EPA 44071-77/081-d
Supplemental For
PRETREATMENT
to the
Interim Final Development Document
for the
SECONDARY COPPER
Segment Of The
NONFERROUS METALS
MANUFACTURING
POINT SOURCE CATEGORY
U.S. ENVIRONMENTAL PROTECTION AGENCY
DECEMBER 1976
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SUPPLEMENT for PRETREATMENT
to the
DEVELOPMENT DOCUMENT
for the
SECONDARY COPPER SEGMENT
of the
NONFERROUS METALS MANUFACTURING
POINT SOURCE CATEGORY
Russell E. Train
Administrator
Andrew W. Breidentach, Ph.D.
Assistant Administrator for
Water and Hazardous Materials
Eckardt C. Eeck
Deputy Assistant Administrator for
Water Planning and Standards
Robert B. Schaffer
Director, Effluent Guidelines Division
Geoffrey H. Grubbs
Project Officer
January 1977
Effluent Guidelines Division
Office of Water and Hazardous Materials
U.S. Environmental Protection Agency
Washington, D.C. 20460
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ABSTRACT
This document represents the findings of an extensive study
of the secondary copper smelting industry by the
Environmental Protection Agency for the purpose of
developing pretreatment standards to implement section
307(b) of the Federal Water Pollution Control Act, as
amended.
This document is intended to supplement an earlier study of
the industry, "Development Document for Interim Final
Effluent Limitations Guidelines and Proposed New Source
Performance Standards for the Secondary Copper Subcategory
of the Copper Segment of the Nonferrous Metals Manufacturing
Point Source Category", published by EPA in February, 1975
(see Reference 1). This earlier study presented background
information used in the development of effluent guidelines
for sources discharging to navigable surface waters of the
U.S. Much of the information found in this earlier study is
also presented here, although it has been supplemented,
updated, and clarified as needed.
The pretreatment standards contained herein are based upon
the application of the best practicable pretreatment
technology. Section 307(b) of the Act requires sources
discharging to publicly owned treatment works (POTW) to
comply with these standards within three years from the date
of promulgation of the accompanying regulations.
The development of data and recommendations in this document
relate to waste water generated in metal cooling, slag
quenching and granulation, slag milling and classification,
furnace exhaust scrubbing, and electrolytic refining
operations of the secondary copper smelting industry.
Supporting data and rationale for development of the
pretreatment standards are also contained in this report.
As used in this document, "indirect discharger" or "POTW
discharger" refers to a plant which introduces its process
waste waters to a POTW. Similarly, a "direct discharger" is
a plant which discharges process waste waters to navigable
surface waters of the U.S., including those plants which may
be meeting a no discharge limitation.
111
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CONTENTS
Section page
I CONCLUSIONS 1
II RECOMMENDATIONS 3
Waste Water From Metal Cooling 3
Waste Water From Slag Quenching
and Granulation 4
Waste Water From Furnace-Exhaust
Scrubbing 4
Waste Water From Electrolytic-
Refining Operations 4
III INTRODUCTION 5
Purpose and Authority 5
Methods Used for Development
of Pretreatment Standards 8
General Definition of the
Secondary Copper Industry 9
General Technical Background 10
Process Description 12
Description of Secondary Copper
Industry Segment Discharging
to POTW 31
IV INDUSTRY CATEGORIZATION 37
Objectives of Categorization 37
Factors Considered 37
Industry Profile 39
Factors 45
V WASTE CHARACTERIZATION 53
Introduction 53
sources of Waste Water 53
Characteristics of Waste Water
Generated by Secondary copper
Industry 53
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CONTENTS (continued)
Section Page
VI SELECTION OF POLLUTANT PARAMETERS 81
Introduction 81
Rationale for Selection of
Pollutant Parameters 81
Rational for Rejection of Other
Waste Water Constituents as
Pollutant Parameters 86
VII CONTROL AND TREATMENT TECHNOLOGY 97
Introduction 97
Waste Water From Contact Cooling
of Molten Metal 98
Waste Water From Slag Quenching
and Granulation 105
Waste Water From Furnace
Exhaust Scrubbing 109
Waste Water From Electrolytic
Refining Operations 123
Combined Waste Water Streams 127
Treatment Technology for Oil
and Grease 130
VIII COSTS, ENERGY, AND NONWATER QUALITY
ASPECTS 135
Introduction 135
Basis for Cost Estimation 135
Costs of Control and
Treatment Alternatives 146
Non-Water Quality Aspects 153
vi
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CONTENTS (continued)
Section paqe
IX BEST PRACTICABLE PRETREATMENT TECHNOLOGY 231
Introduction 231
Industry Categorization and
Waste Water Streams 231
Pretreatment Standards 232
Identification of Best Practicable
Pretreatment Technology 233
Features of Best Practicable
Pretreatment Technology 235
Total Costs 237
X ACKNOWLEDGMENTS 239
XI REFERENCES 241
XII GLOSSARY 245
VII
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TABLES
Number Title Page
1 PROCESS OPERATION FREQUENCY 34
2 SIZES OF POTW 35
3 CHARACTERISTICS OF SECONDARY COPPER
SMELTERS AND REFINERS - POTW
DISCHARGERS 38
4 SECONDARY COPPER AND BRASS AND
BRONZE SMELTERS - DIRECT
DISCHARGERS 40
5 DISTRIBUTION OF AIR POLLUTION
CONTROL PROCESSES 46
6 WATER USAGE BY PRODUCT 47
7 WATER USAGE BY PROCESS 48
8 WASTE WATER DISPOSAL PRACTICES
(INDUSTRY-WIDE) 55
9 PROCESS WATER USE AND DISCHARGE
FLOW RATES 57
10 CHARACTERISTICS OF WASTE WATER FROM
EMISSIONS SCRUBBING - POTW
DISCHARGERS 60
11 CHARACTERISTICS OF RAW WASTEWATER
FROM EMISSIONS SCRUBBING -
POTW DISCHARGERS 61
12 CHARACTER OF WASTE WATER FROM AIR
SCRUBBER AFTER THICKENER -
DIRECT DISCHARGERS 62
13 CHARACTERISTICS OF RAW WASTEWATER FROM
METAL COOLING - DISCHARGES TO POTW 66
14 CHARACTERISTICS OF RAW WASTEWATER
FROM PHOSPHOR-COPPER SHOTTING -
POTW DISCHARGERS 67
IX
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TABLES (continued)
Number Title page
15 CHARACTERISTICS OF RAW WASTEWATER FROM
SHOT QUENCHING - POTW DISCHARGER
PLANT 3 68
16 CHARACTER OF WASTE WATER FROM MOLTEN
METAL COOLING AND QUENCHING -
DIRECT DISCHARGER 69
17 CHARACTERISTICS OF RAW WASTEWATER FROM
SLAG GRANULATION - POTW DISCHARGER
PLANT 11 71
18 CHARACTER OF WASTE WATER FROM SLAG
QUENCHING AND GRANULATION -
DIRECT DISCHARGERS 72
19 CHARACTERISTICS OF SPENT WASTE
ELECTROLYTE AFTER COPPER RECLAMATION
BY IRON CEMENTATION - PLANT 5 -
POTW DISCHARGER 74
20 CHARACTER OF WASTE WATER FROM NONCONTACT
COOLING, PLANT E - DIRECT DISCHARGER 76
21 CHARACTER OF WASTE WATER FROM
NON-CONTACT COOLING - DIRECT
DISCHARGER PLANT R, PIPE 009 77
22 CHARACTER OF WASTE WATER FROM
NON-CONTACT COOLING - DIRECT
DISCHARGER PLANT R, PIPE 010 78
23 CHARACTER OF WASTE WATER FROM
PLANT RUNOFF, PLANT V 79
24 EFFECTIVENESS OF THE TREATMENT
ALTERNATIVES FOR WASTE WATER FROM
MOLTEN METAL COOLING 104
25 PHOSPHOR COPPER FURNACE SCRUBWATER
BLEED PRETREATMENT WITH CAUSTIC,
SETTLING AND DISCHARGE TO POTW -
PLANT 11 115
26 SETTLING TREATMENT OF ANODE
FURNACE SCRUBWATER BLEED - PLANT 5 116
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TABLES (continued)
Number Title
27 BILLET FURNACE SCRUEWATER BLEED
SETTLING AND DISCHARGE TO POTW -
PLANT 5 117
28 EFFECTIVENESS OF TREATMENT ALTERNATIVES
FOR SECONDARY COPPER FURNACE EMISSIONS
SCRUBWATER 118
29 RESULTS OF SAMPLING WASTE WATER
FROM FURNACE EXHAUST SCRUBBING,
COMPANY E (DIRECT DISCHARGER) 119
30 RESULTS OF SAMPLING WASTE WATER
FROM FURNACE EXHAUST SCRUBBING,
MILLING, AND CLASSIFYING SLAGS,
COMPANY V (DIRECT DISCHARGER) 120
31 EFFECTIVENESS OF TREATMENT ALTERNATIVES
FOR WASTE WATER FROM WET SCRUBBING -
DIRECT DISCHARGERS 122
32 EFFECTIVENESS OF TREATMENT ALTERNATIVES
FOR WASTE WATER FROM ELECTROLYTIC
REFINING - INDIRECT S DIRECT DISCHARGERS 126
33 CHARACTERISTICS OF EFFLUENT FROM LIME
TREATMENT AND CLARIFICATION FACILITY -
COMBINED WASTE WATER STREAMS, PLANT R 131
34 EFFECTIVENESS OF LIME TREATMENT AND
CLARIFICATION FACILITY - COMBINED WASTE
WATER STREAMS, PLANT R 132
35-40 CONTROL COSTS: METAL COOLING
(NO CHARCOAL COVER) 155-160
41-46 TREATMENT COSTS: METAL COOLING
(NO CHARCOAL COVER) 161-166
47-54 CONTROL COSTS: METAL COOLING
(CHARCOAL COVER) 167-174
55-60 TREATMENT COSTS: METAL COOLING
(CHARCOAL COVER) 175-180
61-62 CONTROL COSTS: SHOT QUENCHING 181-182
XI
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TABLES (continued)
Number Title Paqe
63-64 TREATMENT COSTS: SHOT QUENCHING 183-184
65-66 CONTROL COSTS: PHOSPHOR SHOT QUENCHING 185-186
67~68 TREATMENT COSTS: PHOSPHOR SHOT QUENCHING 187-188
69-70 CONTROL COSTS: PHOSPHOR-COPPER EMISSIONS
SCRUBBING AND QUENCHING, PLANT 14 189-190
71-72 TREATMENT COSTS: PHOSPHOR SHOT QUENCHING,
PLANT 14 191-192
73-74 TREATMENT COSTS: PHOSPHOR SHOT QUENCHING,
PLANT 19 193-194
75-76 CONTROL COSTS: BILLET COOLING 195-196
77-78 TREATMENT COSTS: BILLET COOLING 197-198
79-80 CONTROL COSTS: ANODE COOLING 199-200
81-82 TREATMENT COSTS: ANODE COOLING 201-202
83-86 CONTROL COSTS: FURNACE EXHAUST
SCRUBWATER 203-206
87-88 CONTROL COSTS: PHOSPHOR COPPER
FURNACE EXHAUST SCRUBWATER 207-208
89-92 TREATMENT COSTS: FURNACE EXHAUST
SCRUBWATER 209-212
93-94 TREATMENT COSTS: PHOSPHOR COPPER
FURNACE EXHAUST SCRUBWATER 213-214
95-96 CONTROL COSTS: SLAG GRANULATION 215-216
97-98 TREATMENT COSTS: SLAG GRANULATION 217-218
99-102 CONTROL COSTS: ELECTROLYTE 219-222
103-106 TREATMENT COSTS: ELECTROLYTE 223-226
XII
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TABLES (continued)
Number Title Page
107 COST EFFECTIVENESS OF TREATMENT
AND CONTROL ALTERNATIVES 227
108 ESTIMATED ADDITIONAL TREATMENT AND
CONTROL NEEDS FOR SECONDARY COPPER
POTW DISCHARGERS 229
109 ESTIMATED COSTS OF ADDITIONAL
TREATMENT AND CONTROL TO SECONDARY
COPPER POTW DISCHARGERS 230
110 CONVERSION TABLES 252
xni
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FIGURES
Number Title page
1 RAW MATERIAL AND PRODUCT FLOW
DIAGRAM OF THE SECONDARY COPPER
INDUSTRY 14
2 PRODUCTION DISTRIBUTION, SECONDARY
COPPER SMELTING AND REFINING 33
3 COMPOSITE FLOW DIAGRAM OF WATER
SOURCES AND TREATMENT 54
4 TREATMENT AND CONTROL ALTERNATIVES
FOR WASTE WATER FROM CONTACT
METAL COOLING 100
5 CONTROL AND TREATMENT ALTERNATIVES
FOR WASTE WATER FROM SLAG QUENCHING
AND GRANULATION 107
6 CONTROL AND TREATMENT ALTERNATIVES
FOR FURNACE EXHAUST SCRUBWATER 113
7 CONTROL AND TREATMENT ALTERNATIVES
FOR WASTE WATER FROM ELECTROLYTIC
REFINING 124
8 END OF PIPE WASTE WATER
TREATMENT FACILITY 129
9 PUMP COSTS 138
10 PIPE COSTS 139
11 HOLDING AND MIXING TANK COSTS 140
12 COOLING TOWER COSTS 141
xv
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SECTION I
CONCLUSIONS
Secondary copper smelting is a single subcategory for the
purpose of establishing pretreatment standards. The
consideration of factors such as age and size of plant,
processes employed, geographic location, wastes generated,
and waste water treatment and control techniques employed
supports the categorization of this industry as a single
subcategory. The similarities of the wastes produced by the
secondary alloyed and unalloyed copper smelting operations
and the control and treatment techniques used to reduce the
discharge of pollutants further substantiates the treatment
of secondary copper smelting as a single subcategory. The
pretreatment levels identified for specific facilities take
into consideration the size of the secondary copper smelting
facility, as well as the mix of different recovery processes
possible within a single plant.
One conclusion is that certain metal constituents generated
by this industry can pass through or interfere with the
operation of publicly owned treatment works. It was found
that process waste water discharges from metal cooling,
emissions scrubbing, slag granulation and electrolytic
refining operations can be completely eliminated by the use
of recycle and reuse practices. Such practices are
frequently found in the industry, and the best practicable
control technology available for those secondary smelters
discharging directly to surface waters is identified as no
discharge of process waste waters (see 40 CFR 421.62). It
was also found that pH adjustment and settling of process
waste waters will protect POTW from interference by waste
stream constituents generated by the secondary copper
smelting industry, and would minimize the passing of these
constituents through POTW to the receiving waters.
It is estimated in this report that a capital cost of
$1,060,800 and an annual cost of $506,610 will be incurred
in order to install pH adjustment and settle facilities
necessary to comply with best practicable pretreatment
control levels. Alternatively, it is estimated that a
capital cost of $1,351,300 and an annual cost of $612,960 is
necessary for all such plants to recycle all process waste
waters, thus eliminating the introduction of pollutants to
POTW.
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SECTION II
RECOMMENDATIONS
In the secondary copper industry, waste water is generated
principally from four operations: cooling of molten
unalloyed or alloyed copper, slag quenching and granulation,
furnace exhaust scrubbing, and electrolytic refining. A
fifth operation, slag milling and classification, generates
a process waste water stream at some secondary copper
smelters, but this operation is not found at any of those
plants that introduce pollutants to PCTW. Each of these
streams is an integral part of the total water usage at a
given plant, although each operation may not be performed at
every plant. Water is consumed in these operations by
evaporation and by removal of sludges.
Best Practicable Pretreatment Technology
It was found that process waste water from contact metal
cooling, slag granulation, furnace exhaust scrubbing, and
electrolytic refining operations can be completely recycled
or reused to eliminate discharge. The application of this
recycle technology is recommended whenever such technology
is consistent with the aims and goals of the local POTW
operating authority. In cases where the introduction of
process waste waters from secondary copper smelters to a
POTW is to be made, the following standards apply:
Pretreatment Standard
Effluent Maximum for Average of daily
Characteristic any 1 day values for 30
consecutive days
shall not exceed
Copper, mg/1
Cadmium, mg/1
Oil and Grease,
mcr/1
1.0
0.40
100
0.50
0.20
—
Waste Water from Metal Cooling
The best practicable pretreatment technology for waste water
from contact metal cooling and quenching operations is
adjusting the pH, if necessary, to between 8 and 10 and
settling. This technology can be applied to the individual
stream or it may be applied as part of the combined process
waste water treatment. Periodic removal, dewatering, and
disposal of sludge from settling basins or tanks will be
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necessary. if charcoal cover is used, sludge removal
requirements will be significantly increased.
Waste Water from Slag Quenching and Granulation
The best practicable pretreatment technology for waste water
from slag quenching and granulation is settling the stream
to reduce suspended solids. pH should be adjusted, if
necessary, to between 8 and 10 before solids removal. This
technology can be applied to the specific stream or as part
of the combined process waste water treatment before reuse
or recycle.
An alternative control method applicable to waste water from
the quenching of slag is to air cool the molten slag in pots
and employ mechanical size reduction for handling and
subsequent recovery of the contained metal content.
Waste Water from Furnace Exhaust Scrubbing
The best practicable pretreatment technology for waste water
from furnace exhaust scrubbing is pH adjustment, if
necessary, to between 8 and 10 followed by settling to
remove solids. This technology is usually applied to the
specific stream and kept separate from the combined process
waste water, although this may be accomplished as part of
combined process waste water treatment.
Waste Water from Electrolytic Refining Operations
The best practicable pretreatment technology for waste water
from electrolytic refining is the removal of copper by
cementation with iron metal, followed by lime neutralization
to a pH between 8 and 10 and settling of the waste stream to
remove solids.
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SECTION III
INTRODUCTION
Purpose and Authority
The Environmental Protection Agency (EPA or Agency) is
required to establish pretreatment standards for existing
sources pursuant to section 307 (fc) of the Federal Water
Pollution Control Act, as amended (33 U.S.C. 1317(b) and
(c), 86 Stat. 816 et seq; P.L. 92-500) (the Act). HO CFR 128
establishes general provisions dealing with pretreatment
standards for existing sources introducing pollutants into a
publicly owned treatment works (POTW) which sources would be
an existing source subject to section 301 of the Act if they
were to discharge pollutants directly to navigable waters of
the United States.
(a) Legal Authority
Section 307(b) of the Act requires the Administrator to
promulgate regulations establishing pretreatment standards
for the introduction of pollutants into treatment works
which are publicly owned for those pollutants which are
determined not to be susceptible to treatment by such
treatment works, or which would interfere with the operation
of such treatment works. Pretreatment standards established
under this section shall prevent the discharge of any
pollutant through treatment works which are publicly owned
where the pollutant interferes with, passes through, or is
otherwise incompatible with such works.
(b) Purpose of the Regulations
Subsequent to the promulgation of pretreatment standards (40
CFR 128) on November 8, 1973, the Agency has proposed and
promulgated numerous pretreatment standards relative to
specific industry category waste water discharges for both
existing sources and new sources.
(c) Statutory Considerations
The Act was designed by Congress to achieve an important
objective — "restore and maintain the chemical, physical,
and biological integrity of the Nation's waters." Primary
emphasis for attainment of this goal is placed upon
technology based regulations. Industrial point sources
which discharge into navigable waters must achieve
limitations based on Best Practicable Control Technology
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Currently Available (BPT) by July 1, 1977 and Best Available
Technology Economically Achievable (BAT) by July 1, 1983 in
accordance with sections 301(b) and 304(b). New sources
must comply with New Source Performance Standards (NSPS)
based on Best Available Demonstrated Control Technology
(BDT) under section 306. Publicly owned treatment works
(POTW) must meet "secondary treatment" by 1977 and best
practicable waste treatment technology by 1983 in accordance
with section 301 (b) and 201 (g) (2) (A).
Users of a POTW also fall within the statutory scheme as set
out in section 301 (b). Such sources must comply with
pretreatment standards promulgated pursuant to section
307 (b) .
Section 307(b) is the key section of the Act in terms of
pretreatment for existing sources. It provides that the
basic purpose of pretreatment is "to prevent the discharge
of any pollutant through treatment works...which are
publicly owned, which pollutant interferes with, passes
through, or otherwise is incompatible with such works." The
intent is to require treatment prior to introduction of the
pollutant to the POTW which is complementary to the
treatment performed by the POTW. Duplication of treatment
is not the goal; as stated in the Conference Report (H.R.
Rept. No. 92-1465, page 130) "In no event is it intended
that pretreatment facilities be required for compatible
wastes as a substitute for adequate municipal waste
treatment works." On the other hand, pretreatment by the
industrial user of a POTW of pollutants which are not
susceptible to treatment in a POTW is absolutely critical to
attainment of the overall objective of the Act, both by
protecting the POTW from process upset or other
interference, and by preventing discharge of pollutants
which would pass through or otherwise be incompatible with
such works. Thus, the mere fact that an industrial source
utilizes a publicly owned treatment works does not relieve
it of substantial obligations under the Act. The purpose of
this regulation is to establish appropriate standards for
the secondary copper industry.
Toxic pollutants are not considered. The relationship of
any toxic pollutant limitations established under section
307 (a) to users of a POTW or to the POTW itself will be
established under separate regulations.
In determining numerical pretreatment standards the initial
step was to classify the pollutants discharged by a source
to a POTW in terms of the statutory criteria of
interference, pass-through, or other incompatible effect.
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These pollutants will fall, generally, into three classes.
The first class is composed of those pollutants which are
similar, in all material respects, to the pollutants which
are found in municipal sewage and which the typical POTW is
designed to treat. For such pollutants, no pretreatment
would be required and the numerical standard will be "no
limitation." The second class of pollutants are those which,
in large quantities, would interfere with the operation of a
POTW but which are adequately treated by the POTW when
received in limited quantities. Such pollutants will be
subject to pretreatment standards designed to allow their
release into the POTW in treatable amounts. Finally, the
third class of pollutants are those which are of a nature
that requires the maximum feasible pretreatment in order to
prevent interference with the POTW or pass through of the
pollutant or other incompatibility. Such pollutants will be
subject to pretreatment standards based upon the practical
limits of technology.
(d) Technical Basis for Pretreatment Standards
The Act requires that pretreatment standards for both new
sources and existing sources be promulgated to prevent the
introduction of any pollutant into a POTW which would
interfere with the operation of such works or pass through
or otherwise be incompatible with such works. Such
standards would allow the maximum utilization of a POTW for
the treatment of industrial pollutants while preventing the
misuse of such works as a pass-through device. The
standards also protect the aquatic environment from
discharges of inadequately treated or otherwise undesirable
materials.
The primary technical strategy for establishing pretreatment
standards consists of the following provisions: (1)
pretreatment standards should allow materials to be
discharged into a POTW when such materials are similar, in
all material respects, to municipal sewage which a "normal
type" POTW is designed to treat; (2) pretreatment standards
should prevent the discharge of materials of such nature and
quantity, including slug discharges, that would mechanically
or hydraulically impede the proper functioning of a POTW;
(3) pretreatment standards should limit the discharge of
materials which, when released in substantial concentrations
or amounts, reduce the biological effectiveness of the POTW
or achievement of the POTW design performance, but which are
treated when released in small or manageable amounts; and
(4) the pretreatment standards should require the removal,
to the limits dictated by technology, of other materials
which would pass through — untreated or inadequately
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treated — or otherwise be incompatible with a normal type
POTW.
Methods Used for Development of
Pretreatment Standards
This document is based in part upon an earlier study of the
industry, "Development Document for Interim Final Effluent
Limitations Guidelines and Proposed New Source Performance
Standards for the Secondary copper Subcategory of the Copper
Segment of the Nonferrous Metals Manufacturing Point Source
Category", published by EPA in February, 1975 (see Reference
1). This earlier study presented background information
used in the development of effluent guidelines for sources
discharging to navigable surface waters of the U.S. This
information has been updated and revised where necessary.
The pretreatment technology herein was developed in the
following manner. That portion of the secondary copper
industry which discharges to publicly owned treatment works
(POTW) was considered by identifying any potential basis for
subcategorizing the industry into groups. The purpose of
this was to determine whether separate limitations and
standards would be appropriate for the different
subcategories. Such possible categorization was considered
on the basis of water usage, raw materials processed,
products produced, manufacturing, plant age and size, and
other factors. The raw waste characteristics of the waste
waters produced were identified. This identification
included analyses of (1) the source and volume of water used
in the process employed and the sources of waste water and
their points of discharge, and (2) the constituents of waste
waters from operations which are not susceptible to
treatment by a POTW or which would interfere with the
operation of a POTW. The constituents of waste water which
should be subject to pretreatment standards were then
identified. Control and treatment technologies applicable
to each type of waste water produced were identified and
these included both inplant and end-of-process technologies.
The effluent levels resulting from the application of each
treatment and control technology, as well as the
limitations, reliability, and problems derived from and
associated with these technologies, were also identified.
The effects of the application of technologies upon other
pollution problems including air, solid waste, and noise
were identified, to establish nonwater environmental
impacts. Energy requirements were identified and the costs
of the application of the technologies were tentatively
assessed.
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This information, as outlined above, was evaluated to
determine a level of technology generally analogous to the
best practicable control technology currently available. In
identifying such technology, the following factors were
considered: the total cost of the application of the
technology in relation to the effluent reduction benefits to
be achieved from such application, the processes employed,
the engineering aspects of the application of control
techniques proposed through process changes, nonwater
quality environmental impact, and other factors.
Information sources utilized in this study included
published literature (references appear in Section XI),
trade literature, and all of the data collected in the
development of effluent limitations guidelines and standards
for the secondary copper smelting industry (Federal
Register, February 27, 1975 at page 8614 and accompanying
development document EPA 440/1-75/032-c, published February,
1975). Representatives of forty-six facilities of the
secondary copper industry were contacted, of which seventeen
were subsequently determined to discharge process waste
water to POTW. Representatives of seven facilities were
interviewed during plant visits (Plants 3, 5, 11, 14, 18 and
19 listed in Table 3 herein, and Plant C listed in Table 4) .
Analytical verification of effluent data from six facilities
(Plants 3, 5, 11, 14, 18 and 19) was made to determine the
loadings of various inplant and end-of-plant waste water
sources.
General Definition of the Secondary Copper Industry
The pretreatment standards recommended herein are applicable
to discharges resulting from the recovery, processing, and
remelting of new and used copper scrap and residues -co
produce copper metal and copper alloys. This definition,
which is established in 40 CFR 421.60, is intended to
include establishments melting and refining copper alloys
from secondary brass and secondary bronze scrap sources to
produce alloyed copper, as well as those melting and
refining copper-bearing scrap to recover principally pure
copper (unalloyed copper). The presmelting treatments,
melting and smelting operations, and refining operations
(except electrolytic refining) are common to both bronze and
brass and unalloyed copper production operations. Water
uses are similar and the pollutants contributed by both
operations to the waste water are also similar in origin.
The industry, by this definition, does not include the
collection, preliminary grading and preparation of scrap,
the production of brass or bronze ingots from essentially
virgin materials, or the recycling of copper-base materials
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by the fabrication industry. The definition is not intended
to include the scrap processed by plants that were primarily
designed to process primary copper ores or concentrates, nor
is it intended to include foundries that do not perform
refining operations.
General Technical Background
To convert copper-bearing scrap and residues from melting
operations into salable secondary brass and bronze ingots or
copper products, alloying additions and impurities must be
either adjusted to specifications or reduced to specified
levels, respectively. To accomplish this, the secondary
copper industry uses some recovery and refining process
steps identical to those of primary copper plants, as well
as its own unique processes.
Scrap is identified and segregated, often by hand sorting,
according to accepted standard classifications. Segregated
scrap metal and waste materials from melting operations
(slags and residues) usually require some preliminary
processing to remove both valuable and deleterious
associated constituents (presmelting treatment).
The common methods used for producing secondary metal are
melting, smelting, and alloying. Operating techniques
usually differ from primary metal operations because of the
difference in physical and chemical properties of the
respective raw materials.
The technology of the secondary copper industry has been
well reviewed in the literature. The technology described
is general for the entire industry and does not imply that
each operation is used by all of the establishments. in
fact, variations in the technology employed by the
individual companies are considered by them to provide the
competitive edge that keeps them in business. Hence, much
of the detailed processing information is considered
proprietary. Overall, the recovery efficiencies of all
processes are reasonably high and the quality of the
products meets rigid specifications.
The term "secondary metal" as used in this document and in
the industry pertains only to the origin of the metal and
not its quality. Secondary metal is produced from scrap
metal or metallurgical wastes as contrasted with primary
metal, which is produced from ores. Secondary metal is re-
refined metal returned to the industry after having been
used and is equal in quality to metals made from primary
sources.
10
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Secondary copper loses its identity, except statistically,
as it is processed. It is not possible to determine whether
a copper wire bar was derived from scrap charged to a
converter, or whether a brass ingot is made from brass scrap
or virgin metals. In the utilization of segregated scrap
there are, however, selected points of entry of the scrap
into secondary metal production, which are set by the
quality of the scrap with respect to its copper content.
Generally, clean scrap consisting of pure copper, such as
copper wire, will enter the recovery process at a point
relatively late in the metal refining process, where pure
copper is produced. If the quality of the scrap (with
respect to copper content) is intermediate due to alloying
constituents, it must enter the refining process at an
earlier stage, so that these impurities can be removed
before a purified copper can be produced. Still lower
grades of raw material must enter the metal refining process
at the earliest steps of metal recovery such as blast
furnace or cupola operations. Progressively, through a
series of stepwise pyrometallurgical operations, such
material can end up as pure copper.
The manufacture of secondary brass and bronze ingots from
scrap and residues usually stops short of the extensive re-
fining necessary to recover pure copper from lower grade
copper-bearing scrap or residues. Some refining is prac-
ticed in brass and bronze production operations but can be
minimized with the use of selectively sorted scrap or
residues. Adjustment of the alloy composition can be done
by dilution and alloying, as well as by refining.
Therefore, the secondary brass and bronze smelters will use
some high grade (pure) copper scrap for dilution purposes
and will compete for its purchase with smelters of pure
copper. Conversely, secondary copper smelters will purchase
intermediate grade scrap for its copper value and remove the
alloying metals by fire refining.
The early operations in the recovery of refined secondary
copper from copper-bearing scrap and residues, and the
recovery of brass and bronze from the same type of scrap and
residues, are very nearly identical. Operations become
different in the extent of refining necessary to produce
refined copper as opposed to specification bronze and brass
alloys. However, the chemistry for refining brass and
bronze and the pyrometallurgy necessary to produce partially
refined copper are very similar. These and other
similarities, as well as the differences in the production
of the two types of products with respect to waste water
generation, are covered in the following sections.
Electrolytic refining is used only for the refining of
11
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copper. However, this type of refining will be treated as
part of the overall secondary copper industry, since
melting, refining, and casting operations follow the
electrolytic refining step in the production of refined
copper by some of the companies studied.
In summary, a generalization can be made that the ingot
makers (brass and bronze) try to utilize all the elements
present in their scrap to produce an alloy; copper refiners
are primarily interested in the recovery of the copper
content, plus perhaps zinc and precious metals as byproducts
(if present in sufficient amounts). Both the ingot maker
and the copper refiner will treat low grade, copper-bearing
waste materials (residues) to recover the contained metal
values.
Process Description
The recovery of copper or copper-base alloys from copper
bearing scrap metal and residues involves four broad
operations:
(1) Collecting, sorting, and transporting
raw materials;
(2) Presmelting preparation;
(3) Charging, melting, and refining;
(4) Pouring or casting the product line.
Collection, preliminary sorting, and transporting are not
considered to be functions of the secondary copper industry
as herein defined, but rather that of the scrap dealers.
Operations (2) through (4) above vary throughout the
industry, resulting in variations in the amount of water
used and waste water generated.
The presmelting treatments of the raw materials (solids and
residues) and the melting and smelting operations (which
include refining steps) are common to the production of both
brass and bronze ingots and for refined copper. Water uses
and waste water generation are similar in both types of
production. The cooling of molten metal after pouring
ingots or anodes is common for brass and bronze and for
refined copper.
Typically, the production of refined copper requires
additional refining steps to remove impurities to specified
levels. Further purification is done by additional smelting
operations (fire-refined copper), or by electrolysis
(electrolytic refined or cathode copper) , or by both. To
produce relatively pure cathode copper, cast anodes must be
12
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electrolytically refined. The refined copper cathodes are
melted, deoxidized, if necessary, and cast into copper
billets or cakes. Copper, suitable for fabrication into
pipe or tubing, is also made by smelting and fire refining
high quality copper scrap and casting it into suitable
billets.
A few plants produce copper shot, which may or may not be
alloyed with phosphorus. Shot is manufactured by directing
a stream of high-purity molten copper into a quench pit. In
some plants, the shot is first fragmented as it is poured
with a flat vessel with appropriately spaced holes. The
shot is then retrieved from the pit, drained, dried, and
sized for sale as an alloying agent.
A generalized flow sheet for the various operations in the
production of brass and bronze ingots or refined copper is
presented in Figure 1.
Each of the operations involved in secondary copper and
brass and bronze production is described in detail in the
paragraphs that follow. Raw materials and the various
presmelting operations are discussed first, followed by a
detailed description of the processes for smelting low grade
scrap and residues. The processes for smelting intermediate
and high grade scrap (which are different from those used in
processing low grade scrap) are then discussed, followed by
the processes used in pouring and casting the final product.
Raw Materials
Obsolete consumer items, industrial copper-bearing scrap
metal (solids) and melting wastes (slags and residues) are
the basic raw materials of the secondary copper industry.
About two- thirds of the recycled copper tonnage is in the
form of brass and bronze, with the remaining one-third in
the form of copper. Additional copper values are recovered
from copper-bearing wastes, such as skimmings, grindings,
ashes, irony brass and copper residues and slags. The
United States Department of Interior has estimated that 60
percent of all copper-base metal is reclaimed as old metal
and comes back into production again. The cycle between its
original use and recovery is approximately 40 years.
The segregation and classification of scrap metal are
important steps in the production of alloyed ingots or pure
copper. Segregation of copper-base scrap is done in a
preliminary way by the scrap dealer (old scrap) or by the
fabrication plant as the scrap is generated (new scrap).
The copper- bearing scrap sold to the smelters contains
13
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I I oj i K.MII SI:K.M'
(T)R>-flnery Hra»«
Scrap (Star',a c> '
Depleted Slid
(Sell or Landfill)
BLAST OR COUPOLA
MELTINV FURNACE
INTERMEDIATE v'KADE SCRAP
(3)Tc-al - 37 Classifications, eg.
Composition Oi Red Brass
Railroad Car Journals
Yellow Brass
Cartridge Cases
Auto Radiators
Bronzes (Aluminum, Manganese,etc)
Sludges to Prcc.
Met. Ri'cov, Lou
Oracle- Sc rap or
I
C'y
Hl"ll CRAl.C Sr'AT
0 1 Ko. 1 Toppi-r Wir-'
Iso 1 heavy Copter
(y -f.'lo. 2 Copp. r k'lre
L'-o. 2 Heavy Copper
© l.lfht Copper
R. slJni-R to Low Grade Scrap
Figure 1. Raw material and product flew aia<-rram
of the secondary cr>|.>per indastry.
14
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metallic and nonmetallic impurities. Included among these
are lead, zinc, tin, antimony, iron, manganese, nickel,
chromium, precious metals, and undesirable organic-base
constituents, such as insulation (plastic and other types),
oil, grease, paint, rubber, and antifreeze. Some scrap
dealers prepare the scrap by removing the undesirable
nonmetallic materials and compacting the scrap metal into
bundles. Additional sorting and presmelter treatment of the
raw material are often done by the smelter. Some smelters
do most of the pretreatment steps themselves. Often,
smelters perform recovery of metal value from scrap or
residues on a toll basis for specific customers. In such
cases, the origin of the scrap fixes its composition and
little, if any, segregation or presmelter treatment is
required before smelting.
No water is used in the segregation and sorting of scrap.
Presmeltinq Treatment
Before scrap, in the forms of sclids (metal) and residues,
is used by the smelter, some type of pretreatment is per-
formed. Additional sorting is often done by the smelter to
attain tighter control of the alloy constituents and the
copper content. In addition, metallic and nonmetallic
contaminants are removed before the scrap is compacted for
easy handling. The type of presmelting treatments used will
depend on the type of scrap being processed. These are
discussed in detail below.
Stripping Process. Insulation and lead sheathing are re-
moved from electrical conductors, such as cables, by
specially designed stripping machines or by hand.
Essentially no atmospheric emissions or liquid wastes are
generated by this process. However, significant quantities
of solid wastes are produced. These wastes consist
primarily of organic materials, such as plastics, paper, and
other materials used as protective coverings on copper
scrap. The lead is sold, reclaimed, or used in producing
copper-base alloys. The organic solid wastes are reclaimed
or disposed of by burning or landfill.
Briguetting Process. Compressing bulky scrap, such as
borings, turnings, tubing, thin plate, wire screen, and
wire, into small bales densities the scrap, permits more
compact storage, and makes for easier handling and faster
melting. The problem of oxidation of the metal is also
diminished. Briquetting is carried out by compacting the
scrap with hydraulic presses.
15
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Essentially no atmospheric emissions, liquid wastes, or
solid wastes are generated during this process.
Size Reduction Process. Large thin pieces of scrap metal
are reduced in size by pneumatic cutters, electric shears,
and manual shearing. Tramp iron liberated from the scrap is
removed from the shredded product magnetically. The iron-
free products are usually briquetted for easy handling.
Shredding is also employed in the separation of insulation
on copper wire. The insulation is broken loose from metal
by shearing action and removed from the metal by air
classification.
When treating bulky metal items, the process produces small
quantities of atmospheric emissions, consisting of dusts of
approximately the same composition as the metal, collection
of the dust via cyclones or baghouses permits recovery of
the metal value. When insulation is present, the
nonmetallic portion is separated from the metallic fraction.
The metal fraction is recovered, while the insulation is
either reclaimed or becomes a solid waste that is
incinerated or disposed of in a landfill. Water is used in
the shredding operation for equipment cooling.
Crushing Process. Previously dried, brittle, spongy turn-
ings, borings, and long chips are processed in hammermills
or ballmills. After crushing, tramp iron is removed mag-
netically. Dust particles consist of dirt, organic com-
pounds, finely divided metal, and undefined solid wastes.
Such areas may or may not be hooded with dust recovery
provisions. Water use in the crushing operation is limited
to occasional equipment cooling.
Drying Process. Borings, turnings, and chips from machining
are covered with cutting fluids, oils, and greases. These
contaminants are removed in the drying process, where the
scrap is heated in, for example, a rotary kiln to vaporize
and burn the contaminants. It should be noted that "drying"
as used by the secondary copper industry does not carry the
same meaning as it does in chemical industries, where the
term applies only to the removal of water.
Drying results in the evolution of considerable quantities
of hydrocarbons, depending on the amount present in the
scrap. The oils, greases, and cutting fluids contain
sulfinated and chlorinated hydrocarbons. Therefore, the
gaseous emissions are composed of sulfur oxides, hydrogen
chloride, hydrocarbons, and other combustion products.
Particulate matter in the atmospheric emissions is soot and,
16
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possibly, metallic fumes. Essentially no solid or liquid
wastes are generated by the process.
The atmospheric emissions are controlled by burning the
vaporized fumes in afterburners, which oxidize the
hydrocarbons to carbon dioxide and water. Inorganic
particulates settle out in the afterburner section. Wet
scrubbing may be employed to further remove these gases from
the exhaust. Sulfur oxides and chlorides emissions are
usually uncontrolled.
Burning Process. Much of the scrap is covered with paper
and organic polymer insulation, such as rubber,
polyethylene, polypropylene, or polyvinyl chloride. The
contaminants, not removed by stripping, are removed from the
scrap by the burning process using furnaces, such as rotary
kilns.
The burning process is a potential source of air pollution
problems, because of the organic contaminants in the scrap.
In addition to the combustion products such as carbon
dioxide and water, the emissions may contain such gases as
phthalic anhydride and hydrogen chloride from the burning of
polyvinyl chloride. Fluorocarbon insulation releases
hydrogen fluoride when burned. Many of these gases are
highly toxic and corrosive. Water may be used in wet
scrubbers to remove these emissions.
Sweating Process. Scrap containing low melting point
materials, such as radiators, journal bearings, and lead
sheathed cables, can be sweated to remove babitt, lead, and
solder as valuable byproducts, which would otherwise con-
taminate a melt. Scrap may be added directly to a melt
without sweating if the melt requires substantial amounts of
the sweatable constituents. Sweating is done by heating in
an oil or a gas fired muffle type furnace with a sloped
hearth, so that the charge can be kept on the high side and
away from the fluid low melting components. The molten
metal is collected in pots, and the sweated scrap is raked
until most of the low melting metals have been freed. The
process can be a continuous or a batch operation. Sweating
is also done in pots by dumping the scrap into molten alloy,
which absorbs the sweated babbit, lead, or solder. Rotary
kilns have been used on small size scrap. The tumbling
action aids in removing the molten metals. For items which
are difficult to sweat, a reverberatory furnace equipped
with a shaking grate is used. Continuous sweating is done
in tunnel furnaces that have provisions for solder, lead,
and babbit recovery.
17
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Atmospheric emissions consist of variable quantities of
fumes and combustion products originating from antifreeze
residues, soldering fluxes, rubber hose remains, and the
fuel used to heat the sweat furnace. Wet scrubbers are used
by some smelters to control these emissions. No other water
is used in sweating operations.
Residue Concentration Processes. Some of the smaller
smelters in the industry concentrate the copper values in
slags and other residues, such as drosses, skimmings,
spills, and sweepings, before charging the concentrates into
rotary or reverberatory furnaces. Slags may be crushed,
screened through a coarse screen to remove trash and lumps
of copper, pulverized with a ball mill, and concentrated on
a table classifer. The concentrate usually contains 70 to
90 percent copper or copper alloy, and the gangue, or
depleted slag, contains four or five percent copper alloy.
The depleted slag is usually retained at the plant site as
landfill. One direct discharger charges residues containing
about 30 percent copper or greater directly into their
rotary furnace. Lower grade residues are wet milled and
concentrated by gravity and table classifiers.
The concentration of residues by wet grinding and
classifying requires large volumes of water. The water
contains some milling fines as suspended solids and
dissolved solids from the soluble components of the residue
and metals. To limit water consumption, the water used for
milling is recycled from holding tanks or ponds. Although
this process is practiced by the industry, no smelters which
discharge to POTW were identified which perform wet milling
and classification of residues or slags.
Residue Pelletizing and Roll Briquettinq. Most small brass
and bronze ingot makers do not process residues, but
actually sell their copper bearing residues to the larger
refineries for processing to recover the copper values.
Some of the large refineries charge the residues into their
cupola or blast furnaces for the recovery of the copper
content in the slag or residues. The fine slags or residues
must be agglomerated before charging to prevent them from
being blown out of the stacks. The fine portions of the
copper rich slags or other residues are pelletized by adding
water and some binder, if necessary, and rolling the
material in a disk or drum pelletizer until most of the
fines are in the form of small marble size pellets. A few
plants are evaluating roll briquetting equipment to produce
small pillow shaped briquettes of the fine slag or residue.
The fine material is mixed with a small amount of resin
binder and some water before it is briquetted.
18
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Although small amounts of water are used in the process,
waste water is not generated in this operation.
Blast Furnace or Cupola Process. These operations were not
considered to be part of the presmelting treatment. They
are, however, discussed in detail below in the section on
smelting processes.
Summary of Water Uses in Scrap Preparation. The literature
indicates that water is used occasionally in hammer mills,
in insulation stripping operations, and in wet milling
operations to concentrate copper from copper slags. In the
smelters studied, water was found to be used only in wet
milling operations.
Water is also reported in the literature to be used in
systems employing leaching to recover copper from low grade
residues or slags or in air cleaning systems for the
incinerators or sweating furnaces, if these systems employed
water in any gas cleaning process. None of the plants
studied reported water use for these purposes.
Smelting Low Grade Scrap and Residues
Drosses, slags, skimmings, and low grade copper and brass
scrap (those badly mixed or containing high levels of
impurities) are processed in blast furnaces or cupola
furnaces. These low grade, copper bearing materials are
melted to separate the copper values from slags or residues
and to produce molten metal that can be processed further
immediately after recovery, or after being cast into ingots
or shot for later use or sale.
The product of cupola or blast furnace melting (black copper
or cupola melt) generally is a mixture of copper and
variable amounts of most of the common alloying elements
such as tin, lead, zinc, nickel, iron, phosphorus, and
sometimes arsenic, antimony, aluminum, beryllium, chromium,
manganese, silicon, precious metals, or other elements. A
matte is also formed when sufficient sulfur is present to
form a complex copper-iron-nickel-lead sulfide. Similar
mixtures may be obtained with other melting furnaces when
the scrap charge materials are not segregated.
Under 1960 market conditions, the minimum profitable copper
content for the charge was about 30 percent. In 1973, the
market conditions made it profitable to charge with as low
as 10 percent copper content material. The charge may be in
the form of irony brass and copper, fine insulated wire,
motor armatures, foundry sweepings, slags, drosses, and many
19
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other low grade materials. Fine materials are pretreated by
pelletizing, briquetting, or sintering to reduce losses in
the stack gas. Limestone and millscale are added as fluxes
to produce iron silicate slags (depleted slag). Low sulfur
coke is used in cupolas or blast furnaces to reduce matte
(copper sulfide) formation.
During the cupola and blast furnace processes, metallic
constituents (copper alloys and copper) melt, while the
limestone and iron (and aluminum, silicon, etc.) oxides fuse
in the smelting zone and form a molten slag, which mixes
with the metals. The copper compounds are reduced by the
coke. The molten materials flow downward through the coke
bed and are collected in a crucible below. After a period
of quiescence, the metal and slag form separate layers and
are tapped.
A typical slag from a blast furnace has the following
approximate composition:
Feo
Cao
Si02
Zn
Cu
Sn
Collected dusts contained:
Percent
29
19
39
10
0.8
0.7
Zn
Pb
Sn
Cu
Sb
Cl
Percent
58-61
2-8
5-15
0.5
0.1
0.1 - .5
The product metal composition, as well as the materials in
the slag and dusts, will vary with the materials charged.
Blast Furnace. The blast furnace is a vertical shaft
furnace with a sealed top. This furnace is used to reduce
copper compounds, as well as to melt metal and form black
copper or a copper matte and a slag. Charges of copper
alloys, compounds, residues, and slags are fed into the top
of the furnace through a double bell, gas seal arrangement,
along with coke for fuel, and fluxes. The top gases may be
cleaned and burned as a source of fuel (e.g., to preheat the
blast) . The blast air is blown in through tuyeres near the
20
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bottom of the shaft. Either molten metal or matte and slag
are tapped intermittently. Water use in the operation is
discussed in the section on cupolas.
Cupola Furnaces. Cupola furnaces are similar to blast
furnaces in design. Both furnaces are refractory lined,
vertical shaft furnaces charged from the top with coke,
scrap metal, copper rich slag, and flux, and fired with an
air blast that is blown in through tuyeres near the bottom
of the shaft. The cupola may be tapped continuously or
intermittently for metal and slag. Normally, cupolas are
used only to melt metal and slag; whereas, blast furnaces
are used to reduce copper bearing oxides or other residue
compounds. Cupolas normally use less fuel (coke) and a
lower temperature blast than do blast furnaces. The exhaust
gases from the cupola do not contain enough calorific value
to be utilized as a fuel.
The tuyeres and lower shell portion of both blast furnaces
and cupolas are normally water cooled. Large volumes of
water are required for cooling the walls and tuyeres. The
water normally is recirculated. The water pollutants are
mainly thermal and salts in cooling tower blowdown. The air
emissions from blast furnaces and cupolas are contaminated
and must be cleaned either with baghouse filters or high
energy water scrubbers to meet regional air quality
standards. If water scrubbers are used, then the waste
water must be treated before it can be recirculated or
discharged. At some plants, large volumes of water are used
to quench and granulate copper-poor (depleted) slags from
the smelting operation. This creates waste water that
requires treatment prior to discharge.
Converters. The process of conversion in the secondary
copper industry can be done in furnaces called converters,
which are specifically designed for that operation, or in
other types of furnaces in which molten metal is contained.
The operation is derived from primary copper operation in
which the sulfide matte is converted to an oxide-rich copper
melt by oxidation with air or oxygen-enriched air. In
secondary copper operations, however, only small amounts of
sulfide are present in the black copper, but it is heavily
contaminated with alloy metals, such as zinc, lead, nickel,
iron, manganese, aluminum, tin, antimony, silicon, silver,
or other metals and nonmetals contained in the scrap or
residues. since the sulfur content is low in secondary
black copper, fuel is required for converting operations;
whereas, the high sulfur content in primary copper serves as
the fuel.
21
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With the use of converters or converter-oriented operations,
the copper value in badly mixed alloys is reclaimed by
oxidizing most of the alloying elements and removing the
oxides as a slag. Molten metal is occasionally oxidized in
a converter by blowing air through ports in the bottom of
the furnace until most of the oxidizable alloying elements
and some of the copper are oxidized (blister copper). More
commonly, the molten metal in reverberatory or rotary
furnaces is oxidized by inserting water cooled lances into
the bath and blowing the bath with air or oxygen under a
silicate slag cover until the alloy impurities are reduced
to the desired level. The slag containing the alloy metal
oxides and some copper is removed, and the oxygen in the
remaining copper is reduced with charcoal and green wood
inserted in the bath. Depending on the extent of reduction,
various grades of refined copper are produced. Generally,
after conversion, a blister copper is produced that is
subsequently refined in the same plant or sold or
transported to other plants.
Air emissions from converter type operations are severe and
air pollution control devices, such as baghouses,
electrostatic precipitators, or scrubbers, are usually
employed. When wet scrubbers are used to control emissions,
the waste water is treated before recirculation or
discharge. Waste water may also be generated if water is
used for granulation of the hot converter slags formed
during the operation. The converter slags contain copper,
which is usually recovered in cupola or blast furnaces.
Water used to cool and condition the gases for electrostatic
precipitators and baghouses is discharged as steam.
Crucible Furnaces. Crucible furnaces are refractory lined
cylindrical furnaces with a vertical axis. The crucible is
supported by a refractory stool in the center of the
furnace. The furnaces are heated by the combustion of gas
or oil in the annular space between the crucible and the
refractory wall. This indirect firing prevents contact of
the combustion products with the charge. Crucible furnaces
are generally used to melt small quantities of clean scrap
to produce special alloys. No water is used in this type of
furnace operation.
Induction Furnaces. Induction furnaces are electric
furnaces heated by either high or low frequency induction
heating techniques. Furnace sizes range from a few pounds
to several tons. Small furnaces are used to melt and refine
precious metals recovered from slimes from electrolytic
refining. Intermediate sizes are used to melt special
alloys or high purity materials. The intermediate sizes may
22
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be lift-out crucible furnaces. Larger sizes may be used for
general melting and refining. A small amount of metal fumes
may be vented to the air cleaning system. Induction
furnaces and their power sources are water-cooled. This
noncontact cooling water is usually of good quality and is
recirculated after cooling or discharged without treatment.
Summary of Water Usage in Melting Furnaces. Large volumes
of water are generally used to water cool the outside of the
lower section of blast furnaces or cupolas. Large volumes
of water are also used to quench and granulate slag from
these furnaces, when this method of handling slags is
employed. Both of these large volumes of water generally
are recirculated for economic reasons. Water used to
granulate slags would be expected to be contaminated with
soluble and insoluble materials in the slag.
Large volumes of water are used by some plants when wet air
pollution control equipment is used instead of dry baghouse
equipment. The water is normally recirculated for economic
reasons. Contamination is always severe, because the water
will contain all of the pollutant materials originally in
the air, such as zinc oxide and other alloying metal oxides.
Large amounts of water are used in induction furnaces to
cool the induction coils (or inductors) and to cool the
electrical power source. This water, since it is employed
in noncontact cooling, is not contaminated, except
thermally.
Appreciable amounts of water are used to cool the doors of
some reverberatory or rotary furnaces. This water is not
contaminated, except thermally.
No water is used with fuel-fired crucible furnaces.
Smelting and Alloying Intermediate Grade Copper Based Scrap
Copper based scrap metals, intermediate grade copper metal
scrap, black and blister copper, and residues with known
origin or composition are melted, refined, and alloyed, if
necessary, to produce either brass or bronze ingots of
specific composition. These same materials are refined
further to produce fire refined copper suited for end use or
for casting anodes for electrolytic refining. Direct fired
reverberatory and rotary furnaces are used to produce the
product metals, brass and bronze, and fire refined copper.
In the production of brass and bronze ingots, the extent of
refining is usually small, if the scrap is well sorted. If
23
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the residues are of known origin (usually a toll recovery
operation), refining is also kept to a minimum. In the
production of copper, the extent of refining is greater.
The chemical principles of refining are applicable to both
brass and bronze ingot manufacture and the preparation of
fire refined copper.
In the refining step, impurities and other constituents of
the charge, present in excess of specifications, are reduced
or removed by chemical reaction with oxygen. Elements, such
as iron, manganese, silicon, and aluminum, are normally
considered to be contaminants in copper base alloys and must
be removed by refining. In the preparation of refined
copper, the alloying elements common to brass and bronze
must also be removed. The methods employed in refining vary
with the type of furnace, the types of scrap in the charge,
and the experience and training of the personnel, as well as
the type of product being produced.
The chemicals used in refining are air or oxygen-enriched
air and solids employed to modify the slag cover or to
modify (and alloy) the melt. Air is blown into the molten
metal bath with lances in order to oxidize metals in near
accordance with their position in the electromotive series.
Thus, iron, manganese, aluminum, and silicon are .oxidized,
and in the refining of zinc-rich copper alloy scrap, the
loss of zinc is unavoidable. In the production of refined
copper, the blowing is for a longer duration, since most of
the metal elements must be removed.
The oxidized metals form a layer en the surface of the melt,
since the oxides have a lower density than the metal. These
oxides combine with the slag cover, which is usually added
to aid in the removal of the oxidized impurities. Fluxes
and silica or glass are added to control the fluidity of the
molten slag cover. The slag cover protects the molten metal
surface from unwanted oxidation and reduces volatilization
of zinc. The slag cover is maintained between 6.4 and 12.7
mm thick (0.25 to 0.50 inch), depending on the type of melt
being processed.
Borax, slaked lime or hydrated lime, glass or silica, soda
ash, rasorite, and caustic soda are all used as fluxes to
modify the characteristics of the slag cover. The most
common material used by the brass and bronze smelter is
anhydrous rasorite, a sodium borate flux (Na£B<*02), which
has great affinity for metal oxides and siliceous materials.
Its fluidity can be easily adjusted and the quantities used
are about 2 to 3 percent by weight of the charge.
24
-------
To deoxidize or degasify, as well as to alloy, a brass or
bronze melt, metal fluxing agents are added to the melt. In
almost all cases, these melt modifiers are binary alloys of
copper with silicon, phosphorus, manganese, magnesium,
lithium, or cadmium. The highly oxidized, refined copper
melt, containing an appreciable amount of Cu2O can be cast
from the reverberatory or rotary furnace into blister copper
shapes and used in the subsequent preparation of fire
refined copper. More typically, however, the molten
oxidized melt is reduced in the reverberatory or rotary
furnace in which it was formed, by using carbon based
reducing agents and then poling. These operations are
discussed in detail in the section on refining of high grade
copper scrap.
Once a melt meets specifications, principally chemical
analysis, the brass or bronze is cast into ingots, cooled,
and then packaged for shipping. Refined copper, that has
been analyzed and found to meet specification, is either
cast into blister copper ingots or is subsequently reduced
in the furnace as a continuation of the fire refining
operation.
Reverberatory Furnace Operations. The reverberatory furnace
is a rectangular boxlike structure, refractory lined, that
uses direct firing to heat the charge by conduction and
radiation. The furnace is charged either through the top,
through side doors, or, occasionally, through the flue and
may be stationary or tilting. Water is sometimes used to
cool the doors on the reverberatory furnace.
Stationary reverberatory furnaces have capacities ranging up
to 250 tons of metal per charge. Tilting reverberatory
furnaces are somewhat smaller. These are the basic
production units for large runs of the more common copper
base alloys. The furnace is charged with scrap metal at the
start of the heat and at intervals during the melt down
period. The fuel is normally natural gas or oil. The air
may be enriched with oxygen or preheated to increase the
melting rate. The bath of metal in the hearth is normally
coated with a thin layer of fluxed slag to protect it from
oxidation and volatilization. Air pollution control is
practiced on the exhausts from smelting furnaces. When wet
air pollution controls are used, a waste water is generated.
The metal produced in a reverberatory furnace can be a
specification brass or bronze alloy that has undergone some
refining, followed by alloying. It can also be a blister or
a refined copper. Slags removed from reverberatory furnaces
contain copper values, which are recovered in cupola or
25
-------
blast furnaces. Slags produced by small secondary plants
are sold to larger secondary smelters or even to primary
smelters equipped to recover the metal value. Waste water
is generated when water is used for reverberatory slag
quenching or granulation.
Rotary Furnace. Rotary furnaces are refractory lined,
barrel shaped furnaces, that are fired with gas or oil in
one end, and exhaust the combustion products through the
opposite end. The furnaces rotate either 360 degrees or
back and forth through 180 degrees or less during operation.
The furnaces can be either tilting or nontilting. The
charging, alloying, fluxing, and sampling procedures are
similar to those used in the reverberatory furnace. This
type of furnace is the basic melting unit for smaller heats
of copper base materials. Water is used in this type of
furnace operation for noncontact cooling of bearings. Waste
water is also generated when slags from rotary furnaces are
quenched or granulated with water. When wet scrubbers are
used in the control of emissions from rotary furnaces, a
waste water, that requires treatment before recirculation or
discharge, is generated. Available sampling data indicates
that rotary furnaces tend to contribute greater amounts of
suspended solids and metals to emissions scrubwaters than
reverberatory furnaces, which is apparently the result of
the agitation of the melt as the rotary furnace revolves on
its axis.
Refining High Grade copper Scrap
Black copper produced from smelting of low grade scrap,
slags, drosses, and sludges, and blister copper prepared
from intermediate grade scrap, are eventually brought
together with high quality copper scrap (usually No. 2
copper wire, No. 1 heavy copper, No. 2 copper, and light
copper) for full fire refining. Full fire refining is
required to produce specification copper billets, slabs,
cakes, and wire bars. Copper ingots and shot are also
produced for making copper base alloys. Fire refined copper
may be even further refined by casting the metal into anodes
for electrolytic refining. The extent of refining is
governed in part by the amount and type of metal impurities
and the need for or difficulty of their removal (by fire
refining) to meet specifications for the product.
Fire Refining. Part of the secondary copper production at
some (but not all) plants in the industry is fire refined by
blowing air or oxygen through the molten metal to remove
excess zinc and iron in a reverberatory or rotary furnace.
Most metallic impurities, including lead, tin, and zinc, are
26
-------
undesirable impurities in high purity copper products. In
the production of essentially pure copper products, the
blowing is continued until essentially all of the contained
zinc, lead, iron, tin, and other impurities, along with
about three percent of the copper, are removed by oxidation.
Most of the oxides are trapped in the slag cover. After the
contaminated slag is removed, the refined copper is
deoxidized with green wood poles under a charcoal or coke
cover. Once the oxygen content meets specifications, the
copper is cast into anodes for electrolytic refining or into
billets, wire bars, etc. Selected types of flux materials
are generally added to assist in the removal of the
impurities before poling. The slags may contain various
proportions of the fluxes, silica, iron oxide, phosphorus
pentoxide, soda ash, rasorite (a borax type flux), and
limestone depending on impurities needed to be removed to
obtain the desired composition. Copper rich slags are
reprocessed or sold for that purpose. Copper poor slags are
discarded or sold.
Skimming. After a heat of copper alloy has been refined in
a reverberatory or rotary furnace, it is analyzed, adjusted
in composition if necessary, adjusted to the desired
temperature, and skimmed to remove the slag containing the
impurities. These slags are generally reprocessed to remove
copper values trapped in the slag. The slag may be
processed by the smelter or sold to larger smelters for
processing. The slags are either crushed wet or dry and wet
screened or tabled to concentrate the copper content, or the
entire copper rich slag may also te charged into a blast
furnace or cupola for remelting and separation of the copper
from the other ingredients. If the metal content of the
slag is 45 percent or above, some facilities will charge the
slag directly into a rotary or reverberatory furnace. Waste
water is generated in plants that use wet crushing and
concentrating.
Electrolytic Refining. One secondary copper smelter
discharging to a POTW practices electrolytic refining in
order to produce a high-purity cathode copper. Anode
copper, often containing precious metals and impurities such
as nickel, are placed into the cells in an alternating
fashion with thin copper starter sheets, which after
electrolytic deposition become cathodes of refined copper.
The cathodes are removed periodically from the electrolytic
cells, are washed to remove adhering acid, and are then
melted and cast into fine-shape castings, such as wire bar
and billets. Having been greatly reduced in size during the
electrolytic process, the used anodes are removed from the
cells and remelted into new anodes. If nickel is present in
27
-------
the anodes, as is the case at Plant A (a direct discharger
described in Table 4), the nickel content of the
electrolyte, as well as the copper content, will build up
and a bleed from the circuit must occur. This bleed is
often subjected to electrowinning for copper removal,
wherein a lead cathode is used, and cementation. The spent
electrolyte, depleted in copper content, may be partially
evaporated by open or barometric condensers in order to
produce nickel sulfate as a byproduct. Precious metals are
recovered as a slime in the bottom of the electrolytic cells
and are usually dried and sold to ether facilities for
precious metal value recovery. One domestic secondary
copper facility, Plant A, performs on-site recovery of
precious metals.
Postelectrolytic Melting and Refining. Refined copper in
the form of cathodes along with Nc. 1 copper wire scrap are
melted in reverberatory furnaces or shaft furnaces and cast
into desired product shapes such as cakes, billets, and wire
bars, as well as ingots. The melting process in the
reverberatory furnace may be followed by a blowing step,
skimming of the melt, and then poling, followed by
preparation for pouring and casting.
The shaft furnace, which uses natural gas as a fuel and
operates on the principle of a cupola furnace, continuously
melts cathodes, home scrap, and No. 1 copper wire scrap,
with "refining" by poling or charcoal reduction being done
in a small reverberatory holding furnace just before
casting. The molten copper is continuously cast into
billets and cakes. Water is used principally for noncontact
cooling in the two types of melting furnaces. Particulate
air emissions from the operation are usually controlled by
means of baghouses. Wet air pollution control may also be
used to control air emissions. In such cases a waste water
is generated.
Pouring and Casting of Final Product
Molten metal from the smelting operations described above as
cast into various shapes suitable for shipping, handling, or
use in subsequent operations. Copper-base alloys are
usually cast into ingots. Black copper, blister copper, and
anode copper are also cast in molds and shapes suited for
the specific product. Refined copper is cast into shapes
suitable for subsequent fabrication steps, taking the form
of billets, cakes, wire bars, wire rod, and ingots, or it
may be quenched into shot. Water use in each product line
is considered separately.
28
-------
Brass and Bronze ingot. The melt, which has been
analyzed and found to meet specifications, is adjusted to
the proper temperature before pouring. Rotary and
reverberatory furnaces containing the molten metal are
tapped, and the metal is poured into various ingot filling
systems. The metal may pour directly into a moving,
automatically controlled mold line, in which one or more
molds are filled at once; then the flow shuts off while a
new set of molds moves into position on an endless conveyer.
In another variation, the metal from the furnace is tapped
into a ladle and then moved to a irold line, which may be
stationary or movable. Molds are sprayed with a mold wash
and then dried thoroughly before the ingot is cast.
Automatic devices are often used to sprinkle ground charcoal
in the molds or onto the molten metal in the molds to
provide a special smooth top on the ingots.
The molds are cooled by a water spray or partial immersion
of the mold in a tank of water. Once the molten metal has
solidified, the ingots are quenched in a pit from which they
are removed by a drag conveyer. After drying, they are
packed for shipment.
Generally, only steam is discharged during the operation,
and water is recycled after cooling and storage in tanks or
ponds. The waste water is discharged periodically to permit
the storage tanks to be cleaned of charcoal and mold wash
sludges containing some metals or their oxides.
Black and Blister Copper. Black copper (or cupola melt)
produced from blast or cupola furnace operations is usually
transported or transferred to a converter or a reverberatory
or rotary furnace in the molten state to conserve heating
requirements. In some cases where the conversion oriented
operation is backlogged or out of synchronization with black
copper production, the black copper might be cast into
convenient shapes for later use. These shapes take the form
of shot, pigs, sows, or any convenient mold shape available.
Crude molds formed in sand are often employed to cast pigs,
sows, or other shapes. Blister ccpper production may also
be out of phase with subsequent reduction operations due to
a furnace failure or plant shutdown. In such cases, the
blister copper is cast into almost any available mold shape
for subsequent use. These molds may be contact or
noncontact cooled with water, or they can be air cooled. In
those cases where the blister copper is an end product of
the smelter, the molds are made of graphite and are air
cooled.
29
-------
Anodes. Partially fire refined copper, that is to be
electrolytically refined to remove impurities that are not
removed by fire refining or to recover impurities of value,
is cast into anodes. The molten metal from the anode
furnace is cast in a circular mold conveying system (known
as a casting wheel) or a conveyer. The molds may be cooled
indirectly, or spray cooled, or both, after the metal has
been cast. Once the molten metal has solidified, it is
removed from the mold and quenched in a tank of water. The
mold is treated with a mold coating or "wash", commonly
synthetic bone ash (calcium phosphate), before receiving the
next charge of molten anode copper. Much of the spray water
is converted to steam. Waste water containing residual mold
wash and some metal oxide scale is generated.
Refined Copper. Fully fire refined copper and melted
cathode copper are cast into various shapes suitable for
fabrication end use. These shapes are billets, cakes,
slabs, wire bar, wire rod, and ingots. Wire bar and ingots
are cast into permanent molds on a casting wheel that is
internally cooled with water. Once solidified, the wire bar
or ingots are removed from the mold and quenched in tanks.
The molds are treated with a mold wash and dried before
reuse.
Billets, cakes, and wire rod are usually continuously cast
or direct chill cast, and the metal is cooled within dies
using noncontact and contact cooling water that is
recirculated after passing through cooling towers. Wire-rod
casting uses exclusively noncontact cooling water as the
cast rod is reduced in diameter through a series of water
cooled rolls. In each case, only noncontact cooling water
is generated, and this is cooled and recirculated.
Waste water generated in casting finished copper shapes is
primarily noncontact cooling water. The production of wire
bar and ingots does produce a contaminated waste water.
copper Shot. Copper for alloying purposes is sometimes
produced in the form of shot to facilitate handling and
remelting. In some cases, the copper is alloyed with
phosphorus to increase hardness. Copper shotting operations
consist of pouring the molten refined copper directly into a
quench pit. In one case, the metal is poured into a water-
filled cast iron vessel which in turn is inside a twelve-
foot deep pit. The shot is retrieved by lifting the pot
from the pit, followed by a screening and sizing operation.
In another case, selected copper scrap is melted, along with
phosphorous, in a 3,000 Ib. capacity electric furnace. The
phosphor copper is poured into a 15,000 gallon quench pit to
30
-------
form shot. A flat vessel with appropriately spaced holes is
used to break up the flow of the molten metal into the pit,
thus producing a more uniform shot. The phosphor copper
shot is collected in a basket, drained, dried and sized.
In all cases, waste water is generated when the quench pit
is periodically discharged for cleaning, and by wet air
pollution control devices operating on gas streams generated
by the melting furnace. Waste water from phosphor copper
operations is usually quite acidic, probably due to the
formation of phosphoric acid.
Products
Brass and Bronze. The types of copper-base alloys produced
by ingot makers are the basic 31 standard alloys established
by the Brass and Bronze Ingot Institute. Hundreds of other
specialty alloys are also produced.
Refined Copper. Although some smelters of copper will sell
black, blister, and anode copper as their end product, the
major volume is in the various grades of fire refined and
electrolytic refined copper. The end use of the metal will
specify the purity required. Tubing, pipe, etc., require
less pure copper than that required for electrical
conductors used in power transmission or communication
equipment. Typical grades of refined copper are tough
pitch, deoxidized, electrolytic, and oxygen free.
Description of Secondary Copper Industry
Segment Discharging to POTW
Of the forty-six secondary copper smelters and refiners in
the United States, eleven discharge process waste waters
directly to streams or other water bodies and seventeen
discharge to POTW. Seventeen plants do not discharge
process waste waters, although one of these discharges a
portion of its non-contact cooling water to a POTW. One
additional plant was identified just prior to the
publication of this document, and although it was determined
that this plant does not discharge process waste waters to a
POTW, it could not be determined whether or not this plant
discharges process waste waters tc navigable surface waters.
There are no significant locational patterns which
differentiate between those secondary copper smelters and
refiners discharging to POTW and direct dischargers. The
industry as a whole is concentrated in the eastern and
midwestern United States, with only three of the forty-six
smelters located in the West, and only two in the South.
31
-------
Comparisons of productions between direct dischargers and
dischargers to POTW reveal some significant differences as
shown in Figure 2. In general, direct dischargers are
larger plants, although the largest secondary copper smelter
and refinery discharges to a POTW. As shown in Figure 2,
the largest frequency of direct dischargers produce between
1,000-5,000 ton/month of copper metal, whereas the largest
frequency of indirect dischargers produce between 100-500
ton/month of copper metal.
The metal smelting and refining processes employed by plants
which discharge to POTW do not differ singificantly from
those which discharge directly to navigable waters,
including those which do not now discharge process waste
waters. Table 1 compares the frequency of these processes
and operations between direct dischargers and indirect
dischargers. As seen in this table, no slag milling and
classification operations were found at plants introducing
pollutants to POTW. slag quenching and granulation
operations are performed at only one indirect discharger
(out of seven in the industry that perform this operation).
The frequencies of metal cooling, wet emissions scrubbing
and electrolytic refining between direct dischargers and
indirect dischargers are not significantly different.
Type and Size of POTW. Publicly owned treatment works
receiving process wastewaters from secondary copper smelters
and refiners include primary treatment plants (i.e., plain
sedimentation) and secondary treatment plants (i.e.,
activated sludge, trickling filter) . Sizes of primary
plants receiving secondary copper process wastewater range
from 4 MGD to 350 MGD. Secondary treatment plants receiving
wastewaters from secondary copper operations range in size
from 11 to 900 MGD. The largest of these plants (900 MGD)
receives effluent from three secondary copper plants. There
are fifteen POTW receiving process water effluents from
secondary copper smelters; one of these is now being
converted to a physical-chemical treatment plant, and the
remaining fourteen employ biological waste treatment
systems. A size frequency distribution of primary and
secondary POTW receiving process effluents from secondary
copper plants is given in Table 2.
It should be noted that the smallest primary treatment plant
receiving process wastewater from a secondary copper smelter
(4 MGD) is being replaced by a 12 MGD secondary plant and a
120 MGD primary plant receiving copper process wastes will
be converted to secondary treatment. In addition, an 11 MGD
primary plant is presently being converted to an 11 MGD
physical-chemical treatment plant. As a result of the above
32
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FIGURE 2 PRODUCTION DISTRIBUTION, SECONDARY COPPER SMELTING AND REFINING*
SIZE CLASS: A
B
C
D
E
PRODUCTION
metric tons/month
<90
91 - 453
454 - 906
907 - 4534
4535 - 22,680
short tons/month
<100
100 - 499
500 - 999
1000-4999
5000 - 25,000
B C D
SIZE CLASS
*The Percentage of Plants for Which Production Data is Available for Each
Type of Discharger is as follows:
Direct Dischargers (incl. zero dischargers) 89%
POTW Dischargers 100%
33
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TABLE 1. PROCESS OPERATION FREQUENCY-SECONDARY COPPER
SMELTING AND REFININGt
UJ
Direct Dischargers
POTW Dischargers
Wet Emissions*
Control
36%
35%
Metal
Quenching
82%
100%
Slag
Granulation
18%
6%
Electrolytic
Refining
11%
6%
Noncontact
Cooling
68%
41%
Slag Milling
and
Classification
21%
0%
Reported as percent of plants where data is available.
* Wet and dry emissions control can both be practiced at the same plant.
-------
TABLE 2. SIZES OF POTW RECEIVING SECONDARY COPPER
PROCESS EFFLUENTS*
Primary
Secondary
Size Class m3/day
(MGD)
< 37850
«10) .
0
0
37850 - 189250
(10-50)
2
4
193035 - 378500
(51-100)
0
2
> 378500
(> 100)
0
5
Total
2
11
•Number of POTW includes those under construction or in advanced plan-
ning stages. Data available for 13 of the 17 POTW receiving process
wastewater from secondary copper plants.
35
-------
changes, no plant smaller than 10 MGD will be receiving
secondary copper process effluent. Twenty percent of the
plants receiving secondary copper effluents will be primary
plants while eighty percent will te secondary, including one
physical-chemical treatment plant.
36
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SECTION IV
INDUSTRY CATEGORIZATION
This section describes the characteristics of the segment of
the secondary copper industry which discharges to POTW, and
whether there is sufficient reason for subcategorization
within this industry segment.
Objectives of Categorization
The objective of categorization of the secondary copper
industry segment discharging to POTW is to establish
pretreatment standards for existing sources which are
specific and uniformly applicable to a given category.
Factors Considered
A study was made of the secondary copper industry, covering
such factors as raw materials used, product line, processes
employed, water usage, plant age, plant location, and plant
capacity. All seventeen plants which discharge to POTW were
studied. Of the total, nine produced brass and bronze
ingots only, two produced only refined copper, and six
produced both products. Seven plants, including plants in
both product lines, were visited by interviewing teams.
Twelve additional plants in the industry were visited by
interviewing teams in 1973, and this information is included
in this consideration.
The results of the study indicate that the secondary copper
industry should be considered as a single category.
Rationale for this judgment is given below.
Results of the Industry Inventory
Some of the information obtained in the industry survey of
the seventeen plants is tabulated in Table 3. This table
contains information on fifteen plants producing brass and
bronze ingot, such as their production or capacity, the
number of people employed, products, water use, and waste
water treatment and disposition. Water uses noted are in
air cleaning, cooling or quenching molten metal, equipment
cooling, and quenching and granulation of slags. Brass and
bronze ingots are used as raw materials in foundries or
fabricating plants to make brass cr bronze products.
Of the eight plants which produce refined copper, one
produces electrolytically refined cathode copper, and all
37
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TABLE 3. CHARACTERISTICS OF SECONDARY COPPER SMELTERS AND REFINERS - POTW
DISCHARGERS
PLANT
CODE
1
2
3
4
5
8
9
to
11
12
13
14
15
16
17
18
19
COPPER BASED
PRODUCT
BB ingots
BB ingots
Copper shot
BB ingots
Copper Shot
Cathode
Billet
BB ingots
BB ingots
Copper shot
BB ingotl
BB ingots
Phosphor-cooper
BB ingots
BB ingots
BB ingots
Phosphor-copper
BB ingots
BB ingots
BB ingots
BB ingots
Copper shot
BB ingots
Phosphor -copper
AVERAGE
PRODUCTION
Metric Tons
per month
363
454
32
181
3175
3628
272
658
363
WITHK
154
23
245
227
245
454-816
680
1814
(cap)
Short Tom
per month
400
500
35
200
3SOO
4000
300
725
400
ELD
170
25
270
250
270
500-900
750
2000
(cap)
WATER USE
Emissions Control
Dry
Dry
No emissions control
No emissions control
Wet
Dry
Dry
Dry
Wet & Dry
Wet
Dry
Wet
Dry
Dry
Dry
(H_O for condition-
ing)
Wet & Dry
(H_O for quench-
ing
Wet & Dry
Metal
Quenching
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Non-
Contact
Cooling
No
No
No
No
Yes
Yes
Yes
No
Yes
Yes
No
Yes
No
No
No
Yes
No
Slag
Granulation
No
No
No
No
No
No
No
No
Yes
No
No
No
No
No
No
No
No
Electrolytic
No
No
NO
No
Yes
No
No
No
No
No
No
No
No
No
No
No
No
DISCHARGE TO POTW
Cubic meters
114 m3/day
3.4 m3/year
7 6 m3/ month
6430 m3/day
160 m3/day
379 m3/day
1 5 m3/day
570 m3/day
76 m3/day
1.9 n.3/day
4-5 days/month
2880 m3/day
10 days/ month
10.6 m3/week
9 1 m3/day
57m3 e«. 3-t
months
1.1 m3/day
26 m twice per
year
1 10 m3/day
1 1 7 m3/day
Gallons
3.000 GPD
900 gal per year
2,000 gal per
month
1.7MGD
42 300 GPD
100,000 GPO
400 GPD
150,000 GPD
20,000 GPD
500 GPD
4-5 days/month
760,000 GPD
10 days/month
2,800 gal per
week
2.400 GPD
1.500 gal. av
3-4 months.
300 GPD
7.000 twice per
year
29,000 GPD
3,100 GPD
PRETREATMENT
None
None
None
None
Emissions control water, contact and non-contact cooling partially
recycled. Electrolytic wastewater not pretreated
Noncontact cooling water partially recycled. Ingot quenching water
partially recycled
Noncontact cooling water partially recycled Ingot quenching
water partially recycled.
None
Scrubber water partially recycled with discharge neutralized Slag
granulation and ingot quench water not pretreated Noncontact
cooling partially recycled.
Emissions control water partially recycled. Ingot quenching water
recycled Noncontect cooling not pretreated
None
None.
None.
None
None.
Emisnonsquenching water eveporated
Contact & noncontact cooling water not pretreated.
Phosphor-copper shotting water and scrubber water neutralized
Ingot quenching water totally recycled.
UJ
oo
-------
eight, including the electrolytic refiner, produce fire
refined copper. Electrolytically refined cathode copper is
suitable for the production of the highest quality copper
products, such as pipe, tubing, or high conductivity copper
wire. Fire refined copper may be capable of meeting the
specifications for pipe or copper wire, but generally
contains more impurities than cathode copper. Black copper,
the crude product from cupola or blast furnace melting,
must be further refined before final use, although it has
been reported that some plants in the industry sell this
intermediate product to other smelters for subsequent
refining.
That portion of the industry that discharges to navigable
waters directly (including those plants that discharge no
process waste water) was also studied. Information relating
to the twenty-eight such plants is presented in Table 4.
One additional plant (Plant CC) was identified just prior to
the publication of this document, and data relating to the
operation of this plant is not included since such
information was not immediately available.
Industry Profile - Indirect Dischargers
From the information given in Table 3, the following listing
summarizes the distribution of plants exhibiting some of the
relevant features to be considered in potential
subcategorization of the industry. Only indirect
dischargers are considered in this analysis.
Feature
Current Production
(or Capacity)
short tons per month
Less than 100
101-499
500-999
1000-4999
5000-25,000
Product Line
Copper-base alloys
Fire refined copper only
Electrolytic and fire
refined copper
Combination of alloys and
refined copper
No. of Plants
(Percent)
2
8
4
2
1
9
1
1
6
(12)
(47)
(23)
(12)
(6)
(53)
(6)
(6)
(35)
39
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TABLE 4. SECONDARY COPPER AND BRASS AND BRONZE SMELTERS -- DIRECT DISCHARGERS
(Summary of 1973 EPA survey)
Metric
(Short)
Company Employees Tons/Mo
A 1,800 15,900
(17,500)
B 169 3,630^)
(4,000)
C 120 814
(900)
o
D 40 225
(250)
E 180 l,360(b)
(1,500)
F 125 2,270
(2,500)
Air
Product Cleaning
OFHC Wet, dry
copper § electro-
static
BB ingots Dry
BB ingots Dry
(Quench
BB ingots Plans
Other dry
Nonferrous
Metals
Cathode Wet and
copper dry
(Quench and
BB ingots Dry
Quench
Molten
Metal
Yes
No
Water Use
Electro-
Cooling lytic
Yes Yes
Yes No
reverb .
door
Yes Yes No
and granulate slags)
Yes
Yes
granulate
Yes
Yes No
Yes Yes ,
no dis-
slags) charge
Yes No
Liters
(Gallons)
/Day
125M(a)
(33M) City §
Bay
Small amount
city
(24,000)
136,000
(36,000)
City
Lake
16M
(4.2M)
329,000
(87,000)
Water Treatment
and Remarks
None; discharged
into bay
None discharged
Settling basin, re-
circulated, no
discharge
None; discharged into
lake
No discharge
normal ly ; overflow
to river
None discharged;
all filtered and
(Quench and granulate slags)
recirculated
-------
TABLE 4. (continued)
Metric
(Short)
Company Employees Tons/Mo
G 200 2,270
(2,500)
H 200 2,720
(3,000)
I 60 455
(500)
J 150 1,360
(1,500)
f— l
K 50 N.A.
L (No
N 890 815
(900)
0 100-150 (?)
Air
Product Cleaning
BB ingots Electro-
static
Cathode Dry
copper
Water Use
Quench Electro-
Ingots Cooling lytic
Yes No No
(Wet milling
of slags)
Yes Yes Yes
BB ingots Dry Yes No No
(Wet crushing and concentrating slags)
Black § Wet
blister and
copper dry
BB ingots Dry
(Electro-
static)
data supplied)
BB castings Dry
(?) Dry
BB
No Yes No
(Quench and granulate slags
and quench copper shot)
Yes Yes No
Yes No No
No No No
Liters
(Gallons)
/Day
545,000
(144,000)
2.73M
(720,000)
9
220,000
(58,000)
9
City §
Ground
9
Well
1.87M
(495,000)
Water Treatment
and Remarks
None discharged;
recycled
All recycled, with
discharge from lake
(new plant)
Recirculated ;
settling tank
Scrubber water
filtered and re-
circulated; no
discharge
None discharged; all
recirculated
No discharge
No treatment; dis-
charge to a stream;
small amount
Direct discharge
-------
TABLE 4. (continued)
Metric
(Short)
Company Employees Tons /Mo.
P ? 55
(60)
Q 8 90
(100)
R 750 3,630
(4,000)
£ S 30 l,360(b)
(1,500)
T 15 320
(350)
U 40 2,720
(3,000)
V 40 225
(250)
Product
BB ingots
BB ingots
shot
Wire bar,
rod
BB ingots
BB ingots
Copper
billets
BB ingots
Air
Cleaning
Wet
Water Use
Quench Electro-
Ingots Cooling lytic
Yes No No
(non-
contact)
Liters
(Gallons)
/Day
?
None Yes No No ?
(Water used to make shot)
Electro-
static
(wet and
dry)
Dry
Wet
None
Yes Yes No
(non-
contact)
Yes No No
No No No
Yes Yes No
Wet Yes Yes No
( Wet grinding and classification
of slags)
1.14M
(300,000)
7,600
(2,000)
City
102,000
(27,000)
91,000
(24,000)
City
Water Treatment
and Remarks
None discharged
None discharged;
all recycled
All process waste
water combined and
treated before
discharge
None; discharged
into storm sewers
None discharged;
recycled
Only boiler water
discharged; all
other water recycled
All recirculated
-------
TABLE 4. (continued)
Metric
(Short)
Company Employees Tons /Mo.
W 70 910
(1,000)
X 85 l,000(c)
(1,100)
Y 275/325 1,815
(2,000)
ji.
00
Z 20 225
(250)
AA 120 360
(400)
BB 21
(23)
1238
(1365)
Water Use
Air Quench
Product Cleaning Ingots Cooling
BB ingots Wet and dry Yes No
(Wet grinding and classification
of slags)
(Quench and granulate slags)
BB ingots Dry Yes No
(Wet grinding and classification
of slags)
BB ingots, Wet Yes Yes
other (3 units)
metals (Wet grinding and classification
of slags)
BB ingots Dry Yes Yes
(901
complete)
BB ingots Dry Yes Yes
BB shot Wet Yes Yes
Other metals
Liters
Electro- (Gallons)
lytic /Day
No 142,000
(37,500)
No 45,000
(12,000)
No Wells
76,000
(20,000)
No ?
Wells
No 350,113
(92,500)
No 4,572,300
(1,208,000)
Water Treatment
and Remarks
No discharge
Settling pond then
discharged into
storm sewers
None discharged;
all recirculated
None discharged;
all process water
softened and
recycled
No discharge
Direct discharge
-------
TABLE 4. (continued)
Water Use
Metric Liters
(Short) Air Quench Electro- (Gallons) Water Treatment
Company Employees Tons/Mo Product Cleaning Ingots Cooling lytic /Day and Remarks
CC (No data supplied) Does not discharge
to POTW
DD BB Ingots Dry Yes No Direct discharge
(a) M = million
fb) Capacity not average production
(c) Includes nickel production
-------
- No. of Employees
Less than 50 7 (41)
50-100 2 (12)
101-300 1 (6)
301-1000 1 (6)
Undetermined 6 (35)
Air pollution control systems, in use ty the plants studied,
are displayed in Table 5. Air pollution control is used on
blast or cupola furnaces, on electric, reverberatory or
rotary furnaces, and occasionally on furnaces used in the
preparation of scrap for the smelting process (e.g., the
removal of oils and low-melting point metals). Plants may
also control fugitive dust in the plant. Of the plants
studied, 53 percent use dry air pollution control only. All
of the plants using wet air pollution control employ partial
recycle of the waste water.
Water usage by the industry was estimated from the data
supplied in the study and is summarized in Table 6 for each
segment of the industry. The trass and bronze ingot
producers use, on the average, less water per ton of product
than do the refined copper producers. There are, however,
plants that are exceptions in each segment.
The specific processes in which water is used and the source
of the process water as determined from the study are given
in Table 7. All plants use water for molten metal contact
type cooling, seven use water for emissions scrubbing, one
plant uses water for slag granulation, and one plant uses
water for electrolytic refining.
Factors
Factors taken into consideration for subcategorizing the
secondary copper industry include raw materials processed,
products, processes, plant size, air pollution control
techniques, and plant location. Application of each of
these categorization factors leads to uncertainties in
subcategorization, as described in the following rationales.
Raw Materials. The principal groupings of raw materials
used in the secondary copper industry are (1) low grade
scrap (residues and copper-rich slags) , (2) intermediate
grade scrap (solids), and (3) high grade scrap (solids).
The scrap is purchased primarily for its copper content.
Each establishment utilizes at least one of these scrap
sources. However, many establishments use all three grades.
Although brass and bronze ingot makers can produce their
products from intermediate grade scrap, some use low grade
45
-------
TABLE 5. Distribution of Air Pollution Control Processes Used
by Secondary Copper and Brass and Bronze Smelters
(POTW Dischargers)
Number of Plants
Control Process B § B Copper Both Total
Plants Surveyed 9 2 6 17
Only Dry Control 8019
Only Wet Control 1113
Both Types 0033
No Control 0 112
46
-------
TABLE 6. Water Usage by the Secondary Copper and Brass
and Bronze Smelting Industry (POTW Dischargers)
Gal/Ton
Company Code (Metal)
Brass and Bronze Production
1 75
2 0.2
8 4290
10 30
12 3529
13 100
15 45
16 267
17 18
Companies 9
Max 4290 gal/ton
Min 0.2 gal/ton
Ave 928 gal/ton
Refined Copper Production
3 857
5 6800
Companies 2
Max 6800 gal/ton
Min 857 gal/ton
Ave 3828 gal/ton
Combination of Copper and Brass and Bronze Production
9 4195
14 28,148
18 1176
19 47
Companies 4
Max 28,148 gal/ton
Min 47 gal/ton
Ave 8102 gal/ton
47
-------
TABLE 7. Water Usage by Secondary Copper and Brass and Bronze
Smelters and Refiners (POTW Dischargers)
Number of Plants (Percent)
Process B § B Copper Both Total
Wet Emissions Control 1146 (35)
Contact Metal Cooling 9 2 6 17 (100)
Noncontact Cooling 2147 (41)
Slag Granulation 0 0 1 1 (6)
Slag Milling 0000
Electrolytic Refining 0 1 0 1 (6)
48
-------
scrap and most use high grade scrap. Most facilities are
equipped to handle a range of scrap grades and in fact may
smelt different grades of scrap, depending on market
conditions.
A distinction could be drawn between those operations which
process residues (low grade scrap) and those that do not,
since the operations are always different. Residues are
processed either by wet milling and classification or in a
blast or cupola furnace, while intermediate and high grade
scrap is processed in rotary, crucible, electric, or
reverberatory furnaces. It was found that no plants
discharging to POTW perform wet milling and classification,
and it was found that the effluent streams associated with
blast or cupola furnaces (emissions scrubwater and slag
granulation water) are similar to the effluent streams
associated with the smelting furnaces used for smelting
intermediate or high grade scrap. Therefore, on the basis
of raw materials, a single category is most suitable for
establishing pretreatment standards.
Products. Subcategorization of the industry into producers
of brass and bronze ingots and producers of refined copper
was considered. However, in the comparison of the
metallurgical steps involved in (1) converting the. scrap
material into brass and bronze ingot with (2) those steps
used in producing refined copper, the differences in the
steps are only in the degree of refining necessary to
produce the end product or in the addition of alloying
metals in the very last steps of the process (see Section
III). Therefore, a single category for brass and bronze
ingot producers and producers of refined copper is
supported.
Cathode copper, produced by electrolytic refining, is a
product of only the producer of refined copper and not of
the producer of brass and bronze ingot and, thus, was
considered as a basis for Subcategorization. Only one of
the eight copper refiners produced cathode copper, while all
eight, including the electrolytic refiner, produced fire
refined copper. Moreover, the company that produces cathode
copper produce their anodes by fire refining low and
intermediate grade scrap. The refining technique differs
from brass and bronze ingot production only in the extent of
refining and the possibility of byproduct recovery (i.e.,
Niscm, CuS
-------
928 gal/ton, while refined copper producers use an average
of 3,828 gal/ton. Water uses specific to the companies
studied in each product line of the industry are given in
Table 6. There are, however, plants producing copper that
use less water than some of the plants producing ingots.
Because of such variations in water use for each product
line and because these figures are not related to waste
water discharge (since the process water is recycled to
widely varying degrees), subcategorization based on water
usage is not practical.
These considerations of the products of the industry, when
related to processes used to manufacture them, support a
single category for establishments producing brass and
bronze ingots, those producing various grades of fire
refined copper, those producing electrolytically refined
copper products, and those producing a combination of these
products.
Processes. The main processes for converting scrap to
copper or copper-base alloys are (1) presmelting scrap
preparation, (2) charging and melting the scrap, (3)
refining the melt, and (4) pouring and casting end product
shapes. After analyzing and comparing the differences and
similarities of process waste water streams generated by
these operations, it was found that no differences exist
which are significant enough to warrant subcategorization.
Scrap preparation procedures employed on solids are common
to the industry. Residue scrap (primarily copper-rich slag)
is wet milled and classified to recover metal value by six
of the seventeen brass and bronze smelters in the entire
industry which process residues (thirty-five percent). The
remainder use blast or cupola furnaces for metal recovery.
All of the copper smelters employ melting for metal recovery
from residues. The fact that no smelter processes residues
alone but also processes solids by methods common to the
industry, supports establishment of a single category.
Methods used in charging and in the melting of the scrap
metal are common to the industry. Methods of pouring and
casting of the end product are also common to the industry.
Both process aspects support the establishment of a single
category.
In the refining process, the manufacture of secondary brass
and bronze ingots from scrap and residues usually stops
short of the extensive refining necessary to recover pure
copper from the same raw material. The refining that is
done in the brass and bronze segment of the industry is
50
-------
chemically and metallurgically identical to that done in
fire refining in the copper segment of the industry, and
similar types of pollutants will end up in the waste water.
Therefore, the differences in the extent of fire refining d
not warrant subcategorization and do support th^
establishment of a single category.
The waste water generated by the electrolytic process is
relatively small in volume, but was found to be
significantly different in character from other streams
produced by the secondary copper industry. The existence of
this process was thus considered as a possible basis for
subcategorization. The waste stream is generated as a bleed
stream taken from the recirculating electrolyte to prevent
buildup of metals impurities in the electrolyte. This bleed
stream is often subsequently mixed with cathode washwater.
As part of the process, copper is usually stripped from the
stream by iron cementation or electrowinning. Extremely
high levels of metals were found in this waste stream. One
electrolytic refiner produces nickel sulfate from the stream
with barometric condensers; another sells its purge to a
precious metals recovery facility. Most importantly,
however, it was found that this waste stream can be
effectively treated with pH adjustment and settle
technology, which is equally effective on other waste
streams generated by secondary copper smelters. For this
reason, therefore, the existence of an electrolytic refining
process at a plant is not considered to be a basis for
subcategorization.
Plant Age. The average age of all secondary copper plants
in the industry (including direct dischargers) is estimated
to be about 35 years. The oldest of the brass and bronze
ingot plants has been in existence for 78 years, while the
newest plant has been in operation for 8 years (average age
is 36 years). The oldest and newest plants in the refined
copper segment have been operating for 70 and 6 years,
respectively (average age is 34 years). From the study,
there appears to be no connection between either the age of
the plant and the character of the waste water or any
ability to treat waste water. Some of the oldest plants
have updated facilities for production and have retrofitted
waste water treatment facilities.
Air Pollution Control Methods. Fifty-three percent of the
plants discharging to POTW use dry air pollution control
systems, primarily baghouses. Thirty-five percent are
employing wet air pollution control systems, primarily high
energy scrubbers. Two plants apparently do not control air
emissions.
51
-------
The raw waste water generated by a plant using wet scrubbers
would be expected to have different characteristics than one
not employing a wet air pollution control system. in
practice, recycle of scrubber water is employed to assure
recovery of the metal oxides, and such plants should be able
to meet recommended pretreatment standards. Therefore,
establishment of a separate category for facilities
employing wet air pollution control systems is not
warranted.
Plant Location. Secondary copper smelters are located close
to their supply of raw material. Thus, most of them are
located within, or bordering on, large urban areas. New
scrap originates from manufacturing plants located within
the large population centers. Large amounts of old scrap
also originate from the same population centers.
In those cases where there is limited land available, these
pretreatment standards will entail additional considerations
in the assessment of the economic impact of the recommended
pretreatment technology. However, there exist operating
plants in such urban areas where the recommended control and
treatment technologies have been implemented, in view of
demonstrated achievement of the recommended limitations by
some plants in urban locations, the industry is considered
as a single subcategory on the basis of geographic location.
52
-------
SECTION V
WASTE CHARACTERIZATION
Introduction
The sources of wastewater within the segment of the
secondary copper industry discharging to POTW are set forth
in this section. The kinds, concentrations and loadings of
raw wastewater constituents are identified and compared to
those of direct dischargers.
Sources of Wastewater
The sources of wastewater in the segment of the secondary
copper industry discharging to POTW are nearly the same as
sources discharging directly and sources that have
eliminated process water discharges. The one notable
difference is that no POTW dischargers have been identified
which perform slag milling and classification. Sources of
wastewater include:
Wet scrubbing of air emissions
Metal cooling (ingot, anode, shot, billet casting)
Slag granulation
Electrolytic refining
Equipment cooling (non-contact).
A composite flow diagram of water use in these processes in
Figure 3. In a specific plant, waste water may not be
generated in all of these processes. For example, waste
water from electrolytic cells is generated by only one
plant. Mixing of waste water streams before treatment or
discharge is practiced by many of the plants. A summary of
the waste water disposal techniques practiced by the
industry is given in Table 8. In many cases, storm runoff
water is also collected and discharged after mixing with
process waste waters.
Characteristics of Waste Water Generated
by the Secondary Copper Industry
The- characteristics of waste water generated by the above
operations is given for secondary copper plants which
discharge to POTW. This information was obtained directly
from companies and by contract sampling teams. Information
developed and presented in the secondary copper effluent
limitations guidelines development document (Ref. 1) was
also considered. These data, along with flow and production
53
-------
Water Source
| POTABLE .
TREATMENT '
I -, 1
T.
I SANITARY I
I PRIMARY |
I AND
• SECONDARY '
' TREATMENT I
I- _ T __ I
Ul
SPRAY
AND/OR
QUENCH
COOLING
OF
MOLTEN
HETAL
?
1
EQUIPHENT
AND
NON-
CONTACT
COOLING
OF
MOLTEN
METAL
SLAG
GRANULATION
SLAG
MILLING
AND
CLASSIFYING
MELTING AND REFINING
FURNACE EXHAUST
SCRUBBING
pH Adjustment
NaOH, Ca(Oll) ,NII
PRIMARY SOLIDS REMOVAL
SETTLERS AND THICKENERS
Various Combinations of Wascevaters ©,©,©, and ©
• re Cooled and Discharged Into Settling Tanks or Ponds
from Which They May Be Discharged or Reclrculated.On
Occasions @,
-------
TABLE 8. Waste Water Disposal Practices of Secondary Copper
and Brass and Bronze Smelters (Inudstry-wide)
Waste Water Number of Plants (Percentage)
Disposition Process Non-Process
No discharge reported 17 (37) 15 (33)
Sanitary sewers 17 (37) 19 (41)
Surface waters H (24) 11 (24)
Undetermined 1 (2) i (2)
Total 46 46
55
-------
or capacity information for each plant, were used to
characterize the effluents for each plant for which data
were available.
Waste water from most operations received some treatment
before being discharged, usually in the form of coarse
settling. pH adjustment was rarely observed at indirect
dischargers. Water from ingot quenching, shot manufacturing
and slag granulation was always settled to some degree as a
result of the fact that the above operations take place in
quench pits. Water from ingot cooling sprays and water from
wet air pollution control devices was found to always be
treated to remove the bulk of suspended solids. Waste water
from electrolytic cells was treated with iron powder to
remove the copper before being released. Non-contact
cooling water was normally cooled in a tower before being
recycled or released to a mixed stream. Recycle of process
waste waters was practiced to varying degrees at each of
these operations.
After preliminary treatment, streams were discharged to city
sewers or recycled with some discharge. Some plants
recirculated all of the water with only periodic discharges.
Still other plants recycled with a continuous discharge, and
others discharged all of their waste water on a once-through
basis.
A summary of water use and discharge flow rates for the
various processes found at indirect dischargers is presented
in Table 9. This data is discussed in detail in each of the
sections that follow.
Waste Water from Air Pollution Control
Fifteen of the seventeen smelters of secondary brass and
bronze and secondary copper employ some form of air
pollution control. The air cleaning equipment may be either
baghouse filters (dry or water spray cooled), which produce
no waste water, or it may be high energy venturi type
scrubbers, which require large quantities of water for their
operation. Sometimes, both types are employed at the same
facility. These two types of equipment are used in
conjunction with most melting and refining operations. For
hydrocarbon type exhausts, such as the emissions from driers
used to remove oil from turnings, afterburners are used to
control the smoke and hydrocarbon content. Electrostatic
precipitators are also used by a small percentage of the
smelters in conjunction with wet and dry systems.
56
-------
TABLE 9 . PROCESS WATER USE AND DISCHARGE FLOW RATES
PLANT
CODE
1
2
3
4'
S
8
9
10
11
12
13
14
15
16
17
18
19
METAL COOLING
DISCHARGE
gal/day
1.000
900 gal/year
100
ANODE
288,000
BILLET
24,000
300
150
4OO
106,000"
•
500 FOR 5
days/mo.
760.00O" FOR
10 days/mo.
2,800 sal/week
2.400
1,500 gal EVERY
3-4 mos.
1OO
7,000 gal TWICE
YEARLY
29,000
3,000"
gal/ton
50
0.2
100
1614
134
21
4.3
21
1,700
100
101,300
44
190
4.7
806
500
USE
gal/day
76,500
750
125.000
760,000 FOR
10 days/mo.
9.000
gal/ton
5,500
21
2,000
101.300
95
EMISSIONS SCRUBBING
DISCHARGE
gal/day
.
*
»
ANODE
144,000
BILLET
72,000
-
*
*
4,000
gal/ton
806
402
1,100
INFREQUENT OVERFLOW
*
*
»
*
2OO
*
500/wMk
6.1
17
USE
gal/day
5.000
gal/ton
1.300
ELECTROLYSIS
DISCHARGE
gal/day
*
*
*
37.000
*
.
.
*
*
*
*
*
*
•
*
«
gal/ton
206
USE
gal/day
gal/ton
SLAG GRANULATION
DISCHARGE
gal/day
.
*
*
*
•
*
*
54.000
*
•
*
*
*
•
*
•
gal/ton
870
USE
gal/day
78.400
gal/ton
1,300
•NO FLOW RATE APPLICABLE BECAUSE OF THE FOLLOWING POSSIBILITIES: (a) PROCESS NOT USED
-------
Of seventeen secondary copper plants which discharge process
wastewater to POTW, nine use dry emissions control and two
have no emissions control. Three plants use only w=t
scrubbers for emissions control and three use both wet and
dry emissions controls. in addition, at least two of th<-
ten plants employing dry emissions control devices use water
sprays to cool the exhaust gases prior to entering the
baghouse or ESP. A small effluent stream (200 gpd) is
generated by this operation at one plant, while all such
cooling water is evaporated at the other.
Of the six plants using wet scrubbers for emissions
controls, five recycle most scrubwater with minor bleedoffs
to POTW. The other plant uses dry emissions control on all
furnaces except one. The water at this scrubber
recalculates at 150,000 gpd, and approximately 4,000 gpd is
bled off in a continuous stream and discharged to a POTW.
Dusts, smoke, and fumes are removed from exhausts from the
following industry operations:
Cupola or blast furnace melting,
Reverberatory, electric, rotary,
or crucible furnace operation,
Converter operation.
Pouring and casting.
Cupola and blast furnace operations, used to recover metal
values from copper (or brass and bronze) rich slags or
residues, produce large quantities of particulate matter
from dusty charge materials, such as fine slags, fine fluxes
of silica sand, limestone, or fluorspar, and coke ash or
coke breeze, as well as metal oxide fumes. Some smoke is
also produced from the combustion of coke and organic wastes
in the charge materials. Metal oxide fumes are produced
from zinc, lead, and other volatile metal impurities, if
they are present in the charge.
Reverberatory, electric, and rotary furnaces produce some
smoke, particularly if oil-fired or if the charge is not
pretreated to remove organic wastes. Fumes of metal oxides
are produced when the molten metal is blown with air or
oxygen to remove metallic impurities, or when green wooden
poles are inserted into the bath to deoxidize the heat.
Dust will be produced during the charging of fine slags or
fine flux materials. Borax is almost always present as one
of the flux constituents.
Exhausts from converters contain metal oxides of all of the
metals present, including some copper oxide and the oxides
58
-------
of sulfur, phosphorus, or other nonmetals that were present
in the original melt. When wet scrubbing is used, these
constituents will be contained in the water as suspended or
dissolved solids. A considerable amount of zinc oxide and
some lead oxide fumes are formed during the pouring of
molten brass or bronze alloys that contain these volatile
metals. Their fume is generally collected along with the
combustion exhaust gases and directed to the air cleaning
equipment. Casting of molten refined copper does not
usually produce metal oxide fumes, since zinc or lead are
not present or are present in such lew concentrations in
partially refined copper (anode or blister copper) that very
low partial pressures are exerted.
Wet air scrubbers remove from 90 to 99 percent of the
entrained solids. Most of these solids are removed from the
scrubber water by means of settling pits, and the clarified
water is recycled. pH adjustment may te necessary. A bleed
stream from this recirculating system may be pumped to a
pond where it is mixed with other process waters or it may
be discharged directly to a POTW.
The sludge collected from air scrubbing operations during
brass and bronze smelting will contain over 50 percent zinc
(as zinc oxide) and one to two percent lead as its oxide.
The sludge recovered from wet air scrubbing during the
refining of copper by blowing will contain up to four
percent copper as oxide and varying amounts of zinc and
lead, depending on the grade of scrap that entered the melt.
Waste water discharged from settling ponds or tanks would be
expected to contain suspended solids of about the same
composition, on a dry basis, as the sludge. In addition,
the waste water would contain most of the soluble
constituents originally in the feed water plus borax, metal
borates, lime, and soda ash when these materials are used as
furnace fluxes.
Characteristics and loadings of emissions scrubwater
discharged to POTW from phosphor copper furnaces at two
plants and the anode and billet furnaces of an electrolytic
copper plant are given in Tables 10 and 11. In addition,
characteristics of emissions scrubwater at two secondary
copper facilities which do not discharge to POTW appear in
Table 12. With the exception of the phosphor copper furnace
scrubwater, the pH's of raw scrubwater from all of these
furnaces was in the range of 7-8. The low pH of scrubwater
from the phosphor copper furnace is believed attributable to
the formation of phosphoric acid in the scrubwater. It
should be noted that the suspended solids content of the
effluent measured at indirect dischargers was appreciably
59
-------
TABLE 10. CHARACTERISTICS OF RAW WASTEWATER FROM EMISSIONS SCRUBBING -
POTW DISCHARGERS oonuooiwu
PARAMETER
PH
TSS
Oil and Grease
Pb
Cu
Cr
Ni
Zn
Cd
Sb
Hg
B
PLANT 11
Phosphor Copper Furnace'1'
Scrubber Water
Concentration
(mg/l)
1.60*
19
3
9.43
19.7
0.07
0.06
30.6
0.133
0.2
< 0.0005
<0.02
Loading
kg/MT
0.080
0.01
0.040
0.083
0.0003
0.0003
0.13
0.00056
0.0008
<0.000002
< 0.00008
Ib/ton
0.16
0.02
0.080
0.17
0.0005
0.0005
0.26
0.0011
0.002
< 0.000004
< 0.0002
PLANTS (Cathode Copper)
Anode Furnace *2'
Scrubber Water
Concentration
(mg/l)
7.10*
1050
<1
387
138
0.52
2.51
167
5.77
2.1
0.151
2.30
Loading
kg/MT
4.0
<0.004
1.5
0.52
0.0020
0.0095
0.63
0.022
0.0080
0.00057
0.0087
Ib/ton
8.0
<0.008
2.9
1.0
0.0040
0.019
1.3
0.044
0.016
0.0011
0.017
(1)
(2)
'AVERAGE OF 8 SAMPLES OVER 2 DAY PERIOD. Hg DATA IS AVERAGE OF 4
COLLECTED OVER 2 DAY PERIOD.
SAMPLES TAKEN BEFORE SETTLING OF COARSE SOLIDS.
AVERAGE OF 7 SAMPLES OVER 2 DAY PERIOD
SAMPLES
* pH UNITS
60
-------
TABLE 11. CHARACTERISTICS OF RAW WASTEWATER FROM
EMISSIONS SCRUBBING - POTW DISCHARGERS
PARAMETER
pH
TSS
Oil and Grease
Pb
Cu
Cr
Ni
Zn
Cd
Sb
Hg
B
PLANT 5(A)
BILLET FURNACE SCRUBBER WATER
CONCENTRATION
(mg/l)
6.90»
116
-
6.62
72.0
0.24
0.04
5.08
0.23
102
0.032
0.73
WASTE LOAD
kg/MT
-
0.20
-
0.011
0.12
0.00041
0.00007
0.0086
0.0004
0.017
0.000054
0.0012
Ib/short ton
—
0.38
—
0.022
0.24
0.00079
0.0001
0.017
0.0008
0.034
0.00010
0.0024
PLANT 19(B)
PHOSPHOR-COPPER FURNACE SCRUBBER WATER
CONCENTRATION
(mg/l)
1.70*
15
1
0.62
14.7
0.085
0.85
1.64
0.045
0.75
-
0.03
WASTE LOAD
kg/MT
-
0.0010
0.00007
0.000043
0.0010
0.0000060
0.000060
0.00011
0.0000032
0.000053
-
0.000002
Ib/short ton
-
0.0021
0.0001
0.000087
0.0021
0.000012
0.00012
0.00023
0.0000063
0.00011
-
0.000004
(A) SAMPLE TAKEN PRIOR TO SETTLING OF COARSE SOLIDS. 24 hr. COMPOSITE
(B) GRAB SAMPLE
*pH UNITS
-------
TABLE 12. CHARACTER OP WASTE WATER FROM AIR SCRUBBER AFTER
THICKENER (Before centrifuge and settling) —DIRECT DISCHARGERS
Plant V (»)
Product
kkg/day
Con/day
Water flow,
I/day
Constituent
Alkalinity
COD
Solids, Total
Solids, Dis3.
Solids, Susp.
TOC
Phosphorus
Cyanide
Antbnony
Arsenic
Boron
Cadmium
Copper
Iron
Lead
Manganese
Mercury
Nickel
Zinc
Oil and Grease
PH
Intake
Cone. ,
mg/1
Alloy
9.7
10.7
22,800(c;
79
--
306
5
301
0.01
0.06
D.I
<0.02
0.002
<0.05
0.06
0.21
0.11
0.20
<0.001
<0.1
<0.1
--
7.2
Cone . ,
mg/1
19,000
44
295
6669
2465
4201
530
<0.01
0.06
3.9
1.3
5.7
3
280
20.7
1802
2.1
0.005
3
1517
164
7.1
Discharge
Loading
kg/kkg
NLC
0.578
12.344
4.817
7.521
1.038
NLC
0
0.0076
0.0026
0.011
0.006
0.548
0.040
3.565
0.004
1 x 10"6
0.006
2.971
0.321
(lb/ton)
(NLC/
(1.156)
(24.688)
(9.634)
(15.042)
(2 .076)
(' NLC'
0
(0.0152)
(0.0052)
(0.022;
10.0121
(1.096)
(0.080)
(7.130)
(0.008)
(2 x 10'6)
(0.012)
(5.942)
(0.642J
Intake
Cone. ,
mg/1
Copper
45.3
50
7,086,000b>
Cone . ,
mg/1
5,669,000
90
15.2
2310
277
2033
--
0.018
O.C03
0.174
<0.001
4.70
2.158
0.039
<0.009
0.235
0.111
<.00059
0.021
9.922
<1
7.62
Disuhai'gt:
Loading
kg/kkg
NLC
ULC
38.19
24.65
61.85
--
;ac
NLC
NLC
0
0.203
0.287
NLC
..
HLC
NLC
1 x 10-5
NLC
1.008
0
(Ib/ton)
'NT.C;
(NT.C;
'176.J3;
(49.10)
(12",.,.))
",<<••)
;'T">}
(iiic;
0
(0,406)
fO. 5/4)
' I.-LC;
..
fNLd
(NLC)
(2 x io-5)
(NLC)
(2 .016)
0
(a) Average of 3 days sampling; two samples taken each day were composited Into dally samples.
(b) After quench of exhaust gas but before venturi scrubber.
(c) Estimated to be 20 percent more than discharge.
(d) NLC = no loading calculable because discharge load is less than intake.
-------
less than that measured from direct dischargers, which can
be attributed to the fact that some settling of coarse
solids occurred prior to the sampling point of the
scrubwater at the indirect dischargers. Emissions
scrubwater from all sources showed appreciable
concentrations of the metals lead, copper, nickel, zinc,
antimony, and of boron.
The net effect of subsequent solids removal treatment by
settling after pH adjustment with caustic or lime has been
determined and is described in section VII.
Process water use and discharge flow rates for wet air
pollution scrubbing operations at plants discharging to POTW
are shown in Table 9. Discharge rates vary from 216,000
gallons per day to 500 gallons per week, and loadings on a
production basis vary from'1100 gal/ton to 6.1 gal/ton. The
figures presented for production loadings are presented for
illustration only, and must be interpreted only with
considerable caution since the degree of use of wet
scrubbers in a plant is not a function of the total
production of a plant. The great range of discharge rates
observed appears to be largely due to differences in the
volumes of exhaust gases scrubbed, and due to the
differences in the manner of operation of scrubbers at each
plant. Due to the wide variation of flow rates observed, it
is not felt that flows from this operation can be generally
characterized for this segment of the industry.
The large volumes of water necessary to operate wet air
scrubbers makes recirculation of the water, after the bulk
of solids have been removed, an economic necessity. The
settled sludge consists mostly of a poor grade of zinc oxide
and is sold by most smelters. Some form of settling is
always used to aid cooling when the volumes of water are
large. The recirculation of water tends to concentrate
dissolved solids. This has caused a seasonal problem at one
direct discharger (Plant W, Table 4), but other direct
dischargers recirculate all of their scrubber water with no
apparent problems. All indirect dischargers recirculate
most of their scrubber water with no reported problems.
Waste Water from Metal Cooling
The use of water for metal cooling is the most frequent use
of water in that segment of the industry which discharges to
POTW. All seventeen plants which discharge to POTW use
water for metal cooling. The predominant practice of these
plants is to recycle quench water with continuous or
periodic bleeds to POTW.
63
-------
The methods used for contact metal cooling at those plants
that discharge to POTW do not differ from those used at
direct dischargers. In the case of ingots, anodes and
billets, the molten metal is solidified by spray cooling or
partial immersion of the mold and then quenched in tanks.
Finished refined copper shapes are usually prepared by
cooling the molten metal by non-contac cooling techniques
and then quenching the solidified metal with clean water
(usually municipal) to limit staining of the metal surface.
Shot is manufactured by directing a small stream of molten
copper directly into a quench pit.
Smooth brass and bronze ingots must cool slowly in the mold
under a layer of charcoal to produce the smooth surface
requested by certain customers. Ingot mold lines are quite
long for the production of smooth ingots. In a typical
operation, the ingots are permitted to air cool in the mold
during the first portion of the conveyer travel; the bottom
of the ingot mold is immersed in a tank of water during the
second portion of the conveyer travel; and, finally, the
solidified ingot is discharged into a quench tank of water.
Part of the charcoal burns during the ingot travel on the
conveyer. The unburned charcoal and charcoal ash all end up
in the cooling water. This charcoal and sludge are
periodically cleaned out. of the quenching tanks, settling
tanks, and ponds or cooling towers. The water from the
settling tank may be recirculated or discharged.
In addition to the charcoal and charcoal ash, the water
pollutants associated with direct metal cooling are small
amounts of metal oxides from the ingot surface, refractory
mold wash (calcium phosphate), and dust from the smelter
floor. Charcoal is not used when casting copper anodes, but
a calcium phosphate mold wash is often employed which ends
up in the waste water. Oil and grease, used to lubricate
the automated casting and conveying system, appears in
cooling waste water.
Contact cooling waste water is normally settled and recycled
after cooling, generally as a mixed stream. It may be
discharged after settling. Contact cooling water employed
to quench cool the finished refined copper shapes is
sometimes recycled, sometimes after passing through heat
exchangers or through a cooling tower.
The generation of cooling waste water is intermittent during
daily operations at a plant. The period of operation will
vary with the capacity of the mold line and the capacity of
furnaces containing the finished metal. In some operations,
casting may require only 2 tc 2.5 hours, while in large
64
-------
installations, casting can be continuous for an 8 to 10-hour
period.
Process water use and discharge flow rates for metal cooling
operations at plants discharging to POTW are presented in
Table 9. Discharge rates vary from 760,000 gallons per day
to 900 gallons per year, and loadings on a production basis
vary from 101,300 gal/ton to 0.2 gal/ton. This tremendous
range of water usage rates reflects the widely varying
practices of plant operators in cooling molten metal, which
range from continuously purging quench pits to emptying
quench pits only occasionally for cleaning, adding make-up
water only as needed to offset losses from evaporation. Due
to the extreme variation of flow rates observed, it is not
felt that flows from this operation can be characterized for
this segment of the industry.
Contact cooling water streams were sampled at five plants
which discharge to POTW to determine the characteristics and
loadings of the untreated waste water. This data appears in
Tables 13, 14 and 15. It should be noted that some settling
occurred prior to sampling in each case, because the process
entails the use of a pit for the quenching operation, or in
the case of the billet casting cooling water from plant 5,
some coarse settling had occurred in cooling tower wells
prior to the sampling point. In addition, the
characteristics and loadings of raw waste streams from metal
cooling and quenching operations at a direct discharger is
presented in Table 16.
As would be expected, the quality of raw wastewater from
metal cooling operations at plants which are indirect
dischargers is similar to that sampled from direct
dischargers. The only appreciable and consistent difference
was the very low concentration of oil and grease found in
metal cooling water from POTW dischargers. As with
emissions scrubwaters, constituents found in highest
concentrations were the metals zinc, lead, copper, and
antimony. Generally, however, the concentrations of these
constituents are less than those found in scrubwater
effluents.
Waste Water from Slag Granulation
Although five direct dischargers quench and granulate slags,
only one plant (Plant 11) discharging to a POTW conducts
slag quenching and granulation operations. This operation
at this plant is conducted periodically rather than
continuously. At the time slag is granulated 54,000 GPD
65
-------
TABLE 13. CHARACTERISTICS OF RAW WASTEWATER FROM METAL COOLING -
DISCHARGES TO POTW
PARAMETER
pH
TSS
OH MKlGrMH
Pb
Cu
Cr
Ni
Zn
Cd
Sb
Hgf
B
PLANT 18 (BRASS AND BRONZE)
Oiocod
(ing/I)
8.75'
16
<1
0.88
1.03
<0.02
0.02
2M
<0.01
<0.2
-
<0.02
PH Onflow I1'
kg/MT
0.013
<0.0008
OJ1OD70
O.OOOB2
^0.00002
O.OOO02
OJO023
•OunooM
-------
TABLE 14. CHEMICAL CHARACTERISTICS OF RAW WASTEWATER FROM PHOSPHOR-COPPER
SHOTTING - POTW DISCHARGERS
PARAMETER
pH
TSS
Oil and Grease
Pb
Cu
Cr
Ni
Zn
Cd
Sb
B
Hg
PLANT 1KA)
CONCENTRATION
(mg/'l
3.10*
23
<1
0.33
0.40
0.029
0.026
0.71
0.006
<0.1
<0.02
< 0.0002
LOADING
kg/MT
-
0.019
<0.0008
0.00027
0.00033
0.000024
0.000022
0.00059
0.000005
< 0.00008
< 0.00002
< 0.0000002
Ib/ton
-
0.039
<0.002
0.00056
0.00066
0.000049
0.000044
0.0012
0.00001
< 0.0002
< 0.00003
< 0.0000003
PLANT 14
-------
TABLE 15. CHARACTERISTICS OF RAW WASTEWATER FROM
SHOT QUENCHING - POTW DISCHARGER PLANT 3{1>
PARAMETER
PH
TSS
Oil and Grease
Pb
Cu
Cr
Ni
Zn
Cd
Sb
Hg
B
CONCENTRATION
(mg/l)
8.30*
14
<1
3.76
1.87
0.10
0.02
1.56
0.053
8.0
0.0003
1.38
LOADING
kg/MT
—
0.0062
< 0.0004
0.0017
0.00082
0.000044
0.000009
0.00069
0.000023
0.0035
0.0000001
0.00061
Ib/ton
_
0.012
< 0.0009
0.0033
0.0016
0.000088
0.00002
0.0014
0.000047
0.0070
0.0000003
0.0012
(1'AVERAGE OF 3 GRAB SAMPLES
*pH UNITS
-------
TABLE 16 .CHARACTER CF WASTE WATER FROM MDLTEN METAL COOLDC AND QUENCHING DIRECT DISCHARGER
O.
Product
kkft/dav
(ton/day)
Flow,
1/dav
(gal/day)
Constituent
Alkalinity
COD
Solids lot.il
Solids, Riss.
Solids, Susp.
TOC
Phosphorus
Cyanide
Antimony
Arsenic
Boron
Cadminum
Chromium
Copper
Iron
Lead
Manganese
Mercury
Nickel
Zinc
Oil and Cri'.ise
PH
(a) Includes some equipment cooling in discharge.
(b) NLC = no loading calculable.
(c) Cross loading.
(d) Net loading.
(e) Casting time estimated ,it 4 hours.
(f) NF - not found.
Intake
Cone . ,
mg/1
170
23.2
1294
64
1231
0.029
0.005
0.142
:0.001
2.46
0.111
0.098
<0.005
0.297
0.325
<0.0004
0.024
1.492
<1
8.3
E(Net)
Discharge
Cone., Loading
. _ _.
rag/1 kg/kkg (Wton)
Copper
45.3
(50)
3,000,000(e>
(792 ,000)
182 0.795 (1.
11.2 NLC
1238 NLC
31 NLC
1208 NLC
0.023 NLC
0.005 NLC
0.126 NLC
<0.001 NLC
2.35 NLC
0.098 NLC
0.069 NLC
<0.007 NLC
0.223 NLC
0.372 0.003 (0.
<0.0002 NLC
0.019 NLC
0.821 NLC
<1 0
8.3
59)
006)
Source: EPA sampling excursion (1973)
-------
are discharged to a POTW and another 78,400 GPD are recycled
after passing through a cooling tower.
At secondary copper smelters that discharge to POTW, as well
as all others, slag covers on reverberatory or rotary
furnaces are generally raked-off before the furnace is
tapped. This slag will contain a variety of materials,
including slags and fluxes that have been added, rasorite (a
borax flux), soda ash, lime, silica or glass, sand, and
about 10 to 30 percent copper or alloy. This copper content
can be recovered, and this is done either by melting down
the entire slag in a cupola or blast furnace or by milling
and classifying the slags into a waste gangue material and a
copper-rich concentrate.
When cupolas or blast furnaces are employed to recover the
copper values from reverberatory or rotary furnace slags,
the bulk of the copper-rich slag is normally screened, and
the fine slag is pelletized. The coarse chunks and the
pellets of slag are charged into the cupola or blast furnace
along with other scrap copper, coke, and fluxes. The charge
is melted and two products are tapped, a copper alloy (black
copper or cupola melt) and a waste or depleted slag that
contains about one to two percent copper. The waste slag is
granulated by directing it into a quench pit while still in
its molten state. The granulated slag is raked from the
bottom of the pit and sent to the slag pile and the quench
water is sent to a cooling tower and recirculated. A bleed
from this recirculating stream is sent to a POTW.
An alternative slag treatment method consists of grinding
the slag and separating the copper values from the bulk of
the slag by milling and classification methods. Although
slag milling and classification is practiced by five direct
dischargers, no plants discharging to POTW recover copper
values in this manner.
Table 17 presents the characteristics of raw wastewater from
slag granulation operations at one POTW discharger, Plant
11. Table 18 presents information obtained from the slag
granulation operation of one direct discharger (Plant E).
Table 18 also presents raw waste stream data from slag
milling and classification operations at three direct
dischargers. This data is expected to be generally
comparable to the characteristics of wastewater from slag
granulation once this water has cooled to ambient
conditions, since materials from nearly identical sources
are being treated in either case.
70
-------
TABLE 17. CHARACTERISTICS OF RAW WASTEWATER FROM
SLAG GRANULATION - POTW DISCHARGER PLANT 11*
PARAMETER
PH
TSS
Oil and Grease
Pb
Cu
Cr
Ni
Zn
Cd
Sb
B
Hg
CONCENTRATION
(mg/l)
8.55* •
30
<1
3.35
0.59
0.026
0.02
11.3
0.008
<0.1
0.37
< 0.0002
LOADING
kg/MT
-
0.063
< 0.002
0.0070
0.0012
0.000055
0.00004
0.024
0.00002
< 0.0002
0.00078
< 0.0000004
Ib/ton
-
0.13
< 0.004
0.014
0.0025
0.00011
0.00008
0.047
0.00003
< 0.0004
0.0016
< 0.0000008
* AVERAGE OF 4 SAMPLES
•»pH UNITS
71
-------
TABLE 1 8 . CHARACTER OF UMTS WATER FRCM SLAG QUENCHING AND GRANULATION
OR SLAG MILLING AFTER SETTLING DIRECT DISCHARGERS
(Gross and/or Net Loading)
E (Met) (a)
Intake
Cone . ,
mg/1
Product
kkg/day
(ton/ day)
Water flow
I/day
(gal/day)
Constituent
Alkalinity 170
COD 23.2
Sollds.lot.il 1294
Solids, dlss. 64
Solids, susp. 1231
TOC
Phosphorus 0.029
Cyanide 0.005
Antimony 0.142
Arsenic X).001
Boron 2 ,46
Cadmium 0.111
Copper 0.098
Chromium
Iron '0.005
Lead 0.297
Manganese 0.325
Mercury D.0004
Nickel 0.024
Zinc 1.492
Oil and Grease 1
pH
(a) Slag granulation.
(b) Slag milling.
(c) Estimated time for
(d) NF = not found.
Cone . ,
mg/1
Discharge
! o.ndlng
kR/kkf! (Ib/ton)
CiO)
3,000,000(c>
(792,000)
190
25.3
1620
336
1284
0.031
0.004
0.111
0.001
2.60
0.067
0.071
T1.007
0.192
0.399
T3.0003
0.030
0.622
granulation
1.325 (2.650)
0.139 (0.278)
21.589 (43.18)
18.013 (36.03)
3.510 (7.020)
0.0001 (0.0002)
NLC
NLC
NLC
0.001 (0.001)
NLC
NLC
NLC
NLC
0.0005 (0.001)
NLC
NLC
NLC
NLC
6 hr/day.
Company by Code
GJ (Gross) (b)
Intake Discharge
Cone., Cone., Loading
mg/1 mg/1 kg/kkg (Ib/ton)
Intake
Cone . ,
mg/1
Alloy
108
(119)
545,400
(144,100)
2965
3900
630
- „<«
0.11
19.78
0.120
13.0
23.0
0.35
80.35
9.8
14.976
19.695
3.182
--
0.0006
0.100
0.001
0.066
0.116
0.002
0.631
(29.95)
(39.39)
(6.364)
(0.0012)
(0.20)
(0.002)
(0.132)
(0.232)
(0.004)
(1.262)
71.33
18,333
421.3
387.67
33.67
63.3
0.293
0.053
<0.02
0.667
0.067
12
1.833
5.333
0.467
<0.001
0.133
6.0
11.0
7.4
Discharge
Cone. , Loading
mg/1 kg/kkg (Ib/ton)
Alloy
9.7
(10.7)
72 .670
(19,200)
104.67
22.67
6456
2953.7
3502.3
268.67
0.403
0.163
2.867
<0.02
6.0
1.683
1250
163.667
916.67
43.33
0.012
18.0
983.33
23.333
8.53
0.250
0.032
45.210
19.224
25.986
1.539
0.001
0.001
0.021
NLC
0.040
0.012
9.275
1.212
6.835
0.321
0.001
0.134
7.322
0.092
(0.50)
(0.064)
(90.42)
(38.45)
(51.97)
(3.078)
(0.002)
(0.001)
(0.042)
(0.080)
(0.012)
(18.55)
(2 .424)
(13.67)
(0.642)
(0.002)
(0.268)
(14.64)
(0.184)
•—
( H«t) 0>)
Intake Discharge
Cone., Cone., Loading
mg/1 mg/1 Tcg/kkg (Ib/ton)
Alloy
43.5
(48)
662,400 617,000
(175,000) (163,000)
685 733 0.681
1,754 1,852 1.39
21,405 22,980 326
1.0 1.0 NLC
0.10 0.11 0.00014
13 14 0.0142
0.9 1.0 0.0014
0.05 0.05 HLC
0.16 0.17 0.00014
0 0 HLC
9.35 9.55
(1.36)
(2.78)
(652)
(0.00028)
(0.0284)
(0.0028)
(0.00028)
— i^— __
(e) NLC = no loading calculable.
Source: Plants G and W, State Environmental Agencies;
Plants E and v, EPA sampling excursions (1973)
-------
Hydrolysis of the slags causes a pH of about 5.5. The other
characteristics of slag treatment waste water are high
levels of suspended solids and metals, particularly lead and
zinc.
Process water use and discharge flow rates for slag
granulation at the one plant discharging to a POTW which
performs this operation are presented in Table 9. These
rates can be characterized for this plant during slag
granulation operations, but it should be noted that slag
granulation operations take place only intermittently
throughout the year.
Waste Water from Electrolytic Cells
Electrolytic cells are used to refine anode copper into high
purity cathode copper. The anodes are cast in metal molds
from fire refined copper. The electrolyte solution consists
of demineralized makeup water, copper sulfate, and sulfuric
acid. Normally, the electrolyte solution is continuously
circulated through thickeners and filters to remove solids
and recycled back through the electrolytic cells. The cells
operate hot, so that some makeup water is required. The
makeup water normally comes from the boiler condensate in
the steam lines used to heat the cells. Most of the makeup
water is generally added during the daily washdown of salts
which accumulate at the tops of the cells through
evaporation.
The slimes periodically cleaned out of the cells are
filtered from the electrolyte and may be sold for the
recovery of precious metals and rare elements when present
in sufficient amounts. Otherwise, it is recycled to the
furnaces. Plant 5, the only electrolytic refiner
discharging to a POTW, sells its slimes for their precious
metal content.
Frequently, the concentration of copper in the electrolyte
solution builds to a level where the conductivity of the
solution decreases to less than the optimum range for good
electrical energy utilization. The amount of copper in the
electrolyte is then decreased by bleeding a small volume of
spent electrolyte, and replacing it with fresh makeup
electrolyte. The bleed stream is then stripped of copper
either by higher voltage electrolysis in a separate cell
(i.e., electrowinning), or the copper is removed by
cementation with iron.
Only one plant discharging to a PCTW employs electrolytic
refining processes. This plant strips copper from spent
73
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TABLE 19. CHARACTERISTICS OF SPENT WASTE ELECTROLYTE
AFTER COPPER RECLAMATION BY IRON CEMENTATION
PLANT 5 - POTW DISCHARGER
PARAMETER
PH
TSS
Oil and Grease
Pb
Cu
Cr
Ni
Zn
Cd
Sb
B
CONCENTRATION (1) (mg/l)
3.6*
91
<1
1.01
6.87
2.28
136
175
1.29
2.2
0.53
LOADING
kg/MT
0.12
< 0.001
0.0013
0.0089
0.0030
0.18
0.23
0.0017
0.0029
0.00069
Ib/ton
_
0.24
< 0.003
0.0026
0.018
0.0059
0.35
0.46
0.0034
0.0057
0.0014
<1> AVERAGE OF 2 SAMPLES - 24 HR. COMPOSITES
* pH UNITS
74
-------
electrolyte and discharges the barren solution to a POTW
without further treatment.
The spent electrolyte effluent stream was sampled and
analyzed after cementation, which is considered to be part
of the process. This data is presented in Table 19,
revealing a highly acidic waste stream containing high
concentrations of every metal analyzed. Process water use
and discharge flow rates for this operation at Plant 5 are
presented in Table 9.
Noncontact Cooling Water
Large amounts of water are used at times to cool doors and
frames of furnaces, to cool power transformers and furnace
coils or inductors in induction furnace melting, to cool
bearings, to externally cool the ducts of baghouses used in
air pollution control, and to cool the shells and burners of
blast furnace equipment. Non-contact cooling water is also
used to cool copper billets and cakes cast from metal
cathodes. Data from non-contact cooling water sources was
not collected from plants discharging to POTW, but data is
available from direct dischargers. Non-contact cooling
water from these plants is characterized in Table 20, and
must be considered, since it enters mixed water streams in
many plants. Cooling water is normally cooled in cooling
towers and recycled, with a bleed stream being discharged.
At Plant E, the water is a mixed stream and the pollutant
loadings were negative except for lead and zinc. The 009
and 010 pipe discharges of Plant R (Tables 21 and 22) also
illustrate the low levels of loadings in non-contact cooling
water.
Runof f Water
Metal oxide fumes from refining furnaces or ingot casting
operations escaping air emissions control will settle on the
ground or paved surface within the plant boundary and
surrounding watershed areas. During rainfall, the metal
oxides and other particulates may be collected at some
plants and carried to sanitary sewers as pollutants. Data
was not collected from indirect dischargers, but data is
available from one plant that discharges no process waste
water. The characteristics of a runoff discharge were
determined during sampling of this plant (Plant V), and
these are given in Table 23. Some copper, iron, manganese,
and zinc are apparently present in the water.
75
-------
TABLE 20.' GKTVJKttCriiK
-------
TABLE 21. CHARACTER OF WASTE WATER
FROM NONCONTACT COOLING
(PLANT R, PIPE 009)
Volume: 37,850 I/day (10,000 gal/day)
Operations: Noncontact cooling water, cooling tower blowdown
(cold side)
Production: 149.7 kkg/day (165 tons/day)
Constituent
Alkalinity
BOD, 5 -day
COD
Solids
Diss. Solids
Susp. Solids
Total Vol Solids
Nitrate (as N)
Kjeldahl Nitrogen
Ammonia (as N)
Phosphorus (as P)
Sulfate (as S)
Sulfide (as S)
Chloride
Fluoride
Aluminum
Antimony
Arsenic
Cadmium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Mercury
Nickel
Potassium
Silver
Sodium
Tin
Titanium
Zinc
Oil and Grease
Surfactants
PH
Temp (Win),C(F)
Temp (Sum),C(F)
Intake,
mg/1
15
0
19
90
58
14
44
1.75
1.54
0.05
0.02
0.6
0.1
14
1.16
20
0
0
0
7.5
0.010
0
0
0.40
0
5
0.050
0
0
0.35
0
25
0
0
0.100
4.1
0.60
6.85
14(58)
16(60)
Discharge,
mg/1
18
0
26
116
82
26
68
1.0
2.38
0.02
0.08
1.2
0.1
21
1.2
20
0
0
0
7.5
0.015
0
0.225
0.350
0.425
5
0.025
0.0005
0
0.35
0.005
25
0
0.010
0.065
3.9
0.62
6.85
23(73)
24(75)
Net Cone.,
mg/1
3
0
7
20
24
12
24
-0.75
0.84
-0.03
0.06
0.6
0
7
0.084
0
0
0
0
0
0.005
0
0.225
-0.05
0.425
0
-0.025
0.0005
0
0
0.005
0
0
0.010
-0.035
-0.2
0.02
Net
kg/kkg
0.00.08
NLC
0.0018
0.0051
0.006
0.003
0.006
NLC
0.0002
NLC
2X10 A
2xlO"4
NLC
0.0018
2xlO'5
NLC
NLC
NLC
NLC
NLC
1.3X10'6
NLC
5.7x10
NLC
0.0001
NLC
NLC
1.3xlO'7
NLC
NLC
1.3xlO-6
NLC
NLC
2.5xlO"6
NLC
NLC
5xlO'6
Loading^
(Ib/ton)
(0.0016)
(0.0036)
(0.010)
(0.012)
(0.006)
(0.006)
(0.0004)
(4x10^)
(2xlO"4)
(0.00361
(4xlO'5)
(2.6xlO"6)
(llxlQ-5)
(0.0002)
(2.6xlO"7)
(2.6xlQ-6)
(5xlO~6)
(IxlO'5)
Source: RAPP data.
NLC = no loadings calculable.
77
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TABLE 22. CHARACTER OF WASTE WATER
FROM NONCONTACT COOLING
(PLANT R, PIPE 010)
Volume: 643,000 I/day (170,000 gal/day)
Operations: Noncontact cooling water, cooling tower blowdown
(hot side)
Production: 149.7 kkg/day (165 tons/day)
Constituent
Alkalinity
BOD, 5 -day
COD
Solids
Diss. Solids
Susp. Solids
Total Vol. Solids
Nitrate (as N)
Kjeldahl Nitrogen
Ammonia (as N)
Phosphorus (as P)
Sulfate (as S)
Sulfide (as S)
Chloride
Fluoride
Aluminum
Antimony
Arsenic
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Mercury
Nickel
Potassium
Silver
Sodium
Tin
Titanium
Oil and Grease
Surfactants
PH
Temp (Win),C(F)
Temp (Sum).C(F)
Intake,
mg/1
15
0
19
90
58
14
44
1.75
1.54
0.05
0.02
0.6
0.1
14
1.16
0.020
0
0
7.5
0.010
0
0
0.400
0
5
0.050
0
0
0.35
0
25
0
0
4.1
0.6
6.85
14(58)
16(60)
Discharge,
mg/1
18
1.0
26
116
82
26
68
1.0
2.38
0.02
0.08
1.2
0.1
21
1.2
0.020
0
0
7.5
0.015
0
0.225
0.350
0.425
5
0.025
0.0005
0
0.35
0.005
25
0
0.010
3.9
0.62
6.85
29(84)
30(86)
Net Concv
mg/1
3
1
7
26
24
12
24
-0.75
0.84
-0.03
0.06
0.6
0
7
0.04
0
0
0
0
0.005
0
0.225
-0.050
0.425
0
-0.025
0.0005
0
0
0.005
0
0
0.010
-0.2
0.02
Net Loading
kg/kkg
0.013
0.004
0.030
0.117
0.104
0.052
0.104
NLC
0.0036
NLC
2.6xlO'4
0.0026
NLC
0.030
1.7xlO'4
NLC
NLC
NLC
NLC
2xlO"5
NLC
9.7xlO'4
NLC
0.0018
NLC
NLC
2.1xlO"6
NLC
NLC
2xlO'5
NLC
NLC
4.3xlO"5
NLC
8.6x10-5
(Ib/day)
(0.026)
(0.008)
(0.060)
(0.234)
(0.208)
(0.104)
(0.208)
(0.0072)
(5.2xlO~4)
(0.0052)
(0.060)
(3.4xlO~4)
(4xlO'5)
(1.9xlO~3)
(0.0037)
(4.2xlO'6)
(4xlO-5)
(8.6xlO-5)
(1.7xlO"4)
Source: RAPP data.
NLC = no loadings calculable.
78
-------
TABIE 23. CHARACTER OB kASTE WATER FRCM PLAI.T RUNOFF, PLANT y,
Discharge to River
Volume: unknown (a,b) (i/2 inches of rain)
Product: 9.7 kkg/day (1007 ton/day)
Intake
Cone.
Constituent tng/1
Alkalinity
COD
Solids
Diss. Solids
Susp. Solids
Phosphorus
Cyanide
Ant imony
Arsenic
Boron
Cadmium
Copper
Iron
Lead
Manganese
Mercury
Nickel
Zinc
Oil and Grease
Discharge
Cone. Loadingi
mg/1 kg/kkg
54
--
414
302
112
0.50
0.07
0.1
< 0.02
0,2
< 0.05
3
10
1
0.6
< 0.001
< 0.1
006
--
PH 7.7
(a) Water runoff flow unknown,,
(b) NLC = no loadings calculable because flow is unknown.
79
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SECTION VI
SELECTION OF POLLUTANT PARAMETERS
Introduction
The wastewater constituents which have been determined to be
present in the process wastewaters of the segment of the
secondary copper industry which discharges to POTW and which
are present in some process waste water streams in
sufficient quantities to warrant control and treatment are
copper, cadmium, and oil and grease.
This section provides the rationale for the selection, as
well as the rejection, of pollutant characteristics for this
subcategory.
Rationale for Selection of
Pollutant Parameters
The control and treatment technologies discussed in Section
VII describe the current practices by the industry which are
used to treat and control the selected pollutants. From
these discussions, it was concluded that the discharge of
metals can be controlled by pH adjustment (if necessary) and
suspended solids removal.
Setting effluent limitations on the prescribed metals, which
are the principal pollutant metals in the process waters
from secondary copper smelters discharging to POTW will in
turn limit the other trace metals found in these waste
waters. Such metals may include lead, zinc, aluminum,
magnesium, antimony, chromium, cobalt, iron, manganese,
nickel, silver, and tin.
There is an optimum pH for precipitation of each metal,
which results in its greatest reduction by solids removal
(settling or filtration). Although pH is not specifically
identified as a parameter to be controlled, the limits
prescribed for metals will require a pH adjustment to within
a range which is a compromise between the maximum removal of
copper and zinc, as hydroxides, and that suited for maximum
removal of cadmium, lead, antimony, tin, and other metals
associated with the raw scrap metal source. Coprecipitation
of these metal hydroxides with copper and zinc hydroxide
(and also aluminum, iron, and magnesium hydroxide, if they
are present in the waste water) at a pH at which optimum
81
-------
coprecipitation occurs is used in good water treatment
practice. Therefore, an appropriate pH adjustment followed
by solids removal will reduce all the metals to technically
practicable levels.
Cadmium
Cadmium is a relatively rare element that is seldom found in
sufficient quantities in a pure state to warrant mining or
extraction from the earth's surface. It is found in trace
amounts of about 1 ppm throughout the earth's crust.
Cadmium is, however, a valuable by-product of zinc
production.
Cadmium is used primarily as a metal plating material and
can be found as an impurity in the secondary refining of
zinc, lead, and copper. Cadmium is also used in the
manufacture of primary cells of batteries and as a neutron
adsorber in nuclear reactors. Other uses of cadmium are in
the production of pigments, phosphors, semi-conductors,
electrical contactors, and special purpose low temperature
alloys.
Cadmium is an extremely dangerous cumulative toxicant,
causing insidious progressive chronic poisoning in mammals,
fish, and probably other animals because the metal is not
excreted. Cadmium could form organic compounds which might
lead to mutagenic or teratogenic effects. Cadmium is known
to have marked acute and chronic effects on aquatic
organisms also.
Toxic effects of cadmium on man have been reported from
throughout the world. Cadmium is normally ingested by
humans through food and water and also by breathing air
contaminated by cadmium. Cadmium in drinking water suppli?s
is extremely hazardous to humans, and conventional
treatment, as practiced in the United States, does not
remove it. Cadmium is cumulative in the liver, kidney,
pancreas, and thyroid of humans and other animals. A severe
bone and kidney syndrome in Japan (Itai-Itai, or literally,
Ouch-Ouch disease) has been associated with the ingestion of
as little as 600 ug/day of cadmium. The allowable cadmium
concentration in drinking water is set as low as 0.01 mg/1
in the U. S. and as high as 0.10 mg/1 in Russia.
Cadmium acts synergistically with other metals. Copper and
zinc substantially increase its toxicity. Cadmium is
concentrated by marine organisms, particularly molluscs,
which accumulate cadmium in calcareous tissues and in the
viscera. Cadmium has been found in fish muscle in
82
-------
concentrations up to 1000 times the ambient concentration of
the metal, up to 3000 times in marine plants, and up to
29,600 times the ambient concentration in certain marine
animals. The eggs and larvae of fish are apparently more
sensitive than adult fish to poisoning by cadmium, and
crustaceans appear to be more sensitive than fish eggs and
larvae.
Cadmium, as well as most metals, is generally not
susceptible to treatment by biological treatment processes
at POTW. Significant quantities of the input metal may pass
through the treatment plant, while the remainder is removed
through the settling of the hydroxide of the metal and by
adsorption onto sludge particles. This settled and adsorbed
cadmium will tend to concentrate in the sludge, thus
restricting further reuse and disposal of the sludge. in
addition, cadmium can interfere with the operation of POTW
using biological processes by reducing overall removal
efficiencies, largely as a result of the toxicity of the
metal to biological organisms.
When the sludge from the POTW is disposed of on land, the
cadmium contained therein is absorbed readily by plants and
tends to concentrate in the plant tops. Rice and soybeans
both take up and concentrate cadmium found in the soil. In
Japan, a limit of 1 mg/1 was established as the maximum
allowable concentration of cadmium in unpolished rice.
While cadmium in the soil causes iron deficiencies in
plants, if the zinc to cadmium ratio is greater than 200,
plants will not be able to accumulate a hazardous
concentration of cadmium, since the two metals compete at
the site of uptake and the plants will be poisoned by zinc
before accumulating dangerous levels of cadmium.
Copper
Copper is an elemental metal that is sometimes found free in
nature and is found in many minerals such as cuprite,
malachite, azurite, chalcopyrite, and bornite. Copper is
obtained from these ores by smelting, leaching, and
electrolysis. Significant industrial uses are in the
plating, electrical, plumbing, and heating equipment
industries. Copper is also commonly used with other
minerals as an insecticide and fungicide.
Traces of copper are found in all forms of plant and animal
life, and it is an essential trace element for nutrition.
Copper is not considered to be a cumulative systemic poison
for humans as it is readily excreted by the body, but it can
cause symptoms of gastroenteritis, with nausea and
83
-------
intestinal irritations, at relatively low dosages. The
limiting factor in domestic water supplies is taste.
Threshold concentrations for taste have been generally
reported in, the range of 1.0 - 2.0 mg/1 of copper while
concentrations of 5 to 7.5 mg/1 have made water completely
undrinkable. It has been recommended that the copper in
public water supply sources not exceed 1 mg/1.
Copper salts cause undesirable color reactions in the food
industry and cause pitting when deposited on some other
metals such as aluminum and galvanized steel. The textile
industry is affected when copper salts are present in water
used for processing of fabrics. Irrigation waters con-
taining more than minute quantities of copper can be
detrimental to certain crops. The toxicity of copper to
aquatic organisms varies significantly, not only with the
species, but also with the physical and chemical
characteristics of the water, including temperature,
hardness, turbidity, and carbon dioxide content. In hard
water, the toxicity of copper salts may be reduced by the
precipitation of copper carbonate or other insoluble
compounds. The sulfates of copper and zinc, and of copper
and cadmium are synergistic in their toxic effect on fish.
Copper concentrations less than 1 mg/1 have been reported to
be toxic, particularly in soft water, to many kinds of fish,
crustaceans, mollusks, insects, phytoplankton and
zooplankton. Concentrations of copper, for example, are
detrimental to some oysters above 0.1 mg/1. Oysters,
cultured in sea water containing 0.13-0.5 mg/1 of copper,
deposited the metal in their bodies and became unfit as a
food substance.
The toxic effects of copper are compounded when certain
other metals are present. Copper and zinc have been
reported to be five times as toxic when combined than would
be expected considering the toxicity of each metal
separately. Increased toxicological effects of a similar
magnitude have been noted between copper and cadmium, and
other synergistic toxic effects of copper have been observed
when mercury or phosphates are present.
Copper, as well as most metals, is generally not susceptible
to treatment by biological treatment processes at POTW.
Research has shown that up to half of the input, metal will
pass through the treatment plant, with about 30 to 50
percent of the copper which passes through the plant
appearing in the soluble state. Digestion has been impaired
by copper continuously fed at 10 mg/1, and slug doses of
copper at 50 mg/1 for four hours in an unacclimated system
84
-------
have resulted in greatly decreased efficiencies of treatment
plants for up to 100 hours.
The copper that is removed from the influent stream by the
POTW is adsorbed on the sludge, or it appears in the sludge
as the hydroxide of the metal. Experimental data shows that
when dried sludge is spread over tillable land, the copper
tends to remain in place down to the depth of tillage,
except for that copper that is taken up by plants grown in
the soil. Copper tends to concentrate in the roots of
plants, and has shown little tendency to migrate to other
parts of the plant. In most cases, the concentration of
copper in plants will kill the plant before it has reached a
high enough concentration to evidence harm in animals that
may eat the plants, although it is reported that copper
concentrated in plants has resulted in fatalities among
sheep.
Oil and Grease
Because of widespread use, oil and grease occur often in
waste water streams. These oily wastes may be classified as
follows:
1. Light Hydrocarbons - These include light fuels such
as gasoline, kerosene, and jet fuel, and
miscellaneous solvents used for industrial
processing, degreasing, or cleaning purposes. The
presence of these light hydrocarbons may make the
removal of other heavier oily wastes more
difficult.
2. Heavy Hydrocarbons, Fuels, and Tars - These include
the crude oils, diesel oils, #6 fuel oil, residual
oils, slop oils, and in some cases, asphalt and
road tar.
3. Lubricants and Cutting Fluids - These generally
fall into two classes: non-emulsifiable oils such
as lubricating oils and greases and emulsifiable
oils such as water soluble oils, rolling oils,
cutting oils, and drawing compounds. Emulsifiable
oils may contain fat soap or various other
additives.
4. Vegetable and animal fats and oils - These
originate primarily from processing of foods and
natural products.
85
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These compounds can settle or float and may exist as
solids or liquids depending upon factors such as method
of use, production process, and temperature of waste
water.
Oils and grease even in small quantities cause troublesome
taste and odor problems. Scum lines from these agents are
produced on water treatment basin walls and other
containers. Fish and water fowl are adversely affected by
oils in their habitat. Oil emulsions may adhere to the
gills of fish causing suffocation, and the flesh of fish is
tainted when microorganisms that were exposed to waste oil
are eaten. Deposition of oil in the bottom sediments of
water can serve to inhibit normal benthic growth. Oil and
grease exhibit an oxygen demand.
Levels of oil and grease which are toxic to aquatic
organisms vary greatly, depending on the type and the
species susceptibility. However, it has been reported that
crude oil in concentrations as low as 0.3 mg/1 is extremely
toxic to fresh-water fish. It has been recommended that
public water supply sources be essentially free from oil and
grease.
Oil and grease in quantities of 100 1/sq km (10 gallons/sq
mile) show up as a sheen on the surface of a body of water.
The presence of oil slicks prevent the full aesthetic
enjoyment of water. The presence of oil in water can also
increase the toxicity of other substances being discharged
into the receiving bodies of water.
Rationale for Rejection of Other Waste Water
Constituents as Pollutant Parameters
The following pollutants were determined not to warrant
inclusion as parameters for pretreatment standards:
Acidity and Alkalinity - pH
Antimony
Boron
Lead
Oxygen Demand (BOD and CCD)
Total Suspended Solids
Zinc
Acidity and Alkalinity - pH
Although not a specific pollutant, pH is related to the
acidity or alkalinity of a waste water stream. It is not a
linear or direct measure of either, however, it may properly
86
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be used as a surrogate to control both excess acidity and
excess alkalinity in water. The term pH is used to describe
the hydrogen ion - hydroxyl ion balance in water.
Technically, pH is the hydrogen ion concentration or
activity present in a given solution. pH numbers are the
negative logarithm of the hydrogen ion concentration. A pH
of 7 generally indicates neutrality or a balance between
free hydrogen and free hydroxyl ions. Solutions with a pH
above 7 indicate that the solution is alkaline, while a pH
below 7 indicates that the solution is acid.
Knowledge of the pH of water or waste water is useful in
determining necessary measures for corrosion control,
pollution control, and disinfection. Waters with a pH below
6.0 are corrosive to water works structures, distribution
lines, and household plumbing fixtures and such corrosion
can add constituents to drinking water such as iron,
copper, zinc, cadmium, and lead. Low pH waters not only
tend to dissolve metals from structures and fixtures but
also tend to redissolve or leach metals from sludges and
bottom sediments. The hydrogen ion concentration can affect
the "taste" of the water and at a low pH, water tastes
"sour".
Extremes of pH or rapid pH changes can exert stress
conditions or kill aquatic life outright. 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. For example, metalocyanide complexes can
increase a thousand-fold in toxicity with a drop of 1.5 pH
units. Similarly, the toxicity of ammonia is a function of
pH. The bactericidal effect of chlorine in most cases is
less as the pH increases, and it is economically
advantageous to keep the pH close to 7.
Acidity is defined as the quantitative ability of a water to
neutralize hydroxyl ions. It is usually expressed as the
calcium carbonate equivalent of the hydroxyl ions
neutralized. Acidity should not te confused with pH value.
Acidity is the quantity of hydrogen ions which may be
released to react with or neutralize hydroxyl ions while pH
is a measure of the free hydrogen ions in a solution at the
instant the pH measurement is made. A property of many
*The term toxic or toxicity is used herein in the normal
scientific sense of the word and not as a specialized
term referring to section 307(a) of the Act.
87
-------
chemicals, called buffering, may hold hydrogen ions in a
solution from being in the free state and being measured as
pH. The bond of most buffers is rather weak and hydrogen
ions tend to be released from the buffer as needed to
maintain a fixed pH value.
Highly acid waters are corrosive to metals, concrete and
living organisms, exhibiting the pollutional characteristics
outlined above for low pH waters. Depending on buffering
capacity, water may have a higher total acidity at pE values
of 6.0 than other waters with a pH value of 4.0.
Alkalinity: Alkalinity is defined as the ability of a water
to neutralize hydrogen ions. It is usually expressed as the
calcium carbonate equivalent of the hydrogen ions
neutralized.
Alkalinity is commonly caused by the presence of carbonates,
bicarbonates, hydroxides and to a lesser extent by borates,
silicates, phophates and organic substances. Because of the
nature of the chemicals causing alkalinity, and the
buffering capacity of carbon dioxide in water, very high pH
values are seldom found in natural waters.
Excess alkalinity as exhibited in a high pH value may make
water corrosive to certain metals, detrimental to most
natural organic materials and toxic to living organisms.
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.
Acidity and Alkalinity pH are not established as
parameters since 40 CFR 128.131 generally establishes a
minimum pH level of 5 for the introduction of wastes to
POTW. This limit is specifically restated for the secondary
copper industry in 40 CFR 121.64 to avoid confusion. In
addition, pH is effectively limited by establishing
standards for copper and cadmium since the pH of the
wastewater must be carefully controlled to between 8 and 10
to meet these standards.
Antimony (Sb)
Antimony is an elemental metal that is not abundant in
nature in a pure state but is found in over 100 mineral
species. Antimony forms salts with +3 and +5 valences. The
trichloride, sulfate, potassium tartrate, and peritachloride
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salts are soluble in water. Antimony tends to be
precipitated as Sb203. or Sb2O5. The sulfides are insoluble
in water. Consequently, any dissolved antimony that might
be discharged to natural waters soon precipitates and is
removed by sedimentation or adsorption.
Antimony is found as an alloy in lead, zinc, and copper and,
thus, machined and processed as an alloy. It is also found
in paints and in the manufacture of batteries, type metals,
and cable sheathing.
There is no evidence that antimony is an essential element
in human nutrition, but it has been found to be toxic.
Compounds of antimony are poisonous and classed as acutely
moderate or chronically severe. The toxic effects of
antimony are reported to be similar in character to the
toxic effects of arsenic. Moderate toxicity includes injury
to internal organs and severe toxicity means debilitating
effects or death. A dose of 97.2 mg of antimony has
reportedly been lethal to an adult. Antimony has been used
for treatment of certain tropical parasitic diseases but is
no longer recommended because of the frequency and severity
of toxic reactions.
Antimony can be concentrated by certain forms of aquatic
life to over 300 times its concentration in the surrounding
waters. The salts of antimony in tests on various fish and
aquatic life gave mixed toxicity results depending on the
salt, temperature, hardness of the water, and dissolved
oxygen present.
The inhibitory effects of antimony upon sewage treatment
systems and upon subsequent use of sewage sludges are not
well documented in the literature. Available evidence
indicates that this pollutant is partially removed when pH
adjustment and settling is employed for removal of metals,
with the lower solubility limit occurring in weakly alkaline
pH ranges.
Boron (B)
Never found in nature in its elemental form, boron occurs as
sodium borate (borax) or as calcium borate (colemanite) in
mineral deposits and natural waters of Southern California
and Italy. Elemental boron is used in nuclear installations
as a shielding material (neutron absorber) . It is also used
in metallurgy to harden other metals.
Boric acid and boron salts are used extensively in industry
for such purposes as weatherproofing wood, fireproofing
39
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fabrics, manufacturing glass and porcelain and producing
leather, carpets, cosmetics and artificial gems. Boric acid
is used as a bactericide and fungicide and boron, in the
form of boron hydrides or borates, is used in high energy
fuels. y*
Boron is present in the ordinary human diet at about 10 to
20 mg/day, with fruits and vegetables being the largest
contributors. In food or in water, it is rapidly and
completely absorbed by the human system, but it is also
promptly excreted in urine. Boron in drinking water is not
generally regarded as a hazard to humans. It has been
reported that boron concentrations up to 30 mg/1 are not
harmful.
Boron is not regulated since it appears in waste streams in
concentrations which are well below the limits attainable by
current treatment technology where pH adjustment and
subsequent settling are employed. It should be noted,
however, that some absorption of the element may occur where
charcoal cover residues are present in the waste stream.
Lead
Lead is a toxic material that is foreign to humans and
animals. The most common form of lead poisoning is called
plumbism. Lead can be introduced into the body from the
atmosphere containing lead or from food and water. Lead
cannot be easily excreted and is cumulative in the body over
long periods of time, eventually causing lead poisoning with
the ingestion of an excess of 0.6 mg per day over a period
of years. It has been recommended that 0.05 mg/1 lead not
be exceeded in public water supply sources.
Chronic lead poisoning has occurred among animals at levels
of 0.18 mg/1 of lead in soft water and by concentrations
under 2.4 mg/1 in hard water. Farm animals are poisoned by
lead more frequently than any other poison. Sources of this
occurrence include paint and water with the lead in solution
as well as in suspension. Each year thousands of wild water
fowl are poisoned from lead shot that is discharged over
feeding areas and ingested by the water fowl. The bacterial
decomposition of organic matter is inhibited by lead at
levels of 0.1 to 0.5 mg/1.
Fish and other marine life have had adverse effects from
lead and salts in their environment. Experiments have shown
that small concentrations of metals, especially of lead,
have caused a film of coagulated mucus to form first over
the gills and then over the entire body probably causing
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suffocation of the fish due to this obstructive layer.
Toxicity of lead is increased with a reduction of dissolved
oxygen concentration in the water.
Lead, as well as most metals, is generally not susceptible
to treatment by biological treatment processes at POTW.
Significant quantities of the input metal will pass through
the treatment plant, while the remainder is removed through
the settling of the hydroxide of the metal and by adsorption
onto sludge particles. This settled and adsorbed lead will
tend to concentrate in the sludge, which may restrict
further reuse and disposal of the sludge. Available
evidence, however, indicates that plants are susceptible to
injury from soil-borne lead only in low-phosphate acid
soils. The presence of phosphate apparently immobilizes
lead in soil, and when phosphate is present, lead is not
translocated to plants in significant quantities,
particularly when the soil is not acidic.
Lead is not regulated since it is effectively removed with
copper in a pH adjustment and settle treatment system. The
optimum pH for precipitation of lead is nearly identical to
the optimum pH for the removal of copper.
Oxygen Demand (BOD and COD)
Organic and some inorganic compounds can cause an oxygen
demand to be exerted in a receiving body of water.
Indigenous microorganisms utilize the organic wastes as an
energy source and oxidize the organic matter. In doing so
their natural respiratory activity will utilize the
dissolved oxygen.
Biochemical oxygen demand (BOD) is the quantity of oxygen
required for the biological and chemical oxidation of
waterborn substances under ambient or test conditions.
Materials which may contribute to the BOD include:
carbonaceous organic materials usable as a food source by
aerobic organisms; oxidizable nitrogen derived from
nitrites, ammonia and organic nitrogen compounds which serve
as food for specific bacteria; and certain chemically
oxidizable materials such as ferrous iron, sulfides,
sulfite, etc. which will react with dissolved oxygen or are
metabolized by bacteria. In most industrial and municipal
waste waters, the BOD derives principally from organic
materials and from ammonia (which is itself derived from
animal or vegetable matter).
The BOD of a waste exerts an adverse effect upon the
dissolved oxygen resources of a body of water by reducing
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the oxygen available to fish, plant life, and other aquatic
species. Conditions can be reached where all of the
dissolved oxygen in the water is utilized resulting in
anaerobic conditions and the production of undesirable gases
such as hydrogen sulfide and methane. The reduction of
dissolved oxygen can be detrimental to fish populations,
fish growth rate, and organisms used as fish food. A total
lack of oxygen due to the exertion of an excessive BOD can
result in the death of all aerobic aquatic inhabitants in
the affected area.
Water with a high BOD indicates the presence of decomposing
organic matter and associated increased bacterial
concentrations that degrade its quality and potential uses.
A by-product of high BOD concentrations can be increased
algal concentrations and blooms which result from
decomposition of the organic matter and which form the basis
of algal populations.
The BOD5 (5-day BOD) test is used widely to estimate the
pollutional strength of domestic and industrial wastes in
terms of the oxygen that they will require if discharged
into receiving streams. The test is an important one in
water pollution control activities. It is used for
pollution control regulatory activities, to evaluate the
design and efficiencies of waste water treatment works, and
to indicate the state of purification or pollution of
receiving bodies of water.
Complete biochemical oxidation of a given waste may require
a period of incubation too long for practical analytical
test purposes. For this reason, the 5-day period has been
accepted as standard, and the test results have been
designated as BODjj. Specific chemical test methods are not
readily available for measuring the quantity of many
degradable substances and their reaction products. Reliance
in such cases is placed on the collective parameter, BOD5_,
which measures the weight of dissolved oxygen utilized by
microorganisms as they oxidize or transform the gross
mixture of chemical compounds in the waste water. The
biochemical reactions involved in the oxidation of carbon
compounds are related to the period of incubation. The
five-day BOD normally measures only 60 to 80% of the
carbonaceous biochemical oxygen demand of the sample, and
for many purposes this is a reasonable parameter.
Additionally, it can be used to estimate the gross quantity
of oxidizable organic matter.
The BOD_5 test is essentially a bioassay procedure which
provides an estimate of the oxygen consumed by
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microorganisms utilizing the degradable matter present in a
waste under conditions that are representative of those that
are likely to occur in nature. Standard conditions of time,
temperature, suggested microbial seed, and dilution water
for the wastes have been defined and are incorporated in the
standard analytical procedure. Through the use of this
procedure, the oxygen demand of diverse wastes can be
compared and evaluated for pollution potential and to some
extent for treatability by biological treatment processes.
Because the BOD test is a bioassay procedure, it is
important that the environmental conditions of the test be
suitable for the microorganisms to function in an
uninhibited manner at all times. This means that toxic
substances must be absent and that the necessary nutrients,
such as nitrogen, phosphorous, and trace elements, must be
present.
Chemical oxygen demand (COD) is a purely chemical oxidation
test devised as an alternate method of estimating the total
oxygen demand of a waste water. Since the method relies on
the oxidation-reduction system of chemical analyses rather
than on biological factors, it is more precise, accurate,
and rapid than the BOD test. The COD test is widely used to
estimate the total oxygen demand (ultimate rather than 5-day
BOD) to oxidize the compounds in a waste water. It is based
on the fact that organic compounds, with a few exceptions,
can be oxidized by strong chemical oxidizing agents under
acid conditions with the assistance of certain inorganic
catalysts.
The COD test measures the oxygen demand of compounds that
are biologically degradable and of many that are not.
Pollutants which are measured by the BOD_5 test will be
meausred by the COD test. In addition, pollutants which are
more resistant to biological oxidation will also be measured
as COD. COD is a more inclusive measure of oxygen demand
than is BOD5_ and will result in higher oxygen demand values
than will the BODJ5 test.
The compounds which are more resistant to biological
oxidation are becoming of greater and greater concern not
only because of their slow but continuing oxygen demand on
the resources of the receiving water, but also because of
their potential health effects on aquatic life and humans.
Many of these compounds result from industrial discharges
and some have been found to have carcinogenic, mutagenie and
similar adverse effects, either singly or in combination.
Concern about these compounds has increased as a result of
demonstrations that their long life in receiving waters -
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the result of a slow biochemical oxidation rate - allows
them to contaminate downstream water intakes. The commonly
used systems of water purification are not effective in
removing these types of materials and disinfection such as
chlorination may convert them into even more hazardous
materials.
Thus the COD test measures organic matter which exerts an
oxygen demand and which may affect the health of the people.
It is a useful anlytical tool for pollution control
activities. It provides a more rapid measurement of the
oxygen demand and an estimate of organic compounds which are
not measured in the BODj> test.
Oxygen demand (BOD and COD) was not selected as a pollutant
parameter because this characteristic is compatible with the
operation of POTW.
Total Suspended Solids (TSS)
Suspended solids include both organic and inorganic
materials. The inorganic compounds include sand, silt, and
clay. The organic fraction includes such materials as
grease, oil, tar, and animal and vegetable waste products.
These solids may settle out rapidly and bottom deposits are
often a mixture of both organic and inorganic solids.
Solids may be suspended in water for a time, and then settle
to the bed of the stream or lake. These 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.
Suspended solids (TSS), including both organic and inorganic
materials, do not normally pass through or interfere with
the operation of publicly owned treatment works (POTW).
Levels of suspended solids high enough to plug pipes or to
interfere with the operation of pumps at POTW were not found
in raw waste streams from secondary copper smelters.
Moreover, suspended solids loadings are indirectly
controlled by the limits set on metals, since these limits
will require settling of the hydroxides of the metals
(following pH adjustment as necessary).
Zinc
Occurring abundantly in rocks and ores, zinc is readily
refined into a stable pure metal and is used extensively for
galvanizing, in alloys, for electrical purposes, in printing
94
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plates, for dye manufacture and for dyeing processes, and
for many other industrial purposes. Zinc salts are used in
paint pigments, cosmetics, Pharmaceuticals, dyes,
insecticides, and other products too numerous to list
herein. Many of these salts (e.g., zinc chloride and zinc
sulfate) are highly soluble in water; hence it is to be
expected that zinc might occur in many industrial wastes.
On the other hand, some zinc salts (zinc carbonate, zinc
oxide, zinc sulfide) are insoluble in water and consequently
it is to be expected that some zinc will precipitate and be
removed readily in most natural waters.
In zinc mining areas, zinc has teen found in waters in
concentrations as high as 50 mg/1 and, in effluents from
metal-plating works and small-arms ammunition plants, it may
occur in significant concentrations. In most surface and
ground waters, it is present only in trace amounts. There
is some evidence that zinc ions are adsorbed strongly and
permanently on silt, resulting in inactivation of the zinc.
Concentrations of zinc in excess of 5 mg/1 in raw water used
for drinking water supplies cause an undesirable taste which
persists through conventional treatment. Zinc can have an
adverse effect on man and animals at high concentrations.
In soft water, concentrations of zinc ranging from 0.1 to
1.0 mg/1 have been reported to te lethal to fish. Zinc is
thought to exert its toxic action by forming insoluble
compounds with the mucous that covers the gills, by damage
to the gill epithelium, or possibly by acting as an internal
poison. The sensitivity of fish to zinc varies with
species, age and condition, as well as with the physical and
chemical characteristics of the water. Some acclimatization
to the presence of zinc is possible. It has also been
observed that the effects of zinc poisoning may not become
apparent immediately, so that fish removed from zinc-
contaminated to zinc-free water (after U-6 hours of exposure
to zinc) may die 48 hours later. The presence of copper in
water may increase the toxicity of zinc to aquatic
organisms, but the presence of calcium or hardness may
decrease the relative toxicity.
Observed values for the distribution of zinc in ocean waters
vary widely. The major concern with zinc compounds in
marine waters is not one of acute toxicity, but rather of
the long-term sub-lethal effects of the metallic compounds
and complexes. From an acute toxicity point of view,
invertebrate marine animals seem to be the most sensitive
organisms tested. The growth of the sea urchin, for
example, has been retarded by as little as 30 ug/1 of zinc.
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Zinc is readily taken up and translocated within plants.
The activity of zinc is most profound in acid soils and
decreases in the presence of large amounts of phosphate, as
would be found in sludges from POTW. For each unit increase
in the pH, there is a hundredfold decrease in the toxicity
of zinc. In plants the poisoning mechanism is iron
deficiency, and to avoid this, lime must be added to the
soil to maintain soil pH above 6.0. Generally, zinc will
kill the plants before reaching concentrations harmful to
animals in the plants.
Dissolved zinc is generally not susceptible to treatment by
biological treatment processes at POTW. In slug doses, and
particularly in the presence of copper, dissolved zinc can
interfere with or seriously disrupt the operation of POTW
using biological processes by reducing overall removal
efficiencies, largely as a result of the toxicity of the
metal to biological organisms. However, zinc solids (in the
form of hydroxides or sulfides do not appear to interfere
with biological treatment processes on the basis of
available data. Such solids accumulate in the sludge, where
subsequent effects depend on the sludge disposal method.
Zinc is not regulated since it is effectively removed with
copper in a pH adjustment and settle treatment system. The
optimum pH for precipitation of lead is nearly identical to
the optimum pH for the removal of copper.
Chromium^ Mercury, and Nickel
Each of these pollutants can pose a threat to the operation
of a POTW when present in significant amounts. Available
evidence, however, indicates that these pollutants are
either not found in process waste water streams from
secondary copper smelters or are present in concentrations
which are well below the limits attainable by current
treatment technology. Their inclusion as pollutant
parameters is therefore not warranted.
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SECTION VII
CONTROL AND TREATMENT TECHNOLOGY
Introduction
The control and treatment technologies available to that
segment of the secondary copper industry discharging to POTW
are the same as those available to that segment of the
industry which discharges directly to surface waters or
which completely recycles and reuses all process waste
waters with no resultant discharge. The most significant
difference is that POTW dischargers avail themselves of
public facilities for treatment of process wastewaters, so
that process water discharges from POTW users generally
receive less treatment than may te found at other plants in
the industry. In most cases the process waste water
discharges from indirect dischargers is not treated at all
prior to discharge to a POTW.
The control and treatment technologies that are currently
being used for reducing discharge of pollutants in waste
water from contact cooling of molten metal, from slag
granulation, from furnace exhaust scrubbing, and from
electrolytic cell operation are discussed in this section.
The discussion includes a range of treatment alternatives
for each type of waste water stream. Alternative control
technologies that could limit or eliminate the effluent
originating from the processes are identified. Control and
treatment technologies for waste water from slag milling and
classification operations are not discussed since no plants
discharging to POTW perform this operation.
In this context the term "control technology" refers to any
practice applied in order to reduce the volume of waste
water discharged. "Treatment technology" refers to any
practice applied to a waste water stream to reduce the
concentration of pollutants in the stream before discharge.
As set forth in Section VI, the constituents of waste water
from the secondary copper industry that are to be considered
as pollutants of significance are ccpper, cadmium and oil
and grease. These pollutants in the discharge water
originate from the operations of wet scrubbing of melting
and refining furnace exhausts, slag quenching and
granulation, contact cooling of molten metal, and
electrolytic refining cell operations.
97
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A diagram illustrating those operations in which water is
used in the production of refined copper and copper alloy
ingots is presented in Figure 3. In addition to the
operations already cited, water is used for equipment and
other non-contact cooling operations and for sanitation.
Runoff water at some plants may also be collected and mixed
with process water.
In general, coarse solids settling is the only pre treatment
technique employed prior to discharge to POTW. Water
recycle is widely employed by POTW dischargers and may be a
result of minimizing, or in many cases completely avoiding,
sewer district user fees which are based in part on volumes
discharged to the POTW.
Water from Contact Cooling of Molten Metal
All of the seventeen plants which discharge process water to
POTW use water for quenching and cooling of molten metal
ingots, anodes, billets, and shot. Recycle and reuse of
this contact cooling water with minor bleeds or overflows to
POTW is the dominant practice in this segment of the
industry. Most plants recycle and reuse most cooling water
and discharge volumes ranging from a few hundred gallons a
day to a few thousand gallons a day. Cooling water is often
discharged only once a week or once a month to allow
cleaning of quench pits. One indirect discharger completely
recycles process water at this operation. By contrast,
another discharges cooling water used only once, discharging
up to 760,000 gallons per day from a shot quenching
operation. Several large plants exhibited discharge rates
of one to three hundred thousand gallons per day, ev~n
though partial recycle of contact metal cooling water is
practiced.
Anodes, billets and rough brass or bronze ingots are
generally water spray-cooled to rapidly solidify the
casting, and the casting is then quenched in a tank of
water. Smooth brass or bronze ingots must be slowly cooled
in the mold under a layer of charcoal to produce the smooth
surface requested by certain customers. Ingot mold lines
are quite long for the production of smooth ingots. The
ingots are permitted to air cool in the mold during the
first portion of the conveyer travel, the bottom of the
ingot mold is submerged in a tank of water during the second
portion of the conveyer travel, and finally the solidified
ingot is discharged into a quenching tank of water. Part of
the charcoal burns during the ingots' travel period on the
conveyer. The unburned charcoal and charcoal ash all go
into the ingot cooling water. These residues settle as a
98
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sludge and are periodically cleaned out of the quenching
tanks and subsequent settling tanks cr ponds. The water may
or may not be recycled. In addition to the charcoal and
charcoal ash, the water contains a small amount of metal
oxide from the ingot surface, refractory mold wash,
lubricants, and dust from the smelter floor. These
contaminants are observed as loadings cf suspended solids,
metals, and oil and grease.
Shot is produced by quenching mclten copper in water,
usually after a stream of the molten material has been
broken up into droplets with high pressure air and water or
by flat vessels with appropriately spaced holes. Waste
water is generated when quench pits are discharged for
cleaning.
Current treatment and control alternatives employed by the
industry for the reduction of water use and the removal of
pollutants are diagrammed in Figure 4. Various levels of
technology are indicated, ranging from no treatment before
discharge to various types of solids removal that enable
total reuse of water either for molten metal cooling or in
other process streams. In the diagram, the complexity of
the water treatment alternatives increases from 1, which is
no treatment, to 6, which can be operated with no discharge
of waste water.
Identification of Control Alternatives
The amount of waste water generated in molten metal cooling
can be reduced by recirculation and cooling. If for no
other reason than economy, this is the practice used by the
industry, particularly among the twenty-nine direct
dischargers. The amounts of pollutants added to the stream
could be reduced significantly if non-contact cooling were
used instead of contact cooling. The use of water could be
eliminated if air cooling of the molten metal were employed.
However, such a method would be suited for only low tonnage
producers.
Air Cooling of Molten Metal. Air cooling of molten metal is
employed only by small tonnage specialty alloy producers.
It is also used for the casting of blister copper in
graphite molds when such material is to be shipped or when
production of refined copper is cut of phase with blast
furnace and converter operation.
Air cooling is not employed in the production of large
tonnage metal for several reasons. The casting line would
be inordinately long (or large), requiring a large number of
99
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Water Source
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O
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Figure 4. Current treatment and control technology alternatives for
waste water from contact cooling of no!ten metal.
-------
molds to allow the metal to cool enough to be handled.
Maintenance would be higher because of the longer conveyer,
the added heat load on equipment and lubricants, and the
need for added blower motors. Air cooling would greatly
reduce the rate of finished metal production from levels now
possible with cooling methods using water. Its
applicability, except in special cases, is doubtful.
Noncontact Cooling of Molten Metal. Refined copper shapes
such as billets and cakes and partially refined copper
(anodes and ingots) are solidified by non-contact cooling
through the molds. This is also true for some copper alloy
ingot production. However, in both cases the current
practice requires that the metal be finally contact quenched
with additional water to permit handling at the end of the
casting line, and in addition, a small amount of water would
still be necessary for shotting operations. If only non-
contact cooling were employed, the quantity and types of
pollutants added to the cooling water would be reduced from
those added during contact cooling; however, all other
conditions remaining constant, the production rate would be
reduced from present levels. The effluent from non-contact
cooling can be recirculated with a minimum of treatment and
would require only makeup water and perhaps a bleed stream
to limit salt (dissolved solids) buildup that could plug
water passages. The pollutant loading would not be expected
to be different from those loadings determined for other
non-contact cooling operations or as makeup water for other
plant operations. Conversion to non-contact cooling
techniques would require increased water storage capacity
and recirculation capability, as well a longer or larger
casting line. The complete conversion of the entire
industry to non-contact cooling of metal appears not to be
practical since it would require extensive retrofitting.
Recirculation After Treatment. The practice of re-
circulating or reusing contact cooling water to reduce water
use and discharge is practiced to some degree by 94 percent
of the plants studied which discharge to POTW, and by 96
percent of the industry as a whole. The pollutant loadings
resulting from contact cooling cf molten metal are minor
relative to other process streams, and with solids removal
by settling and filtration, the water can be reused, with
makeup water being added to replace the amount evaporated.
The volume of the discharge can be reduced to no discharge
of process waste water or to very low levels, even in cases
where rainwater runoff enters the reservoir used to contain
the water. Eighteen plants in the industry, including one
plant which discharges other process wastewaters to a POTW,
do not discharge wastewaters from this operation.
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A cooling tower or sprays may be necessary for cooling the
hot cooling water before recycle. Alternative 4 in Figure 4
illustrates the practice of Plant C, which prior to 1974
discharged all cooling water to a POTW and now completely
recycles its cooling water. This plant also uses a
centrifuge to further dewater the sludges from the system
prior to their disposal.
Another simpler alternative is a variation of alternative 1
which is particularly adaptable tc plants with only weekly
or monthly discharges to POTW during periods of tank
cleanout. Plant 19, which previously discharged 9000
gallons of water from an ingot quench pit to a POTW to
remove sludge from the pit, constructed a temporary storage
tank to hold this water while the quench pit is cleaned.
Upon completion of the pit cleaning, the temporarily stored
water is recycled for metal cooling. As a result, this
plant now discharges no process waste water from this
operation, although other process waste waters from the
plant are discharged to a POTW.
Experience with total recycle systems for metal cooling
water indicates that no blowdown is necessary to reduce
salts and dissolved solids as these impurities form a scale
on the quenched metal and are thereby removed.
Control alternatives illustrated in Figure 4 as Alternatives
5 and 6 (with slight variations) are used by six of the
twelve plants visited in a 1973 EPA study of the entire
secondary copper smelting industry (secondary copper
effluent limitations guidelines development document, Ref.
1). The most sophisticated installations required for reuse
are storage pond and cooling tower capacity, associated
plumbing, sand filters, a reservoir, and capability for
backwashing of filters. Maintenance would primarily be in
the area of sludge removal every six months. Pump and
filter maintenance requirements are claimed to be
negligible. The advantage of Alternative 6 is that in the
event of flooding due to heavy rain, the discharge would be
one that is settled and filtered. Ordinarily no water is
discharged from the closed circuit. The system, being an
end-of-pipe type of treatment for mixed process waste waters
which upgrades the water for reuse, is suited for treatment
of waste water from slag granulation, slag milling and
classifying, and noncontact cooling as well as that from
contact cooling of molten metal.
102
-------
Identification of Treatment Alternatives
The waste water from the contact cooling of molten metal may
require pH adjustment to reduce the metals in solution.
This holds true for once-through and recirculated water use.
Although the pH of this stream will often be near the pH
range necessary for optimum metals removal, any adjustment
of pH can come from the addition of an alkali, such as
sodium hydroxide or lime. The water may also increase in pH
if waste water from slag granulation is combined with the
contact cooling water, because of the hydrolysis of some of
the constituents of the alkaline slag generated during
fluxing. In copper alloy production, ash left after
charcoal placed on the ingot has turned away also hydrolyses
to increase the pH of the cooling water.
Secondary copper smelters discharging contact metal cooling
water to POTW do not currently treat this stream prior to
discharge, aside from any settling that may occur in quench
pits. Therefore, no sampling data is available to
accurately characterize alternatives specifically at these
plants. However, certain data is available from direct
dischargers (Table 24) which show order of magnitude
reductions in loadings for Alternatives 3, 4 and 5 from
treated waste streams at three direct dischargers as
compared to the untreated discharge from this process at an
indirect discharger, Plant 12.
The effectiveness of Alternative 2, which employs primary
solids removal only, can be estimated by examining the raw
waste data discussed in greater detail in Section V. This
data is presented in Tables 13 through 15. In each case,
samples were taken immediately following the quench pit, so
some coarse settling had occurred in the pit prior to
sampling. This data shows that the pretreatment control
levels for cadmium and oil and grease are attained, and that
further treatment (pH adjustment) is required only for the
reduction of copper concentrations.
In addition, waste water streams generated by molten metal
cooling processes at secondary copper smelters discharging
to POTW are similar in chemical nature to process waste
water streams from other metals-based industries,
particularly electroplating and primary copper smelting and
refining. Extensive experimental and empirical data on the
effectiveness of neutralization and precipitation technology
on waste streams carrying metals is presented in detail in
the development documents for effluent limitations
guidelines and standards for these two industries (Ref. 17,
18 and 16, respectively). Although the relatively high pH
103
-------
TABLE 24 . EFFECTIVENESS OF TT1E TREATMENT ALTERNATIVES FOR
VZASTE WATIP. FROM MOLTEN !-TTAL COOLIHG
(Industry-wide 1973 data)
Loading, kg/kkg metal produced (or lb./
Treatment Alternative 1000 Ib)
Pollutant
Parameter
Susp. solids
Cadmium
Copper
Lead
Mercury
Nickel
Zinc
PH
1 3
Plant Plant Plant
12 V Y
1.69 0.012 0.171
(a\ (k\
NF^ ' NLCV ' NLC
0.010 0.001 0.004
0.034 0.006 0.0053
NF NR NR
NF 0.0002 0.002
0.007 0.0007 0.022
8.5 7.9 8.9
4 5
Plant Plant
H ¥
0,126 0.0056
NR(c^ 3 x 10"7
0.0028 1.7 x 10"5
0.0042 4,4 x 10"6
NR 6 x 10"9
0.00021 NR
0.0078 7 x 10"6
8.3 8.9
(a) NF = not found.
(b) NLC = no loading calculable.
(c) NR = not reported in analytical data.
104
-------
levels usually found in molten metal cooling waste water
streams from secondary copper smelters may obviate the need
for pH adjustment in some cases, the levels of reduction of
metals that are achieved in the electroplating and primary
copper industries by this technology should also be
achievable by secondary copper smelters, by virtue of the
chemical similarity of process streams between these
industries.
Waste Water From Slag Quenching and Granulation
Slag covers on reverberatory cr rotary furnaces are
generally raked off before the furnace is tapped. This slag
will contain a variety of materials including rasorite (a
borax flux), soda ash, lime, silica sand, and up to about 30
weight percent copper or alloy. The slag will also contain
significant quantities of copper, which can be economically
recovered.
At Plant 11, the only plant discharging to a POTW that
performs this operation, the copper-rich slag from the
reverberatory furnaces is charged directly to a cupola
furnace along with other residues. A molten alloy of copper
is produced by the cupola furnace which is then recharged to
the reverberatory furnaces. The depleted (waste) slag from
the cupola furnace operation is raked from the furnace and
quenched by dumping the slag directly into a granulation
pit. At this facility, the cupola is only operated
intermittently during the year, and thus depleted slag
granulation is also an intermittent operation. Slag
granulation water is periodically discharged to a POTW with
no further treatment, although some settling occurs in the
granulation pit.
The waste water from both copper-rich slag granulation
(which is performed by some direct dischargers) and depleted
slag granulation contains some fine solids of the granulated
slag and part of the soluble constituents of the slag.
Normally the pH of the waste water is between 8 and 10 due
to hydrolysis of the basic metal oxides present in the slag.
Of the seventeen plants which discharge to a POT -i, only one
uses water to quench and granulate slag. The remaining
copper alloy producers either air cool slags or ship them in
the form of cast slag pots to large scale processors, who
treat the material for metal recovery in cupola or blast
furnaces. The depleted molten slags from these latter
recovery operations may, however, be subsequently granulated
with water. Plant 18 recovers copper values from its
105
-------
No plants discharging to POTW perform slag milliner and
classification, so treatment and control technologies^ for
waste waters produced by this operation will not be
discussed in this document.
The current control and treatment technology alternatives
iSuaSftP* Wat? fr°m SlSg *uenching and9granulation Ire
illustrated in Figure 5. Alternative 2, which represents
pracScP °of ^H Wat6r after Pr±mary solids reSova?rS ?te
practice of the one plant discharging to a POTW
Alternatives 3, 4, and 5 illustrate varying degrees of
treatment and control technology for solSs ?emova?f
Alternative 1 represents no treatment of wastewaters but
rather heaping the slag slurry on a pile with ?hl wasS
conL. J^S1;? Jhr°Ugh the P±le- The «a?er is ?£n
c^f6*^ /^charged. M1 °f the Alternatives will, in
rlcjcle. WaSte Wat6r t0 a quality suitable for
Identification of Control Alternative
The amount of waste water generated in slag quenching and
10n Ca
anSoh10n HCan bS r€dUCed With *ecirclation Such an
approach is being employed by direct dischargers. The use
Wr ° granulate Sla9s to make them easier to handle
ne
atoor *1SfP°**1 m?re Convenient could be eliminated
^io?gS „ -the SlagS were counted in slag pots and
cooled in the air Those slags with high levels of solJd-
metal value would then have to be crushed so that they can
be charged into hammer mills or directly into ball milS ?or
wet milling operations. A lesser amount of crushing will be
required if the slag is to be charged into a cupola or bias?
|ir Cooling and Mechanical Size Reduction (Copper-Rich
biagj.. A common practice used by most copper allov
producers to eliminate the use of water is to collect thS
c-
coec
copper-rich slag in inverted cone-shaped thick metal pots
about one meter (1.1 yard) or larger in diameter. The slag
is cooled in the pot without the use of water and is
eventually transported in the pot to the copper-rich slao
storage pile, where it is dumped/ slag from ?his pile il
also treated to reclaim the copper values either by the
106
-------
Water Source
sue
QUENCH
AKD
CRANUUTION
1
Di* charge
sue
QUENCH
AND
CRANUUTION
PRIMARY
SOLI DS
REMOVAL
i
Sludge
\
1
sue
QUENCH
AND
GKANUUTION
sue
QUENCH
AMD
URANUUTION
nrknr
MIXED
PHOCESS
KATER-
RESERVOI8
PRIMARY
SOLIDS
fiFVOWL
i
Proccu 1
Water j[
MIXED
PROCESS
^_ Other Process WATER-
*ater PRIMARY
"* SOLIDS
.l&dg. Sludge* REMOVAL
Backwash
l_
— <
to>
l
i
i
sue
QUENCH
AND
GRANULATION
l
PRIMARY
SOLIDS
REMOVAL
i
Sludge
Recycle Water Recycle Water Bleed Recycle Water
Or Or
DUcharge Discharge
Or
COOLINC
TOWER
i
Slowdown Recycle
Kscharge
Water
Or
Discharge
Fioure 5. Current cx>ntrol aixT tr^atnent
for v.-aste water frcs^ rO -•••:.
alterratives
ard oranulaticn.
-------
smelter or it is sold to another secondary copper smelter
for reclaiming. Therefore, the use of air cooling followed
by mechanical size reduction as a control alternative to
copper-rich slag quenching would seem warranted.
Air Cooling and Mechanical Size Reduction (Copper-Poor or
Depleted Slag). Another source of slag is generated byth^
industry. This slag, which is copper-poor, is generated by
some smelters that reclaim the metal content of their own
slag and purchased copper. This is done by melting the slag
along with other copper-base scrap and residues in a cupola
or a blast furnace. The copper-rich slag, which is
relatively friable, is crushed and screened and the fines
pelletized. The coarse chunks and the pelletized slag are
charged into the cupola or blast furnace. The charge is
melted and two products are tapped, a copper alloy and a
waste or depleted slag that contains 1 to 2 percent copper.
The waste slag is normally granulated with water spray.
Waste water from depleted or waste slag quenching and
granulation could be completely eliminated by collecting
this molten, depleted slag in inverted, cone-shaped, thick
metal pots while it is being tapped from the furnace. The
slag would be cooled in the pots, transported in the pot to
the waste slag pile, and dumped. It should be noted that
none of the plants visited handled their depleted slags from
cupolas or blast furnaces in slag pots. Depleted slags are
usually granulated with water to make them easier to
transport and handle. In this form they have more end uses
than just landfill. In addition the granulated slags may be
easier to dispose of as ballast or fill than the large
chunks formed in slag pots. Therefore, the use of air
cooling and mechanical size reduction as an alternative to
depleted slag granulation is not warranted.
Recirculation After Treatment. Recirculating waste water
from slag quenching and granulation after treatment for
solids removal is practiced by all of plants in the industry
presently granulating slags. There are variations in the
extent of solids removal and the need for discharge. These
are discussed in more detail in the treatment alternatives
section that follows. Of the control and treatment
alternatives given in Figure 5, Alternative 3 provides a
means of treating all of the waste water for total recycle.
Solids are removed by settling before the water is recycled
for reuse for slag granulation and other processes. This
treatment alternative was discussed in detail in a previous
section dealing with contact cooling waters, in this case,
dissolved solids and salts buildup in slag granulation water
is prevented as these materials either form a scale on the
108
-------
slag prior to disposal or are effectively bled off via the
small amount of water that accompanies the slag as it is
discarded.
Identification of Treatment Alternatives
The waste water from molten slag quenching and granulation
requires treatment to reduce suspended solids and associated
metals. The pH of the waste water has been found to be
between 8 and 10, which aids in the removal of the soluble
metals. In most operations, the pH reaches an equilibrium
value due to hydrolysis of basic metal oxides and salts in
the slag. In mixed process waste water operations,
sufficient reaction occurs to maintain a pH near 8.5 for the
mixed stream. If needed, the pH of the mixed process waste
water may be adjusted with lime or caustic.
The various solids removal technologies are presented in
Figure 5. Plant 11 currently practices a modified form of
Alternative 2, in that the make-up water to the slag
granulating system comes from contact metal cooling
operations elsewhere in the plant. Alternative 2 is the
dominant practice of the industry. The effectiveness of
this treatment alternative can be estimated by examining the
raw waste data presented in Table 17. This data was
developed from samples taken from a slag quenching pit at
Plant 11, so that some settling of coarse solids had
occurred in the pit prior to the sampling point. No other
data characterizing the effectiveness of treatment
alternatives 3, 4 and 5 in Figure 5 are currently available.
Waste Water from Furnace Exhaust Scrubbing
The dusts, smoke, and fumes formed in the furnace operations
used by secondary copper or copper alloy smelters must be
removed from the furnace exhaust before being discharged to
the atmosphere. Cupola and blast furnace operations produce
large quantities of particulate matter from dusty charge
materials, such as fine slags and from coke ash. Emissions
are also produced from the combustion of coke and organic
wastes in the charge materials. Metal oxide fumes are
produced from zinc, lead, or other volatile metals present
in the charge materials.
Reverberatory and rotary furnaces produce some smoke,
especially if the charge contains organic waste materials or
when green-wood poles are inserted to deoxidize the bath.
Particulate emissions are produced during the charging of
fine slags or fine flux materials. Metal oxide fumes are
also produced from zinc, lead, or other volatile metals
109
-------
present in the charge materials. Phosphoric acid forms in
the scrubwaters for furnaces refining phosphor copper, which
produces an acidic waste water from these scrubbers.
Emissions from converters contain metal oxides of all of the
metals present, including some copper oxide and the oxides
of sulfur, phosphorus, or other nonmetals present in the
original bath of metal. Emissions from furnace operations
are usually directed to individual exhaust cleaning
equipment, although more than one furnace exhaust may be
treated by a single emission control facility.
A considerable amount of zinc oxide and some lead oxide fume
is formed during pouring of trass or bronze alloys that
contain these volatile metals. This fume is generally
collected along with the combustion exhaust gases and
directed to the furnace exhaust cleaning equipment,
Three of the seventeen secondary copper plants discharging
to POTW employ wet scrubbing of furnace emissions
exclusively (Plants 5, 12, 14). Three other plants (Plants
11, 18, and 19) employ a combination of wet and dry
emissions controls.
Identification of Control Alternatives
The amount of waste water generated during wet scrubbing of
exhausts from furnace-related operations and the loadings of
pollutants can be reduced by recirculating treated waste
water. Such an approach is currently being used by plants
employing wet scrubber systems. To eliminate the discharge
of waste water from furnace exhaust emission control
devices, dry air pollution control devices such as baghouses
or electrostatic precipitators are used. Over 50 percent of
the entire secondary copper smelting industry employs such
dry emission control methods exclusively. The solids
collected from exhaust cleaning consist primarily of metal
oxide fumes such as zinc oxide and lead oxide and are sold
or used for their metal content. Therefore, efficient
recovery of particulates in the exhaust gases provides some
return on investment in emission ccntrcl devices.
Dry Air Pollution Controls. The most common dry air
pollution control system is a fcaghouse. The gases are
cooled either by dilution with air, by water cooling of the
hot gas ducts, or with water sprays inside of the ducts.
The exhaust, before it is filtered, must be cooled to below
the ignition or fusion point of the bags. The ignition
point of the bags varies with the type of fabric used to
make them. Cotton or wool bags have the lowest operating
110
-------
temperature and glass fiber bags have the highest operating
temperature. Cooling water used on the outside of the ducts
is generally recycled. Water sprayed inside of the ducts
for cooling the exhaust must be completely converted to
steam to prevent blinding of the bags.
At least six of the forty-six smelters in the industry use
electrostatic exhaust cleaning systems to reduce emissions.
These are in addition to either baghouse or wet scrubber
control systems. No waste water should be generated in the
operation or for cleaning of electrostatic precipitator
emission control devices.
Metal oxides, especially zinc oxide, are very small in
particle size (less than 1 micron) and removal from
baghouses can be an extremely dusty operation. The dust
level during gathering and loading for shipment is reduced
by agglomeration with very small amounts of water. For
plants studied, the use of dry air pollution control
systems, despite the dust problem, has been a very effective
way to reduce emissions without the need for a waste water
discharge.
Wet gas scrubbers selected by secondary copper smelters
often of the high-energy venturi type. These scrubbers
have a pressure drop of about 0.123 atm (50 inches of
water), and remove 90 to 99 percent of the entrained solids.
Most of the solids are removed from the water with
thickeners and filters, and the water is discharged to
storage. The sludge recovered from brass and bronze
operations contains over 50 percent zinc as zinc oxide and
may be sold to zinc smelters. The sludge recovered from
exhaust scrubbers used by copper smelters contains about
four percent copper and is usually recharged into the
furnaces or stored for possible future recovery of the
values by the same company or by other smelters. Water
discharged to a pond or settling tank from a thickener will
contain appreciable amounts of solids (of about the same
composition on a dry basis as the sludge removed) and
soluble constituents. The soluble constituents will include
most of the soluble salts in the feed water plus the
addition of the soluble constituents in the exhaust gases.
The soluble constituents contributed by the process when a
cover flux is used are mostly borax and its metal-borate
reaction product or soda ash. Hydrolysis of such materials
increases the pH of the scrubber waste water.
Organic residues, soldering fluxes, various plastics,
especially polyvinyl chloride, etc., in the scrap material
oxidize in the furnace to produce water soluble constituents
111
-------
that lower the pH of the scrubber waste water. Therefore,
depending on the specific plant1s method of scrap
preparation and smelting, the exhaust scrubber waste water
may require pH adjustment by the addition of caustic or
lime. Waste waters with pH values between 8 and 10 are
recycled, which assures removal of soluble metals during
solids removal steps in the treatment of the recycle water.
The large volumes of water necessary to operate wet
scrubbers make it economically necessary to recirculate the
water. Treatment for solids removal provides a sludge of
primarily metal oxides (zinc oxide and lead oxide) that has
some market value and is dust free. After most of the
solids are removed by a thickener and a filter or
centrifuge, some form of settling is always used. Cooling
towers are used when the volumes of water are large. The
amount of water added to the operation replaces that lost by
evaporation and in the dewatered sludge. All six plants
discharging to POTW that use wet scrubbers partially recycle
the waste water from the scrubbers after treatment for pH
adjustment and for solids removal. The discharge from the
treatment is either recycled directly to the scrubber or it
becomes part of the mixed process waste water that may or
may not be recirculated. Control of salts and dissolved
solids buildup is usually controlled by bleeding a small
stream of water from the system and using it for makeup
water to the metal cooling circuit or by discharging it to a
POTW.
Alternative technologies currently being used for treatment
and control of scrubber waste water by the industry
(including direct dischargers) are illustrated in Figure 6.
They range from solids removal and discharge to closed loop
circuits of process or mixed process waste water. The
technologies indicated are discussed in more detail below.
Identification of Treatment Alternatives
The waste water discharged from wet scrubbing devices used
to control emissions contains suspended solids, dissolved
metals, and some oil and grease from the exhaust of furnaces
used for smelting operations. Before discharge or reuse of
the water, the solids must be removed and the amount of
metals reduced, primarily by pH adjustment and the removal
of suspended solids by settling. The pH of the waste water
must usually be adjusted with caustic or lime to counteract
the effect of acid formation by the contaminants charged
with the metal scrap, particularly in connection with the
production of phosphor copper. In some cases where pH
adjustment is riot used, the waste water attains a high pH
112
-------
Water Source
— «.«.
SCRUBBER
PRIMARY
SOLIDS
REMOVAL
t
slu
Discharge
£c
-* — gases ( "*~- gases
SCRUBPKR
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t
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PRIMARY
SOLIDS
REMOVAL
i
slud
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[
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ENTRAISMCNT ' ' ENTSAI\-KtNT
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Figure 6. Control and treatment alter-
natives for furnace exhaust
scrubwater
-------
from the alkaline flux carried from the furnace by the
exhaust.
The treatment technologies that are currently being used by
the industry (including direct dischargers) to remove solids
and dissolved metals are illustrated in Figure 6. All six
plants discharging to a POTW discharge water from emission
scrubbing operations partially recycle the scrubwater after
treatment for solids removal (Alternative 2). In two cases
the pH is adjusted, but in both_cases, -adjustment is
performed by periodically adding caustic to a small settling
pit without mixing. Good pH control in scrubwater effluents
was not observed at these two plants.
Table 25 presents analytical data developed by sampling
teams for waste water generated by scrubbers on phosphor
copper melting furnaces. Some metals removal is
demonstrated, but levels remain high due to the low pH's
observed.
Tables 26 and 27 show the values obtained by sampling teams
for settling treatment of anode furnace and billet furnace
scrubwaters at Plant 5 (utilizing Alternative 2 in both
cases). The effluents from these two settling operations
show high metals loadings, which is attributed to the lack
of pH adjustment and inadequate retention times.
Table 28 presents data collected from a pH adjustment and
settle operation employed at Plant R on a waste stream which
is similar in character to the wastewater generated by
furnace exhaust scrubbing operations. Table 28 compares
this data to data collected at Plant 5 which uses
Alternative 2. This data indicates that lime or caustic
treatment followed by settling is a more effective means for
reducing concentrations of metals, and produces an effluent
of high quality.
Data on the effectiveness of the various alternative
technologies for the reduction of pollutant parameters is
available from other plants in the industry. Two plants
which practice Alternative 6 in Figure 6 were sampled at
various points in the process, thus yielding information on
successive steps in solids removal and a characterization of
raw waste water as it left the scrubber. Plant E, an
unalloyed copper producer, and Plant V, a copper alloy
producer, were chosen. The concentrations of selected
pollutants at various sample points in the process are given
in Tables 29 and 30, respectively. From this information
(and waste water flows and the daily production of molten
114
-------
TABLE 25. PHOSPHOR COPPER FURNACE SCRUBWATER BLEED PRETREATMENT WITH
CAUSTIC, SETTLING AND DISCHARGE TO POTW - PLANT 11
PARAMETER
PH
TSS
Oil and Grease
Pb
Cu
Cr
Ni
Zn
Cd
Sb
Hg*
B
PRETREATMENT INFLUENT <""
CONCENTRATION
(mg/l)
1.6 *
19
3
9.43
19.7
0.07
0.06
30.6
0.133
0.2
< 0.0005
< 0.02
WASTE LOAD
kg/MT
—
0.080
0.01
0.040
0.083
0.0003
0.0003
0.13
0.00056
0.0008
< 0.000002
< 0.00008
Ib/short ton
_
0.16
0.02
0.080
0.17
0.0006
0.0005
0.26
0.0011
0.002
< 0.000004
< 0.0002
PRETREATMENT EFFLUENT <1)
CONCENTRATION
(mg/l)
4.9 *
5
2
3.95
9.1
0.07
0.06
9.7
0.053
<0.2
< 0.0005
<0.02
WASTE LOAD
kg/MT
—
0.02
0.008
0.017
0.038
0.0003
0.0003
0.041
0.00022
< 0.0008
< 0.000002
< 0.00008
Ib/short ton
—
0.04
0.02
0.033
0.076
0.0006
0.0005
0.081
0.00045
< 0.002
< 0.000004
< 0.0002
1 AVERAGE OF 8 SAMPLES COLLECTED OVER 2 DAY PERIOD
» pH UNITS
AVERAGE OF 4 SAMPLES COLLECTED OVER 2 DAY PERIOD
-------
TABLE 26. SETTLING TREATMENT OF ANODE FURNACE SCRUBWATER BLEED - PLANT 5
PARAMETER
PH
TSS
Oil and Grease
Pb
Cu
Cr
Ni
Zn
Cd
Sb
B
PRETREATMENT INFLUENT*1'
CONCENTRATION
(mg/l)
7.10*
1050
<1
387
138
052
2.51
167
5.77
2.1
2.30
WASTE LOAD
kg/MT
—
4.0
< 0.004
1.5
0.52
0.0020
0.0095
0.63
0.022
0.0080
0.0087
Ib/short ton
8.0
< 0.008
2.9
1.0
0.0040
0.019
1.3
0.044
0.016
0.017
PRETREATMENT EFFLUENT (1)
CONCENTRATION
(mg/l)
7.10*
42
<1
21
40.6
0.08
2.34
56.3
4.79
0.4
1.75
WASTE LOAD
kg/MT
_
0.16
< 0.004
0.080
0.15
0.0003
0.0089
0.21
0.018
0.002
0.0066
Ib/short ton
_
0.12
< 0.008
0.16
0.31
0.0006
0.018
0.43
0.036
0.003
0.013
(1)SAMPLES TAKEN AFTER SETTLING OF COARSE SOLIDS AND PRIOR TO FURTHER SETTLING IN A LARGE POND
AVERAGE OF 7 SAMPLES OVER 2 DAY PERIOD.
» pH UNITS
-------
TABLE 27. BILLET FURNACE SCRUBWATER BLEED SETTLING AND
DISCHARGE TO POTW PLANT 5(1 >
PARAMETER
pH
TSS
Oil and Grease
Pb
Cu
Cr
Ni
Zn
Cd
Sb
Hg
B
PRETREATMENT INFLUENT
CONCENTRATION
(mg/l)
6.90«
116
-
6.62
72.0
0.24
0.04
5.08
0.23
10.2
0.032
0.73
WASTE LOAD
kg/MT
—
0.20
—
0.011
0.12
0.0004
0.00007
0.0086
0.0004
0.017
0.00005
0.0012
Ib/short ton
—
0.38
—
0.022
0.24
0.0008
0.0001
0.017
0.0008
0.034
0.0001
0.0024
PRETREATMENT EFFLUENT
CONCENTRATION
(mg/l)
7.00*
157
—
8.81
85.5
0.24
0.04
6.74
0.26
2.5
0.016
0.6
WASTE LOAD
kg/MT
0.27
0.015
0.14
0.00041
0.00007
0.011
0.00044
0.0042
0.000027
0.001
Ib/short ton
0.52
— _
0.029
0.28
0.00079
0.00013
0.022
0.00086
0.0082
0.000053
0.002
m
SAMPLES TAKEN AFTER SETTLING OF COARSE SOLIDS AND PRIOR TO DISCHARGE TO POTW.
24 hr. COMPOSITES
pH UNITS
-------
TABLE 28 EFFECTIVENESS OF TREATMENT ALTERNATIVES FOR
SECONDARY COPPER FURNACE EMISSIONS SCRUBWATER
PARAMETER
pH
TSS
Oil & Grease
Cd
Cu
Pb
Hg
Ni
Zn
B
SETTLING (PLANT 5)
Before
Treatment
(mg/Jt)
7.1
1050
<1.0
5.77
138
387
NR
2.51
167
88
After
Treatment
(mg/t)
7.1
42
<1.0
4.79
40.6
21
NR
2.34
56.3
67
%
Removal
-
96
-
17
71
95
-
7
66
24
TREATMENT WITH LIME
AND SETTLING (PLANT R)*
Before
Treatment
Img/Jl)
1.75
25
2.8
0.040
38.40
22.9
0.001
94.5
1280
0.80
After
Treatment
(mg/t)
8.3
1.3
4.1
0.015
0.160
0.060
< 0.001
1.13
2.28
0.76
%
Removal
—
95
-
62
99.5
99.7
-
99
99.8
5
Company data. Wastewater includes emissions scrubwater from
precious metal smelting.
118
-------
TABIE 29 RESUIJS OF SAMPLING WASTE WATER FRCM
FUFNACE EXHAUST SCRUBBIBG, COMPANY E
(DIRECT DISCHARGER)
Wastewater Discharge
From Hydroclone.
mg/1
Parameter
Susp. solids
Cadmium
Copper
Lead
Mercury
Nickel
Zinc
Oil and Crease
PH
High
822
2.789
0.165
0.742
0.00022
0.028
7.460
<1
9.04
Low
527
0.238
0.048
0 216
<0. 001
0.016
0.497
<1
• 7 63
Avg
CM
680
1.514
0.107
0.479
0.00011
0.022
3.979
<1
8 3-t
Wastewater Discharge
From Thickener
Concentration, mg . 1
High
331
2 579
0.055
0.284
0.00108
0.022
13.428
<1
-.63
Low
223
1.737
0. 023
0. 186
.
(c) Flow estimated to be the same as the discharge (ht 5.700 00" 1 day
(d) now 175 gpm or 964. OM) 1 day.
(e) Flow 175 gom or 95-4.000 1, day-
(0 Flow 222. 000 gpd or 840. 000 I/day.
-------
TABLE 30 . RESULTS (F SAMPLING WASTE WATER FRCM FURNACE EXHAUST
SCRUBBING, AND MILLING AND CLASSIFYING SLAGS, COMPANY V.
(COMPLETELY RECYCLES ALL PROCESS WASTE WATER)
NJ
Wastewater Discharge After Wastewater Discharge After
Thickener and Centrifuge. Thickener, Centrifuge, and Settling.
mg/1 rng/1
Parameter High Low Avg High Low A\g
(h)
-------
metal) average loadings for each sampling point were
determined.
In Plant E, the raw waste water characteristics had to oe
taken as the sum of loadings observed in a quench circuit
thickener discharge and a scrubber hydroclone discharge
because both were involved in removing solids from the
emission. The quench circuit operated as a closed circuit
with no discharge of waste water except for that removed
with the sludge. In Plant V, the raw waste water was
sampled at a thickener discharge just after the scrubber
operation.
Effectiveness of Alternatives 2, 4, 5 and 6 for the
reduction of suspended solids, copper, lead, zinc, and oil
and grease are indicated in Table 31. A progressively lower
loading in suspended solids is observed as the level of
technology increases in sophistication. There is also a
reduction in copper, lead, and zinc loadings and an
accompanying reduction in loadings for cadmium, lead,
mercury, and nickel. The effectiveness of extended settling
periods in lagoons (Alternative 6) is obscured because of
the mixing of waste water from other processes. For Plant
V, the effectiveness of one or three lagoons is presented
under Alternative 6 as Plant V-1 and Plant V-2,
respectively.
It should be pointed out that under Alternative 6, the pH of
the recycled water is about 7 for Plant V-1, while that of
Plant E is about 8. This lower pH might explain the higher
loadings for copper, lead, and zinc for Plant V-1, even
though the suspended solids removal is less.
In addition, waste water streams generated by exhaust
scrubbing processes at secondary copper smelters discharging
to POTW are similar in chemical nature to process waste
water streams from other metals-based industries,
particularly electroplating and primary copper smelting and
refining. Extensive experimental and emperical data on the
effectiveness of neutralization and precipitation technology
on waste streams carrying heavy metals is presented in
detail in the development documents for effluent limitations
guidelines and standards for these two industries. The
levels of reduction of heavy metals that are achieved in the
electroplating and primary copper industries by this
technology should also be achievable by secondary copper
smelters by virtue of the chemical similarity of process
streams between these industries.
121
-------
T7J3LE 31. EFFECTIVLICSS OF TREATMENT ALTERNATIVES
FOR IC\STE WATER ET5QM ",v1ET SCRUBBING — DIRECT DISCHARGERS
NJ
Loading, kg/kkg metal
Produced (or ID/lOOU
ID metal)
Treatment Alternative
Parameters
Susp. solids
Cadmium
Topper
Lead
Mercury
Nickel
Zinc
Oi 1 & grease
pll
(a) Plant E
(b) Plant V
1
Plaut
E(a)
128.5
0.289
0.029(c)
7xlO"5
L.024
0
7.62
Alternative
Alternative
Alternative
Alternative
Alternative
Alternative
245
Plant Plant Plant Plant
V (b) E (a) V (b) E (a)
7.521 66.6 4.22 0.779
0.006 0.002 0.002 0.001
0.548 0.001 0.476 0.001
3.565 0.009 1.263 0.009
IxlO"6 6xlO"5 IxlO-7 2xlO-6
0.006 0.0002 0.004 0.0003
2.971 0.016 1.776 0.003
0.321 0.053 0.133 0.034
7.1 8.96 7.03 9.40
6
Plant Plant
V-l(b) E (a)
0.113 0.568
0.002 0.002
0.005 0.001
0.007 0.003
l.SxlQ-6 2xlO"5
0.0002 0.0004
0.181 0.0142
0.007 0.002
6.97 8.30
Plant
V-2(b)
0.050
0.0001
0.018
0.004
1.5xlO"6
0.00015
0.009
0.016
7.7
1 Sampling after quencher plus after hydroclone
2 Sampling after hydroclone
5 Sampling thickener and centrifuge overflow
6 Sampling of lagoon mixed process wastewater, partial discharge
1 Sampling after thickener
4 Sampling after centrifuge
Alternative 6-1
Alternative 6-2
i l_Ji —
Sampling after one pond
Sampling after 3 ponds, mixed process wastewater,
no discharge
(c) Cross loading.
-------
Waste Water from Electrolytic Refining Operations
Electrolytic cells in tank houses electrolytically refine
anode copper into high purity cathode copper. The
electrolyte solution consists of demineralized makeup water,
copper sulfate, and sulfuric * "acid. Normally, the
electrolyte solution is continuously circulated through
thickeners and filters to remove the solids (slimes) and
recycled back through the electrolytic cells. The cells
operate hot so that makeup water is required to replace the
amount evaporated. Most of the makeup water is generally
added during the daily washdown of the tops of the cells.
Waste water from electrolytic refining operations originates
from spills, cell maintenance and repair, and occasionally,
large-scale accidental losses. Depending on the quality of
the anodes and the impurities from the scrap metal that are
carried through the fire refining, soluble metal
concentrations build up in the electrolyte which cannot be
removed as slimes. When this occurs, a bleed stream of the
electrolyte is required. Such waste electrolyte normally is
treated to remove the copper content either by high-voltage
deposition or by cementation with iron. At one direct
discharger, the high nickel concentrations permit the
byproduct recovery of NiSO^ by means of barometric
condensers. The resulting solution may then be neutralized
and filtered before discharge. Seme electrolytic refineries
have a ready market for the contaminated electrolyte. Most
of the plants sell their slimes (for the precious metal
value they contain) to primary copper refiners or others
equipped for precious metal recovery. Plant A operates an
on-site precious metal recovery facility.
Makeup water, which must be low in total ion content, comes
from boiler condensate or demineralizing systems. The
backwash from ion-exchange resins used to treat boiler water
feed or backwash from demineralizers could in effect be
considered part of the waste water load of electrolytic
refining. However, these are considered to be boiler-
related operations and not process waste water from
secondary copper manufacturing.
The control and treatment technology alternatives currently
used by the industry for waste water from electrolytic cells
are illustrated in Figure 7.
Only one of the plants discharging to POTW uses electrolytic
processes. This facility (Plant 5) recovers the copper
values from the spent electrolyte by cementation with iron
123
-------
N«t«r Source
•»Backwash
DUcharf*
!ȣ! J
atment For ^»t.tco•• f'J
«-Upset»-Bl««d« » c--«;i«
Tr««t
Splllt-Upseta
-------
and discharges the barren solution to a POTW without further
treatment.
Identification of Control Alternatives
Unless a refinery has a market for waste electrolyte, there
is no viable control alternative other than to treat the
waste stream for copper recovery and to neutralize the acid
content. At Plant A, a direct discharger, the waste water
generated from the electrolytic refining of anodes contains
a buildup of nickel which allows an economical recovery of
nickel values by the evaporation techniques employed by
several primary copper refineries (i.e., recovery of nickel
sulfate). The amount of arsenic present in secondary
electrolyte solutions is negligible. The value of the
sulfuric acid alone does not warrant evaporation of the
spent electrolyte for acid value recovery after the copper
has been removed.
Copper is reduced in the bleed electrolyte by using
insoluble anodes and depositing the copper on cathodes.
Such recovered copper is recharged into anode furnaces.
Another method is to cement out the copper using scrap iron.
The copper is recharged into the copper smelting circuit,
usually at the converter or anode furnaces. The depleted
electrolyte is then typically treated before discharge or
reused. Electrowinning and cementation can also be used in
series for copper content recovery.
Identification of Treatment Alternatives
Figure 7 illustrates the treatment alternatives currently
being used by the industry. Plant H, which is the newest of
the electrolytic refiners, is capable of recycling
electrolyte for extended periods of time without a bleed
stream. Plants A and E (direct dischargers) and Plant 5 (an
indirect discharger) use a bleed stream to reduce
impurities. All remove slimes for eventual recovery of
precious metals.
The effectiveness of Alternative 3, which features pH
adjustment, mixing and thickening followed by sand
filtering, can be only estimated. The discharge from Plant
5, which is a mixed process waste water, was used as
representative of Alternative 1. The discharge of treated
waste water from Plant H, even though it is not continuous,
was chosen as representative of Alternative 3. The results
are given in Table 32. The apparent effectiveness of the
treatment for reducing loadings is influenced by the small
flows involved. However, even if the flows were an order of
125
-------
TABLE 32. Etl'ECTIVENESS OF TREMMENT AKTEFNATIVES FOR WASTE
WATER FROM EIECTROLYTIC REFINING — INDIRECT
& DIRECT DISCFxARGERS
Loading, kg/kke
metal produced
Treatment Alternative
Pollutant
Parameters
Suspended solids
Cadmium
Copper
Lead
Mercury
Nickel
Zinc
Oil & grease
PH
1
Plant 5 (.&)
3.334
NR«>
0.092
0.035
NR
0.061
0.127
NR
7
2
Plant ,HU»
0.0048
NLC
-------
magnitude greater, this treatment technology reduces
loadings significantly. Alternative 4, the byproduct
recovery of NiSCW by usage of barometric condensers,
produces no process waste water at Plant A. Well maintained
and highly efficient deintrainment pads are employed in the
condensers to minimize carryover. Except for Plant A,
slimes are sold. Plant A produces a very small volume of
process waste water during precious metal recovery (23 cu
m/day (6,000 gpd). Currently, part of this flow is
impounded in lined ponds and the remainder is discharged.
Waste water streams generated by electrolytic processes at
secondary copper smelters discharging to POTW are remarkably
similar in chemical nature to electrolytic process waste
water streams from other metals-based industries,
particularly electroplating, primary copper smelting and
refining, and secondary lead smelting and refining.
Extensive experimental and empirical data on the
effectiveness of neutralization and precipitation technology
on waste streams carrying heavy metals is presented in
detail in the development documents for effluent limitations
guidelines and standards for these industries (Ref. 17,
18 and 16, respectively).
Combined Waste Water Streams
No data on the efficiency of pollutant removal is available
for indirect dischargers who combine waste streams for
treatment. Data is available, however, for two direct
dischargers (Plants R and F). Plant R, which melts
virtually pure copper scrap into wire tar, recently (1973)
made a considerable investment for the reduction of
pollutants from smelting and related operations. Extensive
pipe segregation preceded the installation of a treatment
plant for pH adjustment (lime treatment and clarification)
and sludge removal. The number of process waste water
discharge pipes was reduced from ten to four. All of the
sanitation waste water is directed to one of these
discharges and eventually will be sent to a municipal
treatment facility. The processes discharging waste water
into the plant treatment facility are laboratory water,
127
-------
plant wash down, furnace exhaust gas cooling before (dry)
gas cleaning, and a chemical recovery system for precious
metals. Of an estimated 50,000 gpd discharge, 60%
originates from emissions scrubbing at a precious metals
recovery facility, 38% from wet scrubbing and cooling of
emissions from a secondary copper reverberatory furnace, and
2% from laboratory operations.
The treatment facility is shown schematically in Figure 8.
The industrial process water enters a polyvinyl chloride
(PVC)-lined, concrete surge tank. This tank evens out the
fluctuating inflow, allowing the level in the tank to rise
or fall while allowing the pumps to discharge a constant
flow to the mixing tanks. Agitation is also provided in
this tank to mix acid and alkaline incoming streams and
obtain some natural neutralization. The three transfer
pumps provide flexibility to handle varying flows while
maintaining sufficient capacity to handle excessive flow
conditions.
The waste water, of about pH 1.5, is pumped to the first
stage of three PVC-lined, concrete mixing tanks. A lime (3
percent calcium hydroxide) slurry or, alternately, caustic
(50 percent NaOH), depending on availability and cost, is
added to the first stage where the pH is brought up to 4.5.
The water then flows into the top of the third stage where
caustic is added to bring the pH up to 8.2. The water is
then "polished" in a rapid mix tank, a treatment consisting
of complete mixing and a final caustic addition to raise the
pH to 8.8 (considered to be the optimum precipitation
level). A solution of ferric sulfate is also added as a
coagulant. Facilities are also available for coagulant aid
(a polyelectrolyte solution) addition; however, this is not
presently employed. The rate of addition of lime or caustic
is automatically regulated by continuous pH monitoring with
feedback to proportional controllers on the caustic or lime
feed pumps for the various mixing tanks.
The neutralized water is then pumped to a centerflow
clarifier. The clarified water is collected in a circular,
90-degree V-notch, wired trough, and then flows to a tank
where the effluent is discharged. Concurrent with the
settling and clarification operations is an automatic
semicontinuous sludge dewatering process. Here, three
days/week for eight hours/day, the sludge is drawn off and
filtered on a rotary vacuum filter. The filter operates
with a three inch precoat of diatcmaceous earth. The sludge
is "cut" off the filter and falls into a hopper located
above a truck. The collected material, 35 percent solids,
128
-------
FROM
PLANT
GENERAL WASTE
SURGE TANK
(30.OOO GAL.)
NEUT. SYSTEM
NO.
EFF. METER
PIT
TO
ROTARY
VACUUM
FILTER
SLUDGE TO
SCAVENGER
Fioure 8.
P'P*" v?3Pt.c ••'•"-t
(Plant R)
t rer-, rr
-------
is trucked to an on-site landfill area. The filtrate is
collected and recycled to the rapid mix tank.
The entire plant is located in an area approximately 60 x
120 feet, with all the equipment except the clarifier
located indoors. An elaborate instrumentation room was
designed into the facility; from the control room all
operations can be monitored and most can be controlled
manually. EPA monitoring data of the effluent quality from
this treatment plant is presented in Table 33. The
effectiveness of this treatment system for removing a range
of pollutant parameters is presented in Table 34.
In another case, Plant F uses continuous recycle of its
mixed process waste water after settling and filtration.
The same system is employed to treat discharge from the
plant when rainwater exceeds that lost by evaporation in
various processes, and for this reason, the system can be
considered an end-of-pipe treatment.
"Dirty" process water from contact and non-contact cooling
operations and from slag quenching and milling is pumped to
a holding pond for settling, then pumped through three sand-
and-coal filters, and then stored in a concrete reservoir.
Makeup well water is pumped directly into the reservoir.
The filtered water and makeup water are then pumped to the
various water-using process steps. The filters are
automatically backwashed when the flow is restricted (once
every day or two). The backwash solids are sent to a small
holding pit and then pumped back to the settling pond.
(Backwash formerly went to the thickeners in the slag
milling and classification area when it was operating.)
Periodic cleaning of the pond (dredged once or twice a year)
removes these accumulated solids, which are sent to the
depleted slag piles.
Plant F normally does not discharge waste water, and for
this reason, no effluent characterization was available from
state or regional environmental agencies.
Treatment Technology for Oil and Grease
On April 22, 1975 EPA published a notice in the Federal
Register (40 FR 17762) requesting public comment on a
proposal to establish a pretreatment standard limitation of
100 mg/1 for oil and grease. Comments on this proposal have
been mixed and are still being evaluated; however, 100 mg/1
of oil and grease appears to be the most appropriate
limitation for introduction of this pollutant to a POTW.
Technology capable of achieving this level consists of
130
-------
TABLE 33 CHARACTERISTICS OF EFFLUENT FROM LIME TREATMENT AND CLARIFICATION FACILITY
COMBINED WASTE WATER STREAMS, PLANT R (CONCENTRATIONS IN mg/j)
Sampling
Period*
2/4/74-3/4/74
3/5/74-4/4/74
2/3/75-3/2/75
3/3/75-4/6/75
4/6/75-5/4/75
5/5/75-6/1/75
pH
Av.
8.5
8.9
8.7
8.9
8.6
8.9
Max.
_
-
-
-
9.0
9.0
Oil&
Grease
Av.
0.88
1.12
1.2
0.20
0.20
0.15
Max.
_
-
—
—
0.20
0.16
TSS
Av.
1.0
1.3
<1.0
<1.0
<1.0
<1.0
Max.
_
—
—
—
<1.0
<1.0
Fe
Av.
0.02
0.06
0.14
0.07
0.14
0.14
Max.
—
—
—
0.24
0.20
Zn
Av.
0.35
0.28
0.30
0.16
0.27
0.28
Max.
—
_
—
0.35
0.47
Ni
Av.
0.03
0.34
0.30
0.08
0.27
0.20
Max.
_
_
_
0.37
0.31
Pb
Av.
0.05
0.04
<0.05
<0.05
<0.05
<0.05
Max.
__
—
—
_
<0.05
<0.05
Cu
Av.
1.35
0.40
0.30
0.23
0.47
0.24
Max.
—
_
_
0.67
0.37
Source: EPA regional office
•Sampling was conducted 4 days in every 30 day period. Samples usually were 2 hour composites.
-------
TABLE 34 EFFECTIVENESS OF LIME TREATMENT AND CLARIFICATION
FACILITY - COMBINED WASTE WATER STREAMS, PLANT R
PARAMETER
TSS
AL
Ba
Cd
Cl
Cr/Cr+6
Cu
F
Fe
Pb
Mn
Mo
Zn
As
B
Hg
Ni
Se
Ag
Oil & Grease
COD
CONCENTRATION, mg/l
Raw Influent
(untreated)
25
0.50
0.51
0.040
1450
0.044/0.030
38.4
1.3
7.92
22.9
0.21
< 0.010
1280
< 0.001
0.080
0.001
94.5
<0.001
0.044
2.8
132
Effluent
(treated)
1.3
0.12
1.52
0.015
1130
0.003/0.003
0.160
1.3
0.10
0.060
0.020
< 0.010
2.28
< 0.001
0.76
0.001
1.13
< 0.001
<0.010
4.1
76
Source: Company Data
*Samples were taken on 1/9/75. Raw waste was a composite
of scrubber water from copper reverbatory furnace emissions
control and precious metal furnace emissions scrubber.
Treated wastewater was a grab sample of combined waste-
water after lime treatment and clarification.
132
-------
skimmers and grease traps, which have been widely used
throughout most manufacturing industries, notably the
secondary aluminum segment of the nonferrous metals
manufacturing industry. It should be stressed that the
levels of oil and grease found in the effluents sampled at
indirect dischargers were well below 100 mg/1, and thus no
treatment for this pollutant is projected for most such
sources, although levels exceeding 100 mg/1 have been found
in the past in the scrubwater from one direct discharger
(Plant V).
133
-------
SECTION VIII
COST, ENERGY AND NON-WATER QUALITY IMPACTS
Introduction
In Section VII of this report various control and treatment
technologies for limiting or eliminating the introduction of
process wastewaters into POTW have been presented.
Additionally, the compatability and treatability of these
wastes in POTW was evaluated in Section VI. This section
presents the capital and annual costs for applying various
technologies for the control and treatment of the following
process wastes:
Metal cooling water (ingot, anode, billet, and shot)
Slag quenching and granulation waste water
Furnace exhaust scrubbing waste water
Electrolytic refining waste water.
Control and treatment costs for slag milling operations,
which are performed by some secondary copper smelters, are
not presented since no plants which discharge to POTW
presently conduct these operations.
Separate cost estimates are given for large and small model
plants. Medium-sized model plants are also included where
medium-sized plants would be impacted by the levels of
control identified in this report. The costs of alternative
treatments and controls versus PCTfo pollutant loading or
reduction in concentrations are also presented in order to
compare the costs and benefits of alternative control and
treatment technologies.
Basis for Cost Estimation
The derivation of the investment and annual costs for
treatment processes employed in this industry is described
in this section. All costs are given in fourth quarter 1975
dollars but may be adjusted to any year basis by using
appropriate engineering cost indices.
135
-------
The following items have been taken into account in
preparing and presenting the cost of the alternative control
technologies:
Investment
Facilities
Equipment
Installation
Transportation
Contingency
Engineering
Land
Annual Costs
Amortization
Operation and Maintenance
Sludge/Slag Disposal
Energy
Materials
Taxes and Insurance
Each item is defined as follows:
INVESTMENT
Facilities. The types of facilities include concrete
settling and holding pits and buildings.
Holding and settling pits are constructed of 8-inch
reinforced base slabs and 16-inch walls. A general cost
estimating relationship was developed from Reference 1
resulting in a base slab cost of $20/m2 and a wall cost of
$300/m3 of concrete in place. The costs include setup and
layout, excavation, concrete, backfill and cleanup.
For example, the cost of a 6 m3 pit (3 x 2 x 1 m) is
computed as follows:
(3x2x$20) + (2x3x.4x$300) + (2x2x1. 4x$300) = $1,320.
Building costs are based on average factory costs presented
in Reference 3. A cost of $20/ft2 is used, which includes
site work, masonry, roofing, glass and glazing, plumbing,
heating, ventilating and electrical work. Buildings are
included for treatment processes which employ lime or
caustic soda neutralization. A standard sized structure of
220 ft2 is provided in all cases.
136
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Equipment. Certain types of equipment such as pumps,
piping, storage and mixing tanks are widely used in the
treatment processes applicable to the waste streams
generated by the secondary copper industry. Parametric cost
curves were developed for such items to facilitate the cost
computations. Individual costs were obtained for equipment
items with only very limited application.
Pumps. Costs of water and slurry pumps, including motors,
are shown in Figure 9 as a function of capacity. The costs
shown are for representative types of pumps and are based on
Reference 4. It is noted, however, that the types and sizes
of pumps required for a particular activity can vary widely,
depending on the characteristics of the material being
pumped and the height and distance the material must be
transported.
In the subsequent description of process costs, the number
of pumps assigned is shown as, for example, 3+1 or 4+2. The
first number indicates the number of pumps operating in the
system at a given time. The second number represents spare
or standby pumps assigned to prevent disruption in treatment
system operations.
Piping. Pipe costs, as a function of pipe diameter are
shown in Figure 10. The pipes are cast iron, class 150.
The pipe material costs are from Reference 1 and increased
by 20 percent to account for ancillary items such as
connectors, T's and valves.
Holding and Mixing Tanks. Tank costs shown in Figure 11 are
from Reference 5. The tanks are cf steel construction. The
costs of the agitators used in the mixing tanks are from
Reference 4.
Cooling Towers. The cooling towers costed in Figure 12 are
designed to cool water from 130°F to 90°F at 78° wet bulb.
The towers are packaged units. Costs are based on Reference
6.
Flocculant Feed System. The system consists of a tank, a
feed pump mounted under the tank, interconnecting piping
with relief-return system and stainless steel agitator. The
system design and cost are from Reference 7.
Tank Size Cost
50 gal. $1,600
150 gal. $2,035
500 gal. $3,500
137
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Figure 10 PIPE COSTS
110
100
90
80
70
cc
UJ 60
LLJ
8
o
50
40
30
20
10
10 20 30
PIPE DIAMETER -cm
40
50
139
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Figure 11 HOLDING AND MIXING TANK COSTS
100
-i 4-—J,—J,~4.-j~i
-i •!-—i———j--f-
!• f-— f—-(--- f--;"j"i
—j—"j— l--j"-f"i"f
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• TANKS | I I | i
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,v T i--t--t--r-t-i-
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i TANKS ! i i
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100
CAPACITY
140
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Figure 12 COOLING TANK COSTS
$8,000
7,000
6,000
5,000
4,000
0.5
1.0 1.5 2.0
CAPACITY m3/min
2.5
3.0
141
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Systems are selected for employment at plant operations
based on treatment flow requirements.
Lime Neutralization System. Lime neutralization systems
using hydrated lime are employed in a number of treatment
processes. The major system components are:
Lime Feeder
Lime Mix Tanks
Flash Mix Tank
Instrumentation, valves. Fittings
The lime feeder includes a mechanical vibrator and conical
bin. Its cost of $1,800 is from Reference 4. The sizes of
the lime neutralization units employed within the secondary
copper plants considered fall within a relatively narrow
range. The same feed is used with all systems.
The lime mix tanks are selected to hold a 1 week supply of
lime slurry stored as a 19 percent solution, 2 Ib/gal. The
flash mix tanks are generally sized for 10 minute retention.
The costs of the lime mix and flash mix tanks are obtained
from Figure 12. Instrumentation is estimated to cost
$5,000.
For example, consider a lime neutralization system required
to treat a flow of 760 1/min of wastewater with 0.32 kg of
hydrated lime per 1,000 1. A total of 760 1/min x 1440 min
x 5 days (5,470 m3) of wastewater must be treated each week
using 1750 kg (0.32 kg/m3 x5,470 m3) of hydrated lime.
Mixed as a 19% slurry, this requires 7,293 1 (5,470 m3 x
0.32 kg/m3 divided by 0.24 kg/1) of lime slurry storage
capacity. The flash mix tank, sized for 10 minute
retention, has a capacity of 7,600 1 (10 min x 760 1/min).
The resultant system cost is as fellows:
Lime Feeder $ 1,800
Lime Mix Tanks (2) 3.7m3 ea. 10,200
Flash Mix Tank 8 m3 6,800
Instrumentation 5^000
Total $23,800
Caustic Neutralization System. A packaged treatment tank
and instrumentation system is employed. The unit consists
of an electronically equipped control panel, a reaction
chamber with high speed stirrer and storage tanks for
reagents. System costs based on Reference 8 are as follows:
142
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capacity Cost
2,500 gal/hr $11,000-13,000
6,250 gal/hr 21,000
12,500 gal/hr 25,000
Systems are selected for employment at plant operations
based on treatment flow requirements.
Solids Separators. Included in this category are separators,
centrifuges and disk filters employed by various plants in
the industries. The types of equipment considered and their
costs are listed below.
Super Separators (Reference 9)
150 - 225 gal/min $3,150
200 - 300 gal/min a,100
Industrial Separators (Reference 8)
200 - 400 gal/min $3,245
400 - 700 gal/min 3,630
Centrifuges (References 10 & 11)
15" x 17" $1,800
20" x 17" 2,200
12" x 30" 40,000
Disk Filter (Reference 12)
5 disks - 4" - 1 hp $17,000
The costs of vacuum pumps used in connection with disk
filters are as follows (Reference 4):
208 ft3/min 9.5 hp $5,000
310 fta/min 23 hp 7,400
Classifier (Reference 12)
D = 24" - 14«9", 2 hp $9,000
Installation. Many factors can impact on the cost of
installing equipment modules. These include wage rates,
whether the job is performed by outside contractors or
143
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regular employees and site dependent conditions, i.e.,
availability of sufficient electrical services.
In this study, installation cost is computed as 90% of the
cost of equipment which is installed. This factor is
derived from a brief analysis of data contained in Reference
13. The equipment cost used is the total equipment cost
less the cost of such items such as spare pumps and slag
bins; i.e., items which do not require installation.
Transportation. This cost is sensitive to the type of
equipment, its weight and volume and the transport distance.
A review of the transportation costs listed for pertinent
equipment items in Reference 4 and assuming transportation
distances of 200-^500 miles, 1 percent of the equipment cost
appears to be a reasonable estimate for this activity. This
factor is applied in the study.
Contingency and Fee. This cost is computed as 15% of the
sum of the costs for facilities, equipment, installation and
transportation.
Engineering. This cost is estimated as 30% of equipment
cost. One exception is a process which requires payment of
a license fee. The latter includes provision of detailed
engineering drawings. In this instance, the license fee is
used as the engineering cost.
LAND
The locations of secondary copper refineries range from
highly industrial to semi-rural sites. The cost of land is
estimated as $15,000 per hectare ($6000/acre).
ANNUAL COSTS
Amortization. Annual depreciation and capital costs are
computed as follows:
CA = B(r) x (1+r)to the nth power
(1+r)to the n-1 power
where CA = Annual cost
B = Initial Amount Invested
r = Annual Interest Rate
n = Useful Life in Years
144
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The computed cost is often referred to as the capital
recovery factor. It essentially represents the sum of the
interest cost and depreciation.
An interest rate of 10 percent is used. The expected useful
life of facilities is 20 years. The costs of equipment,
installation, transportation and engineering are amortized
over a 10 year period. No residual or salvage value is
assumed.
Operation and Maintenance. Costs include facility and
equipment repair and maintenance and operating labor.
Facility repair and maintenance are included as 3 percent of
facility costs; equipment repair and maintenance as 5
percent of the combined equipment and installation costs.
Personnel costs are based on an hourly rate of $12.00. This
includes fringe benefits, overhead and supervision
(Reference 3). Personnel are assigned for specific
activities as required.
Sludge and slag Disposal. Disposal costs can vary widely.
Chief cost determinants include the amount and type of
waste, on-site vs. contractor disposal, size of the disposal
operation and transport distances. The following disposal
costs have been used.
Dried Sludge/Slag
Contractor Disposal
$4.55/ton
Liquid Sludge
Contractor Disposal
$0.19/gal
Dried Sludge/Slag
On-Site Disposal
$1.82/ton
Dried Sludge/Slag
On-Site w/Ground Sealing
$2.27/ton
145
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Energy. Energy costs are based on the cost per horse-
power-year, computed as follows:
CI = 1.1 x HP x 0.7457 x Hr x Ckw
E x P
where
CY = Cost
HP = Total Horsepower Rating of Motors
E = Efficiency Factor
P = Power Factor
Hr = Annual Operating Hours
Ckw = Cost Per Kilowatt-Hour cf Electricity
A 10 percent allowance is included to account for
miscellaneous energy usage. Efficiency and power factors
are each assumed to be 0.9; the cost per kilowatt-hour,
$0.03.
Materials. The material costs shown below are used in this
study:
Sulfuric Acid
$0.054/lb
(Reference 14)
Flocculant
$0.91/lb
(Reference 15)
Hydrated Lime
$70.00/ton
(Reference 14)
Caustic Soda
$380/ton
(Reference 14)
Taxes and Insurance. The combined costs are included as 1
percent of the total investment cost.
Costs of Control and Treatment Alternatives
The following discussions present the capital and annual
costs for alternative control and treatment processes for
the various process wastewater streams which may be
introduced to POTW from secondary copper smelters and
refiners. Costs of alternatives are given for
146
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representative model plants. Where a discussion of a
process or a wastewater stream applies only to a single
plant, costs are developed for a model plant comparable in
size and process parameters.
Metal Cooling Water
Ingot Cooling (No Charcoal Cover). Costs for one control
alternative are developed in Tables 35 through 40 for three
model plant operations - one large, one medium, and one
small. The control process considered entails complete
recycling of all contact ingot cooling water. In the large
plant, this control alternative requires settling and
cooling of the waste water prior to recycling due to the
large volumes of water involved. In the medium and small
operations, the waste water is periodically pumped from the
quench pits to holding tanks while sludge is removed from
the pits. The water is then returned to the quench pits
without discharge of a bleed stream.
Costs for one treatment alternative were also developed for
these three plants. This data is presented in Tables 41
through 46. The treatment process considered consists of
simply settling process waste waters from this source. pH
adjustment is not assumed to te necessary due to the
typically high pH and low dissolved metals loading of this
stream. In the treatment process, the waste water from the
quench pits flows through two settling pits, each sized to
hold the volume of waste water generated in one day. The
waste water is discharged to a sewer from the settling pits.
Gravity flow is assumed.
Ingot Cooling (Charcoal Cover). The control and treatment
processes are essentially the same as those provided for
Ingot Cooling (no charcoal cover) as described above. The
major difference is that the use of charcoal increases the
amount of sludge generated in the cooling process. Several
waste water control options are considered. For the large
and the medium sized model plants, waste water control
includes settling, cooling, and filtration before recycle.
Additionally, a medium and a small plant operation are
considered in which the waste water is periodically pumped
to a holding tank while sludge is removed from the quench
pits, and then recycled. In the treatment process, the
waste water is directed through two settling pits before
being discharged. Control process costs are shown in Tables
47 to 54; treatment process costs are presented in Tables 55
to 60.
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Shot Quenching. Shot quenching control and treatment costs
are presented in Tables 61 to 64. The control and treatment
costs associated with phosphor shot quenching operations
(which will always require pH adjustment) are presented in
Tables 65 through 68. The waste water flow associated with
this operation is very small. In most cases, it would
appear that this small flow could be combined, treated or
controlled with other waste water streams in plants which
engage in this operation. Plant 14, however, uses once-
through cooling wate for this operation, resulting in a flow
rate of up to 760,000 gpd. Appropriately adjusted control
and treatment costs for this plant are presented in Tables
69 through 72. Based on the experience of other plants,
however, it appears that the rate of water use at this plant
could be drastically reduced by increasing reuse of the
water prior to discharge, thus significantly reducing
treatment and control costs. In addition, appropriately
adjusted treatment costs have been developed for phosphor
copper shotting operations at Plant 19, where neutralization
facilities are already in place. This data is presented in
Tables 73 and 74.
Billet Cooling. Only Plant 5 performs this operation, and
so only one model plant operation (appropriately sized) is
considered. The control and treatment alternatives
considered for this model plant operation are essentially
similar. The control alternative costs, which are presented
in Tables 74 and 75, are based upon settling of the effluent
prior to complete recycle. The costs of the treatment
alternative, which are shown in Tables 77 and 78, are based
upon settling of the effluent prior to introduction to a
sewer. Cost differences between these two alternatives
arise because of the additional pumping and piping required
for the recycle alternative. Neutralization is not assumed
to be necessary due to the typically high pH and low
dissolved metals loading of this stream.
Anode Cooling. One large model plant operation is
considered. The waste water control alternative considered
consists of settling, cooling and complete recycle. The
waste water treatment alternative involves settling followed
by introduction to a sewer. The settling pit is sized to
hold a one day supply of waste water. Gravity flow is
assumed, and no pH adjustment is assumed since the pH of
contact metal cooling water is typically high, and the
dissolved metals content is low. Control costs are shown in
Tables 79 and 80, and treatment costs are presented in
Tables 81 and 82.
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Furnace Exhaust Scrubbing Waste Water. Control and
treatment alternatives are considered for three model plants
- one large, one medium, and one small. The waste water
control alternative for the large model plant consists of
neutralization, settling, cooling, complete recycling, and
sludge dewatering. The control alternatives for the medium
and small sized model plants are similar except that the
need for waste water cooling is eliminated, due to the
smaller volumes of water involved. Hydrated lime is the
reagent used for neutralization of the waste water. Lime is
added at a rate of 0.32 kg/m* (2.7 lb/1,000 gallons) in the
large and medium sized model plants. The scrubber water of
the small model plant is assumed to contain phosphoric acid,
thus requiring additional lime. Reagent addition in this
plant is at the rate of 4 kg/m^ (33.3 lb/1,000 gallons).
Control costs for these three model plants are shown in
Tables 83 through 88.
Waste water treatment alternatives for the three model
plants are essentially similar to the waste water control
alternatives. The cooling equipment is eliminated in the
large model plant and pump and piping requirements are
reduced in all plants. Treatment costs are shown in Tables
89 to 94. It should be noted that the control and treatment
costs of the small model plant could be substantially
reduced by combining the waste water generated with other
waste streams of the plants for treatment and subsequent
recycle or discharge.
Slag Granulation Waste Water. Only one model plant is
considered since only one plant, Plant 11, performs this
operation, and so only one model plant, appropriately sized
and designed, was considered. The control alternative
considered consists of pH and adjustment, settling, cooling
and recycling of the waste water. The treatment alternative
entails settling only. Slag disposal costs are not assumed
chargeable to either of the processes. Control and
treatment costs for the selected model plant are shown in
Tables 95 to 98.
Electrolyte Waste Water. Only one plant performs this
operation, and so only one model plant, appropriately sized,
was considered. The control and treatment alternatives
evaluated are essentially similar, consisting of waste water
neutralization, settling, filtration, and sludge dewatering.
In the control process, the waste water is then recycled or
reused; in the treatment process it is pH-adjusted and
settled prior to introduction to a POTW. The reagent of
choice for neutralization is hydrated lime which is added to
the waste stream at the rate cf 6.8 kg/in* (56.6 lb/1,000
149
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gallons). The large amount of sludge generated by the heavy
lime addition requires sludge dewatering prior to disposal.
The addition of iron powder to the spent electrolyte to
remove copper by cementation is considered to be part of the
secondary copper production process, and the costs
associated with this operation were therefore not included
in this evaluation. The control alternative costs are
presented in Tables 99 to 102, and the treatment alternative
costs are presented in Tables 103 to 106.
Cost-Effectiveness
Table 107 gives cost-effectiveness relationships for treat-
ment and control alternatives for the major process
wastwaters from the secondary copper smelting and refining
industry. Costs are derived from the cost models presented
previously in this section. Since costs per metric ton of
metal product will differ for varying plant sizes, costs are
given for small, medium and large plants. Where a
particular treatment or control model is not practical or
meaningful for a plant (e.g., storing of metal cooling water
prior to recycle in a large plant is impractical), no such
model costs are given.
The process wastewaters considered are metal cooling water,
furnace exhaust scrubber water, electclyte wastewater and
slag granulation wastewater. Costs are given for ingots
both with and without charcoal cover.
Metal Cooling Water, it will be noticed that costs for
treating metal cooling wastewater are higher when charcoal
is used than when it is not used. The increased costs are
attributable to the greater quantity of sludge which must be
disposed where charcoal cover is used. It will also be
noticed that the need for cooling the quench water before
recycle adds considerable expense.
Three types of technologies are considered with varying
degrees of effectiveness. Coarse settling of solids occurs
by virtue of the fact that quenching takes place in pits,
and so the effectiveness of the coarse settling that
inevitably occurs as part of the process can be represented
by the average raw wastewater data presented previously in
Tables 13 through 15. A second alternative is the addition
of another settling pit to ensure adequate retention time
for effective solids settling. Since no secondary copper
plants discharging to POTW currently have such systems, no
effectiveness data is presented. A third alternative is
complete recycle and reuse of process waters from this
source, resulting in no discharge of process waste waters.
150
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Furnace Exhaust Scrubwater. Effectiveness data for settling
presented in Table 107 are the averaged data from settled
emissions scrubwater sampled at Plants 5 and V, which have
been presented previously in Tables 28 and 30, respectively.
The effectiveness data for lime or caustic treatment plus
settling are for Plant R previously presented in Table 34.
There are no cost models for simple settling of emissions
scrubwater since the effectiveness data clearly indicate
high levels of metals after settling treatment only. Costs
of emission scrubber water treatment for medium and small
plants are relatively high per metric ton of metal produced.
In addition to lime treatment and settling, cooling of
scrubwater in cooling towers would te necessary for recycle,
thus adding to the cost.
Electrolytic Refining Wastewater. Electrolyte wastewater is
produced at only one large plant discharging to a POTW. At
present, electrolyte wastewater is discharged from the one
plant to a POTW without further treatment after iron
cementation to recover copper values. This wastewater is*
similar to that treated by Plant R. The effectiveness data
for Plant R previously given in Table 33 has therefore been
used as a measure of the cost-effectiveness of pH adjustment
and settle treatment of electrolyte wastewater.
Slag Granulation Water. Slag granulation water undergoes
coarse settling in granulation pits, where most of the
solids settle out. Effectiveness for removal of metals is
presented in Table 107 and is derived from data on Plant E,
a direct discharger. Since the pits are part of the
process, the costs of the pits are not attributable to
pollution control. The cost model for this operation
developed previously in this section reflects additional
settling of overflow from the quench pits so as to ensure
adequate retention for effective settling. Since additional
settling is not practiced by the industry before discharge
to a POTW, no effectiveness data for additional settling is
presented. A cooling tower adds additional cost if there is
to be complete recycle of slag granulation water.
Economics of Additional Control Practices
Table 108 summarizes the additional treatments and controls
which are estimated to be needed by each of the secondary
copper smelters discharging to POTW in order to either meet
the recommended pretreatment control levels or to achieve
zero discharge. The numbers in parentheses are the
appropriate cost model tables for satisfying the estimated
needs for treatment and control.
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The estimated capital and annual costs to individual plants
to pretreat or recycle process wastewaters are shown in
Table 109. The total annual and capital costs for all
seveneteen plants currently discharging process wastewaters
to POTW are also presented.
This table shows that in general, the capital and annual
costs of the recycling alternative are 35 to 20 percent
higher than the capital and annual costs of the
corresponding pretreatment alternative. These higher costs
are generally due to the following considerations:
1. Additional pumps and piping are required for the
recycle alternative, since gravity flow is assumed in
the pretreatment alternative.
2. Additional water storage is required for the
recycle alternative.
3. Cooling towers are necessary in certain instances
in the recycle alternative.
It should be noted, however, that sewer charges, the cost of
water, and the costs associated with compliance monitoring
are not included in the cost calculations for the treatment
alternative. These costs will tend to partially offset the
higher apparent cost of the recycle alternative, and it is
expected that complete recycle of process wastewater will be
an economically attractive alternative in most cases.
The "costs/metric ton" shown are based on estimated plant
capacities as shown in the model plant descriptions
presented elsewhere in Section VIII of this report.
Diversions from this procedure were necessary where more
than one treatment process was required in a plant
operation. The plant capacities noted in the footnotes of
Table 109 were employed in these instances, and it should be
noted that the actual costs per ton of production may vary
significantly from the indicated costs per ton of capacity,
depending on the percent of capacity utilized at any given
time.
152
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Nonwater Quality Aspects
Energy Requirements
Specific data on energy requirements were not available from
any of the plants studied. Electrical energy is consumed in
the waste water treatment for operation of process
equipment, such as pumps, blowers, centrifuges, and filters.
The vast majority of operations was located outdoors in
unheated and unlighted areas, and little fuel and
electricity consumption was required. Mechanical operations
totaling 50 HP or less are typical; these energy
requirements would amount only to 14.9 kwhr/annual kkg (13.5
kwhr/annual ton) (for 7200 hr/yr, and 18,000 kkg annual
secondary copper production) or $0.45/kkg ($0.42/ton) (at
$0.03/kwhr), which is negligible when compared with the
total energy consumption in the industry.
Thermal energy requirements are nearly nonexistent in all
waste water treatment processes, except for the dry
processing of the metal-rich slag. This alternative
involves remelting the metal-rich slag and low-grade scrap
metal in a blast furnace, cupola, or rotary furnace. The
thermal requirement for fuel for the slag treatment is
estimated at 150,510 kg-cal/kkg (542,670 Btu/ton) (10,000
tons/year of slag processed) or $5.25/kkg ($4.77/ton) (at
$0.03/kwhr) .
Solid Waste Production
All of the control and treatment technologies identified in
this document produce solid waste as an adjunct to their
operation. Solid wastes are produced in pH-adjustment
operations employed for the purpose of neutralization
(resulting in precipitation of insoluble salts) or to
increase the insolubility of metal hydroxides. Settling of
solids, including suspended metals, is necessary for each
waste stream in most cases. Solid waste generation
increases dramatically when charcoal covers are used in
ingot cooling operations. In most cases, however, settling
of coarse solids, particularly in charcoal-covered ingot
manufacturing operations, is presently the practice of the
industry by virtue of the fact that metal cooling and slag
granulation and shot manufacturing operations take place in
pits. Solid wastes will also te generated by the
alternative pretreatment technologies in the form of
insoluble hydroxides.
The treatment process at one direct discharger (Plant R)
involves extensive use of pH adjustment, settling, and
153
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filtration for the treatment of effluents from copper
smelting operations. A sludge production of 98 kg/kkg (196
Ib/ton), containing 35 percent solids by weight, was
reported.
All other solid wastes noted result from the collection of
solids involved in the production process (e.g., charcoal
employed for prevention of metal oxidation) or are combined
with production solid wastes (e.g., a small quantity of
neutralization sludge at another direct discharger, Plant G,
is discharged with the depleted slag after the milling and
classifying operation). Plant 11 charges the solid wastes,
including charcoal, collected from the ingot quench
operation to a cupola furnace to recover copper values.
154
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TABLE 35. MODEL-PLANT CONTROL COSTS FOR
IMDUSTRY: Secondary Copper
portress- Metal Cooling (no charcoal
PLANT ANNUAL CAPACITY IN METRIC (SHORT)
PLANT VVASTFVU ATE R FLOW: 955 1/min,
TREATMENT ALTERNATIVE: Settle, COOl
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT
cover)
Large
TOM*. 22,730 MT (25,000 ST) Plant
7 hrs/day, 250 days/yr
, recycle
$17,200
19,300
15,600
200
7.800
5,800
$65,900
$ 3,000
$ 8,680
11,260
880
2,760
660
$24,240
<«i $1.07 CO. 971
155
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TABLE 36. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (no charcoal cover)
MODEL PLANT ANNUAL CAPACITY: 22,730 MT (25,000 ST)
TREATMENT ALTERNATIVE: Settle, cool, recycle
Facilities:
Settling pits (2) 6 m3 ea. 3 x 2 x 1 m $2,600
Holding pits 35 m3 2 x 3.5 x 7 m 9,400
27 nT 2 x 3.5 x 3.8 m 5,200
Equipment:
Cooling tower 955 1/min 7 HP 4,900
Pumps 3+1 water pumps 1200 1/min $2000 - 15 HP ea. 8,000
Piping 200 m of 15 cm pipe at $32/m 6,400
Labor:
15 hrs/week, 50 weeks/yr at $12/h 9,000
Sludge Disposal:
175 MT/yr 880
Energy:
52 HP, 7 hrs/day, 250 day/yr 2,760
Land:
0.2 ha at $15,000/ha 3,000
156
-------
TABLE 37. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (no charcoal cover)
Medium
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 9,820 MT (10,800 ST) plant
PLANT WASTEWATER FLOW: 34 m once every three weeks
TREATMENT ALTERNATIVE: Store, recycle
INVESTMENT ($)
FACILITIES
EQUIPMENT $ 9,700
8,700
INSTALLATION
TRANSPORTATION !££_
CONTINGENCY AND FEE 2,800
ENGINEERING 2,900
TOTAL INVESTMENT $24,200
LAND ($)
TOTAL ANNUAL COSTS
157
ANNUAL COSTS ($)
AMORTIZATION $ 5>490
OPERATION AND MAINTENANCE 5,920
SLUDGE/SLAG DISPOSAL 38°
ENERGY 19-
MATERIALS
TAXES AND INSURANCE 24°
$ 8,040
COST PER METRIC (SHORT) TON OF PRODUCT <$) $0.82 (0.74)
-------
TABLE 38. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (no charcoal cover)
MODEL PLANT ANNUAL CAPACITY: 9,820 MT (10,800 ST)
TREATMENT ALTERNATIVE: Store, recycle
Equipment:
Holding tank 34 m $7,200
Pump
1 ea. (150 1/min) water pumps $1300 - 2 HP 1,300
Piping
50 m of 10 cm pipe at $24/m 1,200
Labor:
5 hrs/week, 50 weeks/yr at $12/hr 3,000
Sludge Disposal:
75 MT/yr 380
Energy:
2 HP, 70 hrs/yr 10
Land: negligible
158
-------
TABLE 39.
MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROC ESS: Metal Cooling (no charcoal cover)
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TOMS: 3>275
PLANT WASTEWATER F. nw
TREATMENT ALTERNATIVE:
SH
(5,600 ST) plant
H.4 m every 3 weeks
Store, recycle
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
$ 5'600
5,000
1'600
1>70°
$14,000
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
2020
2,530
4>650
COST PER METRIC (SHORT) TON OF PRODUCT ($)
$1.42 (1.29)
159
-------
TABLE 40. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (no charcoal cover)
MODEL PLANT ANNUAL CAPACITY: 5,275 MT (5,600 ST)
TREATMENT ALTERNATIVE: Store, recycle
Equipment:
Holding tank 12 m3 $3,900
Pump (100 1/min) $1,250 - 2 HP 1,300
Piping 25 m of 5 cm pipe at $18/m 400
Labor:
3 hrs/week; 50 weeks/yr at $12/hr 1,800
Sludge Disposal:
30 MT/yr 150
Energy:
2 HP - 40 hrs/yr 10
Land: negligible
160
-------
TABLE 41. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (no charcoal cover) _ _ _ _
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TOMS: 22,730 MT (25,000 ST)
PLANT WASTEWATER FLOW: 955 I/"*"? 7 hrs/day. 250 days/yr
TREATMENT ALTERNATIVE: Settle, discharge to POTW
INVESTMENT ($)
FACILITIES $40'200
EQUIPMENT _
TRANSPORTATION
INSTALLATION _ 4>30°
CONTINGENCY AND FEE 7>40°
ENGINEERING lj400
TOTAL INVESTMENT $58,100
LAND ($) $ 3>000
ANNUAL COSTS ($)
$ 6,410
AMORTIZATION —
Q
OPERATION AND MAINTENANCE '
SLUDGE/SLAG DISPOSAL
ENERGY HI-
MATERIALS """
580
TAXES AND INSURANCE
TOTAL ANNUAL COSTS $16>75°
COST PER METRIC (SHORT) TON OF PRODUCT ($) $0.74 (0.67)
161
-------
TABLE 42. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (no charcoal cover)
MODEL PLANT ANNUAL CAPACITY: 22,730 MT (25,000 SI)
TREATMENT ALTERNATIVE: Settle, discharge to POTW
Facilities:
Settling pits (2) 420 m3 14 x 10 x 3 m $40,200
Equipment:
Piping 150 m of 15 cm pipe at $32/m 4,800
Labor:
12 hrs/week, 50 weeks/yr at $12/hr 7,200
Sludge Disposal:
175 MT/yr 880
Land:
.2 ha at $15,000/ha 3,000
162
-------
TABLE 43.
MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS- Metal Cooling (no charcoal cover)
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 9 .820 MT
PLAIMTWASTEWATER FLOW: 34 m /day, 250 days/yr
TREATMENT ALTERNATIVE: Settle, discharge to POTW
(10,800 ST) fiS?»
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT ($)
$ 8,800
1,200
1,100
1,700
400
$13,200
$ 1,470
3,380
380
130
$ 5,360
$0.55 (0.50)
163
-------
TABLE 44. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (no charcoal cover)
MODEL PLANT ANNUAL CAPACITY: 9,820 MT (10,800 ST)
TREATMENT ALTERNATIVE: Settle, discharge to POTW
Facilities:
Settling pits (2) 35 m3 4.2 x 4.2 x 2
Equipment:
Piping 50 m of 10 cm pipe at $24/m
Labor:
5 hrs/week, 50 weeks/yr at $12/hr
Sludge Disposal:
75 MT/yr
Land:
$8,800
1,200
3,000
380
negligible
164
-------
TABLE 45. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (no charcoal cover)
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 3'275 m (3>600 ST) Plant
PLANT WASTEWATER FLOW: U-4 m /day> 25° days/yr _
TREATMENT ALTERNATIVE; Settle, discharge to POTW
INVESTMENT ($)
FACILITIES $5,000
EQUIPMENT 900
INSTALLATION 800
TRANSPORTATION —
CONTINGENCY AND FEE 1,000
ENGINEERING 300
TOTAL INVESTMENT $8,000
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION $900
OPERATION AND MAINTENANCE 2,040
SLUDGE/SLAG DISPOSAL 150
ENERGY ---
MATERIALS
TAXES AND INSURANCE 80
TOTAL ANNUAL COSTS ^'170
COST PER METRIC (SHORT) TON OF PRODUCT ($) $0.97 (0.88)
165
-------
TABLE .46. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (no charcoal cover)
MODEL PLANT ANNUAL CAPACITY: 5,275 MT (3,600 ST)
TREATMENT ALTERNATIVE: Settle, discharge to POTW
Facilities:
Settling pits (2) 12 m 3 x 2 x 2 m $5,000
Equipment:
Piping 50 m of 5 cm pipe at $18/m 900
Labor:
3 hrs/week, 50 weeks/yr at $12/hr 1,800
Sludge Disposal:
30 MT/yr 150
Land: negligible
166
-------
TABLE 47. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS- Metal Cooling (charcoal cover)
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS; 22>73° **** (25»°0° ST) piafit
PLANT WASTEWATER FLOW: 955 1/min, 7 hrs/day, 250 days/yr
TREATMENT ALTERNATIVE: Settle, cool, filter, recycle
INVESTMENT ($)
FACILITIES $17,200
EQUIPMENT 24,500
INSTALLATION 20,300
TRANSPORTATION 200
CONTINGENCY AND FEE 9,500
ENGINEERING 7,400
TOTAL INVESTMENT $69.600
LAND ($) $ 5.000
ANNUAL COSTS ($)
AMORTIZATION $10,550
OPERATION AND MAINTENANCE 24»360
SLUHGE/SLAG DISPOSAL !»680
ENERGY 2,760
MATERIALS ""
TAXES AND INSURANCE
TOTAL ANNUAL COSTS $40,050
COST PER METRIC (SHORT) TON OF PRODUCT ($) $1.76 (1.60)
167
-------
TABLE 48. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (charcoal cover)
MODEL PLANT ANNUAL CAPACITY: 22,730 MT (25,000 ST)
TREATMENT ALTERNATIVE: Settle, cool, filter, recycle
Facilities:
Settling pits (2) 6 m ea. 3 x 2 x 1 m $ 2,600
Holding pits 35 m_ 2x3.5x7m 9,400
27 m 2 x 3.5 x 3.8 m 5,200
Equipment:
Cooling tower 955 1/min 7 HP 4,900
Pumps 3+1 water pumps 1,200 1/min $2,000 - 15 HP ea 8,000
Piping 200 m of lb cm pipe at $32/m 6,400
Solids separator 4,100
Holding tank 1.3 m 1,100
Labor:
36 hrs/week, 50 weeks/yr at $12/hr 21,600
Sludge Disposal:
335 MT/yr 1,680
Energy:
52 HP, 7 hrs/day, 250 days/yr 2,760
Land:
0-2 ha at $15,000/ha 3,000
168
-------
TABLE 49. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (charcoal cover)
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 8>
PLANT WASTEWATER FLOW: 570 1/min, 7 hrs/day,
TREATMENT ALTERNATIVE: Settle, cool, filter.
725 MT (9,600 ST) ^T
250 days/yr
recycle
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT ($)
$11,500
17,700
14,300
200
6,500
5,300
$55,500
$ 3,000
$ 7,460
16,340
1,000
1,700
_-_
560
$27,060
$3.27 (3.00)
169
-------
TABLE 50. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (charcoal cover)
MODEL PLANT ANNUAL CAPACITY: 8,725 MT (9,600 ST)
TREATMENT ALTERNATIVE: Settle, cool, filter, recycle
Facilities:
Settling pits (2) 3 m ea. 3 x 1 x 1 m $ 2,000
Holding pit 17.6 m^ 1.2 x 2.4 x 6,1 m 5,300
13.8 nr 1.2 x 2.4 x 4.8 m 4,200
Equipment:
Holding tank .8 m 900
Cooling tower 570 1/min 5 HP 4,200
Solids separator 570-850 1/min (laval) 3,200
Pumps 3+1 water pumps 800 1/min $1,750/9 HP ea. 7,000
Piping 100 m of 10 cm pipe at $24/m 2,400
Labor:
24 hrs/week; 50 weeks/yr at $12/hr 14,400
Sludge Disposal:
200 MT/yr 1,000
Energy:
32 HP, 7 hrs/day, 250 days/yr 1,700
Land:
.2 ha at $15,000/ha 3,000
170
-------
TABLE 51. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (charcoal cover)
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 9 »820 M
T (10,800 ST) pfantm
PLANT WASTEWATER FLOW: 34 m OHCe/Week
TREATMENT ALTERNATIVE: Store, recycle
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT ($)
$ 9,700
8,700
100
2,800
2,900
$24,200
—
$ 3,490
10,520
1,130
20
240
$15,400
$1.57 (1.43)
171
-------
TABLE 52. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (charcoal cover)
MODEL PLANT ANNUAL CAPACITY: 9,820 MT (10,800 ST)
TREATMENT ALTERNATIVE: Store, recycle
Equipment:
Storage tank 34 m3 $7,200
Pump (150 1/min) $1,300 - 2 HP 1,300
Piping 50 m of 10 cm pipe at $24/m 1,200
Labor:
16 hrs/week; 50 weeks/yr at $12/hr 9,600
Sludge Disposal:
225 MT/yr 1,130
Energy:
2 HP, 1 hr/day, 250 days/week 20
Land: negligible
172
-------
TABLE 53. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (charcoal cover)
small
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TOMS: 5,275 MT (5,600 ST) Plant
PLANT WASTEWATER FLOW: 10.6 m once/week
TREATMENT ALTERNATIVE: Store, recycle
INVESTMENT ($)
FACILITIES
EQUIPMENT $ 5>5°°
INSTALLATION 4,800
TRANSPORTATION 10°
CONTINGENCY AND FEE I
ENGINEERING 1,600
TOTAL INVESTMENT $15,500
LAND ($) I"
ANNUAL COSTS ($)
AMORTIZATION , $ 1*920.
OPERATION AND MAINTENANCE _ J
SLUDGE/SLAG DISPOSAL , 450
ENERGY _ IP-
MATERIALS _ —
TAXES AND INSURANCE
TOTAL ANNUAL COSTS $ 7,810^
COST PER METRIC (SHORT) TON OF PRODUCT ($) $2.58 (2.16)
173
-------
TABLE 54. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (charcoal cover)
MODEL PLANT ANNUAL CAPACITY: 3,275 MT (5,600 ST)
TREATMENT ALTERNATIVE: Store, recycle
Equipment:
7
Storage tank 11 m $3,600
Pump (100 1/min) $1250 - 2 HP 1,300
Piping 25 m of 5 cm pipe at $18/m 400
Labor:
8 hrs/week; 50 weeks/yr at $12/hr 4,800
Sludge Disposal:
90 MT/yr 450
Energy:
2 HP, 2 hrs/week, 50 weeks/yr 10
Land: negligible
174
-------
TABLE 55. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS- Metal Cooling (charcoal cover)
27 7^0
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: *" ' ' °
PLANT WASTEWATER FLOW: 955 1/min' 7 hrs/day, 250
MT (25,000 ST) £f|g£
days/yr
TREATMENT ALTERNATIVE: Settle, discharge to POTW
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUOGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT <$)
$40,200
4,800
4,300
7,400
1,400
$58,100
$ 3,000
$ 6,410
16,060
1,680
580
$24,730
$1.09 (0.99)
175
-------
TABLE 56. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (charcoal cover)
MODEL PLANT ANNUAL CAPACITY: 22,730 NTT (25,000 ST)
TREATMENT ALTERNATIVE: Settle, discharge to POTW
Facilities:
Settling pits (2) 420 m3 14 x 10 x 3 m $40,200
Equipment:
Piping 150 m of 15 cm pipe at $32/m 4,800
Labor:
24 hrs/week, 50 weeks/yr at $12/hr 14,400
Sludge Disposal:
335 MT/yr 1,680
Land:
0.2 ha at $15,000/ha 3,000
176
-------
TABLE 57. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (charcoal cover)
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 9,820 MT (10,800 ST) Plant
PLANT WASTEWATER FLOW: 34 m /day, 250 days/yr
TREATMENT ALTERNATIVE: Settle, discharge to POTW
INVESTMENT ($)
FACILITIES $ 8 '80Q
EQUIPMENT 1,200
INSTALLATION 1,100
TRANSPORTATION —.
CONTINGENCY AND FEE 1,700
ENGINEERING 400
TOTAL INVESTMENT $15,200
LAND ($) ---
ANNUAL COSTS ($)
AMORTIZATION f 1,470
OPERATION AND MAINTENANCE 7,580
SLUDGE/SLAG DISPOSAL 1,130
ENERGY """
MATERIALS """
TAXES AND INSURANCE 15°
TOTAL ANNUAL COSTS $10,310
COST PER METRIC (SHORT) TON OF PRODUCT ($)
$1.05 (0.95)
-------
TABLE 58.
COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (charcoal cover)
MODEL PLANT ANNUAL CAPACITY: 9,820 MT (10,800 ST)
TREATMENT ALTERNATIVE: Settle, discharge to POTW
Facilities:
Settling pits (2) 35 m3 4.2 x 4.2 x 2 m
Equipment:
Piping 50 m of 10 cm pipe at $24/m
Labor:
12 hrs/week; 50 weeks/yr at $12/hr
Sludge Disposal:
225 MT/yr
Land:
$8,800
1,200
7,200
1,130
negligible
178
-------
TABLE 59. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS- Metal Cooling (charcoal cover)
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 3»275 W
PLANT WASTEWATER FLOW: 10. 6m /day
' (3,600 ST) pf{£l
TREATMENT ALTERNATIVE: Settle, discharge to POTW
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT <$)
$5,000
900
800
--
1,000
300
$8,000
__
$ 900
5,040
450
--
--
80
$6,470
$1.98 (1.80)
179
-------
TABLE 60.
COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Metal Cooling (charcoal cover)
MODEL PLANT ANNUAL CAPACITY: 3,275 MT (5,600 ST)
TREATMENT ALTERNATIVE: Settle, discharge to POTW
Facilities:
Settling pits (2) 12 m 3 x 2 x 2 m
Equipment:
Piping 50 m of 5 cm pipe at $18/m
Labor:
6 hrs/wk, 50 weeks/yr at $12/hr
Sludge Disposal:
90 MT/yr
Land:
$5,000
900
4,800
450
negligible
180
-------
TABLE 61. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Shot quenching
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 38° ^ ^42° ST)
PLANT WASTEWATER FLOW: 5-8 m /mo
TREATMENT ALTERNATIVE: Store» recycle
INVESTMENT ($)
FACILITIES
EQUIPMENT $4,100
INSTALLATION 3,700
TRANSPORTATION
CONTINGENCY AND FEE 1,200
ENGINEERING 1,200
TOTAL INVESTMENT $10,200
LAND ($)
181
ANNUAL COSTS ($)
AMORTIZATION $1.470
OPERATION AND MAINTENANCE 530
SLUDGE/SLAG DISPOSAL --
ENERGY ]£_
MATERIALS
TAXES AND INSURANCE 100
TOTAL ANNUAL COSTS $2,110
COST PER METRIC (SHORT) TON OF PRODUCT ($) $5.55 (5.05)
-------
TABLE 62. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Shot Quenching
MODEL PLANT ANNUAL CAPACITY: 580 MT (420 ST)
TREATMENT ALTERNATIVE: Store, recycle
Equipment:
Storage tank 4 m3 • $2,000
Pump (100 1/min) 1,200
Piping 50 m of 5 cm - pipe @ $18/m 900
Labor:
1 hr/month; at $12/hr 140
Sludge Disposal: negligible
Energy: 10
Land: negligible
182
-------
TABLE 63. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Shot Quenching
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 38° m (42° ST)
PLANT WASTEWATER FLOW: ,3,8 m5 /Mo
TREATMENT ALTERNATIVE; Settle. discharge to POTW
INVESTMENT ($)
FACILITIES ai.nnn
EQUIPMENT 400
INSTALLATION 4f)f)_
TRANSPORTATION --
CONTINGENCY AND FEE 300
ENGINEERING 100
TOTAL INVESTMENT $2,200
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION . . $ 260
OPERATION AND MAINTENANCE 560
SLUDGE/SLAG DISPOSAL --
ENERGY ^_
MATERIALS '--
TAXES AND INSURANCE . 20
TOTAL ANNUAL COSTS $ 640
COST PER METRIC (SHORTJ TON OF PRODUCT <$) $1.68 (1.53)
183
-------
TABLE 64. COST COMPONENTS
INDUSTRY; Secondary Copper
PROCESS: Shot Quenching
MODEL PLANT ANNUAL CAPACITY: 580 MT (420 ST)
TREATMENT ALTERNATIVE: Settle, discharge to POTW
Facilities:
Settling pit 4m3 2x2xlm $1,000
Equipment:
Piping 25 m of 5 cm-pipe at $10/m 400
Labor:
2 hrs./mo at $12/hr. 290
Sludge Disposal: negligible
Land: negligible
184
-------
TABLE 65. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Phosphor Shot Quenching
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS:
380 MT (420 ST)
PLANT WASTEWATER FLOW: 3.8 m /mo
TREATMENT ALTERNATIVE: Neutralize, store,
recycle
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT ($)
*
*
7,300
6,600
100
2,100
2,200
$18,300
$ 2,640
1,280
10
20
180
$ 4,130
$10.87 f9.881
185
-------
TABLE 66. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Phosphor Shot Quenching
MODEL PLANT ANNUAL CAPACITY: 580 MT (420 ST)
TREATMENT ALTERNATIVE: Neutralize, store, recycle
Equipment:
Mixing/Settling Tank 4 m3 2 HP $ 5,200
Pump (100 1/min) 2 HP 1,200
Piping 50 m of 5 cm pipe at $18/m 900
Labor:
4 hrs/mo at $12/hr 580
Sludge Disposal: Negligible
Energy:
4 HP, 4 hrs/mo, 12 mo/yr 10
Materials:
Hydrated lime (4 Kg/m3), 0.2 MT/yr at $77/MT 20
Land: Negligible
186
-------
TABLE 67. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS- Phosphor Shot Quenching
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS:
PLANT WASTEWATER FLOW: 3.8 m /mo
TREATMENT ALTERNATIVE: Neutralize, settle,
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT ($)
380 MT (420 ST)
discharge to POTW
$ --
5,600
5,000
100
1,600
1,700
$14.000
$ 2,020
1,110
--
10
20
140
$ 3,300
$8.68 f$7.891
187
-------
TABLE 68. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Phosphor Shot Quenching
MODEL PLANT ANNUAL CAPACITY: 380 MT (420 ST)
TREATMENT ALTERNATIVE: Neutralize, settle, discharge to POTW
Equipment:
Mi
Piping 25 m of 5 cm pipe at $18/m 400
Mixing/settling Tank 4 m 2 HP $ 5,200
Labor:
4 hrs/mo at $12/hr 580
Energy:
2 HP, 4 hrs/mo, 12 mo/yr 10
Materials:
Hydrated lime (4 Kg/m3), 0.2 MT/yr at $77/MT 20
Land: Negligible
188
-------
TABLE 69. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS- Phosphor-copper emission scrubbing
and shot quenching-Plant 14
PLANT ANNUAL CAPACITY IN METRIC (W^T,™.. 820 NTT (900 ST) 1530 MT (1680 ST
PI ANT WIASTPWATFR FLOW. 130 m f\\T , 16 hrs/day
1 m3/hr, 16 hrs/day,
TRFATMENT ALTERNATIVE: Lime Treatment, Settle
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT ($)
, 120 days/yr
250 days/yr
, Recycle
$ 25,600
60,000
48,900
600
20,300
18,000
$173.400
$ 3,000
$ 23,780
13,530
5,030
6,010
9,170
1,730
$ 59,250
$25.21 ($22.921
189
-------
TABLE 70. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Phosphor-copper emission scrubbing and shot quenching— Plant 14
MODEL PLANT ANNUAL CAPACITY: 820 MT (900 ST)
1550 MT (1,680 ST)
TREATMENT ALTERNATIVE: Lime treatment, settle, recycle
Pacilities:
Settling pits (2) 190 m3 8x8x3m $25,600
Equipment:
Lime treatment system 12 HP 32,400
Pumps 2+1 water pump 3,000 1/min $3,200 30 HP ea. 9,600
1+1 slurry pump $2,500 1 HP 5,000
Piping
200 m of 30 cm pipe at $65/m 13,000
Labor:
4 hrs/day, 120 days/yr at $12/hr 5,760
1 hr/day, 130 days/yr at $12/hr 1,560
Sludge Disposal:
1060 MT/yr 5,030
Energy:
63 HP, 16 hrs/day, 120 days/yr 3,670
37 HP, 16 hrs/day, 130 days/yr 2,340
Materials:
3
0.3 Kg NaOH/m^, 104 MT/yr at $77/MT 8,010
Land:
4 Kg NaOH/m3>, 15 MT/yr at $77/MT I,'l60
0.2 ha at $15,000/ha 3,000
190
-------
TABLE 71. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS- Phosphor Copper Shot Quench Water -
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 82°
Plant 14
MT (900 ST)
PLANT WASTEWATER FLOW: 13° ra /hr> 16 hrs/day
TREATMENT ALTERNATIVE: Lime treatment, settle,
discharge to POTW
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT ($)
$ 25,600
50,300
40,100
500
17,500
15,100
$149,100
$ 3.000
$ 20,270
11,050
2,510
8,010
1,490
$ 43,330
$52.84 ($48.03)
191
-------
TABLE 72. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Phosphor Copper Shot Quench Water - Plant 14
MODEL PLANT ANNUAL CAPACITY: 820 MT (900 ST)
TREATMENT ALTERNATIVE: Lime treatment, settle, discharge to POTW
Facilities:
Settling pits (2) 190 m3 8x8x3m $ 25,600
Equipment:
Lime treatment system 12 HP 32,400
Pumps 1+1 water pump $3,200 ea. 30 HP ea. 6,400
1+1 slurry 2,500 1 HP ea. 5,000
Piping
100 m of 30 cm pipe at $65/m 6,500
Labor:
4 hrs/day, 120 days/yr at $12/hr 5,760
Energy:
43 HP, 16 hrs/day, 120 days/yr 2,510
Materials:
0.3 Kg NaOH/m3, 104 MT/yr at $77/MT 8,010
Land :
0.2 ha at $15,000/ha 3,000
192
-------
TABLE 73. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
. Phosphor Copper Shot Quenching - Plant 19
. ____ ___ -- .--..-._.- -- - -:_-_—_n—-
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 650 MT f715 ST")
PLANT WASTEWATER FLOW:_
TREATMENT ALTERNATIVE: Settling, discharge to POTW
INVESTMENT ($)
FACILITIES
EQUIPMENT 1,600
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
$ 4.600
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
$ 880
TOTAL ANNUAL COSTS _
COST PER METRIC (SHORT) TON OF PRODUCT ($) ,$1 .55 U.25)
193
-------
TABLE 74. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Phosphor Copper Shot Quenching - Plant 19
MODEL PLANT ANNUAL CAPACITY: 650 MT (715 ST)
TREATMENT ALTERNATIVE: Settling, discharge to POTW
Equipment:
Settling Tank 19 m3 $5,000
Piping
25 m of 10 cm pipe at $24/m 600
Note: Only 1/3 of costs charged to Secondary Copper operation.
The other 2/3 of costs are assigned to Secondary Aluminum
operation performed at the same facility.
194
-------
TABLE 75. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Billet Cooling
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 48
PLANT WASTEWATER FLOW: 189 1/min. , 8/hrs/day,
TREATMENT ALTERNATIVE: Store, recycle
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT ($)
,980 MT (53,900 ST)
5.5 days/wk
$3,600
2,700
2,400
.--
1,300
800
$10,800
--
$1 ,3sn
960
20
200
- ..
110
$2,670
$0.05 (0.04)
195
-------
TABLE 76. COST COMPONENTS
INDUSTRY: Secondary Copper^
PROCESS: Billet Cooling
MODEL PLANT ANNUAL CAPACITY: 48,980 MT (55,900 ST)
TREATMENT ALTERNATIVE: Store, recycle
Facilities:
Storage pit 90 m3 6 x 5 x 3 m $3,600
Equipment:
Pump 200 1/min. $1500 - 3 Hp 1,500
Piping 50 m of 10 cm pipe at $24/m 1,200
Labor:
1 hr/week, 50 weeks/yr at $12/hr 600
Sludge Disposal: 4 MT/yr 20
Energy:
3 Hp, 8 hrs/day, 5.5 days/wk, 50 wks/yr 200
Land: negligible
196
-------
TABLE 77. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Billet Cooling
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 48>980 m (55,900 ST)
PLANT WASTEWATER FLOW:
189 1/min, 8/hrs/day, 5.5 days/wk
TREATMENT ALTERNATIVE: Settle> discharge to POTW
INVESTMENT ($)
FACILITIES $5,600
EQUIPMENT 600
INSTALLATION 500
TRANSPORTATION --
CONTINGENCY AND FEE 700
ENGINEERING 200
TOTAL INVESTMENT $5,600
LAND ($)
ANNUAL COSTS <$)
AMORTIZATION $ 630
OPERATION AND MAINTENANCE 760
SLUDGE/SLAG DISPOSAL 20
ENERGY —
MATERIALS
TAXES AND INSURANCE 60
TOTAL ANNUAL COSTS $1,470
COST PER METRIC (SHORT) TON OF PRODUCT ($) $0.03 f 0.031
197
-------
TABLE 78.
COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Billet Cooling
MODEL PLANT ANNUAL CAPACITY: 48,980 MT [53,900 ST)
TREATMENT ALTERNATIVE: Settle, discharge to POTW
Facilities:
Settling pit 90 m3 6x5x3
Equipment:
Piping 25 m of 10 cm pipe at $24/m
Labor:
1 hr/wk, 50 weeks/yr at $12/hr
Sludge Disposal:
4 MT/yr
Land:
$3,600
600
600
20
negligible
198
-------
TABLE 79.
MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Anode Cooling
PLANT ANNUAL CAPACITY IN METRIC (SHORT! TONS: 81>
PLANT WASTEW ATE R FLOW: 3>030 1/min, 6 hrs/day,
660 MT (89,800 ST)
5.5 days/wk
TREATMENT ALTERNATIVE: Settle, cool, recycle
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT ($)
$30.400
29,600
23,600
300
12,600
8,900
$105,400
$ 3,000
$13,730
10 760
30
6,520
--
1,050
$32,090
$0.39 (0.35)
199
-------
TABLE 80. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Anode Cooling
MODEL PLANT ANNUAL CAPACITY: 81,660 MT (89,800 ST)
TREATMENT ALTERNATIVE: Settle, cool, recycle^
Facilities:
Settling pits (2) 18 m3 ea. 3 x 3 x 2 m $ 6,200
Holding pits 105 m3 3 x 5 x 7 m 13,700
80 m3 3 x 5 x 5.3 m 10,500
Equipment:
Cooling tower 3,030 1/min. 25 Hp 8,000
Pumps 3+1 water pumps 3,500 1/min $3,400 - 35 HP ea. 13,600
Piping 200 m of 20 cm pipe at $40/m 8,000
Labor:
12 hrs/week, 50 weeks/yr at $12/hr 7.200
Sludge Disposal:
5 MT/yr 30
EnergyL
130 Hp, 6 hrs/day, 5.5 days/wk, 50 wks/yr 6,520
Land:
0.2 ha at $15,000/ha 3,000
200
-------
TABLE 81.
MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Anode Cooling
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 81 > 66° m
PLANT WASTEWATER FLOW: 3,030 1/min, 6 hrs/day, 5.5
(89,800 ST)
days/wk
TREATMENT ALTERNATIVE: Settle, discharge to POTW
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
$36,800
4,000
3,600
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
6,700
1,200
$52,300
LAND ($)
1,500
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
$ 5,740
2,680
30
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
520
$8,970
COST PER METRIC (SHORT) TON OF PRODUCT ($)
-------
TABLE 82. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Anode Cooling
MODEL PLANT ANNUAL CAPACITY: 81,660 MT (89,800 ST1
TREATMENT ALTERNATIVE: Settle, discharge to POTW
Facilities:
Settling pit 1,200 m3 20x 20x 3 $36,800
Equipment:
Piping 100 m of 20 cm pipe at $40/m 4,000
Labor:
2 hrs/week, 50 weeks/yr at $12/hr 1,200
Sludge Disposal:
5 MT/yr 30
Land:
0.1 ha at $15,000/ha Ij50o
202
-------
TABLE 83. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Emission scrubber water
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 81^660 MT (pfan^l
PLANT WASTEWATER FLOW: 22.7 m3/hr, ?4 hrs/Hav'800 £?
TREATMENT ALTERNATIVE: Neutralization, settle, cool,
dav<;/mo
sludge dewater,
recycle
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT ($)
79,400
67,900
800
32,000
23.800
$269,400
$ 4,500
$ 35,680
47,330
1,050
6,260
3,540
2,690
$ 96,550
$1.18 (1.07)
203
-------
TABLE 84. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Emission scrubberwater
MODEL PLANT ANNUAL CAPACITY: 81,660 MT (89,800 ST)
TREATMENT ALTERNATIVE: Neutralization, settle, cool, sludge dewater, recycle
Facilities:
Building $4,400
Settling pits (2) 545 m3 11 x 10 x 5 m 54,800
Holding pits 11.7 m3 1.2 x 2.4 x 4 3,500
9.2 m3 1.2 x 2.4 x 3.2 2,800
Equipment:
Lime neutralization system 6.5 Hp 20,000
Cooling tower 4, Hp 3,600
Pumps
3+1 water pumps 400 1/min $1500-6 Hp ea 6,000
1+1 slurry pumps 2500-2 Hp ea 5,000
Piping
200 m of 10 cm pipe at $24/m 4,800
Centrifuge 2-Hp 40,000
Labor:
12 hrs/day, 264 days/yr at $12/hr 38,000
Sludge Disposal
210 MT/yr L050
Energy:
.32.5 Hp, 24 hrs/day, 264 days/yr 6,260
Material:
Hydrated lime (0.32 Kg/m3) 46 MT/yr at $77/MT 3,540
Land:
0.3 ha at $15,000/ha 4,500
204
-------
TABLE 85. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Emission Scrubber Water
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 10,910 MT
(Med.Plant)
PLANT WASTEW ATE R FLOW: 1,440 m3/da; 250 days7yr°° S *
TREATMENT ALTERNATIVE: Neutralization, settle, sludge
dewater, recycle
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
$28,800
86,900
74,200
900
28,600
26,100
$245,500
LAND ($)
$ 3,000
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
$ 34,030
32,920
2,500
10,210
8,860
2,460
$ 90.980
COST PER METRIC (SHORT) TON OF PRODUCT ($)
$8.34 f7.581
205
-------
TABLE 86. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Emission scrubber water
MODEL PLANT ANNUAL CAPACITY: 10,910 MT (12,000 ST)
TREATMENT ALTERNATIVE: Neutralization, settle, sludge dewater, recycle
Facilities:
Settling basins (2) 79 in3 ea 24.4 x 1.8 x 1.8 $24,400
Building 4,400
Equipment:
Lime neutralization system 8Hp 25,700
Storage tank 10 nr 3,400
Centrifuge 2 Hp 40,000
Pumps
3+1 water pumps 1200 1/min $2,000 - 15 Hp ea 8,000
1+1 slurry pumps 120 1/min $2,500 - 1 Hp ea 5,000
Piping 150 m of 15 cm pipe at $32/m 4,800
Labor:
8 hrs/day, 250 days/yr at $12/hr 24,000
Sludge Disposal:
500 MT/yr 2,500
Energy:
56 Hp, 24 hrs/day, 250 days/yr 10,210
Materials:
Hydrated lime (0.32 Kg/m3) 115 MT/yr at $77/MT 8,860
Land:
0.2 ha at $15,000/ha 3,000
206
-------
TABLE 87. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY; Secondary Copper
PROCESS: Emission scrubber water (Phosphorus)
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 1,550 MT (1680 ST)
PLANT WASTEWATER FLOW: 945 1/hr, 16 hrs/day, 250 days/yr
TREATMENT ALTERNATIVE: Neutralize, settle, recycle
INVESTMENT <$}
FACILITIES $10*400
207
EQUIPMENT 28,300
INSTALLATION 22,100
TRANSPORTATION 30°
CONTINGENCY AND FEE 9,200
ENGINEERING 8,500
TOTAL INVESTMENT 78,800
LAND ($) $ 1.500
ANNUAL COSTS ($)
AMORTIZATION $10.870
OPERATION AND MAINTENANCE 14.830
SLUDGE/SLAG DISPOSAL 5.050
ENERGY 1.580
MATERIALS 1,160
TAXES AND INSURANCE
TOTAL ANNUAL COSTS 34,260
COST PER METRIC (SHORT) TON OF PRODUCT ($) 22.59 (20.56)
-------
TABLE 88. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Emission scrubber water (Phosphorus)
MODEL PLANT ANNUAL CAPACITY: 1530 MT )1680 ST)
TREATMENT ALTERNATIVE: Neutralize, settle, recycle
Facilities:
Building $4,400
Settling pits (2) 16 nr1 ea 4 x 2 x 2 m 6,000
Equipment:
Lime neutralization system 4 Hp 13,900
Pumps
3+1 water pumps 100 1/min. $1200 - 2 Hp ea 4,800
1+1 slurry pump 2500 - 1 Hp ea 5,000
Piping
100 m of 10 cm pipe at $24/m 2,400
Centrifuge 2 Hp 2,200
Labor:
6 hrs/day, 250/days/yr at $12/hr 12,000
Sludge Disposal:
1,060 MT/yr 5,030
Material:
Hydrated lime (4 Kg/m3) 15MT/yr at $77/MT 1,160
Energy:
13 Hp, 16 hrs/day, 250 days/yr 1,580
Land:
0.1 ha at $ 15,000/ha 1,500
208
-------
TABLE 89. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS- Emission scrubber water
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 81>660 m (Large Plant)
PLANT WASTEWATER FLOW: 22. 7 m3/hr. 24 hrs/d. 22
TREATMENT ALTERNATIVE: Neutralization, settle
days /mo (89,600 ST)
, sludge dewater, discharge
to POTW
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND (S)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT ($>
$59,200
71,600
60,800
700
28,800
21,500
$242,600
$ 4,500
$ 32,130
40,080
1,050
3,180
3,540
2,430
$82,410
$1.01 (0.92)
209
-------
TABLE 90. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Emission scrubber water
MODEL PLANT ANNUAL CAPACITY: 81,660 MT [89,600 ST)
TREATMENT ALTERNATIVE: Neutralization, settle, sludge dewater, discharge to
P'OTW
Facilities:
Building $ 4,400
Settling pits (2) 545 m3 11x10x5 54,800
Equipment:
Lime neutralization system 6.5 Hp 20,000
Pumps
1+1 water pumps C400 1/min) $1500 - 6 Hp ea 3,000
1+1 slurry pump 2500 - 2 Hp ea 5,000
Piping 150 m of 10 cm pipe at $24/m 3,600
Centrifuge 2 Hp 40,000
Labor:
10 hrs/day, 264 days/yr at $12/hr 31,680
Sludge Disposal:
210 MT/yr 1,050
Energy:
16.5 Hp, 24 hrs/day, 264 days/yr 3,180
Material:
Hydrated lime (0.32 Kg/m3) 46 MT/ yr at $77/MT 3,540
Land:
0.2 ha at $15,000/ha 3,000
210
-------
TABLE 91.
MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Emission scrubber water
PI ANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: ] 0, 91 « MT
PI AMT WASTEWATER FLOW: 1 > 44° **/***'> 250 da/S/yr
TREATMENT ALTERNATIVE: Neutralization, settle, sludge
to mi w
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY _
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT ($)
(MH plant (12,000 Sp
dewater, discharge
$28,800
79,900
67,900
800
26,600
24,000
$728 000
$ 3,000
$ 31,500
32.250
2,500
7,470
8,860
2,?sn
$84,860
$7.78 (7.07)
211
-------
TABLE 92. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Emission scrubber water
MODEL PLANT ANNUAL CAPACITY: 10,910 MT (12,000 ST)
TREATMENT ALTERNATIVE: Neutralization, settle, sludge dewater, discharge
to POTW
Facilities:
Settling basins (2) 79 m3 ea 24.4x1.8x1.8 $24,400
Building 4,400
Equipment:
Lime neutralization system 8 Hp 25,700
Centrifuge 2 Hp 40,000
Pumps
2+1 water pumps 1200 1/min. $2,000-15 Hp ea 6,000
1+1 slurry pumps 120 1/min. $2500 - 1 Hp ea 5,000
Piping 100 m of 15 cm pipe at $32/m 3,200
*
8 hrs/day, 250 days/yr at $12/hr 24,000
Sludge Disposal:
500 MT/yr 2,500
Energy:
41 Hp, 24 Hrs/day, 250 days/yr 7,470
Materials:
Hydrated lime (0.32 Kg/m3) 115 MT/yr at $77/MT 8,860
Land:
0.2 ha at $15,000/ha 3,000
212
-------
TABLE 93. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
Emission scrubber water (Phosphorus)
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: I530 OT (1,680 ST)
PLANT WASTEWATER FLOW: 945 X/hr> 16 hrs/day, 250 days/yr
TREATMENT ALTERNATIVE: Neutralize, settle, discharge to
POTW
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND 1$)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
$10,400
25,900
20,000
300
8,500
7,800
77,700
$ 1,500
$10.020
14.610
5.030
1.540
1,160
730
32,890
COST PER METRIC (SHORT) TON OF PRODUCT ($)
$21.50 f 19. 541
213
-------
TABLE 94. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Emission scrubber water CPhosphorousj
MODEL PLANT ANNUAL CAPACITY: 1530 MT (1.680 ST)
TREATMENT ALTERNATIVE: Neutralize, settle, discharge
Facilities:
Building $4j400
Settling pits (2) 16 nr5 ea 4x2x2 6,000
Equipment:
Lime neutralization system 4Hp 13,900
Pumps
2+1 water pump 100 1/min. $1,200 - 2 Hp ea 3,600
1+1 slurry pump, 2,500 - 1 Hp 5,000
Centrifuge 2 Hp 2,200
Piping
50 m of 10 cm pipe at $24/m 1,200
Labor:
4 hrs/day, 250 days/yr at $12/hr 12,000
Sludge Disposal:
1,060 MT/yr 5)030
Materials:
Hydrated lime (4 Kg/m3) 15 MT/yr at $77/MT 1,160
Energy:
11 Hp, 16 hrs/day, 250 days/yr 1,340
Land:
0.1 ha at $15,000/ha 1,500
214
-------
TABLE 95. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Slag Granulation
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 16,525 NfT (17,950 ST)
PLANT WASTEWATER FLOW: 205 1/min, 24 hrs/day, 130 days/yr
TREATMENT ALTERNATIVE: Settle, cool, recycle
INVESTMENT ($)
FACILITIES $ 12,700
EQUIPMENT 13.000
INSTALLATION 10,400
TRANSPORTATION 100
CONTINGENCY AND FEE 5.400
ENGINEERING 3.900
TOTAL INVESTMENT $ 45.500
LAND 1$) $ 1,500
ANNUAL COSTS ($)
$ 5,950
AMORTIZATION
OPERATION AND MAINTENANCE 7>79°
SLUDGE/SLAG DISPOSAL II
ENERGY 1,250
MATERIALS I
TAXES AND INSURANCE 460
TOTAL ANNUAL COSTS $ 15.450
COST PER METRIC (SHORT) TON OF PRODUCT ($) $0.95 C$0.86')
215
-------
TABLE 96. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Slag Granulation
MODEL PLANT ANNUAL CAPACITY: 16,325 MT (17,950 ST)
TREATMENT ALTERNATIVE: Settle, cool, recycle
Facilities:
Settling pits (2) 26 m 3.6 x 3.6 x 2 m $7,400
Holding pits 12 m3 2 x 2 x 3 m 3,000
9m 2x2x2.3m 2,300
Equipment:
Cooling tower 205 1/min 5 HP 4,000
Pumps
2 +• 1 water pumps 250 1/min $1,400 - 4 HP ea. 4,200
Piping 200 m of 10 cm pipe $24/m 4,800
Labor:
4 hrs/day, 130 hrs/yr at $12/hr 6,240
Energy:
13 HP, 24 hrs/day, 130 days/yr 1,230
Land:
0.1 ha at $15,000/ha 1,500
216
-------
TABLE 97. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS- Slag Granulation
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 16.525 MT (17,950 ST)
PLANT WASTEWATER FLOW: 205 I/"*". 24 hrs/day. 130 days/yr
TREATMENT ALTERNATIVE: Lime treatment, settle, discharge to POTW
INVESTMENT ($)
FACILITIES 1—7,400
EQUIPMENT 27,500
INSTALLATION 21,100
TRANSPORTATION 22i_
CONTINGENCY AND FEE 8,400
ENGINEERING 8i.2P0
TOTAL INVESTMENT
TAXES AND INSURANCE
217
$ 72.700
LAND ($) $ 1.5QQ
ANNUAL COSTS ($)
$ 10,140
AMORTIZATION
5,760
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL :
ENERGY
MATERIALS 89°.
$ 18,470
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT ($) $1.15 C$1.051
-------
TABLE 98. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Slag Granulation
MODEL PLANT ANNUAL CAPACITY: 16,325 MT (17,950 ST)
TREATMENT ALTERNATIVE: Lime treatment, settle, discharge to POTW
Facilities:
Settling Pits (2) 26 m3 3.6 x 3.6 x 2 m $ 7,400
Equipment:
Lime neutralization system 5 HP 17,100
Pumps 1+1 water pumps 205 1/min $1,400 - 4 HP ea. 2,800
1+1 slurry pump $2,500 - 1 HP ea. 5,000
Piping
100 m of 10 cm pipe at $24/m 2,400
Labor:
2 hrs/day, 130 days/yr at $12/hr 3,120
Energy:
10 HP, 24 hrs/day, 130 days/yr 950
Materials:
0.3 Kg/m3, 11.5 MT/yr at $77/MT 890
Land:
0.1 ha at $15,000/ha 1,500
218
-------
TABLE 99. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS: Electrolyte waste water
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 81>660
m (89,800 ST) (Large Plar
PLANT WASTEWATER FLOW: 5.9m3/hr, 24 hrs/day, 360 days /yr
TREATMENT ALTERNATIVE: Neutralization, settling,
ing, recycle
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING.
TOTAL INVESTMENT
LAND ($>
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT {$)
filtration, sludge, dewate
$27,000
87,700
75,300
900
28,600
26,300
$245,800
$ 3,000
$ 34,160
46,760
71,870
5,510
26,720
2,460
$187,480
$2.30 (2.09)
t)
r-
219
-------
TABLE 100. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Electrolyte waste water
MODEL PLANT ANNUAL CAPACITY: 81,660 MT (89,800 ST)
TREATMENT ALTERNATIVE: Neutralization, settling, filtration, sludge,
dewatering, recycle
Facilities:
Building $ 4,400
Settling pits (2) 150 m3 10 x 5 x 3 m 22,600
Equipment:
Lime neutralization system 12 Hp 27,100
Filter 3,200
Pumps
3+1 water pump 150 I/ min. $1500 - 2 HPea 6,000
1+1 slurry pump 100 I/ min. $2500 - 1 HP 5,000
Centrifuge 2 Hp 40,000
Piping
200 m of 15 cm pipe at $32/m 6,400
Labor:
9 hrs/day, 350 days/yr at $12/hr 37,800
Sludge Disposal:
14,375 MT/yr 71,870
Materials:
Hydrated lime (6.8 Kg/m3) 347 MT at $77/MT 26,720
Energy:
21 Hp, 24 hrs/day, 360 days/yr 5,510
Land:
0.2 ha at $15,000/ha 3,000
220
-------
TABLE 101. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS- Electrolyte wastewater
P( ANT ANNIIAI CAPACITY ifj MfTRir (SHORT) TONS: 32,700MT (35 , 970 ST) (Med . Plant
PLANT WASTEWATER FLOW: 4 m3/hr8< 24 hrs/day, 250
TREATMENT ALTERNATIVE: Neutralization, settling
dewatering, recycle
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT <$)
days/yr
, filtration, sludge.
$20,800
82,000
70.500
800
26,100
24,600
$224,800
$ 3,000
$ 31,430
26,250
35,280
3,010
17,560
2,250
$115,780
$3.54 (3.221
221
-------
TABLE 102. COST COMPONENTS
INDUSTRY: Secondary Copper
PRQCESS: Electrolyte Waste Water
MODEL PLANT ANNUAL CAPACITY.- 32,700 MT (55,970 ST)
TREATMENT ALTERNATIVE: Neutralization, settling, filtration, sludge,
dewatering, recycle
Facilities:
Building $ 4,400
Settling pits (2) 100 m3 J.O x 5 z 2 m 16,400
Equipment:
Lime neutralization system 7,5 Hp 22,600
Filter 3,200
Pumps
3+1 water pump 100 1/min. $ 200 - 2 Hp ea 4,800
1+1 slurry pump 100 1/min. 2500 - 1 Hp ea 5,000
Centrifuge 2 Hp 40,000
Piping
200 m of 15 cm pipe at $32/m 6,400
Labor:
6 hrs/day, 250 days/yr at $12/hr 18,000
Sludge Disposal
7,055 MT/yr 35,280
Materials:
Hydrated lime (6.8 Kg/m3) 228 MT/yr at $77/MT 17,560
Energy:
16.5 Hp, 24 hrs/day, 250 days/yr 3,010
Land :
0.2 ha at $15,000/ha 3,000
222
-------
TABLE 103. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROTESS- Electrolyte Waste Water
PLANT ANNUAI CAPACITY IN MFTRIC (SHORT) TOMS- 81,660 MT (89,800
PlrtNTW^«yAT«p,n«. 5.9 m3/hr, 24 hrs/day, 360 days/yr
TBCATMPMT A. TFRNATIVE: Neutralization, settling, filtration,
dewatering, discharge to POTW
INVbSTMENT ($)
CAPII |TIF*5 - -
Cftl IIPMFMT
INol ALLMIIUnl - ••
TO AMQDrtDTATirtM
Pf^MTIMfiPMPV AMD FFF
cMniMrrniMP. ,
TYYTAI IM\/F«5TMFMT . ,. .
LANl/ (91 "
ANNUAL COSTS ($)
AMUK 1 l£A 1 lUrV — •- •
nnrn ATiriM AMH MAlhlTFMAMPF
K/IATFRI A 1 <5
TAVF«! AMD IM^IIRANrF . _ , .. ..
THTAI &NNIIAI PO^T^ . .
rn
-------
TABLE 104. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS : Electrolyte Waste Water
MODEL PLANT ANNUAL CAPACITY: 81,660 MT f89,800 ST1
TREATMENT ALTERNATIVE: Neutralization, settling, filtration, sludge
dewatering, discharge to POTW
Facilities :
Building $ 4 40Q
Settling pits (2) 10x5x3 m 22,'eoo
Equipment :
Lime neutralization system 12 Hp 27 100
Filter *
Pumps
2+1 water pumps 150 1/min $1500 - 2Hpea 4 500
1+1 slurry pump 100 1/min 2500 - 1 Hpea 5,'oOO
2H» 4
150 m of 15 cm pipe at $32/m 4,800
Labor :
9 hrs/day 350 days/yr at $12/hr 37,800
Sludge Disposal:
14.375 MT/year 71j870
Materials:
Hydrated lime (6.8 Kg/m3) 347 MT at $77/MT 26,720
Energy :
19 Hp 24 hrs/day, 360 days/yr 4,990
Land:
0.2 ha at $15,000/ha 3j000
224
-------
TABLE 105. MODEL-PLANT CONTROL COSTS FOR
INDUSTRY: Secondary Copper
PROCESS- Electrolyte WaSte Water
PLANT ANNUAL CAPACITY IN METRIC (SHORT) TONS: 32,700 MT (35,970 ST) [Med.Plam
PI ANT WASTFWATER FLOW: 4 m3/hr, 24 hrs/day, 250
TREATMENT ALTERNATIVE: Neutralization, settling
dewatering, discharge to
INVESTMENT ($)
FACILITIES
EQUIPMENT
INSTALLATION
TRANSPORTATION
CONTINGENCY AND FEE
ENGINEERING
TOTAL INVESTMENT
LAND ($)
ANNUAL COSTS ($)
AMORTIZATION
OPERATION AND MAINTENANCE
SLUDGE/SLAG DISPOSAL
ENERGY
MATERIALS
TAXES AND INSURANCE
TOTAL ANNUAL COSTS
COST PER METRIC (SHORT) TON OF PRODUCT ($)
days/yr
. filtration, sludge
POTW
$20,800
79,200
68,000
800
25,300
23,800
$217,900
$ 3,000
$ 30,440
25,980
35,280
2,640
17,560
2,180
$114,080
$3.49 f3.17~)
225
-------
TABLE 106. COST COMPONENTS
INDUSTRY: Secondary Copper
PROCESS: Electrolyte Waste Water
MODEL PLANT ANNUAL CAPACITY: 32,700 MT (55.970 ST)
TREATMENT ALTERNATIVE: Neutralization, settling, filtration, sludge,
dewatering, discharge to POTW
Facilities:
Building $ 4>400
Settling pits (2) 100 m3 10x5z2 m 16,400
Equipment:
Lime neutralization system 7.5 Hp 22 600
Jilter 3^200
Pumps
2+1 water pump $1200 - 2 Hp ea 3,600
1+1 slurry pump 2500 - 1 Hp ea 5,QOO
Piping
150 m of 15 cm pipe at $32/m 4,800
Centrifuge 2 Hp 40,000
Labor:
6 hrs/day, 250 days/yr at $12/hr 18,000
Sludge Disposal:
7,055 MT/yr 35j280
Materials:
Hydrate lime (6.8 Kg/m3) 228 MT/ yr at $77/MT 17,560
Energy:
14.5 Hp, 24 hrs/day, 250 days/yr 2,640
Land:
0.2 ha at $15,000/ha 3j000
226
-------
Table 107
COST-EFFECTIVENESS OF TREATMENT AND CONTROL ALTERNATIVES
NJ
A. METAL COOLING WATER
TREATMENT OR CONTROL
COARSE
SETTLING & DISCHARGE
FINE
SETTLING & DISCHARGE
SETTLE, STORE
AND RECYCLE
SETTLE, COOL, RECYCLE
SETTLE, COOL, FILTER,
RECYCLE
COST. $/MT PRODUCT
SMALL PLANT
C
0
1.98
2.38
-
_
NC
0
0.97
1.42
-
..
MEDIUM PLANT
C
0
1.05
1.57
-
3.27
NC
0
0.55
0.82
-
„
LARGE PLANT
C
0
1.09
..
-
1.76
NC
0
0.74
_
1.07
_
EFFLUENT CONCENTRATIONS, mg/l
OIL&
GREASE
<2.0
Cu
1.2
Zn
1.7
Pb
0.70
Cd
<.01
Hg
<.0006
NO DATA AVAILABLE ON EFFECTIVENESS
"^
0 - NO EFFLUENT DISCHARGE — *
0 - NO EFFLUENT DISCHARGE — >
0 - NO EFFLUENT DISCHARGE — >
B. FURNACE EXHAUST SCRUBBING WATER
TREATMENT OR CONTROL
NO TREATMENT
SETTLING, DISCHARGE
LIME OR CAUSTIC AND
SETTLING, DISCHARGE
LIME OR CAUSTIC, SETTLING
COOL. AND RECYCLE
SMALL PLANT
0
-
21.50
22.39
MEDIUM PLANT
0
--
7.78
8.34
LARGE PLANT
0
-
1.01
1.18
OIL&
GREASE
<30
< 5
<5
Cu
174
22
0.20
(
Zn
475
89
2
TOTAL
Pb
472
13
0.06
.)
Cd
4.0
3.2
0.02
Hg
0.003
<.001
<.001
< 0- NO EFFLUENT DISCHARGE >
C- CHARCOAL COVER
NC- NO CHARCOAL COVER
-------
Table 107. (continued)
COST-EFFECTIVENESS OF TREATMENT AND CONTROL ALTERNATIVES
oo
TREATMENT OR CONTROL
NO TREATMENT, DISCHARGE
(AFTER IRON CEMENTATION)
NEUTRALIZATION AND SETTLING
FILTRATION, DISCHARGE
NEUTRALIZATION AND SETTLING
FILTRATION AND RECYCLE
C. ELECTROLYTE WASTEWATER
COST. $/MT PRODUCT
SMALL PLANT
0
-
-
MEDIUM PLANT
0
3.49
3.54
LARGE PLANT
0
2.27
2.30
EFFLUENT CONCENTRATIONS, mg/l
OIL&
GREASE
< 1
<1
Cu
6.87
0.20
(
< 0-NOEFF
Zn
175
2
TOTAL
LUEN1
Pb
1.0
0.06
I
Cd
1.3
0.02
' DISCHARGE
Hg
__
<.001
D. SLAG GRANULATION WATER
TREATMENT OR CONTROL
COARSE SETTLING, DISCHARGE
(NO ADDED TREATMENT)
LIME TREAT, SETTLE,
DISCHARGE
SETTLING, COOLING, RECYCLE
SMALL PLANT
-
-
-
MEDIUM PLANT
-
-
-
LARGE PLANT
0
1.13
0.95
OIL&
GREASE
-
Cu
0.07
r
Zn
0.06
rOTAL
Pb
0.2
"
Cd
0.07
Hg
< 0.0003
NO DATA AVAILABLE ON EFFECTIVENESS
< 0- NO EFFLUENT DISCHARGE *
-------
Table 108 ESTIMATED ADDITIONAL TREATMENT AND CONTROL NEEDS
FOR SECONDARY COPPER POTW DISCHARGERS
PLANT CODE
PRETREATMENT FOR DISCHARGE
TO POTW
TREATMENT AND CONTROL FOR
ZERO DISCHARGE
1
2
3
4
5
8
9
10
11
12
13
14
15
16
17
18
19
Settling of metal cooling water (Table 43)
Settling of metal cooling water (Table 43)
Settling of shot quenching water (Table 63)
Settling of metal cooling water (Table 45)
Lime treatment and settling of emission
scrubwater; settling of billet and anode
cooling water. Neutralization, settling
and filtration of electrolyte waste water
(Tables 77. 81, 89. 103)
Settling of metal cooling water (Table 43)
Settling of metal cooling water (Table 57)
Settling of metal cooling water (Table 57)
Settling of metal cooling water; neutraliza-
tion and settling of phosphor copper furnace
emission scrubwater; settling of shot
quenching water; lime treat and settling of
slag granulation water (Tables 55,93,97)
Neutralization and settling of emission
scrubwater (Table 93)
Settling of metal cooling water (Table 45)
Lime treat and settling of shot quenching
water (Table 71)
Settling of metal cooling water (Table 59)
Settling of metal cooling water (Table 45)
Settling of metal cooling water (Table 57)
Settling of metal cooling water (Table 59 &
43)
Lime treatment and settling, of phosphor
copper scrubwater in conjunction with
aluminum smelter wastes (chlorine
demagging water) (Table 73)
Store, recycle metal cooling water (Table 37)
Store, recycle metal cooling water (Table 37)
Store, recycle, shot quenching water (Table 61)
Store, recycle metal cooling water (Table 39)
Lime treatment, settling, cooling and recycle
of emission scrubwater; store and recycle
billet cooling water. Neutralization, settling,
filtration and recycle of electrolyte wastewater.
(Tables 75, 79,84, 99)
Store, recycle metal cooling water (Table 37)
Store, recycle metal cooling water (Table 51)
Store, recycle metal cooling water (Table 51)
Settle, cool, filter and recycle metal cooling
water; neutralize settle, and recycle phosphor
copper furnace emission scrubwater; store and
recycle shot quenching water; settle cool and
recycle slag granulation water (Tables 47,88,95]
Neutralize, settle, and recycle emission
scrubwater (Table 88)
Store, recycle metal cooling water (Table 39)
Lime treat, settle, recycle shot quenching
water and emission scrubwater (Table 69)
Store, recycle metal cooling water (Table 53)
Store, recycle metal cooling water (Table 39)
Store, recycle metal cooling water (Table 51)
Settle, cool, filter, recycle metal cooling water
(Tables 37, 53)
Not applicable
229
-------
Table 109
ESTIMATED COSTS OF ADDITIONAL TREATMENT AND CONTROL TO SECONDARY
COPPER POTW DISCHARGERS
to
u>
o
PLANT
CODE
1
2
3
4
5
8
9
10
11
12
13
14
15
16
17
18
19
ANNUAL
MODEL PLANT
CAPACITY
(9.820 MT)
(9,820 MT)
( 380 MT)
(3,275 MT)
(81,660 MT)
(9,820 MT)
(9,820 MT)
(9,820 MT)
(23,000 MT)
(1,530 MT)
(3,275 MT)
(820 MT)
(3.275 MT)
(3.275 MT)
(9,820 MT)
(13.095 MT)
(650 MT)
TOTALS
TREATMENT COSTS (PH ADJUSTMENT & SETTLE
CAPITAL
$13,200
13,200
2,200
8,000
547,500
13,200
13.200
13,200
147.600
74,400
8,000
152,100
8,000
8,000
13,200
21,200
4,600
$1,060,800
ANNUAL
$5.360
5,360
640
3,170
278,320
5,360
10,310
10,310
76,090
32,890
3,170
43,330
6,470
3,170
10,310
11,830
880
$506,610
$/METRIC TON
$ 0.55
0.55
1.68
0.97
3.41
0.55
1.05
1.05
3.31
21.50
0.97
52.84
1.98
0.97
1.05
0.90
1.35
CONTROL COSTS (RECYCLE)
CAPITAL
$24,200
24,200
10,200
14,000
641,900
24,200
24,200
24,200
199,900
80,300
14,000
176,400
13.300
14,000
24,200
37,500
4,600
$1,351.300
ANNUAL
$8,040
8,040
2.110
4,650
318,790
8,040
15,400
15,400
89,740
34,260
4,650
59,250"!
7,810
4,650
15,410
15,850
880
$612,960
$/METRICTON
$ 0.82
0.82
5.55
1.42
3.90
0.82
1.57
1.57
3.90
22.39
1.42
25.21 1
2.38
1.42
1.57
1.21
1.35
1
BASED ON CAPACITY OF 2350 MT
-------
SECTION IX
BEST PRACTIBLE PRETREATMENT TECHNOLOGY
Introduction
The best practicable pretreatment technology is based on the
best performance by plants of various sizes and ages, as
well as the unit processes within the industrial category.
The experience of other plants producing chemically and
metallurgically similar waste streams is also drawn upon.
Additional consideration was also given to:
(1) The total cost of application of
technology in relation to the effluent
reduction benefits to be achieved
from such application.
(2) The size and age of the equipment and
plant facilities involved.
(3) The process employed.
(4) The engineering aspects of the
application of various types of
control techniques.
(5) Process changes.
(6) Nonwater quality environmental
impact (including energy requirements).
The best practicable pretreatment technology emphasizes
effluent treatment at the end of a manufacturing process.
It includes the control technology within the process itself
when the latter is considered to be normal practice within
the industry.
Industry Categorization and Waste Water Streams
The secondary copper industry is herein defined as that
segment of the copper industry which recovers copper metal
and copper alloys from copper scrap and residues, as
established in 40 CFR 421.60. The definition includes
plants melting and refining copper alloys from secondary
brass and secondary bronze scrap sources to produce alloyed
copper ingots, as well as those melting and refining
purchased copper-bearing scrap to recover pure copper
(unalloyed copper). This category is not intended to
include plants that are designed primarily to process virgin
copper from ores, plants that remelt scrap produced in their
own process, or foundries that do not perform refining
operations.
231
-------
As developed in Section IV of this document, the secondary
copper industry is considered as a single subcategory for
the purpose of establishing pretreatment standards. The
principal basis for this consideration is the similarity of
process waste water characteristics and available control
and treatment technologies throughout the industry.
The process waste water sources from that portion of the
secondary copper industry discharging to POTW include:
(1) Waste water from direct contact cooling
of metal (ingots, anodes, billets, or
shot) ;
(2) Waste water from slag quenching and
granulation;
(3) Waste water from wet air pollution
control systems; and
(4) Waste water from electrolytic refining.
Pretreatment Standards
It was found that process waste water from contact metal
cooling, slag granulation, furnace exhaust scrubbing, and
electrolytic refining operations can be completely recycled
or reused to eliminate discharge. The application of this
recycle and reuse technology is recommended whenever such
?n~?° 5SL " con?istent with the aims and goals of the
local POTW operating authority. in cases where the
introduction of process waste waters from secondary copper
erS t the f0110^^ standards
P—-, „. - , _ Pretreatment Standard
Effluent Maximum for Average of daily
Characteristic any 1 day valuel for 30 *
consecutive days
— - — - - _ shall not exceed
Copper, mg/1 i.0 0 50
Cadmium, mg/1 Q.40 Q' 20
Oil and Grease, mg/1 100
232
-------
Identification of Best Practicable Pretreatment
Technology
The best practicable pretreatment technology available to
achieve these pretreatment levels is identified as chemical
treatment to achieve controlled precipitation followed by
sedimentation (e.g., pH adjustment and settling) with
skimming, where necessary, to control the levels of oil and
grease.
The regulated pollutants were selected following a
determination that they are not susceptible to treatment by
POTW or that they may interfere with the operation of POTW.
Other pollutants found in process waste water streams were
rejected on the basis that they do not pose a threat to
POTW, or that they are effectively treated by the same
pretreatment technology necessary to meet the identified
control levels. This analysis is presented in Section VI of
this document.
The pretreatment standards for the secondary copper industry
are set in the form of concentration standards rather than
mass loadings (e.g., kg of pollutant per kkg of product).
Available data on effluent flow rates was collected, but it
was found that these flow rates varied over extremely wide
ranges for like operations, and could not be correlated to
refined copper or brass and bronze metal production.
The end-of-pipe treatment identified is the pH adjustment
and settle treatment. Currently, some form of this
treatment is applied to some portion of process waste water
at at least two of the seventeen plants discharging to POTW.
However, this treatment is commonly applied elsewhere in
this industry, particularly at direct dischargers meeting
no-discharge limitations. The principles of the pH
adjustment and settle treatment technology are thus known to
most of the industry; however, the current application of
the technology is extended in some cases to considerably
less than all of the process waste water streams. As
reflected in Sections V and VII of this document, the
technology is applied with varying degrees of effectiveness,
depending on the care taken with the operation of the
neutralization facility. The pH adjustment and settle
treatment identified herein implicitly includes a "best
practicable pretreatment" level of performance, described in
terms of effluent concentrations.
The combination of pH adjustment and clarification achieves
the best practicable pretreatment technology. Clarification
alone will reduce only total suspended solids; pH adjustment
233
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without clarification will reduce dissolved metals, but not
total metals. pH adjustment with lime or caustic to a pH in
the 8 to 10 range will reduce the concentrations of those
metals precipitable as hydroxides, and with properly
designed retention facilities will also reduce total
suspended solids. Use of lime has the advantage in that it
unlike sodium-based alkalies, forms a relatively insoluble
sulfate, casoi, which will tend to also decrease the
concentrations of dissolved sulfate in the effluent.
In many cases, pH adjustment may not be necessary in order
to meet the pretreatment standards, some streams, such as
contact metal cooling water, slag granulation water, and
non-phosphor copper furnace scrubwater can be highly
alkaline, so that the required removal of metals may be
accomplished by sedimentation only.
Skimming is the technology identified for the control of oil
and grease in discharges to POTW. while only low levels of
oil and grease were found in the effluent streams sampled
and analyzed at indirect dischargers, high levels of this
pollutant have been found in the past in the process waste
waters of direct dischargers. The level of control above is
specified as a preventive measure, primarily to ensure that
slug doses of oil and grease are not discharged to POTW.
The effluent concentration standard for cadmium was selected
after an examination of the information presented in
Sections V, VII, and VIII of this document and the
information available from other metals-based industries
producing similar wastewater streams. Table 30 shows a
reduction in cadmium values in emissions scrubwater and slag
milling wastewater at Plant V from between 2 and 2.3 mg/1 to
0.07 mg/1 following lime addition and settling. Cadmium
values at a secondary lead smelter were decreased two orders
of magnitude by lime and settle treatment, from 0.83 mg/1 to
0.005 mg/1. Data from a primary zinc smelter, a primary
copper smelter, several secondary aluminum smelters, many
electroplating operations, and Plant R, a secondary copper
smelter (Table 34), show that effluent cadmium levels can be
kept to 0.06 mg/1 or lower when influent concentrations are
1 mg/1 or lower. Additionally, recent sampling data from an
electroplating operation with a pH adjustment and settling
treatment system show that this system can consistently
achieve 0.2 mg/1 of cadmium in the effluent stream. In
light of the foregoing, it was concluded that a con-
centration of 0.2 mg/1 of cadmium is routinely achievable
with pH adjustment and settling technology and represents
the most appropriate standard.
234
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The effluent concentration standard for copper was selected
after a similar review of available data from the secondary
copper smelting and other metals-based industries. Monthly
monitoring data from a well operated lime and settling
facility at Plant R (Table 33) shows that effluent
concentrations were kept to 0.47 mg/1 or below for five
consecutive months, although a higher average was recorded
in a sixth month when the average pH was allowed to drop to
8.5. Table 34 shows that the concentration of copper in a
mixed process wastewater stream at Plant R was decreased
from 38.a mg/1 in the influent to the treatment plant to
0.160 mg/1 in the effluent. Influent concentrations of 0.12
mg/1 and 0.11 mg/1 at a primary copper smelter and a primary
zinc smelter were decreased by lime and settle treatment to
0.09 mg/1 and less than 0.02 mg/lr respectively. Extensive
data from the electroplating industry show that an effluent
copper concentration of 0.5 mg/1 is routinely achievable
using pH adjustment and settling technology. Since this
value is consistent with the values observed elsewhere, 0.5
mg/1 was selected as the appropriate concentration standard
for copper.
Recycle and reuse of process waste water streams should also
be considered. A review of water use practices in various
plant systems has shown that recycle technology is widely
practiced in the industry. Of the forty-six secondary
copper smelters identified as currently in operation in this
country, seventeen discharge no process waste water as a
result of recycle practices. The Best Practicable
Technology Currently Available for the secondary copper
industry, promulgated on February 27, 1975, requires eleven
additional direct dischargers to achieve no discharge of
process waste waters by July 1, 1977. The seventeen plants
currently discharging to POTW all practice recycle to
varying degrees. As an economic matter (detailed in Section
VIII of this document), indirect dischargers may choose to
completely recycle all process waste waters rather than
install the pretreatment technologies identified.
Features of Best Practicable Pretreatment Technology
(1) The selected pH adjustment and settle technology is
capable of achieving significant reductions in
discharge of pollutants, as indicated by
industry-supplied data, as verified by the analysis
of samples collected on-site at plants where the
technology was applied, and as indicated by
experience with chemically and metallurgieslly
similar waste streams from other metals-based
industries.
235
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(2) The technology is compatible with industry
variations, including age and size of plant,
processes employed, raw material variations, plant
location, and nonwater quality aspects such as
energy consumption and solid waste generation.
(3) The technology, as an end-of-pipe treatment, can be
an add-on to existing plants, and need not affect
existing internal process and equipment
arrangements.
(4) The maximum daily concentrations of pollutants,
with the exception of oil and grease, are set at
twice the demonstrated daily value averaged over
thirty days. This factor of two was selected after
an assessment of the variability of demonstrated pH
adjustment settle technologies on metals-bearing
process waste streams. This technology is based on
a relatively stable chemical process which does not
appear to vary much beyond a 2 to 1 ratio.
(5) An alternative technology, complete recycle of
process waters to eliminate discharge, was also
identified. It was found that a substantial
portion of the secondary copper smelting industry
practices this technology, and that complete
recycle of process waters may be an economically
attractive alternative to the identified pH
adjustment and settle pretreatment technology.
236
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Total costs
On the basis of information contained in Section VIII of
this document, it is concluded that a capital cost of
$1,060,800 and an annual cost of $506,610 will be incurred
by plants currently discharging to POTW in order to install
pH adjustment and settle facilities necessary to comply with
the identified pretreatment control levels. Alternatively,
it is estimated that a capital cost of $1,351,300 and an
annual cost of $612,960 is necessary for all such plants to
recycle all process waste waters, thus eliminating present
discharges to POTW.
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SECTION X
ACKNOWLEDGEMENTS
The Environmental Protection Agency would like to
acknowledge the contributions of the staff of Calspan
Corporation, particularly Mr. Richard Leonard, Mr. Michael
Wilkenson, and Mr. Robert Lockemer, under the direction of
Dr. P. Michael Terlecky, Jr. , for their aid in the
preparation of this document.
The Project Officer, Geoffrey H. Grubfcs, would like to thank
his associates in the Effluent Guidelines Division, namely
Mr. Ernst P. Hall, Mr. Walter J, Hunt and Mr. John E. Riley
for their valuable suggestions and assistance.
The members of the working group/steering committee who
coordinated the internal EPA review are:
Mr. Ernst P. Hall, Working Group Chairman, Effluent
Guidelines Division
Ms. Margaret Stasikowski, Office of Research and
Development
Mr. Steven Singer, Office of Analysis and Evaluation
Mr. Lee DeHihns, Office of General Counsel
Mr. Don Wood, Office of Planning and Evaluation
Mr. Gary Otakie, Office of Water Programs
Mr. Elwood E. Forsht, Effluent Guidelines Division
Appreciation is also extended to the following companies and
corporations for assistance and cooperation provided in this
program:
Cerro Corporation
H. Kramer and Company
Sipi Metals Company
Milward Alloys
R. Lavin Company
Joseph Behr Company
Finally, we wish to acknowledge the contributions of Ms.
Nancy Zrubek and Ms. Kaye Starr of the word processing staff
and those of the secretarial and administrative staff of the
Effluent Guidelines Division who worked so diligently to
prepare, edit, publish and distribute this manuscript.
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SECTION XI
REFERENCES
1. Development Document For Interim Final Effluent
Limitations Guidelines and Proposed New Source
Performance Standards for the Secondary Copper
Subcategory of the Copper Segment of the Nonferrous
Metals Manufacturing Point Source Category. Mr. George
Thompson, Jr., Project Officer, Effluent Guidelines
Division, Office of Water and Hazardous Materials, U.S.
Environmental Protection Agency, EPA-440/1-74/032-C
Group I, Phase II, February, 1975.
2. Agronomic Controls Over Environmental Cycling of Trace
Elements, W.H. Alloway in Advances In Agronomy, V20, pp.
235-274, 1968.
3. Building Construction Cost Data 1975, Robert Snow Means
Company, Inc., 33rd Annual Edition.
4. Process Plant Construction Estimating Standards.
Richardson Engineering Services, Inc., Solano Beach,
California 1975.
5. Cost of Standard-Sized Reactors and Storage Tanks.
Reprint from Chemical Engineering, Revised November
1975.
6. Correspondence with the Johnston Equipment Co., Inc.,
Rochester, New York. Representatives of Marley
Corporation, May 1976.
7. Telcom. with Calgon Corporation, Water Management
Division, Pittsburgh, Pennsylvania, May 1976.
8. Telcom. with Sethco Manufacturing Corporation, Freeport,
New York, June 1976.
9. Telcom. and Correspondence with Laval Separator
Corporation, Fresno, California, May 1976.
10. Telcom. and Correspondence with A.M. Lavin Machine
Works, Hatboro, Pennsylvania, May 1976.
11. Telcom. and Correspondence with Bird Machine Company,
So. Walpole, Massachusetts, May 1976.
12. Telcom. with Denver Equipment Company, May 1976.
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13. Capital and Operating Costs of Pollution Control
Equipment Modules. Vol. 1, User Guide, EPA-R5-73-023A,
July 1973.
14. Telcom. with Bison Laboratories, Inc., Buffalo, New
York, May 1976.
15. Telcom. with NALCO Chemical Company, Oakbrook, Illinois,
June 1976.
16. Development Document for Interim Final Effluent
Limitations Guidelines and Proposed New Source
Performance Standards for the Primary Copper Smelting
Subcategory and the Primary Copper Refining Subcategory
of the Copper Segment of the Nonferrous Metals
Manufacturing Point Source Category. Mr. George
Thompson, Jr., Project Officer, Effluent Guidelines
Division, Office of Water and Hazardous Materials, U.S.
Environmental Protection Agency, EPA-440/1-75/032-b,
February, 1975.
17. Development Document for Proposed Effluent Limitations
Guidelines and New Source Performance Standards for the
Copper, Nickel, Chromium and Zinc Segment of the
Electroplating Point Source Category. Mr. Harry M.
Thron, Jr., Project Officer, Effluent Guidelines
Division, U.S. Environmental Protection Agency, EPA-
440/1-73-003, August 1973.
18. Development Document for Effluent Limitations Guidelines
and New Source Performance Standards for the Copper,
Nickel, Chromium and Zinc Segment of the Electroplating
Point Source Category, Ms. Kit R. Krickenberger, Project
Officer, Effluent Guidelines Division, Office of Water
and Hazardous Materials, U.S. Environmental Protection
Agency, EPA-440/1-74-003-a, June, 1975.
19. Spendlove, Max J., Retired, Bureau of Mines, Private
Communication.
20. "Copper Industry in December, 1972", Mineral Industry
Surveys, U.S. Dept. of Interior, Bureau of Mines,
Washington, D.C., (February 28, 1973).
21. "Copper Industry in July, 1973", Mineral Industry
Surveys, U.S. Dept. of Interior, Bureau of Mines,
Washington, D.C., (September 28, 1973).
22. Rombert, B., Operations in the Nonferrous Scrap Metal
Industry Today, Fine, P., Rasher, H.W., and Wakesberg,
242
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Si (Eds.) published by the National Association of
Secondary Material Industries (1973).
23. Spendlove, Max J., "Methods for Producing Secondary
Copper", U.S. Dept. of interior, Bureau of Mines
Information Circular 8002 (1961).
24. Anon., "AMAX: in Perspective; Carteret-Copper, Specialty
Alloys and Precious Metals", Engineering and Mining
Journal (September, 1972).
25. National Air Pollution Control Administration, "Air
Pollution Aspects of Brass and Bronze Smelting and
Refining Industry", U.S. Dept. of Health, Education, and
Welfare (November, 1969).
26. Branner, George C., "Secondary Nonferrous Metals
Industry In California", U.S. Dept. of Interior, Bureau
of Mines Information Circular 8143 (1962) .
27. Dorrielson, J.A. (Ed.), Air Pollution Engineering, 2nd
Edition, Office of Air and Water Programs, Environmental
Protection Agency (1973).
28. "A Study to Identify Opportunities for Increased Solid
Waste Utilization", National Association of Secondary
Materials Industries, Inc., Vcls. II through VII (1972),
PB-212 730.
29. Anon., "Technical Report No. 11 - Secondary Brass or
Bronze Ingot Production Plants" in Background
Information for Proposed New Source Performance
Standards, Vol. I, U.S. Environmental Protection Agency,
Office of Air and Water Programs, Office of Air Quality
Planning and Standards, APTD-1352a, Research Triangle
Park, North Carolina (June, 1973).
30. Peters, M., and Timmerhaus, K., Plant Design and
Economics for Chemical Engineers, McGraw-Hill, New York
(1968) .
31. Dalbke, R.G., and Turk, A.J., "Water Pollution Control
Systems Emphasize Conservation and Reuse", Mining
Engineering, p 88-91 (May, 1968).
32. Dean, J.D., Bosqui, F.L., and Lanowette, K.H., "Removing
Heavy Metals from Waste Water", Env. Sci. Technology, 6,
518-552 (1971).
243
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33. Solubilities of Inorganic and Metalorqanic Compounds,
(Seidell) Links, W.F., (Ed.) 4th Ed. American Chemical
Society, Washington, D.C. (1958).
244
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SECTION XII
GLOSSARY
Act
The Federal Water Pollution Control Act Amendments of 1972.
Alloying
The process of altering the ratio of components in base
metal, such as copper, by the addition or removal of such
components. Brass and bronze are alloys of copper.
Anode
A casting of fire-refined copper of a suitable shape that
fits into an electrolytic cell for further refining. The
positive terminal of an electrolytic cell.
Babbitt
A tin and antimony alloy of copper which is used for lining
bearings.
Baqhouse
An air cleaning system consisting of multiple bag filters.
Best Practicable Control Technology Currently Available
Level of technology applicable to effluent limitations for
industrial discharges to surface waters as defined by
Section 301 (b) (1) (A) of the Act.
Billet
A large casting suitable for fabrication into piping, wire,
or similar products.
Black Copper
The crude product from cupola or blast furnace melting.
Black copper contains many of the impurities present in the
charge (which usually includes residues and slags), and must
undergo further refining.
245
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Blinding of Bags in Baghouses
A restriction of the flow of air through the bag due to any
fine dust, moisture, oil, or other material that fills up in
the pores of the filter bag. P
Blister Copper
The semi-refined copper product of the converting process in
primary copper smelters, which removes sulfur and most other
impurities.
Capital Costs
Financial charges which are computed as cost of capital
times the capital expenditures for pollution control. Cost
°J x,Cuplta^ is based uP°n the average of the separate costs
of debt and equity.
Casting Wheel
A disc-shaped array of molds used to prepare ingots or
anodes from molten metal.
Category and Subcategory
Divisions of a particular industry which possess different
traits that affect waste water treatability and reguire
different effluent limitations.
Cathode
The negatively charged electrode of an electrolytic refining
cell on which copper is deposited during refining.
Cathode Copper
Finished product from the electrolytic refining of copper.
Cement Copper
Copper that has been precipitated out of a solution by
metallic iron scrap.
Charcoal Cover
A method of casting copper ingots which produces a smooth
finish. A layer of fine charcoal is spread over the molten
copper immediately after coating in order to prevent
246
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oxidation of the surface of the ingot. In some operations,
charcoal is placed in the meld prior to casting.
Copper-Rich Slag
Slag recovered from melting furnaces with recoverable free
copper or copper-alloy value.
Cupola Melt
Black copper (see definition above).
Depleted Slag
A slag recovered from furnaces with very little or no free
metal content.
Demineralized Water
Water treated to remove most of the cations {metal ions) and
anions.
Direct Discharge
The discharge of plant waste water streams, either with or
without treatment at the plant, to navigable surface waters
without intermediary treatment at a POTW.
Effluent
The waste water discharged from a point source.
Effluent Limitation
A maximum amount per unit of production (or other unit) of
each specific constituent of the effluent that is subject to
limitations in the discharge from a point source.
Electrolyte
A solution that is an electric conductor in which electric
current is carried by the movement of ions.
Electrolytic Cell
Device for the purification of copper. Copper from impure
copper anodes is electrically plated onto pure copper
cathodes through the electrolyte.
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Electrostatic Precipitator
An air cleaning system in which dust particles are
electrically charged and then collected on plates of the
opposite electrical charge.
Electrowinning
The recovery of copper from a leach solution by
electrolysis. The anode is an insoluble material such as
antimonial lead, the cathode is a thin copper sheet, and the
electrolyte is a copper sulfate solution derived from
solvent extraction or vat leaching. Cathodes from
electrowinning are melted and cast into cnoventional
refinery shapes.
Fire-Refined Copper
Copper metal prepared by a smelting procedure employing
oxidation to remove impurities (converting), followed by
reduction with carbon or green poles (poling).
Flux
A component added to a slag cover on a bath of molten copper
or copper alloy to alter the slag fluidity.
Gangue
A waste rock or slag material remaining after most of the
metal values have been removed.
Incompatible Pollutants
Those pollutants which would cause harm to, adversely affect
the performance of, or be inadequately treated by publicly
owned sewage treatment works.
Indirect Discharge
The discharge of plant waste water streams to a POTW which
in turn discharges the stream (commingled with other
industrial and municipal waste streams) to navigable surface
waters.
Lime, Slaked Lime, Hydrated Lime
Calcined limestone, CaO, or hydrated lime, Ca(OH):2.
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Matte
A crude mixture of sulfides cf copper and other metals,
which is formed when sulfur-containing copper ores or
residues are melted.
Materials produced in manufacturing plants such as
punchings, turnings and borings, defective or surplus goods,
and metallurgical residues, such as slags, skimmings, and
drosses, all of which result directly from manufacturing
operations.
Old Scrap
Scrap which consists of obsolete, worn-out, or damaged
articles such as automobile radiators, pipe, wire, bushings,
bearings, and other materials that have been in consumer
service.
Physical-Chemical Treatment
POTW which use chemical processes, such as lime addition and
settling, rather than biological processes to treat incoming
waste streams. This type of POTW is chosen only when a very
high proportion of the incoming waste stream is industrial
in origin and contains materials which are not ordinarily
susceptible to treatment by biological processes.
Point Source
A single source of water discharged from an individual
plant.
Pollutant Parameter
Constituents of waste water determined to be detrimental and
requiring control.
Pretreatment
Treatment performed on waste waters from any source prior to
introduction to joint treatment in publicly owned treatment
works.
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Publicly Owned Treatment Works (PQTW)
Publicly owned devices and systems used in the storage,
treatment, recycling, and reclamation of municipal sewage or
industrial wastes of a liquid nature, as defined by section
212(2) of the Act, and as used in section 307 (b) of the Act.
Rasorite
A flux used in copper refining which is primarily composed
of borax (Na2B407«10 H2O).
Residues
Slags, drosses, or skimmings that are recovered from metal
operations for metal content.
Rough Brass or Bronze Ingots
Commercial 25-pound ingots cast with no protective cover.
These ingots leave a rough surface caused by gas evolution.
Skimmings
Wastes from melting operations that are removed from the
surface molten metal; the wastes consist of metal that is
contained in oxidized metal.
Slag
A molten mixture of oxides that protects the surface of a
molten bath of copper or copper alloy. After use, the slag
may contain metal, metal oxides, and impurities from the
molten metal.
Smooth Brass and Bronze Ingots
Commercial 25-pound ingots cast with charcoal cover. These
ingots have a smooth surface.
Soda Ash
Sodium carbonate, Na£CO_3.
Solids
Copper or copper alloy scrap metal.
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Standard of Performance
A maximum weight discharged per unit of production for each
constituent that is subject to limitations. The weight is
applicable to new sources as opposed to existing sources,
which are subject to effluent limitations.
Table Classifier
A vibrating, ribbed table designed to separate dense ore or
metals from the lighter constituents. Normally the
classifier is used with a flow of water.
Tuyere
A nozzle through which an air blast is delivered to a cupola
or a blast furnace.
Venturi Air Scrubbers
An air cleaning system consisting of intense water-spray
cleaning of the air at a point where the air goes through a
restriction (venturi) in the duct.
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TABLE 1J0. '
METRIC TABLE
CONVERSION TABLE
MULTIPLY (ENGLISH UNITS) by TO OBTAIN (METRIC UNITS)
ENGLISH UNIT ABBREVIATION CONVERSION ABBREVIATION METRIC UNIT
hectares
cubic meters
kilogram - calories
kilogram calories/kilogram
cubic meters/minute
cubic meters/minute
cubic meters
liters
cubic centimeters
degree Centigrade
meters
liters
liters/second
killowatts
centimeters
atmospheres
kilograms
cubic meters/day
kilometer
atmospheres (absolute)
square meters
square centimeters
metric ton (1000 kilograms)
meter
Actual conversion, not a multiplier
acre
acre - feet
British Thermal
Unit
British Thermal
Unit/pound
cubic feet/minute
cubic feet/second
cubic feet
cubic feet
cubic inches
degree Fahrenheit
feet
gallon
gal Ion/minute
horsepower
inches
inches of mercury
pounds
million gallons/day
mile
pound/square
inch (gauge)
square feet
square inches
ton (short)
yard
ac
ac ft
BTU
BTU/lb
cfm
cfs
cu ft
cu ft
cu in
°F
ft
gal
gpm
hp
in
in Hg
Ib
mgd
mi
psig
sq ft
sq in
ton
yd
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
ha
cu m
kg cal
kg cal/kg
cu m/min
cu m/min
cu m
1
cu cm
°C
m
1
I/sec
kw
cm
atm
kg
cu m/day
km
atm
sq m
sq cm
kkg
m
252
* U S. GOVERNMENT PRINTING OFFICE • 1977 228-922/6142
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