SEPA
United States
Environmental Protection
Agency
Research and Development
Risk Reduction
Engineering Laboratory
Cincinnati, OH 45268
EPA/600/S-92/042 Oct. 1992
ENVIRONMENTAL
RESEARCH BRIEF
Waste Reduction Activities and Options for a
Manufacturer of Room Air Conditioning Units and Humidifiers
Hana Saqa 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 room air conditioners and
humidifiers. A site visit was made in 1990 during which several
opportunities for waste minimization were identified. These
opportunities include more efficient recovery of degreasing
solvents, movement to aqueous degreasing procedures, and
segregation and reuse of hydraulic and lubricating fluids.
Implementation of the identified waste minimization opportuni-
ties 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 disposal
of hazardous substances, including both process-related wastes
and residues from waste treatment, receive significant attention
because of regulation and economics.
* New Jersey Institute of Technology, Newark, NJ 07102
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) assisted
in conducting the assessments. This research brief presents
an assessment of a room air conditioner and humidifier manu-
facturer (1 of the 30 assessments performed) and provides
recommendations 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,
basic chemistry, and environmental concerns and needs. Be-
cause the EPA waste minimization manual is designed to be
primarily applied by the inhouse staff of the facility, the degree
Printed on Recycled Paper
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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.
It 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.
The Paint Manufacturer
The facility is a producer of paints, used primarily in the metal
finishing industry including automobile refinishing applications.
This business requires production of a large variety of colors
and finish types, most in relatively small quantities. The specifi-
cations of their customers allow a very narrow range of variation
in color and appearance of the finished product. This severely
limits the flexibility the company has in changing production
processes.
The production of the various types of paints is conceptually
very simple. Required operations include mixing and blending
(under carefully specified conditions) raw materials either pur-
chased from vendors or shipped from other company sites. No
manufacturing of paint constituents takes place at this facility.
After formulation and blending, the paints are transferred to a
variety of containers for shipment to the customer. The pro-
cessing equipment is cleaned prior to preparation of the next
batch. The cleaning operation typically includes multiple rinses
with solvent in order to remove the pigments and additives
remaining from the previous batch.
Paint production uses a solvent or liquid carrier to dissolve or
suspend the components of the coating system. This process
is a large user of solvents. At present, the preponderance of
the solvents used in these applications are organic. However,
there is a trend In the coatings industry toward water-based
products where customer demands and product performance
criteria are met. The technology for water-based coatings has
not been sufficiently advanced to address all such demands
and performance requirements. Therefore, solvent-based paints
and coatings will be required for some time.
The company has already instituted a program of pollution
prevention. This is perhaps best illustrated by the acquisition
and use of a large capacity still which allows recovery and
reuse of the solvents from the equipment washing operations.
Other pollution prevention efforts have been carried out in
conjunction with the corporate research and development group.
This lead to the reduction or elimination of the use of heavy
metal-containing dyes and pigments in products produced by
this facility.
Waste Streams and Existing Waste
Management
This particular facility presents a challenge in describing waste
streams. The presence of an operating solvent recovery sys-
tem means that the actual waste streams sent offsite are
relatively insignificant in terms of the total effluent from the
process before the solvent distillation. Moreover, where there
is a significant level of air emissions to be addressed, the
meaning of the term "treatment and disposal costs" has to be
strained to include simple loss of the value of materials.
The major RCRA waste from this facility is the still bottoms
from the recovery/recycling/reuse of waste solvents from the
equipment washing process. About 250 drums of this material
are produced annually from the facility and are sent offsite for
disposal. This quantity represents 10% to 20 % of the volume
of waste solvents which were sent for disposal prior to the
installation of the distillation equipment.
Another waste stream results from quality control samples of
finished batches which are retained at the facility for a period of
time for examination if customer problems or complaints come
in about specific batches of paint. After the retention period,
the samples are discarded as hazardous waste. Approximately
one quart size samples are collected and retained. The typical
current practice is to recover the solvent from these retained
samples through the solvent recovery system. There was no
information available on the number of these samples gener-
ated and retained each year.
Another waste stream identified was a waste oil stream from
equipment maintenance and repair. This stream averages 3 to
4 drums per year and is sent offsite for recycling and recovery.
The greatest pollution prevention challenge at this facility is not
RCRA-type waste streams. Rather it consists of stack emis-
sions and fugitive air emissions. SARA Title III reporting and
additional estimates indicated that approximately 200,000 Ib of
solvent are emitted to the atmosphere annually. The facility
intends to address this situation using a pollution prevention
approach.
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on the level of activity of the facility. All values should be
considered in that context.
H should be noted that the economic savings of the minimiza-
tion opportunity, in most cases, results from the need for less
raw material and from reduced present and future costs asso-
ciated 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
opportunity independently and do not reflect duplication of
savings that would result when the opportunities are imple-
mented in a package. Also, no equipment depreciation is
factored into the calculations.
The most beneficial option from the perspective of risk reduc-
tion would be acceleration of the program to replace the final
vapor decreasing unit with another aqueous based cleaner. It
is recognized that there are some concerns about the space
available for such a substitute unit, as well as some concerns
about the effect of the change on rate of production at the
facility. It should be recognized that the vapor degreasing unit
is being used because it is effective and rapid as a cleaner.
Substitute units often are somewhat less efficient meaning that
throughput may be reduced. This is sometimes a significant
manufacturing concern. It is suggested that a manufacturing
time/motion/layout study be carried out to address some of
these concerns.
In the meantime, while the solvent vapor degreaser is still in
operation, it is likely that a portion of the fugitive emissions
result from the following: less than optimum cooling/condensa-
tion of the vapor, the ventilation capture velocity may not be
functioning adequately, or the water/trichloroethylene separator
may not be operating as effectively as it should. Attention to
these operational parameters may impact the amount of loss of
the solvent.
At present the leaked hydraulic oil is mixed with the other
machining and lubricating waste oils and hauled away as
hazardous waste. Capture of the leaked hydraulic oil is sug-
gested. The material may be acceptable for reuse if it is not
allowed to become contaminated with other materials. If not
reusable immediately, it may be possible to recondition it either
mechanically onsite or by use of a commercial reconditioning
service.
It is possible that some of the oil/grease from the coil cleaning
operation in alkaline aqueous media is not completely separated
by the oil separator due to the formation of oil in water emulsions.
It is suggested that polymeric emulsion breakers be tried in
order to improve the performance of this unit. It should be
realized that this option would not be expected to result in any
savings for the facility. Rather it would result, if effective, in a
cleaner aqueous stream.
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
Waste Oils
Wastewater
Source of Waste
Mixed hydraulic, lubricating
Discharged water from aaueous
Chlorinated Solvent/
Sludge
Spent Activated Carbon
Solvent Loss
degreasers
Spent solvent from degreasers
Filters from vapor degreaser
Fugitive emissions from degreaser
Annual Quantity
Generated
40,000 gal
200,000 gal
27,000 Ib
120lb
>2,000 Ib
Annual
Costs
$80,000
$82
$12,800
$350
>$1,300
•&U.S. GOVERNMENT PRINTING OFFICE: 1994 - S50-067/MI63
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Table 2. Summary of Waste Minimization Opportunities
Minimization Opportunity
Waste Stream
Reduced
Annual Waste Reduction Net Implementation Payback
Quantity Percent Annual Savings Cost Years*
Waste Oils
Chlorinated Solvent/
Sludge, Spent Activa-
ted Carbon, Solvent
Loss
Solvent Loss
Collect and segregate hydraulic
oil leaks, check quality,
if acceptable, reuse, or purify
by filtration, centrifugation,
or use of outside, reconditioning
service
Complete change to aqueous alkaline
degreasing operation.
5000 gal
12%
30,000 Ib
100%
Improve mechanical performance of
the solvent capture system
600 Ib
30%
$ 12,500
$4,000
0.3
$14,050
$30,000
2.0
(It must be realized that this option will
increase the quantity of water sent to the
POTWand will increase the amount of waste
oil recovered from the oil separator.)
$400 $500 1.2
(This represents regular maintenance
which will be incurred annually,
therefore, any payback period based
on implementation costs, may be illusory.)
" Savings result from reduced raw materials 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
Penalty for Private Use
$300
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EPA/600/S-92/042
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