DRAFT
    DEVELOPMENT DOCUMENT FOR
  EFFLUENT LIMITATIONS GUIDELINES
  AND STANDARDS OF PERFORMANCE
   RUBBER PROCESSING INDUSTRY
  PREPARED BY ROY F. WESTON, INC.
       FOR UNITED STATES
ENVIRONMENTAL PROTECTION AGENCY
 UNDER CONTRACT NUMBER 68-01-1510
        DATED: June, 1973

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                                                                  DRAFT
                                 NOTICE
The attached document is a DRAFT CONTRACTOR'S REPORT.   It includes
technical information and recommendations submitted by the Contractor
to the United States Environmental  Protection Agency ("EPA")  regarding
the subject industry.  It is being distributed for review and comment
only.  The report is not an official EPA publication and it has  not
been reviewed by the Agency.

The report, including the recommendations, will  be undergoing
extensive review by EPA, Federal and State agencies, public interest
organizations and other  interested groups and persons during the coming
weeks.  The report and in particular the contractor's recommended
effluent limitations guidelines and standards of performance is
subject to change in any and all respects.

The regulations to be published by EPA under Sections 30Mb) and 306
of the Federal Water Pollution Control Act, as amended, will be  based
to a large extent on the  report and the comments received on it.
However, pursuant to Sections 30Mb) and 306 of the Act, EPA will
also consider additional  pertinent  technical and economic  information
which  is developed  in the course of review of this  report by the
public and within EPA.   EPA  is currently performing an economic
impact analysis  regarding the subject  industry, which will be taken  into
account as part of  the  review of the  report.  Upon  completion of
the  review process,  and  prior to final promulgation of  regulations,
an EPA report will  be  issued setting  forth EPA's conclusions con-
cerning  the subject  industry, effluent  limitations  guidelines and
standards of performance applicable to such  industry.   Judgments
necessary to promulgation of regulations  under Sections  30A(b) and
306 of the Act, of  course,  remain  the  responsibility of  EPA.  Subject
to these  limitations,  EPA is making this  draft contractor's  report
available  in order  to  encourage  the widest possible participation
of interested  persons  in the decision  making process at  the  earliest
possible  time.

The  report  shall  have  standing  in  any EPA proceeding or court
proceeding only  to  the  extent  that it represents  the  views of the
Contractor who studied  the  subject industry  and prepared the infor-
mation and  recommendations.   It  cannot be cited,  referenced, or
 represented  in any  respect  in  any  such proceedings  as  a statement
of EPA's  views regarding the subject  industry.


                                 U.S.  Environmental  Protection Agency
                                 Office of Air and Water Programs
                                 Effluent Guidelines Division
                                 Washington,  D.C.   20^60
                              ii

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                                                                    DRAFT
                                 ABSTRACT
This document presents the findings of an extensive study of the
rubber processing industry by Roy F. Weston,  Inc.  for the Environmental
Protection Agency, for the purpose of developing effluent limitation
guidelines, Federal standards of performance, and  pretreatment standards
for the industry, to implement Sections 30*f,  306,  and 307 of the
Federal Water Pollution Control  Act, as amended (33 USC  1251, 131^,
and 1316; 86 Stat 816).

Effluent  limitation guidelines contained herein set forth the degree
of effluent reduction attainable through the  application of the best
practicable control technology currently available and the degree of
effluent  reduction attainable through the application of the best
available technology economically achievable, which must be achieved
by existing point sources by July 1, 1977 and July 1, 1983, respectively.
The Standards of Performance for new sources  contained herein set
forth the degree of effluent reduction which  is achievable through
the application of the best available demonstrated control technology,
processes, operating methods, or other alternatives.

The development of data and recommendations in the document relate to
the overall rubber processing industry, which is divided into two
major groups, tire and inner tube and synthetic rubber,  and further
into five sub-categories, on the basis of the characteristics of
the manufacturing processes involved.  Separate effluent limitations
were developed for each category on the basis of the level of raw
waste load as well as on the degree of treatment achievable by sugges-
ted model systems.  These systems include both biological and physical/
chemical  treatment, and for the synthetic rubber sub-categories treat-
ment of the secondary effluent by carbon adsorption.

Supportive data and the rationale for development of the proposed
effluent  limitation guidelines and standards  of performance are
contained in this report.
                                   iii
 NOTICE:  THESE  ARE  TENTATIVE  RECOMMENDATIONS  BASED  UPON  INFORMATION
 IN THIS  REPORT  AND  ARE  SUBJECT  TO  CHANGE  BASED  UPON COMMENTS  RECEIVED
 AND FURTHER  INTERNAL  REVIEW BY  EPA.

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                                                                    DRAFT
                            CONTENTS


Section                                                              page

        ABSTRACT                                                      j i I

        CONTENTS                                                       iv

        FIGURES                                                       vii

        TABLES                                                       viii

  I      CONCLUSIONS                                                   1-]

 II      RECOMMENDATIONS                                              |)-]

Mi      INTRODUCTION                                                Ill-l

           Purpose and Authority                                    Ill-l
           Summary of Methods Used for Development of the
              Effluent Limitation Guidelines and Standards
              of Performance
           General Description of the Industry
              Tire and Inner Tube Industry
                 Tire Manufacture
                 Inner Tube Manufacture
           Synthetic Rubber Industry
              General
              Synthetic Rubber Production
                 Emulsion Crumb Production
                 Solution Crumb Production
                 Latex Production
           Summary
1-2
1-4
1-4
1-4
1-15
1-15
1-15
1-21
I-21
I-27
1-30
1-34
 IV     INDUSTRY CATEGORIZATION                                      IV-1

           Introduction                                              IV-1
           Tire and Inner Tube Industry                              IV-1
           Synthetic Rubber Industry                                 IV-7

  V     WASTE CHARACTERIZATION                                        V-1

           Tire and Inner Tube Industry                               V-1
           Synthetic Rubber Industry                                  V-7
              General
              Emulsion Crumb Rubber Subcategory                       V-7
              Solution Crumb Rubber Subcategory                       V-11
              Latex Rubber Subcategory                                V-14
                                    Iv

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                                                                    DRAFT
                             CONTENTS
                            (continued)
Section                                                            Page

  VI    SELECTION OF POLLUTION PARAMETERS                          Vl-1

           Tire and Inner Tube Industry                            Vl-1
           Synthetic Rubber Industry                               VI-3

 VII    CONTROL AND TREATMENT TECHNOLOGY                          VI1-1

           Survey of Selected Plants                              VI 1-1
              General  Approach and Summary                        VI1-1
              Tire and Inner Tube Plants                          VII-4
              Synthetic Rubber Plants                             VI1-15
           Summary of Control and Treatment Technology            VI 1-32
              Tires and Inner Tubes                               VI 1-32
              In-Plant Control                                    VI 1-32
              End-of-Pipe Treatment                               VI 1-35
           Synthetic Rubber                                       VII-3&
              In-Plant Control                                    VI 1-36
              End-of-Pipe Treatment                               VI 1-38

VIII    COST, ENERGY AND NON-WATER QUALITY ASPECTS               VI I 1-1

           Tire and Inner Tube Industry                          VI 1-1
           Synthetic Rubber Industry                             VI 1-7
              Emulsion Crumb Sub-category                        VI 1-7
              Solution Crumb Sub-category                        VI 1-11
              Latex Sub-category                                 VI 1-12

  IX    BEST PRACTICABLE CONTROL TECHNOLOGY CURRENTLY
        AVAILABLE-EFFLUENT LIMITATIONS                             IX-1

           Tire and Inner Tube Facilities                          IX-1
              Identification of Best Practicable Control
                 Technology Currently Available                    IX-1
              Effluent Loadings Attainable With Proposed
                 Technologies                                      IX-4
           Synthetic Rubber Industry                               IX-5
              Identification of Best Practicable Control
                 Technology Currently Available                    IX-5
              Emulsion Crumb Sub-category                          IX-5
              Solution Crumb Sub-category                          IX-7
              Latex Sub-category                                   IX-8
           Effluent Loadings Attainable With Proposed
                Technologies                                       IX-8
              Emulsion Crumb Sub-category                          IX-8
              Solution Crumb Sub-category                          IX-9
              Latex Sub-category                                   IX-9

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                                                                    DRAFT
                              CONTENTS
                            (continued)

Section                                                            Page

    X   BEST AVAILABLE TECHNOLOGY LIMITATIONS ECONOMICALLY
        ACHIEVABLE—EFFLUENT LIMITATIONS                            X-1

           Tire and  Inner Tube Industry                             X-1
           Synthetic Rubber Industry                                X-2
               Identification of Best Practical Control
                 Technology Currently Available                     X-2
               Emulsion Crumb Sub-category                           X-2
               Solution Crumb Sub-category                           X-5
               Latex Sub-category                                    X-5
           Effluent  Loading Attainable with Proposed Technologies   X-6
               Emulsion Crumb Sub-category                           X-6
               Solution Crumb Sub-category                           X-6
               Latex Sub-category                                    X-7

   XI   NEW-SOURCE PERFORMANCE STANDARDS                           XI-1

           Tire and  Inner Tube Production Facilities               XI-1
           Synthetic Rubber Industry                               XI-1
           Pretreatment  Recommendations                            XI-2
               Tire and  Inner Tube  Industry                         XI-2
               Synthetic  Rubber  Industry                            XI-2

  XII   ACKNOWLEDGEMENTS                                         XI1-1

 XIII   REFERENCES                                               XII 1-1

  XIV   GLOSSARY                                                  XIV-1

   XV   METRIC UNITS AND CONVERSION FACTORS                        XV-1
                                 VI

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                                                                      DRAFT
                                  FIGURES
Figure No.                      Title                            Page No.

  I I 1-1          Flow Diagram for Typical  Tire and
                    Camelback Production Facility                 I I 1-8

  I 11-2          Flow Diagram for a Typical  Inner Tube
                    Production Facility                           111-16

  I 11-3          General Water Flow Diagram for an Emulsion
                    Polymerized Crumb Rubber Production
                    Facility                                      111-22

  III-**          General Water Flow Diagram for a Solution
                    Polymerized Crumb Rubber Production
                    Facility                                      111-28

  I I 1-5          General Water Flow Diagram for an Emulsion
                    Latex Rubber Production Facility              111-33
   IV-1          Location of Tire Manufacturing Plants,
                    Production Greater than 20,000 Units/Day,
                    and Synthetic Rubber Production Plants,
                    Production Greater than 60,000 Long Tons/
                    Day, Within the U.S., 1972        "            IV-1*

  VI1-1          Plant J:  Chemical Coagulation and Clarifi-
                    cation Plus Sludge Handling System Followed
                    by Bio-Oxidation Treatment                    VM-17

  VM-2          Plant K:  Air Flotation and Bio-Oxidation
                    Wastewater Treatment Facility                 VII-20

  VI1-3          Plant N:  Activated Sludge Wastewater
                    Treatment Facility                            VI1-2?

   IX-1          Hypothetical Wastewater Segregation and
                    Treatment Facility for Tire and Inner
                    Tube Plants                                    IX-3

   IX-2          Hypothetical End-of-Pipe Secondary Wastewater
                    Treatment Facility for Synthetic Rubber
                    Plants                                         IX-6

   X-l            Hypothetical End-of-Pipe Advanced Wastewater
                    Treatment Facility for All  Sub-categories
                    of Synthetic Rubber Plants                       X-3
                                      vil

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                                                                     DRAFT
                                 TABLES

Table No.                       Title                             Page No.

 I I 1-1          U.S. Tire and Inner Tube Production from
                   1967-1971                                       I I 1-6

 I I 1-2          Summary of Potential Process-Associated
                   Wastewater Sources from the Tire and
                   Inner Tube Industry                             111-14

 I I 1-3          U.S. Synthetic Rubber Production by Type
                   for 1967-1971 and the Projected Growth
                   Rate to 1980                                    I M-18

 I I 1-4          Families of Synthetic Rubbers Included in
                   SIC 2822, Polymerization Processes, and
                   Annual U.S. Production (1972)                   111-20

 IM-5          Summary of Potential Process-Associated
                   Wastewater Sources from Crumb-Rubber
                   Production via  Emulsion Polymerization
                   Processing                                      I 11-26

 I I 1-6          Summary of Potential Process-Associated
                   Wastewater Sources from Crumb-Rubber
                   Production via  Solution Polymerization
                   Processing      .                               111-31

 I I 1-7          Summary of  Potential Process-Associated
                   Wastewater Sources from Latex Production
                   via Emulsion  Polymerization  Processing          I I 1-35


  IV-1          Major Tire  Production Facilities in the
                   United States                                    IV-3

   V-l          Raw Waste Loads  of Untreated  Effluent  from
                   Tire and  Inner  Tube  Facilities                     V-2

   V-2          Average Values of  Raw Waste Loads  for  Tire
                    Industry                                           V-4

   V-3          Raw Waste Loads  of Process Wastewaters from
                   Tire and  Inner  Tube  Facilities                     V-5
                                     viii

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                                                                        DRAFT
                                   TABLES
                                 (Continued)

 Table No.                        Title                              Page No.

   V-4            The Sources and Characteristics of Process
                     Wastewaters from the Tire and Inner
                     Tube  Industry                                      V-6

   V-5            Raw Waste Loads for Emulsion Crumb Rubber
                     Plants                                             V-8

   V-6            Raw Waste Loads of the Principal Individual
                     Wastewater Streams in an Emulsion Crumb
                     Rubber Plant                          "             V-10

   V-7            Raw Waste Loads for Solution Crumb Rubber Plants      V-12

   V-8            Raw Waste Loads for Latex Rubber Plants               V-15

 VI 1-1            Wastewater Control and Treatment Technologies
                     at Exemplary Tire and  Inner Tube Plants          VI1-2

 VI 1-2            Wastewater Control and Treatment Technologies
                     at Exemplary Synthetic Rubber Plants             VI1-3

VI I 1-1            Estimated Wastewater Treatment Costs
                     - Old Tire and Inner Tube                       VI 11-3

VI I 1-2            Estimated Wastewater Treatment Costs
                     - New Tire                                      VI 11-4

VIM-3            Estimated Wastewater Treatment Costs
                     - Emulsion Crumb Rubber                         VI I 1-10

VIII-U            Estimated Wastewater Treatment Costs
                     - Solution Crumb Rubber                         VI I 1-13

VI11-5            Estimated Wastewater Treatment Costs
                     - Latex Rubber                                  VI I 1-15
                                        ix

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                                                                    DRAFT
                            SECTION I

                           CONCLUSIONS
Two major and distinct categories exist within the rubber processing
industry:  1) the tire and inner tube industry; 2) the synthetic rubber
industry.

For the purpose of establishing limitations, the tire and inner tube
industry has been sub-categorized according to the age of the production
facility.  Waste  loads and costs of control technologies substantiate
this.  Factors such as the manufacturing process, final product, raw
materials, plant  size, geographic location, air pollution equipment,
and the nature and treatability of wastewaters do not justify further
sub-categorization of this industry group.

Process wastewaters for both sub-categories of the tire and inner tube
industry include  discharges of solutions used  in the manufacturing pro-
cess, washdown of processing areas, run-off from storage areas, and
spills and leakage of cooling water, steam, processing solutions, or-
ganic solvents and  lubricating oils.  Primary  pollutants in these
wastewaters  are oil and grease and suspended solids.

In the tire  and  inner tube industry, the emphasis of present environ-
mental quality control and treatment technologies is placed on the
control of particulate emission and the reduction, of pollutants  in
non-process  wastewaters.  Control and treatment of many process waste-
waters has been given secondary priority.   As  a result, no adequate
overall control and treatmen technology is  employed by plants within
the  industry.  A  treatment system, practicable and available to  the
industry, has  therefore been proposed for  both sub-categories.   It
encompasses  a  combination of the  various  technologies  employed by
the  different  segments of the  industry  to  control one  or more con-
stituents  in the  process  wastewaters.

Proposed effluent limitations  and standards for  the best practicable
control  technology  currently available  (Level  1)  are:

               Suspended  Solids      0.064 kg/1000  kg  raw material
               Oil  and Grease        0.008 kg/1000  kg  raw material

No  additional  reduction  is proposed  for Level  II  limitations and
standards  or  for new sources  coming on stream after  the guidelines
are  put  into effect.
  NOTICE:  THESE  ARE  TENTATIVE  RECOMMENDATIONS  BASED  UPON  INFORMATION
   IN THIS  REPORT  AND  ARE  SUBJECT TO  CHANGE  BASED  UPON COMMENTS  RECEIVED
  AND  FURTHER  INTERNAL REVIEW BY EPA.
                                1-1

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                                                                   DRAFT
For the purpose of establishing effluent limitations guidelines  and
standards of performance, the synthetic rubber industry has  been
sub-categorized, on the basis of processing techniques, product  type,
and wastewater characterizations, into three separate sub-categories:

               1.  Emulsion crumb
               2.  Solution crumb
               3.  Latex

All three sub-categories generate wastewaters which contain  the  same
constituents.  However, the concentration and loading of these con-
stituents, termed "raw waste load", vary between the sub-cateogories.
The significant wastewater constituents are COD, BOD, suspended  solids,
and oil and grease.  Latex production wastewaters, although  lower in
flow per unit of production than the other two categories, have  the
highest raw waste  loads.

The wastewater parameters selected to be the subject of the effluent
limitations are COD, BOD, suspended solids, and oil and grease.   These
parameters are present  in the wastewater as a result of organic  con-
tamination.  Heavy metals or toxic materials were not found in
significant quantities  in synthetic rubber wastewaters.

Existing control and treatment technology, as practiced by the  industry,
emphasizes end-of-pipe  treatment rather than in-plant reductions.  This
is because in-plant modifications which might lead to  improved waste-
water management appear to adversely affect processing techniques or
quality of the final product.

Current treatment  technology for both emulsion crumb and  latex plants
involves primary clarification with chemical coagulation of latex
solids, followed by biological treatment.  As an alternative to chemi-
cal coagulation, air flotation clarification of primary and secondary
solids  is successfully  practiced.  Biological treatment systems   in-
clude activated sludge  plants and aerated  lagoon and stabilization
pond systems.  Level I  control .and treatment technology for emulsion
crumb and  latex plants  has been  defined as equivalent to chemical
coagulation and biological treatment.

Current treatment  technology for solution crumb requires conventional
primary clarification of  rubber  solid fines followed by biological
treatment.  Existing biological  treatment systems employ aerated  lagoon
and stabilization  pond  systems or activated sludge plants.  Level 1
control and treatment technology for solution 'crumb  production  facili-
ties has been defined as  equivalent to primary clarification and
biological treatment.
 NOTICE:  THESE ARE TENTATIVE RECOMMENDATIONS BASED UPON INFORMATION
 IN THIS REPORT AND ARE SUBJECT TO CHANGE BASED UPON COMMENTS RECEIVED
 AND FURTHER INTERNAL REVIEW BY EPA.

                                1-2

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                                                                   DRAFT
Level II technology for the three sub-categories has been defined as
equivalent to dual-media filtration followed by activated carbon treat-
ment of the effluent from the biological treatment system to achieve
acceptable COD removal.  The applicability of this technology for
Level II is based on very limited data.  The performance capabilities
of the proposed Level  II treatment systems must be confirmed by further
testing and evaluation before approval of this document.

Level III control and treatment has been defined as identical to
Level II; that is, equivalent to activated carbon adsorption treatment
of the secondary effluent.

The proposed effluent  limitations and standards of performance for
plants within the three synthetic rubber sub-categories can be sum-
marized as follows, expressed as kilograms of pollutant- per 1,000
kilograms of production:

                             Level 1

                   Emulsion Crumb       Solution Crumb       Latex
                       Plants               Plants          Plants

                    kg/1,000 kg          kg/1,000 kg     kg/1,000 kg

  COD                   8.00                 3.94            6.85
  BOD                   0.40                 0.40            0.34
  Suspended solids      0.65                 0.65            0.55
  Oil and Grease        0.16                 0.16            0.14
                     Level I I  and Level I 11

                   Emulsion Crumb       Solution Crumb       Latex
                       Plants               Plants          Plants

                    kg/1,000 kg          kg/1,000 kg     kg/1,000 kg

  COD                   2.08                 2.08            1.78
  BOD                   0.08                 0.08            0.07
  Suspended Solids      0.16                 0.16            0.14
  Oil and Grease        0.08                 0.08            0.07
NOTICE:  THESE ARE TENTATIVE RECOMMENDATIONS BASED UPON  INFORMATION
IN THIS REPORT AND ARE SUBJECT TO CHANGE BASED UPON COMMENTS RECEIVED
AND FURTHER INTERNAL REVIEW BY EPA.

                               1-3

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                                                                   DRAFT
                           SECTION II

                         RECOMMENDATIONS
Implicit in the recommended guidelines for the tire and  inner  tube
industry is the fact that process wastes can be isolated  from  non-process
wastes such as utility discharges and uncontaminated storm  runoff.   Segre-
gation of process sewers is therefore the first recommended step in  the
accomplishment of the reductions in oil and suspended solid loading  neces-
sary to meet the guidelines.  Treatment of process wastewaters in a  com-
bined process/non-process system is ineffective due to dilution by  the
relatively large volume of non-process wastewaters.

It is further suggested that uncontaminated waters, such as storm run-
off, be segregated from outdoor areas where the potential exists for
contamination by oil or solids.  This would include roofing and curb-
ing of storage areas and the collection and treatment of runoff which
cannot be isolated from such areas.

The training of operators and maintenance personnel is important in
any control  technology.  Negligent dumping of various processing solu-
tions and lubricants  into unsegregated drains within the plant must be
eliminated or at  least severely diminished.  Washdown of potentially
contaminated areas must be eliminated whenever possible.  The number
and  location of  in-plant drains should be kept at a minimum, to reduce
the possibility of process wastewater contamination to as few sources
as possible.

Wet air-pollution equipment should be  kept  to a minimum.  Discharges
from wet equipment already  in  service  should be recycled when possible.
The use of dry-type  pollution  equipment  is  consistent with recovery
efficiencies and  prevention of wastewater control  problems.

In-plant modifications which will  lead  to  reductions  in  wastewater
flow,  increased  quantity of water  used  for  recycle  or reuse, and im-
provement  in  raw  wastewater quality  should  be  implemented providing
that  these modifications have  minimum  impact on processing techniques
or product quality.

End-of-p!pe treatment technologies equivalent  to  secondary treatment
should  be applied  to the wastewaters  from  all  synthetic  rubber  sub-
categories to  achieve Level  I  standards.   For  emulsion crumb and latex
plants, chemical  coagulation and  clarification should be provided prior
to  secondary  treatment.
 NOTICE:  THESE ARE TENTATIVE RECOMMENDATIONS BASED UPON INFORMATION
 IN THIS REPORT AND ARE SUBJECT TO CHANGE BASED UPON COMMENTS RECEIVED
 AND FURTHER INTERNAL REVIEW BY EPA.

                              II  - 1

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                                                                   DRAFT
To achieve Level II standards, end-of-pipe treatment technologies  equiva-
lent to activated carbon adsorption of secondary treatment  effluent  is
required on all wastewaters originating in synthetic rubber plants.

Confirmatory tests are necessary to insure that activated carbon adsorp-
tion is applicable to secondary effluent wastewaters from synthetic
rubber plants.  These tests should be performed and evaluated  prior
to approval by EPA of this document and its findings.

The evaluation of carbon adsorption techniques on synthetic rubber plant
wastewaters should include investigation into the character of the re-
fractory or non-biodegradable portion of the organics in the raw waste
load.  These investigations should be aimed at minimizing their presence
in the wastewater as well as changes in their chemical or molecular
structure to make them amenable to biological oxidation or  alternative
treatment or removal methods.

Level  III control and treatment standards, to be applied to new sources,
are identical  to Level  II for all synthetic rubber sub-categories; that
is, equivalent to activated carbon treatment of secondary treatment
effluent.

The treatment, control  theory, and effluent guideline recommendations
for non-process wastewaters,  such as boiler blowdowns, cooling tower
blowdowns, and water treatment plant wastes,  in the  rubber processing
industry should be covered by the Steam - Electric Power Generation
and Water Treatment effluent  guideline documents or  by a separate EPA
study.
 NOTICE:  THESE ARE TENTATIVE  RECOMMENDATIONS BASED UPON INFORMATION
 IN THIS REPORT AND ARE SUBJECT TO CHANGE BASED UPON COMMENTS RECEIVED
 AND FURTHER  INTERNAL  REVIEW BY EPA.

                                11-2

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                                                                    DRAFT
                               SECTION I I I

                              INTRODUCTION
Purpose and Authority

Section 301(b) of the Act requires the achievement, by not later than
July 1, 1977. of effluent limitations for point sources (other than
publicly-owned treatment works) which are based on the application of
the "best practicable control technology currently available" as defined
by the Administrator pursuant to Section 304(b) of the Act.   This best
practicable control technology will be referred to as Level  I Control
and Treatment Technology.

Section 301(b) also requires the achievement, by not later than July 1,
1983, of effluent limitations for point sources (other than  publicly-
owned treatment works) which are based on the application of the "best
available technology economically achievable" which will  result'in
reasonable further progress toward the national goal of eliminating
the discharge of all pollutants, as determined in accordance with
regulations issued by the Administrator pursuant to Section  30Mb) to
the Act.  The best available technology economically achievable as
stated above will be called Level  I I  Control and Treatment Technology.

Section 306 of the Act requires the achievement by new sources of a
Federal standard of performance providing for the control of the dis-
charge of pollutants that would reflect the greatest degree of effluent
reduction which the Administrator determines to be achievable through
the application of the "best available demonstrated control  technology,
processes, operating methods, or other alternatives",  including, where
practicable, a standard  permitting no discharge of pollutants.  The best
available control technology for new sources as discussed above  is to  be
termed Level  I I I Control and Treatment Technology.

Section 30Mb) of the Act requires the Administrator to publish, within
one year of enactment of the Act,  regulations providing guidelines for
effluent limitations setting forth:

      1.  The degree of effluent reduction attainable through the ap-
         plication of the best practicable control technology currently
         available.

      2.  The degree of effluent reduction attainable through the ap-
         plication of the best control measures and practices achievable
          (including treatment  techniques, process  and  procedure  in-
         novations, operation  methods, and other alternatives).
                                  111-1

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                                                                   DRAFT
The regulations proposed herein set forth effluent limitations  guidelines
pursuant to Section 30A (b) of the Act for the tire and inner tube  and the
synthetic rubber subcategories of the Rubber Processing Industry.

Section 306 of the Act  requires the Administrator, within one year after
a category of sources is included in a list published pursuant  to  Section  306(b)
(1) (A) of the Act, to  propose regulations establishing Federal  standards
of performances for new sources within such categories.  The Administrator
published, in the Federal Register of January 16, 1973 (38 F.R.  162A) ,  a
list of 27 source categories.  Publication of the list constituted announce-
ment of the Administrator's intention of establishing, under Section 306,
standards of performance applicable to new sources within the tire and
inner tube and synthetic rubb'er subcategories of the rubber processing
industry which were included in the list published on January 16,  1973.

The guidelines in this  document identify (in terms of chemical,  physical,
and biological characteristics of pollutants) the level of pollutant
reduction attainable through the application of the best practicable con-
trol technology currently available (Level I), and the best available
technology economically achievable  (Level II).  The guidelines  also
specify factors which must be considered in  identifying the technology
levels and in determining the control measures and practices which are
to be applicable within given industrial categories or classes.

in addition to technical factors, the Act requires that a number of other
factors be considered,  such as the costs or cost-benefit study and the
non-water quality environmental impacts  (including energy requirements)
resulting from the application of such technologies.

Summary of Methods Used for Development of the Effluent
Limitations Guidelines  and Standards of Performance

The effluent  limitations guidelines and standards of performance proposed
herein were developed in a stepwise manner.

The development of appropriate industry categories and subcategories
and the establishment of effluent guidelines and treatment standards
require a sound understanding and knowledge of the rubber industry, the
processes involved, water use, recycle and reuse patterns, characteristics
of wastewater, the respective raw waste  loadings, and  the capabilities
of existing control and treatment methods.

Initial categorizations and subcategorizations were based on raw materails
used, product produced, manufacturing process employed, and other factors
such as plant age.  Published  literature was consulted to verify the raw
waste characteristics and treatabi1ities  in order to support the initial
industry categorizations and subcategorizations.
                                  111-2

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                                                                   DRAFT
The raw waste characteristics for each tentative subcategory  were  then
fully identified.  Factors considered in this analysis were:   the  supply
and volume of water used in the process employed; the sources of waste
and wastewaters  in the plant; and the constituents, including thermal,
of al 1  wastewaters together with those contaminants which are toxic
or result in taste, odor, and color in water or aquatic organisms.   The
constituents of wastewaters which should be subject to effluent  limitations
guidelines and standards of performance were identified.

The full range of control and treatment technologies existing within each
subcategory was  identified.  This involved an identification  of  each distinct
control  and treatment technology (including both in-plant and end-of-pipe
technologies) which are existent or capable of being designed for  each
subcategory.  It also included an identification in terms of  the amount
of constituents  (including thermal), the chemical, physical,  and biological
characteristics of pollutants, and the effluent level resulting  from the
application of each of the treatment and control technologies.   The  prob-
lems, limitations/reliability of each treatment and control  technology,
and the required implementation time were also identified.   In addition,
the non-water quality environmental impact, such as the effects  of the
application of such technologies upon other pollution problems (including
air, solid waste, noise, and radiation) was also identified.   The  energy
requirements of each of the control and treatment technologies were  iden-
tified as well as the cost of the application of such technologies.

The information, as outlined above, was then evaluated in order  to deter-
mine what levels of technology constituted the "best practicable control
technology currently available"  (Level  I), the "best available technology
economically achievable"  (Level  II), and the "best available  demonstrated
control  technology, processes, operating methods, or other alternatives
for new sources" (Level  III).  In identifying such technologies, various
factors were considered.  These  included the total cost of application  of
technology  in relation to the effluent  reduction benefits to  be  achieved
from such application, the age of equipment and facilities involved, the
process employed, the engineering aspects of the application  of  various
types of control technique process changes, the non-water quality  environ-
mental   Impact  (including energy  requirements), and other factors.

Raw wastewater characteristics and treatability data, as well as infor-
mation  pertinent to treatment reliability and cost evaluations,  were
obtained from several sources, including:  EPA research information,
published literature, Corps of Engineers Permit to Discharge  Applications,
industry historical data, and expert  industry consultation.   On-site
visits  and  interviews were made to exemplary tire, inner tube, and
synthetic rubber production plants throughout the United States  to con-
firm and supplement the above data.  All references used in  the  develop-
ment and preparation of the guidelines  for effluent  limitations  and
standards of performance, as  implied by Levels I,  II, and III Control
and Treatment Technologies, are  included in Supplement B to this document.
                                  111-3

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                                                                   DRAFT
General Description of the Industry

The categories of the rubber processing industry covered  by  this  docu-
ment are the tire and inner tube (SIC 3011) and the synthetic  rubber
(SIC 2822).  The manufacture of tires and inner tubes utilizes  completely
different processing techniques than the production of synthetic  rubber.
In a tire or inner tube plant, stock rubber production follows  a  very
definite formulation or recipe, and is a batching operation.

The mixed stock production is used to produce the four main  ingredients
of a tire:  tire beads, tire treads, treated fabric, and  cord  fabric.
These four components enter the tire building plant, where a significant
amount of hand and machine Igy-up is required to produce  the green tires.

The synthetic rubber (or vulcanizable elastomer) industry is characteri-
zed essentially by the chemical process and unit operations  necessary  to
convert the particular monomer or starting-block material into a  stabi-
lized, granulated, extruded, or baled material suitable for more  conven-
tional rubber processing.  The processes are characterized by  separation
of unreacted monomer, recovery, purification and recycle  of the monomer,
and processing of the converted elastomer.  These reactions are normally
carried out batch-wise or batch/continuous.

In view of the fact that these two  industry classifications, tire and
inner tube manufacture and synthetic rubber production, differ consider-
ably it is appropriate, from this point on, to describe and evaluate
their water uses and wastewater generations separately.

     Tire and Inner Tube Industry

          Tire Manufacture

There are many events that have had a significant effect on the tire and
inner tube  industry.  The first is  the discovery, by  Charles Goodyear in
1839, that  rubber could be cured or vulcanized with sulfur.  Thus,
Goodyear was able to overcome  the tacky, plastic properties of rubber,
thereby creating a product of  commercial applicability (1).

The year  1906 saw the development of the first organic accelerators.
Accelerators are substances which affect the  rate of  vulcanization.  With
the entry of such substances,  better products  could be produced in a
shorter period of time  (1,2).

The next major event to affect the  tire  industry was  the advent of the
Second World War.  With the drastic  reduction  in the  supply of natural
rubber, new sources had to be  developed.   The  first substitute was re-
claimed  rubber which, by  19^3, had  completely  replaced natural rubber
as  the basic tire material.   It was  not  until  the mid 19^0's that syn-
thetic rubber, made available  due  to a major  governmental effort, became
                                  MI-4

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                                                                   DRAFT
the major substitute for natural rubber.  By 19^5,  approximately  98  per-
cent of the natural rubber had been replaced by this synthetic  substi-
tute (3).  The years following the war saw the return,  to a  great extent,
of natural rubber.  However, with the technological  boost given the  syn-
thetic rubber industry, it would soon again become  the  larger portion of
the ti re.

The next major event occurred in the mid 1950's and concerned the intro-
duction of tubeless tires as original equipment on  new  cars.   The 1950's
ushered in the first tubeless tire, and major changes were made in tire
design.  Butyl rubber became a major constituent of automobile tires.
At the same time,  it sent the inner tube industry into  a rapid decline.
The total number of inner tube units produced declined  from over A9'
million in 1951* to under 25 million in 1955  (A).

The tire industry has had three eras of rapid expansion to coincide  with
these events.  The post World War I era (1916-1929) brought  the first
such development.  As the automobile and truck industry expanded, so did
the tire industry.  Large capacity tire plants were built in Ohio, Cali-
fornia, and New England.  The depression reversed this  trend however,
and it v/as not until World War  II created an increased  demand for tires
that the tire industry again began to expand.  New plants were erected
in Ohio, New England, and the South.  The third building expansion
started in the early 19&0's and  is still proceeding, again occurring
simultaneously with the expansion of the economy.

With the current expansion, tire companies are now located throughout
the United States.  Whereas the older plants of the first two expansions
are located  in the urban areas of Ohio, California, and New England, the
newer plants are being located  in rural areas with no particular emphasis
placed on georgraphy.

Today's tire manufacturer produces many types of tires  designed for a
multitute of uses.  General product categories include passenger, truck
and bus, farm tractor and implement, and aircraft.  Table I I 1-1 presents
a breakdown of these products for the last five years.

The key to the performance of all tires is the selection of the raw rubber
and compounding materials and the proportion of these materials  in any
particular part of the tire.  Basically, the tire consists of five parts,
namely:  the tread, the sidewall, the cord,  the bead, and the inner liner.
Each part has different service  requirements; therefore, each requires  a
different proportion of the raw materials.   For example,  longevity and
good traction are  requirements of the tread, whereas a  high degree of
flexibility  is the requirement  for sidewalls.  Basic tire ingredients  in-
clude synthetic  rubber, natural  rubber, various fillers, extenders and
reinforcers, curing and accelerator agents,  antioxidants, and pigments.

A wide variety of  synthetic rubbers are used inlcuding SBR, polybutadiene,
butyl, polyisoprene, and EPDM.  Of the  three categories of compounding
                                  111-5

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                                                      Table I I 1-1

                               U.S. Tire and Inner Tube Production (Including Retreading)
                                                     for 1967-1971
                                          Tires (in million units)
Year
1967
1968
1969
1970
1971
Passenger
Cars

100.006
128.967
134.540
123.356
138.151
Trucks and
Buses

21.165
25.533
27.211
25.680
28.461
Farm Tractor
and Implement

5.55^
5.741
4.058
3.568
4.099
Ai rcraf t

0.772
1 .040
0.892
0.822
0.731
Mi seel laneous
16.445
17.870
18.421
6.866
9.409
2
Inner Tubes
mi 1 1 ion units
60.479
65.840
60.875
51.534
55.067
Retreading
Rubber2
mill ion pounds
563.307
610.108
598.417
622.413
608.476
- Includes motorcycle, Industrial, garden tractor, and bicycle tires.
 Includes all  tire classifications.


 Source: "Rubber  Industry Facts", Statistical  Department,  Rubber Manufacturers  Association,  New York.

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                                                                   DRAFT
materials used, the fillers, extenders and reinforcers are  the most  im-
portant.  These are used:

     1.  To dilute the raw crumb rubber in order to produce a greater
         weight or volume.

     2.  To Increase the strength, hardness,  and abrasion  resistance to
         the final product.

Of this group, carbon black and oil are the most common.   A typical
rubber compound might be described as follows (1):

     100 parts rubber
     50 parts fillers, extenders, and reinforcers
     3.5 parts curing and accelerator agents
     8.0 parts antioxidants and pigments

The typical tire manufacturing process consists of the following:

     1.  Preparation or compounding of the raw materials.

     2.  Transformation of  these compounded materials into the  five tire
         components.

     3.  The building, mol-ding, and curing of the  final  product.

A flow diagram for  the typical plant  is shown in  Figure I I 1-1.

The basic machinery  units  used  in  the compounding  operation are the
Banbury mixer and the  roller mill.  A Banbury mixer  is a batch-type in-
ternal mixing device and  is the hub of this compounding operation.  The
Banbury  is used  for two operations.   In the first, the fillers, extenders
and reinforcing  agents, and the pigments  and antioxidant agents are added
and mixed  into the  raw rubber stock.  The resulting  mixture is known as
non-productive or non-reactive  rubber stock.  Because no curing agents
have been  added,  this  material will have  a  long  shelf life, thus allowing
large  quantities  of a  particular  recipe to be made and stored for  later
use.   In  the  second operation,  the curing and accelerator  agents,  in
additon  to a  small  quantity of  the original  list of  elements, are added.
This mixture,  known as productive  or  reactive  rubber stock, now meets
the particular compounding requirements of  its  final destination.   Since
it contains  the  curing agents,  this mixture has  a short shelf life  and
will be used  almost immediately.

Carbon black  and oil are  usually  added automatically in the compounding
operation.  The  other compounds  (including  the  raw rubber) are manually
weighed and  fed  to the Banbury.   The  reasons  for the automatic handling
equipment are:

      1.   The  large quantities  of these materials consumed.
      2.   To ease the maintenance and  housekeeping problems created  by
          both the oil  and carbon black.

                                  111-7

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                                                                    FIGURE  Ill-l
                             FLOW DIAGRAM FOR TYPICAL TIRE AND CAMELBACK PRODUCTION  FACILITY
                                                                                                                                INTAKE WATER
    i
WASTEWATER
  *
WASTEWATER
                                  LEAKAGES
                                  DIASHDOWN
SLOWDOWN

   I
WASTEWATER
REGENERATION
WASTE
    I

WASTEWATER
                                 •ASTEWATER

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                                                                    DRAFT
Carbon black is a finely divided amorphous material  that  has  the  con-
sistency of dust.  Once left unconfined, it creates  a massive air pol-
lution problem.  The compounding area is equipped with air pollution
equipment to control this problem.  Normal procedure is to use a  bag
house.

After mixing, the compound is sheeted out in a roller mill, extruded
into sheets, or pelletized.  The process depends on  the type of batch
(reactive or non-reactive) and the manufacturer.  Pelletizing of a non-
reactive batch enables the weighing and mixing of the reactive stock  to
be done automatically.  The reactive compounded rubber is always  sheeted
out.

The sheeted material is tacky and must be coated with a soapstone solu-
tion.  This solution is a slurry which, when allowed to dry on the sheet-
ed materials, prevents them from sticking together during storage.

Because it  is a slurry the soapstone solution is usually recirculated.
Releasing the material into a wastewater stream would create a difficult
solids problem.  Spills in the soapstone area are common and do create  a
maintenance and wastewater problem.

If a manufacturer wishes  to exclude soapstone in his final effluent,  he
must provide a method  for coping with these spills.   Current techniques
include the blocking of all drains  in the area, diking of  the area, and
the use of  steel grates on the floors.  The diking and sealing of drains
prevents the slurry  from  entering the drainage  system.  The  use of steel
grates helps decrease  the  risk of workers slipping on spilled soapstone.

Maintenance and housekeeping problems  in  this area are further compli-
cated by the leakages  of  oil and water  from the oil   seals  in the mills,
and oil and dust from  the dust ring  seals of  the Banburys.   Each has the
potential to become  a  wastewater  pollutant  if allowed to mix with the
cooling water  discharges  or to be washdowned  and discharged  without
treatment.

The  rubber  stock once  compounded  and mixed must be molded  or transformed
into  the form  of one of the  final parts  of  the  tire.  This consists of
several parallel processes  by which  the sheeted rubber and other  raw
materials,  such  as  cord and  fabric,  are  made  into the  following  basic
tire  components:   tire beads, tire  treads,  tire cords, and  tire  belt
 (fabric).   Tire  beads  are coated  wires  inserted in  the pneumatic tire at
the  point where  the tire  meets  the  steel  rim  (on which  it  is mounted);
they  insure a  proper (and possibly  air  tight) seal between  the  rim and
the  tire  (2).  The tire treads are  the  part- of  the  tire  that meets the  road
surface; their design  and composition  depend  on the  use  of the tire.
Tire  cords  are woven synthetic  fabrics  (rayon,  nylon,  polyester)  im-
pregnated with rubber; they  are  the body of  the tire and  supply  it with
most  of its stregth.  Tire belts  stabilize  the  tires,  prevent  the  lateral
                                  I I 1-9

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                                                                   DRAFT
scrubbing or wiping action that causes tread wear,  and reduce  heat  build
up, a major cause of tread wear (2).

In the formation of tire treads, the rubber stock as  it is  received from
the compounding section is manually fed to a warm-up  roller mill.   Here
the rubber is heated and further mixed.  Heat is provided  by the  con-
version of mechanical energy.  Temperature control  is provided by the
use of cooling water within the rolls of the mill.

The heated stock passes from the warm-up mill to a strip-feed  mill  where
it receives its final mixing.  This mill is also cooled to control  the
temperature of the stock.  The stock is peeled off the rollers of the
mill  in a thin strip which is. fed continuously to ah  extruder. The mix-
ing of the stock in these mills insures that the final tread will  have
homogeneous properties.  The heating or temperature control of the stock
is necessary to insure a proper extrusion with a minimum consumption of
power (2).

At the extruder, two types of rubber stocks originating from two-differ-
ent strip mills are joined together to form the tire tread and sidewalls.
The tread leaves the extruder as a continuous trip while still hot and
therefore tacky.  Next a cushioning  layer  is attached to the lower side
of the tread.  The tread is then cut to the proper width,  cooled  in a
water trough, labeled, cemented, and then  cut to the proper length.
Trimmings are either manually or automatically transferred back to the
proper strip-feed mill and reprocessed.  Having been cut,  the ends are
cemented, and the tread  is placed  in a "tread book" and sent to the tire
buiIding machines.

Wastewater problems  in this area arise  from the spillage of the solvent
base cements, from oil and water leakages  from the various mills, and
from accidental overflows from  the cooling water system.  The cooling
water overflow would not normally  be a  problem since the rubber tread is
relatively inert and therefore  does not contaminate the water.  However,
it does serve as a washdown agent  for  an area contaminated with the ce-
ments and oils.

To produce tire cords  and belts, rubber stock must be  impregnated onto a
pretreated fabric.   The  fabric  is  let  off  a  roll, spliced onto the tail
of the previous roll  (either adhesively or by a high-speed  sewing machine),
and  fed under controlled  tension  (via  a festooner) to  a latex dip tank.
After dipping and while  still  under  tension,  the fabric is  fed past vacu-
um suction  lines or  rotating beater  bars  to  remove the excess dip before
the  fabric  rises through  a drying  and  baking  oven.

After pretreatment,  and  still  under  tension,  the fabric is  passed  through
a  calendering machine  where  rubber is  impregnated  into the  fabric.  The
rubber  fabric  is next  cooled by large  water or  refrigerant  cooling drums;
after cooling,  the  tension can  be  released.   This  treated  fabric  is still
                                 111-10

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                                                                   DRAFT
not ready for the tire building operation.  To achieve the  proper bias
it must be cut to the proper angle and length, and then spliced  together
again.  The angle and length will vary depending on the size  of  the tire
for which it is used and whether it is a cord or belt.  Once  spliced  to-
gether, the fabric is rolled in cloth and sent to tire building.

The rubber used to impregnate the fabric proceeds through an  operation
similar to that of the tread process.  It passes through both a  warm-up
mill and a strip-feed mill prior to impregnation onto the fabric.  Waste-
water problems in this area arise due to the latex dripping operation
and to problems with oil and water leaks and spillages which  are similar
to those of the tread process.

Many tire manufacturers are transferring their latex dip operations from
individual plants to one  large central facility.  In most cases, the
reasons behind such a decision are as follows:

     1.  A minimal dipping operation  requires a large capital expenditure.

     2.  The fabric dipping and coating operation is one of the  fastest
         operations in the plant and, as such, is readily capable of
         over-supplying the plant with fabric.

     3.  Dipped fabric  is not that more expensive to ship then undipped
         fabric.

     4.  The maintenance  and housekeeping requirements of the dip oper-
         ation are limited to one  facility.

In  the processing of  rubber stock  to  tire beads, the  rubber  is extended
onto a series of copper-plated steel  wires,  then cemented,  wrapped,  and
cut.  The rubber stock  is pretreated, as before,  in a warm-up mill  and
strip-feed mill.  Excess  rubber  is trimmed  from the bead before it leaves
the extruder and  is fed back to  the strip feed mills.  To apply cement
the coated wire  is passed through  a trough  or set of  brushes.  The ce-
ment  is necessary to  insure the  proper adhesive of the bead when it   is
wrapped.

Wastewater  problems can arise  due  to  the  use of the mills or from the
spillage  or overflow  of the cement.   They will be  similar  in nature to
those  found  in  this  tread formation  process.

The inner  lining  of  the two  is  formed by  calendering  or  extruding the
rubber stock  in  a manner  similar to  either  the  formation of  cord fabric
or tread  rubber.   It  is this  inner liner  that enables  a  tire to be tube-
less  since  it  is  light  and  relatively air  impervious.

The tire  is built  up  as a cylinder on a  collapsible,  round rotating drum.
First the inner liner is  applied to  the  drum.   Then  layers of cord are
                                 111-11

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                                                                    DRAFT
 applied, one  layer  tying  the  beads together  in one direction and another
 layer  in the  other  direction.  The beads are stiched to the tire by
 folding over  the ends  of  the  cord fabric.  Next the tire belt fabric is
 laid onto  the cord.  Finally  the tire tread  is placed over the cords and
 fabric and wrapped  around the beads.  The cylinder is removed.  These
 green  tires  (uncured tires) are now  ready for final processing.

 Washdown of solvents from this area  can create a wastewater problem; how-
 ever,  this is normally dry and therefore very pollution free.  Before
 molding and curing, the green tire must be sprayed with release agents.
 These  agents  aid  in the release of air from  the tire during molding and
 of  the tire from the mold after curing.  Both water- and solvent-based
 spray  are  used.  Excess spray is released to the atmosphere.  Most plants
 now place  the tires in a  hood before spraying in order to meet federal
 air quality standards.

 The potential for wastewater  streams exist due to the possibility of sol-
 vent spills within  this area.  If wet scrubbers are used to scrub the ex-
 cess spray from the air,  another wastewater  stream will exist.  .

 The tire is molded  and cured  in an automatic press.  Here an  inflatable
.rubber bladder bag  is  blown up inside the tire, causing the tire to take
 its characteristic  doughnut shape.   The mold is simultaneously closed
 over the shaped tire.   Heat is applied by steam via the mold and bladder
 bag.   Excess  rubber and trapped air  escape through weepholes.  After a
 timed, temperature-controlled cure,  the press is cooled, the bladder is
 deflated via  a vacuum, and the tire  is removed.  The tire is next in-
 flated with air and left  to cool in  the atmosphere.  This last  inflation
 insures product quality and uniformity by allowing the tire to "set up"
 or  achieve the final  limits of its cure under controlled conditions.

 Because of the large number of presses in the typical plant,  there  is
 always the potential  for  a mold to leak or for a bladder to break.  This
 water  is released and  scavenges some of the  large amounts of  lubricating
 oil used in this area. This  oily water creates a water contamination
 problem  if it is discharged.

 After  the  molding and  curing  operations, the tire proceeds to  the grind-
 ing operation where the excess rubber which  escaped through the weepholes
 is  ground  off.   If  the tire is designated to be a whitewall, additional
 grinding is performed  to  remove a black protective strip.  More expen-
 sive tires receive  further grinding  of the tread  in order to  balance the
 tire.

 The weepholes which are ground off are relatively  large particles of
 rubber which  fall  to  the  floor and are swept up.  Their final  destina-
 tion  is a  landfill.  The  grindings from the  white sidewall operation are
 relatively small  and  will stay airborne for  long periods of time.  The
 industry generally  uses a particulate collection device such  as cyclone
                                 111-12

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                                                                    DRAFT
or wet scrubber to control these emissions.  The discharge  from a wet
scrubber will have a high solids content and will  therefore be a waste-
water problem.  The balancing operation suffers the same problems as  the
white sidewall grinding operation.

After the grinding operations, the wh'itewall portion of a tire receives
a protective coat of paint.  The paint is generally water based.  This
operation usually occurs  in a hooded area.  Again, any wet  air pollution
equipment or runoff due to over spraying of the paint will  create pol-
lution problems.  After inspection and possibly some final  repairs,  the
tire is ready to be shipped.

Table I I I-2 presents a review, of the potential sources of wastewater
streams as discussed above.

The discussion thus far has described a typical tire plant, and applies
most readily to the production of the passenger tire.  There are several
variations.  The first of these is due to the production of truck and in-
dustrial  tires.  Truck tires  tend to have a greater amount  of natural
rubber in their treads.   Natural rubber, as received in the plant, is
much harder to handle than synthetic rubber.  Additional roller mills
are needed to break up and soften the rubber before it enters the
Banbury mixer.  There are also major differences  in the building and
molding of the tires as the larger sizes are approached.  The building
of a "giant off-the-road  tire" requires the services of two men each for
a half a day, whereas the passenger tire can be built in less than 5
minutes.  Larger tires are cured  in giant molds which are not automati-
cally operated.  Cranes or hoists are required to open and close this
mold.  Curing can take up to  2k hours.  Hot water,  instead of steam, is
used in the curing operation.  The process variations associated with
truck and  industrial tire production do not have  a  significant effect on
the quantity and quality  of the wastewaters generated when compared to
those from automobile tire production.

Another variation in the  typical tire production  is the manufacture of
camelback.  Camelback is  tread used for tire  retreading  (2).   It  is pro-
duced in the  same manner  as tread used  for new tires'.   (See flow diagram,
Figure 111-1.)

Camelback  production operations are usually part  of a tire production
facility feeding off the  same machinery.  Wastewater problems will be
similar to those already  discussed.

Radial tire production offers another variation to  the overall process.
Radial tires,  like  truck  tires, contain more natural rubber,  thus re-
quiring more  machinery  in the compounding  area.   Whereas bias-ply tires
are built  in  the form of  a hollow cylinder,  radial  tires are  built in
the doughnut  shape  of the final product.   Like truck tires, radial tires
are cured  using  hot water instead of steam.  Again  wastewater problems
will be very  similar to  those of  the typical  passenger tire manufacture.


                                 111-13

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                                          Table IN-2

                       Summary of Potential Process-Associated Wastewater
                          Sources from the Tire and Inner Tube Industry
Plant Area

Oil Storage

Compounding
Bead, Tread, Tube
Formation

Cord and Belt
Formation

Green Tire Painting
Molding and Curing
Tire Finishing
Source

Run off

Washdown, spills, leaks,
discharges from wet air
pollution equipment
Washdown, spills, leaks
Washdown, spills, leaks
Washdown, spills.air
pollution equipment
Washdown, leaks
Washdown, spills, air
pollution equipment
Nature and Origin of Wastewater Contaminants

Oil

Solids from soapstone dip tank
Oil from seals in roller mills
Oil and solids from Banbury seals
Solids from air pollution equipment discharge

Oil and solvent-based cements from the cementing operation
Oil from seals in roller mills

Organics and solids from dipping operation
Oil from seals, in roller mills, calenders,  etc.

Organics and solids from spray painting operation
Soluble organics and solids from air pollution
equipment discharge

Oil from hydraulic system
0 i1 from presses

Solids and soluble organics from painting operation
Solids from air pollution equipment discharge
                                                                                                             o
                                                                                                             30

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                                                                   DRAFT
          Inner Tube Manufacture

Inner tube manufacture is very similar to tire manufacture in  that  the
process consists of the following steps:

     1.  Preparation or compounding of the raw materials.
     2.  The extension of these compounded materials to form a tube.
     3-  The building, molding, and curing to form the final  product.

A flow diagram for the typical process is shown in Figure  I I 1-2.

The basic machinery used in the compounding operation is identical  with
that used in the tire manufacture, namely, Banbury mixers  and roller
mills.  Both non-reactive and' reactive stocks are used.  Differences
arise since inner tubes are manufactured primarily from butyl  rubbers.
In addition, a soap rather than a soapstone solution is sometimes used
to coat the non-reactive stock.  Wastewater problems arising from this
section are identical to those of the typical tire compounding area,
i.e.,  leakages and dripping of oily and particulate material.

The process by which  the tube  is formed  is similar to the extrusion of
the tread.  The compounded rubber is  fed to an extruder via a warm-up
mill and strip-feed mill.  Here the rubber is extruded  into a continuous
cylinder, after which it is cooled and  labeled.  To keep the  inside of
the tube walls from sticking  to each  other, a dry soapstone powder is
sprayed  inside the tube as it  is formed  in the extruder.  After cooling,
the water is blown out of the  tube and  the same powder  is sprayed on the
outside of the tube.  Excess  powder must be collected  in each dry or wet
collection device.   If a wet  collection  device  is used, the discharge
will be heavily  laden with solids.  Other wastewater problems are simi-
lar to those found  in the tread  formation process of tire manufacture.

Once extruded, the tube must  be cut to  length and the ends spliced to-
gether.  A valve must also be attached.  There  is no potential waste-
water  problem  arising from this area  of operation.

Once  formed, the  tube must be molded  and cured.  Again, this  operation  \s
very  similar to  that  of  the  tire  manufacture.   Wastewater problems in-
clude  only water  leakage and  spills.

After  curing,  the tube  is  inspected  for defects,  packaged and sent to
warehousing and  shipping.  Table  I I I-2  summarizes  the  potential  sources
of wastewater  streams as discussed above.

      Synthetic Rubber Industry

           General

 The synthetic  rubber industry is responsible for the sythesis of vulcan-
 izable elastomers by polymerization  or co-polymerization  processes.  For
                                 II1-15

-------
CARBON

BLACK

STORAGE
                                    FIGURE  1U-2
        FLOW DIAGRAM FOR A TYPICAL INNER TUBE  PRODUCTION FACILITY
COOLING WATER
RETURN 1
COOLINR
^ COOLING WATER irr^ TOWER
SLOWDOWN
1


COOLING WATER
ror » TUC UT

1
1
1
REGENERATION
WASTE
I


RAW INTAKE
WATER

                                      WASTEWATER
                                                        WASTEWATER

RUBBER
AND QRY
COMPOUND
STORAGE

EXTENDER
OIL
STORAGE
SPI'LLS
RUNOFF
I
+
KASTEfATER
-6

\


COMPOUNDING:
R1W
n/itinunY -_--_.
MILLS STOCK
1 L+400L
I
4i LEAKAGE _WB..T
WASKOOWN
SOAP AND
SOAPSTONE
SOLUTIONS
\
SPILLS
LEAKAGE
WASHDOWN
WASTEWATER
TUBE FORMATION
MILLS
"* EXTRUDER UHCUR
COOLING Tt,orc
TANKS TUB£S
NG " [
j
EWATER • Bftiit-^
LEAKAGE WATER
T WASHnOWN
COOLING 1
WATER '
T
WASTEWATER
SUPP
~« *\
STEA*

TUBE
EO ^ SLICING
AND
CURING

— «C» INSPECTION —
PACKAGING


PRODUCT
M» STORAGE
AND
SHIPPIH9
fl$]
I VSTEAM
LEAKAGE
WASHDOWN
BOILER
V
(
BLOWOOWN
i
WASTEWATER
CONOENSATE
RETURN
i
4 MTFR
TREAT

A R**
KENT INTAKE
REGENE'RATION WTER
WASTE}
WASTEWATER

-------
                                                                   DRAFT



the purpose of this classification, an elastomer is a rubber-like ma-
terial  capable of vulcanization.

The U.S. Synthetic Rubber  Industry was fostered by the commencement of
World War II when it was realized that supplies of natural  rubber could
be shut off by the enemy.  The  rubber first chosen for production was
called GR-S (Government Rubber-Styrene) and would now be grouped under
SBR  (styrene-butadiene rubber).  Since the war the price of natural
rubber has been subject to great fluctuations, whereas the price stabili-
ty of synthetic rubbers has undoubtedly contributed to their acceptance
by the consumer.  Since the introduction of GR-S, many new synthetic
rubbers have been synthesized and produced on a commercial  scale.

The  demand for the various types of synthetic rubber  is greatly affected
by the needs of the tire manufacturers.  Not only are tire sales  impor-
tant, but process and product changes within the tire industry also in-
fluence the relative demands  for the various rubbers.  For example,
radial tires at present contain considerably more natural rubber  than
conventional tires.  At this  moment, this has little  effect on the con-
sumption of synthetic  rubber  because radial tires constitute a small
percentage of  total tire production, but  it does  illustrate the kind of
factor which can  influence synthetic rubber consumption.  The U.S. pro-
duction of  the principal synthetic  rubbers  for  the  last several years
is presented  in Table  I I I-3  together with  the growth  projections  for the
period  between now and  1980.   it can be  seen  that  production of  SBR-type
rubber overshadows other synthetic  rubber.  Although  the greatest growth
rates over  the next  several years  will  be  associated  with polyisoprene^
and  ethylene-propylene  terpolymer  (EPT)  productions,  overall the  relative
levels  of  synthetic  rubber production  will  not  be  appreciably different
from what  they are  today because  the  present  base  productions of polyisoprene
and  EPT are considerably  lower than that of SBR,  the principal  synthetic
rubber  (5).   This supports the assumption  that  there will be no radical
changes  in  the industry,  its  products, and even its production  processes
in the  foreseeable  future.

The  synthetic rubbers  as listed under  SIC  2822 include  both  the so-
called  tire rubbers  and the specialty rubbers.   The tire  rubbers are
typically  high production  volume commodities,  and,  as their  name suggests,
they are  used predominantly by the tire industry.   Rubber  used  in the
tire industry is supplied in a solid form termed crumb  rubber.   Several
different  families of tire rubber are made in order to  provide  all the
essential  and varying properties required in a modern vehicle  tire.

Not all  tire  rubber production is used in tire manufacture  however.
Much is used  to manufacture rubber hose, belting, electrical wire and
 cable, footwear, mechanical  rubber goods, and many other rubber-based
 products.  Due to their superior oil and heat resistance,  both  nitrile
 and neoprene  type rubbers are  used more for hose, seals, gaskets, and 0-
 rings than for tire manufacture.   However, because their annual production
                                  111-17

-------
                                                  Table  II1-3
                        .U.S.  Synthetic Rubber  Production  by Type  (1,000  Long Tons)  for
                               1967 to 1971  and the  Projected  Growth  Rate to  1980
                                                                                   Ethylene






—
1
00
Years

1967
i r\£.Q
19&0
1969
1970

1971
S-Type

1 ,244

1 ,389
1,403
1,331

1,417
Butyl
11/1
MH
11 o
13
130
118

106
Nitrile

62

'
69
67

65
Polybutadiene
9D1
i.\j i

217
263
280

254
Polyisoprene Pi


____________ i lin_.

109
120

117
•opy lene




75
63

60
Misc.
186

9fi1

201
218

222
Total
1 Q1 9
1 >y > <-
•) i -Ji
t- 1 1 j <
2,250
2,197

2,241
Projected Growth
                               2.7
5.2
7.0
16.0 to 1975
 8.0 to 1980
16.0 to 1975
10.0 to 1980
 Includes Polychloroprene (Neoprene)  rubber

Sources:   Production data from "Rubber  Industry  Facts",  Statistical Dept., Rubber Manufacturers Association.

          Growth rate production furnished by  Chem System,  Inc., New York.

-------
                                                                    DRAFT
volume is comparable with four of the other five major synthetic rubbers
used in tire manufacture, they will be considered here as tire rubbers.
The tire rubbers are grouped into seven families based on their monomeric
ingredients as shown in Table III-A.  The annual U.S. production,  poly-
merization process, principal end-use and other family members are also
presented.

By contrast, the speciality rubbers are low production volume commodities
with more diverse compositions and end uses.  The largest production
volume family of the speciality rubbers are the butadiene rubbers.
Butadiene rubbers are generally sold in latex form.  The production is
similar to the production of all synthetic rubber latexes (2).  Epi-
chlorohydrin is solution polymerized with various co-polymers to produce
the family of epichlorohydrin rubbers.  The process  is similar to that
for solution tire rubbers.  Epichlorohydrin rubbers  are.used for seals,
gaskets, and 0-rings, etc.  (6).  The acrylic rubbers are produced by an
emulsion polymerization process similar to the emulsion processes used
for drive-train and axle seals, hose, tubing, and molded parts.  Poly-
isobutylene is produced by  a solution polymerization process similar to
that for butyl rubber  (l).   It  is used primarily as  a blend  in caulking
compounds, adhesives, and plastics.

Three of the so-called specialty rubber families  (silicone rubbers,
urethane  rubbers, and fluorocarbon  derivative rubbers) are being  studied
as part of  the plastics  industry and, as such, are not covered  in this
document.  The chlorinated  and  chlorosulfonated polyethylene  rubbers are
manufactured by processes similar to those employed  for  the  polyethylene
type plastics and are not covered  in this document  (2).  The polysulfide
rubbers are produced by a condensation process which is  different from
the general emulsion and solution polymerizations  (2).   In addition,  the
wastewaters generated by polysulfide production are  highly contaminated
and deemed more difficult to  treat  than the wastewaters  produced  by con-
ventional emulsion or solution  polymerization processes.   It is therefore
recommended that a separate study be made of  the  polysulfide rubber sec-
tor of the  synthetic rubber industry.

The various methods of production  of the synthetic  rubber  have  much in
common.  The monomers are not  particularly  difficult to  handle  at  reason-
able pressures, and suitable  inhibitors have  been  developed  to  impart
storage  stability.  Dissipation of  the heat of  polymerization is  frequent-
ly  the controlling consideration.   Adjustment of  reaction  rate  to dis-
tribute  the heat generation over a  reasonable  period of  time,  the use of
refrigeration  cooling, and  operation  in dilute  media such  as emulsions
or  solutions  are necessary  for the adequate control  of  polymerization re-
actions.

Control  of  molecular weight and of molecular  configuration  has  become
a very  important quality consideration.  The  ability to control molecular
weight  has  led  to  the  development  of oil-extended rubber.   It has been
found  that  rubber  of  unusually high molecular weight and normally too


                                 111-19

-------
Principal Synthetic Rubber
Ti re Rubbers
,ren*-Butadiene rubbers  ionitri le-Butad iene rubbers (Nitrile)
1 > chl crop rene rubber (Neoprene)
Tire Rubber Sub-Total:
Specialty Rubbers
t a client rubbers
'cMorshydrin rubber
r, 1 !c rubbers
1 icone rubbers
lyurethane rubbers
3
l+
lysulfide rubbers
Specialty Rubber Sub-Total
Synthetic Rubber Total
Annual U.S. Production
(1 ,000 Metric Tons/year)
1.678
!39
368
139
163
169
159
177
2,992
6A
9
2
U
10
14
1
15
10
129
3J2I

Process
Emu 1 s t on
Solut ion
Solution
Solut i on
Solution
Solut ion
Emu Is ion
Emulsion
Emulsion
Solut ion
Enu 1 S i on
Solution
Condensat ion
Condensat ion
Emu Is ion
Post-polyrnertza-
t ion chlor inat ion
Condensation
Principal End-use Other Family Members
Genera) tire use
Tire treads
Tire treads
Tire treads
Inner tubes
General tire use, non-tire EPDH
goods
Hose, seats, gaskets,
0-rings
Chloroprene rubber
Adhesives, dipped goods, Pyr idine-Butadiene
paints rubber

Caul king, adhesives ,
plast ics
cat tape
Solid tires, rollers, Adiprene, Estane, 1 so-
foams, fibers cynate type rubber
Seals, gaskets, 0-ring, Viton, Ftuoro rubber
high temperature service
Wire and cable, shoes. Chlorinated rubber,
linings, paints Hypalon
Sealing, glazing, hose Thiol
* I though Nitrite and Neoprene-type  rubbers  are  not normally termed tire rubber, they are relatively large production volume  rubbers  and,  for convenience.

can be included with the major  tire  rubbers.

Silicone. Polyurethane and Fluorocarbon  derivative rubbers are considered part of the Plastics and Synthetics Industry and are not  covered  by  this

document.
Chlorosulfonated  and  chlorinated  polyethylenes  should be considered part of the Plastics and Synthetics Industry.  They are not covered b, this

document.

 Polvsulfide   rubbers  are  produced by a condensation-type reaction vAich is not directly comparable to either emulsion or solution  polymerization.
 Per unit  of  rubber  production,  generated wast.~aters are of considerably poorer quality and more troublesome to  treat than those of e.ther emuls.on
 or solution  or solution processes.    Polysulfide rubber production  is not covered by this document.   It is recommended that , separate study be mad.
 of the ool ysu If i de  rubber  industry.

 Source:   "The Rubber  Industry Statistical Report" - C.F. Ruebensaal, International Institute of Synthetic  Rubber Producers, Inc.

-------
                                                                   DRAFT
tough to process through factory equipment can be made workable  by  the
addition of up to 50 parts of petroleum-base oils per 100 parts  of  rubber.
These extending oils make the rubber easier to process without sacrifice
in physical properties.  Another improvement has been the preparation of
black masterbatches, the name given to mixtures of carbon black and rubber
without the curing ingredients.  This process is of great importance to^
small manufacturers and tire retreaders who lack facilities for mixing  in
carbon black or who wish to avoid atmospheric pollution with the fine
black.

          Synthetic Rubber Production

               Emulsion Crumb Production

Of the several methods of polymerization  employed  to  produce synthetic
rubber, the two most commonly used  processing techniques are polymerization
in homogeneous solution and  polymerization  in  emulsion.  Solution polymer-
ization may be considered to  include  bulk polymerization where  excess
monomer serves as  a solvent.  Emulsion  polymerization may be considered
as the bulk polymerization of droplets  of monomers suspended  in water.
Emulsion polymerization  is performed  with sufficient  emulsifier to main-
tain  a stable  emulsion.   Solution  polymerizations  generally proceed by
ionic mechanisms.   However,  polymerization initiators which operate by
ionic mechanisms  are  usually  too reactive to be stable in water; there-
fore, emulsion  polymerization  systems are initiated by agents which pro-
duce  free  radicals (2).

Emulsion polymerization  is  the  traditional process for the production of
synthetic  rubber.   Since World'War II (and for the foreseeable  future),
the  bulk of synthetic rubber has been produced via emulsion  polymerization.
The  use of emulsion polymerization systems is common because both  high
conversion rates and  high molecular weights are possible.   In addition,
other advantages are:   a high rate of transfer of the heat of polymer-
 ization through the aqueous  phase, ready  removal of unreacted monomers,
 and  high fluidity even at high concentrations of polymer.   The majority
of stvrene-butadiene rubber (SBR), the principal synthetic rubber, is
 produced by emulsion polymerization.  The emulsion polymer,zation  process
 Is used to produce either rubber latex or rubber crumb.  Crumb is  solid
 and  is usually formed into 75 pound  bales.

 Figure 11  1-3 shows a generalized materials  flow diagram for the continu-
 ous  production of crumb SBR by  the emulsion polymerization Process.  This
 schematic  is essentially typical of  all  emulsion  processes.  In the typi-
 cal   production facility, operation is  2k hours  per day, 365 days per
 year  Each plant consists of several  production  1•"« where d,fferent
 process recipes can be applied  and various  types  of  SBR can be produced,
  including non-extended, oil extended,  and carbon  black masterbatch van-
 eties.
                                  I 11-21

-------
                                                           FIGURE 111-3
     GENERAL WATER  FLOW  DIAGRAM FOR  AN  EMULSION  POLYMERIZED CRUMB RUBBER PRODUCTION FACILITY
        5lE«ATER

TREtTED PROCESS
•HER
                                                                                                             sir  «
                                                                                                             SUPPLt     +
                                                                                                                   »*STEIHE«
EQUIPMENT ^ CLEANUP  ^
     »»STE*HER     »»STE»»TEB
                                       EXTENDER OIL
                                          CARBON  BIACH SURRT
fOUIPKEKT'CLEAKUP
       I

      I
  »*STE»»TER
                                                                                                      LIVE
STEU
                                                                               CONOENSIITE
                                                                                                  TREATED
                                                                                                  PROCESS
                                                                                                  IITER
                                                  SUPPLY
                                                  STREM


It
BOILER
HOUSE
1
IUN
i
*e
I i
J
LER FEED WATER
>
t
VATER RAW INTAKE
UK ITS "U*
                                                                      BLONDOm
                           vurEimrEii
                                                                        Ei»l
                                                                                                          REGENERMIOK
                                                                                                             IMSTE
                                                                     »»STE»»TER

-------
                                                                   DRAFT
Styrene and butadiene (referred to as monomers) are either piped  to  the
plant from adjacent suppliers, or shipped in by tank car or tank  truck.
The monomers are stored in a tank farm which is diked to retain major
monomers spills and leakages and, in the case of fire, to control  the
spread of flaming liquid.  The fresh monomers are piped to the plant
from the tank farm and, if necessary,' passed through a caustic soda
scrubber before mixing with recycle monomers.  Some monomers, such as
butadiene, have inhibitors added to prevent premature polymerization
during shipment and storage.  These must be removed before the monomer
can be polymerized.  The  inhibitor is removed  in the caustic scrubber by
the circulation of a caustic soda solution, approximately 20 percent.
The caustic soda solution  is discarded periodically or can be subjected
to continual make-up and  blow.down.

Soap solution, catalyst,  activator, and  modifier are added to the monomer
mixture prior to entering the polymerization reactors,  the soap solu-
tion is used to produce an emulsion of the  monomers  in an aqueous medium.
The principal ingredients  of  this solution  are generally  a rosin acid
soap and a fatty acid soap.  Thy catalyst  is a free  radical  init-iator and
can be a hydroperoxide or a peroxysulfate.  The catalyst  initiates and
promotes the polymerization  reaction.  The  activator  assists  in generat-
ing the free radicals more rapidly and at  lower temperatures  than by
thermal decomposition of  the  catalyst alone.   The  modifier  is an^ad-^
ditive which adjusts  the  chain  length and  molecular weight distribution
of  the  rubber product during  polymerization.   It  is  necessary that  all
the above  solutions  be made with  high quality  water.   Usually city  or
well water is deionized  for  the preparation of the solutions.

The  polymerization  proceeds  stepwise through a train of reactors.   The
 reactor system  is  capable of  producing  either  "cold" (AO-*»5°F, 0-15 psig)
or  "hot"  (122°F,  AO-60  psig)  rubber.  The  "cold"  SBR polymers, produced
at  the lower  temperature and  stopped at  60 percent conversion, have im-
 proved  properties  when  compared to "hot" SBR's.   The "hot" process  is
 the older  of  the two.   For "cold" polymerization, the monomer-additive
 emulsion  is cooled prior to entering the reactors, generally by  using  an
 ammonia refrigerant cooling medium.   Depending on the polymerization tem-
 perature,  the medium could be chilled brine or chilled water.  In ad-
 dition,  each  reactor has  its own set of cooling coils, usually contain-
ing ammonia refrigerant, and is agitated by a mixer.  The residence t.me
 In each reactor is approximately one hour.  Any reactor  in the train can
 be by-passed.   The reactor system contributes significantly to the high
 degree of flexibility of  the overall plant in producing different grades
 of rubber.  The overall   polymerization  reaction is ordinarily carried to
 no greater than 60 percent conversion of monomer  to rubber since the rate
 of reaction falls off beyond this point and product quantity  beg.ns to
 deteriorate.   The product rubber is formed in the emulsion phase of the
 reaction mixture.  The reaction mixture is a milky white emuls.on called
 latex.
                                  111-23

-------
                                                                   DRAFT
Short  stop  solution  is added to the latex leaving the reactors  to stop
the polymerization at  the desired conversion.   Two common  short  stop
ingredient  are sodium  dimethyl  dithiocarbamate and hydroquinone.  The
"stopped" latex is held in blowdown tanks prior to the stripping operation.
The blowdown tanks act as flow regulating holding tanks.

Recovery of the unreacted monomers and their purification  is  an  essential
step in economic synthetic rubber production.   Butadiene,   which has a  lower
boiling point than styrene,  is first vacuum stripped from the latex.   The
stripping operation  is generally carried out in a vacuum flash tank at
about  80-90°F.  The butadiene vapors are compressed and condensed  before
entering a receiver.  A very small quantity of water collects in the
receiver and is discharged periodically.  The condensed butadiene  is  re-
cycled to the feed area and mixed with fresh monomer prior to the  polymer-
ization step.  Styrene recovery from the latex usually take's  place in
perforated plate stripping columns.  These operate with steam injection
at approximately 140 F.  The steam-styrene vapor mixture is condensed
and sent to a receiver where the styrene and water are decanted.  The
top styrene layer is recycled to the monomer feed stage; the bottom layer
of the receiver, which is  styrene-laden water, is discharged.  Both the
vacuum and steam strippers  foul periodically with rubber solids.  These
must be removed by hand,  followed with both steam or water jets.  This
cleaning operation puts the stripper out of commission and produces large
quantities of wastewater.

An antioxidant to protect  the  rubber from attack by  oxygen and ozone is
added to the stripped  latex in a  blend  tank.  The  latex is now  stabilized
and, as a  result, different batches,  recipes, or  dilutions can  be mixed.
These mixing operations  take place  in the blend  tanks.  The  latex  is
pumped  from  the blend  tank to  the  coagulation step where dilute (pH A-4.5)
sulfuric acid and sodium  chloride  solution  are added.  The acid brine
mixture  is  called the  coagulation  liquor and  causes  the rubber  to pre-
cipitate from  the latex.   Theoretically, precipitation will  occur with
a  coagulation  liquor  consisting  of any  combination of electrolyte  and
dilute  acid.  However,  the quality and  intended  end  use of the  rubber
 limit  the  choice  of coagulants.   For example,  some  types of  "hot"  SBR
which  are  used as  insulation  covering on electrical  wire are coagulated
with  an  acid-polyamine solution  in order to produce  a rubber with  low
electrical  conductivity.

As mentioned earlier,  rubber can be extended to  improve  its  properties
 by using oils  and carbon black.   Carbon black and oil can  be added to  the
 latex during the  coagulation step to produce a more intimate mixture than
 can be obtained  by  the subsequent addition of these materials^  the
 crumb rubber as  is  the case with conventional  rubber compounding.  Waste-
 waters generated  subsequent to the masterbatch operation  (addition of
 carbon black)  are usually black due to colloidal carbon black particles.
 The oil is added  as an aqueous emulsion, and carbon black is blended

-------
                                                                    DRAFT
into the latex as an aqueous slurry (approximately 5 percent  by weight).
There are various types of extending oils; some are staining  and  others
non-staining.  Non-stained rubber is required for some non-tire uses.
If a non-stained rubber is to be produced, not only must the  extender
oil be non-staining, but also lighter-colored soaps, short stops, and
antioxidants must be used.

The coagulated crumb is separated from the coagulation liquor on  a
shaker screen.  The coagulation liquor is recycled after make-up  with
fresh acid and brine and blowdown of part of the diluted liquor.   The
screened crumb is resuspended and washed with water in a reslurry tank.
This operation serves to remove extraneous compounds from the rubber,
particularly residual coagulation liquor.  The crumb rubber slurry is
then dewatered, generally using a vacuum filter, and the filtrate wash
water is recycled to the reslurry tank for reuse with fresh water make-
up and as an overflow.  The overflow is necessary to blowdown accummulat-
ing rubber solids and contaminants.  The coagulation liquor blowdown and
crumb slurry water overflows are usually passed through separators.
These facilities, called crumb pits, are generally outside the process-
ing building and trap the floatable crumb rubber.  The clarified  under-
flow is discharged.

The rinsed and filtered rubber crumb is finally dried with hot air in a
continuous belt or screen dryer.  After drying, the rubber is weighed
and pressed  in bales and stored prior to shipment.  Normally  rubber
bales weigh 75 pounds and are wrapped in polyethylene film.  The  balers
are operated hydraulically with oil or water as the hydraulic fluid.
Due to the jarring baling action and the high hydraulic pressures, fluid
leaks are frequent and, in the case of oil-driven balers, the leaked oil
should be prevented from entering the plant drain system.

In addition to the processing operations described above, other opera-
tions are carried out regularly, though not necessarily continuously,
which generate considerable quantities of wastewater.  These include
equipment cleanout and area washdown operations.  Principal equipment
cleanouts include the polymerization reactors, blowdown tanks, butadiene
flash tanks, styrene stripping columns, and latex blend tanks.   In most
cases, high volumes of wastewater are produced that are laden with un-
coagulated  latex solids and are characterized by a milky white appearance.
When the flash tanks and stripping columns are cleaned, the wastewaters
contain rubber solids, due to premature coagulation of the latex, in ad-
dition to uncoagulated  latex.  Area wash downs are frequent,  and the
wash waters pick up primarily latex, rubber solids, and oil.   The carbon
black slurrying area is generally contaminated with carbon powder.  Area
washdowns and storm  run off typically pick up the carbon, resulting in  a
fine carbon suspension.

It is opportune at  this point to review the potential wastewater sources
in a typical emulsion plant.  Table  I I I-5 summarizes  the principal waste-
waters and  the nature or appearance of their constituents.


                                 111-25

-------
                                                       Table  I I 1-5

                               Summary of  Potential  Process-Associated Wastewater  Sources  from
                                Crumb Rubber  Production via  Emulsion  Polymerization  Processing
        Processing Unit
                          Source
                                      Nature of Wastewater Contaminants
         Caustic  Soda Scrubber     Spent caustic  solution
ro
Monomer Recovery

Coagulation


Crumb Dewatering


Monomer Strippers



Tanks and Reactors


Al 1 Plant Areas
Decant water layer

Coagulation liquor overflow


Crumb rinse water overflow


Stripper cleanout rinse water



Cleanout rinse water


Area washdowns
High pH, alkalinity, and color.  Extremely
low average flow rate.

Dissolved and ^separable organics.

Acidity, dissolved organics, suspended and
high dissolved solids, and color.

Dissolved organics, and suspended and dissolved
sol ids.

Dissolved organics, and high suspended and
dissolved solids.   High quantities of uncoag-
ulated latex.

Dissolved organics, and suspended and dissolved
solids.  High  quantities of uncoagulated latex.

Dissolved and  separable organics, and suspen-
ded and dissolved  solids.

-------
                                                                   DRAFT
               Solution Crumb Production

As pointed out earlier, solution polymerization is a newer,  less  tradi-
tional, process for the commercial production of crumb rubber in  the U.S.
Solution polymerization systems permit the use of stereospecific  catalysts
of the Ziegler-Natta or alkyl-1ithium' types which have made  it possible
to polymerize monomers, such as isoprene or butadiene, in a  suitable
organic solvent so as to obtain the cis structure (up to 98  percent)
characteristic of the natural rubber molecule and with a high degree of
regularity.  Rubbers with the cis structure are desired since they are
usually rubbery, whereas the trans-configuration is more rigid and
similar to plastics.  Cis-polybutadiene, for example, has higher  abrasion
resistance than the usual SBR. type and  is being used mainly  to extend
and partially replace both SBR and natural rubber in tires.   Reports in-
dicate that tread wear  is improved by up to 35 percent rn a  50-50 blend
of polybutadiene and SBR.

A relative newcomer on  the rubber scene is based on the cheap monomers,
ethylene and propylene.  Although not stereo-regular, these polymers can
be produced in solution plants and can  use similar catalysts.  The polymer
chain, based on ethylene and propylene, does not contain sufficient un-
saturation for conventional curing.  The  incorporation of a third monomer,
usually a diene  (thus EPDM - ethylene propylene diene monomer), adds un-
saturation and facilitates conventional curing.

The production of synthetic  rubbers by  solution polymerization processes
is a stepwise operation, and,  in many aspects,  is very similar to pro-
duction by emulsion polymerization.  There are distinct differences  in
the two technologies however.  For solution polymerization, the monomers
must be extremely pure  and the solvent  (hexane,  for example)  should be
completely anhydrous.   In contrast to emulsion polymerization, where
the monomer conversion  is taken to approximately  60 percent,  solution
polymerization systems  are polymerized  to  conversion  levels which are
typically  in excess of  90 percent.  The polymerization reaction  is  also
more rapid, usually complete  in one to  two hours.

Figure  III-1*  is  a generalized  materials flow diagram  for the  production
of crumb SBR by  a solution polymerization  process.  The  processing  steps
shown  are essentially  typical  of  all  solution  polymerization  processes.
As  in  the case with emulsion  plants,  solution  plants  comprise several
processing  lines where  different  types  of rubber  for  distinct end uses
can be produced  (including non-extended,  oi1-extended, and  carbon black
master  batch varieties).  Plant operation  is  typically 24 hours  per day,
365 days per year.

The fresh monomers  are  pumped  to  the  plant from the tank farm.   Inhibited
monomers are  passed through  a  caustic soda scrubber to  remove the  in-
hibitor.   The  monomers  are  then  sent  to fractionator drying towers  where
extraneous  water is removed.   Fresh  and recycled solvent (for example,
                                 111-27

-------
                                   FIGURE  111-4
GENERAL WATER FLOW DIAGRAM FOR A SOLUTION POLYMERIZED
                    CRUMB RUBBER PRODUCTION  FACILITY
                                                                                                NOTE:




SOLVENT
STORAGE
UN
t
•ONDNER




CATALYST
VOUCHER









INHIBITED N

INHIBITED
MONOMER














ONOMER

MONOMER
INHIBITOR
REMOVAL
AND DASH

1









.







'I
•AU





TO MONOMER
RECOVERY

HtAYY ™" ••^— " 	
„ MONOMER ,_ SOLVE"T
5 SEPARATION ^- SF.PARATION
! t*\ n i
' fl~ IT'
i 1 ' 	 STEAM—* 1 1
HtSTE '
~ »ASTE»ATER
HEAVY
SLOPS

POLYMER-
• ^ FEED ^ !7IT.ny

ORTIIIG REACTOR ""
JC -
STIC
••^•ia^B^^


•i^t

TO MON
RECOVE
t
i L 1 GHT
^ MOHOM
\^ StfURA
n
STEAK JJ |
T
WASTF.N


CEMENT


•*






                                                                                                 EXTENDER Oil  AND CARBON
                                                                                                 SLACK ARE NOT ADDED TO
                                                                                                 NON-EXTENDED  RUBBER
                                                                                                 mts.
                                                                    COOLING
                                                                    IdTEfl
                                                                    SUPPLY
                                                          MAKEUP
                                                          DATED
                                                                OVERFLOK

                                                               KASTE«ATER
     EXTENDER  OIL
I	»>  IASTE»m«
DRYING
r^l


BALINC



PRODUCT
STORAGE
ANO
SHIPPING
                                                                            STEAM:
                                                                                                             WATER
  •ASHDOWN
                                                                                            REGENERATION
                                                                                            fUSTES  j

                                                                                                WASTE»ATER

-------
                                                                   DRAFT
hexane) is also passed through a drying column to remove water  and  ex-
traneous light and heavy components.  The light- and heavy-components
build up in the system as unwanted by-products or unrecovered monomer
during the polymerization step and must be removed.  The purified  sol-
vent and monomers are then blended.  The mixture is generally termed the
"mixed feed".  The mixed fixed can be further dried to remove final traces
of water using a desiccant column.

The dried mixed feed  is now ready for the polymerization step and  catalysts
can be added to the solution  (solvent plus monomers).  The catalyst sys-
tems used vary.  Typically they are titanium halide plus aluminum  alkyl
combinations or butyl lithium  compounds.  The catalysts can be added to
the mixed feed just prior to  .the polymerization  stage or to the lead
polymerization reactor.

The blend of solution and catalysts is polymerized  in a series  of  re-
actors.  The reaction is highly exothermic and heat  is  removed  continu-
ously  by either an ammonia refrigerant or by chilled brine or glycol
solutions.  The reactors are  similar  in both design and operation  to
those  used  in emulsion polymerization.  The mixture  leaves the reactor
train  as a  rubber cement,  i.e., polymeric rubber solids dissolved  in
solvent.

A short stop solution is added  to  the cement after  the  desired conversion
is  reached.  The stabilized cement  is pumped to  cement  storage tanks
prior  to subsequent processing.  At this point other  ingredients,  such as
antioxidants, can be  added.   If the rubber  is to be oil extended,  oil
can be added to the cement.   The oil  is  usually  blended with the cement
at  some point between the  storage  tanks  and  the  steam stripping operation.

The rubber  cement  is  pumped  from  the  storage  tank  to the  coagulator
where  the  rubber  is precipitated  into crumb  form with hot water under
violent agitation.  Wetting  agents (surfactants) can be added  to promote
the control  of crumb  size  and to  prevent  reagglomeration.   In  addition
to  coagulation, much  of  the  solvent and  unreacted  monomer are  stripped
overhead.   For carbon black  masterbatch  rubbers, the carbon black  slurry
 is  added  to the coagulator in much the same manner as for emulsion crumb
 rubber.

The resultant  crumb  slurry passes  to  a  series  of strippers  where steam
 stripping  drives  off  the remaining monomers and solvent.  The  strippers
are generally  a  flash tank or agitated  kettle strippers.  The  steam,
 solvent,  and monomer  vapors  are condensed and sent to a decant system.
The bottom decant  layer,  saturated in monomers  and solvent,  is discharged.
 The organic layer is  sent to a multi-stage  fractionator (described earlier)
 Light fractions  are removed  in the first column and generally  consist of
 unreacted  light  monomer (for example, butadiene).   This is  normally re-
 claimed at the monomer supply plant.   The second column produces  purified
 solvent,  a heavy monomer-water fraction, and extraneous heavy  components.
                                 111-29

-------
                                                                   DRAFT
The heavy monomer (for example, styrene) is condensed,  decanted,  and  re-
cycled.  The bottom water layer is discharged.  The purified solvent  is
dried and reused.  The heavy monomer is a waste stream which can  either
be decanted before disposal  or can be incinerated as a  slop oil.

The stripped crumb slurry is separated and further washed with water  on
vibrating screens.  The slurry rinse water is recycled  in part to the
coagulation stage with water or steam makeup.  The remaining portion  of
the slurry rinse water overflows and is discharged.  This water contains
floating crumb rubber fines and is generally passed through a crumb pit
before discharge.  The crumb fines are trapped in the pit.  The screened
rubber is passed through an extruder-dryer for further dewatering and
drying.  Dewatering and drying can also be carried out with a rotary
filter and hot air oven dryer.  The dried rubber is pressed into 75-pound
bales and is usually wrapped in polyethylene for shipment.' Balers, identi-
cal to those employed in emulsion processing, are used in solution-
polymerized rubber production.  Oil leaks are a potential problem.

In addition to the processing operations described above, area wash-
downs occur.  These are frequent and produce large volumes of wastewater
which can be contaminated with dissolved organics, floating organics,
oils, and suspended solids.  Since the majority of the processing steps
are operated on a strict water-free basis, there is little need for
equipment cleanout operations with water.  The processing units which
are kept free of water are cleaned out with solvent when necessary.  This
cleaning solvent  is stored separately and  is used solely for the cleanout
operation.  Process pumps, handling in particular the dried mixed feed
prior to and during the polymerization stage, use a non-aqueous fluid
(usually an oil) as a seal in  lieu of water  to prevent contamination of
the process streams with water.  Leaking fluid  is a potential source of
oil which can be picked up by area washdown waters.  The carbon black
slurrying area is a source of wastewaters  laden with carbon fines.

The main wastewater sources  in a typical solution polymerization  plant
are summarized in Table  I I 1-6.

               Latex Production

In addition to solid crumb rubber, emulsion  polymerization  is also used
to produce  latex  rubber.  Latex production follows  the same processing
steps as emulsion crumb production with  the  exception of  latex coagulation
and crumb  rinsing, drying, and baling.   Only  about  5 to  10  percent of
SBR  is used as latex, but approximately  30 percent  of  the  nitrile  rubbers
 (NBR) enter the  market as  latex.   Commercially ,avallable  SBR  latexes con-
tain about  45- to 55-percent  solids,  although  some  can be  as  high  as
68 percent.  Most NBR  latexes  are  in  the k$- to 55-percent  solids  class.
The polymerizations are  taken  essentially  to completion  (about 98 to
99 percent  conversion) as opposed  to  emulsion  crumb rubber production
where conversion  per  polymerization pass is  approximately  60  percent.
                                 111-30

-------
                                               Table I I 1-6

                       Summary  of  Potential  Process-Associated Wastewater  Sources  from
                        Crumb Rubber  Production  via  Solution  Polymerization  Processing
Processing Unit
Source
Nature of Wastewater Contaminants
Caustic Soda Scrubber     Spent caustic solution
Solvent Purification

Monomer Recovery

Crumb Dewatering
Fractionator bottoms

Decant water layer

Crumb rinse water overflow
High pH, alkalinity, and color.  Extremely
low average flow rate

Dissolved and separable organics.

Dissolved and separable organics.

Dissolved organics, and suspended and dissolved
sol ids.
All Plant Areas
Area washdowns
Dissolved and separable organics, and suspended
and dissolved solids.

-------
                                                                   DRAFT
As a result, the recovery of unused monomer is not economical.   Process
economics are directed towards maximum conversion on a once-through
basis.

Figure  I I I-5 is a generalized materials flow diagram for the production
of latex SBR by emulsion polymerization.  The steps shown are typical  of
all latex production processes.  Although latex plants are generally
operated 2*4 hours per day and 3&5 days per year, the production  runs  for
each recipe or type of latex are shorter than in emulsion or solution
crumb rubber plants because latex consumption is on a smaller scale and
latex consumers are usually outside companies with varying product needs.
By contrast, the majority of crumb rubber is made for tire manufacture,
is consumed by major tire companies, and is produced by their own syn-
thetic rubber producing divisions.  This has the effect of limiting  the
number of types of product and  recipe, rationalizing production  schedules,
and, in the finaJ analysis, leading to long production runs.  Latexes^are
used to manufacture dipped goods, paper coatings, paints, carpet backing,
and many other commodities.

The monomers are piped from the  tank farm to  the processing plant.
Monomer  inhibitors are scrubbed  out by using  caustic soda solution.
Soap solution, catalysts, and modifiers are added to the monomer to pro-
duce a feed emulsion prior to  feeding  to the  reactors.  The water used
in  the preparation of the above  solutions  is  generally deionized city
or well water.  The number of  reactors  in the  reactor  train  is usually
smaller  than that used for emulsion crumb production.  The  temperature
is  generally kept at approximately kO  to **5°F and,  therefore, most
latexes  are made by the  "cold"  process.  When  the polymerization is com-
plete, the  latex is sent  to a  blowdown  tank  for intermediate storage or
holding.  Stabilizers are usually  added  to  the  latex at  this point to
stop the polymerization  and  to stabilize  the  latex.

The latex passes from the blowdown  tanks  to  a vacuum  stripper where the
unreacted butadiene  is  removed.  The  butadiene is  vented  to the  atmos-
phere.   The vacuum  is pulled  with  either a  vacuum pump or steam  jet.
The excess  styrene  is stripped from the latex in a  steam stripper.  The
steam  and  styrene are condensed and  sent to a receiver.   The bottom
water  layer is  decanted  off and discharged.   The styrene layer  is not
recycled and requires disposal.

The stripped latex  is passed through a series of screen filters  to re-
move unwanted  large rubber  solids.  The latex is finally stored  in blend-
 ing tanks  where various  additives  (for example, antioxidants) are mixed
with the latex.  The  latex is shipped from the blending tanks by tank .
car or tank truck,  or is drummed ready for dispatch.

 Since  short production  runs are common to the industry, the major waste-
waters generated in a synthetic latex plant stem from equipment cleanout
 operations.  When  production is switched from one type of rubber to  an-
other, reactors, blowdown tanks, strippers, and filters requ.re clean,ng
                                  111-32

-------
                                             FIGURE  111-5

GENERAL WATER FLOW  DIAGRAM FOR AN EMULSION  LATEX RUBBER  PRODUCTION  FACILITY
DAI INTAKE WATER _


COOLING
TOIER
TREATMENT



COOL
TO«E

KG
R
	 II 	
                           COOLING
                           WATER
                           RETURN
                           COOLING
                           WATER
                           SUPPLT
LIGHT MONOMER
TO ATMOSPHERE
                                                STEAM
                                                                       COJtDENCATE
                                                                       RETURN
                                      TREATED
                                      PROCESS
                                      HATER
SUPPLY
4-""'.. «-.

BOILER
HOUSE
1
, *





WATER
TREATMENT
UNITS
IA« INTAKE
IATER
                                                       SLOWDOWN
                                                          I
                                                       WASTEWATEB
                                                                                              •ASTEWATEd

-------
                                                                   DRAFT
for the new product.   In addition, tank cars and tank trucks  owned or
leased by the plant require cleaning after each trip.  Area washdowns
are frequent inside the processing buildings and at the vehicle  loading-
unloading areas.   All  the above wastewaters will contain oils,  dissolved
organics, and high concentrations of latex solids.

Table III-? summarizes the origins and nature of the principal  waste-
water sources generated in a typical synthetic  latex plant.

Summa ry

The growth of the tire and inner  tube  industry  has been closely linked
to the growth of the automobile  industry.  Current production is over
210 million tires per year with one quarter of  this  production destined
for original equipment on new vehicles.  The production of both tires  and
inner tubes consist of the compounding, extruding, calendering, and mold-
ing of solid raw materials.  There  is  considerable heat generated by
these processes and it must be dissipated  and controlled to  insure the
quality of  the final product.  Water used  in the  process, other than for
utilities,  consists of makeup water for soapstone  solution and latex dip
solutions.

The production capacity and output  of  the  synthetic  rubber industry are
expanding steadily and are  linked very closely  to  consumption by the tire
industry.   The relative production  levels  for  the various types of syn-
thetic  rubber will not  change  significantly  over  the next several years
to affect the operations  or wastewater impact  of  the industry as a whole.
Two distinct processing technologies  (emulsion  and solution) exist.  Pro-
cess  variations within  each of  these  two  technologies are only minor.
Two different types of  rubber  product  are  manufactured:  crumb and  latex
rubbers.  The so-called  specialty rubbers  are  manufactured by  processes
similar  to  those  used  to  produce the  so-called tire rubbers  and are in
similar  product  forms,  i.e.,  solid  and latex rubbers.

-------
                                               Table I I 1-7

                      Summary of Potential  Process-Associated Wastewater Sources from
                          Latex Production via Emulsion  Polymerization Processing
Processing Unit
Source
Nature of Wastewater Contaminants
Caustic Soda Scrubber
Excess Monomer Stripping

Tanks, Reactors, and Strip-
pers
Tank Cars and Tank Trucks
Al1 Plant Areas
Spent caustic solution


Decant water layer

Cleanout rinse water



Cleanout rinse water



Area washdowns
High pH, alkalinity, and color.  Extremely
low average flow rate.

Dissolved and separable organics.

Dissolved organics, suspended and dissolved
solids.  High quantities of uncoagulated
latex.

Dissolved organics, suspended and dissolved
solids.  High quantities of uncoagulated
latex.

Dissolved and separable organics, and sus-
pended and dissolved solids.

-------
                                                                     DRAFT
                                SECTION IV

                         INDUSTRY CATEGORIZATION
Introduction
Industry categories and subcategories were established  so  as  to define
those sectors of the rubber industry where separate effluent  limitations
and standards should apply.  In the final  analysis, the underlying dis-
tinctions between the various categories and subcategories have been
based on the wastewater generated, its quantity, characteristics, and
applicability of control and treatment.  The factors considered  in deter-
mining whether such categorizations are justified were the following:

     1.  Manufacturing Process.
     2.  Product.
     3.  Raw Materials.
     k.  Plant Size.
     5.  Plant Age.
     6.  Plant Location.
     7.  Air Pollution Control Equipment.
     8.  Nature  of Wastes  Generated.
     9.  Treatability of Wastewaters.

As  indicated  in  Section  III,  there  are inherent  differences  between the
tire and  inner  tube  sector,  and  the  synthetic  rubber sector  of the rubber
industry;  therefore,  the  two have been separated to produce  the two prin-
cipal  industry  categorizations.

Tire and  Inner  Tube  Industry

     Manufacturing Process

The process steps by which tires are made are similar  throughout the
 industry   Although  there are variations  due to equipment manufacturer
and automation,  these differences do not  lead to significant variations
 in the volume or constituents of process  waters.

      Product

 Examination of existing plants  indicates that the end product is not  a
 reasonable basis for categorization.  Manufacturing steps ?£ all  t  re
 production are similar; inner tube manufacture, although d.fferent  in
 some respects, generates  the same type of'process wastewater streams  as
 does tnTtire'production.  The  characteristics^  the waste stream and
 the potential treatment technologies  are not  significantly d.fferent.

 Radial tire manufacture  is  different  in  the building, molding, and
 curing operations; however, these differences do  not  sign.f.cantly
                                  IV-1

-------
                                                                   DRAFT
impact on wastewater quantity or quality.  In addition, radial  tires  are
generally produced in the same plants as bias tires.

     Raw Materials

Since the basic raw materials for the entire industry are rubber,  carbon
black and oil, categorization based on raw material usage is not rea-
sonable.  The quantities and form of the different raw materials re-
ceived varies, but these do not significantly affect the control or
treatment technologies applicable to the industry.  The handling of raw
materials, particularly the carbon black, also varies within the indus-
try.  However, this again does not affect the process wastewaters  or
the!r treatabi1ity.

     Plant Size

A listing of most plants currently operating and their production rates
is given  in Table IV-1 .  The distribution of these  is presented in
Figure  IV-1.  From inspection of existing and plant visit data, it was
learned that plant size has no significant effect on the quality or
treatabi1ity of wastewaters.  Process effluent quantities varied signi-
ficantly  but was not directly related to plant size.  The only signifi-
cance of  size is the cost of treatment of wastewater streams, which,  of
course, is related to other factors.

     Plant Age

The age of plants currently  in operation will fall  into  three basic
categories depending on the expansion period  in which  the plant was
built.  The oldest plant  in operation is an  inner  tube facility built
in  I
As constructed, production  facilities  built  during  the  first two expan-
sion periods tend  to  be  multi-storied,  with  process  lines  located on
many floors and confined to small  areas.   In addition,  plants from^the
first expansion period most probably have  undergone  modifications in
order to update their machine  processing technology  (for example, the
installation of internal  mixers).   Most likely  this  would  further con-
gest the processing area.   Much  of the equipment  in  these  older plants
is old and of designs that  have  since  been updated  to  reduce mainte-
nance and operational costs.   Process,  non-process,  and domestic waste-
water sewers exist as a  combined sewer, thus making  process contaminants
difficult to locate or  treat once  they reach the  drainage  system.  Engi-
neering diagrams of sewers  within  the  plant  are dated  and  possibly non-
existent.  Drains  that  do exist  were  located for  ease  of washdown of
contaminants, thus making their  position inappropriate by  current think-
 ing  and  standards.

The newer plants of the  last expansion  period have the  benefit of modern
                                 IV-2

-------
                                                Table IV-1
                           Major Tire Production Facilities in the United States
  Company

  Armstrong




  Carlisle

  Cooper


  Corduroy

  Denman

  Dunlop

  Fi res tone
Location
  Gates


  General
DesMoines, la.
Hanford, Cal.
Natchez, Miss.
W. Haven, Conn.

Carlisle, Pa.

Findlay, Ohio
Texarkana, Tex.

Grand Rapids, Mich.

Warren, Ohio

Buffalo, N.Y.

Akron, Ohio
Albany, Ga.
Barberton, Ohio
Bloomington, 111.
Dayton, Ohio
Oecatur, 111.
DesMoines, la.
Los Angeles, Cal.
Memphis, Tenn.
Pottstown, Pa.
Salinas, Cal.

Denver, Colo.
Nashvilie, Tenn.

Akron, Ohio
Bryan, Ohio
Charlotte, N.C.
Mayfield, Ky.
Waco, Tex.
Unjts/day

 20,000
 10,500
 14,600
 13,500
 13,000
 11,500
 27,000
 17,000
  8,500
     50
 20,700
 22,000
 22,000
 15,500
 28,000
 30,000
 15,500

 18,200
 10,000

  9,050
     30
 12,000
 23,000
 16,000
Company

Goodrich
                    Goodyear
Mansfield


McCreary

Mohawk



Schenuit

Uni royal
 Locat ion

 Akron, Ohio
 Ft. Wayne,  Ind.
 Los Angeles, Cal.
 Oaks, Pa.
 Tuscaloosa, Ala.

 Akron, Ohio
 Conshohocken, Pa.
 Cumberland, Md.
 Danvilie, Va.
 Freeport, 111.
 Gadsden, Ala.
 Jackson, Mich.
 Los Angeles, Cal.
 Topeka, Kans.
 Tyler, Tex.
 Union City, Tenn.

 Mansfield, Ohio
 Tupelo, Miss.

 Indiana, Pa.

 Akron, Ohio
 Salem, W.  Va.
W. Helena, Ark.
Baltimore, Md.

Chicopee FalIs,
Detroit, Mich.
Eau C lai re, Wis.
Los Angeles,  Cal
Opeli ka, Ala.
Mass.
       Units/day

        6,000
        18,000
        11,500
        19,000
        21,000

        38,000
        13,000
        20,500
        4,100
        14,000
        44,000
        30,000
       30,000
       15,000
       30,000

       14,000
       12,500

        3,500

        6,000
        4,700
       10,000
29,000
39,745
30,000
16,500
13,500
Source:   "Rubber Reuse  and  Solid  Waste Management," U.S. Environmental  Protection Agency,  1971.

-------
                                       FIGURE IV-1
  LOCATION OF TIRE  MANUFACTURING  PLANTS, PRODUCTION GREATER THAN  20,000
  UNITS/DAY, AND  SYNTHETIC RUBBER PRODUCTION PLANTS, PRODUCTION GREATER
  THAN  60,000  LONG TONS/YEAR, WITHIN THE U. S. 1972.
                                                •   A A  .- ILL.  | 1ND> \ onIQ.O. A
                                                             •       /..), .!«* • •
                Xr'WK."K	   '           '
                 \l        / WMrv    T	
                                        "^*i n^* •     1^" *^" *" * ^ *^T ^™ A        */    n« ^ •
                                     •     I UAlft.    *«DK    ^"TEMH   /"   •—«

                                          •               .-.. i P o • A i &  *. OR.  \_ S. U.  i
LEGEND
 A TIRE MANUFACTURING PLANTS
 • SYNTHETIC RUBBER PLANTS
                                                                                            'i

-------
                                                                    DRAFT
design criteria and updated thinking  in both the sanitary and mainte-
nance engineering fields.  Buildings  are single-story and contain more
area per process line.  Equipment and area locations have been designed
for a cleaner, more maintenance-free  operation.  Sewers are no longer
combined, thus making process sewer wastewaters easier to locate and
treat.  Drains are not  located  in areas where contaminants can gain easy
entrance.

By the above reasoning, the process wastewater streams from older plants
should be larger in volume and  should contain higher loadings of both
oily and solid materials..  Control and treatment should be more diffi-
cult.  Examination of plant wastewater streams from all these areas
bears this out.

The years between 1950  and I960 are the transition period between the
second and third expansion period.  Plants constructed in the early
1950's were built during  the Korean War and will most  likely have the
same problems as those  built in the World War  II era.  Few (if any)
plants were built after the Korean War until 1959, when the current
expansion began.  The year 1959, therefore, is the demarcation point
between old and new facilities.

     Plant Location

From inspection and wastewater  sampling of plants located in three
geographical areas of the country and from analysis of existing data,
plant location will have  no effect on the quality or quantity of the
process wastewater streams.  These geographical areas  included the
South, the Far West, and  the Northern Midwest.  Geographical location
has a significant effect  on the supply of water; therefore, management
of non-process streams  such as  cooling water and steam varied from region
to region.  Recirculation of cooling  water  is  very common in the Far
West (where water supplies are  short), whereas  it is  less common  in other
sections of the country.  Reduction of non-process wastewaters by re-
cycle increases the treatability of process wastewaters when combined
with non-process wastewaters in an end-of-pipe treatment facility.
Treatability of process wastewater streams, however,  is more effectively
carried out before combination  with non-process streams.  In addition,
geography does not limit  the use of recirculated water to the Far West.
Plants in other parts of  the country  are also  using recycle, though not
necessarily for the same  reasons.

Plants visited also represented both  rural and urban areas.  Plants lo-
cated in urban areas tended to  occupy and own  less  land, thus increasing
treatment cost where available  open land  is a  consideration.  However,
both the location and the characteristics and  quantity of the water to
be treated are better  related to the  age of the plant.  Urban plants are
older facilities, whereas rural plants tend to be newer.  Therefore,
                                 IV-5

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                                                                   DRAFT
location is not a reasonable basis for categorization.

     Air Pollution Control Equipment

The type of air pollution equipment employed by a facility can have  a
great effect on the characteristics and treatability of the process
wastewater streams.  The use of dry equipment or the recycling of  dis-
charges from wet equipment was observed in all areas of the plant  which
are currently served by such devices.  Therefore, since company policy
(rather than the situation to be controlled) dictates the type of  equip-
ment used, air pollution equipment does not form a suitable basis  for
categorization.

     Nature of Wastes Generated

From evaluation of all available data, the type of wastes generated  by
all facilities in the tire and inner tube  industry are similar. The
addition or subtraction of the latex dipping of fabric from the process
line can affect the characteristics of the process wastewaters.  However,
as supported by existing data, this discharge  is not large and can be
easily contained.  Therefore, it does not  necessarily affect the treat-
ability of process wastewaters and does not form a basis for categoriza-
tion.

     Treatability of Wastewaters

The treatment technologies employed by companies throughout the industry
are similar.  Wastewater constituents are  also very  similar: mainly oil
and solids.  Treatability  is more a factor of  age than of the specific
pollutant and, therefore, does not form a  basis for  categorization.

     Summary

Only the age of the production facility forms  a rational basis for
categorization.  As indicated, tire manufacturing facilities built in
earlier periods, although using similar manufacturing techniques,  have
greater wastewater problems than do new plants built in  recent times.
On this basis, there should be two separate categories:  old plants,  and
newer plants.  Plants built prior to  1959  are  considered old; those
built during and after  1959 are considered new.   Inner tube facilities,
although producing a different product, incur  the same difficulties as
do the older plants and  should be  included in  the "old"  category.

Camelback operation, a  small segment of the  industry, should also be
included  in the "old" or "new" categorization  of  tire plants depending
on the tire facility of  which  it  is a part.   If  located  by  itself, the
camelback should meet standards according  to  the  date of  its^construc-
tion.  Compounding operations, another small  segment of  the industry,
should fall into the category of  the  plants with  which they coexist.  If
                                 IV-6

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                                                                   DRAFT
located by itself in a separate location, the compounding  facility
should meet standards of "old" or "new" tire plants depending on  its
original date of operation.

As a consequence, only two categories are indicated for SIC  code  3011,
namely "old" and "new" tire facilities.  The demarcation date between
the categories is the year 1959.

Synthetic Rubber Industry

     Manufacturing Process

As described in Section  I I I of this document, there are two basic pro-
cessing techniques  in common use  in the  industry to produce synthetic
rubber:  emulsion polymerization  processing and solution polymerization
processing.

Emulsion polymerization  as a commercial  process dates back to World War
II.  No significant changes have  been  made  in the  basic process since
the first emulsion  polymerization plants were built.  Emulsion polymeri-
zation processing  is  used, however, to make both emulsion crumb and latex
rubber.  From both  operccional  and wastewater points of view, crumb and
latex production techniques should be  considered separately.

Solution polymerization  production facilities are  different from emul-
sion plants  from both process  and wastewater points of  view and have
been considered  as  a  separate  sub-category.  Differences  among solution
rubber  production  plants are minor.  All  solution  plants  consist of
feed preparation,  polymerization, solvent  and monomer  recovery, coagu-
lation, and  rubber  finishing  operations.   The operations  that have the
greatest wastewater impact in  solution plants are  those operations which
are most  similar plant to plant.

 It was  therefore concluded that there  are essentially  three manufacturing
process variations  which merit separate subcategories:  emulsion poly-
merization  to crumb rubber;  solution  polymerization to crumb rubber; and
emulsion  polymerization to latex.

      Product

There  are two principal  product sub-categories  in  the  synthetic  rubber
 industry,  crumb and latex product.

Within the crumb sub-category there are several product variations  which
 involved  the type  of rubber (styrene-butadiene, or polybutad.ene,  etc.)
 and whether the rubber  is extended or not.  The two principal  products
 made by emulsion polymerization  are SBR and nitrile rubber. The process
 ooerations for  the two  rubbers are identical, and the  same or  similar
 equipment is used?  Several types of  rubber are produced by solut.on  poly-
 mer zat?on processes;   in many cases  similar solvents  and monomers are used,
 equivalent processing operations are  carried out, and   Identical  process,ng


                                  lv-7

-------
                                                                  DRAFT
equipment is used.

The processing variations involved in the manufacture of either  oil-
extended or carbon-black-extended rubber are minor.  In addition,  the
oil and carbon black are very effectively tied up with the rubber,  thus
reducing the potential for wastewater impact.

The effects that  the various  types of latex  rubber (for example, SBR  and
NBR) have on the  production operations and wastewaters are minor.   The
same equipment and processes  are  used for all types.

As pointed out in Section III, the specialty rubbers are essentially
similar to the tire rubbers from a processing point of view, and no
separate categorization is deemed necessary.

It has been concluded that only two principal product subcategories are
required to adequately define the synthetic  rubber industry.  They are
crumb and latex rubber.

     Raw Materials

The monomeric raw materials used  to produce  the various types of syn-
thetic have similar properties.  They are usually unsaturated hydrocar-
bons with extremely low solubility in water.  Chloroprene, a chlorinated
hydrocarbon used  to make neoprene rubber, is also  insoluble in water.  In
addition to low solubility, most  of the monomers used have high volatil-
ity  and, consequently, a monomer floating on wastewater soon evaporates.
Most solvents used also have  low  solubility  and high volatility and do
not remain  in a wastewater.   The  catalysts,  modifiers,  antioxidants,
etc. used in polymerizations  are  generally similar and  are used in such
low concentrations that their effect on wastewater  is minimal.  Their
presence  is generally undetectable in the wastewaters.

In conclusion, there  is no need for a subcategorization based on the
raw materials used.

     Plant  Size

Most emulsion and solution crumb  rubber plants consist  of  several  par-
allel  and  integral processing  lines.   Each  of these  lines  tends to be
of similar  size.   The wastewaters generated  by a plant, therefore, are
normally  directly proportional  to the production capacity.

Small  production  facilities  (for  example,  latex  plants), will bear a
somewhat  higher  treatment  cost  than  larger  plants.   However,  these plants
are generally part of  a  larger  synthetic  rubber  or organic chemical
complex,  and  the treatment cost can  be  shared.   In any  case,  latex
plants are  considered  as  a  separate  sub-category.

For these reasons, sub-categorization  according  to plant  size is not
necessary.

                                 IV-8

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                                                                  DRAFT
     Plant Age

Many emulsion plants (crumb and latex rubber) were built during  or
shortly after World War  II.  Few have been built since.   In addition,
technology has not changed appreciably since that time.

Solution plants are generally newer, but all have been built in  the
last 13 years.  The technology has not changed radically during  that
time period.

It has been concluded that plant age is not  a significant factor for
separate subcategorization.

     Plant  Location

Most of the  larger  synthetic  rubber plants  are  located  in one geogra-
phic region.  (Refer to  Figure  IV-1.)  This  fact  is closely connected
to the availability of  the monomeric raw materials.  The location of
the plants  does not  influence  the  processing operation.  However, geo-
graphic location  can  influence  the performance  of aerated  lagoons and
stabilization ponds.  Comparable secondary  wastewater treatment alter-
natives, such as  activated sludge, do exist, but  the performance is not
dependent on  geographic location.   It  is not necessary  to  subcategorize
the synthetic rubber  industry  by plant  location.

     Air Pollution  Control Equipment

Generally,  air  pollution control devices are not required  by the indus-
try.   Odor  problems do  exist  at some  plants, but these  are controlled
by  devices  which  are  either  dry or which  do not impact  on  the waste-
waters of the plant.

Air pollution control  is not  a subject  for subcategorization of the
synthetic  rubber  industry.

     Nature of  Wastes Generated

The differences in the characteristics of wastewaters  generated by
production  of non-extended,  oil-extended,  and carbon-black-extended
emulsion  crumb  rubber were not discernible.  Similarly, the wastewater
characteristics produced by  non-extended,  oi1-extended, and carbon-
black-extended  solution crumb plants were essentially  identical;  however,
wastewaters from emulsion crumb, solution crumb, and latex rubber  produc-
 tion  facilities were significantly different to warrant subcategor.zat.on.

 These facts indicate that separate subcategories are required  only for
 emulsion crumb, solution crumb, and latex  rubber product.on.
                                  IV-9

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                                                                   DRAFT
     Treatability of Wastewaters

Since the wastewaters generated by emulsion crumb and latex production
require chemical  coagulation prior to primary clarification whereas  the
wastewaters produced by solution crumb plants do not, there is a  dif-
ference in the treatability of synthetic rubber wastes.  In addition, the
COD and BOD loading from latex plants is considerably higher than from
emulsion and solution crumb plants, and requires more extensive treat-
ment.

It was concluded that, based on the treatability of the wastewaters,
three subcategories were required:  emulsion crumb, solution crumb,
and  latex rubber production.

     Summary

For  the purpose of establishing effluent limitations guidelines and
standards, the synthetic rubber industry should  be separated  into three
subcategories which are based on  distinct  processing and product dif-
ferences.  These subcategories  are:

     1.  Emulsion crumb rubber.
     2.  Solution crumb rubber.
     3.  Latex rubber.
                                 IV-10

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                                                                   DRAFT
                                SECTION V

                         WASTE CHARACTERIZATION
Tire and Inner Tube Industry

A general process flow diagram for a typical tire production  facility  is
presented in Figure I I I-1 .  Figure I I I-2 presents a typical  inner  tube
production process diagram.

The primary water usage  in a tire and inner tube facility is  for non-
contact cooling and heating. . Discharges from service utilities  supplying
cooling water and steam are the major source of contaminants  in  the final
effluent.  Characteristics of these wastewaters are COD, BOD, suspended
solids, and dissolved solids.

Table V-l presents the raw waste  loading for the combined process  and
non-process wastewaters of the plants visited.  Flow variations  are due
mainly to the use of once-through cooling water in certain plants  as
opposed to recirculating cooling water.  Plants A and B are new plants
using totally recirculated cooling water.   Plants E and G are old facili-
ties also using recirculated water.  A  comparison of these four plants
indicates that no significant variations in flow exist due to age of
the plant.

Plant F  typifies a plant using once-through water as its primary source
of process cooling.  COD and BOD  loadings  vary  to a great degree by the
type and amount of chemicals used  in the treatment of boiler and cooling
tower makeup waters.  Larger loadings  for  older plants  indicate an  in-
creased  amount of process  wastewater pollutants in the  effluent.   Load-
ings measured  in Plant A are high  due  to the practice of discharging
washdowns of soapstone and latex  dip areas  noticed during the sampling
period.  This  plant uses holding  lagoons.   Because all  wastes are  con-
tained within  the plant's  boundaries,  Plant A  discharges contaminants
which other exemplary  plants  (using different  technologies)  can not ac-
complish.  These contaminants  lead to  a correspondingly higher  loading.

Suspended  solid  loadings evolve  primarily  due  to water  treatment  blowdowns,
wastes   and boiler  blowdowns.   In addition, the suspended solid loadings
 in  process wastewater  can  increase due to  spills,  leakage, and  soapstone
discharge.  Loadings  for old  plants  tend to be higher  than those  for new
plants.  This  is  due  in  part  to  the use of older water  treatment  tech-
niques  and  the larger  volumes  of process wastewater  containing  solids
discharged  by  older facilities.

The quantity  of dissolved solids discharged is related  to  the amount  of
 recirculated  non-process water and the water supply  source.   Plants using
well  water typically have higher dissolved solid loadings,  than those
 using municipal  or river water sources.

                                    V-1

-------
                                                        TABLE  V  -  1



                        Raw Waste  Loads  of Untreated Effluent  From Tire and Inner Tube  Facilities



                     FLOW             COO               BOD                 S£               TDS                OIL

         Gate-   liters/1,000 kg  liters/1,000 kg   liters/1,000 kg   liters/1,000 kg   liters/1,000 kg   liters/1,000 kg

 Plant   gory    of raw material  of raw material   of raw material    of raw material   of raw material   of raw material





   A      .'Jew        6344.0           1.890            0.067              0.960              4.800             0.243



   B      New        3430.0            .184            0.002              0.047              0.159             0.075



   C1     .Jew        8251.0             -                -               1.155                -              0.794



   D      New       10883.0           0.142            0.012              0.092              0.879             0.009


   E      Old        5453.0           0.100            0.001              0.440              0.001             0.0272



   f      Old      123480.0           3.398            0.296              1.358              0.001             0.650
«<•


*  G      Old        3220.0           0.645            0.093              3.429              0.000             0.267



   H      Old       72427.0           0.001            0.036              0.676              0.000             0.167


    1      Old       10610.0           0.615            0.148              2.812              1.810             0.172
     Estimated, raw material consumption not known.

     2
     Includes treatment by in-plant sumps.

-------
                                                                   DRAFT
Table V-1 also shows  that the plant's final end product has  no significant
effect upon the  raw waste loading  in the final effluent.   Data from
Plant H, which produces primarily  truck and industrial tires,  is  not
substantially very different from  Plants E, F, or G, which,  while pro-
ducing a combination  of products,  produce mainly passenger tires.  Load-
ings from Plant  I are similar to the others, even though  this  plant's
primary product  is the manufacture of inner tubes.

To substantiate  the data and conclusions on total final effluent, Corps
of Engineers water discharge permit applications were obtained for a
large segment of the  tire and inner tube industry.  Comparison of Corp.
permits for plants considered old  and new revealed that the  above find-
ings and conclusions  are substantially correct.  Table V-2 lists  the
main characteristics  and the loadings corresponding to a  typical  old
and typical new  tire  production facility.

Raw waste loads  in the process wastewaters leaving the production facili-
ty are presented in Table V-3.  Flows rates are estimates only, mainly
due to the intermittent nature of  the waste discharges.  Although there
appears to be no significant difference in the measured flow rates as
shown by data, the composition of  the flows originating from old  and  new
plants differs greatly.  New Plant A uses large amounts of washdown water
which comprises  the bulk of their  process wastewaters.  New  Plant B pro-
cess wastewaters consist largely of discharges from an extensive  wet  air
pollution train.  The discharges from this equipment are the primary  con-
stituent of the  process wastewaters.  The process wastewater flow rates
leaving older plants  are due to other factors such as spills,  leakage,
runoff from storage areas and inherent plant practices of older facili-
ties.  Therefore the  data indicate that, given the same housekeeping  poli-
cies and the same degree of wet air pollution equipment and  controls,  the
process wastewater flow rates from older plants will be higher than from
newer plants.

Two important characteristics of the process wastewaters  are suspended
solids and oil.  The  suspended solids are generally higher from older
plants due to greater maintenance  and poorer housekeeping and control
practices.  The  same  can be said for the oil.  Suspended soi1 ids  evolve
from the powdered substances used  in the compounding area and from the
collection of particulates by wet  air pollution equipment.  The oil is
primarily lubrication and hydraulic oils from in-plant sources, and ex-
tender and fuel oil from run-off in storage areas.  Both parameters can
be treated successfully.  Plant B  is using a sedimentation lagoon to
settle solids collected in the compounding area from wet air pollution
equipment.  It has been demonstrated by Plants A and E that  solids col-
lected in other areas can be separated easily by convential  equipment.
American Petroleum Institute  (API) type separators are being used to
treat oily waste effluents of Plants B, D, and E.

The primary constituents of the process wastewaters are presented in
Table V-4, along with their sources and characteristics.
                                   V-3

-------
                                                  TABLE V - 2
Old Tire Facilities
    (to 1958)
          Minimum
          Maximum
          Average


New Ti re Fac ?1it ies
 (1959 to Present)
          Minimum
          Maximum
          Average
                              Average Valves of Raw Waste Loads for Tire Industry
                               FLOW             COD               S£
                          liters/1,000 kg  liters/1,000 kg  liters/1,000 kg
                          of raw material  of raw material  of raw material
6267.0
386478.0
37000.0
2303.0
43070.0
10500.0
0.088
7.29^
0.7*0
0.083
2.020
0.580
0.001
5.854
1.000
0.032
1.397
0.310
                                                                                  TDS
OIL
1 iters/1,000 kg
of raw material
0.349
105.660
12.000
0.387
1 2 . 980
5.535
1 iters/1,000
of raw mater
0.003
3.363
0.120
0.011
0.187
0.042
kg
ial






Source:   Corp of Engineer Permit Applicati
                                          ons

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                                                       TABLE V - 3

                       Raw Waste Loads of Process Wastewaters From Tire and  Inner Tube  Facilities
                     FLOW1
                             COD
                                    BOD
                                    SS
                                   TDS
                                                                                                           OIL
                     • L. W »T             WWIS              \J \J \J                »J iJ               1 L* sJ               VJ ) l_
        Cate-   1iters/1,000 kg  liter?/!,000 kg  liters?!,000 kg   liters/I,000  kg   liters/I,000  kg   liter?/!,000  kg
Plant   gory    of raw material  of raw material  of raw material   of  raw material   of  raw material   of  raw  material
  A

  B
  c2
  D

  E
  F
  G
  H

  I
New

New

New

New

Old

Old

Old

Old

Old
 290.0

1650.0
 110.0

 700.0

 590.0

4300.0

 769.0
1.57
0.193
0.0^6
2.199
0.067
0.001


0.010

0.000
0.356
0.882

0.013


0.06^

0.017
0.57
0.001
0.520
2.610
 5.12

 0.3739


 3.210

 0.019
19.765
  .075


0.008

0.027
0.650
0.260
0.163
0.172
  1
   Estimated
   No data available from Plant C

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                                                  TABLE V - k


                          The Sources and Characteristics of Process Wastewaters from
                                       the Tire and Inner Tube Industry
Wastewater Type

Soapstone
             Source
Compounding Area:   Washdown and
System Cleanout; Runoff from
Spi11s and Leakage
      Flow
                                                                                1
  Intermittent
0 - 5,7000 Liters
Characterist ics

Suspended Sol ids,
BOD, COD, Oil
Latex Dip
Fabric Dipping Area:  Discharge
of Waste Solution; Washdown; Run-
off from Spills and Leakage
  Intermittent
0 - 200 Liters
Suspended Sol ids,
BOD, COD
 In-Plant Sp?lIs and
 Leakage
All Areas of Plant where Water
Cooled Machinery is used; also
Latex and Soapstone Dipping
Areas
  Intermi ttent
0 - 220 Liters
Oil, Suspended
Sol ids
 Oil and  Solvent Stor-
 age and  Maintenance'
 Area  Runoff
Storm and Washdown Runoff from
these areas
  Intermi ttent
Oil
Ai r  Pollution Equip-
ment  Discharges
Compounding Areas, Tire Finish-
ing Areas
7 - 3^0 Liters/
minute
Suspended Sol ids
 Part  Cleaning Dis-
 charges
Steam Cleaning; Spillages in
Solvent Cleaning Area
  Intermittent
Oil, Suspended
Sol ids
   Maximum and minimum flows from plant visit data are presented here.

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                                                                   DRAFT
Synthetic Rubber Industry

     Gene ra1

Wastewater characterization data was obtained from literature,  EPA  docu-
ments, and company records.  Plant visits (refer to Section VII)  were
made to selected plants to confirm existing data and fill  the data  gaps.
Figures I I 1-3, IN-1*, and  I I I-5 are generalized flow diagrams of  emulsion
crumb, solution crumb, and latex production facilities, respectively;
they indicate the location of water supply and wastewater generation.

Data on total effluent flow and characteristics include utility waste-
waters.  It  is virtually  impossible to determine meaningfully total plant
effluent flows and characteristics exclusive of utility wastes.  It should
be noted here that utility wastewaters are amenable to treatment  by the
existing treatment facilities in use and commonly practiced by the  in-
dustry.

     Emulsion Crumb  Rubber Subcategory

          Flow Analysis

Table V-5 lists the  total  effluent flows for plants producing various
emulsion crumb rubber products based on  a unit of production.  This data
was obtained by plant visits.  Although  three plants were sampled,  six
cases of emulsion crumb production were  studied.  The wastewater con-
tributions of other  facilities included  solution crumb production and
non-rubber commodities.

It can be seen from  Table V-5 that,  for  similar products, separate plants
appear to have different  effluent  flows.  However,  different products at
the same plant seemingly  produce  identical wastewater  flows.  This is due
to the following distinct facts:

      1.  The water use  practices  in  one  plant  for  different  emulsion
         crumb products are based  on one technology, namely  that of the
         company's process design  and  engineering.

      2.  The inability  of the sampling team  to  discern  small differences
         in  effluent flows for different products  at the  same  plant.

 It can also  be noted that there  is no  significant  trend  in wastewater
generation  rate between the  various  types  of emulsion  crumb  rubber pro-
duct  (non-extended,  "hot", oil extended, and carbon black extended).

The average  effluent flow rate  for emulsion  crumb  is 16,600  liters per
metric  ton  (1,000  kg)  of  production.
                                    V-7

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00
                                                         TABLE V - 5




                                      Raw Waste Loads for Emulsion Crumb Rubber Plants
Plant Product
J SBR and NBR Part
01 1 and Carbon Black
Extended
K SBR Part Oil Ex-
tended
K SBR Oil Extended
L SBR Oil and Carbon
Black Extended
' L SBR "Hot", 'ton-
Extended SBR
1. SBR ;:on-Extended
Average Value
FLOW
Liters/1 ,000 kg
15,000
18,500
18,500
16,500
15,500
15,500

COD
kg/ 1,000 kg
11.93
22.23
19.76
8.72
29.24
25. 37
19.63
BOD
kg/1 ,000 kg
N.A.
2.13
2.13
2.84
2.84
2.84
2.56
ss2
kg/ 1,000 kg
3.73
2.30
11.31
3.94
N.A.
11.94
6.64
OIL
kg/ 1,000 kg
2.09
0.13
3.54
0.48
1.31
1.45
1.5
        1
         Includes utility wastewaters.


         Raw waste  load determined downstream of crumb pits, where the suspended solids and oil levels'are reduced.


     N.A.   Data  not available.
                                                                                                                         o
                                                                                                                         30

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                                                                    DRAFT
          Raw Waste Loads

Table V-5 also summarized the raw waste loads for the six cases.   It  can
be seen that the parameter with the highest concentration is COD.   The
BOD values are generally much lower.  The high COD to BOD ratio is in-
dicative of the high resistance of many of the constituents in the waste-
waters to biological oxidation.

The raw suspended solids concentration in the emulsion crumb wastewaters
were determined after separation of the rubber fines in the crumb  pits.
Since all emulsion crumb plants have separation pits, this raw waste  load
data is applicable to the industry.  Much of the suspended solids  con-
tribution is due to uncoagulated latex solids.  The concentration  of  oil
does not appear to be related to the degree to which the crumb rubber is
oil extended.  The oil analysis cited is really "carbon tetrachloride ex-
tractables" and will also include insoluble monomers.

Another significant parameter in emulsion crumb wastewaters is total  dis-
solved solids.  This has two principal sources:

     1.  The crumb coagulation and rinse overflows.

     2.  The utility wastes  (boiler and cooling tower blowdowns,  and
         water treatment regeneration wastes).

Surfactants are another characteristic produced by the emulsifying agents.
The level of surfactants in  the wastewater is considerably lower than the
parameters reported in Table V-A.

          Individual Waste Streams
Table V-6 presents the major constituent loadings of the principal  waste-
water streams in an emulsion crumb plant.  The most significant parameter
Is total dissolved solids which  is produced by the acid and brine coagu-
lation  liquors.  The coagulation liquor and crumb rinse overflows,  along
with the utility wastes, provide the bulk of the total dissolved solids in
the plant effluent.  It can be seen that the quantity of surfactants pro-
duced are much lower than the other parameters.  Surfactants are not gener-
ated in appreciable quantities by waste streams not included in Table V-5.
The suspended solids are much higher than in the total effluent since the
crumb pits remove much of the suspended solids in the crumb rinse overflow.
Removals better than 95 percent are common.  Oil entrained in the rubber
is also removed along with rubber crumb solids.

When comparing the sub-total parameter values of Table V-6 with the average
total effluent loads of Table V~5, it can be seen that the three streams
listed  in Table V-6 are the major contributors to the total effluent.

The spent caustic scrub solution is an extremely low flow  rate wastewater
which has very high COD, alkalinity, pH, and color characteristics.  It

                                   V-9

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                                                          TABLE V - 6



              Raw Waste Loads of the Principal  Individual  Wastewater Streams in an Emulsion Crumb Rubber Plant
                                COO            BOD            SS1             IDS            OIL1       SURFACTANTS
   Wastewater Stream        kg/1,000 kg    kg/1,000 kg    kg/1,000 kg    kg/1,000 kg    kg/1,000 kg    kg/1,000 kg


   Monomer Recovery            0.66           O.lU           0.08           1.26           0.11           0.0001




   Coagulation Liquor Overflow 1.30           N.A.           N.A.          ^6.25           0.10            N.A.




1s  Crumb Rinse Overflow2       6.39           0.*+6          33.^          ^2.33           1.^6          0.0077
        Sub-Total              8.35           0.60          33.52          39.7^           1.67          0.0078
        Raw waste load determined prior to crumb pit, where the suspended solids and oil  levels are reduced.
       2
        In one case, the crumb rinse overflow is combined with the coagulation liquor overflow and discharged as one

        combined stream.

   N.A. Data not available.
                                                                                                                          o
                                                                                                                          73

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                                                                    DRAFT
is not, however, a significant waste stream when combined in the total
effluent.   It is usually bled-in at low flow rates into the effluent.

Area washdown and equipment clean-out wastewaters are highly loaded with
COD and suspended solids, and, by nature, are intermittent in flow.  They
cannot be characterized because they are generated on an irregular basis
and have greatly variable concentration loadings.

Chromium and zinc are present  in low concentrations  (1 mg/L) in the final
effluent.   They are present due to cooling water treatment, and can be
eliminated by substitution of  chromium-free corrosion inhibitors.  Heavy
metals from catalysts and other reaction ingredients are not present in
measurable concentrations in emulsion plant wastewater effluents.

     Solution Crumb Rubber Subcategory

          Flow Analysis

Table V-7 presents the  total effluent wastewater  flows for  facilities
producing various solution crumb rubber products.  The flow data is given
in terms of liters per  kilogram of production.  Five plants were visited
and eight types of solution crumb product were  sampled.  Some plants are
multi-product facilities, and  the contributions of the solution crumb
facilities were accounted for.

Table V-7 shows that  there  is  no discernible  difference  in  the effluent
flows between types of  product.  There  appears  to be more correlation
between products at the same  plant site.  This  is similar to the findings
for emulsion crumb  rubber production.

One plant  (Plant M) has a considerably  lower  effluent  flow  than all the
other  facilities.  The  apparent  reason  for  this difference  is  the  use of
a  special  rubber-finishing  process which  generates very  little  or  no
wastewater.

The average effluent  flow for solution  plants is  similar to emulsion
plants, and typically approximates  16,600 liters  per metric ton of pro-
duction.

           Raw Waste  Loads^

Table  V-7  also  presents the raw waste loads for the  four main  parameters.
 It can  be  seen  that  the constituent  levels  are approximately one  half  of
those  present  in  emulsion crumb wastewaters.   This  supports literature
and company data  which  indicate that the solution production processes
are "cleaner"  than  their emulsion counterparts.  The main factor behind
this  is the absence of coagulation  liquor and uncoagulated latex.   The
COD to BOD ratio  is  high which indicates that a considerable proportion
of the raw wastewater components are not readily biologically  oxidizable.
                                    V-11

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                                                       TABLE V - 7


                                    Raw Waste Loads  for Solution Crumb Rubber Plants
Plant
K
K
L
L
M
: n
N
0
Product
SBR Oi 1 Extended
SBR Carbon Black Ex-
tended
PBR Oi 1 Extended
SBR Non-Extended
PBR Non-Extended
1 R Non-Extended
PBR Part Oil Extended
PBR, IR EPDM
Part Oil and Carbon
FLOW
Liters/1 ,000 kg
10,500
17,800
28,500
14,700
3,400
11,900
11,900
29,000
COD
kg/I ,000 kg
4.04
20.80
11.40
13.28
0.17
3.61
3.01
5.33
BOD
kg/ 1,000 kg
0.09
0.18
1.55
0.82
0.06
1.37
1.37
3.57
ss1
kg/ 1,000 kg
0.81
2.20
5.72
1.79
0.05
N.A.
5.38
3.71
OIL
kg/1 ,000 kg
N.A.
N.A.
2.43
1.43
0.07
0.01
2.32
0.23
               Black Extended


               Average Value                                   9.03             1.13            2.81             1.03




    1
     Raw waste load determined downstream of  crumb  pits,  where  the suspended  solids and oil  levels are reduced.

N.A. Data not available.

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                                                                    DRAFT
The total dissolved solids content of solution crumb wastewater is  con-
siderably lower than for emulsion crumb plants.  This again is  mainly due
to the absence of the coagulation liquor.

Surfactant concentrations in the total plant effluent are low.   Surfactants
are used to de-agglomerate the crumb rubber during coagulation  and  rinsing.

The solvent recovery systems do not produce any significant effect  on the
COD or BOD content of the effluent.

One plant (Plant M) has considerably lower loadings than the others.  This
is probably due to the fact that rubber for non-tire use is produced at
this plant.  This rubber is used to manufacture impact-resistant resins,
and its quality and production controls are extremely critical.  In ad-
dition, special finishing equipment appears to be used.

          Individual Waste Streams
The crumb rinse overflow produced at a solution crumb plant is similar
to that produced at an emulsion crumb plant, with the exception that un-
coagulated latex is not present.  The suspended solids, mostly crumb
rubber fines, are similar to those  in emulsion crumb rinse overflows;
the crumb pits produce the same reductions.

The monomer and solvent recovery wastes are comparable to the monomer
recovery wastes from emulsion plants.  Although heavy slops are produced
in some plants, these are usually disposed of by drumming or incineration,
Since monomer purities must be high, recovered butadiene, for example,
Is returned to the monomer supply plant and has no  impact on the solu-
tion crumb rubber wastewater.

Equipment clean-out wastewaters are less of an environmental problem in
a solution plant because much of the processing equipment must be kept
dry or water free.  Area washdowns  are similar in volume, but do not con-
tain latex.  These washdowns do pick-up rubber solids and oil from pumps
and machinery areas.

The spent caustic scrub solution, where used,  is  identical to that used
in emulsion crumb production.   In plants where emulsion and solution
crumb rubber is produced, the same  caustic scrub  system is used for both
facilities.

Catalysts and other reaction  ingredients do not produce discernible
quantities of heavy metals or toxic constituents.   Chromium and zinc in
cooling tower blowdown are present  in  some plant  effluents, but in very
low concentrations.  These can  be eliminated by using chromium-free cor-
rosion inhibitors.
                                   V-13

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                                                                   DRAFT
     Latex Rubber Subcategory

          Flow Analysis

Table V-8 lists the total effluent flows for latex rubber plants.   Only
two plants are presented, but the similarity between the data  values  is
good.  Latex plants are generally part of larger complexes,  and  flow
data for latex operations is difficult to obtain.  The flow  from latex
plants appears to be lower than from either emulsion crumb or  solution
crumb facilities.  The major flow contributions at latex plants  originate
with equipment cleaning, area washdown operations, and waters  from vacuum
pump seal systems.

          Raw Waste Loads
The raw waste loads of latex plant wastewaters are considerably  higher
than either emulsion or solution crumb plants.  Equipment cleanout  and
area washdowns are frequent due to smaller produce runs, and considerable
quantities of uncoagulated latex are contained in these wastewaters.  The
high COD to BOD ratio is typical of all synthetic rubber subcategories
and underlines the resistance to biological oxidation of the wastewater
constituents.  Oil concentration is lower than in emulsion or solution
crumb facilities and is contributed by separable monomers, such  as  styrene,
in the wastes.  The suspended solids in the effluent are due mainly to
uncoagulated latex.  Total dissolved solid levels are lower than for
emulsion plants because of the absence of the coagulation liquor stream.
Surfactants are present, but in much lower concentrations than the  other
parameters.

          Individual Waste Streams
Tank, reactor, and filter cleaning produces considerable quantities of
wastewater.  These are characterized by high COD, BOD, and suspended
solids.   In addition, unloading and product loading areas and general
plant areas are frequently washed down.  The characteristics'of these
wastes are similar to those produced by usual equipment cleaning in this
industry.  Vacuum pump seal waters contain small quantities of organics
which produce moderate levels of COD from the vacuum stripping operation,
The stripping condensates contain condensed monomers.  Most of these
monomers are decanted from the water and re-used.  The water layer over-
flow from the decanter has high COD and BOD concentrations.

Spent caustic scrub solution is an extremely low flow waste and has simi-
lar characteristics to spent solutions produced in emulsion crumb and
solution crumb plants.

-------
-!.A.  Data not available.
                                                  TABLE V - 8
                                    Raw Waste Loads for Latex Rubber Plants
Plant
                 Product
                                       FLOW
                        COD
                 BOD
                SS
               OIL
liters/1,000 kg     kg/1,000 kg      kg/1,000 kg     kg/1,000 kg    kg/1,000 kg
              SBR and NBR
                        36.37
                 5.61
                6.70
               N.A.
              SBR
     12,500
33.52
5.01
5.63
0.33
Average Value
                                         5.31
                                 6.17
                               0.33
                                                                                                                   o
                                                                                                                   73

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                                                                 DRAFT
                                 SECTION VI I

                      CONTPxOL AND TREATMENT TECHNOLOGY


Survey of Selected Plants
     General Approach and Summary

In order to review and fully evaluate the wastewater control  and treat-
ment technologies used in the rubber processing industry, selected plants
were visited to conduct operation analyses, review water and  wastewater
management programs, and evaluate wastewater treatment facilities.   The
plants were selected as being exemplary or advanced in their  wastewater
control and treatment technologies, based on effluent'and treatment data
from the technical literature, EPA documents, Corps of Engineers Permit
to Discharge Applications, and individual company treatment data.

Plants producing passenger tires(both bias and radial ply), truck tires,
camelback ,  and inner tubes were visited and studied to determine if the
type of product affected the quality and quantity of wastewater streams
and/or the control and treatment technology employed.  Both single-pro-
duct and multi-product plants were included so that the effects of  com-
bined  lines on the plant wastewaters could be evaluated; likewise,  plants
of various sizes were studied to determine the impact of production
levels.  Age was a major consideration because determination  of the
effect, if any, of newer processing technology and machinery  on the con-
trol and treatability of process waste streams was one of the principal
objectives of the invest i gat i've phase of this project.  Table VI 1-1
is a summary of the products manufactured, raw material usage, and  waste-
water control and treatment technologies utilized at the tire and inner
tube plants visited.

In the synthetic rubber production segment of the industry, the field
visits included plants employing emulsion and solution polymerization
processing methods and involving all types of synthetic rubber products:
"cold crumb", "hot crumb", non-extended, oil-extended, carbon-black-
extended, and latex rubbers.  As in the tire and inner tube segment,
the effects of single- and multi-product lines, plant size, and plant
age on wastewater volume and characteristics and related control and
treatment technology were evaluated.  A summary of the products, processes,
production capacities, and wastewater control and treatment technologies
of the exemplary synthetic rubber plants visited is presented in Table
VII-2.
                            VI 1-1

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Plant
             Product
             Passenger Tires,
             Implement Ti.res,
             Front Tractor Tires

             Passenger Tires,
             Industrial Tires
             Passenger T ires

             Passenger Tires, Truck
             Tires, Tractor Tires,
             Camelback
             Passenger Tires,
             Truck Tires
             Passenger Tires, Truck
             Ti res. Inner Tubes,
             Camelback

             Passenger Tires,
             Truck Ti res
             Truck Tires, Industrial
             Tires
              Inner Tubes
                                     Table VI1-1

Wastewater Control and Treatment Technologies at Exemplary Tire and Inner Tube Plants

                             Control Measures
   Raw Material Usage
       (Kg/day)

        120,000
        310,000
        s&o.ooo
        210,000
        681 ,000
        2<»6,000
                                               75,000
Recirculation of Soapstone,
Absence of Drains in Dirty
Areas

Recirculation of So.ipstone,
Baffled Oil  Separator for Oil
Storage Area, Absence of Drains
in Dirty Areas

Recirculation of Soapstone

Recirculation of Soapstone,
Oil Separator, Loca! Oil Sumps
Blockage of Drains, Local Oil
Sumps and Gravity Separators,
Curbing of Soapstone Area, Re-
circulation of Soapstone

Recirculation of Soapstone,
Oil Sump for Oil Storage Area
Recirculation of Soapstone,  Oil
Sump and Curbs for Oil  Storage
Area

Recirculation of Soapstone
                             Containment of Soap  and  Soapstone
                             Solutions
                                      Primary Effluent
                                      Treatment
Sedimentation and
Holding Lagoon


Sedimentation and
Lagoons
Primary Settling Basins

Gravity Separator for
Boiler Slowdown, Some Water
Treatment Wastes and Wash-
down of Soapstone Area

None
                                                                   Primary  Settling Basin
                                                                   and Clarifying  Basin
                                                                   None
                                                                   Sedimentation Basins for
                                                                   Boiler  Slowdown, Cooling
                                                                   Tower and Water Treatment
                                                                   Wastes

                                                                   None
                               Secondary Effluent
                               Treatment
No Discharge due to Spray
Irrigation and Evaporation
of Wastewaters

None
None

Discharge of Some Water Treat-
ment Wastes to Municipal  Treat-
ment FadIi ty
                               Discharging  of  Process Waste
                               to  Municipal Treatment Facility
                                                                                                 None
                              Discharge of Treated Wastes
                              to Municipal Treatment Facility
                                                                                                                                       None

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                                                                      Table VI1-2

                                  Wastewater Control and Treatment Technologies at Exemplary Synthetic Rubber Plants
Plant Product
J Crumb SBR
Crumb NBR
K Crumb SBR
L Crumb SBR
Crumb, hot SBR
Crumb PBR
Crumb SBR
M Crumb PBR
N Crumb IR
Crumb PBR
0 Crumb PBR
Crumb IR
Crumb EPOM
P Latex SBR
Latex NBR

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                                                                  DRAFT
     Tire and Inner Tube Plants
           Plant A

This plant, built in 1961 and located In an arid rural  community,  pro-
ducies passenger tires, small-implement tires,  and front tractor  tires.
Production rate  for passenger tires at the time of the visit was
12,000 units per day.  In addition to the normal tire processing and
production lines, this plant has a latex fabric-dip operation.   Raw
material consumption was over 120,000 kg(264,000 Ibs) per day.

The actual production facility occupies approximately ^0 acres of  land.
The plant boundaries surround another 350 acres of land currently  devoted
to agricultural  use.

The only source of raw water supply is well water.  It is used for cooling,
steam generation, domestic use, and all other plant needs.

The principal process wastewaters from this plant are water and  steam
leakages, and wash waters from the cleaning of equipment and general
work areas.  Water leakage occurs at various water-cooled machinery
units,  including mills, Banburys, tread extruders, and tread-cooling
tanks.   In addition, water can escape from the hydraulic water system
used in  the Banbury and press areas.  Water and steam occur in the process
wastewater in the press area as the result of broken seals or  failing
bladder  bags.  Oil and solid matter which have collected on the  floors
are carried along by these various water streams into the area drainage
system.  The oil is lubrication oil which has dripped or leaked  from  oil
seals on mills,  pumps and like equipment, from open gears, from  gear  boxes,
and from the hydraulic water system.  Additional oil and soild materials
result from leakages at the Banbury dust and oil rings.

Daily washdowns include steam and solvent cleaning of the tread  books
and miscellaneous machinery parts and the cleaning of the latex  dip  tank.
Weekly cleanups, which occur on the weekends(non-production days), include
washdown of the steel grates in the soapstone area.

This plant was specially laid out and engineered so as to keep  spills and
leakages from becoming a problem.  Drains are non-existent in the soap-
stone area and  in many of the mill areas.  Removable steel grates have
been provided in the soapstone dip area so that spilled soapstone solution
will not create a work hazard.  Housekeeping practices and schedules  have
been set up to keep leaks and spills of lubricating oil on the  floors of
the flant to a minimum.  When steam and water leakages do occur, they are
directed(along with all other process and non-process wastes)  to a collec-
tion pond.  Equipment-cleaning wastewaters are also discharged  to this pond.
                            VI 1-1

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                                                                 DRAFT
The principal non-process wastewaters are boiler and cooling pond
blowdowns.  In addition, there is a hot-water-sump overflow.  The  hot-
water sump is used as a collection point for recycled press  cooling
water.  Contaminants in these wastes are suspended and dissolved
sol ids.

End-of-pipe treatment at this plant includes pH control  and  the lagoon-
ing of all effluents, both process and non-process.  The wastewaters,
after pH adjustment, are directed to the 11 million liter(3  million
gallon) collection and storage pond.  The residence time in this pond
is approximately four days.  Settling of suspended solids and the
reduction of both COD and oil occur during this period of time.  From
here, the wastewaters are fed to a second pond.  Water leaving the
second retention pond can be used for any of three functions.  It can
be used for  irrigation on the company-owned farm acreage around the
production facllity(its primary function),  it can evaporate, or it
can percolate  into the sandy ground below the pond.   (The water table
at this plant  is approximately 76 meters(250 ft.) below the surface.)

In addition to containment of all process and non-process wastewaters,
all storm runoff from within and around the plant confines  is directed
to and contained  in these  lagoons.

          Plant B

This  plant,  located  in a  rural area,  started operating  in 196^.   Plant-
owned ground  is now almost entirely  utilized by processing  and ware-
housing buildings, parking lots, and  wastewater treatment facilities.

The facility  produces  passenger  tires and heavy off-the-road  tires.
Production rates are currently  running  at 2k,000 passenger  and  2,000
off-the-road  tires per day.

Water for all  plant  uses,  including  makeup  for  the  cooling  towers, boiler
and various  dipping  solutions,  is  supplied  by  the municipality.

The principal  process  wastewaters  from  this plant are:   water and steam
 leakages,  runoff  from  the process  oil storage  area,  and discharges from
wet air-pollution  control  equipment.

Water and steam leakages occur  in the press room of both the passenger-
 tire  and  truck-tire  facilities.   These  streams become contaminated with
oil  scavenged off machinery  parts  and the floor.  Runoff from the oil
 storage area is continuous due  to the placement of a steam  blowdown pipe
 nearby;   oil  is scavenged from  the area and becomes entrained with the
 condensate wastewater  stream.
                              VII-5

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                                                                   DRAFT
Wet scrubbers are used to control air emissions from the compounding area
and from the green tire painting area.  Collectively, these scrubbers
represent the largest single discharge in the plant.  Contaminants
include COD and suspended solids, as well as some oily matter.

Maintenance and housekeeping practices at this plant are directed at
keeping leakage at a minimum and wel1 contained.  Runoff from the process
oil-storage areas is pretreated  in a baffled oil separator chamber before
flowing to the end-of-pipe treatment facilities.  The separator unit ef-
fectively removes oil from the small volume of water in the influent.

Water discharged from air pollution equipment passes into the plant's end-
of-pipe treatment facility untreated.

The principal non-process wastewaters are boiler and cooling tower blow-
downs, and water treatment wastes; these are segregated from the process
wastewaters and are discharged, without subsequent treatment, into the
storm drainage system.

In addition, there are blowdowns from various presses throughout the plant;
these contain COD, suspended solids, and dissolved solids.

End-of-pipe treatment at this plant  involves the use of two lagoons.  The
wet scrubbers and steam blowdowns flow into the first lagoon, which  is used
to separate settleable solids and separable oil.  This pond has a surface
area of 0.52 acres and a baffled effluent weir.  Wet scrubbers, and some
once-through cooling water flow  to the second lagoon.  This has approximately
O.Jk acres of surface area and is also used to  remove separable solids and
oil from the influent.

          Plant C

This production facility consists of two plants, the older of the two
dating from 19^5 and the newer one coming on stream within the last decade.
The facility is located  in an  industrialized area on the fringes of an
urban center.  Most of the land  within the plant boundaries is occupied
by production buildings and by the necessary auxiliary buildings, waste
treatment facilities, and parking areas.  The facility produces only passen-
ger tires(both bias ply and radial).  Raw material consumption is approxi-
mately 3^9,000 kilograms(770,000 pounds) per day.  Exact unit production
rates are unknown, although the  figure is known to be well above 20,000
units per day.

The principal process wastewaters are water and steam leakages, overflow
from various sumps, and  runoff from oil  storage areas.  Water leakages
occur throughout the plant wherever there is water-cooled machinery, such


                              VII-6

-------
                                                                   DRAFT
as mills and Banburys.  Water and steam leakages occur In the press
area due to leaking seals, failing bladder bags, and leakages in the
hydraulic water system.  The process wastewaters scavenge oil and solid
materials, which flow to the nearest drain.  Oil and solid material
accumulate on the floor and in the various machinery basins due to drip-
ping and leaks from the Banbury dust rings, mill and pump oil seals,
open gears, and the hydraulic water system.  Runoff from oil  storage areas
occurs during rainstorms and washdowns, and is another source of oily
process wastewater.

This plant at one time had a process wastewater discharge of soapstone
solution.  After extensive studies showed that this solution caused
excessive BOD and total solids in the wastewater, this discharge
was eliminated.  The current practice is to recycle this solution.

Wastewater streams resulting from the use of other solutions in the plant,
such as the latex dip, have also been eliminated.  These streams are
dumped into a sump, which is periodically emptied into drums and sent
to a landfi11 s ite.

The principal non-process wastewaters are boiler and cooling tower blow-
down, once-through tread cooling water, and water treatment wastes.   In
all cases, dissolved solids are a problem, and suspended solids will be a
problem in the water treatment waste and boiler blowdown.

Process wastewaters and all the non-process wastewaters(with the exception
of boiler blowdown) are combined and then directed to a primary treatment
facility.  This treatment facility consists of two settling basins, oper-
ating in parallel.  Each provides 24 hours retention for the waste streams.
Settleable solids are removed periodically(approximately every two years),
and floating oil is removed by a belt filter.  Boiler blowdown and sani-
tary wastes are treated in a package extended aeration  sanitary waste-
water treatment plant.  All treated wastewaters are discharged to the
river.

          Plant D

This plant, started up  in the early 19^0's,  is  located  in an urban,  indus-
trialized area.  It has recently undergone extensive modifications, and,
therefore, production  levels are not well established.  However, past data
indcate that the plant  is producing 22,000 passenger, truck, and tractor
tires per day.  The plant also produces camelback.  Raw material consump-
tion is in the neighborhood of 840,000 kilpgrams(1.85 million pounds) per
day.

Raw water is supplied by the municipality  and from company-owned deep
wells.  The city water  is used to supply  domestic and air conditioner

                              VI 1-7

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                                                                   DRAFT
cooling needs.  The wells supply once-through cooling water,  cooling tower
makeup, boiler feed water, and processing solution makeup.

The principal process wastewaters from this plant include:   water leakages,
steam leakages, a weekly washdown of the soapstone recirculation system,
equipment and floor cleaning washdowns, and minor runoff from the oil
storage area.

Water leakages arise from the oil seals and open gears on mill calendars
and pumps and from the hydraulic water system used in the Banburys and
presses.  Steam leakages occur  in the press room from broken or leaking
seals and failing bladder bags.  Both types of leakage are heavily laden
with oil picked up from the seals and from lubricating oil  drippings.   The
soapstone recirculation system  is cleaned out once a week,  and the effluent
has high BOD and suspended solids loadings.  The floors are cleaned with
an automatic sweeper that uses  a soapy water solution as a cleaning agent.
Drainage from this system also  has a high BOD and suspended solids load-
ings.  Steam cleaning  is used for small machinery parts, and the discharges
are significantly contaminated  with oil.

Water and steam leaks  in the press area are pumped to an oil separator,
where the floating oil  is removed and disposed of by an outside contractor.
Water  leakages  in the mill area are kept at a minimum by careful house-
keeping and maintenance practices, and do not appear to be a serious pro-
blem.  Runoff from oil  storage  areas  is collected  in sumps, which are
pumped out on an "as required"  basis.

Floor-cleaning machinery discharges and steam-cleaning discharges flow
into the sanitary sewer.

The principal non-process wastewaters are boiler  and cooling  tower blow-
downs, water  treatment  wastes,  and once-through  cooling water.   In  the
first  three  cases, dissolved  solids constitute a  problem.  Boiler blowdowns
and water treatment wastes may  also contain  high  concentrations  of  suspended
solids, depending on the  treatment process being  used.  COD  and  pH may also
be problems.

There  is no  end-of-pipe wastewater treatment  facility  which  covers  the
entire process  wastewater  stream.  Some  non-process  wastewater  and  the
weekly dump  of  the  soapstone  slurry are  directed  to  a  holding basin
for  removal  of  settleable solids before  discharge.
                               VII-8

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                                                                    DRAFT
           Plant E
 This facility which was started up in 1920, is a sprawling complex
 occupying 25 major buildings and more than Ik acres of ground.   Although
 it is located in a very congested urban area, the plant boundaries en-
 close approximately 13 acres of open ground.

 The plant was originally set up to produce many rubber products,  includ-
 ing tires, belting, and inner tubes.   However, with the passage  of time
 and because of specialization, production of all  rubber products  with the
 exception of tires has been discontinued.  Current production  levels are
 10,400 passenger tires per day and 4,400 truck tires per day.  Total raw
 material  consumption is 210,160 kilograms(462,900 pounds)  per day.

 Production facilities are located in  three buildings.   The Banburys and
 mills of  the compounding operation and the presses of the  molding and
 curing operations are located in separate buiIdings(Banbury and  Press
 Buildings).   The mills, extruders, calendars,  etc.  of the  tread and bead
 formation lines  and of the fabric-coating operations are all located in a
 large buiIding(Rubber Mill  Building)  located between the compounding and
 curing buildings.  The buildings are  interconnected so as  to approximate
 a  continuous product ion line.   Fabric is shipped  to this plant pretreated,
 and no additional dipping  operations  are performed.

 The plant has two separate sources of raw water supply:  well water and
 municipally  supplied  water.   The well  water  is used  primarily for cooling
 tower makeup, and the municipal(city)  water  is used  as  boiler makeup,
 after treatment.  The city water is also used  in  making  the soapstone
 and other solutions   used  in  tire manufacture.

The principal process  wastewaters  include water and  steam  leakages, steam
 cleaning,  and wet air-pollution  equipment discharges.  Water leakages
 arise from water-cooled machinery,  such  as mills, Banburys,  tread extruders,
 and tread  cooling tanks.   In  addition, water can  escape  from the  hydraulic
water system used in  the Banbury  and  press areas.  Wjter and steam leakages
occur  in  the press building due  to broken  seals and  failing bladder bags.
These wastewater  streams are heavily  laden with oil  picked  up from the seals
and from  floor areas  and basins.   Machinery parts such as gears and bearings
are cleaned with  steam, and the  resulting waste contains both oil and suspend-
ed solids.  Grinding operations within the plant  are equipped with wet  par-
ticulate collectors.  Effluents  from these collectors are small  in volume
but contain a high concentration of heavy  rubber  as  suspended particles.
Zinc and chromium are used as corrosion  inhibitors and will therefore be
present in the collector discharge.
                              VI 1-9

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                                                                    DRAFT
 Leakages,  both  steam and water, are collected in two sumps, one located
 In  the  press building and  the other in the rubber mill building.  These
 sumps separate  the oil, and the resulting underflow is released to a
 sanitary sewer.  Sanitary  sewers within the plant are connected to the
 municipal  sanitary sewer system and eventually to the municipal waste-
 water treatment plant.  Oil from the sump is removed periodically by
 maintenance personnel.

 Steam cleaning of machinery parts is carried out in a non-congested out-
 door area  of the plant.  Curbing and concrete flooring are used to direct
 the wastewaters into three small basins connected in series.  The area
 is  supplied with a roof to prevent storm water from diluting the wash
 water and  upsetting the settling operation.  Storm runoff from this area
 is  directed into the storm-water catch basins.  These catch basins act
 as  gravity separators, allowing the separable suspended s.olids to settle
 out and oil to float to the surface.  The effluent from the basin dis-
 charges into the sanitary  sewer.  Solids and oil are removed from these
 basins periodically.

 The effluent from the wet particulate collectors flows into a set of
 similar settling basins, where most of the solids are settled out.  The
 effluent then discharges into the sanitary sewer.  These basins are
 equipped with automatic solids-removal equipment.

All solids and oil removed from the various treatment facilities are
 containerized and disposed of by contract hauler to a landfill.

 The principal non-process wastewaters are boiler and cooling tower blow-
 downs, and water treatment wastes. In all cases, dissolved solids are
 present in the wastewater, generally at high concentrations. Boiler blow-
 downs and water treatment wastes also contain high concentrations of sus-
 pended solids.  The water makeup for the cooling tower which supplies cool-
 ing water to the press building is treated with a corrosion inhibitor con-
 taining chromium and zinc, and these metals are present in the blowdowns.

At this plant,  there is no end-of-pipe treatment facility.  All contam-
 inated process  and non-process wastewaters (with the exception of the main
cooling tower)  are discharged to a municipal  treatment facility.

          Plant F

This production facility,  built in 1928, is located in a minor urban
area,  on a  large (more than 2.8 billion square meters (700 acres)) plot
of ground,  of which the actual production facility occupies only a small
proportion.

Production  lines include passenger tires, truck tires, inner tubes, flaps,
bladders, and camelback.  The plant,  as currently designed, is divided up
 Into separate product  unit buildings  for each end product.  Daily production
rates  are currently running at 40,000 passenger and truck tires, 36,000

                              VII-10

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                                                                   DRAFT
inner tubes, 13,000 bladders and flaps,  and 60,000 Ibs.  of camelback.
Daily raw material consumption is 681,000 kilograms (1.5 million  pounds).
This plant utilizes river water for production and utility purposes and
city water for domestic purposes.

The principal process wastewaters from this plant include:  water and  steam
leakages and overflows, runoff from process oil-storage  areas,  soapstone
solution spillages, and wash downs  and runoff from process or  storage areas.

Water leakages occur at various water-cooled machinery units,  including
mills, Banburys,  tread extruders, and tread cooling tanks.   In  addition,
water can escape  from the hydraulic water system used in the  Banbury  and
press areas.  Water and steam  leakages occur in the press  area  duetto
broken seals, failing bladder  bags, and overflows from the collection
pumps,  051 and solid matter which have collected on the floor  are
scavenged by these various water streams and are carried untreated to the
drainage system.  Oil on the floor spaces  is lubricating oil  which has
dripped or  leaked from oil  seals on mills, pumps, and like equipment,
from open gears,  from gear  boxes and  from  the hydraulic water system.
Oil and solid materials  result from leakages at the Banbury dust and
oil rings.

Soapstone solution which has  spilled  and dripped  on the floor is^washed
down periodically and enters  the drainage  system  untreated.  Typical
contaminants are  BOD,  suspended solids,  and  dissolved solids.

Washdown  water  and  storm runoff are allowed  to  drain  through the process
oil-storage area, where  oil  is scavenged and carried  to the drainage  system.
Before  discharge  to the  sewer, this stream is  pretreated  in a baffled
sump, where oil  is  separated,  removed by a belt filter, and disposed  of
at a  sanitary  landfill.  The  sump  is  baffled,  but provides no excess
capacity  for oil  separation during a  storm runoff.

The aforementioned process wastewaters are mixed with non-process waste-
waters  in the  drainage system.  The non-process wastewaters  include  once-
 through river  water, boiler blowdown, and  a small overflow from  the  num-
 erous small pump sumps located throughout  the plant.

 End-of-pipe treatment facilities consist of a two-stage detention basin.
 The primary facilities provide approximately 2,000 square meters for
 bottom and surface removal of  separable materials. During dry-weather
 flow the surface loading is ^9,000 1iters/day/sq. m. (1,200 gals/day/sq. ft.),
 which is too high for effective treatment of wastewater of  this  character.
 It is estimated  that the facilities provide little or no treatment  whatso-
 ever during periods of significant runoff.  The primary facilities  are-
 followed in series by a pond  baffled down the middle to retain floatable
 materials.  Some additional settleable materials are also contained, but
 no facilities are provided for  removal of floatable or settleable materials
 except on  "as required" basis.
                                vii-n

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                                                                    DRAFT
The secondary pond provides a theoretical  detention time  of  twelve  hours
during dry-weather flow.  However,  this  is significantly  reduced  by short
circuiting attributable to the location  of the inlet and  outlet connections.
Surface loading on this pond is adequate for removal of separable materials
during dry-weather flow as well as  during storm weather runoff conditions.
However, the surface of the pond is subject to wind turbulence, which  may
remix the separated floatable materials.

          Plant G

This production facility, built in 1928 is located  in a highly  congested,
highly  industrialized suburban area.  Built and originally operated by
another company,  it was bought by the current operator in the 1930's and
converted to tire manufacture.  The facility produces passenger  and truck
tires.  Daily production rates are currently running at  18,300  passenger
tires and 1,150 truck tires.  Raw material consumption is over  2^6,000
ki lograms (5^-1 ,000 pounds) per day.

The plant occupies approximately 280 million square meters(70 acres) of
ground, with most of the land occupied by production and  warehousing
buildings.  Because of  the  industrial development around  the plant, there
are no  foreseeable plans for expansion at the current facility.

Well water  is the only  source of raw water supply to this plant,  and is
used for all plant water needs.

The principal process wastewaters from this plant are water and steam
leakages, and washdown  and  runoff from the machine  shop area.  Water
leakages occur  in the press are due to broken or  leaking seals and
failing bladder bags.   These process wastewaters  scavenge oil and  solid
materials as they flow  to the drains.  Oil and solid materials accumulate
on the  floor and  in various machinery basins due  to drippings and  leaks
from the Banbury  dust  rings, mill and pump oil seals, open gears,  and
the hydraulic water system.   In the machine shop  area, steam used  for
cleaning of parts and  runoff from painting and washdown operations is
allowed to enter  the storm  drain;  these wastewaters may be contaminated
with both oil and solid material.

Runoff  from the oil-storage  is  not a problem  in this plant, because the
drain  in this area has  been  surrounded  by  a curb  which prevents  normal
spills  from entering the sewer  system.    In addition, there  is a straw
filter  covering the drain  inlet.  Oil that  spills in this area is  pumped
into a  special  storage  tank which  is periodically emptied;  this waste oil
is sent to a landfill  site.

Both process and  non-process wastewaters  flow  to  a  common sewer, where they
are discharged  to the municipal storm sewer.   Before  leaving the plant, all
wastewaters must  flow  through  a shredded  plastic  filter which retains float-
able oil.  This filter  is  replaced periodically.   The oil trapped  behind
the filter  is also  removed  periodically.

                               VII-12

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                                                                  DRAFT
          Plant H

This facility, built in 19^5, is located in highly congested  and  highly
industrialized area.  Essentially all of the plant-owned land is  utilized
for production and warehousing facilities, utility systems,  and wastewater
treatment facilities.  Expansion of the current plant would  necessitate
the leasing of land from adjacent landowners.

The facility produces truck tires, industrial and farm tires, giant off-
the-road tires, and various other minor products including bladders and
rubber gaskets for the curing presses.

Current production levels for the major products are 6,850 truck  tires
and 2,*t30 industrial, farm and giant off-the-road tires per day.

Sources of raw water include surface water from a nearby river and muni-
cipally supplied water.  Surface water  is used as the primary source of
once-through cooling water and for makeup to the cooling tower and other
recirculating water systems.  City water  is used as  for boiler feed
water and also as a backup for the surface water  in  recirculating water
systems.

The principal process wastewaters are  from water and  steam leakages from
presses and mills.  These  leakages occur  at  the oil  seals of mills, at the
hydraulic water system, and  at the curing presses.   The leakages scavenge
oil and soilds spilled  in press  and  mill  basins due  to open  bearings and
lubrication of machinery parts.

The principal non-process wastewaters  are the  overflows and  blowdowns from
various recirculating water  systems,  the  once-through cooling water, boiler
blowdown, and water  treatment wastes.   Contaminants  in  these wastewaters
include suspended and dissolved  solids; these  wastewaters also require pH
adjustment.

Whenever possible, oil  that  leaks or spills  onto  the floors  or basin areas
is collected.  This  oil either  is drummed and  sent  to a sanitary  landfill
or  is  filtered and  reused.   Plant engineers  are  currently examining the
feasibility of using this  oil  as a  fuel admixture in the  boilers.  With the
oil on  the  floor  kept at a minimum,  less  can be  scavenged by water or steam
contact.  There  is  however,  no  treatment  at  this  plant  for the oily waste-
waters  that do occur; they would be  discharged with either once-through
cooling water or  the utility wastewaters.

There  is no end-of-pipe treatment for the once-through(non-contact) cooling
water;  except for oil picked up  due to leakages  and spills  this  water is
                              VII-13

-------
                                                                  DRAFT
uncontaminated, and discharges back to the river.   Discharges  from
the other utility systems, such as boiler blowdown, cooling tower blow-
down,  and water treatment wastes are directed to an effluent basin,  where
settleable solids are removed.  The surface loading is (600 1 iters/day/sq.
meter),  and the theoretical detention time is 24 hours.   There is no provision
for continuous removal of solids or oil.  Discharges from the effluent
basin  are directed via a sanitary sewer system to a municipally operated
treatment plant.

          Plant I
This plant, built in the late 19th century, is now involved in the manu-
facture of inner tubes, valves, flaps, and simlar items associated with
automobile tire applications.  Raw material consumption is approximately
75,000 kilograms (165,000 Ibs.) per day.  This amounts to an equivalent of
over 50,000 inner tubes per day.

The production facilities occupy a multi-story building in the downtown
area of a major city. There has been no expansion at this plant for the
last fifty years.  Because of the extremely tight land situation and
because of the relatively stable tire-tube market, no expansion is planned
In the foreseeable future.

All the raw water used  in this  facility  is provided by the city.

Principal process wastewaters are water  and steam leakages, and the wash-
down of dusty areas within the  plant.  These  streams become contaminated
with oil and dust that  is scavenged  from floor and machinery  areas.  These
wastewater streams flow into a  sewer  and  are  combined with non-process
wastewaters before discharge from the  plant.  Non-process wastewaters
include once-through cooling water,  cooling tower and boiler  blowdowns,
and water treatment wastes.  Suspended solids will be present in  substan-
tial quantities  in the  blowdowns and  water treatment wastes.

The city sewers  are combined sewers;  consequently, domestic,  process,  and
non-process wastewaters are mixed and  treated in the municipal wastewater
treatment  faci1ity.

The housekeeping practices  in  the plant are  unique.   Spillages of soap and
soapstone  solutions do  occur,  but the quantities are  so slight that  they
tend to evaporate on  the spot;   soapstone solution  is  neither dumped nor
 recirculated.   In processing  areas,  water is  not used  for washdown.   Dust
 is such a  Problem(due  to the  use of soapstone in dry  form)  that  any  attempt
to use water  for washdown merely complicates  the problem.

There  were no wastewater treatment  facilities operating at the plant
 at the time of the  visit.  The upgrading of air quality within the
 plant  has  completely  occupied  the attention of the engineering staff,
 thus  relegating concern for water effluent quality to a secondary
 pos i t i on.

                               \l\\-\k

-------
                                                                   DRAFT
     Synthetic Rubber Plants
          Plant J

Emulsion styrene-butadiene  (SBR) and acrylonitrile-butadiene  (NBR)  synthe-
tic rubbers are produced at this plant.  The annual  production  capacity  is
390,000 metric tons of SBR and approximately 10,000 metric  tons of  NBR.
The plant is located in an  industrial area with land available  for  expan-
sion.

Both SBR and NBR are produced by emulsion polymerization processes.   The
monomers are shipped into the complex from adjacent plants.  The SBR
crumb is produced  in non-extended, oi1-extended,  and carbon-black-extended
forms, while the NBR is produced  in non-extended  form only.  The crumb
rubber is used principally as tire rubber.  There are sixteen coagulation
and finishing  lines  in the plant.

The plant's intake water comes  from two sources.   River water is used for
cooling tower makeup, crumb rubber washing-slurrying, and area washdown.
Plant well water is  softened and  then used for solution preparation.   The
plant does not have  its own steam generating plant and purchases steam
from an adjacent facility.

The main process wastewaters are  generated at monomer recovery, crumb coag-
ulation, and rubber  washing operations.   Decant water from the monomer de-
cant system is recycled  in  part to the crumb slurrying operation.  The
remainder, containing styrene and  acrylonitrile,  is discharged to the pro-
cess sewer system  and has a significant COD.  The coagulation  liquor over-
flow  is a brine-sulfuric acid mixture, with a  low pH, high total dissolved
solids, and moderate COD.   The  crumb slurry overflow contains  COD, crumb
rubber particles as  suspended solids,  and oi1(when oil-extended forms are
produced).  The crumb-laden slurry overflow and  the overflow of coagulation
liquor pass through  crumb  settling pits where  the crumb separates and is
removed periodically by  a  scoop.  The  cleaning of the crumb pits results
in a  temporary upset as  the settled  crumb is disturbed  and re-suspended.
This  results  in poor effluent quality  from  the pits  for a  short period.

The  cleanup wastes from  the latex vacuum  and steam  stripping units are
another process wastewater  source.   This  wastewater  is  characteristically
high  in COD and  suspended  solids, and  contains uncoagulated  latex. ^The
units are cleaned  periodically  and  large  volumes of  water  are  used in this
operation.  The  resulting  wastewaters  are passed through settling  sumps,
where  rubber  solids  settle  out.

Clean-out wastewaters  from reactors  and  holding  tanks are  also produced
on an intermittent basis.   These wastewaters,  containing COD and suspended
solids, both  as  rubber  solids and as uncoagulated latex, are also  passed
through  settling  pits.   Spent caustic  soda  scrub solution  used to  remove
                              VII-15

-------
                                                                    DRAFT
inhibitor from butadiene prior to its polymerization,  is  bled  into  the
plant effluent;  this waste stream has high COD,  pH, alkalinity and
color, and contains some phenols.  Its flow rate,  however,  is  very  low.

The carbon black storage facilities, consisting of railroad unloading
equipment, a storage hopper, and slurrying equipment,  generates a waste-
water which is laden with fine carbon black particles.  This wastewater
is the result of the washdown and cleanup of carbon black spills and
air-borne fallout.  These wastewaters pass through two settling pits,
which operate in parallel.  When one pit is full  of carbon black waste-
water, the wastewater is allowed to settle and the second pit  is filled.
The settling pits achieve satisfactory clarification of the wastewater.

The utility wastewaters consist of cooling tower blowdown and  water soft-
ener regeneration wastes.   (There is no boiler blowdown,  since the  plant's
steam is purchased.)  One cooling tower has a very low blowdown  rate,
since a high proportion of the tower's makeup is steam condensete.   The
other cooling tower has a normal blowdown rate and generates wastewater
containing chromium, zinc, and other heavy metal  ions.

The plant's effluent treatment system consists of chemical coagulation
and primary settling, followed by an aeration lagoon and  a settling
lagoon.  The primary settling facility and the sludge  handling system
are shown in Figure VI1-1.  In the chemical coagulation process,  the pH
of the influent wastewater  is first adjusted using sulfuric acid  and
caustic soda.  Coagulation chemicals (alum and polyelectrolyte)  are added,
together with clay.  The latex and fine suspended solids  coagulate
around the clay, which causes the coagulated solids in the primary  clari-
ffer to sink.  The solids from the primary clarifier are thickened  and
pressure filtered, using a  lime slurry and filter aid.  The filter  cake
is hauled away by truck to a landfill.  The thickener  supernatant Is
returned to the head end of the plant, and the filtrate is discharged  to
the aeration lagoon.  The plant effluent quality is good:

               COD                               325 mg/L
               BOD                                25 mg/L
               SS                                 30 mg/L

The high residual COD concentration is typical of the high biological
resistance of the wastewater components.  The plant currently  is  conduct-
ing pilot studies to investigate the feasibility of using activated car-
bon to reduce the residual COD.  The results to date indicate  that  a final
effluent COD of 130 mg/L could be reached, but the company concluded that
the costs to implement this system would be prohibitive.
                           VII-16

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                                                           FIGURE VIM

PLANT J-. CHEMICAL COAGULATION AND CLARIFICATION PLUS SLUDGE HANDLING SYSTEM FOLLOWED BY  BIO-OXIDATION TREATMENT
EFFLUENT TO
At TREATMENT
7^
FINAL
EFFLUENT
tL ADCITION
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t
FINAL
EFFLUENT
OISCHARGE
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SETTLING
ZONE
SLOW
MIX

U
t
L
z
r.
\L
              pH CONTROL
                                                                       SLO» MIX SLUOGE
                                                                         CONDITIONING
                                                                                                                          15 PLATE
                                                                                                                      HIGH PRESSURE FILTER
 AIR
.CORE
 BLOf
                                                                                                                        FILTER CAKE TO
                                                                                                                        HOPPER FOR
                                                                                                                        FINAL DISPOSAL
           RAW
           INFLUENT

-------
                                                                    DRAFT
          Plant K

The plant complex consists of emulsion and solution styrene-butadiene
rubber (SBR) production facilities.  The annual  production  capacity of
emulsion SBR is 200,000 metric tons and of solution SBR is  130,000 metric
tons.  The complex is located in an industrial  area with virtually no
land available for further expansion.

The emulsion crumb rubber is produced in non-extended,  oil-extended, and
carbon-black-extended forms.  The emulsion rubber processing plant  is
arranged into essentially two parallel operations;  each operation con-
sists of a solution preparation building, a polymerization  area,  a coag-
ulation and finishing building, and a monomer recovery complex.   The
solution crumb rubber is produced also in non-extended, oil-extended and
carbon-black forms.  The solution rubber processing facilities  are simi-
larly divided into two parallel units;  each unit consists  of a  polymer-
ization area, a crumb slurrying and finishing building, and a solvent
and monomer recovery complex.  The solvent used is hexane.

The plant water supply is from on-site wells.  The boiler feed  water  is
subjected to hot lime softening and normal boiler feed treatment chemi-
cals.  The cooling tower makeup is treated with corrosion inhibitors,
anti-seal ing agents, and slimicides.  The process water used in emulsion
rubber production  is zeolite softened.  Untreated well water is used  for
slurrying, rinsing, and washdown.

The principal emulsion process wastewaters are the coagulation  liquor
overflow, the crumb rinse overflow, and the monomer recovery streams.   The
coagulation liquor is a sulfuric acid-brine mixture with a  low  pH,  high
total dissolved solids, and moderate  COD.  The crumb rinse overflow con-
tains floatable crumb rubber as suspended solids.   In addition, the slurry
overflows have high total dissolved solids and moderate COD.

The coagulation liquor and crumb slurry overflow  pass through settling
pits, where the rubber solids  separate.   Under normal operation, the
separator pits work well, but  they are not cleaned  frequently enough,  and
short-circuiting occurs.  Furthermore, during the cleanout operation the
pit  is disturbed,  and the once-separated  rubber escapes  into the effluent.
Some pits contain  an oil  layer because baler hydraulic  fluid or extender
oil  leaks onto the floor and  is washed down  into  the settling pit.

The wastewaters from the monomer recovery area are  characterized by high
COD and  suspended  solids.  These wastewaters originate  at monomer decant
systems  and cleanup operations, and contain  uncoagulated latex.  The waste-
waters from the periodic cleaning  of  the  monomer  recovery stripping columns
                           VII-18

-------
                                                                    DRAFT
contain hi gh concentrations of COD and of latex and rubber solids.   These
waters pass through  settling  sumps to separate the rubber solids and the
floating oils.  These  pits  are also cleaned out periodically.

The caustic scrub solution  is discharged to the final effluent when it
becomes saturated with inhibitor.  This wastewater is of very low flow
 (less than 1 gpm), but has  high COD, pH, alkalinity and color.  When the
latex storage and the  blend tanks are cleaned, the latex-laden rinse
water can be used for  latex blending if its solids content is greater
than 2 percent.  Tankage  rinse waters with rubber solids levels of less
than 2 percent are discharged to  the plant effluent.  The major contamin-
ant in this water is uncoagulated latex.

The carbon black slurrying  area is equipped with a settling pit which
receives spillages and washdown wastewaters.  The carbon black settles
out, and the  wastewater  overflows at a very  low flow rate into the final
effluent.  The settling pit is cleaned out periodically with a vacuum
truck.

The solution rubber  process wastewaters are very similar to those of other
solution rubber production  facilities.  The principal streams originate
at the crumb slurrying operation and the solvent-monomer recovery areas.
The crumb slurry overflow has moderate COD, suspended solids, and total
dissolved solids.  It  passes through a settling sump, where suspended
solids are removed.  The  wastewaters from the solvent and monomer recov-
ery areas are stripped condensates and decants, and are characterized by
moderate amounts of  COD and floating oils.

The utility wastewaters are boiler and cooling tower blowdown and water
treatment wastes.  The boiler blowdown has high total dissolved solids and
a high pH.  The cooling tower blowdown contains high total dissolved solids
and moderate levels of chromium and zinc from chemical inhibitors.  The
spent lime slurry from the hot lime water treatment system exhibits a high
pH and suspended solids level.  The lime slurry settles out in the plant
drain and must be mechanically removed at periodic intervals.  The waste
from the zeolite softener regeneration is a concentrated brine solution
with high total  dissolved solids.

The wastewater treatment  system consists of air  flotation clarification
and biological treatment (refer to Figure VI1-2).  The wastewater first
passes through a mechanical bar screen which removes large rubber solids,
and is neutralized to  pH  7.0 and dosed with coagulant and flocculant aids
in a rapid-mix tank.    The wastewater then.passes through a flocculator
tank and into the primary clarifier, where a slip-stream laden with air
is released near the bottom of the unit.  The rising air bubbles carry
the suspended solids and  oil-type contaminants to the surface, where they
                            VII-19

-------
                                                 FIGURE VII-2
     PLANT K: AIR FLOTATION AND BIO-OXIDATION  WASTEWATER  TREATMENT FACILITY
N>
O
                                                    FINAL EFFLUENT
   HAW
  WAJTEIATER
k

i

k
i


k
FEED TANK -
Qj
	 txj—
£*
                                                                       ALUM
                                                                       COAGULATION
                                                                       TANK
           CAT. POLYMER
           FEED TANK
                                                         ANIONIC POLYELECTROLTTE
                                                         KAKE-UP TANKS
                                                                                             AERATED LABOON
                FEED
                TANK
                                                                                                             O
                                                                                                             73
ALUM FEED TANK

-------
                                                                    DRAFT
are skimmed off.  The clarified effluent flows into an aerated  lagoon,
equipped with six aerators, where it is retained for 2k hours.

Effluent from the aerated lagoon is pumped to the secondary  air flota-
tion clarifier, where biological solids are removed.  Operations  include
rapid mix of coagulation chemicals, flocculation, and clarification.
The primary and secondary sludges are pumped to an on-site sludge  lagoon
for dewatering and drying.  Studies are being conducted to dispose  of
this sludge by off-site landfill or via incineration.  The treatment plant
produces a high-quality effluent.  Pollution parameters which are  still
present at substantial levels after treatment are total dissolved  solids
and COD.  The residual COD underlines the inherent biological resistivity
of some of the wastewater const!tutents.

          Plant L

This plant has SBR, polybutadiene, resin, and oil-additive production
facilities.   In addition, there  is a rubber compounding facility which
produces sheet rubber as a customer service.  The annual production
rates are:

     Cold-emulsion SBR                    120,000 metric tons
     Hot-emulsion SBR                      3,700 metric tons
     Solution-type polybutadiene          52,000 metric tons
     Solution SBR                         10,000 metric tons

The plant  is  located  in a  rural  area with land  available for expansion.
Emulsion rubber production stared  in 19^3, solution  type polybutadiene
in 1960, and  solution type SBR  in  1963.

The cold-emulsion type SBR  is produced  in non-extended, oil-extended,
and carbon-black-extended  forms.   It  is  used  primarily in tire manu-
facture.  This type of emulsion  SBR  is  similar  to  that produced at the
other plants  described  in  this  section.   The  process for  hot-emulsion
SBR  is  a higher-temperature  polymerization  and  is  non-extended; this
product  is used primarily  for electrical  wire covering.  The solution
type polybutadiene  is produced  as  non-extended  and  oil-extended rubbers
and  is  used primarily  in  tire manufacture;  toluene  is the solvent.
Solution SBR  is non-extended and has  several  end uses. The butadiene
used  in  the plant  is  received by pipeline from a neighboring plant,
and  the  styrene  is  shipped  in by tank  truck.

The  plant's water  supply  consists  of well water.  The plant does not have
steam generating  facilities  but purchases steam from an^adjacent plant.
The  well water  is  treated  with  corrosion inhibitors, slimicides, and dis-
persants  for  cooling  tower makeup  and  is softened to provide process water
for  preparation of  the  emulsion rubber solution.
                                  VII-21

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                                                                   DRAFT
The process wastewaters from emulsion rubber production originate
principally in two areas: crumb slurrying and monomer recovery oper-
ations.  These wastewaters are typical of emulsion rubber production
facilities.  The slurry overflow is passed through a crumb pit to
separate the crumb rubber fines.  The monomer strippers are cleaned
periodically.  The vacuum stripping vessels and steam stripping columns
are flooded with wash water, and the residual latex and rubber solids
are discharged with the wash water.  The units are finally rinsed,  pro-
ducing more wastewater with additional suspended solids.

Both of the solution type rubbers are produced by similar processes.
The main process wastewaters are the crumb slurry overflow and the
solvent-monomer recovery wastes.  The slurry overflow is passed through
a pit, where the crumb rubber is separated and periodically removed.
As is the case with all the plants visited, the crumb pits are not
cleaned regularly, and during cleaning the crumb is disturbed and
escapes the pit.  The wastewaters from the solvent-monomer recovery
area are condensates from monomer decant systems and solvent distil-
lation condensates.  They are characteristically high in COD, BOD, and
total dissolved solids.

The plant's utility wastewaters are cooling tower blowdown and zeolite
softener regeneration wastes.  The blowdown has high chromium and zinc
concentrations, from the corrosion inhibitor.  The softener regeneration
waste is a strong brine solution and therefore has a high total dis-
solved solids concentration.

The plant's wastewater treatment facilities consist of  settling ponds,
followed by aerated and stabilization lagoons.  The plant's final ef-
fluent is treated with alum and polyelectrolyte to obtain proper coagu-
lation of latex solids and fine rubber crumb particles.

The wastewater flows through two parallel sets of two settling ponds
each, where the settleable solids and oils separate.  The wastewater  then
flows through two further settling ponds in series.  The total detention
time in the six settling ponds is four days.  Troublesome oil is skimmed
from the ponds.  The wastewater then passes to a mechanically aerated
lagoon, which provides approximately three days of detention.  The
aerated lagoon effluent passes through two oxidation ponds, which
stabilize the wastewaters and settle the biological solids.  The total
detention time in the oxidation ponds is approximately  thirteen days.

Although overall treatment provided by the facilities is good, the
effluent quality (BOD particularly) does not meet the State requirements.
It has been established by analyses that the stabilization ponds are  not
producing the soluble BOD removals that were expected,  but the cause  of
                               VI1-22

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                                                                    DRAFT
the problem has not been determined.  There are indications  that  the
effectiveness of the ponds is dependent on the water temperature  (and,
therefore, the time of the year) but this hypothesis has yet to be
confi rmed.

          Plant H

The total plant complex consists of a butadiene plant and a  polybutadiene
production facility.  The butadiene plant started production in 1957  and
the polybutadiene facility in 1961.  The polybutadiene production facility,
which uses butadiene as a feed monomer, has a capacity of 85,000  metric
tons per year and is adjacent to the butadiene facility.  The complex is
located  in a rural area with good potential for expansion and land
acqu i s ition.

The polybutadiene is produced by a solution-type polymerization process
using butadiene as the feed monomer and hexane as the solvent. The crumb
polybutadiene rubber is used principally as a tire rubber.  In addition,
a high-grade variety is used as an  ingredient in the manufacture  of
impact-resistant plastic.  The rubber  is not oil- or carbon-black-extended.

The polybutadiene plant has two sources for water supply, well water
and river water.  The well water is used primarily for boiler and
cooling  tower makeup, while the river water (after clarification,
filtration, and softening) is used  in the crumb slurrying operation and
for general plant cleanup.

The principal process wastewaters originate in the solvent-monomers
reclaim  area and in the crumb slurrying operation.  The wastewaters
produced in the reclaim area originate from several operations:
solvent  recovery, monomer recovery, and feed drying.  The major
component of these wastewaters is produced by a decant system fed from
the solvent and monomer stripping operation.  This wastewater is
relatively clean, its only contamination being due to hexane at satura-
tion solubility.  The other wastewater streams from the reclaim area
have very low flow and are essentially innocuous with the exception of
dissolved hexane.

Impure recovered butadiene monomer  is  returned to the butadiene production
plant for purification.  Heavy slops (oily wastes) produced  in the hexane
recovery operation are sent to the  butadiene plant for disposal or are
used as  a waste fuel.  The other major process wastewater, the crumb
slurrying overflowiis laden with rubber crumb  in the form of suspended
solids.  The suspended solids are significantly reduced by  in-plant
screening and clarification in a pit.

At  least one finishing line recovers the solid rubber product directly
from the rubber cement.  No water rinse system is used.  The "finishing
                              VII-23

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                                                                    DRAFT
machine" takes cement and produces material ready for baling and
packaging.  This machine was not seen, and presumably is some type of
extruder for removing solvent.   It obviously has a potential for reducing
the effluent flow and leading attributable to the crumb rinse overflow.

There are two other process-associated wastewaters.   Spent  caustic  soda
solution, from scrubbing of butadiene inhibitor (to prevent premature
polymerization during storage and shipping), is batch discharged.  This
stream has extremely high COD, pH, alkalinity, and color, and contains
phenols.  The batch discharge is containerized in a pit and bled into
the plant effluent at a very low flow rate.  With such handling or
pre-treatment, it poses no wastewater problem.

The other wastewater which should be mentioned results from frequent
area washdowns.  This picks up primarily crumb rubber and oils.  The.
oils originate from leaks in baler hydraulic systems and leaks of pump
seal oil.  In solution-type polymerization, water must be eliminated
from much of the process equipment.  Oil is used to seal and lubricate
the process pumps.  The washdown wastewaters contribute the major
proportions of suspended solids, soluble organics, and oils in the final
effluent.

The principal non-process wastewaters are boiler and cooling tower
blowdowns and water treatment wastes.  The wastewater characteristics
of these streams are high total  dissolved solids, and moderate COD,
suspended solids, and pH.  The cooling tower makeup is treated with a
corrosion inhibitor containing chromium and zinc.  These metals appear
in the cool ing tower blowdowns.

The total effluent from the butadiene and polybutadiene plants passes
through an oil  separator and straw filter before discharge.  Since the
quantity and loading of the wastewaters from the butadiene plant are
far greater than those from the polybutadiene plant, no meaningful
treatment data could be obtained.  The raw wastewater flow and loading
of the polybutadiene plant were the lowest of any of the synthetic
rubber plants visited.

It is planned to expand the synthetic rubber plant production facilities
shortly.  This  expansion will approximately double the existing synthetic
rubber production capacity.

          Plant N

The plant complex consists of isoprene, polyolefin resin, polyisoprene,
and polybutadiene production facilities.  The complex was completed in
1962.  The polyisoprene production capacity is 65,000 metric tons per
year and the annual  production of polybutadiene is 110,000 metric tons.
The complex is  located in a rural area with expansion capability and
undeveloped land of its own.
                                 VI1-

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                                                                    DRAFT
The polyisoprene is produced by solution polymerization with hexane as
the solvent, using isoprene from the neighboring isoprene plant  as  feed
monomer.  Several types of polyisoprene are produced in this facility.
Each type requires a separate production run on common processing
equipment.  The crumb rubber is used mainly for tire manufacture and is
not oil or carbon black extended.

There are two polybutadiene lines which employ slightly different
processing techniques.  There is no significant difference in the over-
all wastewater flows and loadings from these two processes.  The
polybutadiene is consumed principally in tire manufacture, and
approximately 50 percent of the polybutadiene is oil extended.

The plant's water supply is river water.  Process and boiler makeup
water receives extensive treatment, consisting of coagulation, clari-
fication, filtration, chlorination, and softening.

The main process wastewaters are produced in the monomer-solvent reclaim
area and the crumb slurry ing operation.  The wastewaters generated  in
the reclaim area have low flow rates and, with the exception of  saturatin
with solvent or monomers, are relatively clean.

Part of the recovered isoprene is sent in a slip stream to the isoprene
production plant for purification.  This procedure serves to blow down
the accumulated impurities.  Impure butadiene recovered from the poly-
butadiene plant is hauled from the plant as a waste.  The crumb slurrying
overflows are passed through settling pits where the crumb is trapped
and periodically removed.  Surfactants are added to the crumb-water
mix during the coagulation operation to prevent the crumb from
agglomerating into masses which are too large.  These surfactants enter
the crumb slurry overflow.

One type of polyisoprene produces a crumb slurry effluent which has a
considerably higher dissolved organic loading than the other polyisoprenes
or the polybutadiene types.  This difference is inherent  in the chemistry
of the process and is not a general or widespread problem  in the
synthetic rubber industry.

Area wash-down and cleanup is a major contributor of contaminants to
the final effluent.  Crumb screens used inside the processing areas
are hosed down to remove coagulated rubber.  The resulting wastewater
has high suspended solids levels and is passed through the crumb
settling pits.  Spent caustic solution from the inhibitor removal system
is containerized and bled into the final effluent.  It has the typical
high, COD, pH, alkalinity, and color.
                                VII-25

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                                                                    DRAFT
Typical  utility wastewaters, principally boiler and cooling tower
blowdowns and water treatment wastes, are generated at this plant.
Characteristics of these wastes are high total  dissolved solids, with
moderate COD, suspended solids, and pH.  The cooling tower makeup  is
treated  with a low chromium corrosion inhibitor.  This produces chromium
levels in the cooling tower blowdown that are less than one quarter of
those associated with conventional cooling tower corrosion treatments.

The wastewater treatment system consists of an equalization basin
(four-day detention), a neutralization sump, with nutrient addition,
followed by an activated sludge plant (refer to Figure VI1-3).  The
waste activated sludge is first thickened and then pumped to a sludge
drying basin on the plant property.  The treatment plant gives very
good BOD effluent levels (10 mg/L), however, the effluent COD level  is
considerable (250 mg/L).  This 5s due to the biological stability  of
many of  the wastewater components such as the monomers and solvents,
which, although generally considered insoluble, do have some solubility
in water.

An apparent characteristic of the plant's wastewater which can be
attributed to the synthetic rubber production  is foaming  in the
aeration basins and  in the final outfall.  This  is apparently caused
by excessive use of  surfactants by the production  personnel in the
crumb rinse operation.  Another problem  is poor settling  of the
biological sludge in the secondary clarifier.   Efforts were made to
assist settling, and achieve additional  COD  removal,  by  adding activated
carbon granules to the aeration basins upon  which  biological  solids
could nucleate.  This did not produce  satisfactory  results.  The current
technique which is proving more successful  is  the  addition of  coagulation
aids to the clarifier  influent.  This, however,  is  proving to  be
expensive on an annual-cost basis.   A  less frequent  problem,  but more
serious,  is an apparent high BOD  slug  loading,  with  associated toxicity,
that unpredictably occurs  in the  plant  influent.   This  problem is
uncontrolled at present, but appears to  originate  with  the production
of either the polyolefin resin or  one  type of  polyisoprene.

          Plant 0

The plant complex consists  of  polybutadiene, polyisoprene and ethylene-
propylene diene terpolymer  (EPDM)  rubber production facilities.  The
commissioning of all  the production  facilities occurred between 196?
and  1970.  The annual  production  capacities  are:   polybutadiene 56,000
metric  tons, polyisoprene  50,000  metric tons,  and EPDM 25,000 metric tons,
The plant  is  located in  a  rural  area and has considerable land for
expansion.
                                  VI1-26

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                                              FIGURE VII-3
             PLANT  N:  ACTIVATED SLUDGE WASTEWATER  TREATMENT  FACILITY
RAN INFLUENT
       WASTE SLUDGE
       TANK
RAW SANITARY
WASTEWATER
                                                EQUALIZATION
                                                BASIN
                                                  TOWBRO CLARIFIER
                         AERATION BASINS
                        RETURN  SLUDGE
                                                     CHLORINATOR
SANITARY WASTE
SECONDARY TREATMENT
                                                  EFFLUENT
                                                  KON! TORINO
                                                  STATION
                                                                                                       NUTRIENTS
                                                                 NEUTRAL-
                                                                 IZATION
                                                                 BASIN
                                                                                                                 •ACID
                                                                                                                 •ALKALI
FINAL
EFFLUENT

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                                                                    DRAFT
Each of the three synthetic rubber products has its  own production
facility and is produced in a solution polymerization process.   Poly-
butadiene rubber is carbon black extended.  The principal  end-use of the
crumb rubbers is in tire manufacture.

The plant's water supply is well water.  Well water  is treated  with
corrosion inhibitors and slimicides for use as cooling tower makeup,
and softened for use as boiler quality water.

Principal process wastewaters originate in the crumb slurrying  overflow
and presumably in the solvent, monomer, and reclaim areas.  Carbon
black added at the coagulation-slurry ing stage is essentially trapped
in the crumb rubber matrix.  Carbon black spills and leaks pass through
a settling sump and are allowed to overflow  into the final effluent.
The settled carbon black is removed by vacuum truck.

Extender oil that  is not entrained in the rubber crumb can contaminate
the slurry overflow wastewater.   It is understood that screens, with
higher crumb removals than conventional equipment, have been installed
in this plant.  The butadiene monomer  is  inhibited and presumably there
is an associated spent caustic  scrub solution  discharge.  Area washdown
and cleanup  is on  a shift-by-shift basis.  Whenever  possible, the
material  is cleaned up  in  such  a  manner to eliminate wastes from the
wastewater system.

The plant's utility wastewaters are characterized by high  levels of
total dissolved  solids  and moderate pH.   The cooling tower  blowdown
has high  chromium  and zinc content originating from  the cooling tower
corrosion  inhibitors used.

The plant's wastewaters are  first passed  through  skimming  and  settling
basins where the rubber crumb  is  trapped.  The waste crumb  rubber is
removed every  two  to three months by  dip  bucket.  The  effluent  from
these pits flows into two  12,000  sq.  meter  (3-acre)  lagoons.  The
process  effluent from the  lagoons combines with  treated sanitary, storm,
and utility  wastewaters before  entering  first a  60,000 sq.  meter  (15-acre)
 lagoon  and finally a  120,000 sq.  meter (30-acre)  lagoon before  discharge
to  the  receiving waters.   The  final wastewater quality is good.  COD,  BOD,
and  suspended  solids  are  at  an  approximate level  of  50, 5,  and  10 mg/L,
 respectively.   This plant, however,  is particularly  fortunate  in having
considerable land  for  use  as wastewater  lagoons.   It is  not possible^
for  all  synthetic  plants  to have  the  same or even comparable facilities.

           Plant P

This  plant produces styrene-butadiene (SBR)  and aerylonitrile-butadiene
 (NBR)  latexes.  In addition, the plant produces polyvinyl acetate
 emulsions and  hot  melt  adhesives.  The annual production rates of  the
 latexes are:   styrene-butadiene latex  18,000 metric tons, acrylo-
                                   VI1-28

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                                                                   DRAFT
nitrile-butadiene latex  3,000 metric tons.  The plant is located  in  a
rural area with land available for expansion.

The butadiene latexes manufactured at the plant are made similarly
utilizing equipment trains of a similar nature.  The monomers are
shipped into the plant by both tank car and tank truck.  The latexes
produced are used for carpet backing, dipped goods, and adhesives.

The plant's water comes from on-site wells.  The water is treated  in
a dual-bed demineralizer to supply boiler quality makeup water and
process water for solution preparation.  The cooling tower water
is treated with a corrosion inhibitor and algicide.

The principal process wastewaters produced  in the plant are generated by
equipment cleanout, area washdown, and stripper condensates.  Tank cars
and tank trucks are rinsed with water and the contaminated water  is
discharged to the wastewater treatment facility.  These wastewaters will
contain monomers and uncoagulated latex.  Reactors and strippers are
cleaned of solid deposits with a high pressure watergun and then water
rinsed.  Blowdown tanks, filters, compound  tanks, and  storage tanks
are rinsed with water.   In all cases the wastewaters  discharged to the
wastewater treatment facility  contain organic  compounds and  latex.
Latex spills and leakages are  first coagulated with alum, cleaned up
in-place, and finally washed down.  The washings are  sent to the  treatment
faci1i ty.

Excess monomers are stripped from the  latex with steam under vacuum.
The vacuum is produced  using steam jets and not vacuum pumps.  The
excess styrene, or  aerylonitrile,  is condensed  and  discharged to  a
receiver.  Although the  receiver  is  periodically decanted and the con-
densed styrene or acrylonitrile drummed for disposal,  styrene and
acrylonitrile still enter the  effluent wastewaters.   A caustic  scrub
solution  is  used to remove the butadiene  inhibitor, which  is bled
gradually to the final  effluent.  Characteristics  of  this stream  are
high COD, pH, alkalinity, and  color.

The  plant utility wastewaters  enter  the  storm  sewer system.  The  boiler
blowdown  has a  low  flow rate  but  high  total dissolved solids.   Demineral-
 Jzer  regeneration wastes are  both  acidic  and alkaline and may potentially
produce  pH peaks.   The  cooling tower blowdown  is  high in total  dissolved
solids but,  because the corrosion  inhibitors used  are chromium  and
zinc free, these heavy  metals  do  not appear in the blowdown.  The vacuum
pump  seal water  is  currently  discharged  on a once-through  basis to the
storm sewer  system. This water picks  up  small quantities  of organic
compounds but  has  only  a moderate COD  concentration.   Studies  are being
made to  recycle  the bulk of  the seal water and discharge the blowdown
only to  the  treatment  facility.
                                  VI1-29

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                                                                    DRAFT
The plant's treatment facility consists of chemical coagulation and
clarification followed by activated sludge secondary treatment.  The
final effluent after secondary treatment is discharged to a municipal
treatment plant.  All the latex plant process wastewaters are discharged
to two coagulation pits.  They operate so that one pit is being filled
with wastewater, while water in the second pit is being treated, settled,
and emptied.  The pH of the wastewater is first adjusted with  lime
and then treated with ferrous sulphate, a polyelectrolyte, and limestone.
The latex solids coagulate around the  limestone which serves to sink
the solids.  The settled solids are removed from the pits periodically
when the solids depth becomes excessive.  The clarified wastewater enters
four aeration basins operated in parallel.  The basins are equipped with
four 15-horsepower aerators.  The aeration basin effluent enters a
secondary clarifler and overflows to a sump from which it  is pumped
to the city treatment plant.  The clarifier underflow is sent  to^a
sludge thickener, while the supernatant  is returned to the aeration
basins.  The biological sludge  in the  thickener  Is periodically removed
and  landfilled.  The coagulation pit solids and  the thickened  biological
solids are not  suitable for satisfactory  landfill  because of their high
water content.  Studies are currently  underway to  determine adequate^
techniques for  dewatering and disposing  these sludges.  The coagulation
pits provide good quality primary effluent.  The COD  and BOD of this
effluent are high, however.  The secondary treatment  plant produces a
final effluent  having a COD and BOD of approximately  600 and 50 mg/L
respectively.   The high COD:BOD ratio  indicates  high  biological  resistance
of the wastewater constituents  from  this  latex plant.  Although  the BOD
level  (50 mg/L) would not be  suitable  for  direct discharge,  it is  very
amenable to acceptable  discharge to  secondary treatment  plants.

          Plant Q.

This plant  is  responsible for  the manufacture of styrene-butadiene
 latexes.  The  annual  production rate  is  approximately 21,000 metric
tons.  The  plant commenced  production  in 1952  and  is  located  in an
urban  area  with limited room  for expansion.   The plant  also  has a
 research facility and a pilot  plant.

The  styrene-butadiene family  of latexes produced at the plant  can be
classified  by  three  groups:   styrene-butadiene  latex, styrene-butadiene
 carboxylated  latex,  and styrene-butadiene-vinyl  pyridine latex.  All
 these  latexes  are produced  by similar  processing techniques  and equip-
 ment.   The monomers  used (styrene,  butadiene, organic acids,  and vinyl
 pyridine)  are  shipped to the  plant  by  tank car and tank truck.  The
 latexes  produced  are used for tire fabric coating, backing material,
 and paper  coatings.
                                   VI1-30

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                                                                    DRAFT
The plant uses city water for process water, boiler makeup water,  and
cooling tower makeup.  The boiler makeup is softened before injection.
The cooling tower makeup is treated with a dispersant, corrosion inhibitor,
and slimicide.  The process water, used for solution preparation,  is
deionized before use.

The principal process wastewaters generated in the plant originate from
equipment cleanout, area washdown, and stripper condensates.   Excess
monomers are not recovered.  Reactors, strippers and storage  tanks are
periodically cleaned of rubber build-up by hand and then rinsed with
water.  Generally, large quantities of water are used for each cleanout.
The latex filters are frequently cleaned.  This involves first removing
the trapped rubber solids and flushing the filter with water.  The
rinse waters contain suspended solids, COD, and uncoagulated  latex.
Floors and loading-unloading areas are flushed with water. These waste-
waters contain COD, suspended solids, and uncoagulated latex.  The
vapors from steam stripping operations are condensed and discharge into
a receiver.  The receiver waters which overflow to the plant  sewers
have a high organic loading with correspondingly high COD and oil
levels.  The seal water for the vacuum pump serving the vacuum stripping
equipment is slightly contaminated with organics, and presently discharges
on a once-through basis.  Studies are being made to collect  individual
seal water discharges and recycle the bulk of them with a controlled
blowdown of contaminated water.  This will reduce the total volume in
the plant's final effluent.

The regeneration waste from the boiler water makeup softener is a
concentrated salt solution and therefore contributes high total dissolved
solids to the effluent.  The process water deionizer  is regenerated with
sulphuric acid and caustic soda.  The discharge of these solutions will
produce both acid and alkali peaks  in the effluent, although there is
generally an excess of sulphuric acid in the daily regeneration discharges.
The boiler and cooling tower blowdowns contribute high total  dissolved
solids and moderate COD to the plant's final effluent.

The treatment of the plant's wastewaters includes equalization, chemical
coagulation and settling, and secondary treatment  in the  local munici-
pality's treatment plant.  The wastewaters are first pumped  from the
plant effluent trench into an equalization basin, which provides
approximately 2k hours detention and  is aerated with two aerators.  The
pH of the equalized wastewater is adjusted from normally alkaline by
addition of sulfuric acid to the neutralization sump.  The wastewaters
are pumped from the sump to a reactor-clarifier where alum,  coagulant,
and polyelectrolyte are added in the mixing chamber.  The  latex and
fine rubber particles are coagulated and collected as a sludge from the
bottom of the clarifier.  The clarified effluent overflows the clarifier
to the city's sanitary sewer for secondary treatment.  The clarified
sludge is sent to a thickener .and finally to a sludge holding tank, and
is then loaded into a tank truck for disposal.  The supernatant from
the thickener is returned to the reactor-clarifier.  The treatment
                                  VI1-31

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                                                                    DRAFT
system described above produces a good quality primary effluent.   COD
and BOD are reduced by approximately 70 and 50 percent, respectively.
The suspended solids and oil are decreased by 80 and 50 percent each.

Summary of Control  and Treatment Technology

In-plant control technology covers segregation and measures for handling,
reuse, modification of processing, and disposal of various types of
wastewaters,  including spills and leakage, washdowns, control  of runoffs,
and housekeeping practices.  End-of-pipe treatment technology covers
the treatment of various combinations of process and non-process waste-
waters.  Separate discussions are presented for the Tire and Inner Tube
and the Synthetic Rubber segments of the industry.

     Tires and Inner Tubes
          In-Plant Control

In-plant measures included  the proper handling of soapstone, of the
latex dip,  and of discharges from air pollution equipment.

               Soapstone

Soapstone is a slurry normally consisting of clay, an emulsifying agent,
and water.   According to one plant representative, soapstone, if
continually discharged,  will contribute a high solids and BOD loading
to the process wastewaters.  The standard method of eliminating a continuous
discharge of large quantities of soapstone is the use of a closed-loop
recirculation system.  Such a system needs periodic cleaning, usually
on a weekly basis.  This cleaning operation can, but does not necessarily,
lead to a discharge.  Prior to cleaning, the soapstone solution in the
system is generally transferred to storage tanks.  The alternative to
recirculation is to discharge the solution directly into the process
sewers.  Both practices  were observed during the field survey, the first
being the better from a  wastewater control standpoint.  Soapstone wash-
water is potential discharge which is commonly sent to end-of-pipe
treatment.   However, it  was observed that this washwater could be stored
and used as makeup for the  soapstone solutions for future operations.
Alternative methods for  controlling discharges from weekly washdown
include the use of substitute solutions which require the system to be
cleaned on  a less frequent  basis.

Control of  minor discharges of soapstone, such as spills and leakage,
Is achieved by the use of curbing and by blocking off drains in the
dipping area.  In addition, drip pans are provided for stock during
the air-drying operation.  Soapstone that is spilled into the curbed
                                  VI1-32

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                                                                    DRAFT
area  is periodically vacuumed out and sent to a landfill  site.   Newer
plants are constructed without drains in this area, thus  eliminating
the possibility of soapstone contamination of process wastewaters.
Instead of curbing, steel grates are placed on the floor; these can be
removed when cleaning the area.

               Latex Dip

The most common practice of the  larger manufacturers is to eliminate
this operation from the tire facility.  Fabric is dipped  by a centrally
located facility and then shipped to the tire plant.  However,  in
plants that still dip fabric, the accepted procedure is to seal off
drains in the immediate area, supply the area with curbing, and drum
the waste solutions for disposal at landfill sites.  The  alternative  is
to dump the waste solutions into process sewers which are destined  for
end-of-pipe treatment systems.  The amount of waste from  this operation
is small, less than 230 liters (60 gals) per day.  Drumming of  the
solution is therefore preferred, since treatment of this  stream once
diluted with other streams  is difficult.

               Air Pollution Control Residues

It is not common for manufacturers to use  large quantities of wet
particulate-collection systems.  In the compounding area,  in particular,
bag-houses, rather than wet scrubbers are  used.  Wet systems are more
common in the tire-finishing area, where they collect the grindings from
the white sidewall grinding machines, balancing machines, and the
tire-repair area.

Discharges from wet scrubbers contain high  loadings of settleable
solids, which must be removed before final discharge.  The solids
collected from the tire-finishing area can be settled out  in a small
sump.  The particulates are large, and with a properly designed separator,
the clarified water can be, and  frequently  is  completely reused.

The discharges from wet scrubbers used in  the compounding area are much
finer and require longer settling times.   Only one plant  visited used
wet scrubbers in this area.  This plant used a 2,100 sq.  meter (0.52-acre)
lagoon to separate the solids from this discharge.  Unless specifically
required to meet air pollution ordinances, wet scrubbers in this area
are not recommended.

Additional air pollution equipment can be  found  in the tire-painting
areas.  Stricter air emission standards and OSHA standards are forcing
tighter control Is on particulate and solvent emissions from this area.
Consequently, the industry  is currently attempting to substitute water-
                                  VI1-33

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                                                                    DRAFT
based paints and sprays for solvent-based materials, but with only
limited success.  Wet air pollution equipment in this area was found
at only one plant; there was no wastewater discharge, because all the
scrubber water was reused.

               Spills and Leakage

To control  oily wastewaters resulting from spills and leakage,  the common
practice is to provide curbing and oil sumps and to seal drains.  In
older plants, the roller mills are located in basins.  The blocking off
of drains in these basins as a control measure is not feasible because
electrical  machinery is located in the basins.  A broken water pipe
would fill  the basin, thus shorting out the machinery.  Curbing is used
to keep normal area washdown and periodic leakages and spills from
entering the basin and thus contaminating process waters.  In newer
plants, machinery is located on the floor surface.  Updated seal designs
prevent the leakage of oil.  In many cases, potentially contaminating
areas have  no drains, thus eliminating the possibility of oil in these
process wastewaters.

In plants where recirculated water is the primary source for cooling,
the process and non-process sewers are separate.  Oil sumps and API
separators  can therefore be provided to treat oily process wastewaters.
The separable oil from these devices is removed either periodically by
maintenance people or continuously by a belt filter:  the continuous
removal is  considered the better practice.  During periodic removal of
oil, the agitation supplied will result in a large quantity of oil
being released to the effluent,thus reducing the separator's overall
average removal efficiency.

In plants where the primary source of cooling is once-through water,
process and non-process sewers are combined.  Removal of oil must be
accomplished in an end-of-pipe treatment facility.  Dilution by non-
process wastewaters directly affects the removal efficiencies of oil
in the end-of-pipe treatment facility.

               Washdowns and Machine Cleaning

Common practice for prevention of process-area washdowns from contaminat-
ing wastewaters is the use of dry sweeping equipment.  These include
automatic sweepers, brooms, and shovels.  Oily spills are cleaned using
solvents and rags, the resulting contaminated material being drummed
and sent to a landfill.  Practices employed in non-process areas (such
as the boiler house and storage areas) are similar.

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                                                                    DRAFT
Machines and machinery parts are normally cleaned with solvents  or
steam.  Spent solvents are drummed and sent to a landfill.   The  use
of steam requires a special area supplied with curbing and  an API
separator to remove separable oil and solids.   Discharges  of un-
treated oil- and solid-contaminated steam condensate occur  and con-
stitute a significant source of process wastewaters.  Although steam
cleaning has the disadvantage of having a continued discharge that
must be treated, it eliminates the possibility of a careless operator
discharging large quantities of organic solvents into an untreated
process wastewater stream.

Molds from the curing presses are normally cleaned by sand- or air-
blasting equipment.  Tnese are dry, and involve no wastewater problem.

               Runoff

Runoff from oil-storage areas occurs due to oil spills, storm water,
and various blowdowns which occur in the storage area.  Handling
practices vary within the  industry.  Minimal control involves the
diking of all oil-storage  areas to prevent contamination of waste-
water by large oil spillages which can occur during unloading or due
to leaking tanks.  These dikes generally are provided with drainage
ports to prevent normal storm water from filling the diked area.
This allows minor oil spills, attributable to operator negligence,
to contaminate storm runoff.  A better system involves the diking
of the storage area, the roofing of storage area to prevent storm
runoff contamination, and  use of an oil sump to collect minor spills
and leakage.  Collected oil  is drummed and sent to a landfill.  To
prevent oil from unloading areas from contaminating the wastewaters,
drains are diked and covered with straw filters.  This control tech-
nique suffers from the possibility of storm runoff contamination.

Other treatment schemes include the use of separators to treat oil
storage runoff.  The primary emphasis here is to treat runoffs due
to continual water running through the area.  The systems generally
are not designed to handle increased  loads due to storm runoff.

Solvent storage and maintenance areas are normally confined to build-
Ings.  To decrease the possibility of contamination due to operator
or maintenance negligence, these areas are not supplied with drains.

          End-of-Pipe Treatment

End-of-pipe treatment  in this segment of the  industry generally in-
volves the treatment of combined process and non-process wastewater
in a primary sedimentation basin or  lagoon.  Once-through, non-contact
cooling water usually  is not treated  even though the possibility exists
for oil contamination  from process wastewater.  Primary emphasis is on
removal of separable solids  from the  non-process boiler blowdowns and
                                   VI 1-35

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                                                                    DRAFT
water treatment wastes and from the process washdown waters (if any)
from the soapstone area.

The most effective system, although not generally applicable because
of land requirements, is the use of judicious water management tech-
niques to minimize non-process discharges and of holding lagoons to
contain all  wastes including process, non-process, and storm runoff.
Other lagooning systems used for treatment of all process (including
once-through cooling water) and non-process wastewaters were observed.
Residence times varied from twelve to twenty-four hours with surface
loadings as  high as 12,000 15ters/min/sq meter (1,200 gal/min/sq ft).
Auxiliary equipment observed included oil skimmers and sludge handling
equipment.

From the standpoint of treating process wastewaters, these systems
suffer heavily from dilution,  particularly in the treatment of grease
or oily wastes.  Dilution by process streams was as high as 75 to 1.
Dilution by  heavy storm runoff was an additional problem at many
locat ions.

     Synthetic Rubber

          In-plant Control

Since the synthetic rubber industry is highly technological, involving
many proprietary and confidential processing techniques, many potential
in-plant wastewater control methods would call for radical changes in
processing or product quality.  Such techniques are obviously not
feasible.  However, some potential control methods deserve mention so
that the!r applicabi1ity may be evaluated.

               Crumb Rinse Overflow

It was observed that some crumb rubber plants generate crumb rinse
overflows which have a lower loading of rubber fines than other plants.
Generally, however, such losses cannot be reduced with finer in-plant
screens since they are a function of both the type and the coagulation
properties of the rubber.  One plant did use a proprietary method to
finish the rubber cement in which a water slurry is not used.  This
system eliminates the crumb slurry overflow and the contained rubber
fines.  It is not necessarily applicable wholesale to crumb rubber
production,  but does merit investigation by industry.

               Coagulation Liquor Overflow

Most emulsion crumb rubber processes use an acid and brine coagulation
liquor.    One plant, however,  coagulates the latex with an acid-
polyamine liquor which reduces- the quantity of total dissolved solids
discharged in the coagulation liquor overflow.  The use of this type
                                   VII-36

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                                                                DRAFT
of coagulation liquor is not always possible, but if employer could  sig-
nificantly  reduce the total dissolved solids  in the final effluent.

              Vacuum Sys terns

Several  plants are converting  vacuum systems  from steam jet ejectors to
vacuum pumps  for efficiency and wastewater reasons.  In order to maximize
the wastewater benefits derived from the use  of vacuum pumps, the seal
water should  be recycled. An  overflow is generally required from the
seal water  recycle system; this overflow is normally slightly contaminated
with oil but  has a better quality  than the steam jet condensate.

              Caustic Scrubbers

 In  some plants, the  caustic  soda  solution used  to  remove inhibitors from
some monomers (notably butadiene)  is  replaced batchwise.  The spent
caustic soda  solution, usually 10-20% sodium hydroxide, should  not  be
discharged batchwise.   It should  be containerized  and  bled into the total
plant effluent, thereby diluting  its  high pH, alkalinity, COD,  and  color
contribut ions.

               Carbon  Black Slurries

The usual method  is  to slurry the carbon black for addition to the  rubber
 with water.  One  plant visited employs  a steam grinding-slurrying tecn-
 nique which reduces  carbon black spillage and consequently washdown and
 Runoff  wastewaters laden  with black fines; this technique avoids the need
 for carbon black settling pits and the  associated pit cleaning costs.

               Latex Spi11s

 Latex spills and leakages occur from time to time  in all  emulsion crumb
 and^atei  plants.   In most cases,  the spill  is washed to the nearest
 plant driin  using a water hose.   In many cases, this produces  unnecessary
 washdown water and dilutes the latex so that subsequent treatment  by
 coagulation  is much more difficult.  An alternative techn.que  ,s to
 coaqu ate  the latex in situ with  alum, for example, and remove the
 coaguated rubber solids with scrapers.  The volume of subsequent  wash-
 £2 water required is less and  the  latex solids  in the washdown water
 are greatly  reduced.

               Baler Oi 1



 -^££si«!SS S1~-
         *- ««""»  "    _ =   .      	  r u_i_r 0:i  ipakc; and can
                                VI1-37

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                                                                    DRAFT
installed to keep leaked oil from leaving the baler area.   Balers  using
water as the hydraulic fluid are also available and are being used in
some plants; oil  leakage with this type of machine is obviously elimi-
nated.

          End-of-Pipe Treatment

               Emulsion Crumb Plants - Primary

It is normal practice for crumb rubber producers to recycle part of the
crumb rinse water.   The remainder of the crumb rinse water is discharged
in order to blow down accumulating fine rubber solids and dissolved
solids and organics.  The rinse water discharge or overflow is clarified
before final treatment in a crumb separation pit.  The trapped rubber
solids are removed  periodically by scoop.  A very common shortcoming of
these separators is that they are operated as single units and are not
cleaned frequently  enough.  This results in short-circuiting followed
by poor separation.  In addition, when the pits are cleaned, the sepa-
rated rubber solids are disturbed and rubber solids that had previously
separated recombine with the pit effluent until the condition of the pit
stabilizes.  Dual pits would solve this problem:  one pit would stay in
operation while the other was cleaned and allowed to stabilize.

Since wastewaters from emulsion crumb plants contain considerable quan-
tities of latex, it is necessary to coagulate the  latex in order to
achieve a good quality effluent.  Chemical coagulation by  itself  is
seldom sufficient,  because the density of the coagulated rubber is
normally close to that of water.  Therefore, it  is customary to add
a "sinker"  (clay or limestone) to the coagulation mixture  to sink the
coagulated  rubber and effect the separation.  For a small  wastewater
flow, chemical coagulation using (for example) alum, polyelectrolyte,
and clay in a rapid mix tank can be followed by  flocculation  in a
flocculator tank.  Clarification can then be accomplished  in a  rectan-
gular clarifier equipped with solids removal equipment.  Larger
wastewater  flows can be treated  in a reactor-clarifier with  rim
overflow and central sludge draw-off.

The collected sludge can be thickened and dewatered before disposal
in a  landfill.  Dewatering  studies on this type  of  sludge  concluded
that a plate-and-frame pressure  filter performed well.  The  installed
filter was  automatically controlled for  feed shut-off, silter  opening,
core blowout, filter closing, precoating, and feed  restoration  (refer
to Plant J).

One plant (Plant K) uses chemical coagulation followed by  air  flotation
for primary clarification  (6).   Instead  of sinking,  the  rubber solids
are floated to the clarifier surface with air bubbles  and  removed by
surface solids removal equipment.  This  treatment  facility is  rela-
tively new  and has had start-up  troubles, although  they  have been
satisfactorily resolved.   Air flotation  in this  application  produces
primary effluent of good quality.


                                    VI1-38

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                                                                    DRAFT
The collected surface solids are pumped to a sludge impoundment  lagoon
where they dry out.  The use of this lagoon is limited and a long-term
solids dewatering and disposal technique will have to be found.

Where adequate land is available, rubber solids separation has been
achieved using primary settling ponds.  Chemical coagulation of  the
solids prior to discharge to the ponds is usually necessary.  The
settled and floating solids (since both types are produced) are  re-
moved from the ponds periodically by vacuum truck or scoop.

               Emulsion Crumb Plants - Secondary

Biological oxidation of the primary effluent is achieved in aerated
lagoons or in activated sludge plants.  Generally, a nutrient must be
added.  Both technologies obtain satisfactory oxidation of the dis-
solved contaminants; problems can arise in the clarification of  the
secondary effluent.  Good secondary clarification of effluent from an
aerated lagoon has been obtained with the aforementioned air flotation
plant, which is a dual system with both primary and secondary air flota-
tion clarifiers.

If sufficient land is available, the effluent from the aerated lagoons
can be clarified and stabilized in stabilization ponds.  This type of
facility is temperature dependent, of course, and performs better in
warmer climates.

Clarifiers are commonly used for secondary clarification in activated
sludge plants.   They are generally adequate, but cases exist where
high solids carryover is a problem.  Secondary clarification can be
assisted with coagulation chemicals in much the same manner as for
primary clarification, but the additional chemical cost is high.

One plant in the industry, in an area where water  is in short supply,
is evaluating evaporation to remove  wastewater contaminants (7).
Problems encountered have included severe scaling problems and high
operating costs.  The scaling problems stem from the fact that the
scale-producing characteristics of the wastewater vary greatly on a
day-to-day basis, and are greatly affected by the  inherent opera-
tional variations  in the rubber plant.

               Emulsion Crumb Plants - Advanced

After secondary treatment, emulsion crumb wastewaters  still contain
high  levels of COD.  A high COD  level appears to be a  common charac-
teristic of secondary effluents from emulsion crumb, solution crumb,
and latex plants, and appears to indicate that certain constituents
of the wastewaters generated  in synthetic rubber plants are refractory
to biological oxidation.
                                    VI 1-39

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                                                                    DRAFT
               Solution Crumb Plants - Primary

Primary clarification of the solution crumb plant wastewater  is  carried
out in crumb pits.  These pits are similar in design to thoss for  emul-
sion crumb production facilities.  To avoid re-suspending the separated
rubber solids, dual crumb pits should be used.

Other forms of primary treatment are not required for solution crumb
wastewaters, since uncoagulated latex is not present and the  fine
rubber solids separate readily.

               Solution Crumb Plants - Secondary

Secondary treatment technology uses both activated sludge and aerated
lagoon  systems.  Good BOD removals are achieved, but poor secondary
clarification is a problem in most cases.  The reasons for this are
not certain.  A high level of COD remains after biological treatment,
indicating that much of the wastewater constituents are biologically
refractory.

               Solution Crumb Plants - Advanced

Advanced or tertiary treatment technologies have not been used on
secondary effluents from solution crumb plants.  It  is very probable
that activated carbon treatment would give COD removals similar to
those for emulsion crumb wastewater, since the raw wastewater con-
stituents (for example, traces of monomer) are similar for both types
of wastewater.

               Latex Plants - Primary

Since latex plant wastewaters contain uncoagulated  latex  solids,
primary clarification  is with chemical coagulation  and sinking.
In much the same manner as for emulsion crumb wastewaters, clarifica-
tion can be effected in reactor-clarifiers or systems with separate
rapid mix, flocculation, and clarification tanks.   Latex  wastewaters
can also be clarified by air flotation.

               Latex Plants - Secondary

Activated sludge plants are used  for the  secondary  treatment  of latex
wastewater.  High  residual COD  levels are  a  problem.  These  levels are
higher than for either emulsion crumb or  solution crumb  plants, because
the COD loading of the raw wastewater from latex plants  is much higher.
It  is feasible that aerated  lagoons  and  stabilization ponds  will  produce
satisfactory oxidation and stabilization  of  latex wastewaters.
                                  VI1-

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                                                                    DRAFT
               Latex Plants - Advanced

Advanced or tertiary treatment technologies have not been used on latex
wastewaters.  It is probable that COD removals similar to those achieved
by emulsion plants could be achieved for latex wastewater by using
activated carbon columns.
                                    VII-

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                                                              DRAFT
                          SECTION VI I I

           COST, ENERGY AND NON-WATER QUALITY ASPECTS

Tire and Inner Tube Industry

     Selection of Control and Treatment Technologies
     Based on Costs

Two alternative approaches exist for the control  and treatment  of
process wastewaters from both old and new tire and inner tube  pro-
duction plants.

The first approach is to combine process and non-process wastewaters  and
to treat the entire plant effluent.  Where land is available,  end-of-
pipe treatment is the approach favored by many of the tire manufacturers,
Generally, the reasons supporting this approach are as follows:

     1.  In older plants, in-plant sewers for process and non-process
         wastewaters are usually combined, thus making combined
         treatment more attractive.

     2.  Process flows are usually small relative to non-process flows.

     3.  The treatment of non-process wastewaters has received  the
         bulk of industry's attention.   High suspended solid loadings
         in blowdown and water treatment wastes are the major  pollutant
         in the combined plant effluent from tire facilities.

However, end-of-pipe treatment systems also have several disadvantages:

     1.  The combined effluent treatment system usually requires one
         or two lagoons for settlement and retention.  Lagooning of
         the wastes requires large land area, which is not readily
         available at many plant locations.

     2.  Because of dilution, the effectiveness of treatment for oil
         removal from process wastewater is reduced.  In several of
         the systems observed, oil passed through untreated (although
         it was present in significant quantities), because its concen-
         tration was below the capabilities of the treatment system
         emp1oyed.

The second approach employed is control and treatment of a segregated
and undiluted process wastewater.  This approach has been followed
in plants having partially or wholly segregated process and non-
process sewers.  This would, of course, include any plant using recir-
culated cooling water.  The main advantages for this treatment scheme
over combined end-of-pipe treatment are:
                            VI11-1

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                                                                   DRAFT
     1.   Higher pollutant removal  rates.

     2.   Smaller land area required for treatment  facilities.

The primary disadvantage of a segregated  system approach  is  that
separate process and non-process sewers are required.

Upon examining these alternatives, control  and treatment  of  segregated
process  wastewaters was considered to be most applicable  to  the
tire producing industry.  End-of-pipe treatment of combined  wastewaters
is not feasible for pollution control because of:  1)  the  ineffectiveness
of such  systems in removal of process wastewater contaminants; and
2) the large land requirements.  All costs, therefore, are related  to the
treatment of a segregated process waste stream.

With proper in-plant control, the process streams consist of readily
separable lubricating and extender oils and settleable solids.
Volumetric flow rates for process wastewaters are small.   Therefore,
the initial treatment applicable from a cost and proven operation basis
Is an API-type gravity separator.  The performance and efficiency
of a gravity separator can be improved by addition of an absorbent
filter.

Effluent quality data for old tire and inner tube and for new tire
facilities are presented  (along with cost data) in Tables Vlli-1 and
VII I-2.   The treatment technology  involves the  isolation of wastes
with curbing,  the protection of oily areas to  prevent storm runoff
contamination, and  the separation  of settleable solid and oily material
from the wastewater.

A  more detailed description  of  recommended facilities is presented  in
the tire and  inner  tube  portion of Section IX,  and a  flow diagram of
the system used as  a basis for  costing  is  presented in Figure IX-1.

     Treatment Cost  Data
 Data  from Corps of  Engineers  permit  applications  and  plant data^obtained
 during  inspection visits were used to obtain  the  average  or  typical
 plant size and wastewater  discharge  flows,  and  raw waste  loadings
 as  described  in Section V.

 From  these data, a  typical  process wastewater flow was  estimated to
 be  3.785  liters/sec (60 gal/min)  for a plant  consuming  205,000  kg
 (450,000  Ibs) of raw materials per day.   For  the  old  tire and  inner
 tube  plant sub-category the average  oil  loading is 0.2^6  kg/1,000^
 kg  of raw material  consumed.   The suspended solids load.ng for^th.s
 sub-category  is estimated  to be 0.319 kg/1,000 kg of  raw  material.
                             Vlll-2

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                                                 TABLE VIII  - 1
                            Old Tire and Inner Tube Production Facility Subcategory

                    Estimated Wastewater Treatment Costs for Different  Degrees  of Treatment
                      based on a Typical Raw Material  Consumption of 205 metric tons/day
Investment

Annual Costs
  Capital Costs
  Deprec iation
  Operating and Maintenance Costs
    (excluding energy and power costs)
  Energy and Power Costs
                  2
Total Annual Costs
Parameters
     O^ kg  raw material)

Suspended Sol ids

0 i 1 and Grease
                                                          Treatment  or Control  Technology
                                                                                         1




ists
• costs)


Raw
Waste Loads
0.319
0.120
_A_
$299,000
$ 30,000
60,000
24,000

1,000
$115,000

A
0.064
0.048
B
$328,000
$ 33,000
66,000
27,000

1,000
$127,000
Effluent Oual ity
B
.064
.008
    Technology A  is  Isolation of Wastewaters followed by API  Gravity  Separator
    Technology B  is Technology A followed by an Absorbent Filter
    2
    August  1971 Dollars
73
                                                                                                                  T|
                                                                                                                  -i

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                                                      TABLE VI I I  - 2

                                       New Tire Production Facility Subcateqory


                         Estimated  Wastewater Treatment Costs for Different Degrees of Treatment
                           based on a Typical Raw Material Consumption of 205 metric tons/day
     Investment

     Annual  Costs
       Capital Costs
       Depreciation
       Operating and Maintenance Costs
        'excluding energy and power costs)
       Energy  and Power Costs

<                     2
—    Total Annual Costs
i
-P-
                                                               Treatment or Control Technology
                                                          __
                                                       $276,000
                                                       $ 28,000
                                                         55,000
                                                         22,000

                                                          1,000

                                                       $106,000
                                                      JL
                                                   $305,000
                                                   $  31,000
                                                     61,000
                                                     25,000

                                                      1.000

                                                   $118,000
     Parameters
     (kg/10^  kg  raw materfal)

     Suspended Sol ids

     Oi 1  and  Grease
Raw
                                                                        Effluent Ouality
Waste Loads
0.319
0.083
A
0.064
0.048
B
0.064
0.008
         Technology A  is  Isolation of Wastewaters followed by API  Gravity Separator
         Technology B  is  Technology A followed by an Absorbent Filter
        >
         August  1971 Dollars
                                                                                                                        o
                                                                                                                        73
                                                                                                                        •

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                                                                   DRAFT
Based on these typical profiles for old and new production  facilities,
treatment cost data were generated and are presented in Tables  VII 1-1
and Vlll-2.  Costs typically are higher for older production facilities,
primarily due to the fact that a new in-plant process sewer system
would be needed.  Separation of the present combined system was
considered unrealistic for older production plants.

Investment costs have been factored to August 1971 dollars  using Engin-
eering News Record cost indices.  Depreciation was calculated on the
basis of straight-line depreciation with a five year life and zero
salvage value.

Designs for the proposed model treatment systems were costed out in
order to aid EPA in its efforts to evaluate the economic impact of
the proposed effluent limitations.  The design considerations (i.e.,
the influent raw waste  loads) were selected to represent the expected
raw waste  load within each sub-category.  This results in the generation
of cost data which should be conservative when applied to most of the
plants  in  this category.  Relatively conservative cost figures are
preferred  for this type of general economic analysis.

The capital costs were  generated on a  unit process  basis, with the
following  "percent add  on" figures applied to the total unit process
costs in order  to develop the total installed capital cost  requireme
                                                           requirements.

                                                  Percent of Unit
          ..
          I tern
     Electrical                                           12
     Piping                                              1j>
     Instrumentation                                      °
     Site work                                            '
     Engineering Design and Con-
        struction Supervision Fees                       10
     Construction Contingency                            15

Since land costs vary appreciably between plant locations, it was
decided to exclude land cost from the total capital cost estimates
Land costs must be added on an individual case basis.

Annual costs were computed using the following cost basis:
                             VIII-5

-------
                                                                    DRAFT
           ltem                            Cost Allocation

      Capitalization         10  percent  of  investment

      Depreciation           5-yr  straight  line with zero salvage value

      Operations  and         Includes  labor and supervision, chemicals,
        Maintenance          sludge  hauling and disposal, insurance and
                            taxes  (computed at 2  percent of the capital
                            cost),  and  maintenance  (k percent of capital cost)

      Power                  Based on  $0.01 kw-hr  for electrical power.

The  short-term capitalization  and  depreciation write-off period is
what is currently acceptable under current Internal Revenue Service
Regulations pertaining  to  pollution  control equipment.

All  costs were computed  in  terms of  August, 1971 dollars, which corres-
pond to an Engineering  News Record Index  (ENR) value of 1580.

      Energy Requirements

Energy  input  is  related  to  the need  for electric pumps to pump process
wastewaters from the plant  area and  through the  treatment system.
Electricity costs are estimated at one cent per  kilowatt hour.  The
extra power required for treatment and control systems is negligible
compared to the  power requirement  of the  tire manufacturing equipment.

      Non-Water Quality Aspects

The  primary non-water quality aspect deriving from use of a separator
is the need for disposal of oil and  solids.  Additional solid waste
results from  the use of a non-regenerative type absorbent filter.

Solid waste disposal is a major problem confronting the industry as
a whole.  Typically, 3,100  kg  (6,800 Ibs) of solid waste are generated
by a  tire plant each day.  Additional  solid waste results from the drum-
ming  of the waste solutions for off-site  disposal.  Many manufacturing
plants, particularly in the northern states, are finding it difficult
to locate and arrange for service  at satisfactory landfill sites.
Fortunately,  the additional solid  waste generated by the proposed
treatment technology is very small relative to the normal solid waste
generated by  the production facility; consequently, the impact will
not  be significant.

Land  requirements for the treatment  system are small; nevertheless,
certain older facilities located in  highly congested urban areas will
find  it difficult to allocate space  for even this minimal treatment
facility.  These plants may be forced to  turn to other control measures
and/or to pre-treat for disposal and discharge of the process wastewaters
.to publicslly owned treatment works.


                             VI I I-6

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                                                                    DRAFT
Synthetic Rubber Industry

     Emulsion Crumb Sub-category

          Selection of Control and Treatment Technologies

Four degrees of control and treatment were considered in weighing
treatment effectiveness versus cost of treatment:  primary  clarifica-
tion; biological oxidation; and advanced treatment to two  levels
of COD removal.

Since emulsion crumb wastewaters contain uncoagulated latex solids,
it is necessary to coagulate these solids prior to clarification.  The
cost alternatives for the primary clarification of emulsion crumb
wastewater have been developed on the basis of a treatment model  invol-
ving chemical coagulation, with a sinking material such as clay to sink
the coagulate.d solids.  This, however, is only one of several  possible
methods of achieving primary clarification.  Air flotation is  another
approach to primary clarification which has been applied to emulsion
crumb wastewaters with success.  Chemical coagulation has  been used to
develop the cost data because there are more cases of its  successful
application for this type of wastewater, and, therefore, there is  less
uncertainty about the effectiveness of this technology for this sub-
category.

After primary clarification, emulsion crumb rubber wastewaters in-
variably have high BOD and COD concentrations.  Biological treatment
is necessary (and is commonly practiced by the industry) to remove
these contaminants.  In order to develop the cost alternatives for
biological treatment, activated sludge processes were used as  a
model treatment.  It is, of course, only one method for obtaining
biological oxidation, since other comparable technologies, such as
aerated lagoons and stabilization ponds exist and are used to  some
extent by the industry.  The activated sludge process was  chosen
as a model treatment because its performance is not as temperature-
and climate-dependent as is an aerated lagoon or stabilization pond
system and because the resulting cost data are independent of  geo-
graphic location.  In addition, an aerated lagoon or stabilization
pond system requires considerably larger areas, which are  not  always
available.  Activated sludge facilities, by contrast, require  minimal
land.

The major pollutant remaining in emulsion crumb wastewaters after  bio-
logical treatment is COD.  Its concentration is much higher than the
other principal parameters and if advanced wastewater treatment is to be
carried out, it is logical that the treatment technology should be
applied to reduction of the high COD  levels.  For the wastewater flow
rates involved in emulsion crumb rubber production, activated  carbon
                             VIII-7

-------
                                                                    DRAFT
treatment is the only technology applicable for COD removal.   In  order
to prevent blinding of the carbon beds and columns with fine  suspended
solids, a dual-media filtration system is required upstream of the
columns.  Activated carbon adsorption of emulsion crumb secondary
effluent has been studied in pilot-scale test equipment.  However,
because of the technical risk with respect to performance and the
uncertainty of the associated capital and operating costs, two levels
of activated carbon treatment have been modeled.  These two levels are
equivalent to overall COD reductions of 75 and 90 percent.

          Basis of the Treatment Cost Data

An emulsion crumb industry profile was made, based on industry produc-
tion capacity data, to determine the typical size of an emulsion
crumb production facility.  The average, or typical, plant is rated
at 128,000 metric tons per year.  The wastewater flow for such a  plant
would approximate 66 liters/second (1,050 gallons per minute). The
model treatment plant, using chemical coagulation and clarification
followed by activated sludge biological treatment, is shown in Figure
IX-2.  The degree of treatment afforded by this technology is equi-
valent to Level I  Control and Treatment.  The recommended treatment
technology to attain Level II control and treatment is presented  in
Figure X-1.  This treatment technology includes dual-media filtration
followed by activated carbon adsorption.

Designs for the proposed model treatment systems were costed  out  in
order to aid EPA in its efforts to evaluate the economic impact of
the proposed effluent limitations.  The design considerations (i.e.
the influent raw waste loads) were selected to represent the  highest
expected raw waste load.  This results in the generation of cost
data which should be conservative when applied to most of the plants
In the emulsion crumb sub-category.  Relatively conservative  cost
figures are preferred for this type of general economic analysis.

The capital costs were generated on a unit process basis, with the
following "percent add on" figures applied to the total unit  process
costs in order to develop the total installed capital cost requirements,
                                                 Percent of Unit
             I tern                             Process Capital Cost

     Electrical                                        12
     Piping                                            15
     Instrumentation                                    8
     Site Work                                          3
     Engineering Design and Con-
       struction Supervision Fees                      10
     Construction Contingency                          15
                             VII I-8

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                                                                   DRAFT
Since land costs vary appreciably between plant locations,  it was decided
to exclude land cost from the total  capital  cost estimates.  Land
costs must be added on an individual case basis.

Annual costs were computed using the following cost basis:

         I tern                                 Cost Allocation

     Capitalization      10 percent of investment

     Depreciation        5-yr straight line with zero salvage value

     Operations and      Includes labor and supervision,  chemicals,
       Maintenance       sludge hauling and disposal, insurance  and
                         taxes (computed at 2 percent of  the capital
                         costs), and maintenance (computed  at k  per-
                         cent of the capital cost).

     Power               Based on $0.01/kw-hr for electrical power.

The short-term capitalization and depreciation write-off  period  is
what is currently acceptable under current  Internal Revenue Service
Regulations pertaining to industrial pollution control equipment.

All costs were computed in terms of August, 1971 dollars  which  corres-
pond to an Engineering News Record  Index  (ENR) value of 1580.

The total capital and annual costs for the model treatment  techno-
logies are presented for a typical emulsion crumb plant in  Table VIII-3,
together with raw waste load and treated effluent quality.

          Energy Requirements

The primary clarification and biological oxidation treatment tech-
nologies  require electrical energy only for operation of equipment  such
as pumps and aerators.  The filtration and activated carbon treat-
ment system, in addition to power requirements, needs a fuel source
to regenerate the carbon.  The energy and power needs of the recommended
treatment technologies are deemed to be modest.

          Non-Water Quality Aspects

Sludge cake is produced by vacuum filtration of the primary coagulation
solids and the digested biological solids.  Sludge disposal costs were
based on sanitary  landfill.  Sludge incineration costs were not eval-
uated because the economics depend, to a  large degree, on the accessi-
bility of a landfill site and on the relative costs for sludge haulage
and site disposal.  The annual quantities of solid waste generated  are:
                             VII1-9

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                                                         TABLE V I I I - 3

                                               Emulsion Crumb Rubber Subcategory
i
o
   Investment

   Annual Costs
     Capital Costs
     Deprec iat ion
     Operating and Maintenance Costs
      (excluding energy and power costs)
     Energy and Power Costs
                     2
   Total Annual Costs
Parameters
(kg/10-3 kg product

COD
BOD

Suspended Solids

0 i 1 and Grease
   Raw
Wastewater
ter Treatment Costs for Different Degrees of Treatment
cal Production Capacity of 128,000 metric tons/year


$1
$
$






A
,180,000
118,000
236,000
1^7,000
10,000
511,000

A
12.80
2.00
1.2S
0.32
Treatment or Control
t! (Level 1)
$2,002,000
$ 200,000
400,000
230,000
20,000
$ 850,000
Effluent <"ual ity
B (Level 1)
8.00
0.40
0.65
0. IS
Technoloq ies
C
$2,907,000
$ 291,000
581,000
349,000
25,000
$1,246,000

C
5.04
0.08
0.08
0.03

D aevel 1 1)
$2,993,000
$ 299,000
599,000
396,000
29,000
$1,323,000

D (Level 1 1)
2.08
0.08
0.16
0.08
                               20.00

                                2.13
                                7.20

                                1 .40

    Flow  (L/10   kg  production)  16,600

       Technology  A  is Chemical Coagulation followed by Clarification.
       Technology  B  is Technology A followed by Activated Sludge Secondary Treatment
       Technology  C  is Technology B followed by Dual Media Filtration plus Activated Carbon Treatment to produce 75% overall
           COD  reduction.
       Technology  D  is Technology U followed by Dual Media Filtration plus Activated Carbon Treatment to produce 90% overall
           COD  reduction.

      2August  1971 Dollars.
                                                                                                                              o
                                                                                                                              73
                                                                                                                              •

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                                                                   DRAFT
     Primary coagulated solids            2,9^0 cu.  meters  (3,900  cu. yds)

     Biological solids                      2^5 cu.  meters  (325  cu. yds)

     Solution Crumb Sub-category

          Selection of Control and Treatment Technologies

Only two degrees of control and treatment have been considered in  the
evaluation of treatment effectiveness versus cost data.   Since latex
solids are not contained in wastewaters from solution crumb plants,
clarification with chemical coagulation is not required;  clarifi-
cation in crumb pits is sufficient.  In addition, after  biological
treatment, the residual COD concentration is much lower  than is  the
case in the emulsion crumb couterpart.  Consequently, carbon adsorption
to only one level of overall COD reduction (65 percent removal)  is
reasonable.  COD reductions greater than this would involve additional
risk and uncertainty in the costing processes.

The first degree of treatment proposed includes primary  clarification
of crumb-laden wastewater in dual-unit crumb pits, followed by bio-
logical treatment to remove soluble organics.  The cost  data have
been developed on the basis of an activated sludge system for the  same
reasons as given previously for the emulsion crumb sub-category.
Depending on land availability, biological treatment could  be aerated
lagoons and stabilization ponds.  The second degree of treatment
consists of dual-media filtration followed by activated  carbon, adsorp-
tion.  Carbon adsorption was selected because it is the  most feasible
technique for reducing the soluble COD content.

          Basis of the Treatment Cost Data

A profile of the solution crumb rubber industry defined  the typical
size of a solution crumb production facility as 30,000 metric tons
per year.  The wastewater flow for such a plant would approximate
15.75 liters/second (250 gallons per minute).

The model treatment plant using activated sludge biological treat-
ment is shown in Figure IX-2.  The treatment given by the proposed
system is equivalent to Level I Control and Treatment.

The recommended treatment technology to attain Level II  Control  and
Treatment, presented in Figure X-1, consists of dual-media  filtration
followed by activated carbon adsorption.

The influent raw waste loads upon which the treatment system designs
were based were selected to represent the highest expected  raw waste
load in this sub-category.  The same cost criteria used  for emulsion
crumb plants were applied for solution crumb rubber facilities.
                             VIII-11

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                                                                    DRAFT
The total capital and annual costs for the model treatment techniques
for a typical  solution crumb plant are presented in Table VI I 1-4,
together with  the raw waste loads and treated effluent qualities.

          Energy Requirements

The only energy or power need is electricity, and electricity consump-
tion is moderate.  The carbon is not regenerated on-site because of
the unfavorable economics of small-scale carbon regeneration systems.

          Non-Water Quality Aspects

Solid waste generation with this treatment system is associated with
biological solids and spent activated carbon.  The activated carbon
canisters may  be returned for regeneration off-site by the supplier.
However, annual operating data have been based on disposal of the
spent carbon at a landfill site.  The annual quantities of solid waste
generated are:

     Biological solids                   102 cu. meters  (135 cu. yds)

     Spent carbon                        1*fO cu. meters  (185 cu. yds)

Air quality and noise levels will not be significantly affected by
the operations proposed in these treatment systems.

     Latex Sub-category

          Selection of Control and Treatment Technologies

Four degrees of control and treatment were considered in weighing the
treatment effectiveness versus cost of treatment.  These degrees of
treatment are  the same as for emulsion crumb wastewater and include
primary clarification, biological oxidation, and advanced treatment
to two levels  of COD removal.

Latex rubber wastewaters contain uncoagulated  latex solids and the
proposed primary treatment  (chemical coagulation and clarification)
is similar to that recommended for emulsion crumb wastewaters.  The
biological treatment cost data have been based on activated sludge
for the same reasons as were cited for the emulsion crumb sub-category.
The advanced treatment cost data were modeled  on two  levels of overall
COD reduction, 8? and 95 percent.  Overall removals greater than 95
percent would  call for undue technical risk, and uncertainty about
capital and operating costs.
                             VII 1-12

-------
                                                 TABLE VI I 1-4

                                       Solution Crumb Rubber Subcateqory
                    Estimated Wastewater Treatment Costs for Different Degrees of Treatment
                      based on a Typical Production Capacity of 30,000 metric tons/year

                                                          Treatment or Control Technologies
Investment
Annual Costs
  Capital Costs
  Deprec iat ion
  Operating and Maintenance Costs
    (excluding energy and power costs)
  Energy and Power Costs

                  2
Total Annual Costs
 Parameters
 (kg/10-3  kg production)
 COD
 BOD

 Suspended Sol ids

 Oi 1  and  Grease
1

>sts
• costs)
Raw
Wastewaters
6.00
0.80
2.20
0.25
_£L
$810,000
$ 81,000
162,000
68,000
4,000
$315,000

A (Level
3.9^
0.40
0.65
0.16
	 B_(Level ||
$1,182,000
$ 182,000
236,000
1^5,000
6,000
$ 569,000
Effluent Dual ity
1) B (Level 1 I)
2.08
0.08
0.16
0.08
    1
     Technology A  is Primary Clarification of Crumb Rinse Wastewaters followed  by  Activated  Sludge Secondary
     Treatment.
     Technology B  is Technology A followed by Dual Media Filtration plus  Activated Carbon  Treatment  to pro-
     duce  65% overall COD  reduction.
    I
    "August  1971 Dollars.

-------
                                                                    DRAFT
          Basis of the Treatment Cost Data

A latex rubber industry profile was made to determine the typical  size
of a latex rubber production facility.  The average, or typical,  plant
has an annual capacity of 10,000 metric tons, and its wastewater  flow
approximates k.k liters/second (70 gallons per minute).

The model treatment plant, consisting of chemical coagulation and
clarification followed by activated sludge biological treatment,  is
illustrated in Figure IX-2.  This is equivalent to Level I  Control  and
Treatment.

The recommended treatment technology to achieve Level II Control  and
Treatment technology, presented in Figure X-1, includes dual-media
filtration followed by activated carbon adsorption.

The treatment designs upon which the cost data are based correspond
to the highest expected raw waste load within each category.

The same cost criteria used for the emulsion crumb sub-category
were applied to latex rubber.  See Table VI I 1-5.

          Energy Requirements

Since on-site carbon regeneration is not proposed for economic reasons,
the only power or energy requirement of these treatment systems is
electric power for pumps and other motive equipment.

          Non-Water Quality Aspects

Solid wastes are produced by chemical coagulation and clarification,
wasted biological sludge, and spent activated carbon.  For cost purposes,
it is proposed that these all be hauled to a landfill.  The annual
quantities of solid wastes are listed below:
     Primary coagulated solids           21*t cu. meters (283 cu.  yards)

     Biological  solids                    62 cu. meters (82 cu.yards)

     Spent carbon                        126 cu. meters (167 cu.  yards)

Neither air quality nor noise levels will be adversely affected  by
the proposed treatment technologies.

-------
                                                       TABLE VI11-5

                                                Latex Rubber Subcateqory
Investment

Annual Costs
  Capital Costs
  Depreciat ion
  Operating and Maintenance Costs
    'excluding energy and costs)
  Energy and Power Costs
                  2
Total Annual Costs
 Parameters
 (kg/10^  kg production)

 COD

 BOD

 Suspended Sol ids

 0i 1  and  Crease
    Raw
Wastewater

   33.52
    5.61

    5.63
    0.70
ater Treatment Costs for Different Degrees of Treatment
ypical Production Capacity of 10,000 metric tons/yr.
Treatment or Control Technologies
A
$361,000
$ 36,000
72,000
33,000
1 ,000
$142,000

.,-/,•—
14.75
4.77
0.93
0.34
J_ (Level 1)
$637,000
$ 64,000
127,000
57,000
3,000
$251 ,000
Effluent Cual ity
_B_ (Level 1)
6.35
0.34
0.55
0.14
JL
$784,000
$ 78,000
157,000
100,000
3,000
$33^,000

V
4.31
0.07
0.07
0.07
JL (Level II)
$784,000
$ 78,000
157,000
117,000
3,000
$355.000

JL (Level II)
1.78
0.07
0.14
0.07
     Technology A  is  Chemical Coagulation followed by Clarification.
     Technology B  is  Technology A  followed by Activated Sludge Secondary Treatment.
     Technology C  is  Technology B  followed by Dual Media Filtration plus Activated Carbon Treatment to produce 37% overall
        COD  reduction.
     Technology D  is  Technology B  followed by Dual Media Filtration plus Activated Carbon Treatment to produce 95% overall
        COD  reduction.                                                                                                      g
   2                                                                                                                       >
     August  1971  Dollars.                                                                                                   Z{

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                                                                    DRAFT
                           SECTION IX

              BEST PRACTICABLE CONTROL TECHNOLOGY
          CURRENTLY AVAILABLE — EFFLUENT LIMITATIONS


Tire and Inner Tube Facilities

     Identification of Best Practicable Control Technology
     Currently Available

The best control and treatment technologies currently in use emphasize
in-house control of solution wastes with end-of-pipe treatment of com-
bined process and non-process wastewaters.  However, as discussed
previously, end-of-pipe treatment of process wastewaters after combi-
nation with non-process wastewaters  is considered  ineffective.

Of the exemplary plants visited, only one plant  performs a totally
adequate end-of-pipe treatment of all process  wastewater streams.
The treatment facility  involves the  use of holding  lagoons for com-
bined process and non-process effluents and the  re-use of the
wastewater for  irrigation of  farm  land.  The very  large  land  re-
quirements involved keep this type of treatment  from being applied
to the  industry as a whole.   Other end-of-pipe treatment facilities
examined were not very  effective  in  removal of the  oil constituent
in the wastes,  due to dilution  by  non-process  wastewaters.

There are many  in-plant control and  treatment  facilities.  Recircula-
tion of the soapstone solution  was considered  adequate and effective.
However,  the weekly washing  and dumping  of  the system  in most plants
reduced this effectiveness.   Oil  sumps  and  separators  are common  to
the  tire  industry, but  their effectiveness  is  reduced  by  dilution
with other wastes or  by improper  maintenance.

Since process wastes  are  best treated before  dilution  with  non-process
wastewaters and because no plant  obtained effective control  and  treat-
ment  for  all  the  wastewaters it generated,  the proposed  Level 1
 treatment technology  for  a typical  plant is_a combination of the best
 features  of various  plants examined  and visited.

 Since only the  loadings vary between the Old Tire and Inner Tube
 Production Facilities sub-category and the New Tire Production
 Facilities sub-category,  the treatment schemes described below
 will  be the same for both.

 Basically, the technology employed consists of:

      1    Elimination of any discharge of soapstone or latex-dip solution.
      2.  Segregation, control, and treatment  of all oily waste streams.


   NOTICE-   THESE  ARE  TENTATIVE RECOMMENDATIONS BASED UPON INFORMATION
   TTTHTS REPORT AND ARE  SUBJECT TO CHANGE BASED UPON COMMENTS RECE.VED-
   AND  FURTHER INTERNAL  REVIEW BY EPA.
                                 IX-1

-------
                                                                    DRAFT
A flow diagram of the proposed system is shown in Figure IX-1.

Zero discharge of soapstone and latex solutions is currently practiced
by production facilities in each of the sub-categories.  Elimination
of soapstone solution discharges involves:

     1.  Recycle of soapstone solution.
     2.  Installation of curbing around the soapstone dipping area.
     3.  Sealing of drains in the dipping area.
     k.  Re-use of the recirculating system washwater as make-up
           for fresh soapstone solution.

The re-use of the recirculating system washwater  is the key to zero
discharge of this waste.   In emptying the system  for cleaning, the
soapstone used should be stored in tanks.  The washwater used should
also be collected and stored.  Once the system is cleaned, stored
soapstone can then be returned to the system for  use in the new
production batch.  The collected and stored washwater can then be
re-used as make-up water to  the soapstone bath during the normal
production run.

Eliminating the discharge  of  latex solution  is achieved by:

     1.  The use of curbing  around the  latex dipping area.
     2.  Sealing of all drains  in the dipping  area.
     3.  Containment of all  wastewaters from the  area.

Several plants have already  achieved zero discharge  by  these methods.
The contained and collected  wastes are  disposed of off-site  in a  land-
fill.

Control and  treatment of oily waste  streams  involves segregation, col-
 lection, and treatment  of  these wastes.   The wastes  to be  segregated
 include runoff from oil storage and  unloading  areas  and leakage  and
spills in the process areas,  as shown  in  Figure  IX-1.   Press  and  mill
basins, when present, are  included  in  the process area.

To  achieve proper segregation of wastes,  any  possibility  of  mixing
process and  non-process streams must be eliminated.  This^requires
 two completely segregated  sewer  systems,  proper  plant  piping,  and
 good housekeeping and employee  awareness.   As  a  basis  for  this study,
 it  was assumed that  plants categorized as "old"  have combined sewers.
To  segregate sewers  properly in  plants of the "old"  sub-category, it
was deemed  necessary  to install  completely new drains  and  sewer  lines;
 existing  drains  would be  sealed  off.    Older plants  often have a sig-
 nificant  number  of  drains  and sewer  runs in which the location and
 interconnection  are  often  doubtful  because of outdated eng.neermg
 and installation drawings.  It  would,  therefore,  be  less costly to
 install  new plant  sewers  properly  segregated than attempt to red.rect
 the existing ones.

  NOTICE-  THESE ARE TENTATIVE  RECOMMENDATIONS BASED UPON  INFORMATION
  JFTTHTS REPORT AND ARE SUBJECT TO  CHANGE  BASED  UPON  COMMENTS RECEIVED
  AND  FURTHER  INTERNAL  REVIEW BY EPA.
                               IX-2

-------
                                                                    FIGURE IX-1

                        HYPOTHETICAL WASTEWATER  SEGREGATION AND TREATMENT  FACILITY FOR TIRE AND  INNER TUBE PLANTS
ROOFED TANK CAR UNLOADING AREAS
                               ROOFED TANK TRUCK UNLOADING AREAS
                     	i\.
                                P—• —- — o^>~
                                                H
                                                      	n     n__        	n     n	      	n
                     0"
                 t^
                                       tntir.f UilN
                    SUUPS
STORAGE
 1ANK  ^
                                                         FURTHER
                                                         TREATMENT
                                                         FOR OIL
                                                         REMOVAL
                                                                          0!L
STRA*
FILTER
                                                                   SIMP
                                                                                           SANITARY
                                                                                           UNDF!U
                                                                                                        GENERAL PAVED AREAS
£)
                                                +
                                                 I
                                                 I
                                                 I —
                                                                                                            PROCESS EFFLUtNT
                                                                                                            MONITORING STATION





1
1
;
ADSORBENT
FILTER
                                                                                                                                                EFFLUENT
                                                                              FINAL EFFLUENT
                                                                              MONITORING STATIW

-------
                                                                    DRAFT
Once isolated, these wastewaters are collected in sumps located in
strategic areas throughout the plant.  Waste flows will be intermittent
by nature and, therefore, a sizable flow rate will hardly ever be ob-
tained without first collecting all wastes in centralized locations.
Wastewaters collected in these sumps will be periodically pumped to
an API-type gravity separator, where the separable oil and solids
fraction is removed.  To provide for large spills or  leakage of a
major water supply line, a 37,850-liter (1,000-gal.)  storage tank
is provided.

Separated oil is removed by a manually operated slotted pipe.  A decant
tank is provided to allow water removed with the oil  to settle out.
Concentrated oi1-water mixtures are then removed from the decant tank,
drummed, and sealed, and sent to a landfill.  Water removed from the
tank is pumped back to the separator.

Settleable solids collected in the separator are periodically removed
and also sent to a landfill.  The separator is provided with two dual-
operating chambers in order to provide for uninterrupted service during
clean-out.

The gravity separator is provided with a straw filter to remove any
large oil globules still remaining due to possible short circuiting
or unforeseen peak overload conditions.  Additional treatment for oil
removal is obtained by passing the effluent from the  separator through
an absorbent filter.

     Effluent Loadings Attainable With Proposed Technologies

Based on the control technology data obtained from tire manufacturer
sources, and treatment data obtained from industries  having similar
wastewater problems, it was determined that the proposed Level 1 control
and treatment technologies will result in the following effluent quality
for both Old Tire and Inner Tube and New Tire Facilities:

               Oi1 and Grease        5 mg/L
               Suspended Solids     ^0 mg/L

It is expected that the use of an API separator will  result in an ef-
fluent oil  concentration of 30 mg/L.  The use of an absorbent filter
will  further reduce the effluent oil concentration to 5 mg/L.

A reduction in suspended solids concentration will result from the use
of the proposed API-type gravity separator.  Additional reduction in
suspended solids is deemed likely after passage through the absorbent
filter.  However, no reliable data are available for making such a
determination.  As a result, recommended standards for Level 1 are
as follows:
               Suspended Solids      0.6** kg/103^kg raw material
               Ojl                   0.008 kg/10  kg  raw material

  NOTICE:  THESE ARE TENTATIVE RECOMMENDATIONS BASED  UPON  INFORMATION
  IN THIS REPORT AND ARE SUBJECT TO CHANGE BASED UPON COMMENTS RECEIVED
  AND FURTHER INTERNAL REVIEW BY EPA.
                               IX-4

-------
                                                                    DRAFT
Synthetic Rubber Industry

     Identification of Best Practicable Control  Technology
     Currently Available

In view of the fact that all sub-categories of the synthetic rubber
industry are highly technical and proprietary in nature, it is not
possible to base effluent limitation guidelines and standards of
performance on in-plant control technologies which might impact on
processing procedures and product quality.   Instead, these guidelines
have been formulated around the best practicable end-of-pipe treat-
ment technologies employed by the synthetic  rubber industry.  In order
to achieve the contaminant reductions recommended for this guideline,
the synthetic rubber industry v,-i 1 1  require better housekeeping and
maintenance practices, as well as in-plant processing modifications,
to assist the end-of-pipe treatment plant  in attaining the required
reductions.  The effluent limitations have been based on the effluent
quality and contaminant removal efficiencies of well-designed and
properly-operated treatment facilities.   Level  1 technology has been
defined as equivalent to secondary treatment.

          Emulsion Crumb Sub-category

The coagulation  liquor and crumb rinse overflow stream should be passed
through crumb pits to remove crumb rubber  fines.  These pits should be
be dual units so that good crumb separation  can be achieved during pit
unit cleaning operations.  Figure IX-2 shows a hypothetical end-of-pipe
secondary treatment facility applicable to the  treatment of emulsion
crumb wastewaters.  This treatment includes  chemical coagulation and
clarification, and biological  treatment.   The total plant effluent
should be passed through an equalization  basin, providing approximately
2k hours detention, to smooth  out waste  load peaks and to equalize
hydraulic flow.  The equalization basin  should  be aerated to  insure^
good mixing, prevent anaerobic  conditions, and  assist  in the biological
oxidation removal process.

From the equalization basin,  the wastewaters are  pumped to  a mixing
basin, where the pH of the wastewaters  is adjusted to  achieve optimum
coagulation conditions.  The  desired  pH  value  is  approximately  neutral
(pH=7) and  is suitable for  biological  treatment with no changes. ^
Nutrients to facilitate biological treatment will also be added in this
basin.

After pH adjustment, the wastewaters  flow into  a  reactor-clar if ier ,
where coagulating chemicals  (alum and polyelectrolyte)  are  added in
the reactor compartment.  A  clay slurry  is also added,  to weight down
the coagulated  rubber  solids.   The wastewater  flows  from  the  reactor
compartment to  the clarifier,  where  the  settleable  solids  and  coagulated
solids  settle and are  removed.   The  clarified  wastewater  overflows the
clarifier  and enters  the biollgical  treatment  system.

           THESE ARE TENTATIVE  RECOMMENDATIONS  BASED UPON  INFORMATION
          R™ORT AND ARE SUBJECT TO  CHANGE BASED  UPON  COMMENTS  RECEIVED.
  AND FURTHER  INTERNAL  REVIEW  BY  EPA.
                               IX-5

-------
                                                                 FIGURE  IX-2
                              HYPOTHETICAL  END-OF-PIPE SECONDARY  WASTEWATER TREATMENT FACILITY
                                                       FOR SYNTHETIC RUBBER PLANTS
                             ACID
                                                                        CLAY
I
X
r
                                                                                                                     *. 12 J»OVANC ED JIL* ™ 2iT_
                                                                                                                      (REFER TO  SECTION X)
                                    pH ADJUSTMENT
                                    AND NUTRIENT
                                    ADDITION
                                    BASIN

-------
                                                                    DRAFT
The clarified wastewater flows into aeration basins where it  is well
mixed with biological solids.  Micro-organisms synthesize new biologi-
cal solids from organic matter contained in the wastewater.   At the
same time, some soluble matter is consumed for energy purposes using
oxygen supplied by aerators  in the basin.  The result is that soluble
material is converted to insoluble biological solids and the  BOD of
the wastewater is reduced.  The mixed liquor containing biological
solids suspended in the wastewater overflows the aeration basin to
the secondary clarifier.

The solids in the mixed liquor are settled in the secondary clarifier,
and the clarified wastewater overflows and enters an effluent monitor-
ing station, where the flow  is recorded and an automatic 24-hour
composite sample is collected.

Part of the settled biological solids is returned to the aeration basins
to maintain the mixed liquor solids concentration in the basin.  The re-
mainder of the bio-solids must be wasted from the system as a sludge.

The waste sludge is first thickened  in a gravity thickener with the
supernatant returning to the head of the aeration basins.  The thickened
sludge underflow enters an aerobic digestor, where  the biological sludge
is wasted by endogenous respiration utilizing oxygen to aerate and re-
duce the bio-solid bulk.  This process  is  referred  to as aerobic
digestion.

This digested sludge  is then mixed with the  primary solids underflows
from the reactor-clarifier unit  and enters a secondary thickener.  The
clear supernantant from this thickener  is  also recycled to the aeration
basins. The thickened underflow  is then discharged  to a vacuum filter
for further conditioning and concentration.

A  drum-type vacuum filter separates  thickened  sludge into a  dewatered
cake, which discharges  by belt conveyor to a dumpster bin and  into a
filtrate that  is recycled to the aeration  basin.  The dewatered sludge
cake  is biologically  stable  and  can  be  disposed of  at a sanitary land-
fill.   Filter aid and precoat preparations are used to  assist  and
maintain the quality  of the  filtrate.

          Solution Crumb Sub-category

The plant wastewaters are first  passed  through crumb pits  to remove
rubber  crumb fines.   As previously noted  in  the discussion of  the
emulsion crumb sub-category,  these pits  should be  dual  units.

Figure  IX-2  represents  a  hypothetical secondary treatment  alternative
which  is applicable  to  solution  crumb rubber wastewaters,  as well  as
to the  emulsion  crumb wastewaters previously discussed.   Since solution
crumb wastewaters do not  contain uncoagulated  latex solids,  and  if ade-


  NOTICE:   THESE ARE TENTATIVE RECOMMENDATIONS BASED UPON  INFORMATION
   IN THIS REPORT AND ARE SUBJECT  TO CHANGE BASED UPON COMMENTS RECEIVED .
  AND FURTHER INTERNAL REVIEW BY  EPA.
                                 IV-7

-------
                                                                    DRAFT
quate separation of the rubber fines has been achieved in the crumb pits,
neither the chemical coagulation process nor the primary clarifier is  re-
quired.  The wastewaters can then pass from the pH and nutrient addition
basin directly into the aeration basin (refer to Figure IX-2).  In addi-
tion, since there are no primary solids, the second thickener is not
necessary and the wasted biological sludge passes directly from the
digester to the vacuum filter.  The solution crumb secondary wastewater
treatment facility  is similar to the emulsion crumb wastewaters in all
other aspects.

          Latex Sub-category

The model secondary wastewater treatment facility illustrated in
Figure IX-2 is also applicable at latex rubber plants.  Since latex
plant wastewaters contain uncoagulated latex solids, primary clarifica-
tion assisted by chemical coagulation is required.  However, because
latex plants are considerably smaller than emulsion crumb plants, the
wastewater flow rate is much lower.  The lower flow rates indicate the
use of separate rapid-mix, flocculator, and clarifier units, since
small reactor-clarifiers are not practicable in small diameters due to
reduction in efficiency, mixing, and settlement of solids.

Other than this basic difference (due to flow rate only) in the design
of the primary clarification equipment, the secondary treatment facility
for  latex plant wastewaters is identical to that described for emulsion
crumb wastewater.

     Effluent Loadings Attainable With Proposed Technologies

          Emulsion  Crumb Sub-category

Based on raw waste  load and the control and treatment data from emulsion
crumb plants, it was determined that the described proposed control and
treatment technologies will result  in the following effluent quality:

               COD                   500 mg/L
               BOD                    25 mg/L
               Suspended Solids       40 mg/L
               Oil  and Grease         10 mg/L

Effluent quality can also be expressed  in terms of effluent waste  loads,
which are independent of wastewater flow.  These effluent waste  loads,
resulting from the  application of treatment technologies equivalent to
chemical coagulation with clarification and biological treatment, con-
stitute the best practicable control and treatment technology standards
currently available (Level  1) for the emulsion crumb sub-category.
Recommendations for proposed  limitations for Level  1 are:
 NOTICE-  THESE  ARE  TENTATIVE RECOMMENDATIONS BASED UPON  INFORMATION
  IN THIS  REPORT  AND  ARE  SUBJECT TO CHANGE BASED UPON COMMENTS RECEIVED
 AND  FURTHER  INTERNAL  REVIEW BY EPA.
                                IX-8

-------
                                                                    DRAFT
                                      8.00 kg/10^ kg production
                                      0.40 kg/10^ kg production
                Suspended Solids      0.65 kg/10^ kg production
                Oil  and Grease        0.16 kg/103 kg production

           Solution  Crumb Sub-category

 Industry  raw waste  load and  the control  and  treatment  data  indicate that
 proposed  control  and  treatment  technologies  for  solution crumb  rubber
 wastewater will  achieve the  following effluent quality:

                COD                    245 mg/L
                BOD                     25 mg/L
                Suspended Solids       40 mg/L
                Oil  and Grease         10 mg/L

 Effluent  quality  can  also be  expressed in terms  of  effluent waste  loads,
 which  are independent  of wastewater  flow.  These effluent waste  loads,
 resulting from  the  application  of  treatment  technologies equivalent to
 primary clarification  and biological  treatment,  constitute the  best
 practicable  control and treatment  technology  standards currently avail-
 able  (Level  1)  for  the solution crumb sub-category.  Recommendations
 for proposed  limitations  for  Level  1  are:

                COD                    3.94 kg/10^  kg  production
                BOD                    0.40 kg/10^  kg  production
                Suspended  Solids      0.65  kg/10:;  kg  production
               Oil  and Grease         0.16  kg/1015  kg  production

           Latex Sub-category

 Raw waste  load and  the control  and treatment  data indicate that the
 proposed  control and treatment  technologies for  latex  rubber waste-
waters will achieve the  following effluent quality:

               COD                    500 mg/L
               BOD                     25 mg/L
               Suspended  Solids       40 mg/L
               Oil and Grease          10 mg/L

Effluent quality can also be expressed In terms of effluent waste loads,
which are  independent  of wastewater flow.  These effluent waste loads,
resulting from the application  of treatment technologies equivalent to
primary clarification with chemical coagulation followed by biological
treatment, constitute  the best  practicable control and treatment tech-
nology standards currently available  (Level 1) for the latex rubber
sub-category.  Recommendations  for proposed limitations for Level 1
are:
 NOTICE:  THESE ARE TENTATIVE  RECOMMENDATIONS  BASED UPON  INFORMATION
 IN THIS REPORT AND ARE  SUBJECT  TO  CHANGE  BASED  UPON COMMENTS  RECEIVED
 AND  FURTHER  INTERNAL  REVIEW  BY  EPA.
                                IX-9

-------
                                                                    DRAFT
               COD                    6.85  kg/10^  kg  production
               BOD                    0.34  kg/10^  kg  production
               Suspended  Solids       0.55  kg/10^  kg  production
               Oil  and  Grease         0.14  kg/10^  kg  production
NOTICE:  THESE ARE TENTATIVE RECOMMENDATIONS  BASED  UPON  INFORMATION
IN THIS REPORT AND ARE SUBJECT TO  CHANGE  BASED  UPON  COMMENTS  RECEIVED
AND FURTHER INTERNAL REVIEW BY EPA.
                               IX-10

-------
                                                                    DRAFT
                            CHAPTER X

             BEST AVAILABLE TECHNOLOGY ECONOMICALLY
               ACHIEVABLE -- EFFLUENT LIMITATIONS
Tire and Inner Tube Industry

Effluent limitations commensurate with best available technology econom-
ically achievable and best practicable technology currently available
are identical.


          Old Tire and  Inner Tube Production Facilities

        Suspended Solids    0.064 kg/10^  kg raw materials
        Oil and Grease      0.008 kg/10   kg raw materials
                 New Tire  Production  Facilities

        Suspended  Solids     0.064 kg/10^  kg  raw  materials
        Oil  and Grease       0.008 kg/10  kg  raw  materials


 Based on  a  typical  plant  size of  205  metric  tons of  raw materials per
 day, and  process wastewater flow  rate of  3.?85  liters/sec  (60  ppm), a
 loading of  .008  kg/1000 kg raw materials  results in  an  effluent  con-
 centration  of  5 mg/L.

 This concentration of  oil  represents  the  lower  accuracy limit  based on
 currently approved EPA analytical techniques.  Further  reductions would
 therefore be academic,  and cost data  could then  not  be  equated to addi-
 tional  beneficial  reduction.

 A suspended solids loading of .064 kg/1000 kg of raw material  consumed
 is equivalent  to a concentration of 40 mg/L.  This concentration is not
 significant and  will  have minimal impact  on the receiving  stream.
 Further reduction in suspended solids does not appear to be justified
 either  on a cost  or on a benefit basis.
  AND FURTHER  INTERNAL  REVIEW  BY  EPA.
                                 X-l

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                                                                   DRAFT
Synthetic Rubber Industry

     Identification of Best Practical  Control  Technology
     Currently Available

After review of the data and control  and treatment technologies,  it  is
clear the principal pollutant load after biological  treatment,  for all
sub-categories in the Synthetic Rubber Industry waste,  is  due  to  COD.
The other parameters (BOD, suspended  solids, and oil  and grease)  are
reduced to comparatively low levels.   Therefore, advanced  treatment  should
be addressed to COD removal and reduction.

None of the end-of-pipe systems observed in use by this industry  was con-
sidered completely adequate for establishing effluent limitations com-
mensurate with the best available technology economically achievable
(Level  II).

          Emulsion Crumb Sub-category

After biological treatment, emulsion  crumb wastewaters have low BOD,
suspended solids, and oil and grease  concentrations,  and high  COD concen-
trations  (about 500 mg/L).  The most  feasible technique to reduce residual
COD content after biological treatment is by using an activated carbon
adsorption technique.  This technology has been studied in pilot  scale
apparatus using as feed stock emulsion crumb wastewaters which had  been
subjected to secondary treatment.  After treatment with carbon, the
resultant COD level was reduced to about 130 mg/L.  This degree of  removal
has been used to establish Level  I I COD effluent  limitations and standards
of performance for the emulsion crumb sub-category.

Because both the quantity and quality of the data available for supporting
the adoption of this level of treatment for secondary wastewaters from
emussion crumb facilities are sparse, the proposed limitations of perfor-
mance will be confirmed by the EPA National Environmental Research  Center,
Cincinnati, Ohio prior to approval of this document by  the EPA.^  The
technology proposed here  involves no more than  acceptable technical risk
and uncertainty of costs.

Figure X-l shows a hypothetical advanced wastewater treatment  facility using
activated carbon treatment to achieve COD removals adequate for Level  II
control and treatment  technology.

The secondary effluent discharges  into a holding  tank which is normally
maintained full by a  level-control signal to  the  feed pumps.   The feed
pumps produce sufficient  line pressure  to pump  the wastewater  through  the
dual multi-media filters  and the  carbon columns.
NOTICE:  THESE ARE TENTATIVE  RECOMMENDATIONS BASED UPON INFORMATION
 IN THIS  REPORT AND ARE  SUBJECT TO CHANGE BASED UPON COMMENTS  RECEIVED
AND  FURTHER  INTERNAL  REVIEW BY EPA.
                                    X-2

-------
                                                     FIGURE X-l
               HYPOTHETICAL END-OF-PIPE ADVANCED  WASTEWATER TREATMENT FACILITY
                            FOR ALL SUB-CATEGORIES OF SYNTHETIC  RUBBER PLANTS
                                             REGENERATED CARBON
                                MAKEUP CARBON
                                                                 ECU LSI OX CRUMB
                                                                 PLANTS ONLY
                                                                    REGENERATION
                                                                    FURNACE
                                                      CARBON
                                                      CHARGE
                                                      HOPPERS
              BACKWASH TO
              AERATION BASINS
                           BACKWASH TO  «-
                           AERATION BASINS
WASTEWATER
FROM
SECONDARY
TREATMENT
WASTEWATER
HOLDING
TANK
                                                RECHARGE CARBON
DUAL MEDIA
FILTER(S)
                 FEED
                 PUMPS
                                               SPENT CARBON
                                               STORAGE
                                                                  SPENT
                                                                  CARBON
ACTIVATED
CARBON
COLUMNS
                                              FILTER
                                              BACKWASH
BONITORING
STATION
                                     SPENT CARBON
                                   "•"DISPOSAL
                                     (SOLUTION
                                     CRUSB
                                     MO LATEX
                                     PLANTS)
FINAL
DISCHARGE
                                                              COLUMN
                                                              BACKWASH
                       BACKWASH PUMPS

-------
                                                                   DRAFT
The wastewater is first filtered to remove the residual suspended solids
from secondary treatment.  Filtration before the carbon bed will  prevent
fine particles from plugging the carbon.  The filtration media used generally
are anthracite and fine graded sands.  The filters are dual or multiple
units depending on the wastewater flow rate and standard equipment sizes
available.  Periodically, these filters require backv/ashing indicated by
a pressure buildup upstream or a pressure drop across the filter bed.
When filter backwashing is necessary, the feed is switched to the dual
unit, the backwash pumps are activated, and the unit undergoes the complete
backwash cycle.  Backwash water containing trapped solids is piped to the
aeration basins of the secondary treatment facility.  The backwash cycle
usually includes an air scour and a final service flow period for resettle-
ment of the filter media.  The flow rate during the backwash cycle is con-
siderably higher than during the normal service cycle and therefore requires
a holding tank of sufficient capacity to furnish the necessary water for  the
backwash operation.

The filtered wastewater flows down through the activated carbon columns.
Depending on the wastewater flow rate, two or more parallel carbon bed
columns may be required.  Due to solids builup in the carbon columns,
periodic backwashing  is also required.  Each column  is backwashed when the
pressure drop across  the column exceeds a pre-set value.  The backwashing
water is discharged to the aeration basins of the secondary treatment
faci1i ty.

The carbon  in the columns is replaced with fresh or  regenerated carbon
when its activity  is  depleted.  This  is  indicated by breakthrough or
leakage as  detected in an automatic  total carbon analyzer.  The spent
carbon is discharged  to a spent carbon  storage bin,  and  a  regenerated  or
fresh charge of carbon is provided to  the columns from a charge hopper.

The effluent from  the carbon bed columns has  low COD,  BOD,  suspended  solids,
and oil and grease.   The  flow of this  effluent  is monitored  through  a
monitoring  station where  a 24 hour composite  sample  is collected.

In most emulsion crumb plants,  the carbon usage  is  sufficiently  high  to
justify on-site  regeneration.   Regeneration may  be  carried  out  in  an  oil-
fired, multiple-hearth furnace.  The  spent carbon  is continuously  fed  from
the spent carbon storage  bin  to  the  furnace.  The  regenerated and  cooled
carbon Is then  returned  to a carbon  charge hopper and  is ready  for  re-charging.
Overflow  carbon  quench and  slurry waters  from the  regeneration  process are
discharged  to  the  aeration basins of the  secondary  treatment  plant.   Makeup
carbon  (to  replace carbon lost  during unloading,  transfer,  loading,  and
regeneration)  is added at the  charge hopper.   Losses normally amount  to
approximately  5  percent  of  the  regenerated carbon weight.
NOTICE:  THESE ARE TENTATIVE  RECOMMENDATIONS  BASED  UPON  INFORMATION
IN THIS REPORT AND ARE SUBJECT TO CHANGE  BASED  UPON  COMMENTS  RECEIVED
AND FURTHER INTERNAL REVIEW BY EPA.

                                    X-k

-------
                                                                   DRAFT
In smaller emulsion crumb production facilities, carbon usage is low and
on-site regeneration may not be feasible.  The carbon can then either be
returned to the supplier for regeneration or can be disposed of as solid
waste in a landfill site.

          Solution Crumb Sub-Category

The hypothetical advanced wastewater treatment  facility illustrated in
Figure X-1 is also applicable to a secondary effluent from solution crumb
wastewater.  The illustrated facility will produce an effluent satisfactory
for Level  II control and treatment technology.

Although this technology has not been used by plants  in the solution crumb
sub-category, it has been studied for emulsion  crumb  secondary effluent.
Because of the many similarities between  solution  crumb and emulsion crumb
wastewater  (e.g.,  use  of the same monomers and  similar processing techniques
by  the two sub-categories),  it  is reasonable  to propose this advanced treatment
technology  for secondary solution crumb  wastewater.   The  level of treatment
representative of  this technology will be confirmed  by the  EPA National^
Environmental Research Center,  Cincinnati, Ohio prior to  approval of this
document  by  the  EPA.   The  technology  proposed here to achieve  Level  II in-
volves no  more  than acceptable  technical  risk and  cost uncertainty.

The advanced  treatment facility for  solution  crumb is similar  to  that for
emulsion  crumb,  except that  in  most  cases the carbon will  be  disposed of or
regenerated  off-site,  instead  of being  regenerated on-site.   This  is  due
primarily to the fact  that  solution  crumb plants are generally smaller than
emulsion  crumb  plants, and on-site  carbon regeneration is not economically
feasi ble.

           Latex Sub-Category

Again,  the hypothetical advanced wastewater treatment facility illustrated
 in Figure X-1 is recommended for treatment of secondary effluent latex  rubber
wastewaters.  This facility corresponds to the proposed Level II  control  and
 treatment technology  for latex rubber plants.

 This technology has not been used by latex rubber plants, but it has been
 studied, on a pilot scale, for the advanced treatment of secondary ef-
 fluent emulsion crumb rubber wastewaters.  There  are many similarities
 in materails used and processing operations between  latex and emulsion
 crumb production, and hence similarities  in their wastewaters   D.fferences
 tend to revolve around the  level of  loadings rather  than the character.st.es
 and constituents.  It is, therefore, reasonable to  recommend this advanced
 treatment technology  for secondary effluent  latex rubber wastewaters.  The
 level of treatment attainable  by this technology  will be conf,rmed by the
 EPA National Environmental  Research  Center,  Cincinnati,  Oh.o pr.or to ap-
 proval of this  document by  the EPA.  This technology involves no more than
 acceptable  technical  risk and  cost  uncertainty.


  NOTICE-   THESE ARE TENTATIVE RECOMMENDATIONS BASED UPON INFORMATION
  m THIS  REPORT AND ARE SUBJECT TO CHANGE BASED UPON COMMENTS RECEIVED
  AND FURTHER INTERNAL REVIEW BY EPA.

                                     X-5

-------
                                                                   DRAFT
The hypothetical facility will be similar to that proposed for  emulsion
crumb wastewaters.   However, it is most probable (because of unfavorable
economics) that on-site carbon regeneration will not be practiced.   Off-
site regeneration by the carbon supplier or landfill disposal of the ex-
hausted carbon appears more feasible from a technology and cost basis.

     Effluent Loading Attainable with Proposed Technologies

          Emulsion Crumb Sub-category

Based on secondary treatment data and pilot studies of activated carbon
adsorption, the proposed control and treatment technologies will result
in effluent quality better than or equal to the following values:

               COD                   130 mg/L
               BOD                     5 mg/L
               Suspended Solids       10 mg/L
               Oil and Grease          5 mg/L

The proposed treatment will probably produce an effluent of higher quality
for BOD, Suspended Solids, and Oil and Grease than  the above values.  How-
ever, the  resultant limitations on these parameters are governed by the
accuracy of the analytical methods.

Effluent quality can also be defined in  terms of effluent waste  loads,
which are  independent of wastewater flow.  These effluent waste  loads,
resulting  from the application of treatment technologies equivalent to
multi-media filtration and activated carbon adsorption, constitute  the
best available treatment economically achievable  (Level  II) for  the
emulsion crumb sub-category.  The proposed  limitations for  Level II
are as  follows:

               COD                2.08  kg/103 kg production
                BOD                0.08  kg/103 kg production
               Suspended Solids   0.16  kg/103 kg production
               Oil and Grease     0.08  kg/103 kg production

           Solution Crumb Sub-category

 Industry  secondary  treatment  data and  data  extrapolated  from the pilot-
scale  activated  carbon adsorption studies  on  secondary effluent emulsion
crumb  wastewaters were used  to  quantify the effluent  quality of solution
crumb  wastewaters  following  advanced treatment.  The  effluent  quality is
given  as  follows:

                COD                   130 mg/L
                BOD                      5 mg/L
                Suspended  Solids       10 mg/L
                Oil  and  Grease          5 mg/L
 NOTICE:   THESE ARE TENTATIVE RECOMMENDATIONS BASED UPON INFORMATION
 IN THIS  REPORT AND ARE SUBJECT TO CHANGE BASED UPON COMMENTS RECEIVED
 AND FURTHER INTERNAL REVIEW BY EPA.

                                    X-6

-------
                                                                   DRAFT
The effluent values for BOD, Suspended Solids, and Oil and Grease are
dictated by the lower  limit of accuracy for the currently accepted
analytical methods.

Effluent quality can also be expressed in terms of effluent waste loads,
which are independent of wastewater flow.  The effluent waste loads fol-
lowing multi-media filtration and activated carbon adsorption constitute
the best available treatment economically achievable  (Level II)  for the
solution crumb sub-category.  The proposed limitations for Level  II are
as follows:

               COD                   2.08 kg/103 kg production
               BOD                   0.08 kg/103 kg production
               Suspended Solids      0.16 kg/103 kg production
               Oil and Grease        0.08 kg/103 kg production

          Latex Sub-category

Latex industry secondary treatment data and data extrapolated from pilot-
scale plant  studies on the activated carbon adsorption treatment of emulsion
crumb secondary effluent were used to formulate the following effluent
qual i ties:

               COD                   130 mg/L
               BOD                     5 mg/L
               Suspended Solids       10 mg/L
               Oil and Grease          5
The effluent levels for BOD, Suspended Solids, and Oil and Grease are
dependent on the accuracy of the best accepted analytical methods.

Effluent quality can also be expressed in terms of effluent waste loads
which are independent of wastewater flow.  The effluent waste loads re-
sulting from the application of treatment technologies equivalent to multi
media filtration and activated carbon adsorption form the basis for the
best available treatment economically available (Level II) for the latex
sub-category.  The proposed limitations for Level  II are:

               COD                   1.78 kg/103 kg production
               BOD                   0.07 kg/103 kg production
               Suspended Solids      O.lA kg/103 kg production
               Oil and Grease        0.07 kg/103 kg production
NOTICE:  THESE ARE TENTATIVE  RECOMMENDATIONS  BASED UPON  INFORMATION
IN THIS REPORT AND ARE  SUBJECT  TO  CHANGE  BASED  UPON COMMENTS  RECEIVED
AND FURTHER  INTERNAL  REVIEW  BY  EPA.

                                   X-7

-------
                                                                    DRAFT
                           SECTION XI

                NEW-SOURCE PERFORMANCE STANDARDS
Tire and Inner Tube Production Facilities

Recommended effluent limitations for new sources are identical  and com-
mensurate with best available technology economically achievable and
best practicable technology currently available.  These effluent limita-
tions are presented in Sections IX and X of this report.

Synthetic Rubber Industry

Because all stated sub-categories of the synthetic rubber industry are
highly technical and involve proprietary processes, in-plant control
technologies cannot be fully defined or enumerated; such in-plant
measures might impact on manufacturing practices and product quality.

Since advanced wastewater treatment technologies have been proposed for
the best available end-of-pipe treatment economically achievable by
existing plants, no improvement upon those standards can be recommended
for new sources.  No additional treatment technologies or controls are
proposed for beyond Level II.   It should be noted at this time that the
application of activated carbon adsorption for COD removal after second-
ary treatment involves acceptable but certain technical risks and
unconfirmed costs.  The performance of this proposed advanced treatment
technology will be confirmed by the EPA National Environmental Research
Center, Cincinnati, Ohio, prior to approval of this document by EPA.

The effluent waste loads resulting from the application of the best
available treatment economically achievable for new sources (Level  III)
for synthetic rubber plants are as follows:
     Emulsion Crumb Sub-category

          COD                        2.08  kg/10;
          BOD                        0.08  kg/10;
          Suspended Solids           0.16  kg/10;
          Oil and Grease             0.08  kg/10'

     Solution Crumb Sub-category

          COD                        2.08  kg/10:
          BOD                        0.08  kg/10:
          Suspended Solids           0.16  kg/10:
          Oil and Grease             0.08  kg/10'
                                        kg
                                        kg
                                        kg
                                        kg
                                        kg
                                        kg
                                        kg
                                        kg
product ion
production
production
production
production
production
production
production
 NOTICE
 IN THIS
 AND FURTHER
 THESE ARE TENTATIVE RECOMMENDATIONS BASED UPON INFORMATION
REPORT AND ARE SUBJECT TO CHANGE BASED UPON COMMENTS RECEIVED
    INTERNAL REVIEW BY EPA.
                              Xl-l

-------
                                                                  DRAFT
    Latex Sub-category

        COD                         K78  kg/10^  kg production
        BOD                         0.07  kg/10^  kg production
        Suspended  Sol ids            0.14  kg/10^  kg production
        Oil  and  Grease              0.07  kg/10   kg production

Pretreatment Recommendations

A minimum level of pretreatment must be given to new production facilities
which will discharge wastewater to a publicly owned treatment works.   In
addition, potential pollutants which will inhibit or upset the performance
of  publicly owned  treatment works  must be eliminated from such discharges.

     Tire and  Inner Tube  Industry

Pretreatment recommendations for process wastewaters from the tire and
inner tube industry include the separation of oils and solids in an API
gravity separator  and the use of an equalization basin to prevent shock
loads of oi 1, suspended solids or batch dumps of dipping solutions from
entering and upsetting the performance of a publically owned treatment
works.  Oily wastes, after dilution in a public sewer system,will remain
untreated and  therefore must be controlled before discharge from the
plant boundaries.

Pretreatment of other non-process wastewaters from the tire and  inner
tube industry  will pose more difficult problems.  These include alkalinity
in  boiler blowdowns and both acidity and alkalinity in water treatment
wastes.  Both boiler blowdowns and water treatment wastes will contain
high concentrations of suspended and dissolved  solids.  Cooling  tower
water treatment wastes may contain  heavy metals such as chromium and
zinc used for  corrosion inhibition.  Potential  problems such as acidity,
alkalinity,  solids, oils, and heavy metals may  require control at the
plant to conform to local ordinances for discharge to a publicly owned
treatment works.   The control techniques and treatment methods are de-
scribed in earlier sections of this report.  Equalization of the waste
load and wastewater flow  is the key step in the control of batch dumps
of  production  chemicals and solutions.

     Synthetic Rubber Industry

Emulsion crumb and solution crumb slurry overflow wastewaters should be
passed through crumb pits to remove floatable rubber crumb.  Few pub-
licly owned  treatment works have primary clarification equipment ade-
quate to handle  large quantities of agglomerated rubber crumb solids.

Wastewaters  from emulsion crumb and latex production facilities  are
invariably laden with uncoagu-lated  latex solids.  Since publicly owned
treatment works  do not generally have coagulation capabilities,  these
wastewaters  should, at least, be chemical coagulated with a  sinking
agent and clarified.
NOTICE-   THESE ARE TENTATIVE RECOMMENDATIONS BASED UPON INFORMATION
IN THIS  REPORT AND ARE SUBJECT TO CHANGE BASED UPON COMMENTS RECEIVED
AND FURTHER INTERNAL REVIEW BY EPA.
                            XI-2

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                                                                  DRAFT
Utility wastes often exhibit extreme pH peaks which should  be  neutra-
lized or, at least equalized, prior to discharge to the  publicly owned
treatment works.  This problem is not so severe with emulsion  crumb
and latex plants, where pH adjustment is required prior  to  chemical
coagulation, as it is with solution crumb production facilities where
adjustment of the wastewater pH is normally not necessary.   Heavy
metals, present in cooling tower blowdowns for example,  should be
eliminated by substitution of inhibitor or equalized prior  to  discharge
to a publicly owned treatment works.

No compounds or species present in synthetic rubber wastewater can be
considered toxic or inhibitory to the performance of publicly owned
treatment works.

In summary, the following pretreatment  requirements apply to wastewater
discharges to publicly owned treatment  works from synthetic rubber
plants:

     Emulsion Crumb Subcategory - Gravity separation of crumb  fines
     in crumb pits, chemical coagulation and clarification of  latex-
     laden wastewaters, and  neutralization or equalization of  utility
     wastes.

     Solution Crumb Subcategory - Gravity separation of crumb^fines
     in  crumb pits, and neutralization  or equalization of utility
     wastes.
      Latex  Subcateqory  -  Chemical  coagulation of  latex-laden waste-
      waters,  and  neutralization  or equalization of  utility wastes.
 NOTICE-  THESE ARE TENTATIVE RECOMMENDATIONS BASED UPON  INFORMATION
 m THIS REPORT AND ARE SUBJECT TO CHANGE BASED UPON COMMENTS RECEIVED
 AND FURTHER  INTERNAL REVIEW BY EPA.

                                XI - 3

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                                                                     DRAFT
                               SECTION XII

                            ACKNOWLEDGEMENTS
Roy F.  Western, Inc. wishes to express appreciation to the Rubber
Manufacturers Association (RMA) and its Environment Committee.   RMA
and the RMA Environment Conmittee (Daniel G. Pennington,  Secretary)
provided valuable assistance in the selection of representative process
plants within the  rubber processing industry.

Roy F.  Weston, Inc. also acknowledges the assistance of the personnel
at the EPA Regional Centers who were contacted to obtain assistance
in identifying plants in the rubber processing industry known to be
achieving effective waste treatment.  Special mention should be given  Messrs
Herbert S. Skovronek, John Lank, Paul Ambrose, and Marshall Dick.

Acknowledgement is made of the cooperation of industry personnel in  many
plants in the rubber processing industry who provided valuable assistance
in the collection of data relating to process RWL and treatment plant
performance.  Special acknowledgement  is made of those plant personnel^
and company officers who cooperated  in providing detailed plant operating
data to support this study.

Acknowledgement is made also of the assistance and direction provided
by the Project Officer, Mr.  John E.  Riley,  and others associated with
the Effluent  Guidelines Division:  Messrs.  Allen Cywin,  Ernest  P. Hall,
Walter Hunt,  and others who  provided helpful suggestions and comments.
                                 XI 1-1

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                                                                     DRAFT
                              SECTION XI I I

                               REFERENCES


1.   Shreve,  R.N.,  Chemical  Process Industries.  CPI;  McGraw Hill,  Inc.,
    New York,  (19&7).

2.   Standen, A.,  ed.,  Kirk-Othmer. Encyclopedia of Chemical  Technology;
    Vol. 17, John Wiley and Sons, New York, (1968).

3.   Kestein, B.,  "SBR and Polybutadiene Rubbers," Symposium on Tire
    Material Decisions, AICHE 7^rd National Meeting, Minneapolis,  Minnesota,
    (August 29, 1972).

k.   "Rubber Industry Facts", Rubber Manufacturers Association, New York,
    1972.

5.   Private Communications from  Chem Systems,  Inc., New York.

6.   "Air Flotation-Biological Oxidation of Synthetic Rubber and Latex
    Wastewater", Firestone Synthetic Rubber and Latex Company, Lake
    Charles, Louisiana  (October  15,  1972).

7   "Industrial Wastewater Reclamation with JtOO.OOO-gal lon-per-day Vertical
    Tube Evaporator,  Design,  Construction  and  Initial Operation", The
    General Tire and  Rubber  Company, Akron, Ohio  (September,  1972).

                           GENERAL BIBLIOGRAPHY


Rostenbach,  R.E.,  "Status  Report on  Synthetic  Rubber Wastes  "Sewage
and  Industrial Waste.  Vol.  2k;  No. 9,  (September  1952),  1138-1 U»3.

Placek,  O.R. and  Ruchhoft,  C.C., "A  Study  of Wastes from the Synthetic
Rubber Industry."   Sewage  and Industrial Waste.  Vol.  18, No.  6,
 (November  19^6),  1160-1181.

Martin,  A.E. and  Rostenbach, R.E.,  "Industrial Waste Treatment and
Disposal."  Industrial and Engineering Chemistry. Vol.  ^5,  No. 1Z,
 (December  1953),  2680-2685.

 "Putting the Closed Loop into Practice."  Environmental Science and
Technology. Vol.  6, No. 13,  (December 1972),  1072-1073.
                                XIM-1

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                                                                     DRAFT
Dougan, L.D. and Bell, J.C., "Waste Disposal at a Synthetic Rubber
Plant."  Sewage and Industrial Wastes. Vol. 23, No. 2, (February 1951),
181-187.

"A Study of Pollution Control Practices in Manufacturing Industries."
Marketing Services Division, Research Services Department,  Dun and
Bradstreet, Inc., (June 1970.

Hebbard, G.M., Powell, S.T. and Rostenbach, R.E., "Rubber Industry."
Industrial and Engineering Chemistry, Vol. 39, No. 5,  (May 19^7), 589-595.

Ne-nerow, N.L., Theories and Practices of  Industrial Waste Treatment,
Addison-Wesley Publishing Co., New York,(1963).

Alliger, G. and Weissert, F.C., "Elastomers."  Industrial and Engineering
Chemistry. Vol. 59, No. 8, (August 1967), 80-90.

Herzlich, H.J., "Tire Compounding."  Chemical  Engineering Progress,
Vol.  69, No. 2,  (February' 1973), 77-?8.

Montgomery, D.R., "Integrated System for  Plant Wastes Combats Stream
Pollution."  Chemica1 Engi neer ing, Vol. 63, No. 4, (February 19&7),
108-110.

Ruebensaal, C.F., "The Rubber  Industry Statistical Report and Changing
Markets and Manufacturing Patterns in the Synthetic Rubber  Industry."
International  Institute of Synthetic Rubber Producers,  Inc., New York,
(1972).

Anderson, E.V., "Rubber, A $16 Billion  Industry Turns on Tires."
Chemical and Engineering  News, (July \k,  19&9), 39-83.

Hofmann, W., Vulcanization and Vulcanizing Agents; Palmerton Publishing
Co.,  Inc.,  New York,  (1967).

Hawley, G.G., The Condensed Chemical Dictionary,  Reinhold Co.,  New York,
(1970.

Fawcett, R.J. and McDone, E.T., "Special  Rubbers  in Tires."  Symposium
on Tire Material Decisions, AICHE 73rd  National Meeting, Minneapolis,
Minnesota,  (August 29, 1972).

Lund, H.F., ed.,  Industrial Pollution Control  Handbook; McGraw-Hill,  Inc.,
New York, (1971).
                                 XIM-2

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                                                                     DRAFT
"Methods for Chemical Analysis of Water and Wastes."  Environmental  Pro-
tection Agency, National Environmental Research Center, Analytical  Quality
Control Laboratory, Cincinnati, Ohio, (1971),

Taras, M.J., ed. , Standard Methods for the Examination of Water and
Wastewater.  American Public Health Association, Washington, D.C.,  (1971).

Water; Atmospheric Analysis, Part 23, "Standard Method of Test for  Bio-
chemical Oxygen Demand of  Industrial Water and  Industrial Wastewater."
1970 Annual Book of ASTM Standards, American Society for Testing and
Materials, Philadelphia, Pennsylvania, (1970).

Eckenfelder, W.W., Industrial Water Pollution Control; McGraw-Hill,  Inc.,
New York,  (1966).

Perry, J.H., ed., Chemical Engineers' Handbook, 4th Ed.; McGraw-Hill,  Inc.,
New York,  (1963).
                                    XIII-3

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                                                                      DRAFT

                               SECTION XIV

                                GLOSSARY


 Act

 The  Federal Water  Pollution  Control Act Amendments of 1972.

 Act i va to r

 A metallic oxide that makes  possible  the  crosslinking of sulfur
 in  rubber vulcanization.

 Antioxidant

 An organic compound added  to rubber to  retard oxidation or deterioration.

 Accelerator Agents

 A compound which greatly  reduces  the  time  required for vulcanization of
 synthetic or natural rubber.

 Banbury Mixer

 Trade name for a common  internal  mixer manufactured by Farrel Corporation
 used in the compounding and  mixing of tire  rubber stock.

.Best Available Technology  Economically Achievable (BATEA)

 Treatment required by July 1,  1983 for  industrial discharges to surface
 waters as defined by Section 301  (b)  (2)  (A) of the Act.

 Best Practicable Control Technology Currently Available  (BPCTCA)

 Treatment required by July 1,  1977 for  industrial discharges to surface
waters as defined by Section 301  (b)  (1)  (A) of the Act.

 Best Available Demonstrated  Control Technology  (BADCT)

Treatment required for new sources as defined by Section 306 of the Act.

 BOD

 Biochemical  Oxygen Demand.

Bag House

An air emission control  device used to collect intermediate and large
particles (greater than  20 microns) in a bag filter.   A bag filter is con-
structed of fabric.  Common usage in the tire industry is to control  and
 recover carbon black in  a dry state from vapors leaving the compounding area.
                                XIV-1

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                                                                      DRAFT
Butyl Rubber

A synthetic rubber made by the solution polymerization of isobutylene
and  isoprene.

Camelback

Tire tread used in the retreading of tire carcasses.

Capital Costs

Financial charges in August 1971 dollars which are computed as the cost
of capital times the capital expenditures for pollution control.   Cost
of capital is assumed to be 10 percent.

Carbon Black

A  reinforcing agent used in large quantities in tire  rubber compounds.

Catalyst

A  substance that initiates a chemical  reaction and enables it to proceed
at a greatly accelerated  rate.

Category and Subcategory

Divisions of a  particular  industry which possess different traits which
affect water quality and treatabi1ity.

Cement

A  solution of synthetic  rubber  particles.

Chain

A  revolving metal belt upon which  the  newly  formed  glass  fibers fall
to form  a  thick mat.  There are two  general  types of  chains:  wire
mesh chains and light conveyors.   The  latter are hinged metal plates
with several holes  to  facilitate the passage of air.

Coagulation

The combination or  aggregation  of  previously emulsified  rubber particles
 into a clot or  mass.

COD

 Chemical  Oxygen Demand.
                                  XIV-2

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                                                                      DRAFT
C rumb

Small coagulated particles of synthetic rubber.

Curing Agent

Curing or vulcanization agents are substances which bring  about  the
rubber crosslinking process.  The most important agent  is  sulfur.  See
vulcanizat ion.

Depreciation

Accounting charges reflecting the deterioration of a capital  asset over
its useful life.  Reported as straight line over five years with zero
salvage value.

Dry Air Pollution Control

The technique of air pollution abatement without the use of water.

Emulsi on

A stable mixture of two or more immersible liquids held in suspension  by
small percentage of substances called emulsifiers.

Endogenous Respiration

Auto-oxidation of the microorganisms producing a reduction and stabilization
of biological solids.

EPDH

A synthetic rubber based on ethylene-propylene and a controlled amount of
non-conjugated diene.  Polymerization is carried out in solution.

Extender
A low specific gravity substance used in rubber formulations chiefly to
reduce costs.

Extrude
To shape by forcing a material through a die.  The operation is carried
out in a device known as an extruder.  In tire and inner tube manufacture
treads and inner tubes are formed by extrusion.
                                   XIV-3

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                                                                    DRAFT
Filler

A high specific gravity (2.00-^.50) compound  used  in  rubber mixtures to
provide a certain degree of stiffness and hardness  and  used to decrease
costs.  Fillers have neither reinforcing or coloring  properties and are
similar to extenders in their cost-reducing function.

qpm

Gallons per minute.
Polyisoprene rubber, the major component of natural  rubber,  made  syn-
thetically by the solution polymerization of isoprene.

Investment Costs
The capital  expenditures reported in August 1971  dollars  required  to  bring
the treatment or control technology into operation.   Included  are
expenditures for design, site preparation, purchase of materials,  con-
struction and installation.  Not included is the purchase of land  on
which the system is to be built.
Liter

Latex

A suspension of rubber particles In a water solution.   Coagulation of
the rubber is prevented by protective colloids.  A colloid is a surface
active substance that prevents a dispersed phase of a suspension from
coalescing by forming a thin layer on the surface of each particle.

Masterbatch

A compounded rubber stock applicable to a wide variety of uses.  Main
ingredients are rubber, carbon black and extender oil.

mq/1

Milligrams per liter.  Nearly equivalent to parts per million concentration.

Mod? fier

An additive which adjusts the chain length and molecular weight dis-
tribution of the rubber during polymerization.

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                                                                      DRAFT
Honome r

A compound of a relatively low molecular weight which  is  capable of
conversion to polymers or other compounds.

NJ3R

Nitrite rubber, a synthetic rubber made by  emulsion polymerization of
acrylonitrile with butadiene.

New Source

Any building, structure, facility, or installation from which there  is
or may be a discharge of pollutants and whose construction is commenced
after the publication of the proposed regulations.

Non-Productive Rubber Stock

Rubber stock which has been compounded but  which contains no curing  agents.
Synonym for non-reactive rubber stock.

Non-Reactive Rubber Stock

Rubber stock which has been compounded but  which contains no curing
agents.  Synonym for non-productive  rubber stock.

Operations and Maintenance

Costs  required to operate and maintain pollution abatement equipment.
They  include labor, material, insurance, taxes, solid waste disposal,  etc.

PBR

Polybutadiene  rubber, a synthetic  rubber made  by  solution polymerization
of butadiene.

jjH

A measure  of the  relative acidity  or alkalinity of water.  A pH of 7.0
indicates  a neutral condition.  A  greater pH  indicates alkalinity and
a lower pH indicates acidity.  A one unit change  in pH indicates a 10
fold  change  In acidity and alkalinity.

Pigment

Any substance  that  imparts color  to  the  rubber.   Pigment  substances such
as zinc oxide  or  carbon black also act as  reinforcing agents.
                              XIV-5

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                                                                     DRAFT
Plastic

Capable of being shaped or molded with or without  the application of heat.

Process Water

AH waters that come into direct contact with  the  raw mater ials,  inter-
mediate products, final products, or contaminated  waters  or  air.

Productive Rubber Stock

Compounded rubber which contains curing agents and which  can be  vulcan-
ized.  Synonym for reactive rubber stock.

Reactive Rubber Stock

Compounded rubber which contains curing agents and which  can be  vulcan-
ized.  Synonym for productive rubber stock.

Reinforcers or Reinforcing Agent

Fine powders used to increase the strength, hardness and  abrasion
resistance of  rubber.  Reinforcing agents used in the rubber processing
include carbon black, zinc oxide and hydrated silicas.
Styrene Butadiene Rubber, a synthetic rubber made either by emulsion or
solution polymerization of styrene and butadiene.
Soapstone
A  substance used to prevent tire and  inner tube rubber stocks from sticking
together during periods of storage.   Used in both a dry and solution form.
The major  ingredient  is usually clay.

Solution

A  uniformly dispersed mixture of the  molecular level of one or more
substances in one or more other substances.

_St ripper

A  device  in which relatively volatile components are removed from a mixture
by distillation or by passage of steam  through the mixture.
                           XIV-6

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                                                                      DRAFT
 Surface Waters

 Navigable waters.  The waters of  the United States including the
 territorial seas.

 Tire  Bead

 Tire  beads are coated wires  inserted in the pneumatic tire at the point where
 the tire meets the steel  rim on which it is mounted.   They insure an air
 tight seal between the tire and rim.

 Tire  Cord

 Woven synthetic or natural fabrics  impregnated with rubber.  They form the
 body of the tire and supply  it with most of its strength.

 T i re T read

 Tire tread is riding surface of the tire.   Their design and composition
 are dependent on the end use of the tire.

 Vulcanization
Vulcanization is the process by which plastic rubber is converted into the
elastic rubber or hard rubber state.  The process is brought about by linking
of macro-molecules at their reactive sites.

Wet Air Pollution Control

The technique of air pollution abatement utilizing water as an
absorptive media.
                            XIV-7

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                                                                                                             DRAFT
    Enqlish Unit
                                                   SECTION XV

                                       METRIC UNITS AND CONVERSION FACTORS
                            Abbreviation
                                                 Conversion Factor by
                                                                                Metric Unit
                                                                                                        Abbrevi at ion
•ere
acre - feet
cubic feet
cubic feet
cubic inches
cubic yards
feet
gal Ion
gal Ion /mi nute
horsepower
inches
pounds
million gallons/day
square feet
square inches
tons (short) (2,000 Ibs)
tons (long) (2,2
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