EPA-600/2-77-023J
February 1977
Environmental Protection Technology Series
INDUSTRIAL PROCESS PROFILES FOR
ENVIRONMENTAL USE: Chapter 9.
The -Synthetic Rubber Industry
Industrial Environmental Research laboratory
Office of Research and Develemnenl
U.S. Environmental Protection Agen?
Cincinnati. Ohio 452F
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into five series. These five broad
categories were established to facilitate further development and application of
environmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The five series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
This report has been assigned to the ENVIRONMENTAL PROTECTION
TECHNOLOGY series. This series describes research performed to develop and
demonstrate instrumentation, equipment, and methodology to repair or prevent
environmental degradation from point and non-point sources of pollution. This
work provides the new or improved technology required for the control and
treatment of pollution sources to meet environmental quality standards.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/2-77-0231
February 1977
INDUSTRIAL PROCESS PROFILES
FOR ENVIRONMENTAL USE
CHAPTER 9
THE SYNTHETIC RUBBER INDUSTRY
by
Jerry Parr, Terry B. Parsons and Nancy P. Phillips
Radian Corporation
Austin, Texas 78766
Contract No. 68-02-1319
Project Officer
Alfred B. Craig
Metals and Inorganic Chemicals Branch
Industrial Environmental Research Laboratory
Cincinnati, Ohio 45268
INDUSTRIAL ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
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DISCLAIMER
This report has been reviewed by the Industrial Environmental Research
Laboratory - Cincinnati, U.S. Environmental Protection Agency, and approved
for publication. Approval does not signify that the contents necessarily
reflect the views and policies of the U.S. Environmental Protection Agency,
nor does mention of trade names or commercial products constitute endorsement
or recommendation for use.
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TABLE OF CONTENTS
CHAPTER 9
Page
INDUSTRY DESCRIPTION 1
Raw Materials 3
Products 4
Companies 4
Environmental Impact 6
Bibliography 16
INDUSTRY ANALYSIS 18
Emu!sion Crumb Production Processes 19
Process No. 1. Monomer Storage 22
Process No. 2. Caustic Wash 24
Process No. 3. Polymerization 26
Process No. 4. Light Monomer Recovery 29
Process No. 5. Heavy Monomer Recovery 32
Process No. 6. Coagulation and Screening 34
Process No. 7. Crumb Washing, Drying, and Finishing 36
Latex Production Processes 38
Process No. 8. Polymerization 41
Process No. 9. Light Monomer Removal 42
Process No. 10. Heavy Monomer Removal 43
Process No. 11. Blending, Storage, and Shipping 44
Sol ution Crumb Production Processes 45
Process No. 12. Feed Drying 49
Process No. 13. Polymerization 51
Process No. 14. Cement Storage 53
Process No. 15. Stripping and Coagulation 54
Process No. 16. Monomer and Solvent Recovery 55
Process No. 17. Dewatering and Product Finishing 57
APPENDIX A - Raw Materials Lists 59
iii
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TABLE OF CONTENTS (Concluded)
CHAPTER 9
Page
APPENDIX B - Products 69
APPENDIX C - Producers 75
iv
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LIST OF FIGURES
CHAPTER 9
g ure Page
1 PROCESS DIAGRAM FOR EMULSION CRUMB OPERATION 21
2 LATEX PRODUCTION PROCESSES 40
3 FLOW DIAGRAM FOR SOLUTION CRUMB PRODUCTION 48
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LIST OF TABLES
CHAPTER 9
Table Page
1 SYNTHETIC RUBBER PRODUCTION, 1976 2
2 RAW MATERIALS CONSUMED BY THE SYNTHETIC RUBBER INDUSTRY,
1972 2
3 ENERGY REQUIREMENTS FOR THE SYNTHETIC RUBBER INDUSTRY 3
4 SYNTHETIC RUBBER PRODUCTS 5
5 CAPACITY OF TEN LARGEST SYNTHETIC FIBER PRODUCERS 6
6 ORGANIC COMPOUNDS IDENTIFIED IN EFFLUENTS FROM SYNTHETIC
PLANTS 8
7 RAW WASTE LOADS FOR SOME EMULSION CRUMB RUBBER PLANTS 10
8 RAW WASTE LOADS FOR SOME SOLUTION CRUMB RUBBER PLANTS 11
9 RAW WASTE LOADS FOR SOME LATEX RUBBER PLANTS 12
10 CHARACTERISTICS OF TREATED EFFLUENTS FROM SYNTHETIC RUBBER
PRODUCTION PROCESSES 13
11 SOURCE CLASSIFICATION CODES FOR SYNTHETIC RUBBER 15
12 MAJOR FEEDSTOCKS AND PRODUCTS FOR EMULSION CRUMB PRODUCTION. 19
13 RAW WASTE LOADS FOR SOME CRUMB RUBBER PLANTS 19
14 MAJOR RAW MATERIALS USED AS MONOMERS 22
15 INHIBITOR CONCENTRATIONS FOR STORAGE OF STYRENE AND
BUTADIENE 22
16 OPERATING PARAMETERS FOR POLYMERIZATION 27
17 COMPOSITION OF LATEX BEFORE MONOMER RECOVERY 29
18 RAW WASTE LOADS FROM MONOMER RECOVERY PROCESSES 30
19 WASTE LOAD FOR COAGULATION LIQUOR OVERFLOW FOR EMULSION
CRUMB PRODUCTION 35
20 AVERAGE WASTE LOADS FOR CRUMB RINSE OVERFLOW IN EMULSION
CRUMB PRODUCTION 36
21 AVERAGE RAW WASTE LOADS FOR LATEX RUBBER PLANTS 38
VI
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LIST OF TABLES (Continued)
CHAPTER 9
Table Page
22 COMPOUNDS IDENTIFIED IN LATEX PLANT RAW EFFLUENT 39
23 COMPOUNDS IDENTIFIED IN LATEX PLANT HOLDING POND 39
24 MAJOR FEEDSTOCKS AND PRODUCTS FOR SOLUTION CRUMB
PRODUCTION 45
25 UTILITY REQUIREMENTS FOR THE PRODUCTION OF THREE TYPES
OF SOLUTION CRUMB 46
26 RAW WASTE LOADS FOR SOME SOLUTION CRUMB RUBBER PLANTS 47
27 INPUT MATERIALS TO FEED DRYING 49
28 OPERATING CONDITIONS FOR SOLUTION POLYMERIZATION 51
29 ORGANIC VAPORS RELEASED FROM PURGE VENTS IN EPM PRODUCTION.. 55
A-l MONOMERS USED IN THE SYNTHETIC RUBBER INDUSTRY 60
A-2 SOME CATALYSTS USED IN SOLUTION CRUMB PRODUCTION 61
A-3 SOLVENTS USED IN SOLUTION CRUMB PRODUCTION 62
A-4 CARBON BLACK ASTM GRADE DESIGNATIONS 63
A-5 POLYMERIZATION ADDITIVES 64
A-6 EMULSIFIERS 65
A-7 RECIPIES FOR SOME ELASTOMER PRODUCTS 66
A-8 OTHER RAW MATERIALS USED BY THE SYNTHETIC RUBBER INDUSTRY... 68
B-l GENERAL PHYSICAL PROPERTIES OF SNYTHETIC ELASTOMERS 70
B-2 TYPICAL TRADE NAMES AND SUPPLIERS FOR ELASTOMERS 71
B-3 THE IISRP NUMBERING SYSTEM FOR SBR 72
B-4 THE IISRP NUMBERING SYSTEM FOR STEREO AND RELATED RUBBERS... 72
B-5 USE OF VARIOUS SYNTHETIC ELASTOMERS IN THE UNITED STATES
(1962) 73
C-l COMPANY PRODUCT LIST 76
C-2 LOCATION OF U.S. SYNTHETIC RUBBER PRODUCING PLANTS 82
C-3 U.S. PRODUCTION OF SOME SPECIALTY ELASTOMERS, 1967 83
vii
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ACKNOWLEDGEMENTS
Some of the technical information used in preparing this catalog entry
was supplied to EPA by Monsanto Research Corporation, Dayton Laboratory,
under Contract No. 68-02-1320, Task 17. The contributions of Duane E.
Earley are gratefully acknowledged. Mr. William Medley was Project
Leader.
This catalog entry was prepared for EPA by Radian Corporation under
Contract No. 68-02-1319, Task 52. The authors were Jerry L. Parr,
Terry B. Parsons, and Nancy P. Phillips. Contributions by Judith
D. Whiting and Cherry J. Scholin are gratefully acknowledged. Eugene
C. Cavanaugh was the Program Manager.
Helpful review comments from Dr. Paul F. Bruins were received and
incorporated in the chapter.
vi 11
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SYNTHETIC RUBBER INDUSTRY
INDUSTRY DESCRIPTION
The Synthetic Rubber Industry described in this chapter is comprised of com-
panies which produce a synthetic vulcanizable elastomer (rubber) by polymerization
or copolymerization of monomers derived from petroleum or natural gas. An
elastomer is hereby defined as a substance which can be processed (vulcanized)
into a material that can be stretched to at least twice its original length
and, after having been so stretched and the stress removed, will return with
force to approximately its original length. Secondary raw materials used to
produce elastomers include butadiene, styrene, ethylene, proplyene, isoprene,
isobutylene, acrylonitrile, and chloroprene. Products are marketed in both
solid (crumb) and liquid (latex) forms.
Tire rubber companies generally produce high volumes of several types of
synthetic rubbers, particularly styrene-butadiene rubber (SBR). Specialty
rubber companies have a more diverse product line and lower production volumes.
The synthetic rubber process flow sheet has been divided into three opera-
tions involving similar processes. The three operations are: 1) Emulsion
Crumb Production, 2) Latex Production, and 3) Solution Crumb Production.
Processes which are common to all three operations are polymerization, monomer
storage, and caustic washing. Other processes include coagulation, monomer
recovery and monomer removal.
The 1976 Directory of Chemical Producers indicates there are 111 facilities
for producing synthetic elastomers. The plants vary in size from small specialty
plants employing fewer than ten people to large tire rubber producing plants
with production capacities exceeding 350 Gg/yr. Commercial establishments
engaged in manufacturing elastomers, rubber-like materials capable of vulcani-
zation, by polymerization or copolymerization are classified in SIC Code 2822.
In 1972, 12,000 persons were employed in establishments classified in SIC Code
2822 with 8,000 of these being production workers. Table 1 shows the produc-
tion of the major synthetic rubbers, by product, for 1976. Table 2 lists
some of the raw materials consumed by the synthetic rubber industry in 1972.
Most synthetic elastomer manufacturing facilities are located noar major
petroleum refining areas. Over half of the facilities are located in the
states of California, Louisiana, New Jersey, Ohio and Texas. Table C-2 in
Appendix C shows the number of plants in each state and the products produced
by those plants.
Automobile tire production greatly influences growth in the synthetic rub-
ber industry. Factors such as longer wearing tires, increased usage of natural
rubber in some tires, and decreases in buying of replacement tires have resulted
in lower synthetic rubber production for 1975. Non-tire uses of synthetic
rubber, which account for 44 percent of all production, have also decreased.
The biggest market in this area is in hose and belting. Demand for these pro-
ducts varies with industrial activity.
Elastomer producers look for continued growth with 1980 production estimates
at 2790 Gg. Growth rates are based on anticipated increases in automobiles
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Table 1. SYNTHETIC RUBBER PRODUCTION, 1976a
Material Production, Gg (106 Ibs.)
Styrene-butadiene (SBR)b 1179 (2600)
Butadiene (PER) 290 (640)
Butyl (IIR) 80 (176)
Nitrile (NBR) 55 (121)
Isoprene (IR) 61 (134)
Ethylene-propylene (EPM) 84 (185)
Neoprene (CR) 144 (317)
Other0 47 (104)
TOTAL 1940 4277
aPremilinary
^Excludes high styrene latex
cExcludes polyurethane rubber
Source: Production Fell, Often Sharply, Last Year for All Major
Chemical Products. C&EN 54_(74):37, June 7, 1976.
Table 2. RAW MATERIALS CONSUMED BY THE SYNTHETIC RUBBER INDUSTRY, 1972
Material
Acrylonitrile
Carbon Black
Extender Oils
Butadiene
Sodium Hydroxide
Styrene
Sulfuric Acid
Consumption (Gg)
33.8
166.7
331.5
1143.5
47. la
286.8
73.4
a!967 consumption
Source: U.S. Department of Commerce. Bureau of Census. 1972 Census of
Manufacturers, "astics Materials, Synthetic Rubber, and Man-
made Fibers. November 1974: SIC 282
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and replacement tire sales. The non-tire usage of elastomers should increase
as the need for automated equipment increases. Other specialized uses of
elastomers such as tank linings and rotary oil drilling hose should also grow.
Labor disputes in the tire and rubber industries could also greatly affect
future consumption of elastomers.
Synthetic rubber plants require steam in many of the processes. This
steam is generated on site for many plants and bought by others. Energy re-
quirements for the synthetic rubber industry are summarized in Table 3.
Table 3. ENERGY REQUIREMENTS FOR THE SYNTHETIC RUBBER INDUSTRY
Purchased Fuel Quantity
Coal 216.1 Gg
Fuel Oil 27.9 Mm3
Natural Gas 328 Mm3
Purchased Electrical Energy 510.9 GWh
Generated Electrical Energy 1306.2 GWh
Total Energy Used for Heat and Power 24.0 TWh
Source: U.S. Department of Commerce, Bureau of the Census. 1972 Census of Manu-
facturers, Plastics Materials, Synthetic Rubber, and Man-made Fibers.
November, 1974.
Raw Materials
Ethylene, propylene, isobutylene, methane, benzene, and butylene are the
basic petrochemical feedstocks used to produce monomers for use in the synthetic
rubber industry. These feedstocks are used directly as monomers or as feed-
stocks to produce other monomers such as butadiene, styrene, chloroprene,
acrylonitrile, and isoprene. A complete list of all monomer feedstocks is given
in Table A-l in Appendix A. The tire and rubber industries consume 90 to 95
percent of all the carbon black produced in the United States. A large portion
of this is used in the synthetic rubber industry for masterbatching. Master-
batching is a method for mixing rubber and carbon black by coprecipitation
of a rubber latex and a carbon black slurry. Many types of carbon black are
used, differing mainly in particle size, surface conditions, and degree of
agglomeration. The two most widely used are ISAF and HAF blacks. Table A-4
in Appendix A lists ASTM designations for some carbon blacks. About 90 percent
of the synthetic rubber produced in the United States is extended with hydro-
carbon oils. Petroleum oils used for this purpose include naphthenic, aromatic
and highly aromatic oils. Extenders such as carbon black or oil can comprise
as much as 50 percent of the rubber produced.
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Other materials used directly in elastomer production include anti-oxidants,
catalysts, initiators, reaction terminators (shortstops), soaps, modifiers and
other additives. The total amount of these materials used is generally less
than 5 percent of the total input. Sodium hydroxide, sulfuric acid, and sodium
chloride are used in some of the processes. Solution crumb production requires
a variety of organic solvents such as hexane, toluene, or methyl chloride.
Tables A-2 through A-8 in Appendix A list some of these raw materials.
The liquid feedstocks are normally tanked or piped into the plant. One
plant investigated in an EPA report did have a butadiene plant located inside
the plant complex. The carbon black is brought in by railroad car. Unloading
and conveying operations produce fugitive emissions of fines. A liquid waste
stream laden with fine carbon black particles is generated as a result of area
washdowns.
Products
The synthetic rubber industry produces a variety of products for use by
fabrication industries. Table B-5 in Appendix B lists uses of some
synthetic rubbers. Products are generally included in one of two classes,
tire rubbers or specialty rubbers. Tire rubbers are high production volume
commodities used predominantly by the tire industry and supplied in a solid
form termed crumb. Tire rubbers are also used to manufacture hose, belting,
footwear, and other non-tire items. The major tire rubbers are styrene-
butadiene, polybutadiene, polyisoprene, butyl, and polyethylene-propylene.
Nitrile and neoprene are often listed with tire rubbers because of their high
volume of production.
Specialty rubbers include a wider variety of products and have many di-
verse applications. Uses of specialty rubbers include seals, gaskets, 0-rings,
hose, tubing, caulking compounds, adhesives, shoes, wire and cable insulation
and electrical tape.
This chapter describes primarily the production of the high-volume tire
rubbers. Some of the specialty rubbers are manufactured in basically the
same fashion. Polyurethane, silicone, fluorocarbon, and polysulfide rubbers
are produced using different processes which are not discussed in this chapter
because of their low volume of sales. Table C-3 in Appendix C gives production
figures for some specialty elastomers.
In summary, synthetic rubbers are produced in either liquid (latex) or
solid (crumb) form. They may be non-extended, oil-extended, carbon-black ex-
tended, or oil-and-carbon-black extended. Table 4 lists the types of synthetic
rubber products produced, their ASTM designations, and some uses for each
rubber. Tables B-l through B-5 in Appendix B give information about properties
and uses of synthetic rubber products.
Companies
As of January 1, 1976, there were 71 companies which comprised the synthetic
rubber industry. The companies operated 141 plants in 26 states. Most of the
larger facilities are located near petrochemical companies because they are
dependent on basic petrochemicals for their feedstocks. Manufacturers of
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TABLE 4: SYNTHETIC RUBBER PRODUCTS
Designation (D1418)
IR
SBR
CR
NBR
IIR
EPM
EPDM
CSM
ABR
T
SI, FSI,
PSI, VSI,
PVSI
U
FPM
PBR
COX
CO, ECO
PVC, NBR
Common Names
Isoprene Rubber,
Polyisoprene
GR-S
Neoprene
Buna-N,
Nitrile Rubber
Butyl
EPR
EPT
Hypalon
Acryl i c
Polysulfide Thiokol
Si 1i cone
Urethane
Fluoroelastotner
Butadiene
Carboxyl i c
Hydrin
Hycar
Chemical Composition
Isoprene
Styrene-Butadiene
Chloroprene
Butadiene- Aery 1-
onitrile
Isobutylene-
Isoprene
Ethylene-Propylene
Ethyl ene-Propy 1 ene ,
Cyclooctadiene
Chlorosulfonated
Ethyl ene
Acryl ate Butadiene
Organic Sulfide
Dimethyl Siloxanes
Diisocyanates and
Polyalkylene Ether
Glycols
Uses
Tire Treads
Tire Treads
Multi purpose-
Widely Used
Hose, Seals,
Gaskets, 0-Rings
Inner Tubes
Wire Insulation, Tires,
Mechanical Rubber Goods
Tires, Mechanical Rubber
Goods
Wire Insulation, Shoes,
Lining, Paint
Seals, Hosing, Tubing
Sealing, Glazing,
Hose
Seal, Gaskets, Electrical
Tape
Rollers, Fibers, Solid
Tires, Foams
Vinylidene Fluoride Seals, Gaskets, 0-Rings
and Hexafluoropropylene High-Temperature Service
Polybutadiene
Butadiene-
Acrylonitrile
modified with
Carboxylic Groups
Epichlorohydrin,
Ethyl ene Oxide
Pol yvinyl chloride
and NBR
Tires
Hoses, Seals,
Gaskets
Seals, Gaskets, 0-Rings
Wire Insulation
Source: Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limitations
Guidelines and New Source Performance Standards for the Tire and
Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D. C., 1974.
Handbook of Plastics and Elastomers. Charles A. Harper, ed.
N.Y., McGraw-Hill, 1975.
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specialty rubbers such as polyurethane tend to be spread out over the United
States so as to be near specific consumers.
Table 5 lists the six largest companies, their primary products, and pro-
duction capacities along with the collective capacity of the other 62 companies.
A complete list of all plants, by company, is given in Table C-l of Appendix C.
Production capacities were not available for many of the plants which produce
low-volume specialty rubbers.
Table 5. CAPACITY OF SIX LARGEST SYNTHETIC RUBBER PRODUCERS
Company
Goodyear Tire and Rubber
Firestone Tire and Rubber
B. F. Goodrich
E. I. duPont de Nemours
Exxon Corporation
Phillips Petroleum
All Others
Number of
Plants
10
8
18
9
4
2
94
TOTAL
Capacity*
(Gg/Yr)
690
515
367
253
199
196
780b
3000b
Major Products
SBR
SBR
SBR
CR,
EPM
SBR
, BR,
, BR,
, BR,
EPT,
, EPT
, BR
IR, NBR
NBR
IR
CSM
, IIR
aCapacity data was found only for major product lines.
"Estimated
Source: Federal Energy Administration. Report to Congress on Petrochemicals.
Washington, D.C., GPO, undated, circa 1974.
Stanford Research Institute. Directory of Chemical Producers, USA.
Menlo Park, California, 1976.
Environmental Impact
The synthetic rubber industry produces all three types of waste (gaseous
solid, and liquid) in varying degrees. The largest source of pollution is
aqueous emissions. Paramters of interest in characterizing liquid waste
streams include biological oxygen demand (BOD) chemical oxygen demand (COD),
total suspended solids (TSS), and total dissolved solids (TDS). The petro-
chemical feedstocks used as raw materials may be emitted in low concentrations
in wastewater, as fugitivie gaseous emissions, or in solid residues. Other
materials which may be emitted during the manufacturing process include all
of the catalysts, initiators, modifiers, etc. which are added in small quanti-
ties in various processes. Table 6 lists some organic chemicals which were
identified in aqueous waste streams from some synthetic rubber plants.
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Fugitive emissions of gaseous organic compounds are possible from virtually
all of the processes associated with the industry. Information was not avail-
able on the quantity of vapors emitted. Other gaseous emissions arise from
solvent and monomer recovery processes and from drying of the rubber product.
A possible link is being investigated between contact with organic vapors such
as benzene, butadiene, and styrene encountered in synthetic rubber production
plants and reported cases of cancer. Cases of lymphosarcoma have been re-
ported in SBR production workers.
Solid wastes are present primarily as suspended solids (SS) in plant
waste streams. Rubber solids collect on much of the process equipment and are
either removed by hand or washed with water and then added to the general
plant waste stream. Water effluents can be categorized into three types of
wastes. They are: 1) utility wastes such as cooling tower blowdown,
2) process waste streams such as the decant water from solvent separators, and
3) equipment and area washdowns. Some plants purchase their steam while
others generate it on site. Process waste streams and equipment cleanup
wastes are usually combined to give a single plant effluent stream. Tables 7,
8, and 9 present some data for various pollution parameters for the three
operations used in the synthetic rubber industry. The high COD to BOD ratio
is indicative of the resistance of the stream to treatment by biological
oxidation. Most plants have some in-plant control technology. The major
control problems are reduction of the COD and total suspended solids (TSS) to
levels which are amenable to treatment by secondary treatment plants. Table
10 summarizes the control practices and levels reached by some synthetic rubber
plants.
EPA Source Classification Codes for the synthetic rubber industry are
summarized in Table 11.
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Table 6. ORGANIC COMPOUNDS IDENTIFIED IN EFFLUENTS FROM SYNTHETIC RUBBER PLANTS
Compound
Waste Stream
Concentration (mg/£)
00
2-Benzothiazole
2-Benzothiazole
n-Butylisothiocyanate
bis-(2-Chloroethoxy)
methane
bis-2-Chloroethyl ether
Dibutyl amine
N,N-Di ethylformami de
Diethylphthalate
Dimethylphthalate
p-Dithiane
Ethyl isothiocyanate
Furfural
Latex accelerators and thickeners 0.16
plant's holding pond
Synthetic rubber plant's aerated NA
1agoon.
Latex accelerators and thickeners 0.1
holding pond
Synthetic rubber plant's treated 140
waste
Synthetic rubber plant's treated 0.16
waste
Latex accelerators and thickeners <1
plant's raw effluent
Latex accelerators and thickeners <1
plant's raw effluent
Synthetic rubber plant's settling NA
pond
Synthetic rubber plant's settling pond NA
Synthetic rubber plant's treated waste 0.12
Latex accelerators and thickeners <1.5
plant's raw effluent
Synthetic rubber plant's settling 0.002
pond
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Table 6. ORGANIC COMPOUNDS IDENTIFIED IN EFFLUENTS FROM SYNTHETIC RUBBER PLANTS
Compound
Waste Stream
Concentration (mg/&)
2-Mercaptobenzothi azole
1-Methyl naphthalene
Pentach1orophenol
Styrene
2,2'-Thiodiethanol
(Thiodiglycol)
Triethyl urea
Synthetic rubber plant's aerated
lagoon
Synthetic rubber plant's settling
pond
Latex accelerators and thickeners
plant's holding pond.
Synthetic rubber plant's settling
pond
Synthetic rubber plant's treated
waste
Latex accelerators and thickeners
plant's raw effluent
NA
0.002
0.4
0.003
2(E)
6.4
Notes: NA - not available
E - Estimated
Source: Webb, Ronald G., et al. Current Practice in GC-MS Analysis of Organics in Water.
EPA-R2-73-277. 16020 GHP. Athens, Ga., EPA, Southeast Environmental Research
Lab., 1973.
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Table 7. RAW WASTE LOADS FOR SOME EMULSION CRUMB RUBBER PLANTS3
Plant
A
B
B
C
C
C
Median
Product
SBR and NBR Part
Oil and Carbon Black
Extended
SBR Part Oil
Extended
SBR Oil Extended
SBR Oil and Carbon
Black Extended
SBR "Hot", Non-
Extended
SBR Non-Extended
Value
Flow (m3/kg
of Product)
15,000
18,500
18,500
16,500
15,500
15,500
16,600
COD (g/kg
of Product)
11.98
22.23
19.76
8.72
29.24
25.87
19.63
BOD (g/kg
of Product)
N.A.
2.13
2.13
2.84
2.84
2.84
2.56
SSb (g/kg
of Product)
3.73
2.30
11.31
3.94
N.A.
11.94
6.64
Oil (g/kg
of Product)
2.09
0.13
3.54
0.48
1.31
1.45
1.5
^Includes utility wastewaters.
"Raw waste load determined downstream of crumb pits, where the suspended solids and oil levels are
reduced.
NA = Data not available
Source: Medley, W. H., et al. Potential Pollutants from Petrochemical Processes, final report. Contract
68-02-0226, Task 9, MRC-DA-406. Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
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Table 8. RAW WASTE LOADS FOR SOME SOLUTION CRUMB RUBBER PLANTS
Plant
B
B
C
C
D
E
E
F
Medi an
Product
SBR Oil Extended
SBR Carbon Black Ex-
tended
PBR Oil Extended
SBR Non-Extended
PBR Non- Extended
IR Non-Extended
PBR Part Oil Extended
PBR, IR EPDM
Part Oil and Carbon
Black Extended
Value
Flow (m3/kg
of Product)
10,500
17,800
28,500
14,700
3,400
11,900
11,900
29,000
16,000
COD (g/kg
of Product)
4.04
20.80
18.40
13.28
0.17
3.61
3.01
5.33
9.03
BOD (g/kg
of Product)
0.09
0.18
1.55
0.82
0.06
1.37
1.37
3.57
1.13
SSa (g/kg
of Product)
0.81
2.20
5.72
1.79
0.05
NA
5.37
3.71
2.81
Oil (g/kg
of Product)
NA
NA
2.43
1.43
0.07
0.01
2.32
0.23
1.08
aRaw waste load determined downstream of crumb pits, where the suspended solids and oil levels are
reduced.
NA = Data not available.
Source: Medley, W. H., et al. Potential Pollutants from Petrochemical Processes, final report. Contract
68-02-0226, Task 9, MRC-DA-406. Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
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Table 9. RAW WASTE LOADS FOR SOME LATEX RUBBER PLANTS
ro
Plant Product
G SBR and NBR
H SBR
Average Value
Flow (m3/kg
of Product)
14,900 (1,790)
12,000 (1,500)
13*500
COD (g/kg
of Product)
36.37
33.52
34.95
BOD (g/kg
of Product)
5.61
5.01
5.31
SS (g/kg
of Product)
6.70
5.63
6.17
Oil (g/kg
of Product)
NA
0.33
0.33
NA = Data not available.
Source: Hedley, W. H., et al. Potential Pollutants from Petrochemical Processes, final report. Contract
68-02-0226, Task 9, MRC-DA-406. Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
-------
Table 10. CHARACTERISTICS OF TREATED EFFLUENTS FROM SYNTHETIC RUBBER PRODUCTION PROCESSES
Plant Product Process
A Crumb
Crumb
B Crumb
C Crumb
Crumb
SBR
Crumb
Crumb
D Crumb
SBR
NBR
SBR
SBR
, hot
PBR
SBR
PBR
Emulsion
Solution
Emulsion
Emulsion
Emulsion
Solution
Solution
Solution
Production
Capacity
(Metric Control
ton/yr) Measures
290
10
130
200
120
3
52
10
85
,000
,000
,000
,000
,000
,700
,000
,000
,000
Crumb
Carbon
Pits
Crumb
Carbon
Pits
Crumb
Crumb
Pits,
Slurry
Pits,
Slurry
Pits
Pit, Dry
Primary Effluent
Treatment
Chemical
and Clari
Coagulation
fi cation
Air Flotation
Primary Clarifica-
tion
Chemical
and Settl
Coagulation
ing Ponds
Oil Separator
Ef f 1 uent
Concentrations
Secondary Effluent (y§/m3)
Treatment BOD COD TSS
Aeration,
and Stabi
Lagoons
Settling 25 325
lization
Aerated Lagoon and NAa NA
30
NA
Air Flotation
Secondary
tion
Aeration
and Stabi
Ponds
None
Clarifica-
Lagoon NAb NA
lization
NA NA
NA
NA
Desolventizing
Process, Spent
Causti
c Pit with
Slow Bleed Dis-
E - Crumb
Crumb
F Crumb
Crumb
Crumb
G Latex
Latex
IR
PBR
PBR
IR
EPDM
SBR
NBR
Solution
Solution
Solution
Solution
Solution
Emulsion
Emulsion
65
110
56
50
25
18
3
,000
,000
,000
,000
,000
,000
,000
charge
Crumb
Crumb
Carbon
Pit
Excess
Decant
Pits
Pits,
Slurry
Monomer
System
Equalization
Basin
Settling
Lagoons
Coagulation and
Settling
Pit
Activated
Sludge 10 250
Stabilization 5 50
Lagoon
Activated
SI udge 50 600
NA
NA
NA
-------
Table 10. CHARACTERISTICS OF TREATED EFFLUENTS FROM SYNTHETIC RUBBER PRODUCTION PROCESSES (Continued)
Production
Capacity
(Metric
Plant Product Process ton/yr)
Q Latex SBR Emulsion 21,000
Control
Measures
Excess Monomer
Decant System
Primary Effluent
Treatment
Chemical Coagulation
and Clarification
Effluent
Concentrations
Secondary Effluent (yg/m3)
Treatment
Discharge to a
Municipal Sewage
Treatment Plant
BOD COD TSS
NAC NA NA
fHigh quality effluent produced. TSS and COD still present at substantial levels.
DBOD exceeds State requirements.
CCOD and BOD levels reduced 70% and 50% respectively.
NA = Data not available.
Source: Hedley, W. H., et al. Potential Pollutents from Petrochemical Processes, final report. Contract
68-02-0226, Task 9, MRC-DA-406. Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
-------
TABLE 11. SOURCE CLASSIFICATION CODES FOR SYNTHETIC RUBBER
Operation Code
Butadiene-General 3-01-026-01
Methylpropene-General 3-01-026-02
Butyne General 3-01-026-03
Pentadiene General 3-01-026-04
Cimethheptane General 3-01-026-05
Pentane-General 3-01-026-06
Ethanenitrile General 3-01-026-07
Acrylonitrile General 3-01-026-08
Acrolein General 3-01-026-09
Other/Not Classified 3-01-026-99
15
-------
Bibliography
1 Billmeyer, Fred W., Jr. Textbook of Polymer Science, 2nd Ed. N.Y., Wiley,
1971.
2. Cooper, W. Elastomers, Synthetic. In: Encyclopedia of Polymer Science
and Technology, Vol 5. H. F. Mark, ed, N.Y., Wiley, 1966, pp 406-82.
3. Environmental Aspects of Chemical Use in Rubber Processing Operations
(March 12-14, 1975, Akron, Ohio). Conference Proceedings. Office of
Toxic Substances, EPA, Washington, D.C. Franklin A. Ayer, Compiler.
May 1975.
4. Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limitations
Guidelines and New Source Performance Standards for the Tire and
Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D.C., 1974.
5. Federal Energy Administration. Report to Congress on Petrochemicals.
Washington, D.C., GPO, undated, circa 1974.
6. Gerstle, R. W. Industrial Process Profiles for Environmental Use,
Vol 1., 1st Ed. Terry Parsons, ed. EPA Report 600/2-76-051 a.
7. Handbook of Plastics and Elastomers. Charles A. Harper, ed. N.Y.,
McGraw-Hill, 1975.
8. Hargreaves, C. A.', II and D. C. Thompson. Elastomers, Synthetic. In:
Kirk-Othmer Encyclopedia of Chemical Technology, Vol 7. Anthony Standen,
ed. N.Y., Wiley, 1968, pp. 676-716.
9. Meyer, Glen E. Elastomers. In: Chemical and Process Technology
Encyclopedia. Douglas M. Considine, ed. N.Y., McGraw-Hill, 1974,
pp. 387-94.
10. NIOSH Seeking Industry's Help In Check of SBR-Leukemia Link. Chemical
Marketing Reporter, 209(19):!!, May 10, 1976.
11. Production Fell, Often Sharply, Last Year for Almost all Major Chemical
Products. C&EN 54(74):37, June 7, 1976.
12. Rubber Industry: Growth Despite Problems. C&EN 54(16):11, April 12, 1976.
13. Rubber Technology and Manufacture. Claude M. Blow, ed. London, Butterworths,
1971.
14. Stanford Research Institute, Directory of Chemical Producers, USA. Menlo
Park, California, 1976.
15. Synthetic Rubber. George S. Whitby, ed. N.Y,, Wiley, 1954.
16
-------
15. Synthetic Rubber Makers See Good Second Half, Strong 1976. C&EN 53(36):11-2,
Sept. 8, 1975.
17. The Applied Science of Rubber. W. 0. S. Naunton, ed. London, Edward
Arnold (Publishers) Ltd., 1961.
18. U. S. Department of Commerce, Bureau of the Census. 1972 Census of Manu-
facturers, Plastics Materials, Synthetic Rubber, and Man-made Fibers.
November 1974.
13. United States International Trade Commission. Synthetic Organic Chemicals,
United States Production and Sales, 1973. ITC Publication 728. Washington,
1975.
20. Webb, Ronald G., et al. Current Practice in GC-MS Analysis of Organics in
Water. EPA-R2-73-277. 16020 GHP. Athens, Ga., EPA, Southeast Environmental
Research Lab., 1973.
17
-------
INDUSTRY ANALYSIS
The Synthetic Rubber Industry is described by three operations composed of
related processes. These three operations are responsible for 98 percent of
elastomer production. These operations are Emulsion Crumb Production, Latex
Production, and Solution Crumb Production.
Each operation is described by a flow sheet indicating input materials
(brackets), processes (numbered rectangles), and product streams (large cir-
cles). Solid, liquid and gaseous waste streams are indicated by the small
squares, triangles and circles, respectively, attached to the numbered pro-
cess rectangles. Process descriptions follow the flow sheets on which they
are presented.
Data are given in metric units according to the System Internationale
described in the ASTM Metric Practice Guide. Preferred base units and rules
for rounding numbers converted from one system of units to another are de-
scribed therein.
The information used to prepare this catalog entry consisted of books,
encyclopedias, results of EPA supported investigations, and several recently
published trade journal articles. There are additional sources of informa-
tion such as the open literature, patent literature, and publications of
Stanford Research Institute's Process Economics Program which were not
utilized because of the limited resources available for this study. The
reader is advised to consult these additional sources of information on
subjects which were not treated in depth.
Most of the process information was obtained from a comprehensive text
published in 1954. The process information given in this text has reappeared
in several recent reports and was therefore considered currently practicable.
It should be noted, however, that discrepancies between process descriptions
and actual practice may occur.
18
-------
EMULSION CRUMB PRODUCTION PROCESSES
This segment of the Synthetic Rubber Industry is composed of processes which
produce crumb rubber by emulsion polymerization. Most of the processes are
run on a continuous or batch-continuous basis around the clock, 365 days a
year.
Feedstocks for the tire rubbers produced in this operation and the
corresponding synthetic rubber products are summarized in Table 12. Some
waste stream data for emulsion crumb production plants are given in Table 13.
Data for utilities for individual processes are generally unavailable.
Table 12. MAOOR FEEDSTOCKS AND PRODUCTS FOR EMULSION CRUMB PRODUCTION
Feedstock Elastomer
Styrene, butadiene SBR
Acrylonltrile, butadiene NBR
Chloroprene CR
Ethylene, propylene EPM, EPDM
Table 13. RAW WASTE LOADS FOR SOME CRUMB RUBBER PLANTS3
Product Flow (mVkg) COD (g/kg) BOD (g/kg) SS (g/kg)
SBR and NBR 15,000 11.98 NA 3.73
Part Oil & Carbon
Black Extended
SBR 18,500 22.23 2.13 2.30
Part Oil Extended
SBR 18,500 19.76 2.13 11.31
011 Extended
SBR 16,500 8.72 2.84 3.94
011 and Carbon
Black Extended
SBR 15,500 29.24 2.84 NA
"HOT" Non-Extended
SBR 15,500 25.87 2.84 11.94
Non-Extended
Median 16,500 19.63 2.56 6.64
Oil (g/kg)
2.09
0.13
3.54
0.48
1.31
1.45
1.5
"Includes utility wastewaters
"Determined downstream of crumb pits
Source: Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limitations
Guidelines and New Source Performance Standards for the Tire and
Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D. C., 1974.
19
-------
Figure 1 is a flow sheet for this operation. The processess are:
1) Monomer Storage, 2) Caustic Wash, 3) Polymerization, 4) Light Monomer
Recovery, 5) Heavy Monomer Recovery, 6) Coagulation and Screening, and
7) Crumb Washing, Drying, and Finishing.
Most of the data which were available were for the production of styrene-
butadiene rubber (SBR). Thus, the process descriptions generally pertain to
the production of SBR with data for the other products whenever possible.
Processes 1 and 2 are included with emulsion crumb production because
more information was available, although these processes appear to be the
same for both latex and solution crumb production. Process descriptions
will not be repeated in those two operations.
20
-------
INHIBITED
MONOMER
ro
LEGEND
QGASEOUS EMISSIONS
Q SOLID EMISSIONS
A LIQUID EMISSIONS
ACTIVATOR
CATALYST
MODIFIER .SHORT
LIGHT
MONOMER
SEPARATION 4
TO LATEX PRODUCTION
• J
TO SOLUTION CRUMB!
PRODUCTION j
ACID BRINE
COAGULATING
/EXTENDER OIL
/CARBON BLACK
^^
s
J
COAGULATION
AND
SCREENING „
6
i
STEAM
\ '
/RECY
IMONO
L t£
S-r-t
1 HEAVY MONOMER
' SEPARATION g
WATER
OVERFLOW
FIGURE 1 . PROCESS DIAGRAM FOR EMULSION CRUMB OPERATION
-------
EMULSION CRUMB PRODUCTION PROCESS NO. 1
Monomer Storage
1. Function - Monomers used for elastomer production are either piped or
tanked into elastomer plants and stored in tank farms. Low-boiling monomers
such as butadiene must be stored in pressure vessels containing safety valves
which discharge to a flare. Inhibitors are usually added by the monomer pro-
ducing plants to prevent premature polymerization during shipment or storage.
The storage tanks are generally provided with auxiliary equipment for the
addition of extra inhibitor by the elastomer producer. The tank farm is diked
to minimize the spread of fire or spills.
The monomer storage process is common to all three operations in the
synthetic rubber industry. This process description could apply equally to
monomer storage in either latex or solution crumb production.
2. Input Materials - Various tanks are designated for storage of fresh, re-
cycled, or blended monomer. Raw materials typically stored for use by elastomer
producers are given in Table 14.
Table 15 gives the concentration of inhibitors used for storage of SBR-
producing monomers.
Table 14. MAJOR RAW MATERIALS USED AS MONOMERS
Monomer Products
Butadiene SBR, BR, NBR
Styrene SBR
Acrylonitrile NBR
Chloroprene CR
Ethylene EPM, EPDM
Propylene EPM, EPDM
Isoprene HR. IR
Isobutylene IIR
Table 15. INHIBITOR CONCENTRATIONS FOR STORAGE OF STYRENE MD BUTADIENE
Monomer Inhibitor Concentration, yg/nr
Butadiene p-tert-butylcalechol (TBC) 200
Styrene TBC 1 10
22
-------
3. Operating Parameters - Monomers are stored in 100 m3 horizontal steel
tanks or, in the case of butadiene, in Horton spheres,
4- Utilities - No data were available in the sources consulted in this study.
5. Waste Streams - Gaseous emissions of volatile species such as butadiene
are possible but should be adequately controlled by the pressure relief system.
Spillage or leaks of liquid raw materials could occur but are only of minor
interest because of the dike system.
6. EPA Source Classification Code - See Table 11.
7. References -
1) Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limitations
Guidelines and New Source Performance Standards for the Tire and
Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D. C., 1974.
2) Synthetic Rubber. George S. Whitby, ed. N.Y., Wiley, 1954.
23
-------
EMULSION CRUMB PRODUCTION PROCESS NO. 2
Caustic Wash
1. Function - The inhibited monomer from storage must be treated to lower the
inhibitor concentration to a level which will allow polymerization to occur.
The inhibitor concentration in monomers such as styrene is low enough to permit
the inhibited monomer to be used directly. Easily polymerized monomers such
as butadiene, however, require a scrubbing with a caustic wash to decrease the
inhibitor to polymerizable levels. The inhibitor is removed by washing the raw
monomer with a caustic solution in a contactor packed with Raschig rings,
followed by decantation. The uninhibited monomer is blended with recovered,
lower purity monomer from either Process 4 or Process 5 to give the correct
purity for further processing. After blending, the combined stream is
charged to the polymerization reactors (Process 3).
2. Input Materials - Although input materials could be any of the monomers
listed in Table 14 in Process 1, compositional information was found only
for butadiene. The inhibited butadiene contains 200 yg/m3 of TBC prior to
caustic wash treatment. The caustic solution typically contains 20 percent
sodium hydroxide by weight. The butadiene blend is usually greater than
95% pure after being washed.
3. Operating Parameters - No information was available in the sources consulted.
4. Utilities - No data were available in the sources consulted in this study.
5. Waste Streams - This process produces a liquid waste stream consisting of
spent caustic and removed inhibitor. This stream has very high COD, alkalinity,
pH, and color characteristics and contains phenols. The spent caustic is us-
ually recycled until it becomes saturated with inhibitor and is then discharged
into a pit. From this pit the solution is slowly discharged into the total
plant effluent stream of a flow rate less than 0.25 m3/h.
One value for the quantity of sodium hydroxide emitted in the caustic wash-
ing of isoprene in the production of polyisoprene was 0.1 g/kg product. One
study reported that a plant producing 21,000 kg/hour of SBR generates a waste
stream containing a COD of 28 mg/m3 with total alkalinity of 72 mg/m3. It was
also reported that the production of BR by solution polymerization (13,000 kg/hour)
produced a caustic inhibitor effluent containing a COD of 98 mg/m3.
6. EPA Source Classification Code - See Table 11.
7. References -
1) Environmental Aspects of Chemical Use in Rubber Processing Operations
(March 12-14, 1975, Akron, Ohio). Conference Proceedings Office of
Toxic Substances, EPA, Washington, D. C. Franklin A. Ayer, Compiler.
May 1975.
24
-------
2) Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limitations
Guidelines and New Source Performance Standards for the Tire and
Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D. C., 1974.
3) Medley, W. H,, et al. Potential Pollutants from Petrochemical
Processes, final report. Contract 68-02-0226, Task 9, MRC-DA-406.
Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
4) Synthetic Rubber. George S. Whitby, ed. N.Y., Wiley, 1954.
25
-------
EMULSION CRUMB PRODUCTION PROCESS NO. 3
Polymerization
1. Function - This process is used to connect the raw monomers containing
soap, catalyst, activator, and modifer into an aqueous dispersion of poly-
merized rubber solution called a latex. The polymerization occurs in
emulsifier micelles formed by dispersing the monomers into a soap solution.
Catalysts, activators, and modifiers are used to initiate and control the
reaction. Further reaction control is accomplished by careful regulation
of the reaction temperature within plus or minus 0.25°C using either cooling
coils containing ammonia refrigerant, chilled water, chilled brine or steam.
Polymerization occurs in a series of reactors, any of which can be by-
passed if desired. Two forms of SBR are produced and are designated either
"hot" or "cold." The reaction is usually terminated at around 60 percent
conversion for "cold " SBR by the addition of chemicals called "shortstops."
Hot SBR is shortstopped at 72 percent conversion. The shortstop solution is
added whenever analysis of the reaction mixture indicates the correct polymer
composition.
Polymerization is carried out on a continuous or batch-continuous basis
with the input charge carefully metered according to standard formulations
called recipes. Each batch of latex produced is stored in one of several
storage tanks where it may be blended with other batches to give a more uniform
product. The blended latex still contains large amounts of monomer as well as
other additives. Recovery of unreacted monomers is accomplished in the next
two processes.
2. Input Materials - Input materials for this process include the monomers
from either Caustic Wash (Process 2) or Monomer Storage (Process 1) as well
as a variety of catalysts, modifiers, activators and soaps. Shortstops are
added later in the process. Some recipes for various elastomers produced by
emulsion polymerization are given in Table A-7 in Appendix A. The water used
in the preparation of these solutions is generally deionized city or well water.
Emulsifiers used in emulsion polymerization are generally alkali salts of
organic carboxylic acids with chain lengths between C12 and C18 (soaps) and
disproportionated rosin soaps. Sodium soaps are most frequently used although
potassium soaps are used in some lower temperature polymerizations. Initiators
are added to produce an active free radical either by thermal decomposition or
or chemical reaction. The most common initiators are based on organic peroxides
or inorganic peroxydisulfates. Activators such as sodium dithionite assist in
the formation of free radicals by consuming oxygen. Modifiers such as dode-
canethiol function as chain-transfer agents which assist in producing a more
desirable product. Shortstops include materials such as sodium dithiocarbamate
and are used to stop the reaction at the desired conversion. Antioxidants
may be added to protect the rubber product. Lists of these additives are
found in Appendix A.
26
-------
3. Operating Parameters - A typical reactor system consists of a series of
glass-lined steel vessels equipped with modified Brumagin-type agitators
rotating 105 rpm. A typical reactor has a capacity of 14 m3 and is designed
to withstand a pressure of 860 kPa (125 psig). The addition of each bath of
ingredients is carefully metered using separate pumps with the catatlysts
added last. A typical charge is 10,000 kg.
Control of the reaction temperature is very critical in producing the
desired polymer. For production of hot SBR the reaction must be controlled
within plus or minus 0.25°C. The initial pressure in the reactor is around
500 kPa (60 psig). This pressure drops to about 375 kPa (45 psig) as the
reaction progresses. Table 16 summarizes the operating parameters for this
process. Feed streams are generally cooled to the reactor temperature before
entering the reactor. A 27 Gg annual capacity plant requires a 725 Mg capacity
of -18°C refrigeration for the production of cold SBR.
Table 16. OPERATING PARAMETERS FOR POLYMERIZATION
Reactor Temperature Reactor Pressure
Product
Hot SBR
Cold SBR
NBR
CR
(°c)
50
4 to 7
33 to 35
40
(kPa)
375 to 515
100 to 205
800 to 900
-
% Conversion
72
60
-
-
Source: The Applied Science of Rubber. W. J. S. Naunton, ed. London,
Edward Arnold (Publishers) Ltd., 1961.
4- Utilities - Data on utilities were not found in the sources consulted
for this study.
5. Waste Streams - There are no waste streams directly associated with this
process. Fugitive emissions from valves, seals, etc. could release hazardous
organic vapors such as butadiene, styrene, or acrylonitrile.
Cleanup of the reactors requires occasional usage of large volumes of
rinse water. This rinse water contains dissolved organics and suspended solids
and is sent to waste treatment.
Cooling-tower waste waters associated with this process characteristically
have high total dissolved solids and moderate COD, suspended solids, and pH.
Corrosion inhibitors containing zinc and chromium are also present.
27
-------
6. EPA Source Classification Code - See Table 11.
7. References -
1) Billmeyer, Fred W., Jr. Textbook of Polymer Science, 2nd Ed. N.Y.,
Wiley, 1971.
2) Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limitations
Guidelines and New Source Performance Standards for the Tire and
Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D. C., 1974.
3) Hedley, W. H., et al. Potential Pollutants from Petrochemical Processes,
final report. Contract 68-02-0226, Task 9, MRC-DA-406. Dayton, Ohio,
Monsanto Research Corp., Dayton Lab., Dec. 1973.
4) Sittig, Marshall. Pollution Control in the Plastics and Rubber Indust.
Park Ridge, N.J., Noyes Data Corp., 1975.
5) Synthetic Rubber. George S. Whitby, ed. N.Y., Wiley, 1954.
6) The Applied Science of Rubber. W. J. S. Naunton, ed. London, Edward
Arnold (Publishers) Ltd., 1961.
28
-------
EMULSION CRUMB PRODUCTION PROCESS NO. 4
Light Monomer Recovery
1. Function - For most plants, monomer recovery is divided into two sections.
The function of this process is to recover light (low-boiling) monomer while
Process 5 is used for heavy (higher-boiling) monomer recovery. For SBR and
NBR production the light monomer, butadiene, is recovered by stripping the
latex from Process 3 in a vacuum flash tank. The stripped butadiene vapors
are then compressed and discharged into a vertical tube condenser. The buta-
diene vapor passes through an oil-absorption column which traps residual
noncondensible impurities. These impurities are vented to the flare. The
condensed butadiene is pumped to feed tanks in the monomer storage area for the
preparation of blends. In some cases the recovered butadiene is tanked to a
butadiene purification plant before being used. The partially stripped latex
is then pumped to Process 5 for further monomer stripping.
2. Input Materials - The input material to this process is the unstripped
latex from Process 3. Table 17 gives the composition of a hot SBR latex before
monomer recovery.
Table 17. COMPOSITION OF LATEX BEFORE MONOMER RECOVERY
Parts per 100
Parts Total Monomer
Component Charged by Weight
Water 185
Butadiene in polymer 55.1
Styrene in polymer 16.9
Unreacted Butadiene 15.9
Unreacted Styrene 12.1
Soap 4.3
Impurities 4.8
Catalyst, Activators, Shortstops 0.8
TOTAL 294.9
Source: Synthetic Rubber. George S. Whitby, ed. N.Y., Wiley, 1954.
29
-------
3. Operating Parameters - The latex is continuously feed to two flash tanks
at .150 to .230 m3/min where the butadiene is vaporized by reducing the pressure
from 375 to 122 kPa (30 to 3 psig) in the first tank and then to 30 kPa (220 mm
mercury) in the second. Glasslined horizontal cylindrical vessels with 38 m3
capacity are used for the flash tanks. The vapors are compressed using water-
sealed Nash-type rotary vacuum pumps and discharged into the condenser at 515
kPa (60 psig) and 55°C. A 0.5% by weight sodium nitrate solution is used by
the pumps to compress the vapors.
4. Utilities - No data were available in the sources consulted for this study.
5. Waste Streams - A liquid waste stream from this process results from fre-
quent equipment cleanup. Large volumes of water are used for this cleaning
operation generating a waste stream high in COD and suspended solids. Table
18 summarizes liquid waste stream data for monomer recovery for SBR production.
Table 18. RAW WASTE LOADS FROM MONOMER RECOVERY PROCESSES3
Concentration Total Plant Load
Parameter
COD
BOD
SS
TDS
Oil
Surfactants
(g/kg of Product)
0.66
0.14
0.08
1.26
0.11
0.0001
(g/kg of Product)
19.6
2.6
6.6
NA
1.5
NA
Includes both heavy and light monomer recovery
Source: Environmental Protection Agency, Office of Air and Water
Programs, Effluent Guidelines Div. Development Document
for Effluent Limitations Guidelines and New Source Per-
formance Standards for the Tire and Synthetic Segment of
the Rubber Processing Point Source Category. EPA 440/1-
74-013-a. Washington, D. C., 1974.
At most plants this waste stream is passed through settling ponds to separate
the rubber solids and floating oils before being sent to waste treatment.
Fugitive emissions from valves, seals, etc. could release hazardous organic
vapors. Other gaseous emissions could arise from burning of the residual non-
condensibles in flares.
30
-------
Cooling-tower waste waters ape also associated with this process. These
waste waters characteristically have high total dissolved solids and moderate
COD, suspended solids, and pH. Corrosion inhibitors containing zinc and chrom-
ium are also present.
6. EPA Source Classification Code - See Table 11.
7. References -
1) Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limitations
Guidelines and New Source Performance Standards for the Tire and
Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D. C., 1974.
2) Medley, W. H., et al. Potential Pollutants from Petrochemical
Processes, final report. Contract 68-02-0226, Task 9, MRC-DA-406.
Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
3) Synthetic Rubber. George S. Whitby, ed. N.Y., Wiley, 1954.
31
-------
EMULSION CRUMB PRODUCTION PROCESS NO. 5
Heavy Monomer Recovery
1. Function - As in Process 4 this process recovers unreacted monomer from
the latex. Heavy monomers such as styrene and acrylonitrile are removed using
low-pressure steam stripping in a perforated plate column. The steam-monomer
mixture is then sent to a receiver where the vapors are condensed and the
phases separated by gravity. The top organic layer is recycled into the
monomer feed supply system while the water is discharged to waste treatment.
The monomer-stripped latex is sent to a blend tank where it is stabilized by
the addition of an antioxidant. The stabilized latex may then be blended with
other latices before further processing.
2. Input Materials - Input materials are butadiene-stripped latex from
Process 4 and steam. Antioxidants include amino and phenolic compounds such
as those listed in Table A-5 in Appendix A.
3. Operating Parameters - Steam stripping columns used for SBR production
are 2.7 m in diameter and 15 m high. The columns contain 12 perforated porcelain-
enameled No. 11 gage Armco iron trays with 0.5-cm holes on a 1.6-cm triangular
pitch. Steam injection occurs at 60°C. Adjustable weirs are used to maintain
7.6 cm of latex on the trays. The column pressure ranges from 8 to 13 kPa at
the top to 13 to 20 kPa at the bottom.
Removal of acrylonitrile requires two stripping towers because of the
toxicity of low levels of residual acrylonitrile. Styrene-stripped latex
contains only 0.2% residual styrene.
4. Utilities - Information was generally unavailable. Steam is generated
on site by some facilities.
5. Waste Streams - Aqueous waste streams result from cleanup of equipment
and from discharge of the condensed and separated water used for steam stripping.
Effluent load data are given in Table 18 under Process 4 for monomer recovery
processes.
Fugitive atmospheric emissions of harzardous organic vapors are potentially
present because of leaks in the system.
Cooling tower waste waters associated with this process characteristically
have high total dissolved solids and moderate COD, suspended solids, and pH.
Corrosion inhibitors containing zinc and chromium are also present.
6. EPA Source Classification Code - See Table 11.
7. References -
(1) Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limita-
tions Guidelines and New Source Performance Standards for the Tire
and Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D. C., 1974.
32
-------
(2) Medley, W. H., et al. Potential Pollutants from Petrochemical
Processes, final report. Contract 68-02-0226, Task 9, MRC-DA-406.
Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
(3) Synthetic Rubber. George S. Whitby, ed. N. Y., Wiley, 1954.
33
-------
EMULSION CRUMB PRODUCTION PROCESS NO. 6
Coagulation and Screening
1. Function - This process serves to coagulate the dispersed polymer in the
latex and thus permit-separation of the product from the aqueous medium.
This process also includes addition of components (extenders) to improve the
quality of the rubber product.
The latex is coagulated by addition of acid and brine. The brine causes
a "creaming" of the latex which is a partial flocculation of the rubber particles,
causing the consistency of the latex to change from a mobile liquid to a heavy
cream. The addition of dilute sulfuric acid to a pH of 4.0 to 4.5 converts the
soap molecules to organic fatty acids which causes the rubber pacticles to ag-
glomerate. The particles are then separated from the coagulation liquor on a
shaker screen. The liquor is recycled with fresh acid and brine make-up added
as needed. The screened rubber particles are slurried with water and sent to
Process 7.
The addition of hydrocarbon oils (oil extending) improves processing
properties and reduces cost. The addition of carbon black (masterbatching)
to the latex immediately before coagulation produces an elastomer with improved
physical properties such as increased tensile strength, stiffness, abrasion
resistance, and tear resistance. The extender oil is added as an aqueous
emulsion while the carbon black is added as an aqueous slurry.
2. Input Materials - The input materials are latex, brine, acid, extender oil,
and carbon black. Fresh, concentrated (66° Be'.) sulfuric acid and saturated
sodium chloride (26 wt%) is used for make-up of the coagulating liquor.
Carbon black is added as a 5% (by weight) aqueous slurry to give a rubber
consisting of from 30 to 60 parts per weight of carbon black to 100 parts by
weight of polymer. The three types of oil used are naphthenic, aromatic, and
highly aromatic. Oil extenders are added as an aqueous emulsion to give a
rubber containing up to 50 parts of oil per 100 parts of polymer. Lists of
some carbon blacks and oils used by the synthetic rubber industry are found
in Tables A-4 and A-5 in Appendix A.
3. Operating Parameters - No data were available in the sources consulted.
4. Utilities - No data were available in the sources consulted for this
study.
5. Haste Streams - Coagulation liquor overflow (blowdown) is a significant
liquid waste stream in the Emulsion Crumb Production processes. Waste stream
data for this effluent, as compared to the total plant waste load, are given
in Table 19. One source indicated that a SBR plant producing 21,000 kg/hour
would have a coagulation overflow effluent with a flow rate of 1 m3/min.
34
-------
Table 19. WASTE LOAD FOR COAGULATION LIQUOR OVERFLOW FOR EMULSION
CRUMB PRODUCTION
Coagulation Liquor Overflow Total Plant Effluent3
Parameter (g/kg product) (g/kg product)
COD 1.30 19.6
TDS 46.25 NA
Oil 0.10 1.5
a
Includes utility wastewater
NA = data not available
Source: Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limitations
Guidelines and New Source Performance Standards for the Tire and
Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D. C., 1974.
Cleanup of coagulation equipment increases waste load in the form of
COD, oil, and suspended solids. Processes which include carbon black master-
batching have a liquid effluent resulting from preparation of the carbon
black slurry. This waste stream passes through settling pits where the
suspended carbon black particles settle out.
6. EPA Source Classification Code - See Table 11.
7. References -
(1) Billmeyer, Fred W., Jr. Textbook of Polymer Science, 2nd Ed.
N. Y., Wiley, 1971.
(2) Environmental Aspects of Chemical Use in Rubber Processing Opera-
tions (March 12-14, 1975, Akron, Ohio). Conference Proceedings.
Office of Toxic Substances, EPA, Washington, D. C. Franklin A,
Ayer, Compiler. May 1975.
(3) Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limitations
Guidelines and New Source Performance Standards for the Tire and
Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D. C., 1974.
(4) Synthetic Rubber. George S. Whitby, ed. N. Y., Wiley, 1954.
35
-------
EMULSION CRUMB PRODUCTION PROCESS NO. 7
Crumb Washing, Drying, and Finishing
1. Function - This process removes extraneous material from the rubber and
processes the purified rubber into bales which can then be sold or captively
used. The washing process step removes residual coagulation liquor along with
catalysts, emulsifiers, oil, and other contaminants. The rinsed crumb may be
filtered and dewatered in an Oliver rotary vacuum filter. The filtrate is
sent to a reslurry tank where blowdown of some of the wash water occurs. The
remainder of the water is recycled to the crumb washing unit along with fresh
make-up water. The dewatered crumb is dried with hot air in either continuous
or screen dryers, weighed, and formed into 35 kg bales using an hydraulic baler.
The bales are wrapped in polyethylene film before shipment.
2. Input Materials - The input materials to this process are the coagulated
crumb from Process 6 and water.
3. Operating Parameters - The filtered crumb is dried at 82°C for 2 hours
in a continuous dryer.Both oil- and water-driven hydraulic balers are used.
4. Utilities - No data were available in the sources consulted for this
study.
5. Waste Streams - Overflow from the filtrate reslurry tank, termed crumb
slurry overflow, is a liquid effluent containing high suspended and total
dissolved solids and moderate COD. Average waste load data for crumb slurry
overflow as compared to total plant waste load are summarized in Table 20.
Table 20. AVERAGE WASTE LOADS FOR CRUMB RINSE OVERFLOW IN EMULSION
CRUMB PRODUCTION
Crumb Slurry Overflow Total Plant Load3
Parameter (9/kg of product) (g/kg of product)
COD 6.39 19.63
BOD 0.46 2.56
SS 33.44b 6.64C
TDS 42.33 NA
Oil 1.46 1.5
Surfactants .0077 NA
^Includes utility wastewaters
Determined prior to crumb settling pits
Determined after crumb settling pits
NA = Data not available.
36
-------
Source: Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limitations
Guidelines and New Source Performance Standards for the Tire and
Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D. C., 1974.
This waste stream Is passed through separators, called crumb pits,
which trap the floatable crumb rubber. Oil-drfven balers frequently leak
hydraulic fluid which is carried to the crumb settling pit.
Air drying of the rubber could release hazardous organic vapors.
6. EPA Source Classification Code - See Table 11.
7. References -
(1) Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent
Limitations Guidelines and New Source Performance Standards for the
Tire and Synthetic Segment of the Rubber Processing Point Source
Category. EPA 440/1-74-013-a. Washington, D. C,, 1974.
(2) Medley, W. H., et al. Potential Pollutants from Petrochemical
Processes, final report. Contract 68-02-0226, Task 9, MRC-DA-406.
Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
(3) Synthetic Rubber. George S. Whitby, ed, N. Y., Wiley, 1954.
37
-------
Latex Production Processes
This segment of the Synthetic Rubber Industry is composed of processes
which produce latex by emulsion polymerization. Latex production processes
are similar to emulsion crumb production processes except for Coagulation and
Screening (Process 6) and Rinsing, Drying, and Finishing (Process 7). Latex
production involves virtually 100% polymerization of the monomers and thus
monomer recovery processes are not feasible. However, residual monomers must
be removed for stabilization of the rubber product. The input material to
this process is monomer from Process 2. Although elastomers produced by
emulsion polymerization can be marketed either as latex or crumb, only 5 to 10
percent of SBR and 30 percent NBR rubbers are produced as latex.
Figure 2 is a flow diagram for latex production by emulsion polymerization.
Monomer Storage (Process 1) and Caustic Wash (Process 2) processes are virtually
the same for either latex or crumb production and thus are not discussed in
this operation. The processes in latex production are Polymerization (Process
8), Light Monomer Removal (Process 9), Heavy Monomer Removal (Process 10) and
Blending, Storage, and Shipping (Process 11).
As in crumb production, the plants are operated 24 hours a day and 365
days a year. Production runs are generally smaller because latex consumers
have more varying product needs. Data on utilities and operating conditions
were not available for latex production. Table 21 presents some raw waste
load data for latex plants.
Table 21. AVERAGE RAW WASTE LOADS FOR LATEX RUBBER PLANTS
Value
Parameter (g/kg product)
COD 34.95
BOD 5.31
SS 6.17
Oil 0.33
Source: Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent
Limitations Guidelines and New Source Performance Standards for
the Tire and Synthetic Segment of the Rubber Processing Point
Source Category. EPA 440/1-74-013-a. Washington, D. C., 1974.
Tables 22 and 23 list some potentially hazardous componds identified in latex
plant waste waters.
38
-------
Table 22. COMPOUNDS IDENTIFIED IN LATEX PLANT RAW EFFLUENT
Concentration
Compound (yg/m3)
Ethyl isothiocyanate <1.5
Triethyl urea 6.4
N.N-Diethylformamide <1
Dibutyl amine <1
Source: Webb, Ronald G., et al. Current Practice in GC-MS Analysis of Organics
in Water, EPA-R2-73-277. 16020 GHP. Athens, Ga., EPA, Southeast
Environmental Research Lab., 1973.
Table 23. COMPOUNDS IDENTIFIED IN LATEX PLANT HOLDING POND
Concentration
Compound (yg/m3)
Pentachlorophenol 0.4
2-Benzothiazole 0.16
Source: Webb, Ronald G., et al. Current Practice in GC-MS Analysis of Organics
in Water. EPA-R2-73-277. 16020 GHP. Athens, Ga., EPA, Southeast
Environmental Research Lab., 1973.
39
-------
ACTIVATOR
SOAP *•»•«••'»• STEAM
SOLUTION «~ •"— p <-
1 1 1 K Yu ' 1
MONOMER LJ /" "\ L|GHT / X HEAVY
FROM ,._^fc POI YMFI7I7ATION ^M i ATI-V 1 ^^ MnMnMcrn ^^/ i «-rrw 1 ^^ kir«timii-n
^^ rwi.i wcnitrt uwn 9*1 LATEX i ^ MUNUMttf — ^| LATEX r ^* MONOMER
PR 3 8 V / RPMOVAI V / PFMOVAI
^ * X / 8 \^ / tO
WATER
1 LATEX J-*
LpQEND £ T^ «»i«
OQASEOUS EMISSIONS
Q SOLID EMISSIONS
A LIQUID EMISSIONS
1 — 1 .s^ ~*^
— »4 LATEX )
1
BLEN
nSTOI
& SH
/a
LJ
DING
1AGE
PPING n1
Figure 2. LATEX PRODUCTION PROCESSES
-------
LATEX PRODUCTION PROCESS NO. 8
Polymerization
1. Function - As in Process 3, this process connects the raw monomers from
Process 2 into a polymerized rubber dispersion called latex. The reaction
occurs in micelles formed by dispersing the monomers into a soap solution.
Catalysts, activators, and modifiers are also used to initiate and control
the reaction. Latex generally is made by the "cold" process and therefore
requires efficient refrigeration equipment.
As in crumb production, the polymerization occurs in a series of reactors.
In latex production the polymerization is taken essentially to completion
and thus shortstops are not added. Stabilizers are added after polymeriza-
tion is complete, and the latex is then subjected to stripping processes to
remove unreacted monomers (Processes 9 and 10).
2. Input Materials - Styrene, butadiene, and acrylonitrile are the major
raw materials used to produce SBR and NBR latices. The emulsifiers, catalysts,
activators, and modifiers used are virtually the same as those used in Process
No. 3 and are listed in Table A-7 in Appendix A.
3. Operating Parameters - The reaction temperature is controlled from 4° to
70°C.
4. Utilities - No data were available in the sources consulted for this study.
5. Waste Streams - As in crumb production, fugitive emissions of hazardous
organic vapors from process equipment are possible. Short production runs
are common because of the wide variety of products needed by consumers. After
each production run, all of the reactors and related process equipment must be
thoroughly rinsed with water. This rinse water contains high quantities of
uffcoagulated latex as well as other dissolved organics.
Cool ing-tower waste waters are associated with this process. These waste
waters characteristically have high total dissolved solids and moderate COD,
suspended solids, and pH. Corrosion inhibitors containing zinc and chromium
are also present.
6. EPA Source Classification Code - See Table 11.
7. References -
(1) Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limita-
tions Guidelines and New Source Performance Standards for the Tire
and Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D.C., 1974.
(2) Synthetic Rubber. George S. Whitby, ed. N.Y., Wiley, 1954.
41
-------
LATEX PRODUCTION
PROCESS NO. 9
Light Monomer Removal
1. Function - Unreacted monomer must be removed from the latex. Two separate
processes, vacuum stripping and steam stripping, are used to remove low-
boiling (light) and high-boiling (heavy) monomers, respectively. This process
is used to remove unreacted butadiene while Process 10 (Heavy Monomer Removal)
is used for styrene or acrylonitrile. The stripped butadiene vapors are
vented to the atmosphere. The butadiene-stripped latex is next passed to
heavy monomer removal for further stripping.
2. Input Materials - The input material to this process is the latex from
Process 8.A steam jet is sometimes used for the stripping process instead
of a vacuum pump.
3. Operating Materials - No data were available in the sources consulted.
4. Utilities - No quantitative data were available in the sources consulted.
Steam may be used for stripping.
5. Waste Streams - Frequent equipment cleanup contributes a liquid waste
stream containing high quantities of undissolved latex. In some plants alum
is added to this stream to coagulate the rubber particles to facilitate re-
moval .
No data were available on gaseous emissions. However, a 99% conversion
would produce an estimated 0.77 kg of unreacted butadiene per Gg of product
resulting in correspondingly large vented butadiene emissions from the stripper.
Cooling-tower waste waters are associated with this process. These
waste waters characteristically have high total dissolved solids and moderate
COD, suspended solids, and pH. Corrosion inhibitors containing zinc and
chromium are also present.
6. EPA Source Classification Code - See Table 11.
7. References -
(1) Environmental Protection Agency, Office of Air and Water Programs.
Effluent Guidelines Div. Development Document for Effluent Limita-
tions Guidelines and New Source Performance Standards for the Tire
and Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D.C., 1974.
(2) Synthetic Rubber. George S. Whitby, ed. N.Y., Wiley, 1954.
42
-------
LATEX PRODUCTION PROCESS NO. 10
Heavy Monomer Removal
1. Function - This process continues the monomer stripping which started in
Process 9 by using steam to remove excess high-boiling monomers. The stripped
vapors are condensed and sent to a receiver where the water is decanted and
discharged and the organic liquid is put in containers and sent to disposal.
The stripped latex is filtered through a series of screen filters to remove
large rubber particles and then stored in blend tanks.
2. Input Materials - The input materials to this process are the partially
stripped latex from Process 9 and steam.
3. Operating Parameters - Data were generally not available. Refer to
Process No. 5 for the data on steam stripping of styrene in crumb production.
4. Utilities - No data were available in the sources consulted.
5. Waste Streams - Again, frequent equipment cleanup is responsible for a
waste stream containing uncoagulated latex. The condensate water could con-
tain appreciable quantities of styrene or acrylonitrile. The screen filters
collect large amounts of rubber solids which must be removed and discarded
periodically.
As in most other synthetic rubber processes, fugitive emissions of
hazardous organic vapors from process equipment are possible.
Cooling tower waste waters are associated with this process. These
waste waters characteristically have high total dissolved solids and moderate
COD, suspended solids, and pH. Corrosion inhibitors containing zinc and
chromium are also present.
6. EPA Source Classification Code - See Table 11.
7. References -
1) Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limita-
tions Guidelines and New Source Performance Standards for the Tire
and Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D. C., 1974.
2) Synthetic Rubber. George S. Whitby, ed. N.Y., Wiley, 1954.
43
-------
LATEX PRODUCTION PROCESS NO. 11
Blending, Storage and Shipping
1. Function - The steps included in this process are used to transform the
stripped latex from Process 10 into a marketable product. The stripped and
filtered latex is stored in large blend tanks where antioxidants and other
additives are added. The latex is blended to insure consistent product
quality and is then drummed or shipped by tank car.
2. Input Materials - The stripped latex from Process 10 is the major input
material. Antioxidants and other additives are added depending on end use
of the latex.
3. Operating Parameters - No data were available in the sources consulted
for this study.
4. Utilities - No data were available in the sources consulted for this
study.
5. Waste Streams - Equipment cleanup contributes to the total plant load in
the form of high quantities of uncoagulated latex. In particular, cleanup of
tank cars and tank trucks is required after each trip.
6. EPA Source Classification Code - See Table 11.
7. References -
Environmental Protection Agency, Office of Air and Water Programs, Ef-
fluent Guidelines Div. Development Document for Effluent Limitations
Guidelines and New Source Performance Standards for the Tire and
Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D.C., 1974.
44
-------
Solution Crumb Production Processes
This segment of the Synthetic Rubber Industry is composed of processes which
produce crumb rubber by solution polymerization. Solution polymerization
uses catalysts of the Ziegler-Natta or Friedel-Crafts type to polymerize
monomers in an organic solvent. The production proceeds stepwise on a semi-
continuous basis 24 hours per day, 365 days per year.
Feedstocks for this operation and the corresponding elastomer products
are given in Table 24.
Table 24. MAJOR FEEDSTOCKS AND PRODUCTS FOR SOLUTION CRUMB PRODUCTION
Feedstock Elastomer
Butadiene BR
Butadiene, Styrene SBR
Isoprene IR
Isoprene, Isobutylene IIR
Ethylene, Propylene EPM
Source: Hedley, W. H., et al. Potential Pollutants from Petro-
chemical Processes, final report. Contract 68-02-0226,
Task 9, MRC-DA-406. Dayton, Ohio, Monsanto Research
Corp., Dayton Lab., Dec. 1973.
Information on utilities was found for entire plants rather than individual
processes. These data are summarized in Table 25.
45
-------
Table 25. UTILITY REQUIREMENTS FOR THE PRODUCTION OF
THREE TYPES OF SOLUTION CRUMB
(Plant Capacity 100 Gg/yr)
Solution Crumb
Product
IR
BR
EPM
Cooling Water
(m3/min)
58
43
167
Utilities Required
Process Water Power
(mVmiri) (kW)
4.2 9,000
0.9 6,700
5,700
Steam
(Gg/hr)
150
100
200
Some waste stream data were found for different solution crumb plants,
as summarized in Table 26.
Figure 3 is a process flow sheet for the solution crumb operation. Also
included in this operation are Monomer Storage (Process 1) and Caustic Wash
(Process 2), which were discussed in emulsion crumb production processes. The
unique processes in solution crumb production are Feed Drying (Process 12),
Polymerization (Process 13), Cement Storage (Process 14), Stripping and
Coagulation (Process 15), Monomer and Solvent Recovery (Process 16) and De-
watering and Product Finishing (Process 17).
46
-------
Table 26. RAW WASTE LOADS FOR SOME SOLUTION CRUMB RUBBER PLANTS
SBR Oil Extended
SBR Carbon-Black Extended
PBR Oil Extended
SBR Non-Extended
PBR Non-Extended
IR Non-Extended
BR, Part Oil Extended
BR, IR, EPDM Part Oil and
Carbon-Black Extended
Median
Flow
(m3/kg of Prod)
10,500
17,800
28,500
14,700
3,400
11,900
11,900
29,000
16,000
COD
(g/kg of Prod)
4.04
20.80
18.40
13.78
0.17
3.61
3.01
5.33
9.03
BOD
(g/kg of Prod)
0.09
0.18
1.55
0.82
0.06
1.37
1.37
3.57
1.13
ssa
(g/kg of Prod)
0.81
2.20
5.72
1.79
0.05
NA
5.37
3.71
2.81
Oil
(g/kg of Prod)
NA
NA
2.43
1.43
0.07
0.01
2.32
0.23
1.08
Determined downstream of crumb pits
NA = Data not available
Source: Environmental Protection Agency, Office of Air and Water Programs, Effluent Guidelines Div.
Development Document for Effluent Limitations Guidelines and New Source Performance Standards
for the Tire and Synthetic Segment of the Rubber Processing Point Source Category. EPA 440/1-
74-013-a. Washington, D.C., 1974.
-------
[RECOVERED 1
MONOMER TO
MONOMER STORAGE!
UNIHHBITtD
MONOMER
PROM PROCESS
[
RECOVERED
SOLVENT TO
SOLVENT STORASE
CATALYST
*
POLYMERIZATION
13
Q
MONOMER
AND
SOLVENT RECOVERY
-a
MAKE-UP WATER
CRUMB
RUBBER
CARBON SLACK SLURRY
Figure 3. FLOW DIAGRAM FOR SOLUTION CRUMB PRODUCTION
-------
SOLUTION CRUMB PRODUCTION
PROCESS NO. 12
Feed Drying
1. Function - This process is used to remove traces of water and other
extraneous materials from the input monomers and solvents prior to polymer-
ization. The dried monomers and solvents are then blended to give a "mixed
feed" which is further dried using a desiccant column. The dried mixed feed
is then sent to the polymerization reactors where polymerization occurs as
discussed in Process 13.
2- Input Materials - Input materials to this process are monomers from
caustic wash or storage and solvent. The most commonly used solvents are
hexane, pentane, toluene, methyl chloride, isopentane, and butene-benzene
mixtures. Table 27 lists some products and the solvents used in their
preparation.
Table 27. INPUT MATERIALS TO FEED DRYING
Product
Monomers
Solvents
PBR
EPM
IR
SBR
IIR
butadiene
ethylene, propylene
isoprene
styrene, butadiene
isoprene, isobutylene
hexane, toluene,
butene-benzene
hexane
hexane, pentane,
isopentane
hexane
methyl chloride
Source: Medley, W. H., et al. Potential Pollutants from
Petrochemical Processes, final report. Contract
68-02-0226, Task 9, MRC-DA-406. Dayton, Ohio,
Monsanto Research Corp., Dayton Lab., Dec. 1973.
3. Operating Parameters - Monomers and solvent are dried using a fractionating
drying tower and then further dried using a desiccant column. No operating
parameters were found in the sources consulted in this study.
4. Utilities - See Table 25.
5. Waste Streams - Data were not available in the sources consulted. The
drying process probably produces a "still bottom" containing water and im-
purities. The solid desiccant used for drying must be discarded or regenerated
periodically. This process also has the potential for release of hazardous
organic vapors because of leaks in the system.
6. EPA Source Classification Code - See Table 11.
49
-------
7. References -
1) Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limi-
tations Guidelines and New Source Performance Standards for the
Tire and Synthetic Segment of the Rubber Processing Point Source
Category. EPA 440/1-74-013-a. Washington, D.C., 1974.
2) Medley, W. H., et al. Potential Pollutants from Petrochemical
Processes, final report. Contract 68-02-0226, Task 9, MRC-DA-406.
Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
50
-------
SOLUTION CRUMB PRODUCTION
PROCESS NO. 13
Polymerization
1. Function - This process converts the monomer/solvent mixed feed in the
presence of catalysts into a solution containing rubber called ruber cement.
Solution polymerization occurs by an ionic mechanism and the initiators are
usually unstable in water. Polymerization occurs in a series of reactors
with the catalysts added to the mixed feed just prior to the first reactor.
The reaction temperature is carefully controlled using refrigerants. After
the desired conversion is reached, shortstops are added to termirvate the
reaction. The cement is then pumped to storage tanks for further processing.
2. Input Materials - Input materials to this process are the mixed feed
from Process 12, catalysts, and shortstops. Ziegler-Natta catalysts are
the^most widely used. A complete list is given in Table A-5 in Appendix A.
As in emulsion polymerization, shortstops such as sodium dithiocarbamate are
used to terminate the reaction. Modifiers such as tetrahydrofuran are
sometimes added as randomizing agents.
3. Operating Parameters - The reaction is highly exothermic and thus re-
frigeration equipment containing ammonia, brine, or glycol coolants must
be used. For IIR production, cooling is accomplished using liquid ethylene.
Table 28 gives some operating conditions for production of several elastomers.
Table 28. OPERATING CONDITIONS FOR SOLUTION POLYMERIZATION
Reaction Temperature
Product
EPM
IR
IIR
PBR
SBR
Catalyst
A1C13 + VC13
butyl lithium
A1C13
butyl lithium
T1CU
nickel
cobalt
alkyl lithium
(°C)
30 to 40
50
30
-100
50
-4 to 4
4
5
50
Solvent
hexane
hexane or pentane
isopentane
methyl chloride
hexane
toluene
toluene
butene-benzene
hexane
Source: Hedley, W. H., et al. Potential Pollutants from Petrochemical
Processes, final report. Contract 68-02-0226, Task 9, MRC-DA-406.
Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
The applied Science of Rubber. W. J. S. Naunton, ed. London,
Edward Arnold (Publishers) Ltd., 1961.
SI
-------
A variation of this process used for the production of EPM, termed sus-
pension polymerization, uses one of the monomers (propylene) as a solvent.
The polymerization occurs at -16°C using a Ziegler-Natta catalyst.
4. Utilities - See Table 25.
5. Waste Streams - Fugitive emissions from valves, seals, etc. could release
hazardous organic vapors. Since the process is operated on a water-free
basis equipment cleanup is accomplished using organic cleaning solvents.
The cleaning solvent is stored separately in drums or storage tanks. Process
pumps use oil seals to prevent water contamination of process streams.
This oil could enter area washdown wastes.
6. EPA Source Classification Code - See Table 11.
7. References -
1) Billmeyer, Fred W., Jr. Textbook of Polymer Science, 2nd Ed. N.Y.,
Wiley, 1971.
2) Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limita-
tions Guidelines and New Source Performance Standards for the Tire
and Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D. C., 1974.
3) Hedley, W. H., et al. Potential Pollutants from Petrochemical
Processes, final report. Contract 68-02-0226, Task 9, MRC-DA-406.
Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
4) Hargreaves, C. A., II and D. C. Thompson. Elastomers, Synthetic.
In: Kirk-Othmer Encyclopedia of Chemical Technology, Vol 7.
Anthony Standen, ed. N.Y., Wiley, 1968, pp. 676-716.
5) Synthetic Rubber. George S. Whitby, ed. N.Y., Wiley, 1954.
-------
SOLUTION CRUMB PRODUCTION PROCESS NO. 14
Cement Storage
1. Function - Cement storage tanks are used to blend various production runs
to obtain consistent product quality. In addition, antioxidants and extender
oil can be added during this processing step.
2. Input Materials - Input materials to this process include the cement from
Process 13, antioxidants, and extender oils. Tables A-5 and A-8 in Appendix
A list some commonly used antioxidants and extender oils.
3. Operating Parameters - No data were available in the sources consulted
ype
thT
for this study.
4. Utilities - See Table 25.
5. Haste Streams - Waste streams from this process result only from leaks of
cement or extender oil or from fugitive emissions of organic vapors.
6. EPA Source Classification Code - See Table 11.
7. References -
Environmental Protection Agency, Office of Air and Water Programs, Effluent
Guidelines Div. Development Document for Effluent Limitations Guidelines
and New Source Performance Standards for the Tire and Synthetic Segment of
the Rubber Processing Point Source Category. EPA 440/1-74-013-a. Washing-
ton, D. C., 1974.
53
-------
SOLUTION CRUMB PRODUCTION PROCESS NO. 15
Stripping and Coagulation
1. Function - The function of this process is to remove solvent and unreacted
monomer while coagulating the rubber into crumb form. Stripping occurs by con-
tacting the cement with hot water (IIR) or steam (PBR, EPM, IR). The crumb
slurry is sent to additional steam strippers for further removal of solvent
and monomer. The steam-organic vapor is sent to a recovery process while the
crumb slurry is further washed with water, screened, and processed as des-
cribed in Process 17. Carbon black masterbatching may also be done in this
process by adding a carbon black water slurry as described in Process 6. One
plant reportedly bypasses this process by recovering the rubber directly from
the cement, presumably using an extruder to separate the solvent from the rubber.
2. Input Materials - Input materials are the blended cement from Process 14
and steam. Wetting agents such as zinc stearate are sometimes added to control
particle size. Carbon black is an input material for carbon black masterbatch
rubbers.
3. Operating Parameters - No information was available in the sources consulted.
4. Utilities - See Table 25.
5. Waste Streams - The water used for slurrying the stripped crumb contributes
significantly to the liquid waste load. This stream will be discussed in Pro-
cess 17. Similarities between this process and emulsion crumb processes indi-
cate that significant quantities of dissolved and suspended organics could
result from frequent equipment cleanups. Fugitive emissions of hazardous or-
ganic vapors are also possible in this process. In contrast to emulsion crumb
production plants, solution crumb production plants generally have on-site steam
generation which results in a boiler blowdown liquid waste stream. Carbon-
black masterbatching generates a waste stream containing fine particulates.
6. EPA Source Classification Code - See Table 11.
7. References -
Environmental Protection Agency. Office of Air and Water Programs. Effluent
Guidelines and New Source Performance Standards for the Tire and Synthetic
Segment of the Rubber Processing Point Source Category. EPA 440/1-74-013-a.
Washington, D. C., 1974.
54
-------
SOLUTION CRUMB PRODUCTION PROCESS NO. 16
Monomer and Solvent Recovery
1. Function - The steps in this process serve to separate and purify the
unreacted monomer and solvent which were steam stripped in Process 15. The
steam, solvent, and monomers from the steam stripping process are condensed
and sent to a separator where the bottom aqueous layer is removed. The or-
ganic layer is then sent to a multi-stage fractionator where separation of
monomers and solvent occurs. The purified solvent and monomers are sent to
storage tanks.
2. Input Materials - The input material to this process is the solvent,
monomer, and steam mixture from Process 15.
3. Operating Parameters - No information was available in the sources con-
sulted.
4. Utilities - See Table 25.
5. Waste Streams - Liquid effluents from this process are the water stream
from the water separator and bottoms from the fractionator. This stream may
be stripped before discharge, so that monomer and solvent may be recovered.
Some reports indicate direct discharge of the stream into the plant waste
stream, however. Oily wastes (slops) produced in solvent recovery are sent
to purification plants or used as a waste fuel. As in virtually all elastomer
processes, fugitive emissions of organic vapors are possible. Purge vents
in recovery sections also release organic vapors as shown in Table 29.
Table 29. ORGANIC VAPORS RELEASED FROM PURGE VENTS IN EPM PRODUCTION
Source Emission Rate (g/kg product)
Solvent Recovery 6
Monomer Recovery 30
Source: Hedley, W. H., et al. Potential Pollutants from Petrochemical
Processes, final report. Contract 68-02-0226, Task 9, MRC-DA-
406. Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec.
1973.
Flow rates for the water stream were at 34 and 75 m3 for two processes
with the water stream in EPM production emitting 0.5 g of hexane/kg of
product.
6. EPA Source Classification Code - See Table 11.
55
-------
7. References -
1) Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limita-
tions Guidelines and New Source Performance Standards for the Tire
and Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D. C., 1974.
2) Hedley, W. H., et al. Potential Pollutants from Petrochemical Processes,
final report. Contract 68-02-0226, Task 9, MRC-DA-406. Dayton,
Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
56
-------
SOLUTION CRUMB PRODUCTION PROCESS NO. 17
Dewatering and Product Finishing
1. Function - This process takes the crumb slurry from Process 15, removes
the crumb rubber by screening, and then dries and bales the purified crumb
for shipment. The slurry rinse water is recycled to the coagulation process
with some make-up water. The screened crumb is dewatered using extruder dry-
ers or rotary filters and hot air dryers. The dried rubber is weighed and
pressed into 34 kg bales using hydraulic balers.
2. Input Materials - Input materials to this process are the stripped crumb
slurry from Process 15 and steam or hot air.
3. Operating Parameters - Operating conditions were not available in the
sources consulted in this study. Operating conditions should be similar to
those described in the Crumb Washing, Drying and Finishing Process in emulsion
crumb production processes.
4. Utilities - See Table 25.
5. Waste Streams - Overflow from the crumb rinse water is a large liquid
effluent in this process. This stream contains large amounts of coagulated
rubber which are removed in crumb pits. Other pollutants in this stream
include unblended carbon black or extender oil, catalyst residues, and un-
stripped solvent or monomer.
Drying of the rubber releases unstripped solvent monomer or other resi-
dues. Expeller drying of polybutadiene produces a waste stream with a flow
of 66 m3 per hour containing 25 g of catalyst residues per kg of product.
Gaseous emissions of unstripped solvent in air driers range from 0.5 to 5 g/kg
of product.
6. EPA Source Classification Code - See Table 11.
7. References -
1) Environmental Protection Agency, Office of Air and Water Programs,
Effluent Guidelines Div. Development Document for Effluent Limitations
Guidelines and New Source Performance Standards for the Tire and
Synthetic Segment of the Rubber Processing Point Source Category.
EPA 440/1-74-013-a. Washington, D. C., 1974.
2) Medley, W. H., et al. Potential Pollutants from Petrochemical
Processes, final report. Contract 68-02-0226, Task 9, MRC-DA-406.
Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
57
-------
APPENDIX A
RAW MATERIALS LISTS
59
-------
Table A-l. MONOMERS USED IN THE SYNTHETIC RUBBER INDUSTRY
Monomers
Elastomer Products
Butadiene
Styrene
Acrylonitrile
Vinyl Pyridine
Ethylene
Isoprene
Propylene
1, 5-Dicyclooctadiene
Isobutylene
Ethylene glycol
Propylene glycol
Adi pic acid
2, 4-Toluene diisocyanate
Vinylidene fluoride
Ethylene dichloride
Chlorotrifluoroethylene
Perf1uoropropylene
Bis(ehloroethyl)formal
Epichlorohydrin
Ethylene oxide
2-chloro-l, 3-butadiene
Hexafluoropropylene
Acrylic acid
Ethylidene norbornene
Ethyl aerylate
Dichlorosilanes
SBR, NBR, ABR, BR, COX
SBR
NBR, COX
SBR - Vinyl Pyridine
EPM, EPDM, CSM
IR, IIR
EPM, EPDM
EPDM
IIR
U
U
COX
U
FPM
T
FPM
FPM
T
CO, ECO
ECO
CR
FPM
COX
EPDM
ABR
SI
See Table 4 for key to acronyms.
Source: Handbook of Plastics and Elastomers. Charles A. Harper, ed.
N.Y., McGraw-Hill, 1975
Hargreaves, C. A., II and D. C. Thompson. Elastomers, Synthetic.
In: Kirk-Othmer Encyclopedia of Chemical Technology, Vol 7.
Anthony Standen, ed. N.Y., Wiley, 1968, pp. 676-716.
Rubber Technology and Manufacture, Claude M. Blow, ed London
Butterworths, 1971. '
60
-------
Table A-2. SOME CATALYSTS USED IN SOLUTION CRUMB PRODUCTION
Ziegler - Natta Catalysts
vanadium oxychloride + alkyl aluminum
cobalt salts or organic compounds + alkyl aluminum
nickel salts or organic compounds + alkyl aluminum
TiCU with aluminum trialkyl
TiU with an alkyl aluminum
Friedel - Crafts Catalysts
A1C13
BF3
Alfin catalysts
Mixture of the salt of a secondary alcohol and olefin
with sodium chloride
Other Catalysts
alkyl lithium
butyl lithium
propylene oxide and ferric chloride hydrolyzed adduct
Source: Cooper, W. Elastomers, Synthetic. In: Encyclopedia of Polymer
Science and Technology, Vol 5. H. F. Mark, ed. N.Y., Wiley,
1966, pp. 406-82.
Rubber Technology and Manufacture. Claude M. Blow, ed. London,
Butterworths, 1971.
The Applied Science of Rubber. W. J. S. Naunton, ed. London,
Edward Arnold (Publishers) Ltd., 1961.
61
-------
Table A-3. SOLVENTS USED IN SOLUTION CRUMB PRODUCTION
Solvent Product
hexane BR, EPM, IR, SBR
toluene BR
butene-benzene BR
pentane IR
isopentane IR
methyl chloride IIR
Source: Medley, W. H., et al. Potential Pollutants from
Petrochemical Processes, final report. Contract
68-02-0226, Task 9, MRC-DA-406, Dayton, Ohio,
Monsanto Research Corp., Dayton Lab., Dec. 1973.
62
-------
Table A-4. CARBON BLACK ASTM GRADE DESIGNATIONS*
ASTM No.
N110
N119
N166
N195
N219
N220
N231
N242
N270
N285
N293
N294
N296
N326
N327
N330
N339
N347
N351
N358
N363
N440
N472
N539
N542
N550
N568
N601
N650
N660
N754
N761
N762
N765
N770
N774
N779
N785
N787
N790
N907
N990
S212
S315
Industry Grade
SAP
SAF-LS
SAF-HS
SCF
ISAF-LS
ISAF
ISAF-LM
ISAF-HS
ISAF-HS
ISAF-HS
CF
SCF
CF
HAF-LS
HAF-LS
HAF
HAF-HS
HAF-HS
T HS
HAF-VHS
T LS
FF
ECF
FEF-LS
FEF-LS
FEF
FEF-HS
HMF
GPF-HS
GPF
SRF-LS
SRF-LM
SRF-LM NS
SRF HS
SRF-HM
SRF-HM-NS
SRF-HS
MPF
SRF-I-HS
SRF-HM
MT-NS
MT
SAF-LS-SC
HAF-LS-SC
a
Includes carbon blacks used by compounding industries
Source: Gerstle, R. W. Industrial Process Profiles for
Environmental Use, Vol 1., 1st Ed. Terry Parsons, ed
EPA Report 600/2-76-051 a.
63
-------
Table A-5. POLYMERIZATION ADDITIVES
CATALYST SYSTEM (Initiators, Activators, and Catalysts)
Peroxide
Peroxysulfate
(e.g. potassium peroxysulfate)
Diisopropyl monohydroperoxide
Paramethane hydroperoxide
Ferrous sulfate
Potassium pyrophosphate
Trisodium phosphate
Ethylenediaminetetraacetic acid
Sodium formaldehyde sulfoxylate
Sodium dethionite
MODIFIERS AND REGULATORS
Dodecanethiol
Sulphur
Tetrahydrofuran
Diisopropylxanthogen disulfide
ANTI-OXIPANTS
Phenyl-B-naphthylamine
Phenylene diamine
SHORT STOPS
Hydroquinone
Sodium dimethyldithiocarbamate
Sodium polysulfide
Polyamine H
Source: Cooper, W. Elastomers, Synthetic. In: Encyclopedia of Polymer
Science and Technology, Vol 5. H. F. Mark, ed. N.Y., Wiley, 1966,
pp. 406-82.
Hedley, W. H., et al. Potential Pollutants from Petrochemical
Processes, final report. Contract 68-02-0226, Task 9, MCRA-DA-406.
Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
Synthetic Rubber. George S. Whitby, ed. N.Y., Wiley, 1954.
The Applied Science of Rubber. W. J. S. Naunton, ed. London,
Edward Arnold (Publishers) Ltd., 1961.
64
-------
Table A-6. EMULSIFIERS
Fatty Acid Soaps
Sodium Soap of Laurie Acid
Sodium Soap of Myristic Acid
Sodium Soap of Palmitic Acid
Sodium Soap of Stearic Acid
Sodium Soap of Eloidic Acid
Rosin Acid Soaps
Potassium disproportioned rosin mixed with a sodium
alkyl naphthalene sulfonate
Source: Synthetic Rubber. George S. Whitby, ed.
N.Y., Wiley, 1954.
The Applied Science of Rubber. W. J. S. Naunton, ed.
London, Edward Arnold (Publishers) Ltd., 1961.
65
-------
Table A-7. RECIPES FOR SOME ELASTOMER PRODUCTS
SBR
Hot
Parts by Weight
Cold
Constituent
Butadiene 75.0
Styrene 25.0
Dodecyl mercaptan 0.5
Potassium peroxysulfate 0.3
Soap flakes 5.0
Water 180.0
Diisopropyl benzyl monohydroperoxide —
Paramethane hydroperoxi de
Ferrous sulfate
Potassium pyrophosphate
Trisodium phosphate
EDTA
Sodium formaldehyde sulfoxylate
NBR
Constituent
Butadiene (freshly distilled)
Acrylonitrile
Soap flakes
"Stearic acid"
tert-Dodecyl mercaptan
Potassium chloride
Sodium pyrophosphate (anhyd. basis)
Ferric sulfate (anhyd. basis)
Hydrogen peroxide (20% soln.) (anhyd. basis)
Water (deionized or distilled)
Recipe 1 Recipe 2
72.00 71.00
28.00 29.00
0.20 0.18
— —
4.00 4.50
180.00 200.00
0.08
0.03
0.14 0.03
0.18
0.50
0.035
0.08
Parts by Weight
75
25
4.5
0.6
0.5
0.3
0.1
0.02
0.35
180
66
-------
Table A-7. RECIPES FOR SOME ELASTOMER PRODUCTS (Continued)
Constituent Parts by Weight
Chloroprene 100
N Wood rosin 4 Dissolved in
Sulfur 0.6 the monomer
Water 150
Sodium hydroxide 0.8
Sodium salt of naphthalene sulfonic acid-formaldehyde
condensation product 0.7
Potassium persulfate 0.2 to 1.0
Source: Hargreaves, C. A., II and D. C. Thompson. Elastomers, Synthetic.
In: Kirk-Othmer Encyclopedia of Chemical Technology, Vol 7.
Anthony Standen, ed. N.Y., Wiley, 1968, pp. 676-716.
Synthetic Rubber. George S. Whitby, ed. N.Y., Wiley, 1954.
67
-------
Table A-8. OTHER RAW MATERIALS USED BY THE SYNTHETIC RUBBER INDUSTRY
Raw Material Use
Sodium Hydroxide Inhibiter Removal
Sodium Chloride Coagulating liquor
Sulfuric acid Coagulating liquor
Mineral oils
naphthenic
Oil extenders
aromatic
highly aromatic
Aluminum Sulfate (Alum) Coagulating liquor
Sodium sulfite Shortstop enhancer
tert-Butyl catechol Inhibiter
Source: Hedley, W. H., et al. Potential Pollutants from Petrochemical
Processes, final report. Contract 68-02-0226, Task 9, MRC-DA-406.
Dayton, Ohio, Monsanto Research Corp., Dayton Lab., Dec. 1973.
Rubber Technology and Manufacture. Claude M. Blow, ed. London,
Butterworths, 1971.
Synthetic Rubber. George S. Whitby, ed. N.Y., Wiley, 1954.
The Applied Science of Rubber. W. J. S. Naunton, ed. London,
Edward Arnold (Publishers) Ltd., 1961.
68
-------
APPENDIX B
PRODUCTS
69
-------
Table B-l. GENERAL PHYSICAL PROPERTIES OF SYNTHETIC ELASTOMERS
Elastomer
SBR
CR
NBR
IIR
EPT
CSM
ABR
T
SI
U
FPM
IR
BR
COX
EC
Tensile
Strength
MPa
BBBBBBIBBBIIBBHBBBBHBBIBIBIIBBB^^
21
22
21
17
19
23
12
9
10
55
19
28
24
15
17
Durom-
eter
Shore A
••••••^•^••^••^•••^^^^^^^^•^^^^
40-95
30-90
40-90
35-90
35-90
40-90
40-95
20-80
20-90
60-95
60-90
25-95
35-95
50-85
50-85
%
elonga- Service
ti on temp .
^^HB^IVIIIBBBBBBBBBBBBBBBBB^^
450
700
650
500
350
500
350
400
750
700
300
600
550
400
450
-55 to 93
-55 to 121
-55 to 135
-55 to 121
-62 to 149
-55 to 135
-29 to 177
-40 to 107
-95 to 288
-40 to 121
-40 to 232
-62 to 93
-73 to 93
-68 to 135
-40 to 163
Tear
resistance
^^**^^^ta— Wft«^»l«M>*^^^^k^^^^^
Good
Good
Good
Very Good
Good
Good
Fair
Good
Poor
Excellent
Fair
Very Good
Very Good
Very Good
Good
Abrasion
resistance
Good to
Excellent
Excellent
Good to
Excellent
Good
Excellent
Excellent
Good
Poor
Poor
Superior
Good
Excellent
Excellent
Very
Excellent
Good
Compres-
sion set
• - •- --
Good
Fair to
Good
Good
Poor to
Fair
Fair
Fair to
Good
Fair
Poor
Good to
Excellent
Excellent
Good to
Excellent
Good
Good
Fair
Good
Flame
resistance
Poor
Good
Poor
Poor
Poor
Good
Poor
Poor
Fair
Poor
Excel
Poor
Poor
Poor
Fair
to Fair
to Fair
to Good
to Fair
lent
to Good
Source: Handbook of Plastics and Elastomers. Charles A. Harper, ed. N.Y., McGraw-Hill, 1975.
-------
Table B-2. TYPICAL TRADE NAMES AND SUPPLIERS FOR ELASTOMERS
Elastomer
Typical trade names and suppliers
Isoprene (IR)
Neoprene (CR)
Nitrile (NBR)
Butyl (IIR)
EPT (EPM) copolymer
EPDM terpolymer
Hypalon (CSM)
Acrylic (ABR)
Polysulfide (T)
Silicones (SI)
Urethane (U)
Fluoroelastomers (FPM)
Butadiene (BR)
Carboxylic (COX)
Epichlorohydrin (ECO, CO)
Natsyn (Goodyear Chemical)
Ameripol SN (B. F. Goodrich)
Isoprene (Shell Chemical)
Neoprene (E.I. du Pont)
Hycar (B. F. Goodrich)
Chemigum (Goodyear Chemical)
FR-N (Firestone)
Enjay Butyl (Exxon)
Petro-Tex Butyl (Petro-Tex Chemical)
Nordel (E. I. du Pont)
Vistalon (Exxon)
Epear (B. F. Goodrich)
Hypalon (E. I. du Pont)
Cyanacn'l (American Cyanamid)
Hydar (B. F. Goodrich)
Acrylon (Borden Chemical)
Thiokol (Thiokol Chemical)
Silastic (Dow Corning)
SE Rubber (General Electric
Silicones (Union Carbide)
Adiprene (E. I. du Pont)
Estane (B. F. Goodrich)
Genthane (General Tire and Rubber)
Fluorel (3M)
Viton (E. I. du Pont)
Diene (Firestone)
Ameripol CB (B. F. Goodrich)
Hycar (B. F. Goodrich)
Hydrin (B. F. Goodrich)
Source: Handbook of Plastics and Elastomers. Charles A. Harper, ed.
N.Y., McGraw-Hill, 1975.
71
-------
Table B-3. THE IISRP NUMBERING SYSTEM FOR SBR
Series
Rubber
1000
1500
1600
1700
1800
1900
Hot-polymerized non-pigmented rubbers
Cold-polymerized non-pigmented rubbers
Cold-polymerized black masterbatch with 14 or less
parts of oil per 100 parts of SBR
Cold-polymerized oil masterbatch
Cold-polymerized oil-black masterbatch with more than
14 parts of oil per 100 parts SBR
Emulsion resin rubber masterbatches
Source: Rubber Technology and Manufacture. Claude M. Blow, ed. London,
Butterworths, 1971.
Table B-4. THE IISRP NUMBERING SYSTEM FOR STEREO AND RELATED RUBBERS
BRa
Dry polymer 1200-1249
Oil -extended 1250-1299
Black masterbatch 1300-1349
Oil -black masterbatch0 1350-1399
Miscellaneous 1450-1499
IRa
2200-2249
2250-2299
2300-2349
2350-2399
2450-2499
EPM
100-149
150-199
200-249
250-299
350-399
Notes: ^Includes copolymers.
Dry polymer containing any quantity of oil.
cBlack masterbatch containing any quantity of oil.
Source: Rubber Technology and Manufacture. Claude M. Blow, ed. London,
Butterworths, 1971.
72
-------
Table B-5. USE OF VARIOUS SYNTHETIC ELASTOMERS IN THE UNITED STATES (1962)
Percent of
total synthetic
Elastomer Use elastomer used
SBR
NBR
IIR
CR
U
CSM
FPM
SI
tires
footwear
mechanical goods
paper, leather, and textile finishes
mechanical goods
tubes and curing bags
mechanical goods
ti res
mechanical goods
wire and cable
footwear
adhesives
tires
adhesives, binders, coatings
mechanical goods
industrial tires
automotive
wire and cable
seals, gaskets
automotive
electrical
appliances
68
7
5
36
31
56
20
17
52
22
6
6
5
37
25
8
30
20
80-90
15
10
10
Source: Cooper, W. Elastomers, Synthetic. In: Encyclopedia of Polymer
Science and Technology, Vol 5. H. F. Mark, ed. N.Y., Wiley,
1966, pp. 406-82.
73
-------
APPENDIX C
PRODUCERS
75
-------
Table C-l. COMPANY PRODUCT LIST
Company
Amco, Inc.
American Can Company
American Cyanamid
American Synthetic Rubber
Arco/Polymers, Inc.
Ashland Chemicals
BASF, Wyandotte Corp.
Samuel Bingham Co.
Borden, Inc.
Cal Polymers, Inc.
Celanese Corporation
Ciba-Geigy Corporation
(Ran Plastics Division)
Cities Service
(Columbian Chemicals
Division)
Communications Technology
Corp.
Conap, Inc.
Copolymer Rubber
Location
South Gate, CA
Los Angeles, CA
Bound Brook, NJ
Louisville, KY
Beaver Valley, PA
Bay town, TX
Wyandotte, MI
Franklin Park, IL
Iliopolis, IL
Leominster, MA
Long Beach, CA
Charlotte, NC
East Lansing, MI
Lake Charles
Los Angeles, CA
Olean, NY
Baton Rouge, LA
Addis, LA
Product1
U
U
ABR
U
BR
SBR
SBR (carboxyla-
ted)
SBR
SBR
U
U (captive)
SBR latex \
SBR latex f
U
SBR latex
U
IIR
U
U
SBR
NBR
EPM
EPDM
Annual
Capaci ty
(Gg)
na
na
na
na
56
100
na
20
59
na
na
16
na
12
na
41
na
na
125
5
na
25
C.P.L. Corporation
East Providence, RI U
na
76
-------
Table C-l. COMPANY PRODUCT LIST (Continued)
Company
Dart Industries
Davidson Rubber Company
Dayco Corporation
Deering-Milliken, Inc.
(Mil liken Division)
Dennis Chemical Company
The Dexter Corporation
Diamond- Shamrock Corpor-
ation
Disogrin Industry Corpor-
ation
Dow Corning/ Dow Chemical
E.I. du Pont de Nemours/
du Pont Elastomers
Eagle-Picher Industries,
Inc.
Exxon Corporation
(formerly EnJay Corpora-
tion)
Location
Bayport, TX
Dover, NH
Dayton, OH
Imman, SC
St. Louis, MO
City of Industry, CA
Olean, NY
Astabula, OH
Manchester, NH
Dal ton, GA
Gales Ferry, CT
Pittsburg, CA
Midland, MI
Costa Mesa, CA
Midland, MI
Beaumont, TX
Deep Water Point, NJ
LaPlace, LA
Louisville, KY
Victoria, TX
Willoughby, OH
Baton Rouge, LA
Bavtown, TX
Product1
SBR latex
Annual
Capacity
(Gg)
5
U (captive) na
U (captive) na
SBR-vinylpy- na
ridine latex
U
U
U
T
na
na
na
na
U (captive) na
SBR latex
SBR latex
SBR latex
SBR latex
SI
SI
CSM
EPDM
20
na
na
23
54
FPM na
Polyesterelastomer na
U na
CR
CR
CR
U
SI
EPM
EPDM
IIR
IIR
36
140
na
na
na
na
32
76
92
77
-------
Table C-l. COMPANY PRODUCT LIST (Continued)
Company
Firestone Tire and Rubber
Co.
The Flamemaster Corp.
GAP
Genera] Electric
General Tire and Rubber
The B.F. Goodrich Company/
Goodrich Gulf Chemicals
Location
Akron, OH
Lake Charles, LA
Orange, TX
Potts town, PA
Sun Valley, CA
Chattanooga, TN
Waterford, NY
Mogadore, OH
Akron, OH
Avon Lake, OH
Louisville, KY
Orange, TX
Pedricktown, NJ
Port Neches, TX
Annual
Capacity
Product1 (Gg)
NBR
SBR
SBR latex
SBR vinylpy-
ridine latex
SBR
BR
SBR
SBR aery Ion i-
trile latex
T
U
SBR latex
SI
SBR vinylpyri-
dine latex
BR
NBR
COX latex
Polybutadiene-
styrene-acry-
lonitrile latex
SBR latex ( car-
boxy lated)
CO
ECO
U
ABR
NBR
NBR latex
SBR
EPDM
BR
IR
ABR
SBR
SBR latex
5
46
47
na
331
86
na
na
na
na
30
na
na
na
14
na
na
na
4.5
na
na
na
28
na
na
25
101
51
na
142
5
78
-------
Table C-l. COMPANY PRODUCT LIST (Continued)
Company
The Goodyear Tire and
Rubber Co.
W.R. Grace (Dewey &
AT my)
Hardman, Inc.
Hercules
Hexcel Corporation
Indpol
Isochem Resins Co.
Midwest Manufacturing
Corporation
Minnesota Mining and
Manufacturing Company
Mobay Chemical Corporation
Morton-Norwich Products
N. L. Industries, Inc.
Location
Akron, OH
Beaumont, TX
Houston, TX
St. Mary's, OH
Owensboro, KY
South Acton, MA
Belleville, NJ
Hattiesburg, MS
Chatsworth, CA
Cucamonga, CA
Lincoln, RI
Burlington, IA
Decatur, AL
St. Paul, MN
New Martins vi lie, WV
Ringwood, IL
Bayonne, NJ
Annual
Capaci ty
Product1 (Gg)
NBR
SBR
SBR latex
SBR (carboxyla-
ted)
SBR- vinyl pyri-
dine latex
BR
IR
NBR
SBR
U
SBR latex
NBR
SBR latex
U
CO
ECO
U
U
SI
U
FPM
U (captive)
U
U
U
5
54
36
na
na
127
150
11
386
na
7
na
7
na
4.5
na
na
na
na
na
na
na
na
na
na
Occidental Petroleum
Corporation
Hicksville, NY
na
79
-------
Table C-1. COMPANY PRODUCT LIST (Continued)
Company
Petro-Tex Chemicals
Phillips Petroleum
Polymir Industries
Products Research and
Chemicals
K.J. Quinn & Company, Inc.
Raffi and Swans on
H. H. Robertson Co.
Shell Chemical Company
Smooth-On, Inc.
Solar Chemical Corp.
(Polysar Latex, Inc.)
Standard Brands, Inc.
Stauffer Chemical
(SWS Silicones Division)
Sybron (Kerr Manufactur-
ing Div.)
Texas-U.S. Chemical Co.
Textron, Inc.
Thiokol Chemical Corpora-
tion
Location
Houston, TX
Borger, TX
Oakland, CA
Gloucester City, NO
Glendale, CA
Maiden, MA
Wilmington, MA
Saukville, HI
Belpre, OH
Gillette, NJ
Chattanooga, TN
Cheswold, DE
Kensington, GA
Adrian, MI
Matawan, NJ
Romulus, MI
Port Neches, TX
Bellevue, OH
Moss Point, MS
Trenton, NJ
Product1
CR
BR
SBR
U
T
T
U
U
U
U
U
U (captive)
SBR latex
NBR
SBR latex
SBR latex
SI
SI
T
SI
BR
SBR
U
ABR
T
U
Annual
Capacity
(fig)
27
56
141
na
na
na
na
na
na
na
na
na
30
na
20
25
na
na
na
na
na
184
na
na
na
na
80
-------
Table C-l. COMPANY PRODUCT LIST (Continued)
Company
Trancoa Chemical Corp.
Union Oil Company of
California
Uni royal, Inc.
Union Carbide
The Upjohn Company
Vulcanized Rubber &
Plastics Co.
Witco Chemical Corp.
Location
Reading, MA
Charlotte, NC
La Mirada, CA
Baton Rouge, LA
Gas torn' a, NC
Geismar, LA
Navgatuck, CT
Painsville, OH
Scotts Bluff, LA
Sisterville, WV
LaPorte, TX
Torrance, CA
Morrisville, PA
New Castle, DE
Clearing, IL
Product1
U
SBR latex
SBR latex
NBR
U
EPDM
U
NBR
SBR latex
SI
U
U
SI
U
U
Annual
Capacity
(Gg)
na
8
9
14
na
44
na
14
na
na
na
na
na
na
na
xUnless specifically indicated, products listed do not include those used
captively. See Table 4 for a definition of acronyms. Polyurethane
elastomers account for less than 0.5% (14 Gg) of elastomer production.
na = capacity data unavailable
Source: 1976 Directory of Chemical Producers.
81
-------
Table C-2. LOCATION OF U. S. SYNTHETIC RUBBER PRODUCING PLANTS
STATES & AREA
New England
Connecticut
Massachusetts
New Hampshire
Rhode Island
Mid-Atlantic
Delaware
New Jersey
New York
Pennsylvania
Piedmont
Kentucky
North Carolina
South Carolina
West Virginia
South
Alabama
Georgia
Louisiana
Mississippi
Tennessee
Texas
Midwest and West
California
Illinois
Iowa
Michigan
Minnesota
Missouri
Ohio
Wisconsin
TOTAL
SBR1
3
1
2
4
1
3
6
3
2
1
14
2
3
2
7
13
2
1
1
9
40
BR NBR1 EPM2 OTHER
1 8
1
1 3
2
2
1 18
1 1
12
4
1
1 4
1 1
1
2
5 3 6 14
1
25 2
4
511 4
1 5 34
12
3
1
3
1
1
1 5 12
1 1
7 10 6 78
TOTAL
12
2
6
2
2
23
3
12
4
4
11
5
3
1
2
42
1
2
12
4
2
21
53
14
4
1
4
1
1
27
1
141
Notes: 1) Including latex
2) Including EPDM
Source: 1976 Directory of Chemical Producers.
82
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Table C-3. U. S. PRODUCTION OF SOME SPECIALTY ELASTOMERS, 1967
Elastomers Production, Gg (106lbs)
FPM 1 ( 2.5)
CSM 36 (80 )
SI 3 ( 6.5)
T 4 ( 9.0)
ABR 1.5 ( 3.0)
SBR - vinyl pyridine terpolymer 8 (17.0)
U 30 (65.0)
TOTAL 83 (183.0)
Note: Total 1965 Production of Synthetic Rubber was 1843 Gg (4060 106 Ibs)
Source: Hargreaves, C. A., II and D. C. Thompson. Elastomers, Synthetic.
In: Kirk-Othmer Encyclopedia of Chemical Technology, Vol 7.
Anthony Standen, ed. N.Y., Wiley, 1968, pp. 676-716.
S3
-------
TECHNICAL REPORT DATA
(Please read Instructions on ihc reverse before completing)
1. REPORT NO.
EPA-600/2-77-023i
3. RECIPIENT'S ACCESSIOf*NO.
4. TITLE AND SUBTITLE
Industrial Process Profiles for Environmental Use:
Chapter 9. The Synthetic Rubber Industry
5. REPORT DATE
February 1977
6. PERFORMING ORGANIZATION CODE
7, AUTHOR(S)
Jerry 'Parr, Terry B. Parsons and Nancy P. Phillips
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Radian Corporation
8500 Shoal Creek Boulevard
P.O. Box 99W
Austin, Texas 78766
1O. PROGRAM ELEMENT NO.
1AB015
11. CONTRACT/GRANT NO.
68-02-1319, Task 3*+
12. SPONSORING AGENCY NAME AND ADDRESS
Industrial Environmental Research Laboratory
Office of Research and Development
U.S. ENVIRONMENTAL PROTECTION AGENCY
Cincinnati, Ohio !)5268
13. TYPE OF REPORT AND PERIOD COVERED
Initial: 8/75-11/76
14. SPONSORING AGENCY CODE
EPA/600/12
IS. SUPPLEMENTARY NOTES
16. ABSTRACT
The catalog of Industrial Process Profiles for Environmental Use was developed as an
aid in defining the environmental impacts of industrial activity in the United States,
Entries for each industry are in consistent format and form separate chapters of the
study. The synthetic rubber industry is comprised of companies which produce a
synthetic vulcanized elastomer by polymerization or copolymerization of monomers
derived from petroleum or natural gas. The industry is discussed in three operations:
(1) Emulsion Crumb Production, (2) Latex Production, and (3) Solution Crumb Produc-
tion. Three process flow sheets and seventeen process descriptions have been pre-
pared to characterize the industry. Within each process description available
data have been presented on input materials, operating parameters , utility require-
ments and waste streams. Data related to the subject matter, including company,
product and raw material data, are included as appendices.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
Pollution
Synthetic rubber
Emulsion crunb production
Latex production
Solution crumb production
Synthetic elastomers
Vulcanization
Process doserip.t.lnn.
8. DISTRIBUTION STATEMENT
Release to Public
b.lDENTIFIERS/OPEN ENDED TERMS
Air Pollution Control
Water Pollution Control
Solid Waste Control
Stationary Sources
Rubber Industry
Process Assessment
Environmental Impact
19. SECURITY CLASS (This Report)
— Unclassified
20. SECURITY CLASS"7'/Viwpage~,
Unclassified
COSATI Field/Croup
07C
13B
11J
21. NO. OF PAGES
92
22. PRICE
EPA Form 2220-1 (9-73)
84
*USGPO: 1978 — 757-086/0807
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