EPA-450/2-89-013
August 1989
LOCATING AND ESTIMATING AIR EMISSIONS
FROM SOURCES OF PERCHLOROETHYLENE
AND TRICHLOROETHYLENE
By
Claire C. Most
Radian Corporation
Research Triangle Park, North Carolina
Contract Number 68-02-4392
EPA Project Officer: Anne A. Pope
U. S. ENVIRONMENTAL PROTECTION AGENCY
Office Of Air and Radiation
Office Of Air Quality Planning And Standards
Research Triangle Park, North Carolina 27711
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This -report has been reviewed by the Office of Air Quality Planning
and Standards, U. S. Environmental Protection Agency, and has been
approved for publication. Mention of trade names or commercial
products does not constitute endorsement or recommendation for use.
EPA 450/2-89-013
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TABLE OF CONTENTS
Section paqe
1 Purpose of Document 1
References for Section 1 4
2 Overview of Document Contents 5
3 Background 7
Trichloroethylene 7
Nature of Pol1utant 7
Overview of Production and Use 9
Perch! oroethyl ene 10
Nature of Pol 1 utant 10
Overview of Production and Use 13
References for Section 3 16
4 Emissions from Trichloroethylene and Perch!oroethylene
Production 17
Trichloroethylene Production 17
Process Descriptions 17
Emissions 22
Source Locations 27
Perchloroethylene Production 27
Process Descriptions 27
Emissions 31
Source Locations 35
References for Section 4 37
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TABLE OF CONTENTS (Continued)
Section
5
Page
Emissions from Industries Producing Trichloroethylene
or Perch!oroethylene as a By-product 39
Vinylidene Chloride Production 39
Process Descri pti on 39
Emissions 42
Source Locati ons 43
Ethylene Dichloride/Vinyl Chloride Monomer
Production 43
Process Descriptions 45
Emissions 50
Source Locations 54
References for Secti on 5 56
Emissions from Industries Using Trichloroethylene or
Perchl oroethyl ene as Chemi cal Feedstock 57
Chi orof 1 uorocarbon Product i on 57
Process Descri pti on 58
Emissions 60
Source Locati ons 63
Polyvinyl Chloride (PVC) Production 63
Process Description 63
Emissions 67
Source Locati ons 69
References for Section 6 72
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TABLE OF CONTENTS (Continued)
Section Page
7 Emissions from Industries Using Trichloroethylene and
Perch!oroethylene as Sol vent 75
Trichloroethylene and Perchloroethylene Use in
Organic Solvent Cleaning 75
Process Description 75
Emissions „ 77
Source Locations „ 84
Dry Cleaning 84
Process Description 85
Emissions 87
Source Locations 88
Paints, Coatings, and Adhesives 90
Aerosols 91
References for Secti on 7 92
8 Other Potential Sources of Trichloroethylene and
Perchloroethylene Emissions 95
Distribution Facilities 95
Pub!icly Owned Treatment Works (POTWs) 97
Unidentified or Miscellaneous Sources of
Tri chloroethylene and Perchloroethylene 98
References for Section 8 100
9 Source Test Procedures 103
References for Section 9 105
APPENDIX A - Derivation of Emission Factors A-l
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VI
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LIST OF TABLES
Table Page
1 Physical and Chemical Properties of Trichloroethylene 8
2 Physical and Chemical Properties of Perchloroethylene 12
3 Trichloroethylene and Perchloroethylene Emission Factors
for an Existing Plant Producing Trichloroethylene by
Ethylene Bichloride Chlorination 25
4 Trichloroethylene and Perchloroethylene Emission Factors
for an Existing Plant Producing Trichloroethylene and
Perchloroethylene by Ethylene Dichloride
Oxychlorination 26
5 Domestic Producers of Trichloroethylene in 1988 28
6 Emission Factors for the Release of Perchloroethylene
from Perchloroethylene Production by Ethylene
Dichloride Chlorination 33
7 Emission Factors for the Release of Perchloroethylene
from Perchloroethylene Production by Hydrocarbon
Chlorinolysis Process 34
8 Domestic Producers of Perchloroethylene in 1988 36
9 Domestic Producers of Vinylidene Chloride in 1988 44
10 Trichloroethylene and Perchloroethylene Emission Factors
for Three Plants Producing Ethylene Dichloride/Vinyl
Chioride Monomer 53
11 .Domestic Producers of Vinyl Chloride Monomer in 1988 55
12 Estimated Controlled and Uncontrolled Perchloroethylene
Emission Factors for Existing Facilities Producing
Chlorofluorocarbon 113 and 114 62
13 Facilities Producing Chlorofluorocarbons 113, 114, 115,
and/or 116 in 1988 64
14 Potential Emission Controls for PVC Plants 68
15 Facilities Producing Polyvinyl Chloride Resins in 1988 70
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LIST OF TABLES (Continued)
Table
16
17
18
19
A-l
Page
Trichloroethylene and Perchloroethylene Emission Factors
for Organic Solvent Cleaning: Schedule A 80
Trichloroethylene and Perchloroethylene Emission Factors
for Organic Solvent Cleaning: Schedule B 82
Emission Factors for the Perchloroethylene Dry Cleaning
Industry 89
Summary of Major Trichloroethylene and Perchloroethylene
Di stri butors „ 95
Trichloroethylene and Perchloroethylene Emission
Factors for Equipment Leaks from Selected
Production Processes A-6
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vi ii
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LIST OF FIGURES
Figure paqe
1 Chemical use tree for trichloroethylene .„ 11
2 Chemi cal use tree for perch! oroethyl ene 15
3 Basic operations that may be used for trichloroethylene
(TCE) and perch!oroethylene (PCE) production by
ethylene dichloride (EDC) chlorination 19
4 Basic operations that may be used for trichloroethylene
(TCE) and perchloroethylene (PCE) production by
ethylene dichloride (EDC) oxychlorination 21
5 Basic operations that may be used for the production of
perchloroethylene by hydrocarbon chlorinolysis 30
6 Basic operations that may be used for vinylidene chloride
production from 1,1,2-trichloroethane 41
7 Basic operations that may be used for ethylene dichloride
production by the balanced process, with air-based
oxychlorination 46
8 Basic operations that may be used for ethylene dichloride
production by the oxygen process (oxychlorination step) . 49
9 Basic operations that may be used for vinyl chloride
production by ethylene dichloride dehydrochlorination ... 51
10 Basic operations that may be used in the production of
CFC-113 and CFC-114 59
11 Basic operations for polyvinyl chloride production by
suspension process using trichloroethylene as a
reaction chain transfer agent „ 65
12 Schematic of a perchloroethylene dry cleaning plant 86
13 Integrated bag sampling train 104
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IX
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SECTION 1
PURPOSE OF DOCUMENT
The Environmental Protection Agency and State and local air pollution
control agencies are becoming increasingly aware of the presence of
substances in the ambient air that may be toxic at certain concentrations.
This awareness, in turn, has led to attempts to identify source/receptor
relationships for these substances and to develop control programs to
regulate emissions. Unfortunately, very little information is available on
the ambient air concentrations of these substances or on the sources that
may be discharging them to the atmosphere.
To assist groups interested in inventorying air emissions of various
potentially toxic substances, EPA is preparing a series of documents such as
this that compiles available information on sources and emissions of these
substances. Prior documents in the series are listed below:
Substance EPA Publication Number
Acrylonitrile EPA-450/4-84-007a
Carbon Tetrachloride EPA-450/4-84-007b
Chloroform EPA-450/4-84-007c
Ethylene Dichloride EPA-450/4-84-007d
Formaldehyde EPA-450/4-84-007e
Nickel EPA-450/4-84-007f
Chromium EPA-450/4-84-007g
Manganese EPA-450/4-84-007h
Phosgene EPA-450/4-84-007i
Epichlorohydrin EPA-450/4-84-007J
Vinylidene Chloride EPA-450/4-84-007k
Ethylene Oxide EPA-450/4-84-0071
Chlorobenzenes EPA-450/4-84-007m
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Substance EPA Publication Number
Polychlorinated Biphenyls (PCBs) EPA-450/4-84-007n
Polycyclic Organic Matter (POM) EPA-450/4-84-007p
Benzene EPA-450/4-84-007q
This document deals specifically with trichloroethylene and
perch!oroethylene. Its intended audience includes Federal, State and local
air pollution personnel and others who are interested in locating potential
emitters of these compounds and making gross estimates of air emissions
therefrom.
Because of the limited amounts of data available on some potential
sources of trichloroethylene and perch!oroethylene emissions, and since the
configurations of many sources will not be the same as those described
herein, this document is best used as a primer to inform air pollution
personnel about (1) the types of sources that may emit trichloroethylene and
perch!oroethylene, (2) process variations and release points that may be
expected within these sources, and (3) available emissions information
indicating the potential for trichloroethylene or perchloroethylene to be
released into the air from each operation.
The reader is strongly cautioned against using the emissions
information contained in this document to try to develop an exact assessment
of emissions from any particular facility. Because insufficient data are
available to develop statistical estimates of the accuracy of these emission
factors, no estimate can be made of the error that could result when these
factors are used to calculate emissions from any given facility. It is
possible, in some extreme cases, that order-of-magnitude differences could
result between actual and calculated emissions, depending on differences in
source configurations, control equipment, and operating practices. Thus, in
situations where an accurate assessment of trichloroethylene or perchloro-
ethylene emissions is necessary, source-specific information should be
obtained to confirm the existence of particular emitting operations, the
OES/064
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types and effectiveness of control measures, and the impact of operating
practices. A source test and/or material balance should be considered as
the best means to determine air emissions directly from an operation.
In addition to the information presented in this document, another
potential source of emissions data for perchloroethylene and
trichlbroethylene is the Toxic Chemical Release Inventory (TRI) form
required by Section 313 of Title III of the Superfund Amendments and
Reauthorization Act of 1986 (SARA 313).l SARA 313 requires owners and
operators of certain facilities that manufacture, import, process or
otherwise use certain toxic chemicals to report annually their releases of
these chemicals to any environmental media. As part of SARA 313, EPA
provides public access to the annual emissions data. The TRI data include
.general facility information, chemical, information, and emissions data. Air
emissions data are reported as total facility release estimates, broken out
into fugitive and point components. No individual process or stack data are
provided to EPA. The TRI requires the use of available stack monitoring or
measurement of emissions to comply with SARA 313. If monitoring data are
unavailable, emissions are to be quantified based on best estimates of
releases to the environment. The reader is cautioned that the TRI will not
likely provide facility, emissions, and chemical release data sufficient for
conducting detailed exposure modeling and risk assessment. In many cases,
the TRI data are based on annual estimates of emissions (i.e., on emission
factors, material balances, engineering judgment). The reader is urged to
obtain TRI data in addition to information provided in this document to
locate potential emitters of perchloroethylene and .trichloroethylene, and to
make preliminary estimates of air emissions from these facilities. To
obtain an exact assessment of air emissions from processes at a specific
facility, source tests or detailed material balance calculations should be
conducted, and detailed plant site information should be compiled.
JES/064
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For each major industrial source category described in Sections 4
through 8, example process descriptions and flow diagrams are given,
potential emission points are identified, and available emission factor
estimates are presented that show the potential for trichloroethylene and
. perch!oroethylene emissions before and after controls employed by industry.
Individual companies are named that are reported to be involved with either
the production or use of trichloroethylene or perchloroethylene based
primarily on trade publications.
The final section of this document summarizes available procedures for
source sampling and analysis of trichloroethylene and perchloroethylene.
Details are not prescribed nor is any EPA endorsement given or implied to
any of these sampling and analysis procedures. At this time, EPA has
not generally evaluated these methods. Consequently, this document merely
provides an overview of applicable source sampling procedures, citing
references for those interested in conducting source tests.
This document does not contain any discussion of health or other
environmental effects of trichloroethylene or perchloroethylene, nor does it
include any discussion of ambient air levels or ambient air monitoring
techniques.
Comments on the contents or usefulness of this document are welcomed,
as is any information on process descriptions, operating practices, control
measures and emissions information that would enable EPA to improve its
contents. All comments should be sent to:
Chief, Pollutant Characterization Section (MD-15)
Noncriteria Pollutant Programs Branch
U.S. Environmental Protection Agency
Research Triangle Park, N.C. 27711
JES/064
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SECTION 3
BACKGROUND
TRICHLOROETHYLENE
Nature of Pollutant
Trichloroethylene (TCE) is a colorless, sweet smelling, nonflammable
liquid at normal temperatures and pressures. Trichloroethylene is also
known as ethylene trichloride, trichloroethene, and trichlor. The structure
of TCE is illustrated below:
H Cl
\ /
C = C
/ \
Cl Cl
Physical and chemical properties of trichloroethylene are presented in
Table 1.
Trichloroethylene is miscible with most organic liquids including such
common solvents as ether, alcohol, and chloroform, but is essentially
insoluble in water. It is relatively volatile, with a vapor pressure of
7.6 kPa at 20°C. The lower explosive limit of the vapor in air is
11 percent, and the upper explosive limit is 41 percent.* The liquid does
not have a flash point.1'2
Trichloroethylene decomposes by atmospheric oxidation and degradation
catalyzed by aluminum chloride.1 The decomposition products include
compounds that are acidic and corrosive, such as hydrochloric acid. To
prevent decomposition, commercial grades of TCE contain stabilizers such as
amines, neutral inhibitor mixtures, and/or epoxides.1
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TABLE 1. PHYSICAL AND CHEMICAL PROPERTIES OF TRICHLOROETHYLENE
Property Value
Structural Formula: C2HC13, CHC1 - CC12
Molecular weight 131.39
Melting point, °C -87.1
Boiling point, °C 86.7
Density at 20°C, g/mL 1.465
Vapor pressure at 20°C, kPa (mmHg) 7.6 (57)
Viscosity (absolute) at 20°C, mPa S (=cP) 0.58
Surface tension at 25°C, mN/m (=dyn/cm) 26.4
Flash point (closed cup), °C None
Upper explosive limit in air, % by volume 41
Lower explosive limit in air, % by volume 11
Heat of formation, liquid, MJ/(kg mo!) 4.18
Heat of formation, vapor, MJ/(kg mo!) -29.3
Heat of combustion, MJ/kg 7.325
Solubility in water at 20°C, g/lOOg water 0.107
Solubility of water in trichloroethylene at 20°C,
g/lOOg trichloroethylene 0.0225
SOURCE: References 1 and 2.
JES/064 8
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The lifetime of TCE in the atmosphere is slightly over four days, where
atmospheric lifetime is defined as the time required for the concentration
to decay to 1/e (37%) of its original value.3 This relatively short
lifetime indicates that TCE is not a persistent atmospheric compound;
however, it is continually released to the atmosphere. The relatively short
lifetime of TCE should prevent long-range global transport of significant
levels of TCE. The major mechanism for destruction of TCE in the atmosphere
is reaction with hydroxyl radicals. '4 Some of the anticipated degradation
products include phosgene, dichloroacetyl chloride, and formyl chloride.3
Overview of Production and Use
The commercial production of trichloroethylene began in the United
States in 1925 for use as a metal degreasing and dry cleaning agent.1
Trichloroethylene is currently produced in the United States by two
companies at two manufacturing sites. Domestic production in 1987 was
about 91,000 Mg. Approximately 23,000 Mg of trichloroethylene were exported
and 4,500 Mg imported. Trichloroethylene production demand is expected to
decrease because of improved industry recycling practices involving TCE and
the availability of inexpensive imports. Since 1980, imports have risen
steadily and exports have fallen.
Trichloroethylene is produced domestically by two processes:
(1) direct chlorination of ethylene dichloride, and (2) oxychlorination of
ethylene dichloride. By varying raw material ratios, trichloroethylene can
be produced separately or as a coproduct of perch!oroethylene (PCE).1'6 Of
the two companies currently producing TCE, one company produces TCE
separately using the direct chlorination process (PCE is produced as a
by-product);, the other produces TCE and PCE as coproducts using the
oxychlorination process. ' Trichloroethylene may also be produced as a
by-product during vinylidene chloride or ethylene dichloride/vinyl chloride
monomer manufacture.
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Figure 1 presents a chemical use tree summarizing the production and
use of TCE. The major end use of TCE is as an organic solvent; for
industrial degreasing; about 85 percent of the TCE supply is used in vapor
degreasing and another 5 percent is used in cold cleaning.5 These processes
are used in many industrial processes such as the manufacture of
automobiles, electronics, furniture, appliances, jewelry, and plumbing
fixtures.
Approximately five percent of the TCE supply is used as a chain-length
modifier in the production of polyvinyl chloride (PVC).5 The remaining TCE
(5 percent) is consumed in other solvent and miscellaneous applications.
These applications include use (1) as a solvent in adhesive formulations;
(2) as a solvent in paints and coatings; and (3) in miscellaneous chemical
synthesis and solvent applications. '7
PERCHLOROETHYLENE
Nature of Pollutant
Perchloroethylene (PCE) is a colorless, nonflammable liquid with an
ethereal odor.'" The chemical name for perchloroethylene is
tetrachloroethylene; it is also known as tetrachloroethene and perc. The
structure of PCE is illustrated below:
Cl
\
Cl
Cl
C
\
Cl
Perchloroethylene is practically insoluble in water, but is miscible with
the chlorinated organic solvents and most other common solvents such as
ethanol, diethyl ether, and oils. It is a solvent for many substances,
including fats, oils and tars.9 At 20°C, PCE has a vapor pressure of
1.87 kPa (14 mmHg).'
properties of PCE.
Table 2 summarizes the physical and chemical
JES/064
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TABLE 2. PHYSICAL AND CHEMICAL PROPERTIES OF PERCHLOROETHYLENE
Property Value
Structural Formula: C2C14, ClgC•- CC12
Molecular weight 165.83
Melting point, °C -22.7
Boiling point, °C 121.2
Density at 20°C, g/mL 1.62260
Vapor pressure at 20°C, kPa (mmHg) 1.87 (14)
Viscosity at 25°C, mPa S (=cP) 0.839
Surface tension at 15°C, mN/m (=dyn/cm) 32.86
Heat of formation, liquid, kJ/(mol) 12.5
Heat of formation, vapor, kJ/(mol) -25
Heat of combustion at constant pressure
with formation of aq HC1, kJ/(mol) 679.9
Solubility in water at 25°C, mg/lOOg water 15
Solubility of water in perch!oroethylene at 25°C,
mg/120g perch!oroethylene 8
SOURCE: References 2 and 9.
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In the presence of light and air, perch!oroethylene slowly autooxidizes
to trichloroacetyl chloride. Stabilizers, such as amines or phenols,
inhibit the decomposition process to extend solvent life and protect
equipment and materials. Compared to other chlorinated ethanes and
ethylenes, PCE is relatively stable, and generally requires only small
amounts of stabilizers.^
The major mechanism that removes perch!oroethylene from the air is
reaction with hydroxyl radicals.3'4 The degradation products include
phosgene and chloroacetyl chlorides. The atmospheric lifetime of PCE is
estimated to range from 119 to 251 days, where atmospheric lifetime is
defined as the time required for the concentration to decay to 1/e (37%) of
its original value.3 The relatively long lifetime of PCE in the atmosphere
suggests that long-range global transport is likely. Monitoring data have
shown the presence of PCE in the atmosphere worldwide and at locations
removed from anthropogenic emission sources. Removal of PCE from the air
can also occur by washout.
Overview of Production and Use
Perch!oroethylene was first prepared in 1821 by Faraday from
hexachloroethane. Industrial production began in the United States in
about 1925. Perch!oroethylene is currently produced by four companies at
six locations. The total domestic production was about 200,000 Mg in
1987. The total imports of PCE in 1987 were 54,000 Mg/yr, and the total
exports were 27,000 Mg/yr.10 Perchloroethylene production demand is
expected to remain the same or decline slightly over the long term.
Perchloroethylene is produced domestically by three processes. These
are (1) the direct chlorination of ethylene dichloride, (2) the
oxychlorination of ethylene dichloride, and (3) hydrocarbon chlorinolysis.
In the first two processes, PCE can be produced separately or as a coproduct
of TCE with the raw material ratios determining the proportions of PCE and
TCE. In the third process, PCE is manufactured as a coproduct with carbon
JES/064 13
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tetrachloride. Perchloroethylene may also be formed as a by-product
g
during ethylene dichloride/vinyl chloride monomer manufacture. Perchloro-
ethylene is produced in purified, technical, USP, and spectrometric grades.
The various grades are produced for dry cleaning* technical, industrial, and
vapor-degreasing uses, respectively.
The current uses of PCE are listed in Figure 2, along with the
percentage of the total product devoted to each use. Perchloroethylene is
commercially important primarily as a chlorinated hydrocarbon solvent and as
a chemical intermediate. The major end use of PCE is as a dry cleaning
solvent. Perchloroethylene largely replaced carbon tetrachloride (which is
no longer used) in commercial, coin-operated, industrial and garment-rental
dry cleaning operations. Some PCE is also used in textile processing as a
scouring solvent and as a carrier solvent. Together these uses account for
about 50 percent of total domestic demand for PCE. Approximately
25 percent of the PCE supply is used as a chemical intermediate in chloro-
fluorocarbon production (mostly for chlorofluorocarbon 113). Another
15 percent is consumed in organic solvent cleaning operations such as vapor
degreasing and metal cleaning. The remaining 10 percent of the PCE supply
is primarily consumed in other solvent applications. These applications
include use (1) as a solvent in paints, coatings, and adhesives, (2) as a
solvent in aerosol formulations, and (3) in miscellaneous solvent
applications.
JES/064 14
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REFERENCES FOR SECTION 3
1. McNeil!, W. C., Jr. Trichloroethylene. (In) Encyclopedia of Chemical
Technology, 3rd ed. Volume 5. R. E. Kirk, D. F. Othmer, M. Grayson,
and D. Eckroth, eds. John Wiley and Sons, New York, New York. 1978.
pp. 745-753.
2. U.S. Department of Health and Human Services. NIOSH Pocket Guide to
Chemical Hazards. DHHS (NIOSH) Publication No. 85-114. National
Institute for Occupational Safety and Health, Cincinnati, Ohio.
1985.
3. Cupitt, L. T. Atmospheric Persistence of Eight Air Toxics.
EPA/600/3-87-004. U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina. 1987.
4. Cupitt, L. T. Fate of Toxic and Hazardous Materials in the Air
Environment. EPA-600/3-80-084. U.S. Environmental Protection Agency,
Research Triangle Park, North Carolina. 1980.
5. Mannsville Chemical Products Corp. Chemical Products Synopsis -
Trichloroethylene. Asbury Park, New Jersey. 1987.
6. Standifer, R. L., and J. A. Key. Report 4: 1,1,1-Trichloroethane and
Perch!oroethylene, Trichloroethylene, and Vinylidine Chloride. (In)
Organic Chemical Manufacturing, Volume 8: Selected Processes.
EPA-450/3-80-28c. U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina. 1980. pp. III-8 to 111-14.
7. U.S. Environmental Protection Agency. Survey of Trichloroethylene
Emission Sources. EPA-450/3-85-021. Office of Air Quality Planning
and Standards, Research Triangle Park, North Carolina. 1985.
8. U.S. Environmental Protection Agency. Survey of Perch!oroethylene
Emissions Sources. EPA-450/3-85-017. Office of Air Quality Planning
and Standards, Research Triangle Park, North Carolina. 1985.
9. Keil, S. L. Tetrachloroethylene. (In) Encyclopedia of Chemical
Technology, 3rd ed. Volume 5. R. E. Kirk, D. F. Othmer, M. Grayson,
and D. Eckroth, eds. John Wiley and Sons, New York, New York. 1978.
pp. 754-762.
10. Mannsville Chemical Products Corp. Chemical Products Synopsis -
Perch!oroethylene. Asbury Park, New Jersey. 1987.
11. Hobbs, F. D., and C. W. Stuewe. Report 2: Carbon Tetrachloride and
Perch!oroethylene by the Hydrocarbon Chlorinolysis Process. (In)
Organic Chemical Manufacturing, Volume 8: Selected Processes.
EPA-450/3-80-28c. U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina. 1980. pp. III-l to III-4.
JES/064 • ;. 16
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SECTION 4
EMISSIONS FROM TRICHLOROETHYLENE AND PERCHLOROETHYLENE PRODUCTION
Sources of atmospheric emissions of trichloroethylene and
perch!oroethylene related to their production are described in this section.
Process flow diagrams are included as appropriate and the specific streams
or vents in the figures are labeled to correspond to the discussion in the
text. Emission factors for the production processes are presented when
available and control technologies are described. It is advisable for the
reader to contact specific sources in question to verify the nature of the
process used, production volume, and control techniques in place before
applying any of the emission factors presented in this report.
TRICHLOROETHYLENE PRODUCTION
Trichloroethylene (TCE) i-s currently produced domestically by either
direct chlorination or oxychlorination of ethylene dichloride (EDC) or other
chlorinated ethanes. Trichloroethylene, C12C=CHC1, can be produced
separately or as a coproduct of perch!oroethylene (PCE), C12C=CC12, by
varying raw material ratios.1
Trichloroethylene was once manufactured predominantly by the
chlorination of acetylene. However, because of the high cost of acetylene,
EDC chlorination became the preferred method for producing TCE. No domestic
plants currently use the acetylene-based process to produce TCE.2
Process Descriptions
Ethylene Dichloride Chlorination Process--
The major products of the EDC chlorination process are TCE and PCE.
Hydrogen chloride (HC1) is produced as a by-product. The direct
chlorination process involves the reaction of EDC with chlorine to yield a
» •
JES/064 17
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crude product from which marketable-grade TCE and PCE are derived following
distillation and purification. The EDC/chlorine ratio determines which
product (TCE or PCE) will be produced in the greatest quantity. The
following chemical equation characterizes the EDC chlorination process:
400-450°
C1CH2CH2C1 + C12 > HC1 + C1?CCHC1 + C12CCC12
1 atm
EDC Chlorine TCE PCE
Basic operations that may be used in the production of TCE and PCE by
EDC chlorination are shown in Figure 3. Ethylene dichloride (Stream 1) and
chlorine (Steam 2) vapors are fed to a chlorination reactor. The
chlorination is carried out at a high temperature (400 to 450°C), slightly
above atmospheric pressure, without the use of a catalyst. Other
chlorinated C0 hydrocarbons or recycled chlorinated hydrocarbon by-products
1
may be fed to the chlorinator.
The product stream from the chlorination reaction consists of a mixture
of chlorinated hydrocarbons and HC1. Hydrogen chloride (Steam 3) is
separated from the chlorinated hydrocarbon mixture (Steam 4) and used in
other processes. The chlorinated hydrocarbon mixture (Stream 4) is
neutralized with sodium hydroxide solution (-Stream 5) and is then dried.
Spent caustic is transferred to a wastewater treatment plant.
The dried crude product (Stream 7) is separated by a PCE/TCE column
into crude TCE (Stream 8) and crude PCE (Stream 9). The crude TCE
(Stream 8) is fed to a TCE column, where light ends (Stream 10) are removed
overhead. Bottoms from this column (Stream 11), containing TCE and heavies,
are sent to the finishing column, where TCE (Stream 12) is removed overhead
and sent to TCE storage. Heavy ends (Stream 13) are combined with light
ends (Stream 10) from the TCE column and stored for eventual recycling.
The crude PCE (Stream 9) from the PCE/TCE column is fed to a PCE
column, where PCE (Stream 14) goes overhead to PCE storage. Bottoms from
JES/064 18
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this column (Steam 15) are fed to a heavy ends column. Overheads from the
heavy ends column (Stream 16) are recycled and bottoms, consisting of tars,
are incinerated.
Ethylene Bichloride Oxychlorination Process--
The major products of the EDC oxychlorination process are TCE, PCE, and
water. Side reactions produce carbon dioxide, hydrogen chloride, and
several chlorinated hydrocarbons. The EDC oxychlorination process is based
on the use of a single step oxychlorination where EDC is reacted with
chlorine and/or HC1 to from TCE and PCE. This reaction can be illustrated
by the following chemical equation:
C1CH2CH2C1 + C12
EDC
HC1
430°C
CuCl,
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TCE
PCE
The crude product contains 85 to 90 weight percent PCE plus TCE and 10 to
15 weight percent by-product organics. Essentially all by-product organics
are recovered during purification and are recycled to the reactor. The
process is very flexible, so that the reaction can be directed toward the
production of either PCE or TCE in varying proportions by adjusting the EDC
to HC1/C12 ratio.1
Figure 4 shows basic operations that may be used for EDC
oxychlorination. Ethylene dichloride (Stream 1), chlorine or hydrogen
chloride (Steam 2), oxygen (Stream 3), and recycled by-products are fed to a
fluid-bed reactor in the gas phase. The reactor contains a vertical bundle
of tubes with boiling liquid outside the tubes to maintain the reaction
temperature at about 425°C. The reaction takes place at pressures slightly
above atmospheric. Copper chloride catalyst is added continuously to the
tube bundle. The reactor product (Stream 4) is fed to a water-cooled
condenser and then a refrigerated condenser. Condensed material and
catalyst fines drain to a decanter. The noncondensed inert gases
JES/064
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(Stream 5), consisting of carbon dioxide, hydrogen chloride, nitrogen, and a
small amount of uncondensed chlorinated hydrocarbons, are fed to a hydrogen
chloride absorber, where HC1 is recovered by absorption in process water to
make by-product hydrochloric acid. The remaining inert gases are purged
(Vent A).1
In the decanter, the crude product (Stream 7) is separated from an
aqueous phase. The aqueous phase, containing catalyst fines (Stream 8), is
sent to a waste treatment plant (6). Crude product is fed to a drying
column where dissolved water is removed by azeotropic distillation. The
water (Stream 9) from the drying column is sent to the waste treatment plant
(G) and the dried crude product (Stream 10) is separated into crude TCE
(Stream 11) and crude PCE (Stream 12) in a PCE/TCE column.1
Crude TCE (Steam 11) is sent to a TCE column, where the light ends
(Stream 13) are removed overhead and stored for recycle. The bottoms
(Stream 14) are neutralized with ammonia and then dried to produce finished
TCE (Stream 15), which is sent to storage.
The crude PCE (Stream 12) from the PCE/TCE is fed to a heavy ends
column where PCE and light ends (Stream 16) are removed overhead. Heavy
ends (Stream 17), called "hex wastes," are sent to an organic recycle
system, where the organics that can be recycled (Stream 18) are separated
from tars, which are incinerated. The PCE and light ends (Stream 16) from
the heavies column are fed to a PCE column, where the light ends (Stream 20)
are removed overhead and sent to the recycle organic storage tank. The PCE
bottoms (Stream 21) are-neutralized with ammonia and then dried to produce
finished PCE (Stre.am 22) which is sent to storage.1
Emissions
The major sources of emissions from EDC chlorination are storage tanks,
equipment leaks (fugitives) and handling operations. Other potential
sources of emissions include process vents, equipment openings, and
JES/064 22
-------
secondary sources. Potential sources of TCE and PCE process emissions for
the EDC chlorination process (see. Figure 3) are the neutralization and
drying area vent (Vent A), which releases inert gases from the chlorine and
EDC feeds, and the distillation column vents (Vents B), which release
noncondensible gases. Storage emission sources (Vents C) include recycle
storage and product storage. Handling emissions (Vents D) can occur during
loading into drums, tank trucks, tank cars, barges, or ships for" shipment.
The majority of emissions from production of TCE and PCE from EDC
chlorination result from process fugitives or equipment leaks. Fugitive
emissions (E) occur when leaks develop in valves or in pump seals. When
process pressures are higher than the cooling-water pressure, VOCs can leak
into the cooling water and escape as fugitive emissions from the quench
area. One company reported that contaminant and immediate pickup procedures
are practiced to control fugitives. Secondary emissions can occur when
wastewater containing VOCs (including TCE and PCE) is sent to a wastewater
treatment system or lagoon and the VOCs evaporate (F). Another source of
secondary emissions is the combustion of tars in the incinerator where VOCs
are emitted with the flue gases (G).1'3
The major sources of emissions from EDC oxychlorination are equipment
leaks (fugitives) and secondary sources. Other potential emission sources
include process vents, storage tanks, handling operations, and relief device
discharges. In the EDC oxychlorination process (see Figure 4), the hydrogen
chloride absorber vent (Vent A), which releases the inert gases from the
oxygen, chlorine, and hydrogen chloride feeds, is a potential source of EDC
process emissions. Other potential sources of EDG process emissions are the
drying column vent (Vent B) and the distillation column vents (Vents C),
which release primarily noncondensible gases, and the TCE and the PCE
neutralizer vents (Vents D)., which relieve excess pressure of the nitrogen
pads on the systems. The process vents are typically controlled by water
scrubbers, and the relief vent is uncontrolled. Storage emission sources
(Vents E) are recycle storage and product storage tanks. At one facility,
the storage tanks are fixed roof tanks that range in size from
JES/064 23
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13,500 gallons to 430,000 gallons with an average size of 55,000 gallons.
The tanks are controlled by condensers with reported efficiencies ranging
from 75 to 77 percent. Handling emissions (F) can occur during product
loading into drums, tank trucks, tank cars, barges, or ships for shipment.
All of the handling operations except drum handling are controlled by
submerged pipe filling technology. Fugitive emissions (G) occur when leaks
develop in valves or in pump seals. Some of the fugitive emissions
resulting from pressure relief valves are controlled by rupture disks at one
facility. Secondary emissions (H and I) occur as described above for the
chlorination process (see Vents F and G in Figure 3). No controls are
reported for reducing secondary emissions. '
Table 3 presents TCE and PCE emission factors for the only existing
plant producing TCE by the EDC chlorination process (PCE is produced as a
by-product only). Table 4 presents TCE and PCE emission factors for the
only existing plant producing TCE and PCE as coproducts by the EDC
oxychlorination process. Each table lists various emission sources, the
control techniques used to reduce emissions from each source, and the
corresponding emission factor. The emission factors were derived from
estimates of the annual emission rate and the total production capacity for
each plant in 1983. >4'5 As such, the factors reflect the overall level of
control at each plant in 1983. The EPA does not have more recent data on
emissions or control devices at these plants.
The controls currently used at each plant may differ. For example,
process vent emissions could be reduced by as much as 98 percent through
incineration. Fugitive emissions could be reduced through an
inspection/maintenance (I/M) program. Storage tank emissions could be
reduced by installing internal floating roof tanks with primary and/or
secondary seals and by adding a refrigerated condenser system. The reader
is encouraged to contact plant personnel to confirm the existence of
emitting operations and control technology at a particular facility prior to
estimating emissions therefrom.
JES/064
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Source Locations
Table 5 presents a published list of major producers of TCE.
PERCHLOROETHYLENE PRODUCTION
Perch!oroethylene (PCE) is produced domestically by three processes.
Two of the processes involve the chlorination and oxychlorination of
ethylene dichloride (EDC) or other chlorinated hydrocarbons having two
carbon atoms. Perchloroethylene and TCE are manufactured separately or as
coproducts by the chlorination or oxychlorination process with the raw
material ratios determining the proportions of PCE and TCE.1
Perchloroethylene is also manufactured as a coproduct with carbon
tetrachloride by the chlorinolysis of hydrocarbons such as propane and
propylene.
Perchloroethylene was once manufactured predominantly by the
chlorination of acetylene. However, as acetylene production declined, EDC
chlorination and hydrocarbon chlorinolysis became the preferred methods of
production. No domestic plants currently use the acetylene-based method to
produce PCE.
Process Descriptions
Ethylene Dichloride Chlorination Process--
A discussion of the EDC direct chlorination process for producing PCE
and TCE is presented in the subsection titled TRICHLOROETHYLENE PRODUCTION.
A diagram of the process is shown in Figure 3.
Ethylene Dichloride Oxychlorination Process--
A discussion of the EDC oxychlorination process for producing PCE and
TCE is presented in the subsection titled TRICHLOROETHYLENE PRODUCTION. A
diagram of the process is shown in Figure 4.
JES/064 27
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TABLE 5. DOMESTIC PRODUCERS OF TRICHLOROETHYLENE IN 19883'6
Manufacturer Location Process
Dow Chemical, USA Freeport, TX Chlorination of Ethylene
Dichloride
PPG Industries, Inc. Lake Charles, LA Oxychlorination of Ethylene
Dichloride
NOTE: This listing is subject to change as market conditions change,
facility ownership changes, plants are closed down, etc. The reader
should verify the existence of particular facilities by consulting
current listings and/or the plants themselves. The level of PCE or
TCE emissions from any given facility is a function of variables
such as capacity, throughput and control measures, and should be
determined through direct contacts with plant personnel. These
operating plants and locations were current as of January 1988.
JES/064 28
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Hydrocarbon Chlorinolysis Process--
The majority of PCE produced in the United States is formed by the
hydrocarbon chlorinolysis process. This process involves the simultaneous
chlorination and pyrolysis of hydrocarbons in which chlorine is reacted with
chlorinated hydrocarbon derivatives or with a hydrocarbon such as methane,
ethane, propane, or propylene. The major products of the hydrocarbon
chlorinolysis process are PCE, carbon tetrachloride, and hydrogen chloride.
The process yields a crude product from which marketable PCE is derived
following distillation and purification. The reaction can be represented by
the following equations:
500°
C3H8 + C12 » C12C = CC1? + CC1. + HC1
cat * ' *
500°
C3H6 + C12 > C12C = CCU + CC1. + HC1
cat . c * . *
Basic operations that may be used in this process are shown in
Figure 5. Preheated hydrocarbon feed material (Stream 1) and chlorine
(Stream 2) are fed to a chlorinolysis reactor, which is a fluid-bed reactor
maintained at about 500°C.7 The reaction products, consisting of carbon
tetrachloride, PCE, HC1, and chlorinated hydrocarbon by-products (Stream 3),
pass through a cyclone for removal of entrained catalyst and then are sent
to a condenser. Uncondensed materials (Stream 4), consisting of hydrogen
chloride, unreacted chlorine, and some carbon tetrachloride, are removed to
the hydrogen chloride purification system. The condensed material
(Stream 5) is fed to a hydrogen chloride and chlorine removal column, with
the overheads (Stream 6) from this column going to hydrogen chloride
purification. The bottoms (Stream 7) from the column are fed to a crude
storage tank. Material from crude storage is fed to a distillation column,
which recovers carbon tetrachloride as overheads (Stream 8). The bottoms
(Stream 10) from the carbon tetrachloride distillation column are fed to a
JES/064 29
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PCE distillation column. The overheads (Stream 11) from the PCE
distillation column are taken to PCE storage and loading, and the bottoms
are incinerated.
The feed streams (Streams 4 and 6) to hydrogen chloride purification
are compressed, cooled, and scrubbed in a chlorine absorption column with
chilled carbon tetrachloride (Stream 9) to remove chlorine. The bottoms and
condensable overheads (Stream 12) from this column are combined and recycled
to the chlorinolysis reactor. Uncondensed overheads (Stream 13) from the
chlorine absorption column are contacted with water to produce a
hydrochloric acid solution. This solution is stored for eventual
reprocessing and use in a separate facility. Overheads from the absorber
and vented gases from by-product hydrochloric acid storage are combined
(Stream 14) and passed through a caustic scrubber for removal of residual
hydrogen chloride. Inert gases are vented from the scrubber.7
Emissions
The majority of PCE emitted from all three processes originate from
fugitive emissions. Storage tanks are the second largest source of PCE
emissions. Potential emission sources for the EDC chlorination and
oxychlorination processes are shown in Figures 3 and 4, respectively, and
are discussed in the TRICHLOROETHYLENE PRODUCTION subsection.
Potential emission sources for the hydrocarbon chlorinolysis process
are shown in Figure 5. Process emission sources originate at the carbon
tetrachloride and PCE distillation condensers and caustic scrubber
(Vents A). Fugitive emission sources (F) include process pumps, valves and
compressors. Corrosion problems caused by chlorine and hydrogen chloride
can increase fugitive emissions. Storage emission sources (B) are crude and
final product storage. Several facilities reported using fixed roof tanks;
a couple other facilities, however, considered storage tank information to
be confidential. Handling emissions (C) can occur during product loadings
into drums, tank trucks, tank cars, barges, or ships for shipment.
Secondary emissions of PCE can result from handling and disposal of process
JES/064 31
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waste liquids. Two sources of secondary emissions from the hydrocarbon
chlorinolysis process are the bottoms from the PCE distillation column (D),
commonly called hex wastes, and the waste caustic from the caustic scrubber
(E).7
Perch!oroethylene emission factors for the EDC oxychlorination process
are shown in Table 4 and discussed in the TRICHLOROETHYLENE PRODUCTION
subsection. Perch!oroethylene emission factors for PCE production by the
EDC chlorination and hydrocarbon chlorinolysis processes are shown in
Tables 6 and 7, respectively. For the EDC chlorination process, the
emission factors presented are based on two facilities for which emissions
information was available. Control information is considered confidential
and is not listed for either facility, except for control of handling
emissions by submerged fill pipes. Perch!oroethylene emissions could be
reduced by using condensers on process vents. For the chlorinolysis
process, the emission factors are based on five facilities. Emission
factors for each individual plant were derived from the estimated annual
emission rate and the estimated PCE production capacity for that plant in
1983. ' As such, the factors presented in Tables 6 and 7 reflect the
overall level of control at PCE production facilities in 1983. The EPA does
not have more recent data on emissions or control devices at these plants.
Individual plants vary in the number of emission points reported and
the types of controls used. Emissions from process vents can be controlled
by scrubbers; fixed roof tanks by installation of internal floating roofs
with primary and/or secondary seals and addition of refrigerated condenser
system; handling by use of submerged fill pipe technology; equipment
openings by purging/washing/cleaning prior to openings; fugitive sources by
employing an I/M program; and secondary sources by steam stripping and
incineration. The reader is encouraged to confirm the existence of emitting
operations and control technology at a particular facility prior to
estimating emissions therefrom.
JES/064 32
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TABLE 6. EMISSION FACTORS FOR THE RELEASE OF PERCHLOROETHYLENE
FROM PERCHLOROETHYLENE PRODUCTION BY ETHYLENE
DICHLORIDE CHLORINATION
Type of
Emission/Source
Emission Factor
a,b
Range
Average
Process Vents
Storage
Handling
Process Fugitivec'd
Equipment Openings6
Secondary
0.12
0.23
0.001
80 -
0.
0.0f -
-0.29 kg/Mg
-1.0 kg/Mg
- 0.051 kg/Mg
138 Mg/yr
003 kg/Mg
0.001 kg/Mg
0.21 kg/Mg
0.62 kg/Mg
0.026 kg/Mg
110 Mg/yr
0.003 kg/Mg
0.0005 kg/Mg
_....-_..,.. . ,.„„,,. w ,,, vv.1 inw wi i\y/ i -|y ICICI I»U N I I UVJ I Ctllld Ul TUC Clll I U LCU 06"
megagram of PCE production capacity.
Based on emission factors calculated for two facilities. Emission factors
for each facility were based on the estimated annual emission rate from
Reference 4 and the estimated PCE production capacity from Reference 5.
The emission factors reflect the total emission rate from both uncontrolled
and controlled sources at the two facilities in 1983. The number of emission
points and the types of controls used at each plant differs. The EPA does
not have more recent data on emissions or control devices at these plants
The reader is encouraged to contact plant personnel to confirm the existence
of emitting operations and control technology at a particular facility prior
to estimating emissions therefrom.
Fugitive emissions rate independent of plant capacity.
Based on the average emission factor method for estimating emissions from
equipment leaks. Used the equipment count provided by plants and SOCMI
equipment leak emission factors; represents a relatively uncontrolled
facility where no significant leak detection and repair programs are in
place to limit fugitive emissions. More accurate emission estimates can
be obtained by using other methods such as the leak/no-leak or the three-
strata emission factor method. These methods use other data described in
Protocols for Generating Unit-Specific Emission Estimates for Eaui oment
Leaks of VQC and VHAP (EPA-450/3-.M-mn) - u— ^ -
p
Uncontrolled; based on data from one plant only.
Value reported by facility.
JES/064
33
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TABLE 7. EMISSION FACTORS FOR THE RELEASE OF PERCHLOROETHYLENE
FROM PERCHLOROETHYLENE PRODUCTION BY HYDROCARBON
CHLORINOLYSIS PROCESS
Emission Factor3'
Type of
Emission/Source Range . Average
Process Vents <0.00004 - 0.20 kg/Mg 0.06 kg/Mg
Storage 0.013 - 0.69 kg/Mg 0.4 kg/Mg
Handling 0.03 - 0.89 kg/Mg 0.06 kg/Mg
Process Fugitive0 0.41 - 60 Mg/yrd 34 Mg/yrd
Equipment Openings 0.00006 - 0.054 kg/Mg 0.02 kg/Mg
Secondary 0.0025 - 0.013 kg/Mg 0.008 kg/Mg
Emission factors in terms of kg/Mg refer to kilograms of PCE emitted per
megagram of PCE production capacity.
Based on emission factors calculated for five facilities. Emission factors
for each facility were based on the estimated annual emission rate from
Reference 4 and the estimated PCE production capacity from Reference 5.
The emission factors reflect the total emission rate from both uncontrolled
and controlled sources at the five facilities in 1983. The number of
emission points and the types of controls used at each plant differs. The
EPA does not have more recent data on emissions or control devices at these
plants. The reader is encouraged to contact plant personnel to confirm the
existence of emitting operations and control technology at a particular
facility prior to estimating emissions therefrom.
°Fugitive emissions rate independent of plant capacity.
At one facility, fugitive emissions were estimated to be 0.41 Mg/yr based on
emissions testing. At four other facilities, fugitive emission estimates
ranged from 13.6 to 60 Mg/yr PCE. These estimates were based on the average
emission factor method for estimating emissions from equipment leaks. The
equipment counts provided by plants and SOCMI equipment leak emission factors
were used. More accurate emission estimates can be obtained by using other
methods such as the leak/no-leak or the three-strata emission factor method.
These methods use other data to obtain better emission estimates and are
described in Protocols for Generating Unit-Specific Emission Estimates for
Equipment Leaks of VOC and VHAP (EPA-450/3-88-010).
JES/064 : 34
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Source Locations
Table 8 presents a list of perchloroethylene production facilities,
their locations, and production process.
JES/064 35
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TABLE 8. DOMESTIC PRODUCERS OF PERCHLOROETHYLENE IN 1988
4,5
Manufacturer
Location
Process
Dow Chemical, USA
Occidental Petroleum
Corporation, Occidental
Chemical Corporation,
subsidiary; electro-
chemicals, detergent,
and specialty products
PPG Industries, Inc.
Chemicals Group
Vulcan Materials Co.
Vulcan Chemicals Div.
Pittsburg, CA
Plaquemine, LA
Deer Park, TX
Lake Charles, LA
Geismar, LA
Wichita, KS
Chlorinolysis
Chlorinolysis
Chiorination of Ethylene
Dichloride
Oxychlorination of Ethylene
Dichloride
Chlorinolysis
Chlorinolysis
NOTE: This listing is subject to change as market conditions change,
facility ownership changes, plants are closed down, etc. The reader
should verify the existence of particular facilities by consulting
current listings and/or the plants themselves. The level of PCE or
TCE emissions from any given facility is a function of variables
such as capacity, throughput and control measures, and should be
determined through direct contacts with plant personnel. These
operating plants and locations were current as of January 1988.
JES/064
36
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REFERENCES FOR SECTION 4
1. Standifer, R. L., and J. A. Key. Report 4: 1,1,1-Trichloroethane and
Perchloroethylene, Trichloroethylene, and Vinylidine Chloride. (In)
Organic Chemical Manufacturing Volume 3: Selected Processes.
EPA-450/3-80-28c. U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina. 1980. pp. III-8 to 111-14.
2. Mannsville Chemical Products Corp. Chemical Products Synopsis -
Trichloroethylene. Asbury Park, New Jersey. 1987.
3. U.S. Environmental Protection Agency. Survey of Trichloroethylene
Emission Sources. EPA-450/3-85-021. Office of Air Quality Planning
and Standards, Research Triangle Park, North Carolina. 1985.
4. U.S. Environmental Protection Agency. Survey of Perchloroethylene
Emission Sources. EPA-450/3-85-017. Office of Air Quality Planning
and Standards, Research Triangle Park, North Carolina. 1985.
5. SRI International. 1983 Directory of Chemical Producers. Menlo Park,
California. 1983.
6. SRI International. 1988 Directory of Chemical Producers. Menlo Park,
California. 1988.
•7. Hobbs, F. D., and C. W. Stuewe. Report 2: Carbon Tetrachloride and
Perchloroethylene by the Hydrocarbon Chlorinolysis Process. (In)
Organic Chemical Manufacturing, Volume 8: Selected Processes
EPA-450/3-80-28C. U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina. 1980. pp. III-l to III-4.
8. Mannsville Chemical Products. Chemical Products Synopsis -
Perchloroethylene. Asbury Park, New Jersey. 1987.
JES/064 37
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JES/064
38
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SECTION 5
EMISSIONS FROM INDUSTRIES PRODUCING TRICHLOROETHYLENE
OR PERCHLOROETHYLENE AS A BY-PRODUCT
This section discusses TCE and PCE emissions from two processes where
TCE and/or PCE are produced as a by-product. Trichloroethylene is produced
as a by-product and may be emitted from vinylidene chloride production.
Trichloroethylene and PCE are produced as by-products and may be emitted
during the production of vinyl chloride monomer by the balanced process.
Emission sources are identified and emission factors are presented as
available. The reader is advised to contact the specific source in question
to verify the nature of the process, production volume, and control
techniques used before applying any of the emission factors presented in
this report.
VINYLIDENE CHLORIDE PRODUCTION
Trichloroethylene is formed as a by-product in the manufacture of
vinylidene chloride (VDC). Vinylidene chloride is produced domestically by
the dehydrochlorination of 1,1,2-trichloroethane with sodium hydroxide.1
Two plants in the U.S. produce VDC; each of these produces a number of other
chlorinated hydrocarbons by a variety of processes.1'2
Process Description
Vinylidene chloride is produced by the action of caustic on
1,1,2-trichloroethane. The raw material 1,1,2-trichloroethane is produced
as a coproduct in the chlorination and oxychlorination of ethane, ethylene,
and ethylene dichloride (1,2,-dichloroethane) to produce chlorinated C?
JES/064 39
-------
o
species. The reaction for the dehydrochlorination of 1,1,2-trichloroethane
to produce VDC is as follows:
H Cl H Cl H Cl
\ / water \ / \ /
Cl - C - C - H + NaOH -*> C = C + NaCl + H00 + C = C
/ \ 100°C / \ 2 / \
H Cl H Cl Cl Ct
1,1,2-tri- sodium VDC TCE
chloroethane hydroxide
The reaction is carried out with 2 to 10 percent excess caustic arid product
yields range from 85 to 90 percent.
Basic operations that may be used in the production of VDC from
1,1,2-trichloroethane are shown in Figure 6. Concentrated sodium hydroxide
(Stream 1) is diluted with water (Stream 2) to about 5 to 10 weight percent
and is mixed with the 1,1,2-trichloroethane feed (Stream 3) and fed
(Stream 4) to the dehydrochlorination reactor. The reaction is carried out
in the liquid phase at about 100°C without catalysts. Because the aqueous
and organic reactants are not miscible, the reaction is carried out in a
liquid dispersion. The dehydrochlorination reactor is continuously purged
with nitrogen (Stream 5) to prevent the accumulation of monochloroacetylene
impurity in the product VDC. The nitrogen is discharged from Vent A.1
The VDC-containing product from the dehydrochlorination reactor
(Stream 6) is separated in a decanter into an aqueous phase (Stream 7) and
an organic phase (Stream 8). The aqueous phase, comprising a sodium
hydroxide/sodium chloride solution, is divided. One fraction (Stream 9) is
recycled (Stream 4) to the hydrochlorination reactor, and the other fraction
(Stream 10) is steam stripped to remove organics and is discharged to a
wastewater treatment system (Discharge F).1
The organics from the aqueous phase (Stream 11) are combined with the
organic phase from the decanter (Stream 8). The combined organics
(Stream 12) are fed to a drying column, where residual water is removed as a
OES/064 40
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bottoms stream (Stream 13). The water removed from the drying column is fed
to the stream stripper with the aqueous stream from the product decanter
(Stream 10).1
The organic stream from the drying column (Stream 14) is fed to a
distillation column, which removes unreacted 1,1,2-trichloroethane as
overheads (Stream 15). The unreacted trichloroethane is recycled to the
dehydrochlorination reactor. Purified VDC product, removed as bottoms from
the finishing column (Stream 16), is used onsite or stored in pressurized
tanks before being shipped to users.
Emissions
Trichloroethylene can be formed as a by-product during VDC production.
Potential sources of process emissions (Figure 6) are the dehydrochlori-
nation reactor purge vent (A) and the distillation column vents (B), which
release primarily noncondensible gases. Storage emissions (Source C) result
from the storage of VDC product and intermediates containing TCE. Handling
emissions (Source D) result from the loading of VDC into tank trucks and
railroad tank cars. Fugitive emissions (E) result from leaks in valves,
pumps, compressors, and pressure relief valves. When process pressures are
higher than the cooling water pressure, VOC can leak into the cooling water
and escape as fugitive emissions from the cooling tower. Secondary TCE
emissions can occur from desorption of VOCs during wastewater treatment.
1
Emissions of TCE in 1983 have been estimated for one VDC manufacturing
facility. The major source of TCE emissions at the facility was equipment
leaks (fugitive emissions). Using the average emission factor method for
estimating emissions from equipment leaks, uncontrolled fugitive emissions
were estimated to be about 2.3 Mg/yr TCE based on an equipment count
provided by the plant and SOCMI equipment leak emission factors.4 More
accurate emission estimates can be obtained by using other methods such as
the leak/no-leak or the three-strata emission factor method. These methods
use other data to obtain better emission estimates and are described in
JES/064
42
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Protocols for Generating Unit-Specific Emission Estimates for Equipment
Leaks of VOC and VHAP (EPA-450/3-88-010).
The plant reported that a monitoring system was already in place that
detected 75 to 80 percent of all equipment leaks.4 Insufficient information
was provided, however, to determine the effectiveness of the monitoring
system in controlling fugitive emissions. It was estimated that a formal
leak detection and repair program would reduce fugitive emissions by about
50 percent.
Trichloroethylene emissions from one process vent and one pressurized
storage tank at the facility were estimated to be 1 x 10"7 Mg/yr and
4 x 10" Mg/yr, respectively.4 The facility considers further information
regarding the process vent and storage tank to be confidential.4 Production
capacity data for the facility are also considered to be confidential.
Therefore, insufficient data are available to estimate TCE emission factors
for the process and storage vents at this facility. No TCE emissions from
other sources were reported. The EPA does not have more recent data on
emissions or control devices at this facility.
Vinylidene chloride production plants may vary in configuration and
level of control. The reader is encouraged to contact plant personnel to
confirm the existence of emitting operations and control technology at a
particular facility prior to estimating emissions therefrom.
Source Locations
Major vinylidene chloride producers and production locations are listed
in Table 9.^
ETHYLENE DICHLORIDE/VINYL CHLORIDE MONOMER PRODUCTION
Trichloroethylene and PCE may be formed as by-products during the
production of vinyl chloride monomer (VCM) by the balanced process. The
balanced process involves two steps. In the first step, ethylene dichloride
JES/064 43 ;
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TABLE 9. DOMESTIC PRODUCERS OF VINYLIDENE CHLORIDE IN 1988'
Manufacturer
Location
Dow Chemical, USA
Freeport, TX
PPG Industries, Inc.
Chemicals Group
Lake Charles, LA
NOTE: This listing is subject to change as market conditions change,
facility ownership changes, plants are closed, etc. The reader
should verify the existence of particular facilities by consul-
ting current listings and/or the plants themselves. The level of
TCE emissions from any given facility is a function of variables
such as capacity, throughput and control measures, and should be
determined through direct contacts with plant personnel. These
operating plants and locations were current as of January 1988.
JES/064
44
-------
(EDC) Is produced from ethylene and chlorine by direct chlorination, and
from ethylene and hydrogen chloride (HC1) by oxychlorination. In the second
step, EDC is dehydrochlorinated to yield VCM and by-product HC1. The
by-product HC1 from VCM production via the direct chlorination/dehydrochlor-
ination process is used in the oxychlorination/dehydrochlorination process.
Process Descriptions
Ethylene Dichloride Production--
The balanced process consists of an oxychlorination operation, a direct
chlorination operation, and product finishing and waste treatment operations.
The raw materials for the direct chlorination process are chlorine and
ethylene. Oxychlorination involves the treatment of ethylene with oxygen
and HC1. Oxygen for oxychlorination generally is added by feeding air to
the reactor, although some plants use purified oxygen as feed material.5
Trichloroethylene and PCE are formed as by-products of oxychlorination as
shown in the following equation:
C2H4 + HC1 + 0? * CICH-CH-Cl + C1CHCC1, + Cl.CCCl.,
* d CuCl9 2 2 222
EDC TCE PCE
Basic operations that may be used in a balanced process using air for
the oxychlorination step are shown in Figure 7. Actual flow diagrams for
production facilities will vary. The process begins with ethylene
(Stream 1) being fed by pipeline to both the oxychlorination reactor and the
direct chlorination reactor. In the oxychlorination reactor the ethylene,
anhydrous hydrogen chloride (Stream 2), and air (Stream 3) are mixed at
molar proportions of about 2:4:1, respectively, producing 2 moles of EDC and
2 moles of water. The reaction is carried out in the vapor phase at 200 to
315 C in either a fixed-bed or fluid-bed reactor. A mixture of copper
chloride and other chlorides is used as a catalyst.5
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The products of reaction from the oxychlorination reactor are quenched
with water, cooled (Stream 4), and sent to a knockout drum, where EDC and
water (Stream 5) are condensed. The condensed stream enters a decanter,
where crude EDC is separated from the aqueous phase. The crude EDC
(Stream 6) is transferred to in-process storage, and the aqueous phase
(Stream 7) is recycled to the quench step. Nitrogen and other inert gases
are released to the atmosphere (Vent A). The concentration of organics in
the vent stream is reduced by absorber and stripper columns or by a
refrigerated condenser (not shown in Figure 7).5'6
In the direct-chlorination step of the balanced process, equimolar
amounts of ethylene (Stream 1) and chlorine (Stream 8) are reacted at a
temperature of 38 to 49°C and at pressures of 69 to 138 kPa. Most
commercial plants carry out the reaction in the liquid phase in the presence
of a ferric chloride catalyst.5 Trichloroethylene and PCE are formed as
by-products in the following equation:
38-49°C
C2H4 + C12 —> C1CH2CH2C1 + CICHCCK + Cl-CCCU + HC1
FeCu tie.
EDC TCE PCE
Products (Steam 9) from the direct chlorination reactor are cooled and
washed with water (Stream 10) to remove dissolved hydrogen chloride before
being transferred (Steam 11) to the crude EDC storage facility. Any inert
gas fed with the ethylene or chlorine is released to the atmosphere from the
cooler (Vent B). The waste wash water (Stream 12) is neutralized and sent
to the wastewater steam stripper along with neutralized wastewater
(Stream 13) from the oxychlorination quench area and the wastewater
(Stream 14) from the drying column. The overheads (Stream 15) from the
wastewater steam stripper, which consist of recovered EDC, other chlorinated
hydrocarbons, and water, are returned to the process by adding them to the
crude EDC (Stream 10) going to the water wash.5
JES/064 47
-------
Crude EDC (Stream 16) from in-process storage goes to the drying
column, where water (Stream 14) is distilled overhead and sent to the
wastewater steam stripper. The dry crude EDC (Stream 17) goes to the heads
column, which removes light ends (Stream 18) for storage and disposal or
sale. Bottoms (Stream 19) from the heads column enter the EDC finishing
column, where EDC (Stream 20) goes overhead to product storage. The tars
from the EDC finishing column (Stream 21) are taken to tar storage for
disposal or sale.
Several domestic EDC producers use oxygen as the oxidant in the
oxychlorination reactor. Figure 8 shows basic operations that may be used
in an oxygen-based oxychlorination process as presented in the literature.
For a balanced process plant, the direct chlorination and purification steps
are the same as those shown in Figure 7, and therefore, are not shown again
in Figure 8. Ethylene (Stream 1) is fed in large excess of the amount used
in the air oxychlorination process, that is, 2 to 3 times the amount needed
to fully consume the HC1 feed (Stream 2). Oxygen (Stream 3) is also fed to
the reactor, which may be either a fixed bed or a fluid bed. After passing
through the condensation step in the quench area, the reaction products
(Stream 4) go to a knockout drum, where the condensed crude EDC and water
(Stream 5) produced by the oxychlorination reaction are separated from the
unreacted ethylene and the inert gases (Stream 6). From the knockout drums
the crude EDC and water (Stream 5) go to a decanter, where wastewater
(Stream 7) is separated from the crude EDC (Stream 8), which goes to
in-process storage as in the air-based process. The wastewater (Stream 7)
is sent to the steam stripper in the direct chlorination step for recovery
of dissolved organics.
The vent gases (Stream 6) from the knockout drum go to a caustic
scrubber for removal of HC1 and carbon dioxide. The purified vent gases
(Stream 9) are then compressed and recycled (Stream 10) to the oxychlori-
nation reactor as part of the ethylene feed. A small amount of the vent gas
(Vent A) from the knockout drum is purged to prevent buildup of the inert
gases entering with the feed streams or formed during the reaction.5
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Ethylene Dichloride Dehydrochlorination--
A typical flow diagram .for EDC dehydrochlorination is shown in
Figure 9. Ethylene dichloride (Stream 1) is introduced into the pyrolysis
furnace where it is cracked in the vapor phase at temperatures of 450 to
620°C and pressures of 450 to 930 kPa. About 50 to 60 percent conversion
of EDC to VCM is achieved in the reaction. The reaction is presented in
the following equation:
450-620°C
C1CH7CH9C1 > CH-CHC1 + HC1
* * 450-930 kPa z
EDC VCM
No PCE or TCI- are formed in this step.
The product gas stream from the furnace (Stream 2), containing VCM,
EDC, and HC1 is quenched with liquid EDC, and fed to a condenser. Hydrogen
chloride is removed from the condenser in the gas phase, and is recovered
for use onsite, generally in EDC production. The liquid stream from the
condenser (Stream 4) is fed to a distillation column, where it is separated
into VCM product, unreacted EDC, and heavy ends. The unreacted EDC
(Stream 5) is recycled either to the quench column or to the finishing
section of the EDC production process (generally onsite).6 The vinyl
chloride product is stored in pressurized vessels for eventual shipment to
polyvinyl chloride (PVC) plants or other facilities using vinyl chloride.
In instances where the PVC plant is very close to the vinyl chloride
producers, vinyl chloride can be delivered by pipeline.7 Heavy ends are
incinerated.
Emissions
Potential sources of TCE and PCE process emissions are the
oxychlorination vent (Vent A, Figures 7 and 8) and the direct chlorination
vent (Vent B, Figure 7). Other potential sources of process emissions are
gases released from column vents (Vent C, Figure 7), which include vents
JES/064 50
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from the wastewater steam stripper, the drying column, the heads column, and
the EDC finishing column. Many plants incinerate vent gases from the
oxychlorination reactor, direct chlorination reactor, and column vents to
reduce atmospheric emissions of volatile organics. ' »
Storage emission sources include in-process, liquid-waste stream, and
product storage (Sources D and E, Figures 7 and 8; source not shown in
Figure 9). Refrigerated condensation, compression, and/or incineration may
459
be used to control storage emissions. '' In addition, vinyl chloride
product is generally stored in pressurized tanks. Handling emissions may
occur during waste by-product loading operations. ' Fugitive emissions
(Source F in Figure 7) result from leaks in process valves, pumps,
compressors, and pressure relief valves. Secondary emissions can result
from the handling and disposal of process waste-liquid streams (Source G in
Figure 7).5
Table 10 presents TCE and PCE emission factors for three existing
EDC/VCM plants. The table lists various emission sources, the control
techniques used to reduce emissions from each source, and the corresponding
emission factor. The emission factors were derived from estimates of the
annual emission rate and annual VCM production capacity for each plant in
4 9—11
1983. ' The EPA does not have more recent data on emissions or control
devices at these plants.
Insufficient information was available to calculate TCE or PCE emission
factors for fugitive emissions at the three plants. Fugitive emissions of
TCE and PCE may be minor at EDC/VCM plants, however, because of control
measures which are taken to prevent emissions of vinyl chloride.
It is uncertain whether the emission factors for the three plants
presented in Table 10 are typical for the EDC/VCM industry. These plants
may vary in configuration and level of control. The reader is encouraged to
contact plant; personnel to confirm the existence of emitting operations and
control technology at a particular facility prior to estimating emissions
therefrom.
JES/064. 52 ,
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Source Locations
A list of vinyl chloride production facilities and locations is
presented in Table 11.
OES/064 54
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TABLE 11. DOMESTIC PRODUCERS OF VINYL CHLORIDE MONOMER IN 1988'
Manufacturer
Location
Borden Chemicals and Plastics
Dow Chemical, USA
Formosa Plastics Corporation, USA
Georgia Gulf Corporation
The BF Goodrich Company
BF Goodrich Chemical Group
Occidental Petroleum Corporation
Occidental Chemical Corporation, Subsidiary
PVC Resins and Fabricated Products
PPG Industries, Inc.
Chemicals Group
Vista Chemical Company
Geismar, LA
Oyster Creek, TX
Plaquemine, LA
Baton Rouge, LA
Point Comfort, TX
Plaquemine, LA
Calvert City, KY
La Porte, TX
Deer Park, TX
Lake Charles, LA
Lake Charles, LA
NOTE:
This listing is subject to change as market conditions change,
facility ownership changes, plants are closed, etc. The reader
should verify the existence of particular facilities by consul-
ting current listings and/or the plants themselves. The level of
TCE and/or PCE emissions from any given facility is a function of
variables such as capacity, throughput and control measures, and
should be determined through direct contacts with plant personnel.
These operating plants and locations were current as of January 1988
JES/064
•55
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REFERENCES FOR SECTION 5
1. Standifer, R. L., and J. A. Key. Report 4: 1,1,1-Trichloroethane,
Perch!oroethylene, Trichloroethylene, and Vinylidene Chloride. (In)
Organic Chemical Manufacturing, Volume 8: Selected Processes.
EPA-450/3-80-028c. U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina. 1980.
2. SRI International. 1988 Director of Chemical Producers. Menlo
Park, California. 1988.
3. U.S. Environmental Protection Agency. Locating and Estimating Air
Emissions from Sources of Vinylidene Chloride. EPA-450/4-84-007k.
Office of Air Quality Planning and Standards, Research Triangle Park,
North Carolina. 1985.
4. U.S. Environmental Protection Agency. Survey of Trichloroethylene
Emission Sources. EPA-450/3-85-021. Office of Air Quality Planning
and Standards, Research Triangle Park, North Carolina. 1985.
5. Hobbs, F. D., and J. A. Key. Report 1: Ethylene Dichloride. (In)
Organic Chemical Manufacturing, Volume 8: Selected Processes.
EPA-450/3-80-28c. U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina. 1980.
6. U.S. Environmental Protection Agency. Locating and Estimating Air
Emissions from Sources of Ethylene Dichloride. EPA-450/4-84-007d.
Office of Air Quality Planning and Standards, Research Triangle Park,
North Carolina. 1984.
7. TRW, Inc. Vinyl Chloride - A Review of National Emission Standards.
EPA-450/3-82-003. U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina. 1982.
8. U.S. Environmental Protection Agency. Locating and Estimating Air
Emissions from Sources of Carbon Tetrachloride. EPA-450/4-84-007b.
Office of Air Quality Planning and Standards, Research Triangle Park,
North Carolina. 1984.
9. U.S. Environmental Protection Agency. Survey of Perchloroethylene
Emission Sources. EPA-450/3-85-017. Office of Air Quality Planning
and Standards, Research Triangle Park, North Carolina. 1985.
10. SRI International. 1983 Directory of Chemical Producers. Menlo
Park, California. 1983.
11. Mannsville Chemical Products Corp. Chemical Products Synopsis - Vinyl
Chloride Monomer. Asbury Park, New Jersey. 1984.
JES/064 56
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SECTION 6
EMISSIONS FROM INDUSTRIES USING TRICHLOROETHYLENE
OR PERCHLOROETHYLENE AS CHEMICAL FEEDSTOCK
Emissions from industrial processes using TCE and/or PCE as a raw
material are described in this section. These processes include
chlorofluorocarbon production and polyvinyl chloride production.
CHLOROFLUOROCARBON PRODUCTION
Perch!oroethylene is used as a chemical intermediate in the synthesis of
CFC-113 (trichlorotrifluoroethane), CFC-114 (dichlorotetrafluoroethane),
CFC-115 (chloropentafluoroethane), and CFC-116 (hexafluoroethane). CFC-113
is used mainly as a solvent, but also as a refrigerant. The other CFC
compounds are used chiefly as refrigerants.1'2 The use of CFCs as aerosol
propel!ants was prohibited in 1979 because of their potential to contribute
to stratospheric ozone depletion.
CFC-113 and CFC-114 are co-produced as part of an integrated process
within the same facility. The only commercially important domestic process
used to produce these two compounds involves the liquid-phase catalytic
reaction of anhydrous hydrogen fluoride (HF) with PCE.3 A portion of CFC-114
produced by this method can be isolated for consumption in a separate
reaction with anhydrous hydrogen fluoride to yield CFC-115 and CFC-116.4
These reactions are illustrated by the following chemical equations:
45-200°C
100-3500 kPa
C!2CCC12 + HF + C12 —_ » C2C13F3 + C2C12F4 + HC1
5 CFC-113 CFC-114
C2C12F4 + C12 * C2C1F5 + C2F6 + HC1.
CFC-114 CFC-115 CFC-116
JES/064 57
-------
No other data were found on the CFC-115/CFC-116 production process or
emissions therefrom. Therefore, this section will focus on the production
of CFC-113 and CFC-114.
Process Descri pti on
Basic operations that may be used in the chlorofluorocarbon production
process are shown in Figure 10. Perch!oroethylene (Stream 1), liquid
anhydrous HF (Stream 2), and chlorine (stream 3) are pumped from storage to
the reactor, along with the recycled bottoms from the product recovery
column (Stream 15) and the HF recycle stream (Stream 9). The reactor
contains antimony pentachloride catalyst and is operated at temperatures
ranging from 45 to 200°C and pressures of 100 to 3,500 kPa.
Vapor from the reactor (Stream 4) is fed to a catalyst distillation
column, which removes hydrogen chloride (HC1), the desired fluorocarbon
products, and some HF overhead (Stream 6). Bottoms containing vaporized
catalyst, unconverted and underfluorinated species, and some HF (Stream 5)
are returned to the reactor. The overhead stream from the column (Stream 6)
3
is condensed and pumped to the HC1 recovery column.
Anhydrous HC1 by-product is removed overhead (Stream 7) from the HC1
recovery column, condensed, and transferred to pressurized storage as a
liquid. The bottoms stream from the HC1 recovery column (Stream 8) is
chilled until it separates into two immiscible phases: an HF phase and a
denser fluorocarbon phase. These are separated in a phase separator. The
HF phase (Stream 9), which contains a small amount of dissolved
fluorocarbons, is recycled to the reactor. The denser phase (Stream 10),
which contains the fluorocarbons plus trace amounts of HF and HC1, is
evaporated and ducted to a caustic scrubber to neutralize the HF and HC1.
The stream is then contacted with sulfuric acid and subsequently with
3
activated alumina to remove water.
JES/064 58
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The neutralized and dried fluorocarbon mixture (Stream 11) is compressed
and sent to a series of two distillation columns. CFC-113 is taken off the
bottom of the first distillation column and sent to pressurized storage
(Stream 13). The overheads from the first distillation (Stream 12) are sent
to the second distillation column, where CFC-114 is removed overhead and sent
to pressurized storage (Stream 14). The bottoms from the second distillation
(Stream 15) are recycled to the reactor. The actual configuration of the
distillation train for recovery of CFC-113 and CFC-114 may differ from the
two-column operation presented in Figure 10.
There are a number of process variations in chlorofluorocarbon
production. For example, HF is commonly separated from product
chlorofluorocarbons prior to hydrogen chloride removal. In addition, the
HC1 removal system can vary with respect to the method of removal and the
type of by-product acid obtained.
Emissions
No PCE emissions have been reported from process vents during
chlorofluorocarbon manufacture. Vents on the product distillation columns
emit only fluorocarbons. * ' A vent on the hydrogen chloride recovery
column accumulator purges noncondensibles and small amounts of inert gases
which enter the reactor with the chlorine feed stream. No PCE emissions from
356
this vent have been reported. »'
One major source of PCE emissions during CFC-113/CFC-114 production is
raw materia.1 storage (A in Figure 10). The PCE feedstock is generally stored
in fixed-roof tanks. ' Table 12 presents uncontrolled emission factors for
storage emissions reported by one facility. Also presented in this table are
potentially applicable control techniques and associated controlled emission
factors. The uncontrolled emission factor, 0.28 kg/Mg, was calculated from
a PCE storage emission rate of 4,400 kg/yr and an associated CFC-113
production rate of 16,000 Mg/yr (calculated as shown in Appendix A). If
emissions were controlled by a contact internal floating roof, the estimated
JES/064 60
-------
PCE emission factor would be 0.0075 kg/Mg CFC-113 produced. This estimate
is based on a controlled PCE emission rate of 660 kg/yr7 and the associated
CFC-113 production rate of 16,000 Mg/yr.1 If emissions were controlled by a
refrigerated condenser, the estimated PCE emission factor would be
0.041 kg/Mg CFC-113 produced. This emission factor was calculated from the
uncontrolled PCE emission factor and an assumed condenser control efficiency
of 85 percent.
The other major sources of PCE emissions during chlorofluorocarbon
manufacture are leaks from equipment components, such as pumps, valves,
compressors, safety relief valves, flanges, open-ended lines, and sampling
connections. Table 12 presents PCE emission rates from equipment leaks for
two CFC-113/CFC-114 production plants. Based on an equipment count provided
by each plant and SOCMI equipment leak emission factors, the uncontrolled
equipment leak emission rates were estimated using the average emission
factor method. More accurate emission estimates can be obtained by using
other methods such as the leak/no-leak or the three-strata emission factor
method. 'These methods use other data to obtain better emission estimates and
are described in Protocols for Generating Unit-Specific Emission Estimates
for Equipment Leaks of VOC and VHAP (EPA-450/3-88-010).
The control options available for equipment leaks include a monthly leak
detection and repair program, venting compressor degassing reservoirs to a
combustion device, using rupture discs on pressure relief devices, using
closed-purge sampling, and capping open-ended lines. For the two plants in
Table 12, the implementation of all these control options would reduce
equipment leak emissions overall by roughly 60 percent.7
Other potential sources of PCE emissions include loading/handling
operations and equipment openings. One chlorofluorocarbon plant reported no
emission from these sources. '7 Another plant reported annual PCE emissions
in 1983 of 0.02 Mg and 0.03 Mg from handling and equipment openings, respec-
tively. ' These emissions together represented less than one percent of the
total estimated PCE emissions from that facility. Production data were not
available to calculate emission factors for the plant.
JES/064 61
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A list of facilities producing CFC-113 and CFC-114 is presented in
Table 13. One plant producing CFC-115 and CFC-116 is also listed.
POLYVINYL CHLORIDE (PVC) PRODUCTION
Trichloroethylene is used in PVC production as a reaction chain transfer
agent to create low molecular weight polymers. The PVC suspension process is
the only process that uses TCE in this manner. Trichloroethylene is used by
about 15 percent of the companies employing the suspension process. Most of
the TCE is destroyed in the chain transfer reaction.
Process Description
The suspension process for producing PVC resins is characterized by the
formation of polymers in droplets of the liquid vinyl chloride monomer (or
other co-monomers) suspended in water. These droplets are formed by
agitation and the use of protective colloids or suspending agents.
Protective colloids are water-soluble polymers such as modified cellulose or
partially hydrolyzed polyvinyl acetate.
A flow diagram for the suspension process is shown in Figure 11. This
process is represented by the following equation:
CH2CHC1 + C2HCHOCOC3H + HgO + C2HC13 - * [-CHgCHCl rCHgCHCl :CH2CHC1-]
VCM Vinyl Acetate TCE PVC
Water, vinyl chloride monomer (VCM) and protective colloids are charged to
the polymerization reactor. Trichloroethylene is also added to the reactor
in suspension processes using TCE as a chain transfer agent. The initiator
is usually the last ingredient charged to the reactor. The initiators are
soluble in VCM and allow formation of PVC in the monomer droplets.
JES/064 63
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TABLE 13. FACILITIES PRODUCING CHLOROFLUOROCARBONS
113, 114, 115, AND/OR 116 IN 1988
Compounds Produced
Company Location CFC-113 CFC-114 CFC-115 CFC-116
Allied-Signal, Inc. Baton Rouge, LA X X
Allied Chemical
Corp.
E.I. duPont Deepwater, NJ XX
de Nemours and
Co., Inc.
Corpus Christi, TX X X
Montague, MI X
NOTE: This list is subject to change as market conditions change, facility
ownership changes, or plants are closed down. The reader should
verify the existence of particular facilities by consulting current
lists or the plants themselves. The level of emissions from any given
facility is a function of variables such as throughput and control
measures, and should be determined through direct contacts with plant
personnel. These operating plants and locations were current as of
. January 1988.
SOURCE: Reference 5.
JES/064 64
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Ingredients charged to the reactor must be carefully measured prior to
charging because a level indicator for reactors has not been developed
comrnercially. In some cases, the reactor is on a scale and the amount of
material charged is weighed in the reactor. More often, a separate weight
tank 1s-used to measure materials charged to the reactor. Reactor operators
manually charge additives that are used in small proportions.
After all materials are in the reactor, the batch is brought up to the
reaction temperature by passing steam through the reactor jackets which
allows free radical initiators to be formed. Reaction temperatures are
varied to produce a resin grade of a particular molecular weight. Once
polymerization is initiated, the reaction becomes exothermic and cooling
water must be circulated through the reactor jacket to remove the heat of
reaction.
After approximately 6 hours in the reactor, the batch temperature
and pressure drop. This signifies that nearly all the VCM has reacted
(75 percent to 90 percent of the VCM usually reacts).
Polyvinyl chloride resin, unreacted VCM (in the water, in the headspace,
and trapped in the resin) and water are the constituents remaining in the
polymerization reactor. Generally, this polymer slurry (Stream 1) is
stripped of unreacted VCM (Stream 2) using steam and vacuum. This can be
done in the reactor itself or in a separate vessel. The unreacted VCM is
purified and recycled (Stream 3), and noncondensible gases are vented.
After stripping, the batch -(Stream 4) is transferred to blend tanks
which mix the batch with other batches to insure product uniformity. The
mixed batches (Stream 5) are then fed to a continuous centrifuging operation
that separates the polymer from the water in the slurry. Both mixing tanks
and centrifuges are vented to the atmosphere if stripping is used. The
centrifuge water is recycled back to the process or discharged to the plant's
wastewater treatment system.
JES/064 66
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The wet cake (Stream 6) from centrifuging is conveyed to a rotary dryer
for further removal of the remaining (usually 25 percent) moisture.
Counter-current air temperatures in the dryer range from 65°C to 100°C.
Drying time is generally short, but large volumes of air are released.
After drying, the resin (Stream 7) may be screened to remove agglomerates.
The resin (Stream 8) is then bagged or stored in piles for bulk shipment by
trucks or rail car.
Emissions
Potential TCE emission sources during the PVC suspension process
include:12'13
o TCE unloading and storage,
o opening of equipment for cleaning and maintenance,
o pressure relief device discharges,
o process vents, such as blending tank vents, monomer recovery
system vents, and dryer exhaust vents,
o equipment leaks from valves, flanges, pumps, compressors, relief
devices, sample connections, and open-ended lines, and
o secondary sources such as wastewater.
To maintain compliance with NESHAP requirements for vinyl chloride, many of
these emission sources are controlled at PVC production plants. This has the
indirect and added benefit of controlling potential TCE emissions to some
extent. Table 14 identifies control technologies that can be applied to
reduce emissions from PVC plants.10
An estimated 130 Mg of TCE were emitted in 1978 from PVC production
processes using TCE as a reaction chain transfer agent.12 The total TCE used
in 1978 by these processes was estimated at 6,500 Mg. From these two values,
total TCE emissions per unit TCE used in PVC production are estimated at 0.02
Mg/Mg. Data are not available on the derivation of the total annual TCE
JES/064 57
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3
•4
-------
emissions estimate, nor are sufficient data available to determine the level
of control that the emissions estimate reflects.
Reference 12 presents annual emissions estimates for one facility using
TCE as a reaction chain inhibitor during the production of vinyl chloride/
vinyl acetate co-polymer. Total TCE emissions from the facility in 1983 were
estimated to be 1.1 Mg. Of this, about 55 percent were secondary emissions,
about 45 percent were equipment leaks, and about 2 percent were from TCE
storage. Equipment opening emissions and relief device discharges each
contributed less than one percent of total plant emissions. None of the
emission sources were reported to be controlled. The facility also reported
that a process vent was controlled with an incinerator and quench tank system
with a control efficiency of greater than 98 percent. However, no TCE
emissions were reported for this process vent.
The EPA does not have more recent data on emissions and control devices
at PVC production facilities using TCE as a reaction chain transfer agent.
Source Locations
Table 15 lists producers of PVC resins. Data are not available to
identify which facilities use TCE as a chain transfer agent.
JES/064 59
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TABLE 15., FACILITIES PRODUCING POLYVINYL CHLORIDE RESINS IN 1988
Company
Location
Air Products and Chemicals, Inc.
Industrial Chemicals Division
Borden Chemicals and Plastics
CertainTeed Corporation
Formosa Plastics Corporation USA
Georgia Gulf Corporation
The BF Goodrich Company
BF Goodrich Chemical Group
The Goodyear Tire & Rubber Company
Chemical Division'
Keysor-Century Corporation
Occidental Petroleum Corporation
Occidental Chemical Corporation, Subsidiary
PVC Resins and Fabricated Products
Calvert City, KY
Pensacola, PL
Geismar, LA
Illiopolis, IL
Lake Charles, LA
Delaware City, DE
Point Comfort, TX
Delaware City, DE
Plaquemine, LA
Avon Lake, OH
Deer Park, TX
Henry, IL
Louisville, KY
Pedricktown, NJ
Plaquemine, LA
Niagara Falls, NY
Saugus, CA
Addis, LA
Burlington, NJ
Burlington, NJ
Pasadena, TX
Pottstown, PA
JES/064
70
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TABLE 15. (Continued)
Company Location
SHINTECH Incorporated Freeport, TX
Union Carbide Corporation
Solvents and Coating Materials Division Texas City, TX
Vista Chemical Company Aberdeen, MS
Oklahoma City, OK
V*9en CorP- Ashtabula, OH
NOTE: This list is subject to change as market conditions change, facility
ownership changes, or plants are closed down. The reader should
verify the existence of particular facilities by consulting current
lists or the plants themselves. These operating plants and locations
were current, as of January 1988.
NOTE: Emissions only occur when TCE is used as a chain transfer agent.
Data are not available to identify which facilities use TCEl The
level of emissions from any given facility that uses TCE is a function
or variables such as throughput and control measures, and should be
determined through direct contacts with plant personnel.
SOURCE: Reference 5.
JES/064 71
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REFERENCES FOR SECTION 6
1. Mannsville Chemical Products Corp. Chemical Products Synopsis -
Fluorocarbons and Fluorocarbon Solvents. Asbury Park, New Jersey.
1984.
2. Hawley, G. G. The Condensed Chemical Dictionary, 10th ed. Van Nostra-nd.
Reinhold Company, Inc., New York, New York. 1981.
3. Pitts, D. M. Fluorocarbons (Abbreviated Report). (In) Organic
Chemical Manufacturing, Volume 8: Selected Processes.
EPA-450/3-80-028c. U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina. 1980.
4. U.S. Environmental Protection Agency. Survey of Perchloroethylene
Emission Sources. EPA-450/3-85-017. Office of Air Quality Planning-and
Standards, Research Triangle Park, North Carolina. 1985.
5. SRI International. 1988 Directory of Chemical Producers. Menlo Park,
California. 1988.
6. Letter and attachments from J. E. Cooper, Allied Corporation, to
J. R. Farmer, EPA:ESED, April 2, 1985. Response to PCE Questionnaire.
7. Memorandum from K. Fidler, and L. Kinkaid, Radian Corporation, to Carbon
Tetrachloride File, May 14, 1986. Estimates of Carbon Tetrachloride,
Chloroform, and Perchloroethylene Emissions from Chlorofluorocarbon
Production Facilities and Emission Reductions Achievable with
Additional Control.
8. Letter and attachments from J. B. Coleman, Jr., E. I. duPont de Nemours
and Company, to J. R. Farmer, EPA:ESED, January 30, 1985. Response to
PCE Letter.
9. Telecon. Barr, J., Air Products Co., with P. B. Murphy, Radian
Corporation, July 18, 1985. Information on TCE Usage in PVC
Manufacturing.
10. TRW, Inc. Vinyl Chloride - A Review of National Emission Standards.
EPA-450/3-82-003. U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina. 1982.
11. Khan, Z. S., and T. W. Hughes. Source Assessment: Polyvinyl Chloride.
EPA-600/2-78-004i. U. S. Environmental Protection Agency, Cincinnati,
Ohio. 1978.
12. U.S. Environmental Protection Agency. Survey of Trichloroethylene
Emission Sources. EPA-450/3-85-021. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. 1985.
JES/064 72
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13. Letter and attachments from R. R. Neugold, Tenneco Inc., to
J. R. Farmer, EPA:ESED, November 18, 1985. Response to TCE Letter.
JES/064 73
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JES/064
74
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SECTION 7
EMISSIONS FROM INDUSTRIES USING TRICHLOROETHYLENE
AND PERCHLOROETHYLENE AS SOLVENT
This section discusses emissions from major processes using TCE and/or
PCE as a solvent. These processes include organic solvent cleaning; dry
cleaning; paints, coatings, and adhesives manufacture and use; and aerosol
products manufacture and use. In the United States, organic solvent
cleaning (vapor) is the primary source of TCE emissions and dry cleaning is
the major source of PCE emissions.
TRICHLOROETHYLENE AND PERCHLOROETHYLENE USE IN ORGANIC SOLVENT CLEANING
Organic solvent cleaning (degreasing) is an integral part of many
industrial categories such as automobile manufacturing, electronics,
furniture manufacturing, appliance manufacturing, textiles, paper, plastics,
and glass manufacturing. Organic solvent cleaners use organic solvents to
remove water-insoluble soils (such as oils, greases, waxes, carbon deposits,
fluxes, tars, or other debris) from surfaces prior to processes such as
painting, plating, repair, inspection, assembly, heat treatment or
machining. Various solvents, including petroleum distillates, chlorinated
hydrocarbons, ketones, and alcohols, are used alone or in blends for solvent
cleaning operations.1 About 90 percent of theJCE and 15 percent of the PCE
supply in 1987 was used in solvent cleaning.2'3 Both PCE and TCE are
especially applicable to cleaning and drying metal- parts in the industries
mentioned above. :
Process Description
There are three basic types of solvent cleaning equipment: open top
vapor cleaners (OTVC), conveyorized (often called in-line) cleaners and cold
cleaners.
JES/064 75
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A typical OTVC consists of a tank equipped with a heating system and
cooling coils. Heating elements on the inside bottom of the tank boil
liquid solvent, generating the vapors needed for cleaning. Cooling coils
located on the inside perimeter of the tank above the liquid level condense
the solvent vapors, creating a controlled vapor zone which prevents vapors
from flowing out of the tank. Soiled.objects are lowered into the vapor
zone where solvent condenses on their surfaces and dissolves the soils.
Only halogenated solvents are used in the vapor phase for cleaning (or other
applications) because they have excellent cleaning properties, are
essentially nonflammable, and the heavy vapors produced can be easily
contained within the machine.
1,4
In-line cleaners feature automated conveying systems for continuous
cleaning of parts. In-line machines clean either by cold or vapor cleaning,
although most use the latter. The same basic cleaning techniques are used
for in-line cleaning as with OTVC but usually on a larger scale. Although
in-line cleaners tend to be the largest, they emit less solvent per part
cleaned than other types of cleaners because they are usually enclosed
systems, operate continuously, and feature automated parts handling. '
Cold cleaners are usually the simplest and least expensive type of
cleaner. Spraying, flushing, wiping, and immersion are often employed with
these cleaners to enhance cleaning ability. It should be noted, however,
that TCE and PCE use in cold cleaning appears to be limited. Discussions
with the major cold cleaner manufacturers indicate that TCE and PCE are not
used in cold cleaning to a significant extent. None of these manufacturers
currently sells, or has recently sold, units for use with solvents other
than methylene chloride (part of a carburetor cleaner solution) and
nonhalogenated solvents. Although there may be some older units that use
other halogenated solvents, the total number of these units nationwide is
negligible.
JES/064
76
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Emissions
Solvent evaporation occurs both directly and indirectly with all types
of solvent cleaning equipment. Major causes of emissions include loss of
solvent vapor from the tank due to diffusion and convection, and evaporation
of solvent on cleaned parts as they are withdrawn from the machine. Leaks
from the cleaner or associated equipment and losses from solvent storage and
transfer are other significant sources of emissions. The quantity of
emissions varies, depending upon the type, design, and size of equipment,
the hours of operation, operating techniques, and the type of material being
cleaned. Emissions are ultimately a function of solvent use, therefore,
techniques and practices designed to conserve solvent use are beneficial in
reducing atmospheric emissions.
Potential control methods for organic solvent cleaners include add-on
equipment and improved operating practices. Add-on equipment can be as
simple as adding covers to equipment openings, enclosing equipment,
increasing freeboard height, adding freeboard refrigeration devices, and
using automated parts handling systems. These devices limit diffusional and
convective losses from solvent tanks and evaporative losses due to solvent
carry-out. More sophisticated control techniques include carbon adsorption
systems to recover solvent vapors.
Operating practices can be improved to limit solvent emissions from
solvent cleaning. These improvements, characterized by practices that
reduce solvent exposure to the atmosphere, include: minimizing open surface
area, keeping cleaner covers closed, fully draining parts prior to removal
from cleaner, maintaining moderate conveyor speeds, keeping ventilation
rates moderate, using a coarse spray or solid stream of solvent instead of a
fine spray, not using compressed air sprays to blow-dry parts or to mix
cleaning baths, and by placing wipe rags in a closed container and reusing
them whenever possible. The emission reductions achievable through the use
of control devices vary depending on the operating schedule of the machine.
For example, an OTVC that is used constantly throughout the day will have a
JES/054 77
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greater reduction in total emissions from a control that reduces working
emissions (such as an automated parts handling system) than an OTVC that is
idle for the majority of the day.
In vapor cleaning, improper heat balance, air currents, high water
content, and solvent degradation are the primary factors that cause solvent
losses and necessitate greater virgin solvent use. Equipment configurations
and operational practices that abate the problems will be useful in reducing
potential solvent emissions from vapor cleaning. Conservation practices for
vapor cleaners as recommended by a major cleaning solvent manufacturer are
summarized below.
1. Use least amount of heat necessary to keep solvent at a boil and
provide adequate vapor production.
2. Regulate cooling level by water temperature or flow rate
adjustments.
3. Monitor water jacket temperature and flow rate to prevent
migration of hot solvent vapor up cleaner side walls.
4. Use cold coil traps to lessen vapor losses.
5. Use covers, especially during idle periods, on open-top cleaners.
6. Avoid drafts over the cleaner by locating the unit to minimize
natural drafts or use baffles to prevent vapors from being
disturbed.
7. Extend the freebound height of the cleaner.
8. Spray in the vapor zone of the cleaner to minimize the generation
of a vapor-air mixture and the disruption of the vapor interface.
9. Use minimum exhaust velocity necessary to provide proper vapor
control in the work area.
10. Arrange air movement in the room to minimize wind tunnel effects.
11. Avoid rapid parts or basket movement in the vapor zone,,
12. Minimize the level of dissolved water in the solvent.
JES/064 78
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13. Minimize the introduction of water to prevent the depletion of
solvent stabilizers.
14. Have a separate water trough for refrigerated coils.
15. Minimize corrosion and remove visible signs of it to minimize
solvent decomposition.
16. Monitor and maintain solvent stabilizers, inhibitors, and acid
acceptors.
17. Remove metal parts, fines, and sludge to prevent stabilizer
depletion and in turn solvent decomposition.
18. Avoid high oil concentration build-up.
19. Minimize solvent carry-out on parts.
20. Bring parts to vapor temperature prior to removal to minimize
dragout.
21. Do not overload the cleaning capacity of the cleaner.
22. Use properly sized baskets in the cleaner to reduce vapor-air
mixing.
23. Do not expose heating coils to solvent vapor.
24. Use only clean or non-porous materials in the cleaning process.
25. Operate a cleaner leak detection and repair program.
Tables 16 and 17 present uncontrolled emission factors, applicable
control techniques, their associated control efficiencies, and controlled
emission factors for each type of solvent cleaner.1'6 Table 16 presents
control efficiencies and controlled emission factors for solvent cleaners
that are used for a relatively small fraction of the day (Schedule A).
Table 17 presents control efficiencies, and controlled emission factors for
solvent cleaners that are used more regularly. The controlled emission
factors were derived using a material balance approach based on the
uncontrolled emission factors reported in Reference 5 and control
efficiencies reported in Reference 1. See Appendix A for an example
calculation.
JES/064 79
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EMISSION FACTORS FOR ORGAN]
S AND PERCHLOROETHyLENE 1
(CONTINUED)
S
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All the emission factors presented in Tables 16 and 17 are based on
fresh solvent input. These factors account for the recovery and reuse of
solvent contained in cleaner waste solvent streams. This recycling of waste
solvent results in a reduction in the amount of fresh solvent required for a
given cleaning application, but the percentage of fresh solvent usage that
is ultimately emitted from the cleaning process is higher.
The controlled emission factors, like the uncontrolled factors, are
expressed as kg solvent emitted per kg fresh solvent used. It is important
to note; however, that the emission controls for solvent cleaners cause both
a reduction in solvent use and a reduction in the fraction of solvent that
is emitted to the air (as illustrated in Appendix A, Section A-2). The
controlled emission factors refer only to kg solvent emitted per kg of
controlled fresh solvent used; therefore, these factors should not be
applied to estimates of uncontrolled solvent use to derive estimates of
controlled emissions.
Source Locations
Five major industry groups use TCE and PCE in degreasing operations.
These are furniture and fixtures (SIC 25), fabricated metal products
(SIC 34), electronic and electronic equipment (SIC 36), transportation
7 8
equipment (SIC 37), and miscellaneous manufacturing industries (SIC 39).'
Because of the large number of vapor degreasers, the locations of individual
facilities are not identified.
DRY CLEANING
Approximately 50 percent of the PCE consumed in the United States is
2
used as a dry cleaning solvent.
JES/064 84
-------
Process Description9'10
The principle steps in the PCE dry cleaning process are identical to
those of laundering in water, except that PCE is used instead of soap and
water. Two types of machines are used for PCE dry cleaning: transfer and
dry-to-dry. For transfer machines, clothes are washed in one unit and then
transferred to a separate unit to be dried. For dry-to-dry machines,
clothes are washed and dried in a single unit, which eliminates the clothing
transfer step.
A typical PCE dry cleaning plant is shown schematically in Figure 12.
The dry cleaning process involves the following major process steps:
charging, washing, extraction, drying, and aeration. Before the cleaning
cycle begins, small amounts of detergent and water are added to the cleaning
solvent in the charging step. The detergent and water remove water-soluble
dirts and soils from fabrics during washing, and thus, improve the cleaning
capability of the solvent.
To begin the washing step, clothes are loaded manually into the
perforated steel drum of the washer. Charged solvent is added and then
clothes and solvent are agitated by rotation of the drum. After the washing
step is complete, the drum spins at high speeds to remove the solvent through
perforations in the drum. This step is called extraction.
Next, the clothes are tumbled dry. In this step, recirculating warm air
causes most of the remaining solvent in the clothes to vaporize. The PCE-
laden drying air stream is condensed by the water condenser and recycled to
the tumbler, with no exhaust gas stream vented to the atmosphere. Recovered
solvent is returned to the pure solvent tank for recycle. After drying,
fresh ambient air is passed through the machine to freshen and deodorize the
clothes. This process is called aeration. The PCE-laden air from this step
may be vented to a control device or emitted directly to the atmosphere.
JES/064 ' 85
-------
r
Exhaust Gas/Solvent
Heated
Air
Dryer
— • — *{ Condenser r— -j
Water
To
Atmosphere
(Uncontrolled
Plant)
t
Heat
Muck
Gases
Solvent
Emissions
Oesorptlon
To
Carbon
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Plant)
Steam'
i_J_
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Adsorber
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Bottoms
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Disposal*
Separator
f
Filter
Muck
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1 Condenser
1
1
t
Disposal*
i
2
3
Currently regulated as a RCRA hazardous waste.
Figure 12. Schematic of perchloroethylene dry cleaning plant.9
JES/064
86
-------
Most machines are equipped with inductive fans that are turned on when
the washer and dryer doors are opened. During the loading and unloading of
clothes, these fans divert the PCE-laden vapors away from dry cleaning
operators and pull them through the dry cleaning machine. The gas stream is
then either vented directly out the stack or through a control device.
Efficient operation of dry cleaning plants necessitates at least partial
recovery and reuse of used solvent. There are several pieces of auxiliary
equipment used at most dry cleaning plants for recovery and purification of
PCE. These include filters that remove dirt from the PCE circulating through
the washer, and stills that purify the PCE by distillation.
As shown in Figure 12, dirty PCE from the washer is typically passed
through a filtration system. The filtration process removes most insoluble
soils, nonvolatile residue and dyes. For plants using regenerative or
tubular filters, the solids or "muck" are removed from the filters each day.
The muck contains solvent that is recovered by distillation in a muck cooker.
The recovered PCE is condensed, separated, and then returned to the solvent
storage tank. The muck solid waste is stored and then disposed of. For
plants .using cartridge filters, spent filters are generally drained and then
disposed of.
Following filtration, the solvent may either flow back to the solvent
storage tank or to the distillation unit. Distillation removes soluble oil,
fatty acids, and greases not removed by filtration. During distillation, the
PCE is vaporized and the residues are retained in the distillation bottoms.
The vaporized PCE is condensed, separated, and then returned to the solvent
storage tank. The distillation bottoms are stored prior to disposal.
Emissions
Potential sources of process emissions include losses during aeration
and emissions ducted out the stack during clothing transfer. There are no
process emissions during other parts of the dry cleaning cycle (i.e., wash
JES/064 87
-------
cycle, dry cycle) because exhaust gases are not vented to the atmosphere
during those operations. Two control techniques used by the industry for
process emissions are refrigerated condensers and carbon absorbers. Carbon
adsorbers reduce process vent emissions by about 95 percent or more,
refrigerated condensers reduce emissions by about 70 percent.
and
Fugitive emissions include PCE losses from leaky process equipment
(pumps, valves, flanges, seals, etc.), emissions of PCE from spent cartridge
filters and PCE-laden solid waste, and in-plant evaporative losses of PCE
during clothing transfer and handling. Other potential emissions include
losses from water separators, emissions from distillation units and muck
9 10
cookers, and losses from solvent retained in discarded solid wastes. ' The
control techniques used for fugitive emissions include housekeeping
procedures such as detecting, repairing, and preventing leaks, and
minimizing the exposure of PCE-laden clothes to the atmosphere. These
procedures have been detailed in References 9 and 12 and are reported to be
widely used.
Table 18 presents emission factors for transfer and dry-to-dry
machines. The factors are shown for three levels of process emission
control: uncontrolled trolled, refrigerated condenser-controlled, and carbon
adsorber-controlled. Neither the amount of solid waste generated.nor
fugitive emissions are affected by the addition of process vent controls, so
they are equal for controlled and uncontrolled machines.
Source Locations
The dry cleaning industry is composed of three sectors: commercial,
industrial, and coin-operated. Commercial plants are classified under
Standard Industrial Classification (SIC) code 7216. Industrial and
coin-operated plants are classified under SIC 7218 and SIC 7215,
respectively. Because of the large number of facilities in the United
States, no attempt has been made to identify the locations and names of
facilities.
JES/064
88
-------
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JES/064
89
-------
Commercial facilities account for 71 percent of the PCE used in dry
cleaning; industrial facilities for 11 percent; and coin-operated for
18 percent. Coin-operated facilities are usually small self-service
facilities that are associated with neighborhood laundromats. Only synthetic
.cleaning solvents (no petroleum solvents) are used at coin-operated plants
and PCE is the primary solvent used. All coin-operated plants have
dry-to-dry units where clothes are washed and dried in a single unit.
Commercial dry cleaners are typically small facilities offering non-self-
service cleaning, including small neighborhood shops, franchise shops, and
specialty cleaners. Of commercial dry cleaners, 73 percent use PCE,
24 percent use petroleum solvents, and 3 percent use trichlorotriflouro-
ethane. Host machines are transfer machines where clothes are washed in one
unit and transferred to a separate unit for drying. Industrial cleaners are
large facilities that clean items for rental services. Forty to 45 percent
of industrial cleaners have dry cleaning equipment and 50 percent of these
use PCE. A typical industrial facility has one 250 kg per load capacity
washer/extractor and three to six 38 kg capacity dryers.
PAINTS, COATINGS, AND ADHESIVES
Both TCE and PCE are used as solvents in paints, coatings, and
adhesives. In 1983, approximately 520 Mg of TCE and 1,700 Mg of PCE were
used to manufacture paints and coatings. In addition, an estimated 420 Mg of
TCE and 2,800 Mg of PCE were used to manufacture adhesives.8'13
Solvent emissions from paints, coatings, and adhesives occur through
evaporation upon application. Therefore, it is estimated that all TCE and
PCE used in these applications is eventually emitted to the atmosphere.7'8
No data were found on the emissions of TCE or PCE during the manufacture
of paints, coatings, and adhesives. The Standard Industrial Classification
(SIC) code for paint and allied product manufacturing is 285; the SIC code
for adhesives and sealants manufacturing is 2891.
JES/064 90
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AEROSOLS
Perch!oroethylene is used as a solvent and carrier in aerosol products
such as spray paints and cleaners.14'15 Facilities packaging aerosols
consumed about 2,630 Mg of PCE in 1985.16 Some aerosol products contain
TCE, but insufficient data exist to quantify the extent of TCE use.
Overall, TCE use in these products is believed to be negligible.16
Therefore, this section discusses only PCE emissions during aerosol
packaging and use.
The total PCE emitted in 1985 from five packaging facilities using PCE
was about 5.4 Mg.15 The total PCE consumed by these facilities was about
1,470 Mg. From these two values, the uncontrolled emission factor for
aerosol packaging is estimated to be 3.7 kg/Mg consumed. Of the
uncontrolled emissions, approximately 81 percent were from handling
(primarily mixing tank) operations, 17 percent were from equipment leaks,
and 2 percent were from storage tanks.15 Other potential sources include
wastewater emissions and accidental releases.
During use of aerosol products, PCE is released by evaporation after
application (or by direct release in the gaseous phase). Consequently, it is
assumed that 100 percent of PCE used in aerosol applications is emitted to
the atmosphere.
JES/064 • 91
-------
REFERENCES FOR SECTION 7
1. U.S. Environmental Protection Agency. Alternative Control Technology
Document - Halogenated Solvent Cleaners. EPA-450/3-89-030. Office of Air
Quality Planning and Standards, Research Triangle Park, North Carolina.
August 1989.
2. Mannsville Chemical Products Corp. Chemical Products Synopsis -
Perch!oroethylene. Asbury Park, New Jersey. 1987.
3. Mannsville Chemical Products Corp. Chemical Products Synopsis -
Trichloroethylene. Asbury Park, New Jersey. 1987.
4. 6CA Corporation. Organic Solvent Cleaners - Background Information for
Proposed Standards. EPA-450/2-78-045a. U.S. Environmental Protection
Agency, Research Triangle Park, North Carolina. 1979.
•5. Dow Chemical Company. Waste Minimization for Chlorinated Solvent Users.
Chemicals and Metals Department, Midland, Michigan. June 1988.
6. Memorandum from R. C. Mead, Radian Corporation, to D. A. Beck, U.S.
Environmental Protection Agency, September 3, 1987. Documentation of
Emissions and Long-term Exposure Model Inputs for the Organic Solvent
Cleaning Source Category.
7. U.S. Environmental Protection Agency. Survey of Perch!oroethylene
Emission Sources. EPA-450/3-85-017. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. 1985.
8. U.S. Environmental Protection Agency. Survey of Trichloroethylene
Emission Sources. EPA-450/3-85-021. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. 1985.
9. U.S. Environmental Protection Agency. Perchloroethylene Dry Cleaners -
Background Information for Proposed Standards. EPA-450/3-79-029a.
Emission Standards and Engineering Division, Research Triangle Park,
North Carolina. 1980.
10. Memorandum from R. L. Ajax and 8. R. Wyatt, U.S. Environmental
Protection Agency, to J. R. Farmer, U.S. Environmental Protection
Agency, August 27, 1986. Information Memorandum - Emissions of
Perchloroethylene from Dry Cleaning Operations. Attachment A.
11. Memorandum from E. C. Moretti, Radian Corporation, to Perchloroethylene
Dry Cleaning Project File, March 25, 1988. Documentation of Emission
Factors for the Perchloroethylene Dry Cleaning Industry.
12. U.S. Environmental Protection Agency. Control of Volatile Organic
Emissions from Perchloroethylene Dry Cleaning Systems.
EPA-450/2-78-050. Office of Air Quality Planning and Standards,
Research Triangle Park, North Carolina. 1978.
JES/064
92
-------
13. Letter from D. L. Morgan, Cleary, Gottlieb, Steen, and Hamilton, to
5;™ « osenstee1' U'S' Environmental Protection Agency, March 1, 1985
HSIA Data on Perch!oroethylene Production and Consumption.
14. Maklan, D. M D. H. Steele, S. K. Dietz, G. L. Brown, and S. Fallah.
Household Products Containing Methylene Chloride and Other Chlorinated
Solvents: "A Shelf Survey." EPA-OTS 560/5-87-006. U.S. Environmental
Protection Agency, Washington, D.C. 1987.
15. Memorandum from J. Martinez, R. Wassel, and G. Bockol, Radian
Corporation, to File of Aerosol Manufacturing - Packagers, Formulators,
and Users Work Assignment, October 13, 1987. Emission Estimates and
Controls Memorandum for Emissions from those Aerosol Packaging
Facilities Responding to Section 114 Questionnaires.
16. Memorandum from E. C. Moretti, Radian Corporation, to Aerosol Packaqers
Project File, January 19, 1988. Documentation of Baseline and
Controlled Emission Parameters for Aerosol Packagers.
JES/064 93
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JES/064
94
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SECTION 8
OTHER POTENTIAL SOURCES OF TRICHLOROETHYLENE
AND PERCHLOROETHYLENE EMISSIONS
This section summarizes information on other potential sources of TCE
and PCE emissions. These sources include (1) distribution facilities,
(2) publicly owned treatment works (POTW), and (3) unidentified or
miscellaneous uses.
DISTRIBUTION FACILITIES1'2
Roughly 70 percent of PCE and nearly all TCE produced is so-ld through
chemical distributors. There are an estimated 300 chemical distributors
handling chlorinated solvents. Table 19 presents the five largest TCE
distributors and the three largest PCE distributors. Data are not available
to identify all distribution facilities handling these solvents.
In general, distributors maintain as few as three to as many as
65 regional distribution facilities spread out across the nation. Each
regional distributor receives chemicals directly from the producer by tank
truck or railcar. Transportation is provided by the distributor. The
received chemicals are stored by regional distributors in 8,000 to
20,000 gallon fixed-roof storage tanks. The storage tanks used by the
regional distributor include vertical, horizontal, and underground tanks.
Turnover times for storage tanks typically range from two weeks to a little
over a month. Although the exact number of distributors and distribution
facilities that handle TCE is not known, it is estimated that there are
96 TCE storage tanks and 270 PCE storage tanks owned by distributors.
Emissions from distribution facilities can be categorized as two types:
storage and handling. Storage emissions include breathing and working losses
from tanks. Handling emissions result from vapor displacement when drums and
tanks are filled.
JES/064 95 -,
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TABLE 19. SUMMARY OF MAJOR TRICHLOROETHYLENE AND
PERCHLOROETHYLENE DISTRIBUTORS
Company
Ashland
McKesson
Chera-Central
Detrex
Thompson -Hayward
Number of
Storage
Facilities
61
63
31
25
26
Number of TCE
Storage
.Tanks
52
6
15
10
6
Number of PCE
Storage
Tanks
37
6
10
--
--
SOURCE: References 1 and 2.
JES/064
96
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In References 1 and 2, storage and handling emissions from distribution
facilities were estimated using AP-42 emission factors and data supplied by
major distributors. An estimated 21 Mg of TCE and 27 Mg of PCE were emitted
by uncontrolled storage tanks at distribution facilities nationwide in 1983.
Approximately 65,700 Mg of TCE and 162,000 Mg of PCE were sold through
distributors in 1983. From these values, uncontrolled storage emission
factors are calculated to be 0.3 kg/Mg and 0.2 kg/Mg for TCE and PCE,
respectively.
Total handling emissions at distribution facilities in 1983 were
estimated at 18 Mg/yr for TCE and 23 Mg/yr for PCE. Using the TCE and PCE
distribution estimates above, the uncontrolled emission factors for handling
operations are calculated to be 0.3 kg/Mg and 0.1 kg/Mg for TCE and PCE,
respectively.
PUBLICLY OWNED TREATMENT WORKS (POTWs)
Trichloroethylene and PCE may be emitted from publicly owned treatment
works, depending on the type of waste streams received. The primary source
of these emissions is believed to be industrial discharges containing TCE and
PCE. A recent study used emissions modeling to estimate compound-specific
emission factors for a hypothetical average POTW that treats industrial
wastewater. Atmospheric emissions of TCE from the hypothetical POTW were
estimated to be 62 percent of the TCE in the POTW influent; atmospheric
emissions of PCE were estimated to be 70 percent of the influent PCE.
Characteristics of the hypothetical POTW were based on data obtained in
a previous study of 1,600 POTWs nationwide identified as treating industrial
discharges. The hypothetical POTW included the four most common major unit
operations identified in the database of 1,600 industrial POTWs: 1} aerated
grit chamber, 2) primary clarifier, 3) mechanically aerated basin, and
4) chlorine contact chamber. The average flowrate of the 1,600 POTWs was
0.5906 cubic meters per second, so this was the flowrate selected for the
hypothetical POTW.
JES/064 97
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UNIDENTIFIED OR MISCELLANEOUS SOURCES OF TRICHLOROETHYLENE AND
PERCHLOROETHYLENE
Trichloroethylene and PCE are used in miscellaneous chemical synthesis
and solvent applications. For example, TCE is used as a reactant to produce
pesticide intermediates. An estimated 3,670 Mg of TCE were consumed for this
purpose by the pesticide industry in 1984. Trichloroethylene may also be
used in the chemical synthesis of f1ame-retardant chemicals; as a solvent in
pharmaceutical manufacture; as a solvent in waterless preparation, dying, and
finishing operations in the textile industry; and as a carrier solvent in
formulated consumer products such as insecticides, fungicides, typewriter
5-8
correction fluids, paint removers, and paint strippers.
The known miscellaneous uses of PCE primarily include solvent
applications. The pharmaceutical industry consumed about 7 Mg of PCE solvent
in 1985. In textile processing, PCE functions as a scouring solvent,
removing oils from fabrics after knitting and weaving operations, and as a
carrier solvent for fabric finishes and water repellants, and for sizing and
q
desizing. Perch!oroethylene is miscible with other common solvents and is
an ingredient in blended solvents. Perchloroethylene is used as a carrier
solvent in many products such as printing inks, cleaners, polishes,
6 9
lubricants, and silicones. ' It is also used as a recyclable dielectric
fluid for power transformers, heat transfer medium, and pesticide
intermediate.
No specific emission factors were found for TCE and PCE emissions from
these miscellaneous uses of TCE and -PCE. National emissions of these
compounds from pesticide and pharmaceutical manufacture have been reported to
be negligible. * It is assumed that all TCE and PCE used in consumer
products is eventually emitted to the atmosphere.
Both TCE and PCE may also be emitted during solid and hazardous waste
treatment, storage and disposal. Emissions of TCE and PCE have been reported
from hospital waste incineration, waste oil combustion, sewage sludge
JES/064
98
-------
incineration, and landfills.10'13 The quantity of emissions depends on
waste type and disposal techniques. The reader is encouraged to investigate
specific sites to determine the potential for TCE or PCE emissions from
these sources.
JES/064 gg
-------
REFERENCES FOR SECTION 8
1. U.S. Environmental Protection Agency. Survey of Perch!oroethylene
Emission Sources. EPA-450/3-85-017. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. 1985.
2. U.S. Environmental Protection Agency. Survey of Trichloroethylene
Emission Sources. EPA-450/3-85-021. Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina. 1985.
3. White, T. S., Radian Corporation. Volatile Organic Compounds Emissions
from Hazardous Waste Treatment Facilities at Downstream POTW (Final
Report). Prepared under EPA Contract No. 68-02-4378. U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina. 1987.
4. Memorandum from R. Pandullo, and R. Nash, Radian Corporation, to
Methylene Chloride File, July 24, 1986. Estimates of Hazardous Compound
Emissions from Pesticide Facilities and Emission Reductions Achievable
with Additional Controls.
5. Mannsville Chemical Products Corp. Chemical Products Synopsis -
Trichloroethylene. Asbury Park, New Jersey. 1987.
6. Maklan, D. M., D. H. Steele, S. K. Dietz, 6. L. Brown, and S. Fallah.
Household Products Containing Methylene Chloride and Other Chlorinated
Solvents: "A Shelf Survey." EPA-OTS 560/5-87-006. U.S. Environmental
Protection Agency, Washington, D.C. 1987.
7. Memorandum from R. Pandullo, R. Nash, and P. Murphy, Radian Corporation,
to Methylene Chloride File, September 17, 1986. Estimates of
Potentially Hazardous Compound Emissions from Pharmaceutical Facilities
and Emission Reductions Achievable with Additional Controls.
8. McNeil!, W. C., Jr. Trichloroethylene. (In) Encyclopedia of Chemical
Technology, 3rd ed., Volume 5. R. E. Kirk, D. F. Othmer, M. Grayson,
and D. Eckroth, eds. John Wiley and -Sons, New York, New York. 1978.
pp. 745-753.
9. Mannsville Chemical Products Corp. Chemical Products Synopsis -
Perch!oroethylene. Asbury Park, New Jersey. 1987.
10. Pope, A. A., P. A. Cruse; and C. C. Most. Toxic Air Pollutant Emission
Factors -• A Compilation for Selected Air Toxic Compounds and Sources.
EPA-450/2-88-006a. U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina. 1988.
11. Harkov, R., S. J. Gianti, J. W. Bozzeli, and J. E. LaRegina. Monitoring
Volatile Organic Compounds at Hazardous and Sanitary Landfills in New
Jersey. Journal of Environmental Science and Health. A20(5):491-501.
1985.
JES/064
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12. Wood, J. A., and M. L. Porter. Hazardous Pollutants in Class II
Landfills. Journal of the Air Pollution Control Association.
37(5):609-615. 1987.
13. Fennelly, P. F., M. McCabe, J. M. Hall, M. F. Kozik, M. P. Hoyt,
G. T. Hunt, GCA Corporation. Environmental Characterization of
Disposal of Waste Oils by Combustion in Small Commercial Boilers.
EPA-600/2-84-150. U.S. Environmental Protection Agency, Cincinnati,
Ohio. 1984.
JES/064
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SECTION 9
SOURCE TEST PROCEDURES
Trichloroethylene and perch!oroethylene emissions can be measured using
EPA Reference Method 18, which was added in the Federal Register on
October 18, 1983. This method applies to the analysis of approximately
90 percent of the total gaseous organics emitted from industrial sources.1
In Method 18, a sample of the exhaust gas to be analyzed is drawn into
a Tedlar® or alumized Mylar® bag as shown in Figure 13. The bag is placed
inside a rigid leak proof container and evacuated. The bag is then
connected by a Teflon* sampling line to a sample probe (stainless steel,
Pyrex® glass, or Teflon®) at the center of the stack. Sample is drawn into
the bag by pumping air out of the rigid container.
The sample is then analyzed by gas chromatography (GC) coupled with
flame ionization detection (FID). Analysis should be conducted within seven
days of sample collection. The GC operator should select the column and GC
conditions that provide good resolution and minimum analysis time for the
compounds of interest. One recommended column is 3.05 m by 3.2 mm stainless
steel, filled with 20 percent SP-2100/0.1 percent Carbowax 1500 on 100/120
Supelcoport®.1 Zero helium or nitrogen should be used as the carrier gas at
a flow rate that optimizes good resolution.
The peak areas corresponding to the retention times of
trichloroethylene and perchloroethylene are measured and compared to peak
areas for a set of standard gas mixtures to determine the trichloroethylene
and perchloroethylene concentrations. The detection range of this method is
from about 1 ppm to the upper limit governed by GC detector (FID) saturation
or column overloading; however, the upper limit can be extended by diluting
the stack gases with an inert gas or by using smaller gas sampling loops.
JES/064 103
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REFERENCES FOR SECTION 9
1. Method 18: Measurement of Gaseous Organic Compound Emissions by Gas
Chromatography. Federal Register 48(202}:4834A-4a3fii 1933.
JES/064 105
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JES/064
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APPENDIX A
DERIVATION OF EMISSION FACTORS
JES/064 A_!
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JES/064 A-2
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APPENDIX A
DERIVATION OF EMISSION FACTORS
A-l. DERIVATION OF CFC-113 PRODUCTION RATE AT ALLIED CHEMICAL FACILITY
(1) - U.S. sales of CFC-113 and CFC-11 = 125 x 106 Ibs in 19831
CFC-113 is estimated to account for 95 percent of the sales1
DuPont supplies about 70 percent of the CFC solvent market, with
Allied Chemical selling the remaining 30 percent1
Allied Chemical has only one facility that produces CFC-113
(2) - Calculate CFC-113 production in 1983 at the Allied Chemical,
Baton Rouge, Louisiana, plant as follows:
6 Mg
(125 x 10° Ibs) (0.95) (0.30) ( -) = 16,000 Mg CFC-113
2205 Ib
A-2. EXAMPLE CALCULATION: RELATIVE SOLVENT USAGE AND EMISSION FACTORS
FOR CONTROLLED VS. UNCONTROLLED CLEANERS
o The controlled and uncontrolled emission factors are related as
fol1ows:
(Equation
where,
ec s controlled emission factor (kg emitted per kg fresh solvent
feed)
eu = uncontrolled emission factor (kg emitted per kg fresh solvent
feed)
n = efficiency of control device
JES/064 A_3
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The relative amount of fresh solvent used by a controlled cleaner
relative to the amount used by an uncontrolled cleaner is:
Lli
1 - e.
relative solvent usage factor
(Equation 2)
Example Case: Open Top Vapor Degreaser (OTVD)
Consider a situation where a cleaning job requires 1 kg/hr of fresh
solvent in the uncontrolled situation. The uncontrolled emission
factor (with recycle) for OTVD using PCE is 0.93 kg emitted per kg
fresh solvent used.
Emissions 0.93 kg/hr solvent
t
Fresh Solvent
1.0 kg/hr
Degreaser
Unrecoverable waste 0.07 kg/hr solvent
Now assume controls are applied (refrigerated freeboard chiller) at a
control efficiency of 40 percent. Emissions are reduced by 40 percent
but the amount of unrecoverable waste solvent does not change.
Emissions 0.93 x (1 - .40) = 0.56 kg/hr solvent
t
Fresh Solvent
? kg/hr
Degreaser
Unrecoverable waste 0.07 kg/hr solvent
New solvent usage = 0.56 + 0.07 = 0.63 kg/hr
New emission factor (ec), fresh solvent basis = 0.56/0.63 =0.89 kg/kg
Relative solvent usage, controlled vs. uncontrolled (r) - 0.63/1.0 - 0.63
JES/064
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Check Equations 1 and 2:
0.93 (1 - .40)
ec s T; I " = °-89 kg/kg, which checks with the example
(1 - 0.93 x 0.40) calculation
1 - 0.93
r „ = o.63, which checks with the example calculation
1 - 0.89
A-3. DERIVATION OF EQUIPMENT LEAK EMISSION FACTORS AS A FUNCTION OF
PRODUCTION CAPACITY FOR SELECTED PRODUCTION PROCESSES
The fugitive emission rate is generally independent of plant capacity.
Therefore, Sections 4, 5, and 6 of. this document present equipment leak
emissions as a function of time (Mg/yr) rather than capacity (kg/Mg). In
some cases, however, the reader may find it necessary to use equipment leak
emission factors expressed as a function of capacity. These can be
calculated based on the estimated annual emission rate and the estimated
total production capacity. Table A-l presents TCE and PCE emission factors
(in kg/Mg) for TCE, PCE, and CFC-113 production processes. A sample
calculation is shown below for TCE production by ethylene dichloride
chlorination:
Estimated TCE production capacity at one plant in 1983: 54,000 Mg/yr4
Estimated TCE equipment leak emissions from plant in 1983 (control status
is considered confidential) =24.1 Mg/yr
Calculate equipment leak emission factor as follows:
(24.1 Mg/yr) (1000 kg/Mg) = 0.45 kg TCE emitted/Mg TCE production capacity
(54,000 Mg/yr)
JES/064 A_5
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REFERENCES FOR APPENDIX A ;
1. Mannsville Chemical Products Corp. Chemical Products Synopsis -
Fluorocarbon Solvents. Cortland, New York. 1984.
2. U.S. Environmental Protection Agency. Survey of Perchloroethylene
Emission Sources. EPA-450/3-85-017. Office of Air Quality Planning
and Standards, Research Triangle Park, North Carolina. 1985.
3. U.S. Environmental Protection Agency. Survey of Trichloroethylene
Emission Sources. EPA-450/3-85-021. Office of Air Quality Planning
and Standards, Research Triangle Park, North Carolina. 1985.
4. SRI International. 1983 Directory of Chemical Producers. Menlo Park,
California. 1983.
5. Memorandum from K. Fidler and L. Kinkaid, Radian Corporation, to Carbon
Tetrachlpride File, May 14, 1986. Estimates of Carbon Tetrachloride,
Chloroform, and Perchloroethylene Emissions from Chlorofluorocarbon
Production Facilities and Emission Reductions Achievable with
Additional Control.
JES/064 . A-7
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
IO.
EPA-450/2-89-013
3. RECIPIENT'S ACCESSION NO.
I. TITLE AND SUBTITLE
Locating And Estimating Air Emissions From
Sources of Perchloroethylene And Trichloroethylene
S. REPORT DATE
August 1989
i. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Claire C. Most
8. PERFORMING ORGANIZATION REPORT NO.
I. PERFORMING ORGANIZATION NAME AND AOOHESS
Radian Corporation
Post Office Box 13000
Research Triangle Park, NC 27709
1O. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-02-4392
12. SPONSORING AGENCY NAME AND ADDRESS
Air Quality Management Division
•OAR, OAQPS-,''AQMD-, PCS (MD-15) '
Noncriteria Pollutant Programs Branch (MD-15)
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Final
t«. SPONSORING AGENCY'CODE
5. SUPPLEMENTARY NOTES
EPA Project Officer: Anne A. Pope
various potentially
as this to compile
To assist groups interested in inventorying air emissions of
toxic substances, EPA is. preparing a series of documents such
available information on sources and emissions of these substances. This document
deals specifically with perchloroethylene and trichloroethylene. Its intended
audience includes Federal, State, and local air pollution personnel and others in
locating potential emitters of perchloroethylene and trichloroethylene and in
making gross estimates of air emissions therefrom.
This document presents information on (1) the types of sources that may emit
perchloroethylene and trichloroethylene, (2) process variations and release points
that may be expected within these sources and (3) available emissions information
indicating the potential for trichloroethylene and perchloroethylene releases into
the air from each operation.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
Perchloroethylene
Trichloroethylene
Air Emission Sources
Locating Air Emission Sources
Toxic Substances
8. DISTRIBUTION STATEMENT
Unlimited
19. SECURITY CLASS (This Report I
Unclassified
21. NO. OF PAGES
124
20. SECURITY CLASS (Tin'spage/
Unclassified
22. PRICE •
EPA Form 2220-1 (R«v. 4-77) ' PREVIOUS EDITION is OBSOLETE
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