$.;_•*
Evaluation of Alternatives to Chlorinated
Solvents for Metal Cleaning
by
Karen B. Thomas
Michael Ellenbecker
Toxics Use Reduction Institute
University of Massachusetts Lowell
Lowell, Massachusetts 01854
CR821859-01-0
Project Officer
Paul Randall
Sustainable Technology Division
National Risk Management Research Laboratory
Cincinnati, Ohio 45268
NATIONAL RISK MANAGEMENT RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
-------
«
-------
Notice
The U.S. Environmental Protection Agency through its Office of Research and Development partially funded
and collaborated in the research described here under Cooperative Agreement CR821859-01-0 to the
University of Massachusetts Lowell's Toxics Use Reduction Institute. It has been subjected to the Agency's
peer and administrative review, and has been approved for publication as an EPA document. Mention of
trade names or commercial products does not constitute endorsement or recommendation for use.
11
-------
-------
Foreword
The U.S. Environmental Protection Agency is charged by Congress with protecting the Nation's land, air, and
water resources. Under a mandate of national environmental laws, the Agency strives to formulate and
implement actions leading to a compatible balance between human activities and the ability of natural
systems to support and nurture life. To meet this mandate, EPA's research program is providing data and
technical support for solving environmental problems today and building a science knowledge base necessary
to manage our ecological resources wisely, understand how pollutants affect our health, and prevent or reduce
environmental risks in the future.
The National Risk Management Research Laboratory is the Agency's center for investigation of
technological and management approaches for reducing risk from threats to human health and the
environment. The focus of the Laboratory's research program is on methods for prevention and control of
pollution to air, land, water and subsurface resources; protection of water quality in public water systems;
remediation of contaminated sites and ground water; and prevention and control of indoor air pollution. The
goal of this research effort is to catalyze development and implementation of innovative, cost-effective
environmental technologies; develop scientific and engineering information needed by EPA to support
regulatory and policy decisions; and provide technical support and information transfer to ensure effective
implementation of environmental regulations and strategies.
This publication has been produced as part of the Laboratory's strategic long-term research plan. It is
published and made available by EPA's Office of Research and Development to assist the user community
and to link researchers with their clients.
E. Timothy Oppelt, Director
National Risk Management Research Laboratory
ill
-------
-------
Abstract
This project report details results of investigations into alternatives to chlorinated solvents used for metal
degreasing. Three companies participated in this project. The results reported for one company document a
situation where the conversion to an aqueous cleaning system had already been implemented. Those for a
second company provide real-time information about the conversion from an intermediate solvent to an
aqueous system. Finally, results for the third company contribute information about alternatives that must be
applicable to a variety of substrates and configurations. Testing of the alternatives was conducted both at the
companies and at the Toxics Use Reduction Institute's Surface Cleaning Laboratory located at the University
of Massachusetts at Lowell, hi addition to the technical evaluations, the project report provides financial
analyses and environmental impact assessments on the cleaning alternatives. For the financial analyses, ithe
Total Cost Assessment methodology was used which includes many important environmental costs not
typically included in a financial analysis. A substitution analysis methodology that provides qualitative
resulte was developed and used to evaluate the environmental, occupational and public health effects of the
alternative cleaning processes.
This report was submitted in fulfillment of Cooperative Agreement No. CR821859-01-0 by the
Massachusetts Toxics Use Reduction Institute. This report covers a period of time from October 1993 to
October 1995.
IV
-------
-------
Table of Contents
Foreword iii
Abstract iv
List of Tables viii
List of Figures ix
Acronyms and Abbreviations . x
Acknowledgments xi
Executive Summary xii
Chapter 1 Introduction 1
Introduction 1
EPA's 33/50 Program 1
Overview of the Clean Alternatives Project 2
Chapter 2 Methods and Materials for Surface Cleaning 3
Vapor Degreasing 3
Solvents Used in Vapor Degreasing 4
Trichloroethylene 4
1,1,1-Trichloroethane 5
Methylene Chloride 5
CFC-113 : 6
Alternative Cleaning Methods 6
Aqueous Cleaning 6
Media Blasting 7
Carbon Dioxide Blasting 7
Supercritical Carbon Dioxide 8
Chapter 3 Technical Evaluations 9
Introduction 9
Quality Assurance Plan 9
Parker Hannifin Corporation 11
Pressure Spray Washers 12
Ultrasonic System 12
Immersion Tank 12
Technical Evaluation 15
Testing in TURI's Surface Cleaning Laboratory 15
Technical Evaluation Supplement 16
Market Forge : 17
Problems with Cleaning Carbon Steel 17
Problems with Cleaning Aluminum 18
Technical Evaluation 18
Cleaner Systems Testing 18
-------
-------
QA Results 21
Company A 22
Identification of Options 23
Evaluation of Options 24
Media Blasting 24
Ultrasonics 25
Supercritical Carbon Dioxide 25
New Vapor Degreaser 26
Retrofit Existing Vapor Degreaser 26
Implement AVD™ System 26
Chapter 4 Investment Analysis 30
Introduction 30
Total Cost Assessment 30
Data Collection 31
Parker Hannifin: Analysis One . . 32
Background 32
Cleaning Operations 32
Capital Costs 32
Operating Costs 33
Chemicals and Wastes 33
Regulatory Costs 34
Production and Maintenance Costs 35
Utility Costs 35
Project Outcome 35
Parker Hannifin: Analysis Two 37
Background 37
Cleaning operations 37
Capital Costs 37
Operating Costs [ 38
Chemicals and Wastes 38
Regulatory Costs 40
Production and Maintenance Costs 40
Utility Costs 40
Comparison to Company Financial Assessment 41
Project Outcome 41
Market Forge Financial Analysis 42
Background .....'. 42
Cleaning Operations 42
Capital Costs .42
Operating Costs , 43
Chemicals and Wastes 43
Regulatory Costs 44
Production and Maintenance Costs 44
Utility Costs 44
Project Outcome 45
Company A Financial Analysis 47
Background 47
vi
-------
Cleaning Operations 47
Capital Costs 48
Operating Costs 48
Chemicals and Wastes 48
Regulatory Costs 50
Production and Maintenance Costs 50
Utility Costs 50
Project Outcome 51
Conclusions 51
Chapter 5 Substitution Analysis 55
Introduction 55
Substitution Analysis and the Decision Making Process 56
Performing a Substitution Analysis 57
Using the Worksheet 57
Limitations 61
Conclusions 61
Chapter 6 Overall Conclusions 62
References _ 64
Appendix A Quality Assurance, Calibration and Sampling Methods 68
Quantitative QA Objectives 68
Calibration Procedures and Frequency 68
Sampling Procedures 68
Appendix B TURI Surface Cleaning Laboratory Cleaner Performance Report 69
Appendix C Case Studies Documenting Success of Closed Loop Aqueous Degreasirag 71
AppendixD Pay-back Period and Net Present Value 72
Appendix E Substitution Analysis Worksheet 75
Appendix F Definitions of Criteria 77
Appendix G Substitution Analysis Worksheet - Market Forge 82
Appendix H Substitution Analysis Worksheet - Company A 84
Appendix I Information Resources , 90
Appendix J Annotated List of Substitution Analysis References 91
Vll
-------
List of Tables
1. Summary of Chlorinated Solvent Properties 4
2. Parker's Toxics Use Reduction Act Data Pounds of Solvents Otherwise Used, 1990-1994 12
3. Summary of Aqueous Chemistries 16
4. Average Removal Efficiency for Three Chemistries on Steel Parts: Market Forge Application 19
5. Options Analysis Summary: Company A 28
6. Parker Hannifin Analysis One - Capital Costs 32
7. Parker Hannifin Analysis One - Operating Costs . 33
8. Parker Hannifin Analysis One: Option Analysis Summary 36
9. Parker Hannifin Analysis Two - Capital Costs 38
10. Parker Hannifin Analysis Two - Operating Costs 39
11. Parker Hannifin Analysis Two: Option Analysis Summary 41
12. Market Forge - Capital Costs 43
13. Market Forge - Operating Costs 45
14. MarketForge - Option Analysis Summary •„ 46
15. Company A - Capital Costs 48
16. Company A - Operating Costs 49
17. Cost Categories as a Percent of Total Operating Costs 53
18. Summary of Comparison of the Substitution of 1,1,1-Trichloroethane for Naphtha Solvent 59
19. Summary of Substitution Comparison of the Options to Replace TCE 60
vui
-------
List of Figures
1. Laboratory Evaluation Protocol : JQ
2. Schematic of Parker Hannifin Vapor Degreasing Systems ] ° | 13
3. Schematic of Parker Hannifin Aqueous Degreasing System ; 14
4. Market Forge Metal Cleaning System 20
5. Company A TCE Vapor Degreaser 22
6. Company A Cleaning and Surface Preparation Process 23
IX
-------
Acronyms and Abbreviations
1,1,1-TCA 1,1,1-Trichloroethane
BOD Biochemical Oxygen Demand
CAAA Clean Air Act Amendments
DOT Department of Transportation
DI De-ionized Water
EPA Environmental Protection Agency
FT-IR Fourier transform-infrared spectrometry
HAP Hazardous Air Pollutant
HEPA High Efficiency Particulate Air
IARC International Agency for Research on Cancer
IDLH Immediately Dangerous To Life or Health
LCA Life Cycle Analysis
LFL Lower Flammability Limit
MACT Maximum Available Control Technology
METH Methylene Chloride
MSDS ' Material Safety Data Sheet
NAAQS National Ambient Air Quality Standards
NASA National Aeronautics and Space Administration
NESHAP National Emission Standard For Hazardous Air Pollutants
NOAEL No Observed Adverse Effect Level
NRMRL National Risk Management Research Laboratory
OSEE Optically stimulated electron emission
OSHA Occupational Safety and Health Administration
PEL Permissible Exposure Limit
PEKC Perchloroethylene
PNEC Predicted No-Effect Concentration
QA Quality Assurance
QAPP Quality Assurance Project Plan
RCRA Resource Conservation and Recovery Act
SARA Superfund Amendments and Reauthorization Act
SCF Supercritical fluid
TCA Total Cost Assessment
TCE Trichloroethylene
TLV Threshold Limit Values
TRE Toxics Release Inventory
TURA Toxics Use Reduction Act
TURI Toxics Use Reduction Institute
TWA Time Weighted Average
UF1L Upper Flammability Limit
US United States
VOC Volatile Organic Compound
-------
Acknowledgments
The authors would especially like to thank Rene Doucet, John Moynihan, Sal Candelora and Fred Bartlett
of Market Forge; Stephen Brooks, Philip Dowd and David Harris of Nichols Aircraft Division; the
personnel of Company A for their time and patience providing the facts and numbers that were essential to
this report.
Lisa Brown and Paul Randall, EPA Project Officers, made this project possible.
The authors acknowledge Mark Rossi, Elizabeth Harriman and Monica Becker of the Tojcics Use
Reduction Institute for the original project design and for advice throughout.
Arjan vanVeldheuizen's contributions to the total cost assessment data collection and analysis for Chapter
4 were much appreciated.
The authors would like to thank Carole LeBlanc, Jay Jankauskas, Donald Garlotta and John Bulko for their
individual contributions to the lab work performed in TURTs Surface Cleaning Lab.
The authors also acknowledge Mark Hensley for his editorial comments. Finally, the authors would like to
thank Maureen Hart for her editorial comments on the final document
-------
Executive Summary
The Clean Alternatives Project consisted of technical, financial and substitution (environmental, health and
safety) analyses of alternatives to chlorinated solvents used for metal degreasing. The project focused, on
three 33/50 chemicals: dichloromethane, 1,1,1-trichloroethane and trichloroethylene. Three Massachusetts
companies participated in this project. All three were at different stages of the conversion away from
chlorinated solvent cleaning. The three situations offered different lessons about the success and
applicability of alternative cleaning processes.
The project was organized into five phases, with the following objectives:
Phase 1: to identify uses and users of the 33/50 metal degreasing solvents in Massachusetts,
Phase 2: to evaluate the technical feasibility of alternative cleaning technologies and chemistries to
33/50 solvents in metal degreasing applications,
Phase 3: to perform a total cost assessment on the cleaning alternatives for each case,
Phase 4: to perform an environmental impact'assessment for each case, and
Phase 5: to perform technology transfer of project results.
In phase 1, uses and users of the 33/50 metal degreasing solvents in Massachusetts were identified using
data generated by companies for the Massachusetts Toxics Use Reduction Act and by data from the federal
Community Right-To-Know Act From these data, the three participating companies were chosen based
on current uses and potential transferability of results.
During the phase 2 technical analysis, alternatives to the chlorinated solvents were identified, demonstrated
and evaluated. The three companies that participated in this project were Parker Hannifin Corporation,
Market Forge and Company A. At its Waltham, Massachusetts facility, Parker Hannifin manufactures
pumps for aircraft engines under primary SIC code 3724. In 1992, the company began to investigate tide
replacement of their two vapor degreasers with an aqueous cleaning system. The original idea was to
replace both vapor degreasers with one immersion cleaning system that could satisfy their highest
cleanliness needs. After careful consideration of cleaning needs and logistics, the company decided to
replace the vapor degreasers with three pressure spray washers for frequent remote cleaning following
machining, one ultrasonic unit for the highest cleanliness needs and one immersion tank for cleaning
following heat treatment, Parker Hannifin was chosen to document a situation 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 for Parker Hannifin in
order to make improvements to their current aqueous cleaning 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 prior
to welding. The performance of TCA was satisfactory, but its use was discontinued because of the
labeling requirements of the Montreal Protocol. On the advice of their supplier, a switch was made from
TCA to an aliphatic petroleum distillate solvent (CAS 64742-88-7). As soon as the switch was made, the
welders of both the carbon steel and aluminum parts began to experience problems. Market Forge was
chosen as a company in the difficult transition stage. A technical evaluation was performed to find a
xn
-------
suitable cleaning process and chemistry to replace the petroleum distillate. Based on the information
obtained from this project, Market Forge purchased an American Metal Wash pressure spray washer. The
unit was recently installed and has been operating effectively for four months.
Company A is a job-shop electroplating company located in Massachusetts. By the nature of the job-shop
business, Company A cannot always predict what types of metals it will have to clean and thus requires a
flexible .cleaning system, capable of cleaning many different substrates. Currently the company cleans all
their parts in a vapor degreaser using TCE. Company A was chosen because their situation is one shared
by many job-shop platers in the northeast, namely, a wide variety of substrates and contaminants. A
technical assessment identified the following alternatives for further study: media blasting using sodium
bicarbonate, plastic or carbon dioxide, ultrasonic aqueous, "closed" vapor degreasing, upgrading the
existing vapor degreaser, Advanced Vapor Degreasing (AVD™) system, and supercritical carbon dioxide.
Some general conclusions were drawn from the technical evaluation phase in regard to chemical
compatibility/process specification and "drop-in" replacements. For chemical compatibility/ process
specification, it was concluded that rinsing of a non-silicated cleaner is not always necessary even when a
painting Operation follows and aqueous immersion cleaning can be a viable option for steel and aluminum
substrates either prior to nitriding or following heat treat operations. With regard to "drop-in"
replacements, it was concluded that a thorough technical evaluation of so-called "drop-in" replacements is
necessary to avoid unforeseen costs and that job shops present an (as yet) unmet challenge to the vendors
of "drop-in" replacements.
For the financial analysis in phase 3, a total cost assessment methodology was used to perform financial
analyses of the alternative cleaning processes. Some general conclusions were made:
>• 1) if the aqueous systems are replacing older solvent-based equipment, a savings In electricity
costs may be realized, especially if hot air drying is not required; >
*• 2) depending on the cooling capacity of the vapor degreaser, the aqueous systems may actually use
less water,
* 3) the profitability of an investment in aqueous cleaning equipment can be improved by
purchasing based on cleaning needs at different stages in the production process;
»• 4) the aggressive taxes on CFC's and TCA have made aqueous alternatives feasible economically;
and
»• 5) the Total Cost Assessment methodology (P2/Finance Software) can be used in an iterative
process 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 requirement could be met for a
certain "cost" rather than actually attempting to place a value on meeting the regulatory
requirement
A substitution analysis methodology was developed during phase 4 and was used to evaluate the
environmental, occupational, and public health effects of the alternative cleaning processes. The
substitution analysis described is qualitative in nature. It allows the comparison of alternatives using many
criteria, but a final decision as to the best alternative must be made by the investigator. Described in
worksheet format, this approach highlights both the areas of concern for alternative substitute processes
and areas where those substitutes clearly are superior to the current process. The worksheet will aid the
decision maker in making informed decisions without overlooking important issues.
Xlll
-------
Finally phase 5, the information dissemination phase of the project, resulted in technical fact sheets,
conference presentations, workshops, and the final EPA report This work is part of a larger program at
the Toxics Use Reduction Institute that includes laboratory assistance to companies through TURTs
Surface Cleaning Laboratory, Research Fellows projects oh "closed-loop" aqueous cleaning systems and
further development of the substitution analysis, and the preparation of a manual "Cleaning is Greener in
Massachusetts" in conjunction with the Office of Technical Assistance for Toxics Use Reduction.
This project studied three principle 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 other competing substitute technologies. The steps can be
performed in any order and their relative importance can vary from project to project The technical
evaluation of a potential replacement process for an existing technically successful process is often the
most important evaluative step. The success or failure of the technical evaluation determines whether or
not the process will be evaluated further. Complete technical evaluation at the lab and pilot scale levels
can lead to a smooth transition into the new process. An incomplete, technical evaluation can lead to
unforeseen problems with the incorporation of the new process and necessitate further evaluation following
installation. An economic evaluation of a technically-proven chemical or process provides valuable
information affecting the decision to implement or not Traditional financial analysis, however, often
includes only the costs directly 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 such things as staff time for environmental reporting, waste
management costs, and permitting fees. The results of the financial assessment further inform the decision
to adopt or not However, technical and financial information combined is not the final word in decision
making. Further evaluation is required to assess the environmental, health and safety issues involved with
the chemicals and processes. While the technical and cost assessments are not simple, the environmental,
health & safety assessment, called substitution analysis, is perhaps the most difficult because there is no
generally agreed on and reliable method for evaluating the environmental and worker health and safety risk
of alternatives.
In using the three evaluative steps described above, it is important to remember 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 companies had different
motives for seeking substitute technologies. This in turn, dictated which evaluative step was most
important to mem and indicates that the results of any one of the three can be the driving factor in a
decision. Despite the emphasis being placed on one evaluative step on a given project, all three aspects
must be evaluated so that valuable pieces of information are not ignored.
XIV
-------
Chapter 1
Introduction
Introduction
Cleaning and degreasing of metal parts in the metal finishing and metal working industries has traditionally
been accomplished by the use of chlorinated solvents in vapor degreasers or immersion systems. In this
context, cleaning and degreasing is, simply, the removal of contamination from the metal surface. This
function is either 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 chloride or METH) and chlorofluorocarbons. Chlorinated solvents are
effective cleaners and, hi the past, have been considered "safe" to workers because they are nonflammable.
Due to concern over the ozone layer, photochemical smog and worker health, increasingly strict
environmental regulations have been promulgated on the use of chlorinated solvents. The result has been
higher costs associated with the purchase 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 ineffective cleaners, too expensive, or present safety hazards. A careful evaluation of the
options can help in selecting the most cost effective and technically feasible solution without
compromising worker health and safety or environmental protection.
EPA's 33/50 Program
As a part of EPA's pollution prevention1 strategy, the Agency initiated the 33/50 Program. This was a
voluntary pollution prevention program to reduce'national releases and off-site transfers of 17 toxic
chemicals. The Toxics Release Inventory (TRI), established by the Emergency Planning and Community
Right-to-Know Act of 1986, was used to track these reductions using 1988 data as a baseline.
The 33/50 Program had three basic goals. First, the EPA aimed to reduce national aggregate
environmental releases of the 17 target chemicals from 1988 levels by 33% by the end of 1992 and by 50%
by the end of 1995. Second, the EPA encouraged companies to use pollution prevention practices rather
than end-of-pipe treatment to achieve these reductions. Third, the EPA hoped that this program would
help foster pollution prevention practices and principles in American businesses whereby companies would
routinely analyze all their operations to reduce or eliminate pollution before it was created.2
1 Pollution prevention is defined by EPA as "the use of materials, processes, or practices that reduce or eliminate the creation of
pollutants or wastes."
2 EPA, Office of Research and Development, "Opportunities for Pollution Prevention Research to Sepport the 33/50 Program",
EPA/600/R-92/175, October 1992.
1
-------
EPA's National Risk Management Research Laboratory (NRMRL, formerly Risk Reduction Engineering
Laboratory) funded research in support of the 33/50 Program. The broad goal of the research was to
evaluate pollution prevention options for the 17 target chemicals and to disseminate the results of the
evaluations. The Clean Alternatives Project was funded by a grant from NRMRL to the Toxics Use
Reduction Institute3 (TURI) at the University of Massachusetts Lowell.
Overview of the Clean Alternatives Project
The Clean Alternatives Project consisted of technical, financial, and substitution (environmental, health
and safety) analyses of alternatives to chlorinated solvents used for metal degreasing. Three of the 33/50
chemicals commonly used for surface cleaning are dichloromethane, 1,1,1-trichloroethane and
trichloroethylene. These three chemicals were the focus of this project.
Three Massachusetts companies participated in this project. During the technical analysis, alternatives to
the chlorinated solvents were identified, demonstrated and evaluated. For the financial analysis, a total
cost assessment methodology was used to perform financial analyses of the alternative cleaning processes.
A substitution analysis methodology was developed and used to evaluate the environmental, occupational,
and public health effects of the alternative cleaning processes.
This report of the Clean Alternatives Project supplements four other recent reports on the subject Guide
to Cleaner Technologies: Alternatives to Chlorinated Solvents for Cleaning and Degreasing, Guide to
Cleaner Technologies: Cleaning and Degreasing Process Changes, and Federal Facility Pollution
Prevention Project Analysis: A Primer for Applying Life Cycle and Total Cost Assessment Concepts, all by
the US EPA and Demonstration of Alternative Cleaning Systems by The Center for Clean Products and
Clean Technologies at the University of Tennessee.
The Clean Alternatives Project adds the following information to the body of literature:
*• alternative demonstrations to chlorinated solvents for metal degreasing '
> the role of total cost assessment in the decision making process
»• the inclusion of worker health and safety concerns in a substitution analysis and
*• the documentation of a substitution analysis methodology.
The Toxics Use Reduction Institute is a multi-disciplinary research, education, and policy center established by the
Massachusetts Toxics Use Reduction Act of 1989. The Institute sponsors and conducts research, organizes education and
training programs, and provides technical support to promote reduction in the use of toxic chemicals or in the generation of
toxic chemical-byproducts in industry and commerce.
-------
Chapter 2
Methods and Materials for Surface Cleaning
Cleaning is a surface preparation process that removes contaminants and prepares parts for subsequent
operations. The purpose of this chapter is not to give a detailed overview of all cleaning methods available
but to address the cleaning methods used and considered by companies in this project For a more
complete description of current alternative cleaning processes as well as emerging technologies, consult
EPA's Guide to Cleaner Technologies: Alternatives to Chlorinated Solvents for Cleaning and Degreasing.
Vapor Degreasing
Degreasing is an integral part of almost all metalworking and maintenance operations. It is used to remove
oils, greases, waxes, tars, and moisture, preparatory to further surface treatment such as electroplating,
painting, galvanizing, anodizing, and applying conversion coatings. Surface cleaning is also carried out in
plastics fabrication and in the electrical, electronics and printing industries. .
A vapor degreaser is a tank with heating coils in the bottom and a condensing zone near the top. The
temperature of the solvent in the tank is raised to near boiling and the hot solvent vapor fills the tank up to
the condensing zone. The vapor condenses on the dirty workpiece, dissolves the contaminants and drains
back into the solvent reservoir. Solvent losses occur mainly when the vapor zone is disturbed by air drafts,
when the workload is lowered into or raised out of the machine, or when the parts drag oiat condensed
solvent The chlorinated cleaning solvents used for the vapor degreasing situations analyzed for this
project were TCE, 1,1,1-TCA, METH and CFC-113 (or Freon TF). (Note: CFC-113 is not part of EPA's
33/50 Program but was included in this report because one company previously used it)
Prior to the 1970s, the vapor degreasing market was dominated almost completely by TCE. In the mid-
1960s it was discovered that TCE was photochemically reactive and that its emissions contributed to smog
formation. This led to limitations on its use. In some cases, these restrictions resulted in the replacement
of TCE by less photochemically reactive solvents, although other companies continued to use TCE by
reducing emissions. In 1975, TCE was identified as a carcinogen to mice and concern was expressed
regarding worker exposure to its vapors.
TCE was often replaced by CFC-113,1,1,1-TCA, arid METH as more environmentally acceptable and less
toxic replacements in vapor degreasing. Since the physical properties of 1,1,1-TCA are similar to those of
TCE, it could be used as a drop-in replacement for TCE with only minor modifications. The use of
CFC-113 and METH required additional equipment or procedural modifications. Table 1 shows how the
properties of these four chemicals compare.
In the mid-seventies, CFCs and 1,1,1-TCA were found to contribute to the depletion! of the earth's
protective stratospheric ozone layer. As a result, these two cleaning agents are being phased out under the
Clean Air Act as amended in 1990 and The Montreal Protocol on Substances that Deplete the Ozone Layer
(a 1992 international agreement on the phasing-out of ozone depleting chemicals). The original protocol
included only the phasing out of CFCs because of their higher ozone-depleting potential. Later, 1,1,1-
i
3
-------
1CA was included in the amendment of the protocol because of the quantities used. In January 1992,
NASA testing revealed the highest level of ozone-depleting substances ever. These findings have
prompted an acceleration of the phase-out schedule from the original goal of the year 2000 to a phase-out
by January 1, 1996. "- •
METH and TCE are considered hazardous air pollutants under the 1991 Clean Air Act Amendments.
Within ten years, the EPA will require major users to install maximum available control technology
(MACT) to limit emissions. CFC-113 is mildly acutely toxic by ingestion and inhalation. TCE,
1,1,1-TCA and METH are suspected carcinogens as shown in Table 1.
Table 1. Summary of Chlorinated Solvent Properties
Property
photo-chemically reactive
ozone depletor
HAP
vapor density (air =1)
boiling point
carcino-genicity4
TCE
yes
no
yes
4.53
86-88 C
suspected
1,14-TCA
no
yes
no
4.63
72-88 C
suspected
METH
no
no
yes
2.93
39.4-40.4 C
suspected
CFC-113
no
yes
no
6.5
47.6 C
no
Solvents Used in Vapor Degreasing
Trichloroethylene
The main advantages of TCE, chemical formula C1CH=CC12, are high vapor density and excellent stability,
particularly when compared to 1,1,1-TCA. TCE is aggressive on dirt and oils and does not leave a film or
other residue; furthermore it is easy to recycle. TCE has a big advantage over METH in that it is a drop-in
replacement for 1,1,1 -TCA.
In the US, consumption of TCE for degreasing has declined over the years, from about 337 million pounds
in 1974 to approximately 92 million pounds in 1993s. Over 90% of the total consumption of TCE is for
vapor degreasing. The consumption of TCE in 1995 is projected to be higher than in recent years, as it
may be used to replace 1,1,1-TCA. However, toxicity concerns may curb its widespread use as a substitute
for 111-TCA. According to the 1991 Massachusetts TURA data, SIC codes 33,34,36, and 38 accoumt for
over 96% of all TCE used for metal cleaning. These industries include primary and fabricated metal
industries, electronic and other electric equipment manufacturing, and instruments and related products.
TCE is a suspected carcinogen. Human systemic effects and mutation data have been reported. A form of
addiction has been observed in exposed workers. Prolonged inhalation of moderate concentra
4 Lewis, Richard J., Sr., "Sax's Dangerous Properties of Industrial Materials", 1992.
5 SRI International, "Chemical Economics Handbook", 1995.
-------
)
A.
dons causes headache and drowsiness. There is damage to the liver and other organs from chronic
exposure.6
1,1,1-Trichloroethane
1,1,1-Trichloroethane or 1,1,1-TCA, chemical formula CC13CH3, is a good solvent for oils, greases, waxes,
tars, fats, gums, and resins. It is the preferred solvent for cleaning electronic components, electrical parts
and printed circuit boards where other solvents might damage insulation or cause heat warpage. Cleaning
with 1,1,1-TCA in vapor degreasers does not require as high a temperature as cleaning with TCE.
The main technical shortcomings in the use of 1,1,1-iTCA is its chemical stability. Relatively large
amounts of stabilizers, as compared to other vapor degreasing solvents, must be added to avoid degradation
of the solvent If the stabilizer levels are below a certain minimum, 1,1,1-TCA may undergo hydrolysis in
the presence of water and a potentially dangerous acid-forming reaction with aluminum.
The estimated U.S. consumption of 1,1,1-TCA for metal cleaning was 175 million pounds in 1993. Of
this amount, 70% was for vapor degreasing and 30% for cold cleaning applications.7
1,1,1-TCA is classified as a suspected carcinogen and an experimental teratogen. Human systemic effects
have been reported. The chemical is narcotic at high concentrations.8
Methylene Chloride
Methylene chloride or METH, chemical formula CH2C12, is effective on a wide variety of substrates! and is
relatively inexpensive. It has the ability to penetrate rapidly into a coating, causing the coating to swell and
lift off the substrate. This makes the coating very easy to remove. METH is also aa aggressive solvent to
many fats, oils, greases, polymers, waxes, tars, lacquers, and natural and synthetic rubbers. METH has the
lowest boiling point of the solvents used in vapor degreasing. It can be used when the temperatures
required for higher-boiling solvents might damage the part
As a vapor degreasing solvent METH has a relatively low vapor density (three times heavier than air,
while other solvents are 4.5-6.5 times heavier) and high evaporation rates. Therefore degreasers using
methylene chloride require more cooling capability than those using other solvents. If adequate cooling is
not supplied, the low vapor density and high evaporation rate of METH result in greater solvent loss and
higher consumption than the competing solvents.
In several animal lexicological studies, inhalation of METH was found to cause liver cancer. As a result
the EPA has classified METH as a "probable" cause of cancer in humans. It is known that the chemical is
irritating to skin, eyes and the respiratory tract. It is a central nervous system depressant and causes
narcosis at high levels.
METH has an estimated 5-10% of the U.S. market for metal cleaning. In 1993, the U.S. consumption of
methylene chloride for metal cleaning was 15 million pounds out of a total consumption of 237 million
6 Lewis, Richard J., Sr., "Sax's Dangerous Properties of Industrial Materials", 1992,
7 SRI International, "Chemical Economics Handbook", 1995.
1 Lewis, Richard J., Sr., "Sax's Dangerous Properties of Industrial Materials", 1992.
5
-------
pounds.9 According to the 1991 Massachusetts TURA data, SIC code 36, electronics and electrical
equipment manufacturing, accounts for over 50% of all METH used for metal cleaning.
.•t* -' "'*?!* • " - - 'a^W -£&.'•"
CFC-113
CFC-113, chemical formula Cf3 C13, is also known as Freon TF and trichlorotrifluoroethan. CFC-113 is
not part of the EPA's 33/50 Program but is used as a vapor degreasing solvent Before it was found to be
ozone depleting, CFC-113 was widely used in cleaning applications because it was available and
inexpensive. CFC-113 easily removes many different contaminants from many different substrates. In
addition, it is less toxic to humans than 1,1,1-TCA, METH or TCE. Prices for CFCs and the cost of waste
management have increased dramatically since the Montreal Protocol.
Alternative Cleaning Methods
Because of the worker and environmental health concerns with solvent-based metal cleaning methods, a
number of alternative cleaning methods are being developed. These include aqueous cleaning, media
blasting, carbon dioxide blasting, and supercritical carbon dioxide.
Aqueous Cleaning
Waiter-based and semi-aqueous cleaners will, most likely, be favored over the many possible replacements
for chlorinated solvents. Income applications, hot water alone may be sufficient to clean parts. When a
detergent is required, synthetic detergents and surfactants use water as the primary solvent. Synthetic
detergents and surfactants are combined with special additives such as builders, pH buffers, inhibitors,
saponifiers, emulsifiers, deflocculants, complexing agents, and anti-foaming agents. These agents provide
multiple degrees of freedom hi formulating, blending, and concentrating, and also provide useful
synergistic effects.
Semi-aqueous cleaners are made of natural or synthetic organic solvents, surfactants, corrosion inhibitors,
and other additives. Water is used in some part of the cleaning process (washing and/or rinsing), hence the
name, semi-aqueous. Some common semi-aqueous cleaners are the water-immiscible types such as
terpenes, high-molecular-weight esters, petroleum hydrocarbons, and glycol ethers and the water-miscible
types such as low-molecular-weight alcohols, ketones, esters, and organic amines. These cleaners are
noii-ozone-depleting but they may contain volatile organic compounds. Therefore, their use raises more
concerns about aquatic toxicity and human exposure than does the use of aqueous cleaners.10
Large-scale metal cleaning operations and captive shops may find it relatively easy to make the switch to
these cleaners since, generally, water-based or semi-aqueous cleaners can be formulated to remove sjpecific
types of contaminants from given metal surfaces. For job shop operations or those with continually
changing cleaning needs, the switch is much more difficult These users may continue using chlorinated
solvents because of their greater versatility. Also, some companies may hot have adequate or existing
wastewater discharge permits, which could be required for the disposal of aqueous cleaning solutions.
The aqueous based cleaning systems addressed in this report can be divided into three cleaning methods:
immersion, spray, and ultrasonic. The immersion method cleans the parts by immersing them in a solution
9 IB
SRI International, "Chemical Economics Handbook", 1995.
10 USEPA, Office of Research and Development, "Guide to Cleaner Technologies: Alternatives to Chlorinated Solvents for
Cleaning and Degreasing," February 1994.
-------
and using some form of agitation to add the energy needed to displace and float away contaminants. Soil
is removed from the metal surface by convection currents created by heating coils or by some mechanical
action.
The spray washing method cleans parts with a solution sprayed at pressures from as low as 2 pounds per
square inch (psi) to more than 400 psi. The higher spray pressure delivers more mechanical action to help
remove soils from metal surfaces. Spray cleaners are prepared with low foaming detergents that are not as
chemically effective as those used in immersion cleaners, but are still effective because of the increased
mechanical action. Although spray cleaning is effective on most parts, certain part configurations, such as
the interior of an automobile tail pipe, have soiled areas that are inaccessible to the spray cleaning solution.
In these instances, immersion cleaners are more effective.
The ultrasonics method combines water, a detergent, and high frequency sound waves to provide the
agitation. Ultrasonic cleaning uses sound waves in the 20 to 50 KHz range to produce cavitation bubbles
in water. As the cavitation bubbles collapse and implode, it has been calculated that temperatures in
excess of 10.000F and pressures in excess of 10,000 psi are generated.11 The mechanical effect of the
ultrasonic energy helps to dissolve and displace particles from the surface of the work piece.
Media Blasting
The media blasting process, in general, combines a certain abrasive media, a pressurized delivery system
and one of a variety of cleaning chambers. Typically called impact or abrasive cleaning, this method of
cleaning leaves no residue. Abrasive cleaning is not appropriate for grossly contaminated parts because
the contaminants cause the media to stick together. However, media cleaning is appropriate for "normal"
machining oils and contaminants. Glass beads and sand have been used as media in this process for years
with the more recent introductions of plastic and sodium bicarbonate. These new media allow the
technology to be used on a wider variety of substrates. Glass beads are compatible with 90% of substrates.
Glass beads range in size from 840 microns to 88 microns. For stainless steel and other steels, glass beads
in the 250-145 micron range are most effective. Glass beads may leave a matted finish on some softer
metals unless the air pressure is correctly adjusted. Plastic media may be more appropriate for aluminum,
but do not work as well on steel and stainless steel. Sodium bicarbonate is a relatively new media and has
shown promise in many applications.
Carbon Dioxide Blasting
Carbon dioxide (COj) technology begins with the conversion of liquid CO2 into solid CO2. There are at
least three carbon dioxide technologies in use: CO2 snow, CO2 pellet, and fragmented CO2. In all forms,
the cleaning action of the CO2 is the same. As the material impacts the surface to be cleaned, it subMmes,
returning to the gaseous state. The cleaning occurs as the sublimation causes turbulence on the surface and
lifts the contaminants away. The contaminants and the CO2 gas are passed through a high efficiency
paniculate air filter (HEPA) where the particulates are collected and the gas is released
Carbon dioxide snow is formed when liquid CO2, which is allowed to expand to atmospheric pressure
through a nozzle, forms soft flakes. CO2 snow technology can remove particles and debris without damage
to the surface. CO2 snow cleaning is effective for dust and dirt but not necessarily grease unless the
pressure is between 400-800 psi. CO2 pellet technology compresses CO2 snow into hard pellets that are
blasted toward a surface with a high pressure carrier gas, typically compressed air. The pellet process can
11 Fuchs, John R, "Ultrasonic Cleaning Fundamental Theory and Application", Blaskstone Ultrasonics, Jamestown, NY.
7
-------
remove paint and rust but there is a greater risk of harming the surface than with CO2 snow. Pellets are
effective at removing oil and grease at relatively low pressures. These CO2 techniques have been used for
precision cleaning applications in the aerospace and electronics industries for about 12 years.12
Fragmented CO2 is a relatively new technology where the CO2 solid particles are randomly shaped, unlike
pelletized CO2, which has uniform shape. Fragmented CO2 requires less equipment resulting in lower
capital cost It is also effective at removing oils and greases at relatively low pressures.
Supercritical Carbon Dioxide
Supercritical fluids (SCFs), which result from subjecting substances to temperatures and pressures above
their critical points, possess properties intermediate between liquids and gases. Precision surface cleaning
with SCFs takes advantage of these unique properties, such as liquid-like density and solvency combined
with gas-like viscosity and diffusivity. SCFs can rapidly penetrate substrates and small interstitial spaces,
dissolve the contaminants, and then be easily and completely removed since the SCF lacks surface tension.
SCF cleaning is typically a batch process performed using a system consisting of two primary pressure
vessels (a cleaning chamber and a separator), high pressure pumps, pressure regulators, pressure reduction
valves, and interconnecting piping. Initially, a liquid (in this case, COj) is pumped into the cleaning
vessel, which is then pressurized to the operating conditions. At this point, the cleaning chamber, wMch
contains parts totally immersed in supercritical CO2, is isolated from the rest of the system. The cleaning
process itself may involve simple immersion of the parts in the SCF for a given time period, or may
incorporate SCF agitation and recirculation, and/or displacement of the contaminated SCF with fresh SCF.
At the end of a cleaning cycle, additional fresh CO2 is pumped into the cleaning chamber to displace the
contaminated CO2. The contaminated CO2 is sent through a pressure reduction valve and vaporizes in the
separator. CO2 vapor exits from the top of the separator, while the non-volatile contaminants are collected
in the bottom. Recovery and reuse of the CO2 may be economically justified depending on the process
scale.
12 Pollution Prevention Advisor, "COj Does Snow Job on Contaminated Surfaces". Volume 5, Number 5, May 1995.
8
-------
Chapter 3
Technical Evaluations
Introduction
The technical evaluation of a potential replacement process for an existing technically successful process is
perhaps the most important evaluative tool. The success or failure of the technical evaluation determines
whether or not the process will be evaluated further. Complete technical evaluations at the lab and pilot
scale levels can lead to a smooth transition into the new process. An incomplete technical evaluation can
lead to unforeseen problems with the incorporation of the new process and necessitate further evaluation
following installation. Using data generated by companies for the Massachusetts Toxics Use Reduction
Act and by data from the Federal Community Right-To-Know Act, three companies were chosen to
participate based on current uses and potential transferability of results. All three were at different stages
of the conversion away from chlorinated solvent cleaning. The three situations offered different lessons
about the success and applicability of alternative cleaning processes.
Parker Hannifin was chosen to document a situation 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 for Parker Hannifin in order to make improvements to
their current aqueous cleaning process.
Market Forge was chosen as a company in the difficult transition stage. The elimination of their
chlorinated degreasing solvent, trichloroethane, was a management mandate at their facility. They had
tried some vendor recommended "drop in" replacement solvents that had failed for their application. A
technical evaluation was performed to find a suitable cleaning process and chemistry.
Company A was chosen because their situation is one shared by many job shop platers in the Northeast,
namely, a wide variety of substrates and contaminants. A technical evaluation was performed to identify
alternatives for further study.
Quality Assurance Plan
A document titled Quality Assurance Project Plan for Evaluation of Alternative Surface Cleaning
Methods was prepared for this project As required by the National Risk Management Research
Laboratory, this document outlines the quality assurance (QA) objectives, defines sampling, analytical, and
calibration procedures, plans for checks on quality control and details corrective action should it be
necessary.
The QA objectives associated with performing the technical feasibility assessments of this research project
were three-fold:
> to establish the level of cleanliness for each case using current cleaning methods as a
baseline reference,
-------
to demonstrate the technical feasibility of alternate cleaning chemistries on actual
company parts or test materials, or, in the case of Parker Hannifin, to determine the cause
of cleaning problems in the current aqueous process,
to identify technically feasible alternatives to the chlorinated hydrocarbon solvents
currently used in metal degreasing operations at Market Forge and Company A.
Establish Baseline "Clean"
Substrate Identification: metal test coupons or company supplied parts
Standardized Cleaning Procedure: must be performed prior to contamination step in order to
establish a baseline clean
example: 15 minute ultrasonics wash @ 140°F, 10 % solution Daraclean 232 cleaner, 5 minute
immersion rinse @ 140°F in tap water, 5 minute immersion rinse @ 140°F in DI water, 10
minute dry @ ambient temperature Laminaire Row Station, 30 minute dry @ 158°F oven, cool
to ambient conditions .
Gravimetric Analysis of "Cleaned" Substrates: determine weight of cleaned coupons before
contamination
Supplemental Analytical Characterization: establish baseline readings for the "clean" substrate
(FT-IR/Grazing Angle Reflectance, OSEE).
Contamination Protocol
»• Designate Contaminant: cutting oils, lubricants, greases, coolants, particulates, chips and fines,
oxidation products, fingerprints, waxes, aqueous-based, synthetic, petroleum-based, natural
products
> Contaminant Application: loading is dependent on the method used. Range: 0 mg/sq cm to
customer specified level
•• Application Method: spray on soil/solvent solution; roll/wipe-on using brush; dip/soak in
soil/solvent solution; other "as received" from customer
> Drying Process: dry/age in air for 24 hrs. or dry/process at elevated temperature
»• Gravimetric Analysis of Contaminated Coupons: determine contaminated loading (mg/sq cm)
» Supplemental Characterization: OSEE, FT-BR. to establish readings for the "dirty" substrates
Cleaning, Rinsing, and Drying Protocol
> Select Substrate Material for Contamination: ferrous, non-ferrous, plated alloys
»• Select Cleaning Chemistry from technical literature, product bulletin, MSDS, manufacturer,
distributor
> Select Appropriate Number of Test Materials for statistical validation and design of
experimental trials based on the number of experimental variables chosen
» Select Process Cleaning Equipment: ultrasonics, soak immersion, agitated immersion,
pressure/spray wash
>• Selected Variables to Investigate: wash time (1 to 15 minutes), wash temperature (70-190"F),
concentration of cleaning solution (start with manufacturer's recommendations)
Figure 1. Laboratory Evaluation Protocol
10
-------
Figure 1 outlines the Laboratory Evaluation Protocol developed by TURI's Surface Cleaning Laboratory
for evaluation of alternative cleaning chemistries. First, a baseline "clean" must be established on
company supplied parts if possible or on laboratory metal test pieces called coupons. Next, the
contaminants are identified and the part or coupon is contaminated. Then a cleaning, rinsing and drying
protocol was followed for each situation tested. All cleaner performance evaluations were performed in
strict adherence to established protocol (preclean, clean, rinse, dry schedules) in order that the resulte
would be comparable between trial runs.
Aqueous cleaner performance was evaluated using the critical measurement of contaminant loading. For
this evaluation, three weight measurements are necessary: after baseline clean, following contamination,
and following cleaning. The differences between these weights represent the amount of contamination on
the part and the amount of contamination remaining after cleaning. From these results, the average
removal efficiency is determined. In addition, the noncritical measurement of microscopic analysis at
elevated magnification was used to assess particulates on the part or coupon prior to and after
contamination and following cleaning. The QAPP presented optically stimulated electron emission
(OSEE) and Fourier transform-infrared spectrometry (FT-IR) as possible critical measurements for the
evaluation of cleaner performance. Neither of these analytical techniques was appropriate or necessary for
the situations studied for this project. In some situations, it was necessary to analyze the effectiveness of a
cleaning chemistry or process using methods commonly accepted by the companies for whom the testing
was being conducted. These situations are described in the text
Information on the procedures used for QA, calibration and sampling can be found in Appendix A.
Parker Hannifin Corporation
Parker Hannifin Corporation manufactures motion control products for industrial and aerospace
applications. The company is headquartered in Cleveland, OH and is part of EPA's 33/50 Program. At the
Waltham, Massachusetts facility, pumps for aircraft engines are manufactured under primary SIC code
3724.
In 1992, the company began to investigate the replacement of their two vapor degreasers with an aqueous
cleaning system. The company was using CFC-113 in one degreaser and in the process of switching from
METH to 1,1,1-TCA in the other degreaser. The original idea was to replace both vapor degreasers with
one immersion cleaning system that could satisfy their highest cleanliness needs. After careful
consideration of cleaning needs and
logistics, the company decided that it
would be more effective to replace the two
vapor degreasers with three different
cleaning methods because of the different
cleaning needs. First, three pressure spray
washers were installed for frequent remote
cleaning following machining. Second,
one ultrasonic unit was installed for the
highest cleanliness needs. Third, one
immersion tank was installed for cleaning following heat treatment
Name: Parker Hannifin, Nichols Aircraft Division
Location: Waltham, MA
Primary SIC Code: 3724
Products: pumps for aircraft engines
Figures 2 and 3 show schematics of the vapor and aqueous degreasing systems. For the vapor degreaser
systems shown in Figure 2, mass balance calculations were performed. The difference between the amount
11
-------
of CFC-113 purchased and the amount of CFC-113 disposed of in the waste oil for 1992 was 20,285
pounds which was lost to the atmosphere. The losses calculated for the 1,1,1-TCA/METH vapor degreaser
were less dramatic, 496 pounds and 126 pounds respectively. The calculations for water use revealed large
quantities of water required for both degreasing processes, over 300,000 cubic feet each. As a result of
Parker Hannifin's aggressive cleaning project, they eliminated the use of chlorinated cleaning solvents over
a four year period as shown in Table 2.
Table 2. Parker's Toxics Use Reduction Act Data Pounds of Solvents Otherwise Used, 1990-1994
Chemical
CFC-1 13
1,1,1-trichloroethane
Methylene chloride
Total
1990
28290
0
11848
41138
1991
29000
0
10400
39400
1992
21000
600
1047
22647
1993
6517
1200
0
7717
1994
0
0
0
0
Pressure Spray Washers
The three ADF Systems Ltd. pressure spray washers, which operate at 750-800 psi, clean aluminum and
862013 steel parts with a 10-20 minute wash cycle followed by a hot air dry. One washer cleans aluminum
parts using WR Grace's Daraclean 282 GF. Steel parts, heavily soiled with a hydraulic oil containing
silicone from a lapping operation, are pre-washed in a mineral spirits bath for 10-15 minutes and then
cleaned in the second spray washer also using WR Grace's Daraclean 282 GF. These aqueous cleaners are
described in more detail in the Technical Evaluation Supplement section which begins on page 18. (Note:
The company plans to evaluate an aqueous-based lapping compound that could eliminate the mineral
spirits pre-wash.) The third washer, using Brulin 63-G at 8-10% concentration, cleans steel parts which do
not have the silicone contaminant. The two different detergents used in the three spray washers were the
result of a trial-and-error process that the company performed with the assistance of detergent vendors.
The parts were previously cleaned in a vapor degreaser using CFC-113.
Ultrasonic System
Both 8620 steel and aluminum parts are cleaned in the Talley ultrasonic system. These parts, contaminated
with a rust inhibitor oil, require the highest level of cleanliness in the process. The system consists of a 2
minute wash, two tap water rinses at 140F and 170F, one DI rinse at 115F, and a one minute drying cycle
at 1L50F. The detergent is Brulin 815 GD at 3% concentration. Before conversion to me ultrasonic system,
these parts were cleaned in the vapor degreaser using CFC-113.
Immersion Tank
In ithe Kleer Flo immersion tank, 8620 steel parts are cleaned on the way from a quench oil heat treat to a
nitriding14 process. The detergent in the immersion system is Oakite Inpro-Clean 2500 at an 8%
concentration. The air agitated immersion tank operates at 160F and parts are immersed for 20 minutes.
13 8620 is a number designation of the American Iron and Steel Institute and the Society of Automotive Engineers for carbon and
alloy steels. The 86xx series defines a minimum nickel-chromium-molybdenum content and the xx20 indicates the carbon
content.
14 Nitriding is a process to introduce nitrogen into the surface layer of a solid ferrous alloy by holding it at a suitable temperature
in contact with a nitrogenous material, usually ammonia or molten cyanide.
12
-------
CFC Vapor Degreaser
CFCIoss-20;285lb.
oily dirty parts
cooling water - 360,363 c.f.
CFC's-21,00011
,000 Ik
dean parts
VD#1
wastewater - 360,363 c.f.
dirrvCFCs-715lb.
1,1,1-TCA, METH Vapor Degreaser
solvent
sntloss^^
ofly, dirty parts
cooDngwate 306,995 c.£
METH-600 Ib.
TCA-1,047lb.
METH-126lb.
TCA-469to.
^clean parts
wastewater - 306,995 af.
djly solvent
METH TCA
474 Ib. 578 Ib.
Figure 2. Schematic of Parker Hannifin Vapor Degreasing Systems
13
-------
Pressure Spray Wash
water loss
oily, dirty parts
clean water
clean parts
oil skimmer
oil
dirty water
sludge
Immersion
water loss
oily, dirty parts
clean water
clean parts
oil skimmer
oil
dirty water
sludge
Ultrasonics
water loss
oily dirty parts
oil skimmer
clean parts
detergent
T
dirty water
clean water
Figure 3. Schematic of Parker Hannifin Aqueous Degreasing System
14
-------
Prior to conversion to this aqueous system, the parts were cleaned in a vapor degreaser with methylene
chloride and for a short time with 1,1,1-trichloroethane.
Technical Evaluation
Parker Hannifin's conversion to aqueous cleaning was not without challenges. The majority of the
problems were experienced in the immersion process. It is very important that the parts be free of residue
prior to the nitriding process. If a residue remains on the part and causes failure in the nitrider, production
is delayed 48 hours. Parker originally used W. R. Grace's Daraclean 282 GF in the immersion system but
experienced failures in the nitrider. Daraclean 282 GF contains silicates which were the suspected, but not
proven, cause of the failures. Parker made the switch to Oakite's Inpro-Clean 2500, a non-silicated cleaner
and at the same time added the following four steps to the cleaning process: rinsing with a hose, blowing
drying with air, glass peening,15 and drying in the oven. This made the immersion cleaning process very
labor-intensive but there were no part failures with the additional four steps. Although this procedure
worked, it was expensive due to the four labor-intensive steps added to the process as well as the use of of
Oakite Inpro-Clean 2500 at a higher concentration than recommended by the manufacturer. (Oakite
recommends 2.38% by weight Parker Hannifin was using an 8% by weight solution.)
As both the four additional labor steps and the higher concentration of cleaner were introduced into the
process at the same time, it was unclear whether they were all necessary. Elimination of any or all of them
would reduce the process cost and increase its viability as a cleaning alternative. Testing was done in
TURTs Surface Cleaning Laboratory to evaluate the necessity of each of the additional steps as well as to
determine the minimum amount of cleaner needed.
Testing in TURI's Surface Cleaning Laboratory
In order to determine which steps in the cleaning process were unnecessary, TURTs Surface Cleaning
Laboratory Staff attempted to determine the cause of part failure in the nitrider. For the first test, an actual
dirty part was obtained from Parker. Parker's cleaning process was then simulated in TURTs lab. The
dirty part was immersed in a 160F bath of 8% Oakite Inpro-Clean 2500 for 20 minutes. The part was not
rinsed and it was air dried. The dried part was examined under the microscope in order to identify any
residue. This part was compared to parts from the second test
For the second test samples of actual parts were collected from the Parker facility following each step in
the cleaning process. These samples were taken to TURTs Lab where they were examined under the
microscope. Microscopic examination of all the parts determined that the process parts did not contain
soap residue. The rinsing and drying steps did not contribute to part cleanliness. Residual surface
contamination and oil were found on the process parts indicating inefficient cleaning.
The next test was to study the effect of soap concentration on part cleanliness. This test followed TURTs
basic protocol for lab testing. Seven parts were acquired from Parker. All seven parts were precleaned in
the ultrasonics tank in a 10% by volume concentration of WR Grace's Daraclean 283, a non-silicated
cleaner. All parts were immersed in a quench oil sample obtained from Parker.
Two parts were immersion cleaned in a 2.36% by weight solution of Oakite Inpro-Clean 2500; two parts
were immersion cleaned in an 8% by weight solution of Oakite Inpro-Clean 2500; two parts were
immersion cleaned in a 20% by weight solution of Oakite Inpro-Clean 2500; and one part was not cleaned.
19 Peening refers to the mechanical working of metal by hammer blows or shot impingement (e.g., glass beads).
15
-------
The parts were not rinsed. The parts were taken to Parker Hannifin for further processing in the nitrider.
The results indicated that only the part that was not cleaned failed in the nitrider. This test suggested that
the cleaner concentration could be decreased to the manufacturer's recommendation without jeopardizing
'the nitriding process while saving money on raw material costs.
During the first months of the aqueous system, Parker was changing the bath on a monthly basis.
Operators added soap randomly to the bath as they felt necessary. This often resulted in a higher soap
concentration than needed. Parker has since instituted a policy, recommended by the manufacturer, to
perform weekly titrations on a small sample of the bath to determine alkaline content The titration results
allow the operators to add the correct amount of detergent to make up for drag-out losses without
increasing the concentration unnecessarily.
Lessons Learned
Aqueous immersion cleaning of steel and aluminum substrates following oil heat treat is a
viable option for the replacement of chlorinated solvents.
Aqueous immersion cleaning of steel and aluminum substrates prior to nitriding is a viable
option for the replacement of chlorinated solvents. However, the cleaning process conditions
must be controlled to ensure efficient cleaning.
Replacing a silicated aqueous cleaner with a non-silcated cleaner in a no rinse system solved a
residue problem.
Technical Evaluation Supplement
Parker Hannifin has done much trial-and-error work regarding the use of various aqueous cleaners on their
particular substrates and contaminants. Table 3 summarizes the substrates, contaminants, aqueous
processes, and aqueous chemistries that are effective on the four cleaning situations at Parker HanniSn.
Ta,He3. Summary of Aaueous Chemistries ,
Substrate
aluminum
steel
iiteel & aluminum
steel & aluminum
Contaminant
hydraulic oil with
silicons
non-silicone machining
oils
rust inhibiting oil
heat treat quench oil
Aqueous Process
pressure spray
pressure spray
ultrasonics
immersion
Aqueous Product
Daraclean 282 GF
Brulin 63-G
Brulin 815 GD
Oakite Inpro-Clean
2500
Aqueous Chemistry*
P
No
Yes
Yes
Yes
S
No
Yes
No
Yes
GE
No
No
No
Yes
Si
Yes
Yes
No
No
WR Grace Daraclean 282 GF is a low-foam, multi-metal cleaner. The product is specially formulated to
be non-aggressive toward aluminum and zinc alloys. Product literature claims biodegradability and the
16
-------
absence of chlorine, sulfur, phosphorous, nitrites and glycol ethers. The literature also indicates that the
product has excellent hard water tolerance. The excellent hard water tolerance and the lack of
phosphorous indicate the presence of orthosilicates as sequestering agents in this formulation. The
presence of silicates also allows for the non-aggressive behavior toward aluminum.
The product literature for Brulin 63-G states that it is a biodegradable, alkaline detergent containing
phosphates and silicates and developed for use in spray wash equipment. Brulin 63-G is stated to
effectively remove coolant residues and other oil-based soils and to contain a rust inhibitor package that
protects both steel and aluminum. It is designed to be low foaming at temperatures between 140-180F
with a recommended dilution of 3-5% in water. ;
The product literature for Brulin 815-GD states that it is an aqueous-based, biodegradable, alkaline
detergent developed for the aerospace industry for hot tank immersion cleaning and degreasing. It exhibits
superior cleaning ability on ferrous and non-ferrous metals including aluminum, titanium, and brass, as
well as plastics and composites. The recommended temperature and dilution in water are 140-180F and
5-20%. This product is reported to rinse freely, leaving no residue. The product contains phophates,
alkaline builders, detergents and inhibitors.
According to the MSDS and product literature for Oakite Inpro-clean 2500 contains tetrasodium
pyrophosphate, sodium carbonate, sodium sulfate, and sodium tetraborate as builders, diethylene glycol
butyl ether as solvent and nonylphenoxy as a polyethoxy ethanol nonionic surfactant It also contains
naphthalenesulfonic acid and sodium salt condensed. This product is non-silicated and non-caustic.
Parker found that one product, Oakite Inpro-Clean 1300, was too aggressive on the aluminum parts in the
ultrasonic system. They switched to Brulin 815 GD for their ultrasonics cleaning. Oakite Inpro-Cleaa
1300 is anon-caustic cleaner containing tetrapotassium pyrophosphate and ethoxylated secondary alcohol.
It does not contain silicates, sulfur or glycol ethers. Product literature warns that slight etching of
aluminum and zinc alloys may occur at higher temperatures or concentrations. This is due to the lack of
silicates or other inhibitors.
Market Forge
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 prior
to welding. The performance of TCA was satisfactory, but its use was discontinued because of the
labeling requirements of the Montreal Protocol. On the advice of their supplier, Market Forge switched to
an aliphatic petroleum distillate solvent (CAS 64742-88-7). To accommodate the switch, the vapor
degreaser was modified to remove the heating capabilities and add filter capacity. Besides die
modifications to the equipment, it was assumed that the
petroleum distillate solvent would be a drop-in replacement
However, as soon as the switch was made, the welders of both
the carbon steel and aluminum parts began to experience
problems.
Name: Market Forge
Location: Everett, MA
Primary SIC Code: 3499
Product* cooking steamers
Problems with Cleaning Carbon Steel
The carbon steel parts are received from the supplier coated with
East Falls Hydraulic Oil 8-32. The oil is a heavy paraffinic
petroleum distillate used as a pickling oil to prevent rusting during storage and shipping. Market Forge
17
-------
' i.
adds two petroleum oils to the carbon steel parts during processing. One oil is TRIM SOL, an aliphatic
petroleum naphtha (CAS 8002-05-9) containing sulfonates and chlorinated alkenes and reported on the
Material Safety Data Sheet to be 100% soluble in water. The^second oil is C-EBLIS Cutting Oil, a
naphthenic petroleum distillate (CAS 64742^53-6, 64742^-52-5) which is not soluble in water. After
cleaning the parts in the replacement petroleum distillate solvent, the welders report that the parts are
visibly less clean than parts cleaned with the TCA system and that the parts produce fumes when welded.
The welders have noticed an "eggshell" film on the parts and describe the parts as appearing "wet"
following cleaning with the petroleum distillate and drying.
Problems with Cleaning Aluminum
Unlike carbon steel, the aluminum parts are received "clean" with a protective coating of plastic shrink
wrap. However, during processing at Market Forge, the parts are contaminated by C-EBLIS Cutting oil
used in the stamping operation and aliphatic hydrocarbon oil used for drilling and tapping operations;.
Cleaning of these contaminants using the replacement petroleum distillate solvent proved unsuccessful
and resulted in a visible oily film which prevented proper welding. Consequently, the welders were
spraying and hand wiping with Magnuflux, a light aliphatic naphtha solvent (CAS 64742-89-8).
Technical Evaluation
The goal of the technical evaluation was to find a cleaning system that would effectively clean both the
.carbon steel and aluminum. From their analysis of the soils, the project team (TORI staff and Market
Forge personnel) decided that aqueous degreasing would be tested. Two fundamental sets of tests were
run, one to determine the most appropriate cleaning system and one to determine an effective cleaner.
Cleaner Systems Testing
In order to reduce the number and types of contaminants a potential cleaning system would have to clean,
the first course of action was to determine if it was possible to use no oil, less oil, water soluble oils, or the
same types of oils in Market Forge's processing of both metals. Unfortunately, no methods were found to
achieve these goals.
The supplier of the carbon steel indicated that the East Falls Hydraulic Oil could be cleaned with "soap
and water." Of the three remaining oils involved, the non-water-soluble C-EBLIS Cutting Oil and the
aliphatic hydrocarbon drilling and tapping oil were potentially the most difficult to clean. An attempt was
made to substitute the water-soluble TRIM SOL oil for the oil currently used in aluminum drilling and
tapping operations. When this proved unsuccessful, the aliphatic hydrocarbon oil was retained.
'The next step was to establish a baseline clean for samples of carbon steel and aluminum using TURPs
Surface Cleaning Laboratory. For testing purposes, an ultrasonics system was used to establish an
acceptable level of cleanliness for both materials. Samples of both metals were cleaned with an aqueous
cleaner, at OOF, using ultrasonic agitation for 10 minutes. A shop weld trial proved that the cleaning was
sufficient. The parts were not rinsed during this lab test for two reasons. First, the rust inhibitors in the
detergent were needed to protect the parts from rusting during storage prior to welding. Second, current
processes at the company do not require a wastewater discharge permit, so it was desirable to minimize the
use of water in the aqueous system. (Note: The company plans to explore options for extending cleaner
batlti life by filtration.)
Having established baseline clean and decided on aqueous degreasing, testing was begun to determine the
most effective alternative cleaning method. First, samples of both metals were cleaned at 130 degrees F
18
-------
for 10 minutes with an alkaline low-foam cleaner containing rust inhibitors. No agitation was used and the
parts were not rinsed. A shop weld trial proved that the welding was unsuccessful because fumes, beyond
normal welding fumes, were emitted. The results of this test, combined with the weld tests on baseline
clean metal, established what acceptable and unacceptable levels of cleanliness were and also established
the effects of poorly cleaned metal on the welding process. These combined results led to the development
of a lab test used to determine the acceptability of various immersion and pressure spray cleaning tesits.
The lab test simulated the welding process by subjecting sample plates of metal to a flame from an oxy-
propane torch while two observers watched for fumes. A visible difference between the acceptable and
unacceptable samples was seen.
The results of the testing, by company personnel visual inspection and company-approved weld test,,
indicated that both immersion with agitation and pressure spray systems cleaned the metal effectively. As
Market Forge did not have a wastewater discharge permit, the project team decided on a pressure spray
aqueous system because less water was required compared to the immersion system.
Testing Efficiency of Different Cleaners
Having decided on a pressure spray system, the next objective was to determine the cleaning efficiencies of
various aqueous chemistries. Tests were performed on Market Forge carbon steel parts, cut to 2" x 1"
pieces. Initially, a high pressure spray washer (1000 psi) was used for this evaluation. Overall results
showed that the high pressure spray system could not be used when testing the differences in efficiencies
of cleaners because the cleaning ability of the high pressures masked the small differences between the
cleaners.
Three different cleaners were tested in TURTs low pressure (-20 psi) spray washer. The cleaners were
chosen based on compatibility with metals and contaminants, ability to be used in a pressure spray system,
and previous success in similar applications. The three cleaners were WR Grace Daraclean 283 (5% by
volume), Brulin Corporation 815-GD (5% by volume) and Oakite Products Ihpro-Clean 2500 (54.49
g/gallon - company recommends 2.38% by volume). There were nine samples for two trials (two controls).
and eight samples for the third trial (one control).
Part samples were precleaned in the ultrasonics tank and weights were taken. The samples were then
contaminated by wiping them with East Falls Hydraulic Oil 8-32 and allowed to age for two hours. All
testing was done in accordance with the Quality Assurance Project Plan. The Plan was modified to more
closely represent the actual situation at Market Forge by changing the sample aging time following
contamination from 24 hours to 2 hour. The weight of contaminant removed was then determined Iqr
weighing the samples before and after cleaning. A removal efficiency was then calculated. The raw data
for the testing results are hi Appendix B. Table 4 provides a summary of the data.
Cleaner
Daraclean 283
Brulin 815-GD
Inpro-Clean 2500
Average Removal Efficiency
(%)
96.231
92.382 ;
91.566
Standard Deviation
(%)
1.493
2.727
2343
19
-------
Vapor Degreaser
TCA toss-4,195 b.
dirty parts
clean TCA - 7.1451
clean parts
dirty TCA - 2,950 b.
ol
Petroleum Hydrocarbons
petroleum hydrocarbon loss - 6,313 Ib.
dirty parts
petroleum
hydrocarbons
9.765 Ib.
.clean parts
dirty petroleum hydrocarbons
jUKMb.
ol
Aqueous Pressure Spray Wash
water loss
dirty parts
clean water
clean parts
filter
• dirty filters
ol
dirty wa
figure 4. Market Forge Metal Cleaning System
20
-------
Since the cleanliness of the carbon steel parts was the most immediate need, the testing was first performed
on those parts. As is shown in Table 4, the Daracleah 283 gave the best results and was chosen by the
project team. The carbon steel cleaned with Daraclean 283 passed visual inspection and shop weld tests.
Because Market Forge does not test for adequate paint adherence using any of the common tests, the paint
adherence test performed here was simply a visual inspection of paint adherence immediately following
paint application and again four weeks following application. Subsequent cleaning trials performed on the
aluminum parts indicated that the Daraclean 283 was acceptable for aluminum as well. The aluminum
parts were visually inspected, shop weld tested, and also tested for paint adherence. The aluminum passed
all these tests and, although stained by the process, it was not etched. Staining is not a problem for this
application.
During initial site visits, the project team also discussed standard operating procedures. Included in this
discussion were the issues of parts configuration during cleaning and parts inventory control. The current
parts configuration procedure for the degreaser requires that parts do not cover one another thus preventing
cleaning; however this procedure is not always followed. Market Forge is implementing a more aggressive
education program to address this issue. In addition, the company is exploring methods of more efficient
materials movement Currently, cleaned parts may be stored for months before use. Storage conditions of
the dirty and clean parts were also discussed. Current storage conditions add contaminants to the dirty
parts and do not adequately protect the cleaned parts from leaking roofs and other shop dirt Improvements
in these areas will be necessary for the success of any alternate cleaning system.
Based on the information obtained from this project, Market Forge purchased an American Metal Wash
pressure spray washer. (See Figure 4 for a schematic representation of the vapor degreaser, the naphtha
solvent system and the pressure spray washer.) The unit was recently installed and has been operating
effectively for three months. The viability of close looping the aqueous cleaning system with an
ultrafiltration unit was researched. Two successful closed loop aqueous cleaning projects are described in
Appendix C.
QA Results \
QA tests determined that the analytical balance used here had a precision
of 0.1 mg and an accuracy of 0.3 mg. In the performance tests, the
contaminant loading ranged from 16.8 to 74.2 mg. Using the smallest
loading, the maximum error in precision was 0.6% and the maximum
error in accuracy was 1.8%. (See the equations in the box.) These
numbers can be compared to the experimental results summarized in
Table 5. Since the standard deviations of the removal efficiencies ranged
from 1.5-2.3%, it can be concluded that most of this variability was due to
the actual'differences in removal efficiency from test to test, rather than
imprecision in the measurement Again comparing this number to Table 5, average experimental removal
efficiencies for the three cleaners were 91.6%, 92.4%, and 96.2%. The difference in average cleaning
efficiency between the best cleaner (Daraclean 283) and the second best cleaner (Brulin 815-GD) was
3.8%; since this is more than twice the maximum accuracy error of 1.8%, it can be stated with confidence
that Daraclean 283 had the best removal efficiency under the conditions tested.
0.1
16.8
0.3
16.8
x 100 = 0.6%
x 100 = 1.8%
21
-------
Lessons Learned
"Drop-in" petroleum solvents are not always effective alternatives to chlorinated solvents for
* f **- .h;-' t ^ J ,!.*£:• :*,?•.
cleaning prior to welding operations as evidenced at this test facility-
Pressure spray aqueous cleaning can effectively remove pickling oil from carbon steel and
aluminum parts.
A no-rinse aqueous degreasing process is a viable alternative prior to painting for aluminum
parts.
Company A
Company A is a job-shop electroplating company located in i
Massachusetts. By the nature of the job-shop business, Company Name: Company A
A cannot always predict what types of metals it will have to clean Location: Massachusetts
and thus requires a flexible cleaning system, capable of cleaning Primary SIC Code: 3471
many different substrates. Currently the company cleans all their Products: electroplated parts
parts in a vapor degreaser using TCE. In 1993, Company A used
8,600 pounds of TCE; in 1994 they used 11,152 pounds. Figure
5 shows a mass balance of the TCE vapor degreaser using 1994
data. Calculations to obtain the mass balance revealed that almost 94% (or 10,466 pounds) of the TCE in
the system is lost to the atmosphere. There is no cooling on the degreaser. As experienced by other
companies, Company A has seen an increase in the need for cleaning because their customers, who used to
supply parts that had been cleaned with CFC's, are cleaning less due to regulations on ozone depleting
chemicals. As a result, Company A is very interested in evaluating cleaning alternatives to decrease their
use of TCE.
TCE loss-10,456 to.
dirty ports
TC£-1U52lb.
cteon ports
dirtvT
TCE-686 !b.
Figure 5. Company A TCE Vapor Degreaser
22
-------
Ninety percent of the base metals cleaned at Company A are: carbon steel, stainless steel (303,316 L, 400,
416,410,174PH, 155PH), aluminum (6061, 2024, 356,7075) and copper (brass and bronze). The
remaining 10% of the base metals cleaned are: titanium, zinc diecast, aluminum diecast, plastics and other
metals depending on the customer.
Currently, all parts are cleaned in the TCE degreaser. Subsequent processing steps, considered to be
surface preparation steps by the company, may include electrocleaning, acid cleaning or caustic cleaning
depending on the surface required. A diagram of this process is shown in Figure 6. These subsequent
processing steps provide opportunities for performing some of the cleaning function currently performed
by the degreaser. The electroclean bath contains a silicated cleaner, Rokleen 123 from McGean-Rohco at a
6 oz/gallon concentration and a temperature of 150F. The solution is changed every three or four months.
The acid clean bath contains-hot sulfuric acid. All aluminum parts are soak-cleaned in a borax (caustic)
solution.
parts in
Vapor Deg re a set
Electroclean
parts
out _
Acid Clean
part
out ,
Soak Clean
parts
out _
Figure 6. Company A Cleaning and Surface Preparation Process
Due to the relative low cost and effectiveness of TCE for all of their cleaning needs, Company A is
apprehensive about investing in an unproven technology that may not be effective on all substrates. Faced
with similar decisions, other plating companies have phased in aqueous cleaning alternatives for specific
substrate groups. Once they developed confidence in aqueous cleaning, they were able to expand its use
and eliminate the use of chlorinated solvents. Presently, Massachusetts plating companies are at various
stages of converting to new cleaning technologies. The preferred cleaning alternative in the plating
industry has been aqueous cleaning.
Identification of Options
Due to the variety of substrates and contaminants that require cleaning at Company A, it would be difficult
to define an aqueous cleaning chemistry and process that would work for all the possible variations •. Due
23
-------
to die sensitivities of dieir wastewater treatment system, Company A is not able to consider petroleum-
based solvents, long chain organics or aqueous chemistries with silicates. Their wastewater treatment
system is able to handle die once-every-tiiree-or-four-mondis dump of the Rokleen 123 bath. However, this
badi dump is not easy for die wastewater sytern to procesiTandthe company does not want to add more of
this type of wastewater to its treatment system.
Depending on die aqueous chemistry, heated rinse tanks widi agitation may be available for use. The
company also has drying capabilities. The company currently has a small sand blasting unit which is used
for surface preparation on specific materials. In addition, die operators are skilled and familiar with
different processes required for different metals.
The goal of diis project was to identify a cost effective cleaning system mat will clean all possible
substrates and contaminants, or selected substrates and contaminants, with die minimum use of listed
substances. The cleaning system must also be compatible widi die waste water treatment system. In a
brainstorming session widi company representatives, die following options were identified for further
evaluation.
* media blasting - sodium bicarbonate, plastic, carbon dioxide
>• ultrasonic aqueous
»• "closed" vapor degreasing
>• upgrading existing vapor degreaser
> Advanced Vapor Degreasing (AVD™) system
»• supercritical carbon dioxide
Evaluation of Options
The six options identified were screened for potential applicability. A description and outline of the
technical evaluation is provided for each option. A summary table (Table 5) of results follows the
descriptions. Options with promise were further evaluated in the financial and substitution analysis
sections.
Media Blasting
Sodium Bicarbonate—Abrasive blasting with sodium bicarbonate was evaluated as a cleaning step for
aluminum parts. Sodium bicarbonate is a relatively new media for the blasting process. It has been used
effectively to strip paint in a number of applications. The waste resulting from this process is dirty (oily)
sodium bicarbonate which would most likely be nonhazardous waste based on the experience of the
equipment salesman. The waste from this trial was not tested to determine whether it was hazardous.
The trial was performed at the Dawson-McDonald company located in Wilmington, MA- Dawson-
McDonald distributes blasting equipment manufactured by Empire Abrasive Equipment Corporation in
Laughorne, PA. The sodium bicarbonate was delivered by suction feed at 50 psi in a media blast cabinet
Following blasting the aluminum part looked very clean, but had a dull finish. The part was returned to
the company for inspection and further processing. The company representative was satisfied with the .
level of cleanliness of the part but was not satisfied with the dull finish. While a shiny appearance of the
finish prior to plating is not an actual requirement, the company did not want to risk possible unacceptable
plating. Therefore the part was buffed and cleaned in the TCE degreaser prior to plating.
24
-------
Empire Abrasive Equipment Corporation sells tumble blast, pass through automation and rotary table
equipment. The availability of space may be a problem for the pass through automation equipment For
the rotary table equipment, an operator stands outside the cabinet and replaces dirty parts for clean parts as
appropriate.
Plastic—Media blasting using plastic media was evaluated as a cleaning step for aluminum parts. Plastic
media w.as chosen for this evaluation because it will not harm the soft aluminum surface. The medium
evaluated was Polyplus from U.S. Technology Corporation in Putnum, CT. The plastic particles are!
irregularly shaped with sharp edges for effective cutting action. The hardness of the particles on the Moh
scale is 3.5. The medium has a density of 1.5 g/cm3. The mesh size of the media tested was 30-40 mesh
(0.023-0.015 in.).
The medium was expelled via a 25 psi pressurized air stream. Pressurized air was rased as a final step to
blow off the media. The media was filtered through a cartridge filter. The waste that is produced in this
process is dirty (oily) plastic media most likely be nonhazardous waste depending on actual test result from
a sample of the waste.
The trial was performed at the Dawson-McDonald company located in Wilmington, MA. The media blast
cabinet used was manufactured by Empire Abrasive Equipment Corporation in Langhorne, PA. Following
blasting, the aluminum part looked very clean and had a shiny finish. The part was returned to the
company for inspection and further processing. The company representative was satisfied with the level of
cleanliness of the part and the part was satisfactorily plated with no further cleaning or buffing.
Carbon dioxide—Fragmented carbon dioxide blasting was examined for the cleaning of all parts at
Company A. A trial was performed on three aluminum pieces at Environmental Alternatives, Inc. ia
Westmoreland, NH. Environmental Alternatives, Inc. offers design, sales, and training expertise. The
parts tested were adequately cleaned. However, the parts were deformed as a result of the cleaning process
to levels that were unacceptable to the company.
Ultrasonics
For this application, an ultrasonic cleaning process was evaluated as a cleaning step prior to surface
preparation for the aluminum pieces that comprise 25% of the total cleaning needs.
A technical evaluation was performed at TURTs Surface Cleaning Laboratory. The aluminum part,
contaminated with various oils and machining fluids, was obtained from the company. A neutral cleaner,
WR Grace's Daraclean 235 (pH 7.1) was chosen to give a wide range of substrate compatibility and to
ensure that no etching would take place on the aluminum part. This product also contains no silicates. A
7% by volume solution of the Daraclean 235 was used. The part was immersed in a 140F ultrasonics bath
(6 transducers, 40 kHz, 500 watt) for 10 min. It was rinsed in 148F tap water for 2 min and in 116F
deionized water for 2 nun. The part was dried using air knives at room temperature. The part was
returned to the company for inspection and plating. By visual inspection the part was clean. It was then
plated successfully with no additional cleaning.
Supercritical Carbon Dioxide
This technology was considered for its theoretical technical feasibility, noting its current state of
development Discussions were conducted with a vendor of the equipment and with an academic
researcher in the field. According to these experts, supercritical carbon dioxide has been proven to clean
precision parts and works well on all metal parts that can be subjected to high pressures and temperatures.
25
-------
For the cleaning needs at Company A, it is very likely that supercritical CO2 technology could effectively
clean all parts prior to surface preparation. However, based on the capital cost requirement and the fact
that Company A was not interested in this technology, no technical evaluation was performed. This
.technology may eventually become cost effective. More; information on this technology can be found in
EPA's Guide to Cleaner Technology: Alternatives to Chlorinated Solvents for Cleaning and Degreasing.
New Vapor Degreaser
The degreaser currently used by the company is an older model degreaser that allowed large evaporative
losses to the atmosphere. The company representatives wanted to explore the purchase of a new degreaser.
Newer model vapor degreasers, still using TCE or other solvents, incorporate features such as additional
freeboard area, improved chillers, and cover panels that are designed to prevent excessive solvent losses to
the atmosphere. If the new degreaser was supplemented with operator training the use of TCE would
decrease significantly from current use. No technical evaluation was necessary due to the fact that this is a
proven technology for this application.
Retrofit Existing Vapor Degreaser
The company representatives also wanted to evaluate the option of retrofitting their existing vapor
degreaser by improving the cooling capacity to decrease evaporative loss of solvent This option involves
increasing die freeboard area within the current degreaser and adding an associated freeboard chiller.. In
this manner, more of the TCE vapor will condense on the degreaser walls and flow back into the sump
rather than escaping to the atmosphere. No technical evaluation was necessary due to the fact mat this is a
proven technology for this application.
Implement AVD™ System
The company had read about the AVD™ system in a trade journal and was interested in pursuing its;
applicability to their needs. The AVD™ system, developed by Petroferm, lac. uses a cosolvent system:
one for cleaning, which leaves an oily residue on the part, and one for rinsing and drying, a perfluorinated
compound. The process uses a retrofitted two sump vapor degreaser or new equipment The AVD™ unit
contains two compartments to hold each of the solvents, and otherwise functions in a manner similar to
other vapor degreasers. This type of unit is most beneficial when cleaning small, intricate parts such as
electrical connectors and jewelry.
The two, non-miscible, materials are a solvating agent and a rinsing agent The solvating agent,
manufactured by Petroferm, Inc., is an ester based material with a flash point of over 200F. The rinsing
agent is a perfluorocarbon material manufactured by 3M. It has no flash point In the wash sump, title two
materials are combined in equal proportions by weight and the bath is highly agitated The parts are
immersed in the mixture, which is heated to 133F, for 2-5 minutes. In the rinse sump, the parts are
immersed in 100% perfluorocarbon which is not heated. Parts emerge residue free and dry.
EPA's current position on perfluorocarbons is that without more complete knowledge of their global
warming impacts, they may only be used as a substitute for ozone depleting solvent cleaners where mo
other substitutes exist16 Based on this position, cleaning of basic metal parts is unacceptable because
alternative cleaning processes are available. Although a direct technical evaluation was not performed, all
16 EPA Memorandum from Nina Bonnelycke, Stratospheric Protection Division, "Uses of Perfluorocarbons in Industrial
Cleaning", 1/6/93.
26
-------
reports and available data about the technology suggest that it would be appropriate for the materials and
contaminants at Company A.
Lessons Learned
Plating companies experienced an increased demand for cleaning as regulations on ozone
depleting chemicals discouraged their customers from cleaning parts.
There are no simple, drop-in cleaning alternatives for job shops making the gradual phasing
out of chlorinated solvents a preferred option.
Because TCE is not heavily regulated, the motivation for replacing TCE as a degreasing
solvent is not as great as the motivation for replacing the ozone depletors.
27
-------
I
§
"2
ll
II
8 8
11
Z 2
1
S
I
g
£
s
W
•§1
"
-a
3
S
I
§
g
•
I
tt.
-------
si
u ,2
jl
•§§
IS
8
I=H-
a u —T
,1 EX, ed
sf'§
o-ll
1.
05 S
a S.
»
e « ^ o
O M — o
I
0.5 o
US
i|i
8 Is
•» •£ "3
51 |
11
"3 2
I J &
S-C «
5 is
*J
iiiH
S o c e a
g^_ *M • *•< O Co
II If I
§p|i
1^11"
§"3 "9 * S *
(3 .S I 2 1 °
III111ill
a-
-------
Chapter 4
Investment Analysis
Introduction
In addition to the outcome of technical evaluations, major deciding factor when considering alternatives to
current processes is the result of an investment analysis. Typically companies attempt to predict the
profitability of their investments by performing calculations using initial investment costs and annual
savings generated by new equipment. Traditional financial analysis, however, often includes only the costs
directly 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 (TCA) methodology used
in this project is an innovative evaluative tool that examines many other important costs associated with an
investment including such things as staff time for environmental reporting, waste management costs, and
permitting fees.
The Total Cost Assessment tool was used in three different ways in the four analyses in this section. The
first two analyses were performed on the cleaning situations at Parker Hannifin. The company had already
implemented aqueous cleaning to replace chlorinated solvent vapor degreasing. In the first analysis, TCA
was used to take a retrospective look at the investment In the second analysis, a TCA was compared to the
companies' own financial analysis of the project. In the third analysis, TCA was applied to the Market
Forge case to support the degreasing project as it competed with other projects for capital. An analysis was
also performed on the intermediate, naphtha solvent system to see how mis system compared to the
aqueous alternative. For the fourth and final analysis, TCA was used as a decision making tool to help
decide among technically feasible alternatives at Company A.
Each company was in a different state of implementing the cleaning alternatives and the data for each
subsequent analysis became less precise the further the project was from implementation. The use of TCA
as a piece of the decision making process for each situation is discussed in the conclusion of this section.
(The use of pay-back period and net present value as financial indicators is presented in Appendix D.)
Total Cost Assessment
Total cost assessment is an innovative analytical approach for evaluating and comparing the full costs of
production related investments. It is innovative because all the costs associated with a production
investment are included in the assessment, rather than only including the costs directly associated with
production, such as labor and capital. Costs often missing in simple production related investment
evaluations include insurance, waste disposal, compliance with environmental regulations, utilities, and
occupational safety and health training. Businesses typically group many of these costs in overhead
accounts or non-production departments such as environmental and occupational safety and health.
Many business accounting systems often do not track environmental costs in a manner in which they can
be allocated to the products and processes responsible for producing those costs. As a result of this, many
30
-------
businesses make investment decisions that are based on insufficient information and have a tendency to
ignore the environmental impact of an investment.
The financial impact of environmental costs is increasing for several reasons. In recent years insurance
companies have increased the premiums for businesses that use toxic chemicals because of the hazards
posed to workers19. Additional regulations, fines for emissions, and fees for the use of toxic chemicals
have resulted in increasing costs of compliance. As a result environmental costs are significant factors in
investment analyses.
Total cost assessment is used in this report to assess and compare all costs associated with using toxic
chemicals and alternative cleaning systems. Critical elements in a total cost assessment include
»• expanded cost inventory
»• direct allocation of costs to processes and products
*• extended time horizon
* use of long-term financial indicators
These four elements help demonstrate the true costs of production to a firm, the net benefits, or costs, of
pollution prevention programs, and how prevention-oriented investments compete for investment capital
within company-defined standards of profitability.
It should be noted that the analyses here are limited to internal costs (i.e., those with measurable financial
consequences to the company). No attempt was made to estimate the costs to the community surrounding
the manufacturing facility or to society at large. By definition, full cost accounting would include these
costs, such as health effects to the surrounding community from the use of hazardous substances and ozone
depletion from the use of chlorinated solvents.
Data Collection
The data for this study were taken or derived from company purchase orders, waste manifests, chemical
inventories, maintenance records, and catalog prices. Indirect costs were found through labor rates, fees
and taxes, and time required for compliance with applicable environmental regulations. Helpful resources
included environmental managers, operating engineers and accountants within the subject companies,
vendors of alternative cleaning systems and cleaning agents, TURTs Technology Transfer Center,
representatives of state agencies, representatives of reclaimers and waste haulers, and other case studies of
total cost assessment '
The biggest challenge to providing an accurate assessment of all quantifiable costs associated with total
cost assessment was data collection. Costs were not often available within companies and other data
sources were used. Collection of these data is often very difficult and time-consuming. These costs may
be significant and demonstrate the importance of accuracy in cost tracking. When assumptions on costs
were made, plant personnel and specialists were consulted. Explanations for missing date are given in the
text
" Dyer, JLA. and K. Mulholland," Toxic Air Emissions: What is the Full Cost to Your Business?", Chemical Engineering,
February 1994.
31
-------
Parker Hannifin switched to aqueous cleaning prior to in 1993. The 1994 costs were used rather than 1993
coste for two reasons. First, because the data was collected in 1994, actual costs could be used rather than
estimations of 1993 costs. Second, because of the ever increasing cost of chlorinated solvents, using 1994
data provided the most up-to-date analysis (and outcome) possible. It must be noted that the use of 1994
data results in a more positive outcome for the aqueous system than when Parker Hannifin actually made
the decision to invest
Parker Hannifin: Analysis One
Background
The first analysis was performed on Parker Hannifin's aqueous immersion cleaning process. The company
uses a discount rate of 16% and a labor rate of $16.05 per hour. Parker Hannifin has assigned this project
an economic lifetime of seven years.
Cleaning Operations
Prior to the use of aqueous cleaning systems, the company used two vapor degreasers for cleaning. The
company made the switch to aqueous cleaning in 1993. This analysis addresses the replacement of one
vapor degreaser by an immersion tank; the replacement of the second vapor degreaser is addressed iii the
second analysis. An immersion tank was selected to replace the vapor degreaser in which 1,1,1-
trichloroethane and methylene chloride were used.
Capital Costs
Prior to the installation of the immersion tank, the vapor degreaser had to be cleaned and disposed.
Disposal cost of the vapor degreaser was estimated at $ 1,000.20 The clean out resulted in one drum of
reclaimed 1,1,1-uichloroethane and one drum of reclaimed methylene chloride. Using 1994 prices for
reclaimed solvents, this would result in a $50 benefit Therefore the total cost for disposal of the vapor
degreaser was $950.
Table 6. Parker Hannifin Analysis One - Capital Costs
Capital Costs
Equipment purchase
Disposal of old process
Initial permits
Building/process changes
Vapor
Degreaser
NA
$950
NA
NA
Total Capital Costs
Immersion Tank
$20,000
NA
0
included in purchase
$20,950
The company purchased an immersion tank, model PW200, from Kleer-Flo Cleaning. The tank, with a
loading capacity of 200 pounds, is used to clean steel parts. It contains an oil skimmer and an upgraded
filter system. The costs for purchasing, modifying and installing the equipment were $20,000. The capital
costs are summarized in Table 6.
20 Capital Appropriations Request by Parker Hannifin.
32
-------
Operating Costs
The operating costs are summarized in Table 7.
OPERATING COSTS
Chemical Purchases
1,1,1-TCA*
Methylene chloride
Oakite Inpro Clean
Waste management
Safety training/equip
Insurance
Fees
Filing paperwork time
Annual permitting
Maintenance
labor
materials
Production costs
Utilities
elect
water
gas/steam
Total annual operating costs*
Incremental cash flow*
Vapor Degreaser
$918
$691
NA
$15,938
0
0
0
(indefinable
(indefinable
! included in materials
$1,010
0
$2,652
$4,938
0
$26,147
$23,455
Immersion Tank
NA
NA
$696
$10
0
0
0
(indefinable
undefinable
$201
$1,000
0
$780
$5
0
$2,692
•These figures are for the first year of operation. The second year costs for 1,1,1-TCA, total annual operating costs and
incremental cash flow are $978, $31,290, $26,377. In the remaining years these figures will go up as the excise tax on 1,1,1-
TCA increases by $0.045/lb/yr.
Chemicals and Wastes
The solvents used in the vapor degreaser were methylene chloride and 1,1,1-trichloiroethane. The total
consumption of methylene chloride in 1992 was 1,047 pounds. At the 1994 price of $0.66 per pound, this
would cost $691.02.21 The 1992 consumption of 1,1,1 trichloroethane was 600 pounds. At the 1994 price
of $1.53 per pound,22 the cost for 1,1,1 trichloroethane was $918. The total cost of 1,1,1 teichloroethane
and methylene chloride was $ 1,609 per year.
51 DOW Chemicals, market price quote, July 1994. ;
a Ashland Chemical Corporation, market price quote, July 1994. This price includes the excise tax on ozone depleting
chemicals which is $0.435/lb for 1,1,1-trichloroethane. The tax will go up to $0.535/lb in 1995 and will increase by $0.045/lb
each year thereafter. This tax increase is considered in the financial analysis.
33
-------
The cleaning product currently used in the immersion tank is Oakite Inpro Clean 2500. The cleaner is
replaced every month whether or not there is any indication that a bath change is needed. No detergent is
added between bath changes. For each batch, 40 pounds of cleaner is used resulting in an annual
consumption of 480 pounds. At a cost of $ 1.45 per pound, the annual cost of cleaner is $696.
The wastewater generated from the cooling water for the vapor degreaser was 306,995 cubic feet per year.
The sewer cost for a cubic foot of water in the City of Waltham is $0.0283. The total sewer cost of cooling
water is $8,688. The wastewater resulting from the monthly changeover of the immersion tank is
evaporated therefore no sewer costs are associated with this cleaning process.
The disposal costs for two types of hazardous waste can be attributed to the vapor degreasen contaminated
solvent and contaminated oil. One drum of contaminated 1,1,1 trichloroethane and 1 drum of
contaminated methylene chloride were generated in 1992. These drums were sent to a reclaimer. The
yield of trichloroethane was 93%,which resulted in a credit of $55 for one drum.23 The yield of methylene
chloride was 77% which resulted in a credit of $15.24 It was common practice for the machine operators to
have containers of the chlorinated solvents at their work stations for .periodic cleaning needs. As a result,
the waste oil from these machines was contaminated with the solvent and required a higher price for
disposal than if the oil had not been contaminated. In 1992, the company had to dispose of 54 drums of
1,1,1 trichloroethane-contaminated oil, at a cost of $230 per drum, or $ 12.420.25 The cost per drum of non-
contaminated oil is $95. The difference in disposal cost of the waste oil is $7,290. This cost can be
attributed to the vapor degreasing system. Using the aqueous cleaning system, no solvent is available for
use by the operators. As the practice was one of convenience more than necessity, no new cleaning
practice was undertaken for periodic cleaning needs. The total annual waste management costs were:
$ 15,938 per year ($8,688 + $7,290 - $55 + $ 15). Costs for transportation of hazardous wastes are not
included in this analysis.
The wastes created by the immersion process are oils that are skimmed off and filters that need to be
replaced. The total disposal cost of oil skimmed from all of the company's cleaning systems was divided
over the separate systems by using the number of parts each system cleans. The total cost for hazardous
waste disposal for the immersion tank is $9.68. It was impossible to account for the individual cost of
filters and residuals from the evaporator for this degreaser. The filters are disposed of along with other
wastes from other processes at the facility. The wastewater from the immersion process is a negligible
amount of the waste that is processed in the evaporator.
Regulatory Costs
The company did not have to pay fees under the Toxics Use Reduction Act (TURA) on methylene chloride
or 1,1,1 trichloroethane because neither use exceeded 10,000 pounds. TURA fees must be paid when the
consumption of a listed chemical that is 'otherwise used' exceeds 10,000 pounds. Likewise, the company
did not have to report under the Superfund Amendments and Reauthorization Act (SARA) Title HI
because the amount used did not meet the threshold. Due to the large quantity of water used in the vapor
degreasing system, there would be some cost associated with the permitting and sampling requirements.
23 General Chemical Corporation, Framingham, MA, market price quote, August 1994.
24 General Chemical Corporation, Framingham, MA, market price quote, August 1994.
25 Laidlaw Environmental Corporation, North Andover, MA, August, 1994. This price is an estimation; the exact price is
determined after a sample is analyzed.
34
-------
However, the company was unable to provide any estimation of the time associated with these duties. For
the purposes of this analysis, then, it was assumed that there was no difference in regulatory/permitting
costs between the two systems although one would assume that the immersion tank would have a lower
cost associated with it than the vapor degreaser.
Production and Maintenance Costs
It is difficult to account for differences between the systems with regard to production costs. Neither the
vapor degreaser nor the aqueous cleaning systems require an operator because the cleaning activities are
integrated into the production process. The parts in the immersion tank have to be cleaned for a longer
period of time, but this has not resulted in a loss of production because the workers perform other activities
while the parts are being cleaned.
Based on information supplied by the company, the maintenance costs for the vapor degreaser were
calculated at $1,010 per year (using the company's 50 week year). The two filters on the immersion tank
cost $10 each and are replaced every week, or $ 1,000 per year. Maintenance on the immersion tank is
estimated at a quarter of an hour per week; this is 12.5 hours per year times $16.05 per hour labor, totaling
$201 per year.
Utility Costs
The annual cooling water consumption of the vapor degreaser was 306,695 cubic feet The cost for a cubic
foot of water in the City of Waltham is $0.0161. The total cost of cooling water is $4,938. The water
consumption in the immersion tank is calculated as follows: 200 gallons/change of tank times 12 changes
per year or 2400 gallons per year. The total cost of this water is $5.17. The cost of electricity for the vapor
degreaser and the immersion tank are, respectively, $2,652 (20,400 KW * $0.13 $/KW)26-CT and $7i80.
The hourly electricity consumption of both systems is the same but the vapor degreaser operated 68
hrs/week and the immersion tank operated 20 hrs/week. (Although the immersion process requires that the
parts are cleaned for a longer time than was required by the degreaser, the immersion tank has a larger
capacity.) Because the wastewater from the immersion process is a negligible amount of the waste that is
processed in the evaporator, the energy costs of the evaporator that could be attributed to this process were
assumed negligible and were not calculated. ;
Project Outcome
The net present value of the investment is $40,940. (See Table 8.) An investment is considered profitable
if the NPV is positive; the higher the value, the more profitable the investment The payback period for the
investment is 10.8 months before taxes (i.e., the cost of the capital investment was recovered in 10.8
months of operation.) This is considerably less than the company's required payback period of 2 years.
Often times the operating period of equipment is longer than the depreciation period. This means the
investment is more profitable because it continues to generate savings beyond the seventh year. For
example, if the equipment operates for ten years, the after tax cash flow in each of the last three years
would be approximately $16,000 (no depreciation tax shield). If this after tax cash flow is discounted over
years 8,9 and 10 of the investment, the net present value of the investment would be over $60,000.
26 Quotes from manufacturers of immersion and vapor degreasing systems, August 1994.
17 City of Waltham representative quote, August 1994.
35
-------
.•-'•' • . "' "' :~
Financial Indicators
Incremental cash flow*
- Depreciation (T^year straight-line)*
t
Taxable income*
- Income tax (40%)*
Net income*
•(•Depreciation
After tax cash flow*
Present value
- Total capital cost
Net present value
Benefits / cost ratio
Payback period*
Vatae
$23,455
$2,993
$20,462
$8,185
$12,277
$2,993
$15,270
$61,890
$20,950
$40,940
1.95
10.8 months
•These values are for the first year of the investment Subsequent year's figures, except
for payback, would be higher because the excise tax on 1,1,1-TCA is increasing.
Lessons Learned
Aqueous degreasing used less water than vapor degreasing because of the large cooling
requirements of the vapor degreaser.
Costs for the disposal of waste oil decreased dramatically with die aqueous system because
operators no longer had solvents available for cleaning equipment, hence no contaminated
waste oil was generated.
Electricity costs decreased with the aqueous system because of the larger load capacity.
Results obtained using P2/Finance Software, Tellus Institute, Boston MA, 1995.
36
-------
Parker Hannifin: Analysis Two
Background
The second analysis was performed on Parker Hannifin's replacement of the CFC-113 vapor degreaser.
The company uses a discount rate of 16% and a labor rate of $16.05 per hour. Parker Hannifin has
assigned this project an economic lifetime of seven years.
Cleaning operations
Prior to installing the aqueous cleaning systems the company used a vapor degreaser with Freon TF
(CFC-113). The production of this ozone depleting chemical was phased out by January 1995. Freon is
currently no longer being produced but small quantities of recycled material remain available. Although
the company switched to aqueous cleaning in 1992, it is assumed for this analysis that the investment was
made in 1994. This is done so the financial impact of the investment can be analyzed using actual costs
rather than using estimated costs.
The company decided to replace the vapor degreaser with one ultrasonic cleaning system and three spray
washers. These two different aqueous cleaning systems were chosen because the demands for cleanliness
of the parts differ hi different stages of the production line. The spray washers do not clean as effectively
as the ultrasonics system but they are less expensive. This system has two important advantages: (1) parts
can be cleaned at different locations so there is little loss of time, and (2) the initial investment cost v/as
lower than buying one large system to satisfy to highest need for cleanliness.
Capital Costs
Before the new cleaning system could be installed the vapor degreaser had to be cleaned and disposed.
The cleaning resulted in 330 gallons (6 drums) of Freon-contaminated oil. The disposal cost of this oil was
$230 per drum, $1,380 total.29 The disposal cost of the vapor degreaser was estimated at $1,00030. The
total cost for the clean out of the old cleaning system was $2,380.
The company purchased a Tally ultrasonic cleaning system with one wash tank, two tap water rinses, one
deionized water rinse and a drying chamber. The system cleans both aluminum and steel parts whose main
contaminant is rust inhibitor oil. The total cost for this investment was $33,964. Equipment installation
and modification are included in the purchase price.
The company bought three ADF spray washers at a cost of $10,043.50 each. Two of the spray washers
clean steel parts and the third cleans aluminum parts. The cleaning cycle includes a hot-air dry. Some
parts are pre-washed in a mineral spirits bath; the costs of the pre-wash are not included in this analysis as
they did not change by switching to the aqueous system. Adaptation and installation costs were included
in the purchase price of the equipment Total investment cost for the spray washers was $30,131. The
capital costs are summarized in Table 9.
59 Laidlaw Environmental Corporation, North Andover, MA, August, 1994. This price is an estimation; the exact price is
determined after a sample is analyzed.
30 Capital Appropriations Request by Parker Hannifin.
37
-------
Table 9. Parker Hannifin Analysis Two -Capital Costs -'' ••'.
Capital Costs
Equipment purchase
Disposal of old process
Initial permits
Building/process changes
Total Capital Costs
Vapor Degreaser
NA
$2,380
NA
NA
Ultrasonic Tank
$33,964
NA
0
included in purchase
Spray Washers
$30,131
NA
0
included in purchase
$66,475
Operating Costs
The operating costs are summarized in Table 10.
Chemicals and Wastes •
The solvent used in the vapor degreaser was Freon TF (CFC-113). In 1992 the company used 18,200
pounds of Freon at a cost of $2.67 per pound. The total cost of Freon was $48,594. The 1994 price for
Freon, including all taxes, is $11.2331 per pound. Parker would have to pay $204,386 to clean the parts
with Freon today.
Brulin Formula 815 GD, 3% by volume, is the detergent used in the ultrasonic tank. The detergent is
replaced every three months, and the annual cost for this cleaner is $49 (4 gallons * $12.12/gallon).,
Daraclean 282 GF at a 9% concentration is used in two of the spray washers that clean both aluminum and
steel parts. The detergent is replaced every month. The annual consumption of Daraclean is 76 gallons
per year, or $1,63632. Brulin 63 G at 9% concentration, is used in the third spray washer which cleans only
aluminum parts. The detergent is replaced monthly which results in a detergent cost of $498 per year33.
Li 1992,360,363 cubic feet of cooling water was used in the vapor degreaser. The sewer costs in the City
of Waltham for 1994 are $0.0283 per cubic foot. The total cost of wastewater is $10,198. As stated
previously, it was common practice for the machine operators to have containers of the chlorinated
solvents at their work stations for periodic cleaning needs. As a result, the waste oil from these machines
was contaminated with the solvent and required a higher price for disposal than if the oil had not tieen
contaminated. In 1992, the company had to dispose of thirty three drums of Freon-contaminated o:U, at a
cost of $230 per drum, or $7,590.34 The cost per drum of non-contaminated oil is $95. The difference in
disposal cost of the waste oil is $4,455. This cost can be attributed to the Freon vapor degreasing system.
There were two drums of spent Freon, 50% yield, sent to General Chemical Corporation. This resulted in
31 Van Waters and Rogers, Salem, MA, market price quote, August, 1994.
32 Service Chemical, North Andover, MA, market price quote, July 1994.
3:1 Brulin Corporation, Indianapolis, IN, market price quote, July 1994.
31 Laidlaw Environmental Corporation, North Andover, August, 1994. This price is an estimation; the exact price is determined
after a sample is analyzed.
38
-------
.i
-2.
no cost or gain for the company. Two filters on the vapor degreaser were replaced every week. The filters
were disposed of afong with other waste from the facility. It was impossible to estimate the cost of
disposal of the filters from this single process. Therefore these costs were not included in this analysis.
The total waste management cost for the vapor degreaser is $14,653 ($10,198 + 4,455).
Table lH Raker Hannifin Analysis Two - Operating Costs
Chemkai
Purchase*
sis
Freon
(first year only)
Brulin
Biulin & Daraclean
Waste •mgemait
Safety fcHMg/equip
Insurants
Fees
Filing EpeMui. time
AnmJiM-ai.
MaiHeoKe
Pnxtacfca
Utibta
Bg
labor
materials
elect
water
gas/steam
Tof li mm* pirating costs
.Ini IIMMlil nil flOTT
Vapor Degreaser
$204,386
NA
NA
$14,653
0
0
$5,172
$4,200
0
included in materials
$1,186
$54,570
$1,432
$5,802
0
$291,401
$286,184
Ultrasonic Tank
NA
$49
NA
$19
0
0
0
i o
0
$32
$24
0
$702
0
0
$826
Spray Washers
NA
NA
$2,134
$19
0
0
0
0
0
$64
$472
0
$1,697
$4
0
$4,390
There are no soarcgtefor the wastewater of the aqueous cleaning systems because these small quantities
of wastewater awreapoiated. The aqueous cleaning systems are equipped with oil skimmers that skim oil
from the cleaa*fc* water. Together the water-based cleaning systems produce 55 gallons per year of
oil which costs3MSfergallon to dispose. This figure is divided over the cleaning systems (ultrasonics,
spray washers arfAcinmersion tank addressed in Analysis One) by using the number of parts each
system cleans.
39
-------
-------
-------
I
I
As in the first analysis, it was impossible to account for the individual cost of filters and residuals from the
evaporator for this degreaser. The filters are disposed of along with other wastes from other processes at
the facility. The wastewater from the immersion process is a negligible amount of the waste that is
processed in the evaporator.
Regulatory Costs
The number of pounds of Freon used in the vapor degreaser required a fee under the Toxics Use Reduction
Act (TURA). The fee paid for 1992 was $5,172. The environmental manager estimated that 210 hours
were spent filling out TURA and SARA reports for the vapor degreaser in this analysis. At a wage rate of
$20/hour the cost for time spent on paperwork is $4,200. Once the company stopped using Freon, they no
longer were required to report under SARA or TURA.
As in the first analysis, due to the large quantity of water used in the vapor degreasing system, there would
be some cost associated with the permitting and sampling requirements. However, the company was
unable to provide any estimation of the time associated with these duties. For the purposes of this analysis,
then, it was assumed that there was no difference in costs between the two systems with regard to
permitting and sampling.
Production and Maintenance Costs
Operation of the vapor degreaser required an operator for 68 hours per week. The cost for labor was
$54,570 per year (68 hours/week * $16,05 * 50 weeks). Even though the parts have to be cleaned longer
in (he new cleaning systems, they do not require a full-time operator because the cleaning process is
integrated into the production process (i.e., the parts are cleaned in between other activities.) This worker
was reassigned within the facility.
Based on information supplied by the company, the maintenance costs for the vapor degreaser totaled
$1,186 per year. The maintenance of the ultrasonic system involves replacing the detergent and the filter,
The cost of labor associated with replacing the filter every three months is $24 per year. The cost of labor
for replacing the detergent four times per year is $32, two hours per year at a cost of $16.05 per hour.
The labor costs for maintenance of the three spray washers are $64 (4 hours per year). Each of the spray
washers has a cartridge filter, $129 each, and 2 micron filters, $43 each. The cartridge filter is replaced
once a year and the micron filter is replaced four times per year at a total cost of $473.
Utility Costs
The vapor degreaser used 360,363 cubic feet of cooling water at a cost of $0.0161/ft3 in the city of
Waltham, or $5,802. The water in both the ultrasonics system and the spray washers is recycled and
replaced only when the detergent is replaced. Because the water from the rinse tanks is used for make-up
water in the wash tank, the cost associated of water consumption for the ultrasonic system is negligible.
The detergent is replaced only 4 times per year for a total water consumption of 15 cubic feet The water
cost for the spray washers is $4 (3 spray washers * 73 cubic ft water * $0.0161/ft3).
Based on vendor estimates, the electricity cost for the vapor degreaser is $ 1,432. The ultrasonic system
consumes 18 KW and operates 6 hours per week for 50 weeks. The cost of electricity in the city of
Waltham is $0.13/KWH. The yearly electricity cost for the ultrasonic tank is $702. The spray washers
use 8.7 KW, and they operate 30 hours per week for 50 weeks costing $1,697 per year. Because the
waistewater from the immersion process is a negligible amount of the waste processed in the evaporator, the
40
-------
energy costs of the evaporator that could be attributed to this process were assumed negligible and were
not calculated.
Comparison to Company Financial Assessment
The Parker Capital Appropriations Request Original Submission for the one large immersion system to
satisfy all cleaning needs showed a pre-tax rate of return of 81.6%. The request considered capital costs
(including freight, installation and engineering support) and the cost of removal of the old degreasers.
Operating costs considered were the cleaning agent, water use, direct labor, gas and electric utilities and
maintenance. The following costs were not included in the company analysis: waste management costs,
filing paperwork time and fees associated with the use of a listed chemical. These costs were quantified in
the TCA analyses. These three categories of costs amount to $39,963 ($48 for the aqueous system), or
27% of the total capital cost of the proposed project. Without considering these costs, the company's
original analysis vastly underestimated the success of this project
Project Outcome
The net present value of the investment is $700,125. (See Table 11.) This means that the projects returns
$700,125 more than the company requires for their investments. The payback period for the investment is
2.4 months (i.e., the savings of the new equipment were higher than the initial investment of $66,475 in
less than three months). For each dollar invested Parker will receive ten dollars during the economic
lifetime of the equipment
Table 11. Parker Hannifin Analysis Two: Option Analysis Summary35
Financial Indicators
Incremental cash flow (first year only) ,
- Depreciation •
Taxable income*
- Income tax (40%)* ;
Net income*
+ Depreciation "'
After tax cash flow*
Present value
- Total capital cost
Net present value
Benefits / cost ratio (NPV/capital costs) i
Payback period*
Value
$286,184
$9,496
$276,688
$110,675
$166,013
$9,496
$175,509
$766,600
$66,475
$700,125
10.5
2.4 months
*These figures are for the first year of the investment Subsequent year figures
will increase (except payback) with the increase in the CFC excise tax.
Often times the operating period of equipment is longer than the depreciation period. This means that the
profitability of the investment would increase even more. For example, if the equipment operates for ten
35 Results obtained using P2/Finance Software, Tellus Institute, Boston MA, 1995.
41
-------
years, the after tax cash flow for the last three years would fe over $170,000 with no depreciation tax
shield. If this after tax cash flow is discounted over years 8,9 and 10 of the investment, the net present
value of the investment would be greater than $1,000,000.
Lessons Learned
The aggressive tax on Freon and the cost of disposing of wastes containing Freon made the
switch to aqueous cleaning very economical.
By assessing the cleaning needs at various stages in the production process, Parker was able
to greatly improve the profitability of the investment by purchasing remote cleaning stations.
As in Analysis One, aqueous degreasing used less water than vapor degreasing because of the
large cooling requirements of the vapor degreaser.
Market Forge Financial Analysis
Background
This analysis was performed on the metal cleaning processes at Market Forge. Three situations were
analyzed: the vapor degreasing process with 1,1,1-trichloroethane, the petroleum naphtha solvent agitated
immersion system ,and the pressure spray aqueous system. The company uses a discount rate of 16% and
a labor rate of $15.00 per hour. The project has an economic lifetime of seven years.
Cleaning Operations
Market Forge previously used a 1,1,1-trichloroethane vapor degreasing system. Because of the
requirements of the Labeling Act of 1993, Market Forge management decided to consider the elimination
of 1,1,1-trichloroethane. On the recommendation of their vendor, Market Forge changed the cleaning
process to use a naphtha solvent as a replacement to 1,1,1-trichloroethane. As stated in Chapter 2, the.
welders have never been satisfied with the cleaning abilities of the naphtha solvent system. Based on the
technical evaluation for this project, Market Forge purchased an aqueous pressure spray washer. Total
Cost Assessment methodology was used to compare both alternatives to the vapor degreasing system.
Capital Costs
The vapor degreaser was modified for the use of a naphtha solvent by removing the heating capabilities.
This involved 5 hours of an electrician's time at a cost of $75.
With the new aqueous system, the vapor degreaser will be disposed. Estimated disposal cost of the vapor
degreaser is $2,000. Purchase price of the American Metal Wash Pressure Spray Washer was $36,000.
Installation required a contractor for plumbing and ventilation system work. The total amount of the
contract was $6,000. Electrical supplies for installation totaled $2,400. All capital costs were obtained
from Market Forge documents or personnel and are summarized in Table 12.
42
-------
Table 12. Market Forge -Capital Costs ,
Capital Costs
Equipment purchase
Disposal of old process
Initial permits
Building/process changes
Total Capita] Costs
Vapor Degreaser
'. NA
$2,000*
NA
NA
. NA
Naphtha Solvent
0
NA
0
$500
$500
Pressure
Spray Wash
$36,000
NA
0
$8,400
$46,400
•The $2000 disposal of the vapor degreaser is only incurred for the pressure spray wash system and not for the
naphtha solvent system.
Operating Costs
The operating costs are summarized in Table 13.
Chemicals and Wastes
Based on Market Forge records, the 1993 consumption of 1,1,1-TCA was 4,397 pounds. The switch to the
naphtha solvent was made on August 15,1993. Using the factor of 32/52 weeks, the projected use of
1,1,1-trichloroethane for 1993 is 7,145 pounds. At the 1994 price of $1.53 per pound36, the cost for 1,1,1
trichloroethane was $10,932.
In 1994, the company used 1,485 gallons (specific gravity = 0.770) of the naphtha solvent (CAS 64742-
88-7) at a total cost of $4,32i:
Based on testing in TURTs Surface Cleaning Lab, the detergent used in the spray washer is W. R. Grace's
Daraclean 283. Each time the water is changed, 15 gallons of the cleaner will be used. It is expected that
this water will be changed four37 times a year at a total cost of $1,140.
The waste management cost associated with the vapor degreasing system was the waste solvent reclaimed
by the vendor. In 1993, their was no cost to the company to dispose of 5,899 pounds of low yielding waste
solvent
The waste management cost associated with the naphtha solvent is the disposal of spent solvent In 1994,
the company disposed of 1,050 gallons at a total cost of $390.
The waste management costs associated with the aqueous cleaning process, without ultrafiltration are the
four times a year disposal of the spent bath. This amounts to 1,200 gallons of high pH, oily wastewater at
34 Ashland Chemical Corporation, market price quote, July 1994. This price includes the excise tax on ozone depleting
chemicals which is $0.435/lb for 1,1,1-trichloroethane. The;tax will go up to $0.535/lb in 1995 and will increase by $0.045/lb
each year thereafter. This tax increase is considered in the financial analysis.
37 Estimation from American Metal Wash personnel based on similar applications.
43
-------
a cost of $764 ($35 per drum)38 In addition, the spray system produces oil wastes that are skimmed off the
bath and filters that need to be replaced. The total disposal cost of oil skimmed from the cleaning system
will be negligible compared to the amount of oil disposed of by the company for other processes.
Regulatory Costs
There are no regulatory impacts with the switch to either new system. However, if the company had
continued to use 1,1,1-trichloroethane, they would have had to comply with the requirements of the
Labeling Act of 1993. This law requires the labeling of all products made with ozone depleting
substances, including 1,1,1-trichloroethane. In addition, if the company had continued to use 1,1,1-
trichloroethane, they would have been affected by the Clean Air Act Amendments (CAAA). By
discontinuing use of this substance, the costs of compliance with these laws were avoided. Since this
finamcial analysis was performed when the process was not regulated by the CAAA, these costs were not
quantified.
Production and Maintenance Costs
The vapor degreaser required an operator for 15 hours per week at a rate of $ 15 per hour ($11,250 per
year). The solvent immersion system requires the same operator time. However, there is an added cost
associated with the current system, because the welders have become so frustrated with the inability of the
current system to clean the parts adequately that they have begun cleaning by hand. It is difficult to
estimate the time that is being spent on this additional cleaning as it depends greatly on the frustration level
of the welder. It is estimated that an additional 60 hours per week are spent on this cleaning, at an annual
cost of $45,000. Even with this additional cleaning, the welders are not satisfied with the cleanliness of
the part. It is estimated that the aqueous system will require an operator for 15 hours per week at a cost of
$11,250 per year.
Based on Market Forge maintenance logs, the maintenance requirements for the vapor degreaser were two
operators for one day every four months to clean out the tank. This costs $720 per year. The naphtha
system requires one operator for one day every six months to clean out the tank. This costs $240 per year.
The naphtha system filter requires changing every three months. The filters cost $10 each and the cost of
labor for changing the filters is $15. (Total cost of maintenance for the current system is $240 + $40 +
$15, or $295.)
Maintenance on the aqueous spray washing system requires the monthly changing of the cartridge filter
and changing the bath four times a year. Cost of the filters are $5.75 each at a total cost of $69. Labor to
perform filter and bath changes totals $4539. >
Utility Costs
There was no water used in the vapor degreasing process. There was no water associated with the naphtha
solvent system. The aqueous system will use an estimated 1,330 gallons (1,200 gallons for bath changes
and 130 gallons40 for water replacement) of water per year at a cost of $120.
38 Based on Market Forge records for similar waste stream.
39 Estimation of American Metal Wash personnel based on similar applications.
40 Estimation from American Metal Wash representative based on similar applications.
44
-------
Table 13. Market Forge - Operating Costs
Operating Costs
Chemical
Purchases
1,1,1-TCA*
Naphtha solvent
Daraclean 283
Waste management
Safety training/equip
Insurance
Fees
Filing paperwork time
Annual permittin
Maintenance
r
labor
materials
Production costs
Utilities
elect
water
gas/steam
Total annual operating costs*
Incremental cash flow*
Vapor
Degreaser
' $10,932
NA
NA
0
0
0
0
0
0
$720
0
$11450
$7,020
0
0
$29,922
Naphtha
Solvent
NA
$4321
NA
$390
0
0
0
0
0
$255
$40
$56,250
negligible
0
0
$61.256
($31334)
Pressure Spray
Wash
NA
NA
$1,140
$764
0
0
0
0
0
$45
$69
$11,250
$513
$120
negligible
$13,901
$16,021
*These figures are for the first year of operation.
tax on TCA increases by $0.045/lb/yr.
In the remaining years these figures will go up as the excise
The vapor degreaser vendor estimates that the 1955 model degreaser consumes 54 KW.41 Operating 1000
hours per year and using an electricity cost of $0.13/KWH, the total annual cost of electricity for the vapor
degreaser is $7,020. It is difficult to estimate the electricity consumption of the naphtha system. Some
small amount of electricity is being used to provide agitation; this was assumed negligible. The cost of
electricity for the aqueous spray washer amounts'to $513. (23 amps * 220 V = 5060 W operating 15
hours/week = 780 hours per year = 3946.8 KWH 4 $0.13/KWH = $513)
Project Outcome
Using the figures presented, the net present value of switching from vapor degreasiag with 1,1,1-TCA to
the naphtha solvent is negative $73,680. This is due mainly to the extra costs incurred as the welders are
cleaning by hand. However, the full cost of continuing to use the 1,1,1-TCA system in the future is not
adequately represented because of the missing cost of compliance with the Labeling Law and the Clean Air
Act Amendments.
41 Estimation from Detrex representative.
45
-------
Because estimating compliance with these two laws is so difficult, an alternate strategy was employed
Using an iterative process with the P2/Finance software, it was determined that in order to have a net
present value in year seven of $0, a cost of $30,400 must be incurred by the vapor degreasing system. This
means that the cost of compliance with the Labeling Law and the CAAA must be less than $30,400 in
order tolnake staying with the 1,1,1-TCA vapor degreasing system economical. This result was discussed
with Market Forge representatives. Though the actual cost of compliance was not calculated, the
representatives were certain that the strict requirements of the Labeling Law and the CAAA could not be
met with such a small investment amount. In addition, compliance costs alone do not account for any
negative customer image that could be incurred by the company for compliance with the Labeling Law.
Based on this information, this investment could be considered financially viable for Market Forge.
Even if the cost of compliance mentioned above is ignored in the switch from the 1,1,1-TCA vapor
degreasing system to the aqueous pressure spray wash system, a net present value of positive $5,761
results. The main reason for the positive outcome in this situation is the high cost of 1,1,1-TCA and of
electricity for the old vapor degreaser. (See table 14 for the option analysis summary.)
Table 14. Market Forge - Option Analysis Summary42
financial Indicator
Incremental cash flow*
- Depreciation (7-year straight-line)*
Taxable income*
- Income tax (40%)*
Net income*
+ Depreciation
After tax cash flow*
Present value
- Total capital cost
Net present value
Benefits / cost ratio
Payback period*
Switch from Naphtha
Solvent to Aqueous
$47,315
$6,629
$40,686
$16,275
$24,412
$6,629
$31,040
$125,359
$46,400
$78,959
3.77
1.0 months
Switch from 1,1,1-TCA
to Aqueous
$16,021
$6,629
$9392
$3,757
$5,635
$6,629
$12464
$52,161
$46,400
$5,761
0.27
2.9 months
*These values are for the first year of the investment Subsequent year's figures, except for payback, would
be higher because the excise tax on 1,1,1-TCA is increasing.
42 Results obtained using Pi/Finance Software, Tellus Institute, Boston MA, 1995.
46
-------
Analysis of the switch from the naphtha solvent to the aqueous pressure spray wash system results a net
present value of positive $78,959. The reason for the positive outcome in this situation is the additional
cost incurred as the welders perform cleaning duties to make up for the inability of the current system.
Lessons Learned
The excise tax on 1,1,1-TCA made the switch away from its use more economical.
Cost for electricity for the 1955 vapor degreaser was more than for the new aqueous pressure
spray washer.
Incomplete technical evaluation of the "drop in" replacement cost the company an additional
$45,000 per year.
P2/Finance software can be used in an iterative process to test various scenarios when
estimations are difficult to make.
Company A Financial Analysis
Background
This analysis was performed on the potentially feasible options identified for Company A. The company
uses only pay-back period as a financial indicator and a labor rate of $30 per hour. To calculate other
financial parameters a discount rate of 16% was used. The economic lifetime of the project was estimated
at seven years. •
Cleaning Operations
The company currently uses TCE in a vapor degreaser. Finding a suitable cleaning alternative for this
company is very challenging because of the high demands for cleanliness and the wide variety of substrates
and contaminants. The aqueous based cleaners in the first two analyses, for example, were required to
remove a relatively well-known group of contaminants from one or two substrates. An alternative cleaning
system for Company A must be able to remove a large number contaminants from a variety of substrates.
In addition, the sizes of parts cleaned by this company vary greatly and the new system must be large
enough to accommodate the largest parts.
In recent years Company A has experienced an increased demand for cleaning. Previously the company's
suppliers performed more of the initial cleaning themselves but since costs for chlorinated solvents have
increased and CFCs were phased out, many of their suppliers are simply not cleaning anymore.
Based on the technical evaluation (see Chapter 2) four alternatives will be analyzed financially. The first
alternative is using a plastic media blast technique for 25% of their current cleaning needs and retrofitting
their TCE vapor degreaser to satisfy the other 75%. The second alternative is using fragmented CO2
technology for 100% of their current cleaning needs. The third alternative is to use an ultrasonic aqueous
cleaning tank to satisfy 25% of their cleaning needs and retrofit the TCE vapor degineaser to satisfy the
other 75%. The fourth option is to purchase a new vapor degreaser, using TCE, for 100% of their cleaning
needs.
47
-------
Capital Costs
For the first three analyses, there will be no disposal costs for the vapor degreaser because it will be
retrofitted and used for the bulk of the cleaning needs. Retrofitting requires cleaning the degreaser. For
these analyses, it was assumed that one drum of TCE will be disposed of from the cleaning at a cost of
S2S043. Retrofitting the current vapor degreaser includes adding 8 inches of freeboard and a chiller at a
cost of S^OOO44. Retrofitting is necessary for the plastic blast and the ultrasonic wash alternatives. For
the fragmented CO2 and the new vapor degreaser alternatives, it is necessary to dispose of the old
degreaser at an estimated cost of $2,QQQ*5. (Disposal also requires the clean-out cost of $250.)
Capital costs for a 36" by 48" plastic blast cabinet are $8,775. Capital costs for the fragmented CO2 system
are estimated at $80,000 for a system that would be able to accommodate all of Company A's cleaning
needs. A 100 gallon ultrasonics tank with oil skimmer from Blue Wave Ultrasonics in Davenport, Iowa
costs $24,500. A new "closed" vapor degreaser would cost $60,000. The capital costs are summarized in
Table 15.
Table 15. Company A - Capital Costs
Capital Costs
Equipment purchase
Dispose of/clean old
process
Initial permits
Building/process
changes
Total Capital Costs
Vapor
Degreaser
NA
NA
NA
NA
0
Plastic
$27,775
$250
0
0
$28,025
CO,
$80,000
$2,250
0
0
$82,250
Sonics
$43,500
$250
0
0
$43,750
New Degreaser
$60,000
$2050
0
0
$62,250
Operating Costs
The operating costs are summarized in Table 16.
Chemicals and Wastes
Based on company records, the 1994 consumption of TCE was 11,152 pounds. At the current price of
$0.83 per pound, the annual cost is $9,256. Two drums of contaminated TCE were sent to a reclaimer at a
cost of $50046.
Retrofitting the old degreaser will decrease the use of TCE by 50% as estimated by a representative of
Degreasing Devices Company. In addition, use will be decreased by 25% by diverting this amount of the
cleaning load to an alternate system. This results in a projected use of 4,182 Ibs TCE at a cost of $3,471.
Waste costs for the retrofitted degreaser are assumed to remain the same for this analysis.
43 Estimation from company representative.
44 Estimation by representative of Degreasing Devices Company.
45 Estimation based on similar applications.
46 General Chemical Corporation, Framingham, MA, market price quote, August 1994.
48
-------
The plastic media blast option requires the purchase of an estimated 300 pounds of plastic media at a cost
of $510. Disposal of the dirty media as non-hazardoius waste will cost approximately $50.47
It is difficult to estimate the cost of CO2 for the fragmented system because no operating data are currently
available for similar systems and applications. A rough estimate of $3,000 per year was made.
Table 16. Company A - Operating Costs
Operating Costs
Chem.
Purch.
TCE
plastic
CO,
235
Waste management
Safety training/equip
Insurance
Fees
Filing paperwork time
Annual permitting
• Mainten
ance
labor
materials
Production
Utilities
electricity
water
gas/steam
Total annual operating costs
Vapor
Degreaser
$9,256
NA
NA
NA
$500
0
0
$1,100
$1,050
$300
$6X1
0
$30,000
$2,600
0
0
$44,866
Plastic
$3,471
;$sio
NA
NA
$550
0
0
0
0
0
i$420
0
$60,000
$1,950
0
0
$66,901
CO2
0
NA
$3,000
. NA
0
incl purchase
price
0
0
0
0
$360
unknown
' $60,000
$2,600
0
0
$65,960
Sorties
$3,471
NA
NA
$532
$519
0
0
0
0
0
$92
$24
$30,000
$2,400
$40
0
$37,078
New
Degreaser
$4,628
NA
NA
NA
$1500
0
0
0
0
0
$60
0
$30,000
$910
0
0
$37,098
Assuming the aqueous bath in the ultrasonics tank is changed four times a year,48 the 7% Daraclean 235
will cost $532. There are no wastewater costs associated with this option because Company A has a
wastewater treatment unit that treats all the wastewater used at the facility. Waste oil skimmed from the
system will be disposed of with other oily waste from the facility so it is assumed negligible.
Based on an estimation by a representative of Degreasing Devices Company, the new vapor degreaser will
use an estimated 50% of the total amount of TCE currently used. This would cost Company A $4, (528 at
the current demand. Based on their experience with a manually operated sand blasting process, Company
47 Estimation from a representative of Dawson-McDonald Company.
u Estimation based on similar applications.
49
-------
A representatives estimated that the production costs of the plastic media blast system and the fragmented
carbon dioxide system would be twice that of the vapor degreasing system.
Regulatory Costs
Because the use of TCE is above the 10,000 pound threshold set by the Massachusetts Toxics Use
Reduction Act, a fee of $1,100 must be paid. In addition, planning for the reduction in use or byprodnct
production must also be completed. TCE is not the only chemical for which Company A currently plans.
The company estimates that $750 can be attributed to each chemical for planning and continuing education
time and fees. Due to the use of TCE, Company A currently files an Air Source Registration Report with
the Massachusetts Department of Environmental Protection. The fee associated with this permit is $300
and the company estimates that 10 hours is necessary to complete paperwork for this permit at a cost of
$300. Filing of the Air Source Registration Report would not be required with the alternative cleaning
systems.
Production and Maintenance Costs
For the current system, an operator is required for 20 hours per week to operate the vapor degreaser. At an
hourly rate of $30 this cost is $30,000 per year (50 week year). The operator performs other functions
during the cleaning cycle. The ultrasonic system and the "closed" vapor degreaser would require the same
production costs as the current system. It is estimated that the production costs of the plastic media blast
system and the fragmented carbon dioxide system would double as both processes are more labor-intensive
that the vapor degreasing process.
Based on company maintenance records, maintenance on the vapor degreaser is performed once per year
for 2 hours at a cost of $60. This maintenance cost would be the same for the retrofitted degreaser and the
new degreaser.
Maintenance associated with the plastic media blast option involves cleaning the dust bag and maintaining
the gloves and glass. The vendor estimates that 12 hours per year will be required at a cost for labor of
$360. When maintained properly, the dust bags do not have to be replaced.
Maintenance associated with the fragmented carbon dioxide process is changing the HEPA filters. Tlte
vendor estimates that 12 hours per year will be required at a cost of labor of $360.
There is a small amount of maintenance associated with the ultrasonic system to change the filters; this
totals an estimated $32 in labor and $24 in materials49.
Utility Costs
Vendor estimates of electricity requirements for the current vapor degreasing process are $2600. (20KW *
20 lirs/wk * 50 wk/year @ $0.13/KWH). The retrofitted degreaser would be used for 750 hours per year at
a cost of $1950.
The utility costs of the plastic media blast process are negligible as 45 cfm air is all that is required
Operating costs are not currently available for the fragmented carbon dioxide system. For the purposes of
this analysis, it was assumed that the electricity cost for operation of the current vapor degreaser and
operation of the fragmented carbon dioxide system would be the same. The ultrasonic system will operate
'" Estimation based on similar applications.
50
-------
50 hours per year at 18 KW (from vendor product literature) for a total cost of $450. The vendor of the
new vapor degreaser estimates electricity costs for 1000 hours per year at $910.
A water cost of $40 is attributed to the ultrasonic system (400 gallons per year). This is the only
alternative that uses water.
Project Outcome
None of the options evaluated resulted in a positive net present value at year seven. The net present values
at year seven for the options are ($75,097) for the plastic blast and retrofitting, ($114,382) for the
fragmented carbon dioxide, ($14,685) for the ultrasonic system and retrofitting and ($29,061) for the new
vapor degreaser. This is due to the fact that TCE is hot currently subject to taxes as in the cases of 1,1,1-
TCA and CFC-113 in the previous examples. In addition, the extra cost of production for the blasting
techniques made those options much less financially favorable than the other options. The financial
analysis is only one part of the information necessary to make the decision to stop using TCE for vapor
degreasing. There was no attempt in this analysis to estimate the cost of compliance with the Clean Air
Act Amendments. Company A may decide to invest in the new technology in order to avoid future
compliance costs.
Lessons Learned
Using the TCA methodology with estimated values early in the decision making process cam
help narrow the choices of technically-feasible alternatives.
Manual blasting technologies require more labor, and associated cost, than vapor degreasimg.
At its current state of regulation, TCE is relatively inexpensive to use and dispose of in
quantities less than thresholds for additional regulation.
Conclusions
For Parker Hannifin Analysis One, the biggest difference between the two systems, as a percent of total
operating costs, is in the waste management category. Waste management costs for the vapor degreaser
have more than doubled in two years time. The majority of the cost for waste management in the vapor
degreasing system is from the additional cost of disposing of oil contaminated with 1,1,1-TCA or METH
and the disposal of a large volume of cooling water. In the new aqueous system, both of these costs are
avoided. Again as a percent of total operating costs, the cost of maintenance is greater for the aqueous
system even though the actual maintenance costs for the two systems are nearly equal (See Table 17).
Although chemical purchases do not represent a large percent of total operating costs for the vapor
degreasing system, prices for these chlorinated solvents have risen sharply in recent years. The costs of
1,1,1 TCA and methylene chloride have doubled in two years and five years respectively. It is known that
the cost of 1,1,1-TCA will continue to rise and it is a good assumption that methylene chloride prices will
rise also, Other savings result from the reduction in utilities consumption. In some situations, electricity
costs are higher for aqueous cleaning systems than for vapor degreasers. However, in this case the
immersion tank only operates for 20 hours per week and the vapor degreaser operated 68 hours per week.
51
-------
J
The vapor degreaser cleaned smaller loads iliore frequently arid the immersion tank cleans larger loads less ;
often. i
For Parker Hannifin Analysis Two, the largest differences between the two systems, as a percent of total ;
operating costs, are in the waste management and utilities categories. The price for a pound of Freon has ;
increased by more than 400% in the last two years. Although as a percent of total operating costs, the ;
utilities category is higher for the aqueous system (46.1%) than for the vapor degreasing system (2.5%), j
the actual costs for utilities for the aqueous system is much lower ($2,403) than for the vapor degreasing
system ($7,234). See Table 17. Furthermore, the waste disposal costs for wastes containing Freon have
increased by 50% percent. Large savings in operating costs are realized because the aqueous cleaning i
system does not require a full-time operator: A careful analysis of the cleaning needs allowed the company '
to save money on the investment by buying separate systems designed for specific cleaning needs. The j
alternative would have been to design the cleaning system to the highest need for cleaning and size the '•
ultrasonic system to that need which would have increased the investment costs dramatically. '
For the Market Forge analysis, as a percent of total operating costs, the vapor degreasing system is higher ,
than the aqueous system in the categories of chemical purchases and utilities, and lower in the category of '
production. (See Table 17). As stated previously, the cost of 1,1,1-TCA has doubled in two years and will
continue to rise due to the excise tax of $0.045/lb/yr. Therefore, chemical purchases as a percent of total
operating cost would be expected to increase beyond the 36.5% calculated for 1994. The cost of chemicals
for the aqueous system as a percent of total operating cost is only 8.2%. Due to the arrangement that \
Market Forge had with their 1,1,1 -TCA supplier, the cost of waste management, as a percent of totall I
operating cost, is slightly (though not significantly) higher than for the aqueous system. It is expected that
the cost for waste management of 1,1 1-TCA will increase as the phase-oat approaches. There is a large ;
difference in production costs, as a percent of operating cost, between the two systems. Production costs
for the vapor degreaser are 37.6% and for the aqueous system are 80.9% of total operating costs though the '
actual annual cost for both systems is the same ($11,250). As a percent of total operating costs, the utilities i
category is lower for the aqueous system (4.6%) than for the vapor degreaser (23.5%). [
The first two analyses in this report are clear examples of success stories of switching from chlorinated •
solvent cleaning to aqueous cleaning (net present values of $40,940 and $700,125 respectively). In the :
third analysis, the net present value is much less than in the first two analyses. However, the net present
value for this investment is still positive and the cost of compliance with the CAAA and the Labeling Law !
was not included. If this cost was included, the NPV of this value would dramatically increase.
There are two major differences between the first three analyses and the final analysis (Company A).. First, :
Company A has much more complex demands for the cleaning system because of multiple contaminants !
and substrates whereas the cleaning systems in the first three analyses remove a relatively known group of
contaminants. Second, the first three analyses involved solvents that were strictly regulated whereas, TCE
is not as strictly regulated because it is not an ozone depletor.
It should be noted that costs for safety equipment, training and insurance did not influence the outcome of
the projects. There were no training programs that focused solely on the chlorinated solvents. Training
specific to the chlorinated solvents was included with other operator training. There were no reductions in ,
insurance cost at either company. One company was self insured and did not adjust the insurance costs i
because of the new cleaning system, and insurance premiums for the other companies would not be
affected by the alternative cleaning system.
52
-------
Additional benefits of environmentally-sound investments decisions not quantified include:
»• customer satisfaction; customers increasingly demand environmentally sound products and
production processes,
'»• public image,
»• reduction in exposure to communities and workers,
>• avoided future liability.50
These benefits were not included because they are difficult to quantify and because none of the companies
in this project had attempted to quantify them.
Category
Chemical purchases
Waste management
Regulatory compliance
Maintenance
Production
Utilities
Parker HanniGn -1
Vapor
deg.
6.2
60.9
0.0
3.9
0.0
29.0
Aqueous
system
25.9
0.4
0.0
44.6
0.0
29.2
Parker Hannifin - 2
Vapor
deg.
70.2
5.0
3.2
0.4
18.7
2.5
Aqueous
system
42.0
0.7
0.0
11.3
0.0
46.1
Market Forge
Vapor
deg.
36.5
0.0
0.0
2.4
37.6
23.5
Aqueous
system
8.2
55
0.0
0.8
80.9
4.6
Environmental costs have become significant factors in investment decisions. Prices for chemicals have
increased and will continue to increase because of taxes and fees on use. Waste management costs 'will
continue to increase as regulations become more strict. Insurance companies often increase their premiums
for companies with an environmental record.
All of these factors point to the need for a different perspective on investments in environmentally sound
products and production processes. The goal of this report was to recognize all benefits and costs of both
old and new systems. This was done by expanding the cost inventory and directing costs and benefits
directly to processes and products. Often times these costs were hard to quantify because information was
not easy to obtain and indirect costs had to be divided over multiple cleaning systems.
The question is whether expanding cost inventory and direct allocation of costs is enough to recognize all
aspects of investments in the environment Where relevant the time horizon of the project was increased to
show long term benefits. This was feasible because the economic lifetime of investments is, for the most
part, longer than its depreciation period. Net present value analysis was used because it allows for
expansion of the time horizon of an investment, and it is more complete because it accounts for the time
value of money.
30 Northeast Waste Management Officials' Organization, Massachusetts Office of Technical Assistance, "Improving Your
Competitive Position: Strategic and Financial Assessment of Pollution Prevention Projects", 1994.
;53
-------
One disadvantage of the net present value method is that any new investment is evaluated against an
alternative of not undertaking the new investment. ThisJstatus quo alternative often has a significant
influence on the project outcome even if it is not realistic.
The Total Cost Assessment methodology was used in three different ways in this section. It was used to
prove the economic viability of projects that had already been implemented as in the two Parker Hannifin
examples. It was used to estimate compliance costs in order to obtain a net present value of zero in the
seventh year of the investment. This compliance cost could then be compared to company estimates; of the
actual cost so that a decision could be made whether to implement the alternative. And finally, the TCA
methodology was used early in the decision-making process to narrow the choices of alternatives.
54
-------
Chapter 5
Substitution Analysis
Introduction
Every day people in manufacturing facilities make decisions concerning their use of chemicals. These
decisions are driven by many factors including the desire to develop new products, regulatory
requirements, the need for improved technical and cost performance of current processes, and higher level
management decisions that force changes at the production level. The ability to make informed decisions
about these alternatives is important for the health and safety of the workers and the public and for the
protection of the environment. While many decision making methodologies have been developed to help
people make informed decisions, it is recognized that there is no generally agreed on and reliable method
for evaluating the risk of alternative chemicals as a consideration in substitution decisions. As a result, the
effect of these decisions on worker or public health or on the environment is rarely considered, especially
by small and medium sized firms.51
The idea of addressing all environmental aspects of processes and products, the so-called "cradle to' grave"
approach, into the decision making process is over twenty five years old. Originally, these efforts were
termed life cycle analysis (LCA). In 1969, Coca-Cola sponsored a study that analyzed packaging for its
environmental, energy and financial impacts from cradle to grave. Since then, LCA has developed into an
important decision-making tool. Much work continues to improve the effectiveness of LCA, but its use
requires large investments of time and money and is, therefore, used mainly by large companies and
government agencies making significant decisions.
Appendix J at the end of this report contains an annotated bibliography of many of die methodologies that
have been developed for the purpose of making informed decisions concerning substitutes. Most of these
methodologies, including LCA, still require an extensive amount of data and some contain elaborate
ranking systems. This requires a large investment of time and money for the person laced with making a
decision. For the small and medium sized business person, the luxury of time and money is not practical.
In addition, many of these methodologies do not incorporate information about worker health and safety
and thus have the potential to result in the shifting of risks. The goals of the substitution analysis, as
described here, are 1) that it be practical for use by people in small and medium sized businesses arid 2)
that it include worker health and safety concerns along with the environmental and public health
considerations.
In order to satisfy the goal of practicality, the substitution analysis approach must relax some standards for
detail and scoring that are found in other methodologies. The thinking behind substitution analysis is that
each company faced with a decision must make that decision based on their own set of circumstances and
their own driving forces. This means that most of the work will have to be done by me person making the
decision. Substitution analysis will provide the framework, but it will not do the work. Unfortunately, this
31 Gray, George M. and Jennifer Kassalow Hartwell, The Chemical Substitution Tree", Pollution Prevention Review, Spring
1995, pp 7-17. . :
55
-------
approach does not result in the ideal of a quick and easy software package for decision making. However,
it does result in a framework that can be usecl to help individuals make the important decisions. One
source of information for this framework comes from many hours of experience with Massachusetts Toxics
Use Reduction Planners52. The individuals making toxics use reduction decisions, especially those in small
and medjum sized businesses, come from a wide variety of educational backgrounds and may not always
possess adequate knowledge concerning potential hazards of alternative technologies. This framework is
mesint to fill in the potential gaps in the education of these individuals. The transferability to similar
situations is obvious.
Substitution Analysis and the Decision Making Process
In evaluating potential substitutes, the overall decision making process has at least three components:
technical evaluation, cost assessment, and environmental, health and safety and regulatory considerations.
While the technical and cost assessments, addressed earlier in this report, are not simple, the third step,
here termed substitution analysis, is perhaps the most difficult First .a chemical inventory must be taken
(e.g., number of pounds of TCE released to the air), then potential hazards must be assessed, and finally a
judgement must be made concerning the impact When performing a substitution analysis, a statement
from work on life cycle assessment must be remembered, "any interpretation beyond the less is best'
approach is subjective".53
Each facility and each project may have different priorities for making decisions about whether or not to
implement a particular chemical or process change. Faced with the phase-out of CFC's and 1,1,1-TCA, the
technically proven excellent degreasers, companies are faced with a wide variety of options. It is possible
that there are many technically feasible alternatives and it is possible that many options are also desirable
economically. In this case, a substitution analysis could provide crucial information on which to base a
decision. However, there may not always be so many good options. Some decisions may be driven solely
by interest in improving environmental or safety performance. In this case, the substitution analysis could
be performed on likely candidates even before the technical and economic feasibility studies. For the
applications considered her, for example, supercritical carbon dioxide would have failed based on
economic feasibility alone and perfluorocarbons would have failed based solely on their regulatory
uncertainty. Other options are not so clear cut
Parker Hannifin chose to evaluate only aqueous cleaning processes. Inspired by a management mandate,
they performed a very non-systematic substitution analysis and decided to purchase the least controversial
system possible. The technical feasibility and economics were important but the cost of the system was not
the main driving force for change.
Market Forge, also inspired to changed by a management mandate, chose to rely on supplier information
which resulted in a different potential worker health problem (i.e., the exposure of the welders to fumes)
than was present with the chlorinated solvent This experience resulted in a general distrust of all die
available solvents that were potential replacements for the 1,1,1-TCA process. Had a technical assessment
been conducted on the naphtha solvent, it would have failed without need for information about its
economic, environmental or safety performances.
52 As mandated by the Massachusetts Toxics Use Reduction Act, the Toxics Use Reduction Institute trains individuals prior to
certification as Toxics Use Reduction Planners.
a "Life Cycle Assessment: Inventory Guidelines and Principles" EPA Office of Research and Development, February 1993.
56
-------
i-
In the cleaning situation at Company A, many options appear technically feasible: plastic media blast,
fragmented carbon dioxide blast and aqueous cleaning with ultrasonics. In this case, a substitution .analysis
of the alternatives will provide additional crucial information to the decision making process.
Performing a Substitution Analysis
In order to perform a substitution analysis, a worksheet was developed listing all of the various data, that
should be considered when making an informed decision about the environmental, health and safety
aspects of a new process. The worksheet is included as Appendix E. The worksheet includes all of the
criteria (defined in Appendix F) that the methodologies reviewed for this project suggested be taken into
consideration. It was developed with the specific application of solvent substitution in mind. It is more
broadly applicable, but may require some modifications for other purposes. For simplicity, the worksheet,
as presented here, allows tire comparison of only two alternatives. It can be expanded to allow multiple
comparisons, if desired. It is the intent of this exercise to identify areas of potential concern so that
companies can make informed decisions. To make this analysis more practical, raw material production,
recycling and fate after disposal were not considered.
The various categories on the worksheet allow either specific numerical values to be entered (e.g.,
permissible exposure limit in ppm), or a choice of alternatives (e.g., yes, no, suspect). In either case, the
values entered for each alternative can be compared to determine whether, for this factor, the change to the
alternate system is a positive or a negative. A column is also included to indicate whether the factor under
consideration is judged to be important for this particular analysis (relative hazard Mgh/medium/low).
Using the Worksheet
There are five steps involved in using the worksheet to assess the environmental, health and safety issues
for alternative processes.
1. Inventory the chemical use and discharges for processes.
2. Decide which areas of concern these inventory results suggest
3. Within each area of concern, find values for the criteria for both systems.
4. Decide whether a change to the new system would result in a positive or negative impact
5. Make judgements about the relative hazard for each criteria for which values were found.
The positive and negative impacts can then be assessed for the alternate process examined. Many
processes can be compared in the same manner. Each step will now be described in more detail using
Market Forge's original decision between 1,1,1-trichloroethane and the naphtha petroleum distillate: as an
illustration. See the worksheet in Appendix G for actual values.
First, the chemical inventory must be taken. The inventory requires information about chemical use,
releases and transfers. Much can be learned from this information. In this case, it is readily apparent that
the discharge to air of both of these substances is the largest area of concern.
The decision maker must then evaluate the chemical use pattern in the production process to determine hi
which of the following areas these inventory results will most likely have significant effect (for the current
process and the alternative).
>• potential for inhalation
> potential for ingestion
>• potential for skin contact
is?
-------
-- -
»• potential for eye contact *"' .^ *
> potential as a carcinogen, teratogen, mutagen, or other specific effect
>• potential for exposure to physical hazards
»• potential for release to air
'»• potential for release to water
*• potential for release to land
> important physical and chemical characteristics of the material
+ regulatory issues
*• energy and resource information
In this case, some of the 1,1,1-TCA is captured in an exhaust system and vented to the outside, but worker
exposure is still likely because it is an open system so the potential for inhalation is high. Ingestion is not
likely to occur so this category can be ignored. Skin contact and eye contact are not likely, but there is
potential for some exposure so this category was explored further. Physical hazards are of particular
interest to the decision maker in this example. As stated earlier, the results of the inventory showed a great
potential for release to air.
The potential for release to water was not included due to the very low probability of occurrence. Based
on the inventory information alone, there was a potential for release to land. However, the decision maker
knows that the material is being reclaimed, so this category was not explored further. It was assumed for
this example that the decision maker had particular interest in other important characteristics, regulatory
issues and energy and resource information. Equipped with mis information, the decision maker can save
time by assessing the criteria only for the issues of concern.
Under the category of potential for inhalation, there are five criteria. (The criteria are defined in Appendix
F.) The only criterion for which data are available for both chemicals is the permissible exposure level or
PEL. For 1,1,1-trichloroethane, the PEL is 350 ppm and for the naphtha solvent, the PEL is 100 ppm.
From the definitions, a lower PEL is less desirable, so the naphtha solvent is less desirable using this
criterion. Under the potential for skin contact category, it is reported that 1,1,1-trichloroethane causes
dermal irritation, and naphtha solvent does not Under the category of potential for eye contact, likewise, it
is reported that 1,1,1-trichloroethane causes eye irritation and naphtha solvent does not Under the specific
effects category, 1,1,1-trichloroethane is a suspected teratogen, carcinogen and mutagen while naphtha
solvent has none of these characteristics. For the physical hazards category, we are able to compare values
for the LFL/UFL, values for 1,1,1-trichloroethane are 7.5/12.5% and for the naphtha solvent, 1/6%. From
the definitions, the low value of 1% for the LFL of the naphtha solvent presents a greater potential hazard.
From the release to air category, we see that 1,1,1-trichloroethane is a global wanning material and an
ozone depletor whereas the naphtha solvent has neither of these characteristics. When comparing
evaporation rate in the "other important characteristics" category, it is found mat naphtha solvent has a
value of 6 and 1,1,1-TCA has a value of 151 (ether=l). From the definitions, higher is less desirable.
Comparison of vapor pressures results in the following, 1,1,1-trichloroethane is 100 mm Hg @ 20C and
the naphtha solvent is 0.5 mm Hg @ 20C. From the definitions, higher is less desirable, (i.e., 1,1,1-TCA
is more volatile resulting in higher airborne concentrations.) On the issue of regulatory outlook, 1,1,1-
trichloroethane is a HAP and a VOC and the naphtha solvent is neither.
The important findings from the comparative analysis are summarized in Table 18. For illustrative
purposes, assume that the most significant criteria are carcinogen, teratogen, mutagen, HAP, VOC,
NESHAP. The new system had positive values for each of these so that, in this case, the tradeoffs of the
substitution are clear. In an actual case, the company would have to look at all of the relevant factors and
58
-------
decide whether the tradeoffs were worth the benefits. In this example, the positives are definitely the fact
that the naphtha solvent is not a suspected teratogen, imutagen or carcinogen, has a low evaporation rate
and is not currently included on any regulatory lists. However, the naphtha solvent is flammable and has a
lower PEL than 1,1,1-TCA. This analysis highlights areas of concern and allows planning for minimizing
the potential for problems. ;
A similar analysis was performed for Company A. The worksheets used for the analysis can be found in
Appendix H. Because this situation is not the simple comparison of two different solvents, the worksheet
was used more to highlight potential problems of each option rather than to obtain a side by side
comparison. Table 19 shows the results of this comparison.
Criteria
PEL (ppm)
dermal irritation
eye irritation
teratogen
carcinogen
mutagen
LFL/UFL(%)
global wanning
ozone depleting
evaporation rate (ether = 1)
vapor pressure (mm Hg)
HAP
VOC
1,1,1-trichloroethane
350
yes
yes
suspect
suspect
suspect
7.5/12
yes
yes
151
100
yes
yes
naphtha solvent
100
no
no
no
no
no
1/6
no
no
6
0.5
no
no
positive or negative effect
of substitution
negative
positive
positive
positive
positive
positive
negative
positive
positive
positive
positive
positive
positive
59
-------
Table 19. Summary of Substitution Comparison of the Options to Replace TCE
Criteria
PEL (ppm)
TLV (ppm)
respiratory irritant
dermal irritation
ocular irritation
carcinogen
teratogen
mutagen
noise generation
high pressure
high temperature
global wanning
ozone depleting
photochemical smog
ecological effects in
water
HAP
vex;
TCE
50
50
yes
yes
yes
suspected
suspected
suspected
minimal
no
yes
no
no
yes
no
yes
yes
••. Plastic,,/;
none
none
no
no
no
no
no
no
yes
yes
no
no
no
no
no
no
no
CO,
5000
5000
asphyxiant
yes
no
no
experimental
no
yes
yes
no
yes
no
no
no
no
no
Daradean 235
(triethanolamine, 2%)
none
5 mg/m3 M
yes
yes
no
no
no
no
yes
no
ye*
no
no
no
possibility
no
no
The concerns that are highlighted by the substitution analysis for the use of TCE are that it has suspected
chronic effects of carcinogenicity, teratogenicity and mutagenicity. It is an irritant to the respiratory tract,
the skin and the eyes. It contributes to photochemical smog and is therefore regulated as a HAP under the
CAAA.
The option of plastic media blast introduces the potential worker safety issue of a pressurized system; the
current system also is pressurized. If this option was chosen, the workers would need to be trained in its
use and warned of the possible dangers. This process also introduces additional noise into the workplace
that must be taken into account
When assessed as a substitute for TCE, the option of fragmented CO2 technology also introduces the issue
of a pressurized system and the potential for noise beyond the OSHA allowable level. In addition, CO2 is
an asphyxiant but with a high TLV so that the potential for over-exposure is low. CO2 is an experimental
M Note that the units for the TLV for triethanolamine are mg/m3. This represents exposure in the liquid (droplet) form and
cannot be compared to values for vapor exposure measured in ppm.
60
-------
teratogen and contributes to global wanning. When assessing the data gathered, the decision maker must
keep the information in context In the case of the fragmented CO2 system, it is a closed system for the
worker and the potential for worker exposure is much less than for the open vapor degreaser for instance.
The CO2 will exhaust to the atmosphere, where its concentration will be quickly diluted.
From the analysis of the aqueous system, it is learned that one of the components of the detergent is a
respiratory and dermal irritant. However, this component is only 2% of the formulation. The aqueous
process operates at high temperature and creates an aqueous waste where the other options do not The
detergent product literature claims biodegradability. •
Limitations
A substitution analysis performed using the procedure outlines here is qualitative in nature. Two
alternatives are compared using a variety of criteria, but no final "score" is calculated. In order to quantify
the analysis, numerical scores would first have to be assigned to each of the criteria. For example, the
PEL could be given a score of 1 if it was greater than 200 ppm, 2 if it ranged from 100-200 ppm, 3 if it
ranged from 25-100 ppm, 4 if it ranged from 5-25 ppm, and a score of 5 if it was less than 5 ppm. Once
each category was scored, the relative importance of i each category would have to be determined. For
example, it might be decided that the PEL was twice as important as the IDLH; in this case, the PEL score
would be multiplied by two.
Once such a scoring scheme was developed, each alternative could be given a numerical value, and the
"best" alternative could be identified. Although this quantitative approach would appear to have value,
one problem is the allocation of scores and weights in a scientifically valid manner. TURI is currently
pursuing research hi quantitative substitution analysis.55
Conclusions
The substitution analysis described here is thus qualitative in nature. It allows the comparison of
alternatives using many criteria, but a final decision as to the best alternative, must be made by the
investigator. This approach is meant to highlight both the areas of concern for alternative substitute
processes and areas where those substitutes are clearly superior to the current process. This worksheet will
aid the decision maker to make informed decisions without overlooking important issues. Unfortunately
the worksheet will not make the decisions and it does require work to obtain the information, but only in a
perfect world could there be decisions without tradeoffs and software to make the decisions. Appendix I
contains a list of useful references for obtaining the information for the substitution analysis. Appendix J
contains an annotated list of relevant work on substitution analysis.
45 Tickner, Joel, "Development of a TUR Options Assessment Tool", TURI Research Fellow Project, 1995-96.
61
-------
Chapter 6
Overall Conclusions
This project studied three principle 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 other competing substitute technologies. The steps can be
performed in any order and their relative importance can vary from project to project The technical
evaluation of a potential replacement process for an existing technically successful process is often the
most important evaluative step. The success or failure of the technical evaluation determines whether the
alternative process will be evaluated further. Complete technical evaluation at the lab and pilot scale levels
can lead to a smooth transition into the new process. An incomplete technical evaluation can lead to
unforeseen problems with the incorporation of the new process and necessitate further evaluation following
installation. An economic evaluation of a technically-proven chemical or process provides valuable
information affecting the decision to implement or not Traditional financial analysis, however, often
includes only the costs directly 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 such elements as staff time for environmental reporting, waste
management costs, and permitting fees. The results of the financial assessment further inform the decision
whether to adopt the alternative. However, technical and financial information together are not sufficient
for decision making. Further evaluation is required to assess the environmental, health and safety issues
involved with the chemicals and processes. While the technical and cost assessments are not simple, the
environmental, health and safety assessment here called substitution analysis, is perhaps the most difficult
because there is no generally agreed-on and reliable method for evaluating the environmental and worker
health and safety risk of alternatives.
In using the three evaluative steps described above, it is important to remember 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 companies had different
motives for seeking substitute 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 being placed on one evaluative step on a given project, all three aspects
must be evaluated so that valuable pieces of information are not ignored.
Parker Hannifin, for example, chose to evaluate only aqueous cleaning processes based primarily on
environmental, health and safety, and regulatory reasons. Inspired by a management mandate to eliminate
all chlorinated solvents for fear that like CFC's, they might also be banned or heavily regulated, they
performed a non-systematic "substitution analysis" and decided to purchase the least controversial system
possible. The technical feasibility of aqueous cleaning seemed good and economics were not as much of
an issue as it was a management mandate. They, of course, wanted effective cleaning for the lowest cost
possible, but the cost of the system was not the main driving force for change. For mis reason, the
62
-------
environmental, health and safety, and regulatory evaluation step was the most important for Parker
Hannifin.
Market Forge, originally inspired by the Labeling Law to eliminate the use of 1,1,1-TCA, chose to rely on
supplier information which resulted in a technically inadequate system with potential worker health
problems. Had a technical assessment been conducted on the naphtha solvent prior to its use, it would
have failed without need for information about its economic, environmental or safety performances. This
experience resulted in a general distrust of all solvents that were potential replacements for the 1,1,1-TCA
process; because of this, the technical assessment of aqueous cleaning was the most important piece in the
decision-making process.
At Company A, many cleaning options appeared technically feasible; including plastic media blast,
fragmented carbon dioxide blast and aqueous cleaning with ultrasonics. The substitution analysis of the
alternatives provided additional crucial information to the decision making process. However, at the
current state of regulation of TCE, the economic evaluation would perhaps most influence a decision to
eliminate or decrease the use of TCE.
Many other conclusions regarding the cost of new systems, situation-specific chemicals and processes, and
"drop-in" replacements can be drawn from this study. Considering the cost of new systems, the foEowing
conclusions were drawn: 1) if the aqueous systems are replacing older equipment, a savings in electricity
costs may be realized, especially if hot air drying is not required; 2) depending on the cooling capacity of
the vapor degreaser, the aqueous systems may actually use less water; 3) the profitability of an investment
in aqueous cleaning equipment can be improved by purchasing based on cleaning needs at different stages
in the production process; 4) the aggressive taxes on CFC's and TCA have made the aqueous alternatives
economically feasible; and 5) the Total Cost Assessment methodology (P2/Finance Software) can be used
in an iterative process 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 requirement could be met for a
certain "cost" rather than actually attempting to place a value on meeting the regulatory requirement
Under the category of situation-specific chemicals and processes it was concluded that rinsing of a non-
silicated cleaner is not always necessary even when a painting operation follows and aqueous immersion
cleaning can be a viable option for steel and aluminum substrates either prior to nitriding or following heat
treat operations. For "drop-in" replacements, it was concluded that a thorough technical evaluation of so-
called "drop-in" replacements is necessary to avoid unforeseen costs and that job shops present an (as yet)
unmet challenge to the vendors of "drop-in" replacements making the gradual phase-out of chlorinated
solvents a possible option.
This project provided many conclusions regarding the decision making process used to evaluate alternative
technologies, as well as general conclusions from the evaluations of the cleaning situations at the three
participating companies. This work is part of a larger program at the Toxics Use Reduction Institute that
includes laboratory assistance to companies through TURTs Surface Cleaning Laboratory, Research
Fellows projects on "closed-loop" aqueous cleaning systems and further development of the substitution
analysis, and the preparation of a manual "Cleaning is Greener in Massachusetts" in conjunction with the
Office of Technical Assistance for Toxics Use Reduction. Through these ongoing activities the concepts
and techniques developed will be further developed and disseminated.
63
-------
•SS:
References
Adickes, Martin, Kenneth Humphreys and R. Butner."Computer Methods to Support Life-Cycle
Assessment". Battelle Pacific Northwest Laboratories, American Institute of Chemical Engineers 1993 '
Summer National Meeting, August 15-18,1993. : ' ;
Amey, Earle, "Product Life Cycle - The Broad View Perspectives on Material Usage". U.S. Bureau of I
Mines, WasteTech '91 Canadian Waste Management Conference, October 29-November 1,1991. |
Baumann, Henrikke and Tomas Rydberg, "Life Cycle Assessment: A Comparison of Three Methods for i
Impact Analysis and Evaluations" Journal of Cleaner Products, Volume 2, Number 1,1994, pp. 15-20. ;
Bird, Robert Wolfgang and Bernard A. Donahue. "Aqueous Alkaline Cleaners: An Alternative to Organic ;
Solvents". US Army Corps of Engineers Construction Engineering Research Laboratories, September
1993. . . ;
Booth, Steven, Linda Trocki and Laura Bowling, "A Standard Methodology for Cost-Effectiveness i
Analysis of New Environmental Technologies". Los Alamos National Laboratory, June 22,1993. j
i
Center for Clean Products and Clean Technologies, University of Tennessee. "Chemical Hazard Evaluation !
for Management Strategies: A Method for Ranking and Scoring Chemicals by Potential Human Health and '
Environmental Impacts" EPA Document EPA/600/R-94/177, June 1994. j
i
Center for Clean Products and Clean Technologies, University of Tennessee, "Comparative Evaluation of
Chemical Ranking and Scoring Methodologies" April 7,1994. i
Chemical Economics Handbook. C; Chlorinated Solvents. SRI-International, 1992. j
Chemical Marketing Reporter, "Detergents '93" January 25,1993. !
Cushnie, George Jr., "Pollution Prevention and Control Technology for Plating Operations". National i
Center for Manufacturing Sciences & National Assocaition of Metal Finishers, First Edition, 1994, pp.
228-233. i
Davis, Gary et al., "Chemical Hazard Evaluation for Management Strategies: A Method for Ranking: and '
Scoring Chemicals by Potential Human Health and Environmental Impacts". EPA ORD, September 1994, .
EPA/600/R-94/177. i
i
Dyer, J.A. & Mulholland, K., Toxic Air Emission: What is the Full Cost to Your Business?. Chemical
Engineering, February 1994. i
Fuchs, John F., "Ultrasonic Cleaning Fundamental Theory and Application" Blaskstone Ultrasonics, '
Jamestown, NY. •
64 i
-------
Golden, J.L., Vapor Degreasing Alternatives In Metal Cleaning Applications: Evaluation of Aqueous
Degreasers. Session V, SUR/FIN '92-Atlanta, June 1992.
Gray, George and.Jennifer Hartwell."The Role of Risk in Chemical Substitution Decisions". Harvard
Center for Risk Analysis, Harvard School of Public Health, prepared for TORI, July 1994.
Grimsted, Bradley, et al., "A Multimedia Assessment Scheme to Evaluate Chemical Effects on the
Environment and Human Health" Pollution Prevention Review, Summer 1994, pp. 259-268.
Hayes, R. H. & Garvin, D., Justifying Investment in New Technology, published in the reader for cost
analysis, Erasmus University, Rotterdam, The Netherlands, 1991.
Hermansen, LA, et al., "Hazardous Material Life-Cycle Cost Model" Naval Health Research Center,
Technical Document 93-4D.
Hill, Elizabeth, "Carbon Dioxide Snow Examination and Experimentation". Precision Cleaning, February
1994, pp 36-39.
Jacobs Engineering Group. "Source Reduction and Recycling of Halogenated Solvents: Life-Cycle
Inventory and Tradeoff Analysis". 1992. 1
Keoleian, Gregory A. "Pollution Prevention Through Life-Cycle Design" Industrial Pollution Prevention
Handbook by Harry Freeman McGraw-Hill, Inc. 1995.
Kranz, P.B., Erie Country of Environment and Planning, Division of Environmental Compliance, Buffalo,
New York, Ultrasonic Cleaning as a Replacement for a Chlorofluorocarbon-based System. November
1993. i
Massachusetts Toxics Use Reduction Institute, The Cost of Changing: Total Cost Assessment of Solvent
Alternatives. University of Massachusetts Lowell. 1994.
Marino, F. A., The Environmental Impacts of Alternatives to Ozone Depleting Solvents. Raytheon
Company, Lexington, Massachusetts, 1991.
Moore, Stephen and Sam Samdani, "New Roles for Supercritical". Chemical Engineering, March 1994, pp
32-35.
National Pollution Prevention Center for Higher Education, Accounting Module Summary. University of
Michigan, School of Natural Resources and Environment, August 1993.
Northeast Waste Management Officials' Association, Massachusetts office of Technical Assistance,
Improving Your Competitive Position: Strategic and Financial Assessment of Pollution Prevention
Projects. Training Manual, 1994.
Pacific Northwest Pollution Prevention Research Center, Environmental Economics: What's the Bottom
Line?. Summer 1993.
65
-------
Pekelney, David, "Analyzing Environmental Policies for Chlorinated Solvents with a Model of Markets |
and Regulations". A RAND Graduate School Dissertation; November 1990.
Pollution Prevention Advisor, "CO-, Does Snow Job on Contaminated Surfaces". Volume 5, Number 5, !
May 1995. \
Science and Technology Center, Tufts University, Financial Analysis of Pollution Prevention Projects. j
October 1991. !
SETAC, "A Technical Framework for Life-Cycle Assessment". SETAC, January 1991, j
{
SETAC, "A Conceptual Framework for Life-Cycle Assessment". SETAC, March 1993. <
Shapiro, Karen, "To Switch or not To Switch: A Decision Framework for Chemical Substitution" Pollution '
Prevention Review, Winter 1993-94.
Staliel, W.R., "Life-Cycle Assessment: A European View" Product-Life Institute, American Institute: of
Chemical Engineers 1993 Summer National Meeting, August 15-18,1993.
Stephen, David, Robert Knodel and James Bridges, "A "Mark I" Measurement Methodology for Pollution
Prevention Progress Occurring as a Result of Product Design Decisions". USEPA RREL, November 1994.
Tellus Institute, Boston MA, P2/Finance User's Manual. Pollution Prevention Financial Analysis and Cost
Evaluation System. 1993.
Technology Review, "The Haze Around Environmental Audits" Technology Review, April 20,1992.
Tiley, Jaimie, "Solvent Substitution Methodology using Multiattribute Utility Theory and the Analytical
Hierarchical Process". Department of the Air Force, Air Force Institute of Technology, Wright-Patterson
Air Force Base, OH.
TURI. "Blanket Wash Technology Study: An Evaluation of Commercially Available Blanket Washes"
TURI Technical Report No. 16,1994.
Underwood, J.D., Going Green for Profit- Industry has Barely Tapped its Potential. EPA Journal, July-
September 1993.
US Army Corps of Engineers, Construction Engineering Research Laboratories, Technology for Waste
Solvent/Oil Recycling. Aqueous Alkaline Cleaners: An Alternative to Organic Solvents. September 1993.
US Department of Energy & US Air Force, "Solvent Substitution for Pollution Prevention". Noyes Data
Corporation, Park Ridge, NJ, 1993.
USEPA, Office of Air and Radiation, Alternatives for CFC-113 and Methyl Chloroform in Metal
Cleaning, June 1991.
66
-------
USEPA, Office of Enforcement and Compliance Assurance, "Federal Facility Pollution Prevention Project
Analysts: A Primer for Applying Life Cycle and Total Cost Assessment Concepts" EPA/300/B-95/008,
July 1995. !
USEPA, OPPT, Cleaner Technologies Substitutes Assessment - Screen Printing Industry: Screen
ReclamationJBPA document # EPA744R-94-005, September 1994.
USEPA, Office of Pollution Prevention, Stakeholders' Action Agenda: A report of the workshop on
Accounting an Capital Budgeting for Environmental Costs. December 1993
USEPA, Office of Research and Development, Guide to Cleaner Technologies: Alternatives to
Chlorinated Solvents for Cleaning and Degreasing. EPA/625/R-93/016, February 1994.
USEPA, Office of Research and Development, Guide to Cleaner Techologies: Cleaning and Degreasing
Process Changes. EPA/625/R-93/017, February 1994.
USEPA, Office of Research and Development, "Demonstration of Alternative Cleaning Systems"
EPA/600/R-95/120, August 1995.
US EPA, Office of Research and Development, "Life Cycle Assessment: Inventory Guidelines and
Principles" EPA Office of Research and Development, Feb 1993, EPA/600-R-92/245
US EPA, Office of Research and Development, "Background Document on Clean Products Research and
Implementation" EPA Office of Research and Development, Oct 1990, EPA/600/2-90/048
USEPA, Office of Research and Development, "Development of a Pollution Prevention Factors
Methodology Based on Life-Cycle Assessment: Lithographic Printing Case Study".
USEPA, Office of Solid Waste and Emergency Response, "Waste Minimization in Metal Parts Gleaming".
EPA/530-SW-89-049, August 1989.
US EPA Region IH, Air, Radiation and Toxics Division, "Environmental Targeting Systems",
EPA/903/B-94/001, December 1994. '•
Vigon, Bruce "Life-Cycle Assessment" Industrial Pollution Prevention Handbook by Harry Freeman
McGraw-Hill, Inc. 1995.
Weitz, Keith et aL "Developing a Decision Support Tool for Life-Cycle Cost Assessments". Total Quality
Environmental Management, Autumn 1994, p 23-36.
i
White, A.L. & Becker, M., Total Cost Assessment: Catalyzing Corporate Self -Interest In Pollution
Prevention. Tellus Institute. May 1991. ;
White, A.L, D.E. Savage and A Dierks, Tellus Institute, Environmental Accounting Principles for the
Sustainable Enterprise. 1995 TAPPI International Environmental Conference, May 7-10.
Wolf, Katv. "The Generic Classification System: A Simplified Approach to Selecting Alternatives to
Chlorinated Solvents" Pollution Prevention Review, Winter 1993-94, p 15-29.
67
-------
Appendix A
Quality Assurance, Calibration and Sampling Methods
Quantitative QA Objectives
The determination of contaminant loading was made using a Denver Instrument Analytical Balance Model
A-250. The precision of the method was 0.1 mg and the accuracy was 0.3 mg. Completeness for the
gravimetric measurement method was 87%. A total of eight coupons were evaluated for each cleaning
trial. Seven valid determinations established the completeness objective.
Calibration Procedures and Frequency
Prior to measurements, the balance was calibrated using an internal "auto calibrate" routine using a 100 g
standard. In order to verify the autocalibration procedure, external weights were used. ASTM Class 1
standards (50,100,150, 200 g) were weighed weekly in triplicate. The accuracy value of 0.3 mg was the
allowable deviation for each standard. The allowable deviation was never exceeded during testing for this
project so corrective action was not necessary. Gravimetric measurements for each coupon were recorded
after a 30 second equilibration period on the balance. The reproducibility of the test coupon weight was
found to be ±0.1 mg.
Sampling Procedures
Sampling procedures and sample custody routines were followed as detailed in the Quality Assurance
Project Plan for Evaluation of Alternative Surface Cleaning Methods.
68
-------
J
Appendix B
TORI Surface Cleaning Laboratory Cleaner Performance Report
Norn* of deeming Product: W.R, Grace DARACLEAN 283 in low pressure spray wash
Contaminant: EAST FALLS Hydraulic Oi 8-32
Substrate Material: Carbon Steel
Cleaner Concentration Used: 5% by Volume Date: January 261995
Temperature: 133 deg.F . . Data Analyst: Donald Gartotta
Sample »/
Coupon*
45
53
58
47
25
50
42
69
Weigh! After
Precleanlng
(grams)
133.2739
132.4365
127.7429
138.9952
132.8583
127.3406
1624981
152.9144
Weight After
Contamination
(grams)
133.3026
132.4588
127.7787
139.0120
132.8789
127.3696
162.5246
152.9137*
Contaminant
Loading
(mg)
28.7
22.3
35.8
16.'8
20.6
29
26.5
0.7
Weight Attar
Cleaning Trial
(grams)
133.2749
132.4374
127.7437
138.9962
132.8594
127.3416
162.4986
152.9142
i
Weight c<
Contaminant
Removed (ma)
27.7
21.4
35
15.8
19.5
28
26
-as
Average:
Std-Oev.
N
Removal
Efficiency
(%)
96.52
98.96
97.77
94.05
94.66
96.55
98.11
96.231
1.4935
7
•Control
69
-------
Appendix B (continued)
Name of Cleaning Product: Brulin Corporation 815-GD in a low pressure spray wash
Contaminant: EAST FALLS Hydraulic CM 8-32
Substrate Material: Carbon Steel
Cleaner Concentration Used: 5% by Volume Date: January 26 1995
Temperature: 133 deg.F Data Analyst: Donald Gartotta
Sample »/
Coupon*
57
56
54
32
46
68
55
26
49
Weight Alter
Predeaning
(grams)
139.0683
162.8971
152.3015
127.4974
162.9000
183.2032
156.7402
150.6293
151.3593
Weight After
Contamination
(grams)
139.1084
162.9274
152.3015*
127.5245
162.9255
183.2203
156.7579
150.6852
151.3582*
Contaminant
Loadtog
(ma)
40.1
30.3
0.0
27.1
25.5
17.1
17.7
55.9
-1.1
Weight Alter
Cleaning Trial
(grams)
139.0710
162.8986
152.3017
127.5008
162.9014
183.2048
156.7412
150.6341
151.3584
Weight of
Contaminant
Removed (mg)
37.4
28.8
-0.2
23.7
24.1
15.5
16.7
51.1
-0.2
Average:
StdDev.
N
Removal
Efficiency
l%>
93.27
95.05
87.45
94.51
90.64
94.35
91.41
18.18
92.382
2.7268
7
•Control
Mama of Cleaning Product: Oakite Products Inpro-deon 2500 In low pressure spray wash
Contaminant: EAST FALLS Hydraulic OS 8-32
Substrate Material: Carbon Steel
Cleaner Concentration Used: 54.59 gram/gallon Date: January 261995
Temperature: 140 deg. F Dora Analyst: Donald Gartotta
Sample */
Coupon*
38
17
7
59
19
43
21
63
6
Weight After
Predeaning
(grams)
146.6888
128.3814
147.4288
137.8544
123.1852
187.5290
140.1398
150.8167
162.9305
Weight After
COfuiJI VmKliIOn
(grams)
146.7412
128.4414
147.4659
137.9248
123.1845*
187.6032
143.1390*
150.8896
162.9730
Contaminant
Uxxfng
(mo)
52.4
60
37.1
70.4
-0.7
74.2
-0.8
72.9
42.5
Weight Alter
Cleaning Trial
(grams)
146.6926
12&3857
147.4323
137.8586
123.1858
187.5349
140.1414
150.8226
162.9361
Weight of
Contaminant
Removed (mg)
48.6
55.7
33.6
66.2
-1.3
68.3
-24
67
36.9
Average:
SfeLDev.
N
Removal
Efficiency
(%)
92.75
92.03
90.57
94.03
92.C6
0
91.91
86.82
91.557
Z3431
7
"Control
70
-------
Appendix C
Case Studies Documenting Success of Closed Loop Aqueous Degroasing
The following case studies are part of a TURI technical report, Closed Loop Aqueous Cleaning.
Company B of Newton, MA is a primary metals company which processes tantalum and niobium from the
refining stage to the production of finished parts. Company B used 1,1,1-trichloroethane (TCA) in-house
for part vapor degreasing, manual sheet cleaning, and as a full strength machining coolant. The mandated
phase-out of TCA as an ozone-depleting substance in conjunction with the Labelling Law legislation
prompted this company to begin replacing TCA in 1993. TCA was replaced with oil-based lubricants for
machining processes and alkaline cleaners and non-ozone depleting solvents for cleaning processes.
Another major factor prompting the switch from TCA was the issue of worker health and safety. By
implementing these alternative technologies, Company B has eliminated approximately 40,000 pounds per
year of TCA. In addition, the use of ultrafiltration units (spiral wound and hollow fiber) on their cleaning
lines has reduced their cleaner purchases from 6,000 pounds per year to 2,000 pounds per year. The
payback period for the transition from TCA to the alternative technologies was approximately 9 months.
Company C of Worcester, MA manufactures a variety of powdered metals parts. Because of
environmental concerns with the use of vapor degreasing, the company worked on developing an
alternative cleaning method, la late 1990, they successfully implemented an aqueous-based cleaning
system that eliminated the use of perchloroethylene. In October 1994, as part of their continuous
improvement activities, they purchased an ultrafiltration unit for the recovery and recycling of their aque-
ous cleaner. This cleaner is used primarily in part deburring as a lubricant and rust inhibitor, but also re-
moves various contaminants. The closed loop cleaning system installed at Company C processes their
used plant water, and includes a settling tank, skimmer, centrifuge, and hollow fiber ultrafiltration unit By
implementing aqueous cleaning, Company C has eliminated 24,000 pounds per year of PERC. In addition,
the use of the ultrafiltration unit has decreased annual cleaner expenditures from $60,000 to about $7,500
and the daily volume of deburring effluent discharged to drain from 2,000 gallons to about 75 gallons.
The payback on the closed loop system is estimated at 2 years.
71
-------
c >
Appendix D
Pay-back Period and Net Present Value
This appendix discusses two commonly used financial indicators: pay-back period and net present value.
Pay-Back Period
A financial indicator often used by businesses is the pay-back period of an investment. Pay back period is
the cost of the initial investment (capital costs) divided by the annual savings in operating costs that 'will
result from the investment. The outcome of the calculation will be the number of years it will take the
investment to pay itself back. Most businesses have a rule-of-thumb pay-back period for investment
decision making.
The use of payback period as an indicator for investment analysis has two disadvantages. First, it does not
take cash flows after the pay-back period into account Second, pay-back period does not address the time
value of money. The value of a dollar today is normally greater than that of a dollar receivable or payable
at a later date, for at least two reasons: (1) in periods of inflation, a dollar loses its purchasing power, so a
dollar can be used to purchase more goods or services today man a year hence; and (2) a dollar held today
can be invested to earn interest or some other return. For example, a dollar invested today at 6 percent
interest will have a value at the end of one year of $1.06, thereby making it worth more than a dollar
received at the end of that year56.
Many accountants, financial managers, and financial planners have become aware of the importance of a
thorough understanding of the time value of money concept and its application hi financial planning and
decision making.
Net Present Value
To calculate the effects of time on an investment, financial indicators other than pay-back period are
required. Tune value of money analysis (here after referred to generally as present value analysis) accounts
foir the effects of time on an investment opportunity. It requires that cash received hi the future be valued
lower than cash received today. Present value calculations convert dollars spent or saved in the future into
an equivalent amount at time f=0 (usually t=Q is the present day). The unit of time for t used hi this report
is years.
This report shows the present value of an investment by comparing the annual operating costs of the new
cleaning systems to the annual operating costs for the current cleaning systems. This comparison results hi
the difference in annual operating costs, the incremental cash flow. The incremental cash flows are the
annual savings resulting from the new equipment that will be received over the economic lifetime of a
project The economic lifetime is the period of time over which the company depreciates the equipment
56 Birrer, E.G., Carrica, J.L, Present Value Applications for Accountants and Financial Planners, Quorum books, '
New York, 1990 |
72
-------
The incremental cash flow is further discounted over the period of the investment The discount rate
converts future cash flows to today's values. The discount rate should reflect the risk associated with the
investment Analysis of high-risk investments of a speculative nature therefore requires use of a discount
rate well above the essentially risk-free rates associated with savings accounts. The equation to calculate
the present value of an annuity is illustrated hi equation 1. Furthermore, the discount rate should be
reduced to include the effect of inflation unless inflation is considered separately. In this analysis, a
discount rate that reflects the expected impact of inflation is used.
Equation 1: Calculation of Present Value of an Annuity
Where PV is the
present value, CFt is the incremental cashflow in the first year (CFX in the n* year), d is the discount
rate and n is the number of time periods. _^_ __
Present value tables provide the results of the "(l+d)n" term in the equation above for different numbers of
years (n) and discount rates (d).
The incremental cash flow is likely to vary over the different years of the investment due to trends in
prices. For example, the effects of taxes on chemicals might result in increases in chemical purchase costs.
In this case the incremental cash flows of an investment with an economic lifetime of, for example, seven
years have to be discounted for each of the seven years separately. This is illustrated in equation 2. The
financial analyses hi this study were done using a spreadsheet program which allowed the effects of
increasing taxes on ozone depleting chemicals to be included.
Equation 2: Calculation of Present Value with Differing Incremental Cash Flows
CF. CF- CFn
PV=
(l+d)1 (l+d)2 (l+d)n
Where PV is the present value, CF is the annual incremental cashflow, d is the discount rate, and n is
the number of years.
To calculate the net present value, capital costs are subtracted from the present value of the future stream
of cash flows. If the net present value of a project is greater than zero, the project is financially beneficial
to the company, and the higher the number the more profitable the investment If the net present value of a
project is less man zero, it is not financially beneficial to the company. If the net present value of a project
is equal to zero, the project generates exactly the rate of return that is required by the company.
Depreciation and Income Tax
Most investments in manufacturing equipment have a useful life. At the end of their useful life, or
economic lifetime, they may have a salvage value or they may be completely worthless. Depreciation
refers to the process of allocating the purchase costs of a machine across its entire lifetime to represent the
loss of value as a result of using the machine. For reasons of practicality, this analysis calculates straight-
73
-------
• r < )
line depreciation for all options. Straight-line depreciation is calculated by simply dividing the capital cost
of the equipment by the number of years of expected lifetime minus any salvage value. This results in the
annual depreciation of equipment. For example, a company purchasing a $7,000 piece of equipment that
has a seven year lifetime could depreciate $l,000/year on the item.
Depreciation is not a true cash flow in that no revenue transfers to the company. Depreciation is deducted
from taxable income and therefore reduces the tax burden on the firm.
Taxable income, income tax and after tax cash flow are terms used to assess the effect of income tax on the
savings resulting from the investment. The taxable income flow is the operating cash flow minus the
annual depreciation. This is the amount over which businesses have to pay income tax. After tax cash
flow refers to the amount of profit remaining after taxes have been subtracted and the depreciation is added
back.
Income tax rates for corporations vary almost as much as personal income tax rates. Most businesses are
reluctant to reveal their income tax rate. Therefore, in this analysis a typical income tax rate of 40% is
used for all projects.
The following example illustrates the treatment of depreciation and income tax in the case studies in this
report:
In die case of a process that has an operating cost of $2,000/year, and a new alternative with an
operating cost of $l,000/year, the incremental cash flow, or potential savings, of the investment
will be $l,000/year. If the lifetime of the new machine is 10 years and all costs connected with
purchasing it are $1,000, the depreciation per year would be $100. This amount is then subtracted
from the operating costs for a total taxable income of $900. The corporation's tax rate, 40%, is
applied to this balance and subtracted from taxable income to obtain the net income: $900 - $360
= $540. The annual depreciation is then added to the net income to calculate a true after tax cash
flow: $540 + $100 = $640.
This example shows that the only true savings from depreciation come from the avoided tax on income
generated by the equipment These savings are generally referred to as the depreciation tax shield because
die expense shields income from taxes.
74
-------
Appendix £
Substitution Analysis Worksheet
Typical Units
Values for Values for
Current System Alternate System
Current system
Alternate system
Inventory
use
discharge to air
discharge to water
discharge to land
Ibs/tons
Ibs/tons
Ibs/tons
Ibs/tons
Areas of Concern
Q]potenttol for Inhalation
[] potential for Ingestlon
£]potential for sJdn contact
Criteria
ToxteHy
Typical Units Values for Values for Relative Hazard Change to
' Current System Alternate System H/M/L New System
i +/-
Inhalation LC50
PEL
TLV
IDLH
Resp. system Irritation
odor threshold
pprn mg/m3
ppnx mg/m3
pprn, mg/m3
ppm. mg/m3
• Y/N
ppm, mg/m3
[]potential for specific effect
Qphysteal hazards
Specific Effect*
Oral LD50 I mg/kgl
dermal Irritation
absorbed
corrosive
PH
Y/N
Y/N
Y/N
pH units
ocular Irritation
Y/NI
carcinogen
teratogen
mutagen
other specific effects
Y/N/S
Y/N/S
Y/N/S
Physical Hazards
explosivity
flam ma billy
flashpoint
LFL/UR
reactivity
noise generation
high pressure
high temperature
1.Z3.4
1.Z3.4
F/C
%
1.Z3.4
Y/N
Y/N
Y/N
c
75
-------
Appendix E (continued)
Environmental
Qpotential for release to air
[^potential for release to watei
[^potential for release to land
global warming
ozone depleting
ozone depletingpotential
ecological effects
bioconcentratlon factor
BOD half-life
hydrolysis half-life
NOEL
Landfill
TCLP
EPTox
Incineration
Recycle
Y/N
Y/N
ODS units
Y/N
min
min
mg/kg/day
Y/N
Y/N
Y/N
"
Qphyslcal/chem characteristic Characteristic*
Q regulatory issues
Regulatory
Qenergy & resources
Energy & Rctourca*
vapor pressure
vapor density
evaporation rate
boiling point
particle size
solublitv In water
specific gravity
mmHg
oir=l
ether=1
F/C
urn
mg/L
water =1
HAP
VOC
NESHAP
degradabillty
priority pollutant
OSHA carcinogen
OSHA chem specific stds
RCRA Reportable Quant.
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
non renewable
water use
energy use
Y/N
gallons/ft3
76
-------
Appendix F
Definitions of Criteria
i
Toxicity
INHALATION LC^: The calculated concentration in air that is expected to kill 50% of a group of test
animals with a single exposure (usually 1-4 hours). (A lower LCX represents a more toxic substance.)
PEL: (Permissible Exposure Limit) The limit of allowable exposure to a chemical contaminant expressed
as a time weighted average (TWA) concentration during an 8-hour work day or as a maximum
concentration never to be exceeded either instantaneously or in the short term during any maximum period
of 15 minutes. A lower PEL represents a more toxic substance.
8 HR TWA: (Time Weighted Average) The average concentration of a substance in air over the
total time of exposure, in this case expressed as an 8-hour day. (A lower 8 HR TWA represents a
more toxic substance.)
TLV: Threshold Limit Values are published by the American Conference of Governmental Industrial
Hygienists and defined as airborne concentrations under which it is believed that nearly all workers may be
repeatedly exposed day after day without adverse effects. It should be noted that a small percentage may be
effected at or below these limits due to unusual susceptibility or pre-existing conditions. A higher TLV
indicates that more of the substance may be present before adverse effects are caused.
EDLH: (Immediately Dangerous to Life or Health) This represents the maximum concentration from
which, in the event of respirator failure, one could escape within 30 minutes without a respirator and
without experiencing any escape-impairing or irreversible health effects. (A lower EDLH represents; a more
toxic substance.)
RESPIRATORY SYSTEM IRRITATION: A substance is given a yes if it has been found, in literature
references or in practice, to be an irritant of the respiratory system.
ODOR THRESHOLD: The lowest amount of a chemical substance's vapor, in air, that can be smelled.
Substances with high odor thresholds are said to have poor warning properties since they may not be
detectable by those exposed to hazardous concentrations.
ORAL LDso: A single calculated dose of a material administered by mouth in mg per kg of body weight,
expected to kill 50% of a group of test animals. (A lower LDX represents a more toxic substance.)
DERMAL IRRITATION: A substance is given a yes if it has been found, in literature references OF in
practice, to be an irritant of the skin. ,
ABSORBED: Indicates whether or not a chemical may be absorbed through the skin.
77
-------
Jfc-
CORROSIVE: Any liquid or solid with pH ranges of 2-6 or 12-14 that causes visible destruction or
irreversible alteration of living tissue, or a liquid that has a severe corrosion rate on steel.
pH: A logarithmic index for the hydrogen ion concentration in an aqueous solution. A pH below 7
indicates acidity, and one above 7 alkalinity (@ 25°C). The pH scale ranges from 0-14, with extreme
values representing a more corrosive aqueous solution. (Closer to 7 is desirable.)
OCULAR IRRITATION: Irritation caused by exposure of the eyes to a given chemical.
Specific Effects
CARCINOGEN: Any substance or combination of substances known to cause an increased incidence of
benign and/or malignant neoplasms, or a substantial decrease in the latency period between exposure and
onset of neoplasms in humans or in one or more experimental mammalian species .as the result of any oral,
respiratory or dermal exposure, or any other exposure that results in the induction of tumors at a site other
thain the site of administration. This definition includes any substance which is metabolized into one or
more potential occupational carcinogens by mammals. A substance receives a yes (Y) if it has an IARC
(International Agency for Research on Cancer) classification of 1, a suspect (S) if it has a classification of
2A or 2B, or a no (N) if it has a classification of 3 or 4.
TERATOGEN: Produces changes in the offspring of the exposed subject
MIJTAGEN: A chemical that causes mutations in the genetic material of exposed subjects.
OTHER SPECIFIC EFFECTS: Any other specific effects can be noted here, such as effects on the central
nervous system, liver or kidney.
Physical Hazards
EXPLOSrVTTY: The ease with which a material will detonate. Detonation is the extremely rapid, self-
propagating decomposition of a material accompanied by a high-pressure-temperature wave that moves at
1000-9000 meters/second. (The DOT rates explosivity on a scale of 1-4, with a higher number denoting a
greater explosion risk.)
FLAMMABILrrY: The ease with which a material will ignite spontaneously either from exposure to a
high temperature environment or to a spark or open flame. It also involves the rate of spreading of a flame
once it has started. (The DOT rates flammability on a scale of 1-4, with a higher number denoting a
greater ignition risk.)
FLASH POINT: The temperature at which material gives off vapor sufficient to form an ignitable
mixture with the air near the surface of the material. The lower the flash point, the more
probability an explosion could occur under normal working conditions. (Lower is less desirable.)
LFL/UFL: (Lower/Upper Flammable Limit) The lowest/highest concentration of gas or vapor
(percentage by volume in air) that will bum or explode when a source of ignition is present
Substances with a low LFL, as well as those with a broad flammability range, tend to represent a
greater hazard within the workplace.
REACTIVITY: Chemical reaction with the release of energy. Undesirable effects such as pressure
buildup, temperature increase, formation of noxious, toxic or corrosive by-product may occur because of
78
-------
the reactivity of a substance to heating, burning, direct contact with other materials, or other conditions in
use or in storage.
NOISE GENERATION: The amount of noise associated with the process. This category is rated yes if
either: a) workers are exposed to noise levels greater than 85 dBA; or b) plant neighbors are exposed to
noise levels above the ambient background level.
HIGH PRESSURE: If the process involves the handling of gases at pressures greater than atmospheric,
this category is rated yes. High pressure processes pose a greater risk for accidental exposures to the
chemicals under pressure.
HIGH TEMPERATURE: High temperature operations also entail a greater risk of chemical exposure, and
can lead to worker heat stress. A yes is given in this category if the process involves temperatures greater
than 100 F.
Environmental Hazards
GLOBAL WARMING: The substance is given a yes if it has been found to contribute to global wanning.
OZONE DEPLETING & OZONE DEPLETING POTENTIAL: The substance is given a yes if it has been
found to contribute to the depletion of the ozone layer. Ozone depleting potential (ODP) is reported in
OOP units; scoring is relative to CFC-11 which is 1 ODP unit
SMOG CONTRIBUTOR: The substance is given a yes if it has been found to contribute to the formation
of smog.
ECOLOGICAL EFFECTS: The substance is given a yes if it has been found to exhibit ecological effects.
BIOCONCENTRATION FACTOR: Bioconcentration is a special case of bioaccumulation in which a
dissolved substance is selectively taken up from a water solution and concentrated in body tissue by
nondietary routes. The factor is a ratio of the rate of uptake to the rate of elimination of the substance in
body tissue. (A higher factor means that the substance tends to accumulate quite readily within the body,
possibly leading to adverse health effects.)
BOD HALF-LIFE: The time required for the biochemical oxygen demand (BOD) of an organic waste to
be reduced to one half of its initial level. BOD is a measurement of the dissolved oxygen consumed by
microbial life white assimilating and oxidizing the organic matter present in the organic waste. (A waste
with a lower BOD half-life decomposes more rapidly, decreasing die time required for treatment before
discharge.) !
HYDROLYSIS HALF-LIFE: The time required for the hydrolysis potential of a substance to be reduced
to one half of its initial level. Hydrolysis is a chemical reaction in which water reacts with the substance to
form two or more new substances. (A waste with a lower hydrolysis half-life decomposes more rapidly,
decreasing the tune required for treatment before discharge.)
NOAEL: (No Observed Adverse Effect Level) Usually defined for fish, the experimental exposure level
representing the highest level tested at which no adverse effects were demonstrated. (A lower NOAEL
represents a more toxic substance.)
79
-------
C->
Release to Land ' ,„ ^
LANDFILL: The substance is given a yes if its waste is landfilled.
TCLP: (Toxicity Characteristic Leaching Procedure) The TCLP is a test to measure the
leachability of a waste. .
EPTOX: EP Toxicity procedure for testing hazardous waste, set forth in the Code of Federal
Regulations, 40 CFR Part 261 Appendix H
INCINERATION: The substance is given a yes if its waste is incinerated.
RECYCLE: The substance is given a yes if its waste is recycled.
Physical/Chemical Characteristics
VAPOR PRESSURE: The saturated partial pressure of a vapor in contact with its liquid form. The vapor
pressure increases with temperature. Substances with higher vapor pressures at a given temperature
produce higher vapor concentrations in the surrounding air, which may result in adverse health effects or
explosion hazards. (Higher is less desirable.)
VAPOR DENSITY: The weight of a vapor per unit volume at any given temperature and pressure,
relaitive to the density of air. Higher density vapors can collect near the bottom of enclosed spaces,
increasing potential exposure.
EVAPORATION RATE: The rate at which a liquid converts to a vapor at temperatures below the boiling
point. This rate increases with a rise in temperature since it depends on the saturated vapor pressure.
Liquids with higher evaporation rates tend to be lost to the atmosphere more readily, producing bom health
hazards and economic losses. (Higher is less desirable.)
BOILING POINT: The temperature at which a liquid boils when exposed to the atmosphere. At this
point, the saturated vapor pressure of a liquid equals the pressure of its surroundings. Substances with
lower boiling points tend to evaporate more quickly. (Lower is less desirable.)
PARTICLE SEE: The physical dimensions of a molecule or particle created by the process. Particles
smaller than 50 micrometers may be inhalable (i.e., deposit in the respiratory tract). (Smaller is less
desirable.)
SOLUBILITY IN WATER: The maximum number of milligrams of a substance that may be dissolved in
one liter of water.
SPECIFIC GRAVITY: The ratio of the mass of a given volume of a substance to the mass of an equal
volume of water at a temperature of 4°C. A value greater than 1 represents a substance more dense than
water. This may be important in certain aqueous cleaning applications.
Regulatory Issues
HAP: (Hazardous Air Pollutant) Air pollutants that are not covered by ambient air quality standards but
that, as defined in the Clean Air Act, may reasonably be expected to cause or contribute to irreversible
illness or death.
80
-------
T
VOC: (Volatile Organic Compound) Organic materials containing carbon and hydrogen that are subject
to rapid evaporation.
NESHAP: (National Emission Standard for Hazardous Air Pollutant) Emission standard set by the EPA
for an air pollutant not covered by National Ambient Air Quality Standards (NAAQS) that may cause an
increase in deaths or in serious, irreversible, or incapacitating illness. Primary standards are designed to
protect human health, secondary standards to protect public welfare.
DEGRADABILITY: The substance is given a yes if it degrades biologically.
PRIORITY POLLUTANT: List of 129 pollutants broken down in to the following major categories:
volatile organics, acid-extractable organics, base and neutral organics, pesticides and PCBs, metals,
cyanides and asbestos.
OSHA CARCINOGEN: Without establishing PELs, OSHA promulgated standards in 1974 to regulate the
industrial use of thirteen chemicals.
OSHA CHEMICAL SPECIFIC STANDARDS: Chemicals for which OSHA has promulgated specific
regulations.
RCRA RQ: (RCRA Reportable Quantities) A substance has a low reportable quantity when it has been
rated a more significant hazard. (Lower is less desirable.)
Energy and Resources
NON RENEWABLE: The substance is given a yes if it is derived from a non-renewable resource.
WATER USE: The amount of water used in the process is entered.
ENERGY USE: The amount of energy used in the process is entered.
81
-------
', 11
Appendix G
Substitution Analysis Worksheet - Market Forge
Areas of Concern
Typical Units
Values for . Values for
Current System Alternate System
Current system TCA degrease|
Alternate systermophtno solvent
Inventory
use
discharge to air
discharge to water
discharge to land
Ibs/tons
Ibs/tons
Ibs/tons
Ibs/tons
7145
1246
0
5899
9766
286C
C
6904
(xjpotentlol for inhalation
[^potential for Ingestton
(xj potential for skin contact
rtential for eye contact
jxjpotential for specific effects
[xjphysical hazards
Criteria
t
ToxteHy
Typical Untts Values for Values for Relative Hazard Change to
Current System Alternate System H/M/L New System
Inhalation LC50
PEL
TLV
IDLH
Resp. system Irritation
odor threshold
ppm.mg/m3
ppm,mg/m3
ppm.ma/m3
ppm.ma/m3
Y/N
ppm.ma/m3
350 ppm
1000
N
100 ppm
N
.
Specific Effect*
Physteol Hozorcte
OralLD50 | ma/kal 1
dermal Irritation
absorbed
corrosive
PH
Y/N
Y/N
Y/N
pH units
Y
N
N
N
N
N
-
ocular Irritation I Y/N
Y] N
•f
carcinogen
teratogen
mutagen
other specific effects
Y/N/S
Y/N/S
Y/N/S
S
s
S
N
N
N
H
H
H
•h
+
•f
explosMty
flashpoint
LFUUR.
reactivity
noise generation
high pressure
high temperature
^.2.ZA
1.Z3.4
F/C
%
1.Z3.4
Y/N
Y/N
Y/N
none
7.5/1Z5
N
N
Y
140
1/6
N
N
N
..
82
-------
Appendix G (continued)
[x] potential tot release to air
Q potential for release to watei
[^potential tot release to land
Environment^
global warming
ozone depleting
ozone depleting potential
ecological effects
bioconcentration factor
BOD half-life
hydrolysis half-lfe
NOEL
Landfill
TCLP
EPTox
Incineration
Recycle
Y/N
Y/N
OOS units
Y/N
mln
: min
ma/kg/day
! Y/N
Y/N
Y/N
Y
Y
N
N
+
4-
[xjphysteal/chem characteristic
CharacterWIcs
vapor pressure
vapor density
evaporation rate
boiling point
particle size
solubility in water
specific gravity
mmHg
air=l
ether=l
F/C
um
mg/L
water= 1
IX
151
165
0.4
1.34
0.5
5.4
6
350
neglgjbte
0.79
+
-
[x] regulatory issues
Bocutatofy
HAP
voc
NESHAP
dearadabitry
priority pollutant
OSHA carcinogen
OSHAchem specific stds
RCRARQ
Y/N
Y/N
Y/N
Y/N
' Y/N
Y/N
Y/N
Y/N
Y
Y
N
N
N
N
H
H
H
+
+
[xjenergy & resources
Energy ft Resources
non renewable
water use
energy use
Y/N
galons/ft3
many
Y
0
Y
0
83
-------
Appendix H
Substitution Analysis Worksheet - Company A
Typical Units
Values for Values for
Current System Alternate System
Current system TCEdegrease
Alternate plastic; blast
Inventory
use
Discharge to air
dbcharge to water
discharge to land
Ibs/tons
Ibs/tons
Ibs/tons
Ibs/tons
11,152
10.452
0
700
Areas of Concern
[xjpotentlal for Inhalation
Criteria
ToxteBy
Typical Units Values for Values for Relative Hazard Change to
Current System Alternate System H/M/L New System
Inhalation LC50
PEL
TLV
DLH
Resp. system Irritation
odor threshold
ppm, mg/m3
ppm. mg/m3
ppm,mg/m3
pprama/m3
Y/N
ppm. ma/m3
50 ppm
100
1000
' Y
[xjpotential for specific effects
[xjphysical hazards
Spocinc Effocb
Ptvy»lcol Hozardt
Ljpotentlal for ingestion
^potential for skin contact
[^potential for eye contact
OralLDSO
mg/kgl
dermal Irritation
absorbed
corrosive
PH
Y/N
Y/N
Y/N
pH units
Y
N
N
ocular irritation
Y/NI Y|
cardnogen
teratogen
mutagen
other specific effects
Y/N/S
Y/N/S
Y/N/S
S
S
S
explostvfty
(tammabilty
flashpoint
LFL/UH.
reactfvtty
note generation
Ngh pressure
Ngh temperature
1.2.3.4
1.Z3.4
F/C
*
1.Z3.4
Y/N
Y/N
Y/N
none
8/10.5
Y
N
Y
Y
84
-------
Appendix H (Continued)
Environmental
(x[potentlol for release to air
Q potential for release to watei
[x] potential for release to land
global warming
ozone depleting
ozone depleting potential
smog contributor
ecological effects
bloconcentration factor
BOD half-life
hydrolysis half-life
NOEL
Landfill
TCLP
EPTox
Incineration
Recycle
Y/N
Y/N
ODS units
Y/N
Y/N
mln
min
mg/kg/day
Y/N
: Y/N
Y/N
N
N
Y
N
Y
[xjphystaol/chem characteristic
Characteristics
vapor pressure
vapor density
evaporation rate
boiling point
particle size
solubility In water
specific gravity
mmHg
dir=l
ether=l
F/C
: urn
man.
water «1
58
4.53
6.39
189
0.1
1.46
|x| regulatory teues
Raoufcrhxy
HAP
VOC
NESHAP
degradability
priority pollutant
OSHA carcinogen
OSHA chem specific stds
RCRARQ
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y
Y
(xjenergy & resources
Energy & Resources
non renewable
water use
energy use
Y/N
gallons/ft3
Y
0
85
-------
Appendix H (continued)
Areas of Concern
rtentiol for inhalation
[^potential foringestion
Q] potential for skin contact
[^potential for eye contact
[x]potential for specific effects
[xjphysical hazards
Current system TCE decrease
Attemate CO2
Typical Units
Values for Values for
Current System Alternate System
Inventory
use
discharge to air
discharge to water
discharge to land
Ibs/tons
Ibs/tons
Ibs/tons
Ibs/tons
11,152
10.452
0
700
Criteria Typical Units Values for Values for Rotative Hazard Change to
Current System Alternate System H/M/L New System
Inhalation LC50
PEL
TtV
IDLH
Resp. system irritation
odor threshold
ppm.mg/m3
ppnxmg/m3
ppm.mg/m3
pcmmg/m3
Y/N
ppm.mg/m3
SOppm
100 ppm
lOOOppm
V
5000 ppm
5000 ppm
asphyxiant
CrolLDSO
mg/kal
dermal Irritation
absorbed
corrosive
PH
ocular Irritation
Y/N
Y/N
Y/N
pH units
Y
N
N
Y/NI Y
Y
Nl
Specific Effoch
carcinogen
teratogen
mutaaen
other specific effects
Y/N/S
Y/N/S
Y/N/S
S
S
S
N
exp
N
explostvffy
flammabilty
flashpoint
La/ua
reactivity
noise generation
high pressure
hiah temperature
1.23.4
1.23.4
F/C
%
1,23.4
Y/N
Y/N
Y/N
none
8/10.5
Y
N
Y
Y
N
86
-------
Appendix H (continued)
[x]potential for release to air
[] potential for release to water
|xj potential for release to land
Environmental
global warmlna
ozone depleting
ozone depleting potential
smog contributor
ecological effects
bloconcentratlon factor
BOO half-life
hydrolysis half-life
NOEL
landfill
TCLP
EPTox
Incineration
Recycle
Y/N
( Y/N
ODS units
Y/N
. Y/N
min
• min
ma/kg/dav
Y/N
Y/N
Y/N
N
N
Y
Y
Y
N
N
N
[x]phvslcol/chem characteristic ChotacterbHc*
[x] regulatory Issues
[x]energy & resources
vapor pressure
vapor density
evaporation rate
boiling point
particle size
solubilty in water
specific gravity
mm Ha
a)r=l
ether=l
F/C
um
moA
water«l
58
4.53
6.39
189
0.1
1.46
Regulatory
HAP
VOC
NESHAP
dearadabfllry
priority pollutant
OSHA carcinogen
OSHA chem specific stds
RCRARQ
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y
Y
N
N
Energy ft Resource*
non renewable
water use
energy use
! Y/N
aalions/ft3
Y
0
N
0
87
-------
I iff-»
Appendix H (continued)
Areas of Concern
Typical Units
Values for Values for
Current System Alternate System
Current system
Alternate
TCEdegrease
aqueous
Inventory
use
oTscharae to air
cSscharae to water
discharge to land
Ibs/tons
Ibs/tons
Ibs/tons
tos/tons
11.152
10.452
0
700
Criteria Typical Units Values for Values for Relative Hazard Change to
Current System Alternate System H/M/L New System
tential for inhalation
ToxJcltv
Inhalation LC50
PEL
TLV
IDLH
Resp. system irritation
odor threshold
ppm mg/m3
ppm, mg/m3
ppra mg/m3
ppm. mg/m3
Y/N
ppra mg/m3
50 ppm
100 ppm
1000 ppm
Y
5mg/m3
Y
Q potential for Ingestion
jxjpotential for skin contact
[xjpotential for specific effects
[xjphysical hazards*
OalLDSO
absorbed
PH
Y/N
Y/N
Y/N
pH units
Y
N
N
Y
ocular irritation
Y/Nl Y
Specie Effect*
carcinogen
teratogen
mutagen
other specific effects
Y/N/S
Y/N/S
Y/N/S
S
S
S
Physical Hazard!
explosMty
flam ma bitty
flashpoint
LFUUR
reactivity
noise generation
high pressure
Nan temperature
1.Z3.4
1.Z3.4
F/C
%
1.Z3.4
Y/N
Y/N
Y/N
none
8/10.5
Y
N
Y
Y
88
-------
Appendix H (continued)
[xjpotenrlot for release to air
*
[x]potential for release to watei
[xjpotenttal for release to land
Environmental
global warming
ozone depleting
ozone depleting potential
smog contributor
ecological effects
bloconcentration factor
BOD half-life
hydrolysis half-life
NOEL
Landffll
TCLP
EPTox
Incineration
Recycle
1 Y/N
Y/N
OOS units
Y/N
Y/N
min
min
mg/kg/day
Y/N
Y/N
Y/N
N
N
Y
N
Y
possible
[x]physlcal/cnem characteristic
[xjregutatory Issues
[xjenergy & resources
Characteristics
vapor pressure
vapor density
evaporation rate
boiling point
particle size
soiubllty in water
specific gravity
mmHg
air-1
ettier=l
F/C
um
mg/L
water » 1
58
4.53
6.39
189
0.1
1.46
Regulatory
HAP
voc
NESHAP
degradablllty
priority pollutant
OSHA carcinogen
OSHA chem specific stds
RCRARQ
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
, Y/N
Y/N
Y
Y
N
N
Energy ft Roiourcat
non renewable
water use
energy use
Y/N
gallons/ft3
Y
0
89
-------
* •** * * if
Appendix I
Information Resources !
U.S. Department of Health and Human Services, Centers for Disease Control, NIOSH Pocket Guides to
Chemical Hazards. June 1990. This publication is for sale by the Superintendent of Documents, U.S; !
Government Printing Office, Washington, D.C. 20402.
Lews, Richard Sr., "Hazardous Chemicals Desk Reference". Third Edition, Van Nostrand ReinholdL, New ,
York, 1993. !
Government Institutes, Inc. "Book of Lists for Regulated Hazardous Substances". 1994. The address is 4
Research Place, Suite 200, Rockville, MD 20850.
90
-------
Appendix J
Annotated List of Substitution Analysis References
"Chemical Hazard Evaluation for Management Strategies: A Method for Ranking and Scoring Chemicals
by Potential Human Health and Environmental Impacts" Center for Clean Products and Clean
Technologies, University of Tennessee, EPA Document EPA/600/R-94/177, June 1994. This model uses
risk-based chemical ranking an scoring combining the toxic effects of chemicals and the potential for
exposure to those chemicals. The report ranks 140 TRI chemicals based on 99% of total releases. The
method does not include secondary global impacts such as ozone depleting and global warming.
Potential uses of the methodology are: priority setting for regulatory action, for business decisions and to
set priorities for pollution prevention. The model does not include safety issues in its analysis.
TURI
"The Role of Risk in Chemical Substitution Decisions" George Gray and Jennifer Hartwell, Harvard
Center for Risk Analysis, Harvard School of Public Health, prepared for TURI, July 1994. Outlines a risk-
based substitution decision-making framework, the chemical substitution tree (CST). Suggests looking at
both the application exposure and the disposal exposure for potential effects on the environment, workers
and the public. Gives some ideas of the actual chemical characteristics to consider and where to find
relevant information. The model seeks to identify areas of potentially high risk so that companies can
make informed decisions on how to reduce the risk.
"Blanket Wash Technology Study: An Evaluation of Commercially Available Blanket Washes" TURI
Technical Report No. 16,1994. This study gives comparative information on the perfomance,
environmental, health and safety characteristics ofblaket washes commonly uised in sheetfed offset
lithography. Each attribute was given a good, fair or poor score. The attributes scored that did not have
to do with performance included VOC content, flash point, health hazard and potential regulatory impact.
For determining a score for the health hazard, mixtures were given the highest score of any ingredient
and data were obtained from REPROTEXT. For determining the potential regulatory impact, chemicals
were given scores based on how many times they appeared on nineteen regulated chemical lists.
EPA
"Life Cycle Assessment: Inventory Guidelines and Principles" EPA Office of Research and Development,
Feb 1993, EPA/600-R-92/245 1) Goal Definition 2) Scoping - must be constantly reviewed and redefined
when necessary 3) Assumptions must be clearly stated. 4) Any interpretation beyond the "less is best"
approach is subjective. 5) Generic data may mask technologies that are more environmentally
burdensome or may not allow opportunities to identify specific facilities operating in a more
environmentally sound manner. Three components of a life cycle assessment: 1. Inventory Analysis -
the identification and quantification of energy and resource use and environmental releases to air, water,
and land. 2. Impact Analysis - the technical qualitative and quantitative characterization and assessment
of the consequences on the environment. During this analysis, linkages are established between products
-------
and potential impacts (sulfur dioxide and the loss of biodiversity) 3. Improvement Analysis - the
evaluation and implementation of opportunities to reduce environmental burdens Raw material
acquisition. Materials Manufacture, Product Fabrication, Consumption, Waste Management,
Transportation 5
"Background Document on Clean Products Research and Implementation" EPA Office of Research and
Development, Oct 1990, EPA/600/2-90/048
Criteria that have been used to evaluate products:
recycled content
recyclability/reusability
degradability
hazardous/toxic material content
water pollution impacts
soil pollution impacts
air pollution impacts
noise pollution impacts
production processes used
use of resources (including energy)
other criteria
use of more benign products/processes
general requirement of safety, usability
amount or type of packaging
provision of information for the consumer
overall corporate reputation
effect on rainforest
longer lasting or repairable products
•weight or volume contribution to landfills or waste streams
disposal problems
Methodologies that have been used to evaluate products:
product life cycle analysis
matrix approach
weighting systems
EPA, OPPT, Cleaner Technologies Substitutes Assessment - Screen Printing Industry: Screen
Reclamation. EPA document # EPA744R-94-005, September 1994. This is an in-depth risk-based
assessment of the environmental impacts, energy use, health and safety issues of the alternatives for screen
reclamation in the printing industry. This work is based on earlier work by the University of Tennessee
Center for Clean Products and Clean Technologies. This document is not intended to easily enable small-
medium sized businesses to choose among alternatives.
EPA, ORD, "Development of a Pollution Prevention Factors Methodology Based on Life-Cycle
. Assessment: Lithographic Printing Case Study". EPA document # EPA/600/R-94/157, January 1994.
This report discusses a P2 factors methodology that can be used as a screening tool to provide direction
in selecting P2 activities that provide the most environmental improvement. The tool uses a scoring
criteria using numbers 1-9. Scorings were tabulated for the following categories: energy use, airborne
emissions, waterborne emissions, photochemical oxidant creation potential, inhalation toxicity, ozone
depleting potential, global warming potential. The tool was used for two specific situations in this report:
92
-------
solvent substitution in blanket and press wash and waterless versus conventional dampening fountain
system printing.
Stephen, David, Robert Knodel and James Bridges, "A "Mark I" Measurement Methodology for Pollution
Prevention Progress Occurring as a Result of Product Design Decisions". USEPA RREL, November 1994.
This is a methodology for assessing progress in pollution prevention that results from product redesign,
reformulation or replacement. Impacts assessed are: human health, use impairment (for each media) and
disposal capacity. Note that amounts of pollutants only are assessed, not risk, (Risk may be included in
future versions.) •
EPA Region HI, Air, Radiation and Toxics Division, "Environmental Targeting Systems", EPA/9037B-
94/001, December 1994. This document reviews several existing targeting systems including five systems
for analyzing comparative risk. The following models are described: Comparative Risk Analysis, Cross-
Media Comparative Risk Assessment Model, Graphical Exposure Modeling System, Integrated
Environmental Management Program, Region VI Human Health Risk Index.
SETAC
"A Technical Framework for Life-Cycle Assessment". SETAC, January 1991.
Inventory, Impact, Improvement '.
Energy, material, environmental release data AND ecological impacts, site selection, habitat alteration,
community relations, public perceptions, good management practices, worker health concerns, public
health and accident risk.
"A Conceptual Framework for Life-Cycle Assessment". SETAC, March 1993. Presents framework for
assessing ecological and human health impacts and resource depletion using an impact analysis matrix.
The matrix uses scores from -1 to +1 and — and ++for accenting positives and negatives.
Tellus
Shapiro, Karen, "To Switch or not To Switch: A Decision Framework for Chemical Substitution" Pollution
Prevention Review, Winter 1993-94. This article outlines a method for assessing chemical substitutes
designed for use by businesses and regulators. This decision framework is to be used as an organizing
tool for assessing the desirability of substitutes. The model takes into account technical, economic,
environmental, health and safety effects. No detail is provided on how to assess the environmental, health
and safety effects or how to compare alternatives. ',
RTI, North Carolina & Battelle
Weitz, Keith et al. "Developing a Decision Support Tool for Life-Cycle Cost Assessments". Total Quality
Environmental Management, Autumn 1994, p 23-36. this method is intended to enhance life cycle
assessment by adding cost information. It contains a concise history ofLCA. It defines three life cycle
cost categories: conventional, liability and environmental. The authors suggest including such
environmental costs as global warming and ozone depletion. It contains a table of the costs considered by
various costing methodologies. It discusses a "top-down" approach to modeling to facilitate cost effective
decision making, (ie. begin by viewing the project in a generic life-cycle context before gathering cost and
environmental data and adding detail as needed.)
93
-------
Institute for Research and Technical Assistance
Wolf, Katv. "The Generic Classification SyStern: A Simplified Approach to Selecting Alternatives to
Chlorinated Solvents" Pollution Prevention Review, Winter 1993-94, p 15-29.
The author sets up a generic classification system for choosing alternative to a chlorinated solvent. The
properties/classifications of PEL, VOC, HAP, flash point, evaporation rate, solvent strength, ozone
depleting potential, global warming potential and toxicity are covered. Good reference for data on the
available solvent alternatives. Methodology is practical but very specific to solvents alternatives.
Air Force, Navy, DOE
Tiley, Jaimie, "Solvent Substitution Methodology using Multiattribute Utility Theory and the Analytical
Hierarchical Process". Department of the Air Force, Air Force Institute of Technology, Wright-Patterson
Air Force Base, OH. This thesis presents a multicriteria decision making methodology for ranking
alternatives to solvent cleaning. It compares Multiattribute Utility Theory and the Analytical Hierarchical
Process. The cleaning situation studied is general cleaning of aircraft engine components. There were
problems associated with both decision models including independence constraints and scaling issues.
The author used group decision making scoring (1-7) in four areas: environmental impact, health/safety,
process compatibility, cleaning effectiveness. Important attributes within each category were chosen by
survey. Interesting to note which attributes were chosen in the environmental impact and health/safety
categories (p 46.)
"Hazardous Material Life-Cycle Cost Model" L.A. Hermansen et aL, Naval Health Research Center,
Technical Document 93-4D. This is a user's manual for the software. The model includes five phases:
r&d, acquisition, construction, maintenance/repair and final disposition and looks at the probability for
no exposure, above PEL for personal exposure, and unacceptable environmental exposure. The following
cost factors are used: claims and compensation, disposal, engineering controls, fines and penalties,
medical surveillance, medical treatment, permits and certification, personal protective equipment,
procurement, spill containment andcleanup, storage, training, and workplace monitoring.
Booth, Steven, Linda Trocki and Laura Bowling, "A Standard Methodology for Cost-Effectiveness
Analysis of New Environmental Technologies". Los Alamos National Laboratory, June 22,1993. This
methodology is used to assess the cost-effectiveness of environmental technologies under development.
The steps of the methodology are: define the technologies, define the system, characterize the performance
(minimum exposure to hazardous materials is included here) and develop life-cycle cost of alternatives.
Uncertainty and environmental risk are included. Tailored for use on evaluation of remediation
technologies. Not practical for small-med business decision making use.
Other
"The Haze Around Environmental Audits" Technology Review, April 20,1992.
Environmental audits - cradle to grave analyses
"it makes more sense to do the studies within a given industry an limit analysis to which product or
process uses less material and energy and, therefore, is environmentally more benign.
Pekelney, David, "Analyzing Environmental Policies for Chlorinated Solvents with a Model of Markets
and Regulations". A RAND Graduate School Dissertation, November 1990. This report presents a model
of chlorinated solvent markets and regulations. The model gives possible outcomes of specific policy
decisions concerning the solvents. Good background of solvent market at that time.
94
-------
Keoleian, Gregory A. "Pollution Prevention Thronph Life-Cvcle Design" Industrial Pollution Prevention
Handbook by Harry Freeman McGraw-Hill, Inc. 1995.
Product Life Cycle can be organized into the following stages:
Raw material acquisition '.
Bulk material processing
'Engineered and specialty materials production
manufacturing and assembly
Use and service
Retirement '
Disposal
Environmental requirements should be developed to minimize:
Use of natural resources (particularly nonrenewables)
Energy consumption ^
Waste generation
Health and safety risks
Ecological degradation '
Jacobs Engineering Group. "Source Reduction and Recycling of Halogenated Solvents: Life-Cvcle
Inventory and Tradeoff Analysis". 1992. This report examines the tradeoffs of the substitution of aqueous
cleaning for vapor degreasing and supercritical CO2 paint spraying for traditional airless paint spraying.
First a lifecycle inventory was taken then the results used to develop a framework for impact comparison
and tradeoff analysis. This report describes the Impact Analysis Matrix which is defined by five categories
of resource utilization and emission parameters (material inputs, energy inputs, atmospheric emissions,
aqueous wastes and solid wastes) and seven categories of environmental impact or risk areas (global
warming, ozone depletion potential, non-renewable resource utilization, air quality, water quality, land
disposal and transportation effect). Results of the analyses are dependent on the scope of the lifecycle
inventory.
Grimsted, Bradley, et al., "A Multimedia Assessment Scheme to Evaluate Chemical Effects on the
Environment and Human Health" Pollution Prevention Review, Summer 1994, pp. 259-268.
This article presents a model for calculating a common unit of measure - the Pollution Unit - that allows
comparisons of potential relative effects of chemicals on cofferent environmental media. The scheme that
is presented incorporates environmental and human health factors (using ambient standards and
regulatory criteria) but can be adjusted to stress one over the other or may be developed to incorporate
occupational standards if worker health is of primary concern. Authors boast easy to use, technically
defensible and versatile as words to describe the model. Ease of use must depend on the sophistication of
the person using it. The model does not seem practical for small businesses.
Baumann, Henrikke and Tomas Rydberg, "Life Cycle Assessment: A Comparison of Three Methods for
Impact Analysis and Evaluations" Journal of Cleaner Products, Volume 2, Number 1,1994, pp. 15-20.
This paper evaluates three methods for impact analysis and evaluation for comparing different types of
emissions: the exological scarcity method, the environmental theme method and the environmental
priority strategies in product design method. The goal of each method is to set a one dimensional value
on resource use and emissions in order to calculate the total environmental impact of a product.
95
------- |