&EPA
United States
Environmental Protection
Agency
Office of Air Quality
Planning and Standards
Research Triangle Park NC 27711
EPA-453/R-93-025
June 1993
Air
AIR EMISSIONS AND CONTROL
TECHNOLOGY FOR LEATHER
TANNING AND FINISHING
OPERATIONS
control
technology center
-------
•o
K.
EPA-453/R-93-025
AIR EMISSIONS AND CONTROL TECHNOLOGY FOR
LEATHER TANNING AND FINISHING OPERATIONS
CONTROL TECHNOLOGY CENTER
SPONSORED BY:
Emissions Standards Division
Office of Air Quality Planning and Standards
U. S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
Air and Energy Engineering Research Laboratory
Office of Research and Development
U. S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
June 1993
U.S. Environ'---: •' iV^-tion Agency
Region 5, Li;,,,.... -12J)
77 West Jackson ;:.,j;evard, 12th Floor
Chicago, IL 60604-3590
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EPA-453/R-93-025
June 1993
AIR EMISSIONS AND CONTROL TECHNOLOGY FOR
LEATHER TANNING AND FINISHING OPERATIONS
Prepared by:
Barry F. Mitsch
Reese H. Howie
Samuel C. McClintock
Alpha-Gamma Technologies, Inc.
900 Ridgefield Drive, Suite 350
Raleigh, North Carolina 27609
Under Subcontract to:
Radian Corporation
3200 E. Chapel Hill Road/Nelson Highway
Research Triangle Park, North Carolina 27709
EPA Contract No. 68-01-0117
Work Assignment No. 79
Project Officer
Iliam Rosario
Emission Standards Division
U. S. Environmental Protection Agency
Reserach Triangle Park, North Carolina 27711
Prepared for:
Control Technology Center
U. S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
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Acknowledgement
This document was prepared for the EPA's Control Technology Center (CTC) by
Alpha-Gamma Technologies, Inc. under subcontract to Radian Corporation. The
Alpha-Gamma project team included Barry F. Mitsch, Reese H. Howie, and Samuel C.
McClintock. The EPA Work Assignment Manager was Iliam Rosario.
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PREFACE
The purpose of this document is to provide information to State and local
agencies for use in assessing appropriate measures to control volatile organic
compound (VOC) emissions from leather tanning and finishing facilities. Another
objective of the report is to evaluate leather tanning and finishing processes and
determine their potential to emit VOC's and hazardous air pollutants (HAP's) to the
atmosphere. This document is the product of a study sponsored by EPA's Control
Technology Center (CTC).
The CTC was established by EPA's Office of Research and Development (ORD)
and Office of Air Quality Planning and Standards (OAQPS) to provide technical
assistance to State and local air pollution control agencies. Three levels of assistance
are available through the CTC. First, the CTC maintains a hotline to provide telephone
assistance on matters relating to air pollution control technology. Second, engineering
assistance can be provided by the Center when appropriate. And finally, the CTC
provides technical assistance through publication of technical assistance documents,
development of personal computer software, and presentation of workshops on
control technology subjects.
This document represents the product of a CTC technical assistance effort.
The CTC became interested in pursuing this project as a result of numerous calls from
State and local agencies regarding control of VOC emission from leather tanning and
finishing facilities. This document was developed using information obtained from
available literature, information provided through Federal, State, and local air pollution
control agencies, and information obtained from the leather tanning and finishing
industry.
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TABLE OF CONTENTS
1.0 Introduction 1-1
1.1 Objectives of the Report 1-2
1.2 Overview of the Report 1-2
2.0 Industry Description 2-1
2.1 Characterization of the Industry .,.. 2-4
2.2 References 2-8
3.0 Leather Tanning and Finishing Processes 3-1
3.1 Wet operations 3-1
3.1.1 Soaking 3-3
3.1.2 Unhairing 3-3
3.1.3 Bating 3-5
3.1.4 Pickling 3-5
3.1.5 Tanning 3-5
3.1.6 Trimming and Siding 3-7
3.1.7 Splitting 3-7
3.1.8 Retanning 3-9
3.1.9 Coloring 3-9
3.1.10 Fatliquoring 3-9
3.2 Dry Operations 3-11
3.2.1 Drying 3-11
3.2.2 Conditioning 3-11
3.2.3 Staking and Milling 3-12
3.2.4 Buffing 3-12
3.3 Leather Finishing Operations 3-12
3.3.1 Coatings Used for Leather Finishing 3-12
3.3.2 Application Methods for Leather Finishing 3-19
3.3.2.1 Spray Systems 3-19
3.3.2.2 Roll Coating Machines 3-24
3.3.2.3 Flow Coating Machines 3-24
3.4 Additional Dry Operations 3-24
3.4 Waterproofing Operations 3-28
3.5 References 3-28
4.0 Characterization of Emissions 4-1
4.1 Sources of VOC and HAP Emissions 4-1
4.1.1 Leather Finishing Operations 4-1
4.1.2 Waterproofing Operations 4-4
4.1.3 Solvent Degreasing 4-6
4.1.4 Miscellaneous Fugitive Emissions 4-6
4.2 Factors Affecting VOC and HAP Emissions 4-7
4.3 Volatile Organic Compound Emissions 4-9
4.4 Hazardous Air Pollutant Emissions 4-9
4.5 References 4-15
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5.0 Emission Reduction and Control Techniques 5-1
5.1 Emission Control Techniques 5-1
5.1.1 Total Enclosure for Effective Capture of
VOC and Gaseous HAP 5-2
5.1.2 Control Devices 5-4
5.1.2.1 Thermal Incineration 5-4
5.1.2.2 Catalytic Incineration 5-9
5.1.2.3 Carbon Adsorption 5-11
5.1.3 Methods of Minimizing Control Costs - Volume Reduction 5-14
5.2 Emission Reduction Techniques 5-15
5.2.1 Use of Lower VOC and Water-Based Coatings 5-16
5.2.2 Emission Reductions from improved Transfer Efficiency . 5-18
5.2.2.1 High Efficiency Spray Guns 5-18
5.2.2.2 Optical Eye/Microprocessor Controls
on Spray Equipment 5-21
5.2.3 Housekeeping Operations 5-21
5.2.4 Degreasing Operations 5-21
5.2.5 Emission Reductions and Waterproofing Operations . . . 5-23
5.2.6 Radiation Curing of Top Coats 5-24
5.3 References 5-24
6.0 State and Local Regulations Affecting the Leather Tanning
and Finishing Industry 6-1
6.1 Regulations Limiting VOC Content of the Finishing Coatings 6-1
6.1.1 State of New Jersey 6-1
6.1.2 State of New York 6-3
6.1.3 State of Massachusetts 6-3
6.1.4 Monterey Bay Unified Air Pollution Control District 6-4
6.2 Regulations Limiting Emissions to Unit of Product Finished 6-4
6.3 State of Illinois 6-5
6.4 References 6-7
Appendices
Appendix A Emissions Data A-i
A.1 Introduction to Appendix A . A-ii
Appendix B Leather Tanning and Finishing Plants - Case Studies B-i
B.1 Introduction to Appendix B , B-ii
Plant A , B-1
Plant B B-5
Plant C B-10
Plant D B-13
PlantE B-17
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Appendix C State and Local Regulations Affecting Leather Tanning and
Finishing Facilities C-i
C.1 Introduction to Appendix C C-ii
State of New Jersey C-1
State of New York C-15
State of Wisconsin C-37
State of Massachusetts C-73
State of Illinois C-79
Monterey Bay Unified Air Pollution Control District C-85
Appendix D Leather Tanning and Finishing Facilities D-i
D.1 Introduction to Appendix D D ii
Appendix E Selected Contacts . E-i
E.1 Introduction to Appendix E E-ii
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LIST OF TABLES
Page
Table
2-1 Leather Tanning and Finishing Facilities in the United States 2-2
2-2 United States Production of Cattlehide Leather^ 2-6
2-3 Tanners' Stocks of all Cattlehide and Leathers 2-7
3-1 Comparison of Lacquer, Lacquer-emulsion and Water-based
Top Coat Systems 3-16
3-2 Generic Coating Formulations 3-17
3-3 Top Ten Products by Year and VOC Content 3-18
3-4 Surface Tensions of Various Solvents 3-20
4-1 Air Emission Compounds from Leather Facilities 4-2
4-2 Emissions from Leather Processing Monitored in the
United Kingdom in 1990 4-3
4-3 Representative Emission Factors for Leather Tanning and
Finishing Facilities 4-10
4-4 VOC Emissions from Representative Leather Tanning and Finishing
Facilities 4-11
4-5 Leather Tanning and Finishing Industry -- Major Sources of Hazardous Air
Pollutants 4-13
5-1 Design and Operating Parameters of Existing Regenerative
Thermal Incinerators 5-8
5-2 Comparison of Lacquer, Lacquer-emulsion and Water-based
Top Coat Systems 5-17
5-3 Transfer Efficiencies of Different Spray Techniques 5-19
5-5 Demonstration of Increased Transfer Efficiency with Optical Eyes 5-22
6-1 VOC Limitations in Existing State Regulations 6-2
6-2 State of Wisconsin - Emission Rates Identified by Finishing
Application Method 6-5
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LIST OF FIGURES
Page
Figure
3-1 Leather Tanning and Finishing Process - Flow Diagram 3-2
-•>
3-2 Mixing Drum used for Soaking and Unhairing 3-4
3-3 Drum Used for Bating, Pickling, and Tanning 3-6
3-4 Sections of a Cattle Hide Used for Leather Making 3-8
3-5 Splitting Machine 3-10
3-6 Staking Machine 3-13
3-7 Contact Angles of Leather Coatings 3-21
3-8 Rotary Spray Booth and Drying Oven 3-23
3-9 Direct Roll Coating . 3-25
3-10 Reverse Roll Coating 3-26
3-11 Flow Coating Machine 3-27
4-1 Rotary Spray Machine and Drying Oven 4-5
4-3 Trends in Nationwide HAP Emissions for All Reporting
Facilities (1987-1990)and Facilities Reporting for All Four Years 4-14
5-1 Thermal Incinerator Unit 5-5
5-2 Regenerative Heat Recovery Unit 5-8
5-3 Catalytic Incinerator Unit 5-10
5-4 Regenerative Carbon Adsorber 5-13
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1.0 INTRODUCTION
One of the major goals of the Clean Air Act Amendments of 1990 (CAAA) is to
achieve compliance with the national ambient air quality'standard for ozone. Title I of
the amendments presents provisions for achieving the ozone standard. Among these
provisions is a requirement that States adopt reasonably available control technology
(PACT) for major sources of VOC's.
Under the amendments, a major source is defined as one with a potential to
emit 100 tons or more of VOC's if that source is located in an area classified as
marginal or moderate nonattainment for ozone. If the area is classified as serious
nonattainment for ozone, the threshold for a major source is lowered to 50 tons per
year. Further, the threshold for a major source is 25 tons per year in an area
classified as severe nonattainment, and 10 tons per year in an area classified as
extreme nonattainment. In addition, Section 184 of the CAAA creates the Northeast
ozone transport region which includes 11 States in the Northeast corridor from
Washington, DC, to Maine. In the transport region, a major source is one with a
potential to emit 50 tons or more of VOC. Major sources in the transport region are
subject to the same requirements as major sources in moderate nonattainment areas.
The determination of RACT can be done on a case-by-case basis, but States
typically adopt RACT as defined by Control Technique Guidelines (CTG's) issued by
EPA. As of 1990, EPA had issued 29 CTG documents and was in the process of
developing an additional 12 documents. The CAAA requires States to adopt RACT for
both major sources in industries covered by CTG's, and for major sources in
industries not covered by any existing CTG.
These provisions of the CAAA have a potential impact on the leather tanning
and finishing industry. Many leather tanning and finishing facilities may be reclassified
as major sources under the stricter requirements of the Act. In addition, a large
number of facilities are located in the Northeast transport region. The EPA has not
issued a CTG for this industry and does not anticipate issuing a CTG document in the
near future. Therefore, States are left with the burden of determining RACT for any
major sources of VOC's in the leather tanning and finishing industry.
1-1
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1.1 Objectives of the Report
The CTC has received a number of calls from State and local agencies
requesting guidance on controlling VOC's from leather tanning and finishing facilities.
One of the objectives of this report is to document existing emission control and
reduction methods currently used in the industry. State and local agencies will use
this information to help determine RACT for facilities in their jurisdiction.
Another objective of the report is to identify and characterize the emissions of
HAP's from the industry. In Title III of the CAM, Section 112(c) requires EPA to
publish a list of categories of major and area sources for regulation that emit one or
more of the HAP's listed in the section. Presently, leather tanning and finishing plants
are not on the list of major or area sources listed for regulation. The information
contained in this report will be used to determine if leather tanning and finishing should
be added to the list.
1.2 Overview of the Report
The information contained in this document has been obtained from a variety of
sources. Contacts were made with numerous State and local agencies that have
leather tanning and finishing facilities located in their jurisdictions. These agencies
supplied available emissions data and information on regulations specific to the leather
tanning and finishing industry. Site visits were made to five facilities, two of which
employ emission control devices. Information was also obtained from sources within
the leather tanning and finishing industry. These sources included trade associations,
suppliers of equipment, and suppliers of finishing chemicals. An extensive literature
search was also conducted.
This report is divided into 6 chapters and 5 appendices. Chapter 2.0 provides a
general description of the industry while Chapter 3.0 describes the key processes
employed in manufacturing leather. Chapter 4.0 characterizes the emissions of VOC's
and HAP's from the industry, and Chapter 5.0 describes applicable emission reduction
technologies. Finally, Chapter 6.0 discusses current State and local air pollution
regulations affecting the industry.
The appendices provide supplementary information related to specific sections
of the report. Appendix A includes all emissions data obtained during the study.
Appendix B is a series of case studies derived from site visits. These case studies
describe emission reduction strategies currently employed by various facilities.
Appendix C contains the full text of all State and local air pollution regulations affecting
the leather tanning and finishing industry along with all available supporting
documentation for these rules. Appendix D lists the facilities identified by various
sources reviewed during the study including emissions data bases, State and local
1-2
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agency emission inventories, and permitting records. Finally, Appendix E is a list of
selected contacts who provided information and assistance in compiling the report.
1-3
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2.0 INDUSTRY DESCRIPTION
Leather manufacturing is one of the oldest industrial processes in the world.
The origins of this craft can be traced to prehistoric times. Early tanning operations
were conducted in open pits using exclusively manual operations. The tanning agents
were plant substances such as oak, hemlock, and chestnut barks. With the arrival of
the industrial age, leather making evolved from a cottage craft to a full scale industry.
The modern tannery uses advanced chemical and mechanical processes to
produce leather having hundreds of different finished characteristics. This leather is
used to produce products such as footwear, upholstery, clothing, gloves, luggage,
personal leather goods, and industrial parts. Production of each type of leather
involves integration of a complex series of operations that must be closely monitored
by experienced professionals.
A distinction can be made between the leather tanning and finishing processes.
Leather tanning involves primarily wet chemical processes that produce a stable,
usable product. Leather finishing involves a number of conditioning and enhancement
processes that give tanned leather distinctive and desirable qualities required by end
users of the material. Some facilities in the industry are only involved with leather
tanning while some are exclusively leather finishers. There are also facilities that tan
and finish at the same location.
The leather tanning and finishing industry has undergone a great number of
changes in recent years. In 1982, there were 342 companies in the industry operating
about 384 facilities. In 1991, the U. S. Industrial Outlook reported only 115 facilities of
significant size that were involved with wet tanning of hides and production of
leather.1
Developing an accurate list of leather tanning and finishing facilities is difficult.
Table 2-1 presents estimates of the number of leather tanning and finishing facilities in
the United States using three sources of information. The 1991 International Leather
Guide lists 225 leather tanning facilities and sales offices while a 1992 report prepared
for EPA listed 133 le.ather tanning and finishing facilities.2'3 A review of available
emissions inventories and EPA data bases revealed 79 facilities conducting leather
tanning and/or finishing. Mr. Frank Rutland of the Leather Industries Research
Laboratory estimates that there are about 125 total facilities in the United States
2-1
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Table 2-1. Leather Tanning and Finishing
Facilities in the United States
STATE
ALASKA
ARIZONA
CALIFORNIA
COLORADO
CONNECTICUT
FLORIDA
GEORGIA
IOWA
ILLINOIS
INDIANA
KENTUCKY
LOUISIANA
MASSACHUSETTS
MAINE
MARYLAND
MICHIGAN
MINNESOTA
MISSOURI
NORTH CAROLINA
NEBRASKA
NEW HAMPSHIRE
NEW JERSEY
NEW YORK
NUMBER OF FACILITIES
ILG'
1
2
8
2
2
2
2
2
8
1
2
0
40
9
1
4
2
4
1
1
5
15
64
EPA REPORT
0
0
4
0
0
2
1
1
3
0
2
1
26
6
1
3
1
2
1
2
1
10
32
EMISSIONS DATA0
0
0
1
1
0
1
0
1
3
0
0
0
6
5
1
3
1
2
1
1
0
5
24
2-2
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Table 2-1. Leather Tanning and Finishing
Facilities in the United States
STATE
OHIO
OREGON
PENNSYLVANIA
SOUTH CAROLINA
TENNESSEE
TEXAS
UTAH
WASHINGTON
WISCONSIN
WEST VIRGINIA
NUMBER OF FACILITIES
ILG*
2
1
8
1
9
4
1
0
20
1
225
EPA REPORT
1
2-
5
0
4
3
2
1
16
0
133
EMISSIONS DATA6
1
0
6
0
4
1
1
0
9
1
79
a Reference 2
b Reference 3
c Toxic Release Inventory (1987-1990), AIRS data base, state inventories and permit information.
2-3
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conducting some form of leather tanning and/or finishing, with about 85 facilities
having some type of finishing operation.4 Most of the plants are located in New York,
New Jersey, Wisconsin, and Massachusetts. A listing of the facilities identified using
emissions inventories and EPA data bases is provided in Appendix D.
The discrepancies in the number of facilities identified in the United States is
indicative of the changes occurring within the industry and the characteristics of the
industry as a whole. Some of the facilities identified by the International Leather Guide
are sales offices or specialty process support operations. For example, some smaller
companies may be involved with only one process of the leather manufacturing
operation such as embossing or cutting. There are also a large number of small
facilities that may not be reported in all data bases.
2.1 Characterization of the Industry
When looking at the leather tanning and finishing industry as a whole, a division
can be made between the larger and smaller companies. The larger companies
typically have integrated tanning, finishing, and marketing operations and employ 400
to 1,000 people. These larger companies usually have in-house research and
development capabilities and have some ability to develop customized coating
formulations and finishing systems. The smaller companies typically have less than
100 employees and rely more heavily on chemical suppliers to provide tanning and
finishing chemicals. They generally do not have the in-house capabilities to develop
new coating formulations and finishing systems.5
Most of the facilities in the industry fall into the category of smaller companies.
As indicated by the 1992 U. S. Industrial Outlook, total 1991 employment by the
industry was about 11,400 people spread among 115 facilities. Therefore, the average
facility has less than 100 employees. This characterization of the industry is important
when considering the availability of resources needed to convert to new technologies
such as water based coatings. The majority of the leather tanning and finishing
facilities have limited technical capabilities.
There are literally thousands of different products that can be produced from
leather. However, the two largest markets for leather are the footwear industry and
the upholstery industry. In 1991, 52 percent of all leather shipments were used to
manufacture footwear. Conversely, the fastest growing market for leather is the
furniture and automotive upholstery industry. It is estimated that in 1991 the
upholstery industry accounted for nearly 35 percent of all leather shipments by value
as opposed to only 7 percent in 1982. This rapid growth is the result of changes in
consumer attitudes and more demand for leather products in furniture and
automobiles.
2-4
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Tables 2-2 and 2-3 provide industry statistics for the cattlehide segment of the
industry. Most of the leather produced in the United States is from cattlehides. As
shown in the tables, production levels have remained relatively stable over the past
few years.8
Continued product development and refinement of existing products is a
standard activity in the industry. Tanneries must react to the changing demands of
their customers and the tanning and finishing process must often be changed to adapt
to these demands. For example, automotive upholstery manufacturers must meet a
wide range of quality standards imposed by the automotive industry. These standards
cover characteristics such as rubfastness, color, and heat resistance. The tannery
must closely monitor all phases of the leather manufacturing process to ensure that
these standards can be met.
Another example can be found in the footwear industry. Footwear styles are
determined by fashion trends that are ever changing. As a result, shoe manufacturers
demand that the leather they purchase match the latest trends. Therefore, tanneries
producing footwear leather have to adapt their tanning and finishing systems to
produce suitable leathers. Since shoe manufacturers apply their own finishes to the
leather they purchase, the finished leather supplied by the tannery must also be
compatible with the finishes being applied by the shoe manufacturer.
The leather tanning and finishing industry is a highly competitive industry.
Competition exists not only within the United States, but also from a vast overseas
leather industry. Over 50 percent of the leather imported to the United States is from
the countries of Argentina, Italy, the United Kingdom, Brazil, and Thailand.7
2-5
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Table 2-2. United States Production of Cattlehide Leather
Unit - 1,000 Equivalent Hides
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
WETTINGS
14,948
15,581
15,105
15,456
14,029
12,616
12,598
12,754
11,475
11,242
13,018
13,021
PRODUCTION
14,790
15,520
15,028 .
15,430
14,021
12,550
12,497
12,846
11,569
11,329
13,175
13,042
DELIVERIES
14,816
15,461
15,053
15,427
13,971
12,556
12,603
12,914
11,548
11,443
13,291
13,261
Source: U.S. Leather Industries Statistics, 1992 Edition.
Note: Wettings refer to the number of hides soaked in the wet ends process. Production
refers to finished hides, while deliveries refer to the number of finished hides shipped to
customers. Deliveries can exceed production in a given year if hides finished in one year
are not shipped to customers until later years.
2-6
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Table 2-3. Tanners' Stocks of all Cattlehide and Leathers
Unit - 1,000 Equivalent Hides
(Stocks as of December 31)
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
RAW
870
990
1,140
1,160
1,070
487
51
356
348
377
787
928
1,323
1,491
1,584
1,638
2,210
3,399
NR
PROCESSED
2,258
2,362
2,230
2,229
2,304
2,133
2,015
2,162
2,210
2,294
2,319
2,328
2,396
2,450
2,470
2,318
2,229
2,072
2,058
FINISHED
908
975
568
745
654
672
657
534
590
535
563
535
457
406
418
392
390
397
413
TOTAL
4,036
4,327
3.938
4,204
4,028
3,283
2,723
3,052
3,148
3,206
3,669
3,791
4,176
4,347
4,472
4,348
4,829
5,868
NR
Source: U.S. Leather Industries Statistics, 1992 Edition.
Note: Inclusion of raw stocks in this summary report was discontinued in 1991 due to
insufficient data.
2-7
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2.2 References
1. U. S. Industrial Outlook, 1991. United States Department of Commerce,
International Trade Administration.
2. 1991 International Leather Guide.
3. Science Applications International Corporation. Assisting the New England States
in Implementing Reasonably Available Control Technology at Leather Finishing
Plants. Final Report submitted to the U. S. Environmental Protection Agency,
Office of Air Quality Planning and Standards. July 31, 1992. Appendix B.
4. Telecon. Mitsch, B.F., Alpha-Gamma Technologies, Inc., with Rutland, F., Leather
Industry Research Laboratory. March 3, 1993. Clarification of information
collected regarding the leather tanning and finishing industry.
5. Reference 4.
6. U. S. Leather Industries Statistics. 1992 Edition. Leather Industries of America Inc.
Washington, D. C.
7. Reference 6.
2-8
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3.0 LEATHER TANNING AND FINISHING PROCESSES
Hides and skins from many animals can be tanned and" finished. These animals
include cattle, sheep, goats, pigs, deer, horses, and reptiles. In order to simplify the
description of the tanning and finishing process, the discussion in this section focuses
on cattle hides used to produce leather used for upholstery, footwear, and other
fashion goods.
Production of finished leather is a complex procedure that includes many
chemical and physical processes. These processes are interrelated and each can
have an effect on the characteristics of the finished leather. In this section, the
chemical and mechanical processes used to produce finished leather will be
discussed. A process flow diagram is provided in Figure 3-1.
Leather tanning and finishing processes can be divided into wet operations and
dry operations. The wet operations include all of the processes required for leather
tanning. These processes include steps to purify and stabilize the collagen content of
the hide. Collagen is the protein responsible for the strength and toughness of
leather. Dry operations consist mostly of processes that enhance the natural
characteristics of the leather. Dry operations include the leather finishing processes
which are responsible for most of the VOC and HAP emissions.
Each of the major wet and dry operations are discussed below. The
information provided in the following sections was drawn from three primary sources:
a) the Kirk-Othmer Encyclopedia of Chemical Technology;1 b) Ullman's Encyclopedia
of Industrial Chemistry;2 and c) Leather Facts.3
3.1 Wet Operations
Historically, wet operations have been divided into three phases: a) the
beamhouse; b) the tanyard; and c) the coloring department which includes the
retanning, coloring, and fatliquoring operations. The term beamhouse was derived
from the way that hides were prepared for tanning using a beam or log to support the
hide while it was hand treated. The tanning process was conducted in open pits often
dug in the ground. Although modern tanneries have more advanced equipment for
processing hides, the terms beamhouse and tanyard are still used. Figure 3-1 uses
these terms in showing the flow through the tanning and finishing process.
3-1
-------
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3-2
-------
Raw cured hides arrive at a tannery from slaughter houses and meat
processing plants. The hides are generally preserved following slaughter to prevent
putrefaction. The most common method for preserving a hide is through brine curing.
Hides are placed in large vats containing a concentrated salt solution and soaked for
up to 24 hours. After the hides are removed from the vat, dry salt is added and the
hides are bundled for shipment to the tannery.
Upon arrival at the tannery the hides are sorted and weighed. Most hides have
been fleshed by the slaughter houses. Fleshing is the removal of excess flesh and
fatty material from the hide. In cases where the hides have not been fleshed, fleshing
is conducted prior to the hides entering the leather manufacturing process. This
process begins with a series of wet operations.
3.1.1 Soaking
The objective of the soaking process is to remove salt and restore moisture lost
as a result of salt curing. The soaking process involves placing the hides in large
mixing drums containing water and chemical additives (Figure 3-2). The hides are
constantly moved in the drums to ensure flexing of the hides and absorption of
moisture. The chemical additives include wetting agents and disinfectants that
facilitate the remoisturizing process and clean the hides.
The soaking process can take from 8 to 20 hours depending on the thickness
of the hides. Following soaking, fresh water is introduced to the mixing drums while
the water used for soaking is continuously removed. This wash cycle removes excess
salt, dirt, and biological debris from the drums.
3.1.2 Unhairing
The unhairing process takes place in the same drums or vessels used for
soaking. Unhairing is usually accomplished using chemicals. Concentrated solutions
of calcium hydroxide and sodium sulfide are added to the drums containing the hides
and water. The objective of the unhairing process is to remove hair, loosen the outer
layer of the skin covering the grain of the hide (the epidermis), and remove soluble
skin protein. Care is taken during this process to avoid damaging the collagen fibers
of the hide. Collagen fibers are the essential component of leather.
The chemicals used in the unhairing process raise the pH of the hides and
cause the hides to swell. Hides may swell to twice their normal thickness during
unhairing.
3-3
-------
Figure 3-2. Mixing Drum Used in Soaking and Unhairing
3-4
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3.1.3 Bating
Bating takes place in cylindrical drums with hollow axles (Figure 3-4).
Chemicals and water are introduced through pipes inserted into the hollow axles of the
drums. The objective of the bating process is to remove the alkaline chemicals that
were used in the unhairing process, and remove remaining undesirable components in
the hide.
Once the pK of the hide has been adjusted using chemical additives such as
ammonium sulphate or ammonium chloride, animal enzymes are added to the drum.
These enzymes are referred to as the bate. The enzymes act ta destroy hair roots
and pigments remaining in the hides. The result of the bating process is a cleaner,
softer hide that is nearly ready to be tanned.
In the case of pigskin and sheepskin, an additional chemical step is employed
following the bating process. Pig and sheep skins contain excess fats and greases
that must be removed prior to tanning. Degreasing using solvents is one method of
extracting these unwanted components of the hide. Solvent degreasing is
accomplished by exposing the hides to a solution containing solvents and surfactants.
Commonly used chemicals used for solvent degreasing include kerosene, stoddard
solvent, nonionic and anionic surfactants, and solvents such as trichloroethylene and
perchloroethylene. Since volatile compounds are used for degreasing, this process is
a potential source of VOC emissions.
3.1.4 Pickling
Prior to tanning, the pH of the hides must once again be adjusted. The
objective of the pickling process is to lower the pH of the hides using salts and acids.
Pickling is accomplished in the same drums used for bating and usually takes only a
few hours to obtain full penetration of the chemicals into the hides.
3.1.5 Tanning
The objective of the tanning process is to stabilize the collagen fibers in the hide
so that they are no longer biodegradable. It is the tanning process that produces the
substance known as leather. The most common method of tanning used in the
United States is referred to as chrome tanning. Over 90 percent of the leather
produced in this country is chrome tanned. Chrome tanning is the preferred method
because it can be accomplished in shorter time periods than other methods such as
vegetable tanning, mineral tanning, and resin tanning. Chrome tanning also produces
leather that is highly stable and serviceable in use.
The tanning process takes place in the same drums used for bating and
pickling. Tanning is complete in about 4 to 6 hours. The tanned hides are removed
3-5
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Figure 3-3. Drum Used for Bating, Pickling, and Tanning
3-6
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from the drums and placed in boxes located beneath the drums. The boxes have
porous bottoms that allow excess tanning solution to be drained from the hides.
Hides that have been chrome tanned have a characteristic blue color, and are referred
to as "blues" or "wet blues."
There are some chromium emissions generated by leather tanning and
finishing. In the Toxic Release Inventory data presented in Section 4.0, some
tanneries report small quantities of chromium air emissions. It is uncertain whether
these emissions are generated by the actual tanning process or by subsequent
operations.
3.1.6 Trimming and Siding-
Following tanning, hides are removed from the mixing drums and prepared for
additional mechanical operations. Undesirable portions of the hide are trimmed using
hand knives. As shown in Figure 3-4, the head (section A) and belly portions
(sections F or G) are trimmed. These areas of the hide do not make good leather and
can interfere with some tanning and finishing equipment.
The siding operation involves cutting the hides mechanically from head to tail
along the backbone. This creates a left side and a right side, both of which are
referred to as a "side" of leather. From this point, many tanneries process sides as
opposed to the whole hide. However, tanneries that produce leather for upholstery
products do not cut the hide into sides. They process the whole hide. Tanneries that
process sides are referred to as side leather tanneries while those that process the
whole hide are referred to as whole hide tanneries. For the purposes of simplicity, the
word "hide" will be used generically while discussing the remaining tanning and
finishing processes in this section.
3.1.7 Splitting
Following the tanning process, excess moisture is removed from the hides
using mechanical devices. Wringing machines similar to a clothes wringer are used to
squeeze excess moisture from the hides. Demoisturizing can also be accomplished
using vacuum presses, but this method of demoisturizing is more time consuming
than using wringers.
The tanned hides are now ready to be split. The thickness of hides is highly
variable. In fact, the thickness of the various parts of a single hide may vary
significantly. A splitting machine is used to correct the thickness of the hides. Splitting
creates a uniform thickness across an entire hide, and also allows the tannery to
produce hides of different thicknesses depending on the requirements of the leather
product being manufactured.
3-7
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Head = A
Shoulder = B or C
Bend = D or E
Belly = F or G
Side = A+B + D + F or
Crop = A+B + D or
Back = B + D or C-t-E
Croupon = D+E
Figure 3-4. Sections of a Cattle Hide Used for Leather Making
-------
The splitting machine cuts the hides laterally, producing a top layer and a
bottom layer. The top layer or grain portion of the hide will have a uniform thickness.
This portion of the hide is the most desirable portion for producing leather. The
bottom or flesh layer will have varying thicknesses and is referred to as the "split."
Splits can be used to make suede leather or can be used to make products such as
leather dog bones. Some tanneries sell the splits in the wet blue stage to other
tanneries or manufacturing facilities that make these products. Figure 3-5 shows a
splitting machine.
Following splitting, additional shaving of the hide is performed to ensure uniform
thickness prior to the final wet end processes.
3.1.8 Retanning
Up to this point, most of the wet end processes are standardized throughout
the industry. The wet blue hides that result from chrome tanning are sold in
commodity markets throughout the world and have relatively consistent characteristics.
The next three wet end processes begin to impart unique characteristics to the leather.
The first of these processes is referred to as retanning. Retanning is
accomplished in the same type of drums used in the initial tanning process.
Vegetable, mineral, or synthetic agents are used in the retanning process. The
objective of retanning is to begin developing the end use properties of the leather.
The retanning process helps to soften the leather and can bleach out the bluish color
left by the initial tannage. Retanning takes about 1 to 2 hours.
3.1.9 Coloring
Following retanning, the hides remain in the same drum and are colored using
a wide range of chemical dyes. The dyes used in the coloring stage reflect the colors
desired in the finished product. There are hundreds of dyes and other products that
can be used to color leather.
3.1.10 Fatliquoring
The final wet chemical process is known as fatliquoring. In the fatliquoring
process, animal, vegetable, and mineral fats and oils are added to the drums
containing the hides. Since these substances are not soluble in water, chemical
additives are used to allow dispersal. The type and amount of fatliquor influences the
softness of the finished leather.
4
After fatliquoring, the leather is mechanically stretched, smoothed, and
compressed to remove excess moisture. At this point, the hides have a moisture
3-9
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a = unsplit hide
b = grain layer
c = flesh layer
d = cutting knife
Figure 3-5. Splitting Machine
3-10
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content of about 60 percent and are ready for additional processing in the dry end
operations.
3.2 Dry Operations
After passing through the beamhouse, tanyard, and coloring operations, the
leather manufacturing process moves to the finishing room. In the finishing room, dry
operations are conducted such as drying, conditioning, staking, buffing, and finishing.
The objective of these dry operations is to produce a product that has uniformity,
appearance characteristics, and resistance to scuffing and abrasion desired in a
commercial product such as upholstery or footwear. Each of the primary dry
processes are discussed below.
3.2.1 Drying
The moisture content of the leather is reduced using various methods.
Typically, the drying process reduces the moisture content from about 60 percent to
nearly 10 to 15 percent. Hides that have been dried are referred to as crust leather.
The four commonly used methods of drying leather are hanging, toggling, pasting,
and vacuum drying.
Hang drying involves hanging the leather over horizontal bars and hanging in a
drying loft. In toggle drying, the leather is stretched over a frame and secured with
toggles. One hide can be secured to each side of the frame, and then the frames are
slid into channels in the drying oven.
In paste drying, hides are attached to flat plates using a paste solution.
Operators stretch and smooth the hide to the plate using manual instruments. One
hide is pasted to each side of the plate, and the plates move into the drying oven on
conveyors. The drying time for hang drying, toggle drying, and paste drying is about
4 to 7 hours.
Vacuum drying is the fourth type of drying. In vacuum drying, the hide is
placed on a heated steel plate then covered by a perforated steel plate wrapped by a
felt of cloth. A vacuum is pulled on the hide thereby extracting the moisture. Vacuum
drying takes about 3 to 8 minutes. The hides must be manually placed on the plates,
and only a small number of hides can be dried at any given time. Vacuum drying is
typically used as a supplement to other drying techniques.
3.2.2 Conditioning
4
Following the drying step, the leather is generally suitable for finishing.
However, the drying operation can render leather too hard for specific uses such as
footwear and garments. The objective of the conditioning step is to remoisturize the
3-11
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leather by applying fine mists of water to the surface, and allowing the moisture to
seep into the leather during overnight storage. The moisture content following
conditioning is about 15 to 25 percent.
3.2.3 Staking and Milling
The purpose of staking and milling is to mechanically soften the leather.
Staking (along with fatliquoring) is responsible for the softness of the finished leather.
Staking and milling can be accomplished by two methods. The first method involves
mechanical softening using an automatic machine that flexes and stretches the leather
using a series of oscillating pins (Figure 3-6). The second method, referred to as dry
milling, is similar to using a clothes dryer in a domestic household. Previously dried
leather is placed in a large drum where it is tumbled as necessary to achieve the
desired softness.
3.2.4 Buffing
The final dry process prior to finishing is the buffing operation. The objective of
buffing is to smooth the grain of the leather to enhance the finishing process. Buffing
is achieved using a sanding cylinder that is covered with an abrasive material similar to
sandpaper. Operators control the degree of buffing for a particular type of leather.
The buffing process produces leather that has a smooth, relatively uniform texture.
Leathers that are not buffed are referred to as full grain leathers.
3.3 Leather Finishing Operations
Leather finishing is an additional dry operation that is discussed separately
because of the significance of this process in the production of VOC and HAP
emissions. The objective of leather finishing is to enhance the appearance of the
leather and to impart stain and abrasion resistance qualities to the material.
Leather finishing involves an almost limitless combination of options.
Depending on the specific end use of the leather, a variety of coatings can be applied
during the finishing process using a number of different application methods.
Typically, 3 to 5 coats of finish are applied to the leather although the actual number of
coatings can vary depending on the desired characteristics of the end product.
3.3.1 Coatings Used for Leather Finishing
Coatings can be categorized into three general classes: base coats,
intermediate coats, and top (or finish) coats. Characterization of all coatings into just
three classes is somewhat of an oversimplification. However, these classifications are
commonly used in the industry. Base coats are used to smooth out the leather
surface by covering up faults in the leather grain, staining or coloring the leather, and
3-12
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a = leather
b = metal pin
c = vibrating plate
d = foamed rubber plate
e = guide lever
f = guide roll
Figure 3-6. Staking Machine with a Vibrating Plate (A) or Lever (B)
3-13
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serve as a penetrating or flow aid. Intermediate coats can also be used to impart
color or stains to the leather and serve as an adhesive coating for the top coat. Top
coats are responsible for protecting the leather from abrasion and give the leather
desired properties such as resilience and gloss.
Coatings can also be referred to by function. Functional classifications were
used in the NESCAUM report on the leather finishing industry.4 Functional
classifications include impregnation, base coat, top coat, water proofing, stain, and
antique coats. Impregnation refers to a heavy coating applied prior to the base coat
that serves as a primer coating for subsequent coating applications. A water-based
material is usually used for impregnation. Waterproofing is usually considered a
separate process from finishing, and involves application of silicones or other water
resistance chemicals. Finally, antiquing can be a manual or machine applied coating
used to impart special effects on the leather.
Hundreds of coating formulations are available for base, intermediate and top
coats. Each coating formulation has unique chemical and physical characteristics and
is applied as needed to meet end-use requirements of the leather. Coating
formulations can be classified into one of three categories: lacquers, lacquer emulsion,
and water-based coatings. Although there are no strict definitions for each of these
categories, it is generally accepted that lacquers are the higher VOC-laden coatings,
lacquer emulsions contain a mid-range of organic solvents, and the water-based
coatings contain the lowest concentrations of VOC's.
Until a decade ago, lacquers were the predominant type of coating formulation
used in leather finishing. These resin-based coatings contain approximately 70-95
percent organic solvents by weight. The remaining material are solids such as
pigments and additives. The pigments are finely divided organic or inorganic material
that impart color. The additives, usually organic resins and polymers, serve as a
binder between the pigment and the leather substrate and give the coating desired
characteristics such as gloss and scuff resistance. Lacquer coatings have several
unique properties such as low surface tension, excellent flow properties, and quick
drying times. However, the solids-carrying capacity is considered low, usually 5 to 10
percent.
Lacquer emulsions are formulations with properties between those of lacquers
and water-based coatings. These coatings are similar to lacquers as approximately 60
percent of the solution is organic solvents. However, additives such as surfactants are
used to make the coating solids water-miscible. The leather finisher then dilutes the
material with water in appropriate amounts and the final emulsion may contain
between 20 and 30 percent water. Lacquer emulsions have about the same solids-
carrying capacity as lacquers.
3-14
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Water-based coatings typically contain less than 10 percent organic solvents,
and have become more popular over the last decade as formulation technology has
developed and the characteristics of these materials have improved. Their popularity
is due in part to the reduced VOC emission characteristics, their increased solids-
carrying capability, and subsequent improvements in the working environment by
minimizing the use of organic solvents.
Table 3-1 shows a comparison of chemical characteristics of lacquer, lacquer
emulsion, and water-based coatings.58 Table 3-2 gives a comparison of the typical
composition of lacquer and water-based top coat formulations. There is a trend in the
industry towards increased use of water-based coatings. Currently, most base
coatings are water-based formulas and some intermediate and top coatings are also
water based. Table 3-3 shows the increased sales of water-based coatings by a
major coatings supplier to the leather industry.7 Conversations with various industry
representatives confirm this trend.
Water-based coatings have the advantage of being able to hold more solids in
the primary solution (water). As compared to lacquers, water-based coatings can hold
about 50 percent more solids by weight. These properties are important in base and
intermediate coatings where less water-based coatings need to be applied than
comparable lacquers. Since gloss, resiliency and other surface characteristics are of
less concern at these earlier coating applications, water-based materials are suitable
for many types of leathers.
The transfer efficiency of solids also increases with the use of water-based
coatings. Because of the high-solids content and low volatility of water-based
coatings, the amount of coating used decreases. This can offset some of the costs
associated with moving from lacquer to water-based formulations.
The reduction in VOC content has several major advantages from an
environmental and safety perspective. The use of water-based coatings not only
decreases VOC emissions, but usually minimizes HAP emissions associated with many
lacquer formulas. Use of water-based coatings also improves the working
environment by limiting the use of toxic and flammable chemicals.
Despite the advantages, water-based coatings present a variety of problems,
particularly when used as top coats. The physical properties of water-based top coats
affect flow control of the coating during application. This can affect the gloss, water
resiliency and scuff-resistance of the final product. Many water-based top coats also
require intermediate cross-linking agents to adequately bind the base coat and top
coat. Several of these cross-linking agents are also toxic. Finally, the leather takes
longer to dry using water-based coatings.
3-15
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Table 3-1. Comparison of Lacquer, Lacquer-Emulsion
and Water-Based Top Coat Systems
Property
Application
Solids (%)
Wt.% Solvent
(as applied)
VOC (#/gal. less
water supplied)
Gallons to Finish
100 Sides
Pounds Organic
Lacquers
5-15
75-95
5.0-6.5
9
46.4-61.8
Lacquer
Emulsions
5-20
40-60
5.0-6.5
7-
22.8-30.9
Water-Based
Coatings
20-30+
5-15
0-3..0
4.5
0-4.0
Solvent Emitted per
100 Sides
3-16
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Table 3-2. Generic Coating Formulations
LACQUER
WATER-BASED
Organic Solvents
Binders
Plasticizers
Pigments
Other Additives
Conditioners
Silicones
Dulling Agents
Feel Modifiers
Water
Organic Solvent or Coalescents
Binders
Surfactants
Pigments
Other Additives
Leveling Agents
Penetrators
Thickeners
Fillers and Dulling Agents
3-17
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Table 3-3. Top Ten Products by Year and VOC Content
(Alpha-Numeric Characters Represent Product Formulations')
1986
D**
I**
G**
L
£**
V
M
K
F**
H**
Average VOC
Content
# of VOC-based
products in top ten
%
VOC
92.7
88.7
81.8
0.0
85.4
7.2
0.0
0.2
82.2
95.9
53.4
6
1989
S
W
I**
E**
AA
N
O
P
A
9
M
%
VOC
7.7
9.9
88.7
85.4
48.6
4.0
0.0
4.1
4.6
0.0
25.3
2
1990
S
W
I**
T
B
AB
O
Q
M
U
%
VOC
7.7
9.9
88.7
11.9
10.0
48.5
0.0
4.0
0.0
11.8
19.2
1
1992
W
X
R
O
C
AC
Y
J
S
z
% VOC
12.1
13.0
8.9
0.0
8.3
47.8
6.1
0.0
7.7
13.9
11.8
0
**
Each letter or group of letters depicts a different product sold to the leather
finishing industry during that year.
Indicates Organic Solvent-Based Finishing System Component
3-18
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Some of the problems experienced with water-based top coats are the result of
the unique properties of water rather than the types of polymers used. For example,
the surface tension of water is one factor that causes problems with water-based top
coats. Table 3-4 shows the surface tensions of various solvents, with water topping
the list. Figure 3-7 shows a comparison of contact angles with aqueous and with
organic solvent-containing lacquers when they are applied to the leather surface. If
the contact angle is less than 90 degrees, as with water, the liquid beads up and does
not spread spontaneously over the surface. This property of water leads to
considerable problems with spreading and levelling of aqueous-based top coats.8 In
a recent survey conducted for EPA, the leather finishing industry indicated that poor
flow characteristics were considered the number one problem of water-based coats.9
Drying times are also an important cost factor for leather finishing. The
increased drying times resulting from the use of water-based coatings is reflected in
costs such as labor, energy requirements of ovens, the number of ovens, space
requirements, and inventory requirements. Finally, use of water-based top coats can
present problems with meeting market demands. For example, shoe manufacturers
that apply additional finishes to the shoes need to have leather finished with a coating
compatible with their finish coating material. In addition, some water-based top coats
do not provide the desired look and feel desired by many end-users.
3.3.2 Application Methods for Leather Finishing
There are three common methods of finishing leather. These methods Sre
spray coating, roll coating, and flow coating. Spray coating is the most prevalent in
the leather tanning and finishing industry. Spray coalers can consist of rotary
sprayers, oscillating sprayers, stationary sprayers, or hand spray operations.
3.3.2.1 Spray Systems
The most commonly used spray system in leather finishing is the rotary spray
machine. The rotary sprayer consists of a series of spray arms each having a spray
gun located at the extremity of the arm. The spray arms are mounted on a central
shaft that rotates as the leather passes underneath on a conveyor. Coatings are fed
to the spray guns through a vacuum hose immersed in a drum or other vessel
containing the coating.
Most rotary spray machines are controlled by optical scanners and
microprocessors that minimize overspray. The leather passes through the optical
scanner prior to entering the spray booth. The scanner records the outline of the hide
and electronically triggers the spray guns to optimize the amount of coating that
contacts the hide. Rotary spray machines can have 4, 8, or 16 guns. The 4 and 8
gun machines are typically used to spray side leather while 16 gun machines are
better suited to spraying full hides.
3-19
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Table 3-4. Surface Tensions of Various Solvents
SOLVENT SURFACE
TENSION
(dynes/cm)
WATER 73
ETHYLENE GLYCOL 48
CYCLOHEXANONE 35
XYLENE 30
ETHYL GLYCOL 28
TOLUENE 28
METHYL ETHYL KETONE 25
MINERAL OIL 30
SILICONS OIL 23
3-20
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Contact Angle <90 degrees
Substrate: Leather with Grounding
Contact Angle >90 degrees
Top Coat
Substrate: Leather with Grounding
Figure 3-7. Contact Angles of Aqueous and Organic Leather Coatings on a
Leather Substrate
3-21
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Figure 3-8 shows a typical rotary spray booth. Drying ovens usually follow each
spray booth used in the finishing system. Various types of drying ovens are used in
the industry. Examples of drying ovens include catalytic ovens, steam-heated ovens,
and gas-fired ovens. Both the spray booth and the drying oven are typically enclosed,
either partially or fully. High volumes of air are typically exhausted from the spray
booths and dryers to provide worker protection and prevent development of explosive
mixtures.
Other types of spray machines used in finishing leather include the oscillating
spray machine, the stationary spray machine, and the hand operated spray gun. The
oscillating spray machine consists of a single arm that swings back and forth as the
leather passes underneath. The angle of the spray gun can be adjusted to impart
unique characteristics on the leather. Stationary spray machines consist of a series of
spray guns that remain in place as the leather passes underneath. Both of these
types of spray machine can also be optically controlled.
Finally, hand operated spray guns are used for various purposes in finishing
leather. In larger facilities, hand operated spray guns are used for touch up, special
effects, and testing of coatings for texture and color. In some of the smaller facilities,
hand operated spray guns may be the primary method of finishing the leather. Spray
booths used for manual spraying are usually enclosed on three sides and vented
through an exhaust system.
Various types of spray guns can be used with each of the spray systems
mentioned above. The design of the spray gun can influence the transfer efficiency of
the coating. The types of spray guns used in leather finishing include: conventional
air spray guns; airless spray guns; air-assisted airless spray guns; and high volume
low pressure spray guns. These different spray guns are discussed in greater detail in
Section 5.0.
All of the spray machines are usually equipped with some type of system to
catch overspray and control particulate air emissions. One method used to catch
overspray is the placement of a water bath or plastic sheet beneath the conveyer
moving the hides through the machine. Overspray is captured by the water or plastic.
In some cases, coating caught by a plastic sheet can be placed back in the coating
drum and resprayed.
Water curtains are the most commonly used technique to control particulate
emissions. The spray booth is kept under negative pressure and the exhaust is
collected and vented through ductwork to either an additional pollution.control device
or the atmosphere. The exhaust passes through a water curtain that absorbs the
particulates in the gas stream. Although water curtains are used by most facilities, dry
filters can also be used for particulate control.
3-22
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Figure 3-8. Rotary Spray Booth and Drying Oven
3-23
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3.3.2.2 Roll Coating Machines
Roll coating machines have limited use in leather finishing because of the
relative thickness of the coating applied by this method. Roll coating is usually used
to apply base coats that are relatively thick. In roll coating, the coating is applied
directly from a rubber coated or steel roller. The coating is fed to the roller using a
vacuum hose connected to a reservoir of coating material. The coating is picked up
by the roller and transferred to the leather.
»
One advantage of roll coating is that there is no overspray so transfer
efficiencies approach 100 percent. The disadvantages of this technology are the
potential for uneven application of the coating, lack of penetration, and bunching of the
leather as it passes through the rollers.
Roll coating machines can be either direct roll or reverse roll machines.
Rgure 3-9 shows a typical direct roll coating machine. Figure 3-10 shows a reverse
roll coating machine.
3.3.2.3 Flow Coating Machines
Flow coaters, or curtain coaters, can be used to deliver a heavy coating to the
leather. In a flow coater, the coating is applied to the leather by controlled pouring of
the coating directly to the leather surface. For example, in one type of flow coater, the
coating flows from a reservoir over a thin barrier in a motion resembling a waterfall.
Because of the nature of the application method, the transfer efficiency of flow coating
is close to 100 percent. Figure 3-11 shows a typical flow coater.
3.4 Additional Dry Operations
Following the finishing process, there are a number of additional dry operations
prior to shipping the finished leather to the end user. These additional operations
include plating, grading, and measuring.
The plating process is used to either smooth the surface of the finished leather
or to impart grain textures using mechanical processes. Plating is accomplished by
presses capable of applying high pressure to the leather. The presses can be either
manually or automatically operated. The action of the plating process is similar to that
of an iron press in a commercial laundry. The high pressure applied to the leather can
simply smooth out the surface of the leather or dye cast plates can be used to create
patterns in the leather. Plating is used to simulate animal characteristics such as
snake skin or to emboss patterns typically found in automotive leather.
Following plating, the leather is graded and measured. Leather is graded for
feel, uniformity of color, thickness, and the presence of defects.
3-24
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a = coating
b = application roll
c = transport roll
d = scraper
e = leather
f = conveyor belt
g = roll for distributing the coating
Figure 3-9. Direct Roll Coating Machine
3-25
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Applicator Roll
\
Into Oven
Applicator Roll
Pickup Roll
Pickup Roll
Figure 3-10. Reverse Roll Coating Machine
3-26
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Figure 3-11. Flow Coating Machine
3-27
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3.5 Waterproofing Operations
Waterproofing is treated as a process separate from typical wet and dry
operations. Waterproofing is a specialty process that is used for specific products and
is also a source of VOC and HAP emissions. Although the term waterproof is
commonly used, there are actually three separate properties that can be imparted on
the leather. These properties are water penetration resistance, water absorption, and
water repellency. The methods used to achieve these properties are different.
Water penetration resistance refers to the ability of water to penetrate through
the thickness of leather during flexing. This is a specific property required in military
combat boots, some work boots, and recreational footwear. The only available means
of achieving required levels of water penetration resistance is by silicone impregnation
using a flow or curtain coater.
Water absorption properties are also required in military combat footwear as
well as some domestic footwear leathers. This property can be achieved by silicone
impregnation and also through the use of hydrophobic retanning in the wet end
process. Depending on the degree of water absorption required, water absorption
can be achieved using either technology.
Finally, water repellency is a surface phenomenon that can be achieved through
conventional finishing technology. Repellency is obtained by putting a suitable barrier
on the surface of the leather and is not dependent on the properties of the crust
leather. All three of these technologies are used to produce different types of leather
products. Often, more than one technology is used in combination.
3.5 References
1. Kirk Othmer Encyclopedia of Chemical Technology. Third Edition, Volume 14.
John Wiley and Sons. New York, New York. 1991.
2. Oilman's Encyclopedia of Industrial Chemistry. Fifth Edition, Volume A15.
3. Leather Facts. Booklet published by the New England Tanner's Club, PO Box 371,
Peabody, MA 01960.
4. Science Applications International Corporation. Assisting the New England States
in Implementing Reasonable Available Control Technology at Leather Finishing
Plants. Final Report submitted to the U. S. Environmental Protection Agency,
Office of Air Quality Planning and Standards. July 31, 1992.
5. Walther, W. All-Aqueous Systems for Leather, Problems and Solutions. Journal
of the American Leather Chemists Association. Volume 83, p 74. 1988.
3-28
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6. Biles, J. Parameters in the Application of Water-based topcoats. Journal of the
American Leather Chemists Association. Volume 85. 1990.
7. Letter and attachment from Ossoff, S.B., Stahl USA to Mitsch, B.F.,
Alpha-Gamma Technologies, Inc. Februarys, 1993.
8. Reference 6.
9. Reference 4.
3-29
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4.0 CHARACTERIZATION OF EMISSIONS
This section includes a discussion of the sources of VOC and HAP emissions
from leather tanning and finishing and the factors affecting emissions. In addition,
plant-specific and industry-wide VOC and HAP emissions are quantified using existing
emissions data.
4.1 Sources of VOC and HAP Emissions
There are a number of sources of VOC and HAP emissions in the leather
tanning and finishing process. The major sources of emissions are:
a) Leather finishing operations;
b) Waterproofing operations;
c) Solvent degreasing operations; and
d) Miscellaneous fugitive sources.
Table 4-1 lists the air pollutants emitted from leather tanning and finishing
operations. These chemicals were identified in the Toxic Release Inventory (TRI) for
the years 1987-1990, and also in data obtained from operating facilities. Both VOC's
and HAP's are listed in the table. Table 4-2 shows the relative contribution of air
emissions from the beamhouse, tanyard, and finishing operations.1 With the exception
of solvent degreasing, all of the major sources of emissions listed above are part of
the finishing operation. As shown in the table, finishing operations are the major
source of VOC's in the leather tanning and finishing industry. The data in the table
also indicate that the greatest producer of VOC emissions is the spraying of VOC-
laden coatings in the finishing process. Each of the major sources of VOC emissions
are discussed separately below.
4.1.1 Leather Finishing Operations
Leather finishing operations are the single largest source of emissions in the
leather tanning and finishing industry. In States that have regulations impacting the
industry, the regulations are directed specifically at the leather finishing operation.
4-1
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Table 4-1. Air Emission Compounds from Leather Facilities*
Chemicals Classification
Acetone
Cyclohexane
Cyclohexanone
n-Butyl Alcohol non-HAP VOC's
Ethanol
2-Ethoxyethanol
Isopropyl Alcohol
2-Methoxyethanol
Naptha ^
Benzene
Cumene
Diethanolamine
Ethylene Glycol
Glycol Ethers
Formaldehyde
Methanol HAP VOC's
Methyl Chloroform
Methyl Ethyl Ketone
Methyl Isobutyl Ketone
Methylene Chloride
Tetrachloroethylene
Triethyl Amine
Toluene
Xylene (mixed)
Chlorine
Chromium
Chromium Compounds non-VOC HAP's
Hydrochloric Acid
Manganese
Manganese Compounds
* Sources include the TRI database, chemical industry, and the leather industry.
4-2
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Table 4-2. Emissions from Leather Processing Monitored
in the United Kingdom During 1990
Source Pollutant Quantity (mg/m3)
Crust Leather Operations
Beamhouse — Hydrogen sulfide up to 7.1 *
Ammonia up to 35.5 *
Tanyard Ammonia up to 14.2 *
Finishing Operations
Conveyorised Sprayer
Water-diluted nitrocellulose VOC 7 to 800 **
Solvent-diluted nitrocellulose VOC 1200 to 3700 **
Finish Dryer
Water-diluted nitrocellulose VOC nil to 100 **
Solvent-diluted nitrocellulose VOC 400 to 1200 **
* Workplace levels, converted to mg/m3.
** Discharge to air via exhaust systems.
4-3
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As described in Section 3.0, leather finishing involves the application of various
coatings to the surface of the leather. Typically, 3 to 5 coats are applied to any one
piece of leather. Various methods of application are used to apply the coatings with
spray coating being the most commonly used approach. Other application methods
include roll coating, reverse roll coating, and curtain coating.
Figure 4-1 shows a typical rotary spray coating booth and drying oven. Air
emissions result from the solvent flashing before the coating hits the surface of the
leather, overspray of the coating, and bounce back of the coating from the surface of
the leather. Most spray coating booths are partially or fully enclosed. Solvent vapors
are collected in the spray area and vented to the atmosphere or a control device.
Each spray booth is usually followed by a drying oven. Additional air emissions
are generated from the drying oven as a result of the drying and evaporation process.
The drying ovens are partially or fully enclosed and are usually vented to the
atmosphere or a control device. There is also a flash-off zone located between the
spray booth and the drying oven where VOC can be released to the air. The flashoff
zone between the spray booth and the drying oven may or may not be enclosed.
High volumes of air are typically exhausted from the spray booths and the
drying ovens. Dilute quantities of VOC's are present in the exhaust. Two plants
visited during the course of this study vented the exhaust from the rotary spray booths
and drying ovens to a thermal incinerator. Emissions testing conducted on the inlet air
to the incinerators showed VOC emission rates ranging from 120 and 370 pounds per
hour.2'3
Other types of spray booths are also sources of air emissions. Hand spray
booths and oscillating spray booths produce emissions due to overspray, flash-off,
and bounceback. Roll-coating machines and flow coating machines produce less
emissions because the transfer efficiency of the coating material is much higher.
Transfer efficiencies and a comparison of emissions potential of these spray machines
are discussed further in Section 5.0.
4.1.2 Waterproofing Operations
Waterproofing is considered a separate operation from leather finishing.
Waterproofing involves treatment of the leather with a waterproofing agent such as
silicone or a fluorocarbon. Waterproofing agents are often applied using a curtain
coating process that dispenses the agent in a solution having "an organic solvent.
Emissions result from flashoff of the solvent during application and drying. Air from
the waterproofing operation is typically collected and exhausted to the atmosphere.
4-4
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a = exhaust fan
b = fugitive emissions from spray booth
c = flash off zone
d = fugitive emissions from drying oven
Figure 4-1. Rotary Spray Coating Booth and Drying Oven Showing
Emission Points.
4-5
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The emissions potential of the waterproofing process is high because of the
large amounts of organic solvent used to dispense the silicone material. Data
obtained from industry sources indicate that VOC emissions from waterproofing range
from 12.3 to 27.8 pounds of VOC per 1,000 square feet of leather processed.
4.1.3 Solvent Oegreasing
Solvent degreasing operations are used in a small segment of the industry in
the wet end processing of sheep and pig skins. In solvent degreasing, solvents such
as perch loroethylene are used to reduce the skin grease content to desired levels and
evenly distribute the residual grease prior to tanning. Emissions of VOC result
primarily from evaporation as the degreasing drums are drained and the skins
unloaded.
A study conducted in the United Kingdom generated emission estimates for the
degreasing operation. Measurements in the working area showed VOC
concentrations ranging from 600 to 700 mg/m 2. Measurements of exhaust air from
the degreasing system during the airing off cycle (draining and unloading of skins)
showed VOC concentrations ranging from 16,000 to 19,000 mg/m?5 Data provided
by the U. S. leather industry show emissions resulting from the degreasing operation
to be about 12.4 pounds of VOC per 1,000 square feet of leather processed.6
Typically, solvent degreasing operations are closed loop systems where the
solvent is recovered. Condensation recovery systems can reduce solvent loss by
about 90 percent compared to systems not having a recovery process. Carbon
adsorption systems are also used to recover solvent.7
4.1.4 Miscellaneous Fugitive Emissions
There are a number of sources of fugitive emissions in the leather tanning and
finishing industry. These sources include:
a) Mixing rooms - the mixing room used to formulate the various leather
coatings is a source of air emissions. Drums of coatings that are left
open can emit VOC and HAP emissions through volatilization of the
compounds. In addition, normal handling, pouring, pumping, and mixing
of the coatings can cause air emissions. Most leather finishing
operations use a designated room to mix finish coatings. One facility
estimates emissions from the mixing room to be about 10 tons per year,
representing less than 0.5 percent of the overall facility emissions.8
b) Coating drums - drums or other containers for the coating material" are
placed next to the spray booths or roll coaters during the finishing
process. The coatings are drawn from drums or other containers to the
4-6
-------
spray guns or rollers using vacuum pumps. These coating containers
can be a source of fugitive emissions since they are often partially or fully
open to room air. Emissions enter the atmosphere with the normal
building exhaust air.
c) Wastewater - wastewater can become contaminated with VOC and HAP
laden material in a number of locations throughout a tanning and
finishing plant. Water curtains and water baths are used for particulate
control and for catching overspray in the spray booths. Volatile organic
compounds present in the wastewater can be emitted when wastewater
is exposed to the ambient air in the collection and treatment system.
One facility has measured the organic content of the wastewater
generated by the plant. Total organic carbon (TOC) measurements were
less than 10 mg/L9
d) Cleanup operations - spray guns can be cleaned using solvents
containing VOC's. The emissions potential of spray gun cleaning
depends on whether the guns are cleaned in a closed container or an
open area.
e) Hand application of coatings - some finishing facilities apply coatings
using hand application procedures. An example of a hand application
operation is the antiquing process used to impart special effects on the
leather. Application of the coatings is usually conducted in an open
space. Fugitive emissions result from this operation due to volatilization
of the coatings during application. Emissions enter the atmosphere
through the building exhaust system.
f) Drying operations - leather that has been finished is set out to dry prior
to packing and shipping. Residual evaporation and volatilization of VOC
can occur during the drying process. Again, emissions of VOC can
enter the atmosphere through normal ventilation of the building air.
4.2 Factors Affecting VOC and HAP Emissions
There are both chemical and physical factors affecting emissions of VOC and
HAP from leather tanning and finishing. The primary factors affecting emissions are
the following:
a) The VOC and/or HAP content of the leather coating;
b) The physical properties of the individual VOC or HAP such as vapor
pressure and boiling point;
4-7
-------
c) The method of coating application (spray coating, roll coating, surface
coating, type of spray guns) as it affects transfer efficiency;
d) Operator training; and
e) Maintenance and housekeeping procedures.
The most important factor affecting emissions is the VOC/HAP content of the
coatings used to finish the leather. Significant reductions in emissions have been
reported through substitution of solvent coating systems with water based coatings. A
detailed discussion of the emission reductions achievable through the use of water-
based coatings is provided in Section 5.0.
There is very little quantitative data available to document the effects of most of
the other factors affecting emissions. Estimates have been made of the difference in
transfer efficiencies between spray coating systems and roll and flow coatings
systems. The transfer efficiency of roll and flow coating systems is close to 100
percent while efficiencies of spray coatings systems are estimated to be as low as 40
percent.
In regards to spray coating systems, there is also a wide range of estimates
regarding the effects of different types of spray guns on transfer efficiency. As will be
discussed in Section 5.0, the transfer efficiency of various spray guns can range from
15 to 90 percent. Accurate quantification of actual effectiveness of the various guns is
difficult because of the numerous factors that can effect transfer efficiency. Among
these factors are operator training and the solids content of the coating.
Other factors that can affect transfer efficiency of spray systems include the
type of spray controls used for the spray system (optical eye, pneumatic, or
mechanical controls), the number of spray guns, and the velocity of the rotary spray
arms and conveyor belt passing through the spray booth. One study indicates that
the use of optical eye spray controls can increase transfer efficiency by about 32
percent. x Conversations with industry personnel indicate that transfer efficiency is
affected by the number of spray guns operating on a rotary arm. The more spray
guns, the slower the rotor speed, and the greater the transfer efficiency. A 16-gun
rotary sprayer can be more efficient than an 8 or 4-gun machine.X1
Another factor in improving transfer efficiency is keeping the spray directed
vertically to the leather. Rotary spray machines that are rotating too fast can cause
the spray to "arc," creating a greater chance for bounceback. The speed of the
conveyor can also have a similar effect.
Adequate operator training can optimize the effectiveness of the coating
operation. A skilled operator can detect problems with spray guns, rotors speeds,
4-8
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and conveyor speeds. Timely identification of inefficiencies with the coating operation
can minimize the amount of coating used and, therefore, reduce emissions.
Finally, good maintenance and housekeeping practices can reduce emissions.
Examples of these practices include keeping containers of solvent closed, maintaining
spray equipment to optimize operation, and closely monitoring overspray and other
waste of material.
4.3 Volatile Organic Compound Emissions
Data were collected from a number of sources in order to quantify the potential
of leather tanning and finishing facilities to emit VOC. These sources include the
Aerometric Information Retrieval System (AIRS), State emission inventories and
permitting information, site visits, and information collected by the leather industry
trade association. Table 4-3 presents VOC emission factors for various facilities within
the industry.
The range of emission factors presented in the table is indicative of the diversity
within the industry. Emission potential varies from facility to facility depending on the
type of leather being manufactured. Emissions potential also varies among facilities
producing the same type of leather because of variations in the actual product mix and
the techniques used by each facility to meet the specifications of their customers.
Specialty operations such as waterproofing and solvent degreasing also increase the
emissions potential of individual facilities.
Appendix A includes all of the VOC emissions data collected during the study.
These data were obtained from EPA data bases, State and local agency inventories,
and permitting information. As shown in the Appendix, annual VOC emissions from
leather tanning and finishing facilities are extremely variable. A small facility may emit
less than 1 ton per year while larger facilities may emit in excess of 500 tons per year.
Table 4-4 shows the VOC emissions from a representative number of facilities.
4.4 Hazardous Air Pollutant Emissions
One of the objectives of this study was to quantify and characterize the
emissions of HAP's from the leather tanning and finishing industry. The CAAA require
EPA to publish a list of major and area sources for regulation that emit one or more of
the HAP's listed in Section 112(c) of the Act. A major source of HAP's is defined by
Section 112(a)(1) of the CAAA as being a source that "emits or has the potential to
emit considering controls, in the aggregate, 10 tons per year or more of any
hazardous air pollutant or 25 tons per year or more of any combination of hazardous
air pollutants."
4-9
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Table 4-3. Representative Emission Factors for
Leather Tanning and Finishing Facilities
TYPE OF FACILITY
Upholstery
Footwear
Upholstery
Upholstery
Waterproofed Leather
Sheepskin
EMISSION FACTOR
Ibs VOC/1000 sq. ft.
3.2-4.8
8.1 - 36.1
9.1
47.7
12.3 - 27.8*
12.4"
**
Represents emissions from waterproofing operation only.
Represents emissions from solvent degreasing operation only.
Source: Industry data. Identification of facilities withheld for proprietary purposes.
4-10
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Table 4-4. VOC Emissions from Representative
Leather Tanning and Finishing Facilities
FACILITY
Acme Sponge & Chamois
Horween Leather
Salem Suede
WD Byron & Sons
Prime Tanning
Lackawanna Leather (NC)
JBF Industries
Conneaut Leather
Garden State Tanning
Eagle Ottawa Leather
Seton Company (PA)
VOC EMISSIONS
(tons per year)
13.3
26.6
11.4
235.2
529.3
253.4
4.0
6.1
364.0
130.0*
120.0*
Note: Except as indicated, all data are for 1990. The source of the data is public
records obtained from State agencies or other sources.
* 1992 estimated data provided by the facilities.
4-11
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The most comprehensive data available for determining industry-wide HAP
emissions is found in the TRI. For the leather tanning and finishing industry, the TRI
data can be considered relatively accurate information. In most cases, the emissions
data reported to TRI are based on solvent purchases and usage. A material balance
approach is the most common method of determining emissions of HAP's. Assuming
that the record-keeping practices of the facilities reporting to TRI are reliable, the TRI
data provide a reasonably accurate summary of HAP air emissions from the industry.
Seventeen major sources of HAP's have been identified in the industry.
Table 4-4 lists the major sources or HAP's. It is estimated that the actual number of
major sources existing in 1993 is less than 17. The trend in the industry is to convert
to water-based coatings in the leather finishing process and to reformulate coatings to
eliminate hazardous constituents. The emphasis on water-based materials began in
1989, and many of the reductions achieved by the transition are not reflected in the
1990 TRI data. Information obtained during site visits, telephone conversations, and
through review of current literature indicates that HAP emissions are being reduced
industry wide.
Rgure 4-3 shows the trends in nationwide HAP emissions from 1987 to 1990.
The upper line in the graph represents data from all facilities reporting to TRI in each
year (33 facilities). The lower line represents data for only those facilities that reported
emissions in each of the four years from 1987 to 1990 (23 facilities). Although the
upper line shows a substantial increase in HAP emissions nationwide, it is primarily the
result of more facilities reporting to the data base. The lower line is more indicative of
the actual trend in emissions production since it represents data for a fixed set of
facilities.
4-12
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8.0-1
5.0
1987
1988 1989
Reporting Year
All Facilities Reporting to TRI
1990
&&£) Facilities that Reported Emissions in Each of the Four Years
Figure 4-3. Trends in Nationwide HAP Emissions for All Reporting Facilities
(1987-1990) and Facilities Reporting for All Fours Years.
4-14
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4.5 References
1. Corning, D.R., NJ. Cory, S.W Nott, and R.L Sykes. The Impact of Air Pollution
Controls on Tannery Operations. Journal of the Society of Leather Technologists
and Chemists. Volume 75, p. 183. 1991.
2. Trip Report. Mitsch, B.F and Howie, R. H., Alpha-Gamma Technologies, Inc. to
Iliam Rosario, Industrial Studies Branch, Office of Air Quality Planning and
Standards, U. S. EPA. April 7, 1993. Final trip report of visit to Seton Company,
Saxton, PA, on January 7, 1993.
3. Trip Report. Mitsch, B.F. and Howie, R.H., Alpha-Gamma Technologies, Inc. to
Iliam Rosario, Industrial Studies Branch, Office of Air Quality Planning and
Standards, U. S. EPA. April 6, 1993. Final trip report of visit to Mercersburg
Tanning, Mercersburg, PA, on January 8, 1993.
4. Letter from Rutland, F.H., Leather Industries of America, Inc. to Mitsch, B.F.,
Alpha-Gamma Technologies, Inc. February 24,1993. Letter providing emissions
data collected by the leather industry.
5. Reference 1.
6.
7.
8.
9.
Reference 4.
Reference 5.
Reference 2.
Reference 3.
10. Stockman, George. "Determination of Spray Machine Transfer Efficiency for
Leather Finishing." Journal of the American Leather Chemists Association, Volume
83. 1988.
11. Reference 2.
4-15
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5.0 EMISSION REDUCTION AND CONTROL TECHNIQUES
This section provides a discussion of the options available to reduce and
control VOC and HAP emissions from leather tanning and finishing operations. These
options originate from a wide variety of sources including State and local regulatory
agency documents, EPA documents, emission inventories and surveys, and visits to
several leather processing facilities.
Under the Pollution Prevention Act, it is national policy that pollution be
prevented or reduced at the source whenever feasible. Where pollution cannot be
prevented, it should be recycled in an environmentally safe manner. In the absence of
feasible prevention and recycling opportunities, pollution should be treated.
Collectively, this technique of pollution prevention is called life cycle assessment, or
cradle-to-grave analysis. This is certainly the strategy that should be employed in
reducing emissions from leather tanning operations.
This section includes a presentation of source reduction technologies as well as
treatment technologies. Source reduction techniques available to leather finishing
operations and the associated emission reductions tend to be very site-specific. For
this reason, the more universally applicable treatment technologies are discussed first.
Control technologies are discussed in Section 5.1 and emission reduction technologies
are discussed in Section 5.2.
5.1 Emission Control Techniques
This subsection provides a description of various abatement control
technologies applicable to VOC and gaseous HAP emissions from leather finishing
operations. This discussion includes generally applicable technologies applied in
similar industries, as well as those present in the leather finishing industry. The only
known abatement devices currently employed within the domestic leather finishing
industry are regenerative thermal incinerators which are presently operated at two
facilities. Both of these facilities were visited as part of this study, and this section
incudes a presentation of performance data obtained from these sites.
As discussed in Section 4.0, the bulk of emissions resulting from leather '
finishing operations are from the spray booth and the associated dryer. There is little
data available-to quantify what portion of total emissions occur between the spray
booth and the exit of the associated dryer. As discussed in Section 4.0, other points
5-1
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of emission are the mixing room, fugitive emissions associated with supplying coatings
to the spray guns (often includes open drums of virgin material), clean up operations,
secondary emissions from the contaminated water wash, and solvent evaporation after
the drying operation. The most significant of these sources is likely to be emissions
associated with clean up, and most of these emissions can be captured by operating
the spray booth exhaust during gun cleaning. Since the bulk of emissions occur
between spray application and drying, this is the portion of the leather finishing
operation where abatement control technologies are most applicable.
»
Effective overall control of VOC and HAP emissions requires both the effective
capture-of emissions and the effective removal or destruction of the VOC and HAP.
The overall control efficiency is the product of capture efficiency of the system and the
control device removal or destruction efficiency. The EPA has established a total
enclosure as the highest level of capture, and the capture efficiency of a structure
meeting EPA's criteria for a total enclosure is deemed to be 100 percent. The
applicability of total enclosures to leather finishing operations is discussed in
Section 5.1.1. It is generally recognized that air pollution control devices such as
thermal incinerators, catalytic incinerators, and carbon adsorbers are capable of
providing control efficiencies of greater than 95 percent for VOC and gaseous HAP. A
description of these devices and their respective control efficiencies is provided in
Section 5.1.2
Although control cost analysis is beyond the scope of this document, it is
important to note that there is also an economic component of effective capture.
Exhausts from spray booths and dryers are generally high volume streams with dilute
VOC concentrations. Methods to reduce the exhaust volume should be evaluated
prior to determining the required size of the control device. Methods for reducing the
volume of spray booth and dryer exhausts are discussed in Section 5.1.3
5.1.1 Total Enclosure for Effective Capture of VOC and Gaseous HAP
The first element of effective abatement control is the effective capture of
emissions. As indicated above, the capture efficiency is considered to be 100 percent,
if the source of VOC is totally enclosed (e.g., meets the EPA criteria for a total
enclosure). A total enclosure is a structure that completely surrounds a source of
emission such that all VOC emissions exhaust through a duct to a control device. The
EPA has established the following criteria for verifying that an enclosure is a total
enclosure:1
a) Any natural draft opening (NDO) is at least 4 equivalent opening
diameters from each VOC emitting point. An NDO is defined as any
permanent opening in the enclosure that remains open during operation
of the facility and is not connected to a duct in which a fan is installed.
5-2
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b) The total area of all NDO's does not exceed 5 percent of the surface
area of the enclosure's four walls, floor, and ceiling.
c) The average facial velocity (FV) of air through all NDO's is at least 3,600
meters per hour (200 ft/min). The direction of air through all NDO's is
into the enclosure.
d) All access doors and windows whose areas are not included in number 3
are closed during routine operation of the process.
Procedures for determining NDO's and FV are provided in the Method and in
the EPA enabling document, The Measurement Solution, Using a Temporary Total
Enclosure for Capture Efficiency Testing.2
A total enclosure may be set up over an individual booth or oven, or over an
entire finishing line. Alternatively, an entire finishing room may function as a total
enclosure.
Establishing a total enclosure over an entire finishing line is achievable on
automated spray finishing lines. In fact, one of the leather finishing facilities currently
equipped with a regenerative thermal incinerator has demonstrated a total enclosure
for the controlled lines.3 In this case, the new lines were installed with an enclosure
over the entire line. NDO's are located at the front of each spray booth and at the exit
of each dryer where the hides enter and exit the line. These openings are narrow
slots 5 to 7 inches high and about 76 inches long. In addition, each spray booth is
equipped with one NDO about 30 inches by 60 inches to provide access to the spray
guns. This opening is covered with a heavy, plastic curtain. The curtain has small
openings that represent less than 0.5 ft2 of total opening. The total area of all NDO's
on each of two lines are 1 percent or less of the total area of the enclosure. For
determination of equivalent opening diameters, the center of the rotary spray wheel in
each booth was considered the VOC emitting point.
Establishing a total enclosure over an entire line may not be practical in some
retrofit situations. But, much of the necessary enclosure naturally exists in automated
leather finishing operations. The most common spray equipment in medium and
larger operations is fully or partially enclosed rotary spray booths. These systems are
more fully described in Section 4.0. Following application of the coating in a rotary
spray booth, the leather travels on a mechanical conveyor through a flash off area and
on to a heated drying oven. Emissions captured by the spray booths and dryers are
already exhausted through ducts for protection of the workers.
In manual or hand spray operations, establishing a total enclosure over
individual finishing lines is much more difficult. In these situations, an entire finishing
room could function as a total enclosure. All booths and ovens could be exhausted to
5-3
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a VOC control device with no other exhaust points from the room. The room would
have to be maintained at a slight negative pressure. In this case, any open doors or
widows would be considered NDO's.
5.1.2 Control Devices
This subsection provides a description of three types of add-on control
technologies applicable to the control of VOC and gaseous HAP emissions from
leather finishing operations. These are thermal incineration, catalytic incineration, and
carbon adsorption.
AS indicated above, the only known add-on control technology currently-
employed within the leather tanning and finishing industry is regenerative thermal
incineration. This control technology was installed at two new leather finishing facilities
and both were visited as part of this CTC effort. Case study accounts of the findings
at each of these leather finishing facilities are provided in Appendix B. Information on
the operation and performance of these systems is included below in the discussion of
regenerative thermal incineration.
5.1.2.1 Thermal Incineration
Thermal incineration is a process by which waste gas is brought to adequate
temperature, and held at that temperature for a sufficient residence time with sufficient
oxygen for the organic compounds in the waste gas to oxidize. Since the compounds
emitted from leather finishing operations are generally hydrocarbons consisting of
carbon and hydrogen, the products of thermal oxidation are carbon dioxide and water
vapor. Based on performance tests conducted at leather finishing facilities, VOC
destruction efficiencies of greater than 98 percent can be achieved for emissions from
leather finishing operations.4'5 In addition, EPA studies indicate that a well designed
and operated commercial incinerator can achieve at least 98 percent destruction
efficiency (or an outlet concentration of 20 ppm or less) of organics. This destruction
efficiency corresponds to incinerators that are operated at 1600T with a nominal
residence time of 0.75 seconds.8
A schematic diagram of a typical thermal incineration unit-is provided in
Figure 5-1. Primary components of the thermal incineration unit include a fan, a heat
recovery device, the combustion chamber, and the exhaust stack. The heat recovery
device is used to preheat the incoming waste stream so that less auxiliary fuel is
required in the combustion chamber. This type of heat recovery is known as primary
heat recovery and can be further categorized as either recuperative or regenerative.
The waste gas preheater shown in Figure 5-1 would be referred to as a recuperative
heat exchanger. As shown in this figure, a heat exchanger is used to transfer heat
from the hot incinerator exhaust stream to the incoming waste stream. This is a
continuous steady state process. Types of heat exchangers typically used for
5-4
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recuperative heat recovery include plate-to-plate and shell-and-tube. Recuperative
heat recovery can provide up to 70 percent recovery of the heat in the exhaust
stream, thereby reducing fuel use, the primary operating cost, by up to 70 percent.
Regenerative heat recovery is accomplished by cycling the incinerator exhaust
gas through a ceramic bed. An incinerator employing regenerative heat recovery is
presented in Figure 5-2. As indicated in the figure, the waste gas stream first passes
through a hot ceramic bed, thereby heating the waste stream. The ceramic bed in
turn, is cooled. The heated waste stream is introduced into the combustion chamber
where it is combusted, thus releasing energy. The exhaust from the combustion
chamber is then routed through another ceramic bed, heating the ceramic material in
the bed. When the ceramic bed reaches the desired temperature, the process flows
are then switched, and the waste gas flow is fed to the hot ceramic bed.
Regenerative heat recovery systems can recover up to 95 percent of the energy in the
incinerator exhaust gas, with a comparable reduction in fuel, the major operating
expense.78
The choice of thermal incineration with regenerative versus recuperative heat
recovery or no heat recovery is driven by economics. Regenerative heat recovery
represents substantially more capital cost, but offers the long-term savings of reduced
auxiliary fuel costs.
As indicated above, two leather finishing facilities currently operate regenerative
thermal incinerators for the control of VOC emissions. Both sites were visited as part
of this study to observe and discuss the operation of these VOC control devices. The
design and operating characteristics of each unit are presented in Table 5-1. The
VOC destruction efficiency of each unit has been demonstrated to be greater than 98
percent using EPA Methods. The results of these tests are also presented in
Table 5-1. As indicated in the table, the unit located at Plant A is designed to provide
control of VOC emissions from three eight-gun rotary spray booths and the three
associated dryers. The rated capacity of this unit is 30,000 cfm and the reported
capital cost is $1.5 million (1989)." The unit located at Plant B is designed to provide
control of VOC emissions from two sixteen-gun rotary spray booths and the two
associated dryers. The rated capacity of this unit is 24,000 cfm and the reported
capital cost is $800,000 (1989).10
At Plant B, operation of the associated leather finishing line is two 8-hour shifts,
seven days per week. Additionally, the flow to the incinerator varies periodically from
0 cfm to 12,000 cfm (one booth) to 24,000 cfm (two booths). Based on discussions
with plant personnel, the regenerative thermal incineration system is able to handle this
wide variation with ease. At the end of the second shift, the incinerator is set to go
through a 3-hour cool down where the combustion chamber temperature drops from
1500°F to SOOT. To minimize operating cost, the combustion chamber temperature is
maintained at 500°F during the idle period (when the spray booths are not being
5-6
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Table 5-1. Design and Operating Characteristics of Existing
Regenerative Thermal Incinerators
Design Flow Rate (cfm)
Combustion Temperature (°F)
Inlet Concentration (ppmv)"
VOC Destruction Efficiency (%)
Reported Capital Cost (1989$)
Sources Controlled
Plant A
30,000
1,450
660
99.5b
1,500,000
3 - Spray Booths
Plant B
24,000
1,500
1,540
98.6b
800,000
2 - Spray Booths
Reported Capture Efficiency
of Collection System
2 - Catalytic Dryers
1 - Steam Heated Dryer
100C
2 - Dryers
9V
* As propane.
b Based on perfromance test using EPA Method 25A on inlet and outlet of thermal
incinerator.
c Based on the criteria for a total enclosure.
d Based on a material balance using coating consumption rate, coating VOC content,
and Method 2A/25A measurements. The accuracy of such determinations is
suspect.
5-8
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operated). Then prior to the start of the first shift, the incinerator is set to go through
a three-hour warm up, where the combustion chamber temperature is raised from
500°F to 1500°F. When both booths are operating, operation of the thermal
incinerator is self-sustaining, i.e., there is no auxiliary fuel requirement.11
Both of the existing thermal incinerator systems were installed on new leather
finishing facilities. Plant B was an entirely new facility that began operation in 1989. At
Plant A, a new finishing facility was added on to an existing plant. Installation of the
thermal incinerator systems are considered lowest achievable emission rate (LAER)
technology. Retrofitting this technology on an existing finishing facility may be more
difficult and expensive than for a new facility.
5.1.2.2 Catalytic Incineration
Catalytic incineration is similar to thermal incineration in that VOC's are heated
to a temperature sufficient for oxidation to occur. However, with catalytic incineration,
the temperature required for oxidation is considerably lower than that required for
thermal oxidation because a catalyst is used to promote oxidation of the contaminants.
The catalyst is imposed on a large surface containing many active sites on which the
catalytic reaction occurs. Platinum is the most widely used catalyst while palladium is
also commonly used.12 Because these metals are expensive, only a thin film is
applied to the supporting substrate. A commonly used substrate is ceramic.
A well designed and operated catalytic incineration unit can achieve destruction
efficiencies of 98 percent, comparable to thermal incineration units. However, the
destruction efficiency decreases in the presence of catalyst poisons and
particulates.13
The catalyst bed in catalytic incinerators generally operates at temperatures
ranging between 300°F and 900°F, with temperatures rarely exceeding 1000°F. The
contact time required between the contaminant and the catalyst, so that complete
oxidation occurs, is normally 0.3 seconds. The excess air requirements for catalytic
incineration units are only 1 to 2 percent higher than the stoichiometric
requirements.1415 Catalytic incinerators can be designed to control waste gas flow
rates up to about 50,000 ft3/min. The VOC content of the waste stream may be in the
part per million range up to 25 percent of the lower explosive limit (LEL).
A schematic of a typical catalytic incineration system is presented in Figure 5-3.
As indicated in this figure, components of the system include a fan, a preheat burner,
a combustion chamber, a waste gas preheater (recuperative), a secondary heat
recovery, and a stack. The preheat burner is used to heat the incoming waste stream
to the required oxidation temperature, usually between 300°F and 900°F for catalytic
incineration.16 The catalyst bed may be a fixed-bed or a fluidized bed consisting of
individual pellets enclosed in a screened unit. The recuperative heat recovery device,
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if included, is a shell-in-tube or plate-to-plate heat exchanger. Recuperative heat
recovery is incorporated if supplemental fuel requirements are expected to be high.
Many factors affect the performance of a catalytic incineration system. The
primary factors include operating temperature, space velocity (inverse of residence
time), VOC concentration and species, and catalyst type and susceptibility to
contaminants. The optimum operating temperature is dependent on the type of
catalyst, as well as the concentration and type of VOC's. Space velocity is defined as
the volume of the gas entering the catalyst bed divided by the volume of the catalyst
bed. Space velocity is very dependent on operating temperature. However, in
general, as space velocity increases, destruction efficiency decreases. The amount
and type of VOC determine the heating value of the waste stream, and thus the -
amount of supplemental fuel required to maintain the desired operating temperature.17
The type of catalyst selected is based on the VOC compounds in the waste
stream. Particulates and catalyst poisons in the waste stream can affect the efficiency
of the catalyst, and its lifetime. Some materials that are considered catalyst poisons
include heavy metals (mercury, lead, iron, etc.), silicon, sulfur, halogens, organic
solids, and inert particulates. Particulates and poisons reduce the activity of the
catalyst site, minimizing sites available for the oxidation reaction. These materials can
also mask, plug, or coat the catalyst surface.18
5.1.2.3 Carbon Adsorption
Carbon adsorption recovery efficiencies of 95 percent and greater have been
demonstrated to be achievable in well designed and well operated units.192tt21'22
Fixed bed carbon adsorption units have been sized to handle flow rates ranging from
several hundred to several hundred thousand ft'/min. There is no obvious practical
limit to flow rate because multi-bed systems operate with multiple beds in simultaneous
adsorption cycles. The VOC concentrations of the waste streams controlled by
carbon adsorption units can range from the part per billion level to as high as 20
percent of the LEL Adsorption systems typically operate at ambient pressure and
temperatures ranging between 77 and 104°F.23
The carbon adsorption process used to control VOC emissions from waste gas
streams can be divided into two sequential processes. The first process involves the
adsorption cycle, in which the waste gas stream is passed over the adsorbent bed for
contaminant removal. The second process involves regeneration of the adsorbent
bed, in which contaminants are removed using steam or hot gas, so that the carbon
can be reused for contaminant removal.
Adsorption is the capture and retention of a contaminant (adsorbate) from the
gas phase by an adsorbing solid (adsorbent). Activated carbon is the most widely
used adsorbent for air pollution control.24 Both the internal and external surfaces of
5-11
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the carbon are used as adsorption sites. Diffusion mechanisms control the transfer of
the adsorbate from the gas phase to the external surface of the carbon, from the
external surface of the carbon to internal pores, and finally to an active site in the
pores. Adsorption depends on a mass transfer gradient from the gas phase to the
surface. Van der Waal forces attract the adsorbate to the carbon. Because
adsorption is an exothermic process, some method of heat removal from the carbon
may be necessary, depending on the amount of contaminant being removed from the
gas phase.29
Regeneration is the process of desorbing the contaminants from the carbon.
Regeneration of the carbon bed is usually initiated prior to breakthrough.
Breakthrough is that point in the adsorption cycle when the carbon bed approaches
saturation and the concentration of organics in the effluent stream begins to increase
dramatically. If the carbon bed is not regenerated, the concentration of VOC's in the
effluent will continue to increase until it is equal to that of the inlet, i.e., the carbon is
saturated.29 The most common method of regeneration is through steam stripping.
Another regeneration method is the use of hot, inert gas or hot air. With either steam
or hot air regeneration, the desorbing agent flows through the bed in the direction
opposite to the waste stream. This desorption scheme allows the exit end of the
carbon to remain contaminant free.27
In a regeneration process, some adsorbate, known as the heel, may remain in
the carbon after regeneration. The actual capacity of the carbon is referred to as the
working capacity, and is equal to the total capacity of the carbon less the capacity
taken by the heel.28
Adsorption units that are commonly used for contaminant removal from waste
gas streams include:
a) Fixed, or rotating, regenerable carbon beds;
b) Disposable/rechargeable carbon beds;
c) Traveling bed carbon adsorbers;
d) Fluid bed carbon adsorbers; and
e) Chromatographic baghouses.
Of the five adsorption systems listed above, the first two are most commonly
used for air pollution control. The disposable/rechargeable canisters are used for
controlling low flow rates (less than 100 cubic feet per minute) and would not be used
to control the high volume flow rates typical of leather finishing operations. Only the
fixed bed, regenerable carbon adsorption system is discussed in this section.
A fixed bed, regenerable carbon adsorption system is presented in Figure 5-4.
The components of the carbon adsorption system include (1) a fan (to convey the
waste gas into the carbon beds), at least (2) two fixed-bed carbon adsorption vessels,
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(3) a stack for the treated waste gas outlet, (4) a steam valve for introduction of
desorbing steam, (5) a condenser for the steam/contaminant desorbed stream, and
(6) a decanter for separation of the VOC condensate and water. In the system
depicted in Rgure 5-4, one carbon vessel is being used for adsorption while the other
is being regenerated. Both vessels will alternate in the adsorption and regeneration
modes. The steam is used to regenerate a vessel, and is then sent to a condenser.
The condensate is a water/VOC mixture. The decanter can be used to separate the
condensate into a water stream and a condensate stream. Depending on its
measured toxicity, the water may be treated or discharged to the sewer. The
condensed organics can be recycled (if usable), used as a fuel, or disposed.
Several factors affect the amount of material that can be adsorbed onto the
carbon bed. These factors include type and concentration of contaminants in the
waste gas, system temperature, system pressure, humidity of waste gas, and
residence time.29
5.1.3 Methods of Minimizing Control Costs -- Volume Reduction
Exhaust streams from leather finishing operations are generally high volume,
dilute concentration, streams. To minimize the size and cost of the abatement control
device, volume reduction measures should be evaluated. Such a volume reduction
can provide several economic benefits including: (a) reduced air flow to the add-on
device reducing capital costs; (b) a more concentrated stream for treatment reducing
capital and operating costs of the add-on control device; and (c) reduced makeup air
reducing plant heating and cooling costs.
The first volume reduction measure that should be considered is recirculation of
booth and dryer exhausts. Recirculation of booth and/or dryer exhausts could
provide substantial volume reduction of the abatement stream. The amount of air that
can be recirculated is limited by the maximum VOC concentration allowed in the booth
or dryer. In automatic spray booths such as the rotary spray booths used in the
leather finishing industry, insurance companies usually require that the VOC
concentration in the booth be less than 25 percent of the LEL The same is true for
dryers. Additionally, the National Fire Protection Association (NFPA) requires an LEL
monitor if the VOC concentration is expected to exceed 20 percent of the LEL30
Recirculation is much easier to address in the case of a new installation since it
may require substantial modification of the spray booth and dryer design. But
considering the potential economic benefits, recirculation should be evaluated in
retrofit applications as well as new installations.
Whether or not recirculation is currently used at leather finishing facilities is not
known. However, recirculation has been used in both manual spray booths and
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mechanical spray booths in other industries which are similar to those used in the
leather finishing industry.31 In addition, studies have also been conducted by EPA to
ascertain the feasibility and safety of recirculation.3*33 Those studies conclude that
recirculation can safely and effectively be used in spray booths.
There are also several emerging technologies specifically targeted at reducing
the volume of air that must be exhausted through manual spray booths. Since a side
draft velocity of 100 ft/min must be maintained across the worker to meet OSHA
requirements, the potential reductions in air volume are limited, without completely
changing the design of manual spray booths. Two emerging technologies that show
great promise for reducing the volume of air that must be exhausted, while maintaining
an adequate level of operator protection, are the Classic Systems Campbell Spray
Booth and the Mobile Zone system.
Classic Systems indicates that its Campbell Spray Booth can reduce the volume
of exhaust air by approximately 80 percent.34 The basic design of this spray booth
involves the use of air curtains. The worker stands outside of the booth and sprays
through the air curtain. The air curtain provides a barrier between the worker and the
solvent emissions inside the booth, resulting from spraying the coating. The booth
design can also include an adjacent, enclosed flash tunnel. As with the spray booth,
air curtains separate the air inside the flash area from the outside air. The design is
such that the exhaust from the flash tunnel can be recirculated back to the spray
booth. By incorporating this recirculation, makeup air requirements are further
reduced.
Mobile Zone Associates has developed a device that enables the worker to
spray coatings from a partially enclosed mobile work platform.35 The worker stands
inside of a moving cab. The movement of this cab is controlled by the worker. Within
the Mobile Zone cab, fresh ventilating air passes across the worker from an open
moving window at his rear. The remaining section of the mobile work platform is
ventilated using recirculated air. The Mobile Zone design contrasts with a conventional
spray booth, in which the entire length of the booth is supplied with fresh ventilating
air. Through the use of the moving window, the ventilating air requirements for the
worker are greatly reduced. In one EPA sponsored test of this system in a paint spray
operation, the Mobile Zone design allowed a 90 percent reduction in the spray booth
exhaust rate.39
5.2 Emission Reduction Techniques
The largest source of VOC and HAP emissions from the leather tanning and
finishing industry is the finishing operation. Because of the disproportional impact
finishing operations have on emissions, they are the primary focus for emission
reduction measures. Efforts to reduce emissions from leather finishing can be
categorized by: a) use of lower VOC or water-based coatings; b) improved transfer
5-15
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efficiency of the coatings application process; and c) improved housekeeping
practices and employee training.
5.2.1 Use of Lower VOC and Water-Based Coatings
As discussed in Section 3.0, coating formulations can be classified by VOC
content. These classifications include lacquers, lacquer emulsions, and water-based
coatings. Table 5-2 illustrates the differences in VOC content among these coating
classifications. In addition to reduced VOC content, water-based coatings have higher
solids-carrying capabilities, which usually translates to reduced volumes of coatings
needed to finish the leather.
The leather industry has made progress in the use of lower VOC coatings over
the past few years. This trend has been hastened by increased pressure to lower
VOC emissions to meet State and local air quality regulations. In addition, the leather
industry recognizes there are several other benefits to using lower VOC coatings.
These benefits include improved working conditions and employee safety, reduced
costs in treating and disposing of hazardous wastes, and, improvement in local public
relations. The potential exists for water-based coatings to be used in all finishing coats
with subsequent reductions in VOC emissions.
From discussions with major coating suppliers, there are indications that many
leather manufacturers are converting to water-based coatings.37 As presented in
Table 3-3, one chemical supplier has seen a shift from solvent-based coatings to lower
VOC coatings in it's top ten selling products to leather finishers. It should be noted
that although the predominant formulations may be water-based, some applications
will require the addition of penetrator and leveling agents which contain VOC's. Still,
the shift to lower VOC coatings is apparent.
The VOC reductions achieved by switching to water-based coatings can be
dramatic. For example, one facility that was able to fully convert from solvent coatings
to water-based coatings reduced VOC and HAP emissions by 95 percent.38 The use
of water-based coatings still presents numerous difficulties to the leather finisher, but
most of these difficulties have been overcome with regards to base and intermediate
coatings. In fact, water-based coatings are now typical for base and intermediate
coats in much of the industry. However, the use of water-based coatings is still
difficult in other applications, particularly the top coats. Situations that can prevent the
conversion to low VOC coatings include:
a) The conversion to water-based coatings can require substantial research
and development efforts. The conversion process is generally not as
simple as substituting a water-based coating for a solvent coating.
Changes must often be made in the retannage and fatliquoring process
to ensure compatibility of the leather with the coatings;
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Table 5-2. Comparison of Lacquer, Lacquer-Emulsion and Water-Based
Top Coat Systems
Property
Application
Solids (%)
Wt.% Solvent
(as applied)
VOC (#/gal. less
water supplied)
Gallons to Finish
100 Sides
Pounds Organic
Lacquers
5-15
75-95
5.0-6.5
9
46.4-61.8
Lacquer
Emulsions
5-20
40-60
5.0-6.5
7
22.8-30.9
Water-Based
Coatings
20-30+
5-15
0-3.0
4.5
0-4.0
Solvent Emitted per
100 Sides
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b) In situations where the look and feel of the leather are key
characteristics, it may be impossible to produce the required esthetics
that customers demand with water-based coatings; and
c) In shoe leather, additional coatings are applied to the leather by the shoe
manufacturers. As a result, finishes applied by the leather finisher must
be compatible with the finishes applied by the shoe manufacturer.
5.2.2 Emission Reductions From Improved Transfer Efficiency
Several advances have been made in the application techniques used for
leather finishing operations. These advances include the use of higher efficiency spray
guns, use of optically controlled spray guns, and use of alternative application
techniques such as roll coating. In addition, the potential for using radiation to cure
top coats is also being explored by the industry. A discussion of the emissions
reduction potential offered by each of these technologies is provided below.
5.2.2.1 High Efficiency Spray Guns
In all spray coating operations, some coating solids either miss or bounce off
the material thereby reducing the transfer efficiency of the spray system. Transfer
efficiency is the ratio of the solids that adhere to the material divided by the solids
directed, or sprayed, at the material. Conventional spray systems have low transfer
efficiencies ranging from 10 to 30 percent. These low transfer efficiencies are
attributed to excessive bounce-back and overspray. Bounce-back is that portion of
the finish coating which impinges on the leather surface but does not stick. Overspray
can be defined as the portion of the spray pattern which falls outside the area of the
material coated. The resulting loss in solvents and coating material can be in excess
of 75 percent.
Bounce-back and overspray are problems generally associated with spray
guns. The various spray guns used to finish leather differ in the manner in which they
break up (atomize) the coating. Some methods are associated with inherently better
transfer efficiencies than others as shown in Table 5-3. However, these transfer
efficiencies are only estimates and are dependent on many other factors which are
discussed below. Spray guns can be divided into several basic types including:
a) Conventional air sprav - Conventional air spray has been the traditional
method of applying coatings. Compressed air is supplied through an air
hose to a spray gun that atomizes the paint into a fine spray. The
pressure supplied to the fluid controls the paint delivery rate with typical
pressures ranging form 5 to 25 pounds per square inch (psi). The air
pressure controls the degree of atomization and is usually 30 to 90 psi.
One of the major problems with conventional air spray is the bounce-
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Table 5-3. Transfer Efficiencies of Different Spray Techniques"
Product Type Transfer Efficiencies**
(in percent),
Conventional Air Spray 15-30
Airless Spray 20-40
Air Assisted Airless Spray 25-45
Electrostatic Air Assisted Airless 55-85***
High Volume Low Pressure Spray 55-90
* Based on manufacturer claims for various spray equipment products.
Transfer efficiency is defined as the net amount of coating solids deposited on a part,
divided by the total coating solids sprayed, and expressed as a percentage:
**
***
Where:
TE = Transfer Efficiency
We = Weight of coating solids added to material, after drying
%S = Percent of coating sprayed that is solids
Q = Coating Flow Rate, weight per time unit
T = Time coating is flowing
Electrostatic modifications to spray equipment is not considered effective for leather
finishing operations.
5-19
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back and overspray caused by the high volume of air required to achieve
. atomization. This results in relatively poor transfer efficiency.
b) Airless sorav - With airless spray, a pump forces the coating through an
atomizing nozzle at high pressure (1,000 to 6,000 psi) instead of using
compressed air to atomize the material. Due to its high pressure, airless
spray is ideal for rapid coverage of large areas and when a heavy film
build is required. The size of airless spray droplets are larger, the spray
cloud is less turbulent, and the transfer efficiency is typically superior to
conventional air spray. However, airless spray leaves a rougher, more
textured surface and is generally used when appearance is not critical.
c) Air-assisted airless sprav - An air-assisted airless system combines the
benefits of conventional air spray and airless spray. The system consists
of an airless spray gun with a compressed air jet to atomize the coating.
These systems use lower fluid pressures than airless spray and lower air
pressures than conventional air spray (5 to 20 psi versus 30 to 90 psi).
This fluid/air pressure combination delivers a less turbulent spray than
conventional air systems and applies a more uniform finish than airless
systems. However, due to the lower air pressure, the amount of time
needed to apply the coating is greater when using the air-assisted airless
system.
d) High Volume Low Pressure Spray - A modification of conventional air
spray is high volume low pressure (HVLP) spray which uses large
volumes of air under reduced pressure (10 or less psi) to atomize the
coatings. Because of the lower air pressure, the atomized spray is
released from the gun at a lower velocity. Overspray has been reported
to be reduced 25 to 50 percent over conventional air spray. The air
source for the HVLP can be a turbine or a standard air supply, both of
which can handle multiple spray guns. Manufacturers have constructed
fluid passages out of stainless steel or plastic so that these guns are
compatible with a full range of solvents and water-based materials. Many
of the HVLP spray systems are designed to atomize high, medium, or
low solids coatings.
Some states have mandated that all coating operations be converted to use
more efficient spray equipment.39 However, as stated in other previous EPA studies
on surface coating, the degree of increased transfer efficiency is dependent on many
factors.40 These include coating characteristics, types of spray equipment, types of
spray booths, and operator training. While the actual transfer efficiency values may be
controversial, it is generally accepted that switching to HVLP or other current-
generation spray systems will reduce coating usage. This in turn leads to reductions
in the use of VOC laden solvents and subsequent reductions in VOC emissions.
5-20
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5.2.2.2 Optical Eye/Microprocessor Controls on Spray Equipment
All of the spray guns described above can be attached to automated machines.
These machines range from horizontal reciprocating machines which maneuver the
spray guns back and forth, to the more common rotary spray machines which rotate
between four and sixteen spray guns over the surface to be coated. Either type of
spray system has the potential for a large amount of overspray resulting in VOC and
HAP emissions.
Because of this inefficiency, microprocessor controls coupled with electronic
eyes are being used in tandem with the various spray machines. The efficiency of this
equipment was tested in one experiment where a copper-containing pigment was
sprayed on leather as the topcoat using equipment with and without microprocessor
controls. As Table 5-4 shows, the use of microprocessor controls improved the net
transfer efficiency of copper by 66 percent.41
Because of their relative low-cost, the return-on-investment in these systems
can be realized within the first year.4*43 Recent industry surveys indicate that various
forms of this technology are used in over 70 percent of the leather finishing facilities
using automated spray equipment.44
5.2.3 Housekeeping Practices
In addition to the emission reduction techniques mentioned above, VOC
emissions can be minimized through diligent housekeeping practices. For example,
fugitive emissions can be minimized by storing fresh and spent solvents in containers
designed to minimize evaporative losses. Coating waste can be minimized by mixing
only as much coating as is needed to complete finishing jobs. Cleaning solvents
should be used in enclosures and systems which minimize the volume needed and
evaporation. And waste coatings, spent solvents, and sludge from gun cleaners and
in-house distillation units should be disposed of properly by transfer to designated
hazardous waste management facilities. Implementation of in-house training programs
can provide workers with guidance regarding practices that can reduce emissions.
5.2.4 Degreasing Operations
Sheep skin and pigskin tanneries often use solvent degreasing operations in the
leather manufacturing process. The hides of these animals contain high quantities of
inter-fiber fat that must be removed prior to tanning. Solvent degreasing
involvesplacing the hides in drums containing solvents such as trichloroethylene or
perchloroethylene, along with surfactants.49 Solvent recovery systems are usually used
when hydrocarbons or solvents are used for degreasing. However, a substantial
amount of solvent can be lost from the system because of inefficient condensation or
by diffuse evaporation as skins are drained or inspected.
5-21
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Table 5-4. Demonstration of Increased Transfer Efficiency Using
Optical Eye Spray Control Systems.
Without Controls With Controls
Total Cu Offered (10 Sides)
Net Cu Taken Up (10 Sides)
Transfer Efficiency
3.24 g
0.872 g
26.9%
2.46 g
1.098g
44.6%
Note: Copper (Cu) is a trace metal in the. dye used to study the transfer efficiency
differences in using optical eye spray control systems. The total copper dispensed with
the dye was measured against the copper found in the coated leather.
5-22
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Most of the organic solvents used in the degreasing process are hazardous
materials. Therefore, tanneries have been investigating the use of aqueous
degreasing systems. There are many commercial aqueous degreasing products
available to the tanner. These products are most commonly based on blends of
nonionic surfactants.4*
Aqueous degreasing systems are not common in the United States. Solvent
degreasing systems are preferred because they have been proven to be effective.
Ongoing research indicates that aqueous systems using nonionic surfactants are still
less effective in degreasing fat-laden sheepskins than solvent systems. Therefore,
substitution of solvent systems with aqueous systems is not presently a viable
emission reduction technique for tanneries processing sheep and pig skins.47
5.2.5 Emission Reductions and Waterproofing Operations
As discussed in Section 3.0, waterproof finishing is considered separate from
finishing operations. Waterproof is actually a term that collectively describes three
finished leather properties: a) water penetration resistance; b) water absorption; and
c) water repellency. These properties are desirable in various leather products and
particularly in footwear.
Silicones are the most efficient means of increasing water penetration
resistance. The backbone of silicone polymers consists of repeating siloxane units.
The stability of the link is responsible for the unique properties of these polymers
which include stability at high temperatures and good resistance to chemicals. As a
result of silicone treatment, the water penetration resistance of footwear can be nearly
100 percent. Because of the high degree of water penetration resistance that silicones
impart on the leather, leather industry customers such as the Department of Defense
usually require that leather be treated with silicone.
Silicones are normally applied using organic solvents, many of which contain
HAP's. At present, there is no known substitute for solvent-based silicone coatings
that can achieve the desired water penetration resistance qualities demanded by
customers.48 Therefore, emission reductions cannot be achieved through substitution
with water-based coatings.
Water absorption properties are also desirable on many leather footwear
products. Water absorption can be achieved by silicone impregnation and also
through hydrophobic retanning in the wet ends process. The hydrophobic retanning
process does not produce any air emissions. Therefore, depending on the degree of
water absorption needed, either technology can be used. When hydrophobic
retanning can be used rather than silicone impregnation, reductions in air emissions
can be achieved.
5-23
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Water repellency can be achieved using conventional finishing technology.
Some top coats impart water repellency characteristics on the leather. Reduction of
the VOC content of these top coats can result in some reductions in emissions.
5.2.6 Radiation Curing of Top Coats
Radiation curing is a relatively new technology and is just emerging as a
potential technique for finishing leather. As such, economic viability and market
demand for this technique are unproven. However, these coating formulations contain
materials which are 100 percent reactive, and polymerize to form a coating without
emitting volatile organic compounds. Radiation curing of leather topcoats has been
used in limited production in Europe and may prove to be an alternative leather
finishing process with low or no solvent emissions.
Radiation curing is the polymerization of a chemical system by interaction with
incident radiation, specifically ultraviolet (UV) or electron beam (EB). The chemical
system is usually composed of acrylate monomers and oligomers (intermediate length
polymers) that contain reactive carbon-carbon double bonds. The oligomers provide
the basic film-forming properties of the cured coating. The monomers are used to
adjust the viscosity of the coating for application and to impart additional properties to
the cured film. In the presence of a photo initiator and UV irradiation, the monomers
and oligomers are converted to a solid polymer with properties that frequently surpass
those of conventional solvent-borne coatings.48
There are several disadvantages associated with this technology. First, the
monomers and UV initiators required by the process are toxic. Second, there is
concern about the ability of UV light to penetrate heavier pigmented coatings. And
finally, there are costs associated with development of the process and purchase of
equipment. The initial capital expenditures may exceed $100,000 for a multi-lamp UV
system. An EB system may cost several times this amount and these costs do not
include changes in coating equipment needed for either technology. Coating
formulation costs for UV/EB systems are expected to be higher than their
conventional counterparts with the photo initiators being the most expensive
components.5*"1
5.3 References
1. U.S. Environmental Protection Agency. Enabling Document. The Measurement
Solution - Using a Temporary Total Enclosure for Capture Efficiency Testing.
Publication No. EPA-450/4-9-020. Final Draft. August, 1991.
2. Reference 1.
5-24
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3. Trip Report. Mitsch, B.F. and Howie, R.H., Alpha-Gamma Technologies, Inc. to
Iliam Rosario, Industrial Studies Branch, Office of Air Quality Planning and
Standards, U.S. EPA. April 6, 1993. Final trip report of visit to Mercersburg
Tanning, Mercersburg, PA, on January 8, 1993.
4. Reference 3.
5. Trip Report. Mitsch, B.F. and Howie, R.H., Alpha-Gamma Technologies, Inc. to
Iliam Rosario, Industrial Studies Branch, Office of Air Quality Planning and
Standards, U. S. EPA. April 7, 1993. Final trip report of visit to Seton Company,
Saxton, PA, on January 7, 1993.
6. Memorandum and attachments from Farmer, J.R., Emission Standards Division,
U. S. EPA, to Distribution. Thermal Incinerator Performance for NSPS. August 22,
1980. 29pgs.
7. Letter and attachments from Lockaby, H.G., Spectrum Engineering to Mitsch, B.F.,
Alpha-Gamma Technologies, Inc. February 11, 1993. 1 p.
8. Letter and attachments from Collard, W., Salem Engelhard to Mitsch, B.F.,
Alpha-Gamma Technologies, Inc. January 13, 1993.
9. Reference 3.
10. Reference 5.
11. References.
12. Bethea, R.M., Air Pollution Control Technology. New York, Van Nostrand Reinhold
Company. 1978. p 395.
13. Telecon. Caldwell, M.J., Midwest Research Institute, with Minor, J., M&W
Industries. June 20, 1991. Discussion about catalytic incineration.
14. Radian Corporation. Catalytic incineration for control of VOC emissions. Park
Ridge, New Jersey, Noyes Publications. 1985, pp 4-5.
15. Reference 1, p 425.
16. Reference 6, pp 12-24.
17. Reference 4, pp 12-24.
18. Reference 6, pp 12-24.
5-25
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19. Crane, G. Carbon Adsorption for VOC Control. U. S. Environmental Protection
Agency. Research Triangle Park, NC. January 1982. p. 23.
20. Kenson, R.E. Operating Results from KPR Systems for VOC Control in Paint Spray
Booths. Met-Pro Corporation. Harleyville, PA. (Presented at the CCA Surface
Coating '88 Seminar and Exhibition. Grand Rapids, Ml. May 18, 1988.) 10 p.
21. VIC Manufacturing. Carbon Adsorption/Emission Control. Minneapolis, MN.
22. U. S. Environmental Protection Agency. Carbon Adsorption for Control of VOC
Emissions: Theory and Full Scale System Performance. Publication No.
EPA-450/3-88-012. June 1988.
23. Prudent Practices for Disposal of Chemicals from Laboratories. National Academy
Press. Washington, D.C. 1983, pp 4-1 to 4-44.
24. Reference 12, pp 375-376.
25. Reference 12, p. 366.
26. Calgon Corporation. Introduction to Vapor Phase Adsorption using Granular
Activated Carbon, pp 11-1 through 11-16.
27. Reference 12, pp 382-387.
28. Reference 26.
29. Reference 26.
30. U. S. Environmental Protection Agency. Guideline Series. Control of Volatile
Organic Compound Emissions from Wood Furniture Coating Operations. Draft
Chapters 1-4. October 1991. pp 3-21 through 3-22.
31. Reference 30, pp 3-23 through 3-24.
32. Norton, L.E., Bryan, R.J., and Becvar, D.P. (Engineering-Science, Inc.). Evaluation
of Paint Spray Booth Utilizing Air Recirculation. Prepared for the U.S.
Environmental Protection Agency. Cincinnati, Ohio. Publication No. EPA-600/2-
84-143.
33. Ayer, J. (Acurex Corporation). Split-flow Exhaust for the Economic Control of VOC
Emissions from Paint Spray Booths. Prepared for the U. S. Environmental
Protection Agency. Research Triangle PArk, NC. Paper No. 90-104.3 for
presentation at the 83rd Annual Meeting of. the Air and Waste Management
Association. June 24-29, 1990. 12 pp.
5-26
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34. Reference 30, pp 3-42 through 3-43.
35. Mobil Zone Associates. Mobil Zone Spray Booth for Reduction of VOC
Contaminated Air Prepared for the U. S. Environmental Protection Agency.
Research Triangle Park, NC. Contract No. 68D90122. April 12, 1990. 17 pp.
36. Reference 35.
37. Telecon. Mitsch, B.F., Alpha-Gamma Technologies, Inc., with Levi, J., Stahl USA.
January 11, 1993. Discussion about leather finishing chemicals and trends.
38. Trip Report. Mitsch, B.F., .Alpha-Gamma Technologies, Inc. to Iliam Rosano,
Industrial Studies-Branch, Office of Air Quality Planning and Standards, U. S. EPA.
March 29,1993. Final trip report of visit to Eagle Ottawa Leather Company, Grand
Haven, Michigan on December 8, 1992.
39. South Coast Air Quality Management District. Rule 1136.
40. U. S. Environmental Protection Agency. Office of Air Quality Planning and
Standards. Surface Coating of Plastic Parts. Draft Control Techniques Guidelines.
October 1, 1992.
41. Stockman, G. Determination of Spray Machine Transfer Efficiency for Leather
Finishing. JALCA, Volume 83. 1988.
42. Technical Support Document for the Proposed Wisconsin Administrative Code Rule
to Limit VOC Emission from Major Leather Coating Facilities. Wisconsin
Department of Natural Resources. 1986.
43. Reference 41.
44. Telecon. Mitsch, B.F, Alpha-Gamma Technologies, Inc. with Boynton, M.,
Hampton Machine Company. December 30, 1992. Discussion regarding use of
rotary spray machines.
45. Bienkiewicz, K. Physical Chemistry of Leather Making. Malabar, Florida: Krieger
Publishing Company. 1983.
46. Walters, P. J. and Price, S.M. A Study of Aqueous Degreasing of Australian Wooly
Sheepskins using Nonionic Surfactants. Journal of the Society of Leather
Technologists and Chemists. Volume 75, p 197. 1991.
47. Reference 46.
48. Telecon. Mitsch, B.F., and S.C. McClintock, Alpha-Gamma Technologies, Inc. with
5-27
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Rutland, F.H., Leather Industry Research Laboratory. March 3,1993. Clarification
of information collected regarding the leather tanning and finishing industry.
49. Scholnick, F. Radiation Curing of Leather Finishes: Pros and Cons JALCA
Volume 85, 1990.
50. References!
51. Telecon. McClintock, S.C., Alpha-Gamma Technologies, Inc., with Johnson, M.
and Guarino, J., UCB Radcure, Inc. March 12, 1993.
5-28
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6.0 STATE AND LOCAL REGULATIONS AFFECTING THE LEATHER
TANNING AND FINISHING INDUSTRY
Six existing or proposed State and local regulations affecting the leather tanning
and finishing industry have been identified. The existing regulations are in the States
of New Jersey, New York, and Wisconsin. Regulations have been proposed in Illinois
and Massachusetts and in the Monterey Bay Air Unified Air Pollution Control District.
All of these State and local regulations are targeted at leather finishing
operations. Of the 6 regulations identified, 4 impose limits on the VOC content of the
coating materials. One of the regulations establishes emission limits based on the
amount of VOC emitted per unit of leather finished. And one regulation includes
characteristics of both formats - a limit on VOC content of the coating and a limit on
emissions based on VOC emitted per unit of leather finished. Table 6-1 summarizes
the emission limitations established by these regulations.
Each of these regulations is discussed below. Appendix C contains copies of
the full texts of each regulation. The full technical justification for the Wisconsin rule is
also included in the appendix.
6.1 Regulations limiting VOC content of the finishing coatings
Three of the State and local regulations identified limit the VOC content of the
finishing material. These regulations are found in New Jersey, New York, and
Massachusetts. New Jersey was the first State to adopt this type of regulation, and
New York and Massachusetts adopted the New Jersey rule.
6.1.1 State of New Jersey
The New Jersey rule for leather finishing is found in the New Jersey
Administrative Code (N.J.A.C), Title 7, Chapter 27, Subchapter 16, Section 5. This
section addresses surface coating and graphic arts operations as well as
miscellaneous surface coating operations. The full text of N.J.A.C. 7:27 is provided in
Appendix C.
t
For leather finishing operations, the maximum allowable VOC content per
volume of coating (minus water) is 5.8 pounds per gallon (0.70 kilograms per liter).
This limit was derived by determining.the equivalent reduction achievable by reducing
6-1
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Table 6-1. Summary of Existing and Proposed State/Local Regulations
State
VOC Limitations
Illinois
Monterey Bay
Massachusetts
New Jersey
New York
Wisconsin
3.5 Ibs of VOC's per gallon of base and
intermediate coats; 38 Ibs VOC emissions per
1000 sq. ft. for top coats; 10 tons of VOC per year
for stain coatings.
7.5 Ibs of VOC per gallon of coating (minus water)
for stain and oil coatings; 1.3 Ibs per gallon for
resins, and 4.0 Ibs per gallon for top coats.
27.4 Ibs of VOC per gallon of solids applied.
5.8 Ibs of VOC per gallon of coating (minus water).
5.8 Ibs of VOC per gallon of coating (minus water).
38 Ibs of VOC per 1000 sq. ft. of finished leather.
6-2
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the VOC content of the coating as compared to emission reductions achievable using
add-on controls. A number of assumptions were used by the State of New Jersey in
developing this limit.
First, it was assumed that the typical coating formulation used by the leather
industry contains 7 pounds of organic solvent per gallon and that the average solvent
density is 7.36 pounds per gallon. Reasonably available control for this type of
operation was expected to involve capture and venting to an incinerator. A capture
efficiency of 85 percent was assumed along with a destruction efficiency of 95 percent.
Using a solids-applied equation, it was determined that the VOC content of the coating
must be reduced to 5.8 pounds per gallon to achieve the equivalent 81 percent
reduction obtainable using capture and add-on controls.
The 5.8 pounds per gallon limit must be met on a daily basis. If more than one
coating is used, a daily mean VOC content is determined using a formula provided in
the rule. If coatings having VOC contents higher than 5.8 pounds per gallon are
applied, control equipment must be used to reduce VOC emissions to a specific
overall control efficiency. Quarterly reporting requirements are also specified.
6.1.2 State of New York
The New York State regulation for leather finishing is found in Title 6, Part 228
of the State code. Specific reference to leather coating lines is found in Section 228.9
of this part. Section 228.9 contains a table that itemizes limits on various processes
including leather coating lines. The limit for leather coating is identical to that found in
New Jersey, 5.8 pounds of VOC per gallon of coating minus water.
Discussions with State of New York representatives indicate that New York
adopted the New Jersey rule in total. The rule was initially applicable only in the New
York City metropolitan area. However, most of the leather finishing facilities are
'located in the central part of the State and were not impacted by the rule. The
establishment of the Northeast transport region by the Clean Air Act has caused the
State to expand the rule to cover major sources statewide. Since New York is in the
transport region, a major source is one that emits 50 tons per year or greater of
VOC's. Some of the facilities located in upstate New York may now be impacted by
the rule.
6.1.3 State of Massachusetts
The State of Massachusetts proposed a regulation to limit emissions from
leather finishing facilities as part of State Implementation Plan (SIP) revisions needed to
comply with the Clean Air Act Amendments. Public hearings were being held on the
proposed regulation in the Fall of 1992.
6-3
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The State is in the process of setting RACT emissions limitations on 7 industrial
categories not covered by their existing regulation, with leather surface coating being
one of the 7 categories. The RACT limitations will be imposed on all stationary
sources having the potential to emit 50 tons of VOC per year. The 50 ton limit is in
response to the Northeast transportation provision of the Act.
Massachusetts is proposing a limit of 27.4 pounds of VOC per gallon of solids
applied. This format parallels those of New Jersey and New York, but relates
emissions directly to solids application as opposed to gallons of coating minus water.
6.1.4 Monterey Bay Unified Air Pollution Control District
The Monterey Bay Unified Air Pollution Control District (MBUAPCD), located in
Northern California, has proposed a rule to limit VOC emissions from leather
processing operations. The rule is expected to be promulgated in the Fall of 1993.
The MBUAPCD rule requires sources that emit greater than 250 tons per year
of VOC to use control technology that achieves a combined efficiency of 85 percent.
For sources that emit less than 250 tons per year, limits on the VOC content of the
coating material have been specified. These limits are: a) 7.5 pounds per gallon of
material (minus water) for stain coatings; b) 7.5 pounds per gallon of material (minus
water) for oil coatings; c) 1.3 pounds per gallon of material (minus water) for resin
coatings; and d) 4.0 pounds per gallon of material (minus water) for top coats. It is
expected that these limits will become stricter in later years.
In addition to the limits on VOC content of the coatings, the rule also specifies
application methods and equipment to be used for leather finishing. For example, roll
coating is required for oil application and photoelectric controls are required for spray
guns used to apply other VOC-containing treatments.
6.2 Regulations limiting emissions to unit of product finished
The State of Wisconsin regulation limits VOC emissions by the square footage
of leather finished. The Wisconsin rule was promulgated on March 1, 1990.
Development of the regulation involved an extensive effort by Wisconsin's Department
of Natural Resources over a 6 year period. In developing the rule, Wisconsin focused
on the tanneries located in the Southeast Wisconsin nonattainment area. The
Department surveyed four tanneries in this area and solicited information on the VOC
content of coatings used by each facility.
The emission limit developed by Wisconsin is based on the coatings formulation
data obtained from the tanneries. The State recognized the diversity of coatings used
in finishing leather, and divided the coatings into five functional classes. These
functional classes are impregnation, stain, base, effect, and final finish.
6-4
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Table 6-2 shows the VOC emission rates identified for these functional classes for
three types of application methods.
Based on the emission rates identified, Wisconsin determined that the 16th
percentile in each spray coating range (frequency distribution) represented PACT.
The emission limit was determined by adding the RACT level for each functional class:
6.0 pounds per 1,000 square feet for impregnation; 19 pounds per 1,000 square feet
for stain; 2 pounds per 1,000 square feet for base; 4 pounds per 1,000 square feet for
effect; and 7 pounds per 1,000 square feet for finish. Adding the emission limits for
each functional class yielded an overall emission limit of 38 pounds of VOC per 1000
square feet of finished leather.
Determination of compliance is based on a formula that takes into account the
total VOC's emitted during the day as compared to a prorated surface area of leather
finished. In order to determine compliance, the plant must keep detailed records of all
coating formulations and the amount of each coating needed to finish each type of
leather product. These records are kept on a daily basis and require computer
capabilities to effectively monitor coating usage and surface area of leather finished.
A copy of the technical support document developed to support the Wisconsin
rulemaking is provided in Appendix C.
6.3 The State of Illinois
The State of Illinois proposed regulation incorporates components of both the
New Jersey rule and the Wisconsin rule. As part of their strategy to comply with the
Clean Air Act Amendments, Illinois is developing rules to implement RACT for all major
sources. In the Chicago area, which is a severe nonattainment area for ozone, a
major source is 25 tons per year.
The Federal Implementation Plan (FIP) in effect in Illinois established RACT for
100 ton non-CTG sources to be either 3.5 pounds of VOC per gallon of coating
(minus water) or an overall emission reduction of 81 percent. In evaluating smaller
non-CTG sources such as leather finishing plants, Illinois determined that the 3.5
pounds/gallon limit was too strict.
Based on a survey of the leather finishing industry conducted for EPA,1 the
State determined that the 3.5 pounds/gallon limit was achievable for base and
intermediate coatings. However, top coats and stains used in specialty leathers
cannot meet this limit. Illinois has proposed using Wisconsin's RACT limitation of 38
pounds per 1,000 square feet of finished leather for these specialty leathers. In
addition, a limit of 10 tons per year of VOC emissions from stains other than those
used in specialty leathers is in the rule.
6-5
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Table 6-2. State of Wisconsin - Emission Rates Identified by
Finishing Application Method*
Application Method
Row
Air Atomized Spray
Air Atomized Spray
Air Atomized Spray
Air Atomized Spray
Air Atomized Spray
Roll
Roll
Coating Type
Oil Impregnation
Stain
Middle
Emulsion
Top Coat
Top Coat
Oil Impregnation
Stain
VOC Emission Rate
(kg/100 m2)
2.39-9.76.
7.81-14.16
0.33-6.41
3.42b
1.95-12.7
2.44-16.11
2.93b
1.12-2.93
"Based on information received from Amity Leather Products Company, Gebhardt-Vogel
Tanning Company, and Pfister-Vogel Tanning Company during November 1985 - April
1986.
bOnly one value presented from the above listed leather finishers.
6-6
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A technical document was prepared by one source impacted by these limits as
part of Illinois' rulemaking process. Copies of that report are not available at this time
due to proprietary reasons.
6.4 References
1. Science Applications International Corporation. Assisting the New England States
in Implementing Reasonable Available Control Technology at Leather Finishing
Plants. Final Report submitted to the U. S. Environmental Protection Agency,
Office of Air Quality Planning and Standards. July 31, 1992.
6-7
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APPENDIX A
EMISSIONS DATA
A-i
-------
-------
A.1 Introduction to Appendix A
This appendix contains all of the emissions data collected during the course of
the project. Data were obtained from EPA data bases such as the Aerometric
Information Retrieval System (AIRS) and the Toxic Release Inventory (TRI). Additional
data were obtained from State agencies and from plant sites.
Seventy-nine facilities are listed in the appendix. For many facilities, emissions
are not reported (NR). The emissions from these facilities are either below the
reporting threshold for the TRI or were not reported in any other available data base.
A-ii
-------
List of Tanning and Finishing Facilities in the United States
KEY: TRI - Toxic Release Inventory
AIRS - Aerometric Information Retrieval System
Facility
Calnap Tanning
Salz Leathers, Inc.
Western Tanning, Inc.
ACME Sponge & Chamois Co. Inc
Oshkosh Tanning Co., Inc.
Gutman and Company
Horween Leather Company
Much Leather Company
Carr Leather Co.
Barnet Corporation
Bond Leather Co., Inc.
Salem Suede, Inc.
Richard Tanning Co.
W.D. Byron & Sons Inc.
Prime Tanning Co., Inc
Camden Tanning Corporation
Irving Tanning Company
Rockland Leathers, Inc.
Wilton Tanning Company
Eagle Ottawa Leather Co.
Whitehall Leather Company
S.B. Foot Tanning Company
Blueside Companies, Inc.
Hermann Oak Leather Company
Lackawanna Leather Co.
Lackawanna Leather Co.
Schwartz Leather Company
New Jersey Tanning Co., Inc.
Seton Company
UDO Finishing Co
American Leather
Androme Leather Corp
Colonial Tanning Corp.
Fashion Tanning Co., Inc.
City
Napa
Santa Cruz
Delta
Tarpon Springs
Boone
Chicago
Chicago
Chicago
Lynn
Peabody
Peabody
Salem
Salem
Williamsport
Berwick
Camden
Hartland
Rockland
Wilton
Grand Haven
Whitehall
Red Wing
Saint Joseph
St. Loius
Conover
Omaha
Carlstadt
Newark
Newark
Newark
Rahway
Gloversville
Gloversville
Gloversville
A-1
State
CA
CA
CO
FL
IA
IL
IL
IL
MA
MA
MA
MA
MA
MD
ME
ME
ME
ME
ME
Ml
Ml
MN
MO
MO
NC
NE
NJ
NJ
NJ
NJ
NJ
NY
NY
NY
Source of
Emission
Data
AIRS
TRI, AIRS, Mont. Bay
TRI
TRI
TRI
AIRS
TRI, AIRS
AIRS
TRI
AIRS
TRI
TRI
AIRS
TRI
TRI, AIRS
AIRS
TRI
AIRS
AIRS
TRI
TRI
TRI, AIRS
TRI
TRI
TRI, AIRS
TRI
TRI
TRI
TRI, NJ permits
.NJ permits
AIRS, NJ permits
NY data
TRI
TRI, NY data
-------
List of Tanning and Finishing Facilities in the United States
KEY: TRI - Toxic Release Inventory
AIRS - Aerometric Information Retrieval System
Facility
Framglo Plant
Independent Leather Mfg. Corp.
JBF industries inc.
Leather Agent Inc
Pan American Tanning Corp.
Twin City Leather CO., Inc.
Wood & Hyde Leather co Inc
Moench Tannning Company
Adirondac Leather Inc
Allied Split Corp.
Arrow Leather Finishing Co
Carville National Leather Co
Classic Leather corp
Gordon Finishing Co Inc
H & J Leather Finishers Inc
Karg Brothers, Inc.
K-lynn Split Inc
Pearl Leather Finishers Inc
Peerless Tanning Co Inc
Simco Leather Corp.
Townsend Leather Co
Conneaut Leather Inc.
Howes Leather Co., Inc.
Garden State Tanning
Mercersburg Tanning
Garden State Tanning
Seton Company
Westfield Tanning Company
Volunteer Leather Company
Lannom Tannery
Tennessee Tanning Co.
Coey Tanning Co., Inc.
S.B. Foot Tanning Co.
Fox Valley Leathers, Inc.
City
Gloversville
Gloversville
Gioversviiie
Gloversville
Gloversville
Gloversville
Gloversville
Gowanda
Johnstown
Johnstown
Johnstown
Johnstown
Johnstown
Johnstown
Johnstown
Johnstown
Johnstown
Johnstown
Johnstown
Johnstown
Johnstown
Conneaut
Curwensville
Fleetwood
Mercersburg
Reading
Saxton
Westfield
Milan
Tullahoma
Tullahoma
Wartrace
Cactus
North Salt Lake
State
• NY
NY
NY
NY
NY
NY
NY
NY
NY
NY
NY
NY
NY
NY
NY
NY
NY
NY
NY
NY
NY
OH
PA
PA
PA
PA
PA
PA
TN
TN
TN
TN
TX
UT
Source of
Emission
Data
NY data
TRI
TRi, NY data
NY data
TRI, NY data
TRI
NY data
TRI
NY data
TRI, NY data
NY data
NY data
NY data
NY data
NY data
TRI, NY data
NY data
TRI
NY data
TRI, NY data
NY data
TRI
TRI, AIRS
TRI, AIRS
TRI
TRI
TRI
TRI, AIRS
TRI, AIRS, TN permits
ILG, TN permits
TRI.TN permits
TRI, TN permits
TRI
TRI
A-2
-------
List of Tanning and Finishing Facilities in the United States
KEY: TRI -Toxic Release Inventory
AIRS - Aerometric Information Retrieval System
Facility
Berlin Tanning Co.
Cudahy Tanning Company
A.F. Gallun & Sons Co.
Blackhawk Tanning Co.
Gebhardt-Vogel Tanning Co.
Gebhardt-Vogel Tanning Co.
Paul Flagg Inc
PFister & Vogel Tanning Co.
Theile Tanning Co.
Paul Flagg Leather Corp.
Howes Leather Co., Inc.
City
Berlin
Cudahy
Milwaukee
Milwaukee
Milwaukee
Milwaukee
Milwaukee
Milwaukee
Milwaukee
Sheboygan
Frank
State
Wl
Wl
Wl
Wl
Wl
Wl
Wl
Wl
Wl
Wl
WV
Source of
Emission
Data
TRI
TRI
TRI
AIRS
TRI
TRI
AIRS
TRI
TRI
TRI
TRI
Total Number of Facilities Reporting 79
A-3
-------
1987-1990 VOC and HAP Emissions from Tanning Operations
Facility
Cal Nap Tanning
Napa, CA
Salz Leathers, Inc.
Santa Cruz, CA
Western Tanning, Inc.
Delta, CO
ACME Sponge & Chamois
Tarpon Springs, FL
Oshkosh Tanning Co., Inc.
Boone, IA
Gutman and Company
Chicago, IL
Horween Leather Compan
Chicago, IL
Total HAP Total VOC Total NonHAP Total HAP
Year Emissions Emissions VOC emissions nonVOC emissions
(Ibs/yr) (HAP&nonHAP) (Ibs/yr) (Ibs/yr)
(Ibs/vr)
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1991
NR
NR
NR
NR
250
250
250
250
500
250
250
5
NR
31850
42000
26644
NR
NR
NR
NR
NR
NR
NR
NR
31000
47000
14950
53250
NR
NR
NR
NR
NR
37000
33214
NR
NR
250
NR
NR
NR
NR
31850
42000
26638
NR
NR
NR
NR
NR
NR
NR
NR
31000
47000
14950
53250
NR
NR
NR
NR
NR
37000
'33214
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
250
250
250
250
250
250
250
5
NR
NR
NR
6
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
A-4
-------
1987-1990 VOC and HAP Emissions from Tanning Operations
Facility
Huch Leather Company
Chicago, IL
Carr Leather Co.
Lynn, MA
Bamet Corp.
Peabody, MA
Bond Leather Co., Inc.
Peabody, MA
Rex Finishing Inc.
Peabody, MA
Richard Tanning Co.
Salem, MA
Salem Suede, Inc.
Salem, MA
W.D. Byron & Sons Inc.
Williamsport, MO
Total HAP Total VOC Total NonHAP Total HAP
Year Emissions Emissions VOC emissions nonVOC emissions
(Ibs/yr) (HAP&nonHAP) (Ibs/yr) (Ibs/yr)
(Ibs/yr)
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
16750
8610
26074
22884
NR
NR
NR
461183
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
16750
8610
26074
22884
NR
NR
NR
470332
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
9149
NR
NR
NR
NR
NR
Nrt
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
A-5
-------
1987-1990 VOC and HAP Emissions from Tanning Operations
Facility
Prime Tanning Co., Inc
Berwick, ME
Camden Tanning Corporat
Camden, ME
In/ing Tanning Company
Hartand, ME
Rockland Leathers, Inc.
Rockland, ME
Wilton Tanning Company
Wilton, ME
Eagle Ottawa Leather Co.
Grand Haven, Ml
Whitehall Leather Compan
Whitehall, Ml
S.B. Foot Tanning Compa
Red Wing, MN
Year
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
Total HAP Total VOC Total NonHAP Total HAP
Emissions Emissions VOC emissions nonVOC emissions
(Ibs/yr) (HAP&nonHAP) (Ibs/yr) (ibs/yr)
(Ibs/yr)
460750
434957
881296
1058585
NR
NR
NR
NR
676350
495981
261863
398886
NR
NR
NR
NR
NR
NR
NR
NR
2820000
2730000
2618000
1915231
4500
NR
NR
NR
309468
284979
260866
154811
682500
527805
970872
1058585
NR~
NR
NR
NR
1241070
1486742
277635
398886
NR
NR
NR
NR
NR
NR
NR
NR
3570000
3360000
2977000
2154210
4500
NR
NR
NR
349606
317008
318293
185952
222000
92848 .
89576
NR
NR
' NR
NR
NR
564720
990761
15772
NR
NR
NR
NR
NR
NR
NR
NR
NR
750000
630000
359000
239234
NR
NR
NR
NR
41000
32891
58289
31306
250
NR
NR
NR
NR
NF<
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
255
NR
NR
NR
NR
862
862
862
165
A-6
-------
1987-1990 VOC and HAP Emissions from Tanning Operations
Facility
Hermann Oak Leather Co
St Loius, MO
Blueside Companies, Inc.
Saint Joseph, MO
Lackawanna Leather Co.
Conover, NC
Lackawanna Leather Co.
Omaha, NE
Schwartz Leather Compan
Carlstadt, NJ
New Jersey Tanning Co., I
Newark, NJ
Seton Company
Newark, NJ
UDO Finishing
Newark, NJ
Year
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
Total HAP
Emissions
(Ibs/yr)
NR
NR
NR
NR
NR
NR
NR
250
628195
372390
551025
319586
NR
NR
NR
239005
NR
250
NR
255
NR
NR
NR
NR
1678500
609310
658750
1359991
NR
NR
NR
NR
Total VOC
Emissions
(HAP & nonHAP)
(Ibs/vr)
NR
NR
NR
NR
NR
NR
NR
250
674752
670988
728647
506759
NR
NR
NR
318962
NR
250
NR
255
NR
NR
NR
NR
1678500
608810
658250
1359991
NR
NR
NR
NR
Total NonHAP
VOC emissions
(Ibs/yr)
NR
NR
NR
NR
NR
NR
NR
NR
46557
298598
177622
187173
NR
NR
NR
79957
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
Total HAP
nonVOC emissions
(Ibs/yr)
NR
NR
NR
NR
NR
N9
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
500
500
NR
NR
NR
NR
NR
A-7
-------
1987-1990 VOC and HAP Emissions from Tanning Operations
Facility
American Leather
Rahway, NJ
Androme Leather Corp
Gloversville, NY
Colonial Tanning Corp.
Gloversville, NY
Fashion Tanning Co., Inc.
Gloversviile, NY
Framglo Plant
Gloversville, NY
JBF Industries Inc.
Gloversville, NY
Independent Leather Mfg.
Gloversville, NY
Leather Agent Inc.
Gloversville, NY
Year
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
Total HAP
Emissions
(Ibs/yr)
NR
NR
NR
30994
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
7900
NR
NR
NR
NR
NR
NR
NR
NR
Total VOC
Emissions
(HAP & nonHAP)
(Ibs/yr)
NR
NR
NR
56031
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
7900
NR
NR
NR
NR
NR
NR
NR
NR
Total NonHAP
VOC emissions
(Ibs/yr)
NR
NR
NR
25037
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
Total HAP
nonVOC emissions
(Ibs/yr)
NR
NR
NR
NR
NR
N3
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
A-8
-------
1987-1990 VOC and HAP Emissions from Tanning Operations
Facility
Pan American Tanning Co
Gloversville, NY
Twin City Leather CO., Inc.
Gloversville, NY
Wood & Hyde Leather Co
Gloversville, NY
Moench Tannning Compa
Gowanda, NY
Adirondac Leather Inc
Johnstown, NY
Allied Split Corp.
Johnstown, NY
Arrow Leather Finishing C
Johnstown, NY
Carviile National Leather C
Johnstown, NY
Year
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1991
Total HAP
Emissions
(Ibs/yr)
28000
42250
67750
53750
NR
NR
NR
NR
NR
NR
NR
NR
285000
158145
157041
146261
NR
NR
NR
NR
NR
NR
NR
250
NR
NR
NR
NR
NR
NR
NR
NR
NR
Total VOC
Emissions
(HAP & nonHAP)
(Ibs/yr)
28000
42250
67250
53250
NR
NR
NR
NR
NR
NR
NR
NR
285000
158145
157041
159716
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
Total NonHAP
VOC emissions
(Ibs/yr)
NR
NR
NR
NR
NR
• NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
13455
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
Total HAP
nonVOC emissions
(Ibs/yr)
NR
NR
500
500
NR
NS
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
250
NR
NR
NR
NR
NR
NR
NR
NR
NR
A-9
-------
1987-1990 VOC and HAP Emissions from Tanning Operations
Facility
Classic Leather Corp
Johnstown, NY
Gordon Finishing Co Inc
Johnstown, NY
H & J Leather Finishers In
Johnstown, NY
Karg Brothers, Inc.
Johnstown, NY
K-Lynn Split Inc
Johnstown, NY
Peart Leather Finishers Inc
Johnstown, NY
Peerless Tanning Co Inc
Johnstown, NY
Total HAP Total VOC Total NonHAP Total HAP
Year Emissions Emissions VOC emissions nonVOC emissions
(Ibs/yr) (HAP&nonHAP) (Ibs/yr) (Ibs/yr)
(Ibs/Vrt
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1992
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
12000
20250
15750
13574
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
12000
20250
15250
13074
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
' NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NF1
NR
NR
NR
NR
NR
NR
NR
NR
500
500
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
A-10
-------
1987-1990 VOC and HAP Emissions from Tanning Operations
Facility
Simco Leather Corp.
Johnstown, NY
Townsend Leather Compa
Johnstown, NY
Conneaut Leather Inc.
Conneaut, OH
Howes Leather Co., Inc.
Curwensville, PA
Garden State Tanning
Fleetwood, PA
Mercersburg Tanning
Mercersburg, PA
Garden State Tanning
Reading, PA
Seton Company
Saxton, PA
Year
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1989
1990
1991
1992
Total HAP
Emissions
(Ibs/yr)
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
55298
7522
NR
NR
NR
NR
NR
NR
NR
699089
148900
225800
49500
46700
NR
NR
NR
10
NR
169444
265994
267623
Total VOC
Emissions
(HAP & nonHAP)
(Ibs/yr)
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
68092
12277
NR
NR
NR
NR
NR
NR
NR
727987
204000
236850
109050
81250
NR
NR
NR
NR
NR
NR
NR
NR
Total NonHAP
VOC emissions
(Ibs/yr)
NR
NR
NR
NR
NR
• NR
NR
NR
NR
NR
12794
4755
NR
NR
NR
NR
NR
NR
NR
28898
55100
11050
60050
35050
NR
NR
NR
NR
NR
NR
NR
NR
Total HAP
nonVOC emissions
(Ibs/yr)
NR
NR
NR
NR
NR
Nfl
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
500
500
NR
NR
NR
10
NR
NR
NR
NR
A-11
-------
1987-1990 VOC and HAP Emissions from Tanning Operations
Facility
Westfield Tanning Compa
Westfiald, PA
Volunteer Leather Compa
Milan, TN
Lannom Tannery
Tullahoma, TN
Tennessee Tanning Co.
Tullahoma, TN
Coey Tanning Co., Inc.
Wartrace, TN
S.B. Foot Tanning Co.
Cactus, TX
Fox Valley Leathers, Inc.
North Salt Lake, UT
Total HAP
Year Emissions
(!bs/yr)
1987
1988
1989
1990
1987 .
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
NR
NR
NR
NR
66000
81000
64SCC
45500
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
Total VOC Total NonHAP Total HAP
Emissions VOC emissions nonVOC emissions
(HAP & nonHAP) (Ibs/yr) (Ibs/yr)
(Ibs/vrt
NR
NR
NR
NR
85000
115000
75750
45500
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
19000
34000
1125Q
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
Ntf
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
A-12
-------
1987-1990 VOC and HAP Emissions from Tanning Operations
Facility
Berlin Tanning Co.
Berlin , Wl
Cudahy Tanning Compan
Cudahy, Wl
A.F. Gallun & Sons Co.
Milwaukee, Wl
Blackhawk Tanning Co
Milwaukee, Wl
Gebhardt-Vogel Tanning
Milwaukee, Wl
Gebhardt-Vogel Tanning
Milwaukee, Wl
Paul Flagg Leather
Milwaukee, Wl
PFister & Vogel Tanning C
Milwaukee, Wl
Total HAP Total VOC Total NonHAP Total HAP
Year Emissions Emissions VOC emissions nonVOC emissions
(Ibs/yr) (HAP&nonHAP) (Ibs/yr) (Ibs/yr)
(Ibs/yr)
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
250
NR
NR
NR
161050
99250
77950
78050
250
250
250
NR
NR
NR
NR
NR
500
250
250
45
40750
48600
20000
51280
*
NR
NR
NR
NR
159022
171018
111090
146260 .
14250
NR
NR
NR
160800
99000
77700
77800
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
54750
65100
31000
51200
NR
NR
NR
NR
193100
256600
129650
172070
14250
NR
NR
.NR
NR
• NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
14250
16750
11250
NR
NR
NR
NR
NR
NR
NR
34100
85600
19700
26600
250
NR
NR
NR
250
2EO
250
250
250
250
250
NR
NR
NR
NR
NR
500
250
250
45
250
250
250
80
NR
NR
NR
NR
22
18
1140
790
A-13
-------
1987-1990 VOC and HAP Emissions from Tanning Operations
Facility
Theile Tanning Co.
Milwaukee, Wl
Paul Flagg Leather Corp.
Sheboygan, Wl
Howes Leather Co., Inc.
Frank, WV
Year
1987
1988
1989
1990
1987
1988
1989
1990
1987
1988
1989
1990
Total HAP
Emissions
(Ibs/yr)
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
10
Total VOC
Emissions
(HAP & nonHAP)
(Ibs/yr)
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
Total NonHAP
VOC emissions
(Ibs/yr)
NR
NR
NR
NR
NR
NR
' NR
NR
NR
NR
NR
NR
NR
NR
Total HAP
nonVOC emissions
(Ibs/yr)
NR
NR
NR
NR
NR
N!3
k ir>
[\n
NR
NR
NR
NR
10
A-14
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APPENDIX B
LEATHER TANNING AND FINISHING PLANTS - CASE STUDIES
B-i
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B.1 Introduction to Appendix B
Appendix B includes case studies for five leather manufacturing facilities. The
information included in the case studies was obtained during site visits to the respective
plants. All information claimed as confidential has been removed from the case studies.
B-ii
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PLANT A
A. General
Plant A is a retanning and finishing facility that produces leather used for
manufacturing shoes, handbags, and belts. These products tend to be leathers with
heavy, oily finishes.
The raw materials used at the plant are wet blue, or crust leather, that has been
chrome tanned at another leather tannery. The primary supplier of the wet blues is a
tannery located in another State. The wet blues are retanned prior to being finished.
The crust leather has already been retanned and is simply finished by Plant A.
Most of the finishing is conducted in the newest section of the plant that houses
three leather coating lines, two of which are vented to an incinerator to control VOC
emissions. Older finishing lines are located in the original plant buildings and are
primarily used for specialty finishing. For example, one gun spray booths are used to
create shadowing and antiquing effects on the leather by altering the angle of the
spray.
. Plant A is capable of producing hundreds of product lines. This includes
variations in color, texture, feel, and grain thickness. Over 370 different chemicals and
additives are used to produce coatings applied during the leather finishing process.
All coatings are custom formulated on site, and coating formulations and usage are
closely tracked by the plant. The major suppliers of coating components are Stahl,
BASF, Rohm & Haas, and Mobay.
B. Process Description
The primary purpose for visiting Plant A was to observe the operation of the
newer finishing lines that are vented to a control device. Most of the time spent at the
facility was focused on this part of the operation. However, some wet-end processes
are performed at Plant A prior to finishing. The leather arrives at the plant in the wet
blue or chrome tanned condition. The wet blue hides are retanned at the plant, and
some mechanical operations are performed prior to the leather being finished. These
operations include drying, softening and splitting of the leather. Plant A primarily
finishes the grain portion (top half) following splitting, but they occasionally finish some
splits (the fleshy, or bottom half of the hide).
B-1
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Leather finishing is conducted using old and new technology. In the older
sections of the plant, one-gun finishing machines and four-gun finishing machine are
used for most of the leather finishing. The one-gun spray equipment observed during
the visit is not controlled by optical eye or mechanical sensors, and the degree of
overspray was noticeably greater than optically controlled equipment. The emissions
from these spray booths are uncontrolled. Most of the coating used in this section of
the facility are solvent-based coatings. Although Plant A is in the process of moving
most of their finishing processes to the new spray facilities, these older machines are
used to apply special effects to the leather. For example, the spray nozzle of a one-
gun machine can be angled to achieve a shadowing; effect on the leather.
in the new section of the plant, modern finishing technology is used to finish the
leather. Three finish lines are used in the new part of the plant and all of the spray
booths use eight-gun rotary sprayers that are optically controlled. The optical controls
help to minimize overspray. Typically, three types of coatings are applied to the
leather: a base coat, an intermediate coat, and a top coat.
C. Sources of Emissions
The leather finishing operation is responsible for nearly all of the VOC and
hazardous air pollutant (HAP) emissions from the facility. There are little, if any, VOC
emissions from the wet-end processes or from associated operations such as the
wastewater treatment system. Wastewater samples have been analyzed for total
organic compounds and the concentrations were less than 10 mg/L
In the older part of the plant, all of the finishing operations are uncontrolled for
VOC's. Emission control measures are in place for particulate control. Over half of
the total VOC emissions from the facility are emitted from this section of the plant.
The new section of the plant was built in 1990 and is used for the majority of
the leather finishing. There are three finishing lines located in this plant addition and
they are identified as Lines A, B, and C by the State permitting authority. At the plant
site, Line C consists of two spray booths, designated as machines 9B and 9C by the
plant, three drying ovens, and one stick dryer. Line C also has a manual coatings
operation that is identified by the plant as machine 9A. The manual operation involves
application of coatings for special effects using hand spray guns.
Line C is an uncontrolled finishing line that is used to apply water-based
coatings only. There is a VOC emissions limit of 20 tons per year for this line, along
with limitations on the VOC content of coatings applied during finishing. The limitation
on the base coatings is 3.5 pounds of VOC per gallon (minus water) and the limitation
on intermediate coatings is 2.8 pounds of VOC per gallon (minus water).
B-2
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Line A consists of two eight-gun spray booths (machines 1A and 1B) and two
catalytic dryers. Line B (machine 2) consists of one eight-gun spray booth and one
stream dryer. As stated in the permit, VOC emissions from these two lines are limited
to 35 tons per year.
All of the spray booths and dryers on lines A and B are vented to a
regenerative thermal oxidizer (RTO) supplied by Salem Engelhard. The rated capacity
of the RTO is 30,000 standard cubic feet per minute. VOC destruction efficiencies of
greater than 99 percent were determined by the tests. The incinerator is
supplemented with natural gas to maintain combustion temperatures. However, when
two spray booths are operating in tandem and applying solvent-based coatings, the
RTO temperatures can be maintained with little supplemental fuel.
Emissions data for the plant were provided following the plant visit. As noted
above, the new addition to the plant and the incinerator were built in 1990. The
emissions data given below were recorded prior to emissions testing of the RTO. A
95 percent destruction efficiency was assumed for the incinerator in estimating
emissions from the incinerator outlet.
1988 Total Plant VOC 276 tons
1989 Total Plant VOC 136 tons
1990 Total Plant VOC 154 tons
Line C 10.03 tons
VOC to RTO 54 tons
VOC out of RTO 2.7 tons
1991 Total Plant VOC 119 tons
Line C 2.2 tons
VOC to RTO 41 tons
VOC out of RTO 2.0 tons
The specific VOC emission points from the finishing operation are the vents
from the spray booths and dyers, the uncovered areas of the conveyers carrying the
leather from the spray booths and dryers, fugitive emissions from the partially covered
drums containing coating, and fugitive emissions from the finished leather. There is
also a small mixing room that is a source of fugitive emissions. The largest single
emission point in the plant is the vent to the RTO.
B-3
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D. Emission Reduction Measures
The installation of the incinerator is the major emission reduction measure -
employed by the plant. The system cost about $1.5 million dollars in 1989. The
purpose of installing the incinerator to control emissions from the plant modification
was to allow for expansion of production without exceeding any State emission
limitations. Plant A was also anticipating increased business in producing military
leather. Military leather has to be waterproofed using high VOC-based sealing
systems.
Other than the incinerator, Plant A is under little pressure to look for additional
VOC reductions. The transition to more water^based coatings will only be made when
water-based technology is capable of producing the same quality leather as the
solvent-based systems. Plant A believes that solvent-based coatings are still essential
to producing leather to meet their customers specifications. The coatings applied to
their leathers must be compatible with the finished coatings used by the shoe
manufacturers. As the water-based technology improves, solvent-based coatings may
be phased out.
Plant A has made progress in limiting emissions of some HAP's. In the 1990
Toxic Release Inventory, Plant A reported emissions of 5 HAP's: 6.38 tons of toluene;
3.48 tons of xylene; 4.63 tons of methyl ethyl ketone (MEK); 8.6 tons of glycol ethers;
and 0.25 tons of chromium. According to information provided by the plant, emissions
of toluene and MEK were eliminated in 1991 and emissions of xylene and glycol ethers
have been reduced. 1991 emissions of xylene were reported to be 2.4 tons and
emissions of glycol ethers were reported as 5.75 tons per year. These emission
reductions were the result of new coating formulations.
E. Regulatory Compliance
When Plant A decided to modify the existing facility by adding the new finishing
lines, they entered into negotiations with the State. At the time, the area was an
unclassified air quality management district. However, for the purposes of permitting,
the facility was considered to be in a non-attainment area and, therefore, subject to a
lowest achievable emission rate (LAER) determination. Part of the reason for setting
the emission limit of 35 tons on the new spray lines was to avoid new source review.
B-4
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PLANTS
A. General
T
Plant B produces automotive upholstery leather. The leather production
process is divided between two facilities. Raw hides are processed and tanned at
another facility and then shipped to Plant B. The tanned leather is referred to as crust
leather at this stage in the leather tanning and finishing process. Plant B is strictly a
finishing and cutting plant. The final product is cut automotive upholstery parts.
Plant B is a new facility that began operations in 1989. In 1992, all of the
finishing operations were transferred to this location with the exception of some minor
finishing processes that are still performed at the old site. The State has set an
emission limit of 250 tons per year (on a rolling monthly average) for the Plant B. The
area in which Plant B is located was designated as an ozone attainment area when the
facility was constructed. The 250 ton per year limit was set to avoid prevention of
significant deterioration (PSD) review. This source appears in the Best Available
Control Technology/Lowest Achievable Emission Rate (BACT/LAER) Clearinghouse.
However, the source did not actually undergo PSD review. Rather than proceed
through the review process, Plant B applied for a non-PSD permit with a 250 ton per
year limit.
B. Process Description
Plant B operates five finishing spray lines at this facility. All of the equipment
was supplied by Hampton Machine Company. Initially, four spray lines were permitted
by the State, with the fifth spray line added in 1992.
Plant B is equipped with five spray lines. Four of these spray lines are vented
to a Reeco Incinerator. The spray booths and dryers on each of these lines are totally
enclosed. The fifth spray line is not vented to the incinerator. Lines 1, 2, and 5 are
arranged in a row and can operate in series. Lines 3 and 4 are also in-line and can
be operated in series.
Both water-based and solvent-based coatings are applied to the leather. The
spray lines are designed so that solvent-based applications can be vented to the
incinerator, while water-based applications are vented to the atmosphere. Line 1 is
used to apply exclusively water-based coatings. The spray booth and dryer on this
line are not vented to the incinerator. Lines 2 and 4 are used to apply either water or
B-5
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solvent-based coatings. When solvent coatings are applied on these tines, the spray
booth and dryer exhaust are vented to the incinerator. When water-based coatings
are applied on these lines, the spray booth and dryer exhausts are vented to the
atmosphere. Lines 3 and 5 are used exclusively for applying solvent-based coatings,
usually topcoats. In general the leather receives a total of three coatings.
Occasionally, the leather receives a fourth coating.
Whenever a solvent based coating is applied on any line, the spray booth and
dryer exhaust are routed to an incinerator. The incinerator is designed to handle a
maximum flow of 24,000 cubic feet per minute (cfm). At any given time, two spray
lines can be vented to the incinerator. The exhaust flow from each finishing line is
approximately 12,000 cfm. Theoretically, all five lines can be operating at one time if
only two are applying solvent based coatings.
There is no process wastewater discharged from the plant. All process
wastewater is treated on site and then reused. The water treatment system is located
inside the building. Any emissions resulting from the treatment (volatilization of
organic contaminates) of wastewater are exhausted through the building ventilation. A
filter cake is generated from the waste water treatment which is disposed of as
hazardous waste.
C. Sources of Emissions
The major source of emissions at the plant is the incinerator stack. Four of the
5 finishing lines can potentially be vented to the incinerator when solvent-based
coatings are being applied. At any given time, a maximum of two lines can be vented
to the unit. All of the spray booths and dryers are totally enclosed. Capture efficiency
testing has been conducted on two occasions and capture efficiencies of 65 to over
90 percent have been estimated. Based on test results, there are some fugitive
emissions from the drying ovens, and also some emissions from spray booths not
vented to the incinerator.
An additional source of VOC emissions is the mixing room. Plant B estimates
emissions from the mixing room to be approximately 10 tons per year. This estimate
is based on analysis of grab samples taken from the mixing room ventilation system,
personnel monitoring in the mixing room, and mixing room ventilation rates.
Plant B maintains a detailed tracking system of product usage and VOC
emissions. In all spray booths using water-based coatings, all overspray is collected
and reused or disposed. Plastic sheets are placed on the bottom of the spray booths.
The water-based coating is collected on the plastic and placed in buckets. The
buckets are weighed before the product is reused or disposed. Some coating
remains on the plastic sheets, and these sheets are disposed as solid waste. Prior to
disposal, all wastes are analyzed and the off-site disposal of VOC and individual toxics
B-6
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are quantified. Plant B accounts for any volatile component that leaves the plant in
solid or liquid waste in determining their air emissions.
Plant B also attempts to account for any organic compounds that stay in the
product. Based on analysis of finished leather products, Plant B has determined that
significant quantities of high boiling volatiles remain in the finished leather. This is
based on analysis of finished leather samples up to a year after they are finished. In
the case of water-based coatings this becomes significant in that a major portion of
the VOC's are often high boiling compounds.
Four of the 5 spray booths have water curtains for control of particulate
emissions. The water used for the curtains is recycled until saturated, treated on site,
and then reused. The newest spray booth (Line 5) is a "dry" booth that does not have
a water curtain. A dual bank of dry filters control particulate emissions.
D. Emission Reduction Measures
Plant B has implemented two strategies to reduce VOC emissions. First, the
incinerator was installed as part of the initial startup of the facility. The incinerator is a
Reeco Re-therm, Model #VF-C-24000-85, with a capacity of 24,000 cfm. The installed
capital cost of this unit was about $800,000 in 1989. Efficiency tests have been
conducted on the incinerator and VOC destruction efficiencies of greater than 98
percent have been documented. The operating temperature of the incinerator is
maintained at about 1500 degrees fahrenheit. Supplemental fuel is used to maintain
the combustion temperature and to preheat the combustion chambers prior to venting
of the spray booths. When two spray booths are operating with applications of
solvent-based coatings, the incinerator does not require any supplemental fuel.
The Reeco incinerator is equipped with three ceramic packing beds to recoup
heat from the combustion flue gas. Heat energy is transferred from the hot
combustion flue gas to the ceramic packing and then transferred to the incinerator
feed. At any time, the combustion chamber flue gas is being routed through one bed
to heat the packing, the inlet stream to be incinerated is being passed through a
heated bed, and the third bed is idle.
Plant B is currently operating two shifts. Prior to starting production on the first
shift, the incinerator goes through a two hour warm up period to take the combustion
chamber temperature from 500 F up to the 1500 F operating temperature. At the end
of the second shift, the incinerator goes through a 3 hour cool down, from 1500 F to
500 F, and remains at an idle temperature of 500 F while the spray booths are not
being operated.
Plant B has also initiated a program to introduce water-based coatings
wherever possible, and to find formulations that reduce emissions of VOC and HAP's.
B-7
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For example, one base coat that previously had a VOC content of 10 percent along
with some HAP's, now has a VOC content of 1.74 percent with no HAP's. Conversely,
there are other coatings for which Plant B has been unable to find a suitable water-
based substitute. Antique coatings have VOC contents greater than 95 percent, while
most of their topcoats have VOC contents greater than 85 percent. At present, Plant
B feels that switching to all water-based coatings is not technically or economically
feasible. The performance of most water-based top coats evaluated is not adequate
to meet their client specifications. Additionally, Plant B estimates that the application of
some water-based coatings currently being considered could result in higher
emissions than applications of the controlled solvent-based coating. In the case of top
coats, the VOC content of water-based alternatives can be as high as 20 percent.
Through calculations, Plant B demonstrated that the use of such a top coat could
actually result in higher emissions than using a solvent based coating and routing the
spray booth and dryer exhaust to the incinerator. In the case of base coats, the
water-based coatings used by Plant B typically have 2 to 3 weight percent VOC in
their formulation.
Another effort to minimize VOC emissions is optimization of the spray booth
design and operation. Plant B continues to experiment with their spray booths to
maximize transfer efficiencies and minimize the loss of material through overspray and
bounce back. All of the spray booths are optically controlled. The leather passes
over infrared sensors that record the outline of the hide passing on the conveyor belt.
The spray guns turn off and on according to the outline of the hide.
Other factors also influence the efficiency of the spray booth. These factors
include conveyor speed, speed of the rotary spray arm, spray gun efficiency, and
operator training. Plant B continues to experiment with approaches to optimize
transfer efficiency, including the use of high-volume-low-pressure (HVLP) spray guns.
The rotary spray equipment at Plant B is equipped with 16 guns as opposed to 8 used
by many other companies.
E. Regulatory Compliance
As mentioned earlier, Plant B has taken a VOC limit of 250 tons per year to
avoid PSD review. Plant B is required to maintain annual VOC emissions on a rolling
12 month basis. For the calendar year 1992, Plant B indicated that VOC emissions
were about 120 tons.
F. Additional Information
In one state, the company is required to comply with a limit of 5.8 Ibs of VOC
per gallon. Most of the operations personnel at Plant B have been relocated from this
state to another location and in some cases they are still involved in the remaining
finishing operations. They were quick to point out the hinderance on operating
B-8
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flexibility posed by the state leather finishing rule. Instances where production was
dictated by compliance with the 5.8 Ibs VOC per gallon on a daily basis were cited. In
some instances production schedules were modified so that a water-based finish was
applied on a given day to offset the use of solvent-based material.
Plant B personnel pointed out that, as a company overall, they have reduced
VOC emissions from about 900 tons in 1989 to about 125 tons in 1992, with a
doubling in production. They also estimated that VOC emissions on a per hide basis
have dropped from 1.2 to 0.4 Ibs/hide.
B-9
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PLANTC
A. General
Plant C supplies finished leather to the automotive industry. According to Plant
C personnel, automotive upholstery is one of the most demanding leather products to
manufacture. The automotive industry requires that the leather meet strict quality
standards. These quality standards include specifications for color, rubfastness, light
resistance, and various durability requirements. The finished product typically must
meet 20-25 specifications. Plant C produces about 400-500 different leather
upholstery products, taking into account the variety of colors, textures, and other
specialty leathers produced at the plant.
B. Process Description
Raw cattle hides are first treated to remove hair and other undesirable elements.
Following this initial treatment, the hides are laterally split into two layers. The top half
is the grain side (or top side) while the bottom half is the flesh side or split. Plant C
processes the full hide as opposed to many leather finishing operations that process
sides (a full hide cut into longitudinal halves). The upper portions of the split hides
(top grain or full grain) are used to make upholstery leather while the splits are sold as
secondary products. Many of the splits produced at Plant C are used to make raw
hide dog bones.
From this point in the process, only the grain side of the hide is processed.
Following splitting, the hides are chrome tanned and then demoisturized. The tanned
hides are then mechanically treated to adjust the thickness of the raw material, and
then sorted by quality. Higher quality hides have fewer natural defects such as holes
and scratches. Plant C does not purchase hides that have been branded.
After the hides are sorted, they are retanned using dyes and fatliquors. The
dyes used at this stage form the base color for the final product. Before the leather is
finished, a number of intermediate steps are taken to dry, soften, and condition the
leather. At this point, the leather is ready for finishing. The finishing process involves
the application of coatings to enhance the quality of the leather and provide protection
of the product.
Plant C has a number of leather finishing lines used for both regular coating
operations and for research and development purposes. At present, all of the finishing
B-10
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lines use rotary spray coating applicators. Optical eye technology is used to minimize
overspray. The leather to be finished passes under an optical eye that reads the
outline of the leather. The rotary spray applicators are controlled by computer and
turn off and on according to the pattern of the leather.
C. Sources of Emissions
The sources of VOC emissions are primarily from the leather finishing process.
All leather coatings are mixed on-site using components purchased from various
suppliers. Although there is potential for some fugitive emissions from the mixing
process, Plant C uses mostly water based materials. The coatings mixing room was
observed during the site visit and there was little, if any, evidence of solvent odors in
the room.
Coatings are applied using rotary spray application equipment. Typically, three
finish coats are applied to each piece of leather. The actual number of coatings will
vary according to the requirements of individual leather products. The rotary spray
equipment is housed in a partially enclosed chamber. Coatings are applied from
airless spray guns located above the leather which moves through the spray chamber
on a conveyer belt. The conveyer belt is actually made up of a series of parallel wire
coils. A water bath is located below the conveyer belt and captures some of the
overspray.
VOC emissions from the leather finishing operation result from overspray,
"bounce-back" of coating from the leather, and from fugitive sources. Some emissions
may also result from the open mixing drums that feed coating to the spray guns, and
from wastewater generated by the water baths.
One additional source of VOC emissions at similar facilities could be the leather
retanning process. At Plant C, very little, if any VOC laden materials are used for
retanning. However, retanning may be a source of VOC in facilities that use VOC
containing oils for retanning. In addition, wastewater produced by the retanning
process could be a source of VOC, if VOC laden products are used in this process.
O. Emission Reduction Measures
Plant C has spent a great deal of resources in reducing the amount of VOC
used in their leather finishing process. As a result, the facility has reduced their VOC
emissions and emissions of hazardous air pollutants dramatically since 1988.
Conversion to water based coatings is the primary emission reduction measure
implemented by Plant C. Plant C claims that the transition to water based finishes has
reduced VOC emissions by 98 percent from 1988. In addition, there have been similar
B-11
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reductions in HAP emissions. Most of the toluene and xylene emissions reported in
the 1990 Toxic Release Inventory have been eliminated.
Data provided by Plant C indicate that total VOC emissions have been reduced
from 5.3 million pounds per year in 1988 to an estimated 0.26 million pounds for 1992.
Emissions data are also given in terms of pounds of VOC per 1,000 square feet of
processed hide, and for individual HAP's.
Plant C plans to continue to look for additional reductions in VOC emissions.
However, any additional reductions will be relatively minor compared to the reductions
achieved thus far. It will become more difficult to find further ways to reduce the
amount of VOC used in the coatings. There are applications where some VOC is"
needed in the coating. Plant C has also started to use roll coating machines to
supplement the rotary spray coating machines. The roll coating machines are
expected to have a higher transfer efficiency than the spray coating machines, thereby
reducing emissions resulting from overspray and bounce-back. However, there are
some limitations with the use of roll coating in producing automotive leather
upholstery. Roll coating usually imparts a thinner coating than desired in most leather
upholstery applications.
E. Regulatory Compliance
Plant C is located in a moderate non-attainment area for ozone. Currently,
Plant C is permitted as a major source of VOC. There is no specific rule for leather
finishing operations in the State. The State is in the process of developing a site-
specific rule for Plant C in the form of a consent order with the company.
B-12
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PLANTD
A. General
*
Plant D produces finished leather to be used primarily for footwear and other
fashion related products. The raw material is cattle hide, and approximately 50,000
sides of leather are processed weekly. A side of leather is a longitudinal half of a full
hide. The full hides are cut in two to facilitate processing. The raw hides are tanned
and finished at the site.
A wide range of finished leather is produced by Plant D. Accounting for the
differences in color, weight, physical characteristics, and grain textures, Plant D
produces about 8,000 products. The finishing process for each of these products is
specific, thereby making it difficult to characterize one specific leather finishing process
at the plant. All of the finishes used at the facility are mixed on-site using varying
combinations of pigments, dyes, binders, solvent, and other materials.
B. Process Description
Raw hides are first treated to remove hair and undesirable fats and oils using
water based chemicals. The hides are pickled and then chrome tanned to stabilize the
collagen fibers vital for leather production. Following these processes, the hides are
wrung out, cut into two sides, and split. The bottom or fleshy part of the split (referred
to as the "split") is sold to other manufacturers and the top part (referred to as the top
or full grain) is processed further. Following a mechanical demoisturizing process,
the hides are retanned and dyed using soluble dyes and fat liquor. The hides are then
placed in drying ovens to remove moisture and sent through mechanical operations to
soften the leather prior to finishing.
The finishing process varies according to the type of leather being produced.
In general, each side receives a base coat, a middle coat, and a top coat or finish
coat. At Plant D, the base and middle coats are mostly water based, while some of
the finish coats are solvent based coatings or emulsions. Some of the water based
finishing materials contain some VOC's, usually less than 10 percent by weight. The
water based emulsions contain higher VOC concentrations than the water based
coatings. The company is attempting to convert most of their finishing processes to
water based coatings. However, some product lines require a solvent based coating
or an emulsion to achieve the desired properties in the finished leather.
B-13
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C. Sources of VOC Emissions
The primary source of VOC emissions at the facility is the leather finishing process.
Emissions result from the application of coatings using various types of coating
technology. For example, rotary spray machines consist of multiple spray guns that apply
finishes to the leather as it passes on a conveyer belt. Emissions result from the solvent
flashing before the coating hits the surface of the leather, and overspray of material
(including bounce-back from the surface of the leather). The rotary spray coating
machines at Plant D are partially enclosed in a water wash booth under negative exhaust
pressure. Solvent vapors are collected in the spray areas and exhausted to the outside
ambient air. There are no vapor control systems on vents to the ambient air.
Small quantities of VOC emissions also result from mixing and formulating of
coatings, fugitive losses prior to application of the coatings, equipment cleaning, and
wastewater disposal. The mixing and formulation process was not observed during the
site visit. However, it seems probable that small losses occur during the mixing of the
coatings. Once a coating is mixed, it is transferred to the applications area in 30 gallon
drums. The coating material is pumped from the drums to the spray guns. The drums
are equipped with covers. However, the drums can remain partially or fully open to the
atmosphere during the coating process thereby creating the potential for small emissions
of VOC's.
Located beneath the conveyer belt that carries leather through the spray area is
a water bath. Some of the overspray of the coatings is deposited in this water which is
recirculated and then discharged as wastewater. This wastewater can be a secondary
source of VOC emissions.
Another source of air emissions is the tanning process. This process produces
small quantities of hydrogen sulfide and ammonia. However, this part of the operation
is not a significant contributor of VOC.
Leather finishing is accomplished using 8 roll coaters, 6 rotary spray coaters, and
one flow coater. All of the coatings are mixed on-site. The individual components of the
coatings are purchased from suppliers such as Rohm & Haas, Stahl, BASF, Ciba-Geigy,
and Prime Leather Finishes. Depending on the product, different coating formulations are
used. Each leather finishing process has a distinct formula that is kept in a computerized
file. Plant D uses this information to calculate the amount of solvent used on a daily
basis. Use of all toxic chemicals is tracked by Chemical Abstract Service (CAS) number
on a daily and annual basis.
Plant personnel estimate that 90 percent of the bottom and middle coats are water
based coatings. Most of the coatings containing the higher VOC quantities are used in
the top (or finish) coat.
B-14
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Toxic Release Inventory (TRI) data indicate that Plant D emitted over 45 tons of
hazardous air pollutants (HAP's) in 1990. Plant personnel verified this value, but indicated
that their emissions of both HAP's and VOC have been reduced since 1990. All emission
estimates at the facility are based on solvent usage. Emissions testing has not been
conducted.
D. Emission Reduction Measures
Reduction of VOC emissions has been achieved primarily through introduction of
water based coatings and process changes over the'past several years. Process
changes have included substitution of a roll coating machine for a curtain spray machine
and the application of oil coatings using heated oil. The use of heated oil has enabled
Plant D to use an oil coating having a lower VOC content. In addition, optical eye spray
technology is used to minimize overspray and use of coating material.
Specifically, one coating process in the plant was responsible for an estimated 35-
40 percent of the total VOC emissions. In this process, solvents were used to facilitate
oil penetration of the leather during coating. Plant D changed from a high solvent based
coating to a lower solvent based coating that was preheated prior to application to lower
viscosity. Plant personnel reported that these changes reduced VOC emissions from this
process by about 90 percent.
Plant D also has a policy of not allowing development of any leather product that
will exceed the daily limit set by the State. Any further reduction in VOC emissions will
be achieved through use of additional water based coatings.
E. Regulatory Compliance
Plant D is subject to the State rule for leather finishing operations. This rule limits
VOC emissions from leather coating facilities to 18.6 kilograms per 100 square meters
(38.0 pounds per 1000 square feet) of coated product calculated on a daily average.
Plant D meets this limit by using an "internal offset" system whereby products requiring
high VOC coatings are produced on the same day as those requiring low VOC, or water
based coatings. Since the limit is based on a summation of total VOC's emitted during
the day divided by the prorated surface area of leather coated during the same day, Plant
D can meet the limit on a daily basis by monitoring the types and amount of products
produced on a given day.
Compliance with the State regulation requires extensive recordkeeping. Plant D
keeps daily records of solvent usage and square footage of leather processed.
Plant personnel indicated that the State regulation was conducive to computerized
tracking of coatings formulations and production. They are in favor of the production
based limit because it allows them to use the internal system of offsetting to meet the
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regulation. This enables the company to produce a greater variety of products, including
some that require high VOC finishes, and allows Plant D to remain responsive to the
needs of the fashion industry.
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PLANTE
A. General
»
Plant E is exclusively a leather finishing plant. The finished leather produced at
Plant E is sold primarily to the furniture manufacturing industry.
B. Process Description
Tanned cattle hides are shipped to Plant E from the company's tannery, located
in another state. The hides are in the crust stage, having been chromed tanned,
retanned, colored, and dried at the tannery. After arrival, the hides are conditioned by
introducing controlled amounts of moisture. They are then softened in large dryers and
mechanically treated to achieve desired properties prior to finishing.
The finishing process involves application of 3 to 7 coats of finish on each hide,
depending on the desired characteristics of the specific product line. Plant E is equipped
with eight rotary spray booths for leather finishing. Each spray booth is followed by one
or two drying ovens. All of the spray booth and drying oven machinery was
manufactured by the Hampton Machine Company. Each of the spray booths is equipped
with optical eye controls to minimize overspray. Some of the spray booths are equipped
with 16 spray guns while others are eight gun booths. Only 8 guns are operating at any
given time in the 16-gun booths. Both high-volume-low-pressure (HVLP) and air assisted
spray guns are used at Plant E. One of the base coat booths is currently equipped with
HVLP guns. The other booths are equipped with air assisted airless guns.
Of the eight spray booths, five are used exclusively for applying water-based
coatings. One spray booth is used for both water and solvent-based coatings, and two
booths are used only for application of solvent-based coatings. The water-based coating
booths and the solvent-based coating booths are segregated in the plant for safety
reasons. The dryers used with the solvent-based spray booths are explosion proof.
There are five additional spray booths at the plant. Two of the spray booths are
for hand spraying of finishes and three booths are hand spraying operations for testings
coatings and .touch-up.
Following application of the base coats and top coats, the leather is moved to a
finishing room. In the finishing room, the leather can be embossed using high pressure
machinery and/or put through additional softening and conditioning operations. In
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addition, some leather are antiqued in the finishing area through hand application of
special coatings. Following all of the finishing operations, the feather is measured and
packed for shipping.
C. Sources of Emissions
All leather coatings are mixed on-site using components purchased from vendors.
The mixing room is a source of fugitive VOC emissions. Plant E has not attempted to
quantify emissions from the mixing room.
Coatings are applied using rotary spray application equipment. Typically, three to
five finish coats are applied to each piece of leather, with seven coatings being the
maximum number applied by Plant E. The actual number of coatings varies according
to the requirements of individual leather products. The rotary spray equipment is housed
in enclosed chambers. Coatings are applied from airless and\or HVLP spray guns
located above the leather which moves through the spray chamber on a parallel cable
conveyer.
VOC emissions from the leather finishing operation result from overspray, bounce-
back of coating from the leather, and from fugitive sources. Most of the VOC can be
expected to flash-off in the spray booths or in the drying ovens. All of the spray booths
and ovens are vented to the atmosphere. Source sampling was conducted on two spray
booths in 1989 in preparation for a prevention of significant deterioration (PSD) permit
application. This permit application effort was abandoned. There are no air pollution
control systems on the building ventilation system.
Plant E has a small distillation unit in the plant to recover solvent from waste
coatings and cleanup solvents. These waste streams and the plant wastewater are
segregated. Little, if any, VOC emissions are generated from the wastewater system.
Additional sources of fugitive emissions are the partially covered coatings drum
located at each spray booth, and the antiquing process in the finish room. The antiquing
process consists of manual application of a solvent based coating to the leather to
achieve an antique appearance.
D. Emission Reduction Measures
The only emission reduction strategy being employed by Plant E to control VOC's
is the transition to more water-based coatings. Plant E began using water-based coatings
in 1990. Prior to that time, most of their coating formulations were solvent-based. The
reductions from 1987 to 1990 were most likely a result of formulation changes by the
suppliers. According to plant personnel, the plant did not make a concerted effort to use
water-based materials until 1990.
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VOC emissions per hide began to increase following 1990. This increase was a
result of quality problems resulting from use of water-based coatings. Plant E was forced
to use more solvent-based materials to satisfy customer requirements. Plant personnel
noted that it is often difficult to achieve the aesthetic feels needed for furniture leather with
water-based materials. However, water-based technology is improving, and Plant E is
moving back to water-based materials, particularly for their Spring 1993 product line.
According to plant personnel, the driving force behind the move to water-based materials
is from within the industry itself. Minimization of solvent usage improves the working
environment in regards to both aesthetics and safety. Some of. the water-based coatings
have 1.5 to 5 percent VOC in the formulations, while the largest percentage of water-
based coatings have no VOC.
Other emission reduction efforts focus on optimization of the coatings application
process. Plant E has noticed some improvements in coating efficiency with the HVLP
guns, but this improvement is not documented. Currently, HVLP guns are used only on
the water-based lines.
Emissions data provided by the plant for 1991 show some reduction in emissions
of hazardous air pollutants (HAP's) compared to 1990. The 1990 Toxic Release Inventory
(TRI) indicated that Plant E emitted 223.5 tons of HAP's during that year: methyl ethyl
ketone (MEK)(73.5 tons); toluene (70.03 tons); methyl isobutyl ketone (MIK)(16.31 tons;
and cyclohexane (63.72 tons). According to plant data, 1991 emission of HAP's were
about 185 tons: MEK (6.83 tons); xylene (35.1 tons); MIK (49.31 tons); and toluene
(93.75 tons). Cyclohexane emissions were below the reporting threshold for 1991.
E. Regulatory Compliance
Plant E is located in an attainment area for ozone. Their current permit limits total
plant emissions to 702.3 tons per year on a rolling twelve month average. Emissions
estimates are based on consumption records kept by the plant. The current emissions
limit is the result of steps taken in 1989 to avoid PSD. When modifications were proposed
in that year, 39.9 tons per year was added to the existing annual emission limit. The plant
also complies with the State regulations by using solvent mixtures that are not
photochemically reactive as defined by the code.
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APPENDIX C
STATE AND LOCAL REGULATIONS AFFECTING LEATHER TANNING
AND FINISHING FACILITIES
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C.1 Introduction to Appendix C
This appendix contains the full text of existing and proposed regulations affecting
leather tanning and finishing facilities. Regulations from these six State and local agencies
are included: a) New Jersey; b) New York (with proposed amendments); c) Wisconsin;
d) Massachusetts (draft rule); e) Illinois (draft rule); and e) the Monterey Bay Unified Air
Pollution Control District (draft rule).
•»
For the Wisconsin rule, the full text of the technical support document for the
regulation is included in the appendix. This document provides a detailed rationale for
the format of the rule.
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State of New Jersey
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NEW JERSEY STATE DEPARTMENT OF ENVIRONMENTAL
PROTECTION AND ENERGY
NEW JERSEY ADMINISTRATIVE CODE
TITLE 7, CHAPTER 27
SUBCHAPTER 16
CONTROL AND PROHIBITION OF AIR POLLUTION BY
VOLATILE ORGANIC COMPOUNDS
Filed:
Effective:
Revision Promulgated:
Revision Effective:
Revision 'I'romulgated:
Revision Operative:
Revision Promulgated:
Revision Operative:
Revision Promulgated:
Revision Operative:
Revision Promulgated:
Revision Operative:
Revision Promulgated:
Revision Operative:
Revision Promulgated:
Revision Operative:
Revision Promulgated:
Revision Operative:
December 18, 1975
March 1, 1976
October 17, 1979
December 17, 1979
December 31, 1981
March 1, 1982
August 19, 1986
October 18, 1986
December 23, 1987
February 21, 1988
December 30, 1988
February 28, 1989
May 26, 1989
July 25, 1989
November 6, 1989
January 5, 1990
January 28, 1992
March 28, 1992
TABLE OF CONTENTS
7:27-16.1 Definitions
7:27-16.2 Storage of Volatile Organic Compounds
7:27-16.3 Transfer Operations
7:27-16.4 Open Top Tanks and Surface Cleaners
7:27-16.5 Surface Coating and Graphic Arts Operations
7:27-16.6 Source Operations Other Than Storage Tanks, Transfers, Open Top
Tanks, Surface Cleaners, and Surface Coaters and Graphic Arts
7:27-16.7 Cutback and Emulsified Asphalts
7:27-16.8 Petroleum Solvent Dry Cleaning Operations
7:27-16.9 Emission Information and Tests
7:27-16.10 Variances
7:27-16.11 Applicability
7:27-16.12 Exceptions
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/:2/-Lt>.3 ourrace coating ana grapaic arcs operations
(a) No person shall cause, suffer, allow, or permit the use of any surface
coating operation unless:
1. The VOC content of any surface coating formulation as applied does
not exceed the maximum allowable VOC content as specified in Table
3A, 3B, 3C, 3D or 3E; or
2. If more than one surface, coating formulation subject to the same
maximum allowable VOG content limit as set forth in the applicable
table is applied by a single surface coating operation, the daily
weighted mean of the VOC content of the coatings as applied does not
exceed the maximum allowable VOC content as set forth in Table 3A,
3B, 3C, 3D or 3E, as calculated ..using the following equation:
Daily mean VOC content »
where n » number of coatings, subject to the same maximum
allowable VOC content standard, applied in one
day;
i » subscript denoting an individual surface coating
formulation;
Cj » maximum actual VOC content per volume of each
coating (minus water) applied in one day, in
pounds per gallon or kilograms per liter; and
v^ = volume of each coating (minus water) applied in
one day, in gallons or liters; or
If the surface coating operation is served by VOC control apparatus:
i. The control apparatus prevents no less than 90 per'-'*"'- bv weight
of the VOC content in the surface coatine fortnuL-'' •• M-I-I ••'*'*
each hour from being discharged directlv or i^d'1 ' ' im-.. > 1,=,
outdoor atmosphere: or
ii. The VOC emissions from the surface coating operation are
controlled by the control apparatus so that the operation
results in an hourly VOC emission rate' no greater thari the
maximum allowable hourly emission rate calculated on a solids as
applied basis in accordance with the following equation:
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Maximum allowable hourly rate = (L-y/d)(z)(x)/(1-x/d)
whire x = maximum allowable VOC content per volume of coating
(minus water), in pounds per gallon (Ib/gal) or
kilograms per liter (kg/1) as set forth in Table 3A,
3B, 3C, 3D, or 3E of this section;
d = density of the VOC of the applied surface coating
formulation, in pounds per gallon (Ib/gal) or
kilograms per liter (kg/1);
y = .VOC content of the applied surface coating formulation
(minus water) in .pounds per gallon (Ib/gal) or
kilograms per liter (kg/1); and
z = volume of the coating (minus water) applied per hour
in gallons per hour (gal/hr) or liters per hour
(1/hr); or
iii. For a surface coating operation that applies more than one
surface coating formulation subject to the same maximum
allowable VOC content »limit as set forth in the applicable
table, the control apparatus collects and prevents VOC from
being discharged into the outdoor atmosphere so that the actual
daily emissions are less than the allowable daily emissions as
calculated below:
Actual daily emissions = (1-*? rTy )(VOCa)(V)
where: VOCa = daily mean VpC content of the surface
coating formulations as calculated by 2
above;
V = total daily volume of the surface coating
formulations, as applied;
= capture efficiency, i.e. the ratio of the
VOC collected by the control apparatus to
the VOC in the surface coating formulations
as applied, as determined by a method
approved by the Department and EPA; and
= destruction efficiency of the cqntrol
apparatus, i.e. the ratio of the VOC
prevented from being dischare0-' '••'• ''"-•
outdoor atmosphere to th<; "'»* . •• i i <•• i •>-! i-v
the control apparatus, as de|:9'-min"rl ^v -••>
method approved by the Department -and EPA:
and
Allowable daily emissions = (l-VOC /d)(V)(x)/(l-x/d)
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where x = maximum allowable VOC content per volume of coating
(minus water), in pounds per gallon (Ib/gal) or
kilograms per liter (kg/L) as set forth in Table 3A,
3B, 3C, 3D, or 3E of this section;
d = density of the VOC of the applied surface coating
formulations in pounds per gallon (Ib/gal) or
kilograms per liter (kg/1);
. V = total daily volume, in gallons or liters, of the
surface coating formulations (minus water) as applied
per day; and
VOCa = daily mean VOC content of the applied surface coating
formulations as calculated by 2 above; or
4. Until March 28, 1994, the surface coating operation is included in a
mathematical combination of sources which was approved by the
Department prior to March 28, 1992.
(b) No person shall cause, suffer, allow, or permit the installation of any
surface coating or graphic arts »operation to apply a surface coating
formulation which does not contain water deliberately added in a planned
proportion unless a coating application system having a transfer
efficiency of 60 percent or greater, or as otherwise approved by the
Department, is used. *
(c) The provisions of (a) and (b) above and (f), (g), and (h) below shall not
apply to any individual surface coating or graphic arts operation in which
the total surface coating formulations containing VOC are applied:
1. Prior to June 15, 1990, at rates not in excess of one gallon per hour
and five gallons per day;
2. As of June 15, 1990 and continuously thereafter, at rates not in
excess of one half gallon per hour and two and one half gallons per
day; or
3. For the purpose of developing new coatings or new coating equipment,
or for the purpose of performing research preceding such development
provided such formulations are applied at rates not in excess of two
gallons per hour and three gallons per day.
(d) Any person responsible for any automobile or light dutv truck surface
coating operation may, as an alternative to ^"r'ving. i •> >•• ' •
above, with the content limits set ^orth in TaM• -
coating formulations, provided that the transfer efficiency ot the spr.iy
coating operation is determined in accordance with a method approved by
the Department and the EPA.
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TABLE 3A
MAXIMUPI ALLOWABLE VOC CONTENT IN COATINGS FOR AUTOMOBILE
AND LIGHT DUTY TRUCK SURFACE COATING OPERATIONS
Tvoe of Operation
Maximum Allowable
VOC Content per Volume
of Coating (minus water)
Final
Compliance Date
Prime
Electrophoretic dip
prime Spray prime
Topcoat
Spray topcoat
Repair
Custom Topcoating
Refinishing
Base coat
Clear coat
All others
Pounds Per
Gallon
1.2
2.8
2.8
4.8
5.0
6.0
4.4
5.0
Kilograms
Per Liter
0.14
0.34
0.34
0.58
0.60
0.75
0.54
0.60
December 31, 1982
December 31, 1984
December 31, 1986
December 31, 1986
June 15, 1990
June 15, 1990
June 15, 1990
June 15, 1990
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TABLE 3B
MAXIMUM ALLOWABLE VOC CONTENT IN COATINGS
FOR MISCELLANEOUS SURFACE COATING OPERATIONS
Type of Operation
Maximum Allowable
VOC Content per Volume
of Coating (minus water)
Group I
Can Coating
Sheet basecoat
Two-piece can exterior
Two- & three-piece can
interior body spray,
two-piece and exterior
Side-seam spray
End sealing compound
i
Coil Coating
Fabric Coating
Vinyl Coating
Paper Coating
Metal Furniture Coating
Magnet Wire Coating
Large Appliance Coating
Miscellaneous Metal Parts
and Products
Clear coating
Air-dried coating
Extreme performance coating
All other coatings
Flat Wood Paneling
Printed hardwood plywood panels
and particleboard panels
Natural finish hardwood plywood
Hardboard panels
Group II
Leather Coating
Urethane Coating
Tablet Coating
Glass Coating
Pounds per
Gallon
2.8
4.2
5.5
3.7
2.6
2.9
3.8
2.9
3.0
1.7
2.8
4.3
3.5
3.5
3.0
2.7
3.3
3.6
5.8
3.8
5.5
3.0
Kilograms
per Liter
0.34
0.51
0.66
0.44
0.31
0.35
0.45
0.35
0.36
0.20
0.34
0.52
0.42
0.42
0.36
0.32
0.40
0.43
0. frh
0.36
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TABLE 3C
ALTERNATIVE MAXIMUM ALLOWABLE VOC CONTENT IN COATINGS WITH MINIMUM
TRANSFER EFFICIENCIES REQUIRED FOR SPRAY COATING OPERATIONS
Maximum Allowable VOC Content
per Volume of Coating Minimum Transfer
_ (minus water) _ Efficiency Required
Pounds per Kilograms
Gallon per Liter
3.0 0.36 -. 34
3.2 0.38 - 37
3.4 0.41 42
3.6 0.43 " 47
3.8 0.46 52
4.0 0.48 58
4.2 0.50 65
NOTE: Each combination of VOC consent, and transfer efficiency in Table 3C
is equivalent to a daily emission of 15.1 pounds of VOC per gallon of
solids deposited, minus water. Verification of this equivalent
emission rate using the methods prescribed in the "Protocol for
Determining the Daily Volatile Organic Compound Emission Rate of
Automobile and Light Duty Truck Topcoat Operations" (EPA
450/3-88-018) shall satisfy compliance with Table 3C.
TABLE 3D
MAXIMUM ALLOWABLE VOC CONTENT IN COATINGS
FOR GRAPHIC ARTS SOURCE OPERATIONS
Control Criterion
For formulations that contain water: Maximum Allowable volume percent VOC in
volatile fraction of coatings (VOC plus
water) as applied.
Volume Percent
25.0
or
For formulations that do not
contain water: Maximum Allowable VOC Content per
volume of ; formulation (minus water)
Pounds per Kilograms
Gallon per Liter
2.9 0.35
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TABLE 3E
MAXIMUM ALLOWABLE VOC CONTENT IN COATINGS FOR
WOOD FURNITURE SURFACE COATING OPERATIONS
Type of Surface
Coating Formulation
Maximum Allowable
VOC Content per Volume
of Coating (minus water)
Semitransparent stain
Wash coat
Opaque stain
Sealer
Pigraented coat
Clear topcoat
Pounds per
Gallon
6.8
6.1
4.7
5.6
5.0
5.6
Kilograms
per Liter
0.82
0.73
0.56
0. 6 7
0.60
0.67
(e) Any person responsible for any metal furniture or large appliance surface
coating operation may, as an alternative to complying with the applicable
maximum allowable VOC content limits per volume of coating (minus water)
set forth in Group I of Table 3B, pursuant to (a)l above, apply to the
Department for an alternative maximum allowable VOC content limit per
volume of coating, provided such person can demonstrate to the
satisfaction of the Department and the EPA that the surface coating
formulation is applied at transfer efficiency of greater than 60 percent.
(f) Any person responsible for a rotogravure, flexographic, or fabric printing
operation may, as an alternative to complying with the requirements set
forth in Table 3D, pursuant to (a)l above, install and use control
apparatus which:
I. Collects at least 75 percent by volume of the source gas emitted from
a rotogravure printing operation, including associated dryers, and
prevents from being discharged into the outdoor atmosphere at least
90 percent by volume of the VOC collected on an hourly basis;
2. Collects at least 7"0 percent by volume of the source gas emitted from
a flexographic printing operation, including associated dryers, and
prevents from being discharged into the outdoor atmosphere at least
90 percent by volume of the VOC collected on an hourly basis; or
3. Collects at least 70 percent by --^Lume of tho =n,,v-° c. .••••> ,i i, .,,,
a fabric printing operation. includinc a?<=°' i->'<>- • •" • .
prevents from beir.e discharged :.nto the outdoor a tm^-r1'0 • - "• >•-!-'
90 percent by volume of the VOC collected on an hourly basis.
(g) Notwithstanding the provisions of (a)3.ii and (a)4 above, any person
responsible for a tablet coating operation that uses a surface coating
formulation that does not comply with the maximum allowable VOC content
limits per volume of :cating (minus water) set forth in Table 3B, Group
II, shall install and use control apparatus which prevents no Less than 30
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t/ti-jeu- „>• weignL ui w^e ^^^ concent: in cne surrace coating tormuiati.cn as
applied each-"hour from being discharged directly or indirectly into the
outdoor atmosphere.
(h) Any person responsible for a wood furniture surface coating operation
shall comply with the following requirements:
1. At a facility emitting less than 50 tons (45.36 megagrams) of VOC per
year, each surface coating formulation specified in Table 3E shall be
applied using airless, air-assisted airless, or heated airless spray
techniques, or another application method approved by the Department
and the EPA as having a transfer efficiency of at least 40 percent; or
2. At a facility emitting 50 tons (45.36 megagrams) of VOC or greater
per year, each surface coating formulation specified in Table 3E
shall be applied using airless, air-assisted airless, heated airless,
electrostatic spray techniques, or flat line processes, or another
application method approved by the Department and the EPA as having a
transfer efficiency of at least 65 percent.
(i.) Any person responsible for an automobile or light duty truck surface
coating operation subject to a. VOC content limit for custom topcoating or
refinishing set forth in Table 3A of this section shall comply with the
following schedule:
1. By July 1, 1989, a plan must be submitted to the Assistant Director,
Enforcement Element, New Jersey Department of Environmental
Protection, CN 027, Trenton, NJ 08625, for approval describing the
measures which will be applied in order to achieve compliance. The
plan submittal shall include:
i. Completed applications for all "Permits to Construct, Install,
or Alter Control Apparatus or Equipment" and "Certificates to
Operate Control Apparatus or Equipment" required by N.J.A.C.
7:27-8; and
ii. Documentation of the rates of application of surface coating
formulations in surface coating operations excluded under the
provisions of (c) above and (k) below; and
iii. Details of production rate changes or process modifications for
which no "Permits to Construct, Install, or Alter Control
.Apparatus or Equipment" are required.
2. By July 1, 1989, and by the first day of everv fourth month
thereafter, persons subject to an emissi^-' Limit-i*-- • •.,'.,, i .....
topcoating or refinishing usine surface ••••?':ine '-of
measure 'for complying with the provision? of ' 9 > ?b^"~ 'i'M <=uhnn<
detailed reports describing the progress being made with spec if i-
coating manufacturers and suppliers toward the development of
suitable .formulations. The reports shall b-e sent to the Assistant
Director, Enforcement Element, at the address in (i)l above.
3. By no later than six months prior to the applicable final compliance
date set forth in Table 3A, construction or installation of equipment
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and control apparatus, in accordance with the approved plan, shall
commence.
U. By the applicable final compliance date set forth in Table 3A,
compliance with this Section shall be achieved.
(j) Any person responsible for a surface coating.operation subject to a VOC
content limit set -forth in Table 3B, Group II for leather coating,
urethane coating, tablet coating, glass coating; in Table 3D for fabric or
urethane printing operations; or in Table 3E for wood furniture coating,
shall comply with the following schedule:
1. By January 30, 1987, a plan must be submitted to the Department for
approval describing the measures which will be applied in order to
achieve compliance. The plan submittal shall include:
i. Completed applications for all "Permits to Construct, Install,
or Alter Control Apparatus or Equipment" and "Certificates to
Operate Control Apparatus or Equipment" as required by N.J.A.C.
7:27-8;
ii. Completed applications, if relevant, for the mathematical
combination of source gases;
iii. Documentation of the rates of application of surface coating
formulations in surface coating operations excluded under the
provisions of (c) above; and
iv. Details of production rate changes or process modifications for
which no "Permits to Construct, Install, or Alter Control
Apparatus or Equipment" are required.
2. By 'January 1, 1987 and by the first day of every fourth month
thereafter, persons using surface coating reformulation as a measure
for complying with the provisions of (a) or (h) above shall submit
detailed reports describing the progress being made with specific
surface coating manufacturers and suppliers toward the development of
suitable formulations.
3. By May 1, 1987, construction or installation of equipment and control
apparatus, in accordance with the approved plan shall commence.
U. By December 31, 1987, compliance with this section shall be achieved.
(k) The provisions of this section shall not apply to:
1. The surface coatine of aircraft and •• >"> '••• -
exclusive of parts coated pric". 10 ins tall?h. i'?" or gs = °inM"-
2. The refinishing of automobiles, if coating use is less than ^"
gallons (189 liters) per week;
3. The customized topcoating of automobiles and trucks, if coating use
is less than ^8 gallons (182 liters) per week; and
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4. The on-site coating of assembled structures such as, but not Limited
to, equipment used for manufacturing processes, storage tanks,
bridges, and swjjnming pools.
(1) Any person responsible for the emission of any VOC from any surface
coating operation subject to this section applying only surface coating
formulations which are subject to and conform with the applicable VOC
content limit set forth in Table 3A, 3B, 3C, 3D, or 3E shall maintain
records of the VOC content of each surface coating formulation (minus
water) as applied, in pounds of VOC per gallon of coating or kilograms of
VOC per liter of coating; the percent by weight of any exempt organic
substance; and the daily volume of each surface coating formulation
applied.
(m) Any person responsible for any surface coating operation, which is subject
to this section and which uses one or more surface - coating formulations
which do not conform with the -applicable VOC content limit set forth in
Table 3A, 3B, 3C, 3D, or 3E, shall maintain the following records:
1. On a daily basis, specification of the following for each surface
coating formulation as applied:
i. The number of hours applied;
ii. The volume applied;
iii. The density of the formulation;
iv. The density of the VOC in the formulation;
v. The percent by weight of the VOC in the formulation;
vi. The percent by weight of any exempt organic substance in the
formulation; and
vii. The percent by weight of any water in the formulation;
2. For any surface coating operation that has a thermal oxidizer used to
control the emission of VOC, record on a continuous basis or at a
frequency approved in writing by the Department the operating
temperature at the exit of the combustion chamber and the carbon
monoxide concentration in the flue gas emitted to the outdoor
atmosphere;
3. For any surface coating operation that has a control ?i?p?r?ituj: ».?inz
carbon or other adsorptive material to coot-?' ^Ho ami- •• r "<"••
i. Record on a continuous basis or ?h. * freq"e<"; -MM" ^V-°H
writing by the Department the concentration of tlie total VOL m
the flue gas emitted to the outdoor atmosphere; or
ii. Record the date and time the carbon or other adsorptive material
used in the control apparatus is regenerated or replaced; and
maintain any other information required to document whether the
control apparatus is being used and maintained in accordance
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with the manufacturer's recommended procedures. The
manufacturer's recommendations for use and maintenance are to be
readily available on the operating premises, and the person
responsible for the surface coating operation shall provide
these to the Department upon request; and
4. Upon request of the Department and at a frequency specified by the
Department, record any other operation parameter relevant to the
prevention or control of air contaminant emissions from the surface
coating operation or control apparatus.
(n) All or part of the information documenting the composition of a surface
coating formulation as required by (1) or (m) above may be in the form of
standard formulation sheets, material safety data sheets, the results of
1 analytical tests, or another form provided that the required information
can be readily extracted.
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State of New York
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THIS DOCUMENT IS BASED ON THE PROPOSED AMENDMENTS INCLUDED IN THE
EXPRESS TERMS APPROVED BY THE ENVIRONMENTAL BOARD ON 1-29-93.
(3-30-93:JRC)
PART 228
SURFACE COATING PROCESSES
228.1 Applicability and compliance
228.2 Definitions
228.3 Volatile organic compound emission control requirements
228.4 Opacity
228.5 Reports, recordkeeping, sampling and analysis
228.6 Prohibition of sale or specification
228.7 Table 1
228.8 Table 2
228.9 Products regulated
228.10 Handling, storage and disposal of volatile organic
compounds(VOC)
Section 228.1 Applicability and compliance, (a) Any
owner or operator of a facility involving a coating line
described in table 1 of section 228.7 or in table 2 of section
228.8 of this Part and which meets the current applicability
criteria, must when applying for a permit to construct or a
certificate to operate as required.by Part 201(Permits and
Certificates), include with the application for a permit to
construct or certificate to operate, the method or methods which
will be used to comply with the requirements of this Part.
(b) Except as provided in section 228.l(h) of
this Part, any owner or operator of a facility involving a
coating line described in table 1 of section 228.7 or in table 2
of section 228.8 of this Part, which is located in the New York
City metropolitan area, must comply with this Part according to
the following schedule.
(1) Except as provided in 228.1(b)(2), any owner
or operator of a facility involving a coating line described in
table 1 of section 228.7 of this Part which was constructed on or
prior to August 23, 1979 must have demonstrated compliance with
this Part not later than May 10, 1984.
(2) Any owner or operator of a facility involving
a coating line described in table 1 of section 228.7 of this
Part, who utilized less than five gallons per day of coating
material on a facility-wide basis and had valid certificates to
operate, must have demonstrated compliance with this Part not
later than May 15, 1991.
(3) Any owner or operator of a facility involving
a coating line described in table 1 of section 228.7 of this Part
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which was constructed after May 10, 1981 must have demonstrated
compliance with this Part upon start-up.
(4) Any owner or operator of a facility involving
a coating line described in table 2 of section 228.8 of this Part
which was constructed on or before September 1, 1988 must have
demonstrated compliance with this Part not later than
May 15, 1991.
(5) Any owner or operator of a facility involving
a coating line described in table 2 of section 228.8 of this Part
which was constructed after September 1,^1988 must have
demonstrated compliance with this Part upon start-up.
(c) Except as provided in section 22&.l(h) of
this Part, any owner or operator of a facility involving a
coating line described in table l of section 228.7 or in table 2
of section 228.8 of this Part, which is located in Lower Orange
County metropolitan area must comply with this Part according to
the following schedule.
(1) Any owner or operator of a facility
involving a coating line described in table 1 of section 228.7 of
this Part which was constructed on or before August 23, 1979 for
which the annual potential to emit volatile organic compounds
from all sources regardless of process type, but excluding
combustion installations, at the facility equal or exceed 100
tons must have demonstrated compliance with this Part not later
than May 10, 1984.
(2) Any owner or operator of a facility involving
a coating line described in table 1 of section 228.7 of this Part
which was constructed after May, 10, 1981 for which the annual
potential to emit volatile organic compounds from all sources
regardless of process type, but excluding combustion
installations, at the facility equal or exceed 100 tons must have
demonstrated compliance with this Part upon start-up.
(3) Any owner or operator of a facility involving
a coating line described in table 1 of section 228.7 for which
the annual potential to emit volatile organic compounds from all
sources regardless of process type, but excluding combustion
installations, at the facility equal or exceed 10 tons, or a
coating line described in table 2 of section 228.8 of this Fart,
for which the annual potential to emit volatile organic compounds
from all sources regardless of process type, but excluding
combustion installations at the facility equal or exceed 25 tons,
must:
(i) submit a compliance plan to the Department of
Environmental Conservation by November 15, 1993 which contains a
schedule of the steps necessary for the facility to achieve
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compliance with this Part or limit its annual potential to emit
below the applicability criteria and the dates by which each step
will be completed;
(ii) be in compliance with this Part or have had
its permits modified to limit its annual potential to emit below
the applicability criteria by June 1, 1995; and
(iii) maintain the VOC control requirements and
compliance schedule included in any permit, regulation, rule,
administrative order, or any judicial order,, until compliance
with the provisions of this Part is demonstrated to the
satisfaction of the commissioner.
(4) Any owner or operator of a facility involving
a coating line described in table 1 of 228.7 or table 2 of
section 228.8 which is constructed after March 1, 1993 and which
meets the applicability criteria specified in 228.1(c)(3), must
demonstrate compliance with this Part upon start-up.
(d) Except as provided in section 228.l(h) of
this Part, any owner or operator of a facility involving a
coating line described in table 1 of section 228.7 or in table 2
of section 228.8 of this Part, which is located outside the New
York City metropolitan area and Lower Orange County metropolitan
area, must comply with this Part according to the following
schedule.
(1) Any owner or operator of a facility involving
a coating line described in table 1 of section 228.7 of this Part
which was constructed on or before August 23, 1979 and is located
in the counties of Albany, Cayuga, Columbia, Dutchess, Erie,
Genesee, Greene, Livingston, Monroe, Niagara, Onondaga, Ontario,
Orange (outside the Lower Orange County metropolitan area)
Orleans, Putnam, Rensselaer, Saratoga (limited to the towns of
Clifton Park and Halfmoon, the city of Mechanicville, and the
town and village of Waterford), Schenectady, Seneca, Ulster,
Wayne, Wyoming, or Yates for which the annual potential to emit
volatile organic compounds from all sources regardless of process
type, but excluding combustion installations, at the facility
equal or exceed 100 tons must have been in compliance with this
Part not later than May 10, 1984.
(2) Any owner or operator of a facility involving
a coating line described in table 1 of section 228.7 of this Part
which was constructed after May 10, 1981 and is located outside
the New York City metropolitan area and Lower Orange County
metropolitan area for which the annual potential to emit volatile
organic compounds from all sources regardless of process type,
but excluding combustion installations, at the facility equal or
exceed 100 tons must have demonstrated compliance with this Part
upon start-up.
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(3) Any owner or operator of a facility involving
a coating line described in table 1 of section 228.7 for which
the annual potential to emit volatile organic compounds from all
sources regardless of process type, but excluding combustion
installations, at the facility equal or exceed 10 tons, or a
coating line described in table 2 of section 228.8 of this Part
for which the annual potential to emit volatile organic compounds
from all sources regardless of process type, but excluding
combustion installations, at the facility equal or exceed 50 tons
must:
(i) submit a compliance plan to the Department of
Environmental Conservation by November 15, 1993 which contains a
schedule of the steps necessary for the facility to achieve
compliance with this Part or reduce its annual potential to emit
below the applicability criteria and the dates by which each step
will be completed;
(ii) be in compliance with this Part or have had
its permits modified to limit its annual potential to emit below
the applicability criteria by June 1, 1995; and
(iii) maintain the VOC control requirements and
compliance schedule included in any permit, regulation, rule,
administrative order, or any judicial order, until compliance
with the provisions of this Part is demonstrated to the
satisfaction of the commissioner.
(4) Any owner or operator of a facility involving
a coating line described in table 1 of 228.7 or table 2 of
section 228.8 which is constructed after March 1, 1993 and which
meets the applicability criteria specified in 228.1(d)(3), must
demonstrate compliance with this Part upon start-up.
(e) This Part previously contained a facility-
wide emission reduction (bubble) plan involving processes covered
by the provisions of this Part to reduce emissions to the level
which would be allowed if a surface coating complied with the
limits specified in table 1 of section 228.7 of this Part. Any
owner or operator of a facility which has operated in accordance
with a facility-wide emission reduction plan approved by the
commissioner must:
(1) submit a compliance plan to the Department of
Environmental Conservation by November 15, 1993 which contains a
schedule of the steps necessary for the facility to achieve
compliance with this Part and the dates by which each step will
be completed;
(2) be in compliance with this Part by June 1,
1995; and
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(3) maintain the VOC control requirements and
compliance schedule included in any permit, regulation, rule,
administrative order, or any judicial order, until compliance
with the provisions of this Part is demonstrated to the
satisfaction of the commissioner.
(f) Any owner or operator of a surface coating
process, which is not regulated under this Part, shall comply
with all other applicable Parts of this Subchapter.
(g) Any coating line that is subject to the
provisions of this Part, will remain subject to these provisions
even if the annual potential to emit volatile organic compounds
from the facility later fall below the applicability criteria.
(h) This Part does not apply to the following
coatings:
(1) research and development processes involving
surface coating which produce a product for study rather than
eventual sale;
(2) adhesives and materials used to prepare a
surface for adhesion where the coating is manually applied
without the use of mechanical means;
(3) sealant or filler used to seal or fill seams,
joints, holes and minor imperfections of the surface where the
coating is manually applied without the use of mechanical means;
(4) anti-corrosive wax and heat resistant anti-
corrosive coatings used in the automobile manufacturing industry
to protect door opening seam areas and floor pan areas,
respectively;
(5) clear or translucent coatings, applied to
clear or translucent plastic substrates which are utilized in the
manufacture of backlighted outdoor signs;
(6) coatings which are applied manually with a
brush, roller, or an aerosol spray can;
(7) aerospace coatings which are utilized for
pretreatment, adhesive bonding primers, flight testing, fuel
tanks, electric/radiation effects, space vehicles and temporary
mechanical maskant/high temperature heat treatment.
(8) clear and pearlescent coatings applied to
plastic fashion items such as beads, buttons, buckles or other
plastic accessories used in the fashion industry;
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(9) coatings which are applied to optical lens at
facilities whose annual potential to emit volatile organic
compounds are less than 10 tons;
(10) reflective coatings applied to highway cones;
(11) electromagnetic interference/radio frequency
interference (EMI/RFI) coatings applied on plastic electronic
equipment to provide shielding against electromagnetic
interference, radio frequency interference, or static charge; or
(12) electric dissipating.coatings that rapidly
dissipate a high-voltage electric charge applied on plastic
parts.
(13) low-use specialty coatings where the
plantwide total annual usage is equal to or less than 55 gallons
provided that:
(i) each specialty coating must be approved by the
commissioner's representative prior to application;
(ii) records must be maintained on an as used
basis in a format acceptable to the commissioner that document
the annual usage;
(iii) the annual potential to emit from low-use
specialty coatings does not exceed 5 percent of the facility's
total annual potential to emit; and
(iv) the facility's permits are modified to
identify any coating(s) approved by the commissioner's
representative which are exempt from this Part.
228.2 Definitions, (a) For the purpose of this
Part, the general definitions of Part 200 will apply.
(b) For the purpose of this Part, the following
definitions also apply:
(1) Annual. Refers to a period of time based upon
a calendar year commencing January 1st and terminating midnight
December 31st.
(2) Capture system. All the equipment including,
but not limited to, hoods, ducts, fans, booths, ovens or dryers
that contains, collects, and transports an air pollutant to a
control device.
(3) Clear coating. A coating which lacks color
and opacity or is transparent and uses the undercoat as a
reflectant base or under-tone color.
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(4) Clear topcoat. The final coating which
contains binders but not opaque pigments and which is
specifically formulated to form a transparent or translucent
solid protective film 'on wood furniture.
(5) Coating line. The application of one or more
surface coatings, using one or more applicators, together with
any associated drying or curing areas. A single coating line ends
after drying or curing and before other surface coatings are
applied. For any web coating line this term means an entire
coating application system, including any associated drying ovens
or areas located between an unwind station and rewind station,
that is used to . apply surface coatings onto a continuous strip or
web. It is not necessary to have an oven or flash area in order
to be included in this definition.
(6) Coating system. A series of surface coatings
applied in subsequent layers at the same coating line for
protective, decorative, or functional purposes. Each layer of the
coating system must be dependent upon the previously applied to
produce a marketable product. The coatings must be applied
simultaneously at multiple coating stations within the same
coating line.
(7) Container. Any portable device in which a
material is stored, transported, or otherwise handled.
(8) Excluded VOC. Any of the compounds expressly
excluded from the definition of volatile organic compound in
section 200.1 of this Title.
(9) Extreme performance coating. A coating
formulated for and exposed to harsh environmental conditions,
including but not limited to continuous exposure to outside
weather, temperatures consistently above 95° C, temperatures
consistently below 0° C, solvents, detergents, abrasives,
scouring agents or corrosive gases and fluids.
(10) Lower Orange County metropolitan area. The
area including the towns of Blooming Grove, Chester, Highlands,
Monroe, Tuxedo, Warwick and Woodbury.
(11) Maximum permitted pounds of volatile organic
compounds (VOC) per gallon of coating, minus water and excluded
VOC, at application. The permissible quantity of volatile
organic compounds per gallon of coating minus water and excluded
VOC, at application as specified in tables 1 and 2 of this Part.
The actual VOC content of the as applied coating is calculated as
follows:
(VOC) a = (Dc)a ffWv^a - fWw)a -.(Wela)
1 - ((Vw)a + (Ve)a)
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where:
(VOC)a = VOC content of "as applied" coating, expressed
as a mass of VOC, in pounds, per volume of coating, in gallons,
minus water and excluded VOC
(Dc)a = coating density as applied, in pounds per
gallon
(Wv) a = the weight fraction of total volatiles in the
coating, as applied
(Ww)a = the weight fraction of,water in the coating, as
applied
(Vw) a = the volume fraction of water in the coating, -as
applied
(We)a = the weight fraction of excluded VOC in the
coating, as applied
(Ve) a = the volume fraction of excluded VOC in the
coating, as applied
(12) Natural finish hardwood plywood panels.
Panels whose original grain pattern, frequently supplemented by
fillers or toners, is enhanced by essentially transparent
finishes.
(13) New York City metropolitan area. All of the
city of New York, and Nassau, Suffolk, Westchester and Rockland
Counties.
(14) Opaque stain. Any stain that contains
pigments but which is not classified as a semitransparent stain,
including stains, glazes, and other opaque materials applied to
wood surfaces.
(15) Overall removal efficiency. The total
reduction of volatile organic compound emissions considering the
efficiency of both the capture system and of the subsequent
destruction and/or removal of these air contaminants by the
control equipment prior to their release into the atmosphere.
(16) Pigmented coat. Opaque coatings, applied
either as an undercoat or a topcoat, that contain binders and
colored pigments and are formulated to conceal the wood surface.
(17) Plastic parts. Plastic parts are parts made
from a substance that has been formed from a resin through the
application of heat, pressure or both. They include but are not
limited to thermoplastics and thermosets such as acrylonitrile-
butadiene-styrene (ABS), acrylic (AC), cellulosics, nylon,
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polycarbonatevinyls, xenoy, melamines, polyester (BMC), reaction
injection molding (RIM), polyurethanes (PU). This also includes
composites such as fiberglass-reinforced plastics (FPR), which
are comprised of thermosetting or thermoplastic resins and
fibers, filaments, or fine powders.
(18) Potential to emit. The maximum capacity of an
air contamination source to emit any air contaminant under its
physical and operational design. Any physical or operational
limitation on the capacity of the facility or air contamination
source to emit any air contaminant, including air pollution
control equipment and/or restriction on the hours of operation,
or type of material combusted, .^stored, or processed, shall be
treated as part of the design only if the limitation is contained
in enforceable permit conditions. Fugitive emissions, to the
extent that they are quantifiable, are included in determining
the potential to emit.
(19) Printed interior panels. Panels whose grain
or natural surface is obscured by fillers and basecoats upon
which a simulated grain or decorative pattern is printed.
(20) Sealer. A coating which contains binders
that seal a wood surface prior to application of a subsequent
coating.
(21) Semitransparent stain. Stains that contain
dyes and/or semitransparent pigments and are formulated to
enhance wood grain and to change the color of the surface, but
not to conceal the surface; including sap stain, toner, nongrain
raising stain, pad stain, spatter stain, and other
semitransparent stains.
(22) Solids as applied. Utilizing the actual
volume of coating solids applied, compliance is determined as
follows:
{lVn)al, ) f(l. overall removal efficiency) jVOOa) - f(VOO£\> =
f \\ ivs*-/ \ (vs)c/j
(+) Ibs. over allowable
(0) compliance
(') Ibs, under allowable
where:
V = the volume of actual coating used, gallons
(Vn)a = volume fraction solids in the actual
coating
(VOC)a = VOC content of "as applied" coating,
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expressed as a mass of VOC, in pounds,
per volume of coating , in gallons, minus
water and excluded VOC
(VOC)c = mass of VOC in a volume of solids and VOC
for complying coating, pounds VOC/gallon
d(VOC)a = density of volatile organic content
(total volatiles minus exempt solvents
and water) as applied, pounds per
gallon and,
(Vs)a = 1 - fVOC^a (Vs)c = 1 - (VOC) c
d(VOC)a d(VOC)a
(23) Solvent. A substance that is liquid at
standard conditions and is used to dissolve or dilute another
substance; this term includes, but is not limited to, organic
materials used as dissolvers, viscosity reducers, degreasing
agents, or cleaning agents. Any excluded VOC is not a solvent.
(24) Substrate. The surface onto which a coating
is applied or into which a coating is impregnated.
(25) Surface coating. A material applied onto or
impregnated into a substrate for protective, decorative, or
functional purposes. Such materials include, but are not limited
to, paints, varnishes, primers, sealants, adhesives, inks and
maskants.
(26) Wash coat. A coating which contains binders
that raise wood surfaces, prevent undesired staining, and control
penetration.
223.3 Volatile organic compound emission control
requirements.
(a) No person shall cause or allow the usage of
coatings that exceed the allowable pounds of volatile organic
compounds per gallon, minus water and excluded VOC at application
specified in table 1 of section 228.7 and table 2 of section
228.8 of this Part, unless a coating system meeting the
requirements of 228.3(d) is utilized or unless control equipment
meeting the requirements of 228.3(b) and 228.3(c) is installed
and operated.
(b) Any afterburner used as control equipment
shall be energy-efficient and shall be designed and operated to
provide, at a minimum, for an 80 percent overall removal
efficiency of volatile organic compounds. This assumes 90 percent
of the volatile organic compounds emitted are captured and
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delivered to the afterburner which converts 90 percent of the
volatile organic compounds to carbon dioxide and water vapor. The
control equipment shall operate on minimal auxiliary fuel and
provide for maximum heat recovery.
(c) Notwithstanding the control requirements
specified in 228.3(b), control strategies utilizing an air
cleaning device must determine the required overall removal
efficiency on a solids as applied basis as per 228.2(b)(22).
Using the appropriate coating parameters and VOC limits as
specified in sections 228.7 and 228.8, the overall removal
efficiency required is the lesser of the value calculated
according to the above procedure or 85 percent.
(d) An owner or operator of a coating line which
utilizes a coating system as a control strategy must comply with
the following provisions:
(1) Each coating system must be approved by the
commissioner's representative prior to the use of the coating
system in the manufacture of a product for sale;
(2) The coatings must be applied on the same
substrate and at the same coating line. Coating applied at
different coating lines cannot be included in any compliance
demonstration involving a coating system. In addition, due to
the variability in coating application rates, coatings which are
applied manually by hand held spray guns cannot be utilized in a
coating system compliance demonstration.
(3) Compliance must be demonstrated using actual
coating usages calculated on a solids as applied basis using the
formula in 228.2(b)(22). The calculation must be performed for
each coating and the aggregate of the results for all coatings
applied in each coating system must demonstrate compliance;
(4) Compliance must be demonstrated
instantaneously. There is no averaging period for individual
coatings which are part of a coating system;
(5) The method or instrument which the source
owner will accurately measure or calculate the volume of coating
applied must be approved by the commissioner's representative;
(6) Collect and record all of the following
information:
(i) the name or identification of each coating
which is part of a coating system;
(ii) the coating parameters used to determine
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(VOC)a for each coating which is part of a coating system; and
(7) Any record showing noncompliance with this
Part shall be reported by sending a copy of the record to the
commissioner's representative within thirty days following the
occurrence.
(e)(l)The commissioner may allow surface coating
processes to operate with a lesser degree of control than is
required by 228.3 provided that a process specific reasonably
available control technology (RACT) demonstration has been made
to the satisfaction of the commissioner.•» Process specific RACT
demonstrations shall be submitted with the application for a
permit to construct, a certificate to operate, or renewal of a
certificate to operate for an existing source under the
provisions of Part 201 of this Subchapter. Such process specific
RACT demonstrations must be submitted to the United States
Environmental Protection Agency as a revision to the State
Implementation Plan and must address the technical and economic
feasibility of:
(i) utilizing compliant coating(s) and/or inks;
(ii) utilizing demonstrated and proven emission control
technologies which would achieve the required overall removal
efficiency as determined per 228.3 (c);
(iii) utilizing demonstrated and proven emission
control technologies which would achieve a degree of overall
removal efficiency less than required as determined per 228.3(c);
and
(iv) utilizing demonstrated and proven production
modification methods which would result in real, documented, and
enforceable reductions in the volatile organic compound emissions
from the process.
(2) Facilities with surface coating processes subject to
this Part with an annual potential to emit of less than 5 tons of
volatile organic compounds will only be required to comply with
(d)(1)(i) and (d)(1)(iv) in order to demonstrate that a lesser
degree of control is RACT for these processes.
(3) The commissioner may allow sources which use natural gas
fired afterburners as control devices for processes subject to
this Part, to shut down these natural gas fired afterburners from
November 1st through March 31st for the purposes of natural gas
conservation, provided that the commissioner has determined that
this action will not jeopardize air quality. Such evidence shall
be submitted with the application for a permit to construct, a
certificate, or renewal of a certificate to operate for an
existing source under the provisions of Part 201 of this
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Subchapter.
228.4 Opacity. No person shall cause or allow
emissions to the outdoor atmosphere having an opacity of 20
percent or greater for any consecutive six-minute period from any
emission source subject to this Part.
228.5 Reports, recordkeeping, sampling and
analysis.
(a) The owner or operator of any emission source
subject to this Part must maintain and, upon request, provide the
Department's representative with certification from the coating
supplier/manufacturer which verifies the parameters used to
determine the actual VOC content of the as applied coating,
(VOC)a, as defined in section 228.2(b)(ll) of this Part, for each
coating used at the facility. In addition, purchase, usage
and/or production records of the coating material, including
solvents, must be maintained in a format acceptable to the
commissioner's representative and, upon request, these records
must be submitted to the Department. Any facility required to
perform solids as applied calculations as defined in section
228.2(b)(22), must maintain records to verify the parameters used
in the formula. Any additional information required to determine
compliance with this Part shall be provided to the commissioner's
representative in a format acceptable to the representative.
Records must be maintained at the facility for a period of five
years.
(b) Acceptable analytical methods for determining
the volatile content, water content, density, volume solids of
surface coatings are presented in appendix A, method 24, of 40
CFR 60 (see table 1, section 200.9 of this Title).
(c) Where the methods referenced in subdivision
(b) of this section are not applicable, alternate analytical
methods for surface coating may be acceptable, subject to the
approval of the commissioner.
(d) Representatives of the Department of
Environmental Conservation shall be permitted, during reasonable
business hours, to obtain coating samples for the purpose of
determining compliance with this Part.
(e) When a coating line utilizes control
equipment to comply with the provisions of this Part, test
methods acceptable to the Department of Environmental
Conservation must be used when demonstrating the overall removal
efficiency.
(i) This demonstration may be performed by directly
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measuring VOC/solvent recovery and VOC/solvent usage rates where
VOC/solvent recovery is the only control technique. Methods
described in 228.5(b) and (c) must be used.
(ii) For control equipment other than VOC/solvent
recovery, this demonstration must include provisions to determine
both the efficiency of the capture system and of the subsequent
destruction and/or removal of these air contaminants by the
control equipment prior to their release to the atmosphere.
(f) The owner and/or operator of a surface coating
process must follow notification requirements, protocol
requirements and test procedures of Part 202 of this Title for
testing and monitoring. Depending upon conditions at a test site,
one of the following test methods from appendix A of 40 CFR 60
(see Table 1, section 200.9 of this Title) must be used when
measuring volatile organic compound (VOC) concentrations of a gas
stream at the inlet and outlet of a control device to determine
the destruction and/or removal efficiency:
(i) Method 18, Measurement of Gaseous Organic Compound
Emissions by Gas Chromatography;
(ii) Method 25, Determination of Total Gaseous Organic
Emissions as Carbon; or
(iii) Method 25A, Determination of Total Gaseous
Organic Concentration Using a Flame lonization Analyzer.
(iv) Methods not listed above must be approved in
advance by the Department's representative and the United States
Environmental Protection Agency.
(g) If an air cleaning device is used, continuous
monitors of the following parameters shall be installed,
periodically calibrated, and operated at all times that the
associated control equipment is operating:
(1) exhaust gas temperature of all
incinerators;
(2) temperature rise across catalytic
incinerator bed;
(3) breakthrough of volatile organic
compounds on a carbon adsorption unit; and
(4) any other continuous monitoring or
recording device required by the commissioner.
(h) Any facility which is not subject to the
control requirements of this Part because its annual potential to
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emit volatile organic compounds are below the applicability
criteria, must maintain records in a format acceptable to the
commissioner's representative that verify the facility's annual
potential to emit VOCs. Upon request, these records must be
submitted to the Department.
228.6 Prohibition of sale or specification.
(a) No person shall sell, specify, or require
for use the application of a coating on a part or product at a
facility with a coating line described in table 1 or 2 in section
228.8 or 228.9 if such use is prohibited by any of the provisions
of this Part. The prohibition shall apply to all written or- oral
contracts under the terms of which any coating is to be applied
to any part or product at an affected facility. This prohibition
shall not apply to the following:
(1) coatings utilized at surface coating lines
where control equipment has been installed to meet the allowable
VOC content limitations specified in tables 1 and 2 of
sections 228.8 and 228.9 of this Part;
(2) coatings utilized at surface coating lines
where a coating system is used which meets the requirements
specified in 228.3(d); and
(3) coatings utilized at surface coating lines
that have been granted variances for reasons of technological and
economic feasibility per section 228.3(e) of this Part.
(b) Any person selling a coating for use in a
coating line subject to this part must, upon request, provide the
user with certification of the volatile organic compound content
of the coating supplied.
228.7 Table 1
Process, emission source, Maximum permitted
and description of products pounds of volatile organic
compounds per gallon (minus
water and excluded VOC)
of coating at application
Large appliance Residential and commercial washers,
coating lines refrigerators, freezers, water heaters,
dishwashers, trash compactors, air
conditioners. 2.8
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Magnet wire insu-
lation coating
lines
Enameling or varnish of aluminum or
copper wire for use in electrical
machinery to create an electromagnetic
field.
1.7
Metal furniture
coating lines
Metal parts used in household, business
and institutional furniture such as but
not limited to tables, chairs, waste-
baskets, beds, lighting fixtures,
shelves, room dividers, bathropm
dividers. 3.0
Metal can
coating lines
Fabric coating
lines
Vinyl coating
lines
Paper coating
lines
Automobile
assembly coating
lines
Sheet basecoat - exterior and interior
over-varnish 2.8
Two-piece can exterior (basecoat and
over-varnish) 2.8
Two- and three-piece can interior
body spray 4 .2
Two-piece can exterior end (spray or
roll coat) 4.2
Three-piece can side-seam spray 5.5
End sealing compound 3.7
Fabric coatings, such as but not limited
to: rubber, used for rainwear, tents,
industrial gaskets. 2.9
Printing, decorations or protecting coats
over vinyl-coated fabric or vinyl
sheets. 3.8
Paper, pressure-sensitive tape regardless
of substance (including paper, fabric or
plastic film) and related web coating
processes on plastic film such as but not
limited to: typewriter ribbons, photo-
graphic film and magnetic tape. Also
metal foil gift wrap and packaging. 2.9
Automobiles and light-duty trucks,
exterior and main body sheet metal parts
excluding nonmetallic parts.
Prime coat
Primer-surfacer
Top coats
Repair coat
1.9
2.8
2.8
4.8
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Coil coating
lines
Flat metal sheet from a coil or roll
which is coated and later used for items
such as but not limited to: cans,
appliances, roof decks, siding, cars,
gutters. 2.6
Coating lines for
misc. metal parts
arid products
Large farm machinery, small farm and
garden machinery, small appliances,
commercial and office machinery,
computer equipment, industrial machinery,
fabricated metal products and any other
industrial category which coats
miscellaneous metal machinery/ instruments
or equipment, excluding all nonmetallic
parts.
Clear coatings 4.3
Coating application system is air
dried or forced warm air dried at
temperature up to 90°C 3.5
Extreme performance coatings
designed for harsh exposure or
extreme environmental conditions 3 .5
All other misc. metal parts and
products coatings 3 .0
Coating lines for
flat wood surface
finishing
Printed interior panels made of
hardwood, plywood and thin particle
board 2.5
Natural finish hardwood plywood panels 3.3
Hardboard paneling 3 .6
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228.8 Table 2
Process, emission source,
and description of products
Woo.d coating lines
Maximum permitted
pounds of volatile organic
compounds per gallon (minus
water and excluded VOC)
of coating at application
Coated room furnishings, such as but
not limited to cabinets (kitchen, bath
and vanity), tables, chairs, beds, sofas,
shutters, art objects and any other
coated product made of solid wood
composition or wood material.
Semi transparent stain 6.8
Wash coat 6.1
Opaque stain 4.7
Sealer 5.6
Pigmented coat 5.0
Clear topcoat 5.6
Tablet coating
lines
Formed pharmaceutical products, such as
but not limited to pills, capsules.
5.5
Glass coating
lines
Leather coating
lines
Miscellaneous
plastic part
coating lines
Lamps, incandescent light bulbs and
miscellaneous glass products.
Fluorescent light bulbs.
Leather substrates, such as but not
limited to clothing, furniture,
automobile components.
3.0
4.1
5.8
Plastic parts and products such as but not
limited to business and office machine parts
toys, sporting goods, architectural
structures such as doors and window frames,
automotive interior parts; automotive
exterior parts, both flexible and rigid;
musical equipment housings; and other
miscellaneous plastic parts.
Color topcoat
Clear coat
3.8
4.8
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Aerospace Aerospace components, including but not
coating lines limited to assembly of parts or completed
unit of any aircraft, helicopter or
missile.
Primer 2.9
Topcoat 5.1
Maskant for chemical processing 5.1
Motor vehicle Automobile, truck or bus coating,
refinishing including but not limited to repair
coats, repainting and touch-ups, except
at automobile assembly plants.
Repair/touchups 6.2
Overall (coating entire vehicle) 5.0
Urethane coating Urethane substrates that are more than
lines 50 micrometers (0.002 inches) thick,
except for resilient floor covering and
flexible packaging. 3.8
228.9 Products regulated. The "Process, emission
source, and description of products" column in tables 1 and 2 of
sections 228.7 and 228.8 of this Part may not contain all
possible products in each category. For any products not
specifically listed, the commissioner will determine, based on
inspections of the process, emission source and product to be
coated, which limits in table 1 or 2 apply.
228.10 Handling, storage and disposal of volatile
organic compounds(VOC). No owner or operator of a facility
subject to this Part shall:
(a) Use open containers to store or dispose of
cloth or paper impregnated with VOC and/or solvents that are used
for surface preparation, cleanup or coating removal;
(b) Store in open containers spent or fresh VOC
and/or solvents to be used for surface preparation, cleanup or
coating removal;
(c) After January 1, 1994 use VOC and/or solvents
to cleanup spray equipment unless equipment is used to collect
the cleaning compounds and to minimize their evaporation to the
atmosphere;
(d) Use open containers to store or dispense
surface coatings and/or inks unless production, sampling,
maintenance or inspection procedures require operational access.
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This provision does not apply to the actual device or equipment
designed for the purpose of applying a coating material to a
substrate. These devices may include, but are not limited to
spray guns, flow coaters, dip tanks, rollers, knife coaters, and
extrusion coaters; or
(e) Use open containers to store or dispose of
spent surface coatings, spent VOCs and/or solvents.
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State of Wisconsin
C-37
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NR 422.085 Leather coating. (1) APPLICABILITY. Effective February 1,
1987, this section applies to coating applications at leather coating facili-
ties. This section does not apply to sources exempted under s. NR 422.03
(6).
(2) EMISSION LIMITATIONS. No owner or operator of a leather coating
facility may cause, allow, or permit the emission of any VOGs from coat-
ing applications in excess of 18.6 kilograms per 100 square meters (38.0
pounds per 1000 square feet) of coated product calculated on a daily av-
erage basis.
Register. May, 1992. No. 437
(3) COMPLIANCE REQUIREMENTS AND SCHEDULES. The owner or opera-
tor of a leather coating facility shall comply with the requirements of
sub. (4) and s. NR 425.03 (1), (8) and (9).
(4) REPORTING AND RECORDKEEPING. (a) To determine compliance
with the leather coating VOC emission limit in this section, the facility
shall maintain daily coating usage and leather production records in a
format approved by the department. Reporting, recordkeeping and ac-
cess to these records shall be in accordance with ss. NR 439.03 to 439.05.
(b) The daily VOC emission rate shall be determined by the following
equation:
c - a/b
where:
c is the daily average VOC emission rate,
a is the total amount of VOCs emitted during the day, and
b is the prorated surface area of leather coated during the day, where:
di is the'total area of the ith batch of hides coated during the day, and
6j is the ratio of actual VOC emissions resulting from coating any por-
tion of the ith batch of hides during the day to the total predicted VOC
emissions resulting from all coating of the entire ith batch.
(c) The facility shall measure the surface area of each piece of leather
coated with a mechanism initially calibrated for minimum accuracy to
the Turner Korrect Machine or Sawyer Measurement systems. The av-
erage surface area per coated piece of leather may be used for a batch of
leather provided that the average is based on a minimum of 500 pieces.
Otherwise, the facility average surface area per coated leather piece shall
be used. In no case may the total area allocated to production over all
days from a piece of leather exceed the average area for that leather.
History: Cr. Register, January, 1987, No. 373. eff. 2-1-87; am. (2) and (3), er. (4). Register.
February, 1990. No. 410. eff. 3-1-90.
NR 422.09 Automobile and light-duty truck manufacturing. ( 1 ) APPLICA-
BILITY. This section applies, subject to the provisions of s. NR 425.03
(6), to the application areas, flashoff areas, and ovens of automobile and
light-duty truck manufacturing plants involved in prime, topcoat and
final repair coating of metallic front end and main body parts. This sec-
tion does not apply to the coating of wheels, trunk interiors, steering
columns or nonmetallic parts; to sealers or nonpriming anti-rust coat-
ings; or to sources exempted under s. NR 422.03.
(2) EMISSION LIMITATIONS — ENAMELS. No owner or operator of an
automobile surface coating line which, prior to January 1, 1979, used an
enamel coating system, may cause, allow or permit the emission of any
VOCs in excess of:
(a) After December 31, 1983, 0.14 kilograms per liter of coating (1.2
pounds per gallon), excluding water, from an electrodeposition prime
coat or equivalent coating line.
Register. May. 1992. No 437
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C-40
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Technical Support Oocumeat
For The
Proposed Wisconsin Administrative Code Rule To Limit
Volatile Organic Compound Emissions
From Major Leather Coating Facilities
In the Southeastern Wisconsin
Ozone Nonattainment Area
Wi
sconsin Department of Natural Resources
Bureau of Air Management
P.O. Box 7921
Madison, Wisconsin 53707"
August, 1986
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Preface
This draft document details the Wisconsin Department of Natural Resources
CWONR) Bureau of Air Management's efforts to research and develop a proposed
administrative rule that would establish volatile organic compound (VOC)
emission limitations for large leather coating facilities. Large leather
coating facilities are defined as emitting at least 100 tont of VOC's during a
calendar year.
VOC emissions are a precursor to ambient ozone formation. The accepted
general strategy to reducing ambient ozone is to lower VOC emissions.
This proposed rule would apply to approximately three major stationary sources
in the southeastern Wisconsin ozone nonattainment area.
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TABLE OF CONTENTS
Title Page
Preface i
Table of Contents iii
List of Tables iv
List of Figures iv
BODY OF REPORT
1. Introduction
1.1 Document Purpose 1
1.2 Ozone: Cause and Effects 1
1.3 Regulatory Background 2
1.4 Document Outline 5
2. RACT IV Source Investigation 7
2.1 InitialPotential RACT IV Listing 7
2.2 Revised Potential VOC RACT Facilities Listing 7
2,3 RACT IV Criteria and Data Sources 8
3. Leather coating - VOC RACT Assessment 9
3.1 Leather coating in Southeast Wisconsin 9
3. 2 Process Description 9
3.2.1. The Tanning Process 9
3.2.2. Leather Finishing Methods 10
3.2.3. Coating Formulations n
3 . 3 VOC Emission Rates 14
3.4 Potential Leather coating VOC RACT Measures and Cost 16
3.4.1. Low Organic Solvent Coatings 16
3.4.2. Roll Coating 16
3'.4.3 Microprocessor Controls on Air-Atomized
Spray Equipment 18
3.4.4. Add-on Controls. 20
3.5 Proposed Leather Coating VOC RACT Emission
Limitations Rule 21
3.5.1. Proposed VOC Emission Limits 21
3.5.2. Proposed Rule Flexibility in Meeting the VOC
Emission Limits 24
3.5.3. Recordkeeping and Reporting Requirements 25
3.5.4. Proposed Compliance Schedule and Variance
Provisions 25
3.5.5. Estimated Impact of the Proposed Rule .' 26
References '. . . 21
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LIST OF TABLES
Table Paj
1 VOC RACT Source Categories - Southeastern Wisconsin 4
2 Representative Leather Coating Formulations and Cost 15
3 VOC Emission Rates - Various Leather 17
4 Estimated Annualized Cost per Ton of VOC Reductions -
Industrial Surface Coating Categories in Wisconsin
that are Subject to RACT 19
5 Estimated Annuaiized Cost - Thermal Incineration
No Heat Recovery) 22
LIST OF FIGURES
Figure Description
1 Southeastern Wisconsin Ozone Nonattainment Area 6
2 Spray Coating - Schematic Picture 11
3 Roll Coating Operations - Schematic Diagram 11
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Chapter One
Introduction
1.1 Document Purpose
This document details the Wisconsin Department of Natural Resources
("Department") Bureau of A1r Management's efforts to research and develop a
proposed administrative rule that would establish volatile organic compound
(VOC) emission limitations for certain leather coating operations. This rule
for leather coating operations Is the last In a series, of four rules to limit
VOC emissions from certain sources In southeastern Wisconsin.
VOC emissions are precursors to ambient ozone formation. The accepted
strategy to reducing ambient ozone concentrations Is to reduce VOC emissions.
The criteria that all these sources would have to meet for rule applicability
are as follows:
Sources that emitted 100 tons or more of VOCs during calendar year 1984
(or the most recent year for which emissions data are available);
Sources that are located in the southeastern Wisconsin ozone nonattainment
area (I.e., within the counties of Kenosha, Ozaukee, Racine, Milwaukee,
Washington or Waukesha);
Processes that are -not subject to any existing DNR Reasonably Available
Control Technology (RACT) VOC emission limitations; and
Processes that are not the subject of any Control Technique Guideline
(CTG) issued by the U.S. Environmental Protection Agency (U.S. EPA), which
recommends Reasonably Available Control Techniques (RACT).
Following these criteria, the WDNR developed, proposed, and eventually
promulgated non-CTG or "RACT IV" rules to limit VOC emission from the
following applicable sources:
Synthetic resin manufacturing
Coatings manufacturing, and
Aerosol can fi11 ing
At its February 1986 meeting, the Natural Resources Board adopted these rules
as part of the administrative code. The rules are scheduled to take effect on
September 1, 1986.
The remainder of this document addresses the technical background and basis
for the proposed VOC RACT IV rule for leather coating facilities.
0-45
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1.2 Ozone: Cause and Effects
• Ozone (Oi) is formed in the lower atmosphere in the presence of nitrogen
dioxide and sunlight. Ultraviolet radiation from the sun provides the
necessary energy level to disassociate nitrogen dioxide (NO,) into nitric
• oxide (NO) and a free oxygen atom which quickly combines with an oxygen
molecule to form ozone. Ozone may then disassociate to form H0t and this
photochemical process continues to repeat, always attempting to reach
equl1Ibrlum.
However, If the atmosphere is polluted with VOC emissions as well as NO;.
the equilibrium shifts towards greater concentrations of ozone. Although some
organic compounds.react much more rapidly than others, almost all will react
with NO and both ordinary oxygen and ozone. In a series of reactions, oxygen
as well as ozone react with NO to form N02. Organic compounds and oxygen
are replaced In the reaction with NO, causing ozone concentrations to
bu1ld-up. Thus, the simultaneous presence of both nitrogen-dioxide and VOC in
the presence of sufficient solar radiation causes ozone to accumulate.
Since VOCs and N02 react In the presence of sunlight to form ozone, they are
called precursors of ozone. VOC's can also unite directly with ozone to form
other photochemical oxldants which are often as harmful as ozone Itself.
The toxlcity of Inhaled ozone is well known, and the presence of this oxidant
In most urban and Industrial environments has made the study of its health
effects important.
At ozone concentrations greater than 0.25 parts per million (ppm), irritation,
headaches, decreased cardiopulmonary reserve (in healthy adults), aggravation
of certain anemias, aggravation of chronic lung disease, aggravation of
asthma, and Increased susceptibility to acute respiratory disease have been
noted.
At ozone concentrations from 0.20 ppm to 0.25 ppm, Brinkman, Kleinfield,
Remmers and Schoettlen (1957) found that aggravation of certain respiratory
aiIments occurred.
At ozone levels below 0.20 ppm, Wayne, Hammer, and Coffin (1967) discovered
mild reactions in normal subjects, ranging from headaches without fever at
0.05 ppm to eye irritations at 0.10-0.15 ppm.
A 1982 study by the United States Congress's Office of Technology Assessment
(OTA) estimates that ozone-induced damage is costing the nation between S2
billion and $4.5 billion per year in reduced yields for four major crops
(corn, wheat, soybeans, peanuts). These estimated losses represent as much as
five per cent of the nation's output.
Ozone is also a major factor in the overall deterioration of several different
types of organic materials. The magnitude of damage is difficult to assess
because ozone is one of many oxidizing chemicals which contribute to the
"weathering" of materials. Nevertheless, ozone is known to accelerate the
deterioration of rubber, textile dyes and fibers, and certain types of paints
and coatings.
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1.3 Regulatory Background
The U.S. EPA, based upon the most reliable data available, has established a
National Ambient Afr Quality Standard (NAAQS) for ozone to protect human
health (primary standard) and welfare (secondary standard). For ozone the
primary and secondary NAAQS are the same: 0.12 parts per million (ppm) -
daily maximum 1-hour concentration. The ozone standards are attained when the
expected number of days per calendar year with maximum hourly average
concentrations above the designated level is equal to or less than one, as
determined by the methodology of Chapter 40 of the Code of Federal
Regulations. Appendix H (40 CFR 50.9. Appendix H) The WONR has adopted this
ozone NAAQS as part of Wisconsin Administrative C,ode section NR 155.03.
Areas where violations of any of the NAAQS exist are considered by the U.S.
EPA and the affected state to be in-nonattainment for that criteria pollutant
for which the NAAQS exists. Officially, these nonattainment areas are deemed
to contain ambient air quality that is less than what Is considered safe for
human health and/or welfare.
Section 110(a) of the Federal Clean Air Act. amended August, 1977 required
each state to submit a revised air quality state Implementation plan to the
U.S. EPA by July 1, 1979 that demonstrates attainment of the NAAQS by
December 31, 1982 for each pollutant that did not meet the NAAQS in any part
of the state (i.e., the nonattainment areas). The WONR Bureau of Air
Management submitted a 1979 Plan for ozone attainment to the U.S. EPA for
approval.
The two general strategies to reduce ozon-e, as proposed in the 1979 Ozone
Plan, were to limit VOC emissions from new cars (The Federal Motor Vehicle
Emission Control Program - FMVECP), and from certain stationary sources. The
remainder of this report will be concerned with the VOC emissions and their
limitations from stationary sources.
The stationary source VOC emission limitations (called VOC Reasonably
Available Control Technology - RACT) that are described in the 1979 Ozone Plan
were developed by the WDNR Bureau of Air Management and are contained as rules
in section NR 154.13 of the Wisconsin Administrative Code. In September,
1986, these rules will be renumbered into the NR 400 series. These VOC RACT
rules were adopted from U.S. EPA control technique guidelines (CTG's). The
CTG's and subsequent RACT rules were issued in Group I and Group II series.
Table 1 lists those VOC stationary source RACT I and RACT II categories that
are currently applied in the southeastern Wisconsin ozone nonattainment area
The 1979 Ozone Plan's general strategy to attain the ozone NAAQS was and still
is to reduce VOC emissions. Based upon the analysis of the impacts of
specific VOC-reducing strategies, the WONR determined that the ozone NAAQS
would not be met by December 31, 1982 for southeastern Wisconsin.
Section 129(c) (uncodified) of the Clean Air Act allowed the U.S. EPA to grant
extensions for achieving ozone NAAQS attainment to Oecemb-er 31, 1987 to tnose
states which could not demonstrate attainment by the end of 1982. As a
condition of U.S EPA's approving this extension, each state that applied for
the extension (e.g., Wisconsin) was required to develop a motor vehicle
emissions inspection and maintenance (I/M) program and additional stationary
source VOC RACT rules for the ozone nonattainment areas (Section 172(a>(2> of
the Clean Air Act).
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Table 1
Implementation and Anticipated Ful1-Compliance Dates
Stationary Source Categories Subject to .423(a) VOC Rules
Contained In Chapters NR 419
Southeastern Hisconsln Seven Counties '"'
Source Category
Effective Date
of Implementing
the Regulation
Anticipated Date of
Full Source Category
Compllance
Bulk Gasoline Plants
Gasoline Loading Terminals
Service Stations (Stage I)
Industrial Coating Categories
Appl lances
Automobi les
Cans
Metal Colls
Paper
Fabrics
Metal Furniture
Misc. Metals
Solvent Metal Cleaning
Cutback Asphalt Oper.
Rubber Products
Drycleanlng
Graphic Arts
Petroleum-based Dry Cleaning
Synthetic Resin Manufacturing'
Coatings Manufacturing6
Aerosol Can Filling6
August 1, 1979
August 1, 1979
August 1, 1979
August 1. 1979
August 1, 1979
August 1, 1979
August 1 , 1979
August 1, 1979
August 1, 1979
August 1, 1979
April 1, 1981
August 1, 1979
August 1 , 1979
April 1, 1981
April 1, 1981
April 1, 1981
January 1 , 1984
September 1 , 1986
September 1 . 1986
September 1 , 1986
December 31 ,
December 31 ,
December 31 ,
December 31 ,
December 31 ,
December 31 ,
December 31 .
December 31 ,
December 31 ,
December 31 ,
December 31 ,
December 31 ,
December 31 .
December 31 ,
December 31 ,
December 31 ,
December 31 ,
December 31 ,
December 31 ,
December 31 ,
1981
1981
1981
1981
1987
1985
1982
1985
1979
1982
1987
1981
1980
198-3
1983
1985
1987
1987
1987
1987
Transferred from the old NR 154.13, effective October 1, 1986.
This list of stationary source categories subject to VOC emission
control regulations are for only those categories that have sources
In the Southeastern Wisconsin seven counties. Additional source
types subject to NR 154.13 regulations but presently not located in
Southeastern Wisconsin are: Storage of petroleum liquids,
miscellaneous refinery sources, petroleum refinery fugitive
emissions, pharmaceutical manufacturing, gasoline tank truck leaks.
RACT IV source category.
7634Q.PERM
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In March, 1983 the Department submitted to the U.S. EPA the final revision to
the 1982 State Air Quality Management Implementation-Plan, for ozone control
in the six county southeastern Wisconsin ozone nonattalnment region
(Figure 1>. This document, referred to herein as 1982 Ozone Plan, contains
predictions of the Impact that federal and Wisconsin VOC emission limitation
rules would have on high ozone levels In the region in 1987 (projected
attainment year) relative to concentrations In 1979-81. 1980 was the base
year for this analysis.
As part of the 1982 Ozone Plan, the Department committed to developing an I/M
program In the southeastern Wisconsin ozone nonattalnment Area, per U.S. EPA
requirements. This program commenced operation ,on April 2, 1984.
The Department, 1n Its 1982 Ozone Plan, also committed to developing
additional VOC RACT rules for any applicable- stationary processes, per the
federal requirements. This commitment included the adoption of the CTG -
Group III VOC emission limitations ("RACT III") for applicable operations
located in southeastern Wisconsin. The DNR has complied with this commitment
by promulgating a RACT III rule for petroleum-based dry cleaning operations in
the region with annual VOC emissions greater than 100 tons per year (TPY).
Additional RACT III enactment will occur if and when there are applicable
facilities in southeastern Wisconsin.
The U.S. EPA, in the January 22. 1981 Federal Register (46 FR Page 7186). also
stated that the additional requirements to be a part of the 1982 Ozone Plan
are to Include the adoption of rules "applying RACT to ... all remaining
[non-CTG] major stationary sources of VOC's" [i.e., emitting more than 100
tons per year actual emissions as defined under Section 302(j) of the Clean
Air Act]. These sources are referred to as non-CTG or RACT IV VOC sources.
The Department is in the process of meeting this requirement, as discussed
herein.
1.4 Document Outline
In this document, the Department details its analysis of three potential
leather coating RACT IV sources in southeastern Wisconsin, and how the
criteria for probable RACT IV sources were established (Chapter Two).
Technical support for promulgating the proposed leather coating VOC RACT IV
rule is detailed in Chapter Three.
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Figure 1
Southeastern Wisconsin
Czone Nonattainment Court
• WASHINGTON p
•
!
/
• Grafton
Slinger
V%AU«. £Sn-.
• i
Waukesha
I .V,lwauk«
\
' 7 /
V 7
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Chapter Two
RACT IV Source Investigation
2.1 Initial Potential RACT IV Listing
This phase of the project commenced by defining a potential RACT IV source, in
terms of both total emissions and geographical location. Potential RACT IV
processes were defined to have had the potential to emit at least 100 tons of
VOCs for calendar year 1983, assuming continuous, maximum operations for the
entire year. The Department's 1983 Air Emissions Inventory (AEI) was the
primary source for this data survey.
Since only the ozone plan for the southeastern Wisconsin ozone nonattainment
area had to be revised, it was deemed that any additional VOC control rules
would apply only to appropriate sources that are located in this region (i.e.,
the counties of Kenosha, Milwaukee, Ozaukee, Racine, Washington, and Waukesha,
Figure 1). This geographical limitation Identically applies to any RACT III
VOC limitation and the I/M program, which were also commitments from the 1982
Ozone Plan.
In reviewing the 1983 AEI, the Department identified twelve facilities that
met the above-mentioned criteria. For each of these facilities, a plant
inspection and a developed detailed 1983 VOC emissions inventory. The
facility inspections were carried out during April - June, 1984. Each of
these plant visits had the following purposes:
To enable the DNR to better understand those processes that result in the
VOC emissions;
To explain the purpose and background for this rule development; and
To solicit operations Information and detailed VOC emission estimates
regarding each of the processes in question. Confidentiality privileges
under Wisconsin Statute and Wisconsin Administrative Code were offered by
the DNR.
Based upon data supplied by the facilities and their coatings/solvents
vendors, the Department was able to develop a detailed 1983 VOC emissions
inventory for each facility. Each inventory was finalized and considered
complete. Appropriate facility personnel approved, in writing, the DNR
Inventorying method and calculations. The reported VOC emissions from
calendar year 1984 operations are now used in this RACT analysis.
2.2 Revised Potential VOC RACT IV Facilities List
In December, 1983 the Department promulgated the RACT III rule that limited
VOC emissions from major petroleum-based drycleaning operations in
southeastern Wisconsin. "Major" operations were defined as any facility
process (or group of processes if similar but more than one) emitting 100 tons
or more VOCs per calendar year. The Department decided to propose that the
diminimus VOC emission value, below which a source would be exempt from
further RACT IV consideration, would also be 100 ac-tual tons per calendar
year. This diminimus value would conform to the U.S. EPA guidance on RACT [[I
rule promulgation (46FR7136. see Section 1.3 herein).
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Based upon the Inventorying effort, geographical restriction, and the 100
ton-per-year actual VOC emissions minimum for potential RACT IV sources, the
list of facilities that may be subject to an.RACT emission limitations was
culled to seven (four leather coater's, a resin manufacturer, a coatings
manufacturer, and an aerosol can filling operation). The primary step in this
rule-development process is a RACT assessment and feasibility analysis for
each of the process types listed above.
During October - mid-December, 1985, the Department solicited public comment
on all draft VOC RACT IV rules. This included a public hearing on
November 15, 1985 In Milwaukee.
Based upon the comments received, the Department decided to separate the VOC
RACT IV rules package. The revised rules for synthetic resin manufacturing,
coatings manufacturing and aerosol can filling-operations were eventually
adopted by the Natural Resources Board, at Its February, 1986 meeting. Thess
three rules are scheduled to become effective as part of the Wisconsin
Administrative Code on September 1, 1986.
.Further Department work on the remaining draft VOC RACT IV rule (leather
coating) was delayed until after the other RACT IV rules were adopted by the
Natural Resources Board. The comments received on both proposed rule and its
supporting materials were considerably more substantial than for the other
rules. This technical support document focuses solely upon background and
basis for the proposed leather coating VOC RACT rule.
2.3 RACT IV.Criteria and Data Sources
The U.S. EPA has defined RACT as follows:
"The lowest emission limitation that a particular source Is capable of meeting
by the application of control technology that is reasonably available
considering technological and economic feasibility. RACT for a particular
source is determined on a case-by-case basis, considering the technological
and economic circumstances of the Individual source." (Federal Register,
September 17, 1979, Page 53762). This definition was a primary criteria, in
the entire RACT IV rule development process.
In working towards understanding the leather coating process as a VOC source,
the Department has used the following sources of Information:
Existing CTG's and Wisconsin VOC RACT rules - noting where similarities
may exist between CTG and the non-CTG processes;
Facility Information and recommendations, primarily during the fall, 1985
public comment period;
Information from other states which have leather coating VOC RACT rules;
and
The Department's understanding of this process In assessing what might
constitute RACT for it.
Chapter Three contains the Department's understanding of the leather coating
process, Its role as a VOC emission source and how these emissions could: be
reduced through reasonably available control technology (RACT).
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Chapter Three
Leather Coating
VOC RACT Assessment
3.1
Leather Coating in Southeast Wisconsin
Leather coating is a principle process In the animal hide tanning industry
which stabilizes and transforms animal hides Into a diverse variety of lea
types. This Industry is quite significant In southeastern Wisconsin.
,
eather
Leather coating Is a large source of VOC emissions.
coating facilities In the region which each emitted
during 1984. These four facilities reported to the
Inventory a total of 1054 tons of VOC emissions for
are 1isted as follows:
There were four leather
at least 100 tons of VOC's
ONR Air Emissions
calendar year 1984, and
1) Amity Leather Products Company
West Bend
DNR Facility Identification Number (FID#) 267009710
2) Flagg Tanning Corporation
Ml Iwaukee
FID #241030020
3) Gebhardt - Vogel Tanning Company
Mi Iwaukee
FID #241038490
4) Pfister and Vogel Tanning Company
M1 Iwaukee
FID #241023750
3.2 Process Description
3.2.1 The Tanning Process
The raw hides that arrive at the leather coating facility (also called
tannery) must be readied before coatings can be applied to them. The
hides are trimmed, washed, and then removed of all remaining hair, fat,
muscle and other unwanted animal tissue by applying enzymes. A bating
(enzymes and salts) solution 1s applied to the hides to reduce swelling,
lower pH, and reopen the hide structure to allow removal of the degraded
proteins. After bating, hides are thoroughly washed to remove any
substances that have been loosed or dissolved.
The next major phase in hide processing is the actual tanning. Hides or
skins are tanned to give them the mechanical properties of leather, such
as abrasion resistance and flexibility, and to prevent them from
decaying. The main tanning agents used commercially are chromium
sulfate solutions.
Next, the hides are fed through a machine with two large rollers to
wring excess moisture from the material. Because hides are usually too
uses, the finer grade grain leather is often separated
side leather (called the split) after the initial tanning
operation using a machine resembling a horizontal
thick for most
from the flesh
bandsaw.
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Following the Initial tanning process, which Is primarily for
preservation of the fibers, operations are carried out to Impart the
desired look, feel, and working qualities specified by the customer.
Hides are placed In drums and first treated with retan formulations,
followed by dye formulations, and then by fat liquoring chemicals.
Finishing requires a series of operations which give leather its final
surface qualities. For this, chrome tanned hides are subjected to
several finishing processes, as follows:
- Setting out (smoothing and stretching),
- Drying,
- Water conditioning and buffing,
- Plating (smoothing and embossing), and
- Finishing
3.2.2 Leather Finishing Methods
The finishing materials are applied to leather by flow, rolling, or
spray equipment. Various coating materials, both water-based and
solvent-based, are used to provide abrasion and stain resistance, and to
enhance color and gloss. This stage of the tanning process results in
emissions of volatile organic compounds (VOCs) to the atmosphere.
A hide's first coating is often applied via the "flow" method. The flow
method 1s commonly used to soften and waterproof leather principally for
the shoe industry. Some of the VOC's in the coating may be permanently
bound in the leather. This is called impregnation. The conveyoMzed
hides are fed under a conduit for the flow coating. This conduit has a
line of holes at Its bottom. The coating flows through these holes in a
slow, steady stream or "curtain". The transfer efficiency of flow
coating is close to 1001. Sometimes this "impregnation" coat is applied
by roll coating, a method which will be discussed later.
Next, the hides are hand fed onto a conveyor belt that goes through a
varied combination of air atomized (Figure 2) and/or roll coating
machine (Figure 3) applications. The predominant type of leather
coating machine uses a rotary nozzle spray method, with either six or
eight spraying heads. For spray applications, the coating material is
fed Into the spraying system by vacuum hose from a 55 gallon drum. Only
one coating material is sprayed at each application.
The spraying arms are mounted on a central shaft and have the coating
fed to the spray guns via lines mounted on the arms. The arm rotates
and sprays the coating on the hide as it passes underneath it.
The front portion of the spray coater contains an optical or electrical
scanner that sizes up the continually-varying widths and gaps between
hides. This Information is used by a microprocessor to control the
release of coating through the spray nozzles so as to reduce the amount
of overspray. There is a water wash holding tank at'the bottom of the
open spray booth to catch any coating material that run off or miss the
hide. After the coating has been applied, the hide is allowed to dry,
either by passing through a dryer or by hang-drying before the nex: coat
i s applted.
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Figure 2
Single Spray Nozzle Operations
Schematic Picture
COATING
A. DIRECT ROLL COATER
APPLICATOR
COATING—i
DOCTOR BLADE
EVERSE ROLLER
PANEL
1. REVERSE ROLL CQATER
Figure 3
A. Direct Roll Coater
B. Reverse Rol1 Coater
Schematic Diagrams
C-55
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Another type of spray coating Is the oscillating arm. This system uses
the same conveying and drying system as the rotary sprayer. It differs
in that instead of having several guns mounted on a carousel, one gun i
mounted on an arm that swings back and forth. As with spray coater's,
microprocessors can be here used to reduce overspray.
The stationary sprayer is a line of spray nozzles that remain stationar
as the hides move underneath them. Again, microprocessors can be used
to reduce overspray from this equipment.
The sprinkler sprayer (or seasoner) Is used to sprinkle a coating onto
the hides at low pressure as they pass underneath. Microprocessors are
not commonly used here as the coating Is collected In a trough and
reused.
The use of the roll coater In leather coating is relatively new
technology that is based upon a combination of both pure roll coating
and the rotogravure process. The coating material Is applied to the
leather, In the opposite direction of the substrate movement by
revolving hard steel rolls (Figure 3). The depth of the coating is
determined by the gap between the rolls (A and 8 in Figure 3). This
process borrows from the rotogravure technique In that the coated roll
Is "pitted" with thousands of tiny recessed dots. The coating material
Is usually fed from a small container such as a 5 gallon can, via vacuum
hose Into a reservoir at the base of the lower roller. The coating is
picked up by the recessed dots, held In by the liquid's surface tension,
and then transferred to the hide upon Impact. The pitted roller aids in
the uniform coating application to the leather.
The coating transfer efficiency of a roll coater can approach 1007. <
a tray beneath the rollers catches any unused coating and channels
back Into the feeder can. According to Pfister and Vogel (1986), re
coating requires only 201 of the material used in an equivalent
air-atomized spray application. After each coating,, the hide is subject
to either air or oven drying.
Technical problems such as lack of penetration, uneven applications, and
bunching of hides (particularly thinner ones) have limited the use of
roll coating equipment. However, with experience and improvement, this
economical technology has been gaining in use in the leather coating
industry.
Each hide is subjected to several different coatings. The three general
types of applications are called base, intermediate, and finishing
coats. The base coat is usually applied to the hide as a stain,
penetrator and flow aid. The primary purpose of intermediate coats is
to promote and Improve the adhesion properties of the hide allowing for
Improved application of the finish or top coats. The intermediate coats
may also fine tune the hide's texture, color or print since penetration
and flow ability is also important here. The top coats give the leather
its desired gloss and resiliency. It is essential that these coatings
be applied in a series of thin layers rather than in one or two spreads
so that the drying and flexibility properties of the leather can be
maintained. The question of how many, and what types of materials that
are .sprayed onto any particurar piece of leather depends upon the type
of initial raw hide used and desired finished product.
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In the case of air-atomized spray systems, the various base,
Intermediate and final coating applications have a variety of names.
These different applications are sometimes referred to as follows:
"spray stain" (base)
"spray middle" (middle)
"spray effect (1st top coat), and
"spray lacquer" (2nd top coat)
'spray lacquer" (2nd
Each of these different coating types pertains to the type of material
that 1s being used (I.e., "stain", "middle", "lacquer", or "effect").
Many leathers are not subject to each of these.finishes. Some leathers
receive more than one coat of certain finishes. As stated earlier, each
coating system can be highly Individualistic.
In the final stage, the completed material 1s measured, graded and
shipped to the appropriate leather goods manufacturing facility for
final production fabrication.
3.2.3 Coating Formulations
The Department surveyed the tanneries of southeastern Wisconsin during
1984 and found that each tannery maintains an extensive variety of
coatings in its stock. The multitude of different hides, desired
colors, textures, conditions and finishes necessitate a large, varied
coating Inventory. The data collected during the Department survey
indicate that any particular coating falls Into one of three categories
as follows:
Strict lacquers. These resin-based coatings contain approximately
70-951 organic solvents (VOCs) by weight. The remaining material
are resins and pigments (i.e., the "solids"). The lacquers contain
three components; the coloring ingredient (pigments), additives, and
solvent. Pigments are finely divided organic or inorganic material
that imparts color. No known heavy metals or toxics are commonly
used In lacquer formulations. The additives, usually organic resins
and polymers serve as a binder (stabilizer) between pigment and the
leather substrate and give the coating the desired characteristics,
such as gloss and skuff resistance. The solvent is the medium in
which the additives are dissolved and dispersed to transfer the
pigment to the leather substrate.
Lacquer emulsions. These coatings are similar to strict lacquers
However a surfactant (e.g., sodium laural sulfate) is applied to the
material so that it can be water-misclble. The user then dilutes
the material with water in appropriate amounts. These coatings vary
from 20-301 water by weight and 5-151 solids by weight. The
remaining 55-751 of these emulsions are comprised of solvents. The
lacquer emulsions, which a/e water-miscible, are diluted with about
251 water by the leather coater before application.
Water-based coatings. These coatings contain less than 107. organ i:
solvents. This type of coating has-gained in use over the past re*
years as the technology has developed and use of these materials •M-;
improved. Their popularity is due to their increased
solids-carrying capability. With water-based coatings, less
"vehicle" is necessary to spread the solids onto the aides.
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Representative formulations for these various coatings along with their
typical costs are presented In Table 2. As Table I Indicates, the
solvent-based coatings are generally slightly less expensive than their
water-based counterparts.
Lacquers have the following advantages over water-based coatings:
They have much less surface tension, thus allowing a more uniform
spread and better penetration when applied. Water, with its higher
surface tension is a poor thinner that Is more likely to "bead" on
the product. Poor penetration Into the leather and reduced drying
capacity are also of concern with water-based coatings in some cases
There Is less sticking to the pVatlng machine during the embossing
or "plating" when the leather's texture Is being modified;
They give higher quality gloss to the finished leather; and
They Impact enhanced water resiliency and scruff-resistance.
Most of the advantages that solvent-based coatings have over their
water-based counterparts are at the top coat application stage where
gloss and resiliency must be well-established.
However, the water-based coatings have the advantage of being able to
hold more solids in the primary vehicle (water). Water-based coatings
can carry upwards of 501 more solids by weight. This can be important
in the base and Intermediate coating stages where much less water-based
coatings need be applied than comparable lacquers. Since gloss,
resiliency and other surface characteristics are of less concern at
these earlier coating applications water-based materials can and are
used here.
3.3 VQC Emission Rates
After the flow coating (if applied), the subsequent coatings are usually
applied to the leather by either a rotary nozzle sprayer or by a roll coater.
with the former being the predominant method in southeastern Wisconsin. Tne
rotary nozzle sprayer has been described In Section 3.2.2.
The leather coating process Involves a wide variety of hides, and tyqe, nu~oe
and thickness of coatings. As such, the Department decided to estimate VCC
emission rates based upon the amount of coating material, per each coating.
that would be applied to any one series of hides. The VOC emission rats u-n:
is kilograms per 100 square meters (kg VOC/IOOm') of leather for each
application. Each VOC emission factor would highlight the above-listed
variations.
In calculating VOC emissions from any uncontrolled surface coating operation .
it Is generally assumed that all VOCs contained In the coating evaporate i^
are eventually emitted into the ambient atmosphere. This assumption ;oui: :?
modified in light of conclusive evidence to the contrary.
C-58
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Table 2
Representative Leather Coating Formulations and Cost '"
Percent Content by Height
Ingredient Hater-based Lacquer Emulsions'"' Strict Lacquer
VOCS
Solids
Hater
Cost range
($/lb)
-------
The large Milwaukee area tanneries supplied VOC emission rate data to the
Department during late 1985 - early, 1986. This Information shows that there
Is a wide variation In the coating application among the leather finishers in
southeastern Wisconsin. One coater uses very little water-based materials and
no roll coating. Another facility needs to apply several extra coats to much
of Its leather to enhance the leather's scruff-resistance and waterproof
qualities for use In footwear manufacturing. Different coatings are sometimes
applied separately. On other occasions, various coatings are mixed together
and then applied. One tannery uses the roll coating technology primarily with
low solvent coatings; another employs similar equipment mostly with lacquers.
In general, there are numerous permutations and combinations of different
coating materials and methods of application In use In southern Hisconsin.
The result !s that there is a wide range in the.VOC emission rates. Table 3
presents some ranges for various coating systems (I.e., coating type and
application method) based on the information supplied by the leather finishers
to the Department during the past seven months. The numbers contained in
Table 3 highlight the wide variation In VOC emission rates from leather
coating operations.
3.4 Potential Leather Coating VOC RACT Measures and Cost
3.4.1 Low Organic Solvent/High Solids Coatings
VOC emissions from lacquers (over 801 VOCs) or .lacquer emulsion-based
coatings (over 50% VOCs) can be reduced by more than 50 percent by
employing coatings which have low levels of organic solvents (less than
201 VOCs). The actual VOC reduction achievable depends on the organic
solvent contents of the original coating and the proposed
alternatlve(s). Substituting low organic solvent or high solids
coatings is the accepted method to lower VOC emissions from all
Industrial surface coating operators.
Using a coating which has a low organic solvent content may preclude the
need for any further controls. In some cases, the coating equipment and
procedures may need not be altered when a plant converts to low solvent
coatings. This would keep the capital investment in coatings
substitution or reformulation to a minimum.
Because water-based and high solids coatings are a proven technology
that can feasibly reduce VOC emissions, the Department is proposing that
this type of coating constitutes a reasonably available control
technique for reducing VOC emissions from leather coating operations.
The Department is aware that product specification requirements can
often necessitate the continued use of high solvent coatings. Each type
of leather has Its own requirements that must be met. Each individual
coating system must be evaluated on a case-by-case basis as to whether
low solvent/high solids finishes can be adequately substituted.
3.4.2 Roll Coating
Roll coating, as stated in section 3.2.2, has become increasingly
popular In certain sectors of the leather finishing industry due to its
higher transfer efficiency (estimated to be close to 1001). Pfister arn
Vogel Tanning Company (1986) stated that roll coating applications
require only about 201 of the finishing material used in a comparable
air-atomized spray application.
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Table 3
VOC Emi ssion Rates
Various Coating Systems
Southeastern Wisconsin - 1985*
.Application Method Coating Type VOC Emission Rate (kg/100 m')
Flow Oil Impregnation ' 2.39-9.76
Air Atomized Spray Stain _ . 7.81-H.16
Air Atomized Spray Middle 0.33-6.41
Air Atomized Spray Emulsion 3.42"
Air Atomized Spray Effect (1st top coat) 1.95-12.7
Air Atomized Spray Lacquer (final top coat, sealer) 2.44-16.11
Roll Oil Impregnation 2.93"
Roll Stain 1.12-2.93
'Based upon information received from Amity Leather Products Co., Gebhardt-Vogel
Tanning Company, and Pfister & Vogel Tanning Company during November 1985 - April
1986.
"Only one value presented from the above listed leather finishers.
7634Q.PERM
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According to a midwest distributor of leather coating equipment, a
typical roll coater costs between $26,000 and S35.000 (year 1984
dollars, including installation and setup costs).
Assuming that roll coater's use one-fifth the finish of spray systems,
It is likely that a roll coating machine could pay for itself within ten
years of operation through reduced coating usage. After its payback
period, the equipment would give the company a net savings in reduced
coating costs. This benefit could occur even if depreciation and tax
write-off deductions are not included. A net zero cost of the equipment
over 10 years would imply that the ten year, gross annualized cost per
ton of VOCs reduced would also be zero. This compares quite favorably
with the cost of reducing VOCs for other surface coating categories
(Table 4>.
The high efficiency, relative simplicity, proven experience, and
anticipated capita! return of this equipment makes it a pragmatic
technique for reducing the amount of VOCs Into the atmosphere. As such,
the Department Is proposing that roll coating constitute a VOC
reasonably available control technique (RACT) for leather coating
operations. Roll coating would be a Department approved method to meet
compliance with any promulgated leather coating VOC emission limitation
control requirement.
In recommending roll coating as one VOC RACT for leather finishing, the
Department 1s aware that this method cannot be substituted for the
air-atomized spray method in all cases. Product specifications often
require the use of spraying. Because of the roll coater's considerable
savings in coating, It is to the leather finishers economic advantage to
continually investigate every- possible use of this technology in its
operations.
3.4.3 Microprocessor Controls on Air-Atomized Spray Equipment
The rotary arm sprayer has the potential for much overspray and
underspray on the hides passing below it. This unevenness in the
finishing application also results in much unnecessary solvent (and
VOC's) being emitted into the atmosphere. As such, the Department is
proposing that microprocessor controls (e.g., "electric eyes") on all
air-atomized spray equipment be a required VOC RACT for the leather
coater's. According to the Pfister and Vogel Tanning Company (1986),
rotary air atomized spray equipment without microprocessor controls
results In a typical transfer efficiency of 271. However, Pfister and
Vogel stated that the use of a microprocessor increases the efficiency
to 451. This results in a reduced coatings consumption by 407..
This equipment is relatively inexpensive to install and can pay for
Itself in reduced coating costs in several months. Indeed, most air
atomized spray systems used in the southeastern Wisconsin leather
coating industry are already fitted with these microprocessor controls.
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Table 4
Analyzed Estimated Cost (Year 1985 Dollars)
Per Ton of VOC Reduction
Industrial Surface Coating Categories
In Wisconsin that are Subject to RACT Adjusted from Booz-Allen's year 1978 dollar estimate to 1985 dollars by
assuming 401 Inflation in cost between these years.
7634Q.PERM
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3.4.4 Add-On Controls
Add-on VOC controls are post-process techniques that allow for the
venting and either destruction or removal of VOC's after the coatings
have been applied to the hides. Incinerator and carbon adsorbers wouic
be examples of add-on controls.
Add-on controls as a potential leather coating VOC RACT must be
evaluated In terms of annualIzed cost portion of VOCs reduced. These
calculations for a representative thermal Incinerator (no heat recovery
are based on equations developed by WAPORA (1981) and contained in
Table 5.
The gross ten-year annualIzed cost of an incinerator, as calculated in
Table 5, Is $144,230. Assuming an overall control efficiency of 857., a
source that approximates the parameters listed in Table 5 and emits 100
tons VOCs per year would pay $144,230/(0.85*100 tons) - $1,697/ton VOC
reduced. A two hundred ton/year VOC source with similar operating
specifications would pay $1697/2 - $848/to VOC reduced. However, it ca
be assumed that the larger the source, the more operation and
maintenance costs. The cost/VOC reduction factor Is not a constant
multiple of one baseline value. Nevertheless, the cost of reducing
leather coating VOC emissions is comparable when compared with similar
estimates for other surface coating operations (Table 4). The
Department, based upon the Information available to it, and th-e
subsequent calculations (Table 5). is recommending that thermal
incineration be considered on a case-by-case as VOC RACT.
At this time, the Department is also preliminarily recommending that
compliance with any promulgated leather coating VOC emission limitation
rule be achievable through the appropriate application of low-solvent
coatings, microprocessor controls on spray systems, and roll coating
technology alone. The status of this recommendation may change in ligh
of new data.
Carbon adsorption is not being recommended as VOC RACT for leather
coating. This type of system, which is approximately, three times as
expensive as a thermal incinerator of comparable size (WAPORA, 1981 ) ar
only feasible when much of the captured solvent can be recycled. The
multitude of different leather coating vented to a carbon adsorber maK;
such recovery system economically unfeasible since additional expensive
distillation would be required for any solvent recovery.
3.5 Proposed Leather Coating RACT VOC Emission Limitation Rule
3.5.1 Proposed VOC Emission Limits
As section 3.2 and 3.3 describe, the leather coating VOC emissions are
derived from a large number of permutations in the coating for-nulation
and application types. This wide variety of coating systems make it
difficult to succinctly define a VOC emission limitation or limitation
that would reflect an adequate implementation of RACT (section 3.4).
The absence of a U.S. EPA control technique gu.ideline (CTG) for this
category compounds the problems involved in setting VOC RACT limits fo
leather coating.
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Table 5
Estimated Annualized Cost
Thermal Incinerator (No Heat Recovery)
Leather Coating Facility
Assumptions
Representative air velocity In the vicinity of the coating equipment:
150 ft./min
Flow rate In vicinity of coating equipment:
150 ft/rain * 8 ft. (wide) * ft. (high) - 1200 ft.Vraln •
Operating Temperature: 1300*F - Temp.
VOC Cone. 1n gas stream: 50 ppm
Hours per year operation - 40 hrs/day * 260 days/yr - 2600 hrs/yr. actual
running time is 1300 hrs/yr. (0.5 * operating time)
Overall Control Efficiency: 851
/
Heat recover » 6
Base year (1981) fuel cost: S2.13/MMBTU'•' (#2 fuel oil)
Base year (1981) electrical cost: 50.055/kwh'a),
Inflation factor, year 1985 dollars to year 1981 dollars: 1.4,
Interest on equipment purchase loan: 181,
Full loan payment annually uniform in 10 years,
Deduction for depreciation, taxes and Interest not included, and
Installation Cost: 2.8 * unit cost (not including interest)18'
Calculations
1) Unit cost: $ « 2.7* flow rate + 22.000
- 2.7 * 12000 > 22,000
- 54,400 (year 1981 dollars)
2) Including factors for inflation and installation:
(1.4) * (2.8) ' $54,400 » $213,200
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Table 5 (Continued)
3) Total interest on the equipment and installation loan, assuming complete
uniform payment over ten years:
C
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The original draft rule had only one limit representing a composite of
various leather coating materials (water-borne, emulsions and lacquers) .
•and application types (spray and roll). Based upon comments received on
this first draft of the rule, the Department has striven to improve the
rule by establishing VOc limits that more accurately reflect the wide
variety of coating types.
The revised rule would establish VOC emission limits for each of the
basic functional coating types (Impregnation, stain, baseyor middle,
effect and finish coats) that are significant emitters of VOC's. It is
recognized that each of these function types (save for Impregnation) has
a somewhat Identifiable range of VOC emission rates for air-atomized
spray systems. Based on data received by the Department, qualitative
assessments of potential VX emission reductions have been projected fcr
each function type. These assessments_are based upon research and
testing with the available technology that Is proposed as RACT. These
projections are based upon the assumption that customer specifications
and state-of-the-art technology will remain essentially the same for the
Immediate future.
U.S. EPA CTG's recommended VX emission limits based, In part, upon
evidence that some facilities had already met these limits by applying
the categoryOspeclfic RACT. The Department has developed its leather
coating VX RACT limits in a similar manner. Namely, the Department
studied the total range of VOC emission rates foV each function type as
submitted by the leather coating facilities. Based upon these ranges
(minimum and maximum values are listed in Table 3),
determined that theJJ%*in each spray coating range
1-IStrioution; wou ia "represent an adequate degree of
words, the proposed VOC limits would be established
the Department has
(frequency
RACT. In other
at a level that is
currently being achieved about
coater's in the Milwaukee area.
161 of the time at the 3 largest leather
This standard translates into the proposed VOC RACT emission limitations
for the following categories (with accompanying proposed Department
defini tions):
Impregnation coat (penetration into the hide for tightening or
setting up the fibers. Also used for increased hide flexibility
without cracking)? A
VOCs/tOOm2) of
/ 2.9 kilograms VOCs per 100 square meters (2.9 kg
finished product, regardless of the number of impregnation coats
applied (6.0 pounds VOC per 1000 square feet - 6.0 Ibs VOCs/1000
fttf). _____— .
Stain coat (color development, or color deepening of the hide's
base): 9.3 kg VOCs/100m2 (19 Ibs VOC/1000 ft2) of finished product
regardless of the number of stain coats applied.
Base color coat (gives the leather its predominant color It
follows any impregnation and/or stain coats, or precedes any effect
or final finish coats): 1.0 kg VOCs/100m2 (2.0 Ibs VOCs/1000 ft2>
of finished product, regardless of the number of base color coats
applied.
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Effect coat (tonesV the base color and reduces the leather's surfac-
coefflclent of friction): 2.0 kg VOCs/100m2 (4.0 ibs VOCs/1000 ft2
of finished product, regardless of the number of effect coats
applied, and
Final finish coat (to help improve the leather's gloss,
water-resistance and scruff-reslstence qualities): 3.4 kg VOCs/lOOC
ft2) of finished product, regardless of the number of final finish
coats applled.
The Department Is aware that each finished leather product Is subject tc
one, and only one application of the above-listed coating types. Some
leathers receive several applications of one coat, others experience
none at all of certain coats, while still other leathers receive coats
that are not even contained in any of the above-1listed coating
categories. The Department has defined these categories and subsequent
VOC emission limits based upon a fair statistical representation of the
major VOC - emitting spray lines. Some other coating function types
(e.g., seasoning) result in negligible amounts of VOC emissions. 8y
controlling the amount of VOCs emitted from the five - previously listed
coating function types, the Department fully addresses the VOC emissions
concern In southeast Wisconsin's leather coating industry.
3.5.2 Proposed Rule Flexibility in Meeting the VOC Emission Limits
The purpose of this proposed rule is to help reduce the total amount of
ozone - precursor (VOCs) emitted into southeastern Wisconsin's
atmosphere. The separate limits listed in Section 3.5.1 reflect what
might be reasonably expected for each coating function type in achieving
this goal. However, the Department is aware that achieving each limit
for each product may be difficult. Furthermore, the leather coater's may
more readily comply with other certain application limits at certain
times. Subsequently, the proposed rule contains a subsection on
internal offsets (NR 422.17(03)) of VOC emission rates to meet the
facility's monthly-weighted allowable emission limit. Some of the
facility's specific leather coating production runs would be allowed to
exceed the RACT limit for any given month if the VOC emissions in excess
of that allowable for that month would be "offset" by VOC emissions from
other lines that are below their respective RACT limits for the same
month. Furthermore, the proposed leather coating VOC emission
limitations are expressed in units of kilograms VOC per 100 square
meters (kg/lOOmM of finished leather product regardless of the numoer
of specific coats applied. These emission rate units allow for maximum
flexibility in determining which RACT method(s) may be employed to
achieve the limit. Any combination of low solvent coating technology
roll coating, computer - controlled spray systems, incineration or any
other department - approved RACT method may achieve this primary
requirement of the rule. Subsection NR 422.04(1), His. Adm. Code
("Methods of Compliance") lists the VOC control options that would te
available to any leather coating facility subject to the rule.
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3.5.3 Recordkeeping and Reporting Requirements
Each affected facility will obviously have to closely monitor its
coatings usage, VOC emission totals, production totals, and methods of
compliance employed for all coating lines subject to the rule. This
monitoring must necessarily be done on a monthly basis to meet the
Internal offset provisions. In the short run, monthly production
schedules will need to be evaluated, possibly revised and closely
followed to ensure that the facility's overall monthly-weighted emission
rate Is not exceeded. Records of these activities must be maintained
and reported to the Department in accordance with proposed Chapter
NR 439 ("Compliance Demonstration") . whl'ch w.1 1 1 be proposed for adoption
approximately concurrently with this rule, but as part ofxdlfferent
Natural Resources Board order number. • /\
3.5.4 Proposed Compliance Schedule and Variance Provisions
The Department's commitment to develop, promulgate and implement all VOC
RACT rules Include the provision of certified final compliance for each
affected facility not later than December 31, 1987. This date 1s the
same as the ozone attainment deadline for the southeastern Wisconsin
ozone nonattainment area. Each stationary sources subject to any RACT
must achieve compliance with the appropriate rule before this date in
order for the region to take certified credit for the subsequent VOC
reductions. These VOC reductions are required under the 1982 Ozone
State Implementation Plan for 'southeastern Wisconsin.
If this proposed rule is promulgated, it will be done so at a late date,
relative to the December 31, 1987 deadline. On the other hand, much (if
not most) of the technology necessary to achieve compliance is already
in place for the affected leather coating facilities. It would be a
matter of improving and enlarging the role of these VOC emission control
technologies to meet the rule requirements. As such, the Department
believes that this rule can be coupled with in the required timeline
(i.e., before December 31, 1987) by meeting the following compliance
schedule, as measured from the effective date of the rule:
Submit final plans for achieving compliance within 4 months,
Award contracts for equipment modifications or issue orders for the
purchase of component parts to accomplish equipment modifications
within 5 months ,
Commence construction or installation of equipment modifications
within 7 months, and
Achieve final compliance not later than December 31, 1987.
This schedule is somewhat tighter than that required in previous VOC
RACT rules. However, any affected facility that believes it can not
meet this schedule, or any othej" provi sion( s)- in the rule, may apply for
a variance under section NR 43^.05.
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3.5.5 Estimated Impact of the Proposed Rule
1980 Is the base year for estimating the Impact of any RACT rule as part
of the 1982 ozone plan. Since that time, the southeastern Wisconsin
leather coater's have substantially Increased the efficiency of their
operations. Computer-controlled spray equipment, roll coating and low
solvent coatings either came into Initial use or were greatly expanded
In use during the first half of the 1980's at these tanneries. The
surge in foreign competition will further mandate continued improvements
1n their operations.
And most of these Improvements have and will continue to result in less
coating be applied to the leather. Less coating means fewer vocs
emitted. A prime example Is by simply employing computer controls on
spray lines, the amount of coating used has been reduced by 401 since
1980 (Pflster and Vogel (1980)). Furthermore, the leather coater's are
always seeking ways to expand their use of water-based coatings, which
are less costly than solvent-based coatings on per unit area basis. By
setting the VOC emission rates near the low end of the air atomized
spray ranges listed on Tgble 3, the Department has established goals
that are achievable by the affected facilities In the required timeline
(I.e., before December 31, 1987).
The projected Impact of this rule on the region's leather coating VOC
emissions can not be made at. this time. Currently, there is not enough
Information available to the Department to make this estimate. Such
calculations will be conducted when the affected facilities begin
supplying monthly records as part of Its rule compliance requirements.
The leather coating Industry is relatively complicated in understanding
its impact on VOC emissions. Developing VOC RACT and proposed rule for
this Industry has not been easy either. Subsequently, the rule's impact
will also take awhile to understand.
Both the energy and environmental Impacts (primarily industrial wastewater)
from leather coating operations are approximately proportional to the amount
of coating used. Since roll coating is more efficient than spray coating,
there would be a net reduction in energy consumption and process wastewater
when the former equipment is employed.
When substituting water-based coatings, there may be a slight increase in
energy consumption due to some additional oven-drying.
would be an Increase in natural gas consumption if thermal incineration
fllzed as a method to comply with any emission limitation. The impact 01
There
Is utilized as a method to comply with any emission limitation. The impact or
the environment from Increased natural gas usage would be negligence.
7634Q.PERM
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References
Booz,. Allen and Hamilton, Inc., 1978: Economic Impact of Implementing RACT '
Guidelines In the State of Wisconsin. Vol. 1, Executive Summary, Draft Final Report.
U.S. EPA, 1983: "Compilation of Air Pollution Emission Factors" AP-42.
Pfister and Vogel Tanning Company, April 29, 1986A* VOC Reduction Study Report.
Submitted to the Hisconsin Department of Natural Resources, Bureau of Air
Management.
Pfister and Vogel Tanning Company, 19868. July 1/1986 telephone conversation
between George Stockman, Manager, Research and Development, Pfister and Vogel and
Mr. William Adamski, Environmental Specialist, Wisconsin Department of Natural
Resources.
Wayne, W. S.; Wehrle, P. P.; and Carroll, R. E., 1967: "Qxidant Air Pollution and
Athletic Performance." Journal of the American Medical Association. 199:901.
United States Congress. 1977: The Federal Clean Air Act As Amended, August, 1977,
PL 95-95.
U.S. EPA, January 22, 1981: Federal Register. Vol. 46. pp. 7186.
U.S. EPA, September 17, 1979: Federal Register. Vol. 44. pp. 53782.
U.S. EPA, 1980: Environmental Impact Guidelines for New Source Leather Tanning and
Finishing Industries (EPA-130/6-8Q-QQ2). pp. 143.
WAPORA, Inc. 1981; Assessment of Organic Emissions In the Flexible Packaging
Industry. EPA-600/2-81-009. 85 pp.
Wisconsin Department of Natural Resources, 1983: 1982 Revision to the State
Implementation Plan for Ozone/Carbon Monoxide in Southeastern Wisconsin.
7634Q.PERM
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State of Massachusetts
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PUBLIC HEARING DRAFT
(22) _
Leather Surface Coatina
(a) Applicability. 310 CMR 7.18(22) applies in its entirety to
any person who owns, leases, operates or controls leather
surface coating line(s) which in total have the potential to
emit, before the application of air pollution control
equipment, equal to or greater than 50 tons per year of
volatile organic compounds.
(b) Reasonably Available Control Technology Requirements. On or
after July 1, 1993, unless exempted by 310 CMR 7.18(22)(c)
or granted a non-renewable extension by the Department, under
310 CMR 7.18(22)(d), no person subject to 310 CMR
7.18(22)(a) shall cause, suffer, allow or permit emissions
from any leather surface coating line in excess of 27.4 Ibs
VOC/gallon of solids applied.
(c) Exemptions. The requirements of 310 CMR 7.18(22)(b) do not
apply to:
1. a. any person subject to 310 CMR 7.18(22)(a) who
is able to demonstrate to the Department that,
since January 1, 1990, the leather surface coating
line(s) have not, in total, emitted, before the
application of air pollution control equipment,
greater than or equal to 50 tons per year of
volatile organic-compounds; and
b. provided the person obtains a permit
restriction from the Department under 310 CMR
7.02(12) which restricts the potential emissions
to below 50 tons per year; and
c. provided the person complies with other
sections of 310 CMR 7.18(22).
2. any person subject to 310 CMR 7.18(22)(a) who,
according to the Department, has complied with 310 CMR
7.18(17) prior to January 1, 1993.
(d) Extensions.
1. Any person subject to 310 CMR 7.18(22)(b) may apply in
writing to the Department for a non-renewable extension of
the implementation deadline. The person must apply to the
Department for the non-renewable extension at the same time
the person submits the emission control plan required by 310
CMR 7.18(20).
2. The Department will consider a non-renewable extension
of the deadline in 310 CMR 7.18(22)(b) until no later than
July 1, 1994, provided the emission control plan submitted
for approval 7.18(20), meets the following criteria in
addition to those of 310 CMR 7.18(20):
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PUBLIC HEARING DRAFT
a. the emission control plan must meet all
requirements of M.G.L.c. 211; and,
b. the emission control plan must be approved by a
Toxics Use Reduction Planner certified under
M.G.L.c. 211, or an employee of the facility must
be certified as a Toxics Use Reduction Planner?
and,
c, implementation of the plan must meet the emission
limitations of 310 CMR 7.18(22)(b) or achieve a
85% emissions reduction, whichever is greater,
without using add-on air pollution control
equipment, as calculated on a mass of VOC emitted
per gallons of solids or unit of production; and,
d. the emission control plan must also contain
contingency measures to meet the RACT emission
limitation in 310 CMR 7.18(22)(b); such measures
must automatically take effect if the emissions
reductions achieved by meeting the requirements of
M.G.L.c. 211 do not satisfy 310 CMR 7.18(22)(b).
(e) Plan ..Submittal Requirements. Any person who owns, leases,
operates or controls a leather surface coating line(s)
subject to 310 CKR 7.18(22)(a) must submit an emissions
control plan, and have the plan approved by the Department
under 310 CMR 7.18(20).
s>
(f) Continuous Compliance. Any person who owns, leases,
operates or controls a leather surface coating line(s)
subject to 310 CMR 7.18(22)(a) shall maintain continuous
compliance at all times with their approved emissions
control plan. Compliance averaging times will be met in
accordance with the requirements of 310 CMR 7.18(2) (a).
Demonstrations of compliance may include considerations of
transfer efficiency provided that the baseline transfer
efficiency is equal to or greater than 65%, and the transfer
efficiency test method is detailed in the emission control
plan (310 CMR 7.18(20)) approved by the Department.
(g) RecordXeepina Requirements. Any person who owns, leases,
operates or controls a leather surface coating line(s)
subject to 310 CMR 7.18(22)(a) shall prepare and maintain
daily records sufficient to demonstrate compliance
consistent with the applicable averaging time as stated in
310 CMR 7.18(2) (a). Records kept to demonstrate compliance
shall be kept on site for five years and shall be made
available to representatives of the Department and EPA in
accordance with the requirements of an approved emission
control plan (310 CMR 7.18(20) or upon request. Such
records shall include, but are not limited to:
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PUBLIC HEARING DRAFT
transfer efficiency test method is detailed in the emission ,
control plan approved by the Department.
(h) Recordkeeping Requirements. Any person who owns, leases,
operates or controls a coating line(s) subject to 310 CMR
7.18(21)(a) shall prepare and maintain daily records sufficient
to demonstrate compliance consistent with the applicable
averaging time as stated in 310 CMR 7.18 (2) (a)-. Records kept to
demonstrate compliance shall be kept on site for five years and
shall be made available to representatives of the Department and
EPA in accordance with the requirements of an approved emission
control plan (310 CMR 7.18(20)) or upon request. Such records
shall include, but are not limited to:
1. identity, quantity, formulation and density of
coating(s) used;
2. identity, quantity, formulation and density of any
diluent(s) and clean-up solvent(s) used;
3. solids content of any coating(s) used;
4. actual operational and emissions characteristics of the
coating line and any appurtenant emissions capture and
control equipment;
5. quantity of product processed;
6. any other requirements specified by the Department in
any approval(s) issued under 310 CMR 7.18(20) or. any
order(s) issued to the person.
(i) Testing Requirements. Any person who owns, leases, operates
or controls a coating line(s) subject to 310 CMR 7.18(21)(a)
shall, upon request of the Department, perform or have performed
tests- to demonstrate compliance with 310 CMR 7.18(21). Testing
shall be conducted in accordance with EPA Method 24 and/or Method
25 as described in CFR Title 40 Part 60, or by other methods
approved by the Department and EPA.
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PUBLIC SEARING DRAFT
1. identity, quantity, formulation and density of
coating(s) used;
2. identity, quantity, formulation and density of any
diluent(s) and clean-up solvent(s) used;
3. solids content of any coating(s) used;
4. actual operational and emissions characteristics of the
coating line and any appurtenant emissions capture and
control equipment;
5. quantity of product processed;
6. any other requirements specified by the Department in
any approval(s) issued under 310 CMR 7.18(20) or any
order(s) issued to the person.
(h) Testing Requirements. Any person who owns, leases, operates
or controls a leather surface coating line(s) subject to 310
CMR 7.18(22)(a) shall, upon request of the Department,
perform or have performed tests to demonstrate compliance
with 310 CMR 7.18(22). Testing shall be conducted in
accordance with -EPA Method 24 and/or Method 25 as described
in CFR Title 40 Part 60, or by other methods approved by the
Department and EPA.
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State of Illinois
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TT.T.TNOIS REGISTER
POLLUTION CONTROL BOARD
NOTICE OF PROPOSED AMENDMENTS
Section 218.920 Applicability
a}- The rcquircmcnto of this • Subpart shall apply to a source 'a
miaocllanooug fabricated product-manufacturing process
omioaion units whiah.-o.re not included within any of the
categories specified in Subparta D, E, F, H, Q, R, S, T,
V> X/ Y, Z or DD if the aouroc ia aubjcct to thia Cubpart.
A oouroo io aubjoot to thin Cubpart if it oontaina procoaa
omioaion units, — not regulated 'by- Subparto B, — S-, — F
(excluding Ccotion 210.204(1) of thia Tart), II (eucluding
Section 210.405 of thia Part), Q, n, C, T (excluding
Section 218.406 of thia Part), V, X, ¥, Z or DB of thia
Part; which an a group both!
3J- Have • maximum • theoretical cmiasions of 01 Mg-(100 tona)
or moro per calendar yoar of VOM if no air pollution
control equipment were uncd,
3-)- Are not limited to loan than 01 Mg (100 tons) of VOM
omigQiono per calendar year in the. abacnce' of air
pollution control equipment, — through production or
capacity limitations contained in a federally
enforceable permit or a CIP revision.
Maximum theoretical emission:
1) A source is subject to this Subpart if it contains
process emission units, not reorulated by Subparts B,
E. F (excluding Section 218.204(1). H (excluding
Section 218.405). 0, R, S, T, (excluding Section
218.486) V, X, Y. Z or BB of this Part; which as a
group both:
A) Have maximum theoretical emissions of 90.7 Mg (100
tons) or more per calendar year of VOM if no air
pollution control equipment were used, and
April 15, 1993 DRAFT-25TPY-46
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ILLINOIS REGISTER
POLLUTION CONTROL BOARD
NOTICE OF PROPOSED AMENDMENTS
Are not limited to less than 90.7 Ma ClOO j:ons) of
VOM emissions per calendar year in the absence of
air pollution control equipment, through
production or capacity limitations contained in a
federally enforceable permit or a SIP revision.
2) If a source is subject to this Subpart as provided
above, the requirements of this Subpart shall apply to
a source7s miscellaneous fabricated product
manufacturing process emission units which are not
included within any of the categories specified in
SuboartS B. E. F. H. 0. R. S. T. V. X. Y. Z. AA. BB.
OQ. RR. or TT.
b) Potential to emit;
lj A source is subject to this Subpart if it has the
potential to emit 22.7 Mg (25 tonsl or more of VOM per
year, in aggregate, from emission units that are:
A! Not regulated within Subparts B, E. Fr H, Q, R. _S,
T (excluding Section 218.486)L V/ X. Y. Z. or BB
of this Part, or
B.1 Not included within one of the following
categories: synthetic organic chemical
manufacturingsindustry fSOCMI) distillation, SOCMI
reactors,, wood furniture, plastic parts coating
Xbusiness_jnachinesl. plastic parts coating
(other), offset lithography, industrial
wastevater, autobodyrjrefinishing. SOCMI batch
processing, volatile organic liquid storage tanks
and clean-up solvents operations.
2.L If a source is subject to this Subpart, as provided
above, the reguirements of this Subpart shall apply to
a source1's miscellaneous fabricated product
manufacturing process emission units, which are not
included within:
Al Subparts B, E, F, H. Q. R. S, T, V, X, .Y. 2, AA.
BB, CC, DP, QO, RR or TT of this Part, or
B) One of the following categories: synthetic
organic chemical manufacturing industry (SOCMI)
distillation, SOCMI reactors, wood furniture,
plastic parts coating (business machines)-, plasric
parts •:->.!ting (other), offset lithography,
April 15, 1993 DRAFT-25TPY-47
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ILLINOIS REGISTER
POLLUTION CONTROL BOARD
NOTICE OF PROPOSED AMENDMENTS
industrial wastewater. autobodv refinishina. SOCMI
batch processing, volatile organic liquid storage
tanks and clean-up solvents operations.
tec) If a source ceases to fulfill the criteria of subsections.
(a) and Jb). above, the requirements of this Subpart shall
continue to apply to a miscellaneous fabricated products
manufacturing process emission unit which was ever subject
. to the control requirements of Section 218.926 of this
Part.
ed) No limits under this Subpart shall apply to emission units
with emissions of VOM to the atmosphere less than or equal
to 0.91 Mg (1.0 ton) per calendar year if the total
emissions from such emission units not complying with
Section 218.926 does- not exceed 4.5 Mg (5.0 tons) per
calendar year of this Part.
4e) For the purposes of this Subpart, an emission unit shall
be considered regulated by a Subpart if it is subject to
the limits of that Subpart. An emission unit is fte%
considered not regulated by a Subpart if it is not subject
to the limits of that Subpart, e.g., the emission unit is
covered by an exemption in the Subpart or the
applicability criteria of the Subpart are not met.
ef) For the purposes of this Subpart, uncontrolled VOM
emissions in the absence of air pollution control
equipment are the emissions of VOM which would result if
no air pollution control equipment were used.
(Source: Amended at 111. Reg. , effective ' )
Section 218.926 Control Requirements
Every owner or operator of a miscellaneous fabricated product
manufacturing process emission unit subject to this Subpart shall
comply with the requirements of subsection (a) , (b) or (c) of
this Section:
a) Emission capture and control techniques which achieve an
overall reduction in uncontrolled VOM emissions of at
least 81 percent from each emission unit, or
(Board Note: For the purpose of this provision, an
emission unit is any part or. activity at a source of a
type that by itself is subject to control requirements in
other Subparts of this Part or 40 CFR 60, incorporated by
April 15, 1993 DRAFT-25TPY-48
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ir.T.INOlS REGISTER
POLLUTION CONTROL BOARD
NOTICE OF PROPOSED AMENDMENTS
reference in Section 218.112, e.g., a coating line, a
printing line, a process unit, a wastewater system, or
other equipment, or is otherwise any part or activity at a
source.)
b) For coating lines-?-!,
IX %T_he daily-weighted average VOtt content shall not
exceed 0.42 kg VOM/1 (3.5 Ibs VOM/gal) of coating as
applied (minus water and any compounds which are
specifically exempted from the definition of VOM)
during any day. owners and operators complying with
this Ccction limitation are not required to comply
with Section 218.301 of this Part, or
2) For leather coatincr lines at a source where the
criteria of Section 218.920fa), are not met;
A) The VOM contained in staincoatings, other than
stain coatings applied to ^specialty leather, as
applied at the source in anv consecutive 12 month
period shall not exceed 10 tons; and
B) The total VOM content of all coatings, including
stains, as applied to a category of specialty
leather, shall not exceed 38 Ibs per 1000 square
feet of such specialty leather produced,
determined on a monthly basis, or
c) An alternative control plan which has been approved by the
Agency and approved by the USEPA as a SIP revision.
(Source: Amended at 111. Reg. , effective .)
April 15, 1993 DRAFT-25TPY-49
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Monterey Bay Unified Air Pollution Control District
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Rule 430: Leather Processing Operations 80Silver CJoud Court
Monterey, CA 93940
PART 1 GENERAL
1 . 1 Purpose
The purpose of this rule is to reduce the emissions of volatile
organic compounds (VOCs) into the atmosphere during the use,
application, or drying of VOC-containing leather treatment
materials and solvents used in leather ^process ing facilities,
operations, and processes.
1.2 Applicability
The provisions of this rule shall apply to all facilities,
operations, and processes where leather is treated with
volatile organic compounds or with materials that contain VOCs.
As of the date of adoption of this rule, Salz Leathers of Santa
Cruz is the sole affected source
~» &I •
1.3 Exemptions
There are no exemptions to the rule.
1.4 Effective Dates
1.4.1 The requirements of this rule shall be effective on the
date of adoption.
1.4.2 Effective dates for emission reduction measures are
given in sections 3.1 and 3.2 of this rule.
1.5 References
1.5.1 The requirements of this rule implement provisions of
the District Air Quality Management Plan of 1991.
1.5.2 The requirements of Sections 3.1 and 3.2 of this rule
are derived from Section 40918 (b) of the California Health
and Safety Code and Section 182 (b)(2) of the federal Clean
Air Act which require the use of the best available retrofit
control technology and reasonably available control
technology for the attainment of state and federal ambient
air quality standards for ozone.
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041593 Draft Rule 430;
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Monterey Bay Unified Air
Pollution Control District CONCFPT DRAFT ONT.Y
24580 Silver Cloud Court CONCEPT DRAFT ONLY
Monterey, CA 93340 REGULATION iv
PROHIBITIONS
PART 2 DEFINITIONS
2.1 Combined efficiency
The capture efficiency multiplied by the control efficiency of
capture and control equipment, expressed as overall weight
percent, to be used for compliance witn section 3.1 of this
rule.
2.2 Exempt organic compounds
Group III compounds as defined below.
2.3 Group I compounds
any organic compound which has been identified as a toxic air
contaminant including, but not limited to, methylene chloride.
2.4 Group II compounds
any stratospheric ozone depleting compound including, but not
limited to: 1,l,l-trichloroethane, trichlorofluoromethane (CFO
11), dichlorodifluoromethane (CFC-12), chlorodifluoromethane
(HCFC-22), l,l,l-trichloro-2,2,2-trifluoroethane (CFC-113), l-
chloro-l,l-difluoro-2-chloro-2,2-difluoroethane (CFC-114),
chloropentafluoroethane (CFC-115), 2,2-dichloro-l,l,l-
trifluoroethane (HCFC-123), 1,1-dichloro-l-fluoroethane (HCFC-
141b), l-chloro-l,l-difluoroethane (HCFC-142b), 2-chloro-
1,1,1,2-tetrafluoroethane (HCFC-124).
2.5 Group III compounds
any of the following: trifluoromethane (HFC-23), 1,1,1,2-
tetrafluoroethane (HFO134a), pentafluoroethane (HFC-125),
1,1,2,2-tetrafluoroethane (HFC-134), 1,1,1-trifluoroethane
(HFC-143a), 1,1-difluoroethane (HFC-152a), and the following
classes of perfluorocarbons: (a) cyclic, branched, or linear,
completely fluorinated alkanes? (b) cyclic, branched, or
linear, completely fluorinated ethers with no unsaturations;
(c) cyclic, branched, or linear, completely fluorinated
tertiary amines with no unsaturations; and (d) sulfur-
containing perfluorocarbons with no unsaturations and with
sulfur bonds only to carbon and fluorine.
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041593 Draft Rule 430:
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Monterey Bay Unified Air
CONCEPT DRAFT ONLY Pollution Control District
REGULATION IV
PROHIBITIONS Monterey, CA 93940
2 . 6 High-volume low-pressure spray
to spray a coating by means of a spray gun that operates
between 0.1 and 10.0 psig air pressure.
2.7 Leather treatment
any liquid material applied onto or impregnated into leather to
beautify, protect, or give a finished appearance or quality to,
the leather, including, but not limited to; lacquers r oils-,
resins, stains, and top coats.
2 . 8 Leather treatment process
any portion of an operation where leather treatment materials
are applied and/or cured, including material application and
the heating, drying or storage of treated leather.
2.9 Ozone depleting compounds
Group II compounds, as defined above.
2.10 Volatile organic compound (VOC)
any compound containing at least one atom of carbon, except:
methane, carbon monoxide, carbon dioxide, carbonic acid,
metallic carbides or carbonates, ammonium carbonate, and Group
I, Group II, and Group III compounds. When measured or
calculated, the VOC concentration of leather treatment
materials shall be expressed as the weight of VOCs per volume
of treatment material. The volume of treatment material shall
not include water or exempt solvents as defined. The oil
portion of oil treatment mixtures shall be considered
nonvolatile for the purpose of this definition.
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041593 Draft Rule 430:
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CONCEPT DRAFT ONLY
REGULATION IV
PROHIBITIONS
4nContro1 District
24580 Silver Cloud Court
Monterey, CA 93940
PART 3 REQUIREMENTS
3.1 Sources permitted to emit more than 250 tons per year
By no later than November 1, 1994, any leather processing
operation with permitted VOC emissions of five or more tons per
day or 250 or more tons per year shall,control emissions by the
use of control technology which achieves a combined efficiency
of 85 percent.
3.2 Sources permitted to emit less than 250 tons per year
By no later than November 1, 1993, any leather processing
operation with permitted VOC emissions of less than five tons
per day or less than 250 tons per year shall comply with the
following requirements:
3.2.1 Leather treatment materials shall be reformulated so
that the VOC content of each material does not exceed the
following limits in pounds per gallon of material as applied:
Material
Stain
Oil
Resin
Top coat
11/1/93
7.5
7.5
1.3
4.0
1/1/95
nJOl
o^!
1/1/96
rff
^
3.2.2 By no later than November 1, 1993, the following
methods shall be utilized to minimize VOC emissions: roll
coating for oil application and photoelectric spray
controlled spray guns for the application of other VOC-
containing treatments.
3.2.3 On or after November 1, 1995, a person or facility may
not apply leather treatment materials to leather unless the
material is applied with properly operating equipment,
according to proper operating procedures, and by the use of
one of the following methods: roll coating, flow coating, dip
coating, or photoelectric spray controlled high-volume low-
pressure spray.
3.3. Restricted reformulations
A leather treatment material shall not be reformulated with
Group I compounds (toxic air contaminants) or Group II
C-90
041593
Draft Rule 430:
-------
Monterey Bay Unified Air
Pollution Control District CONCEPT DRAFT ONLY ^ IV Ct
24580 Silver Cloud Court -~p f^f 1
Monterey, CA 93940 REGULATION iv i **^«.
PROHIBITIONS
compounds (stratospheric ozone depleting compounds) for the
purpose of compliance with this rule.
3.4 Restricted clean-up solvents
Group I or Group II compounds shall not be used as clean-up
solvents for leather treatment processes or equipment.
3.5 Storage in closed containers
All materials which contain VOCs, including, treatments,
solvents, and clean-up wastes, shall be kept in containers that
are closed except when filling or emptying.
3.6 Incidental emissions
All materials which contain VOCs, including media into
which VOCs have been absorbed or adsorbed by emissions control
devices and all forms of VOCs to be recovered, recycled or
disposed, shall be handled, stored and transported so that
emissions of VOCs to the atmosphere, soil, groundwater, or any
other environmental media are minimized.
PART 4 ADMINISTRATIVE REQUIREMENTS
4.1 Daily Material Usage Record
A Record of daily VOC usage shall be created and maintained for
each day that leather is processed.
4.1.1 The Record shall be in a format which is approved by the
District.
4.1.2 The Record shall be signed at the end of each shift or
at the end of each day by the responsible operator or
facility manager.
4.1.3 The Record shall be kept on a 24 hour daily basis and
made available upon request for inspection by the District
for two years from the date of each entry.
4.1.4 The Record shall provide the following data for each
day:
4.1.4.1 the amount of VOCs mixed, dispensed, and emitted
from each designated stock or brand name mixture,
C-91
041593 Draft Rule 430: 6
-------
Monterey Bay Unified Air
CONCEPT DRAFT ONLY Pollution Control District
REGULATION TV 24580 Silver Ooud Court
Kt.GuijA.LJ.uH iv Monterev PA Q3a/tn
PROHIBITIONS wonierey, u\ 93940
4.1.4.2 the amount of VOCs used and emitted as clean-up or
testing materials, and
4.1.4.3 a summation of the amount of VOCs emitted from all
operations in the facility.
4.2 Quarterly summary
A summary of daily emission amounts, tabulated monthly, shall
be submitted _quarterly.
4.3 Book of formulas
A book of designated leather treatment material formulas shall
be maintained at the facility and provided to the District upon
request. The book shall contain such treatment designations
and technical data sheets for stock and brand name chemicals
and mixtures used to formulate each designated treatment so
that the estimates of daily emissions may be verified.
PART 5 TEST METHODS
5.1 The VOC content of treatments and solvents shall be
determined using Method 24 of the U.S. Environmental Protection
Agency (40 CFR 60, Appendix A).
5.2 The quantity of exempt organic compounds in treatment
formulas and solvents shall be determined using California Air
Resources Board Test Method 432.
5.3 The control efficiency of air pollution control equipment
shall be determined using EPA Methods 2, 2A, 2C, or 2D for
measuring flow rates and EPA Methods 25, 25A, or 25B for
measuring the total gaseous organic concentrations at the inlet
and outlet of the control device.
5.4 The capture efficiency of control equipment shall be
determined according to the EPA protocol of Title 40, Code of
Federal Regulations, Part 52.741.
* * * * *
C-92
041593 Draft Rule 430;
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APPENDIX D
LEATHER TANNING AND FINISHING FACILITIES
D-i
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D.1 Introduction to Appendix D
This appendix lists all of the facilities known to be tanning or finishing leather.
Various sources were used to compile this list. These sources included emissions data
bases, State and local agency inventories, industry directories, conversations with
professionals in the leather industry, and published reports. Due to constant changes
within the industry, there may be some inadvertent omissions or inclusions of plants in
the list.
D-ii
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APPENDIX D - LEATHER TANNING AND FINISHING FACILITIES
CALIFORNIA
Salz Leathers, Inc.
1040 River Street, Box 1840
Santa Cruz, CA 95061
(408) 423-4470
COLORADO
Western Tanning Inc.
1454 Highway 50
Delta, CO 81416
(303) 874-7631
FLORIDA
Acme Sponge & Chamois Co, Inc.
855 E. Pine Street, Box 338
Tarpon Springs, FL
(813) 937-3222
IOWA
Oshkosh Tanning Co., Inc.
Industrial Park Road
Boone, IA 50036
(515) 432-8500
ILLINOIS
Gutmann Leather Co.
1511 W. Webster Ave.,
Chicago, IL 60614
(312) 348-5300
Horween Leather Company
2015 Elston Avenue
Chicago, IL 60614
(312) 772-2026
D-1
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Much Leather Company
1525 West Homer Street
Chicago, IL
MASSACHUSETTS
Carr Leather Company
500 Boston Street
P.O. Box 270
Lynn, MA 01903
(617) 599-2511
Bamet Corp.
58 Pulask Rd.
Peabody, MA 01960
Bond Leather Co., Inc.
Summit Industrial Park
Bldg. 38, Summit Street
Peabody, MA 01960
(508) 531-3227
Rex Finishing, Inc.
R 119 Foster St.
Peabody, MA 01960
(508) 531-2076
Richard Leather Co., Inc.
9 Webb Street, Box 868
Salem, MA 01971
(508) 745-5440
Salem Suede, Inc.
72 Flint Street
Salem, MA 01970
MAINE
Irving Tanning Co.
Main Street
Hartland, ME 04943
(207) 938-4491
D-2
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Camden Tanning Corp.
116 Washington St.
P.O. Box C
Camden, ME 04843
(207) 236-3394
Prime Tanning Co., Inc.
Sullivan Street
P.O. Box 713
Berwick, ME 03901
(207)698-1100
Wilton Tanning Company
Route 2 & 4
Wilton, ME
MARYLAND
W.D. Byron & Sons, Inc.
312 N. Conocoheague St.
Williamsport MD 21795
(301) 233-7500
MICHIGAN
Eagle Ottawa Leather Company
200 N. Beechtree Street
Grand Haven, Ml 49417
(616) 842-4000
Whitehall Leather Company
900 South lake Street
Whitehall, Ml 49461
(616) 893-1315
MINNESOTA
S.B. Foot Tanning Co.
Bench Street
Red Wing, MN 55066
(612) 388-4731
D-3
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MISSOURI
Blueside Companies
205 Florence Rd
St. Joseph, MO 64502
(816) 279-7468
Hermann Oak Leather Co.
4050 North First Street
St. Louis, MO 63147
(314)421-1173
NORTH CAROLINA
Lackawanna Leather Company
P.O. Box 939
Conover, NC 28613
(704) 322-2015
NEBRASKA
Lackawanna Leather Company
2420 Z Street
Omaha, NE 68107
(402) 734-2360
NEW JERSEY
Schwarz Leather Co.
400 Gotham Pkwy
Carlstadt, NJ 07072
UDO Finishing Company
49 Vesey Street
Newark, NJ 07105
Seton Company
849 Broadway
Newark, NJ 07104
(201) 485-4800
D-4
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American Leather Manufacturing Co.
219 Elizabeth Ave.
Rahway, NJ 07065
(201) 382-1700
NEW YORK
Colonial Tanning Corp.
8-10 Wilson Street
Box 1068
Gloversville, NY 12078
(518) 725-7190
Fashion Tanning Co., Inc.
6 Van Rd, P.O. Box 1220
Gloversville, NY 12078
(518) 733-7961
Leather Agent, Inc. Tannery
177W. Fulton Street
Gloversville, NY 12078
(518) 735-3777
Androme Leather Corp.
21 Foster Street
Gloversville, NY 12078
Fromglo Plant
91 Second Street
Gloversville, NY 12078
»
Independent Leather Mfg. Corp.
315-329 S. Main Street
Gloversville, NY 12078
(518) 725-9416
JBF Industries Inc.
41 W. 11th Ave
Gloversville, NY 12078
(518) 725-7414
D-5
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Pan American Tanning Corp.
318 W. Fulton Street
Gloversville, NY 12078
(518) 773-7565
Twin City Leather Co., Inc.
3-15 River Street
Gloversville, NY 12078
(518) 725-8113
Wood & Hide Leather Co., Inc.
68 Wood St., P.O. Box 786
Gloversville, NY 12078
(518) 725-7105
Classic Leather Sales Corp.
126 West Fulton St.
Johnstown, NY 12095
(518) 762-9294
Karg Brothers, Inc.
6-20 East Fulton St.
Johnstown, NY 12095
(518) 762-3148
Adirondac Leather Inc.
Fisher Avenue
Johnstown, NY 12095
Allied Split Corp.
422 N. Perry Street
Johnstown, NY 12095
Arrow Leather Finishing Co.
21-23 West St.
Johnstown, NY 12095
Gordon Finishing Co., Inc.
19 West State St.
Johnstown, NY 12095
Pearl Leather Finishers Inc.
Industrial Park
Johnstown, NY 12095
D-6
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Simco Leather Corp.
99 Pleasant Ave.
Johnstown, NY 12095
(518) 762-7100
Carville National Leather Corp.
Knox Avenue, P.O. Box 40
Johnstown, NY 12095
(518) 762-1634
H&J Leather Finishers, Inc.
312 N. Perry Street
Johnstown, NY 12095
K-Lynn Split Inc.
40-52 W. State St.
Johnstown, NY 12095
Peerless Tanning Co., Inc.
24 Briggs Street
Johnstown, NY 12095
Townsend Leather Co.
45-49 Townsend Ave.
Johnstown, NY 12095
OHIO
Conneaut Leather Inc.
West Adams St.
Conneaut, OH 44030-1160
(216) 593-5205
PENNSYLVANIA
Howes Leather Co., Inc.
Cooper Road
Curwensville, PA 16833
Garden State Tanning
Locust & Franklin Streets
Fleetwood, PA 19522
D-7
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Gunnison Brothers, Inc.
9041 Tanning Road
Girard, PA 16417-0327
(814) 774-5616
Leather Tech, Inc.
964 Postal Rd.
Allentown, PA 18103
Mercersburg Tanning
209 Oregon St.
Mercersburg, PA 17236
(212) 686-7666
Westfield Tanning Company
360 Church Street
Westfield, PA 16950
(814) 367-5951
Seton Company
Morton Road
Saxton, PA 16678
(814) 635-2937
TENNESSEE
Volunteer Leather Company
Kefauver Drive
Milan, TN 38358
(615) 367-8417
Lannom Tannery
Box 550
Tullahoma, TN 37388
(615) 455-2288
Tennessee Tanning Co.
915 N. Atlantic St., Box 967
Tullahoma, TN 37388
(615) 455-3441
Coey Tanning Co., Inc.
441 Bugscuffle Rd.
Wartrace, TN 33713
D-8
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TEXAS
S.B. Foot Tanning Co.
Schroetner Industrial Park
Cactus, TX 79013
(612) 388-4731
UTAH
Fox Valley Tanning, Inc.
633 West Center Street
North Salt Lake, UT 84054
(801) 298-3894
WISCONSIN
Berlin Tanning & Mfg, Co
235-T S. Wisconsin St.
Berlin, Wl 54923
(414) 361-1818
Cudahy Tanning Company
5043 S. Packard Ave
"Cudahy, Wl 53110
(414) 483-8100
Blackhawk Leather Ltd.
1000 West Bruce St.
Milwaukee, Wl 53204
(414) 671-2690
Gebhardt-Vogel Tanning Co.
2615 W. Greves Street
Milwaukee, Wl 53233
(414) 383-4818
Pfister & Vogel Tanning Co.
1513 N. Water St.
Milwaukee, Wl 53201
(414) 273-7160
Paul Flagg
1031 Maryland Avenue
Sheboygan, Wl 53082
D-9
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Thiele Tanning Co.
123 N. 27th Street
Milwaukee, Wl 53208
(414) 933-1526
Amity Leather Products Co.
742 Indiana Ave
West Bend, Wl 53095
(414) 338-6601
WEST VIRGINIA
Howes Leather Co., Inc.
Rt. 250
Frank, WV 24920
(304) 456-4898
D-10
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APPENDIX E
SELECTED CONTACTS
E-i
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E.1 Introduction to Appendix E
This appendix includes a list of selected contacts made during the development
of the report. This list is provided to assist State and local agency personnel in identifying
key professionals who may be of assistance in developing rules for leather tanning and
finishing facilities.
E-ii
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APPENDIX E. SELECTED CONTACTS
Environmental Protection Agency
Anne Arnold
EPA Region I
JFK Federal Building
Boston, MA 02203-2211
(617)-565-3166
Wendy Columbo
EPA Region IX
75 Hawthorne Street
San Francisco, CA 94105
(415)-744-1219
Iliam Rosario
Industrial Studies Branch
Office of Air Quality Planning and Standards
MD-13
Research Triangle Park, NC 27711
(919)-541-5308
Steve Rosenthal
EPA Region V
230 South Dearborn Street
Chicago, IL 60604
(312)-886-6052
Paul Truchan
EPA Region II
26 Federal Plaza
New York, NY 10278
(212J-264-2517
State and Local Agencies
Proveen Amar
NESCAUM
85 Merrimac Street
Boston, MA 02114
(617)-367-8540
E-1
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Steve Barlow
State of New York Region V
Hudson Street Extension
PO Box 220
Warrensburg, NY 12885
Gary Beckstead
State of Illinois EPA
2200 Churchill Road
Springfield, IL 62794-9276
(217)-524-4343
Dan Belik
Bay Area Air Quality Management District
939 Ellis Street
San Francisco, CA 94109
(415)-771-6000
Jim Coyle
State of New York
Environmental Conservation
50 Wolf Road, Room 138
Albany 12233
(518)-457-2044
Art Diem
State of New Jersey DEPA
CN027
Trenton, NJ 08625-0027
(609)-984-0490
Rich Driscoll
State of Massachusetts
Division of Air Quality
1 Winter Street, 7th Floor
Boston, MA 02108
(617)-292-5605
Steve Dunn
State of Wisconsin DNR
101 South Webster Street
Madison, Wl 53707-7921
(608)-267-0566
E-2
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Eric Flowers
State of Tennessee
Division of Air Pollution Control
701 Broadway, Customs House
Nashville, TN 37423-1531
(615)-532-0554
Jill Koebbe
State of Michigan
State Office Building, Suite 6D
350 Ottawa N.W.
Grand Rapids, Ml 49503
(616)-456-5071
John Krueger
State of Pensylvania
One Ararat Blvd.
Harrisburg, PA 17110
(717)-657-4587
Guy Neenan
Monterey Bay Air Quality Management District
24580 Silver Cloud Court
Monterey, CA 93940
(408)-647-9411
Cal Peters
State of Michigan
State Office Building, Suite 6D
350 Ottawa N.W.
Grand Rapids, Ml 49503
(616)-456-5071
Ron Severance
State of Maine Air Quality
State House Station, #17
Augusta, ME 04333
(207)-289-2437
E-3
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George Volpentesta
State of Wisconsin
DNR SE District {Milwaukee area)
PO Box 12436
Milwaukee, Wl 53212
(414)-263-8571
Leather Tanning and Finishing Industry
Wilhelm Bley
Lackawanna Leather Company
PO Box 939
Conover, NC 28613
(704)-322-2015
Peter Dykes
Mercersburg Tanning
209 Oregon St.
Mercersburg, PA 17236
(717)-328-3111
Paul Erickson
Environmental Manager
U. S. Leather Holdings
1110 North Old World Street, Suite 400
Milwaukee, Wl 53202
(414)-291-3042
Buz Haltenhoff
Environmental Manager
Eagle Ottawa Leather Company
200 N. Beechtree St.
Grand Haven, Ml 49417
(616)-842-4000
Charles S. Myers
Leather Industry of America, Inc.
1000 Thomas Jefferson St., NW
Suite 515
Washington, DC 20007
(202)-342-8086
E-4
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Frank Rutland
Tanner's Council Laboratory
ML 14
Cincinnati, OH 45221
(513)-556-1200
Dan Schedlar
Pfister & Vogel Leather Company
1531 North Water Street
PO Box 745
Milwaukee, Wl 53201
(414)-273-7160
Robert White
Executive Vice President
Eagle Ottawa Leather Company
200 N. Beechtree St.
Grand Haven, Ml 49417
(616)-842-4000
John Wittenborn
Collier, Shannon, Rill & Scott
3050 K Street, NW
Suite 400
Washington, DC 20007
(202)-342-8400
Carl Zipfel
Corporate Environmental Manager
Seton Company
2500 Monroe Blvd.
Norristown, PA 19403
(215)-666-9600
Equipment Suppliers
Mark Boynton
Hampton Machine Company
63 Epping Street
Raymond, NH 03077
(603)-895-4724
E-5
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Wayne Collard
Salem Industries
245 South Mill Street
South Lyon, Ml 48178
(313)-437-4188
Jerry Hunt
Sinks Manufacturing Company
9201 W. Belmont Avenue
Franklin Park, IL 60131-2887
(708)-671-3000
Jeff Machusek
REECO (Research-Cottrell)
PO Box 1500
Somerville, NJ 08876
(201)-538-8585
Greg Olsen
Graco
PO Box 1441
Minneapolis, MN 55440-1441
(800)-543-0339
Leather Finishing Chemicals and Supplies
Steve Ossaf
Stahl USA
26 Howley Street
Peabody, MA 01966-3599
(508)-531-0371
Lori Schneider
Prime Leather Finishes
205 S. Second Street
Milwaukee, Wl 53204
(414)-276-1668
Robert Welch
Prime Leather Finishes
205 S. Second Street
Milwaukee, Wl 53204
(414)-276-1668
E-6
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TECHNICAL REPORT DATA
ffteast read Instructions OH tkt revent be fort completing)
. H6POBT NO.
EPA-453/R-93-025
3. RECIPIENT'S ACCESSION NO.
4, TITLE AND SUBTITL*
Air Emissions and Control Technology for
Leather Tanning and Finishing Operations
5. REPORT DATE
June 1993
8. PERFORMING ORGANIZATION CODE
. AUTHORtS* ~
Barry F. Mitsch, Reeae H. Howie, Samuel C. McClintok
8. PERFORMING ORGANIZATION REPORT NO.
10. PROGRAM ELEMENT NO.
. PERFORMING ORGANIZATION NAME AND AOORESS
Alpha-Gamma Technologies, Inc.
900 Ridgefield Drive, Suite 350
Raleigh, NC 27609
11. CONTRACT/GRANT NO.
68-D1-0117, WA #79
12. SPONSORING AGENCY NAME AND AOORESS
U.S. Environmental Protection Agency (MD-13)
Emission Standards Division
Office of Air Quality Planning and Standards
Research Triangle Park. NC 27711
13. TYPE Of REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
19. SUPPLEMENTARY NOTES
ESD Work Assignment Manager:
Iliam D. Rosario, MD-13, 919-541-5308
16. ABSTRACT —~
This document was developed in response to an interest through the years from
the States and industries. The information has been obtained from available
literature, information provided through Federal, State, and local air pollxition
control agencies, and information obtained from the leather tanning and finishing
industry. This document provides information for use in assessing appropriate
measures to control volatile organic compound (VOC) emissions from leather
tanning and finishing facilities. It also provides a general description of
the industry; describes the key processes employed in manufacturing leather;
characterizes the emissions of VOC's and HAPs from the industry; describes
applicable emission reduction technologies; an.d finally, discusses current
State and local air pollution regulations affecting the industry.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS;OPEN ENDED TERMS
c. COSATi Field/Group
Air Pollution
Leather Tanning
Leather Finishing
VOC Emission Controls
VOC Emission Reduction
Regulations
18. DISTRIBUTION STATEMENT
Release Unlimited
19. SECURITY CLASS I Tins Report I
" Unclassified
NO. OF
271
20. SECURITY CLASS (Tltiipagtl
Unclassified
22. PRICE
EPA fftm 2220.1 (R«». 4-77) P««VIOUS EDITION is ossouere
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