United States
 Environmental Protection
 Agency
National Risk Management
Research Laboratory
Cincinnati, OH 45268
 Research and Development
EPA/600/SR-97/032
                     March 1997
 Project Summary
 Evaluation of Alternatives  to
 Chlorinated  Solvents  for Metal
 Cleaning
 Karen B. Thomas and Michael Eljenbecker
  The  Massachusetts Toxics Use Re-
duction Institute (TURI) was funded by
the Environmental  Protection Agency
to perform research to support the
EPA's  33/50 Program, a voluntary pol-
lution  prevention program to reduce
national releases and offsite transfers
of 17  toxic chemicals.  The research
project Investigated alternatives to chlo-
rinated  solvents  used for  metal
degreasing at three companies. Trie re-
sults reported for one company docu-
ment a situation where the conversion
to an  aqueous cleaning system  had
already been implemented. Those for a
second company provide real-time in-
formation about the conversion from
an intermediate solvent to an aqueous
system. Results for the third company
contribute information about alterna-
tives that must be applicable to a vari-
ety of  substrates and configurations.
Testing of the alternatives was con-
ducted both at the  companies and at
the TURI's Surface Cleaning Labora-
tory located at the University of Massa-
chusetts  Lowell, Lowell, MA. In addi-
tion to the technical evaluations, the
project evaluated financial and envi-
ronmental impacts  of the alternative
systems;. For the financial analyses, the
Total Cost Assessment methodology
includes many important environmen-
tal costs not typically included in  a
financial analysis. A substitution analy-
sis methodology that provides qualita-
tive results was developed and used to
evaluate  the environmental, occupa-
tional, and public health effects of the
alternative cleaning processes.
  This  Project Summary was developed
by the  National Risk Management Re-
search  Laboratory,  Cincinnati, OH, to
announce key findings of the research
project that is  fully documented in a
 separate report of the same title (see
 Project Report ordering information at
 back.)

 Introduction
  Cleaning and degreasing of metal parts
 in the metal finishing and metal working
 industries have traditionally been accom-
 plished by the use of chlorinated solvents
 in vapor  degreasers or immersion sys-
 tems.  In this context,  cleaning and
 degreasing is,  simply, the  removal of con-
 tamination from the metal surface. This
 function is necessary for  successful part
 performance  in subsequent operations
 (e.g., plating or welding)  or is desirable
 aesthetically.  The  chlorinated solvents
 most commonly used for metal cleaning
 include: 1,1,1-trichloroethane (1.1,1-TCA),
 trichloroethylene (TCE), perchloroethylene
 (PERC), dichloromethane (methylene chlo-
 ride or METH), and chlorofluorocarbons.
 Chlorinated solvents are effective clean-
 ers and, in the past, have been consid-
 ered "safe" to  workers because they are
 nonflammable.
  Due to  concern over the ozone layer,
 photochemical smog, and worker health,
 increasingly  strict  environmental regula-
 tions have been promulgated on the use
 of chlorinated  solvents. The result has
 been higher costs associated with the pur-
 chase and disposal of chlorinated solvents.
 Traditional chlorinated solvent cleaning is
 becoming  a process of the past. For many
 companies, however,  changing  from a
 proven process to a new technology is a
 difficult task. Many alternatives presented
 as "perfect" solutions are found to be inef-
 fective  cleaners, too  expensive, or  to
 present safety  hazards. A careful evalua-
tion of the options can help in selecting
the most cost effective and technically fea-
sible solution without compromising worker
 health and safety  or environmental pro-
tection.
                                                   Printed on Recycled Paper

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the new process and necessitate  further
evaluation following  installation. An  eco-
nomic evaluation of  a technically proven
chemical or process  provides valuable in-
formation affecting the decision to imple-
ment or not.  The results of the financial
assessment further inform the decision to
adopt or not. However, technical and  fi-
nancial  information  combined is not the
final word  in  decision  making. Further
evaluation is required to assess the envi-
ronmental,  health, and safety issues in-
volved with the chemicals and processes.
While the technical and cost assessments
are not simple, the environmental, health,
and safety  assessment, called  substitu-
tion analysis, is perhaps the most difficult
because there is no generally agreed-on
and reliable method for evaluating the en-
vironmental and worker health and safety
risk of alternatives.
  In using the three evaluative steps de-
scribed above, it is important to remem-
ber that each project and facility may have
different  priorities for  making  decisions
about  whether to implement a particular
technology. This was clearly demonstrated
in this project as the participating compa-
nies had different motives for seeking sub-
stitute technologies. This in turn, dictated
which evaluative step was most  important
to them  and indicates that the results of
any  one of the three can  be the driving
factor in  a decision. Despite the emphasis
placed on one evaluative step on a given
project, all three  aspects must be evalu-
ated so  that valuable pieces of informa-
tion are not ignored.
  The full  report  was submitted in fulfill-
ment of  Contract No. CR821859-01-0 by
the Massachusetts Toxics Use Reduction
Institute under the sponsorship of the U.S.
Environmental Protection Agency.
                                                                    •&U.S. GOVERNMENT PRINTING OFFICE: 1997 - 549-001/60136

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  Approach

  Technical Analysis
    During the technical analysis phase, al-
  ternatives to the chlorinated solvents were
  identified, demonstrated, and evaluated.
  The three companies that participated  in
  this project were Parker Hannifin Corpo-
  ration, Market Forge, and Company A, an
  electroplating facility. At its Waltham, MA
  facility,  Parker Hannifin manufactures
  pumps for aircraft engines under primary
  SIC code 3724.  In  1992,  the company
  began to investigate the replacement  of
  its two vapor degreasers with an  aqueous
  cleaning system. The original idea was  to
  replace both vapor degreasers with  one
  immersion cleaning system that could sat-
  isfy the highest cleanliness  needs. After
  careful  consideration  of cleaning  needs
  and logistics, the company decided to re-
  place  the vapor degreasers  with three
  pressure spray washers for frequent re-
  mote cleaning  following machining,  one
  ultrasonic unit for the  highest cleanliness
  needs and one immersion tank for  clean-
  ing  following  heat  treatment. Parker
  Hannifin was chosen to document a situa-
  tion where the conversion  to aqueous
  cleaning had already  been made and to
  evaluate the new system for its  health
  and safety,  environmental,  and  financial
  performance. A technical evaluation was
- performed~at -TURI's-Surf ace-Gleaning
  Laboratory in order to make improvements
  to Parker Hannifin's current aqueous clean-
  ing process.
    Located in Everett,  MA, Market  Forge
  manufactures cooking steamers. Prior to
  August 1993, Market Forge used a 1,1,1-
  TCA vapor degreasing system to degrease
  carbon steel  and  aluminum boiler parts
  before welding. The performance of TCA
  was satisfactory, but  its use was discon-
 tinued  because of the  labeling  require-
  ments  of the Montreal Protocol. On  the
  advice of their supplier, Market Forge
  switched from TCA to an aliphatic petro-
  leum distillate solvent  (CAS 64742-88-7).
 As soon as the switch was made,  the
 welders of both the carbon steel and alu-
 minum parts  began to experience  prob-
 lems. Market Forge was chosen as a com-
 pany  in the difficult  transition stage. A
 technical evaluation  was performed at
 TURI's Surface Cleaning Laboratory to find
 a suitable cleaning process and chemistry
 to replace the petroleum distillate. Based
 on  the  information obtained  from this
 project, Market Forge purchased an Ameri-
 can Metal Wash pressure spray washer.
 The unit was recently installed and is op-
 erating effectively.
    Company A is a job-shop electroplating
  company  located in Massachusetts, By
  the nature of the job-shop business, Com-
  pany A cannot always predict what types
  of metals it will have to  clean and thus
  requires  a flexible cleaning  system/ ca-
  pable of  cleaning  many different  sub-
  strates. Currently the company cleans all
  parts  in  a vapor degreaser using TCE.
  Company A was chosen because its situ-
  ation  is one  shared by  many job-shop
  platers in the northeast,  namely, a  wide
  variety of substrates and contaminants. A
  technical assessment identified the follow-
  ing alternatives for  further study: media
  blasting using sodium bicarbonate, plastic
  or carbon  dioxide,  ultrasonic aqueous,
  "closed" vapor degreasing, upgrading of
  the existing vapor degreaser, Advanced
  Vapor Degreasing (AVD™) system, and
  supercritical carbon dioxide.

  Financial Analysis
    For the financial analysis, a total cost.
  assessment methodology was used to per-
  form financial analyses of the alternative
  cleaning  processes. Traditional financial
  analysis often includes only the costs di-
  rectly associated with production, such as
  labor and capital and does not include the
  costs  (and  savings) that  make pollution
  prevention projects  profitable. The Total
  Cost  Assessment methodology  used in
=this project is an innovative evaluative tool
  that examines many  other  important costs
  associated with an  investment including
  staff  time for  environmental reporting,
  waste  management costs, and permitting
  fees.

  Substitution Analysis
    A substitution analysis methodology was
  developed and used  to evaluate the envi-
  ronmental, occupational, and public health
  effects of  the  alternative cleaning  pro-
  cesses. The substitution analysis described
  is qualitative in nature. It allows the com-
  parison of alternatives using  many crite-
  ria, but a final  decision as to the best
  alternative must be made  by the  investi-
  gator. Described in worksheet format, this
  approach highlights both the areas of con-
  cern for alternative processes and areas
  where  those substitutes clearly are supe-
  rior to the current process.  The worksheet
  will aid the decision  maker in making1 in-
 formed decisions without overlooking .im-
  portant issues.

  Conclusions
   Some general conclusions were drawn
 from the technical evaluation phase in. re-
 gard to chemical compatibility/process
 specification and  "drop-in" replacements.
  For chemical compatibility/process speci-
  fication, it was concluded that rinsing of a
  non-silicated cleaner is not always neces-
  sary even  when a painting operation fol-
  lows,  and  aqueous immersion  cleaning
  can be a viable option for steel and alumi-
  num substrates prior to nitriding or follow-
  ing  heat treat operations. With regard to
  "drop-in" replacements,  it was concluded
  that a thorough technical evaluation of so-
  called  "drop-in" replacements is neces-
  sary to avoid  unforeseen costs  and that
  job shops present an unmet challenge to
  the vendors of "drop-in" replacements.
    Some  general conclusions were made
  following the financial analysis phase: 1) if
  the aqueous systems are replacing  older
  solvent-based equipment, a savings in
  electricity costs  may be  realized, espe-
  cially if air drying is not required; 2) de-
  pending  on the cooling capacity of the
  vapor  degreaser, the aqueous  systems
  may actually use less water; 3) the profit-
  ability of an investment in aqueous clean-
  ing equipment can  be improved  by  pur-
  chasing based on cleaning needs at dif-
  ferent  stages in the production  process;
  4) the aggressive taxes  on CFCs  and
  TCA have made aqueous alternatives fea-
  sible economically; and 5) the Total Cost
  Assessment methodology  (P2/Finance
  Software) can be used in an iterative pro-
  cess to determine costs for unknowns by
-requiring -a - certain  net present value;™
  These  costs can then  be assessed to
 determine if, for example, a regulatory re-
 quirement could be met for a certain cost
  rather than  actually attempting to place a
 value on  meeting the regulatory require-
  ment.
   This project studied three  principal
 evaluation steps that inform the decision-
 making .process for chemical or  process
 substitution: technical evaluation, economic
 evaluation, and environmental, health and
 safety evaluation. Each evaluation step is
 important in determining the viability of a
 substitute technology, in comparison to
 the existing technology as well as to other
 competing  substitute  technologies.  The
 steps can be performed in any order and
 their relative importance can vary from
 project  to project. The technical evalua-
 tion of a replacement process for an exist-
 ing technically successful process is often
 the most  important evaluative step.  The
 success or failure of the technical evalua-
 tion determines whether or not the  pro-
 cess will be evaluated further. Complete
 technical evaluation at the lab- and pilot-
 scale levels can lead to a  smooth transi-
 tion into the  new process.  An incomplete
 technical  evaluation can lead to unfore-
 seen problems with the  incorporation of

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 Karen B. Thomas and Michael Ellenbecker are with the Toxics Use Reduction
   Institute, University of Massachusetts Lowell, Low&ll, MA 01854.
 Paul Randall is the EPA Project Officer (see below).
 The complete report, entitled "Evaluation of Alternatives to Chlorinated Solvents for
   Metal Cleaning," (OrderNo. PB97-147946, Cost: $28.00, subject to change) will
 \  be available only from:
         National Technical Information Service
         5285 Port Royal Road
         Springfield, VA 22161
         Telephone: 703-487-4650
 The EPA Project Officer can be contacted at:
         National Risk Management Research Laboratory
         U.S. Environmental Protection Agency
         Cincinnati, OH 45268
    \
United States
Environmental Protection Agency
Center for Environmental Research Information
Cincinnati, OH 45268
Official Business
Penalty for Private Use $300
      BULK RATE
POSTAGE & FEES PAID
         EPA
   PERMIT NO. G-35
EPA/600/SR-97/032

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