil/water
separation. The Boulton process has several advantages over other conditioning processes,
including lower temperature requirements, minimal impact on wood strength and physical
condition, and a grearer moisture reduction capacity than the steaming process (Vaught and
Nicholson, 1989).
The vapor-drying process uses a boiling organic solvent such as xylene to
vaporize moisture from the wood during condensation. As the organic vapors condense, latent
heat is given up, causing vaporization of water. Water and solvent vapors are passed through a
condenser to recover solvent.
Ninety-five percent of all treated wood is preserved through pressurized
processes. These processes involve the application of pneumatic or hydrostatic pressure to
expedite the movement of preservative liquid into the wood. In the normal application of
preservatives (e.g., creosote), wood is first loaded onto trams and introduced into the pressure
vessel. In the pressure vessel, wood can be creosote pressure-treated by either the full-cell or the
empty-cell process (U.S. Department of Agriculture, 1980).
In the full-cell process, an initial vacuum is applied to the charge for a period of
about 30 minutes. At the end of this period, and while still maintaining the vacuum, the vessel is
filled with creosote. The vacuum is then released and pressures of 50 to 250 psi are applied to
the system. Pressure is maintained until the required gross absorption of preservative has been
achieved. At the end of the pressure cycle, the pressure is reduced to atmospheric levels and the
preservative liquid in the vessel is returned to storage. The treated wood will often be subjected
to a final vacuum to remove excess preservative on the surface of the wood. Upon completion,
the vacuum is released, the door of the vessel is opened, and the treated stock is removed.
4-525
-------
FUGITIVE AIR EMISSIONS
DURING UNLOADING AND CHARGING
WOOD IN
WOOD OUT
VAPORS
TREATING
CYLINDER
COOLING
WATER
COOLING
WATER
PRESERVATIVES
TO WORK TANK
WORK
TANK
AIR AND
VAPORS
CYLINDER DRIPPINGS
AND RAIN WATER
PRESERVATIVES
TO CYLINDER
RECOVERED
OILS
(
OIL-WATER
SEPARATOR
WASTEWATER.
EVAPORATION
TOWER
RECYCLE TO
WORK TANK
CONDENSATE
AIR EMISSIONS
SLUDGE
Figure 4.12.2-1. Flow Diagram of a Wood Preserving Facility Using the Boulton Conditioning Process
Source: U.S. EPA, 1988.
-------
Creosote retentions achieved by the full-cell process vary from 20 to 30 lb/ft3 (320 to 480 kg/m3)
(U.S. Department of Agriculture, 1980).
The objective of the empty-cell process is to obtain deep preservative penetration
with relatively low total retention. In the process, the treatment retort is filled with preservative
while either at ambient pressure conditions or under an initial air pressure of 25 to 100 psi,
depending on the net retention of preservative desired and the resistance of the wood. After
preservative has been added to the cylinder, the treatment pressure is elevated and maintained for
a period of time. The expansive force of compressed air acts to drive out some of the
preservative absorbed during the treatment process (Vaught and Nicholson, 1989). The
remainder of the treating process is the same as that described for the full-cell process.
Depending on the specifications of the customer, wood preservative retentions achieved by the
empty-cell process range from 6 to 12 lb/ft3 (96 to 208 kg/m3) (U.S. Department of Agriculture,
1980).
In both the full-cell and empty-cell processes, creosote may be applied in an
undiluted form or it may be diluted with coal tar or petroleum. Treatment using mixtures of
creosote and heavy oils (i.e., No. 6 Oil) is referred to as the diluent process (Ebasco, 1989).
Application temperatures for creosote and its solutions range from 210 to 230°F (99 to 110°C).
Products such as marine pilings are always treated by the full-cell process. Utility
poles, crossties, and fence posts are routinely treated by the empty-cell process. The amount of
preservative retention needed and the treatment process required are determined by the biological
hazard to which the treated wood will be subjected in service. Creosote is also used as a
restricted use pesticide (Ware, 1996).
Non-pressurized wood treatment processes are used commercially. Creosote use
by individual consumers is restricted to those who are licensed applicators (Ware, 1996).
4-527
-------
Generally, wood treated by non-pressure processes must be seasoned to a moisture content of
30 percent or less prior to treatment to provide the best results (U.S. Department of Agriculture,
1980).
Most commercial non-pressure creosote treatments are applied by cold-soak or
thermal processes. In both processes, wood is exposed to the preservative in an open vessel. The
principle behind the cold-soak process simply entails soaking seasoned wood in the preservative
for a fixed period of time or until a predetermined gross retention has been achieved. The
thermal process involves exposing wood to hot creosote for 6 to 12 hours followed by exposure
to the preservative at ambient temperature for 2 hours (U.S. Department of Agriculture, 1980).
The creosote wood treatment source category is a source of primarily fugitive
POM emissions that are associated with the actual treatment process and, to a greater degree, the
handling of creosote raw materials and treated products. Fugitive emissions from treatment
occur when the treatment vessel is opened at the end of the cycle. The duration of such
emissions from each vessel is relatively short because vessels are only opened once or twice
during each working shift (Wallingford and Que Hee, 1985; Andersson et al., 1983).
Fugitive POM emissions may occur during creosote transfer from an incoming
tanker or rail car to plant storage facilities. The method and frequency of delivery is a function of
plant size and location. Generally, the larger the facility, the more numerous and voluminous the
creosote deliveries will be. Increased frequency and quantity means increased potential for
emissions. Transfer of the preservative, whether from rail car or tanker, is normally
accomplished using a closed piping system. In such a system, the greatest chance for fugitive
emissions is at the origin, where creosote is leaving the tanker or rail car, and at the end of the
transfer, where creosote is entering the storage vessel (Wallingford and Que Hee, 1985;
Andersson et al., 1983).
The storage of creosote-impregnated lumber products at a treatment facility has
been identified as the most significant POM emission source of the entire operation. The
evaporative fugitive emissions from product storage are dependent on both the treatment process
4-528
-------
(primarily the preservative solution constituency) and the flux through the storage cycle. As
would be expected, fresh product POM emissions are greater than aged product emissions
(Koppers Ind., 1990). If treated products are stored in a building, emissions of this type would be
largely confined and atmospheric emissions significantly reduced (Wallingford et al., 1985;
Andersson et al., 1983).
According to EPA, only a small percentage of creosote wood treatment facilities
have air pollution control systems. Most facilities use vapor condensers for product recovery
from treatment cylinders. These condensers also serve to significantly reduce the vaporous POM
concentrations in cylinder fugitive and vacuum pump gases. Seven or eight U.S. facilities are
currently using wet scrubbers to control emissions from treatment vessels and vacuum pumps.
One facility is operating a fume incinerator, which was tested for total hydrocarbon by EPA in
1993. Hydrocarbon emissions were non-detectable at the fume incinerator outlet. Biological
treatment technologies are currently being marketed to the wood treatment industry for both
water treatment and post-scrubber air polishing (Grumpier Telecon, 1994).
Emission Factors
Emission factors for three processes in the creosote wood treatment source
category were derived from two test reports conducted at a single facility. The emission factors
represent the following processes/process groupings: (1) the creosote treatment process with
associated chemical handling and treatment process fugitives; (2) the diluent treatment process
with associated chemical handling and treatment process fugitives; and (3) the treated wood
product storage piles.
PAH emission factors for the creosote wood treatment process and associated
process fugitives are presented in Table 4.12.2-1. The emission factors represent emissions from
the creosote working tank vent, the treatment cylinder vacuum exhaust, the cylinder fill vent, the
cylinder sump, rail tank car unloading, the oil water separator, and cylinder piping. The reported
emissions data used in emission factor development were based on a combination of point source
stack sampling, emission factors based on liquid sampling, and mass balance calculations.
4-529
-------
TABLE 4.12.2-1. PAH EMISSION FACTORS FOR CREOSOTE WOOD TREATMENT
SCC Number Emission Source3 Control Device Pollutant
3-07-005-01 Treatment Cylinder and Vapor Condenser Acenaphthylene
Process Fugitives
Fluorene
Naphthalene
Phenanthrene
2-Methylnaphthalene
Average Emission
Factor in lb/ft3
(kg/m3)b
6.13E-04
(9.83E-03)
1.67E-04
(2.67E-03)
2.20E-03
(3.52E-02)
1.14E-04
(I.83E-03)
2.58E-03
(4.14E-02)
Emission
Factor
Ratingc
U
U
U
U
U
^ "Point sources: Creosote working tank vent, cylinder vacuum exhaust, and cylinder fill vent;
^ Fugitive sources: Rail tank car unloading, cylinder sump, cylinder unloading, oil/water separator, and cylinder piping.
— — T"!
Emission factors are in Ib (kg) of pollutant emitted per ft (m ) of treated wood produced and are based on stack sampling data, liquid sampling
data/emission factors, and material balance.
'Factor was assigned a U rating because factors were developed from mass balance dala that did not have sufficient supporting documentation to determine a
valid rating.
Source: Ebasco, 1989; Koppers Ind., 1990.
-------
PAH emission factors for the diluent wood treatment process and associated
process fugitives are presented in Table 4.12.2-2. The diluent process involved wood treatment
using creosote mixed with No. 6 fuel oil. The emission factors represent emissions from the
diluent working tank vent, the treatment cylinder vacuum exhaust, the cylinder fill vent, the
cylinder sump, rail tank car unloading, the oil water separator, and cylinder piping. The reported
emissions data used in emission factor development were based on a combination of point source
stack sampling, emission factors based on liquid sampling, and mass balance calculations.
Fugitive emissions from both treatment process ancillary operations (i.e., other
than direct treatment process emissions) were germane to both the creosote and diluent
processes. This category of general fugitive emissions included such processes as wastewater
treatment, cylinder sumps, chemical unloading, and piping fugitive emissions from piping
common to both treatment operations.
Specific PAH emissions data for both the creosote and diluent treatment process
were available for the five most prevalent species emitted. Additional categories identified in the
reported test data were titled "additional PAHs detected" and "PAHs below detection limits in
gas stream." However, the magnitude of these grouped emissions for both processes was
significantly lower than the lowest-emitting PAH species reported.
PAH emission factors for creosote-treated wood product storage piles are
presented in Table 4.12.2-3. Testing was conducted at a wood treatment facility under enclosed
conditions with induced air flow. Treated timbers of various ages, from 1 to 30 days
post-treatment, were tested to determine an average emission factor per unit stored with an
assumed flux of material to and from the storage yard. The total magnitude of PAH emissions
from product storage has been reported at approximately 1.6 percent of the total amount of PAH
compounds found in the process chemical used per year. This compares to 2.0 percent emitted
from all treatment and storage operations combined (Ebasco, 1989).
4-531
-------
TABLE 4.12.2-2. PAH EMISSION FACTORS FOR DILUENT WOOD TREATMENT
SCC Number Emission Source3 Control Device Pollutant
3-07-005-01 Treatment Cylinder and Vapor Condenser Acenaphthene
Process Fugitives
Fluorene
Naphthalene
Phenanthrene
2-Methylnaphthalene
Average Emission
Factor in lb/ft3
(kg/m3)b
8.08E-05
(1.29E-03)
3.72E-05
(5.96E-04)
6.28E-04
(1.01E-02)
4.11E-05
(6.58E-04)
4.91E-04
(7.86E-03)
Emission
Factor
Rating0
U
U
U
U
U
aPoint sources: Creosote working tank vent, cylinder vacuum exhaust, and cylinder fill vent;
Fugitive sources: Rail tank car unloading, cylinder sump, cylinder unloading, oil/water separator, and cylinder piping.
''Emission factors are in Ib (kg) of pollutant emitted per ft3 (m3) of treated wood produced and are based on stack sampling data, liquid sampling
data/emission factors, and material balance.
cFactor was assigned a U rating because factors were developed from mass balance data that did not have sufficient supporting documentation to determine a
valid rating.
Source: Ebasco, 1989; Koppers Ind., 1990.
-------
TABLE 4.12.2-3. PAH EMISSION FACTORS FOR CREOSOTE/DILUENT TREATED WOOD STORAGE
SCC Number Emission Source Control Device Pollutant
3-07-005-01 Treated Wood Storage None Ben7o(a)pyrene
Pile
Ben/o(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Dibe nz(a,h)anthracene
Indeno( 1 ,2,3-cd)pyrene
Acenaphthene
Acenaphthylene
Anthracene
Ben/.o(ghi)perylene
Fluoranthene
Fluorene
Average Emission
Factor in lb/ft3
(kg/m3)a
1.23E-08
(1.96E-07)
1.35E-06
(2.16E-05)
1.12E-06
(1.79E-05)
4.78E-08
(7.66E-07)
1.69E-12
(2.70E-11)
5.90E-12
(9.46E-I1)
0.0117
(0.187)
4.18E-04
(6.69E-03)
4.03E-04
(6.46E-03)
5.22E-12
(8.36E-11)
4.13E-04
(6.61E-03)
6.66E-03
(1.07E-01)
Emission Factor
Rating
E
E
E
E
E
E
E
E
E
E
E
E
(continued)
-------
TABLE 4.12.2-3. (Continued)
Average Emission
Factor in Ib/ft3
SCC Number Emission Source Control Device Pollutant (kg/m3)3
3-07-005-01 Treated Wood Storage None Naphthalene 0.0222
(continued) Pile (continued) (0.355)
Phcnanthrene 8.58E-03
(0.137)
Pyrene 7.80E-05
(1.25E-03)
Emission Factor
Rating
E
E
E
"Emission factors are in Ib (kg) of pollutant emitted per ft3 (m3) of treated wood stored and are based on pilot stack sampling data.
Source: Koppers Ind., 1990.
-------
Source Locations
Creosote wood treatment plants are located across the country, but they are
predominantly found in the Southeast. Information compiled by the American Wood Preservers
Association and the American Wood Preservers Institute indicates that there are roughly
83 creosote pressure treatment plants nationwide (Micklewright, 1990). A list identifying these
facilities is given in Table 4.12.2-4.
4-535
-------
TABLE 4.12.2-4. LIST OF CREOSOTE WOOD PRESSURE TREATMENT
PLANTS IN THE UNITED STATES IN 1989
Company
Location
Brown Wood Preserving Company, Inc.
Cahuba Pressure Treated Forest Products
Huxford Pole and Timber Company, Inc.
I. R. Miller Mill Company, Inc.
Koppers Company, Inc.
Seaman Timber Company
Stallworth Timber Company
Arizona Pacific Wood Preserving, Inc.
Koppers Company, Inc.
Thompson Industries, Inc.
J. H. Baxter and Company
Koppers Company, Inc.
McCormick & Baxter Creosoting Company
Pacific Wood Preserving of Bakersfield
San Diego Wood Preserving
Koppers Company, Inc.
Perma Treat Corporation
Koppers Company, Inc.
Atlantic Wood Industries, Inc.
B & M Wood Products, Inc.
Baxley Creosoting Company, Inc.
Brunswick Wood Preserving Company, Inc.
Glennville Wood Preserving Company
Manor Timber Company, Inc.
Union Timber Corporation
Kerr-McGee Chemical Corporation
Koppers Company, Inc.
Koppers Company, Inc.
Northport, AL
Brierfield, AL
Huxford, AL
Brewton, AL
Montgomery, AL
Montevallo, AL
Beatrice, AL
Elroy, AZ
North Little Rock, AR
Russellville, AR
Weed, CA
Oroville, CA
Stockton, CA
Bakersfield, CA
National City, CA
Denver, CO
Durham, CT
Gainesville, FL
Port Wentworth, GA
Manor, GA
Baxley, GA
Brunswick, GA
Glennville, GA
Manor, GA
Homerville, GA
Madison, IL
Carbondale, IL
Galesburg, IL
4-536
(continued)
-------
TABLE 4.12.2-4. (Continued)
Company
Location
Hoosier Treating Company
Kerr-McGee Chemical Corporation, FPD
Western Tar Products Corporation
Easterday Tie and Timber Company
Koppers Company, Inc.
L. L. Benton Creosoting Works
Colfax Creosoting Company
Dura-Wood Treating Company
International Paper Company, IWP Division
Madisonville Wood Preserving Company
Superior Tie and Timber
Eastern Maryland Wood Treating Company
American Wood
Brookhaven Wood Preserving Company
Kerr-McGee Chemical Corporation
Koppers Company, Inc.
Pearl River Wood Preserving Corporation
Timco, Inc.
Wood Treating, Inc.
Kerr-McGee Chemical Corporation
Atlantic Wood Industries, Inc.
General Timber, Inc.
General Wood Preserving Company, Inc.
Holcomb Creosote Company
Julian Lumber Company
Mixon Brothers Wood Preserving Company
J. H. Baxter and Company
Kerr-McGee Chemical Corporation
McCormick and Baxter Creosoting Company
Gosport, IN
Indianapolis, IN
Terre Haute, IN
Mayfield, KY
Guthrie, KY
Benton, LA
Pinesville, LA
Alexandria, LA
DeRidder, LA
Madisonville, LA
Vivian, LA
Federalsburg, MD
Richton, MS
Brookhaven, MS
Columbus, MS
Grenada, MS
Picayune, MS
Wiggins, MS
Picayune, MS
Springfield, MO
Hainesport, NJ
Sanford, NC
Leland, NC
Yadkinville, NC
Antlers, OK
Idabel, OK
Eugene, OR
The Dalles, OR
Portland, OR
4-537
(continued)
-------
TABLE 4.12.2-4. (Continued)
Company
Location
Taylor Lumber & Treating, Inc.
Burke-Parsons-Bowlby Corporation
H.P. McGinley, Inc.
Kerr-McGee Chemical Corporation
Koppers Company, Inc.
Mellot Wood Preserving Company, Inc.
Koppers Company, Inc.
Wheeler Lumber Operations
Conroe Creosoting Company
Garland Creosoting Company
Hart Creosoting Company
Hicks Post Company
Kerr-McGee Chemical Corporation
Lufkin Creosoting Company, Inc.
W. J. Smith Wood Preserving Company
AT&SF Ry Company
Texas Electric Cooperative, Inc.
Atlantic Wood Industries, Inc.
Burke-Parsons-Bowlby Corporation
Koppers Company, Inc.
Wood Preservers, Inc.
J. H. Baxter and Company
McFarland Cascade
Pacific Wood Treating Corporation
Wyckoff Company
Acme Wood Preserving, Inc.
Appalachian Timber Services, Inc.
Burke-Parsons-Bowlby Corporation
Sheridan, OR
DuBois, PA
McAlisterville, PA
Avoca, PA
Montgomery, PA
Needmore, PA
Florence, SC
Whitewood, SD
Conroe, TX
Longview, TX
Jasper, TX
Alto, TX
Texarkana, TX
Lufkin, TX
Denison, TX
Somerville, TX
Jasper, TX
Portsmouth, VA
Goshen, VA
Salem, VA
Warsaw, VA
Arlington, WA
Tacoma, WA
Ridgefield, WA
Seattle, WA
Princeton, WV
Sutton, WV
Spencer, WV
4-538
(continued)
-------
TABLE 4.12.2-4. (Continued)
Company Location
Koppers Company, Inc. Green Spring, WV
Koppers Company, Inc. Superior, WI
Webster Wood Preserving Company Bangor, WI
NOTE: This list is subject to change as market conditions change, facility ownership changes, plants are
closed down, etc. The reader should verify the existence of specific facilities by consulting current
lists and/or the plants themselves. The level of POM emissions from any given facility is a
function of variables such as capacity, throughput, and control measures, and should be determined
through direct contacts with plant personnel.
Source: Micklewright, 1990.
4-539
-------
SECTION 4.12.2 REFERENCES
Andersson, K. et al. "Sampling and Analysis of Particulate and Gaseous Polycyclic Aromatic
Hydrocarbons from Coal Tar Sources in the Working Environment." Chemosphere.
12(2): 197-207. 1983.
Grumpier, E., U.S. Environmental Protection Agency, telephone conversation with P.A. Keller,
Radian Corporation. "Wood Treatment MACT Development Preliminary Data." June 16, 1994.
Ebasco Services, Inc. Final Emission Test Report. Emission Testing Program. Koppers
Superfund Site. Oroville. California. EPA Contract No. 68-01-7250. pp. 1.1-1.5, 3.1-3.13, and
6.1-6.39. December 1989.
Koppers Industries, Inc. "AB2588 Emission Test Program." Oroville, California. 7 pp.
October 8-12, 1990.
Micklewright, J.T. A List of Wood Preserving Plants in the United States including Address.
Location, and Number of Pressure Cylinders. American Wood Preservers Institute, Vienna,
Virginia. 53pp. 1990.
U.S. Department of Agriculture. The Biologic and Economic Assessment of Pentachlorophenol.
Inorganic Arsenical, and Creosote - Volume I: Wood Preservatives. U.S. Department of
Agriculture, Washington, DC. USDA Technical Bulletin No. 1658-1. November 1980.
U.S. Environmental Protection Agency. Title ffl. Section 313: Release Reporting Guidance.
Estimating Chemical Releases from Wood Preserving Operations. Office of Pesticides and
Toxic Substances, Washington, DC. EPA-560/4-88-004p. llpp. February 1988.
Vaught, C.C., and R.L. Nicholson. Evaluation of Emission Sources from Creosote Wood
Treatment Operations. Prepared for U.S. Environmental Protection Agency, Control Technology
Center, Research Triangle, Park, North Carolina. EPA-450/3-89-028. 33 pp. June 1989.
Wallingford, K.M., and S.S. Que Hee. "Occupational Exposure to Benzo(e)pyrene." In:
Polynuclear Aromatic Hydrocarbons: Mechanisms. Methods, and Metabolism. Proceedings of
the Eighth International Symposium on Polynuclear Aromatic Hydrocarbons. Columbus,
Ohio, 1983. M. Cooke and A.J. Dennis, eds. Battelle Press, Columbus, Ohio. 1985.
Ware, P., Vulcan Chemicals, Letter to D. Beauregard, U.S. Environmental Protection Agency.
January 9, 1996.
4-540
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4.12.3 Carbon Regeneration
Process Description
Activated carbon is used primarily for adsorbing pollutants from water or air
(e.g., in industrial or municipal wastewater treatment plants). Because of increasing
environmental awareness and tighter regulations, the demand for activated carbon is increasing.
Used carbon can be regenerated (reactivated) by essentially the same process used for the original
activation. The regeneration process creates the potential for POM formation and emissions.
In the regeneration process, organics adsorbed on the carbon during use are
burned off by placing the spent carbon in continuous internally or externally fired rotary retorts
or, most commonly, in multiple-hearth furnaces. Figure 4.12.3-1 shows a cross-section of a
typical multiple-hearth furnace. In this type of furnace, the charge (carbon) is stirred and moved
from one hearth to the next-lower hearth by rotating rabble arms. For smaller-scale regeneration
operations, fluidized-bed and infrared furnaces can be used. The various furnace types used for
carbon regeneration and the approximate number of furnaces of each type are shown in
Table 4.12.3-1.
In a typical regeneration process, spent carbon in a water slurry form is fed from a
surge tank to a dewatering screw, which feeds the spent carbon to the top of the furnace. In the
furnace, the spent carbon is dried and the organics on the carbon are volatilized and burned as the
carbon is regenerated. The regenerated carbon drops from the bottom hearth of the furnace to a
quench tank and is stored as a slurry (U.S. EPA, 1987). A flow diagram of the carbon
regeneration process is shown in Figure 4.12.3-2.
A hot gas, such as steam or CO2, is introduced into the furnace at temperatures of
approximately 1,498 to 1,858°F (800 to 1,000°C), although some excess oxygen is typically
present throughout the furnace (Byers, 1991). The regeneration process is exothermic, using the
heating value of the volatile carbon plus heat supplied from supplemental fuel (e.g., natural gas).
4-541
-------
Furnace Exhaust
to Afterburner
Pyrolysis
Gases
Product
Cooling and Combustion Air
Feed Material
Figure 4.12.3-1. Cross-section of a Typical Multiple-hearth Furnace
Source: U.S. EPA, 1997.
4-542
-------
TABLE 4.12.3-1. TYPES OF EQUIPMENT USED FOR
ACTIVATED CARBON REGENERATION
Approximate No. of
Furnace Type Units in United States
Multiple-hearth <100
Fluidized-bed <20
Indirect-fired rotary kiln >50
Direct-fired rotary kiln <30
Vertical-tube type <30
Infrared-horizontal <5
Infrared-vertical 4
Source: Shuliger and Knapil, 1990.
4-543
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Refractory Lined Duct
Spent Carbon from
Industrial Wastewater
Treatment Plant Users
Afterburner
Exhaust
Ui
Dewatering
Screw
Spent Carbon
Exhaust Gas
to Atmosphere
Sodium Carbonate
Solution —
Atomizing Air
Spray
Cooler
Spray Cooler
Exhaust
Regenerated Carbon to
Industrial Wastewater
Treatment Plant Users
loler
"A
Baghouse
•I
¥
'
Stack
Baghouse
Exhaus
Regenerated
Carbon
Storage
Tanks
Baghouse
Catch
o.
oi
CO
CM
s
O
0.
O
OL
111
Figure 4.12.3-2. Process Flow Diagram of Carbon Regeneration Process
Source: U.S. EPA, 1993.
-------
A typical furnace may fire an average of 459,089 ft3/day (13,000 m3/day) of natural gas
(U.S. EPA, 1987).
Typical industrial carbon regeneration plants may process up to 109,127 Ib/day
(49,500 kg/day) of spent carbon from numerous industrial or municipal facilities that use
activated carbon for wastewater treatment (U.S. EPA, 1987). Regeneration plants may operate
24 hours per day, 7 days per week for much of the year, with periodic shutdowns for furnace
maintenance.
Emissions from carbon activation and regeneration processes contain a number of
toxic air pollutants. Regeneration has an even greater potential for producing toxic emissions
because the carbon has often been used to adsorb compounds classified as toxic air pollutants
(Byers, 1991).
The potential for POM formation exists in the high-temperature, low-oxygen
environment of the regeneration furnace. POM compounds are more likely formed from the
adsorbed organics on the spent carbon rather than from impurities in the virgin carbon.
The primary point source of emissions from the carbon regeneration process is the
furnace exhaust. These emissions are typically controlled by afterburners followed by wate:
scrubbers (U.S. EPA, 1987). The afterburner may consist of a short vertical section with natural
gas-fired burners and a long horizontal section of refractory-lined duct with no burners.
Afterburner combustion temperatures of 1,822°F (980°C) or greater and residence times in
excess of 2 seconds are typical (Byers, 1991). Temperatures greater than 1,625°F (871 °C) and
residence times longer than 0.5 seconds are recommended (U.S. EPA, 1987). There are no
available data on the destruction and removal efficiency (DRE) for an afterburner control system
in this application. However, the conditions and configuration are similar to those used for
controlling hazardous waste incinerator emissions, where DREs of 99.99 percent are typical
(Byers, 1991).
4-545
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Exhaust gases from the afterburner can be cooled by an alkaline (e.g., sodium
carbonate) spray cooler in which an atomized dilute alkaline solution is mixed with the exhaust
gas. The alkaline medium neutralizes acid gases to permit compliance with regulatory emission
limits (Byers, 1991). From the spray cooler, the exhaust gases may enter centrifugal or fabric
filter (baghouse) collectors, which are used to control paniculate and reaction products from
upstream components. Collection efficiencies of 65 percent for centrifugal collection and
99 percent for fabric filtration have been reported (Byers, 1991). The collected paniculate is
ultimately disposed of in a landfill.
Emission Factors
PAH concentrations and mass emission rates from a municipal wastewater
treatment plant carbon reactivation furnace were quantified in one test report (BTC Env., 1991).
Insufficient data were available in the report to develop PAH emission factors. The unit tested
was a reactivation furnace of unspecified design used to reactivate carbon for tertiary wastewater
treatment. The furnace was fired with natural gas, using steam from a co-located natural
gas-fired boiler. The unit was equipped with an afterburner and a scrubber. The controlled
exhaust gases from the furnace were sampled using CARB Method 429 and analyzed for specific
PAHs. The following PAHs were detected in one or more of the three sampling runs:
benz(a)anthracene, benzo(b&k)fluoranthene, chrysene, acenaphthalene, anthracene, fluoranthene,
fluorene, naphthalene, phenanthrene, and pyrene.
Source Locations
Activated carbon is used primarily to adsorb organics from water at industrial or
municipal wastewater treatment plants. Carbon regeneration may be performed at the site where
the carbon was used (on-site regeneration) or at a commercial regeneration facility that processes
spent carbon from multiple industries. Because of the large number of potential individual
locations of regeneration facilities, listing specific sites is not feasible here.
4-546
-------
SECTION 4.12.3 REFERENCES
BTC Environmental, Inc. AB-2588 Toxic Emission Testing. Orange County Water District.
10500 Ellis Avenue. Fountain Vallev. California, pp. 1-5. April 29 1991 to May 8, 1991.
Byers, W.D. Charcoal/Activated Carbon. Air Pollution Engineering Manual. Buonicore, A.J.,
and W.J. Davis, eds. Van Nostrand Reinhold, New York, New York. pp. 413-416. 1991.
Schuliger, W.G., and L.G. Knapil. "Reactivation Systems." In: Sunday Seminar. American
Waterworks Association Annual Conference, June 1990.
U.S. Environmental Protection Agency. Locating and Estimation Air Emissions from Sources of
Dioxins and Furans. Prepared for U.S. Environmental Protection Agency, Emission Inventory
Branch, Research Triangle Park, North Carolina. EPA-454/R-97-003. 1997.
U.S. Environmental Protection Agency. National Dioxin Study. Tier 4 -Combustion Sources.
Final Test Report - Site 9. Carbon Regeneration Furnace CRF-A. Office of Air Quality Planning
and Standards, Research Triangle Park, North Carolina. EPA-450/4-84-014r. pp. 3-1 to 3-2.
April 1987.
4-547
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4.12.4 Cigarette Smoke
Process Description
The smoke produced from burning cigarettes and other tobacco products has been
intensively researched in the last three decades. Previously, the concern over health risks from
cigarette smoke was focused on the smoker. Recently the impact of environmental tobacco
smoke (ETS), also known as passive smoke or "second-hand" smoke, on non-smokers has also
been investigated. The preliminary indications are that ETS presents a health problem for
non-smokers that approaches the impact of cigarette smoke on the smoker (National Academy of
Sciences, 1989).
The impacts of ETS have primarily been viewed as a component of the issue of
indoor air quality. However, ETS represents one of the many small sources contributing POM to
the outdoor urban atmosphere. One estimate is that cigarette smoke accounted for about
2.7 percent of the fine organic aerosol emission in the Los Angeles area atmosphere in 1982
(Rogge et al., 1994). This contribution can be expected to grow as smoking is increasingly
restricted to the outdoors at many facilities and workplaces.
Emission Factors
A recent study was conducted to trace cigarette smoke PM in outdoor ambient air
(Rogge et al., 1994). Tracer compounds were identified in cigarette smoke that demonstrated the
following necessary features: the compound is fairly stable in the atmosphere; the compound is
present in a known ratio to the cigarette smoke PM mass concentration; and the compound is
distinguishable from PM from other anthropogenic or biogenic sources. The class of PAH
compounds met all three of these conditions and were considered suitable tracer compounds for
ETS.
Cigarette smoke was sampled and analyzed for PAH and other suitable tracer
compounds. The exhaled mainstream smoke and sidestream smoke (the smoke from the
4-548
-------
cigarette that is not exhaled) from human smokers was sampled in a specially designed, vertically
oriented, dilution tunnel, which allowed sufficient time for condensible organic compounds
emitted in the vapor phase to equilibrate with smoke particles prior to sampling. Hence, only the
PM in the smoke was collected, and the PAH adsorbed onto the PM was analyzed. This test
design most closely approximates the conditions and the form of the PAH that would be
expected in the ambient air. Based on these tests, emission factors for PAH in cigarette smoke
that are released to the environment are reported in Table 4.12.4-1.
Source Location
Because cigarette smoke is emitted from area sources, the location of the
emissions need not be specified.
4-549
-------
TABLE 4.12.4-1. PAH EMISSION FACTORS FOR CIGARETTE SMOKE
-f.
o
SCC Number Emission Source Control Device Pollutant
A-28-10-XXX-XXX Cigarette Uncontrolled Benz(a)anthracene
Chrysene/Triphenylene
Anthracene
Fluoranthene
Phcnanthrene
Pyrene
2-Phenylnaphthalene
Benzacenaphthylene
Benzo(a)fluorene/
Benzo(b)fluorene
Dimethylfluoranthenes/
Dimethylpyrenes
Methylbenz(a)anthracenes/
Methylchrysenes/
Methyltriphenylenes
Average Emission Factor
in Ib/cigarette
(kg/cigarette)a
6.0E-IO
(2.7E-10)
1.5E-09
(6.7E-10)
1.7E-09
(7.6E-10)
2.1E-09
(9.5E 10)
5.8E-09
(2.6E-09)
2.2E-09
(l.OE-09)
8.2E-10
(3.7E-10)
6.6E-10
(3.0E-10)
1.2E-09
(5.4E-10)
1.2E-09
(5.5E-10)
1.5E-09
(6.9E-10)
Emission Factor
Rating
A
A
A
A
A
A
A
A
A
A
A
(continued)
-------
TABLE 4.12.4-1. (Continued)
SCC Number Emission Source
A-28-10-XXX-XXX Cigarette (continued)
(continued)
Control Device Pollutant
Uncontrolled (continued) Methylfluoranthenes/
Methylpyrenes
Melhylphenanthrenes/
Methylanthracenes
Average Emission Factor
in Ib/cigarette
(kg/cigarette)"
2.9E-09
(1.3E-09)
7.7E-09
(3.5E-09)
Emission Factor
Rating
A
A
"Emission factors in Ib (kg) per cigarette smoked.
Source: Roggeetal., 1994.
-------
SECTION 4.12.4 REFERENCES
National Academy of Sciences. Environmental Tobacco Smoke: Measuring Exposure and
Assessing Health Effects. National Academy Press, Washington, DC. 1989.
Rogge, W.F., L.M. Hildemann, M.A. Mazurek, and G.R. Cass. "Sources of Fine Organic
Aerosol: 6. Cigarette Smoke in the Urban Atmosphere." Environmental Science and
Technology, Volume 28, No. 7, pp. 1375-1388. 1994.
4-552
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4.12.5 Wood Charcoal Production
Process Description
Charcoal, which is primarily used for outdoor cooking, is manufactured by the
pyrolysis of carbonaceous raw materials, mainly medium to dense hardwoods such as beech,
birch, maple, hickory, and oak. Softwoods, sawdust, nutshells, fruit pits, and vegetable wastes
are also used in the pyrolysis process. The high-temperature (842 to 950°F [450 to 510°C])
pyrolysis of wood materials is a potential means of generating POM emissions (Kelly, 1983).
Hardwood charcoal is manufactured by a four-step pyrolysis process. Heat is
applied to the wood and as the temperature rises to 212°F (100°C), water and highly volatile
hydrocarbons are distilled off. The wood temperature remains at approximately 100°C until the
moisture content of the wood has been removed. At this time the volume of distillate production
declines and the wood temperature begins to climb. During the next stage, the wood temperature
rises with heat input to approximately 527°F (275 °C) and hydrocarbon distillate yield increases.
As the third stage begins (at approximately 275 °C), external application of heat is no longer
required because the carbonization reactions become exothermic. During this stage, the wood
temperature rises to 662°F (350°C), and the bulk of hydrocarbon distillates are produced. \t
approximately 350°C, exothermic pyrolysis ends, and during the final stage, heat is again
applied, raising the wood temperature to 752 to 932 °F (400 to 500 °C) to remove more of the less
volatile, materials from the product charcoal.
Currently, there are two predominant vessel types used to manufacture wood
charcoal: the Missouri-type batch kiln and the continuous Herreshoff furnace.
Missouri-type Batch Kiln-The batch process and kiln account for about 45 percent of national
wood charcoal production. The Missouri-type kiln, shown in Figure 4.12.5-1, is typically
constructed of concrete (Moscowitz, 1978) and normally processes about 45 to 50 cords of wood
in a 10- to 25-day cycle. A typical cycle may be structured as follows:
4-553
-------
Lft
Lft
TJ
U)
(3
K.
UJ
Figure 4.12.5-1. Missouri-type Charcoal Kiln
Source: Moscowitz, 1978,
-------
• 1 to 2 days: load wood;
• 5 to 8 days: pyrolysis;
• 10 to 14 days: cool; and
• 1 to 2 days: unload charcoal.
After the wood is manually loaded into the kiln, a fire is started, usually at the
bottom center of the kiln, by igniting easily combustible materials placed at this point during the
loading. Ignition patterns are generally similar for all types of kilns. During ignition, a large
amount of air is necessary for the rapid combustion of the starting fuels to ensure the heat level
needed for pyrolysis. This air is supplied through groundline ports in the kiln side walls or
through temporary openings under the kiln door. In some cases, the kiln doors remain open until
the burn is adequately started. Auxiliary ceiling ports in some kilns serve as temporary stacks
and aid ignition by causing greater amounts of air to be drawn into the kiln through the air ports.
They also aid in removal of smoke from the kiln (Moscowitz, 1978).
Satisfactory carbonization depends primarily on the maintenance of proper
burning conditions in the pyrolysis zone. Sufficient heat must be generated first to dry the wood
and then to maintain the temperatures necessary for efficient carbonization. At the same time,
the burning must be limited so that only sufficient heat is present to produce good charcoal.
Temperature control is attained by varying the size of the air port openings providing air for
combustion of wood volatiles (Moscowitz, 1978).
For the production of good-quality charcoal, kiln temperatures from about 842 to
950°F (450 to 510°C) are required. Prolonged higher temperatures will reduce the yield of
charcoal without necessarily upgrading it for recreational use. On the other hand, if pyrolysis
temperatures remain low, the charcoal may be too smoky for domestic use, and larger than
normal amounts of brands (partially charred wood) will be produced (Moscowitz, 1978).
When pyrolysis has been completed, all air ports are sealed for the start of the
cooling cycle. To prevent the development of gas pressure in the kiln, after the ports are sealed,
4-555
-------
the stacks remain open until smoking has practically stopped. Stacks can usually be sealed
within 1 to 2 hours after the air ports are closed. The kiln is allowed to cool for about 10 to
14 days before removing the charcoal. Yields of approximately 25 percent are achieved
(Moscowitz, 1978).
The required pyrolysis time and resultant POM emissions from a Missouri-type
batch kiln vary with kiln capacity, operational practices, wood type, and wood moisture content.
Process reaction gases containing POM are exhausted from the kiln in stacks that run along the
side walls of the vessel (Kelly, 1983; Moscowitz, 1978). The charcoal product of a batch kiln
process is either sold directly or made into briquettes for sale.
Herreshoff Multiple-Hearth Furnace-Continuous charcoal production is accomplished in
Herreshoff multiple-hearth furnaces. The use of continuous multiple-hearth units for charcoal
production has increased because of the following advantages of the units:
• Lower labor requirements than kiln operations, where manual loading and
unloading is needed. Only one man per shift is required for continuous
facilities.
• Consistent yield and quality charcoal with easy control of product volatile
and fixed carbon content.
• Feed of multiple forms of wood waste.
• Offgases easily collected for further processing.
The typical feedstock capacity of continuous wood charcoal furnaces is
2.75 tons/hr (2.5 Mg/hr).
The operating principles of the Herreshoff furnace (Figure 4.12.5-2 ) are relatively
simple. Passing up through the center of the furnace is a shaft to which are attached 2 to 4 rabble
arms for each hearth. As the shaft turns, the hogged wood material resting on the hearth floors is
continually agitated, exposing fresh material to the hot gases being evolved. A further function
of the rabble arms is to move material through the furnace. On alternate hearths, the teeth
4-556
-------
Furnace Exhaust
to Afterburner
Pyrolysis
Gases
Feed Material
Product
Cooling and Combustion Air
•B
o
Figure 4.12.5-2. Multiple-Hearth Furnace for Charcoal Production
Source: Moscowitz, 1978.
4-557
-------
are canted to spiral the material from the shaft toward the outside wall of the furnace or from the
outside wall toward the center shaft. Around the center shaft is an annular space through which
material drops on alternate hearths, while on the remaining hearths material drops through holes
in the outer periphery of the hearth floor. In this way, material fed at the top of the furnace
moves alternately across the hearths at increasing temperatures until it discharges from the floor
of the bottom hearth.
Charcoal exiting the furnace is cooled by water sprays and water jacketing on a
cooler. These sprays are controlled automatically by a temperature regulator set for a given
charcoal temperature. As with batch kilns, the charcoal product of continuous kilns is either sold
directly or further processed to briquettes for sale (Moscowitz, 1978).
Initial heat for startup is provided by oil- or gas-fired burners mounted in the sides
of the hearths. When the appropriate furnace temperature has been attained, the auxiliary fuel
ceases, and combustion air is used to ignite the evolving wood gases to maintain furnace
temperature. Furnace temperatures range between 896 to 1,202°F (480 to 650°C). Exhaust
gases from the charcoal production process are: (1) vented to the atmosphere or to controls
through stacks located on top of the furnace, (2) used as a heat source for predrying of feed
material and drying of briquettes produced at an adjacent vessel, or (3) burned in a waste heat
boiler to produce steam (Kelly, 1983).
A 1978 EPA investigation into wood charcoal production indicated that many of
the batch kilns are relatively old and many, particularly smaller kilns, are uncontrolled
(Kelly, 1983; Moscowitz, 1978). In general, the control of emissions, including POM, from
batch wood charcoal kilns is complicated by the cyclical nature of the process. Throughout the
cycle, both emission composition and flow rate change. Direct-fired afterburners for the
destruction of hydrocarbons have been suggested as the most feasible control system; however,
these devices would require an auxiliary fuel such as natural gas. Economic analyses have
indicated that for typical batch kilns, the operation of afterburners for emissions control would
cause firms to lose money (Moscowitz, 1978). With the combustion of auxiliary fuel of any type,
a potential is also created for additional POM emissions. No information is available on the
4-558
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proportion of batch kilns with afterburner controls or the effect of afterburner use on POM
emissions (Kelly, 1983).
Continuous wood charcoal furnaces are predominantly controlled by direct-fired
afterburners (Kelly, 1983; Moscowitz, 1978). Auxiliary fuel firing is required in continuous
furnace afterburners only during startup or process upsets because of the generally higher heating
value of continuous furnace exhaust gases. One facility is using an incinerator to control furnace
emissions (Moscowitz, 1978).
Emission Factors
POM emission factor data are available in the literature only for a Missouri-type
batch kiln (Kelly, 1983). Five sampling runs were made, and total uncontrolled POM emissions
averaged 0.007 Ib/ton (3.5 g/Mg) of charcoal produced. Sources and Emissions of Polycyclic
Organic Matter indicates that the POM samples from these tests were obtained using a modified
Method 5 procedure and sample analysis was performed by gas chromatography (Kelly, 1983).
Benz(c)phenanthrene and benzo(a)pyrene were identified as constituents of total POM emissions.
Four other POM compounds, dibenz(a,h)anthracene, 3-dimethylcholanthrene, 7,12-dimethyl-
benz(a)anthracene, and 3,4,5,6-dibenzocarbazole, were specifically analyzed for but were not
detected in any of the samples (Kelly, 1983).
The author of Sources and Emissions of Polycyclic Organic Matter note? that the
results of the batch kiln emission tests might be of questionable value because of the difficulty of
sampling the kiln and "the improvisational sampling techniques" used (Kelly, 1983). No
estimate of the accuracy of the test results was provided.
Source Locations
A current list of wood charcoal manufacturing facilities in the United States was
not available in statistical references or through the Barbecue Industry Association (BIA) at the
time this document was prepared. According to a survey conducted by EPA in 1978, there were
4-559
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over 100 wood charcoal manufacturing facilities in the United States, located in 24 states,
primarily Missouri, Arkansas, and several southeastern states (Moscowitz, 1978). Information
and contacts for specific member facility locations may be obtained through the BIA
(708-369-2404).
4-560
-------
SECTION 4.12.5 REFERENCES
Kelly, ME. Sources and Emissions of Polycyclic Organic Matter. U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina. EPA Report No. 450/5-83-01 Ob.
pp. 5-89 to 5-93. 1983.
Moscowitz, C.W. Source Assessment: Charcoal Manufacturing - State-of- the-Art.
U.S. Environmental Protection Agency, Industrial Environmental Research Laboratory, Research
Triangle Park, North Carolina. EPA Report No. 600/2-78-004z. December 1978.
4-561
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4.12.6 Crematories
Process Description
Crematory incinerators used for human cremation at funeral homes, mortuaries,
cemeteries. Crematories are normally of an excess air design, and utilize secondary chamber
(afterburner) and primary chamber (ignition) burners fueled by liquified petroleum (LP) gas or
natural gas. Burner capacities are generally between 750,000 and 1,500,000 Btu per hour per
burner. Later model units have burner modulation capability to regulate chamber temperatures
and conserve fuel. Incineration rates range from 100 to 250 Ib of remains per hour.
Preheating and a minimum secondary chamber temperature, typically ranging
from 1,400°F to 1,800°F, may be requirements. Although not suitable for this batch load type of
incinerator, the same requirements are occasionally applied to the primary chamber.
The human remains and cremation container, generally made of cardboard or
wood are loaded onto the primary chamber hearth and the primary burner is ignited to begin the
cremation process. The remains may be raked at the midpoint of the cremation to uncover
unburned material and speed the process. The average cremation takes from 1.5 to 3 hours, after
which the incinerator is allowed to cool for a period of at least 30 minutes so that the remains can
be swept from the hearth (Springer, 1996).
Emission Factors
Evaluation tests on two propane-fired crematories at a cemetery in California were
conducted through a cooperative effort with the Sacramento Metropolitan Air Quality
Management District to determine HAP emissions from a crematory (ERC-39). The units were
calibrated to operate at a maximum of 1.45 MMBtu per hour. Emissions testing was performed
over a two-week period. Thirty-six bodies were cremated during the test period, which equates
to two bodies per crematory per day for nine days. The body and cardboard weights and wood
process rates for each test per crematory were reported.
4-562
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Sampling, recovery, and analysis for PAH were performed in accordance with
CARB Method 429, which is based on the use of the EPA Modified Method 5 sampling train.
Data from stack gas measurements from each of the nine types of tests performed during the
evaluation program were tabulated and reported. Emission factors developed from these data are
presented in Table 4.12.6-1.
Source Locations
In 1991, there were about 400,500 cremations in more than 1,000 crematories
located throughout the United States. Table 4.12.6-2 lists the number of crematories located in
each state and the estimated number of cremations performed in each State (CANA, 1992).
4-563
-------
TABLE 4.12.6-1. POM EMISSION FACTORS FOR CREMATORIES
SCC Number Emission Source Control Device Pollutant
3-15-021-01 Crematory Stack Uncontrolled Acenaphthene
Acenaphthylene
Anthracene
Fluoranthene
Fluorene
Naphthalene
Phenanthrene
Pyrene
Average Emission
Factor in Ib/body
(kg/body)"
1.11E-07
(5.02E-08)
1.22E-07
(5.54E-08)
3.24E-07
(I.47E-07)
2.05E-07
(9.31E-08)
4.17E-07
(1.89E-07)
6.84E-05
(3.10E-05)
2.29E-06
(1.04E-06)
1.61E-07
(7.33E-08)
Emission Factor
Rating
E
E
E
E
E
E
E
E
Note: Average weight per body incinerated: body =141 Ib (64 kg); wrapping material = 4 Ib (2 kg) cardboard, 3 Ib (1.4 kg) wood.
"Emission factors in Ib (kg) per body incinerated.
Source: ERC-39.
-------
TABLE 4.12.6-2. 1991 U.S. CREMATORY LOCATIONS BY STATE
State
Alabama
Alaska
Arizona
Arkansas
California
Colorado
Connecticut
Delaware
District of Columbia
Florida
Georgia
Hawaii
Idaho
Illinois
Indiana
Iowa
Kansas
Kentucky
Louisiana
Maine
Maryland
Massachusetts
Michigan
Minnesota
Mississippi
Missouri
No. of
Crematories
6
7
26
13
141
28
10
4
1
95
14
10
12
44
21
15
10
5
6
4
17
13
38
18
4
19
No. of
Cremations3
1,138
790
10,189
1,787
86,374
7,432
4,260
1,165
b
46,775
2,684
3,495
1,949
12,083
3,636
2,241
1,559
1,192
2,656
1,853
5,587
8,104
13,431
5,662
450
4,637
State
Montana
Nebraska
Nevada
New Hampshire
New Jersey
New Mexico
New York
North Carolina
North Dakota
Ohio
Oklahoma
Oregon
Pennsylvania
Rhode Island
South Carolina
South Dakota
Tennessee
Texas
Utah
Vermont
Virginia
Washington
West Virginia
Wisconsin
Wyoming
No. of
Crematories
12
6
11
6
16
9
40
24
1
41
9
34
44
5
10
4
8
36
5
5
25
46
6
29
2
No. of
Cremations*
2,502
1,139
5,009
1,842
14,427
2,134
23,946
4,749
b
12,552
1,372
9,020
12,153
1,842
1,764
b
1,712
9,340
769
1,570
6,097
15.673
582
5,541
b
a 1990 data; 1991 data unavailable.
bNo information available.
Source: CANA, 1992.
4-565
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SECTION 4.12.6 REFERENCES
Cremation Association of North America (CANA). "Cremation Statistics from Cremationist
Journal." Compiled by CANA. 1992.
ERC-39, California Air Resources Board. Confidential Report.
Springer, J.M., Cremation Association of North America, Letter to D. Beauregard,
U.S. Environmental Protection Agency. January 31, 1996.
4-566
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4.12.7 Gasoline Distribution
Process Description
Gasoline distribution activities represent potential emission sources of one PAH,
naphthalene. Because the naphthalene content of gasoline vapors ranges from 0.1 to 1.5 percent,
with an average of about 0.5 percent, total hydrocarbon emissions from storage tanks, gasoline
transfer, and vehicle fueling will include emissions of naphthalene (U.S. EPA, 1994a). This
section lists the sources and factors for naphthalene emissions from gasoline distribution and
marketing operations. Also, even though gasoline distribution represents a notable potential
source of naphthalene emissions, because only one PAH is associated with gasoline distribution,
the discussion has been kept brief in this miscellaneous section. The references may be
consulted for a more detailed description of processes and controls.
The gasoline distribution network in the United States operates with the following
equipment and facilities:
• Pipelines;
• Tanker ships and barges;
• Tank trucks and railcars;
• Bulk terminals;
• Bulk plants; and
• Service stations.
Gasoline is delivered from the petroleum refinery to bulk terminals by way of
pipeline, tanker ship, or barge. Bulk terminals may also receive petroleum products from other
terminals. From the bulk terminal, petroleum products (including gasoline) are usually
distributed by tank trucks to bulk plants. Both bulk terminals and bulk plants deliver gasoline to
private, commercial, and retail customers (i.e., service stations). Daily product throughput at a
4-567
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bulk terminal averages about 250,000 gallons (950,000 liters), in contrast to about 5,000 gallons
(19,000 liters) for an average size bulk plant (U.S. EPA, 1994a).
Gasoline vapors and the naphthalene they contain may be emitted at each step in
the network. Controls that have been devised include the following:
Vapor recovery and collection or destruction for marine tank vessel
loading and unloading;
Closed vapor balancing systems for gasoline transfer to and from
tank trucks;
Internal and external floating roof tanks; and
Control systems on service station equipment and/or on board
automobiles and other vehicles (U.S. EPA, 1994a).
A NESHAP for the gasoline distribution source category was promulgated on
December 14, 1994. Bulk terminals and pipeline breakout stations are the only kinds of sources
in the category that were determined to be major and that are covered by the rule. The gasoline
distribution NESHAP establishes MACT for storage vessels, loading racks, leaks from piping
and equipment, and vapor leakage from sealed cargo tanks during loading (59 FR 64303). The
MACT for the different emission points includes some of the control techniques listed above.
Two sets of standards for marine tank vessel loading and unloading operations
were proposed on May 13, 1994 (59 FR 25004). One set of standards was proposed under
Section 183(f) of the CAA and requires the application of reasonably available control
technology (RACT) for VOC and HAP. The other set of standards is the proposed NESHAP for
the source category, which establishes MACT for emissions that are directly caused by the
loading and unloading of bulk liquids at points where marine terminal equipment is connected to
marine vessel sources. The MACT that was selected is the vapor recovery and reduction
technique listed above (59 FR 64303).
4-568
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Emission Factors
Naphthalene emission factors are presented in Table 4.12.7-1. Most were derived
by multiplying the percent fraction of naphthalene reported to be in the gasoline vapors by the
VOC emission factors available in EPA's AP-42 document for gasoline distribution and
marketing activities (U.S. EPA, 1995).
VOC emission factors for equipment leaks (i.e., emissions from leaking pump
seals, valves, connectors loading arm valves, open-ended lines, and other points in the gasoline
distribution network) were developed for the gasoline distribution NESHAP, but not in a form
appropriate for this document (U.S. EPA, 1994b). Emissions from equipment leaks are not
calculated based on gasoline throughput, but rather on the number of valves, connectors, etc.,
present. If the total number of leaking points at a facility is known, the factors in the reference
can be used to estimate emissions. Similarly, emission factors for storage tanks at pipeline
breakout stations, and bulk terminals and plants are not provided because there is no single factor
that applies. Rather, the equations in EPA's AP-42 document for calculating liquid organic
storage emissions can be used with the specific parameters for a particular storage tank, such as
diameter, height, etc.
It should be emphasized that the fraction of naphthalene reported in gasoline
vapor is an average value; more precise estimates of naphthalene emissions must take into
account the specific blend of gasoline and possibly the area of the country and time of the year
when the gasoline distribution activity is taking place. The only data available for this source
category are for uncontrolled operations. However, this does not indicate that the source
category is completely uncontrolled. Controls have been in place for gasoline distribution in the
majority of ozone non-attainment areas since 1980. When controls specified by the NESHAP are
in full effect, emissions of naphthalene and other hydrocarbons should be decreased substantially.
4-569
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TABLE 4.12.7-1. NAPHTHALENE EMISSION FACTORS FOR GASOLINE DISTRIBUTION
SCC Number
Bulk Terminals and Bulk Plants:
4-06-001-31,
-32, -33, -34, -35
4-06-001-36,
-37, -38, -39, -40
4-06-001-41,
-42, -43, -44, -45, -46
4-06-001-62
u» 4-06-001-62
c*
4-06-001-63
4-06-001-63
Marine Vessel Sources:
4-06-002-39
4-06-002-40
4-06-002-40
4-06-002-42,
-54. -55. -56. -57
Emission Source
Tank Car and Truck Submerged Loading: Normal Service
Tank Car and Truck Splash Loading: Normal Service
Tank Car and Truck Submerged and Splash Loading: Vapor
Balance Service
Tank Car and Truck Transit: Loaded, Typical
Tank Car and Truck Transit: Loaded, Extreme
Tank Car and Truck Transit: Return With Vapor, Typical
Tank Car and Truck Transit: Return With Vapor, Extreme
Tanker Ballasting
Ship/Ocean Barge Loading: Typical Situation, Any Cargo
Barge Loading: Typical Situation, Any Cargo
Transit for 1 Week
Control Device
Uncontrolled
Uncontrolled
Uncontrolled
Uncontrolled
Uncontrolled
Uncontrolled
Uncontrolled
Uncontrolled
Uncontrolled
Uncontrolled
Uncontrolled
Naphthalene
Emission Factor
in Ib/gal
(kg/I)
2.5E-05
(3.0E-06)a
6.0E-05
(7.2E-06)a
4.0E-05
(4.9E-06)8
0-5.0E-08
(0-6.0E-09)a
0-4.0E-07
(0-4.8E-08)a
0-5.5E-07
(0-6.6E-08)a
0-1.8E-06
(0-2.2E-07)a
4.0E-06
(5.0E-07)a
9.0E-06
(l.lE-06)a-c
1.7E-05
(2.0E-06)a'c
1.4E-05
(1.6E-06)a
Emission
Factor Rating
B
B
B
b
b
b
b
B
D
D
E
(continued)
-------
TABLE 4.12.7-1. (Continued)
SCC Number
Service Station Operations:
4-06-003-01
4-06-003-02
4-06-003-06
4-06-003-07
4-06-006-01
4-06-006-03
4-06-006-02
Emission Source
Underground Tank: Splash filling
Underground Tank: Submerged Filling
Underground Tank: Balanced Submerged Filling
Underground Tank: Breathing and Emptying
Vehicle Refueling: Displacement Losses
Vehicle Refueling: Displacement Losses
Vehicle Refueling: Spillage
Control Device
Uncontrolled
Uncontrolled
Uncontrolled
Uncontrolled
Uncontrolled
Stage II Vapor
Control
Uncontrolled
Naphthalene
Emission Factor
in Ib/gal
(kg/1)
5.8E-05
(6.9E-06)d
3.6E-05
(4.4E-06)d
1.5E-06
(1.6E-07)d
5.0E-06
(6.0E-07)d
5.5E-05
(6.6E-06)d
5.5E-06
(6.6E-07)d
3.5E-06
(4.0E-07)d
Emission
Factor Rating
B
B
B
D
b
b
D
"Emission factors in Ib/gal (kg/1) of gasoline loaded.
No emission factor rating has been assigned.
°Ocean barges have a compartment depth of 40 feet; barges have compartment depths of 10-12 feet.
dEmission factors in Ib/gal (kg/1) of gasoline throughput.
Source: U.S. EPA, 1995; U.S. EPA, 1994a.
-------
Source Locations
Because the sources of emissions in gasoline distribution are so widespread,
individual locations are not identified.
4-572
-------
SECTION 4.12.7 REFERENCES
Federal Register. Marine Tank Vessel Loading and Unloading Operations and NESHAP for
Marine Tank Vessel Loading and Unloading Operations, Notice of Proposed Rulemaking.
59 FR 25004. Government Printing Office, Washington, D.C., May 13, 1994a.
Federal Register. NESHAP for Source Categories: Gasoline Distribution (Stage I), Final Rule.
59 FR 64303. Government Printing Office, Washington, D.C. December 14, 1994b.
U.S. Environmental Protection Agency. Compilation of Air Pollutant Emission Factors.
Volume I: Stationary Point and Area Sources. AP-42, Fifth Edition. Office of Air Quality
Planning and Standards, Research Triangle Park, North Carolina, pp. 5.2-1 to 5.2-17. 1995.
U.S. Environmental Protection Agency. Gasoline Distribution Industry (Stage D - Background
Information Document for Proposed Standards. Office of Air Quality Planning and Standards,
Research Triangle Park, North Carolina. EPA-453/R-94-002a. January 1994a.
U.S. Environmental Protection Agency. Gasoline Distribution Industry (Stage D - Background
Information Document for Promulgated Standards. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. EPA-453/R-94-002b. November 1994b.
4-573
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4.12.8 Rayon-based Carbon Fiber Manufacture
Process Description
Rayon-based carbon fibers are used primarily in cloth for aerospace applications,
including phenolic impregnated heat shields and in carbon-carbon composites for missile parts
and aircraft brakes (Volk, 1980). Due to their high carbon content, these fibers remain stable at
very high temperatures.
There are three steps in the production process of rayon-based carbon cloth
(Volk, 1980):
• Preparation and heat treating;
• Carbonization; and
• High heat treatment (optional).
In the preparation and heat treating step, the rayon-based cloth is heated to 390 to 660°F (200 to
360°C). Water is driven off (50 to 60 percent weight loss) during this step to form a char with
thermal stability. In the carbonization step, the cloth is heated to 1,830 to 3,630°F (1,000 to
2,000 °C), where additional weight is lost and the beginnings of a carbon layer structure is
formed. To produce a high strength rayon-based fiber, a third step is needed. The cloth is
stretched and heat treated at temperatures near 5,430°F (3,000°C) (Volk, 1980).
Emission Factors
PAH emission factors for rayon-based carbon fiber manufacturing are presented in
Table 4.12.8-1. The emission factors are based on a single tested facility. POM emissions were
sampled at the exhaust stack of a carbon fabric dryer, which is used in carbonization of heat
treated rayon. Both paniculate and vapor phase PAHs were quantified (Engineering-Science,
Inc., 1990).
4-574
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TABLE 4.12.8-1. PAH EMISSION FACTORS FOR RAYON-BASED CARBON FIBER MANUFACTURING
SCC Number Emission Source Control Device Pollutant
3-30-001-98 Carbon Furnace None Acenaphthylene
Anthracene
Fluoranthene
Fluorene
Naphthalene
4i. Phenanthrene
Ul
Pyrene
Average Emission
Factor in Ib/ton
(kg/Mg)a
1.65E-08
(8.25E-09)
1.25E-08
(6.25E-09)
2.48E-08
(1.24E-08)
6.69E-08
(3.34E-08)
1.74E-05
(8.70E-06)
8.12E-08
(4.06E-08)
2.6IE-08
(1.30E-08)
Emission
Factor Rating
D
D
D
D
D
D
D
"Emission factors are in Ib (kg) per ton (Mg) of carbonized rayon fabric produced.
Source: Engineering-Science, Inc., 1990.
-------
Source Locations
A list of U.S. producers of rayon-based carbon fibers is provided in
Table 4.12.8-2.
TABLE 4.12.8-2. RAYON-BASED CARBON FIBER MANUFACTURERS
Manufacturer
Location
Amoco Performance Products, Inc.
BP Chemicals (Hitco) Inc.
Fibers and Materials Division
Polycarbon, Inc.
Greenville, SC
Gardena, CA
Valencia, CA
Source: SRI, 1994.
4-576
-------
SECTION 4.12.8 REFERENCES
Engineering-Science, Inc. AB2588 Air Pollution Source Testing at Hitco Corporation. Gardena.
California. Pasadena, California. 1990.
SRI International. 1994 SRI Directory of Chemical Producers - United States of America.
Menlo Park, California, p. 509. 1994.
Volk, H.F. "Carbon Fibers and Fabrics." In: Kirk-Othmer Encyclopedia of Chemical
Technology. Volume 4. John Wiley and Sons, New York. p. 622. 1980.
4-577
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4.12.9 Commercial Charbroilers
Process Description
Commercial scale charbroiling is commonly practiced in the food preparation and
service industries. Meat products are charbroiled over a wood charcoal or natural gas (most
common) flame to cook them and enhance flavor. Commercial charbroilers are generally
uncontrolled or controlled by simple grease extractors.
Emission Factors
PAH emission factors for commercial scale charbroiling are presented in
Table 4.12.9-1. A single unit was tested, while broiling hamburger with a fat content ranging
from 10 to 21 percent over a natural gas flame. The broiler was equipped with an exhaust hood
and baffle-type grease extractor. Sampling for POM was conducted at the exhaust stack of the
grease extractor (Rogge et al., 1991).
Source Locations
The locations of commercial scale charbroilers are highly diffuse, and generally
correlated to population distribution.
4-578
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TABLE 4.12.9-1. PAH EMISSION FACTORS FOR COMMERCIAL CHARBROILERS
-J
VO
SCC Number Emission Source Control Device Pollutant
23-02-002-000 Exhaust Stack None Benz(a)anthracene
Benzo(a)pyrene
Benzo(ghi)perylene
Benzo(k)fluoranthene
Fluoranthene
Pyrene
Emission Factor Range
Average Emission Factor in Ib/ton
in Ib/ton (mg/kg)a (mg/kg)a
5.90E-04
(2.95E-01)
3.80E-04
(1.90E-01)
4.80E-04
(2.40E-01)
3.30E-04
(1.65E-01)
4.70E-04
(2.35E-01)
9.30E-04
(4.65E-01)
5.80E-04 -
(2.90E-01 -
-
-
1.20E-04-
(6.00E-01 -
2.40E-04 -
(1.20E-01 -
3.80E-04 -
(1.90E-01-
6.00E-04
3.00E-01)
-
-
5.40E-04
2.70E-01)
7.00E-04
3.50E-01)
1.40E-03
7.40E-01)
Emission
Factor
Rating
D
D
D
D
D
D
"Emission factors are in Ib (mg) per ton (kg) of hamburger charbroiled.
Source: U.S. EPA, 1994.
-------
SECTION 4.12.9 REFERENCES
Rogge, W. F., L. M. Holdemann, M. A. Mazurek, G. R. Cass, and B. R. T. Simonelt. "Sources
of Fine Organic Aerosol. 1. Charbroilers and Meat Cooking Operations." Environmental
Science Technology, 26:6, 1991.
U.S. Environmental Protection Agency. Factor Information Retrieval (FIRE) System Database,
Version 2.62. March 1994.
4-580
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SECTION 5.0
EMISSIONS FROM PRODUCTION AND USE OF NAPHTHALENE
Sources of atmospheric emissions of naphthalene related to its production and use
are described in this section. Although naphthalene is a POM, it is different from the other POM
species in that, similar to benzene, naphthalene is produced commercially and used as a raw
material. In contrast, the other POM species are generated as undesired byproducts; they are not
produced intentionally for any commercial use. Moreover, naphthalene is a hazardous air
pollutants (HAP) listed separately from POM in Section 112(b) of the Act. As discussed
throughout Section 4.0, naphthalene can be formed along with the other POM species and
emitted from sources other than those associated with naphthalene production and use. Where
naphthalene is generated in notable quantities, emission factors were listed along with those for
other significant POM species for that source category. However, this section is focused on
quantifying emissions specifically from the production and use of naphthalene.
Emission factors for the production processes are presented where available, and
control technologies are described. In some cases, the emissions have been estimated from
mathematical models. Hence, to estimate emissions for specific facilities and sources, it is
advisable to examine the exact nature of the process used, production volume, and control
techniques in place before applying any of the emission factors presented here.
5.1 EMISSIONS FROM NAPHTHALENE PRODUCTION
Naphthalene is produced from either coal tar (a byproduct of coal coking) or
petroleum. Approximately 90 percent of the total annual capacity of chemical-grade naphthalene
is based on coal tar as a feedstock; the remainder is derived from petroleum refinery streams. A
1985 emissions inventory indicated that 12 coke byproduct recovery plants in the United States
have the capacity to produce crude naphthalene (EPA, 1986). Other than these coke byproduct
recovery plants, three U.S. companies currently produce chemical-grade naphthalene from either
coal tar or petroleum at facilities operating with a total annual capacity of 136,000 tons
(123,000 Mg), based on various 1993 estimates (Chemical Marketing Reporter, 1993;
5-1
-------
Mannsville Chemical Products Corporation, 1993; SRI International, 1993). A few other
companies have produced chemical naphthalene in the past; however, their facilities are closed
due to market conditions.
Since the early 1970s, naphthalene capacity and production as a whole has
decreased at an average rate of about five percent per year, from 440,000 tons (400,000 Mg) in
1970 to 136,000 tons (123,000 Mg) in 1993 (Mannsville Chemical Products Corporation, 1993).
The decline in naphthalene capacity and production is primarily due to competition with
ortho-xylene as the feedstock for phthalic anhydride production, which is the major end use of
naphthalene. Because ortho-xylene is currently the preferred raw material for phthalic anhydride
manufacture, only about 15 percent of phthalic anhydride capacity in the United States is based
on naphthalene feed.
5.1.1 Naphthalene from Coal Tar
Process Description—Coke Byproduct Recovery Plants
As described in Section 4.7, naphthalene and other POM emitted throughout
byproduct coke plants are undesirable, but the recovery of naphthalene in the byproduct recovery
portion of such plants is intentional. This section describes in greater detail the portions of the
plant specifically associated with naphthalene production. A detailed flow diagram of a typical
coke byproduct recovery plant is shown in Figure 5-1 (U.S. EPA, 1984).
Naphthalene is removed from the coke oven gas stream after it leaves the
ammonia absorber. The naphthalene-containing gas is cooled in the final cooler, a tower
scrubber in which most of the naphthalene and any entrained tar and vapors are condensed by
direct contact with water, thus separating naphthalene from the gas stream before the gas is
processed further. The condensed naphthalene floats to the top of the water in the final cooler, is
skimmed and collected in open sumps as an impure, yellow-brown slurry containing about 50 to
60 percent water. Separation may be enhanced with a froth flotation separator or similar
5-2
-------
V"
U)
Ammonia
Absorber
Final
Cooler
Coki
Add Storage r
r-j—i Jk
Coal
Light-Oil
Scrubber
j~p
Coke Oven Gas
£
o.
i
o
Q.
oc
111
rigure 5-1. Coke Oven Byproduct Recovery, Representative Plant.
Tar Product
Source: U.S. EPA, 1984; U.S. EPA, 1979
-------
equipment. The naphthalene slurry may be pumped into a tank where water is removed by
gravity separation, which crystallizes the product.
The resulting crude naphthalene may be dissolved in coal tar after physical
separation and sold as a commercial feedstock for making chemical-grade naphthalene. A
typical dry coal tar processed in the United States contains approximately 8 to 10 weight percent
naphthalene. Although crude naphthalene has little market value, about 40 percent of all coke
byproduct recovery plants handle and/or process naphthalene in some manner. If the crude
naphthalene is further refined on-site, the crystallized product may be refined through drying
when the crystals are melted in a separate rectangular tank equipped with coils for either cold
water or steam circulation. After 24 hours in the vessel, a chemical-grade naphthalene is
generated.
Emission Factors—Coke Byproduct Recovery Plants
An assessment of naphthalene emissions from all potential sources was made in
1986 to ascertain whether naphthalene should be listed as a Federal HAP (U.S. EPA, 1986). As
a part of that assessment, naphthalene emissions from coke byproduct recovery plants were
estimated.
Naphthalene emissions can be expected to originate primarily from naphthalene
separation and handling in open sumps and naphthalene melting/drying tanks, however, their
quantification is difficult. Hence, a naphthalene emission factor for the overall coke byproduct
recovery plant was developed, which is based on known annual coke production, the amount of
coal tar produced from coke production, and the average naphthalene content of coal tar. This
yielded the naphthalene emission factor of 0.012 Ib/ton (0.006 kg/Mg) coke produced, which is
presented in Table 5-1. According to this emission factor, approximately 80 Mg/yr of
naphthalene were emitted in 1986 from coke byproduct recovery plants that process crude
naphthalene (53 FR 9139).
5-4
-------
TABLE 5-1. NAPHTHALENE EMISSION FACTORS FOR NAPHTHALENE PRODUCTION
SCC Number
3-03-003-15
3-03-003-15
3-03-003-53
3-03-003-36
Emission Source
Coke Byproduct Recovery Plant
Coke Byproduct Recovery Plant
Coal Tar Distillation - Process Emissions
Coal Tar Distillation - Storage Emissions
Control Device
Uncontrolled
Controlled
Uncontrolled
Uncontrolled
Naphthalene
Emission
Factor Ib/ton
(kg/Mg)
0.012
(0.006)a
0.0024
(0.00 12)a
0.478
(0.239)b
0.0454
(0.0227)b
Emission Factor
Rating0
U
U
U
u
"Emission factors in Ib/ton (kg/Mg) of coke produced.
bEmission factors in Ib/ton (kg/Mg) of naphthalene produced.
°Factors were assigned a U rating because the supporting documentation for the factors was not sufficient to establish an AP-42 rating using
AP-42 factor rating criteria.
Source: EPA, 1986.
-------
In 1986, coke byproduct recovery plants could be expected to be poorly controlled
or perhaps uncontrolled. However today, coke byproduct recovery plants are subject to a
NESHAP limiting benzene emissions. The controls required by this NESHAP, some of which
are described in Section 4.7.3, are estimated to control 80 percent or more of naphthalene
emissions. For instance, the standard stipulates that no ("zero") benzene emissions are allowed
from naphthalene processing, final coolers and final-cooler cooling towers
(40 CFR 61, Subpart L). In achieving this zero standard, naphthalene emissions are eliminated
from these points as well. Hence, the factor reported above may be reduced by 80 percent to
0.0024 Ib/ton (0.0012 kg/Mg) coke produced, which may be used as an emission factor for
controlled naphthalene emissions from coke byproduct plants.
Source Locations—Coke Byproduct Recovery Plants
As stated previously, not all coke byproduct recovery plants produce crude
naphthalene. The majority sell the coal tar containing naphthalene to other companies for further
processing. The 12 U.S. coke byproduct recovery plants that were known to handle and/or
process so-called coal tar naphthalene in 1985 are listed in Table 5-2 (U.S. EPA, 1986).
Process Description—Coal Tar Distillation
Companies that purchase coal tar do so to recover a number of different products
from the coal tar, including chemical-grade naphthalene. The general process for recovering
chemical naphthalene from coal tar is by distillation and fractionation (U.S. EPA, 1986). The
coal tar is generally distilled in pipe stills in either a batch or continuous process. The tar is
charged into a flash tank from which the vapors pass to condensers; the still bottoms and the
pitch are sent to receiving tanks. If the total distillate is condensed, the distillate is fractionated
into four fractions: light oil (which is a primary source of benzene, toluene, and xylenes), middle
oil, heavy oil, and anthracene oil.
5-6
-------
TABLE 5-2. U.S. COKE BYPRODUCT RECOVERY PLANTS
HANDLING/PROCESSING NAPHTHALENE
Plant
Location
Empire Coke
Republic Steel
National Steel
Interlake
Indiana Gas and Chemical
U.S. Steel
Rouge Steel Co.
National Steel
Bethlehem Steel
Chattanooga Coke and Chemical
Lone Stare Steel
J&L Steel (LTV Steel)
Holt, AL
Gadsden, AL
Granite City, IL
S. Chicago, IL
Terre Haute, IN
Gary, IN
Dearborne, MI
Detroit, MI
Bethlehem, PA
Chattanooga, TN
Lone Star, TX
Pittsburgh, PA
Source: U.S. EPA, 1986.
5-7
-------
The middle oil fraction, containing naphthalene, phenols, and cresols, is pumped
hot into shallow pans where it is cooled, allowing the naphthalene to crystallize. After draining,
the crystalline product is then broken up and charged into batch centrifuges. The mother liquors
are combined and sent to phenol and cresol recovery units. The naphthalene product is washed
with hot water to increase its purity before it is discharged as crude naphthalene. This material is
suitable for phthalic anhydride manufacture and is graded and sold according to its melting point.
For refined naphthalene, the crude material is further distilled. The distillate is
first washed with a hot caustic soda solution to remove phenolic compounds and then washed
with concentrated sulfuric acid to remove basic substances. To yield a refined product, the
washed naphthalene is redistilled. The distillate from the final still is either cast into forms or is
cooled and subsequently crushed. The refined material is suitable for manufacture of flakes or
pellets for insecticide use (i.e., mothballs or flakes). However, the production of refined
naphthalene from coal tar has essentially ceased in the United States due to costs of refining and
costs of disposing significant amounts of waste sludge that is generated by the process.
Emission Factors-Coal Tar Distillation
In the 1986 assessment of naphthalene emissions, emission factors for process and
storage emissions were developed from emissions inventory data available from one of the
facilities that distills naphthalene from coal tar (U.S. EPA, 1986). The facility reported its total
POM emissions and total naphthalene production. The total POM emissions were multiplied by
a reported estimate of the percent naphthalene content of POM emitted during typical
naphthalene production. This estimate of total naphthalene emissions divided by the total
naphthalene production reported by the facility yielded a naphthalene emission factor of
0.478 Ib/ton (0.239 kg/Mg) naphthalene produced for process emissions from coal tar plants,
which is presented in Table 5-1.
An emission factor for naphthalene storage at coal tar plants was similarly
calculated from emissions inventory data provided by the facility. The total storage emissions
were reported, and a naphthalene storage emission factor was calculated based on the production
5-8
-------
data from the facility. As listed in Table 5-1, the 1986 assessment presented an emission factor
of 0.0454 Ib/ton (0.0227 kg/Mg) naphthalene produced for storage emissions from coal tar
plants.
The 1986 assessment did not indicate the level of control associated with the
facility's reported process and storage emissions. Naphthalene storage vessels can be subject to
various NSPS if they meet the specified conditions. On the other hand, naphthalene storage may
escape control based on its low vapor pressure (40 CFR 60, Subpart Kb). The recently
promulgated Hazardous Organic NESHAP may require control of the process emissions from
coal tar distillation. Hence, more precise controlled naphthalene emission factors for coal tar
plants may be available in the future after these standards take effect.
Source Locations—Coal Tar Distillation
Facilities other than coke byproduct recovery plants that distill naphthalene from
coal tar account for about 90 percent of the total annual chemical-grade naphthalene capacity.
There are only two U.S. producers of chemical naphthalene in operation that use coal tar as a raw
material: Allied-Signal Inc. in Ironton, Ohio (estimated capacity: 37,500 to 59,500 tons
[34,100 to 54,100 Mg]); and Koppers Industries, Inc., in Follansbee, West Virginia (estimaied
capacity: 75,000 to 85,000 tons [68,200 to 77,300 Mg]).
5.1.2 Naphthalene from Petroleum
Process Description
The production of naphthalene from petroleum, sometimes called
petro-naphthalene, involves two principal steps. The first step is the dealkylation, either
thermally or catalytically, of a naphthalene/alkyl naphthalene-rich aromatic stream. Second, the
naphthalene produced from the dealkylation is recovered as a high-quality product, usually by
fractional distillation. Typical feedstocks may be the bottoms fraction of refinery catalytic
reformates or a narrow cut distilled and concentrated from refractory cycle oils. Another suitable
5-9
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feedstock may be the stream of naphthalene and methyl naphthalene formed in the cracking of
heavy liquids for ethylene production.
The feedstock and a hydrogen-rich gas are pumped to a dealkylation reactor. The
reactor product is quenched and is then sent to a separator from which part of the hydrogen-rich
gas is recycled and part burned as fuel. The liquid product is distilled to separate fuel gas,
gasoline, and naphthalene. The naphthalene produced by this process is usually greater than
99 percent pure and is low in sulfur content.
Emission Factors
In the 1986 assessment of naphthalene emissions from all sources, no data was
identified to develop specific emission factors for the production of petro-naphthalene. In the
absence of available data, it was assumed in that assessment that the distillation and storage
processes for manufacturing petro-naphthalene were similar to those used in coal tar distillation.
Hence, the process and storage emission factors for naphthalene production from coal tar that
were presented in the previous section were used to estimate annual emissions from
petro-naphthalene producers as well.
Source Locations
In 1993, there was only one U.S. producer of chemical naphthalene in operation
using petroleum as a raw material: Advanced Aromatics, Baytown, Texas, with a capacity of
10,000 tons (9,100 Mg) (Chemical Marketing Reporter, 1993). A number of companies that
produced naphthalene from petroleum in the past are not currently operating, but are capable of
restarting if market conditions warrant.
5.2 EMISSIONS FROM END-USES OF NAPHTHALENE
Naphthalene is used almost exclusively as an intermediate in the manufacture of
organic chemicals. The only direct use naphthalene is as a moth repellant. Total U.S.
5-10
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naphthalene consumption is approximately 120,000 to 125,000 tons (110,000 to 114,000 Mg)
(Mannsville Chemical Products Corporation, 1993). A 1992 estimate of U.S. naphthalene
consumption by end use is as follows (Mannsville Chemical Products Corporation, 1993):
• Phthalic anhydride (64 percent);
• Naphthalene sulfonates (16 percent);
• Carbamate insecticides (10 percent);
Moth repellent (7 percent); and
• Miscellaneous (3 percent).
Demand for naphthalene and consumption patterns are not expected to change significantly.
A brief description of processes in each of the five major end-uses and the
emissions estimated in the 1986 assessment is presented. The reference can be consulted for
more detailed descriptions of the different end-uses and the exact description of how emissions
for each end-use were calculated.
5.2.1 Phthalic Anhydride Production
Process Description
The overwhelming majority of naphthalene produced is consumed in the
manufacture of phthalic anhydride. Phthalic anhydride is derived from one of two raw materials,
naphthalene or ortho-xylene. For many years, coal tar naphthalene was the only raw material
used for phthalic anhydride production. However, ortho-xylene has gradually replaced
naphthalene as the principal feedstock for phthalic anhydride manufacture; today, only about
15 percent of phthalic anhydride is derived from naphthalene (Mannsville Chemical Products
Corporation, 1993).
5-11
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Phthalic anhydride production entails two steps: oxidation and refining. In the
oxidation process, coal tar naphthalene and/or o-xylene is vaporized, mixed with air, and fed to
the reactors where it is catalytically converted to phthalic acid and other byproducts. It is
expected that 100 percent of the feedstock is converted to product so that there are no processing
emissions, only storage and fugitive emissions when naphthalene is transferred. Reactor offgases
are cooled and sent to a bank of six switch condensers, which capture and solidify the product.
According to a preset cycle, one of the condensers is taken out of line and heated to melt out the
crude acid which is then transferred to storage. Condenser offgases may be scrubbed using
venturi and packed-bed scrubbers before release to the atmosphere.
Phthalic anhydride refining consists of crude storage, decomposing,
predistillation, stripping, refining, and refined storage. No naphthalene emissions are expected
from the refining step, because all naphthalene is converted. Phthalic anhydride (99.8 percent
pure) is then sold or used in polyester production, as a plasticizer, for alkyd resins, and other
miscellaneous uses and exports.
Emission Factors
Little or no information is available on naphthalene emission sources from the
production of phthalic anhydride. However, all of the end-use industries and the processes
involving the use of naphthalene can be considered typical of those found in the synthetic organic
chemical manufacturing industries (SOCMI). Hence, emissions can be assumed to originate
from three sources: production, fugitive points or equipment leaks, and naphthalene storage.
Thus, with the lack of specific data, in the 1986 assessment of naphthalene emissions from all
sources, emissions from these various end-uses were estimated using general equipment leak
emission factors for the SOCMI, storage vessel emission factors from the EPA's AP-42
document, and the estimate that 0.034 percent of total naphthalene consumed during production
each year is emitted to the air. It was estimated that the use of naphthalene to produce phthalic
anhydride resulted in emissions of 60 tons (55 Mg) of naphthalene in 1986 (U.S. EPA, 1986).
5-12
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Source Locations
Since the 1986 assessment, Koppers Company, Cicero, Illinois, has been the only
operating naphthalene-based phthalic anhydride plant in the United States. The Koppers facility
capacity was estimated at 87,500 tons (79,000 Mg) in 1993 (SRI International, 1993).
5.2.2 Naphthalene Sulfonates Production
Process Description
The second largest end-use of naphthalene is the manufacture of naphthalene
sulfonates. Naphthalene sulfonates are generally manufactured by addition of sulfuric acid to
naphthalene over heat. Naphthalene sulfonates can be further modified chemically to produce a
large mixture of compounds and derivatives. Historically, naphthalene sulfonates were used
mainly as synthetic tanning agents, which are used for both vegetable- and chrome-tanned
leather. The use of naphthalene sulfonates as tanning agents has declined along with the decline
in the domestic leather industry, but increasing use as surface active agents (better known as
surfactants) has replaced that demand (U.S. EPA, 1986).
Surfactants are used as wetting agents and dispersants in paints, dyes, pigments,
coatings, polymerization emulsifiers, and concrete additives, as well as in a variety of pesticides
and cleaner formulations. The application of naphthalene sulfonate compounds, primarily
2-naphthaIenesuIfonic acid, its alkyl derivatives, and their salts, as surfactants is expected to
grow although naphthalene derivatives represent a small portion (less than 0.5 percent) of the
total production of surface active agents. The use of these products as concrete additives
(i.e., plasticizers) has also increased. Naphthalene sulfonates can increase the flow of concrete
without decreasing its strength.
5-13
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Emission Factors
As with phthalic anhydride, little or no information is available on naphthalene
emission sources from the production of naphthalene sulfonates. Therefore, naphthalene
emissions were estimated in the 1986 assessment using the estimate that 0.034 percent of total
naphthalene consumed during production each year is emitted to the air. Thus, it was estimated
from naphthalene consumption data that the production of naphthalene sulfonates accounted for
8.1 tons (7.4 Mg) of naphthalene emissions in 1986 (U.S. EPA, 1986).
Source Locations
There are several different naphthalene sulfonate derivatives produced by a
number of companies. It is not always possible to distinguish whether all of a naphthalene
sulfonate compound produced at a given facility is intended for use as a synthetic tanning agent
or surfactant or some other miscellaneous use. Hence, the location of all producers cannot be
identified. The major producers of synthetic tanning agents and surfactants from naphthalene on
which the 1986 assessment was based included the companies listed in Table 5-3.
5.2.3 Carbamate Insecticide Production
Process Description
The third largest use of naphthalene is as a raw material for the manufacture of
carbamate insecticides, of which carbaryl (Arylam® or better known as Sevin®) is the most
important. Carbaryl is used as a substitute for DDT and other chlorinated compounds that have
become environmentally unacceptable. It is registered for use on about 70 crops and is used
chiefly in the southern and western United States.
Crude or semi-refined coal tar or petroleum naphthalene can be used for carbaryl
manufacture. Production involves the following steps: (1) hydrogenation of naphthalene to
produce 1,2,3,4-tetrahydronaphthalene, (2) oxidation of this compound to produce 1-naphthol,
5-14
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TABLE 5-3. MAJOR PRODUCERS OF NAPHTHALENE-BASED SYNTHETIC
TANNING AGENTS AND SURFACE ACTIVE AGENTS
Naphthalene End-Use
Plant
Location
Synthetic Tanning Agents
Morflex, Inc.
Diamond Shamrock
Georgia-Pacific
Rohm and Haas
Greensboro, NC
Carlstadt, NJ
Cedartown, GA
Bellingham, WA
Philadelphia, PA
Surface Active Agents
American Cyanamid
Ciba-Geigy
DeSoto, Inc.
Diamond Shamrock
Emkay Chemicals
Morflex, Inc.
Georgia-Pacific
Marietta, OH
Linden, NJ
Toms River, NJ
Fort Worth, TX
Carlstadt, NJ
Cedartown, GA
Elizabeth, NJ
Greensboro, NC
Bellingham, WA
Source: U.S. EPA, 1986.
5-15
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and (3) reaction of 1-naphthol with methyl isocyanate to produce 1-naphthyl-n-methyl carbamate
(carbaryl). Intermediate products of this process, 1,2,3,4-tetrahydronaphthalene and 1-naphthol,
are also used as insecticides.
Emission Factors
Again, little information is available on naphthalene emission sources from the
production of carbamate insecticides. Therefore, naphthalene emissions were estimated in the
1986 assessment using emissions inventory data provided by the sole U.S. carbaryl producer.
The data indicate that the production of carbaryl accounted for 5.0 tons (4.6 Mg) of naphthalene
emissions in 1986. If specific information for the plant can be obtained, equipment leak
emission factors for the SOCMI, storage vessel emission factors from EPA's AP-42 document,
or the estimate that 0.034 percent of total naphthalene consumed during production each year is
emitted to the air could be used to check this estimate.
Source Locations
Rhone-Poulenc at Institute, West Virginia, is the only domestic producer of
carbaryl, having purchased the business from Union Carbide in 1987.
5.2.4 Moth Repellant Production
Process Description
The manufacture of moth repellant accounts for the fourth largest use of
naphthalene. The production of naphthalene-based moth repellant has decreased, however, due
to the availability of para-dichlorobenzene and the increased use of synthetic fibers. Moth
repellant is the only consumer product manufactured directly from naphthalene. The product is
manufactured as a solid flake, powder, or ball, and repackaged for shipment. All of the
naphthalene contained in moth repellant is emitted to the atmosphere.
5-16
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Emission Factors
It was assumed in the 1986 assessment that because production of moth repellant
only involved repackaging naphthalene in the solid form, no process, fugitive, or storage
emissions were expected. Hence, no emissions were estimated for this use of naphthalene.
However, if it is discovered that the manufacture does involve processing of naphthalene in the
liquid form, equipment leak emission factors for the SOCMI, storage vessel emission factors
from EPA's AP-42 document, or the estimate that 0.034 percent of total naphthalene consumed
during production each year is emitted to the air could be used to estimate emissions
(U.S. EPA, 1986).
Source Locations
Two producers of naphthalene-based moth repellant were identified in the 1986
assessment: Morflex, Inc. of Greensboro, North Carolina, and Kincaid Enterprises of Nitro,
West Virginia (U.S. EPA, 1986).
5.2.5 Miscellaneous Uses
Process Description
Approximately 3 percent of naphthalene consumption is used in the manufacture
of various organic chemicals and intermediates. There are numerous miscellaneous naphthalene
derivatives including the following:
• Alkylnaphthalenes;
• Chlorinated naphthalenes;
• Hydrogenated naphthalenes;
• Naphthalenecarboxylic acids;
5-17
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• Nitronaphthalenes;
• Naphthylamines;
• Naphthols; and
• Aminonaphthols.
These chemicals are produced in relatively small amounts and cannot be
separately quantified.
Emission Factors
As with naphthalene sulfonate compounds, there are several miscellaneous
naphthalene derivatives produced by a number of companies. Naphthalene emissions were again
estimated in the 1986 assessment from the naphthalene consumption by a few major endusers
using the estimated factor of 0.034 percent of total naphthalene consumed during production
each year is emitted to the air. It was estimated that the production of naphthalene sulfonates
accounted for 1.5 tons (1.4 Mg) of naphthalene emissions in 1986.
Source Locations
In 1986, the major producers of miscellaneous naphthalene chemicals on which
the 1986 assessment was based included the companies listed in Table 5-4.
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TABLE 5-4. MAJOR PRODUCERS OF MISCELLANEOUS
NAPHTHALENE-BASED CHEMICALS
Plant Location
Chemical Exchange Houston, TX
Ciba-Geigy Toms River, NJ
Koppers Company Follansbee, WV
RSA Corporation Ardsley, NY
Sigma Chemical Company St. Louis, MO
Union Carbide Ambler, PA
Uniroyal, Inc. Gastonia, NC
Source: U.S. EPA, 1986.
5-19
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SECTION 5.0 REFERENCES
Chemical Marketing Reporter. Naphthalene. December 13,1993.
Code of Federal Regulations. 40 CFR Part 60, Subpart Kb, "Standards of Performance for
Volatile Organic Liquid Storage Vessels (including Petroleum Liquid Storage Vessels) for which
Construction, Reconstruction, or Modification Commenced after July 23, 1984."
Code of Federal Regulations. 40 CFR Part 61, Subpart L, "National Emission Standard for
Benzene Emissions from Coke Byproduct Recovery Plants."
Federal Register. Assessment of Naphthalene As a Potentially Toxic Air Pollutant. 53 FR 9139.
Government Printing Office, Washington, D.C. March 21, 1988.
Mannsville Chemical Products Corporation. Naphthalene. "Chemical Products Synopsis."
Asbury Park, New Jersey. March 1993.
SRI International. 1993 Directory of Chemical Producers. Menlo Park, California. 1993.
U.S. Environmental Protection Agency. Summary of Emissions Associated with Sources of
Naphthalene. Emission Standards Division, Office of Air Quality Planning and Standards,
Research Triangle Park, North Carolina. EPA-450/3-88-003. October 30,1986.
U.S. Environmental Protection Agency. Benzene Emissions from Coke Byproduct Recovery
Plants - Background Information Document for Proposed Standards. Office of Air Quality
Planning and Standards, Research Triangle Park, North Carolina. EPA-450/3-83-016a.
May 1984.
U.S. Environmental Protection Agency. Environmental Assessment of Coke Byproduct
Recovery Plants. Industrial Environmental Research Laboratory, Research Triangle Park,
North Carolina. EPA-600/2-79-016. January 1979.
5-20
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SECTION 6.0
SOURCE TEST PROCEDURES
Several sampling and analytical techniques have been employed for the
quantification of POM. The selection of sampling and analytical techniques is driven by the
nature of the emissions source, the quantity of POM present, and the specific POM compounds
of interest. The following methods are applicable for measuring POM emissions from stationary
sources, ambient air, and vehicle exhaust:
EPA Method 0010: Modified Method 5 Sampling Train;
EPA Method 8270: Gas Chromatography/Mass Spectrometry (GC/MS)
for Semivolatile Organics, Capillary Column Technique;
• EPA Method 8310: Polynuclear Aromatic Hydrocarbons by High
Performance Liquid Chromatography (HPLC);
• EPA Method TO-13: Determination of Polynuclear Aromatic
Hydrocarbons (PAHs) in Ambient Air Using High Volume Sampling with
GC/MS and HPLC; and
• EPA Exhaust Gas Sampling System, Federal Test Procedure (FTP).
6.1 EPA METHOD 0010
EPA Method 0010 (Modified Method 5 Sampling Train [MM5]) is used to
determine the destruction and removal efficiency of semi-volatile principal organic hazardous
constituents (POHCs) from incineration systems and other stationary sources. This method may
be used for determining POM emissions.
The MM5 sampling train is an adaptation of the EPA Method 5 train used in
measuring paniculate emissions (U.S. EPA, 1986; U.S. EPA, 1991). The modifications are the
addition of a condenser and a sorbent module between the filter and the impingers. The
condenser cools the gas stream leaving the filter and conditions the streams prior to entering the
sorbent module.
6-1
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Gaseous and particulate pollutants are withdrawn isokinetically from an emissions
source and collected in a multicomponent sampling train. Figure 6.1-1 presents a schematic of
the sampling system. Principal components of the train include a high-efficiency glass- or
quartz-fiber filter and a packed bed of porous polymeric adsorbent resin (typically XAD-2® for
POM emissions). The filter is used to collect organic-laden particulate materials and the porous
polymeric resin to adsorb semivolatile organic species (compounds with a boiling point above
100°C). It should be noted that the XAD-2® must be carefully cleaned to avoid contamination
from naphthalene, a XAD-2® artifact. In addition, the sorbent module should be wrapped in
aluminum foil to protect it from light, which can adversely affect analysis.
The MM5 train is designed to operate at flow rates of approximately 0.015 dry
standard cubic meter per minute (dscmm) (0.5 dscfm) over a 4-hour sampling period. Sample
volumes of 3 dscm (100 dscf) are typical, although the volume that is sampled will vary
according to the analyte. Because method detection limits are a function of volume sampled, this
will also vary.
The entire sorbent module with filter is typically extracted with methylene
chloride. The extract must not contain any moisture or methanol, or the analyses will be
compromised. The extract is concentrated to 5 milliliters (mL) (a final volume of 5 mL is used
to avoid loss of volatile compounds) and this final extract volume represents the entire volume of
gas sampled. It should also be noted that when extracting the rinse solutions from the impingers,
sufficient water must be added to separate the methanol from the methylene chloride.
After sampling and extraction, comprehensive chemical analyses using a variety
of applicable analytical methodologies are conducted to determine the identity and concentration
of the organic materials.
6-2
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TMnpmtum Senior
Prob»
R«vwM-TyiM Pilot Tube
DiyGM Meter Air Tight Pump
Figure 6.1 -1. Modified Method 5 Sampling Train (EPA Method 0010)
Check V«t»
Vacuum Una
Source: U.S. EPA, 1986.
-------
A major advantage of the MM5 train is that the method provides both a
quantitative sample for POM analysis and a determination of paniculate loading (front-half
filterable particulates) comparable to EPA Method 5. A disadvantage is that long sampling
periods are required to collect enough sample to support chemical analysis.
When GC/MS is used as the analytical technique, compounds that coelute
chromatographically can frequently be deconvoluted if their mass spectra are different. Using
two or more ions per compound in quantitative analysis can overcome interference at one mass;
however, if the concentration of the compound of interest is sufficient to saturate the detector at a
given mass, an alternative mass may not be selected. In this case, the extract must be diluted to
bring the concentration of the compound of interest into the calibration range in order to obtain
accurate quantitative analysis (U.S. EPA, 1991).
6.2 EPA METHOD 8270
EPA Method 8270 is a GC/MS method used to determine the concentration of
semivolatile organic compounds in extracts prepared from all types of solid waste matrices, soils,
and groundwater (U.S. EPA, 1986; U.S. EPA, 1991). It is also applicable to an extract (such as
POM) from sorbent media in conjunction with Method 0010. The practical quantitation limit for
Method 8270 is approximately 50 ug/mL of extract. Direct injection of a sample may be used in
limited applications.
Method 8270 can be used to quantify most neutral, acidic, and basic organic
compounds that are soluble in methylene chloride and capable of being eluted without
derivatization as sharp peaks from a gas chromatographic fused-silica capillary column coated
with a slightly polar silicone. POM compounds are within the boiling point range and may be
determined using this methodology.
EPA Method 8270 describes conditions for capillary column GC/MS to allow for
the separation of semivolatile compounds. Sample extraction, purification, and
6-4
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concentration techniques are addressed in other methods. For example, EPA Methods 3510,
3520, 3540, 3550, and 3580 may be applicable to POM sample preparation. (U.S. EPA, 1991)
The following purification methods may be used prior to GC/MS analysis: EPA Methods 3611,
3630, and 3640 (U.S. EPA, 1991).
Raw GC/MS data from all blanks, samples, and spikes must be evaluated for
interferences. If an interference results from the preparation and/or cleanup of samples,
corrective action can be taken to eliminate the problem. If the problem is a very high sample
background of alkyl or aromatic hydrocarbons, very little can be done to resolve the problem
other than dilution of the samples, which raises the detection limit. If chromatographic coelution
occurs, deconvolution of the coeluting components by mass spectrometric techniques will be
effective if the compounds are not chemically related and their mass spectra can be resolved. If
isomers coelute and their mass spectra are similar, the coelution cannot be resolved (U.S. EPA,
1991).
Contamination by carryover can occur whenever high-level and low-level samples
are analyzed sequentially. To reduce carryover, the sample syringe must be rinsed carefully with
solvent between sample injections. The chromatographic column should be allowed to remain at
a high temperature until all late-eluting components have eluted from the column in order to
avoid chromatographic carryover problems. Whenever an unusually concentrated sample is
encountered, it should be followed by the analysis of clean solvent to check for cross-
contamination. If contamination is observed, the injections of solvent should be repeated until
the contamination ib no longer observed before another sample injection is performed (U.S. EPA,
1991).
6.3 EPA METHOD 8310
EPA Method 8310 is used to determine the concentration of certain PAHs in
groundwater and wastes at parts-per-billion levels (U.S. EPA, 1986; U.S. EPA, 1991). By
extension, the methodology should be applicable to material extracted from a solid sorbent
6-5
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module of a sampling train from EPA Method 0010, which is used to sample gaseous emissions
from a stationary source.
Extension of the methodology to PAHs containing functional groups should be
possible, depending upon the ability to adjust analytical conditions and the availability of
standards for the compounds of interest.
Prior to using Method 8310, appropriate sample extraction methods must be used.
A 5- to 25-uL aliquot of extract is injected into an HPLC, and compounds in the effluent are
detected by ultraviolet (UV) and fluorescence detectors. If interferences prevent proper detection
of the analytes of interest, the method may also be performed on extracts that have undergone
purification using silica gel column cleanup (EPA Method 3630).
Use of Method 8310 presupposes a high expectation of finding the specific
compounds of interest. To screen samples for any or all of the method target compounds,
independent protocols for the verification of identity must be developed. One method that can be
used to certify identity is GC/MS.
Method detection limits are compound-dependent, ranging from 0.4 ug/L for
indeno(l,2,3-cd)pyrene in groundwater to 230,000 ug/L for acenaphthylene in non-water
miscible waste. Detection limits for PAHs in gaseous emissions have not been determined
directly. This methodology has not been directly and specifically applied to the determination of
POM other than the PAHs specifically listed in the methodology. A quantitative analysis of
other PAHs and functionalized PAHs will require adjustment of analytical conditions and the use
of appropriate standards. An additional method such as GC/MS, if applicable, may be required
to identify additional compounds (U.S. EPA, 1991).
If coelution of compounds is encountered in samples taken from gaseous
emissions of stationary sources, Method 8310 may not be applicable unless analytical conditions
can be adjusted to achieve chromatographic resolution.
6-6
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The sensitivity of the method usually depends on the level of interferences rather
than instrumental limitations. The limits of detection mentioned earlier for the liquid
chromatographic approach represent sensitivities that can be achieved in the absence of
interferences. When interferences are present, the level of sensitivity will be lower, if analysis is
possible at all (U.S. EPA, 1991).
Solvents, reagents, glassware, and other sample processing hardware may yield
discrete artifacts and/or elevated baselines, causing misinterpretation of the chromatograms. All
of these materials must be demonstrated to be free from interferences under the conditions of the
analysis by analyzing method blanks. Specific selection of reagents and purification of solvents
by distillation in all-glass systems may be required.
Interferences coextracted from the samples will vary considerably from source to
source. Although a general cleanup technique is provided as part of Method 8310, individual
samples may require additional cleanup approaches to achieve the desired sensitivity.
The chromatography conditions described in Method 8310 allow for a unique
resolution of the specific PAH compounds covered by this method. Other PAH compounds, in
addition to matrix artifacts, may interfere.
6.4 EPA METHOD TO-13
Method TO-13 describes sampling and analytical techniques used to determine
benzo(a)pyrene and other PAHs in ambient air. Nitro-PAHs are not included with this method.
In Method TO-13, air is drawn through a filter and adsorbent cartridge containing XAD-2® or
polyurethane foam (PUF). As with EPA Method 0010, the XAD-2® resin must be carefully
cleaned to avoid contamination from naphthalene, and the adsorbents should be protected from
light during sampling and storage. In addition, the quality of PUF will vary markedly from lot to
lot, so every effort should be made to obtain PUF from the same production lot for sampling at a
single site.
6-7
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The filters and adsorbents are extracted, and the extract is subjected to cleanup
with silica gel column chromatography. The sample is further concentrated and analyzed by
either gas chromatography equipped with flame ionization detector or a mass spectrometer, or
HPLC.
The relatively low level of PAHs in the environment requires use of high-volume
(approximately 6.7 cfm) sampling techniques to acquire sufficient sample for analysis. However,
the volatility of certain PAHs prevents efficient collection on filter media alone. Consequently,
this method utilizes both a filter and a backup adsorbent cartridge, which provide for efficient
collection of most PAHs (U.S. EPA, 1988).
Method interferences may be caused by contaminants in solvents, reagents,
glassware, and sampling hardware. Matrix interferences may be caused by contaminants that are
coextracted with the sample. Heat, ozone, nitrogen dioxide, and UV light may cause sample
degradation.
Detection limits for GC and HPLC methods range from 1 ng to 10 pg, which
represents detection of PAHs in filtered air at levels below 100 pg/m3. To obtain this detection
limit, at least 100 m3 of air must be sampled (U.S. EPA, 1988).
6.5 FEDERAL TEST PROCEDURE (FTP)
The most widely-used test procedure for sampling emissions from vehicle exhaust
is the FTP, which was initially developed in 1974 (40 CFR 86, Subpart B; Blackley Telecon,
1994a and 1994b). The FTP uses the Urban Dynamometer Driving Schedule (UDDS), which is
1,372 seconds in duration. An automobile is placed on a chassis dynamometer, where it is run
according to the following schedule: 505 seconds of cold-start; 867 seconds of hot transient; and
505 seconds of hot-start. (Definitions of the above terms can be found in the FTP description in
the 40 CFR, Section 86, Subpart B). The vehicle exhaust is collected in three separate teflon
bags associated with backup filters/adsorbents for each of the three testing stages.
6-8
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The most widely used method for transporting vehicle exhaust from the vehicle to
the bags is a dilution tube sampling arrangement identical to the system used for measuring
criteria pollutants from mobile sources (40 CFR 86, Subpart B; Smith, 1988). Dilution
techniques are used for sampling auto exhaust because, in theory, dilution helps simulate the
conditions under which exhaust gases condense and react in the atmosphere. Figure 6.5-1 shows
a diagram of a vehicle exhaust sampling system (Lee and Schuetzle, 1985). Vehicle exhausts are
introduced at an orifice where the gases are cooled and mixed with a supply of filtered dilution
air. The diluted exhaust stream flows at a measured velocity through the dilution tube and is
sampled isokinetically.
The major advantage in using a dilution tube approach is that exhaust gases are
allowed to react and condense onto particle surfaces prior to sample collection, providing a truer
composition of exhaust emissions as they occur in the atmosphere. Another advantage is that the
dilution tube configuration allows simultaneous monitoring of hydrocarbons, CO, CO2, and NOX.
Back-up sampling techniques, such as filtration/adsorption (e.g., XAD-2®, Chromsorb 102, or
Tenax®), are generally recommended for collection of both particulate- and gas-phase emissions
(Blackley Telecon, 1994b). This is a particularly true for POM, which is often found in
particulate form in vehicle exhaust.
After the exhaust samples are collected, extraction using EPA Method 3540 is
recommended, followed by analysis using EPA Method 8270, described earlier.
6-9
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o\
Ambient Air Inlet
o
Vehicle
Exhaust
Inlet
SYMBOL
LEGEND
Row Control
Valve
Paniculate
Rlter
Pump
Flowmeter
T Temperature
V Sensor
To
Dilution Air
Sample Bag
Heat
Exchanger
\ Preheater
A A A
Coolant
To
Exhaust Sample Bag
Figure 6.5-1. Vehicle Exhaust Gas Sampling System
• To Methanol Sample Collection
• To Formaldehyde Sample Collection
Positive Displacement Pump
Manometer
Revolution
Counter
Pickup
Discharge
2
UJ
Source: Source: Lee, 1985.
-------
SECTION 6.0 REFERENCES
C. Blackley, Radian Corporation, telephone communication with R. Zweidinger, U.S.
Environmental Protection Agency. May 10, 1994. 1994a.
C. Blackley, Radian Corporation, telephone communication with P. Gabele, U.S. Environmental
Protection Agency. May 10, 1994. 1994b.
Code of Federal Regulations, 40 CFR Part 86, Subpart B. "Emission Regulations for 1977 and
Later Model Year New Light-Duty Vehicles and New Light-Duty Trucks; Test Procedures."
December 10, 1993.
Lee, F.S., and D. Schuetzle. "Sampling, Extraction, and Analysis of Polycyclic Aromatic
Hydrocarbons from Internal Combustion Engines." In: Handbook of Polvcyclic Aromatic
Hydrocarbons. A. Bjorseth, ed. Marcel Dekker, Inc., New York. p. 30. 1985.
Smith, Lawrence R. Butadiene Measurement Technology. EPA-460/3-88-005. August 1988.
U.S. Environmental Protection Agency. Screening Methods for Development of Air Toxics
Emission Factors. Research Triangle Park, North Carolina. EPA-450/4-91-021.
September 1991.
U.S. Environmental Protection Agency. Compendium of Methods for the Determination of
Toxic Organic Compounds in Ambient Air. Atmospheric Research and Exposure Assessment
Laboratory, Research Triangle Park, North Carolina. EPA-600/4-89-017. June 1988.
U.S. Environmental Protection Agency. Test Methods for Evaluating Solid Waste. Office of
Solid Waste and Emergency Response, Washington, DC. Third Edition, Report No. SW-846.
November 1986.
6-11
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APPENDIX A
SUMMARY OF 7-PAH AND 16-PAH EMISSION FACTORS
-------
Table A-l provides a summary of 7-PAH and 16-PAH emission factors for source
categories for which the EPA has developed national emission estimates to meet the
requirements of Section 112 (c)(6) of the CAAA. Section 112 (c)(6) requires the EPA to look at
seven specific pollutants, including POM, in order to develop a national strategy to control these
pollutants. The source categories listed in Table A-l do not represent all the potential POM
source categories discussed earlier in this document. The EPA did not always have activity
levels to match to the available emission factors for every source category, so Table A-l only
contains those categories for which an activity level was available to calculate national
emissions.
The 16-PAH factors represent the sum of the emission factors for the following
individual PAHs, where available, for each source category:
Naphthalene Benzo(ghi)perylene
Acenaphthene Benz(a)anthracene*
Acenaphthylene Chrysene*
Fluorene Benzo(b)fluoranthene*
Phenanthrene Benzo(k)fluoranthene*
Anthracene Benzo(a)pyrene*
Fluoranthene Dibenz(a,h)anthracene
Pyrene Indeno(l,2,3-cd)pyrene*
The pollutants with asterisks (*) correspond to the subset of seven PAHs for which emission
factors were summed, where available, for each source category to obtain the
7-PAH emission factor.
For each source category there was not always a complete set of the seven or
sixteen PAH emission factors in order to compile the 7-PAH and 16-PAH factors, respectively.
Therefore, the 7-PAH and 16-PAH emissions are not directly comparable across all source
categories.
A-l
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For most of the source categories listed in Table A-l, the 16-PAH and 7-PAH
emission factors were derived from the individual POM compound emission factors presented in
the emission factor tables in this document. The exceptions are the "Ferroalloy Manufacturing"
and the "Onroad Vehicles" source categories; the 16-PAH and 7-PAH emission factors presented
in Table A-l for these source categories were developed by EPA specifically for the purpose of
the national emission inventory effort in support of the Section 112(c)(6) study and were not
derived from the emission factor tables contained in this document. The 16-PAH and 7-PAH
emission factors for these categories were developed by EPA from alternative sources for which
background information on the individual POM compounds included in the 16-PAH and 7-PAH
subsets was not available to present in a consistent format with this document (i.e., individual
POM species factors were not available). The reader is referred to the documentation for the
112(c)(6) inventory effort for details on how the 16-PAH and 7-PAH factors were developed for
each source category, including the "Ferroalloy Manufacturing" and "Onroad Vehicles" sources
(U.S. EPA, 1998).
When using the emission factors in Table A-1, the user should keep in mind that
these were developed to be representative of nationwide activity and do not, in most cases,
represent the particularities of a specific site. If modeling specific site conditions, or if the focus
is on individual POM compounds, the user should refer to the emission factor tables for the
particular source category where available in previous sections of this document.
A-2
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TABLE A-l. SUMMARY OF EMISSION FACTORS FOR 7-PAHa AND
16-PAHb SUBSETS BY SOURCE CATEGORY
Source Category
7-PAH
Emission Factor0
16-PAH
Emission Factor"1
STATIONARY EXTERNAL COMBUSTION
Residential Heating
Residential Wood Combustion
Conventional Woodstoves
Catalytic/Noncatalytic Stoves
Fireplaces
Residential Natural Gas Combustion
Residential Distillate Oil Combustion
Residential Coal Combustion (bituminous
and lignite)
Residential Coal Combustion (anthracite)
0.044 Ib/ton wood burned
0.048 Ib/ton wood burned
0.007 Ib/ton wood burned
0.0373 1W1E+12 Btu of heat input
5.63E-04 lb/1,000 gal of fuel consumed
0.0335 Ib/ton of coal consumed
1.41E-04 Ib/ton of coal consumed
0.718 Ib/ton wood burned
0.627 Ib/ton wood burned
0.037 Ib/ton wood burned
2.37 lb/lE+12 Btu of heat input
6.97E-03 lb/1,000 gal of fuel consumed
0.108 Ib/ton of coal consumed
6.18E-04 Ib/ton of coal consumed
Utility, Industrial, and Commercial Boilers
Industrial Wood/Wood Residue Combustion
Industrial Natural Gas Combustion
Industrial Coal Consumption
Industrial Residual Oil Combustion
Industrial Distillate Oil Combustion
Industrial Waste Oil Combustion
Commercial Wood/Wood Residue
Combustion
Commercial Natural Gas Combustion
Commercial Coal Combustion (bituminous
and lignite)
Commercial Coal Combustion (anthracite)
Commercial Residual Oil Combu:non
Commercial Distillate Oil Combustion
5.90E-05 Ib/ton of wood burned
ND
5.36E-05 Ib/ton of coal consumed
1.60E-07 Ib/MMBtu of heat input
5.96E-09 Ib/MMBtu of heat input
4.53E-03 lb/1,000 gallons of
waste oil consumed
7.43E-05 Ib/MMBtu of heat input
ND
0.0200 Ib/ton of coal consumed
ND
1.60E-07 Ib/MMBtu of heat input
5.96E-09 Ib/MMBtu of heat input
3.36E-03 Ib/ton of wood burned
5.56E-06 Ib/MMCF of natural gas consumed
2.72E-03 Ib/ton of coal consumed
2.15E-04 Ib/MMBtu of heat input
5.00E-05 Ib/MMBtu of heat input
0.0265 lb/1,000 gallons of
waste oil consumed
2.63E-03 Ib/MMBtu of heat input
2.54E-05 Ib/MMCF of natural gas consumed
0.0771 Ib/ton of coal consumed
0.137 Ib/ton of coal consumed
2 14E-04 Ib/MMBtu of heat input
5.00E-05 Ib/MMBtu of heat input
STATIONARY INTERNAL COMBUSTION
Industrial 1C Engines
Industrial 1C Engines - Diesel
Industrial 1C Engines - Natural Gas
3.36E-06 Ib/MMBtu of heat input
2.75E-03 Ib/MMCF of natural gas consumed
1.89E-04 Ib/MMBtu of heat input
0.1271b/MMCP of natural gas consumed
A-3
(continued)
-------
TABLE A-1. (Continued)
Source Category
7-PAH
Emission Factor0
16-PAH
Emission Factor11
Turbines
Turbines - Diesel
Turbines - Natural Gas
ND
ND
1.03E-07 Ib/MMBtu of heat input
4.90E-05 Ib/MMBm of heat input
WASTE INCINERATION
Municipal Waste Incineration
Sewage Sludge Incineration
Medical Waste Incineration
Hazardous Waste Incineration
Drum and Barrel Reclamation
Scrap Tire Incineration
Landfill Flares
ND
1.822E-05 Ib/ton of sludge incinerated
ND
2.91E-05 Ib/ton of hazardous waste
incinerated
5.53E-07 lb/1,000 barrels reclaimed
1.68E-03 lb/lE+06 tires incinerated
3.08E-08 Ib/MMBtu of heat input
6.07E-06 Ib/ton of waste incinerated
3.44E-03 Ib/ton of sludge incinerated
9.22E-04 Ib/ton of waste incinerated
2.44E-04 Ib/ton of hazardous waste
incinerated
3.56E-05 lb/1,000 barrels reclaimed
0.40 lb/lE+06 tires incinerated
1.30E-05 Ib/MMBtu of heat input
METALS INDUSTRY
Primary Aluminum Production
Horizontal Stud Soderberg Cells
Vertical Soderberg Cells
Vertical Pre-bake Cells
Casting Operations
Paste Production
Anode Bake Furnaces
Sintering in the Iron and Steel Foundries
Ferroalloy Manufacturing5
Wood-fired Open EAFs
Coal-fired Open EAFs
Coke-fired Open EAFs
Iron Foundries
Secondary Lead Smelting - Blast Furnaces
Secondary Lead Smelting - Rotary and
Blast/Reverb Furnaces
0.058 Ib/ton aluminum produced
0.12 Ib/ton aluminum produced
0.0013 Ib/ton aluminum produced
3.64E-04 Ib/ton aluminum produced
0.0019 Ib/ton aluminum produced
0.05 Ib/ton aluminum produced
ND
8.24E-04 Ib/ton wood consumed
2.32E-03 Ib/ton coal consumed
2.32E-04 Ib/ton coke consumed
2.07E-05 Ib/ton of metal produced
ND
3.7E-05 Ib/ton of lead produced
0.59 Ib/ton aluminum produced
0.49 Ib/ton aluminum produced
0.0073 Ib/ton aluminum produced
1.30E-02 Ib/ton aluminum produced
0.015 Ib/ton aluminum produced
0.135 Ib/ton aluminum produced
ND
1.75E-03 Ib/ton wood consumed
5.04E-03 Ib/ton coal consumed
5.03E-04 Ib/ton coke consumed
6.21E-05 Ib/ton of metal produced
0.0199 Ib/ton of lead produced
5. IE-OS Ib/ton of lead produced
PETROLEUM REFINING
Catalytic Cracking
1.66E-05 lb/barrel of oil charged
3.16E-04 lb/barrel of oil charged
ASPHALT PRODUCTION
Asphalt Roofing Production
Asphalt Hot-mix Production
1 . 1E-04 Ib/ton of asphalt
roofing produced
3.90E-07 Ib/ton of hot-mix asphalt Droduced
2.86E-03 Ib/ton of asphalt
roofing produced
1 .82E-04 Ib/ton of hot-mix asphalt produced
A-4
(continued)
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TABLEA-1. (Continued)
Source Category
7-PAH
Emission Factor0
16-PAH
Emission Factor"1
COKE PRODUCTION
Coke Ovens: Charging, Topside, and Door
Leaks
Coke Ovens: Pushing, Quenching, and
Battery Stacks
3.72E-03 Ib/ton of coal charged
3.09E-03 Ib/ton of coal charged
2.79E-02 Ib/ton of coal charged
0.053 Ib/ton of coal charged
PORTLAND CEMENT
MANUFACTURING
Non-hazardous Waste Kilns
Hazardous Waste Kilns
8.21E-05 Ib/ton clinker produced
2.52E-04 Ib/ton clinker produced
1.51E-03 Ib/ton clinker produced
1.53E-03 Ib/ton clinker produced
PULP AND PAPER INDUSTRY
Kraft Recovery Furnaces
Lime Kilns
Sulfite Recovery Furnaces
1.23E-04 Ib/air-dry ton of pulp produced
3.3E-06 Ib/MMBtu of heat input
ND
0.0213 Ib/air-dry ton of pulp produced
2.46E-03 Ib/MMBtu of heat input
4.30E-03 Ib/air-dry ton of pulp produced
OPEN BURNING
Wildfires and Prescribed Burning
Open Burning of Scrap Tires
0.020 Ib/ton of biomass burned
1.400 lb/1,000 tons of tire burned
0.053 Ib/ton of biomass burned
7,850 lb/1,000 tons of tire burned
MOBILE SOURCES
Onroad Vehicles'
Aircraft
Locomotives
Marine Vessels
Non-road Vehicles and Equipment
14.52 Mg/vehicle miles of travel
1.09E-05 Ib/LTO
ND
ND
ND
32.08 Mg/vehicle miles of travel
3.06E-04 Ib/LTO
ND
ND
ND
MISCELLANEOUS SOURCES
Carbon Black Manufacturing
Wood Treatment/Wood Preserving
Cigarette Smoke
Crematories
Gasoline Distribution
Carbon Fiber Manufacturing
5.25E-04 Ib/ton of carbon black produced
ND
2.08E-09 Ib/cigarette consumed
7.07E-11 Ib/body cremated
ND
NA
5.04E-03 Ib/ton of carbon black produced
1.94E-03 Ib/ft3 of wood treated
1.38E-08 Ib/cigarette consumed
4.16E-08 Ib/body cremated
NA
NA
NAPHTHALENE PRODUCTION AND USE
Naphthalene Production
Phthalic Anhydride Production
Carbamate Insecticides Production
ND
ND
ND
0.523 Ib/ton of naphthalene produced
0.0024 Ib/ton of coke produced
0.34 lb/1, 000 Ib naphthalene consumed
0.34 lb/1 ,000 Ib naphthalene consumed
A-5
(continued)
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TABLE A-1. (Continued)
7-PAH 16-PAH
Source Category Emission Factor6 Emission Factor*1
Naphthalene Sulfonates Production ND 0.34 Ib/1,000 Ib naphthalene consumed
Miscellaneous Uses ND 0.34 lb/1,OOP Ib naphthalene consumed
a7-PAH subset includes benz(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(k)fluoranthene,
chrysene, dibenz(a,h)anthracene, and indeno(l,2,3-cd)pyrene.
b!6-PAH subset includes acenaphthene, acenaphthylene, anthracene, benz(a)anthracene, benzo(a)pyrene,
benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(ghi)perylene, chrysene, dibenz(a,h)anthracene,
fluoranthene, fluorene, indeno(l,2,3-cd)pyrene, naphthalene, phenanthrene, andpyrene.
CA117-PAH are not included in the 7-PAH factor for every source category; in some cases, there is not a
complete set of factors for all 7-PAH since the available test data did not report or sample for a specific
PAH compound(s). Refer to the documentation for the Section 116(c)(6) inventory development for a listing of the
specific compounds included in the 7-PAH emission factor for a particular source category (U.S. EPA, 1998).
dAll 16-PAH are not included in the 16-PAH factor for every source category; in some cases, there is not a
complete set of factors for all 16-PAH since the available test data did not report or sample for a specific
PAH compound(s). Refer to the documentation for the Section 116(c)(6) inventory development for a listing of the
specific compounds included in the 16-PAH emission factor for a particular source category (U.S. EPA, 1998).
eThe 7-PAH and 16-PAH emission factors presented here for this source category were not derived from the
individual POM emission factors presented earlier in this document for this source category. The factors presented
here were developed by EPA from alternative reference sources as part of the national inventory prepared to support
the Section 112(c)(6) strategy development. The reader should refer to the documentation for the Section 112(c)(6)
inventory development for more information on derivation of 7-PAH and 16-PAH emission factors for this source
(U.S. EPA, 1998).
A-6
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APPENDIX A REFERENCES
U.S. Environmental Protection Agency. 1990 Emissions Inventory of Section 1I2(c)(6) Pollutants:
Polvcvclic Organic Matter (POM). 2.3.7.8-Tetrachlorodibenzo-p-Dioxin (TCDDV
2.3.7.8-Tetrachlorodibenzofuran (TCDF). Polvchlorinated Biphenvl Compounds rPCBsl
Hexachlorobenzene. Mercury, and Alkylated Lead. Emission Factor and Inventory Group,
Research Triangle Park, North Carolina. Final Report. April, 1998.
A-7
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
2.
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
Locating and Estimating Air Emissions From
Sources of Polycyclic Organic Matter
5. REPORT
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
8. PERFORMING ORGANIZATION REPORT NO
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Eastern Research Group, Inc.
1600 Perimeter Park
Morrisville, North Carolina 27560
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-D7-0068
12. SPONSORING AGENCY NAME AND ADDRESS
Emission Monitoring and Analysis Division
OAR, OAQPS, EMAD, EFIG (MD-14)
Emission Factor and Inventory Group
Research Triangle Park, North Carolina 27711
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
EPA Project Officer:
Anne A. Pope
16. ABSTRACT
To assist groups interested in inventorying air emissions of various
potentially hazardous air pollutants, the EPA is preparing a series
of documents such as this to compile available information on sources
and emission of these substances. This document deals specifically
with polycyclic organic matter. Its intended audience includes
Federal, State and local air pollution personnel and others interested
in locating potential emitters of polycyclic organic matter and in
making estimates of air emissions therefrom.
This document presents information on (1) the types of sources that
may emit polycyclic organic matter, (2) process variations and release
points that may be emitted within these sources, and (3) available
emissions information indicating the potential for polycyclic organic
matter releases into the air from each operation.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS C. COS AT I Field/Group
Polycyclic organic matter (POM)
Polyaromatic hydrocarbon compounds
Air Emissions Sources
Locating Air Emissions Sources
Hazardous air pollutants
PAH)
18. DISTRIBUTION STATEMENT
Unlimited
19. SECURITY CLASS (ThisReport)
21. NO. Of PAGES
20. SECURITY CLASS (Thlspagel
22. PRICE
EPA f»rm 2220-1 («•». 4-77) PMCVIOUS COITION i* oetouerE
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