Development Document for Effluent Limitations Guidelines
BUILDING, CONSTRUCTION,
AND PAPER
Segment of the Asbestos
Manufacturing
Point Source Category
FEBRUARY 1974
U.S. ENVIRONMENTAL PROTECTION AGENCY
\ ^1/ ? Washington, D.C. 20460
-------
DEVELOPMENT DOCUMENT
for
EFFLUENT LIMITATIONS GUIDELINES
. and
NEW SOURCE PERFORMANCE STANDARDS
for the
BUILDING, CONSTRUCTION AND PAPER SEGMENT OF THE ASBESTOS
MANUFACTURING POINT SOURCE CATEGORY
Russell Train
Admi ni strator
Roger Strelow
Acting Assistant Administrator for Air & Water Programs
Allen Cywin
Director, Effluent Guidelines Division
Robert J. Carton
Project Officer
February 1974
Effluent Guidelines Division
Office of Air and Water Programs
U. S. Environmental Protection Agency
Washington, D. C. 20460
For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 - Price $1.70
-------
ABSTRACT
This document presents the findings of an extensive study of a
segment 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 which is achievable through the application
of the best available demonstrated control technology, processes,
operating methods, or other alternatives.
The development of data and recommendations in the document
relate to a portion of the asbestos manufacturing category which
contains the major water users in this industry. This segment
was subdivided by process into seven subcategories Separate
effluent limitations were developed for each subcategory on the
basis of the level of raw waste loads as well as the degree of
treatment achievable by suggested model systems. These systems
include coagulation, sedimentation, skimming, neutralization, and
certain in-plant modifications.
Supportive data and rationale for developments of the proposed
effluent limitations guidelines and standards of performance are
contained in this report.
ill
-------
TABLE OF CONTENTS
SECTION
I Conclusions
II Recommendations
III Introduction
Purpose and Authority
Summary of Methods
Sources of Data
General Description of Industry
Manufacturing Locations
Manufacturing Processes
Asbestos-Cement Products
Asbestos Paper
Asbestos Millboard
Asbestos Roofing
Floor Tile
Current Status of Industry
IV Industry categorization
Introduction and Conclusions
Factors Considered
V Water Use and Waste Characterization
Introduction
Asbestos-Cement Pipe
Asbestos-Cement Sheet
Asbestos Paper
Asbestos Millboard
Asbes-tos Roofing
Asbestos Floor Tile
VI Selection of Pollutant Parameters
selected Parameters
Major Pollutants
Other Pollutants
VII Control and Treatment Technology
Introduction
In-Plant Control Measures
Treatment Technology
PAgE
1
5
6
7
13
14
19
19
26
30
33
35
37
39
39
39
43
43
45
47
49
51
52
54
57
57
58
60
67
67
68
72
-------
VIII Cost, Energy, and Non-Water Quality Aspects
77
Representative Plants
cost information
Treatment or Control Technologies
Energy Requirements
Non-Water Quality Aspects
IX Best Practicable Technology Currently Available
Effluent Limitations Guidelines
Introduction
Effluent Reduction Attainable
Identification of Control Technology
Rationale for selection
X Best Available Technology Economically Achievable
Effluent Limitations Guidelines
Introduction
Effluent Reduction Attainable
Identification of Control Technology
Rationale for Selection
XI New Source Performance Standards
Introduction
Identification of standards
Effluent Reduction Attainable
Rationale for Selection
XII Acknowledgments
XIII References
XIV Glossary
CONVERSION TABLE
84
77
78
80
96
99
101
101
102
103
105
113
113
114
114
114
123
123
123
124
124
129
131
133
135
Vi
-------
FIGURES
NUMBER
1
2
3
Asbestos-Cement Sheet Manufacturing Operations,
Dry Process
Asbestos-Cement Sheet Manufacturing Operations,
Wet Process
Asbestos-Cement Sheet Manufacturing Operations,
Wet Mechanical Process
Asbestos-Cement Pipe Manufacturing Operations,
Viet Mechanical Process
Asbestos Paper Manufacturing Operations
Asbestos Millboard Manufacturing Operations
Asbestos Roofing Manufacturing Operations
Asbestos Floor Tile Manufacturing Operations
Water Balance Diagram for a Typical
Asbestos-Cement Pipe Plant
Cost Curve for Typical Plants
PAGE
21
22
23
25
28
32
34
36
44
10
11
12
13
14
15
Asbestos-Cement Pipe
Asbestos-Cement Sheet
Asbestos Paper
Asbestos Millboard
Asbestos Roofing
Asbestos Floor Tile
83
86
89
92
95
98
Vii
-------
Number
1
2
3
4
5
6
7
8
9
10
TABLES
Manufacturing Facilities by Subcategory
Locations of Asbestos Plants
Representative Plants
Water Effluent Treatment Costs
Asbestos-Cement Pipe
Asbestos-Cement Sheet
Asbestos Paper
Asbestos Millboard
Asbestos Roofing
Asbestos Floor Tile
Conversion Table
Page
8
15
79
82
85
88
91
94
97
135
viii
-------
SECTION I
CONCLUSIONS
That part of the asbestos manufacturing industry covered in this
document is classified into seven subcategories. The major
factors in subcategorizing the asbestos products industry on the
basis of product lines were raw waste loads and volumes of waste
waters. Other factors further supported this decision, such as
differences in in-plant processes, end-of-pipe control
technologies, and the speed with which zero discharge could be
realized for each subcategory.
The subcategories are as follows:
1. Asbestos-cement pipe,
2. Asbestos-cement sheet,
3. Asbestos paper (starch binder),
U. Asbestos paper (elastomeric binder),
5. Asbestos millboard,
6, Asbestos roofing products, and
7. Asbestos floor tile.
Recommended effluent limitations and waste control technologies
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 less than $3 million, excluding costs of additional
land acquisition. The cost of achieving the 1983 level is
estimated to be about $6 million for the industry, i.e., an
additional $3 million over the 1977 level.
-------
-------
SECTION II
R ECOMMENDATIONS
The recommended effluent limitations for the parameters of major
significance are summarized below for the categories of asbestos
products included in this document. Using the best practicable
control technology currently available, the limits are as
follows:
Suspended
solids
~~kg/kkg*
COD
kg/kkg*
Asbestos-cement pipe
Asbestos-cement sheet
Asbestos paper (starch binder)
Asbestos paper (elastomeric binder)
Asbestos millboard
Asbestos roofing
Asbestos floor tile
0.19
0.23
0.35
0.35
zero discharge
0.006 0.008
0.04** 0.09**
pH between the limits of 6.0 to 9.0 for all subcategories
*kg of pollutant/kkg of product
**Units: kilogram per 1,000 pieces (12"x12flx3/32")
Using the best available control technology economically
achievable, no discharge of waste waters to navigable water is
recommended as the effluent limitation guideline and standard of
performance for all of the above categories of asbestos products.
With the exception of asbestos-cement pipe and asbestos paper
containing elastomeric binders, this limitation and standard of
performance is recommended for all new point sources. These two
excepted products should meet the limitations outlined as best
practicable control technology currently available.
A more detailed explanation of these limitations including daily
maximum limitations are contained in Section IX.
-------
-------
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 defined 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 regulations
issued by the Administrator pursuant to Section 304(b) to the
Act. Section 306 of the Act requires the achievement by new
sources of a Federal standard of performance providing for the
control of the discharge of pollutants which reflects the great-
est degree of effluent reduction which the Administrator
determines to be achievable through the application of the best
available demonstrated control technology, processes, operating
methods, or other alternatives, including, where practicable, a
standard permitting no discharge of pollutants.
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 achievable including
treatment techniques, process and procedure innovations,
operating methods and other alternatives. The regulations
proposed herein set forth effluent limitations guidelines
pursuant to Section 304 (b) of the Act for the asbestos
manufacturing source category.
Section 306 of the Act requires the Administrator, within one
year after a category of sources is included in a list published
pursuant to Section 306 (b) (1) (A) of the Act, to propose
regulations establishing Federal standards of performances for
new sources within such categories. The Administrator published
in the Federal Register of January 16, 1973 (38 F. R. 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
source category, which was included within the list published
January 16, 1973.
-------
SUMMARY OF METHODS USED FOR DEVELOPMENT OF THE
LIMITATIONS GUIDELINES AND STANDARDS OF PERFORMANCE
EFFLUENT
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 subcategorization 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 analyses of (1) the source and
volume of water used in the process employed and the sources of
waste and waste waters 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-process 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 were also identified. In addition, the non-
water quality environmental impact, such as the effects of the
application of such technologies upon other pollution problems,
including air, solid waste, noise and radiation 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.
-------
Sources of Data
Unlike some industries, the waste waters from the asbestos
manufacturing industry have received almost no attention in the
engineering and pollution control literature. Very few plants
have any information more extensive than the results of analyses
of one or a few grab samples of the final effluent. The data
used in this document were necessarily very limited and were
derived from a number of sources. Some of the sources included
published literature on manufacturing processes, EPA technical
publications on the industry, and consultation with qualified
personnel. Most of the information on waste water volumes and
characteristics, however, was obtained from RAPP applications and
from an on-site sampling program carried out during the
preparation of this document. Some additionnal information was
derived from a questionnaire distributed through the Asbestos
Information Association, North America.
Twelve corporations at 51 locations in the United states
manufacture products which are covered by this document. At
thirteen locations, two or more products are made, resulting in a
total of 68 manufacturing facilities having one or two production
lines each. RAPP applications were available and used for 37 of
these facilities. Except for two locations, these applications
covered all of the plants in the industry that discharge waste
waters to navigable streams. The applications provided data on
the characteristics of intake and effluent waters, water usuage,
waste water treatment provided, daily production, and raw
materials used.
The program of visiting and sampling at ten selected
manufacturing plants was designed to verify the available data on
waste water characteristics, develop flow diagrams, observe water
conservation practices, and define existing treatment techniques
and associated cost. All of the information about untreated and
partially treated waste waters was obtained from the sampling
program.
The number of known manufacturing facilities in each product
subcategory and the means of waste water disposal are presented
in Table 1. Also shown are the number visited and sampled by the
contractor. It should be noted that five of the facilities that
achieve zero discharge by comple recycle are at one location and
are served by a common treatment unit.
A voluntary questionnaire was distributed to its membership by
the Asbestos Information Association, North America. It. outlined
the types of information desired, if available. Since most of
the companies in the industry were contacted directly by the EPA
contractor, the purpose of distributing the questionnaire was to
provide the remaining plants an opportunity to participate in the
study. A copy of the questionnaire is presented on the following
pages.
-------
00
TABLE 1
MANUFACTURING FACILITIES IN THE
ASBESTOS MANUFACTURING INDUSTRY
Asbestos-Cement
Pipe Sheet
Discharge :
to steam
to municipal
system
non-recycle
non-evap'n.
Total
RAPP Application
Visted
Sampled
11
1
1
1
14
11
4
3
7
4
2
0
13
7
3
2
Asbestos
Paper
7
4
1
0
12
5
3
2
Asbestos
Millboard
3
2
2
0
7
3
4
2
Asbestos
Roofing
5
3
1
0
9
5
1
1
Asbestos
Floor Tile
6
7
0
0
13
6
2
1
-------
QUESTIONNAIRE FORM
I GENERAL
A. Company name
B. Address
C. Contact - company personnel
D. Telephone number
E. Contact-plant personnel
F. Address of plant reporting
G. Plant telephone number
II MANUFACTURING PROCESS CHARACTERIZATION (Separate sheet for
each product)
A. Product
B. Manufacturing process
C. Major ingredients and general formulation
D. Production rate
E. Operating Schedule
F. Number of employees
III PROCESS WASTE WATERS
A. Volumes and sources
How and why water is used in the process?
B.
C.
D.
E.
Does the source, volume, or character of waste water vary
depending on the type or quality of product?
How do waste water characteristics change during start-up
and shutdown as compared to normal operation?
Quantity and point of application of acid, pigment, or
other special chemicals used that might enter the waste
water stream.
-------
F. Information, if available, on untreated waste water;
1.
PH
2. Alkalinity
3. Total solids
U. Suspended solids
5. Dissolved solids
6. Temperature
7. BOD5
8. COD
9. Phosphorus
G. Waste water treatment
1. Waste water sources and volumes to treatment facility
2. Reason for treatment
3. Describe treatment system and operation
1. Type and quantity of chemicals used, if any
5. Available information on treated waste water quality
{same items as Section III F, above)
H. Waste water recycle
1. Is any waste water recycled presently?
2. Can waste water be recycled?
10
-------
I In-plant methods of water conservation and/or waste reduction
j. Identify any air pollution, noise or solid wastes resulting
from treatment or other control methods. How is the solid
waste disposed of?
K. Cost information (Related to water pollution control)
1. Treatment plant and/or equipment
2. Operation (Personnel, maintenance,etc.)
3. Power
4. Estimated equipment life
L. Water pollution control methods being considered for future
application
IV Other waste water, e.g., boiler blowdown, spent cooling water,
water treatment residues, etc., same informtion as in Section
III above
V Water requirements
1. Volume and sources
2. Uses (including volume)
a. Process
b. Cooling
c. Washing
d. Dust suppression
e. Plant cleanup
f. Sanitary (if available)
g. Boilers
h. Other
3. Available information on raw water quality
4. Pretreatment provided
a. Volume treated
b. Reason for treatment
c. Describe treatment system and operation
11
-------
d. Type and quantity of chemicals used
e. Available information on treated water quality
12
-------
GENERAL DESCRIPTION OF THE INDUSTRY
Although known as a curiosity since biblical times, asbestos was
not used in,manufacturing until the, latter , ha}J;s 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 asbestos, 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 manufactured products that contain asbestos.
Asbestos is actually a group name that refers to several
serpentine minerals having different chemical compositions but
similar characteristics. 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. The shorter grades are normally used in the
products covered in this document.
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:
Asbestos-cement products
Floor tile
Paper and felts
Friction products
Textiles
Packing and gaskets
Sprayed insulation
Miscellaneous uses
25%
18
14
10
3
3
2
25
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.
This document covers the first three groups in the above list.
These groups were selected because they represent a major segment
of the industry; water is an ingredient in the manufacturing pro-
cess, with two exceptions; and they were regarded as the most im-
portant sources of water pollutants in this industrial category.
13
-------
Asbestos-Cement Products (A/C Pipe and A/C Sheet)
Asbestos fibers in asbestos-cement products serve the same role
as steel rods in reinforced concrete, i.e., they add strength.
Portland cement and silica are also major ingredients of these
products.
Asbestos-cement pipe is manufactured for use in high pressure and
low pressure applications in diameters from 7.6 to 91.5 cm (3 to
36 inches) and in lengths up to 4 meters (13 feet). It is used
to carry waste waters, water supplies, and other fluids and in
venting and duct systems. Asbestos-cement flat and corrugated
sheets are used for exterior sheathing, siding and roofing,
interior partitions, packing in cooling towers, laboratory bench
tops, and many other specialty applications.
Asbestos Floor Tile
The shortest grades of asbestos fibers are used in vinyl and
asphalt floor tile manufacture. The fibers are used to provide
dimensional stability. Today, vinyl asbestos floor tile accounts
for most of the asbestos used in this category, with asphalt tile
serving some special applications and where darker shades are
permissible.
Asbestos Papers and Millboard
Asbestos papers have a high fiber content and are manufactured
with a variety of binders and other additives for many
applications. These include pipe coverings, gaskets, thermal
linings in heaters and ovens, and wicks. Heavier papers are
commonly used for roofing materials and shingles. Millboard is a
heavier, stiffer form of paper that includes clays, cement, or
other additives. It is used for stove lining, filament supports
in toasters, and several other high temperature applications.
MANUFACTURING LOCATIONS
The locations of the plants that manufacture the products covered
in this document are listed in Table 2. This listing includes
all the plants as reported by the major manufacturers. All of
the available known information from the plants at these
locations was collected for use in this study. At several
plants, no informati on about waste-water volumes or
characteristics was known.
At most of the plants, only one asbestos product is manufactured.
There are three reported locations that manufacture more than one
category of asbestos products in the same plant in a manner that
results in a combined waste water flow. Since the waste waters
from all the asbestos products categories, except roofing and
floor tile, have many common characteristics, they are generally
treatable by the same types of control technology, consequently,
14
-------
TABLE 2
LOCATIONS OF ASBESTOS MANUFACTURING PLANTS
State
Arkansas
California
Ui
Florida
Georgia
Illinois
Location
Van Buren
La Mirada
South Gate
Riverside
Santa Clara
Los Angeles
Long Beach
Long Beach
Los Angeles
Pittsburg
Stockton
Green Cove Springs
Savannah
Kankakee
Chicago
Joliet
Company
Cement Asbestos Products Co,
American Biltrite Rubber
Armstrong Cork Company
Certain-Teed Products Corp.
Certain-Teed Products Corp.
The Flintkote Company
G-AF Corporation
Johns-Manville
Johns-Manville
Johns-Manville
Johns-Manville
Johns-Manville
Johns-Manville
Armstrong Cork Company
The Flintkote Company
GAF Corporation
Products
Alabama
Ragland
Mobile
Cement Asbestos Products Co.
GAF Corporation
A-C Pipe
A-C Sheet
A-C Pipe
Floor Tile
Floor Tile
A-C Pipe
A-C Pipe
Floor Tile
Floor Tile
A-C Pipe
Roofing
A-C Sheet,
Paper
A-C Pipe
A-C. Pipe
Roofing
Floor Tile
Floor Tile
Floor Tile
-------
TABLE 2 (contd)
LOCATIONS OF ASBESTOS MANUFACTURING PLANTS
State
Location
Company
Products
Illinois (contd)
Waukegan
Johns-Manville
Louisiana
Mas s achus etts
Mississippi
Missouri
New Hampshire
New Jersey
New Orleans
Marrero
New Orleans
Milis
Billerica
Jackson
St. Louis
St. Louis
Nashua
Tilton
Linden
South Bound Brook
The Flintfcote Company
Johns -Manville
National Gypsum Company
GAF Corporation
Johns-Manville
Armstrong Cork Company
Certain-Teed Products Corp.
GAF Corporation
Johns -Manville
John s -Manville
Celotex Corporation
GAF Corporation
A-C Pipe,
A-C Sheet,
Paper,
Millboard,
Roofing
Floor Tile
A-C Sheet,
Roofing
A-C Sheet
Roofing
Millboard
Floor Tile
A-C Pipe
A-C Sheet
A-C Sheet
Paper,
Millboard
Paper
A-C Sheet,
Roofing
-------
TABUS 2 icontd)
LOCATIONS OF ASBESTOS MANUFACTURING PLANTS
State
Hew Jersey { contd)
New York
Ohio
Pennsylvania
Location
Manville
Millington
Fulton
Vails Gate
Brooklyn
Cincinnati
Ravenna
Hamilton
Lancaster
Ambler
Erie
Erie
Vhitehall
Arabler
Norristown
Company
Johns -Manville
National Gypsum Company
Armstrong Cork Company
GAF Corporation
Kentile Floors, Inc.
Celotex Corporation
The Flintkote Company
Nicolet Industries, Inc.
Armstrong Cork Company
Certain-Teed Products Corp.
GAF Corporation
GAF Corporation
GAF Corporation
Nicolet Industries, Inc.
Nicolet Industries, Inc.
Products
A-C Pipe,
A-C Sheet,
Paper ,
Roofing
A-C Sheet
Paper
Floor Tile
Floor Tile
A-C Sheet,
Paper ,
Millboard
A-C Pipe
Paper
Floor Tile
A-C Pipe
Paper ,
Millboard
Roofing
Paper
A-C Sheet,
Millboard
Paper ,
Millboard
-------
Puerto Rico
TABLE 2 (contd)
LOCATIONS OF. ASBESTOS MANUFACTURING PLANTS
State
Texas
Location
Hillsboro
Houston
Denison
Fort Worth
Company
Certain-Teed Products Corp.
GAP Corporation
Johns -MamriHe
Johns-Manville
Products
A-C Pipe
Floor Tile
A-C Pipe
Paper ,
Roofing
Ponce
Boringuen Asbestos Cement Corp,
A-C Sheet
OO
-------
the combined waste waters from the manufacture of multiple
asbestos products do not present significant additional problems
in control.
Of more significance from a water pollution control point of view
is the manufacture of non-asbestos products with confluent waste
streams at some of the locations. The most common combinations
are the manufacture of plastic pipe at asbestos-cement pipe
plants and the manufacture of "organic" (cellulose fiber) paper
at asbestos paper plants. Plastic pipe manufacture is not likely
to result in the discharge of significant pollution other than
waste heat. Organic paper manufacturing waste waters, however,
are significantly stronger and of different character than those
from asbestos paper production. The raw materials are often
paperstock (salvaged paper) as well as virgin pulp and the wastes
are highly colored, turbid, and high in oxygen demand.
MANUFACTURING PROCESSES
With the exception of roofing and floor tile manufacture, there
is a basic similarity in the methods of producing the various
asbestos products. The asbestos fibers and other raw materials
are first slurried with water and then formed into single or
multi-layered sheets as most of the water is removed. The
manufacturing process always incorporates the use of save-alls
(settling tanks of various shapes) through which process waste
waters are usually routed. Water and solids are recovered and
reused from the save-all, and excess overflow and underflow
constitute the process waste streams. In all of these product
categories, water serves both as an ingredient and a means of
conveying the raw materials tc and through the forming steps.
ASBESTOS-CEMENT PRODUCTS (A/C Pipe and A/C Sheet)
The largest single use category of asbestos fibers in the United
States is the manufacture of asbestos-cement products. The pipe
segment is the largest component of this product category.
Raw Materials
Asbestos-cement products contain from 10 to 70 percent asbestos
by weight, usually of the chrysotile variety. Crocidolite and
other types are used to a limited extent depending upon the
properties required in the product. Portland cement content
varies from 25 to 70 percent. Consistent cement quality is very
important since variations in the chemical content or fineness of
the grind can affect production techniques and final product
strength. The remaining raw material, from 5 to 35 percent, is
finely ground silica. Some asbestos-cement pipe plants have
facilities for grinding silica as an integral part of their
operations. Finely ground solids from damaged pipe or sheet
trimmings are used by some plants as filler material. A maximum
19
-------
of 6 percent filler can be used in some products before strength
is affected.
The interwoven structure formed by the asbestos fibers in
asbestos-cement products functions as a reinforcing medium by
imparting increased tensile strength to the cement. As a result,
there is a 70 to 80 percent decrease in the weight of the product
required to attain a given structural strength. It is important
that the asbestos be embedded in the product in a completely
fiberized or willowed form, and the necessary fiber conditioning
is frequently carried out prior to mixing the fiber with the
cement and silica. In some cases, however, this fiber opening is
accomplished while the wet mixture is agitated by a pulp beater,
or hollander.
Manufacture
Asbestos-cement sheet products are manufactured by the dry
process, the wet process, or the wet mechanical process. Figures
1 through 3 illustrate the sequence of steps in each of these
manufacturing processes with the sources of wastes indicated.
Products having irregular shapes are formed by molding processes
which account for only a very limited production today.
Extrusion processes are not widely used in the United states.
Dry Procegs-
In the dry process (Figure 1), which is suited to the manufacture
of shingles and other sheet products, a uniform thickness of the
mixture of dry materials is distributed onto a conveyor belt,
sprayed with water, and then compressed against rolls to the
desired thickness and density. Rotary cutters divide the moving
sheet into shingles or sheets which are subsequently removed from
the conveyor for curing. The major source of process waste water
in this process is the water used to spray clean the empty belt
as it returns.
Wet Process-
The wet process (Figure 2) produces dense sheets, flat or corru-
gated, by introducing a slurry into a mold chamber and then com-
pressing the mixture to force out the excess water. A setting
and hardening period of 24 to 48 hours precedes the curing
operation. The large, thick monolithic sheets used for
laboratory bench tops are manufactured by this process. The
grinding operations used to finish the sheet surfaces produce a
large quantity of dust which may be discharged with the process
waste waters. This affords a means of reducing and controlling
air emissions.
Wet Mechanical Process-
The wet mechanical process, which is also used for the
manufacture of asbestos-cement pipe (Figure 4), is similar in
20
-------
WATER
STEAM
RAW MATERIALS
STORAGE
PROPORTIONING
DRY MIX
ROLLING
CUTTING
CURING
FINISHING
STORAGE
CONSUMER
WASTEWATER
SOLIDS
CONDENSATE
Figure 1 - Asbestos-Cement Sheet Manufacturing Operations,
Dry Process
21
-------
RAW MATERIALS
STORAGE
PROPORTIONING
DRY MIX
WATER
WET MIX
HARDENING
STEAM
CURING
FINISHING
STORAGE
WASTE WATER
CONDENSATE
SOLIDS
CONSUMER
Figure 2 - Asbestos-Cement Sheet Manufacturing Operations,
Wet Process
22
-------
WATER
STEAM
RAW MATERIALS
STORAGE
PROPORTIONING
DRY MIX
WET MIX
FORMING
CURING
AIR/AUTOCLAVE
RECYCLED SOLIDS
RECYCLED WATER
~1
WASTEWATER
CLARIFICATION
(SAVE-ALL)
SLUDGE
CUTTING
CONDENSATE
SOLIDS
FINISHING
STORAGE
CONSUMER
Figure 3 - Aab«stc3-C«ment Sheet Manufacturing Operations,
Vet Me«hanical Process
23
-------
principle to some papermaking processes. The willowed asbestos
fiber is conveyed to a dry mixer where it is blended with the
cement, silica, and filler solids. After thorough blending of
the raw materials, the mixture is transferred to a wet mixer or
beater. Underflow solids and water from the save-all are added
to form a slurry containing about 97 percent water. After
thorough mixing, the slurry is pumped to the cylinder vats for
deposition onto one or more horizontal screen cylinders. The
circumferential surface of each cylinder is a fine wire mesh
screen that allows water to be removed from the underside of the
slurry layer picked up by the cylinder. The resulting layer of
asbestos-cement material is usually from 0.02 to 0.10 inch in
thickness. The layer from each cylinder is transferred to an
endless felt conveyor to build up a single mat for further
processing. A vacuum box removes additional water from the mat
prior to its transfer to mandrel or accumulator roll. This winds
the mat into sheet or pipe stock of the desired thickness.
Pressure rollers bond the mat to the stock already deposited on
the mandrel or roll and remove excess water. Pipe sections are
removed from the mandrel, air cured, steam cured in an autoclave,
and then machined on each end.
In the manufacture of sheet products by the wet mechanical
process, the layer of asbestos-cement on the accumulator roll is
periodically cut across the roll and peeled away to form a sheet.
The sheet is either passed through a pair of press rollers to
shape the surface and cut the sheet into shingles, formed into
corrugated sheet, or placed onto a flat surface for curing.
The asbestos-containing
recycled to the process.
manufacturing process.
water removed from the slurry or mat is
Very little asbestos is lost from the
The cylinder screen and felt conveyor must be kept clean to
insure proper operation. Cylinder showers spray water on the
wire surface after the mat has been removed by the felt. Any
cement or fiber particles are washed out of the holes in the
screen to prevent "blinding."
The cylinders, mandrels, and accumulator rolls are occasionally
washed in acetic or hydrochloric acid to remove cement deposits.
This cleaning may be carried out while the machine is in
operation or the component, especially cylinder screens, may be
removed to a separate acid washing facility.
The felt washing showers are a row of high-pressure nozzles that,
with the aid of a "whipper," wash fiber out of the felt after the
mat of fiber has been picked up by the mandrel or accumulator
roll. Fiber build-up in the felt can prevent vacuum boxes from
removing excess water from the mat.
24
-------
RAW MATERIALS
STORAGE
PROPORTIONING
DRY MIX
WATER
STEAM
WATER
4£
RECYCLED SOLIDS
RECYCLED WATER
WET MIX
"I
WASTEWATER
CLARIFICATION
(SAVE-ALL)
FORMING
"
CURING
(AUTOCLAVE)
PIPE END
FINISHING
RECYCLED
HYDROSTATIC
TESTING
FINISHING
STORAGE
SLUDGE
CONDENSATE
SOLIDS
WASTEWATER
CONSUMER
Figure 4 - Asbestos-Cement Pipe Manufacturing Operations,
Wet Mechanical Process
25
-------
In-Plant_RecYCling
Asbestos-cement product plants recycle the majority of their
water as a means of recovering all usable solids. All water
serving as the carrying agent, 80 to 90 percent of the water in
the process, passes through a save-all after leaving the machine
vat. Solids that settle out and concentrate near the bottom of
the save-all are pumped to the wet mixer to become part of a new
slurry. Much of the clarified overflow from the save-all ca.n be
used for showers, dilution, and various other uses depending upon
the efficiency of the save-all.
The save-all overflow may be discharged from the plant or may be
treated and returned to the plant for whatever uses its quality
justifies. This may include water for wet saws, vacuum pump
seals, cooling, hydrotesting, or makeup water for plant startup.
If any of these uses cannot be served by treated water, fresh
water must be used since the quality and temperature of save-all
overflow water is rarely acceptable without additional
clarification.
At most asbestos-cement product plants, part of the products that
are damaged or unacceptable for other reason are crushed, ground,
and used as filler in new products. The remainder is crushed and
added to a refuse pile or landfill.
Asbestos-cement sheet plants trim the edges of the wet sheets as
they come off the accumulator roll. The trimmings are
immediately returned to the wet mixer. At this stage, the cement
has not begun to react and the trimmings can be an active part of
the new slurry.
Operating Schedule
Asbestos-cement pipe plants typically operate 24 hours a day and
five or six days a week. Sheet plants may operate two shifts a
day rather than three depending upon market demand.
ASBESTOS PAPER
Asbestos paper has a great variety of uses and ingredient
formulas vary widely depending upon the intended use of the
paper. The purchaser frequently specifies the exact formula to
insure that the paper has the desired qualities.
Raw Materials
Asbestos paper usually contains from 70 to 90 percent asbestos
fiber by weight, usually the short grades. A mixture of the
various varieties of asbestos fiber is used with chrysotile as
the principal type. The binder content of asbestos paper
accounts for 3 to 15 percent of its weight. The content and type
26
-------
varies with the desired properties and intended applications of
the paper. Typical binders are starch, glue, cement, gypsum, and
several natural and synthetic elastomers.
Asbestos paper used for roofing paper, pipe wrapping, and
insulation usually contains between 5 and 10 percent kraft fiber.
Mineral wool, fiberglass, and a wide variety of other
constituents are included to provide special properties and may
represent as much as 15 percent of the weight.
Manufacture
Asbestos paper is manufactured on machines of the Fourdrinier and
cylinder types that are similar to those which produce cellulose
(organic) paper. The cylinder machine is more widely employed in
the industry today. The overall manufacturing process is shown
in Figure 5 with waste sources indicated.
The mixing operation combines the asbestos fibers with the
binders and any other minor ingredients. A pulp beater or
hollander mixes the fibers and binder with water into a stock
which typically contains about three percent fiber. Upon leaving
the stock chest, the stock is diluted to as little as one-half
percent fiber in the discharge chest. The amount of dilution
depends upon the quality of the paper to be produced.
The discharge chest of a Fourdrinier paper machine deposits a
thin and uniform layer of stock onto an endless moving wire
screen through which a major portion of the water is drawn by
suction boxes or rolls adjacent to the sheet of paper. The sheet
is then transferred onto an endless moving felt and pressed
between pairs of rolls to bring the paper to approximately 60
percent dryness. Subsequently, the continuous sheet of paper
passes over heated rolls, while supported on a second felt, to
effect further drying. This is followed by
produce a smooth surface, and winding of
spindle.
calendering, to
the paper onto a
The operation of a cylinder paper-making machine includes a
mixing operation for stock as indicated for the Fourdrinier
machine. Cylinder-type paper machines usually have four to eight
cylinders instead of two as in most asbestos-cement pipe
machines.
The stock is pumped to the cylinder vats of the machine. Each
vat contains a large screen-surfaced cylinder extending the full
length of the vat. The stock slurry flows through the screen
depositing a thin layer of fiber on the surface of the rotating
cylinder before flowing out through the ends of the cylinder.
The layer of fiber is then transferred to a carrier felt moving
across the top of the rotating cylinders. The layers picked up
from the cylinders are pressed together becoming a single
homogeneous sheet as the felt passes over each successive
cylinder.
27
-------
WATER
WATER
STEAM
RAW MATERIALS
STORAGE
PROPORTIONING
COOLING
WATER
r
MIXING
STOCK CHEST
METERING
PAPER
MACHINE
DRYING
__ RECYCLED SOLIDS
RECYCLED WATER _
CLARIFICATION
(SAVE-ALL)
COOLING WATER
CONDENSATE
WASTEWATER
L.J
SLUDGE
STORAGE
CONSUMER
OR
ROOFING PLANT
Figure 5 - AsUe*to» Paper-Manufaeturing Operationa
28
-------
Vacuum boxes draw water out and pressure rolls squeeze water out
of the sheet and felt until the sheet is dry enough to be removed
from the felt. After leaving the felt, the sheet is dried on
steam rolls and in ovens. The paper is then calendered to
produce a smooth surface and wound onto a spindle.
The width of the paper sheet is regulated by the deckles, a row
of nozzles located at each end of the cylinder screens. The
deckles spray water on the screen at the edge of the sheet and
wash off excess fiber.
The cylinder showers are a row of nozzles that spray water on the
surface of the cylinder screens after the paper stock mat has
been removed by the felt. They wash any remaining fiber and
binder out of the holes in the screens to prevent a build-up of
fiber from "blinding" the screen and stopping the flow of water
required to deposit a layer of fiber on the surface of the
cylinder.
The felt washing operations are carried out using high pressure
nozzles as in asbestos-cement pipe manufacture.
The asbestos-containing water, or "white water," which is removed
from the stock prior to passage across the heated drying rolls is
recycled to the process..
Water Usage
Water serves three basic purposes in the asbestos paper
manufacturing process: ingredient carrier, binder wetting agent,
and heat transfer fluid, other uses include water for showers,
deckles, pump seals, plant make-up, boiler make-up, and cooling.
Fresh water enters the system as boiler make-up, process make-up,
pump seal water, and shower water. Boiler make-up water provides
steam for heating the paper stock and drying the finished paper.
The steam used to heat the stock slurry becomes a part of the
slurry and must be replaced. Condensate from the drying rolls is
recovered and returned to the boiler. Fresh water must be used
to cool the dried paper unless a cooling tower is available.
Save-all overflow and other plant water is usually too hot for
such purposes. Large quantities of fresh water are required
during plant start-up to .fill the system. This occurs
infrequently, however. Small quantities of water are required
continuously to replace that which evaporates during drying and
that which becomes a permanent part of the paper. The
characteristics of some paper products are such that fresh water
must be used for part, or all, of the beater make-up water.
Cylinder and felt washing showers usually require fresh water be-
cause save-all overflow water is rarely clean enough to be used
in the high pressure shower nozzles without causing plugging.
29
-------
Fresh water is used for the pump shaft seal water because the
presence of dirt in the seal water will cause plugging and can
cause scoring of the shaft. Although the cooling water and part
of the pump seal water may be discharged from the plant after a
single use, most of the fresh water introduced into the plant
enters the ingredient carrying system, and, therefore, the paper
machine save-all loop.
The majority of the water in a paper plant serves as an
ingredient carrier and continually circulates in a loop through
the paper machine and the save-all. All water flowing out of the
cylinder screen and that drawn by vacuum out of the wet paper
sheet is pumped to the save-all. The solids settle to the bottom
of the save-all and are pumped to the stock chest of the beater.
Occasionally, the solids from the save-all must be discharged
from the plant due to a product change, rapid setup of the
binder, or a plant shutdown. Save-all overflow water is used for
beater makeup, dilution, deckle water, and occasionally shower
water.
Excess overflow water must be discharged from the plant or sent
to a waste water treatment facility for additional treatment
before it can be reused.
Trimmings from the edge of the paper, defective paper, and other
waste paper can usually be returned to the beater and repulped
for recycling.
Asbestos paper manufacturing plants typically operate 24 hours
day and 7 days a week.
MILLBOARD
Asbestos millboard is considered by some to be a very heavy paper
and is in fact very much like thick cardboard in texture and
structural qualities. It can easily be cut or drilled and can be
nailed or screwed to a supporting structure.
Baw Materials
Millboard formulas vary widely depending upon the intended use of
the product. Purchasers frequently specify the ingredients and
composition of the millboard to insure that the product meets
their particular requirements. Asbestos content ranges between
60 and 95 percent with the higher content for products that will
be in close or direct contact with high temperature materials.
Portland cement and starch are the most common binders used and
represent 5 to 40 percent of the product. Clay, lime, mineral
wool, and several other materials are frequently used as fill
30
-------
material or to provide special qualities.
important ingredient in millboard.
Manufacture
Water is also an
The manufacturing steps in asbestos millboard production with
waste sources indicated are shown in Figure 6. Millboard is
produced on small cylinder-type machines similar to those used
for making asbestos-cement pipe. The machines are equipped with
one or two cylinder screens, conveying felt, pressure rolls, and
a cylinder mold. After the ingredients are mixed in a beater,
the slurry is transferred to a stirring vat or stock chest from
which it is diluted and pumped to the cylinder vats of the
millboard machines. Each cylinder vat contains a large screen
surfaced cylinder extending the full length of the vat. The
slurry flows through the screen depositing a mat of fiber on the
surface of the rotating cylinder before flowing out through the
ends of the cylinder. The mat of fiber is then transferred to a
carrier felt moving across the top of the rotating cylinder. On
two-cylinder machines, the mats from the first and second
cylinders are pressed together becoming a single homogeneous
sheet as the felt picks up the mat of fiber from the second
cylinder. Pressure rolls above the felt squeeze water from the
mat as it is picked up from the cylinders. Some millboard
machines have vacuum boxes adjacent to the felt that draw water
out of the mat of fibers. Additional pressure rolls remove more
water from the mat as it is wound onto the cylinder mold.
The cylinder mold is a drum about four feet wide and usually
about four feet in diameter. As the carrier felt passes the
cylinder mold, the mat is transferred to the cylinder because the
adhesion to the wet cylinder surface is greater than the adhesion
to the felt. The cylinder mold rotates, collecting successive
layers of fiber until the desired thickness is obtained. The
cylinder is then momentarily stopped and the mat of fiber cut
along a notch on the surface of the cylinder parallel to the
cylinder axis. The sheet of millboard is removed as the cylinder
starts rotating to build up another sheet. The wet millboard,
containing about 50 percent water, is air dried or moved into an
autoclave or oven for rapid curing. Finished millboard usually
contains 5 to 6 percent water.
The operation of the deckles, cylinder showers, and felt washing
showers is basically the same as described previously for
asbestos paper.
Water_U^age
The uses and flow patterns of water .in millboard manufacturing
operations are very similar to those in asbestos paper making.
In-Plant Recycling
31
-------
RAW MATERIALS
STORAGE
PROPORTIONING
WATER
r
_ RECYCLED SOLIDS
RECYCLED WATER
MIXING
FORMING
DRYING
TRIMMING
FINISHING
STORAGE
CLARIFICATION
(SAVE-ALL)
SOLIDS
WASTEWATER
SLUDGE
C0NWMER
6 - A*b**tM. Uillbeard Manufacturing Operation*
32
-------
As with the asbestos products covered previously, most of the
water in the millboard manufacturing process serves as an
ingredient carrier and continually circulates in a loop through
the millboard machine and the save-all. All water flowing out of
the cylinder screen and that drawn by vacuum out of the wet
millboard is pumped to the save-all. Solids that settle in the
save-all are pumped to the stock chest or the beater. Save-all
overflow water is used for beater make-up, dilution, deckle
water, and occasionally shower water. Excess overflow water must
be discharged from the plant or sent to a treatment facility for
additional treatment before it can be reused.
When possible, trimmings from millboard sheets are returned to
the beater and repulped for use in new millboard. Most
millboards can accept from 5 to 10 percent reclaimed material.
Operating Schedule
A typical asbestos millboard plant operates two or
per day and five or six days a week.
three shifts
ASBESTOS ROOFING
Asbestos roofing is made by saturating heavy grades of asbestos
paper with asphalt or coal tar with the subsequent application of
various surface treatments. The stock paper may be single or
multiple layered and usually contains mineral wool, kraft fibers,
and starch as well as asbestos. Fiberglass filaments or strands
of wire may be embedded between layers for reinforcement.
Manufacture
Figure 7 shows the major steps in the manufacture of asbestos
roofing. Asbestos paper is pulled through a bath of hot coal tar
or asphalt. After it is thoroughly saturated, the paper passes
over a series of hot rollers to set the coal tar or asphalt in
the paper. The paper then passes over cooling rollers that
reduce the temperature of the paper and give it a smooth surface
finish. At some plants, cooling water is sprayed directly on the
surface of the saturated paper.
Roll roofing is coated with various materials to prevent adhesion
between layers and then passed over a final series of cooling
rollers. The roofing is then air dried and rolled up and
packaged for marketing. The manufacture of asbestos roof
shingles is similar from a waste water point o£ view.
Water_Usage
Water is used in two ways in the production of roofing. It is
converted to steam to heat the saturating baths and hot rollers
and for cooling the hot paper after it has been saturated.
Condensate from the saturating bath coils and the hot rollers is
33
-------
ASBESTOS PAPER
STORAGE
HOT COAL TAR
OR ASPHALT^r
SATURATION
STEAM
COOLING
WATER
FUMES
HEAT TREATMENT
UNCOATED
ROOFING
COOLING
WATER
COATING
COOLING
CUTTING
ROLLING
PACKAGING
STORAGE
COOLING
WATER
COOLING
WATER
WASTEWATER
CONSUMER
Flfor* 7 - A«b«rt+i R»efIng )tatt£*etuiing Qpwrati
-------
collected and returned to the boilers. Fresh make-up water in
small quantities is required to replace boiler blowdown water,
steam, and condensate that escapes through leaks. Cooling water
is used once and discharged unless cooling towers or other means
of cooling the water are available. The only process waste water
associated with roofing manufacture is that originating in the
spray cooling step. In many cases, this contaminated contact
cooling water is discharged with the clean non-contact cooling
water.
Operating schedule
A typical roll roofing plant operates one or two shifts a day on
a five-day per week schedule.
FLOOR TILE
Most floor tile manufactured today uses a vinyl resin, although
some asphalt tile is still being produced. The manufacturing
processes are very similar and the water pollution control
aspects are almost identical for the two forms of tile.
Raw Materials
Ingredient formulas vary with the manufacturer and the type of
tile being produced. The asbestos content ranges from 8 to 30
percent by weight and usually comprises very short fibers.
Asbestos is included for its structural properties and it serves
to maintain the dimensional stability of the tile. PVC resin
serves as the binder and makes up 15 to 25 percent of the tile.
Chemical stabilizers usually represent about 1 percent.
Limestone and other fillers represent 55 to 70 percent of the
weight. Pigment content usually averages about 5 percent, but
may vary widely depending upon the materials required to produce
the desired color.
Manufacture
The tile manufacturing process, shown in Figure 8, involves
several steps; ingredient weighing, mixing, heating, decoration,
calendering, cooling, waxing, stamping, inspecting, and
packaging. The ingredients are weighed and mixed dry. Liquid
constituents, if required, are then added and thoroughly blended
into the batch. After mixing, the batch is heated to about 150
degrees C and fed into a . mill where it is joined with the
remainder of a previous batch for continuous processing through
the rest of the manufacturing operation.
The mill consists of a series of hot rollers that squeeze the
mass of raw tile material down to the desired thickness. During
the milling operation, surface decoration in the form of small
colored chips of tile (mottle) are sprinkled onto the surface of
the raw tile sheet and pressed in to become a part of the sheet.
35
-------
RAW MATERIALS
STORAGE
PROPORTIONING
STEAM
COOLING
WATER
Q.
Q
Ul
o
UJ
oc
MIXING
CONDENSATE
FORMING
ROLLING
COOLING
COOLING
WATER
WASTEWATER
FINISHING
CUTTING
PACKAGING
STORAGE
CONSUMER
Figure 8 - AaberUs Jl»er Tile llumf*eturiiig Op«ratlona
36
-------
Some tile has a surface decoration embossed and inked into the
tile surface during the rolling operation. This may be done
before or after cooling. After milling, the tile passes through
calenders until it reaches the required thickness and is ready
for cooling. Tile cooling is accomplished in many ways and a
given tile plant may use one or several methods. Water contact
cooling in which the tile passes through a water bath or is
sprayed with water is used by some plants. Others use non-
contact cooling in which the rollers are filled with water. In
some plants, the sheet of tile passes through a refrigeration
unit where cold air is blown onto the tile surface. After cool-
ing, the file is waxed, stamped into squares, inspected, and
packaged. Trimmings and rejected tile squares are chopped up and
reused.
Water Usage
Water serves only as a heat transfer fluid. It is used in the
form of steam to heat the batches and the hot rollers. Fresh
water is required for boiler make-up, but only in quantities
large enough to replace leakage and boiler blowdown water. Non-
contact cooling water remains clean and can be reused continually
if cooling towers or water chillers are available to remove the
heat picked up from the hot tile.
Make-up water is required only to replace water that leaks from
the system. Direct contact cooling water from the cooling baths
or sprays does not become contaminated from direct contact with
the tile but may pick up dust or other materials. This water may
be reused if facilities are available to clean the water and
remove the heat. Fresh water is required to replace leakage and
water that evaporates. Leakage from all sources collects dirt,
oil, grease, wax, ink, glue, and other contaminants. This
represents a serious potential for pollution if discharged to a
receiving water.
Floor tile plants typically operate 24 hours a day on a five or
six day per week schedule.
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 mining, processing,
transportation, and manufacturing operations. This concern has
recently been expanded to include the general public. Asbestos
is among the first materials to be declared a hazardous air
pollutant under the Clean Air Act amendments of 1970. Stringent
regulations have also been promulgated to control exposure to
workers in the industry.
37
-------
The increased concern with the health effects of asbestos fibers
in the air has produced changes that affect, to some degree, the
water pollution control aspects of the industry. The principal
change has been conversion of dry processes into wet processes
and the use of water sprays to allay dust from mining operations
and slag piles. This shifting is expected to continue in the
future.
While there has been considerable interest and much research on
the health effects of asbestps in air, there has been little
study of the effects of fibers in water. The first major
investigations of this possible problem are now being initiated,
The impetus for these studies was supplied by the finding of
asbestos-like material in the drinking water of Duluth,
Minnesota.
The asbestos manufacturing industry grew rapidly in the first
two-thirds of the 20th century. Many observers expect that
growth will be less rapid in the future. Environmental and
health considerations, plus competition from fiberglass, siliccne
products, aluminum sheet, and other materials, are among the
factors contributing to the slowdown in growth. Many of the
plants visited in this study were not operating at full capacity.
New uses and markets for asbestos may be more difficult to
develop in the future. Despite the decline in the rate of
growth, asbestos has unique characteristics, and its use in
manufacturing can be expected to continue to a significant degree
in the foreseeable future.
38
-------
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 in the asbestos
manufacturing industry were:
1. Product,
2. Raw Materials,
3. Manufacturing Process,
4. Treatability of Waste Waters,
5. Plant Size,
6. Plant Age, and
7. 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 the asbestos
manufacturing industry should be divided into seven
subcategories:
1. Asbestos-cement pipe,
2. Asbestos-cement sheet,
3. Asbestos-cement (starch binder),
4. Asbestos paper (elastomeric binder),
5. Asbestos millboard,
6. Asbestos roofing products, and
7. Asbestos roofing products.
FACTORS CONSIDERED
All of the factors listed above are briefly discussed below, even
though most of them did not serve as bases for categorization.
Product
Despite some basic similarities in the manufacturing processes
used to make the products in the first three categories above,
the final products are distinct and are well defined and
recognized within the industry. In most cases, only one asbestos
product i s made in a given plant. Thi s basi s for
subcategorization is further supported by other factors mentioned
below, but mainly by differences in raw waste loads and volumes.
39
-------
Raw Materials
Many of the raw materials used in asbestos products are natural
materials such as clay, portland cement, and starch. It is sus-
pected that variations in these raw materials result in
operational differences that influence the waste water volume and
strength. There is no quantitative information in the industry
about these influences. Moreover, changes within a product
subcategory at a given plant may occur regularly and the amounts
and types of raw materials may also be changed. These
uncertainties did not permit subcategorization based on raw
materials.
Manufacturing Process
Except for roofing and floor tile, the basic manufacturing
processes are similar for the other asbestos products covered in
this report. within a given product subcategory, the basic
manufacturing processes are very similar. Any differences that
do exist do not greatly influence the quantity or quality of the
effluent. However, differences in the number and size of
auxiliary manufacturing units, such as save-alls, can greatly
affect the waste water effluent, both in
Th erefore, the manuf acturing proce sses
basis for subcategorization.
of Waste water
volume and strength*
could not be used as a
while seemingly similar when described by the common collective
parameters (suspended solids, oxygen demand, etc.), the waste
waters from the different product categories exhibit some
important differences. The differences relate both to the in-
plant and end-of-pipe control measures and to the speed with
which the category can be brought to the point where pollutants
are not discharged. In general the raw waste load and volumes
differed for each product subcategory. No great differences
existed between the asbestos-cement pipe and asbestos-cement
sheet subcategor ies , nor between the two asbe stos paper
subcategories . However, the evidence described in this report
shows that asbestos-cement sheet plants will be able to achieve
zero discharge sometime before asbestos-cement pipe plants. The
same is true for asbestos paper (starch binder) versus asbestos
paper (elastomeric binder) .
Treatability of waste water is, therefore, the major factor
supporting subcategorization based on products.
Plant size was not found to be a factor in categorizing the
asbestos manufacturing industry. All of the plants visited had
either one or two "machines.1* The machines are roughly of about
the same capacity; and, consequently, all of the plants in a
given category, or subcategory, do not range widely in size. The
-------
operational efficiency, quality of housekeeping, lator
availability, and waste water characteristics of the plants do
not differ because of size differences. The largest plants in
the industry are actually multi-product plants and are, in
reality, assemblages of individual product category manufacturing
units.
Plant size does not affect the type or performance of effluent
control measures. As described in Section VII, the basic waste
treatment operation for this industry is sedimentation. Design
is based on hydraulic flow rate and plants with smaller
discharges can use smaller and somewhat less costly treatment
units.
There are a few specialty plants with reported production levels
that are very low. From the data provided, however, no
significant differences in effluent characteristics of these
plants could be detected. Not including these small plants, the
approximate reported daily production ranges for the product
categories are as follows:
Asbestos-cement pipe
Asbestos-cement sheet
Asbestos paper
Asbestos millboard
Asbestos roofing
Asbestos floor tile
135 to 329 kkg (150 to 350 tons)
90 to 230 kkg (100 to 250 tons)
45 to 90 kkg ( 50 to 100 tons)
6 to 14 kkg ( 7 to 15 tons)
(9360 to 450kkg)* (400 to 500 tons)*
300,000 to 650,00 pieces
*The limited data from roofing plants do not permit an accurate
estimate of the full range of production.
Plant_Age
The ages of the plants in the asbestos manufacturing industry
range from a few to 50 or more years. The manufacturing
equipment is often younger than the building housing the plant,
although in some cases used machines have been installed in new
plants. Plant age 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.
Geographic Location
Asbestos manufacturing plants are primarily in the east and south
and in California. There are reportedly no differences in the
processes used throughout the country. Plants in some
southwestern locations are able to reduce the volume of discharge
because of high evaporation losses from lagoons. There are
insufficient data upon which to base standards for these plants.
This form of treatment is not available throughout most of the
nation.
41
-------
-------
SECTION V
WATER USE AND WASTE CHARACTERIZATION
INTRODUCTION
Water is commonly used in asbestos manufacturing as an
ingredient, a carrying medium, for cooling, and for various
auxiliary purposes such as in pump seals, wet saws, pressure
testing of pipe, and others. These uses are described in detail
in following parts of this section. Water is used only for
cooling in the manufacture of asbestos roofing and floor tile
products. In the discussion below, these two categories are not
included unless specifically mentioned. In most asbestos
manufacturing plants the waste waters from all sources are
combined and discharged in a single sewer.
As described in detail in Section IV, asbestos manufacturing, in
almost all cases, involves forming the product from a dilute
water slurry of the mixed raw ingredients. The product is
brought to the desired size, thickness, or shape by accumulating
the solid materials and removing most of the carriage water. The
water is removed at several places in the machine and it,
together with any excess slurry, is piped to the save-all system.
The mixing operations are carried out on a batch, or semi-
continuous basis. Water and materials are returned from the
save-alls as needed during mixing. Excess water and, in some
cases, materials are discharged from the save^all system. Fresh
water and additional raw materials are added during mixing. The
fresh water is often used first as vacuum pump seal water before
going into the mixing operations.
The major source of process waste water in asbestos manufacturing
is the "machine" that converts the slurry into the formed wet
product. It is not practical to; isolate individual sources of
waste water within the machine system. The water is commonly
transported from the machine to the save-all system and back to
the machine in a closed system. To measure the quantity of water
flowing in the machine-save-all recycle system involves a rather
elaborate monitoring program that was beyond the scope of this
study. Only one manufacturing plant provided data on in-plant
water flows that were more than rough estimates. This
information is presented below under asbestos-cement pipe (Figure
9) . The relative amount of internaj. recycling in all asbestos
manufacturing plants is significant and of roughly the same
relative proportion as detailed for this pipe plant.
An important factor influencing both the volume and strength of
the raw waste waters is the save-all capacity in the plant.
Save-alls are basically settling tanks in which solid-liquid
separation is accomplished by gravity. Their purpose is first to
43
-------
FRESH OR
TREATED
WATER
24 L/SEC
(380 GPM)
39 °/o
MAKE-UP, SAWS
HYDROTESTING
COOLING , ETC
TO TREATMENT
OR DISCHARGED
FROM PLANT
14 L/SEC
(225 GPM)
23°/o
PIPE
MACHINE
10 L/SEC
(155 GPM)
16%
52 L/SEC
(820 GPM)
83.5%
SAVE-ALL
REMAINS
IN PIPE
0.3 L/SEC
(5GPM)
.5%
38 L/SEC
(600 GPM)
61 °/o
14 L/SEC
(220 GPM)
22.5 %
24 L/SEC
(375 GPM)
38.5%
Figure 9~- Water Balance Diagram for a Typical
Asbestos-Cement Pipe Plant
-------
recover raw materials (solids) and, second, water. The
efficiency of separation is primarily dependent upon the
hydraulic loading on the save all. Plants with greater save-
capacity have greater flexibility in operation, more water
storage volume, and a cleaner raw waste water leaving the
manufacturing process. In many asbestos manufacturing plants,
the solids in the save-alls are dumped when the product is to be
changed or when it is necessary to remove the accumulated waste
solids at the bottom. It may also be necessary to dump the save-
alls when the manufacturing process is shut down.
ASBESTOS^CEMENT PIPE
Water Usage
The water balance at one asbestos-cement pipe plant was provided
by the plant personnel. The values were verified in this study
as far as possible. The balance is outlined diagrammatically in
Figure 9. The fresh water going into the pipe manufacturing
machine is only about one-quarter of the total used. The rest is
water recycled from the save-all. The percentage figures in
Figure 9 are in terms of the total water entering the
manufacturing system, i.e., the fresh water and that returned
from the save-all.
Fresh water is used for wet saws, hydrotesting, cooling, sealing
vacuum pumps, and making steam for the autoclave as well as make-
up in the mixing unit. Water is used with the saws to control
dust and fiber emissions to the air. This is in contrast to the
normally dry lath operations that finish the pipe ends.
Hydrotesting is a routine procedure in which the strength of the
pipe is tested while full of water under pressure. At some
plants, the hydrotest water is reused.
A pipe plant must remove solids from the bottom of the save-alls
to prevent their hardening into concretions. At some plants,
this dumping and clean up is carried out when the manufacturing
operations are shut down for the weekend. At other plants,
dumping occurs more frequently.
The reported waste water discharge from 10 of the 14 asbestos---
cement pipe plants ranges from 76 to 2,080 cubic meters per day
(0.02 to .55 MGD). The plants with minimal effluent volumes
discharge about 5.0 to 6.3 cu m per metric ton (1200 to 1500 gal
per ton) of product. The accuracy of these values is not known.
At a few locations, there is reduced discharge because of
evaporative losses from lagoons. Discharge records for a period
of a year or more were available at two pipe plants. At one
plant the minimum flow was 65 percent of the average and the
maximum was 145 percent. The flow figures included cooling water
from the manufacture of plastic pipe, however. The maximum
discharge at the other plant, which produced only asbestos-cement
45
-------
pipe, was 670 percent of the average. The standard deviation in
403 values at this plant was of the same magnitude as the average
flow.
waste Characteristics
The characteristics of raw waste waters from asbestos-cement pipe
manufacturing were developed from sampling data from three plants
and reported values from one plant that provides minimal
treatment. Two of the plants recirculated water from the
external treatment system back into the plant. These plants
tended to use relatively much more water and the dissolved
(filterable) solids levels were much higher in the waste waters
from these plants.
The manufacture of asbestos-cement pipe in a typical plant
increases the levels of the major constituents in the water by
the following approximate amounts:
Total solids
Suspended solids
BOD5 (5-day)
Alkalinity
1,500
500
2
700
kg/kkq
9
3.1
0.01
4.4
(Ib/ton)
18
6.3
0.02
8.8
The dissolved salts are reported to be primarily calcium and
potassium sulfates with lesser amounts of sodium chloride. The
magnesium levels are not known to be high. The alkalinity is
primarily caused by hydroxide with a small carbonate
contribution. The pH ranges as high as 12.9, but is generally
close to 12.0, or slightly lower.
Temperature—The temperature fluctuations at a given plant are
smaller than the differences between plants. The maximum raw
waste temperature measured in this study was 40 degrees C. This
plant recirculated some water from its treatment facility. The
average temperature at two other pipe plants were 10 to 15
degrees C hotter than the intake water.
Oil and grease—The oil and grease content of raw waste samples
taken at pipe plants was below detectable levels. Reported data
indicate that at some plants there are measurable oil and grease
levels in the final plant effluent. This is believed to be from
the equipment rather than the process.
Organic matter—The organic content of pipe plant waste waters is
normally low. Some plants use organic acids (acetic) to clean
the mandrels and to remove scale in the plant. This could
contribute BOD 5 to the waste stream. The waste acid is
neutralized when~mixed with the highly alkaline process waste
46
-------
stream.
forms.
The high pH precludes the presence of any biological
Plant nutrients—The measured and reported average levels of the
plant nutrients nitrogen and phosphorus in pipe plant effluents
were below 2.5 mg/1 and 0.05 mg/1, respectively. There are
unconfirmed peak values at individual plants of Kjeldahl nitrogen
values as high as 12 mg/1 and total phosphorus levels of 0.4
mg/1.
Other chemicals—The information on other constituents was
derived from reported data from a few individual plants. Most
plants did not have data on every constituent. Among the
constituents reportedly measured in the effluents from some
asbestos-cement pipe plants are chromium, cyanide, mercury,
phenols, and zinc. Based on the limited data available, the
levels were not judged to be significant.
Color and turbidity—The raw waste waters from pipe manufacture
are very turbid and of a gray-white color. When the solids are
removed, the water has no color.
Fluctuations—The variations in raw waste loadings from a typical
plant are not known. No plant measures or records the character-
istics of the raw waste waters. The waste water treatment
systems are designed on hydraulic principles and their
operational efficiency is largely independent of the strength of
the influent waste water.
The changes in waste characteristics associated with start-up of
a pipe plant are minor and less than the normal fluctuations
associated with operation. When a pipe plant is shut down and
the save-alls dumped, there is released a heavy charge of
suspended solids in a short period of time. Other parameters
remain the same or decrease slightly because of dilution by the
flush- water. Grab samples of raw pipe waste waters collected
during clean-up at one plant gave results in the following
ranges:
Total solids
Suspended solids
Alkalinity
1,400 to 3,100 mg/1
300 to 2,900 mg/1
540 to 2,000 mg/1
Fluctuations in raw waste water quality should not cause serious
problems in the physical treatment facilities appropriate for
pipe plant wastes.
ASBESTOS-CEMENT SHEET
Water Usage
47
-------
No information is known to be available about the internal water
balance in an asbestos-cement sheet plant. It is expected that
the percent recycle from the save-alls is roughly the same as for
asbestos-cement pipe (Figure 9) .
The reported waste water discharge from 4 of the 13 known sheet
plants ranges from 280 to 2,040 cubic meters per day (0.07 to .54
MGD) . The raw waste flows from the three sheet plants sampled
during this study were 570, 650, and 920 cu m/day (0.15, .17, and
.24 MGD). The largest of the three values was from a plant that
discharges no effluent and, consequently, may use relatively more
water. The minimal effluent volume from a plant was 7,5 cu m Fer
metric ton (1800 gal per ton) of production.
There are no known monitoring records of discharge from asbestos
- cement sheet plants and no estimate of the minimum, maximum,
and variability of the flow from a plant can be made.
Wast e Char act eri sties
The characteristics of raw waste waters from asbestos-cement
sheet manufacturing were developed from sampling data from two
plants. No other data were available except that reported by one
plant using the wet press forming technique to make high-density
sheet. Since this product may include pigments and other
additives and since it is produced at only two known locations,
neither of which have adequate data, it is not properly included
in this category,
The manufacture of asbestos-cement sheet products in a typical
plant increases the level of constituents in the water by the
following approximate amounts:
Total solids
Suspended solids
BOD5 (5-day)
Alkalinity
mg/l
2,000
850
2
1,000
kg/kkg_
15
6.5
0.015
7.5
30
13
0.03
15
Little information is available on the dissolved salts in sheet
wastewaters, but they should be similar to those from asbestos-
cement pipe manufacture. The alkalinity is caused primarily by
hydroxide with a pH averaging 11.7 and ranging from 11,4 to 12.4
in all reporting plants.
Temperature—Meaningful temperature data was available from only
one sheet plant. With a flow of 920 cu m/day (0.24 MGD), the
temperature was increased 13 degrees C in the sheet manufacturing
process. The reported peak summer temperatures of waste waters
discharged from asbestos-cement sheet plants was 50 degrees C.
48
-------
Oil and grease—The presence of oil and grease in waste waters
from sheet plants has not been reported. No measurable oil and
grease was found in the samples analyzed in this study.
Other constituents—The discussion regarding organic content,
plant nutrients, other chemicals, turbidity and color, and
fluctuations of the characteristics of asbestos-cement pipe waste
waters applies to those from asbestos-cement sheet.
ASBESTOS PAPER
Water Usage
The reported total waste water discharges from 5 of the 12
asbestos paper manufacturing plants range from 490 to 4,900 cubic
meters per day (0.13 to 1.3 MGD) . The accuracy of these values
is not known. The volumes of raw waste water discharged to the
treatment facility at two plants visited in connection with this
study were 1,700 and 2,700 cu m/day (0.45 and 0.72 MGD). Many
plants recirculate water and solids from the waste water
treatment facility to the paper making process and the effluent
volume is considerably less than the raw waste water discharge.
An effluent flow of 13.8 cu m per metric ton (3,300 gal. per ton)
was reported at the exemplary plants.
Information about variability of flow is available from one plant
only. This is the monitoring record of the treated effluent over
a recent eight-month period. The average flow was 490 cu m/day
(0.13 MGD) with minimum and maximum values of 430 and 755 cu
m/day (0.14 and .20 MGD), respectively. The standard deviation
of the 113 readings taken during the period was 53 cu m/day
(0.014 MGD). The exact quantities of water recycled from the
save-all system and from the waste treatment facility at this
plant are not known.
Waste Characteristics
The raw waste water characteristics from asbestos paper
manufacturing were developed from sampling data at two plants.
Both plants provide high levels of waste water treatment with low
volumes of effluent discharge. Consequently, the use of water
within these two plants may be higher than in plants that do not
recycle treated waste water.
Constituent--
The manufacture of asbestos paper in a typical plant increases
the levels of the constituents in the water by the following
approximate amounts:
49
-------
ma/I
kg/kkg
Total solids
Suspended Solids
BOD5 (5-day)
COD*
1,900
680
110
160
26
9,5
1*5
2.2
The pH of raw waste waters from asbestos paper
8.0 or lower.
52
19
3
4.4
manufacturing is
Temperature—The highest reported summer temperature value for
treated effluent is 32 degrees C. it is believed that heated
water is used in mixing the raw materials at most plants,
although at least one uses cold water. Recycled water tends to
have a higher temperature.
Oil and grease—Oil and grease was detected in only one of the
samples collected at the two paper manufacturing plants. The
level was low, 1.2 mg/lr and was believed to be from plant
equipment. This type of material is not part of the product
ingredients.
Organic matter—The oxygen demand is believed to be largely due
to the organic binders, i.e., starch or synthetic elastomers.
These latter innliirt** K£>vf*r;i1 ma-t-^i-ial « n-f Ai f ff>rt*r\+- r?hA* U W 11 I**** **•» fc* «b^«* *— «k *-**»J t^ ^H*«M t— .k. •_* m
include several materials of different chemical
Nutrients—The total nitrogen levels reported in effluents from a
few paper plants averaged 16 mg/1, with the Kjeldahl fraction
about 11 mg/1. Phosphorus levels ranged from 0.25 to 1.0 mg/1.
Other chemicals—Trace amounts of copper, mercury, and zinc were
reported to be in the wastes from individual asbestos paper
plants. The levels were judged not to be significant.
Color—The clarified waste waters are known to have some color.
The levels at two plants were 10 and 15 units.
Fluctuations—There was greater variability among the data from
the two paper plants than observed in most other asbestos
manufacturing operations. There are no data on the variations in
quality of raw asbestos paper waste waters other than the
sampling results and these were from too limited a period of time
to be of value. Results from the monitoring program at one paper
plant were cited above under Water usage. Although they refer to
treated effluent, they provide some indication of the variability
of the waste water characteristics, as follows:
Minimum
Total Solids 500 mg/1
Suspended Solids 32
BOD5 (5-day) 22
685 mg/1
64
57
Maximum Std_Devt'.n
870 mg/1 260 mg/1
95 44
91 48
50
-------
Unlike asbestos-cement products plants, asbestos paper plants do
not use portland cement and the solids in the save-alls do not
tend to form concretions. Shut-down is less regular and the
plants tend to operate around the clock. Shut-downs are
sometimes necessary when changing products. since the
elastomeric binders are not always compatible, the save-all
solids may be dumped at these times. There were no routine shut-
down or start-up operations while the paper plants were being
sampled in this study and there is no information on the
characteristics of the raw waste waters during these periods.
ASBESTOS MILLEOARD
There are seven known locations where asbestos millboard is
manufactured. At all of these locations, the waste waters are
either discharged to municipal sewers or are combined with other
asbestos manufacturing waste waters. Consequently, there is
almost no information from the industry about the quantity and
quality of millboard waste waters. The results presented below
are based primarily upon the sampling program carried out for
this study at two plants.
Water Usage
The water leaving the save-all systems at the two plants amounted
to Ul and 136 cubic meters per metric ton (12,000 and 39,500
gallons per ton). One plant discharges its waste waters to a
large lagoon system and recycles all of the lagoon effluent into
the plant. This is a multi-product plant. The other plant
normally recycles all of its save-all effluent. Surges due to
upsets or shut-down are released to a municipal sewer. Since
neither plant has any measurable effluent on a regular basis, the
amounts of water used in the manufacturing process may not be
representative of the amounts discharged by a plant that does not
recycle its waste water.
Waste Characteristics
Constituents-
At the plant that discharges its waste waters to the lagoon
system, the constituents added to the water were measured as
follows:
Suspended Solids
BOD5 (5-day)
JB2/I
35
5
kg/kkq
1.8
0.25
3.5
0.5
The total solids and COD levels in the water leaving the
millboard save-alls were the same as those of the make-up water.
The pH of the raw waste water ranged from 8.3 to 9.2. Some
millboard is manufactured with portland cement and the pH would
be higher in such cases.
-------
The effluent from the save-all system at the millboard plant that
operates with a completely closed water system had the character-
istics listed below. In such a plant, the waste constituents ac-
cumulate until a steady-state level is reached. The contribution
of each manufacturing cycle cannot be determined directly and,
consequently, raw waste loadings expressed in terms of production
units are meaningless.
Total solids
Suspended solids
BOD5 (5-day)
COD
Average
6,100 mg/1
5,100
2
62
Range
3,950 to 7,800 mg/1
3,060 to 6,270
10 to 145
The pH ranged from 11.8 to 12.1 and the alkalinity from 2,000
2,700 mg/1, mostly in the hydroxide form.
to
Temperature—The temperatures of the raw waste waters at the two
sampled millboard plants were 12 and 26 degrees C, with the
higher temperature measured at the completely closed system. The
highest reported summer temperature of the effluents at two other
millboard plants was 31 degrees C.
Other constituents—Small amounts of oil and grease, nitrogen,
and phosphorus were detected in some of the samples collected in
this study.
No information is available from the millboard industry on the
presence of plant nutrients, toxic constituent, or about the
nature of the additive materials that are used in the many
varieties of millboard.
Fluctuations—No information is available by which to accurately
estimate the degree of fluctuation in millboard waste water
characteristics. Judging from the differences in the two plants
that were sampled and from the relatively broad range of raw
materials used, the variability of waste waters from millboard
manufacture is high.
ASBESTOS ROOFING
Unlike the asbestos products covered previously, water is not an
integral part of roofing products, it is used, however, to cool
the roofing after saturation. All plants use non-contact cooling
and some use spray contact cooling. The roofing is largely, but
not completely, inert to water and the contact cooling water
becomes a process waste water. This contaminated cooling water
is discharged with the non-contact cooling water in some plants,
resulting in a large volume,of dilute process waste water.
Water Usage
52
-------
The discharge volumes vary widely among the few roofing plants
that reported information on flows, ranging from 145 to 2,100
liters per metric ton (35 to over 500 gallons per ton) of
product. The original temperature of the cooling water, whether
it is once-through or recirculated, and whether non-contact water
is included are factors influencing the reported amount of water
discharged. The fluctuations in flow rate should be minimal at a
given location.
Waste Characteristics
The characteristics of spent cooling water from roofing
manufacture are developed from sampling data taken at one plant.
This plant employs surface sprays and discharges the contact and
non- contact cooling water into a common sewer. The combined
waste water was sampled. At the time of sampling, the roofing
was being made from organic (non-asbestos) paper. Since the
water spray contacts only the outer bituminous surface and not
the base paper, it is believed that the samples are
representative of wastes from contact cooling of asbestos-based
roofing,
The added quantities of the major constituents were as follows:
Suspended solids
BOD5 (5-day)
COD
150
20
kq/kkq
0.06
0.003
0.008
0.13
0.005
0.016
The pH of the waste water averaged 8.2.
Temperature—The temperature of the spent cooling water was 13
degrees c, a 7-degree increase over the temperature of the intake
water at a flow rate of about 1,420 cubic meters per day (0.375
MGD) .
Supplemental data—Information about the effluents from- one other
asbestos roofing plant was reported by the manufacturer. The
waste water is treated by settling, oil skimming, and passage
through an adsorbant filter. The added quantities of materials
are reported to be:
Suspended solids
BOD5 (5-day)
COD
37
37
91
kq/kkg
0.06
0.07
0.15
0.12
0.13
0.30
The average pH of the effluent is reported to be 6.8.
Other constituents of interest were measured in this treated
effluent with the following average results in terms of added
quantities:
53
-------
Total Solids
Total Organic Carbon
Cyanide
Copper
Iron
Lead
Nickel
Zinc
Oil and Grease
Phenols
93
1
0.00003
0.019
0.031
0.001
0.003
0.071
1.6
0.003
g/kkcj
O.T6~
0*00015
0.00005
0.03
0.05
0.0015
0.005
0.12
0.0025
0.005
Total nitrogen and phosphorus levels in the cooling water were
each increased about 0.5 mg/1 by passage through the plant.
Arsenic, cadmium, and chromium were analyzed for, but not
detected in, the effluent.
The above information on treated roofing waste waters is
presented as supplemental data. It has not been verified, but it
does provide an insight into the strength and character of the
waste waters from asbestos roofing manufacture.
Fluctuations--There is insufficient information to describe
variations in the characteristics within a plant or among plants
in this category. Since the waste water is spent cooling water,
its characteristics should be unaffected by start-up and shut-
down operations.
ASBESTOS FLOOR TILE
From a water use and waste water characterization point of view,
vinyl and asphalt tile manufacturing both produce the same
result. Like roofing, water is used only for cooling purposes.
Both contact and non-contact cooling are usually employed. Water
does not come into contact with the tile until it has been heated
and rolled into its final form. In this stage it is completely
inert to water.
Hater,U^age
Cooling water usage information was available from six floor tile
plants with an average daily production of about 400,000 pieces.
The reported discharges ranged from about 80 to 1,700 liters (21
to 450 gallons) per 1,000 pieces with an average of 1,130 liters
(300 gallons).
The wide range reflects differences in intake water temperatures,
whether or not the water is recirculated, and whether both
contact and non-contact waters are included in the figures.
Because the water is used for cooling, fluctuations within a
given plant should not be large and should primarily be the
54
-------
result of changes in production levels or seasonal temperature
changes, or both.
Waste Characteristics
Despite the facte that floor tile itself is inert in water, the
contact cooling water becomes contaminated with a diverse variety
of materials including wax, inks, oil, glue, and miscellaneous
dirt and debris. The material has a high organic content
although the limited data available indicate that it is not
readily biodegradable.
Constituents-
The added waste constituents in a typical floor tile plant are as
follows:
Suspended Solids
BOD5 (5-day)
COD
150
15
300
0.18
0.02
0.36
(Ib/lQQQ^pc*)^
0.40
0.04
0.80
* pc- pieces of tile, 12"x12"x3/32"
The reported pH of,
8.'3, averaging 7.3.
tile plant waste waters ranges from 6.9 to
Temperature—The reported temperature data are inconsistent among
the few plants reporting. Some plants with large per unit flow
volumes show a larger temperature increase than plants with much
smaller flows per 1,000 pieces.
Oil and grease—Oil and grease are reportedly present in tile
plant effluents, with an average concentrations of 5.5 mg/1 after
treatment,
Organic matter—The COD is believed to be largely associated with
the suspended solids with much of it being wax.
Plant nutrients—The limited data on plant nutrients indicate
that the increased total nitrogen and phosphorus levels should be
less than 5.0 and 1.5 mg/1, respectively.
Other chemicals—Trace amounts of phenols and chromimum were each
reported by one plant. The levels were judged not to be
significant.
Color and turbidity—Data on the color and turbidity of waste
waters from floor tile manufacture are not available. The wastes
do have measurable levels of both parameters, however.
55
-------
Fluctuations—There are no known data by which to assess the
variations in constituent concentrations in waste waters from
floor tile plants.
56
-------
SECTION VI
SELECTION OF POLLUTANT PARAMETERS
SELECTED PARAMETERS
The chemical, physical, and biological parameters that define the
pollutant constituents in waste waters from the asbestos
manufacturing industry are the following:
Total suspended solids
BODS
COD" (or TOC)
pH
Temperature
Dissolved solids
Nitrogen
Phosphorus
Phenols
Heavy metals
The last four listed parameters are not normally present in high
concentrations. Individual plants have reported significant
levels of one or more in their effluents, however, and they are
therefore included.
Asbestos itself is not included in the list for several reasons.
The suspended solids present in the waste waters are to a large
extent asbestos fibers. Removal of suspended solids by
sedimentation will also remove asbestos fibers but there exists
no data at the present time on which to determine a definitive
relationship.
The agency is particularly concerned over the potential effects
of the discharge of asbestos fibers. It is therefore suggested
that the industry assess the extent of asbestos fiber discharges
in the effluent stream, after treatment and control, and take
appropriate additional measures to reduce such discharge.
Pollutants in non-process waste waters, such as discharges from
noncontact cooling systems, boiler blowdown, and wastes from
water treatment facilities are not included in this document.
The rationale for selection of the listed parameters is given
below. In the following paragraphs, the terms used to describe
the levels of the various parameters are relative within this
industrial category. For example, a BOD5 level of 100 mg/1 is
high for asbestos manufacturing waste waters, but is low compared
to many industrial wastes.
57
-------
MAJOR POLLUTANTS
The reasons for including the above listed parameters are briefly
presented below. The reader is referred to other sources
(Section XIII) for further descriptions of the parameters and
procedures for measuring them.
Total Suspended Solids
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, solids use a portion or all of the
58
-------
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.
The suspended solids levels in raw asbestos manufacturing waste
waters are often high with levels commonly in the 500 to 1,000
mg/1 range. The solids are heavy and settle quickly. They would
produce sludge deposits on the bottom of receiving water bodies
if discharged. The solids could also contribute turbidity and
possibly harm aquatic life if suspended in receiving waters. The
asbestos fiber content of the solids is reported to be relatively
low, with the bulk of the solids originating as cement, silica,
clay, and other raw materials.
Chemical_Qxygen Demand (COD)
Moderately high COD values are typically associated with raw
waste waters from asbestos paper, roofing, and floor tile
manufacturing. The binders used in paper are believed to be the
major source of COD. The elastomeric binders result in high COD
results, but contribute little BOD5. In other words, they are
not readily biodegradable. The COD in roofing waste waters is
caused by soluble bitumens, phenols, oil and grease from
bearings, and other materials that contaminate the contact
cooling water. It is believed that wax contributes the major
portion of COD in raw waste waters from floor tile production.
EH, Acidity and Alkalinity
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 works
structures, distribution lines, and household plumbing fixtures
and can thus add such constituents to drinking water as iron.
59
-------
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
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.
Raw waste waters from products that contain portland cement
normally have an elevated pH value. The pH of asbestos-cement
wastes is close to 12 or higher. This indicates a caustic
(hydroxide) alkalinity that should be neutralized before
discharge to receiving waters or municipal sewers. Highly
caustic waters are harmful to aquatic life.
OTHER POLLUTANTS
The following parameters were considered in the course of this
study. They were not included in the effluent guidelines and
standards for one or more of the following reasons: the amounts
found in the waste waters were insignificant, or insufficient
data was available upon which to base a limitation. In
particular, treatment to reduce dissolved solids levels is judged
to be beyond the scope of "best practicable" treatment based on
cost availability of the technology. Since the "best available"
treatment recommended is no discharge of process waste waters,
this constituent will be completely removed by 1983. Rationale
for establishing temperature limitations are presently not
available.
Biochemical Oxygen Demand (BOD)
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
60
-------
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 D.O. 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 fcod
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.
The BOD5 levels in wastes from asbestos-cement, roofing, and
floor tile product manufacture are usually very low. Important
BOD5 contributions originate with the natural organic binders
used in some asbestos papers and millboards. The typical maximum
levels are about 100 mg/1.
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
61
-------
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 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 benthinc organisms as a food source.
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
62
-------
the consumption of oxygen by putrefactive processes,
affecting the esthetic value of a water course.
thus
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.
Thermal increases are caused by chemical reactions, heating, and
contact cooling in various parts of the asbestos products
industry. Reported temperatures for effluents reach maximum
levels of 38 degrees c (100 degrees F). Recirculated water is
relatively hotter than that which is used once and discharged.
Dissolved Solids
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,
Many communities in the United States and in other countries use
water supplies containing 2000 to 4000 mg/1 of dissolved salts,
when no tetter 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.
63
-------
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.
In addition to the high suspended solids levels in most raw waste
waters from asbestos manufacture, the dissolved (filterable)
solids are often of equal or greater magnitude. These originate
primarily with the major raw materials, i.e., cement, clays, etc.
Sulfates are reported to be one of the major dissolved components
in the case of asbestos-cement products. The levels in seme
plant effluents are high enough to be of concern in public water
supplies if not adequately diluted by the receiving water.
Nitrogen and Phosphorus
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
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,
64
-------
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.
Nitrogen levels in raw waste waters from asbestos manufacturing
are normally not high, with reported maxima for total nitrogen of
about 15 ing/I. It is included here because nitrogen at this
level could influence eutrophication rates in some water bodies.
In some cases, the sources of nitrogen are the minor ingredients
and additives in the product, rather than the principal raw mate-
rials. These secondary ingredients are subject to change and the
nitrogen levels in the waste water should be monitored to insure
that excessive levels are absent.
Maximum phosphorus levels in asbestos waste waters are typically
in the 1 to 2 mg/1 range. Like nitrogen, this element can
influence eutrophication and should be monitored to insure that
levels are acceptably low.
Phenols
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, xhe 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.
The presence of measurable phenol levels have been reported in
wastes from roofing manufacture. These chemicals cause serious
taste and odors in water supplies and their entry to the waste
stream and should be maintained to insure that levels are
acceptably low.
65
-------
Heavy. Metals
Individual plants have reported that one or more of the following
metals were present in trace quantities in their effluents;
barium, cadmium, chromium, copper, mercury, nickel, and zinc.
Two pipe plants reported that cyanides were present in their
wastes. These materials were at levels well below those
specified as safe for drinking water. There was no consistent
pattern detected among the limited data available. These
materials may originate in the major raw materials or in the
minor ingredients and additives. Excessive effluent levels could
probably be most economically controlled by changing or
elimination of the source.
66
-------
SECTION VII
CONTROL AND TREATMENT TECHNOLOGY
INTRODUCTION
Those parts of the asbestos manufacturing industry covered in
this document fall into two groups: (1) asbestos-cement products
and asbestos paper and millboard, and (2) roofing and floor tile,
The waste waters from the second group are contaminated contact
cooling waters and are relatively smaller in volume. The level
and type of control and treatment measures for roofing and floor
tile plants are different than those for the product categories
in the first group. Most of the general material below applies
to the plants in the first group.
Char act eristics
The process waste waters from the manufacture of asbestos-cement
pipe , asbestos-cement sheet paper, and millboard represent the
major sources of pollutant constituents in the asbestos
manufacturing industry. The wastes originate from several points
in the manufacturing processes and they are usually combined into
a single discharge from the plant. The wastes from all of these
categories are similar in many characteristics and they are
amenable to treatment by the same operation, namely,
sedimentation. Because of similarities in manufacturing
processes, many in- plant control measures apply at all locations.
Treatment
Sedimentation, with various auxiliary operations, yields an
effluent of low pollution potential when properly applied to
asbestos manufacturing waste waters. The settled solids are
inert, dense, and appropriate for landfill disposal as described
in Section VIII. While present practices within the industry are
not achieving the best possible results in all cases, they can be
upgraded without major technical problems.
Treatment beyond sedimentation and pH control is not appropriate
for wastes from the major product categories in the asbestos
manufacturing industry. The only pollutant constituent remaining
at significant levels, other than temperature, is dissolved
solids. While these levels may be at undesirably high levels for
certain industrial water uses, they do not present serious
hazards to human health or to aquatic life. To remove the
dissolved solids burden in these waste waters would require
advanced treatment operations techniques, e.g., reverse osmosis,
electrodialysis, or distillation. The initial and annual costs
associated with these advanced treatment operations are so high
that alternative solutions, namely, complete recycle of waste
waters, will be implemented by the industry instead of further
treatment .
67
-------
During the course of the study carried out to prepare this docu-
ment, representatives of at least six of the companies listed in
Section III volunteered the information that complete recircula-
tion of process waste waters was presently under consideration,
being developed, or actively being implemented.
Implementation
The in-plant control measures and end-of~pipe treatment
technology outlined below can be implemented as necessary
throughout the asbestos manufacturing industry. Factors relating
to plant and equipment age, manufacturing process and capacity,
and land availability do not play a significant role in
determining whether or not a given plant can make the changes.
Implementation of a particular control or treatment 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.
IN-PLANT CONTROL MEASURES
Many asbestos manufacturing plants incorporate some in-plant
practices that reduce the release of pollutant constituents.
These practices have resulted in economic benefits, e.g., reduced
water supply or waste disposal costs, or both. Few plants
include all of the control measures that are possible, however.
Raw Materiaj, storage
Raw materials are normally stored indoors and kept dry. There
are no widespread water pollution problems related to improper
raw materials storage practices.
Waste Water Segregation
In all cases, sanitary sewage should be disposed of separately
from process waste waters. Public health considerations as well
as economic factors dictate that sanitary wastes not be combined
with asbestos process wastes.
Other non-process waste waters are often combined with
manufacturing wastes in asbestos plants. A careful evaluation
should be made in each plant to determine if some or all of these
wastes could be segregated and recirculated. Such reduction in
waste volumes might result in smaller, more economical waste
treatment facilities.
Housekeeping.Practices
Except for roofing and floor tile plants, housekeeping practices
do not greatly influence the waste water characteristics. The
use of wet clean-up techniques are common to control fiber and
dust air emissions. In view of the alternative, continuation of
68
-------
the proper use of such wet methods should not impair the
efficiency of end-of-pipe treatment facilities.
Water Usage_
Fresh water should be used first for pump seals, steam
generation, showers, and similar uses that cannot tolerate high
contaminant levels. The discharges from these uses should then
go into the manufacturing process as make-up water and elsewhere
where water quality is less critical.
Water conservation equipment and practices should be installed to
prevent overflows, spills, and leaks. Plumbing arrangements that
discourage the unnecessary use of fresh water should be
incorporated.
Plans should be made for complete recirculation of all waste
waters. This will permit the installation of new equipment and
the making of the plant alterations as part of an integrated,
long-range program. In some cases, it may be more economical for
a given plant to move directly toward complete recirculation
rather than install extensive treatment facilities.
In line with water use practices, evaluation of the benefits of
increased save-all capacity should be made at some plants. This
would provide more in-plant water storage, permit greater
operating flexibility, and reduce the level of pollutant
constituents in the raw waste waters discharged from the plant.
Product Categories
In-plant control measures applicable to specific asbestos product
manufacturing operations are given below.
Asbestos^cement Pipe-
Some pipe plants completely recirculate the water used in the
hydrotest operation. Some plants reuse part of the autoclave
condensate directly. Consideration should be given to piping
waste waters from wet saws to the save-all system.
At least one pipe plant recycles a major fraction of the effluent
from its waste treatment facility back into the manufacturing
process.
No plant making only asbestos-cement pipe has accomplished
complete recirculation. A reported experimental attempt to do so
by one company was not successful.
The raw waste water flow from asbestos-cement pipe manufacture is
typically in the range of U.I to 5.2 cubic meters per metric ton
(1200 to 1500 gallons per ton) of product.
Asbestos-cement Sheet Products-
69
-------
Many of the in-plant control measures described above for pipe
plants could be incorporated in sheet plants. The raw waste
water flow from sheet manufacture is typically in the range of
5.2 to 6.2 cu m/kkg (1500 to 1800 gal/ton).
One asbestos-cement sheet plant achieves complete recirculation
most of the time. The manufacturing process is so balanced that
the fresh water intake equals the amount of water in the wet pro-
duct. Fresh water enters the system only for boiler make-up and
as part of the vacuum pump seal water. This plant is connected
to a municipal sewer and excess flows caused by upsets and
process shut-downs are discharged intermittently. With
sufficient holding capacity to accommodate these surges,
discharge to the sewer could be eliminated.
The benefits of complete recycle at this plant include reduced
water cost and sewer service charges, minimal asbestos loss and,
reportedly, a somewhat stronger product.
The major problem encountered in complete water recycle at this
plant is scaling. Spray nozzles require occasional unplugging,
the water lines are scoured regularly with a pneumatically driven
cleaner, and fine sand is introduced into the pumps to eliminate
deposits.
While one sheet plant has accomplished almost complete recircula-
tion, this is not regarded as fully demonstrated technology.
This plant makes only a few asbestos-cement sheet products. The
intermittent discharge to the sewer does provide some blowdown
relief to the system. Whether such complete recirculation could
be applied to plants making sheet products with more stringent
quality specifications is not known. The progress at this plant
does indicate that complete recirculation is a realistic goal for
the future.
Asbestos Paper-
The in-plant control measures outlined above for asbestos-cement
pipe can be applied in part in asbestos paper making plants. One
paper plant has been able to close up its process water system
when making paper with a starch binder. Such operation is not
possible when elastomeric binders are used and excess water is
then discharged to the municipal sewer.
An asbestos paper plant that practices partial recycle of water
from its waste treatment unit typically discharges within 30 per-
cent of 11 cu m/kkg (3,300 gal/ton).
Partial recycle of water and underflow solids from the waste
water treatment facility is not uncommon in the asbestos paper
industry. Complete recirculation and zero discharge has not been
demonstrated on a continuing basis at any plant making only
paper. It is likely that paper could be manufactured using a
closed system if only starch binders were used. Total and
70
-------
continuous recycle of water and solids when using elastomeric
binders cannot be accomplished today. Since some paper plants
use both types of binders, a guideline based on the type of
binder used would be impractical.
That significant recycle of waste water has been accomplished
indicates that complete recirculation is a possible goal for the
future.
Asbestos Millboard-
One plant that produces a wide variety of millboard products with
a relatively small save-all system presently achieves almost
complete recycle of the process water. The stimulus at this
location was, at least in part, high costs for water and sewer
services. The plant releases save-all overflow to the municipal
sewer when upsets or product changes occur. With greater save-
all capacity or a holding tank, this plant could accomplish zero
discharge on a continuous basis.
In connection with this study, four of the seven known millboard
plants in the country were visited. Since almost complete recir-
culation has been demonstrated in a typical plant, it is believed
that zero discharge can be achieved soon by millboard
manufacturing plants.
Asbe stos Ropf ing-
The plants that practice contact cooling should evaluate the
possibility of eliminating this source of process waste water,
If this were done, and leaks and other losses o'f non-contact
cooling were closed and dry cleaning practices instituted, the
asbestos roofing industry would be able to operate without the
discharge of process waste waters.
In any case, non-contact cooling water and condensate should not
be mixed with contact cooling water. This practice greatly
increases the volume of process waste water to be treated.
Asbestos Floor Tile-
There are several in-plant measures that should be used in floor
tile plants to control the release of pollutant constituents.
Raw materials should be stored, measured, and mixed in an area
completely isolated from the cooling water systems. Only after
the ingredients are made into tile are they insoluble in water.
Toxic materials should be eliminated from the tile ingredients.
If possible, contact water cooling operations should be
eliminated. If this is not feasible, the contact cooling water
should be protected from contamination. Bearing leaks should be
controlled and escaping water protected from contact with wax,
oils, glue, and other dirt.
71
-------
If the contact cooling water and the non-contact cooling water
that escapes were prevented from becoming contaminated, it would
be much easier to treat. This contamination is unnecessary and
-the resulting process waste water is costly to treat.
TREATMENT TECHNOLOGY
Most asbestos manufacturing plants currently provide some form of
treatment of the raw waste waters before discharge to receiving
waters. In virtually all cases, this treatment is sedimentation.
At several plants, the treatment facilities are small and of
simple design. Fortunately the waste solids are dense and almost
any period of detention will accomplish major removal of the
pollutant load.
Technic^ considerations
sedimentation is the oldest of all treatment unit operations in
sanitary engineering practice. It is well understood and' its
costs, ease of operation, efficiency, and reliability make it
ideally suited for industrial application.
Application-
Sedimentation is an appropriate form of treatment for asbestos
manufacturing plant waste waters regardless of the plant size and
capacity, manufacturing process, or plant and equipment age.
Design is based on the hydraulic discharge and plants with
smaller effluent volumes can use smaller units. The treatment
system can be sized to accommodate surges and peak flows
efficiently. Because waste asbestos solids are inert
biologically, overdesign does not result in solids management
problems.
•
land ftequirements-
If necessary, complete settling facilities large enough to treat
the waste flows from any asbestos manufacturing plant can be
placed on an area of 0.1 hectare (0.25 acre) or less. If more
land is available, larger units that provide solids storage may
be constructed. Such units would result in lower operating
costs. This design is especially appropriate for waste waters
from asbestos- cement products manufacture because the solids are
inert. Solids with significant BOD5 levels may require more
prompt reuse or dewatering and disposal.
The land requirements for asbestos solids disposal are not exces-
sively high. Some plants have disposed of solids within
relatively limited boundaries for decades. While this practice
results in problems it does serve to indicate that land disposal,
if properly carried out as discussed in Section VIII, is an
72
-------
appropriate means of disposing of waste solids from asbestos
manufacturing.
Compatibility of Control, Measures-
The recommended end-of-pipe technology for the industry is
sedimentation, with ancillary operations as necessary. The
subsequent control technology recommended is complete
recirculation of all process waste waters from all categories of
asbestos manufacturing covered by this document- in most cases,
complete recycle will require that the save-all system be
expanded or supplemented to provide higher quality water for some
in-plant uses. The waste water treatment facility could very
readily serve this function.
Consequently, the recommended end-of-pipe control technology
would represent part of an overall long-term control program to
achieve zero discharge of pollutant constituents at most
locations.
Product Categories
Control and treatment technologies that are applicable to
specific product categories of the asbestos manufacturing
industry are described below.
Asbestos-Cement Products (A/C Pipe_ and A/C Sheet!
The applicable end-of-pipe technology for waste waters from the
manufacture of asbestos-cement products, both pipe and sheet, is
sedimentation and neutralization. Designs based on total
detention periods of 6 to 8 hours or loading levels of 24 cubic
meters per day per square meter (600 gallons per day per square
foot) of surface area yield effluent suspended solids levels of
30 mg/1 or lower.
Neutralization to a pH level of 9.0 or below has been achieved at
two locations in the industry by adding sulfuric acid or on-site
generated carbon dioxide. At both of these locations,
sedimentation precedes and follows neutralization.
The solids removed by the settling units are best dewatered by
gravity thickening. They are dense and biochemically inert and
are suitable for disposal by proper landfill disposal techniques.
To achieve complete recirculation of process waste waters, surge
capacity will have to be added to the water system. A
sedimentation unit cannot function in this capacity. A water
storage tank or reservoir would be required in the system. With
complete recycle, the neutralization operation will not be
required. Its function is to protect the receiving water. High
pH levels are not a problem in the manufacture of asbestos-cement
products. As noted in a previous section, additional scale
73
-------
control measures
implemented.
are necessary when complete recycle is
As noted above, complete recirculation of asbestos-cement sheet
process water has been demonstrated partially. Problems with
product strength have been reported in one effort to completely
recycle waste water from asbestos-cement pipe manufacture.
Additional research is needed to achieve this level of control.
Asbestos Paper—
The applicable end-of-pipe technology for waste waters from the
manufacture of asbestos paper is sedimentation preceded, as
necessary, by grit removal and coagulation with polyelectrolytes.
This treatment has been demonstrated at three or more locations.
Units designed for a loading of 24 cubic meters per day per
square meter (600 gallons per day per square foot) have achieved
suspended solids and BOD5 reductions to 25 mg/1 or less.
Most of the settled solids as well as part of the clarified water
should be recycled from the settling unit to the manufacturing
process at paper plants. The waste solids, which are normally
kept to a minimum, may be stored for later use or dewatered for
land disposal with the grit. Waste solids result, in part, from
the incompatibility of certain synthetic binders.
To achieve complete recycle of all process waste waters at
asbestos paper plants, surge capacity will be required. A water
storage tank will be required because the sedimentation unit
cannot provide this function.
As noted above, complete recirculation of asbestos paper process
water has been demonstrated partially when starch is used as the
binder. Additional research is needed to achieve this level of
control when using elastomeric binders.
Asbestos Millboard—
As discussed above under In-Plant controls, the applicable
control measure for asbestos millboard plants is complete recycle
of all process waste waters. No end-of-pipe technology is
specifically required if the plant"s save-all capacity is
adequate. Unlike settling tanks, save-alls can provide surge
capacity.
Waste solids will normally be generated only when the plant is
shut down. These will require dewatering and transportation to a
land disposal site. Since asbestos millboard manufacturing
operations are located in plants that make other asbestos
products, the best means of solids handling and disposal will be
dependent on the methods used for solids from the other product
lines.
74
-------
Asbestos Roofing—7
The applicable end-of-pipe technology for asbestos roofing waste
waters is sedimentation with skimming or filtration to remove
insoluble materials. Properly designed and operated facilities
should reduce the suspended solids levels to 15 mg/1 and COD to
20 mg/1 or less. If the organic materials are not adequately
removed, further treatment, possibly by activated carbon
adsorption, will be required. There is, at present, no informa-
tion available by which to assess the suitability or efficiency
of such treatment for these wastes. Information is lacking on
the nature of the dissolved organics in waste waters from
asbestos roofing manufacture.
To completely eliminate the discharge of pollutant constituents
will require that the contaminated cooling water that constitutes
the process waste water be treated, cooled, and reused. As noted
above, the precise type and extent of treatment required is not
known due to lack of information.
An alternative solution would be the elimination of contact
cooling and confinement of leaks so that the water remains
uncontaminated.
Asbestos FloorTile-
The applicable end-of-pipe technology for floor tile
manufacturing waste waters is sedimentation with coagulation and
skimming to remove suspended solids. It is believed that the
high COD levels associated with some tile plant wastes are caused
by insoluble materials. Properly designed and operated
facilities should reduce suspended solids levels to 30 mg/1 and
COD to 75 mg/1 or less.
The wastes from different tile plants are somewhat different and
the precise technology required to achieve these levels cannot be
predicted. At present, treatment beyond plain sedimentation and
skimming is not practiced by the industry. Sorption on activated
carbon following filtration should remove soluble organic
materials tc an acceptable level.
Complete elimination of the discharge of pollutants will
necessitate either cooling and reuse, or the use of non-contact
cooling water systems. No information is available by which to
determine the nature of the treatment best suited for the former
method.
75
-------
-------
SECTION VIII
COST, ENERGY, AND NON-WATER QUALITY ASPECTS
An analysis of the estimated costs and pollution reduction
benefits of alternative treatment and control technologies appli-
cable to the asbestos manufacturing industry is given in this
section.
The cost estimates were developed using data from various
sources, including that available from individual manufacturing
plants, contractor's files, and the general information in
Reference 13,17,19,and 20. The data supplied by industry were
limited in scope and applicability. Some of the costs were for
treatment systems or designs that were inadequate or
inappropriate for achieving the recommended effluent limitations.
At a few plants, the treatment facilities were either so old or
of such simple design that the cost information had little value.
REPRESENTATIVE PLANTS
The representative plants used to develop treatment cost
information were selected because of the relatively high quality
of the treatment facilities, the quantity of waste water
discharged, the availability of cost data, and the adequacy of
verified information about the effectiveness of the treatment
facility. The plants used typical, standard manufacturing
processes and incorporated some of the in-plant controls
described in Section VII. The waste flows were selected as being
typical for the larger plants in the category or subcategory. In
this regard, the flows used for sizing the treatment facilities
upon which the cost estimates were based were not necessarily the
average flows at the representative plants.
The end-of-pipe control technologies were designed, for cost
purposes, 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 somewhat different design, but equal efficiency,
could be used.
In summary, the cost information is intended to apply to most
plants in the category of subcategory. Differences in age or
size of production facilities, level of implementation of in-
plant controls, manufacturing process, and local non-water
quality environmental aspects all reduce to one basic variable,
the volume of waste water discharged.
77
-------
The representative asbestos manufacturing plants used for
developing cost estimates for the product categories and
subcategories are described in Table 3. As noted above, age and
size factors do not significantly influence costs.
COST INFORMATION
The investment and annual costs associated with the alternative
control technologies for the product categories, as well as the
effluent quality associated with each alternative, are summarized
in Table H 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 figure was used for
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
interruptions 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, and, hence no cost, would be
involved for this item.
Capital Costs
The capital costs are calcualted, in all cases, as 8 percent of
the total investment costs. Consultations with representative 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 for 20 years,
total investment cost, is used in all cases,
ri and Maintenance Cog-fes
or 5 percent of the
Operation and maintenance costs include labor, materials, solid
waste disposal, effluent monitoring, added administrative
expenses, taxes, and insurance* When the control technology
involved water recycling, a credit of $0.30 per 1000 gallons was
applied to reduce the operation and maintenance costs. Manpower
requirements were based upon information supplied by the
representative plants as far as possible. A total salary cost of
78
-------
TABLE 3
REPRESENTATIVE MANUFACTURING PLANTS USED IN
DEVELOPING COST INFORMATION
Product
Asbestos-Cement Pipe
Asbestos-Cement Sheet
Asbestos Paper
Asbestos Millboard
Asbestos Roofing
Asbestos Floor Tile
Dally Production
kkg
145
109
64
13.5
650
700,000
(Tons)
160
(120)
(70)
(15)
(720)
pc
Wastewater
Actual
cu m/day (mgd)
2,100 0.56
650 (0.17)
2,700 (0.72)
680 (0.18)
1,400 (0.37)
1,600 (0.43)
Flow
Design
cu m/day
1,990
470
1,990
380
1,500
1,500
(mgd)
(0.50)
(0.125)
(0.50)
(0.10)
(0.40)
(0.40)
*Design flow used in developing cost estimates
-------
$10 per man-hour was used 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 plants.
No useful information was available for the costs of solid waste
disposal for millboard and roofing manufacture.
and Power Costs
Power costs were estimated on the basis of $0.025
hour.
per kilowatt-
TREATMENT OR CONTROL TECHNOLOGIES WITH COSTS
Asbestos-Cement Pipe
Alternative.A - No Waste Treatment or Control
Effluent waste load is estimated to be 3.1 kg/kkg (6.3 Ib/ton) of
suspended solids, 4.4 kg/kkg (8.8 Ib/ton) of caustic (hydroxide)
alkalinity, and 6.3 kg/kkg (12.6 Ib/ton) of dissolved solids for
the selected typical plant at this minimal control level. The pH
of the untreated waste is 12.0. In-plant use of save-alls is
assumed, as this is universally practiced in the industry.
Costs. None.
Reduction Benefits. None.
Alternative B - Sedimentation of Process Wastes
This alternative includes settling of all process waste waters.
some form of sedimentation is applied at almost all plants in the
industry. Costs include land disposal of dewatered sludge.
Effluent suspended solids load estimated to be 0.19 kg/kkg (0.38
Ib/ton). Alkalinity,
pH, and dissolved solids remain high.
costs. Investment costs are approximately $124,000.
Reduction Benefits. Effluent suspended solids reduction
of approximately 94 percent*
Alternative _C - Sedimentation and Neutralization of Process
Wastes
This alternative includes settling of all -process waste waters
before and after neutralization to pH 9.0 or below. This
alternative is practiced presently by about 30 percent of the
pipe plants. Effluent suspended solids load of less than 0.19
80
-------
kg/kkg (0.38 Ib/ton), caustic alkalinity removed,
solids reduced somewhat.
and dissolved
Costs. Incremental costs are approximately $77,000 over
Alternative B; total costs are $201,000.
Reduction Benefits. Reduction of effluent suspended
solids of at least 95 percent, caustic alkalinity of
almost 100 percent, and an indeterminate reduction in
dissolved solids.
<ernative_p - Complete Recycle of Process Water
This alternative includes complete recycle of all process power
wastewaters back into the manufacturing processes and other in-
plant uses. Fresh water taken into plant equals quantity leaving
in wet product and other evaporative losses, complete control of
pollutant constituents without discharge is effected. No plant
making only pipe presently recycles all of the process wastes.
Costs. Incremental costs are approximately $104,000 over
Alternative C; total costs are $305,000.
Reduction Benefits. Reduction of all pollutant constitu-
ents, including suspended and dissolved solids and
alkalinity, of 100 percent.
The annual costs and resulting effluent quality for each of the
four treatment alternatives for asbestos-cement pipe are
summarized in Table U. The cost-effectiveness relationship for
suspended solids removal is illustrated in Figure 10.
Asbestos-Cement Sheet Products
Alternative^ - No waste Treatment or Control
Effluent waste load is estimated to be 6.5 kg/kkg (13 Ib/ton) of
suspended solids, 7.5 kg/kkg (15 Ib/ton) of caustic (hydroxide)
alkalinity, and 8.5 kg/kkg (17 Ib/ton) of dissolved solids for
the selected typical plant at this minimal control level. The pH
of the untreated waste is 11.7 or higher. In-plant use of save-
alls is assumed, as this is universally practiced in the
industry.
costs. None. Reduction Benefits. None.
Alternatiye_B - Sedimentation of Process Wastes
This alternative includes settling of all process waste waters.
Some form of sedimentation is applied at most plants in the
industry. Costs include land disposal of the dewatered sludge.
Effluent suspended solids load estimated to be 0.23 kg/kkg (O.U5
Ib/ton) . Alkalinity, pH, and dissolved solids remain high.
81
-------
Table 4
TYPICAL PLANT
WATER EFFLUENT TREATMENT COSTS
ASBESTOS MANUFACTURING
Asbestos-Cement Pipe
Treatment or Control Technologies
Alternatives
1
\t
Investment
Annual Costs:
Capital Costs
Depreciation
Operating and Maintenance Costs
(excluding energy and power costs)
Energy and Power Costs
*
Total Annual Cost
Costs in thousands of dollars
Effluent Quality:
Raw
Effluent Constituents Waste
Parameters (Units') Load
Suspended Solids - kg/MT 3.1
Caustic Alkalinity - kg/MT 4.4
pH 12
Dissolved Solids - kg/MT 6.3
Suspended Solids - mg/1 500
Caustic Alkalinity - mg/1 700
Dissolved Solids - mg/1 1000
A B C
$124 . $201
;.r -9.9 16.1
6.2 10.1
63.8 87.8
2.8 7.0
82.7 121
Resulting Effluent
Levels
do 0.19 0.19
do 4.4 0
do 12 9.0
do 6.3 6.3-
d'o 30 30
do 700 0
do 1000 1000-
D
$305
24.4
15.3
98.3
11.9
149.9
0
0
0
0
0
0
-
82
-------
i
I
S
u.
O
O o
I
ASBESTOS-CEMENT
PIPE
..J
I
I
I
I
20 40 60 80
REMOVAL OF SUSPENDED SOLIDS - PERCENT
100
Figure 10
83
-------
Costs. Investment costs'are approximately $56,000.
Reduction Benefits. Effluent suspended solids reduction
of approximately 96 percent. •. -
Alternative C - Sedimentation ..anc3. Neutralization of Process Water
This alternative includes settling of all process waste waters
before and after neutralization to pH 9.0 or below. This
alternative is used by 10 percent or less of the sheet plants.
Effluent suspended solids load of less than 0.23 kg/kkg (0.45
Ib/ton), caustic alkalinity removed, and dissolved solids reduced
somewhat.
Costs. Incremental costs are approximately $36,000 over
Alternative B; total costs are $92,000.
Reduction Benefits. Reduction of effluent suspended
solids of at least 96 percent, caustic alkalinity of
almost 100 percent, and an indeterminate reduction in
dissolved solids.
.'i!'.
Alternative D - Complete Recycle of Process Water
This alternative includes complete recycle of .all process waste
waters back into the manufacturing processes or other in-plant
uses. Fresh water taken into plant equals .quantity leaving in
wet product and other evaporative losses. Complete control of
pollutant constituents without discharge is effected. One sheet
plant is known to accomplish complete recycle during routine
operation.
Costs., Incremental costs are approximately $59,000 over
Alternative C; total costs are $151,000.
Reduction Benefits. Reduction of all pollutant constitu-
ents, including suspended and dissolved solids and
alkalinity, of 100 percent.
The annual costs and resulting effluent quality for each of the
four technology or control alternatives for asbestos-cement sheet
products are presented in Table 5. The cost-effectiveness
relationship for suspended solids removal is illustrated in
Figure 11, .•..<••
Asl3e_stos_Pa£er (starch and Elastomeric)
Alternatiye_A - No;Waste Treatment or Control
Effluent waste load is estimated to be 9.5 kg/kkg (19 Ib/ton) of
suspended solids, 1.5 kg/kkg (3 Ib/ton)!of BOD5, and 16.5 kg/kkg
(33 lb/ ton) of dissolved solids for the selected typical plant
at this minimal control level. In-plant use of save-alls is
assumed, as this is universally practiced in the industry.
84
-------
Table 5
TYPICAL PLANT
WATER EFFLUENT TREATMENT GC6TS
' ASBESTOS MANUFACTURING
Asbestos-Cement Sheet
Treatment or Control Technologies
Alternatives
Investment
Annual Costs:
Capital Costs
Depreciation
Operating and Maintenance Costs
( excluding energy and power costs)
Energy and Power Costs
Total Annual Cost
Effluent Quality;
Raw
Effluent Constituents Waste
Parameters (Units} Load
Suspended Solids - kg/MT 6.5
Caustic Alkalinity - kg/MT 7.5
pH . 11.7
Dissolved Solids - kg/MT 8.5
Suspended Solids - mg/1 850
Caustic Alkalinity - mg/1 1000
Dissolved Solids - mg/1 1150
4 1
$56
4.5
2.8
41.4
2.8
51.5
£
$92
7.3
4.6
53.3
4.2
69.4
£
' $151
12.1
7.5
92.4
7.0
119.0
Resulting Effluent
Levels
do 0.23
do 7.5
do 11,7
do 8.5
do 30
do 1000
do 1150
0.23
0
9.0
8.5-
30
0
1150-
0
0
0
0
0
0
0
'Costs in thousands of dollars
85
-------
O
i
150t-
h
S *
(0
O 50
I
ASBESTOS - CEMENT
SHEET
20 40 60 80
REMOVAL OF SUSPENDED SOLIDS - PERCENT
r
I
I
I
I
I
I
I
I
I
I
J
100
Figure 11
86
-------
Costs. None.
Reduction Benefits. None.
Alternatiye_B - Sedimentation of Process Wastes
This alternative includes settling of all process waste waters.
Some form of sedimentation is applied at approximately 70 percent
of plants in the industry. Costs include land disposal of
dewatered sludge. Effluent load estimated to be 0.35 kg/kkg (0.7
Ib/ton) of suspended solids and of BOD5 and 16.5 kg/kkg (33
Ib/ton) of dissolved solids.
Costs. Investment costs are approximately $237,000.
Reduction Benefits. Estimated reduction of effluent
solids of 96 percent and BOD5 of 75 percent. Dissolved
solids remain unchanged.
Alternative C - Complete Recycle of Process Water
This alternative includes complete recycle of all process waste
waters back into the manufacturing processes and other in-plant
uses. Fresh water taken into plant equals quantity leaving in
wet product and other evaporative losses. Complete control of
pollutant constituents without discharge is effected. One paper
plant is known to achieve complete recycle when using starch
binder under routine conditions.
Costs. Incremental costs are approximately $57,000 over
Alternative B; total costs are $294,000.
Reduction Benefits. Reduction of all pollutant constitu-
ents, including suspended and dissolved solids and
BOD5, of 100 percent.
The estimated annual costs and effluent quality for each of the
alternatives for asbestos paper manufacturing waste waters are
given in Table 6. The cost-effectiveness curve for suspended
solids removal from asbestos paper waste waters is given in
Figure 12.
Asbestos Millboard
Alternative.A - No Waste Treatment or Control
Effluent waste load is estimated to be 1.8 kg/kkg (3.6 Ib/ton) of
suspended solids and 0.25 kg/kkg (0.5 Ib/ton) of BOD5 for the
selected typical plant at this minimal control level. In-plant
use of save-alls is assumed, as this is universally practiced in
the industry.
Costs. None. Reduction Benefits. None.
-------
Table 6
TYPICAL PIANT
WATER EFFLUENT TREATMENT COSTS
ASBESTOS MANUFACTURING
Asbestos Paper
Treatment or Control Technologies
Alternatives
it
Investment
*
Annual Costs:
Capital Costs
Depreciation
Operating and Maintenance Costs
( excluding energy and power costs)
Energy and Power Costs
•X-
Total Annual Cost
Costs in thousands of dollars
Effluent Quality:
Raw
Effluent Constituents Waste
Parameters (Units) Load
Suspended Solids - kg/MT 9.5
BOD (5-day) - kg/MT 1.5
Dissolved Solids - kg/MT 16.5
Suspended Solids - mg/1 700
BOD ( 5-day) - mg/1 110
Dissolved Solids - mg/1 1200
A I
$237
19
12
16
16
63
C
$294
24
15
44
16
99
Resulting Effluent
Levels
do 0.35
do 0.35
do 16.5
do 25
do 25
do 1200
0
0
0
0
0
0
88
-------
300+-
g 200-
ASBESTOS-PAPER
I
I
J
8 100 -
20 40 60 SO
REMOVAL OF SUSPENDED SOLIDS - PERCENT
100
Figure 12
-------
Aj,teypative B - Sedimentation of Process Wastes
This alternative includes settling of all process waste waters.
Some form of sedimentation is applied to at least 40 percent of
the plants. Costs include disposal of sludge. Effluent load
estimated to be 0.8 kg/kkg (1.6 Ib/ton) of suspended solids and
0.2 kg/kkg (0.4 Ib/ton) of BOD5.
Costs. Investment costs are approximately $40,000.
Reduction Benefits. Estimated reduction of effluent sus-
pended solids of 55 percent and BOD5 of 20 percent.
Alternative C - Complete Recycle of Process Water
This alternative includes complete recycle of all process waste
waters back into the manufacturing process and other in-plant
uses. Fresh water taken into plant equals the quantity in wet
product. Complete control of pollutant constituents without
discharge is effected. One millboard plant is known to achieve
complete recycle most of the time.
Costs. Incremental costs are approximately $12,000 over
Alternative B; total costs are $52,000.
Reduction Benefits. Reduction of suspended solids, BOD5,
and all other pollutant constituents of 100 percent.
The annual costs and resulting effluent quality for the treatment
or control technology alternatives for asbestos millboard are
summarized in Table 7. The cost-effectiveness relationship for
suspended solids removal is illustrated in Figure 13.
Asbestos Roofing
Alternative A - No waste Treatment or Control
Effluent waste load is estimated to be 0.06 kg/kkg (0.12 Ib/ton)
of suspended solids, 0.003 kg/kkg (0.006 Ib/ton) of BOD5, and
0.008 kg/kkg (0.016 Ib/ton) of COD for the selected typical'plant
at this minimal control level.
Costs. None.
Reduction Benefits. None.
Alternative B - Sedimentation of Process Wastes
(Contaminated Cooling Water)
This alternative includes settling of all process waste waters
(contaminated cooling water) with skimming or filtration as
necessary to remove suspended matter. Effluent load estimated to
be 0.006 kg/kkg (0.012 Ib/ton) of suspended solids. BOD5 and COD
waste loads remain the same as Alternative A.
90
-------
Table 7
TYPICAL PLAOT
WATER EFFLUENT TREATMENT COSTS
ASBESTOS MANUFACTURING
Asbestos Millboard
Treatment or Control Technologies
Investment
Annual Costs:
Capital Costs
Depreciation
Operating and Maintenance Costs
(excluding energy and power costs)
Energy and Power Costs
Alternatives
A B C
$40
$52
3.2
2.0
31.0
5.0
4.2
2.6
24.3
7.0
Total Annual Costs
Costs in thousands of dollars
41.2
Effluent Quality:
Effluent Constituents
Parameters (Units)
Suspended Solids - kg/to
BOD (5-day) - Isg/MT
Suspended Solids - mg/1
BOD (5-day) - mg/1
Raw
Waste
Load
l.S
0.25
35
5
Resulting Effluent
Levels
do
do
do
do
O.S
0.2
15
4
0
0
0
0
91
-------
COSTS FOR TYPICAL PLANT
THOUSANDS OF AUG. 1971 DOLLARS
M
cn
8
K>
H-
OQ
C
fl
(D
OJ
31
m
i*
CO
c
(0
s
Ill
m
H
I
I
I
I
I
I
I
8
-------
Costs. Investment costs are approximately $24,000,
Reduction Benefits. Estimated reduction of effluent sus-
pended solids of 90 percent.
Alternative^ - Complete Recycle of Process Water
This alternative includes treatment, cooling, and reuse of
process waste water (contaminated cooling water). No process
waste waters are discharged and complete control of pollutant
constituents is effected.
Costs. Incremental costs are approximately $24,000 over
Alternative B; total costs are $48,000,
Reduction Benefits. Reduction of suspended solids, BOD5,
and COD and all other pollutant constituents of 100
percent.
The annual costs and effluent quality associated with each of the
treatment or control alternatives for asbestos roofing are given
in Table 8. The cost-effectiveness curve for suspended solids
removal for asbestos roofing is shown in Figure 14.
Asbestos Floor Tile
Alternative^A - No Waste Treatment or Control
Effluent waste load is estimated to be 0.18 kg (0.38 Ib) of
suspended solids, 0.017 kg (0.04 Ib) of BOD5, and 0.34 kg (0.75
Ib) of COD per 1,000 pieces of tile manufactured at the selected
typical plant at this minimal control level.
Costs. None.
Reduction Benefits. None.
Alternatiye B - Coagulation and Sedimentation of
~ (Contaminated Cooling Water)
Process Wastes
This alternative includes polyelectrolyte coagulation and
sedimentation with skimming as necessary to remove suspended
matter. The percentage of tile plants applying this alternative
is not known, but is expected to be less than 25 percent. The
effluent load is estimated to be 0.04 kg (0.08 Ib) of suspended
solids and 0.09 kg (0.19) of COD per 1,000 pieces of tile
manufactured. The BOD5 load may be reduced somewhat.
Costs. Investment costs are approximately $52,000.
93
-------
Table 8
TYP-ICAL PLA.NT
WATER EFFLUENT TREATMENT COSTS
ASBESTOS MANUFACTURING
Asbestos Roofing
Treatment or Control Technologies
.j(.
Investment .. ....
Annual Costs: ;-
Capital Costs ..-• ..;:.'•,.; ,- '•
Depreciation
Operating and Maintenance Costs
(excluding energy and power costs)
Energy and Power Costs
Alternatives
A B C
.$24
2,0
1,2
6.0
1.3
4.0
2.4
0
2.0
Total Annual Costs
'Costs in thousands of .dollars
10.0
3.4
Effluent Quality:
Effluent Constituents
Parameters (Units)
Suspended Solids - kg/MT
BOD ( 5-day) - 3cg/MT
COD - kg/MT
Suspended Solids - mg/1
BOD ( 5-day) - mg/1
COD - mg/1
Raw
Waste
Load
0.06
0.003
O.OOS
150
6
20
Resulting Effluent
Levels
do
do
do
do
do
do
0.006
0.003
0.008
15
6
20
0
0
0
0
0
0
94
-------
s!
H. ^
£ 50
a °
E 3
s s
«- w
gi
8|
25 -
ASBESTOS - ROOFING
I
I
I
I
— J
I
I
20 40 60 80
REMOVAL OF SUSPENDED SOLIDS - PERCENT
100
Figure 14
95
-------
Reduction Benefits. Estimated reduction of effluent
suspended solids of 80 percent and COD of 75 percent.
Alternative C - complete Recycle of Process water (Contaminated
Cooling Water)
This alternative includes additional treatment by filtration,
cooling, and reuse of process waste waters (contaminated cooling
water). No process wastes are discharged and complete control of
pollutant constituents is effected.
Costs. Incremental costs are approximately $58,000 over
Alternative B; total costs are $110,000.
Reduction Benefits. Reduction of suspended solids,
BOD5, and COD and all other pollutant constituents of
100"percent.
The annual costs and resulting effluent quality for each of the
three treatment or control technology alternatives , for asbestos
floor tile are summarized in Table 9.
The cost-effectiveness curve for suspended solids removal from
waste waters from floor tile manufacturing is illustrated in
Figure 15.
ENERGY REQUIREMENTS OF TREATMENT AND CONTROL TECHNOLOGIES
The energy required to implement in-plant control measures at a
typical asbestos manufacturing plant is 20 kw (25 Hp) or less.
The energy requirement is primarily for pumping to recycle and
reuse water.
The energy requirements of the end-of-pipe treatment technology
are not high for a typical plant. No aeration or heating
operations are involved. The single largest energy use would be
a centrifuge for dewatering waste solids from a paper or
millboard plant. This would be used only intermittently and
would require no more than 30 to 40 kw when running. The motors
for the sludge mechanisms in clarifiers are normally small, 5 kw
or less, and the pumping energy requirements would be similar in
magnitude to those for in-plant controls.
It is estimated that the total energy requirements for in-plant
control and end-of-pipe treatment technology at a typical
asbestos manufacturing plant would not exceed 50 kw on a
sustained basis.
No information was provided by the industry relative to the
energy requirements of individual manufacturing plants. Most
96
-------
Table 9
TYPICAL PIANT
WATER EFFLUENT TREATMENT COSTS
ASBESTOS MANUFACTURING '
Asbestos Floor Tile
Treatment or Control Technologies
Alternatives
Investment
Annual Costs:
Capital Costs
Depreciation
Operating and Maintenance Costs
( excluding energy and power costs)
Energy and Power Costs
it
Total Annual Cost
Costs in thousands of dollars
Effluent Quality:
Raw
Effluent Constituents Waste
Parameters ( Units') Load
Suspended Solids - kg/1000 pc 0.13
BOD (5-day) - kg/1000 pc 0.017
COD - kg/1000 pc 0.34
Suspended Solids - mg/1 150
BOD ( 5-day) - mg/1 15
COD - mg/1 230
A B
$52
4.2
2.6
11.0
1.8
19.6
C
$110
8.3
5.5
10.8
3.0
28.1
Resulting Effluent
Levels
do 0.04
do 0.017-
do 0.09
do 30
do 15-
do 75
0
0
0
0
0
0
97
-------
I
S> tOO
g *
il50^
o 52
o 5
ASBESTOS
FLDOU TILB
I
I
J
I
I
I
20 40 60 80
REMOVAL OF SUSPENDED SOLIDS - PERCENT
100
Figure 15
98
-------
involve steam generation for heating, for autoclaves, and for
product drying. The additional energy required to implement the
control and treatment technologies is estimated to be less than
10 percent of the requirements of the manufacturing and
associated operations.
NON-WATER QUALITY ASPECTS OF TREATMENT AND CONTROL TECHNOLOGIES
Air Pollution
The only significant potential air pollution problem associated
with the application of waste water treatment and control
technologies at a typical asbestos manufacturing plant is the
release of asbestos fibers and other particulates from improperly
managed solid residues. Exposed accumulations of dried solids
may serve as sources of air emissions upon weathering.
The biodegradable organic matter content of asbestos solids is
low or non-existent. The solids do not! undergo appreciable
microbial breakdown and there are no odor problems associated
with asbestos wastes.
There are no unusual or uncontrollable sources of noise
associated with application of the treatment and control
technologies.
Solid Waste Disposal
Solid waste control must be considered. The waterborne wastes
from the asbestos industry may contain a considerable volume of
asbestos particles as a part of the suspended solids pollutant
except for the roofing and floor tile subcategories. Best
practicable control technology and best available control
technology as they are known today require disposal of the
pollutants removed from waste waters in this industry in the form
of solid wastes and liquid concentrates. In some cases these are
non-hazardous substances requiring only minimal custodial care.
However, some constituents may be hazardous and may require
special consideration. In order to ensure long term protection
of the enviornment from these hazardous or harmful constituents,
special consideration of disposal sites must be made. All
landfill sites where such hazardous wastes are disposed should be
selected so as to prevent horizontal and vertical migration of
these contaminants to ground or surface waters, in cases where
geologic conditions may not reasonably ensure this, adequate
legal and mechanical precautions (e.g. impervious liners) should
be taken to ensure long term protection to the environment from
hazardous materials. Where appropriate the location of solid
hazardous materials disposal sites should be permanently recorded
in the appropriate office of legal jurisdiction.
Consideration should also be given to the manner in which the
solid waste is transferred to a industries waste disposal area.
99
-------
solids collected in clarifiers, save-alls or other sedimentation
basins should first be dewatered to sludge consistency.
Transportation of this asbestos containing sludge should be in a
close container or truck in the damp state so as to minimize air
dispersal due to blowing. Precautions should also be taken to
minimize air dispersal when the sludge is deposited at the waste
disposal areas.
The quantities of solids associated with treatment and control of
waste waters from paper, millboard, roofing, and floor tile manu-
facturing are extremely small. For example, the reported volume
of dewatered waste solids from a paper plant is 1.5 cu m (2 cu
yd) per month. Solids are wasted only when elastomeric binders
are being used, which is 25 to 35 percent of the time. Another
example is that provided by one of the larger floor tile plants
in the country. The sludge and skimmings from the sedimentation
unit amount to about 625 liters (165 gallons) per week. Unlike
other asbestos manufacturing wastes, this material is highly
organic and is disposed of by a commercial firm that incinerates
it. The treatment facility at this plant is not highly
efficient, but is believed to capture at least 50 percent of the
waste solids.
Contrary to the above categories, the waste solids associated
with asbestos-tcement product manufacture are significant in
volume. The reported losses at one pipe plant are in the order
of 5 to 10 percent of the weight of the raw materials. The
losses of asbestos fibers are kept to a minimum in this industry,
to 1 percent or less, and the fiber content of the waste solids
is low. The solids have no salvage or recovery value.
In summary, the solid wastes disposal associated with the
application of treatment and control technologies in the asbestos
manufacturing industry does not present any serious technical
problems. The wastes are amenable to proper landfill disposal.
Full application of control measures and treatment technology
will not result in major increases at most plants. In many
cases, complete recycle will result in lower losses of solids.
100
-------
SECTION IX
EFFLUENT REDUCTION ATTAINABLE THROUGH THE APPLICATION OF THE BEST
PRACTICABLE CONTROL TECHNOLOGY CURRENTLY AVAILABLE EFFLUENT
LIMITATIONS GUIDELNES
INTRODUCTION
The effluent limitations which must be achieved 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 the
asbestos manufacturing industry, but based upon performance
levels achieved by exemplary plants.
Consideration must also be given to:
a. The total costs of application of 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. processes changes; and,
g. the engineering aspects of the application of various
types of control techniques.
Also, Best Practicable Control Technology Currently Available em-
phasizes 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 instal-
lation of the control facilities.
101
-------
EFFLUENT REDUCTION ATTAINABLE THROUGH THE APPLICATION
PRACTICABLE CONTROL TECHNOLOGY CURRENTLY AVAILABLE
OF EEST
Based on the information contained in Sections III through VIII
of this document, a determination has been made of the degree of
effluent reduction attainable through the application of the Best
Pollution Control Technology Currently Available for the asbestos
manufacturing industry. The effluent reductions are summarized
here.
Suspended solids
The principal pollutant constituent in waste waters from the
manufacture of asbestos-cement products and asbestos paper and
millboard is suspended solids. Application of this control
technology will reduce suspended solids levels by at least 95
percent.
The relatively lesser suspended solids from asbestos roofing and
floor tile manufacture will be reduced by 90 and 80 percent, re-
spectively, by the application of this control technology.
Caustic Alkalinity
Waste waters from asbestos-cement product manufacture are highly
caustic. Application of this control technology will reduce the
caustic alkalinity by 100 percent. The pH will be 9.0 or below.
Oxygen Demanding Materials
Waste waters from asbestos paper and floor tile manufacture may
contain organic constituents that exert an oxygen demand; BOD5 or
COD in the case of paper wastes and COD in floor tile wastes.
Application of this control technology will reduce the oxygen
demand by 75 percent.
Pissolved Solids
Asbestos manufacturing may raise the dissolved solids level in
water significantly, especially in the case of asbestos-cement
products.
Application of this control technology will reduce the dissolved
solids by an indeterminate amount. The dissolved solids in the
treated effluent will still be relatively high.
Asbestos manufacturing operations increase the water temperature
to maximum levels of UO degrees C. Application of this control
technology will not result in significant temperature reduction.
102
-------
IDENTIFICATION
AVAILABLE
OF BEST PRACTICABLE CONTROL TECHNOLOGY CURRENTLY
In-plant control measures available to the asbestos manufacturing
industry will not significantly reduce the level of pollutant
constituents in the effluent. Application of such measures may
result in economic benefits and reduced end-of-pipe treatment
costs.
The Best practicable Control Technology Currently Available for
the categories of the asbestos manufacturing industry is
summarized below. There are no limitations on BOD5 and only two
subcategories have COD limitations. Treatment in the asbestos
industry is mainly sedimentation, the efficiency of which can be
adequately monitored using the total suspended solids parameter.
Also, since these limitations are absolute restrictions on
pollutants no credit is given for pollutants in waters entering
the processes. The BOD5 load in incoming water can be
substantial when compared to the BOD5 contributed by the process.
This is an additional reason for not including BOD5 in the
limitations.
However in the roofing and floor tile subcategories, the major
pollutants are organic and must be limited. This is accomplished
through sedimentation and skimming. Effluent concentration will
be low. Therefore, to allow in these specific cares for a COD
credit in incoming waters COD is defined as COD added to the
process waste waters. Monitoring will thus obviously entail
sampling of water entering the process and exiting the treatment
system.
Asbestos-Cement Pipe
The control technology is sedimentation and neutralization of all
process waste waters with land disposal of dewatered waste
solids. The recommended effluent limitations are as follows:
Suspended Solids
PH
Monthly._ Aver age
lii/ton
(0.38)
D aily Maximum
fib/ton}
0.19
6.0-9.0
0.57
6.0-9.0
The control technology is sedimentation and neutralization of all
process waste waters with land disposal of dewatered waste
solids. The recommended effluent limitations are as follows:
103
-------
Monthly Average
ki/kkg" ~ Jib/ton
Daily Maximum
kg/kkgTlb/tonj
Suspended Solids 0.23
pH 6.0-9,0
Asbestos Paper (Starch Binder)
(0.45)
0.68
6.0-9.0
(1.35)
The control technology is sedimentation, with coagulation if
necessary, of all process waste waters with land disposal of
dewatered waste solids. The recommended effluent limitations are
as follows:
Monthly Average
lib/ton.
(0.70)
Daily Maximum
kg/kkg ~ Jib/ton)
Suspended Solids 0.35
pH 6.0-9.0
Asbestos^Paper (Elastomeric Binder)
0.55
6.0-9.0
(1.10)
The control technology is sedimentation, with coagulation if
necessary, of all process waste waters with land disposal of
dewatered waste solids. The recommended effluent limitation are
as follows:
Mont^y Average
kq/kkq lib/ton.
Dai^y Maximum
Suspended solids
pH
0.35
6.0-9.0
(0.70)
0.55
6.0-9.0
(1.10)
Asbestos Mij.3,board
The control technology is no discharge of process waste waters to
navigable waters. In a plant that manufactures millboard and
other asbestos products, no increase in the limitations should be
allowed for the millboard in combined waste streams.
Asbestos Roofincr
The control technology is sedimentation, with skimming and
ancillary physical treatment operations if necessary, of all
process waste waters (contaminated cooling water). The
recommended effluent limitations are as follows:
104
-------
Daily Maximum
Jib/ton]
Monthly Average
]$S/kk3 " Jib/ton)
Suspended Solids
COD
PH
Asbestos Floor Tile
The control technology is sedimentation, with skimming if
necessary, or other physical treatment of all process waste
waters (contaminated cooling water). The recommended effluent
limitations are as follows:
0.006
0.008
6.0-9.0
(0.012)
(0.016)
0.010
0.015
6.0-9.0
(0.020)
(0. 029;
Monthly Average
Ilb/Mpc*).
Suspended Solids 0.04 (0.08)"
COD 0.09 (0.18)
pH 6.0-9.0
*Mpc * 1,000 pieces (12" x 12" x 3/32")
Daily Maximum
kg/Mp.c* ~ilb/ME£*
0.06 (0.13)
0.14
6.0-9.0
(0.30)
RATIONALE FOR THE SELECTION OF BEST PRACTICABLE CONTROL TECHNOLOGY
CURRENTLY AVAILABLE
Asbestos-cement Pipe
Sedimentation of process waste waters from asbestos-cement pipe
manufacture has been demonstrated to be effective in reducing
suspended solids concentrations to acceptable levels. No cheaper
alternative technology is available that is as effective as
sedimentation. The addition of either acid or carbon dioxide is
the most direct and least costly menthod of reducing the pH of
the waste waters to acceptable levels.
Costs and^Energy Beguirements-
The investment costs of implementing this level of control
technology are estimated to be $860,000 for all manufacturing
facilities in this subcategory. The added annual costs are
estimated to be $470,000. The additional energy requirements are
estimated to be 37 kw (50 hp) or less for the typical plant.
This power requirement represents only a small increment of the
total required for manufacturing.
Non-Water Quality Environmental Impact—
There is no evidence that application of this control technology
will result in any unusual air pollution or solid waste disposal
105
-------
problems, either in king or magnitude. The
problems in these areas are not excessive.
Size and Age of Eauipment^and Facilities—
costs of avoiding
As noted in section IV, the size range among asbestos-cement pipe
manufacturing facilities is relatively narrow. Differences in
size are insufficient to substantiate differences in control
technology. This level of control technology is readily
applicable to all facilities regardless of the age of the
equipment or the structure.
Processes Employed and Process Changes—
All facilities use similar manufacturing processes and produce
similar waste water discharges. There is no evidence that
operation of any process currently in use will substantially
affect capabilities to implement this control technology. The
implementation of this control technology does not require in*-
plant changes or modifications. Major developments in
manufacturing processes in the future are not expected. This
control technology can be applied so that upsets and other
fluctuations in process operations can be accomodated without
exceeding the effluent limitations.
Engineering Aspects of_Application;—
It is estimated that approximately 30 percent of the asbestos-
cement pipe manufacturing plants are currently using this ccntrol
technology. There are no plants making only pipe that achieve a
higher level of control. This was judged to be the average of
the best technology currently available in this subcategory. It
was determined to be an adequate level of control. Most plants
in this product subcategory provide some form of sedimentation,
without pH adjustment. Most of the treatment facilities will
have to upgrade in operations or capacity in order to achieve the
eflfuent limitations recommended in this document.
Asbesl:os-Cement sheet
Sedimentation of process waste waters from the manufacture of
asbestos-cement sheet products has been demonstrated to be
effective in reducing suspended solids concentrations to
acceptable levels. No cheaper alternative control technology is
more effective than sedimentation. The addition of either acid
or carbon dioxide is widely practiced in other industrial
categories to lower the pH of alkaline wastes to acceptable
levels. This operation can be applied to wastes from sheet
manufacture.
Costs and^Engerqy Requirements—
The investment costs of implementing this level of control
technology are estimated to be $640,000 for all manufacturing
106
-------
facilities in this subcategory. The annual costs are estimated
to be approximately $440,000. The additional energy requirements
are estimted to be 22 kw (30 hp) or less for the typical plant.
This power requirement represents only a small additional
increment of the total required for manufacturing.
Non-Water Quality Environmental Impact—
There is no evidence that application of this control technology
will result in any unusual air pollution or solid waste disposal
problems either in kind or magnitude. The costs of avoiding
problems in these areas are not excessive.
Size and Age of Equipment and Facilites—•
As noted in Section IV, the size range among asbestos-cement
sheet manufacturing facilities is relatively narrow. Differences
in size are insufficient to substantiate differences in control
technology. This level of control technology is readily
applicable to all facilities regardless of the age of the
equipment or the structure.
Processes Employed and Process Changes—
All facilities use similar manufacturing processes and produce a
similar waste water discharge. There is no evidence that
operation of any process currently in use will substantially
affect capabilities to implement this control technology. The
implmentation of this control technology does not require in-
plant changes or modifications. Major developments in
manufacturing processes in the future are not expected. This
control technology can be applied so that upsets and other
fluctuations in process operations can be accommodated without
exceeding the effluent limitations.
Engineering Aspects, of Application—
Approximatley 10 percent or less of the asbestos-cement sheet
products plants currently use this control technology fully.
Most plants in this subcategory provide some form of
sedimentation, but without pH adjustment to remove caustic
alkalinity. Such control is judged to be inadequate. Attainment
of the recommended suspended solids and BOD5 effluent limitations
has been demonstrated by plants within this subcategory.
Neutralization of alkaline waste is a treatment technology that
has been used successfully in many related industrial
applications and can readily be applied in asbestos-cement sheet
manufacturing.
Asbestos Paper {Starch and Elastomeric)
Sedimentation, with the use of coagulants in some cases, has been
demonstrated to be effective in reducing suspended solids and
107
-------
BOD5 concentrations to acceptable levels. No cheaper alternative
technology is available that is as effective as sedimentation.
Cost, and Energy Requirements—
The investment costs of implementing this control technology are
estimated to be $470,000 for all manufacturing facilities in this
product sufccategory. The added annual costs are estimated to fce
approximately $125,000. The additional energy requirements are
estimated to be 75 kw (100 hp) or less for the typical asbestos
paper plant. This represents only a small increment of the total
power required for manufacturing.
Non-Water Quality Environmental Impact—
There is no evidence that application of this control technology
will result in any unusual air pollution or solid waste disposal
problems, either in kind or magnitude. The costs of avoiding
problems in these areas are not excessive.
Size and Age of Equipment and Facilities—
As noted in Section IV, the size range among asbestos paper
manufacturing facilities is relatively narrow. Differences in
size are insufficient to substantiate differences in control
technology. This level of control technology is readily
applicable to all facilities regardless of the age of the
equipment or the structure.
Process Employed and Process .Changes--
All facilities use similar manufacturing processes and produce
similar waste water discharges. There is no evidence that
operation of any process currently in use will substantially
affect capabilities to implement this control technology. The
implementation of this control technology does not require in-
plant change s or modi f ication s. Ma j or development s in
manufacturing processes in the future are not expected. This
control technology can be applied so that upsets and other
fluctuations in process operations can be accommodated without
exceeding the effluent limitations.
Engineering .Aspects of Application—
It is estimated that 70 percent of the asbestos paper
manufacturing plants in the country use sedimentation facilities
in addition to in-plant save-alls. Some of the treatment units
will have to be upgraded in operation or capacity or both in
order to achieve the effluent limitations recommended in this
document. This level of control is judged to be adequate and is
the average of the best in the industry. Only one plant is known
to manufacture only asbestos paper and achieve a higher level of
control.
108
-------
Asbestos Millfcgard_
No discharge of process waste waters has been achieved by two of
the seven know millboard manufacturing facilities in the country,
This level of control technology is judged to be applicable to
all millboard plants that discharge to navigable waters.
Costs and Energy Requirements—
The investment costs of implementing this level of control
technology are estimated to be $260,000 for all manufacturing
facilities in this subcategory. The added annual costs are
estimated to be $191,000. The additional energy requirements are
estimated to be 37 kw (50 hp) or less for the typical plant.
This represents only a small additional increment of the total
power required for manufacturing.
Non-Water Quality Environmental Impact—
There is no evidence that application of this control technology
will result in any unusual air pollution or solid waste disposal
problems, either in kind or magnitude. The cost of avoiding
problems in these areas is not excessive.
Size and^Age of Equipment and Facilities—
As noted in Section IV, the size range among asbestos millboard
manufacturing facilities is relatively narrow. Differences in
size are insufficient to substantiate differences in control
technology. This level of control technology is readily
applicable to all facilities regardless of the age of the
equipment or the structure.
Processes Employed and Process Changes—
All facilities use similar manufacturing processes and produce
similar waste water discharges. There is no evidence that
operation of any process currently in use will substantially
affect capabilities to implement this control technology. The
implementation of this control technology does not require in-
plant changes or modifications. Major developments in
manufacturing processes in the future are not expected. This
control technology can be applied
fluctuations in process operations can
exceeding the effluent limitations.
so that upsets and other
be accommodated without
Engineering Aspects of Application—
As noted above, two of the seven millboard manufacturing
facilities in the country achieve complete recirculation of all
process waste1 waters. One plant uses a large lagoon, but the
other uses only save-all units. This level of control technology
is judged to be the average of the best and attainable by all
plants in this product subcategory.
109
-------
Asbestos Roofing
Sedimentation of process waste waters (contaminated cooling
water) from the manufacture of asbestos roofing products is
commonly practiced. Skimming and absorptive filtration is often
included to remove oils and other organic materials to acceptable
levels. This control technology is the least costly alternative
known to be effective with these wastes.
Costs and Energy Requirements—
The total investment costs of implementing this control
technology are estimated to be $120,000 for all manufacturing
facilities in this product subcategory. The added annual costs
are estimated to be $50,000. The additional energy requirements
are estimated to be 11 kw (15 hp) or less for the typical plant.
This power requirement represents only a small increment of the
total plant's energy needs.
Non-Water Quality Environmental Impact—
There is no evidence that application of this control technology
will result in any unusual air pollution or solid waste disposal
problems, either in kind or magnitude. The costs of avoiding
problems in these areas are not excessive.
Size and Age of Equipment and Facilities—
As noted in Section IV, the size range among asbestos roofing
manufacturing facilities is relatively narrow. Differences in
size are insufficient to substantiate differences in control
technology. This level of control technology is readily
applicable to all facilities regardless of the age of the
equipment or the structure.
Processes Employed and Process Changes—
All facilities use similar manufacturing processes and produce
similar waste water discharges. There is no evidence that
operation of any process currently in use will substantially
affect capabilities to implement this control technology. The
implementation of this control technology does not require in-
plant changes or modifications. Major developments in
manufacturing processes in the future are not expected. This
control technology can be applied so that upsets and other
fluctuations in process operations can be accommodated without
exceeding the effluent limitations.
Engineering Aspects of Application-^
It is estimated that approximately 35 percent of the asbestos
roofing manufacturing plants (saturation facilities) use this
control technology or the equivalent. This is the highest level
of control known to be used in treating waste waters in this
110
-------
product subcategory. This technology was judged to be the
average of the best and to be an adequate level of control. This
control technology is well understood and no unusual problems
should arise in applying it at all facilities in this subcategory
that discharge to navigable waters. Although the nature of the
waste are known imprecisely, the technology should be generally
effective in reducing the pollutant constituents to the levels
recommended in the effluent limitations.
Asbestos Flopr^Tile
The relatively limited data available on waste waters from floor
tile manufacturing indicate that most of the oxygen demand is
caused by insoluble materials that are removable by
sedimentation, aided perhaps by the use of coagulants. Within
this industrial category, there is no generally recognized
treatment technology that is normally applied. The plants that
do treat their wastes provide some form of sedimentation,
skimming, filtration, or chemical treatment or some combination
of these operations. Since the characteristics of the raw waste
waters is not well defined and may vary widely among plants, the
effectiveness of a given treatment technology at a particular
location cannot be predicted as accurately as is possible with
many industrial wastes.
Costs and Energy Requirements^
The total investment costs of implementing this level of control
technology are estimated to be $520,000 for all manufacturing
facilities in this subcategory. The added annual costs are
estimated to be $195,000. The additional energy required is
estimated to be 15 kw (20 hp) or less for the typical plant.
This represents only a small increment of the total power
requirement of a plant.
Non-Water Quality Environmental impact—
There is no evidence that application of this control technology
will result in any unusual air pollution or solid waste disposal
problems, either in kind or magnitude. The costs of avoiding
problems in these areas are not excessive.
Size and Acre of Equipment..and Facilities—
As noted in Section IV, the size range among asbestos floor tile
manufacturing facilities is relatively narrow. Differences in
size are insufficient to substantiate differences in control
technology. This level of control technology is readily
applicable to all facilities regardless of the age of the
equipment or the structure.
Processes Employed and Process Changes—
111
-------
All facilities use similar manufacturing processes and produce
similar waste water discharges. There is no evidence that
operation of any process currently in use will substantially
affect capabilities to implement this control technology. The
implementation of this control technology does not require in-
plant changes, or modifications. Major developments in
manufacturing processes in the future are not expected. This
control technology can be applied so that upsets and other
fluctuations in process operations can be accommodated without
exceeding the effluent limitations.
Engineering Aspects of Application—
It is estimated that about half of the asbestos floor tile plants
do not discharge to public sewerage systems are currently using
this level of control technology. From the limited data
available, this was judged to be an adequate level of control.
It was also judged to be the average of the best currently in use
fay this subcategory of the asbestos manufacturing industry.
112
-------
SECTION X
EFFLUENT REDUCTION ATTAINABLE THROUGH THE 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 where it is readily transferable from
one industry process 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;
g. the engineering aspects of the application of this control
The Best Available Technology Economically Achievable also
considers the availability of in-process controls as well as
control or 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
cost for this level of control is 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, this control technology may necessitate seme
industrially sponsored development work prior to its application.
113
-------
EFFLUENT REDUCTION ATTAINABLE THROUGH THE APPLICATION OF BEST
AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE
Based upon the information contained in Section III through VIII
of this document, a determination has been made that the degree
of effluent reduction attainable through the application of the
Best Available Technology Economically Achievable is no discharge
of process waste waters to navigable waters.
IDENTIFICATION
ACHIEVABLE
OF BEST AVAILABLE TECHNOLOGY ECONOMICALLY
This control technology for all subcategories of the asbestos
manufacturing industry is recycle and reuse of all process waters
and all cooling water that contacts the product or otherwise is
exposed to contamination fey pollutant constituents.
To implement this control technology requires that the quantity
of fresh water supplied to the plant for manufacturing purposes
equals the quantity leaving the plant with the product or that
lost through evaporation. A combination of in-plant control
measures to conserve water usage and end-of-pipe treatment
technology will be required at mpst plants to apply this control
technology;1
RATIONALE FpR THE SELECTION OF BEST AVAILABLE TECHNOLOGY
ECONOMICALLY ACHIEVABLE
AsbestQS~Ceme.nt_Pipe
No discharge of process waste waters represents the ultimate
level of control technology. All alternative technologies
whereby no discharge of pollutant constituents could be achieved
would be much more costly to implement.
Costs and Energy Requirements—
The total investment costs of implementing this level of control
technology lare estimated to be $1,900,000 for all manufacturing
facilities in this subcateogry, or $1,040,000 more than the Best
Practicable Control Technology Currently Available. The annual
costs are estimated to be approximately $760,000, an added
increment of $290,000. The energy requirements are estimated to
be 56 kw (75hp) or less for the typical plant. This represents
only a small increment of the total power required for
manufacturing.
Non-Water Quality Environmental Impact—
There is no evidence that application of this control technology
will result in any unusual air pollution or solid waste disposal
114
-------
problems, either in kind or magnitude. The
problems in -these areas-are not excessive.
Size and Aqen of Equipment and Facilities—
costs of avoiding
As noted in Section IV, the size range among manufacturing
facilities in this product subcategory is not large and this
control technology is equally applicable to all plants,
regardless of differences in size. The age of the equipment and
facilities also does not play a role in the applicability of this
level of control technology.
Processes Employed and Process Changes—
All facilities in this category use similar manufacturing
processes. There is no evidence that the minor process
variations that do exist will substantially affect the
applicability of this control technology. Some degree of change
of process operation will be involved in implementing this
technology and in-plant control measures will be required at most
facilities. Major new developments in manufacturing processes in
the future are not expected. This control technology can be
applied so that upsets and other changes in manufacturing
operations that result in fluctuations in waste volumes or
characteristics can " be accoraodated without exceeding the
recommended effluent limitations.
Engineering Aspects of Appligations—
The implementation of this control technology implies that the
quantity of fresh water taken into the manufacturing process be
balanced by that leaving with the product. The capacity of the
in-plant and end-of-pipe sedimentation units (save-allsr
clarifiers, etc.) must be adequate to accommodate all surges in
flow or additional holding tank volume will be required. This
presents no unus,ual engineering problems. Additional scale
control measures may be required.
There are two asbestos-cement pipe manufacturing facilities that
are know to recircualte treated process waste water through the
production line. Neither of these accomplish total recycle in
the strictest sense of the term, however. One is part of a
multi-product plant where all waste waters are treated and
recirculated without discharge of effluent. The other facility
recirculates much, but not all, of the treated waste water.
There is no plant making only pipe that accomplishes zero
discharge. Some problems relating to product quality were noted
in one experimental trial of total recycle at a pipe
manufacturing facility, and there is some element of risk
involved in establishing this level of control technology.
Additional research on the part of the industry will be necessary
to implement this technology.
Asbestos-Cement Sheet
115
-------
No discharge of process waste waters represents the ultimate
level of control technology. All alternative technologies
whereby no discharge of pollutant constituents could be achieved
would be much more costly to implement.
Costs and Energy Requirements--
The total investment costs of implementing this level of control
technology are estimated to be $1,290,000 for all manufacturing
facilities in this subcategory, or $650,000 more than the Best
Practicable Control Technology Currently Achievable. The annual
costs are estimated to be approximately $980,000, an added
increment of $540,000. The energy requirements are estimated to
be 37 kw (50 hp) or less for the typical plant. This represents
only a small increment of the total power required for
manufacturing.
Non-Water Quality Environmental Impact
There is no evidence that application of this control technology
will result in any unusual air pollution or solid waste disposal
problems, either in kind or magnitude. The costs of avoiding
problems in these areas are not excessive.
Size and Age of Equipment and Facilities—
As noted in Section IV, the size range among manufacturing
facilities in this product subcategory is not large and this
control technology is equally applicable to all plants,
regardless of differences in size. The age of the equipment and
facilities also does not play a role in the applicability of this
level of control technology.
Processes Employed and Process Changes—
All facilities in this subcategory use similar manufacturing
processes. There is no evidence that the minor process
variations that do exist will substantially affect the
applicability of this control technology. Some degree of change
of process operation will be involved in implementing this
technology and in-plant control measures will be required at most
facilities. Major new developments in manufacturing processes in
the future are not expected. This control technology can be
applied so that upsets and other changes in manufacturing
operations that result in fluctuations in waste volumes or
characteristics can be accommodated without exceeding the
recommended effluent limitations.
Engineering Aspects of Application—
The implementation of this control technology implies that the
quantity of fresh water taken into the manufacturing process be
balanced by that leaving with the product. The capacity of the
in-plant and end-of-pipe sedimentation units (save-alls.
116
-------
clarifiers, etc.) must be adequate to accomodate all surges in
flow or additional holding tank volume will be required. This
represents no unusual engineering problems. Additional scale
control measures may be required.
In addition to a sheet facility at the multi-product plant
mentioned in the previous discussion of asbestos-cement pipe,
there is one known asbestos-cement sheet products plant that
accomplishes zero discharge of process waste waters most of the
time. There are occasional periods when treated effluent
overflow to the municipal sewerage system. This plant
manufactures only a few of the many sheet products on the market
today using the wet mechanical process. To what extent complete
recirculation can be accomplished by all sheet plants making
other products and using other processes is not known. That one
plant has almost achieved zero discharge of pollutant
constituents serves as the basis for recommending this level of
control technology for this product subcategory.
Asbestos Paper
No discharge of process waste waters represents the ultimate
level of control technology. All alternative technologies
whereby no discharge of pollutant constituents could be achieved
would be much more costly to implement.
costs and Energy Requirements—
The total investment costs of implementing this level of control
technology are estimated to be $1,040,000 for all manufacturing
facilities in these subcategories, or $570,000 more than the Best
Practicable Control Technology Currently Achievable. The annual
costs are estimated to be approximately $400,000, an added
increment of $275,000. The energy requirements are estimated to
be 75 kw (100 hp) or less for the typical plant. This represents
only a small increment of the total power required for
manufacturing.
Non~Water Quality .Environmental Impact—
There is no evidence that application of this control technology
will result in any unusual air pollution or solid waste disposal
problems, either in kind or magnitude. The costs of avoiding
problems in these areas are not excessive.
Size and Age of Equipment and Facilities—
As noted in Section IV, the size range among manufacturing
facilities in these product subcategories is not large and this
control technology is equally applicable to all plants,
regardless of differences in size. The age of the equipment and
facilities also does not play a role in the applicability of this
level of control technology.
117
-------
Processes Employed and Process Changes—
All facilities in these subcategories use similar manufacturing
processes. There is no evidence that the minor process
variations that do exist will substantially affect the
applicability of this control technology. Some degree of change
of process operation will be involved in implementing this
technology and in-plant control measures will be required at most
facilities. Major new developments in manufacturing processes in
the future are not expected. This control technology can be
applied so that upsets and other changes in manufacturing
operations that result in fluctuations in waste volumes or
characteristics can be accommodated without exceeding the
recommended effluent limitations.
Engineering Aspects of Application—
The implementation of this control technology implies that the
quantity of fresh water taken into the manufacturing process be
balanced by that leaving with the products. The capacity of the
in-plant and end-of-pipe sedimentation units (save-alls,
clarifiers, etc.) must be adequate to accommodate all surges in
flow or additional holding tank volume will be required. This
presents no unusual engineering problems. Additional scale
control" measures may be required.
There are two known asbestos paper manufacturing facilities that
essentially achieve zero discharge. One is part of the multi-
product plant mentioned above and the other is a plant that makes
only paper. The former plant has no discharge and the latter has
no discharge under certain conditions. This plant is connected
to a public sewer and relief is available when necessary. Both
facilities use a starch binder. The second one also makes paper
with an elastomeric binder, when making this kind of paper*
treated waste water is discharged. Whether a plant using
elastomeric binders can achieve complete recirculation of all
waste water is unknown today. Research on the part of industry
will be necessary to detemine this. That complete recycle of
water has been demonstrated on a sustained basis in one major
segment of the asbestos paper manufacturing industry serves as
the basis for recommending this level of control technology.
Asbestos Millboard
The recommended technology is the same as that in Section IX of
the Document for Best Practicable control Technology Currently
Available. The rationale for this recommendation is fully
discussed there.
Asbestos Roofjng_
No discharge of process waste waters (contaminated cooling water)
represents the ultimate level of control technology. This can be
accomplished by treating and cooling the waste water and re-using
118
-------
it or by use of a totally non-contact cooling system with
containment of all leaks. The feasibility and costs of the
second alternative depend upon individual plant characteristics
and cannot be estimated. The discussion below applies,
therefore, to the first alternative.
Costs and Energy Requirements—
The total investment costs of implementing this level of control
technology are estimated to be $310,000 for all manufacturing
facilities in this subcategory, or $190,000 more than the Best
Practicable Control Technology Currently Achievable. The annual
costs are estimated to be approximately $37,000. This is less
than for the best practicable technology due to savings in fresh
water costs. The energy requirements are estimated to be 18 kw
(25 hp) or less for the typical plant. This represents only a
small increment of the total power required for manufacturing.
Non-Water Quality Environmental Impact--
There is no evidence that application of this control technology
will result in any unusual air pollution or solid waste disposal
problems, either in kind or magnitude. The costs of avoiding
problems in these areas are not excessive.
Size and Age of Equipment and Facilities—
As noted in Section IV, the size range among manufacturing
facilities in this product subcategory is not large and this
control technology is equally applicable to all plants,
regardless of differences in size. The age of the equipment and
facilities also does not play a role in the applicability of this
level of control technology.
Processes Employed and Process Changes-
All facilities in this subcategory use similar manufacturing
processes. There is no evidence that the minor process
variations that do exist will substantially affect the
applicability of this control technology. Some degree of change
of process operation will be involved and in-plant control
measures will be required at most facilities. Major new
developments in manufacturing processes in the future are not
expected. This control technology can be applied so that upsets
and other changes in manufacturing operations that result in
fluctuation in waste volumes or characteristics can be
accomodated without exceeding the recommended effluent
limitations.
Engineering Aspects.of Application—
There are no know asbestos roofing facilities (saturation plants)
that reuse the contaminated contact cooling water after
treatment. The full extents of the problems involved are not
119
-------
known, but technology is available from other industrial areas to
accomplish this level of control. Some facilities do not use
contact cooling systems. The feasibility of converting a contact
cooling system into a non-contact system is also not known.
Asbestos_Flfoqr Tile
No discharge of process waste waters (contaminated cooling water)
represents the ultimate level of control technology. This can be
accomplished by treating and cooling the waste water and reusing
it or by use of a total non-contact cooling system with
containment of all leaks. The feasibility and costs of the
second alternative depend upon individual plant characteristics
and cannot be estimated. The discussion below applies,
therefore, to the first alternative.
Costs, and Energy Requirements—
The total investment costs of implementing this level of control
technology are estimated to be $1,270,000 for all manufacturing
facilities in this subcategory, or $750,000 more than the Best
Practicable Control Technology Currently Achievable. The annual
costs are estimated to be approximately $310,000, an added
increment of $115,000. The energy requirements are estimated to
be 26 kw (35 hp) or less for the typical plant. This represents
only a small increment of the total power required for
manufacturing.
Non-Water Quality Environmental Impact—
There is no evidence that application of this control technology
will result in any unusual air pollution or solid waste disposal
problems, either in kind or magnitude. The costs of avoiding
problems in these areas are not excessive.
Size and Age of Equipment and Facilities—
As noted in Section IV, the size range among manufacturing
facilities in this products subcategory is not large and this
control technology is equally applicable to all plants,
regardless of differences in size. The age of the equipment and
facilities also does not play a role in the applicability of this
level of control technology.
Processes Employed and Process Changes—
All facilities in this subcategory use similar manufacturing
processes. There is no evidence that the minor process
variations that do exist will substantially affect the
applicability of this control technology. Some degree of change
of process operation will be involved in implementing this
technology and in-plant control measures will be required at most
facilities. Major new developments in manufacturing processes in
the futre are not expected. This control technology can be
120
-------
applied so that upsets and other changes in manufacturing
operations that result in fluctuations in waste volumes or
characteristics can be accomodated without exceeding the
recommended effluent limitations.
Engineering Aspects of Application—
There are no known asbestos floor tile manufacturing facilities
that reuse the contaminated contact cooling water after
treatment. This process waste water contains a wide variety of
materials and the precise treatment requirements are unknown.
The quantity of contact cooling water varies among facilities and
some reportedly do not use contact cooling. The feasibility of
converting a contact cooling system into a non-contact system is
undetermined.
121
-------
-------
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;
c. Process changes including changes in raw material
operating methods, and recovery of materials; and,
d. Engineering aspects of application
IDENTIFICATION OF NEW SOURCE PERFORMANCE STANDARDS
In the design and operation of new manufacturing facilitiees, in-
plant controls, and end-of-pipe technology will be required to
meet the recommended standards* In the summary below. Best
Practicable Technology Currently Available is identified as the
1977 level and Best Available Technology Economically Achievable,
as the 1983 level. The technologies are described in Section IX
and X for each product subcategory.
Asbestos-cement pipe
Asbestos cement sheet
Asbestos paper (starch binder)
Asbestos paper (elastomeric binder)
Asbestos millboard
Asbestos roofing
Asbestos floor tile
1977
1983
1983
1977
1977
1983
1983
123
-------
EFFLUENT REDUCTION ATTAINABLE THROUGH APPLICATION OF
PERFORMANCE STANDARDS
NEW SOURCE
Based on the information contained in Section III through VIII of
this document, a determination has been made of the degree of
effluent reduction attainable through application of the New
Source Performance Standards. These are fully outlined in the
appropriate parts of Section IX and X.
RATIONALE FOR THE SELECTION OF NEW SOURCE PERFORMANCE STANDARDS
Asbestos-cement Pipe
The factors considered in selecting the standard for new
asbestos-cement pipe manufacturing facilities are discussed
below.
Costs and Energy Requirements—
The costs of incorporating the necessary in-plant control and
end-of-pipe technologies into the design of a new facility should
be less than those for adding them in an existing plant. The
energy requirements should be the same or less.
Non-Water Quality Environmental.Impact—
There is no evidence that application of this standard will
result in any unusual air pollution or solid waste disposal
problems, either in kind or magnitude.
Process. Changes—
There are no changes in the basic manufacturing process available
that would achieve greater effluent reductions than attainable
through application of this standard. In-plant measures to
conserve water and materials should be incorporated into new
facilities. There are no significant benefits to be derived from
the use of batch operations or by the use of other raw materials.
There is currently a high degree of materials recovery from the
waste streams in facilities in this subcategory. The final
wastes have no known economic value and disposal on land by
appropriate methods will be necessary.
Engineering Aspects of Application—
It has not yet been demonstrated that an asbestos-pipe
manufacturing facility can accomplish complete recircualtion of
waste waters, or zero discharge of pollutants. For this reason,
the New source Performance Standard is Best Practicable Control
Technology Currently Available. As future developments dictate,
this standard may be revised.
124
-------
Asbestos-Cement Sheet
The factors considered in selecting the standard for new
asbestos- cement sheet manufacturing facilities are discussed
below.
Costs and Energy Requirements —
The costs of incorporating the necessary in-plant control and
end-of-pipe technologies into the design of a new facility should
be less than those for adding them in an existing plant. The
energy requirements should be the same or less,
Non-Water Quality Environmental Impact —
There is no evidence that application of this standard will
result in any unusual air pollution or solid waste disposal
problems, either in kind or magnitude.
There are no changes in the basic manufacturing process available
that would achieve greater effluent reduction than attainable
through application of this standards. In-plant measures to
conserve water and materials should be incorporated into new
facilities. There are no significant benefits to be derived from
the use of batch operations or by the use of other raw materials.
There is currently a high degree of materials recovery from the
waste streams in facilities in this subc&tegory. The final
wastes have nc known economic value and disposal on land by
appropriate methods will be necessary.
Engineering Aspects of Application —
One facility manufacturing asbestos-cement sheet products
essentially accomplishes zero discharge of pollutants. While
this is judged to be insufficient demonstration that all existing
sheet facilities can completely recycle all process waste waters
today, it is believed that new facilities can be designed to
achieve this level of control. Therefore, the New Source
Performance Standard is Best Available Technology Economically
Achievable.
Asbestos Paper (Starch and, Elastomeric)
The factors considered in selecting the standards for new
asbestos paper manufacturing facilities are discussed below.
Costs and Energy Requirements —
The costs of incorporating the necessary in-plant control
measures and end-of-pipe technologies to the design of new
facilities should be less than those for adding them in existing
plants. The energy requirements should be the same or less.
125
-------
Non-Water Quality Environmental_Impact —
There is no evidence that application of these standards will
result in any unusual air pollution or solid waste disposal
problems, either in kind or magnitude.
Process Changes- -
The different standards recommended for each of the asbestos
paper subcategori'es is necessitated by differences in raw
materials. When using elastomeric materials as binder, complete
recycle of waste waters has not been demonstrated. There is no
information available about possible changes in raw materials
that would permit complete recycle in elastomeric binder systems.
There are no changes in the basic manufacturing process available
that would achieve greater effluent reduction than attainable
through application of these standards. In-plant measures to
conserve water and materials should be incorporated into all new
facilities. There are no significant benefits to be derived from
the use of batch operations. There is currently a high degree of
materials recovery from the waste streams in facilities in these
subcategories .
Engineering Aspects imof Application —
No discharge of pollutants has been demonstrated at at least one
asbestos starch paper manufacturing facility. This serves as the
basis for recommending that the New Source Performance Standard
be Best Available Technology Economically Achievable for this
subcategory. Complete recycle has not been demonstrated by a
facility when making asbestos paper with an elastomeric binder,
Therefore, the New Source Performance Standards for these
facilities is Best Practicable Control Technology Currently
Available .
Asbestos Millboard
The factors considered in selecting the standard for new asbestos
millboard manufacturing facilities are discussed below.
cost and Energy Requirements —
The costs of incorporating the necessary in-plant control and
end-of-pipe technologies into the design of a new facility should
be less than those for adding them in an existing plant. The
energy requirements should be the same or less.
2u3j4tv Environmental jmpact —
There is no evidence that application of this standard will
result in any unusual air pollution or solid waste disposal
problems, either in kind or magnitude.
126
-------
Process Changes —
There are no changes in the basic manufacturing process available
that would achieve greater effluent reduction than attainable
through application of this standard. In-plant measures to
conserve water and materials should be incorporated into new
facilities. There are no significant benefits to be derived from
the use of batch operations or by the use of other raw materials.
There is currently a high degree of materials recovery from the
waste streams in facilities in this subcategory. The final
wastes have nc known economic value and disposal on land by
appropriate methods will be necessary.
gfogipee£J-n.cL^£e9ts of Application —
Complete recycle of process waste waters has been demonstrated by
facilites in the asbestos millboard category. Therefore, the New
Source Performance Standard is Best Practicable Control
Technology Currently Available, which is identical with Best
Available Technology Economically Achievable.
Asbestos Roof ing
The factors considered in selecting the standard for new asbestos
roofing manufacturing facilities are discussed below.
Costs andm Energy Requirements —
The costs of incorporating the necessary in-plant control and
end-of-pipe technologies into the design of a new facility should
be less than those for adding them in an existing plant. The
energy requirements should be the same or less.
Quality Environmental Impact —
There is no evidence that application of this standard will
result in any unusual air pollution or solid waste disposal
problems, either in kind or magitude.
There is some limited information available that indicates that
new asbestos roofing facilites could be designed to operate
without contact cooling water systems. No major changes in the
basic manufacturing process should be required to operate in this
manner. There are no significant benefits to be derived from the
use of batch manufacturing operations. Changes in raw materials
might be beneficial if treatment and reuse of the contaminated
cooling waters are determined to be the most feasible method of
meeting this standard. There is no information, however, about
raw materials that could be substituted. The materials in the
waste stream are present in low levels and contaminated form.
They have no significant economic value if recovered.
127
-------
Engineering Aspects of Application —
Complete recycle of contaminated cooling water has not teen
demonstrated by f acilites manufacturing asbestos roofing
products. It is believed that through either the use of control
technologies available in other industrial segments or by
elimination of contact cooling water systems, this level of
control can be achieved in new facilities. Therefore, the New
Source performance Standard is Best Available Technology
Economically Achievable.
The factors considered in selecting the standard for new asbestos
floor tile manufacturing facilities are discussed below,
Costs and Energy Requirements —
The costs of incorporating the necessary in-plant control and
end-of-pipe technologies into the design of a new facility should
be less than those for adding them in an existing plant. The
energy requirements should be the same or less.
Non-Water Quality Environmental Impact —
There is no evidence that application of this standard will
result in any unusual air pollution or solid waste disposal
problems, either in kind or magitude.
Several floor tile manufacturing facilities currently operate
with non-contact cooling water systems entirely. It is believed
that new facilities can incorporate such systems without
significant changes in process being necessary. Even with non-
contact cooling, in-plant control measures will be necessary to
reduce leakage to an acceptable level. Dry cleaning methods
should be used to reduce water usage.
Changes in raw materials would not affect any appreciable
effluent reduction. Materials recovered from the waste stream
have no known economic value.
Engineering Aspects of Application —
Complete recycle of contaminated cooling water has not been
demonstrated by facilities manufacturing asbestos floor tile
products. It is believed that through either the use of control
technologies available in other industrial segments or by
elimination of contact cooling water systems, this level of
control can be achieved in new facilities. Therefore, the New
Source Performance Standard is Best Available Technology
Economically Achievable.
128
-------
SECTION XII
ACKNOWLEDGEMENTS
The Environmental Protection Agency wishes to acknowledge the
contributions to this project by Sverdrup 5 Parcel and
Associates, Inc., St, Louis, Missouri. The work at Sverdrup 6
Parcel was performed under the direction of Dr. H.G. Schwartz,
Jr., Project Executive; Dr. James E. Buzzell, Jr., Project
Manager; and assisted by J.Winfred Robinson.
Appreciation is extended to the many people in the asbestos
manufacturing industry who cooperated in providing information
and data. The assistance of the Asbestos Information
Association-North America is appreciated.
Special mention is made of the following company representatives
who gave of their time in developing the information for this
document:
Mr. Edmund M. Fenner and Mr. Lucine D. Mutaw of the Johns-
Manville Corporation,
Mr. S.E. Monoky, Mr. Fred L. Bickel, and Mr. John P. McGinley of
the Certain-Teed Products Corporation,
Mr. W.C. Harper, Mr. Aubrey A. Serratt, Mr. A.W. Smith and Mr.
R.S. Miller of the Celotex Corporation,
Mr. E.A. Opila, Mr. Herbert A. Dalik, Mr. William Carl, Mr. Paul
Masek, and Mr. Ed Potkay of the Flintkote Company,
Mr. R.K. Wilson, Mr. W. H. Wolfinger, and Mr. M.A. Arvieta of the
Armstrong Cork Company,
Mr. Jack Holloway and Mr. Stan Stempien of the GAF Corporation,
and
Mr. J.J. Finnegan and Mr. H.L. Becker of Nicolet Industries, Inc.
Appreciation is expressed to those in the Environmental
Protection Agency who assisted in the performance of this
project: Acguanetta McNeal, John Riley, George Webster, c. Ronald
McSwinney, Ernst Hall, Arthur Mallon, and Edward Berg.
129
-------
-------
2.
3.
4.
5.
7.
8.
10
SECTION XIII
REFERENCES
Asbestos, Stover Publishing Company, Willow Grove, Pa.
Bowles, O., Tjie_Asbe stos_Industry , U.S. Bureau of Mines,
Bulletin 552.
Clifton, Robert A., "Asbestos," Bureau of Mines Minerals
Yearbook, U.S. Department of the Interior,
11
1 2
13
14
15
DuBois, Arthur B. , Air bor ne_Asbes tos , U.S. Department of
Commerce, 1971.
Impact of Proposed QSHA Standard for Asbestos, report to
U.S. Department of Labor by Arthur D. Little, Inc. 1972.
Industrial Waste Study Report: Flat Glass, Cement, Limef
QyP§um* and Asbestos industries, report to Environmental
Protection Agency by Sverdrup 6 Parcel and Associates, Inc.,
1971.
Knapp, Carol E., "Asbestos, Friend or Foe?11, Environmental
Science and Technology, Vol. 4, No. 9, 1970.
May, Timothy C., and Lewis, Richard W. , "Asbestos," Bureau
of Mines Bulletin 650. Mineral Facts and Problems ,
U.S. Department of the Interior, 1970.
McDermott, James H., "Asbestos in Water" Memorandum to __
Regional water Supply Representatives , U.S. Environment a 1
Protection Agency, April 24, 1973.
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." Archieve of Environmental
Health, Vol. 22, 1971.
Methods for Chemical Analysis _of Water and Wastes, Environmental
Protection Agency, National Environmental Research Center,
Analytical Quality Control Laboratory, Cincinnati, Ohio, 1971.
National Inventory of Sources and Emissions; Cadmium, Nickel
and Asbestos, report to National Air Pollution Control
Administration, Department of Health, Education and
Welfare, by W.E. Davis & Associates, 1970.
Patterson, W. L. and Banker, R, F., Estimating Costs
Rosato, D. V., Asbestos: Its Industrial Applications,
Reinhold Publishing Corporation, New York, N.Y, 1959.
Selikoff, Irving J., Hammond, E. Cuyler and Seidman, Herbert,
Cancer Risk of Insulation Workers in the United States ,
131
-------
International Agency for Research on Cancer, 1972.
16. Selikoff, Irving J., Nicholson, William J., and Langer,
Arthur M, , "Asbestos Air Pollution."
Archies of Environmental Health, Volume 25, American
Medical Association, 1972.
17. Sewage Treatment Plant and Sewer Construction Cost _In_dexes,
Environmental Protection Agency, Office of Water Programs
Operations Municiapl Waste wa,ter Systems Division,
Evaluation and Resource Control Branch.
18. Sinclair, W. E., Asbestos,_Its Qriginf Production and utilization,
London, Mining Publications Ltd., 1955.
19. Smith, Robert, Cost of Conventional and Advanced Treatment
of Waste waters. Federal Water Pollution Control
Administration, U.S. Department of the Interior, 1968.
20. Smith, Robert and McMichael, Walter F., Cost and Performance
lStimate£__for_Tertiary_ Waste water Treating_prpcesses,
Federal Water Pollution Control Administration, U.S.
Department of the Interior, 1969.
21- Standard Methods for the Examination of Water and Waste_water,
13th Edition, American Public Health Association,
Washington, D.C. 1971.
22. Sullivan, Ralph J., Air Pollution Aspects of _Asbestos. U.S.
Department of Commerce, 1969.
23. Tabershaw, I. R., "Asbestos as an Environmental Hazard,"
Journal of Occupational Medicine,1968.
2U. The Asbestos Factbook, Asbestos, Willow Grove, Pa., 1970
25. Villecro, M., "Technology, Danger of Asbestos," Architectural
Forumx 1970.
2^• Welcome.to the Johns-Manville Transite Pipe_Plant at Manyille,
ii£iI~J°hns-Manville Co77~New York7~N.Y.7 ^9697
27. Wright, G. W., "Asbestos and Health in 1969," American Review
of Respiratory Diseases, 1969.
132
-------
SECTION XIV
GLOSSARY
Beater
A wet mixer used to separate the fibers, mix the ingredients, and
provide a homogeneous slurry.
Binder
A chemical substance mixed with asbestos and other ingredients to
bond them together,
Blinding
The plugging by fibers and binder of the pores in carrier felts
and holes in cylinder screens thereby reducing or preventing the
flow of water through the felt or screen.
Calender
A machine designed to give paper a smooth surface by passing it
between a series of pressure rollers.
Elastomeric Paper
Paper made with a synthetic or natural rubber binder.
6- Felt
An endless belt of heavy porous cloth.
Mottle
Solid color granulated tile chips that are made and fed into tile
production lines to provide color and pattern.
Vacuum Box
A box with a long, narrow opening positioned just below or above
the felt in a paper machine. The vacuum maintained in the box
draws water out of the sheet of fiber through the felt and into
the box.
A rotating paddle designed to release fiber or other particulate
matter from a paper, pipe, or millboard machine carrier felt by
beating the felt as it moves through the machine.
133
-------
-------
TABLE 10
METRIC UNITS
CONVERSION TABLE
U)
Ui
MULTIPLY (ENGLISH UNITS)
ENGLISH UNIT ABBREVIATION
acre ac
acre - feet ac ft
British Thermal BTU
Unit
British Thermal BTU/lb
Unit/pound
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 lb
million gallons/day mgd
mile mi
pound/square inch psig
(gauge)
square feet sq ft
square inches sq in
tons (short) ton
yard yd
by
CONVERSION
0.405
1233.5
0.252
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
(0.06805 psig +1)*
0.0929
6.452
0.907
0.9144
TO OBTAIN (METRIC UNITS)
ABBREVIATION METRIC UNIT
ha hectares
cu m cubic meters
kg cal kilogram-calories
kg cal/kg kilogram calories/
kilogram
cu m/min cubic meters/minute
cu m/min cubic meters/minute
cu m cubic meters
1 liters
cu cm cubic centimeters
°C degree Centigrade
m meters
1 liters
I/sec liters/second
kw kilowatts
cm centimeters
atm atmospheres
kg kilograms
cu m/day cubic meters/day
km kilometer
atm atmospheres
(absolute)
sq m square meters
sq cm square centimeters
kkg metric tons
(1000 kilograms)
m meters
*Actual conversion, not a multiplier
------- |