S-EPA
United States
Environmental Protection
Agency
Risk Reduction
Engineering Laboratory
Cincinnati, OH 45268
Research and Development
EPA/600/S-92/049 October 1992
ENVIRONMENTAL
RESEARCH BRIEF
Waste Reduction Activities and Options for a
Manufacturer of Electroplated Wire
Alan Ulbrecht and Daniel J. Watts*
Abstract
The U.S. Environmental Protection Agency (EPA) funded a
project with the New Jersey Department of Environmental
Protection and Energy (NJDEPE) to assist in conducting waste
minimization assessments at 30 small- to medium-sized busi-
nesses in the state of New Jersey. One of the sites selected
was a facility that manufactures electroplated wire for use in
the automotive, computer, aerospace, and related industries.
The wire is plated with copper, silver, nickel, tin, or tin-lead
according to customer specifications. The process involves
cleaning of the base wire followed by electroplating using a
reel-to-reel technique. A site visit was made in 1990 during
which several opportunities for waste minimization were ider$r
fied. Options identified included reduction of discharge volume,
improved rinsing operations, changes in the wire drawing op-
eration, and consideration of a zero-discharge system. Imple-
mentation of the identified waste minimization opportunities
was not part of the program. Percent waste reduction, net
annual savings, implementation costs and payback periods
were estimated.
This Research Brief was developed by the Principal Investiga-
tors and EPA's Risk Reduction Engineering Laboratory in Cin-
cinnati, OH, to announce key findings of this completed as-
sessment.
Introduction
The environmental issues facing industry today have expanded
considerably beyond traditional concerns. Wastewater, air
emissions, potential soil and groundwater contamination, solid
waste disposal, and employee health and safety have become
increasingly important concerns. The management and dis-
* New Jersey Institute of Technology, Newark, NJ 07102
posal of hazardous substances, including both process-related
wastes and residues from waste treatment, receive significant
attention because of regulation and economics.
As environmental issues have become more complex, the
strategies for waste management and control have become
more systematic and integrated. The positive role of waste
minimization and pollution prevention within industrial operations
at each stage of product life is recognized throughout the
world. An ideal goal is to manufacture products while generat-
ing the least amount of waste possible.
The Hazardous Waste Advisement Program (HWAP) of the
Division of Hazardous Waste Management, NJDEPE, is pursu-
ing the goals of waste minimization awareness and program
implementation in the state. HWAP, with the help of an EPA
grant from the Risk Reduction Engineering Laboratory, con-
ducted an Assessment of Reduction and Recycling Opportuni-
ties for Hazardous Waste (ARROW) project. ARROW was
designed to assess waste minimization potential across a
broad range of New Jersey industries. The project targeted 30
sites to perform waste minimization assessments following the
approach outlined in EPA's Waste Minimization Opportunity
Assessment Manual (EPA/625/7-88/003). Under contract to
NJDEPE, the Hazardous Substance Management Research
Center at the New Jersey Institute of Technology (NJIT) as-
sisted in conducting the assessments. This research brief
presents an assessment of the manufacturing of electroplated
wire (1 of the 30 assessments performed) and provides recom-
mendations for waste minimization options resulting from the
assessment.
Methodology of Assessments
The assessment process was coordinated by a team of techni-
cal staff from NJIT with experience in process operations,
Printed on Recycled Paper
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basic chemistry, and environmental concerns and needs. Be-
cause the EPA waste minimization manual is designed to be
primarily applied by the in-house staff of the facility, the degree
of involvement of the NJIT team varied according to the ease
with which the facility staff could apply the manual. In some
cases, NJITs role was to provide advice. In others, NJIT
conducted essentially the entire evaluation.
The goal of the project was to encourage participation in the
assessment process by management and staff at the facility.
To do this, the participants were encouraged to proceed through
the organizational steps outlined in the manual. These steps
can be summarized as follows:
• Obtaining corporate commitment to a waste minimization
initiative
• Organizing a task force or similar group to carry out the
assessment
• Developing a policy statement regarding waste minimiza-
tion for issuance by corporate management
• Establishing tentative waste reduction goals to be achieved
by the program
• Identifying waste-generating sites and processes
• Conducting a detailed site inspection
• Developing a list of options which may lead to the waste
reduction goal
• Formally analyzing the feasibility of the various options
• Measuring the effectiveness of the options and continuing
the assessment.
Not every facility was able to follow these steps as presented.
In each case, however, the identification of waste-generating
sites and processes, detailed site inspections, and development
of options was carried out. Frequently, it was necessary for a
high degree of involvement by NJIT to accomplish these steps.
Two common reasons for needing outside participation were a
shortage of technical staff within the company and a need to
develop an agenda for technical action before corporate com-
mitment and policy statements could be obtained.
H was not a goal of the ARROW project to participate in the
feasibility analysis or implementation steps. However, NJIT
offered to provide advice for feasibility analysis if requested.
In each case, the NJIT team made several site visits to the
facility. Initially, visits were made to explain the EPA manual
and to encourage the facility through the organizational stages.
If delays and complications developed, the team offered assis-
tance in the technical review, inspections, and option develop-
ment.
No sampling or laboratory analysis was undertaken as part of
these assessments.
Facility Background
The facility is a manufacturer of electroplated wire, used typically
for electrical wiring applications in the automotive, computer,
aerospace, and related industries. The process involves clean-
ing of the base wire and plating with copper, silver, nickel, tin,
or tin-lead as required by the customer specification. The
plated wire is drawn to assure the correct diameter.
The facility is located in an urban area and employs about 25
people. This particular facility has been in operation for many
years and the manufacturing practices are well ingrained in the
staff. A metal recovery system has been installed to limit the
level of metals in the discharge to the sewerage system.
Manufacturing Processes
The production of the plated wire is fundamentally a 3-step
operation—cleaning the base wire, plating the desired top coat,
and drawing to assure the required size in the final product.
Each of these steps has a number of individual operations,
however. The base wire which is usually copper of beryllium/
copper is electro-cleaned in a caustic solution, rinsed in water,
acid dipped, and water rinsed. The cleaned wire is then plated
in a reel-to-reel operation with copper, silver, nickel, tin, or tin-
lead as required by the customer. There is a final rinse after
the plating bath. The plated wire is size-reduced by drawing
through a diamond die using a lubricant of water and detergent.
Existing Waste Management Activities
The company has already instituted a program of pollution
prevention. This is perhaps best illustrated by the ion exchange/
electrowinning procedures which have been installed to recover
metals from the combined dragout and rinse waters before
they are sent to the POTW for treatment.
In schematic terms all of the rinses and acid/base cleaning
effluents are combined and prepared for the ion exchange/
electrowinning process. The exception to this is an intermediate
processing step required for the effluent from the copper and
silver plating baths and rinses. These effluents contain cyanide
and require a cyanide destruction step. This is accomplished
by oxidation with hydrogen peroxide.
The combined effluents are adjusted to near neutral pH and
filtered to remove any solids or dirt. The filtered solutions are
piped to a multi-bed ion exchange system to remove copper
and other residual metals. The exchanged aqueous stream is
sent to the POTW for treatment. It is reported that this stream
is approximately 500 gal/day.
When the resin is spent, or has reached its exchange capacity,
it is regenerated with sulfuric acid and backwashed. The back-
wash averages about 300 gal and is rich in copper and other
metals. The regeneration is required about once a month. The
backwash is pumped to a 500-gal electro-winning tank where
the metal is plated onto cathodes until the concentration of
metal in solution drops below 50 ppm. The residual solution is
looped back to the ion exchange system for further treatment
and the plated out material is sold for scrap.
The lubricating process for the wire drawing step is basically a
closed loop system. When the water-detergent bath appears to
be too dirty, it is decanted off and disposed of as hazardous
waste. The volume of this material appears to be about 25 gal
and is disposed of about every 2 weeks.
Waste Minimization Opportunities
The type of waste currently generated by the facility, the
source of the waste, the quantity of the waste and the annual
treatment and disposal costs are given in Table 1. This particular
facility presents a dilemma in describing waste streams. The
presence of an in-place material recovery system means that
the actual waste streams sent offsite are relatively insignificant
in terms of the total effluent from the process before the
material recovery step. Therefore, some options will also be
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presented which may relate to improvement of the recovery
procedure.
Table 2 shows the opportunities for waste minimization recom-
mended for the facility. The type of waste, the minimization
opportunity, the possible waste reduction and associated sav-
ings, and the implementation cost along with the payback time
are given in the table. The quantities of waste currently gener-
ated at the facility and possible waste reduction depend on the
level of activity of the facility. All values should be considered
in that context.
It should be noted that the economic savings of the minimization
opportunity, in most cases, results from the need for less raw
material and from reduced present and future costs associated
with waste treatment and disposal. It should also be noted that
the savings given for each opportunity reflect the savings
achievable when implementing each waste minimization op-
portunity independently and do not reflect duplication of savings
that would result when the opportunities are implemented in a
package.
The cost savings are calculated both in terms of avoided costs
of waste disposal and recovery of the value of raw material
V Mention of trade names or commercial products does not constitute endorsement
or recommendation for use.
used again. Also, no equipment depreciation is factored into
the calculations.
Regulatory Implications
There do not seem to be significant regulatory implications of
pollution prevention initiatives at this facility. It is likely that the
metal recovery system was installed at the facility in light of
regulatory pressures to control the level of metals in the effluent
sent to the POTW. It is also likely, according to the POTW, that
additional restrictions will be applied to such effluents in the
future. In such a case, the facility will have to enhance its
testing of effluent in order to assure that all emissions meet the
more severe requirements. The concept of zero discharge to
the POTW may also be a viable strategy for the facility, although
retaining the metal recovery capability would be desirable.
This Research Brief summarizes a part of the work done under
cooperative Agreement No. CR-815165 by the New Jersey
Institute of Technology under the sponsorship of the New
Jersey Department of Environmental Protection and Energy
and the U.S. Environmental Protection Agency. The EPA Project
Officer was Mary Ann Curran. She can be reached at:
Pollution Prevention Research Branch
Risk Reduction Engineering Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
Table 1. Summary of Current Waste Generation
Waste Generated
Source of Waste
Annual Quantity
Generated
Aqueous Discharge to
Sewer
Detergent/Water Mixture
Metal-Containing Aqueous
Waste Stream
Effluent from the ion exchange
system
Lubricant from the wire
drawing operation
Combined rinses and cleaning
effluents
182,000 gal
650 gal
182,000 gal
Annual Waste
Management Costs
$48
1200
The facility could not provide the
costs of this part of their operation.
This is the feed stock for the metal
recovery operation and the key cost
factors include periodic replacement
of resin,acid costs for regeneration
of the resin, power consumption for
electrowinning, and loss of metals
from the plating baths. There is some
cost recovery from sale of recovered
metal scrap. Estimate: $6,000
•frv.8. GOVERNMENT PRINTING OFFICE: I9M - SSO-M7/MMO
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Table 2. Summary of Recommended Waste Minimization Opportunities
Minimization Opportunity Annual Waste Reduction
Waste Stream
Reduced
Quantity
Percent
Net Implementation Payback
Annual Savings Cost Years*
Wire Drawing Lubricant
Metal-Containing
Aqueous Waste Stream
Filtration or centrifugation 325 gal
to remove dirt and solids
and extend life of fluid.
Additions ofbiocide may extend
fluid life even further.
Because this is a mechanical 650 gal
operation, filtration to remove
any metal particles should produce
a liquid which is not hazardous.
This should be confirmed by appropriate
testing. Disposal as non-hazardous
water solution would significantly
lower disposal costs.
Install solenoid valves to shut 9,100 gal
off rinse water flow when plating
current is off. This reduces flow
through the system and saves on water
consumption.
50
100
$600
1200
$1,000
1,200
1.6
1.0
100
primarily
from water
savings but
but also reduces
cation load on
resin, extending
time between
resin regenerations
300
3.0
Install scrapers and wipers to
remove adhering dragout from the
wire and return to the plating
baths. Because of the uniformity
of the wire shape as contrasted
to plating of irregularly shaped
articles, this is a technically
feasible step. This returns plating
chemicals to use and reduces load
on the metal recovery system.
Use rinse water as make-up water
for plating baths.
1,820 gal
(The volume of the
stream would be rela-
tively unchanged,
however the metal
content would be
substantially reduced.)
9,100 gal 5
(The volume which can
easily be added back
depends on the rate of
removal or evaporation
from the plating baths.
The savings could be greater
than estimated here.)
3000
1000
0.3
300
100
0.3
* Savings result from reduced raw material and treatment and disposal costs when implementing each minimization opportunity independently.
United States
Environmental Protection Agency
Center for Environmental Research Information
Cincinnati, OH 45268
Official Business
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EPA/600/S-92/049
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