[Note: with the publication of the Fifth Edition of AP-42, the Chapter and Section number for
Chlor-Alkali changed to 8.11.]
BACKGROUND REPORT
AP-42 SECTION 5.5
CHLOR-ALKALI INDUSTRY
Prepared for
U.S. Environmental Protection Agency
OAQPS/TSD/EIB
Research Triangle Park, NC 27711
December 4,1992
Pacific Environmental Services, Inc.
P.O. Box 12077
Research Triangle Park, NC 27709
919/941-0333

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This report has been reviewed by the Technical Support Division of the Office of Air Quality
Planning and Standards, EPA. Mention of trade names or commercial products is not intended to
constitute endorsement or recommendation for use. Copies of this report are available through
the Library Services Office (MD-35), U.S. Environmental Protection Agency, Research Triangle
Park, NC 27711.
1

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TABLE OF CONTENTS
1.0 INTRODUCTION	 1
2.0 INDUSTRY DESCRIPTION 		2
2.1	GENERAL		2
2.2	PROCESS DESCRIPTION		2
2.3	EMISSIONS AND CONTROLS		6
2.4	REVIEW OF SPECIFIC DATA SETS		6
2.5	REFERENCES FOR CHAPTER 2		9
3.0 GENERAL EMISSION DATA REVIEW AND ANALYSIS PROCEDURES		10
3 .1 LITERATURE SEARCH AND SCREENING		10
3.2	EMISSION DATA QUALITY RATING SYSTEM		11
3.3	EMISSION FACTOR QUALITY RATING SYSTEM		12
3 .4 REFERENCES FOR CHAPTER 3 		14
4.0 POLLUTANT EMISSION FACTOR DEVELOPMENT		15
4.1	REVIEW OF SPECIFIC DATA SETS		15
4.2	CRITERIA POLLUTANT EMISSIONS DATA		17
4.3	NONCRITERIA POLLUTANT EMISSIONS DATA 		18
4.4	DATA GAP ANALYSIS		34
4.5	REFERENCES FOR CHAPTER 4		36
APPENDIX A. AP-42 SECTION 5.5 	 37
ii

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LIST OF TABLES
TABLE 4.3-1 (METRIC UNITS)
HAZARDOUS AIR POLLUTANTS: MERCURY EMISSIONS	 19
TABLE 4.3-1 (ENGLISH UNITS)
HAZARDOUS AIR POLLUTANTS: MERCURY EMISSIONS	 21
TABLE 4.3-2 (METRIC UNITS)
HAZARDOUS AIR POLLUTANTS: CHLORINE EMISSIONS 	 24
TABLE 4.3-2 (ENGLISH UNITS)
HAZARDOUS AIR POLLUTANTS: CHLORINE EMISSIONS 	 28
TABLE 4.3-3 (METRIC UNITS)
GLOBAL WARMING GASES: CARBON DIOXIDE	 33
TABLE 4.3-3 (ENGLISH UNITS)
GLOBAL WARMING GASES: CARBON DIOXIDE	 33
TABLE 4.5-1 :LIST OF CONVERSION FACTORS 	 35
LIST OF FIGURES
Figure 2.2-1 	 4
Figure 2.2-2 	 5
in

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1.0	INTRODUCTION
The document "Compilation of Air Pollutant Emission Factors" (AP-42) has been
published by the U.S. Environmental Protection Agency (the EPA) since 1972. Supplements to
AP-42 have been routinely published to add new emission source categories and to update
existing emission factors. AP-42 is routinely updated by the EPA to respond to new emission
factor needs of the EPA, state, and local air pollution control programs and industry.
An emission factor relates the quantity (weight) of pollutants emitted to a unit of activity
of the source. The uses for the emission factors reported in AP-42 include:
1.	Estimates of area-wide emissions;
2.	Emission estimates for a specific facility; and
3.	Evaluation of emissions relative to ambient air quality.
The purpose of this report is to provide background information from process information
obtained from industry comment and test reports to support revision of emission factors for
chlor-alkali production.
Including the introduction (Chapter 1) this report contains four chapters. Chapter 2 gives a
description of the chlor-alkali industry. It includes a characterization of the industry, an overview
of the different process types, a description of emissions, and a description of the technology
used to control emissions resulting from chlor-alkali production.
Chapter 3 is a review of emissions data collection and analysis procedures. It describes the
literature search, the screening of emission data reports, and the quality rating system for both
emission data and emission factors. Chapter 4 details criteria and noncriteria pollutant emission
factor development. It includes the review of specific data sets and the results of data analysis.
Particle size determination and particle size data analysis methodology are described when
applicable. Appendix A presents AP-42 Section 5.5.
1

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2.0	INDUSTRY DESCRIPTION
2.1	GENERAL12
The chlor-alkali electrolysis process results in the manufacture of chlorine, hydrogen and
sodium hydroxide (caustic) solution. Of these three, the primary product is chlorine.
Chlorine is one of the more abundant chemicals produced by industry and has a wide variety of
industrial uses. Chlorine was first used to produce bleaching agents for the textile and paper
industries and for general cleaning and disinfecting. Since 1950, chlorine has become
increasingly important as a raw material for synthetic organic chemistry. Chlorine is an essential
component of a multitude of end products including materials of construction, solvents, and
insecticides, to name a few.
In 1991, 52 chlor-alkali plants were in operation in 23 states around the country. Louisiana
and Texas have the largest number of plants operating within their borders (9 and 6,
respectively). Annual production from facilities in the U.S. was 9.9 million megagrams (10.9
million tons) in 1990 after peaking at 10.4 million megagrams (11.4 million tons) in 1989.
2.2	PROCESS DESCRIPTION13
The three basic processes for the electrolytic production of chlorine are 1) the diaphragm
cell process (Griesheim cell, 1885), 2) the mercury cell process (Castner-Kellner cell, 1892), and
3) the membrane cell process (1970). In each process, a salt solution is electrolyzed by the action
of direct electric current which converts chloride ions to elemental chlorine.
The overall process reaction is:
2NaCl + 2H20 - Cl2 II, 2NaOH	(1)
Each process represents a different method of keeping the chlorine (Cl2) produced at the positive
electrode (anode) separate from the caustic soda (NaOH) and hydrogen (H2) produced, directly
or indirectly, at the negative electrode (cathode). Of the chlorine produced in the U.S. in 1989, 94
percent was produced either by the diaphragm cell or mercury cell process. Therefore, these will
be the only two processes discussed in detail.
2

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Diaphragm Cell Process
Figure 2.2-1 shows a simplified block diagram for the diaphragm cell process.Water and
sodium chloride salt are first combined to create the starting brine solution. The brine next
undergoes precipitation and filtration steps to remove any impurities. After the addition of heat
and more salt, the nearly saturated, purified brine is heated again before entering the electrolysis
portion of the process where direct electric current is applied. The anode area is separated from
the cathode by a permeable asbestos-based diaphragm
to prevent the reaction of caustic soda with chlorine. The chlorine produced at the anode is
removed as the saturated brine flows through the diaphragm to the cathode chamber. The
chlorine, which contains oxygen, is purified by liquefaction and evaporation to yield a dry,
liquified product.
The caustic brine produced at the cathode is freed from salt and concentrated in an
elaborate evaporative process to produce commercial caustic soda. The salt separated from the
caustic brine is recycled to saturate the dilute brine. The hydrogen removed in the cathode
chamber is cooled and purified by removal of oxygen, then used in other plant processes or sold.
Mercury Cell Process
Figure 2.2-2 shows a simplified block diagram for the mercury cell process. The recycled brine
from the electrolysis process (anolyte) first is dechlorinated and then purified by a
straightforward precipitation-filtration process. The brine and liquid mercury (which is used as
the cathode) enter the cell flowing concurrently. The electrolysis process creates chlorine at the
anode and elemental sodium at the cathode. The chlorine is taken off to be cooled, dried, and
compressed for sales. The sodium combines with mercury to form sodium amalgam. The
amalgam is further reacted with water in a separate reactor called the decomposer to produce
hydrogen gas and caustic soda solution. The caustic and hydrogen are then separately cooled and
the mercury removed before proceeding to storage, sales or other processes.
3

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SALT
WATER (BRINE)
SALT
PRECI PIT/ANTS
PURIFIED BRINE
CHLORINE GAS
SALT
HYDROGEN
HYDROGEN
SALT
COOUNG
COMPRESSION
HEAT
EXCHANGE
ELECTROLYSIS
BRINE
SATURATION
BRINE
SATURATION
l-EAT
EXCHANGE
CONCBSfTRATlON
PRECIPITATION
SODIUM HYDROXIDE	HYDROGEN	CHLORINE
Figure 2.2-1. Simplified diagram of the diaphragm cell process
4

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~LUTHDBRISE
l-MDROCI-LORC
hMDROQ-LCRCACID
CH-ORISEG^S
DKK.OR NATION
EHHRlYaS
PRECIPITATION
COOLING
PMPLGPM
DBoavposmoN
COOLING
COOLING
COOLING
SODUMI-MDROXIDE	l-MDRDGBM	CI-LORISE
Figure 2.2-2. Simplified diagram of the mercury cell process
5

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2.3	EMISSIONS AND CONTROLS4
Emissions from mercury and diaphragm cell plants include chlorine gas, carbon dioxide,
carbon monoxide, and hydrogen. Gaseous chlorine is present in the blow gas from liquefaction,
from vents in tank cars and tank containers during loading and unloading, and from storage tanks
and process transfer tanks. Carbon dioxide emissions result from the decomposition of
carbonates in the brine feed when contacted with acid. Carbon monoxide and hydrogen are
created by side reactions within the production cell. Other emissions include mercury vapor from
mercury cathode cells and chlorine from compressor seals, header seals, and the air blowing of
depleted brine in mercury-cell plants. Emissions from these locations are, for the most part,
controlled through the use of the gas in other parts of the plant, neutralization in alkaline
scrubbers, or recovery of the chlorine from effluent gas streams.
2.4	REVIEW OF SPECIFIC DATA SETS
Pacific Environmental Services (PES) contacted the following sources to obtain the most
up-to-date information on process descriptions and emissions for this industry:
1)	Alabama Department of Environmental Management, Montgomery, AL.
2)	Dow Chemical Corporation, Freeport, TX.
3)	Elf-Atochem North America Inc., Portland, OR, and Tacoma, WA.
4)	Florida Department of Environmental Regulation, Tallahassee, FL.
5)	Georgia Department of Natural Resources, Atlanta, GA.
6)	Kansas Department of Health and Environment, Topeka, KS.
Michigan Department of Natural Resources, Lansing, MI.
Missouri Department of Natural Resources, Jefferson City, MO.
North Carolina Division of Environmental Management, Raleigh, NC.
10)	Pennsylvania Department of Environmental Resources, Harrisburg, PA.
11)	PPG Industries, Pittsburgh, PA, and New Martinsville, WV.
12)	The Chlorine Institute, Washington, DC.
Responses were received from Sources (1), (3), (11) and (12). No responses were received
from the remaining sources.
Source (1) provided a source test for mercury emissions that could not be used to update
emission factors (See Section 4.1, Reference 2, for details). Sources (3) and (11) provided
6

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general process description information that was useful in confirming industry process
descriptions. Source (12) provided a significant amount of both statistical data (production
volumes, number of facilities, facility locations) and process description information. PES
incorporated the information from these four sources into the AP-42 chapter revision.
PES also travelled to Texas Air Control Board regional offices in Houston and Beaumont,
Texas to obtain copies of any compliance test data or reports for chlor-alkali plants. Although a
number of facilities are located in this part of the country, no data was available at either
location. Although other States, such as Louisiana, may have valid chlor-alkali source tests, the
States would not voluntarily review their files and provide PES with copies of the tests. Travel
to each State to obtain the information was beyond the project scope of work.
Pacific Environmental Services obtained information from References 1 through 3 through
a literature search of the chlor-alkali industry. Reference 4 was obtained from the AP-42
Background File. Each reference was used to update Section 5.5 as discussed below.
Reference 1: Ullmann's Encyclopedia ofIndustrial Chemistry
Process diagrams and descriptions were updated utilizing Reference 1, which was obtained
from a literature search.
Reference 2: Pamphlets provided by The Chlorine Institute
Reference 2 was obtained from Source (12) above. Data from this reference was used to
update production volumes and define facility count and regional facility distribution.
Reference 3: 1991 Directory of Chemical Producers: United States of America
Reference 3 was obtained from a literature search and used to confirm the statistical data
obtained from Reference 2.
7

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Reference 4: Atmosvheric Emissions from Chlor-Alkali Manufacture.
Reference 4 was used to develop chlor-alkali emission factors as was done in the
April 1981 Section 5.5 revision.
8

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2.5	REFERENCES FOR CHAPTER 2
1.	Ullmann's Encyclopedia of Industrial Chemistry. Volume A, VCH Publishers, New York,
1989.
2.	Pamphlets provided by Arthur E. Dungan of The Chlorine Institute, Inc., Washington,
D.C. January 1991.
3.	1991 Directory of Chemical Producers: United States of America. Menlo Park, California:
Chemical Information Services, Stanford Research Institute, 1991.
4.	Atmospheric Emissions from Chlor-Alkali Manufacture. U.S. EPA, Air Pollution Control
Office. Research Triangle Park, N.C. Publication Number AP-80. January 1971.
9

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3.0	GENERAL EMISSION DATA REVIEW AND ANALYSIS PROCEDURES
3.1	LITERATURE SEARCH AND SCREENING
The first step of this investigation involved a search of available literature relating to
criteria and noncriteria pollutant emissions associated with chlor-alkali production. This search
included the following references:
1)	AP-42 background files maintained by the Emission Factor and Methodologies
Section.
2)	Files maintained by the Emission Standards Division.
3)	Handbook of Emission Factors, Parts I and II, Ministry of Health and Environmental
Protection, The Netherlands, 1980/1983.
4)	The EPA databases, including but not limited to the VOC/Particulate Matter (PM)
Speciation Database Management System (SPECIATE), the Crosswalk/Air Toxic
Emission Factor Data Base Management System (XATEF), and the Emission
Measurement Technical Information Center's Test Methods Storage and Retrieval
System (TSAR).
5)	The mercury NESHAP background report and docket, as well as the 1987 Review of
National Emission Standards for Mercury.
To reduce the amount of literature collected to a final group of references pertinent to this
report, the following general criteria were used:
1.	Emissions data must be from a primary reference, i.e. the document must constitute
the original source of test data. For example, a technical paper was not included if the
original study was contained in the previous document.
2.	The referenced study must contain test results based on more than one test run.
3.	The report must contain sufficient data to evaluate the testing procedures and source
operating conditions (e.g., one-page reports were generally rejected).
If no primary data was found and the previous update utilized secondary data, this
secondary data was still used and the Emission Factor Rating lowered, if needed. A final set of
reference materials was compiled after a thorough review of the pertinent reports, documents,
and information according to these criteria. The final set of reference materials is given in
Chapter 4.0.
10

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3.2	EMISSION DATA QUALITY RATING SYSTEM
As part of Pacific Environmental Services' analysis of the emission data, the quantity and
quality of the information contained in the final set of reference documents were evaluated. The
following data were always excluded from consideration.
1.	Test series averages reported in units that cannot be converted to the selected
reporting units;
2.	Test series representing incompatible test methods (i.e., comparison of the EPA
Method 5 front-half with the EPA Method 5 front- and back-half);
3.	Test series of controlled emissions for which the control device is not specified;
4.	Test series in which the source process is not clearly identified and described; and
5.	Test series in which it is not clear whether the emissions were measured before or
after the control device.
Data sets that were not excluded were assigned a quality rating. The rating system used
was that specified by the OAQPS for the preparation of AP-42 sections. The data were rated as
follows:
A
Multiple tests performed on the same source using sound methodology and reported in
enough detail for adequate validation. These tests do not necessarily conform to the
methodology specified in either the inhalable particulate (IP) protocol documents or the
EPA reference test methods, although these documents and methods were certainly used as
a guide for the methodology actually used.
B
Tests that were performed by a generally sound methodology but lack enough detail for
adequate validation.
11

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c
Tests that were based on an untested or new methodology or that lacked a significant
amount of background data.
D
Tests that were based on a generally unacceptable method but may provide an order-of-
magnitude value for the source.
The following criteria were used to evaluate source test reports for sound methodology
and adequate detail:
1.	Source operation. The manner in which the source was operated is well documented
In the report. The source was operating within typical parameters during the test.
2.	Sampling procedures. The sampling procedures conformed to a generally acceptable
methodology. If actual procedures deviated from accepted methods, the deviations
are well documented. When this occurred, an evaluation was made of the extent such
alternative procedures could influence the test results.
3.	Sampling and process data. Adequate sampling and process data are documented in
the report. Many variations can occur unnoticed and without warning during testing.
Such variations can induce wide deviations in sampling results. If a large spread
between test results cannot be explained by information contained in the test report,
the data are suspect and were given a lower rating.
4.	Analysis and calculations. The test reports contain original raw data sheets. The
nomenclature and equations used were compared to those (if any) specified by the
EPA to establish equivalency. The depth of review of the calculations was dictated by
the reviewer's confidence in the ability and conscientiousness of the tester, which in
turn was based on factors such as consistency of results and completeness of other
areas of the test report.
3.3	EMISSION FACTOR QUALITY RATING SYSTEM
The quality of the emission factors developed from analysis of the test data was rated
utilizing the following general criteria:
A (Excellent)
12

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Developed only from A-rated test data taken from many randomly chosen facilities in the
industry population. The source category is specific enough so that variability within the
source category population may be minimized.
B (Above average)
Developed only from A-rated test data from a reasonable number of facilities. Although no
specific bias is evident, it is not clear if the facilities tested represent a random sample of
the industries. As in the A-rating, the source category is specific enough so that variability
within the source category population may be minimized.
C (Average)
Developed only from A- and B-rated test data from a reasonable number of facilities.
Although no specific bias is evident, it is not clear if the facilities tested represent a
random sample of the industry. As in the A-rating, the source category is specific enough
so that variability within the source category population may be minimized.
D (Below average)
The emission factor was developed only from A- and B-rated test data from a small
number of facilities, and there is reason to suspect that these facilities do not represent a
random sample of the industry. There also may be evidence of variability within the source
category population. Limitations on the use of the emission factor are noted in the
emission factor table.
E (Poor)
The emission factor was developed from C- and D-rated test data, and there is reason to
suspect that the facilities tested do not represent a random sample of the industry. There
also may be evidence of variability within the source category population. Limitations on
the use of these factors are always noted.
The use of these criteria is somewhat subjective and depends to an extent on the individual
reviewer.
13

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3.4	REFERENCES FOR CHAPTER 3
1.	Technical Procedures for Developing AP-42 Emission Factors and Preparing AP-42
Sections. U.S. Environmental Protection Agency, Emissions Inventory Branch, Office of
Air Quality Planning and Standards, Research Triangle Park, NC, 27711, April, 1992.
[Note: this document is currently being revised at the time of this printing.]
2.	AP-42. Supplement A, Appendix C.2, "Generalized Particle Size Distributions." U.S.
Environmental Protection Agency, October, 1986.
14

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4.0	POLLUTANT EMISSION FACTOR DEVELOPMENT
4.1	REVIEW OF SPECIFIC DATA SETS
Reference 1: Atmospheric Emissions from Chlor-Alkali Manufacture
Reference 1 is a comprehensive study of the chlor-alkali industry from 1971 that provided
the only acceptable source of emissions data to develop chlorine emission factors for Section 5.5.
Reference 1 was also the only study used to generate emission factors for the April 1981 update
of AP-42 Section 5.5.
The reference has well-documented test procedures but no actual source tests to confirm
the results. The numbers quoted in the April 1981 update are a combination of quotes from the
text of Reference 1 and summary source test data contained in tables. Comments within the text
and appendices of Reference 1 generally agree with the numbers quoted in the April 1981
update, but there is little data to back up the quoted ranges. Some factors are based on
engineering judgement; others are based on telecons with industry representatives. The table
below summarizes the data taken from the text and used in Section 5.5. The last column
compares the factors found in this update with those used in the April 1981 update.
Category
Chlorine Emission Factor
(except as noted)
Reference 1
Page #
Source
April 1981
Section 5.5
Update
Diaphragm cell
1000 - 5000 kg/100 Mg
(2000 - 10000 lb/100 ton)
19
Unknown
No change
Mercury cell
2000 - 8000 kg/100 Mg
(4000 - 16000 lb/100 ton)
19
Unknown
No change
Returned tank car
vents
4.1 kg/Mg
(8.2 lb/ton)
20
Telecon
2.25 kg/Mg
(4.5 lb/ton)
Air blowing of
mercury brines
2.7 kg/Mg
(5.4 lb/ton)
22
Engineering
Estimate
2.5 kg/Mg
(5.0 lb/ton)
The first two categories have remained unchanged. The last two were changed due to
errors in transfer of the data from Reference 1. New emission factors for mercury cell losses are
discussed in Chapter 4.3.
15

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The emission factors for the remaining three emission categories found in Section 5.5 were
based on the source test results tabulated in Reference 1. Average emission factors for these three
categories are calculated below:
Water absorber
[(0.0003 + 0.0008 + 2.49)/3)] = 0.83 kg/Mg (1.66 lbs/ton)
Caustic scrubbers
[(0.0052 + 0.0002 + 0.0042 + 0.002 + 0.0027 + 0.0011 + 0.0038 + 0.034 + 0.0016 +
0.004)/10]= 0.006 kg/Mg (0.012 lb/ton)
Shipping container vents (based on 19 sources')
[(8.25 + 0.555 + 0.665 + 4.00 + 1.43 + 15.4 + 11.1 + 7.50 + 0.87 + 19.0 + 4.00 + 30.0 +
17.86 + 3.94 + 4.51 + 7.25 + 12.79 + 3.00 + 12.23)/19] = 8.66 kg/Mg
(17.3 lb/ton)
The average water absorber emission factor (0.83 kg/Mg) was used for this revision,
versus an estimated range (0.125 to 5 kg/Mg; 0.25 to 10 lb/ton) quoted in the April 1981 update.
Similarly, the caustic/lime scrubber value is now an average of the test results shown above. The
emission factor was previously 0.5 kg/Mg (1 lb/ton), a number that PES was unable to verify.
The "shipping container vents" category is now an average of 19 tests and was renamed (from
"storage tank vents") to more closely represent the data. The April 1981 version quoted an
emission factor of 6 kg/Mg (12 lbs/ton) for this category. This has been changed to 8.66 kg/Mg.
The Reference 1 study has been rated "C"; the AP-42 emission factors using this data were
downgraded to from "B" to "E." The drop in emission factor rating is due to the lack of primary
source test data needed to confirm the study results.
Reference 2: Stationary Source Samvlins Report, Reference No. 5593
Reference 2 is a mercury emissions source test report for the Linden Chemicals and
Plastics, Inc. chlor-alkali plant located in Riegelwood, North Carolina. Based on the criteria set
forth in Chapter 3.0 of this background report, the test was rejected for the following reasons:
1) Velocity measurements have conflicting documentation.
16

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2)	No calibration curve is reported.
3)	Pitot tube documentation was not found.
4)	No thermometer calibration data was found.
5)	There is no record of a post-test calibration.
Table 4.3-1 contains a summary of the test data. It has been included for information purposes
only.
Reference 3: B.F. Goodrich Chemical Company
Reference 3 contains mercury emissions source tests for the B.F. Goodrich chlor-alkali
plant in Calvert City, Kentucky. The tests were used to substantiate the 1973 mercury NESHAP.
The tests have been rated "C" due to the use of non-standard methods to obtain the results as well
as no calibration documentation. The data is contained in Table 4.3-1.
Reference 4: Diamond Shamrock Corporation
Reference 4 contains mercury emissions source tests for the Diamond Shamrock chlor-
alkali plant in Delaware City, Delaware. The tests were used to substantiate the 1973 mercury
NESHAP. The tests have been rated "C" due to the lack of calibration documentation as well as
the use of non-standard methods to obtain the test results. The data is contained in Table 4.3-1.
4.2	CRITERIA POLLUTANT EMISSIONS DATA
No data on emissions of volatile organic compounds, lead, sulfur dioxide, nitrogen oxides,
or total suspended particulate and PM10 were found or expected for the chlor-alkali process.
17

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Carbon monoxide.
Carbon monoxide (CO) is generated due to side reactions that occur in the chlor-alkali
production cells. No test data were found to elaborate on these reactions or to quantify the
emissions. Reference 1 estimates CO emissions in the blow gas to be 0.4 percent by volume.
4.3	NONCRITERIA POLLUTANT EMISSIONS DATA
Hazardous Air Pollutants.
Hazardous Air Pollutants (HAPs) are defined in the 1990 Clean Air Act Amendments.
Both mercury and chlorine are HAPs and are known emissions from the chlor-alkali process. See
Chapter 4.1 for a detailed discussion of the source tests included in Table 4.3-1.
Mercury emission factors for mercury cell plants were calculated using the data from
References 3 and 4. No other mercury emission data was found. The results utilizing the "B" and
"C" data only, are shown below.
Hydrogen Vent (Uncontrolled)
[(0.003 + 0.0003)/2] = 0.0017 kg mercury/Mg chlorine produced (0.0033 lbs/ton)
Hydrogen Vent (Controlled)
[(0.001 + 0.0002)/2] = 0.0006 kg mercury/Mg chlorine produced (0.0012 lbs/ton)
End Box
[(0.004 + 0.006)/2] = 0.005 kg mercury/Mg chlorine produced (0.010 lbs/ton)
These factors have replaced the previous engineering estimate of mercury cell loses (0.175
kg/Mg) quoted in the previous AP-42 Section 5.5.
18

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TABLE 4.3-1 (METRIC UNITS)
HAZARDOUS AIR POLLUTANTS: MERCURY EMISSIONS
Control
Equipment
Test
Rating
Test
Method
Run
#
Production
Rate3
Emission
Rateb
Emission
Factor0
Facility 2. H
ydrogen ventd





None
D
102
1
130
0.037
0.0003
2
130
0.047
0.0004
3
130
0.044
0.0003
Average
130
0.043
0.0003
Facility 2. End Boxd
None
D
102
1
130
0.015
0.0001
2
130
0.020
0.0002
3
130
0.020
0.0002
Average
130
0.018
0.0001
Facility 3. Hydrogen Vent
None
C
Unknown
1
272
0.869
0.003
2
272
0.950
0.003
3
272
0.607
0.002
Average
272
0.809
0.003
Facility 3. Hydrogen Vent
Demister
C
Unknown
1
272
0.282
0.001
2
272
0.374
0.001
3
272
0.508
0.002
Average
272
0.388
0.001
Facility 3. End Box
None
C
Unknown
1
272
1.44
0.005
2
272
1.08
0.004
3
272
0.802
0.003
Average
272
1.107
0.004
aUnits in Mg chlorine/day.
bUnits in kg mercury/day.
'Units in kg/Mg.
dReference 2.
19

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TABLE 4.3-1 (METRIC UNITS)
HAZARDOUS AIR POLLUTANTS: MERCURY EMISSIONS
(Concluded)
Control
Equipment
Test
Rating
Test
Method
Run
#
Production
Rate3
Emission
Rateb
Emission
Factor0
Facility 4. H
ydrogen vent





None
C
Unknown
1
363
0.285
0.0008
2
363
0.054
0.0002
3
363
0.080
0.0002
4
366
0.035
0.0001
Average
363
0.114
0.0003
Facility 4. Hydrogen Vent
Carbon
Absorber
C
Unknown
1
363
0.094
0.0003
2
363
0.029
0.0001
3
363
0.039
0.0001
4
363
0.089
0.0003
Average
363
0.063
0.0002
Facility 4. End Box
None
c
Unknown
1
363
2.20
0.006
2
363
2.98
0.008
3
363
1.74
0.005
4
363
1.82
0.005
5
363
2.14
0.006
6
363
1.36
0.004
Average
363
2.04
0.006
'Units in Mg chlorine/day.
bUnits in kg mercury/day.
Units in kg/Mg.
dReference 2.
20

-------
TABLE 4.3-1 (ENGLISH UNITS)
HAZARDOUS AIR POLLUTANTS: MERCURY EMISSIONS
Control
Equipment
Test
Rating
Test
Method
Run
#
Production
Rate3
Emission
Rateb
Emission
Factor0
Facility 2. H
ydrogen ventd





None
D
102
1
143.5
0.082
0.0006
2
143.5
0.104
0.0007
3
143.5
0.097
0.0007
Average
143.5
0.094
0.0007
Facility 2. End Boxd
None
D
102
1
143.5
0.033
0.0002
2
143.5
0.044
0.0003
3
143.5
0.043
0.0003
Average
143.5
0.040
0.0003
Facility 3. Hydrogen Vent
None
C
Unknown
1
300
1.92
0.006
2
300
2.10
0.007
3
300
1.34
0.004
Average
300
1.79
0.006
Facility 3. Hydrogen Vent
Demister
C
Unknown
1
300
0.622
0.002
2
300
0.826
0.003
3
300
1.12
0.004
Average
300
0.856
0.003
Facility 3. End Box
None
C
Unknown
1
300
3.17
0.011
2
300
2.38
0.008
3
300
1.77
0.006
Average
300
2.44
0.008
aUnits in tons chlorine/day.
bUnits in lb mercury/day.
Units in lb/ton.
dReference 2.
21

-------
TABLE 4.3-1 (ENGLISH UNITS)
HAZARDOUS AIR POLLUTANTS: MERCURY EMISSIONS
(Concluded)
Control
Equipment
Test
Rating
Test
Method
Run
#
Production
Rate3
Emission
Rateb
Emission
Factor0
Facility 4. H
ydrogen vent





None
C
Unknown
1
400
0.629
0.002
2
400
0.120
0.0003
3
400
0.175
0.0004
4
400
0.077
0.0002
Average
400
0.333
0.0008
Facility 4. Hydrogen Vent
Carbon
Absorber
C
Unknown
1
400
0.206
0.0005
2
400
0.065
0.0002
3
400
0.086
0.0002
4
400
0.200
0.0005
Average
400
0.139
0.0004
Facility 4. End Box
None
c
Unknown
1
400
4.84
0.012
2
400
6.58
0.016
3
400
3.84
0.010
4
400
4.02
0.010
5
400
4.72
0.012
6
400
2.98
0.007
Average
400
4.50
0.011
"Units in tons chlorine/day.
bUnits in lb mercury/day.
Units in lb/ton.
dReference 2.
22

-------
Chlorine emissions from the previous AP-42 Section 5.5 were based solely on the results of
Reference 1. Data for the water absorber and scrubber control devices, and uncontrolled shipping container
loading emissions are shown in Table 4.3-2.
The average emission factors are shown below:
Water absorber
0.83 kg/Mg (1.66 lbs/ton)
Caustic scrubbers
0.006 kg/Mg (0.012 lb/ton)
Shipping container vents
8.66 kg/Mg (17.3 lb/ton)
The data from Reference 1 has been rated "C." Each factor is rated "E." See Section 4.1 for a detailed
discussion of Reference 1.
23

-------
TABLE 4.3-2 (METRIC UNITS)
HAZARDOUS AIR POLLUTANTS: CHLORINE EMISSIONS
Control
Equipment
Test
Rating
Test
Method
Run
#
Production
Rate1
Emission
Rateb
Emission
Factor0
Facility l.d SI
lipping contaii
icr vents




None
C
Unknown
Average
218
1814
8.35
Facility 2.d Shipping container vents
None
C
Unknown
Average
163
90.7
0.555
Facility 3.d Shipping container vents
None
c
Unknown
Average
316
90.7
0.665
Facility 4.d Shipping container vents
None
c
Unknown
Average
45
181.4
4.00
Facility 6.d Shipping container vents
None
c
Unknown
Average
64
90.7
1.43
Facility 7.d Shipping container vents
None
c
Unknown
Average
59
907.2
15.4
Facility 8.d Shipping container vents
None
c
Unknown
Average
163
1814.4
11.1
Facility 9.d Shipping container vents
None
c
Unknown
1
45
226.8
5.00
2
45
453.4
10.00
Average
45
340.2
7.50
Facility 10.d Shipping container vents
None
c
Unknown
Average
209
181.4
0.87
Facility ll.d Shipping container vents
None
c
Unknown
1
72
907.2
12.65
2
72
1814.4
25.3
Average
72
1360.8
19.0
aUnits in Mg/day.
bUnits in kg/day.
"Units in kg/Mg.
dReference 1.
24

-------
TABLE 4.3-2 (METRIC UNITS) (.continued)
HAZARDOUS AIR POLLUTANTS: CHLORINE EMISSIONS
Control
Equipment
Test
Rating
Test
Method
Run
#
Production
Ratea
Emission
Rateb
Emission
Factor0
Facility 12.d
Shipping ct
intaincr vents




None
C
Unknown
Average
227
907.2
4.00
Facility 13.d
Shipping container vents




None
C
Unknown
Average
91
2721.6
30.00
Facility 14.d
Shipping container vents




None
C
Unknown
Average
102
1814.4
17.86
Facility 15.d
Shipping container vents




None
C
Unknown
Average
230
907.2
3.94
Facility 19.d
Shipping container vents




None
C
Unknown
Average
201
907.2
4.51
Facility 20.d
Shipping container vents




None
C
Unknown
Average
125
907.2
7.25
Facility 21.d
Shipping container vents




None
C
Unknown
Average
172
2204.5
12.79
Facility 22."
Shipping container vents




None
C
Unknown
Average
163
272.16
3.00
Facility 25.d
Shipping container vents




None
C
Unknown
Average
415
5080.3
12.23
Facility l.d Liquefaction blow gases
Caustic
Scrubber
C
Unknown
Average
218
1.13
0.0052
Facility 4.d Liquefaction blow gases
Caustic
Scrubber
c
Unknown
Average
45
0.0084
0.0002
aUnits in Mg/day.
bUnits in kg/day.
'Units in kg/Mg.
dReference 1.
25

-------
TABLE 4.3-2 (METRIC UNITS) (.continued)
HAZARDOUS AIR POLLUTANTS: CHLORINE EMISSIONS
Control
Equipment
Test
Rating
Test
Method
Run
#
Production
Rate1
Emission
Rateb
Emission
Factor0
Facility 7.d L
iquefaction bio
w gases




Water
Absorber
C
Unknown
Average
59
0.015
0.0003
Facility 9.d Liquefaction blow gases
Caustic
Scrubber
C
Unknown
Average
45
0.188
0.0042
Facility 10.d
Liquefaction blow gases




Caustic
Scrubber
C
Unknown
Average
209
0.408
0.0020
Facility 12.d
Liquefaction blow gases




Caustic
Scrubber
C
Unknown
Average
236
0.628
0.0027
Facility 13.d
Liquefaction blow gases




Caustic
Scrubber
C
Unknown
Average
118
0.126
0.0011
Facility 14.d
Liquefaction blow gases




Caustic
Scrubber
C
Unknown
Average
102
0.387
0.0038
Facility 25.d
Liquefaction blow gases




Water
Absorber
C
Unknown
Average
279
0.211
0.0008
Facility 28.d
Liquefaction blow gases




Caustic
Scrubber
C
Unknown
Average
336
0.537
0.0016
Facility 29.d
Liquefaction blow gases




Caustic
scrubber
C
Unknown
Average
127
4.33
0.034
"Units in Mg/day.
bUnits in kg/day.
Units in kg/Mg.
dReference 1.
26

-------
TABLE 4.3-2 (METRIC UNITS) (.concluded)
HAZARDOUS AIR POLLUTANTS: CHLORINE EMISSIONS
Control
Equipment
Test
Rating
Test
Method
Run
#
Production
Rate1
Emission
Rateb
Emission
Factor0
Facility 30.d
Liquef actio
n blow gases




Water
absorber
C
Unknown
1
163
1012
6.2
2
154
298
1.93
3
135
72
0.53
4
108
13
0.12
Average
141
349
2.49
Facility 31.d Liquefaction blow gases
Caustic
Scrubber
C
Unknown
Average
287
1.17
0.004
aUnits in Mg/day.
bUnits in kg/day.
'Units in kg/Mg.
dReference 1.
27

-------
TABLE 4.3-2 (ENGLISH UNITS)
HAZARDOUS AIR POLLUTANTS: CHLORINE EMISSIONS
Control
Equipment
Test
Rating
Test
Method
Run
#
Production
Rate1
Emission
Rateb
Emission
Factor0
Facility l.d SI
lipping contaii
icr vents




None
C
Unknown
Average
240
4000
16.7
Facility 2.d Shipping container vents
None
C
Unknown
Average
180
200
1.11
Facility 3.d Shipping container vents
None
c
Unknown
Average
150
200
1.33
Facility 4.d Shipping container vents
None
c
Unknown
Average
50
400
8.00
Facility 6.d Shipping container vents
None
c
Unknown
Average
70
200
2.86
Facility 7.d Shipping container vents
None
c
Unknown
Average
65
2000
30.8
Facility 8.d Shipping container vents
None
c
Unknown
Average
180
4000
22.2
Facility 9.d Shipping container vents
None
c
Unknown
1
50
500
10.00
2
50
1000
20.00
Average
50
750
15.00
Facility 10.d Shipping container vents
None
c
Unknown
Average
230
400
1.74
Facility ll.d Shipping container vents
None
c
Unknown
1
79
2000
25.3
2
79
4000
50.6
Average
79
3000
38.0
aUnits in tons/day.
bUnits in lb/day.
cUnits in lb/ton.
dReference 1.
28

-------
TABLE 4.3-2 (ENGLISH UNITS) (.continued)
HAZARDOUS AIR POLLUTANTS: CHLORINE EMISSIONS
Control
Equipment
Test
Rating
Test
Method
Run
#
Production
Rate1
Emission
Rateb
Emission
Factor0
Facility 12.d
Shipping ct
intaincr vents




None
C
Unknown
Average
250
2000
8.00
Facility 13.d
Shipping container vents




None
C
Unknown
Average
100
6000
60.00
Facility 14.d
Shipping container vents




None
C
Unknown
Average
112
4000
35.71
Facility 15.d
Shipping container vents




None
C
Unknown
Average
254
2000
7.87
Facility 19.d
Shipping container vents




None
C
Unknown
Average
222
2000
9.01
Facility 20.d
Shipping container vents




None
C
Unknown
Average
138
2000
14.49
Facility 21.d
Shipping container vents




None
C
Unknown
Average
190
4860
25.58
Facility 22.d
Shipping container vents







Average
180
600
6.00
Facility 25.d
Shipping container vents




None
C
Unknown
Average
458
11200
24.45
Facility l.d Liquefaction blow gases
Caustic
Scrubber
C
Unknown
Average
240
2.48
0.0104
Facility 4.d Liquefaction blow gases
Caustic
scrubber
c
Unknown
Average
50
0.0185
0.0004
aUnits in tons/day.
bUnits in lb/day.
cUnits in lb/ton.
dReference 1.
29

-------
TABLE 4.3-2 (ENGLISH UNITS) (continued)
HAZARDOUS AIR POLLUTANTS: CHLORINE EMISSIONS
Control
Equipment
Test
Rating
Test
Method
Run
#
Production
Ratea
Emission
Rateb
Emission
Factor0
Facility 7.d L
iquefaction bio
w gases




Water
Absorber
C
Unknown
Average
65
0.0335
0.0005
Facility 9.d Liquefaction blow gases
Caustic
Scrubber
C
Unknown
Average
50
0.4154
0.0083
Facility 10.d
Liquefaction blow gases




Caustic
Scrubber
C
Unknown
Average
230
0.90
0.0039
Facility 12.d
Liquefaction blow gases




Caustic
Scrubber
C
Unknown
Average
260
1.39
0.0053
Facility 13.d
Liquefaction blow gases




Caustic
Scrubber
C
Unknown
Average
130
0.277
0.0021
Facility 14.d
Liquefaction blow gases




Caustic
Scrubber
C
Unknown
Average
112
0.854
0.0076
Facility 25.d
Liquefaction blow gases




Water
Absorber
C
Unknown
Average
308
0.466
0.0015
Facility 28.d
Liquefaction blow gases




Caustic
Scrubber
C
Unknown
Average
370
1.18
0.0032
Facility 29.d
Liquefaction blow gases




Caustic
scrubber
C
Unknown
Average
140
9.56
0.068
aUnits in Mg/day.
bUnits in kg/day.
"Units in kg/Mg.
dReference 1.
30

-------
TABLE 4.3-2 (ENGLISH UNITS) (.concluded)
HAZARDOUS AIR POLLUTANTS: CHLORINE EMISSIONS
Control
Equipment
Test
Rating
Test
Method
Run
#
Production
Rate1
Emission
Rateb
Emission
Factor0
Facility 30.d
Liquef actio
n blow gases




Water
absorber
C
Unknown
1
180
2232
12.4
2
170
658
3.86
3
149
158
1.06
4
119
30
0.25
Average
155
770
4.98
Facility 31.d Liquefaction blow gases
Caustic
scrubber
C
Unknown
Average
316
2.58
0.008
aUnits in tons/day.
bUnits in lb/day.
Units in lb/ton.
dReference 1.
31

-------
Global Warming Gases.
Pollutants such as methane, carbon dioxide, and N20 have been found to contribute to
overall global warming. No data on emissions of methane and N20 were found for the chlor-
alkali process.
Carbon dioxide emissions were found for Plant 30 in Reference 1 and are listed in Table
4.3-3. The data has been rated "C." Reference 1 contains only C02 emission factors from plants
that generate C02 from the oxidation of graphite anodes and the decomposition of feed brine (as
discussed in Section 2.3). Conversations with industry members indicate that graphite anodes are
no longer used, making this data obsolete. For this reason, no C02 emission factor was shown in
the AP-42 update.
32

-------
TABLE 4.3-3 (METRIC UNITS)
GLOBAL WARMING GASES: CARBON DIOXIDE
Control
Test
Test
Run
Production
Emission
Emission
Equipment
Rating
Method
#
Ratea
Rateb
Factor0
Facility 30.d






None
C
Unknown
1


1.55



2


2.14



3


2.17



4


2.24



Average


2.03
aUnits in Mg/day.
bUnits in kg/day.
"Units in kg/Mg.
dReference 1.
TABLE 4.3-3 (ENGLISH UNITS)
GLOBAL WARMING GASES: CARBON DIOXIDE
Control
Test
Test
Run
Production
Emission
Emission
Equipment
Rating
Method
#
Ratea
Rateb
Factor0
Facility 30.d






None
C
Unknown
1


3.10



2


4.28



3


4.34



4


4.48



Average


4.05
"Units in tons/day.
bUnits in lb/day.
cUnits in lb/ton.
dReference 1.
33

-------
4.4	DATA GAP ANALYSIS
As noted in Chapter 4.1, the data for developing emission factors for Section 5.5, Chlor-
Alkali Industry is far from ideal. PES was unable to obtain any reliable and/or recent primary
source test data for this industrial category. The existing information is out-of-date and, for the
most part, unverifiable. A NESHAP is currently under development for this category which will
include source testing to quantify current emissions. The results of this work should be available
in 1993 and should be used to update the emission factors as well as provide the most up-to-date
process descriptions. If source testing is dropped from the NESHAP scope of work, PES
recommends that either the chlor-alkali industry be encouraged to supply their most recent source
test data so that the emission factors can be updated for this section or a source testing program
be undertaken to quantify emissions from the industry. Reliable data is needed to quantify
emissions of chlorine, C02, CO and mercury. Closer inspection of State files, particularly in
Louisiana, may also yield source tests that could be used to improve the quality of the emission
factors.
34

-------
TABLE 4.5-1
LIST OF CONVERSION FACTORS
Multiply:
by:
To obtain:
mg/dscm
4.37 x 10"4
gr/dscf
m2
10.764
ft2
acm/min
35.31
acfm
m/s
3.281
ft/s
kg/hr
2.205
lb/hr
Kpa
1.45 x 101
psia
kg/Mg
2.0
lb/ton
Mg
1.1023
ton
Temperature conversion equations:
Fahrenheit to Celsius:
oc = (°F-32)
1.8
Celsius to Fahrenheit:
°F = 1.8(°C) + 32
35

-------
4.5	REFERENCES FOR CHAPTER 4
1.	Atmospheric Emissions from Chlor-Alkali Manufacture. U.S. EPA, Air Pollution Control
Office. Research Triangle Park, N.C. Publication Number AP-80. January 1971.
2.	Stationary Source Sampling Report. Reference No. 5593. Entropy Environmentalists Inc.,
Research Triangle Park, NC. September 1987.
3.	B.F. Goodrich Chemical Company Chlor-Alkali Plant Source Tests. Calvert City.
Kentucky. Roy F. Weston, Inc., EPA Contract No. CPA 70-132. May 1972.
4.	Diamond Shamrock Corporation Chlor-Alkali Plant Source Tests. Delaware City.
Delaware. Roy F. Weston, Inc., EPA Contract No. CPA 70-132. June 1972.
36

-------
APPENDIX A.
AP-42 SECTION 5.5
[Not presented here. See instead current AP-42 Section 8.11.]
37

-------