EPA 440/l-74/035
Development Document for
Proposed Effluent Limitations Guidelines
and New Source Performance Standards
for the
TEXTILE, FRICTION MATERIALS
AND SEALING DEVICES
Segment of the
ASBESTOS MANUFACTURING
Point Source Category
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
AUGUST 1974
-------
DEVELOPMENT DOCUMENT
for
PROPOSED EFFLUENT LIMITATIONS GUIDELINES
and
NEW SOURCE PERFORMANCE STANDARDS
for the
TEXTILE, FRICTION MATERIALS AND SEALING DEVICES
SEGMENT OF THE
ASBESTOS MANUFACTURING POINT SOURCE CATEGORY
Russell E. Train
Administrator
James L. Agee
Assistant Administrator for Water and
Hazardous Materials
_ito •'«*.
Allen Cywin
Director, Effluent Guidelines Division
Richard T. Gregg
Project Officer
August, 1974
Effluent Guidelines Division
Office of Water and Hazardous Materials
U. S. Environmental Protection Agency
Washington, D. C. 20460
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ABSTRACT
This document presents the findings of an extensive study of part of
the asbestos manufacturing industry by the Environmental Protection
Agency for the purpose of developing effluent limitations guidelines
and Federal standards of performance, for the industry, to implement
Sections 304, 306, and 307 of the "Act."
Effluent limitations 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 that 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 a portion of the asbestos manufacturing category in which water
usage is limited. This segment was subdivided into four subcate-
gories on the bases of raw waste loads, quantities of waste water
discharged, and applicability of control measures. Separate
effluent limitations were developed for each subcategory on the
bases of the level of raw waste loads as well as the degree of
treatment achievable by suggested model systems. These systems
include sedimentation (with coagulation, as necessary), neutrali-
zation, biological treatment, carbon adsorption, substitution of dry
air pollution control equipment, and certain in-plant changes.
Supportive data and rationale for development of the proposed
effluent limitations guidelines and standards of performance are
contained in this report.
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TABLE OF CONTENTS
SECTION
I Conclusions
II Recommendations
III Introduction
Purpose and Authority ^
Summary of Methods °
General Description of the Industry B
Location of Manufacturers j^
Manufacturing Processes ^
Textile Products ^
Friction Materials
Gaskets, Packing, and Sealing Devices 23
Current Status of the Industry 24
IV Industry Categorization 25
Introduction and Conclusions 25
Factors Considered 25
V Water Use and Waste Characterization 29
Textile Coating 29
Solvent Recovery 30
Vapor Absorption 31
Wet Dust Collection 31
Dispersion Process 32
Plant Descriptions 32
VI Selection of Pollutant Parameters 37
Major Pollutants 37
Other Pollutants 39
VII Control and Treatment Technology 47
Introduction ^7
In-Plant Control Measures 48
Treatment Technology 49
Industry Suhcategories 50
iii
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SECTION PAGE
VIII Cost, Energy, and Non-Water Quality Aspects 53
Representative Plants 53
Cost Information 55
Control Technologies with Costs ^6
Energy Requirements of Control Technologies "•*•
Non-Water Quality Aspects of Control
Technologies 65
IX Effluent Reduction Attainable Through 67
Application of the Best Practicable Control
Technology Currently Available - Effluent
Limitations Guidelines
Introduction 67
Effluent Reduction Attainable Through
the Application of Best Practicable
Control Technology Currently Available 67
Identification of Best Practicable
Control Technology Currently Available ^9
Rationale for the Selection of Best
Practicable Control Technology
Currently Available 7^
X Effluent Reduction Attainable Through 73
Application of the Best Available
Technology Economically Achievable -
Effluent Limitations Guidelines
Introduction 73
Effluent Reduction Attainable Through
Application of the Best Available
Technology Economically Achievable 73
Identification of Best Available
Technology Economically Achievable
Rationale for the Selection of Best
Available Technology Economically
Achievable 76
XI New Source Performance Standards 79
Introduction 79
Effluent Quality Achieved Through
Implementation of New Source Performance
Standards 79
Identification of New Source Performance
Standards 79
IV
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SECTION
XII Acknowledgments 83
XIII References 85
XIV Glossary 89
Conversion Table 91
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FIGURES
NUMEER PAGE
1 As"bestos Textiles Manufacturing Operations 16
2 Dry-Mixed Molded Brake Linings Manufacturing
Operations ]_g
3 Wet-Mixed Molded Brake Linings Manufacturing
Operations 20
^ Molded Clutch Facings Manufacturing Operations 21
5 Woven Clutch Facings Manufacturing Operations 22
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TABLES
PAGE
NUMBER
1 Locations of Asbestos Manufacturing Plants - ^
Phase II
2 General Description of Known Waste Water
Sources Asbestos Manufacturing Plants -
Phase II
3 Representative Manufacturing Plants Used in
Developing Cost Estimates
U Water Effluent Treatment Costs - Asbestos ^
Textile Coating
5 Water Effluent Treatment Costs - Solvent
' Do
Recovery
6 Water Effluent Treatment Costs - Vapor
Absorption
7 Water Effluent Treatment Costs - Wet Dust
Collection - Small Plant
8 Water Effluent Treatment Costs - Wet Dust
Collection - Medium Plant
9 Water Effluent Treatment Costs - Wet Dust ^
Collection - Large Plant
10 Effluent Reduction Attainable Through
Application of Best Practicable Control
Technology Currently Available
11 Effluent Reduction Attainable Through
Application of Best Available Technology
Economically Achievable 74
12 Standards of Performance for New Sources 80
vii
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SECTION I
CONCLUSIONS
That part of the asbestos industry covered in this document (Phase
II) includes the manufacture of asbestos textiles, friction mate-
rials, and asbestos gaskets, packings, and sealing devices. In most
of the plants in this part of the industry, water is not used in the
manufacturing processes and waste waters are not generated. In a
few plants, process-related waste waters are generated by
manufacturing operations or by air pollution control equipment. The
industry covered in this document is classified into four
subcategories. The factors in this subcategorization were raw waste
loads, volumes and rates of discharge of waste waters, and
differences in applicable in-plant control measures and end-of-pipe
treatment technologies.
The subcategories are for the following operations:
1. coating, or finishing, of asbestos textiles,
2. Solvent recovery,
3. Vapor absorption, and
4. Wet dust collection.
The waste waters resulting from the first three subcategories are
similar in that the primary pollutants are synthetic organic resins,
elastomers, and/or solvents, but they differ in composition and
concentration. The wastes from the wet dust collectors are
characterized by high suspended solids levels. For all sub-
categories, the volume and strength of the waste waters are
independent of the level of production in the manufacturing plant,
and raw waste loads and effluent limitations guidelines cannot be
meaningfully expressed in terms of production units.
About half of the plants that generate waste waters discharge to
municipal sewerage systems, with or without pretreatment. The
remaining plants provide at least lagoon sedimentation prior to
discharge to surface waters. None of the plants included in this
study provide treatment designed to remove dissolved organic
pollutants.
Recommended effluent limitations to be achieved by July 1, 1977, and
July 1, 1983, are summarized in Section II. It is estimated that
the investment cost of achieving the 1977 limitations and standards
by all plants in the industry is approximately $200,000, excluding
costs of additional land acquisition. The cost of achieving the
1983 level is estimated to be less than $800,000 for the industry,
i.e., an additional $600,000 over the 1977 level.
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SECTION II
RECOMMENDATIONS
Recommended control and treatment technologies for this part of the
asbestos industry were developed for each subcategory. The
discharge of pollutants from asbestos textile coating to surface
waters can be eliminated through in-plant measures; i.e., elimi-
nation of dumps and spills and substitution of dry cleaning
techniques for wet clean-up methods. The discharge of organic
pollutants from solvent recovery and vapor absorption operations can
be reduced or eliminated by biological treatment, carbon adsorption,
and/or substitution of dry air pollution control equipment. The
discharge of suspended solids from wet particulate collectors can be
controlled by sedimentation and eliminated by substituting dry dust
collection devices for the wet scrubbers.
The recommended effluent limitations for parameters of major
significance and standards of performance for plants within the four
subcategories are summarized as follows:
Best Practicable Control Technploqy Currently Available
COD-mg/1
Suspended Solids-
mg/1
pH-units
Textile
Coating
zero
zero
Solvent Vapor
Recovery Absorption
Wet Dust
50
30
6-9
zero
zero
6-9
NA*
30
6-9
Best Available Technology EconomicallY Achievable
COD-mg/1
Suspended Solids-
mg/1
pH-units
Textile
Coating
zero
zero
Solvent Vapor
Recovery. AbsorjDtion
5 zero
5 zero
6-9
Wet Dust
Collection
zero
zero
Standards of Performance for^New sources
Solvent Vapor
COD-mg/1
Suspended Solids-
mg/1
pH-units
Textile
Coating
zero
zero
50
30
6-9
zero
zero
Wet Dust
Collection
zero
zero
*NA - Not Applicable
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SECTION III
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
identified by the Administrator pursuant to Section 304 (b) of the
Act. 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 regulation issued by the Administrator pursuant to
Section 304(b) of the Act. Section 306 of the Act requires the
achievement by new sources of a Federal standard of performance pro-
viding for the control of the discharge of pollutants which reflects
the greatest degree of effluent reduction which the Administration
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.
Section 304(b) of the Act requires the Administrator to publish
within one year of enactment of the Act, regulations providing
guidelines for effluent limitations setting 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
control measures and practices economically achievable including
treatment techniques, process and procedure innovations, operation
methods and other alternatives. The regulations proposed herein set
forth effluent limitations guidelines pursuant to Section 304(b) of
the Act for certain subcategories of the asbestos manufacturing
source category, relating to textiles, friction materials, and
sealant devices. They include coating of textile products, solvent
recovery, vapor absorption, and wet dust collection.
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 performance for new sources within
such categories. The Administrator published in the Federal
Register of January 16, 1973 (38 F.R. 1624), a list of 27 source
categories. Publication of the list constituted announcement of the
Administrator's intention of establishing, under Section 306,
standards of performance applicable to new sources within the
asbestos manufacturing industry subcategory as delineated above,
which was included with the list published January 16, 1973.
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SUMMARY OF METHODS USED FOR DEVELOPMENT OF THE EFFLUENT LIMITATIONS
GUIDELINES AND STANDARDS OF PERFORMANCE
Sse and Authority
The effluent limitations guidelines and standards of performance
proposed herein were developed in the following manner. The point
source category was first categorized for the purpose of determining
whether separate limitations and standards are appropriate for
different segments within a point source category. Such subcate-
gorization was based upon raw material used, product produced,
manufacturing process employed, and other factors. The raw waste
characteristics for each subcategory were then identified. This
included an analysis of (1) the source and volume of water used in
the process employed and the sources of waste and waste water in the
plant; and (2) the constituents (including thermal) of all waste
waters; including toxic constituents and other constituents which
result in taste, odor, and color in water or aquatic organisms. The
constituents of waste waters 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 included an identification of
each distinct control and treatment technology, including both in-
plant and end-of-rprocess 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) and the chemical, physical, and biological characteristics
of pollutants, of the effluent level resulting from the application
of each of the treatment and control technologies. The problems,
limitations and reliability of each treatment and control technology
and the required implementation time was 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 were also
identified. The energy requirements of each of the control and
treatment technologies was identified as well as the cost of the
application of such technologies.
The information, as outlined above, was then evaluated in order to
determine what levels of technology constituted the "best
practicable control technology currently available," "best available
technology economically achievable," and the "best available
demonstrated control technology, processes, operating methods, or
other alternatives." 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 techniques
process changes, non-water quality environmental impact (including
energy requirements) and other factors.
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Sources of Data
The waste waters associated with asbestos manufacturing have
received almost no attention in the engineering and pollution
control literature. Very few plants have collected any extensive
data about the characteristics of the waste waters discharged. The
information used in this document was derived from a number of
sources. Some of the sources were published literature on manu-
facturing methods, EPA technical reports on the industry, and
consultation with qualified personnel. Additional information was
obtained from plant visits; plant records, where available; and from
the few RAPP applications that have been filed. Most of the
information was developed through direct contact by the EPA
contractor, with some additional material derived from a preliminary
questionnaire distributed to its membership by the Fluid Sealing
Association (formerly the Mechanical Packing Association).
Thirty-six companies or corporations at 51 plant locations in the
United States provided information for this document. Another
thirteen companies, exclusive of those receiving the questionnaire
distributed by FSA, were contacted and found not to be manufacturers
of products covered by this study. The 36 companies include most of
the large- and medium-sized manufacturers and what is believed to be
a representative cross-section of the small organizations.
The products covered by this study can be grouped into three types
as shown below. The 51 plants included in this study are dis-
tributed among the product types as follows:
Asbestos Textile Products 10 plants
Friction Materials 25
Asbestos-Containing Gaskets,
Packings, and Sealing Devices 11
Multi-Products Plants 5
At three of the multi-product plants, two Phase II product types are
manufactured. All three Phase II product types are made at two
plants. In addition, at ten of the 51 plants, non-Phase II products
are also manufactured. At three of these locations, the other prod-
ucts are asbestos items covered in the Phase I study. At the
remaining seven plants, non-asbestos product manufacturing generates
waste waters that are much more significant in terms of quantities
and types of pollutant constituents. The wastes from asbestos manu-
facturing are combined with these stronger wastes for treatment
and/or discharge. The combined effluents should be regulated by the
guidelines developed for the other non-asbestos products.
As noted above, a voluntary questionnaire was distributed to those
members of the FSA not contacted directly by the EPA contractor.
The questionnaire was distributed in order to locate for further
study those asbestos-containing sealant manufacturing plants that
discharge process waste waters. It also provided an opportunity for
companies that were not contacted directly to participate in the
study, if they wished. A copy of this preliminary questionnaire is
presented on the following pages. All manufacturers of asbestos-
containing sealing devices that completed and returned the ques-
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tionnaire indicated that no process waste waters are generated in
their operations.
Of the 28 questionnaires distributed, eight were returned. This
return of close to 30 percent is believed to be reasonably success-
ful in light of the fact that many members of the FSA manufacture
non-asbestos sealing devices and, hence, would have little incentive
to return the questionnaire.
GENERAL DESCRIPTION OF THE INDUSTRY
Although known as a curiosity since biblical times, asbestos was not
used in manufacturing until the latter half of the 19th century. By
the early years of the 20th century, much of the basic technology
had been developed, and the industry has grown in this country since
about that time. Canada is the world's largest producer of asbes-
tos, with the USSR and a few African countries as major suppliers.
Mines in four states; Arizona, California, North Carolina, and
Vermont, provide a relatively small proportion of the world's
supply.
Asbestos is normally combined with other materials in manufactured
products, and consequently, it loses its identity. It is a natural
mineral fiber which is very strong and flexible and resistant to
breakdown under adverse conditions, especially high temperatures.
One or more of these properties are exploited in the various manu-
factured products that contain asbestos.
Asbestos is actually a group name that refers to several serpentine
minerals having different chemical compositions, but similar char-
acteristics. The most widely used variety is chrysotile. Asbestos
fibers are graded on the basis of length, with the longest grade
priced 10 to 20 times higher than the short grades.
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QUESTIONNAIRE FORM
Company Name _.
Plant Address
Name of Contact at Plant
Telephone Number at Plant
Product(s) Manufactured
Operating Schedule: Hours per Day Days per Week
Number of Employees
Are there other plants in this company that manufacture asbestos-
containing products? Yes No
1. Do any of the products manufactured or fabricated at this
plant contain asbestos? Yes No
If "no", please stop here and return questionnaire.
If "yes", please continue below.
2. Is water used in any way in the manufacturing or auxiliary
operations? Yes No
If "no", please stop here and return questionnaire.
If "yes", please complete below.
3. Is any waste water (other than sanitary) discharged from
plant? Yes No
4. Is waste water treated before leaving plant property?
Yes No
5. Is waste water (with or without treatment) discharged to:
public sewer
stream or lake
lagoon
other (please describe)
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INDIVIDUAL PLANT QUESTIONNAIRE
6. Is information available about the quantities of waste waters
discharged? Yes No
About the waste water characteristics? Yes No
If "yes", please describe type of information!"" ~
7. Has a discharge permit application been filed for this plant?
Yes No
10
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On a world-wide basis, asbestos-cement products materials and pipe
currently consume about 70 percent of the asbestos mined. In the
United States in 1971, the consumption pattern was reported to be:
Vinyl-Asbestos Floor Tile 19.2%
Asbestos-Cement Pipe 18.7
Paper and Felt, including Roofing 14.7
Friction Materials 10.7
Asbestos-Cement Building
Materials 6.7
Packing Materials 3.3
Textiles 2.9
Asbestos Insulation 2.1
Spray-on Asbestos Materials 2.0
All Other Asbestos Products 19.0
100.0%
These figures do not accurately reflect the production levels of
these products because the asbestos content varies from about 10 to
almost 100 percent among the different manufactured products.
The asbestos manufacturing industry is classified in two SIC groups:
3292, Asbestos Products; and 3293, Gaskets, Packing and Sealing
Devices. The products covered in the earlier Phase I study of this
industry were:
Asbestos-Cement Products,
Asbestos Paper and Felt,
Asbestos Millboard,
Asbestos Roofing Products,
Asbestos Floor Tile, and
Asbestos Block Insulation.
This Phase II document includes the remaining products in these SIC
groups. They may be grouped as follows:
Textile Products - yarn, cord, rope, thread, tape,
wicks, and various fabrics.
Friction Materials - brake linings, clutch facings,
and related items.
Gaskets, seals, washers, and packings that contain asbestos,
LOCATION OF MANUFACTURERS
The locations of the 51 plants that were contacted in connection
with this study are listed in Table 1. This listing includes all of
the known manufacturers of asbestos textiles, most of the plants
engaged primarily in manufacturing friction materials, and what is
believed to be a large, representative sampling of producers of
asbestos-containing gaskets, packings, and sealing devices.
11
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TABLE 1
State
Alabama
California
Connecticut
Georgia
Illinois
Indiana
Kentucky
Massachusetts
Michigan
LOCATIONS OF ASBESTOS
City
Prattville
Fullerton
Stratford
Hogansville
Glenwood
Waukegan
Crawfordsville
Logansport
New Castle
Warsav
Danville
Lawrence
North Brookfield
Hartford
Saginaw
St . Joseph
Trenton
MANUFACTURING PLANTS - PHASE II
Company
Molded Industrial Friction Corp.
Raybestos-Manhattan
Raybestos-Manhattan
Uniroyal, Inc.
Jas . Walker Packing Company , Inc .
Johns-Man vi lie
Raybestos-Manhattan
National Friction Products Corp.
World Bestos Company
Gatke Corporation
Royal Industries Brake Products
Auto Friction Corporation
Gatke Corporation
Auto Specialties Manufacturing Co.
General Motors Corporation
Auto Specialties Manufacturing Co.
Chrysler Corporation
Products
FM
FM
*FM, S
*T
S
*S
FM
FM
FM
FM
FM
FM
FM, T, S
FM
*FM
FM
*FM
New Hampshire
Meredith
Amatex Corporation
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TABLE 1 (cont)
LOCATIONS OF ASBESTOS MANUFACTURING PLANTS - PHASE II
State
New Jersey
New York
North Carolina
Ohio
Pennsylvania
City
Cranford
Man ville
Newark
New Brunswick
North Brunswick
Patterson
Trenton
Trenton
Green Island
Palmyra
Charlotte
Laurinberg
Marshville
Boydsville
Chagrin Falls
Dayton
Dayton
Paulding
Ambler
Manheim
Norristown
North Wales
North Wales
Philadelphia
Ridgway
Company
Chempro , Inc .
Johns -Manvi lie
Reddaway
Metallo Gasket Company
Johns -Manvi lie
Brassbestos Manufacturing Corp.
Mercer Rubber Company
Thiokol Chemical Corporation
Bendix Corporation
Garlock , Inc .
H. K. Porter, Inc.
Johns-Man ville
Raybestos-Manhattan
Wheeling Brake Block Mfrg. Company
Hollow Center Packing Company , Inc .
General Motors
General Motors
Maremont Corporation
Nicolet
Raybestos-Manhattan
Amatex Corporation
Atlas Textile Company
Greene, Tweed & Company
Asten-Hill Manufacturing Company
Carlisle Corporation
Products
S
,y. m
*T
FM
S
S
FM
S
FM
*FM
T, S
T
FM
T
FM
S
*FM
*FM
FM
*T, S
FM, T, S
T
T
S
T
FM
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TABLE 1 (cont)
LOCATIONS OF ASBESTOS MANUFACTURING PLANTS - PHASE II
State
South Carolina
Tennessee
Texas
Virginia
City
Bennetsville
North Charleston
Cleveland
New Port
Houston
Houston
Houston
Winchester
Company
H. K. Porter, Inc.
Raybestos-Manhattan
Bendix Corporation
Detroit Gasket & Manufacturing Co.
Lamons Metal Gasket Company
Standee Industries
Standee Industries
Abex Corporation
Products
T
T
FM
S
S
FM
S
FM
KEY: FM - Friction Materials
S - Sealants (Gaskets, Packings, Etc.)
T - Textiles
*Waste waters from manufacture of products not covered by this study are more
significant at these plants.
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At only ten of the listed plants are process-associated waste waters
generated, and at five of these the waste waters emanate only from
wet air pollution control equipment. In most cases, the manufacture
of the products in this study is a "dry" process and does not result
in the generation of process waste waters.
MANUFACTURING PROCESSES
The basic manufacturing processes for the products in the three
groups covered are outlined below with sources of waste waters
indicated. As noted previously, water is not normally used directly
in the manufacturing operations, and the waste waters from this
segment of the asbestos industry are generated in a few special
operations not common to the industry generally.
TEXTILE PRODUCTS
The primary reasons for the use of asbestos fiber in textile
products are its properties of durability and resistance to heat,
fire, and acid. Asbestos is the only mineral that can be manufac-
tured into textiles using looms and other textile equipment. The
asbestos textile products are primarily used for friction materials,
industrial packing, electrical insulation, and thermal insulation.
Figure 1 illustrates the steps in the manufacture of the various
asbestos textile products. The textile plants receive the asbestos
fiber by railcar in 100-pound bags. The bags are opened, and the
fibers passed over vibrating screens or trommel screens for clean-
ing. The fibers are lifted from the screens by air suction and
graded. After preparation, the fiber is mixed and blended. Chry-
solite is the predominant fiber used in textiles. Crocidolite and
amosite asbestos fibers may also be added to the chrysolite. Small
percentages of cotton, rayon, and other natural or synthetic fibers
serve as carriers or supports for the shorter asbestos fibers, and
they improve the spinnability of the fiber mixture. Typically, the
organic fiber content is between 20 and 25 percent. The blending
and mixing operations are primarily done during carding of the
fibers, but can also be performed in multi-hopper blending units.
In the carding operation, the fibers are arranged by thousands of
needle-pointed wires that cover the cylinders of the carding
machine. The fibers are combed by passing between the carding
machine main cylinder and the worker cylinders rotating in the
opposite direction. The carding machine forms a continuous mat of
material. The mat is divided into strips, or slivers, and
mechanically compressed between oscillating surfaces into untwisted
strands. The strands are wound on spools to form the roving.
Roving is the asbestos textile product from which asbestos yarn is
produced.
The roving is spun into yarn in a manner similar to that employed to
manufacture cotton and wool yarns. The strands of roving are
converted into a single yarn by the twisting and pulling operations
of a spinning machine. The yarn produced by spinning and twisting
15
-------
RAYON, COTTON
OR OTHER FIBER
CARDED
1 TWISTING 1^-
TWISTING
WISTED ROPE
1 BRAIDING 1
BRAIDED
ROPE
MIXI
L_^
1
NG —
ING |— —
NG
k
SPINNING
SINGLE 1
1
T
k
r
r>
, U
— ^NON-WOVEN FELTS
LIGHT GAUGE WWE
PLIED YARNS METALLIC YARNS
i i
1COATWG L_ DRYING .^.TREATED
I^-WASTE WATER
TWISTING l^-TWISTED CORD
BRAIDING
WEAVING
^
I T I I I I
BRAIDED BRAIDED BRAIDED TAPE WOVEN CLOTH
TUBING CORD ROPE TUBING
SOLVENT
COATING
CLOTH
t
..TREATED
FABRIC
•WASTE WATER
FIGURE 1-ASBESTOS TEXTILE MANUFACTURING OPERATIONS
(From handbook of Asbestos Textiles )
16
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basic component of several other asbestos textile products.
^
Li^
Erection to pla" tne yarn together and form a braided product.
Asbestos yarn can also be twisted or braided into various shapes to
form packing and gaskets. The braided material can be impregnated
5iS PdiffSren? compounds. Graphite is commonly used *° impregnate
braided packing material, the graphite serves to lower the
frictional and binding properties of the packing.
Asbestos cloth is woven from yarn on looms that operate in a manner
similar to those used for the manufacture of other textile products.
The warp yarn is threaded through the heddles and the reed of the
loom and the filler yarn is wound on quills and placed in a shuttle.
ThTc?o~th is woven as the filler yarn in the shuttle interweaves the
warp yarn transversely. Following weaving, the asbestos cloth is
inspected for strength, weight, and asbestos content.
Asbestos yarn or cloth may be coated for fabrication into friction
rollers, brushes, or doctor blades. The coated textile product then
passes through a drying oven where the solvent is evaporated.
Water Usage
Water is not normally used in an asbestos textile manufacturing
SaSL ?vo exceptions are the addition of moisture during weaving
or braiding and the coating operations. Waste water is generated
only in the latter process.
Operating Schedule
A typical asbestos textile plant operates two or three shifts per
day and five days per week.
FRICTION MATERIALS
Molded Products
The manufacturing steps typically used in J*^£* ^i*6*^6
linina manufacture are shown in Figure 2. The bonding agents,
me^alliS constituents , asbestos fibers, and additives are weighed
and mixed in a two- stage mixer. The mix is then hand-tamped into a
metal mold. The mold is placed in a preforming press which
partially cures the molded asbestos sheet. The asbestos sheet is
laken from the preforming press, and put in a steam PFehJa^n?J^d
to soften the resin in the molded sheet. The molded sheet is formed
to the proper arc by a steam heated arc former, which resets the
resin. The arc-formed sheets are then cut to the proper size. The
lining is then baked in compression molds to retain the arc shape
17
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and convert the resin to a thermoset or permanent condition. The
lining is then finished and, after inspection, is packaged. The
finishing steps include sanding and grinding of both sides to
correct the thickness, edge grinding, and drilling of holes for
rivets. Following drilling, the lining is vacuum-cleaned,
inspected, branded, and packaged.
Figure 3 shows the major steps in the manufacture of wet-mixed
molded brake linings. The name "wet mix" process is a misnomer and
refers to the use of a solvent. The ingredients of the molded
lining are actually relatively dry. After weighing, they are mixed
in a sigma blade mixer. The mixed ingredients are then sent to
grinding screens where the particle size of the mixture is cor-
rected. The mixture is conveyed to a hopper and is forced from the
hopper into the nip of two form rollers which compress the mixture
into a continuous strip of friction material. The strip is cut into
the proper lengths and then arc-formed on a round press bar. The
cutting and arc forming operations are done by separate units. The
linings are then placed in racks and either air-dried or oven-dried
to remove the solvent. An alternative process is to place the arc-
formed linings in metal molds for baking in an oven. From the
ovens, the linings are finished, inspected, and packaged.
Molded clutch facings are produced in a manner similar to the wet-
mixed process. The rubber friction compound, solvent, and asbestos
fibers are introduced into a mixer churn. After the churn mixes the
ingredients, the mixture is conveyed to a sheeter mill which forms a
sheet or slab of the materials. The sheet is then diced into small
pieces by a rotary cutter. The pieces are placed in an extrusion
machine which forms sheets of the diced material. The sheets are
cut into the proper size and then punch-pressed into donut-shaped
sheets. The scraps from the punch press are returned to the
extrusion machine. The punched sheets are placed on racks and sent
to a drying oven and then a baking oven for final curing and solvent
evaporation. The oven-dried sheets are finally sent to the
finishing operations. Figure H illustrates the steps in the
manufacture of molded clutch facings.
H°.Y££ Products
Woven clutch facings and brake linings are manufactured of high-
strength asbestos fabric that is frequently reinforced with wire.
The fabric is predried in an oven or by an autoclave to prepare it
to be impregnated with resin. The fabric can be impregnated with
resin by several techniques: 1) immersion in a bath of resin, 2)
introducing the binder in an autoclave under pressure, 3)
introducing dry impregnating material into carded fiber before
producing yarn, and U) imparting binder into the fabric from the
surface of a roll. After the solvents are evaporated from the
fabric, it is made into brake linings or clutch facings. Brake
linings are made by calendering or hot pressing the fabric in molds.
The linings are then cut, rough ground, placed in molds, and placed
in a baking oven for final curing. Following curing, the lining is
finished, inspected, and packaged. The composition by weight of
18
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RAW MATERIALS
STORAGE
PROPORTIONING
MIXING
PREFORMING
PRESS
COOLING WATER STEAM
•fck
| PREHEAT | >COOL,NG WATER
COOLING WATER
STEAM
'CONDENSATE
ARC FORMER |
^•COOLING WATER
^•CONDENSATE
CUTTING ^•^•DUST
r
COMPRESSION MOLD
BAKING OVEN
INSPECTION
PACKAGING
STORAGE
CONSUMER
FIGURE 2-DRY-MIXED BRAKE LINING MANUFACTURING OPERATIONS
19
-------
RAW MATERIALS
STORAGE
PROPORTIONING
MIXING
GRINDING
SCREENS
TWO-ROLL
FORMING
CUTTING
ARC FORMING
AIR DRYING
DRYING OVEN
FINISHING
SOLVENT
SOLVENT
A
DUST
INSPECTION
PACKAGING
STORAGE
CONSUMER
FIGURE 3-WET-MIXED MOLDED BRAKE LINING MANUFACTURING OPERATIONS
20
-------
COOLING WATER
RAW MATERIALS
STORAGE
PROPORTIONING
STEAM
TWO-ROLL FORMING
(SHEETER MILL)
COOLING WATER
CONDENSATE
[ROTARY CUTTER J
| EXTRUSION MACHINE] \
1
fcUTTING | '
1
(RECYCLED SOLIDS)
IPUNCH PRESS
.J
SOLVENT
{DRYING OVEN j
SOLVENT
BAKING OVEN
FINISHING
DUST
INSPECTION
PACKAGING
STORAGE
4-
CONSUMER
FIGURE 4- MOLDED CLUTCH FACINGS MANUFACTURING OPERATIONS
21
-------
I TREATED FABRIC |
SLITTING
PREFORM
WINDING
COOLING WATER STEAM
PRESS
| BAKING OVEN |
COOLING WATER
CONDENSATE
FINISHING
INSPECTION
PACKAGING
STORAGE
I
DUST
CONSUMER
FIGURE 5-WOVEN CLUTCH FACINGS MANUFACTURING OPERATIONS
22
-------
woven brake linings ranges from 40 to 60 percent asbestos, 10 to 20
percent cotton, 20 to 40 percent wire, and 5 to 20 percent binder.
Figure 5 illustrates the manufacture of woven clutch facings. The
treated fabric is cut into tape-width strips by a slitting machine.
The strips are wound around a mandrel to form a roll of the fabric.
The roll is pressed in a steam-heated press and then baked in an
oven to cure the resin in the clutch facing. Following curing, the
clutch facing is finished, inspected, and packaged.
Water Usage
Water does not mix with the ingredients of friction materials and is
not used in the manufacturing processes. Waste waters are generated
in a few friction materials plants in solvent recovery operations
and in wet dust collection equipment used to control the quality of
the air from the finishing areas. Most plants in this industry use
dry dust collection equipment.
Operating Schedule
Friction materials plants typically operate two or three shifts a
day on a five- or six-day per week schedule.
GASKETS, PACKING, AND SEALING DEVICES
The gaskets, packings, and sealing devices group includes a wide
variety of products, many of which contain metallic components. The
asbestos content of these products varies widely from one type to
another. The typical plant making these products is a fabricator
rather than a manufacturer, purchasing materials that are ready for
cutting and assembly. There are many specialized hand operations in
some plants in this category. Gaskets and packings may be made from
asbestos paper, felt, and millboard; yarn, cloth, wick, and rope;
and sheet gasket material. The waste waters associated with
asbestos paper, felt, and millboard were covered in the Phase I
document.
The variety of materials and forms comprising this group of products
is so wide that it precludes general descriptions of typical
manufacturing processes.
Water Usage
In this study, no plant was found that used water in the manufacture
of gaskets, packing, and/or sealing devices. The manufacture of
sheet gasket material may involve cooling and solvent recovery
operations that produce waste waters. Among the plants contacted in
this study, only one was found that generated waste water from a
sheet gasket production facility, and this was from the solvent
recovery operations.
In summary, the fabrication of asbestos-containing gaskets, pack-
ings, and sealing devices does not normally result in process waste
23
-------
waters, although the manufacture of some of the raw materials may
result in process-associated wastes.
Operating Schedule
Sealant manufacturing plants normally operate one or two shifts for
five days a week.
CURRENT STATUS OF THE INDUSTRY
There has long been concern about the industrial hygiene aspects of
the dust and fiber emitted to the air in the asbestos manufacturing
industry. Asbestos was among the first materials to be declared a
hazardous air pollutant under the Clean Air Act amendment of 1970.
Some of the waste waters generated in this portion of the asbestos
industry result in part from measures to eliminate or reduce the
hazards. Asbestos textiles are coated to make them safer during
fabrication and when used by the consumer.
The most significant effect of the recently increased concern about
asbestos is the trend toward substitution of other materials,
especially among users of textile products. New uses and markets
for asbestos will be more difficult to develop in the future unless
means are found to reduce the potential hazards. Despite the
declines in some areas, however, the unique characteristics of
asbestos plus new developments within the industry make the outlook
for future growth favorable in the textile, friction materials, and
sealant manufacturing segments of the industry.
24
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SECTION IV
INDUSTRY CATEGORIZATION
INTRODUCTION AND CONCLUSIONS
In developing effluent limitations guidelines and standards of
performance for new sources for a given industry, a judgment was
made by EPA as to whether different effluent limitations and
standards were appropriate for different segments (subcategories)
within the industry. The factors considered in determining whether
such categories were justified for this part of the asbestos
manufacturing industry were:
1. Product,
2. Raw Materials,
3. Manufacturing Process,
4. Characteristics and Treatability of Waste Waters,
5. Air Pollution Control Equipment,
6. Plant Size,
7. Plant Age, and
8. Geographic Location.
Based on review of the literature, plant visits and interviews, and
consultation with industry representatives, the above factors were
evaluated and it was concluded that this part of the asbestos
manufacturing industry (Phase II) should be divided into four sub-
categories:
1. Coating, or finishing, of asbestos textiles,
2. Solvent recovery operations,
3. Vapor absorption equipment (fume scrubber), and
4. Wet particulate (dust) collectors.
In addition to the above, it should be noted that there is a poten-
tial source of waste water in this part of the asbestos industry;
namely, the manufacture of yarn by the dispersion process. At the
time of this study, two plants in the country have pilot-plant or
experimental manufacturing operations using this process. The level
of production is extremely limited today, but it could increase in
the future. While these operations are too limited to be considered
in this study, it was determined that, even with in-plant controls,
the associated waste waters can be expected to contain both organic
and inorganic pollutants. If this process becomes operational,
separate effluent limitations guidelines should be developed.
FACTORS CONSIDERED
All of the factors listed above are briefly discussed below, even
though most of them did not serve as bases for categorization.
25
-------
Product
The products included in this part of the asbestos industry cover a
wide range of manufactured items and materials, many of which are
related only in that they contain asbestos fibers. Textiles are
manufactured into many special-use articles and are also converted
into friction materials and sealing devices. Some plants consume
all of their textile production in manufacturing brake linings,
clutch facings, and other friction products. Non-fabric friction
materials and gaskets are also produced in large quantities, in some
cases, in the same plants manufacturing textile-based counterparts.
In sum, categorization by product would tend to confuse, rather than
clarify, understanding and analysis of the industry.
Raw Materials
Many raw materials are used in this industry and most have a marked
influence on the nature and treatability of the wastes. However,
because of the small number of waste water sources, categorization
in terms of raw materials is not useful. In other words, where the
raw materials result in distinctive differences in the wastes, the
individual plants are not similar. Categorization based on raw
materials would result in several categories with only one plant in
each.
Manufacturing Process
Within this industry, there are two fully developed manufacturing
processes that may result in the generation of waste waters. One is
the coating of asbestos textiles to be made into industrial belting,
friction materials, special articles, etc. Waste waters may result
from the cleaning of the preparation and application equipment,
dumps, and from the housekeeping operations. The other
manufacturing operation that may result in waste waters is the
recovery of solvents from drying oven exhaust air using activated
carbon. The solvents are removed from the exhaust air by absorption
on the carbon, recovered from the carbon by steam stripping, and
then decanted or distilled from the condensate. The resulting waste
water may contain residual solvent or other materials evaporated
from the product during drying. Solvent recovery is not unique with
the asbestos textile industry, but is used to a limited degree in
the manufacture of friction materials and sheet gasketing. The
presence or absence of this operation provides a basis for
categorizing plants in the industry.
Characteristics and Treatability of Waste Waters
The term "characteristics" is used here to include both the inten-
sive and extensive properties of the waste waters, i.e., the
chemical and physical parameters plus the volumes of wastes and the
rates of discharge. Most of the significant waste water pollutants
from this industry fall broadly into two categories; dissolved
organic materials (COD) from the textile coating and the solvent
recovery and vapor absorption operations; and suspended solids from
the wet particulate collectors. While the organic materials have
some similarities, they vary in their amenability to various
26
-------
treatment technologies. The rates of discharge are so dissimilar
that different control measures and effluent limitations are
indicated. In one case (textile coating), a very small quantity of
concentrated waste is discharged irregularly. In the second case
(solvent recovery), a steady flow of moderate volume results. In
the third (vapor absorption), a larger volume of dilute waste is
discharged, but only intermittently. The different characteristics
make different control and treatment technologies appropriate. The
quality of the discharge from the dust collectors varies with the
type of equipment and the degree of water recirculation, as well as
the particulate load in the air stream.
While categorization based on the waste water characteristics is
useful, this factor cannot be fully utilized. As noted in the dis-
cussion on raw materials above, there is only a small number of
sources in this industry and each produces an effluent that is truly
unique. There is little benefit in classifying plants if the result
is only one plant in each category.
Ai£ Pollution Control Eguipment
In most of the plants in this industry, particulate emissions are
controlled by baghouses or other dry devices. In a few wet plants,
wet dust collectors are used and a waste water results.
Where small quantities of solvents are used, they may be wasted
rather than be recovered. Among the techniques used for controlling
the emissions of vaporized materials is absorption in water, which
may result in a waste water effluent.
The type of air pollution control equipment used in this industry
provides a useful basis for categorization.
Plant Size
The plants in this industry that generate waste waters range from
the small (50 to 70 employees) to the medium in size (1000
employees) . As pointed out previously, the characteristics of the
waste waters are independent of the level of production, and some of
the small plants generate more waste than larger ones. Plant size
has no significant effect on the quality or treatability of the
waste waters.
Plant Age
The ages of the plants in this part of the asbestos manufacturing
industry range from a few to 50 or more years. The manufacturing
equipment is normally younger than the building housing the plant.
Plant age, like plant size, could not be correlated with operational
efficiency, quality of housekeeping, or waste water characteristics.
Plant age is not an appropriate basis for categorization of the
industry.
27
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Geographic Location
As presented in Section III, almost all of the plants in this part
of the asbestos manufacturing industry are located east of the
Mississippi River. A few plants are located in California and
Texas. The basic manufacturing processes used are similar
throughout the industry, and geographic location does not influence
the processes or the waste water characteristics. Location does not
provide a basis for categorizing this industry.
28
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SECTION V
WATER USE AND WASTE CHARACTERIZATION
Other than for steam generation and noncontact cooling, water is not
widely used in the manufacturing processes in this part of the
asbestos industry. In a few individual plants, water is used in
process-related operations and waste waters are discharged from the
plant property. The water usage and waste characteristics are
described in detail in this section.
It should be noted that there are manufacturing processes that are
termed "wet" within this industry, but are actually dry in that no
waste water is generated. Examples include the "wet mixed" methods
for manufacturing molded friction products. Solvents are used to
make the mix more pliable during the rolling, extruding, or other
molding operation. Another example is the addition of moisture to
asbestos yarn during weaving to produce a tighter fabric. This is
accomplished by mist sprays or by running the yarn through water.
In the textile mills that "wet" weave, no excess water is used, and,
in fact, there are no floor drains in the weaving areas.
For each of the subcategories in this industry, the waste water
characteristics are described below. In all cases, the quantity of
water used cannot be directly related to the level of production,
and raw waste loads cannot be expressed in terms of production
units. Because only a small number of plants generate process-
related waste waters, the data base is not large. Each plant is
unique and the information presented here is based on all data that
are available about these waste waters.
TEXTILE COATING
Waste waters result from the coating of asbestos textiles at two
plants in the country at the present time. Where textile products
are coated (impregnated) in the manufacture of friction materials
and sealing devices, water is not used and no waste water is gen-
erated.
Water Usage
The volume of waste generated in the coating of asbestos textiles is
estimated to be no more than 750 liters (200 gallons) per day. The
coating of asbestos textiles is not presently a full-time operation
at either of the two plants. The waste results from dumps and
cleanup at the end of a run. The number and length of the runs
varies on a typical day, making the quantity of waste largely
independent of the quantity of textile treated, or the level of
production.
29
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Waste Characteristics
Coated asbestos textiles are used in a variety of products; e.g.,
pipe lagging, paper machine felts, ironing board covers, etc. One
of the purposes of coating is to encase the fibers, thereby reducing
the potential health hazards in fabricating and using the final
products. The coating has additional functions and its composition
is normally specified by the fabricator. Consequently, the chemical
constituents of the coating material, and subsequently those of the
waste water, vary at each of the plants. The ingredients include
resins, elastomers, pigments, solvents, and fillers. The wastes are
high in COD and suspended and dissolved solids. In addition to the
organic components, trace quantities of heavy metals, phosphates,
and fluorides may be present.
At both of the plants that coat asbestos textiles, the waste waters
are discharged to municipal sewerage systems, one with pretreatment
and the other without. Other than knowing the quantities of raw
materials used, neither plant has information on the characteristics
of its waste waters.
SOLVENT RECOVERY
Waste waters are known to be generated in solvent recovery
operations at two plants in this industry.
Water Usage
The quantity of waste water from solvent recovery operations varies,
depending upon the type and the size of the equipment. A typical
value is 38,000 liters (10,000 gallons) per day for this industry.
The discharge is normally steady and, since it is a function of the
activated carbon regeneration process, it cannot be directly related
to the level of production in the plant.
Waste Characteristics
The waste waters from solvent recovery units may contain residual
solvent and/or other organic materials that are either evaporated
from the product or generated during the recovery operations. The
suspended solids level is normally very low, and the waste water may
have an elevated temperature. Typical waste water characteristics
from one solvent recovery operation are as follows:
BOD (5-day) 1125 mg/1
COD 1930 mg/1
Suspended Solids 0 mg/1
The waste waters from this plant are discharged with the sanitary
wastes to the municipal sewerage system. The waste waters from the
other known plant that recovers solvent are combined with larger
volumes of industrial waste waters (covered in the Phase I report on
the asbestos industry) for treatment prior to discharge to a surface
water. The BOD of the combined, treated effluent from the plant is
less than 20 mg/1. There are plans at this plant to completely
recycle all process-related waste waters.
30
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VAPOR ABSORPTION
At one of the two asbestos textile coating plants, a vapor absorp-
tion unit is used to scrub solvent from the drying oven exhaust.
Water Use
The fume scrubber at the single known installation in this industry
is operated once or twice a month for a two-shift period each time.
The water usage rate is about 3.8 liters per second (60 gallons per
minute) for a total volume per period of approximately 220 cubic
meters (58,000 gallons). The scrubber comprises four chambers, and
water is recirculated within the unit.
Waste Characteristics
The vapor absorption unit is charged with 22.7 kilograms (50 pounds)
of sodium hydroxide in solution for each period of operation. The
resulting waste water, therefore, contains this caustic plus the
absorbed solvent. The waste is pretreated in a two-stage lagoon
prior to discharge to the municipal sewerage system. There are no
records available that describe the characteristics of the raw waste
water resulting from the vapor absorption unit. It should have a
somewhat elevated pH value and a significant COD content.
WET DUST COLLECTION
At this time, there are known to be four friction materials manu-
facturing plants that discharge waste waters from wet dust collec-
tion equipment. Based on the results of this study, it is estimated
that the total number of such plants in the country is no more than
eight. At all of the known plants, the waste waters are clarified
before discharge to surface waters. At one of the four, the wastes
are combined with metal-finishing wastes in a physical-chemical
treatment facility.
Water Usage
The water use rate in wet dust collectors varies from 0.06 to 1.3
liters per second per cubic meter per minute of air scrubbed (0.5 to
10 gpm per 1000 scfm). The plant air systems that are served by wet
scrubbers that discharge waste waters from the plant property range
from 280 to 1700 cubic meters per minute (10,000 to 60,000 scfm),
resulting in waste water discharges of from 190 to 570 cubic meters
(50,000 to 150,000 gallons) per day. The units that incorporate
recirculation discharge a settled slurry. In addition, the contents
of the settling tank are dumped, usually once per week. As noted
above, the wastes are discharged to a settling lagoon in all known
cases.
W§ste Characteristics
The waste waters from the wet dust collectors are slurries of the
dust emenating from the grinding and drilling operations used in
31
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finishing friction products. The principal parameter for charac-
terizing the wastes is suspended solids. Because friction materials
are specifically designed to shed water, it is unlikely that the
dust is solubilized to any measurable degree. The COD test provides
a convenient means of detecting and monitoring this phenomenon if it
is suspected.
The quantity of friction material that is lost in the finishing
operations may be as much as 30 percent. It is significant that,
even with the relatively high price of asbestos fiber, this material
is not recovered for reuse. Once the resin has set up, it is not
regarded as economical to break it down to salvage the fiber.
DISPERSION PROCESS
As noted in Section IV, there are two known experimental pilot-plant
operations in the country where asbestos yarn is being produced in
very limited quantities by the dispersion process. While these
operations are too limited for inclusion as subcategories in this
industry, it is deemed appropriate to include what information is
available about the waste waters for use when and if this method
becomes operational and is more widely used.
Water Usage
The water use rate is in the order of 20 to 60 cubic meters (5000 to
15,000 gallons) per day in these pilot-plant operations. Because
these facilities are very small, water usage based on production
cannot be realistically extrapolated to plant-scale operations. The
water passes through save-alls in the process and there is at least
a potential for recycle of water. Because of the waste
characteristics, it is not feasible at this time to completely reuse
all water in this process.
Waste Characteristics
The waste waters from the two plants that are developing the dis-
persion process differ significantly, in part because the processes
are not exactly the same. It is possible that the wastes will
change significantly as the processes are refined and developed.
Some of the parameters that should be measured are total and sus-
pended solids; COD and BOD; hexane extractables; MBAS; zinc and
other metals; and the plant nutrients, nitrogen and phosphorus.
PLANT DESCRIPTIONS
Forty-five manufacturing plants representing 30 different companies
or corporations were contacted directly in this study. Information
was collected from six additional plants through a questionnaire.
This coverage is believed to include better than 80 percent of all
the plants that are properly within the two SIC classes, and it
represents an accurate picture of this segment of the asbestos
manufacturing industry. A total of ten plants were found that
32
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discharge process-related waste waters. These plants are described
individually in Table 2.
In reviewing Table 2, it should be noted that the discharges from
the two plants using the dispersion process for making asbestos yarn
are included, even though these operations are experimental and not
yet classified as subcategories of this industry. Of the remaining
eleven waste streams, seven result from air pollution control
equipment and only four from manufacturing and associated
operations.
33
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TABLE 2
GENERAL DESCRIPTION OF KNOW WASTE WATER SOURCES
ASBESTOS MANUFACTURING PLANTS - PHASE II
Plant
Product
Waste Water Source Treatment Provided
Effluent Discharged To
co
A Textiles
B Textiles
B Textiles
C Textiles
D Textiles
D Sheet Gasketing
E Friction Materials
F Friction Materials
G Friction Materials
H Friction Materials
Coating
Coating
Fume Scrubber
Dispersion Process
Dispersion Process
Solvent Recovery
Dust Scrubber
Dust Scrubber
Dust Scrubber
Dust Scrubber
None
Two-Stage Lagoon
Two-Stage Lagoon
Filtration
None/Lagoon
Lagoon
Lagoon
Sedimentation
Two-Stage Lagoon
Lagoon
Municipal Sewer
Municipal Sewer
Municipal Sewer
Municipal Sewer
Municipal Sewer/
Surface Water
Surface Water
No Discharge
Surface Water
Surface Water
Surface Water
-------
TABLE 2 (cont)
GENERAL DESCRIPTION OF KNOWN WASTE WATER SOURCES
ASBESTOS MANUFACTURING PLANTS - PHASE II
Plant
Product
Waste Water Source
Treatment Provided
Effluent Discharged To
CO
cn
I Friction Materials
I Friction Materials
J Friction Materials
Solvent Recovery
Dust Scrubber
Dust Scrubber
None
Lagoon
Chemical Precipitation
with Other Wastes
Municipal Sewer
No Discharge
Surface Water
-------
SECTION VI
SELECTION OF POLLUTANT PARAMETERS
The chemical, physical, and biological parameters that define the
pollutant constituents in process-related waste waters from this
part of the asbestos manufacturing industry are the following:
COD (or TOC)
Suspended Solids
PH
Temperature
BOD
Dissolved Solids
Heavy Metals
Phenols
Nitrogen
Phosphorus
The first two listed parameters are the most significant and useful
in characterizing the wastes from this industry. The others are
included because they may also be significant in one or more
subcategories or because they supplement and support the first two
listed parameters. The rationale for selection of the listed
parameters is given below.
Pollutants in non-process waste waters; such as noncontact cooling
water, boiler blowdown, steam condensate, and wastes from water
sanitary facilities, are not included in this document.
MAJOR POLLUTANTS
The reasons for including the above listed parameters are briefly
presented below. The reader is referred to other sources (Section
XIII) for detailed descriptions of the parameters and procedures for
measuring them.
Demand
Chemical Oxygen Demand (COD) provides a measure of the equivalent
oxygen required to chemically oxidize the organic and inorganic
material present in a waste water. In this part of the asbestos
industry, the COD serves as the primary parameter for measuring the
organic materials in the raw and treated wastes, including solvents,
resins, elastomers, and fillers. COD values in excess of 1000 mg/1
occur in the wastes from the textile coating and solvent recovery
subcategories. In order to be most meaningful when used to monitor
solubilization in wet dust collection subcategory, the sample should
be filtered prior to COD analysis.
If desired, the Total Organic Carbon (TOC) parameter may be sub-
stituted for COD, with the appropriate adjustments in values. This
37
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instrumental technique yields results in terms of carbon
concentrations, rather than oxygen.
Suspended Solids
The suspended solids parameter is especially useful with the waste
water from the wet dust collectors and textile coating subcategor-
ies. The suspended solids level in the raw wastes may range up to
the very high values, exceeding 10,000 mg/1, depending upon the
operational mode of the equipment, i.e., the level of dilution used.
The suspended solids in the waste waters from the solvent recovery
and vapor absorption subcategories should be negligible if the
equipment is properly operated.
Suspended solids include both organic and inorganic materials. The
inorganic components include sand, silt, and clay. The organic
fraction includes such materials as grease, oil, tar, animal and
vegetable fats, various fibers, sawdust, hair, and various materials
from sewers. These solids may settle out rapidly and bottom
deposits are often a mixture of both organic and inorganic solids.
They adversely affect fisheries by covering the bottom of the stream
or lake with a blanket of material that destroys the fish-food
bottom fauna or the spawning ground of fish. Deposits containing
organic materials may deplete bottom oxygen supplies and produce
hydrogen sulfide, carbon dioxide, methane, and other noxious gases.
In raw water sources for domestic use, state and regional agencies
generally specify that suspended solids in streams shall not be
present in sufficient concentration to be objectionable or to
interfere with normal treatment processes. Suspended solids in
water may interfere with many industrial processes, and cause
foaming in boilers, or encrustations on equipment exposed to water,
especially as the temperature rises. Suspended solids are
undesirable in water for textile industries; paper and pulp;
beverages; dairy products; laundries; dyeing; photography; cooling
systems, and power plants. Suspended particles also serve as a
transport mechanism for pesticides and other substances which are
readily sorbed into or onto clay particles.
Solids may be suspended in water for a time, and then settle to the
bed of the stream or lake. These settleable solids discharged with
man's wastes may be inert, slowly biodegradable materials, or
rapidly decomposable substances. While in suspension, they increase
the turbidity of the water, reduce light penetration and impair the
photosynthetic activity of aquatic plants.
Solids in suspension are aesthetically displeasing. When they
settle to form sludge deposits on the stream or lake bed, they are
often much more damaging to the life in water, and they retain the
capacity to displease the senses. Solids, when transformed to
sludge deposits, may do a variety of damaging things, including
blanketing the stream or lake bed and thereby destroying the living
spaces for those benthic organisms that would otherwise occupy the
habitat. When of an organic and therefore decomposable nature,
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solids use a portion or all of the dissolved oxygen available in the
area. Organic materials also serve as a seemingly inexhaustible
food source for sludgeworms and associated organisms.
Turbidity is principally a measure of the light absorbing properties
of suspended solids. It is frequently used as a substitute method
of quickly estimating the total suspended solids when the
concentration is relatively low.
OTHER POLLUTANTS
ESx Acidity and Alkalinity
Normally, waste waters in the four subcategories fall in the neutral
pH range, i.e., 6 to 9. In the vapor absorption subcategory, how-
ever, alkali is used in the scrub water and the pH may be above 9.
Because this parameter is readily measurable and because it provides
an indication of changes or upsets, it should be included in the
list of regularly monitored parameters.
Acidity and alkalinity are reciprocal terms. Acidity is produced by
substances that yield hydrogen ions upon hydrolysis and alkalinity
is produced by substances that yield hydroxyl ions. The terms
"total acidity" and "total alkalinity" are often used to express the
buffering capacity of a solution. Acidity in natural waters is
caused by carbon dioxide, mineral acids, weakly dissociated acids,
and the salts of strong acids and weak bases. Alkalinity is caused
by strong bases and the salts of strong alkalies and weak acids.
The term pH is a logarithmic expression of the concentration of
hydrogen ions. At a pH of 7, the hydrogen and hydroxyl ion
concentrations are essentially equal and the water is neutral.
Lower pH values indicate acidity while higher values indicate
alkalinity. The relationship between pH and acidity or alkalinity
is not necessarily linear or direct.
Waters with a pH below 6.0 are corrosive to water WOJ.KS structures,
distribution lines, and household plumbing fixtures and can thus add
such constituents to drinking water as iron, copper, zinc, cadmium
and lead. The hydrogen ion concentration can affect the "taste" of
the water. At a low pH water tastes "sour". The bactericidal
effect of chlorine is weakened as the pH increases, and it is
advantageous to keep the pH close to 7. This is very significant
for providing safe drinking water.
Extremes of pH or rapid pH changes can exert stress conditions or
kill aquatic life outright. Dead fish, associated algal blooms, and
foul stenches are aesthetic liabilities of any waterway. Even
moderate changes from "acceptable" criteria limits of pH are
deleterious to some species. The relative toxicity to aquatic life
of many materials is increased by changes in the water pH.
Metalocyanide complexes can increase a thousand-fold in toxicity
with a drop of 1.5 pH units. The availability of many nutrient
39
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substances varies with the alkalinity and acidity. Ammonia is more
lethal with a higher pH.
The lacrimal fluid of the human eye has a pH of approximately 7.0
and a deviation of 0.1 pH unit from the norm may result in eye
irritation for the swimmer. Appreciable irritation will cause
severe pain.
Temperature
The waste waters associated with the solvent recovery category may
be hot, with temperatures as high as 80C, if distillation is used to
separate the solvent from the condensed steam. Because elevated
water temperatures influence the efficiency of treatment
technologies and are harmful to aquatic life, the temperature of the
raw wastes should be monitored.
Temperature is one of the most important and influential water
quality characteristics. Temperature determines those species that
may be present; it activates the hatching of young, regulates their
activity, and stimulates or suppresses their growth and development;
it attracts, and may kill when the water becomes too hot or becomes
chilled too suddenly. Colder water generally suppresses
development. Warmer water generally accelerates activity and may be
a primary cause of aquatic plant nuisances when other environmental
factors are suitable.
Temperature is a prime regulator of natural processes within the
water environment. It governs physiological functions in organisms
and, acting directly or indirectly in combination with other water
quality constituents, it affects aquatic life with each change.
These effects include chemical reaction rates, enzymatic functions,
molecular movements, and molecular exchanges between membranes
within and between the physiological systems and the organs of an
animal.
Chemical reaction rates vary with temperature and generally increase
as the temperature is increased. The solubility of gases in water
varies with temperature. Dissolved oxygen is decreased by the decay
or decomposition of dissolved organic substances and the decay rate
increases as the temperature of the water increases reaching a
maximum at about 30°C (86°F). The temperature of stream water, even
during summer, is below the optimum for pollution-associated
bacteria. Increasing the water temperature increases the bacterial
multiplication rate when the environment is favorable and the food
supply is abundant.
Reproduction cycles may be changed significantly by increased
temperature because this function takes place under restricted
temperature ranges. Spawning may not occur at all because
temperatures are too high. Thus, a fish population may exist in a
heated area only by continued immigration. Disregarding the
decreased reproductive potential, water temperatures need not reach
lethal levels to decimate a species. Temperatures that favor
40
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competitors, predators, parasites, and disease can destroy a species
at levels far below those that are lethal.
Fish food organisms are altered severely when temperatures approach
or exceed 90°F. Predominant algal species change, primary
production is decreased, and bottom associated organisms may be
depleted or altered drastically in numbers and distribution.
Increased water temperatures may cause aquatic plant nuisances when
other environmental factors are favorable.
Synergistic actions of pollutants are more severe at higher water
temperatures. Given amounts of domestic sewage, refinery wastes,
oils, tars, insecticides, detergents, and fertilizers more rapidly
deplete oxygen in water at higher temperatures, and the respective
toxicities are likewise increased.
When water temperatures increase, the predominant algal species may
change from diatoms to green algae, and finally at high temperatures
to blue-green algae, because of species temperature preferentials.
Blue-green algae can cause serious odor problems. The number and
distribution of benthic organisms decreases as water temperatures
increase above 90°F, which is close to the tolerance limit for the
population. This could seriously affect certain fish that depend on
benthic organisms as a food source.
r
The cost of fish being attracted to heated water in winter months
may be considerable, due to fish mortalities that may result when
the fish return to the cooler water.
Rising temperatures stimulate the decomposition of sludge, formation
of sludge gas, multiplication of saprophytic bacteria and fungi
(particularly in the presence of organic wastes), and the
consumption of oxygen by putrefactive processes, thus affecting the
esthetic value of a water course.
In general, marine water temperatures do not change as rapidly or
range as widely as those of freshwaters. Marine and estuarine
fishes, therefore, are less tolerant of temperature variation.
Although this limited tolerance is greater in estuarine than in open
water marine species, temperature changes are more important to
those fishes in estuaries and bays than to those in open marine
areas, because of the nursery and replenishment functions of the
estuary that can be adversely affected by extreme temperature
changes.
Biochemical Oxygen Demand jBQD)
The Biochemical Oxygen Demand (BOD) technique provides a means of
estimating the usefulness of biological treatment processes for
controlling the discharge of organic pollutants. It also provides
an indication of the effect of the waste on the oxygen budget in a
receiving water. For this part of the asbestos industry, the BOD
parameter extends the COD results and is useful when biotreatment is
under consideration. Some of the organic materials present in the
41
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waste waters are not readily biodegradable, however, and will not
respond in the test.
Biochemical oxygen demand (BOD) is a measure of the oxygen consuming
capabilities of organic matter. The BOD does not in itself cause
direct harm to a water system, but it does exert an indirect effect
by depressing the oxygen content of the water. Sewage and other
organic effluents during their processes of decomposition exert a
BOD, which can have a catastrophic effect on the ecosystem by
depleting the oxygen supply. Conditions are reached frequently
where all of the oxygen is used and the continuing decay process
causes the production of noxious gases such as hydrogen sulfide and
methane. Water with a high BOD indicates the presence of
decomposing organic matter and subsequent high bacterial counts that
degrade its quality and potential uses.
Dissolved oxygen (DO) is a water quality constituent that, in
appropriate concentrations, is essential not only to keep organisms
living but also to sustain species reproduction, vigor, and the
development of populations. Organisms undergo stress at reduced DO
concentrations that make them less competitive and able to sustain
their species within the aquatic environment. For example, reduced
DO concentrations have been shown to interfere with fish population
through delayed hatching of eggs, reduced size and vigor of embryos,
production of deformities in young, interference with food
digestion, acceleration of blood clotting, decreased tolerance to
certain toxicants, reduced food efficiency and growth rate, and
reduced maximum sustained swimming speed. Fish food organisms are
likewise affected adversely in conditions with suppressed DO. Since
all aerobic aquatic organisms need a certain amount of oxygen, the
consequences of total lack of dissolved oxygen due to a high BOD can
kill all inhabitants of the affected area.
If a high BOD is present, the quality of the water is usually
visually degraded by the presence of decomposing materials and algae
blooms due to the uptake of degraded materials that form the
foodstuffs of the algal populations.
Dissolved Solids
The dissolved solids content, when coupled with the suspended solids
value, provides a measure of the total quantity of foreign material
present in a waste water. With the wastes in this industry, the
dissolved solids parameter is useful in corroborating the accuracy
of the COD results. Since the analytical procedure involves
evaporation, some organic materials, e.g., certain solvents, may not
be detected.
In natural waters the dissolved solids consist mainly of carbonates,
chlorides, sulfates, phosphates, and possibly nitrates of calcium,
magnesium, sodium, and potassium, with traces of iron, manganese and
other substances.
42
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Many communities in the United States and in other countries use
water supplies containing 2000 to 4000 mg/1 of dissolved salts, when
no better water is available. Such waters are not palatable, may
not quench thirst, and may have a laxative action on new users.
Waters containing more than 4000 mg/1 of total salts are generally
considered unfit for human use, although in hot climates such higher
salt concentrations can be tolerated whereas they could not be in
temperate climates. Waters containing 5000 mg/1 or more are
reported to be bitter and act as bladder and intestinal irritants.
It is generally agreed that the salt concentration of good,
palatable water should not exceed 500 mg/1.
Limiting concentrations of dissolved solids for fresh-water fish may
range from 5,000 to 10,000 mg/1, according to species and prior
acclimatization. Some fish are adapted to living in more saline
waters, and a few species of fresh-water forms have been found in
natural waters with a salt concentration of 15,000 to 20,000 mg/1.
Fish can slowly become acclimatized to higher salinities, but fish
in waters of low salinity cannot survive sudden exposure to high
salinities, such as those resulting from discharges of oil-well
brines. Dissolved solids may influence the toxicity of heavy metals
and organic compounds to fish and other aquatic life, primarily
because of the antagonistic effect of hardness on metals.
Waters with total dissolved solids over 500 mg/1 have decreasing
utility as irrigation water. At 5,000 mg/1 water has little or no
value for irrigation.
Dissolved solids in industrial waters can cause foaming in boilers
and cause interference with cleaness, color, or taste of many
finished products. High contents of dissolved solids also tend to
accelerate corrosion.
Specific conductance is a measure of the capacity of water to convey
an electric current. This property is related to the total
concentration of ionized substances in water and water temperature.
This property is frequently used as a substitute method of quickly
estimating the dissolved solids concentration.
Heavy. Metals
Some of the additives used in the textile coating subcategory con-
tain heavy metals. The raw wastes should be monitored for those
metals that are contained in the raw materials.
Phenols
The waste waters from one solvent recovery operation are known to
contain about 12 mg/1 of phenol. This material is derived from the
material used to impregnate woven friction materials and is
evaporated from the product in the drying oven. Since phenols are
especially troublesome in receiving waters, this parameter is
included for use, as appropriate.
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Phenols and phenolic wastes are derived from petroleum, coke, and
chemical industries; wood distillation; and domestic and animal
wastes. Many phenolic compounds are more toxic than pure phenol;
their toxicity varies with the combinations and general nature of
total wastes. The effect of combinations of different phenolic
compounds is cumulative.
Phenols and phenolic compounds are both acutely and chronically
toxic to fish and other aquatic animals. Also, chlorophenols
produce an unpleasant taste in fish flesh that destroys their
recreational and commercial value.
It is necessary to limit phenolic compounds in raw water used for
drinking water supplies, as conventional treatment methods used by
water supply facilities do not remove phenols. The ingestion of
concentrated solutions of phenols will result in severe pain, renal
irritation, shock and possibly death.
Phenols also reduce the utility of water for certain industrial
uses, notably food and beverage processing, where it creates
unpleasant tastes and odors in the product.
Nitrogen
The nitrogen levels in the waste waters from the subcategories
covered here are not known to be significantly high. Nitrogen-
containing compounds are used as additives in the textile coating
formulations, however, and the nitrogen level of the waste waters
should be evaluated.
Phosphorus
Like nitrogen, there are no reliable data as to phosphorus levels in
the wastes in this part of the asbestos industry. Phosphorus-
containing materials are used in small amounts in the textile
coating formulations, and the use of this parameter should be
evaluated.
During the past 30 years, a formidable case has developed for the
belief that increasing standing crops of aquatic plant growths,
which often interfere with water uses and are nuisances to man,
frequently are caused by increasing supplies of phosphorus. Such
phenomena are associated with a condition of accelerated
eutrophication or aging of waters. It is generally recognized that
phosphorus is not the sole cause of eutrophication, but there is
evidence to substantiate that it is frequently the key element in
all of the elements required by fresh water plants and is generally
present in the least amount relative to need. Therefore, an
increase in phosphorus allows use of other, already present,
nutrients for plant growths. Phosphorus is usually described, for
this reasons, as a "limiting factor."
When a plant population is stimulated in production and attains a
nuisance status, a large number of associated liabilities are
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immediately apparent. Dense populations of pond weeds make swimming
dangerous. Boating and water skiing and sometimes fishing may be
eliminated because of the mass of vegetation that serves as an
physical impediment to such activities. Plant populations have been
associated with stunted fish populations and with poor fishing.
Plant nuisances emit vile stenches, impart tastes and odors to water
supplies, reduce the efficiency of industrial and municipal water
treatment, impair aesthetic beauty, reduce or restrict resort trade,
lower waterfront property values, cause skin rashes to man during
water contact, and serve as a desired substrate and breeding ground
for flies.
Phosphorus in the elemental form is particularly toxic, and subject
to bioaccumulation in much the same way as mercury. Colloidal
elemental phosphorus will poison marine fish (causing skin tissue
breakdown and discoloration). Also, phosphorus is capable of being
concentrated and will accumulate in organs and soft tissues.
Experiments have shown that marine fish will concentrate phosphorus
from water containing as little as 1 ug/1.
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SECTION VII
CONTROL AND TREATMENT TECHNOLOGY
INTRODUCTION
When classified in terms of the major waste water pollutants, those
segments of the asbestos manufacturing industry covered in this
document fall into two groups: (1) textile coating, solvent
recovery, and vapor absorption; and (2) wet dust collection. The
waste waters from the first group contain significant levels of
organic materials in solution. The raw wastes from textile coating
may also contain suspended materials that will settle in quiescent
conditions. The wastes from wet dust collectors are entirely
suspended solids with minimal dissolved organic content. Some of
the in-plant control measures apply to both groups, but the end-of-
pipe treatment technologies are basically different.
Treatment
Within this industry, the only end-of-pipe treatment technology in
use is sedimentation, normally in lagoons. While this operation may
be adequate for waste waters from wet dust collectors, it is
inappropriate as the sole method of treatment for the first group of
subcategories. It should be pointed out that some friction
materials manufacturing plants provide treatment beyond sedimenta-
tion. These are primarily for wastes from non-asbestos manufac-
turing, e.g., metal finishing operations, and wastes from the wet
dust collectors are treated in the same facility.
The control technologies recommended here are addressed at the
principal pollutant parameters, namely COD, suspended solids, and
pH. There are insufficient data available to ascertain the need for
additional control measures for such dissolved pollutants as heavy
metals, phenols, and plant nutrients. In most of the known cases,
the costs of end-of-pipe treatment technologies more advanced than
those recommended here are so high that alternative solutions will
be used, e.g., substitution of baghouses for wet dust scrubbers in
friction materials plants. At some of the plants, such a
substitution program, on a phased schedule, has already been
initiated.
Implementation
Based on the available information, the in-plant control measures
and end-of-pipe treatment technology outlined below can be imple-
mented as necessary within the appropriate subcategories of the
industry. Factors relating to plant and equipment age, manufac-
turing process and capacity, and land availability do not generally
play significant roles in determining whether a given plant can make
the changes. Because so few plants are actually affected today, the
recommended technology has been defined with all of the known plants
in mind. Implementation of a particular control or treatment
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measure will involve approximately -the same degree of engineering
and process design skill and will have the same effects on plant
operations, product quality, and process flexibility at all
locations. Each plant is unique, however, and the possibility of
peculiar requirements should not be ignored.
IN-PLANT CONTROL MEASURES
In some friction materials plants, water is recirculated in the wet
dust collectors. This is the only in-plant control measure that is
generally used in this industry. Other in-plant measures, as
described below, have been implemented at individual plants to
eliminate the generation or discharge of process-related waste
waters.
Raw Material Storage
Raw materials are normally stored indoors and in containers. There
is no widespread water pollution problem related to improper or
inadequate raw material storage practices.
5?lSi® Water Segregation
In all cases, sanitary sewage should be discharged separately from
process-related waste waters. Public health considerations as well
as economic factors dictate that sanitary wastes not be combined
with process-related wastes for on-site treatment.
In all four subcategories, the waste waters originate at one point
in the process or the auxiliary operation. The wastes, therefore,
can be isolated for separate control. In many plants, the wastes
are diluted with cleaner waters, such as spent cooling water and
steam condensate. By mixing these streams, the entire discharge
becomes, by definition, a process-related waste subject to control.
These clean water discharges should be segregated and managed
separately.
Housekeeping Practices
The only subcategory where housekeeping practices influence the
quality of the waste water is textile coating. Since the waste
results primarily from clean-up of equipment and dumps, changes here
can result in significant improvements in the quality of the waste
waters.
Water Usage
Attention should be directed toward water conservation in all sub-
categories. In the clean-up operations in asbestos textile coating,
there is a tendency to use more water than is required. The water
used in the vapor absorption and dust collection equipment should be
reduced to the minimal level dictated by air quality requirements.
Spent cooling water, where available, can be used for these
operations.
48
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As described below for three of the four individual subcategories,
water usage can be eliminated through substitution of alternative
procedures or equipment.
TREATMENT TECHNOLOGY
Included with end-of-pipe treatment technologies are those in-plant
modifications that are more than control measures, e.g., substitu-
tion of dry air pollution control equipment for wet scrubbers. This
is regarded as a logical arrangement because the changes are
separate from the manufacturing processes, major equipment instal-
lation is required, and both relate to protection of environmental
quality through treatment.
Technical Considerations
The recommended control and treatment technologies are believed to
be applicable to the appropriate subcategories, as outlined below,
and are based on the limited data available. It is conceivable that
unknown factors would render a particular technology inoperative at
a given plant. The steps described here cannot, therefore, be
applied without careful analysis of each plant's wastes and
particular requirements.
Application
The control and treatment technologies recommended here can be
applied regardless of plant size and capacity, the manufacturing
process, or plant and equipment age. The design can be altered to
fit the plant's needs, and the wastes from both large and small
plants can be managed efficiently using these technologies.
Land Requirements
All of the recommended control and treatment technologies require
relatively little land area; less than 0.1 hectare (0.25 acre) in
all cases. If more land is available at a given plant, larger
facilities may be employed to reduce operating costs.
The additional land required for disposal of containerized liquid
wastes resulting from the technologies described here are not large.
The waste water volumes are relatively small when compared to many
industries, and the volumes of waste generated for land disposal are
also relatively small.
Compatibility of control Measures
In some categories, the Level I technologies (1977) are based on
treatment to reduce the pollutants to acceptable levels prior to
discharge, while the Level II technologies (1983) involve substi-
tution of equipment so that no waste water is generated. The two
levels are incompatible in that the money spent in implementing the
Level I controls is lost when the Level II controls are installed.
Whether to stop at Level I or move directly to Level II is a
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management decision for each plant. Since half of the plants known
to be generating process waste waters now discharge to municipal
sewerage systems, the decision takes on added dimensions.
INDUSTRY SUBCATEGORIES
The control measures and treatment technologies that are applicable
to the separate subcategories of this part of the asbestos industry
are described below.
Asbestos Textile Coating
The wastes from textile coating result from clean-up and dumping of
unused coating material at the end of a run. The waste waters are
small in volume and relatively concentrated. Because of the high
cost of treating this waste to make it suitable for discharge to a
surface water, the recommended control measure is containment of the
waste in undiluted form and containerization for salvage or land
disposal. The required quantities of finishing material for each
run should be estimated and prepared so that a minimal amount
remains to be disposed of. Dry cleaning techniques should be sub-
stituted for wet methods. Measures should be taken to eliminate or
contain spills and dripped material. The waste should be placed in
appropriate containers, e.g., steel drums, for salvage by a
commercial waste handling firm, if available, or for disposal in a
controlled sanitary landfill. If no commercial handling firm is
available and State or local regulations prohibit disposal of
solvents in sanitary landfills, it may be necessary to employ small
batch incinerators for disposal of the reduced volumes of waste.
Solvent Recovery
At least one plant in this industry recovers solvent without gen-
erating waste water. It is not known if this technique is
applicable at other plants using different solvents. The solvent
recovery waste waters may contain significant organic loads and may
have an elevated temperature.
If the organic material is not refractory, bio-treatment by the
activated sludge process after cooling, as necessary, would be
suitable for meeting the Level I limitations. For the scale of
operations encountered in this industry, i.e., approximately 40
cubic meters (10,000 gallons) per day, the extended aeration
variation would be appropriate. Excess sludge could be removed by a
commercial hauler for disposal at a municipal treatment plant.
In order to meet the Level II limitations, or if the waste is
refractory to bio-treatment, adsorption on activated carbon is
recommended. If properly designed and operated, this process should
reduce the concentrations of organic materials to acceptable levels.
Because of the relatively small volume to be handled, carbon
regeneration by the supplier would probably be more economical than
on-site thermal regeneration.
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In preparing to apply either of the treatment technologies described
above, their suitabilities for a particular waste stream must be
evaluated. There are standardized testing procedures to measure
both the biodegradability and sorptive characteristics of waste
waters. In the event that neither of these technologies is
feasible, more sophisticated processes, such as reverse osmosis, are
available to achieve the desired results.
Vapor Absorption
The waste water from vapor absorption operations resembles that from
solvent recovery in that it contains organic material and has a
negligible suspended solids content. In this industry, however, the
vapor absorption operations are operated intermittently, and bio-
treatment processes are not feasible. All biological facilities
require a reasonably steady inflow of waste to function effectively.
Carbon adsorption should be effective with these wastes, however.
Adjustment of the pH to a lower level would probably be beneficial
to increase the efficiency of the carbon.
Since recovery of the solvent is not a goal in vapor absorption, a
fume incinerator could be substituted to remove the vapor from the
exhaust air. Both direct-fired and catalytic types are available
and either should be suitable for this application. Detailed
information about the design, operation, costs, and applicability of
various types of incinerators is beyond the scope of this report and
is readily available in the technical literature on air pollution
control. The use of an incinerator would eliminate the discharge of
waste water in this subcategory.
Wet Dust Collection
The waste waters from wet dust collectors are amenable to treatment
by sedimentation, with coagulation as necessary. There are no data
available on the efficiency of plain sedimentation, but there is no
reason to believe that it would not be effective.
While the dust particles have a significant organic content, they
are not treatable by such processes as bio-treatment or activated
carbon adsorption. If treatment beyond sedimentation is indicated,
filtration would be the logical next step and complete removal could
be accomplished. A more appropriate means of solving this problem
is to substitute dry dust collectors, e.g., baghouses, for the wet
scrubbers. This step, which is already being taken at some of the
plants in this industry, eliminates the discharge of waste water in
this subcategory. Detailed information about the engineering
aspects of the available equipment for dry collection of
particulates is beyond the scope of this report and is available in
the literature dealing with air pollution control.
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SECTION VIII
COST, ENERGY, AND NON-WATER QUALITY ASPECTS
An analysis of the estimated costs and pollution control benefits of
alternative control and treatment technologies applicable to this
part of the asbestos manufacturing industry is given in this
section.
The cost estimates were developed using data from various sources,
including the contractor's files and the general information on
costs referenced in Section XIII. There was very little useful
treatment cost data available from the industry. The existing
treatment facilities are lagoons of various types and most of them
receive large volumes of waste waters from sources not included in
this report, e.g., spent cooling water or wastes from other
manufacturing processes.
REPRESENTATIVE PLANTS
The representative plants used to develop treatment cost information
are composites rather than actual plants. Because there are so few
plants that generate waste waters, the composites represent all the
known plants in the industry. The treatment technologies were
developed for application to effluents discharged to surface waters,
although half of the plants discharge to municipal sewerage systems.
The costs are based on typical, standard control and treatment
technologies that are either used elsewhere in this industry or are
used with similar wastes from sources outside this industry. The
waste flows were selected as typical for the plants, and where a
significant range of flows exist, estimates for various sizes were
developed.
The end-of-pipe control technologies were designed, for cost pur-
poses, to require minimal space and land area. It is believed that,
at most plants, no additional land would be required. At locations
with more land available, larger, more economical facilities of
equal efficiency may be used, e.g., a lagoon may be substituted for
a mechanical clarifier.
In summary, the cost information is intended to apply to most plants
in this industry. Differences in age or size of production facili-
ties, level of implementation of in-plant controls, and local non-
water quality environmental aspects all reduce to one basic
variable, the volume of waste water discharged. The sizes of the
representative composite manufacturing plants used for the four
subcategories are presented in Table 3. For those subcategories
where dry air pollution control equipment may be substituted,
exhaust air flow rates that correspond approximately to the waste
water flows are given.
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TABLE 3
REPRESENTATIVE MANUFACTURING PLANTS USED IN
DEVELOPING COST ESTIMATES
Waste Water Flow
cu m/day mgd
0.8 0.0002
38 0.01
230** 0.06**
Subcategory
Textile Coating
Solvent Recovery
Vapor Absorption
Wet Dust Collection:
Small
Medium
Large
* NA - Not Applicable
** Total discharge per operating period.
190
380
570
0.05
0.10
0.15
Exhaust Air Flow
cu m/min scfm
NA*
NA
570
NA
NA
20,000
280 10,000
850 30,000
1700 60,000
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COST INFORMATION
The investment and annual costs associated with the alternative
control technologies for the four subcategories, as well as the
effluent quality associated with each alternative, are summarized in
Tables <4 through 9. All costs are reported in August, 1971 dollars.
Investment Costs
Investment costs are defined as the capital expenditures required to
bring the treatment or control technology into operation. Included,
as appropriate, are the costs of excavation, concrete, mechanical
and electrical equipment installed, and piping. An amount equal to
from 15 to 25 percent of the total of the above was added to cover
engineering design services, construction supervision, and related
costs. The lower percentages were used for the larger facilities.
Because most of the control technologies involved external, end-of-
plant systems, no cost was included for lost time due to
installation. It is believed that the interruption required for
installation of control technologies can be coordinated with normal
plant shut-down and vacation periods in most cases. As noted above,
the control facilities were estimated on the basis of minimal space
requirements. Therefore, no additional land costs were included.
Capital Costs
The capital costs are calculated, in all cases, as 8 percent of the
total investment costs. Consultations with representaties of
industry and the financial community led to the conclusion that,
with the limited data available, this estimate was reasonable for
this industry.
Depreciation
Straight-line depreciation was used in all cases. The periods used
were believed to be typical for the particular technology and are
indicated in the footnotes on Tables 4 through 9.
Operation and Maintenance costs
Operation and maintenance costs include labor, materials, solid
waste disposal, effluent monitoring, added administrative expenses,
taxes, and insurance. Manpower requirements were based upon a total
salary cost of $10 per man-hour in all cases. The costs of
chemicals used in treatment were added to the costs of materials
used for maintenance and operation. The costs of solid waste
handling and disposal were based primarily upon information supplied
by the representative firms.
Ener CJY and Power Costs
Energy costs were estimated on the basis of $0.025 per kilowatt-
hour.
55
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CONTROL TECHNOLOGIES WITH COSTS
The estimated costs and the associated reduction benefits for the
alternative control technologies for each of the subcategories are
presented below.
ile Coating (Table U)
Alternative A - No Waste Treatment or Control
Effluent waste load is a very small volume of concentrated organic
material (COD) and suspended solids with potentially significant
levels of heavy metals and plant nutrients. The waste is discharged
on about half of the plant operating days.
Costs. None.
•
Reduction Benefits. None
Alternative B - Zero Discharge
Discharge of waste water is eliminated through in-plant control
measure, including the use of dry cleaning methods and containment
of dumped and spilled coating material. Waste is containerized for
salvage by commercial waste salvage firm or for disposal in a con-
trolled sanitary landfill. Some in-plant control measures are now
in use, e.g., minimizing dumps, but no plant completely retains all
waste.
Costs. Investment cost is approximately $2,000.
Reduction Benefits. Reduction of all pollutant
constituents of 100 percent.
Solvent Recovery (Table 5)
Alternative A - No Waste Treatment or Control
Daily effluent waste load is estimated to be 75 kg (165 Ib) of COD
and 45 kg (100 Ib) of BOD for the typical plant at this minimal
control level. The suspended solids waste load is negligible. All
known plants in the industry provide only this level of control.
Costs. None.
Reduction Benefits. None.
Alternative B - Biological Treatment
This alternative involves using the extended aeration variation
of the activated sludge process with removal of excess sludge to
a municipal sewage treatment plant. The daily effluent waste load
is estimated to be about 2 kg (5 Ib) of COD and 1.1 kg (2.5 Ib)
of BOD with this alternative.
Costs. Investment costs are approximately $73,000.
56
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TABLE h
TYPICAL PLANT
WATER EFFLUENT TREATMENT COSTS
ASBESTOS MANUFACTURING
ASBESTOS TEXTILE COATING
Treatment or Control Technologies:
Investment
Annual Costs:
Capital Costs
Depreciation
Operating and Maintenance Costs
(excluding energy and power costs)
Energy and Power Costs
Total Annual Cost
(Costs in $1000)
A B
2.0
0.2
0.2*
8.0
Zero
8.4
Effluent Quality:
Effluent Constituents
COD - mg/1
Suspended Solids - mg/1
pH - units
* Expected Lifetime
Raw
Waste
Load
Variable
Variable
Variable
10 years.
Resulting Effluent
Levels
Variable
Variable
Variable
Zero
Zero
57
-------
TABLE 5
TYPICAL PLANT
WATER EFFLUENT TREATMENT COSTS
ASBESTOS MANUFACTURING
SOLVENT RECOVERY
Treatment or Control Technologies:
Investment
Annual Costs:
Capital Costs
Depreciation
Operating and Maintenance Costs
(excluding energy and power costs)
Energy and Power Costs
Total Annual Cost
Effluent Quality:
Effluent Constituents
(Costs in $1000)
A B C
73
5.9
2.9*
11.7
10.5**
12.5 20.6
11.0 1.0***
32.3 1*3.8
BOD (5-day) - mg/1
COD - mg/1
Suspended Solids - mg/1
pH - units
* Expected lifetime - 25 years
** Expected lifetime - lU years
*** Not including carbon regeneration.
Raw
Waste
Load
1200
2000
30
6-9
Resulting Effluent
Levels
1200
2000
30
6-9
30
50
30
6-9
5
5
5
6-9
58
-------
Reduction Benefits. Estimated reduction of effluent
COD and BOD of 97 percent.
Alternative C - Carbon Adsorption
This alternative involves treating the effluent from the bio-treatment
process in 2-stage granular activated carbon columns. The carbon
is regenerated off-site by the supplier. Costs for filtration
of the bio-treatment process effluent are not included. The daily
effluent waste load is estimated to be less than 0.2 kg (0.4 Ib)
for both COD and BOD.
Costs. The estimated incremental cost for this
alternative is $146,000. Total costs are $219,000.
Reduction Benefits. Reduction of COD and BOD of
more than 99.8 percent.
Vapor Absorption (Table 6)
Alternative A - No Waste Treatment or Control
Daily effluent waste load is estimated to be 410 kg (900 Ib) of COD
at a pH level above 9.5. The suspended solids waste load is neg-
ligible. Discharge is presently intermittent in this subcategory.
Costs. None.
Reduction Benefits. None.
Alternative B - Carbon Adsorption
This alternative involves treatment of the raw waste water in 2-stage
granular activated carbon columns. The raw waste water is acidulated
as necessary, but does not require filtration. The carbon is regen-
erated off-site by the supplier. The daily effluent waste load is
estimated to be about 10 kg (22 Ib) of COD with the pH value in the
neutral range, 6 to 9.
Costs. Investment cost is estimated to be $130,000.
Reduction Benefits. Reduction of COD of approximately
98 percent and neutralization of alkali in effluent.
Alternative C - Zero Discharge
Zero discharge is achieved by replacement of the vapor absorption
unit with a fume incinerator. No waste water is generated.
Costs. Estimated cost for this alternative is
$152,000.
Reduction Benefits. Reduction of all pollutant
59
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TABLE 6
TYPICAL PLANT
¥ATER EFFLUENT TREATMENT COSTS
ASBESTOS MANUFACTURING
VAPOR ABSORPTION
Treatment or Control Technologies:
Investment
Annual Costs:
Capital Costs
Depreciation
Operating and Maintenance Costs
(excluding energy and power costs)
Energy and Power Costs
Total Annual Cost
(.Costs in $1000)
A B C
130
152
10.H 12.2
9-3* 15.2**
8.7 1.8
1.0*** 16.8
29. U 1*6.0
Effluent Quality:
Effluent Constituents
COD - mg/1
Suspended Solids - mg/1
pH - units
Raw
Waste
Load
1800
30
>9
Resulting Effluent
Levels
1800
30
>9
50
30
6-9
Zero
Zero
* Expected lifetime - 1^ years
** Expected lifetime - 10 years
*** Not including carbon regeneration.
60
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constituents of 100 percent.
Wet Dust Collection (Tables 7, 8, and 9)
Alternative_A - No Waste Treatment or Control
Estimated effluent waste load is 380 cu m (100,000 gal) per day of
concentrated dust slurry. The dissolved solids level is not sig-
nificantly higher than that of the carriage water.
Costs. None.
Reduction Benefits. None.
Alternative B - Sedimentation
This alternative comprises sedimentation, with coagulation as
necessary, to remove suspended solids. Sludge is dewatered for
disposal in a controlled sanitary landfill. Daily effluent waste
load is estimated to be 11 kg (25 Ib) of suspended solids. All
known plants use this alternative as a minimum level of control.
Costs. Investment cost is estimated to be $64,000.
Reduction Benefits. Reduction of suspended solids
of over 95 percent.
Alternatiye^c - Zero Discharge
This alternative comprises substitution of dry dust collection
devices (baghouses) for the wet dust scrubbers. No waste water is
generated in using this control technology. Most of the friction
materials plants now use such dry equipment.
Costs. Estimated investment cost is $94,000.
Reduction Benefits. Reduction of all pollutant
constituents of 100 percent.
ENERGY REQUIREMENTS OF CONTROL TECHNOLOGIES
The energy requirements to implement the control technologies in the
asbestos textile coating subcategory are minimal and relate
primarily to transportation of the containerized waste to a salvage
facility or a sanitary landfill site.
The additional energy required in the solvent recovery category will
also involve energy for transportation of waste sludge away from the
plant and of activated carbon to and from the site. The major
energy requirements will be for pumping and aeration in the bio-
treatment unit and for regeneration of the activated carbon columns.
The former requirement is estimated to be about 7.5 kw (1C hp). The
61
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TABLE 7
TYPICAL PLANT
WATER EFFLUENT TREATMENT COSTS
ASBESTOS MANUFACTURING
WET DUST COLLECTION - SMALL PLANT
Treatment or Control Technologies:
Investment
Annual Costs:
Capital Costs
Depreciation
Operating and Maintenance Costs
(excluding energy and power costs)
Energy and Power Costs
Total Annual Cost
Effluent Quality:
Effluent Constituents
COD (Filtrate) - mg/1
Suspended Solids - mg/1
pH - units
* Expected lifetime - 25 years
** Expected lifetime - 20 years.
(Costs in $1000)
A B C
3.5 3.k
1.8* 1.7**
7.7 k.3
17.0 9.U
Raw
Waste
Load
Unknown
Variable
6-9
Resulting Effluent
Levels
Unknown
Variable
6-9
50
30
6-9
Zero
Zero
^
62
-------
TABLE 8
TYPICAL PLANT
WATER EFFLUENT TREATMENT COSTS
ASBESTOS MANUFACTURING
¥ET DUST COLLECTION - MEDIUM PLANT
Treatment or Control Technologies:
Investment
Annual Costs:
Capital Costs
Depreciation
Operating and Maintenance Costs
(excluding energy and power costs)
Energy and Power Costs
Total Annual Cost
(Costs in $1000)
A B C
6k
5.1
2.6*
12.0
5-2
2k. 9
9k
7.5
6.1
18.3
Effluent Quality:
Effluent Constituents
COD (Filtrate) - mg/1
Suspended Solids - mg/1
pH - units
Raw
Waste
Load
Resulting Effluent
Levels
Unknown Unknown 50
Variable Variable 30
6-9 6-9 6-9
* Expected lifetime - 25 years
** Expected lifetime - 20 years.
Zero
Zero
63
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TABLE 9
TYPICAL PLANT
WATER EFFLUENT TREATMENT COSTS
ASBESTOS MAMJFACTURING
WET DUST COLLECTION - LARGE PLANT
Treatment or Control Technologies:
Investment
Annual Costs:
Capital Costs
Depreciation
Operating and Maintenance Costs
(excluding energy and power costs)
Energy and Power Costs
Total Annual Cost
(Costs in $1000)
A B C
83
6.6
3.3*
16.0
6.5
32.7
11.7
7-3**
8.5
27-5
Effluent Quality:
Effluent Constituents
COD (Filtrate) - mg/1
Suspended Solids - mg/1
pH - units
Raw
Waste
Load
Resulting Effluent
Levels
Unknown Unknown 50
Variable Variable 30
6-9 6-9 6-9
Zero
Zero
* Expected lifetime - 25 years
** Expected lifetime - 20 years.
64
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energy required to regenerate the carbon off-site at the supplier's
facility cannot be estimated without knowing the scale of the
operation. If it is large, the incremental energy required for this
subcategory will not be significant because of the relatively small
carbon requirements.
The energy requirements for implementation of the alternatives for
the vapor absorption subcategory are primarily for fuel to regen-
erate the activated carbon and to operate the fume incinerator. The
requirement for regeneration cannot be estimated for the same reason
as with the solvent recovery subcategory, except that in this case,
about ten times as much carbon is required per year because the
waste is not pretreated by the biological process and also because
no credit is taken for biological activity in the carbon columns.
The energy requirements of the fume incinerator may be relatively
high, but this unit will be operated only one or two days per month.
The fuel requirement depends upon the energy content of the
vaporized solvent.
The energy used in clarifying waste waters from wet dust collection
is not large, 5 kw (6.7 hp) or less for the sludge removal mechan-
isms and no more than 20 kw (25 hp) for pumping. A centrifuge for
dewatering the sludge would require 30 to 40 kw (40 to 53 hp) when
running. The energy requirements for the operation of baghouses
should be less than for wet dust collectors.
No information was provided by the industry relative to the energy
requirements of individual manufacturing plants. Most of the fric-
tion materials plants use large amounts of energy for heating and
curing their products. The additional energy required to implement
the control and treatment technologies is estimated to be less than
10 percent of the requirements for the manufacturing and associated
operations. The major energy uses are for carbon regeneration and
fume incineration.
NON-WATER QUALITY ASPECTS OF CONTROL TECHNOLOGIES
Air Pollution
Three of the four subcategories in this industry relate totally or
partially to control of pollutant emissions to the atmosphere. The
use of the substituted dry control devices would effect equal, or
better, control of the pollutants of interest. The only significant
potential air pollution problem associated with the application of
the control technologies at a typical plant is the release of
materials from improperly managed solid residues. For example,
exposed accumulations of dust from friction materials plants may
serve as sources of air emissions.
There are no significant odor problems associated with implementa-
tion of the waste water control and treatment technologies. Neither
are there any unusual or uncontrollable sources of noise associated
with the control measures.
65
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§2iid Waste Disposal
The volumes of solid wastes resulting from application of the con-
trol technologies will not be large compared to many industries.
The wastes do not present any unusual problems in handling or in
disposal. A properly planned, designed, and operated sanitary
landfill with capability for receiving industrial solid waste will
be adequate. The disposal of dust is already practiced at all known
friction materials plants and implementation of the control
technologies will not create any unusual problems. Transportation
of dust should be in closed vehicles or the dust should be heavily
dampened to eliminate air emissions. The containerized waste from
textile coating does not pose a health or environmental hazard if
properly disposed of at a licensed landfill site.
There is no known recovery value in any of the residues from this
industry with the possible exception of use as fuel substitute. No
data are available by which to evaluate this possibility.
66
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SECTION IX
EFFLUENT REDUCTION ATTAINABLE THROUGH APPLICATION OF THE
BEST PRACTICABLE CONTROL TECHNOLOGY CURRENTLY AVAILABLE
EFFLUENT LIMITATIONS GUIDELINES
INTRODUCTION
The effluent limitations which must be achieved by July 1, 1977, are
to specify the degree of effluent reduction attainable through the
application of the Best Practicable Control Technology Currently
Available. Best Practicable Control Technology Currently Available
is generally based upon the average of the best existing performance
by plants of various sizes, ages, and unit processes within the
industrial category or subcategory. This average is not based upon
a broad range of plants within an indsutry, but instead upon
performance levels achieved by exemplary plants.
Consideration must also be given to:
a. The total costs of application of this control
technology in relation to the effluent reduction
benefits to be achieved from such application,
b. energy requirements,
c. non-water quality environmental impact,
d. the size and age of equipment and facilities involved,
e. the processes employed,
f. process changes, and
g. the engineering aspects of the application of this
control technology.
Best Practicable Control Technology Currently Available emphasizes
treatment facilities at the end of a manufacturing process, but also
includes the control technologies within the process itself when the
latter are considered to be normal practice within an industry.
A further consideration is the degree of economic and engineering
reliability which must be established for the technology to be
"currently available". As a result of demonstration projects, pilot
plants, and general use, there must exist a high degree of
confidence in the engineering and economic practicability of the
technology at the time of commencement of construction or in-
stallation of the control facilities.
EFFLUENT REDUCTION ATTAINABLE THROUGH THE APPLICATION OF BEST
PRACTICABLE CONTROL TECHNOLOGY CURRENTLY AVAILABLE
67
-------
TABLE 10
EFFLUENT REDUCTION ATTAINABLE THROUGH APPLICATION
OF BEST PRACTICABLE CONTROL TECHNOLOGY CURRENTLY
AVAILABLE*
Subcategory
Solvent Recovery
Textile Coating
Vapor Absorption
Wet Dust Collection
COD
mg/1
50
zero
NA
Suspended Solids
mg/l pH
30 6-9
No discharge of process wastes
zero 6-9
30 6-9
*Maximum average of daily values for any period
of 30 consecutive days.
68
-------
Based on the information contained in Sections III through VIII of
this document, it has been determined that the degrees of effluent
reduction attainable through the application of the Best Pollution
Control Technology Currently Available for this part of the asbestos
manufacturing industry are those presented in Table 10. These
values represent the maximum allowable average for any 30
consecutive calendar days. Maximum daily averages should not exceed
twice the 30-day values.
Oxygen-Demanding Materials
Waste waters from the solvent recovery and vapor absorption sub-
categories normally contain significant quantities of dissolved
organic materials that exert an oxygen demand. While some of these
organic components are biodegradable, others are not. The BOD test
is, therefore, of limited value, and the COD (or TOC) parameter is
recommended. Application of control technology will reduce the
concentrations of oxygen-demanding materials by at least 97 percent.
Suspended Solids
Suspended solids are the principal pollutant constituent in waste
waters from the wet dust collection subcategory. Application of
control technology will reduce the suspended solids to levels
comparable to those achieved in the secondary treatment of municipal
waste waters.
EH
The pH level of all waste waters should be in the neutral range from
6 to 9 upon application of this control technology.
IDENTIFICATION OF BEST PRACTICABLE CONTROL TECHNOLOGY CURRENTLY
AVAILABLE
The Best Practicable Control Technology Currently Available com-
prises in-plant measures for the textile coating subcategory and
end-of-pipe treatment technologies for the solvent recovery, vapor
absorption, and wet dust collection subcategories
Textile coating
The control technology comprises elimination of discharge con
tainment of dumped and spilled coating materials, dry techniques for
cleaning of equipment and for housekeeping, and institution of water
conservation practices to minimize the volume of waste. All wastes
are containerized for salvage, use as a fuel substitute, or disposal
in a controlled sanitary landfill. Although this control technology
is not practiced within this subcategory, it is believed to be much
less costly than providing treatment to render the waste waters
suitable for discharge to a surface water.
69
-------
Solvent Recovery
indicates that they are amenable to biological treatment
Vapor Absorption
IS
= afp^-upi-i-crce control technology.
Wet Dust Collection
For the wet dust
f"bcate?ory, the control technology
TECHNOLOGY
Total Costs of Application
S
annual costs for all of the known manufacturing plants in thl ?our
subcategones are estimated to be $150,000.
Energy Requirements
The most significant energy requirement is fn«=i for- -F» «
xncxneration in the vapor absorption subcaSgSry. sSce there Ts
only one known plant in this subcategory, the additional SnerJv
required 1S not large for the industry as a whole othe? eneraJ
SSSSTf 8 ' ^^Ude ,th°Se f°r PUmP±ng °f ^e wlste Satlrs lo the
treatment facilities, for aeration of bio-treatment processes and
for transportation of wastes and activated carbonf A?l ol'thSe
70
-------
requirements will not increase the level of energy consumption at a
typical plant by more than 5 percent.
Non-Water Quality Environmental Impact
There is no evidence that application of this control technology
will result in any unusual air pollution, noise, radiation, or solid
waste management problems, either in kind or magnitude. The costs
of avoiding problems in these areas are not excessive. The
principal area for attention is the disposal of solid wastes;
sludges, slurries, and other residues.
Size and Age of Equipment and Facilities
Differences in size and age of the manufacturing equipment and
facilities do not influence the applicability of this control
technology.
Processes Employed
There is no information available to indicate that the control
technology cannot be applied to some plants because of the processes
employed. However, each plant is unique, and an individual
evaluation is required at each location to determine the suitability
of the control technology and define any necessary modifications.
Changes
No changes in the manufacturing processes are required to implement
this control technology. There are no anticipated changes in
production methods in any of the four subcategories that would
lessen the effectiveness of the control technology. Solvent changes
can be compensated for by over-design of the carbon units or by
changes in their operation.
Engineering Aspects of Application
Outside of the wet dust collection subcategory, this level of con-
trol has not been applied in this industry. The recommended in-
plant control measures and end-of-pipe treatment technologies have
been widely applied in other industrial settings, however, and no
technical difficulties are anticipated. As noted elsewhere, the
data base for this document is not extensive, and evaluation of each
plant's particular wastes is necessary before implementing any
control measure. Of particular interest would be the bio-
degradability of waste waters from solvent recovery facilities and
the sorptive properties of wastes from wet vapor scrubbing
operations. The need for coagulation should be evaluated for the
waste waters from wet dust collectors.
71
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SECTION X
EFFLUENT REDUCTION ATTAINABLE THROUGH APPLICATION OF
THE BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE
EFFLUENT LIMITATIONS GUIDELINES
INTRODUCTION
The effluent limitations that must be achieved July 1, 1983, are to
specify the degree of effluent reduction attainable through the
application of the Best Available Technology Economically
Achievable. This control technology is not based upon an average of
the best performance within an industrial category, but is
determined by identifying the very best control and treatment
technology employed by a specific plant within the industrial
category or subcategory, or that is readily transferable from one
industry to another:
Consideration must also be given to:
a. The total cost of application of this control
technology in relation to the effluent reduction
benefits to be achieved from such application,
b. energy requirements,
c. non-water quality environmental impact,
d. the size and age of equipment and facilities involved,
e. the processes employed,
f. process changes, and
g. the engineering aspects of the application of this
control technology.
The Best Available Technology Economically Achievable also considers
the availability of in-process controls as well as in-plant control
measures and additional end-of-pipe treatment techniques. This
control technology is the highest degree that has been achieved or
has been demonstrated to be capable of being designed for plant
scale operation up to and including "no discharge" of pollutants.
Although economic factors are considered in this development, the
costs for this level of control are intended to be the top-of-the-
line of current technology subject to limitations imposed by
economic and engineering feasibility. However, this control
technology may be characterized by some technical risk with respect
to performance and with respect to certainty of costs. Therefore,
the control technology may necessitate some industrially sponsored
development work prior to its application.
EFFLUENT REDUCTION ATTAINABLE THROUGH APPLICATION OF THE BEST
AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE
Based upon the information contained in Sections III through VIII of
this document, a determination has been made that the degrees of
effluent reduction attainable through the application of the Best
73
-------
TABLE 11
EFFLUENT REDUCTION ATTAINABLE THROUGH APPLICATION
OF BEST AVAILABLE TECHNOLOGY ECONOMICALLY
ACHIEVABLE*
Subcategory
Solvent Recovery
Textile Coating
Vapor Absorption
Wet Dust Collection
COD
mg/1
Suspended Solids
pH
6-9
No discharge of process wastes
No discharge of process wastes
No discharge of process wastes
*Maximum average of daily values for any period
of 30 consecutive days.
74
-------
Available Technology Economically Achievable are those listed in
Table 11. The values given for the solvent recovery subcategory are
the maximum allowable averages for 30 consecutive days. Maximum
daily values should not exceed three times the 30-day averages.
Oxygen-Demanding Materials
Application of this control technology will reduce the concentration
of oxygen-demanding materials in the raw waste waters from the
solvent recovery subcategory by at least 99.5 percent.
Suspended Solids
The suspended solids in the raw waste waters from solvent recovery
facilities should be negligible. Application of this control
technology will not increase the discharge of suspended solids
significantly, although dissolved organics are converted into
suspended solids within the biological treatment process employed as
the first step.
EH
The waste waters discharged following application of this control
technology will have pH values in the neutral range of 6 to 9.
IDENTIFICATION OF BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE
The Best Available Technology Economically Achievable comprises the
installation of advanced end-of-pipe treatment technology in the
solvent recovery subcategory and substitution of a different type ot
in-plant air pollution control equipment in the wet dust collection
subcategory.
Textile Coating
The control technology for the textile coating subcategory is the
same as the Best Practicable Technology Currently Available as
presented in Section IX. No additional control is required.
Solvent Recovery *
The control technology is activated carbon treatment of the effluent
from the biological treatment process identified as Best Practicable
Technology Currently Available. With proper operation of the bio-
treatment unit, filtration of the effluent may not be necessary.
Because of the relatively small scale of the treatment facility, the
carbon is regenerated off-site, probably by the supplier.
Vapor Absorption
No discharge of process wastes is achieved in this subcategory by
use of a fume incinerator to oxidize the vapors in the air exhausted
from the drying oven.
75
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Wet Dust Collection
reDlac^°i ^hn^y for the ™* dust collection subcategory is
replacement of the wet scrubbers with baghouses or other dry
particulate collection devices of equal efficiency. No was?e wate?
is generated with this control technology.
RATIONALE FOR THE SELECTION OF BEST AVAILART V T^HMOTrv-v
ECONOMICALLY ACHIEVABLE AVAILABLE TECHNOLOGY
Costs of Application
^-inT^ry^^
tnfeSti°Lef^r^uLh\fl??r??o\fnPa0^?ont%rtlUrfaCerLrS'
S/'SSSS *? BeSt ?aCti""4 ?~"n°?°£ Cu£entlVTailaliee?
""charge tf™nicH sISL?StlS ^^^"^tSufS
for this control technolSgyeis9eS?imatea'tohbeacloserlntoStJ600 000*
Jnnf^? *a\, c°mbfned. cost f°r implementation of both levels of
£2£? technologies is estimated to be about $800,000, with the
total annual costs estimated to be about $225,000 for th4 industry.
Energy Requirements
Application of this control technology will require additional
energy for carbon regeneration in the solvent recover^ subcategory
?he L~ 11 Subcate9°rv includes only a very small number of — Y*
be%?^alLnr^len^Li^6arthe tota?nergY re^1'«"«t«
-co -cne total energy requirement
Non-Water Quality Environmental Impact
-
t.,
plants! ° particulates Produced in friction materials manufac?urSg
Size and Ac[e of Equipment and Facilities
fci and, age of the manufacturing equipment and
technology". influence the applicability of \his control
76
-------
Processes. Employed
Since this control technology is entirely related to auxiliary
operations and not to the manufacturing processes, it can be applied
without particular regard to the processes employed.
£E°£J=i2.§ Changes
For the reason noted in the previous paragraph, application of this
control technology does not require any changes in any of the
manufacturing processes in any subcategory of this industry. Any
normal process changes would not lessen the effectiveness of the
control technology. If different solvents were used, the operation
of the fume incinerator and the activated carbon units can be
modified to compensate for the changes.
Engineering Aspects of Application
Although no insurmountable problems are anticipated in applying this
control technology, an engineering evaluation will be necessary
prior to implementation in each plant in the solvent recovery
subcategory. If carbon adsorption should not be effective, more
sophisticated processes, e.g., reverse osmosis, might be necessary
to meet the recommended effluent limitations. In the design of a
fume incinerator, the engineer must consider the auxiliary energy
requirement, if any, and the potential for toxic by-products, such
as the generation of phosgene in the burning of trichloroethylene.
Application of the recommended control technology in the wet dust
collection subcategory has already been widely demonstrated and no
unusual engineering problems should arise.
77
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SECTION XI
NEW SOURCE PERFORMANCE STANDARDS
INTRODUCTION
Defined standards of performance are to be achieved by new sources
of waste waters. The term "new source" is defined to mean "any
source, the construction of which is commenced after the publication
of proposed regulations prescribing a standard of performance".
In defining performance standards for new sources, consideration
must be given to:
a. costs and energy requirements,
b. Non-water quality environmental impact, and
c. Process and other operational changes.
EFFLUENT QUALITY ACHIEVED THROUGH IMPLEMENTATION OF NEW SOURCE
PERFORMANCE STANDARDS
Implementation of New Source Performance Standards will result in
the recommended effluent qualities given in Table 12. The values
for the solvent recovery subcategory are the maximum allowable
averages for 30 consecutive days. Maximum daily values should not
exceed twice the 30-day averages.
Pollutant Constituents
Implementation of the new source performance standards in the
solvent recovery subcategory should reduce all pollutant constitu-
ents to levels comparable to secondary treatment of municipal
sewage.
IDENTIFICATION OF NEW SOURCE PERFORMANCE STANDARDS
In the design and operation of new manufacturing facilities, in-
plant controls and end-of-pipe technology will be required to meet
the recommended standards.
Textile coating
New sources in the textile coating subcategory should be designed
and built to contain all wastes. Such design and operation will
involve minimal additional construction costs and only moderate
annual costs. Added energy requirements will be negligible. If
properly disposed of in a controlled sanitary landfill, this in-
plant measure should not create any pollution problems. Initially,
consideration should be given to recovery and reuse of the coating
material instead of land disposal.
79
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TABLE 12
STANDARDS OF PERFORMANCE FOR NEW SOURCES*
Subcategory
Solvent Recovery
Textile Coating
Vapor Absorption
Wet Dust Collection
COD
mg/1
50
Suspended Solids
rng/1 pH
30 6-9
No discharge of process wastes
(Subcategory eliminated)
(Subcategory eliminated)
*Maximum average of daily values for any period
of 30 consecutive days.
80
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Solvent Recovery
The use of biological treatment is recommended to meet the new
source performance standards in the solvent recovery subcategory.
This end-of-pipe technology may require cooling and addition of
supplemental nutrients, but is the least costly means of reducing
the organic concentrations in the waste water. If this method is
not feasible, carbon adsorption, reverse osmosis, or other advanced
treatment technology may be used. The energy requirements are small
for bio-treatment, but increase for the more advanced processes.
Solvent recovery provides a means of conserving material resources
and eliminating air pollution. The benefits derived must be
balanced against the increased use of energy resources.
Va^or Absorption
It is recommended that vapor or fume emissions in all new sources be
either recovered for reuse or as fuel substitutes or be removed from
the exhaust air stream by means other than absorption in water.
Several alternative technologies that do not generate waste waters
are available. The costs and energy requirements for such
alternatives will probably be higher than for a wet scrubber,
however.
Wet Dust collection
It is recommended that dust, or particulate, emissions in all new
sources be controlled by baghouses or other, equally effective, dry
collection devices. These have proven to be somewhat more effective
than wet scrubbers in this industry, and no waste water is
generated. The costs and energy requirements are comparable to wet
collection. The use of dry devices does not create any unusual non-
water quality environmental problems.
Dispersion Process
As noted in Sections IV and V of this document, an additional
subcategory may be created if the dispersion process for making
asbestos yarn becomes operational in this industry. This process is
now in the developmental stages in two plants in the country and it
is known that waste waters are generated. The scale of operations
are too limited to permit definition of the possible control
technologies and standards of performance for these potential new
sources. It can be predicted, however, that in-plant control
measures to conserve water and materials as well as end-of-pipe
treatment technology to reduce the organic load; suspended solids;
and, possibly, heavy metals, hexane extractables, and plant
nutrients will be required. The effluent limitations and the
feasibility of "no discharge" of pollutants will have to be
determined in the future.
81
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SECTION XII
AC KNOWLEDGMENTS
The Environmental Protection Agency wishes to acknowledge the
contributions to the project of Svedrup & Parcel and Associates,
Inc., St. Louis, Missouri. Dr. James Buzzell and his associates
conducted the detailed technical study and drafted the initial
report on which this document is based.
Appreciation is extended to many people in the asbestos manufactur-
ing industry, especially those persons with the companies listed in
Table 1 of this document who cooperated in providing information and
data for this study.
A special word of thanks is due the following company representa-
tives:
Mr. Ernest C. Bratt and Mr. Larry E. Moody of Thermoid Division
of H. K. Porter Company, Inc.
Mr. Issac H. Weaver and Mr. Herman F. Anspach of Raybestos-Manhattan
Inc.
Mr. W. D. Crawford, Mr. Barney Philpot, Mr. Buel Garden,
Mr. Sid Faress, and Mr. Robert Briggs of Uniroyal Fiber
and Textile Division of Uniroyal, Inc.
The assistance of Mrs. Doris Fagan of the Asbestos Textile
Institute, Mr. Brent Farber, Jr., of the Fluid Sealing Association,
and Mr. E. W. Drislane of the Friction Materials Standards Institute
is also gratefully acknowledged.
A lasting indebtedness is acknowledged to those in the Environmental
Protection Agency who assisted in the project from inception of the
study through preparation and review of this document. Especially
deserving recognition are: Ms. Bobby Wortman, Robert Carton, Arthur
Mallon, and Richard Stevenson.
83
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SECTION XIII
REFERENCES
1 Anon., "Asbestos Health Question Perplexes Experts", Chemical
R_Engineerina News, p. 18, December 10, 1973
2. Asbestos, Stover Publishing Company, Willow Grove, Pennsylvania
3. Blecker, H. G., et al.. Capital and Qperatinq_Costs_of
Pollution con trol_ Equipment Modules, 2 Vols., No.
EPA-R5-73-023, (a and b) , U.S. EPA, July, 1973
4. Bowles, O., The_Asbestos_Industry., U.S. Bureau of Mines,
Bulletin 552
5. Clifton, Robert A., "Asbestos", Bureau of Mines_Mjn|rals
Yearbook, U.S. Department of the Interior, 1971
6. Daniel son, J. A. Ed., Air_]PoUjry:oj^Enainee^in3_Manual,
U.S. Department of Health, Education and Welfare,
Public Health Service, No. 999-AP-40, Cincinnati, Ohio, 1967
7. Development Document for Proposed Effluent Limitations Guide-
lines and New Source Performance Standards for the
Building, Construction, and Paper Segment of the
Asbestos Manufacturing Point Source Category, No.
EPA 440/1-73/017, U.S. EPA, October, 1973
8. DuBois, Arthur B. , Airborne Asbestos, U.S. Department
of Commerce, 1971
9. HandbQOk_gf_Asbestos Textiles , 3rd Ed., Asbesots Textile
Institute, Willow Grove, Pennsylvania, 1967
10. impact of Proposed OSHA^Standards_for_Asbestos , report to
U.S. Department of Labor by Arthur D. Little, Inc., 1972
11. Industriaa^W£ste_S^udv._ReEor^^lat^^
Gypsum, and Asbestos Industries, report to Environmental
Protection Agency by Sverdrup & Parcel and Associates, Inc.,
1971
12. Knapp, Carol E. , "Asbestos, Friend or Foe?", Environmental
science and Techno logy. Vol. 4, No. 9, 1970
13. May, Timothy C. , and Lewis, Richard W. , "Asbestos", Bureau
of Mines Bulletin 650X Mineral Facts and Problems ,
uTs. Department of the Interior, 1970
14. Mccrone, W. C., and Stewart, I. M. , "Asbestos", American
Laboratory, p. 13, April, 1974
85
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15. McDermott, James H. , "Asbestos in Water", Memorandum to
Regional Water Supply Representatives. U.S. Environmental
Protection Agency, April 2U, 1973
16. McDonald, J. Corbett, McDonald, Alison D. , Giffs, Graham W. ,
Siemiatycki, Jack and Rossiter, M. A., "Mortality in the
Crysotile Asbestos Mines and Mills of Quebec", Archive
of Environmental Health r Vol. 22, 1971
17. Measurement of Airborne Asbestos Fiber by the Membrane
Filter Method, Asbestos Textile Institute, Willow
Grove, Pennsylvania, 1971
1 8 • Methods for Chemical Analysis of Water and Wastes ,
Environmental Protection Agency, National Environmental
Research Center, Analytical Quality Control Laboratory,
Cincinnati, Ohio, 1971
19 • National Inventory of Sources and Emissions; Cadmium,,
and Asbestos, report to National Air Pollution Control
Administration, Department of Health, Education and
Welfare, by W. E. Davis S Associates, 1970
20 • Occupational Exposure to Asbestos - Criteri^a_ __
Standard, U.S. Department of Health, "Education and
Welfare, Public Health Service, HSM 72-10267, 1972
21. Patterson, W. L. and Banker, R. F. , Estimating costs and
Manpower Requirements for convent- inn a i wac+oMa-i-OT-
Treatment Facilities. Black and Veatch, Consulting
Engineers for the Office of Research and Monitoring,
Environmental Protection Agency, 1971
22. Rosato, D. V., Asbestos: Its Industrial Appli cat ions r
Reinhold Publishing Corporation, New York, New York, 1959
23. Sawyer, G. N. and Mccarty, P. L. , Chemistry for Sanitary
Engineers. 2nd Ed., McGraw-Hill Book Company,
New York, 1967
24. Selikoff, Irving J., Hammond, E. Cuyler and Seidman, Herbert,
Canc^r_Rj^^f_^^j^ti^n_Wprkers_in_the United States.
International Agency for Research on Cancer, 1972
25. Selikoff, Irving J., Nicholson, William J. and Langer,
Arthur M. , "Asbestos Air Pollution", Archives of
Environmental Health r Vol. 25, American Medical
Association, 1972
2 6 . Sewage Treatment Plant and Sewer Construction Cost Indexes ,
Environmental Protection Agency, Office of Water Programs
Operations, Municipal Wastewater Systems Division,
Evaluation and Resource Control Branch
86
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27. Sinclair, W. E. , Asbestos, Its.Qrigin^Production and
Utilization, London, Mining Publications Ltd., 1955
28 Smith, Robert, £v^*_of_cgnventional and Advanced_Treatment
of wastewaters. Federal Water Pollution Control
Administration, U.S. Department of the Interior, 1968
29. Smith, Robert and McMichael, Walter F. , Cost and_,Performance
Estimates for Tertiary Was tewater Treating Processes ,
Federal Water Pollution control Administration, U.S.
Department of the Interior, 1969
30 Standard M^hn^s fQr the ExaminatiQn_Qf_Water_and_Wastewater,
-- 13th Ed.,"American Public Health Association, Washington,
D.C., 1971
31. Sullivan, Ralph J. , Air_Pollution_As£ects_of .Asbestos,
U.S. Department of Commerce, 1969
32. Tabershaw, I. R., "Asbestos as an Environmental Hazard",
journal of Occupational Medicine , 1968
33. The Asbestos Factbook, Asbestos, Willow Grove, Pennsylvania,
1970
34. Villecro, M. , "Technology, Danger of Asbestos", Architectural
Forum, 1970
35. Wright, G. W. , "Asbestos and Health in 1969", American
w of Respiratory Diseases, 1969
87
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SECTION XIV
GLOSSARY
Those terms in this document that have special definitions within
the asbestos manufacturing industry or the water pollution control
field are presented here for the convenience of the reader.
Technical terms not included here are explained in standard
dictionaries.
1. "Act" - The Federal Water Pollution Control Act Amendments
of~~1972.
2. Absorption - the process of taking up or assimilating a gas
or a liquid, specifically, the solution of a vapor in water.
3. Adsorption - the adhesion in an extremely thin layer of
molecules to the surfaces of solid bodies, specifically
activated carbon particles.
H. Asbestos - not a distinct mineral species, but a commercial
term applied to fibrous varieties of several minerals
differing widely in chemical composition and in fiber
length, strength, and flexibility. Varieties include:
Chrysotile - a hydrated magnesium silicate that is
the most abundant and the most important of the
commercial mineral fibers.
Crocidolite - a complex silicate of iron, magnesium, and
sodium that is especially resistant to acid attack.
Amosite - a ferrous silicate in which some of the iron
is replaced by magnesium. It is the longest of all
asbestos fibers and is more resistant to heat than
the two varieties above.
5. Baghouse - a structure housing tubular or envelope-shaped
bags that filter dust and particulate matter from an air stream.
6. Category and Subcategory - divisions of a particular industry
possessing different traits that affect waste water charac-
teristics and treatability.
7. Coating - the application of various finishing materials to
textiles to improve their properties and/or to minimize air
emissions during fabrication and use.
8. Chemical Oxygen Demand (COD) - an indirect measure of the
organic material present in a water sample. Most organic
compounds are measured in this analysis.
9. Dissolved Solids - the amount of material remaining after a
89
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filtered water sample is evaporated to dryness at 103C.
10. Doctor Blade - a sharp blade for wiping excess material from
a surface.
11. Dust Scrubber - a device for removing particulate matter from
an air stream by collecting it in water.
12. Friction Materials - a group of products including brake linings, <
brake blocks, clutch facings, and related items.
13. Fume Incinerator - an air pollution control device that
thermally oxidizes combustible aerosols, gases, or vapors,
sometimes termed an afterburner.
14. Fume Scrubber - an air pollution control device that removes
pollutant constituents from an air stream by dissolving them
in a liquid solvent, specifically water.
15. Hexane Extractables - materials in a water sample that
respond to analytical procedures designed to measure grease,
oil, and similar materials.
16. MBAS - abbreviation for Methylene Blue Active Substances.
These are the anionic surfactants, or synthetic detergents.
17. New source - any source of waste water, the construction of
which is commenced after publication of the proposed regula-
tions prescribing a standard of performance.
18. Organic Materials - carbon-containing compounds manufactured in
the life processes of plants and animals, or synthetically. They
can be oxidized to carbon dioxide, water, and other simple inor-
ganic compounds.
19. pH - a measure of the relative acidity or basicity of a water.
20. Sealing Devices - gaskets, packings, seals, washers, and
similar items, specifically those that contain asbestos.
21. Suspended Solids - non-filterable solids in a water sample, i.e.,
those materials not in solution.
22. Textiles - specifically asbestos yarn, cord, rope, thread, tape,
wick, cloth, and non-woven felts.
23. Total Organic Carbon (TOC) - the result of a high temperature cata-
lytic oxidation procedure for measuring organic materials in water.
90
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TABLE 13
MULTIPLY (ENGLISH UNITS)
ENGLISH UNIT ABBREVIATION
acre ac
acre - feet ac ft
British Thermal
Unit BTU
British Thermal
Unit/pound BTU/lb
cubic feet/minute cfm
cubic feet/second cfs
cubic feet cu ft
cubic feet cu ft
cubic inches cu in
degree Fahrenheit °F
feet ft
gallon gal
gallon/minute gpm
horsepower hp
inches in
inches of mercury in Hg
pounds lt>
million gallons/day mgd
mi 1e nri
pound/square
inch (gauge) psig
square feet sq ft
square inches sq in
ton (short) ton
yard yd
METRIC TABLE
CONVERSION TABLE
by TO OBTAIN (METRIC UNITS)
CONVERSION ABBREVIATION METRIC UNIT
0.405
1233.5
0.252
ha
cu m
kg cal
0.555
0.028
1.7
0.028
28.32
16.39
0.555(°F-32)*
0.3048
3.785
0.0631
0.7457
2.54
0.03342
0.454
3,785
1.609
kg cal/kg
cu m/min
cu m/min
cu m
1
cu cm
°C
m
1
I/sec
kw
cm
atm
kg
cu m/day
km
(0.06805 psig +1)* atm
0.0929
6.452
0.907
0.9144
sq m
sq cm
kkg
m
hectares
cubic meters
kilogram - calories
kilogram calories/kilogram
cubic meters/minute
cubic meters/minute
cubic meters
1i ters
cubic centimeters
degree Centigrade
meters
liters
liters/second
killowatts
centimeters
atmospheres
kilograms
cubic meters/day
kilometer
atmospheres (absolute)
square meters
square centimeters
metric ton (1000 kilograms)
meter
* Actual conversion, not a multiplier
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