ALLIANCE
Technologies Corporation

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                                          GCA-TR-CH-83-06
    U.S.  ENVIRONMENTAL PROTECTION AGENCY
                Chemical  Unit
Integrated Environmental  Management Project
  Office of Policy and Resource Management
            Washington, DC  20460
           Contract No.  68-02-3168
             Task Nos.  54 and 96
              EPA Task Manager
               Arnie Edelman
      PRELIMINARY ANALYSIS OF POSSIBLE
   SUBSTITUTES FOR 1,1,1-TRICHLOROETHANE,
     TETRACHLOROETHENE,  DICHLOROMETHANE,
    TETRACHLOROMETHANE,  TRICHLOROETHENE,
        AND TRICHLOROTRIFLUOROETHANE
               Final Report
                 May 1983



                Prepared by
               Richard Rehm
            Elizabeth Anderson
              Samuel Duletsky
               Terry 0'Brian
               Hugh Rollins
               GCA Corporation
           GCA/Technology Division
      Chapel Hill, North Carolina  27514

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This report was furnished to the U.S.  Environmental  Protection Agency by GCA
Corporation, GCA/Technology Division,  in fulfillment of Contract No.  68-02-3168,
Task Order Nos. 54 and 96.   The contents of the report do not necessarily
reflect the views and policies of the  Environmental  Protection Agency, nor
does mention of trade names or commercial products constitute endorsement or
recommendation for use.

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                                    ABSTRACT


     This document investigates the technical  and economic feasibility of
substitution for six halogenated industrial  solvents used in four source
categories.  The solvents  investigated are 1,1,1-trichloroethane,
tetrachloroethene (perchloroethylene), dichloromethane (methylene chloride),
tetrachloromethane (carbon tetrachloride), trichloroethene, and
trichlorotrifluoroethane (chlorofluorocarbon 113).  The four source categories
investigated are metal  cleaning, dry cleaning,  surface coatings,  and fabric
scouring.

     The six halogenated solvents listed above are often used because their
physical and chemical properties make them unique in given situations.  Thus,
it should be noted that substitution may not always be feasible.   Substitution
should always be determined on a case-by-case basis.
                                       m

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                                TABLE  OF  CONTENTS
LIST OF FIGURES	      ix

LIST OF TABLES	      x

1 .0  INTRODUCTION AND SUMMARY	       1-1
1 .1  PURPOSE AND SCOPE	       1-1
1 .2  METHODOLOGY	       1-3

     1.2.1    Description	       1-3
     1.2.2    Limitations	       1-3

1.3  SUMMARY OF FINDINGS	       1-4

     1.3.1    Metal  Cleaning	       1-4
     1.3.2    Dry Cleaning	       1-6
     1.3.3    Surface Coating	       1-7
     1.3.4    Fabric Scouring	       1-8

1 .4  RECOMMENDATIONS FOR FUTURE STUDY	       1-9

     1.4.1    Metal  Cleaning	       1-10
     1.4.2    Dry Cleaning	       1-11
     1.4.3    Surface Coating	       1-11
     1.4.4    Fabric Scouring	       1-11

1.5  REFERENCES	       1-12

2.0  METAL  CLEANING	       2-1
2.1  GENERAL DESCRIPTION OF USE	       2-1

     2.1.1    Industry Characterization	       2-1
     2.1.2    Process Description	       2-2

2.2  SELECTION OF CLEANING METHODS	       2-6
2.3  TECHNICAL ANALYSIS OF SUBSTITUTES	       2-9

     2.3.1    Aqueous Cleaning	       2-9

             2.3.1.1   Process  Description	       2-9
             2.3.1.2   Method of Substitution	       2-11
             2.3.1.3   Degree of Substitution	       2-13
             2.3.1.4   Resource Availability	       2-18
                                     IV

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                          Table of Contents  (con't.)


                                                                     Page

     2.3.2   Emulsion  Cleaning	       2-18

             2.3.2.1    Process Description	       2-18
             2.3.2.2    Method of Substitution	       2-19
             2.3.2.3    Degree of Substitution	       2-20
             2.3.2.4    Resource Availability	       2-23

     2.3.3   Nonchemical  Cleaning	       2-23

             2.3.3.1    Process Description	       2-23
             2.3.3.2    Method of Substitution	       2-24
             2.3.3.3    Degree of Substitution	       2-24
             2.3.3.4    Resource Availability	       2-25

     2.3.4   Cleaning  with Other Organic Solvents	       2-26

             2.3.4.1    Process Description	       2-26
             2.3.4.2    Method of Substitution	       2-26
             2.3.4.3    Degree of Substitution	       2-29
             2.3.4.4    Resource Availability	       2-34

2.4  ECONOMIC ANALYSIS OF SUBSTITUTES	       2-34

     2.4.1   Background	       2-34

             2.4.1.1    Industry Structure	       2-35
             2.4.1.2    Market Share of Substitutes	       2-35
             2.4.1.3    Growth Trends	       2-38

     2.4.2   Product  Quality	       2-41

             2.4.2.1    Cold Cleaning with Halogenated Solvents
                       Versus Al ternati ves	       2-41
             2A.2.2    Vapor Degreasing Versus Alternatives	       2-42

     2.4.3   Capital  and Annualized Operating Costs	       2-43

             2.4.3.1    Alternatives to Cold  Cleaning With
                       Halogenated Solvents	       2-43
             2.4.3.2    Vapor Degreasing and  Alternatives	       2-44

2.5  CONCLUSIONS AND  RECOMMENDATIONS	       2-50

2.6  REFERENCES	       2-53

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                          Table of Contents (con't.)
3.0  DRY CLEANING INDUSTRY	       3-1
3.1  GENERAL DESCRIPTION OF USE	       3-1

     3.1.1   Process Description	       3-1
     3.1.2   Industry Characterization	       3-2

3.2  DISCUSSION OF SUBSTITUTES	       3-7
3.3  TECHNICAL ANALYSIS OF SUBSTITUTES	       3-8

     3.3.1   Method of Substitution	       3-8
     3.3.2   Impact of Fire Codes on Substitution	       3-9
     3.3.3   Degree of Substitution	       3-11
     3.3.4   Resource Availability	       3-12

3.4  ECONOMIC ANALYSIS OF SUBSTITUTES	       3-14

     3.4.1   Product Quality	       3-14

             3.4.1.1   Cleanliness	       3-16
             3.4.1.2   Timeliness	       3-16
             3.4.1.3   Damage	       3-16

     3.4.2   Capital and Annualized Costs of Substitution	       3-16

             3.4.2.1   Model Plant Parameters	       3-17
             3.4.2.2   Capital Costs	       3-17
             3.4.2.3   Annualized Operating Costs	       3-23
             3.4.2.4   Costs of Fire and Boiling Code
                       Compliance	       3-28

3.5  CONCLUSIONS	       3-29

3.6  REFERENCES	       3-30

4.0  SURFACE COATINGS	       4-1

4.1  GENERAL DESCRIPTION OF SUBSTITUTES	       4-1

4.2  TECHNICAL ANALYSIS OF SUBSTITUTES	       4-2

     4.2.1   Aerosol Paints	       4-2

             4.2.1.1   Substitutes	       4-3
             4.2.1.2   Effect of Solvent Substitution on
                       Product Quality	       4-7
             4.2.1.3   Resource Availability	       4-7

                                    vi

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                          Table of Contents (con't.)

                                                                     Page

     4.2.2   Traffic Paints	       4-7

             4.2.2.1   Substitutes	       4-8
             4.2.2.2   Effect of Substitutes on Product
                       Quality	       4-8
             4.2.2.3   Resource Availability	       4-10

4.3  ECONOMIC ANALYSIS OF SUBSTITUTES	       4-10

     4.3.1   Industry Structure	       4-10
     4.3.2   Market Penetration of Substitutes	       4-12
     4.3.3   Industry Trends	       4-12
     4.3.4   Product Quality	       4-15
     4.3.5   Capital and Annualized Operating Costs	       4-15

4.4  CONCLUSION	       4-17

4.5  REFERENCES	       4-20

5 .0  FABRIC SCOURING	       5-1

5.1  GENERAL DESCRIPTION OF USE	       5-1

     5.1.1   Process Description	       5-1

5.2  DESCRIPTION OF SUBSTITUTES	       5-2
5.3  TECHNICAL ANALYSIS OF SUBSTITUTES	       5-3

     5.3.1   Method of Substitution	       5-4
     5.3.2   Degree of Substitution	       5-4
     5.3.3   Resource Availability	       5-6

5.4  ECONOMIC ANALYSIS OF SUBSTITUTES	       5-7

     5.4.1   Industry Structure	       5-7
     5.4.2   Market Penetration of Substitutes	       5-7
     5.4.3   Growth Trends	       5-11
     5.4.4   Product Quality	       5-11
     5.4.5   Capital and Annualized Cost of Substitution	       5-11

             5.4.5.1   Model Plant Parameters	       5-12
             5.4.5.2   Capital Costs	       5-12
             5.4.5.3   Annualized Costs	       5-12

5 .5  CONCLUSIONS	       5-16

5 .6  REFERENCES	       5-18
                                    VI 1

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                          Table of Contents (con't.)

                                                                     Page

APPENDIX A   COMMENTS BY E.I. DU PONT DE NEMOURS AND COMPANY..       A-l

APPENSIX B   COMMENTS BY THE HALOGENATED CLEANING SOLVENT
             ASSOCIATION	       B-l
                                   vm

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                                 LIST OF FIGURES


                                                                      Page

FIGURE 2-1      MARKET SHARE OF METAL CLEANING TECHNIQUES	      2-37

FIGURE 3-1      PERCHLOROETHYLENE DRY CLEANING PLANT FLOW
               DIAGRAM	      3-4

FIGURE 3-2      PETROLEUM SOLVENT DRY CLEANING PLANT FLOW
               DIAGRAM	      3-5

FIGURE 5-1      CONTINUOUS SOLVENT SCOURING RANGE	      5-3

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                                 LIST OF  TABLES
TABLE 2-1       SOLVENT CONSUMPTION IN COLD CLEANING AND
               VAPOR DECREASING,  MG/YR	

TABLE 2-2       ESTIMATED NUMBER OF ORGANIC SOLVENT CLEANERS
               BY SIC CODE (1980)	

TABLE 2-3       USE OF SOLVENT AND ALKALINE CLEANING SYSTEMS
               BY SIC CODE, 1976	

TABLE 2-4       COMMON METAL CLEANING SOLVENTS	

TABLE 2-5       SUMMARY OF CERTAIN CALIFORNIA INDUSTRIES USING
               SOLVENT CLEANING OPERATIONS	

TABLE 2-6       NATIONAL DECREASING SOLVENT CONSUMPTION	

TABLE 2-7       GROWTH TREND FOR DECREASING FOR SELECTED
               INDUSTRY GROUPS	

TABLE 2-8       COMPARISON OF COSTS FOR VAPOR DECREASING AND
               ALKALINE WASHING ($)	

TABLE 2-9       COMPARISON OF COSTS FOR CONVEYORIZED DECREASING
               AND ALKALINE WASHING ($)	

TABLE 2-10     COST COMPARISON BASED ON ACTUAL DATA:  VAPOR
               DECREASING VERSUS ALKALINE WASHING (Cost per
               thousand square feet)	

TABLE 2-11     COMPARISON OF COSTS FOR VAPOR DECREASING AND
               EMULSION CLEANING ($)	

TABLE 3-1       PHYSICAL PROPERTIES OF PETROLEUM DRY
               CLEANING SOLVENTS	

TABLE 3-2      ESTIMATED NUMBERS OF DRY CLEANING OPERATIONS
               AND SOLVENT USAGE IN THE UNITED STATES	

TABLE 3-3      SUMMARY OF MAJOR NFPA FIRE CODE RECOMMENDATIONS
               FOR THREE TYPES OF DRY CLEANING PLANTS	

TABLE 3-4      ESTIMATED U.S. PRODUCTION CAPACITY FOR
               PETROLEUM DRY CLEANING EQUIPMENT	,

TABLE 3-5      PERCHLOROETHYLENE MODEL PLANT PARAMETERS	
Page


2-3


2-4


2-14

2-31


2-36

2-39


2-40


2-45


2-46



2-48


2-49


3-3


3-6


3-10


3-15

3-18

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                             List of Tables (con't.)
TABLE 3-6      PETROLEUM MODEL PLANT PARAMETERS	

TABLE 3-7      CAPITAL COSTS FOR CONVERTING A SMALL
               COMMERCIAL MODEL PLANT TO PETROLEUM SOLVENT	

TABLE 3-8      CAPITAL COST OF CONVERTING A LARGE COMMERCIAL
               MODEL PLANT TO PETROLEUM SOLVENT	

TABLE 3-9      CAPITAL COSTS FOR CONVERTING AN INDUSTRIAL MODEL
               PLANT TO PETROLEUM SOLVENT	

TABLE 3-10     COMPARATIVE ANNUALIZED OPERATING COSTS OF USING
               PETROLEUM SOLVENT AND PERC IN A SMALL COMMERCIAL
               MODEL PLANT	

TABLE 3-11     COMPARATIVE ANNUALIZED OPERATING COSTS OF USING
               PETROLEUM SOLVENT AND PERC IN A LARGE COMMERCIAL
               MODEL PLANT	

TABLE 3-12     COMPARATIVE ANNUALIZED OPERATING COSTS OF USING
               PETROLEUM SOLVENT AND PERC IN AN INDUSTRIAL
               MODEL PALNT	

TABLE 4-1      POTENTIAL SOLVENT SUBSTITUTES FOR METHYLENE
               CHLORIDE IN AEROSOL PAINTS	

TABLE 4-2      POTENTIAL SOLVENT SUBSTITUTES IN TRAFFIC PAINT...

TABLE 4-3      1979 PRODUCTION OF SURFACE COATINGS	

TABLE 4-4      1980 PROFILE:  PAINTS AND ALLIED PRODUCTS	

TABLE 4-5      GEOGRAPHICAL DISTRIBUTION OF PAINT PLANTS	

TABLE 4-6      PAINTS AND ALLIED PRODUCTS:   TRENDS AND
               PROJECTIONS 1975-81	

TABLE 4-7      PRICES OF SOLVENTS	

TABLE 5-1      EXAMPLES OF OIL REMOVAL EFFICIENCIES FOR CFC-113.

TABLE 5-2      KNIT FABRIC MILLS:  TRENDS AND PROJECTIONS
               1975-80	
Page

3-19


3-20


3-21


3-22



3-25



3-26



3-27


4-5

4-9

4-11

4-13

4-14


4-16

4-18

5-5


5-8

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                             List of Tables (con't.)
TABLE 5-3      GEOGRAPHICAL DISTRIBUTION OF WET PROCESSING

TABLE 5-4
TABLE 5-5
TABLE 5-6
TABLE 5-7
TEXTILE MILLS 	
PRODUCTION CAPACITY OF PROCESSING MILLS 	 ,
CAPITAL COSTS FOR CONTINUOUS AQUEOUS
SCOURING FACILITY 	
COMPARATIVE ANNUALIZED COSTS OF CONTINUOUS
AQUEOUS AND SOLVENT SCOURING 	 ,
COMPARATIVE ANNUALIZED COSTS OF CONTINUOUS
AQUEOUS AND SOLVENT SCOURING 	
5-9
5-10
5-13
5-14
5-15

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                             ACKNOWLEDGMENT
     The authors wish to gratefully acknowledge Ms.  Virginia Steiner of
EPA's Office of Solid Waste, Mr.  Arnie Edelman of EPA's Integrated
Environmental Management Project, Ms.  Margo Og6 of EPA's Office of Toxic
Substances, and Mr.  David Patrick of EPA's Office of Air Quality Planning
and Standards for their extensive review, comments,  and technical  advice
during each stage in the development of this document.

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                       1.0  INTRODUCTION AND SUMMARY

1.1  PURPOSE AND SCOPE
     This report presents a preliminary analysis of the technical  and
economic feasibility of substituting various chemical  compounds  and
physical processes for six halogenated compounds:  trichloroethene;
tetrachloroethene (perchloroethylene); dichloromethane (methylene
chloride); 1,1,1-trichloroethane (methyl chloroform);  tetrachloromethane
(carbon tetrachloride); and 1,1,2-trichloro-l,2,2-trifluoroethane
(CFC-113).  These six were chosen for study because the Environmental
Protection Agency (EPA), as well  as other Federal regulatory agencies,
have developed,  or are in the  process of developing, regulations that
directly or indirectly impact  these solvents.   Because these regulations
result from different statutory authorities exercized  by different
agencies, there  exists the potential for conflict, overlap and/or
gaps among the regulatory actions.
     The purpose of this report is  to provide  the Environmental  Protection
Agency with preliminary information concerning the substitution  of
various other chemicals and physical processes for the six halogenated
solvents in order to assist in the  conduct of  the regulatory analysis.
This report identifies potential  substitutes for these solvents  and
presents a preliminary analysis of  relevant technical  and economic
issues.  This report should not be  considered  a complete substitutes
analysis for two reasons:  first, it evaluates neither the health
effects of the halogenated solvents nor the substitutes identified.
For example, certain aromatic, aliphatic, and  oxygenated solvents  were
identified as potential substitutes in certain situations.  These
solvents are photochemically reactive.  The potential  increase in  ozone
concentrations versus the potential decrease in halogenated solvent
concentrations was not investigated.  Second,  although the substitutes
                                    1-1

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analysis addresses the capital  and annualized costs  of substitution  to
the user, it does not address the user's ability to  pay the  costs  of
substitution.  A complete economic analysis would need to  address  this,
as well as the costs to producers of the halogenated solvents,
substitutes, and their distributors.  It should be stressed  that
although several substitutes have been identified, they may  not be
applicable in every situation.   Applicability must be determined on  a
case-by-case basis.
     In accordance with EPA Order 2200, this report  has been distributed
for external review and comment.  Of the approximately 100 copies
distributed for review, only 2 commenters responded:  E.I. du Pont
de Nemours and Company (DuPont), and the Halogenated Cleaning Solvent
Association (HCSA).  Comments made by DuPont and HCSA can  be found in
Appendices A and B of this document respectively.
     The substitutes analysis focuses on four industrial use categories:
metal cleaning, dry cleaning, paint formulation, and fabric  scouring.
These source categories were chosen following a screening  study in
which all categories that use the halogenated solvents were  investigated.
Metal cleaning, dry cleaning, paint formulation, and fabric  scouring
were chosen because the screening study showed that substitution in
these categories was feasible.  In addition, metal cleaning  and dry
cleaning use more of the halogenated solvents than any other use category.
     Although the six halogenated solvents investigated have many of
the same properties, such as good solvency, nonflammability, and high
vapor density,  they are not completely interchangeable.  Thus,  some  of
the substitutes that are mentioned may not be suitable for all  of the
solvents in certain situations.  This particularly true for CFC-113.
This solvent is approximately four times more expensive than the other
halogenated solvents, and is often used when nothing else  will  do the
job adequately.  It's low boiling point, mild solvent properties, and
low toxicity make it advantageous in the electronics industry where
extremely low levels of residues and soil are essential to the product's
end-use  and  reliability.
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1.2  METHODOLOGY
1.2.1  Description
     The solvent substitute feasibility analysis presented in  this  report
is in the form of a screening study.  First,  a comprehensive list of
possible substitutes was compiled for each industrial  use category.   These
were then screened, based on technical  performance, general  availability,
and relative cost, to identify those with the most likelihood  for use.
That group was then subjected to more detailed technical  and economic
feasibility analyses to assess the probability of use.
1 .2.2  Limitations
     The user of information in this screening study should be aware of
the limitations of the findings.  First, the scope of this effort,
precluded a complete analysis of the technical and economic feasiblity of
substitution.  By its very nature, the feasibility of substitution  is a
complex subject.  From a technical perspective, substitution for solvents
in a given use category can range from being relatively straightforward to
very complex.  For example, petroleum solvents under certain circumstances
and restrictions can serve as a good technical substitute for
perchloroethylene in dry cleaning operations.  However, in metal cleaning
operations, the number and the type of substitutes for solvents is  large
and the technical performance varies from application to application.  In
certain instances, there are no substitutes for halogenatec1 solvents.  For
example, aqueous cleaning can substitute effectively for vapor degreasing
in cleaning automotive transmissions gears; however for cleaning many
kinds of electronic assemblies only certain halogenated solvents will do
the job adequately.  Also, there are huge data gaps with respect to
technical performance of substitutes.  In metal cleaning this results
because the use category is not a single industry but a process used in
thousands of different industries.
     From an economic standpoint this report addresses only the issue of
the cost of substitution of the user.  A complete economic analysis would
also need to assess the costs incurred by other affected parties due to an
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increased level  of substitute usage.   These affected parties  would  include
the manufacturers of substitutes; solvent producers; solvent  and  substitute
distributors; and consumers.   Some of these affected parties  would
experience a decrease in demand for their products and services while
others would benefit from the shift in demand towards their sector.
Producers of halogenated solvents would experience a decline  in  sales  of
their product while producers of substitute compounds would enjoy an
increase in sales.  Consumers may be forced to finance much of the  costs
of solvent substitution in the form of higher prices for goods formerly
processed by a solvent system.
     The type of regulatory action being considered would determine the
scope of any complete economic impact analysis.  For example, if  substitution
increases because a regulation limits production of the chemical  of
concern, the economic feasibility of substitution cannot be determined
without data on the manufacturers of the substituted product, e.g.  excess
capacity, ability to finance increased production, and the price
elasticity of the demand for the substitute.  The above factors  will affect
the price of the substitute, which in turn affects the costs of the
substitute to the users.
     Definitive conclusions on substitution cannot yet be reached for all
potential users in all industries.  In this report, estimates of user's
costs were confined to increased capital and annual operating costs.
Extensive data gaps need to be filled before the probable economic effects
of a regulatory policy which would encourage substitution away from the
chemicals of concern could be predicted.   Identifying specific regulatory
alternatives is an essential element in the development of the proper
analytical methodology for filling these data gaps.
1 .3  SUMMARY OF FINDINGS
1.3.1  Metal Cleaning
     Trichloroethylene, perchloroethylene, 1,1,1-trichloroethane, methylene
chloride, and trichlorotrifluoroethane are presently used in metal  cleaning
because  their unique physical properties make them  advantageous in many
instances in comparison with other metal cleaning methods.  Their solvent
                                    1-4

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power, vapor density, vapor pressure,  boiling  range,  and  nonflammability,
in conjunction with the nonphotochemical  reactivity of some  make  them
attractive as metal cleaning solvents.  For substitutes to  be  effective,
they must be able to remove soils as safely and effectively  as halogenated
solvents and at comparable cost.
     Probable substitutes to metal cleaning with trichloroethylene,
perchloroethylene, methylene chloride, 1,1,1-trichloroethane,  and
trichlorotrifluoroethane can be broken down into four separate subcategories:
aqueous cleaning, emulsion cleaning, nonchemical cleaning,  and cleaning
with other organic solvents.
     Aqueous cleaning describes a wide range of water-based  cleaning
methods which use combinations of either acidic or alkaline  compounds
to displace soils rather than dissolving them in an organic  solvent.
Emulsion cleaning describes those cleaning techniques which  remove
soils by the use of common organic solvents such as mineral  spirits,
which are dispersed as fine droplets in an aqueous medium with the aid
of an emulsifying agent.  Nonchemical  cleaning techniques principally
rely on the use of mechanical energy as opposed to chemical  or aqueous
media to remove soil.  The nonchemical cleaning technique examined in
this analysis is abrasive blasting with materials such as aluminum
oxide, silica sand, and glass beads.  Metal cleaning with other organic
solvents describes those processes that use aromatic, aliphatic,  oxygenated,
and other halogenated solvents.
     Based on general cost comparisons, relative ability to meet production
volume requirements, and product quality considerations, aqueous cleaning
is a viable substitute cleaning method for many metal cleaning operations
currently using solvents (see Section 2.3.1).    Its principal disadvantages
are that the materials are wet after cleaning and ferrous metals rust
in aqueous environments.  However, technological innovation on the part
of aqueous cleaning equipment and cleaning compound manufacturers is
anticipated to increase both the technical and economic parity of this
substitute method with solvent metal cleaning.
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     Substitution with  other organic solvents,  such  as  mineral  spirits,
also appears to be a viable alternative to cleaning  with  the  six  halogenated
solvents in certain cases (see Section 2.3.4).   This is a particularly
valid substitute for many maintenance and repair operations using room
temperature cleaning because no new equipment would  need  to be  purchased
and installed.  The disadvantage of other organic solvents is that
most, if not all, are flammable.  One halogenated solvent, trichlorofluoro-
methane (CFC-11), has been identified as a technological  substitute  to
trichloroethylene, 1,1 ,1-trichloroethane, methylene  chloride, and
trichlorotrifluoroethane  (CFC-113) as a vapor degreasing  agent  for
solvent metal cleaning.   Its physical properties and solvent  characteristics
are compatible with use in modified existing vapor degreasing equipment.
However, CFC-11 is regulated under the Toxic Substances Control Act  as
an aerosol propel 1 ant because of its potential  to damage  the  stratospheric
            2
ozone layer.
     The method which seems to possess the smallest  degree of substitutability
for either cold cleaning  or vapor degreasing is abrasive  blasting
(Section 2.3.3).  Abrasive blasting generally is not capable  of meeting
the same product quality  standards other than for items with  no surface
finish requirements.  In  addition, it cannot be adapted readily for  use
on objects with complex shapes or internal passages.
1  .3.2  Dry Cleaning
     Dry cleaning is a  process for cleaning clothes  with  organic  solvents
instead of detergent and  water.  Perch!oroethylene and/or trichlorotri-
fluoroethane (CFC-113)  are used in coin-operated cleaners and in  certain
industrial and commercial facilities.  They are used because  of their
excellent solvent properties, gentle cleaning characteristics,  non-
flammability, and compatability with all types  of dry cleaning  equipment.
     Petroleum solvents are also used by the dry cleaning industry and
are the only commercially available substitutes (see Section  3.1).
Although they are used primarily by industrial  cleaners,  they can be
used in the commercial  sector.  They cannot be  used  by the coin-operated
sector because of flammability.  Petroleum solvents  are mixtures  of
                                   1-6

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paraffins and aromatic hydrocarbons similar to kerosene.   Petroleum
solvents are comparable to perchloroethylene and CFC-113  in  their
ability to clean soiled articles.   The equipment used to  dry clean with
petroleum solvents is similar to the equipment used to clean with
perchloroethylene and CFC-113.  However, because petroleum solvents  are
combustible, new dry cleaning equipment specifically designed for
petroleum solvents must be installed to replace equipment designed for
perchloroethylene and CFC-113.
     While petroleum solvents commonly are used in dry cleaning,  local
fire codes may prohibit large scale substitution to these solvents.   The
fire codes for combustible solvents, such as petroleum solvents,  include
special fire-resistant construction of the building, special wiring, a
sprinkler system, and a special  heating system for the building.   In many
cases, depending on the building type, location, size, and ownership, a
dry cleaner may be unable to make the structural changes  necessary to meet
the requirements of fire codes.   Also, fire codes in some areas  make
substituting petroleum solvents  for nonflammable solvents illegal.   The
constraints placed on dry cleaners by fire codes and the  associated  costs
of retrofitting facilities make  substitution for perchloroethylene and
CFC-113 dry cleaners infeasible  for many existing establishments.
1.3.3  Surface Coating
     The three major types of surface coatings are paints, lacquers, and
finishes.  These surface coatings are grouped into three  main use categories
architectural paints, product finishes, and special purpose coatings.
Surface coatings have a variety of uses including decoration, weather and
chemical protection, and safety marking.
     Surface coatings are typically composed of three components:  a
binder, a pigment system, and a solvent.  Historically, the solvents first
used in surface coating were wood chemicals.  Later, simple petroleum
derivatives (aliphatics and aromatics) began to find greater use.  Both
wood and petroleum solvents enjoyed low cost and were readily available.
In later years, other types of solvents made inroads in specialty areas.
Today, available literature and industry sources indicate that chlorinated
                                   1-7

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solvents are used primarily in special  purpose  coatings  for two  types  of
products:   aerosol  paints and traffic paints.   However,  because  of
their high cost, chlorinated solvents account  for only a small  percentage
of all solvents used in surface coating applications (see Section  4.1).
One industry source estimates that methylene chloride accounts  for only
about 0.4 percent of all solvents used annually in all surface  coatings.
Likewise, 1 ,1 ,1-trichloroethane accounts for only about 7.5 percent and
methylene chloride accounts for only 1.6 percent of all  solvents used
in traffic paints.
     Because 1,1,1-trichloroethane and methylene chloride are not
photochemically reactive, they are being marketed aggressively  as
substitutes for various aliphatic and aromatic  solvents presently  used
in surface coating operations.  Thus, the amount of 1,1,1-trichloroethane
and methylene chloride used in traffic paints  and aerosol paints may
actually increase.   Use of 1,1,1-trichloroethane and methylene  chloride
may expand to other surface coating operations  including architectural
coatings and product finishes.  This report does not examine the potential
impact of this phenomenon.  Rather, it only examines the practicality
of replacing chlorinated solvents with conventional solvents.  Potential
substitutes for chlorinated solvents are wood  and petroleum solvents.
The most common substitutes for the chlorinated solvents are acetone,
methyl ethyl ketone, toluene, and hexane.  The  use of these substitute
solvents for methylene chloride and 1,1,1-trichloroethane should not
have a significant effect on the product quality of most reformulated
aerosol paints or traffic paints.  However, one industry source estimates
that about 10  percent of aerosol paint formulations could not be reformulated
to use a solvent other than methylene chloride.
1.3.4  Fabric Scouring
     Fabric scouring is the process for cleaning textile fibers or
fabrics during their manufacture.  Fabric scouring can be performed
using either aqueous or solvent media.  In aqueous scouring, an aqueous-based
solution containing alkali reagents and anionic or nonionic surfactants
is used.  Fabric scouring may be performed in  a batch or continuous
process with the continuous process being used most often.
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     Solvent scouring currently is used primarily for the cleaning of
synthetic knit goods prior to finishing.  Solvents are effective at
removing the knitting oils applied to yarns to facilitate knitting.
Solvents are not as effective in removing the chemicals that are used
in making woven goods; therefore, solvent scouring generally is limited
to the knit fabric segment of the textile industry.
     Perchloroethylene is a solvent frequently used  in scouring.
Trichloroethylene is also used, and recently trichlorotrifluoroethane
has come into use.  Several other organic solvents,  such-as  benzene,
xylene, petroleum solvents, and 1,1-dichloroethylene, have been reported
as potential substitutes although none are presently known to be used
in fabric scouring, and information concerning their technical  and
economic feasibility as substitute solvents is not available.
1 .4  RECOMMENDATIONS FOR FUTURE STUDY
     Future study of solvent substitutes depends  on  the regulatory
impetus for solvent substitution.  Regulation of  solvents can be direct,
such as a production cap; or indirect, such as controlling indicator
substances like volatile organic compounds.  The  technical  and  economic
feasibility of substitution would likely differ depending upon  which
scenario is in place.
     If direct control strategies are studied, then  the study effort
must include solvent producers, solvent/substitute users, and substitute
producers.  The interaction of all  markets must be considered to understand
the technical  and economic dynamics of substitution.   If production of
a  specific solvent is limited artifically (in terms  of free  markets)
due to regulation, then it would be important to  understand  the effects
this reduced demand would have on the solvent manufacturer and  the
associated channels of distribution.   Likewise, the  reduced  demand for
solvents would cause an increased demand for substitutes.  For  both
solvent and substitute producers the  following need  to be addressed:
                                   1-9

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     •    Potential  price changes  for intermediate  and  final  products.
     •    Potential  impacts  on profitability of discrete  chemical
          operations.
     •    Potential  changes  in employment in producing  industry.
     •    Potential  changes  in capacity and production.
     •    Potential  changes  in sales and jobs within the  distribution
          network.
In order to evaluate the above items, detailed historical  information  is
needed on total  capacity, capacity utilization, sales,  profits,  prices
and end uses.  In addition,  both the fixed and variable  costs of production
need to be identified for each segment of the industries  being analyzed.
It is desirable to evaluate  the relationship between the  solvent and
solvent substitute producing industries.
     Indirect control  strategies might require much of  the same  study,
but because it is not likely that solvent demand would  be reduced with  an
indirect control  strategy, less emphasis could be placed  on solvent
manufacturers and more placed on technical and economic  feasiblity for
solvent/substitute users and substitute producers.   Under this scenario,
the information contained in this report becomes important in shaping
future study needs.
     Following are some recommendations for future  study  for three of
the four user categories studied in this report.
1.4.1  Metal Cleaning
     Additional study in this area needs to be undertaken before definitive
conclusions can be drawn about the technical and economic feasibility  of
substitutes for solvents.  For example, this preliminary  analysis
attempted to measure economic feasibility in terms  of the capital and
annualized operating costs of substitutes.  However, the  only comparative
data found were dated.  The  scope of past studies has been to compare
cost and technical compatibility on a one-to-one replacement basis
(e.g., aqueous washing systems versus open top vapor degreasers).  With
                                    1-10

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changing technology, utility costs, and solvent prices, it is not known
if the specific examples cited in this report can be extrapolated to
other industrial categories.  Thus, a specific methodology, perhaps in
the form of an economic model, should be devised to perform economic
analyses using current price and cost parameters.  Additionally, more
work needs to be conducted to determine current usage of solvents
versus substitutes.
1.4.2  Dry Cleaning
     Although substitution of petroleum solvents for perchloroethylene and
CFC-113 is possible on a technical  and cost basis, the economics of
retrofitting to meet fire codes was not investigated.  Prior to this,
fire codes need to be reviewed to determine how many areas would allow
petroleum solvent substitution.  Likewise, commercial and industrial
cleaners should be surveyed to determine how many could substitute at
their present location.
1.4.3  Surface Coating
     Because certain chlorinated solvents are not photochemically reactive,
solvent producers are making a concerted effort to increase sales of
chlorinated solvents to paint formulators.  Little data are available
concerning the potential  increase in the use of nonphotochemically reactive
solvents in the surface coatings industry.  Study is also needed
on the health and environmental impacts such substitution may have.
1.4.4  Fabric Scouring
     A preliminary model  plant analysis was used to estimate capital  and
annualized operating costs of substituting aqueous scouring for solvent
scouring.  To complete a more detailed analysis, the parameters of the
model  plants (used in developing cost estimates) need to be examined  for
relevance in today's market.  Also, it would be useful  to know the number
of mills using aqueous vs. solvent  systems, a better estimate of product
quality differences between the two, and the extent to which drying  vs.
nondrying procedures are implemented when aqueous systems are used.
                                   1-11

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1.5  REFERENCES

 1.  U.S. Environmental  Protection Agency.  Materials Balance Summaries
     for Trichloroethylene,  Perchloroethylene,  1,1,1-Trichloroethane,
     Methylene Chloride, and Trichlorotrifluoroethane.  Office of
     Toxics Integration.  Washington,  DC.  August  1981.

 2.  U.S. Environmental  Protection Agency.  Prohibition of Manufacturing,
     Processing,  and  Distribution in Commerce of Fully Halogenated
     Chlorofluoroalkanes for Aerosol Propellant Uses.  40 CFR 712, 762.
     Office of Toxic  Substances.   March  17, 1978.
                                   1-12

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                             2.0  METAL CLEANING

2.1   GENERAL DESCRIPTION OF USE
2.1.1  Industry Characterization
     Metal cleaning does not constitute a distinct industrial  category but
rather is an integral  processing operation used in the manufacturing,  main-
tenance, and repair of virtually all  metal based commodities.   Trichloro-
ethylene, perchloroethylene, methylene chloride, 1,1,1-trichloroethane,  and
trichlorotrifluoroethane are widely employed in manufacturing  applications as
cleaning agents to facilitate the removal of drawing  compounds, cutting
fluids, coolants and lubricants.  Typically, such metal working compounds
possess a grease or oil  base which is removed by the  action of one or  more of
the solvents listed above.   These solvents are also used in maintenance  and
repair applications to remove similar contaminants prior to inspection,
machining, rebuilding, and  assembly.
     Trichloroethylene,  perchloroethylene, methylene  chloride,
1,1,1-trichloroethane, and  trichlorotrifluoroethane are widely used in metal
cleaning because they exhibit excellent solvency for  most industrial
contaminants, have rapid evaporation  rates, are chemically compatible  with most
metals, and are nonflammable.  Carbon tetrachloride,  although  once a  popularly
used metal cleaning solvent, is no longer used for that purpose because  of
its relatively high toxicity.
     Metal cleaning is used in a large number of manufacturing sectors and
several service sectors  (maintenance  and repair activities) within the economy.
Manufacturing industries which use metal cleaning are included within  the
following two-digit Standard Industrial Classification (SIC) code sectors:
25 (Metal Furniture),  33 (Primary Metals), 34 (Fabricated Products),  35
 (Nonelectric Machinery), 36 (Electric Equipment), 37  (Transportation Equipment),
38 (Instruments and Clocks), and 39 (Miscellaneous Industry).   Service sectors
which do metal cleaning include:  401 (Railroads-maintenance), 458 (Air Transport-
maintenance), and 758 (Auto Repair).
                                      2-1

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     As noted, the industries which use metal  cleaning vary substantially.
Metal cleaning occurs in large manufacturing operations employing  thousands
of people and in small  repair shops employing few people.   There  is  no
direct connection between the size of an operation and the amount  of
metal cleaning done in any particular industry.   In addition it should  be
noted that not all plants within the SIC codes listed above do solvent
metal cleaning.  Estimates range from a low of 39 percent  for SIC  39
(Miscellaneous Industry), to a high of 65 percent for SIC  38 (Instruments
and Clocks).
     Solvent cleaning may be divided into two categories based on  the
temperature of the solvent employed:  cold cleaning and vapor degreasing.
In cold cleaning operations, both halogenated and nonhalogenated  solvents
are used depending upon the nature of the particular application.   Vapor
degreasing operations, however, require the use of halogenated solvents
(i.e. trichloroethylene, perchloroethylene, methylene chloride, 1,1,1-
trichloroethane, and trichlorotrifluoroethane) due to their unique
physical properties of possessing nonflammable vapors that are heavier
than air.  Table 2-1 lists the distribution of these solvents in  cold
cleaning and vapor degreasing based on information provided by the Office
of Toxics  Integration, while Table 2-2 lists the estimated number of cold
cleaners,  open top vapor degreasers and conveyorized degreasers by SIC
code in 1980.
     Cleaning with halogenated and nonhalogenated solvents is commonplace
in maintenance industries such as automotive, railroad, bus, aircraft,
truck and  electric tool repair facilities.  Many of these businesses use
trichloroethylene, perchloroethylene, methylene chloride,  1,1,1-trichloroethane,
and  trichlorotrifluoroethane at least occasionally, if not on a regular
basis.
2.1.2   Process Description
     Cold  cleaning operations use solvent at or near ambient temperature.
The  solvent chosen may be heated but always remains well below its boiling
point.  This class of solvent cleaning ranges in sophistication from
simple  handwiping with a solvent-soaked cloth or sponge to the use of
extensively engineered machinery which clean parts by spraying, flushing,
                                    2-2

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TABLE 2-1.   SOLVENT CONSUMPTION IN COLD CLEANING AND VAPOR
            DECREASING, MG/YR (1980)1

Trichloroethylene
Perchloroethylene
1 ,1 ,1-Trichloroethane
Methyl ene Chloride
Tr i chl orotri f 1 uoroethane
Cold
cleaning
25,000
15,600
106,600
40,100
9,100
Vapor
degreasing
85,000
38,300
80,400
12,200
38,900
Total
110,000
53,900
187,000
52,300
48,000
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TABLE  2-2.   ESTIMATED  NUMBER OF ORGANIC  SOLVENT CLEANERS BY SIC CODE  (1980)'
Standard
industrial
classification
(SIC)
25
254
259
33
332
335
336
339
34
342
343
344
345
346
347
348
349
35
351
352
353
354
355
356
357
358
359
36
361
362
364
366
367
369

37
371
372
376
379
38
381
382
39
401
458
753
Industry
Metal Furniture
Partitions and Fixtures
Miscellaneous Furniture and Fixtures
Primary Metals
Iron and Steel Foundries
Nonferrous Rolling and Drawing
Nonferrous Foundries
Miscellaneous Primary Metal Products
Fabricated Products
Cutlery, Hand Tools and Hardware
Plumbing, and Heating (Nonelectric)
Fabricated Structural Metal Products
Screw Machine Products, Bolts, etc.
Metal Forgings and Stampings
Metal Services
Ordnance and Accessories
Miscellaneous Fabricated Metal Products
Nonelectric Machinery
Engines and Turbines
Farm and Garden Machinery
Construction and Related Machinery
Metalworking Machinery
Special Industry Machinery
General Industry Machinery
Office and Computing Machinery
Refrigeration and Service Machinery
Miscellaneous Machinery (Nonelectric)
Electric Equipment
Electric Distributing Equipment
Electrical Industrial Apparatus
Electric Lighting and Wiring Equipment
Communication Equipment
Electronic Components and Accessories
Miscellaneous Electrical Equipment
and Supplies
Transportation Equipment
Motor Vehicles and Equipment
Aircraft and Parts
Guided Missiles, Space Vehicles, Parts
Miscellaneous Transportation Equipment
Instruments and Clocks
Engineering and Scientific Instruments
Measuring and Controlling Devices
Miscellaneous Industry
Rail roads -Maintenance
Air Transport-Maintenance
Auto Repair
No. of
plants

3,710
2,095

1,932
1,596
3,714
1,265

4,238
2,277
19,172
3,263
5,427
6,611
467
8,670

576
3,428
6,151
16,729
7,282
8,171
2,756
3,630
28,807

1,646
3,001
3,616
4,647
7,453
2,815


6,533
2,120
128
2,684

1,550
4,501
31,723
1,196
4,512
115,591
No. of
cold
cleaners

7,165
3,800

4,759
2,226
4.020
9,626

13,716
2,759
32,604
3,861
7,612
21,591
148
18,058

916
10,322
13,383
48,446
11,820
38,249
7,371
7,128
98,290

4,652
4,748
11,907
13,496
13,577
6,357


13,041
14,070
841
4,606

7,423
21,704
19,997
1,267
48,832
518,633
No. of
open top
vapor
degreasers

467
145

374
314
119
1,420

1,518
233
1,145
130
303
1,447
6
1,112

44
435
622
825
53
2,66*
404
226
1,532

1,174
366
3,066
3,452
2,072
103


857
3,733
239
0

766
4,450
880
84
5,020
0
No. of
conveyorized
degreasers

133
41

79
68
24
303

316
48
237
27
63
301
1
230

7
80
113
151
10
489
74
40
280

133
40
345
387
232
12


104
452
29
0

38
223
90
0
0
0
                                TOTAL
335,783
1,073,079
41,800
5,200
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or ultrasonically agitating the solvent.   The type of cold cleaning
technique and solvent to be used in a given application depends  upon  a
number of variables such as:   size and shape of parts to be cleaned,  type
of contaminant to be removed, the degree  of cleanliness required,  and  •
solvent cost.
     While there exist a number of different vapor degreasing  designs of
various sizes, all  have three fundamental  structural  features  in common:   a
tank to contain the solvent and solvent vapors, a heating system with which
to boil the solvent, and a cooling system used to control the  diffusion of
solvent vapors from the tank.  The solvent is raised  to its boiling  point by
the heating system to generate the solvent vapors.  The resultant solvent
vapors act to displace the air within the degreaser which ensures  that  the
maximum amount of solvent will be available for cleaning.  The upper  level of
the solvent vapor is controlled by the cooling system which contains  condenser
coils located part of the way up the sidewalls of the degreaser.   The
condenser coils are designed to remove enough heat from the solvent  vapor
layer so that condensation of solvent onto the cooling coils minimizes  the
diffusional loss of solvent vapors away from the degreaser. Thus, a  heat
balance is maintained within the vapor degreaser which simultaneously allows
large quantities of solvent vapors to be  generated as well  as  contained.
This balance enables parts to be effectively cleaned  and the solvent  continuously
distilled.
     There are two basic types of vapor degreasers:  open top  vapor  degreasers
and conveyorized degreasers.   Open top vapor degreasers are batch  operated.
Parts to be cleaned are generally racked  together in  a vapor-permeable  basket
which is then introduced through the top  of the unit  into the  vapor  zone
where condensation can then take place.  In addition  to condensing coils,
most open top vapor degreasers are also equipped with a water  jacket  which
provides additional cooling to prevent hot solvent vapors from convecting up
the degreaser sidewalls and out the top of the degreaser.
     The principles by which a conveyorized degreaser operates are identical
to those of an open top vapor degreaser,  with the exception that conveyorized
units use an automated conveyor system.  Parts are continuously  or multiply
loaded and then conducted through the degreaser via the conveyor system.
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In contrast to open top units, conveyorized degreasers almost always
contain the solvent and solvent vapors in an enclosed or hooded tank  to
control solvent losses due to diffusion and convective air motion around
the degreaser.  Due to the inherently greater load processing capability
of conveyorized degreasers relative to similarly sized open top units,
they are most commonly found in plants with a large quantity of parts to
be cleaned.
     It has been estimated that approximately 174,000 cold cleaners,
41,800 open top vapor degreasers, and 5,200 conveyorized degreasers  using
either trichloroethylene, perchloroethylene, 1,1,1-trichloroethane,
methylene chloride, or trichlorotrifluoroethane were in operation in  1980.
2.2  SELECTION OF CLEANING METHODS
     The industrial cleaning of metallic parts  and products is an extremely
broad and inherently diversified field.  This is due to the extensive
number of different manufacturing, maintenance, and repair operations that
necessitate the use of clean components and assemblies in virtually  every
aspect of processing and production.  In general,  an extensive set of
independent variables and technical considerations must be evaluated  prior
to the selection of any method to fulfill a given  cleaning requirement.
Major factors which influence the selection of  any cleaning method
include:
     t    Physical and chemical properties of the  contaminant to be
          removed,
     •    Physical and chemical properties of the  substrate on which  a
          contaminant is deposited,
     t    The amount of contaminant to be removed,
     •    The degree of .cleaning efficiency required,
     •    The size, shape, and complexity of parts or object to be
          cleaned,
     •    The volume or number of parts or objects to be cleaned per  unit
          of time, and
     •    The substrate preparation required.
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     Additional parameters important in the selection of a cleaning
process include:  factory floor space available, water availability,
wastewater treatment availability, regulatory requirements, ventilation
requirements, energy consumption, and waste disposal.
     Careful consideration of the above criteria often will not uniquely
specify any one particular cleaning method, but usually indicates several
methods which must then undergo further evaluation based on additional
factors such as the cost, safety, and environmental  impacts associated
with the use of each candidate method.  The relative importance assigned
each of these criteria will  vary among potential users with similar
cleaning requirements depending on their production schedules, location,
or previous experience with a candidate cleaning method.  Even after such
a selective screening process has been completed, final bench scale
testing is required frequently to quantify the effectiveness of a candidate
method under simulated operating conditions.
     The cleaning methods most often used by industry principally rely  on
                                                                          4
one or more of the following mechanisms to facilitate contaminant removal:
     •    Solvent Action — Removal of contaminants through the use of
          various halogenated and nonhalogenated solvents.
     •    Detergent Action -- Displacement of contaminants through the  use
          of various surface active agents (surfactants).  These compounds
          exhibit a greater chemical attraction to the substrate than for
          the contaminants adhering to the substrate.  This difference  in
          affinities preferentially removes the contaminant through
          displacement by the surfactant.
     •    Chemical Reaction -- Use of various chemical compounds to react
          with contaminants in such a way as to form soluble inert reaction
          products which are then removed from the substrate.
     •    Mechanical Action — Use of mechanical energy applied through
          techniques such as brushing, spraying, abrasion, impaction, or
          wiping to displace the contaminant from the substrate.
     In order to consider the applicability of one of the preceding
cleaning mechanisms to a given cleaning requirement, it is important that
the type of contaminant to be removed be characterized accurately.
Commonly encountered industrial contaminants are classifiable into six
principal types: '
                                    2-7

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     •    Pigmented Drawing Compounds -- These materials commonly are used
          in press and punch working procedures.   They normally consist of
          oil-based compounds to which a pigment  such as lime,  talc,  chalk,
          sulfur, lithipone, or graphite is added to help overcome the
          frictional resistance of the machining  operation, and to increase
          the formability of a material.  Pigmented drawing compounds
          generally are used in press fabrication of parts with complex
          shapes.

     •    Unpigmented Drawing Compounds -- These  materials usually are
          formulated with mineral oils and greases, vegetable or animal
          oils, and/or fats.  These compounds are used in the press forming
          of simple to moderately complex shaped  parts.

     •    Polishing and Buffing Compounds -- The  materials are  composed of
          varying combinations of greases, metallic soaps, abrasives, and
          waxes.  These compounds may also contain very fine metal
          particles following a polishing or buffing operation.

     •    Cutting and Grinding Fluids -- These compounds consist of a
          variety of plain and sulfurized mineral and fatty oils,
          chlorinated mineral oils, soaps, salts, and saturated fatty
          alcohols.

     •    Oxidation and Scale -- These materials  consist of combinations of
          rust, heavy metal salts, and assorted metallic oxides.  Unlike
          the preceding compounds, these substances are corrosion products
          rather than additives used to increase  the formability of the
          material.

     •    Miscellaneous Surface Contaminants -- This class of contaminants
          includes a broad range of commonly encountered industrial soils
          such as metal chips, carbon deposits, fluxes, quenching oils, and
          various salt deposits.


     Halogenated solvents are used to remove greases and oils such as the

unpigmented drawing compounds.  They are somewhat limited in effectiveness

in the removal of pigmented drawing compounds, polishing and buffing

compounds, or cutting and grinding compounds.   Solvent degreasing with

spraying or ultrasonic agitation can remove these contaminants  when the

media carrying the abrasives are solvent soluble.  When the media are

water soluble or soluble in alkaline solutions, aqueous cleaning can be

effective.  Pigmented drawing compounds, polishing and buffing  compounds,

and cutting and grinding fluids are more difficult to remove from a
                                   2-8

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metallic substrate due to their chemical  inertness and strong adhesive
characteristics.  Buffing compounds can be extremely difficult to  remove
when they are "heat set" by the frictional heat generated by abrasion.
     Substitutes to degreasing processes  using halogenated solvents  fall
under four broad categories:   aqueous cleaning, emulsion cleaning,  nonchemical
cleaning, and cleaning with other organic solvents.   It is these  four
methods which are analyzed for potential  technical and economic
substitutability.
2.3  TECHNICAL ANALYSIS OF SUBSTITUTES
     This section analyzes the technical  feasiblity of substituting  each
of the preceding alternative cleaning methods for degreasing with  halo-
genated solvents.  The section outlines how each substitute process
functions and analyzes whether each of the substitutes identified  is a
complete or partial substitute in various applications, the adequacy of
each substitute's performance, the quality of the end product, availability
of equipment, materials, and technical skills required to utilize  each
substitute, and the time required to implement the substitution.
2.3.1  Aqueous Cleaning
2.3.1.1  Process Description
     Aqueous cleaning describes a wide range of water-based cleaning
methods used to remove contaminants from  assorted materials.  Simple hot
water, in combination with mechanical, electrical, or ultrasonic  energy,
is considered to have adequate cleaning properties in many applications.
This effectiveness primarily derives from temperature-induced viscosity
changes in contaminants such as greases and oils, which along with  subse-
quent agitation helps to remove a portion of the soil.  This cleaning
action is usually supplemented with chemical agents  which act to  displace
soils rather than dissolving them in an organic solvent.
     Aqueous cleaning techniques may be divided into five categories:
     •    Immersion or Soak Cleaning -- Work is placed into the cleaning
          solution, allowed to soak, removed, rinsed, and then dried.
          Removal of soils is dependent on surfactant action and  heat.
                                   2-9

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     t    Spray Cleaning -- This  method  adds  mechanical  energy  from  a
          pressurized spray to improve  cleaning  efficiency.   This  technique
          is often adapted for use with  a  conveyorized  load  handling system,
          allowing large volumes  of work to  be  processed.
     •    Ultrasonic Cleaning --  This  process uses  high  frequency  sound  to
          induce a rapid formation and  collapse  of  gas  bubbles  (cavitation)
          in the cleaning solution.  The violent collapse  of the bubbles
          produces a strong cleaning action  which supplements the  cleaning
          effectiveness of the solution.
     t    Electrocleaning — Metal parts to  be  cleaned  are immersed  in a
          cleaning solution through which  an  electric current is conducted.
          The parts act as the anode or  cathode  of  the  circuit.  The water
          in the cleaning solution is  electrolytically  decomposed  on the
          work, releasing large volumes  of tiny  hydrogen and oxygen
          bubbles.  The evolved bubbles  impart  a powerful  agitation  aiding
          in lifting and removing contaminants.
     •    Steam Cleaning -- A pressurized  steam  spray is mixed  with  small
          amounts of alkaline cleaning  solution  to  remove  contaminants.
          The high pressure and temperature  of  the  mixture reduces the
          viscosity of the contaminants  and  displaces them through the
          impingement of the spray.
     Aqueous cleaning systems are classified  into two general types  based
on the pH of the cleaning solution employed:  alkaline  cleaners and  acid
cleaners.  Alkaline cleaning compounds  consist  of various  combinations of
builders (alkaline salts) and surfactants.   Alkaline cleaning compounds
remove contaminants through one or more  of the  following process:
                                                                           g
emulsification, dispersion, wetting action,  aggregation, and saponification.
Builders form the largest percentage ingredient  of  an alkaline  cleaner.
Frequently used builders are derived from  the sodium salts of the  carbonates,
                                      q
phosphates, silicates, and hydroxides.    Detergents and  soaps are  the two
types of surfactants used in alkaline  cleaning  compounds.   Surfactants
belonging to the detergent class  are the most widely used  due to their
superior ability to soften water, disperse soil, and rinse freely  away from
the substrate being cleaned.  Commonly  used  surfactants  include anionic,
onic, nonionic, and amphoteric detergents.
     Acid cleaners are aqueous solutions consisting of  acids or acid salts,
ting agents or detergents, and occasionally  organic solvents which are
used to remove oil, dirt, or oxides from metal  surfaces.  Acid  cleaning
compounds may be based on organic acids  such  as  acetic,  oxalic, or cresylic
acid, or inorganic acids such as  sulfuric,  nitric,  or hydrochloric acid.
                                   2-10

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     Cleaning techniques used with acid cleaners include wiping,  spraying,
immersion, and electrolytic and ultrasonic cleaning.  Agitation of some type
is normally used in immersion applications, with spraying and ultrasonics
techniques used for parts or objects with complex shapes.
2.3.1.2  Method of Substitution
     The design and operating principles of vapor degreasing and  aqueous
cleaning equipment are too divergent to permit any large scale engineering
effort to modify vapor degreasers into aqueous cleaning machinery.
Solvent cleaning processes concentrate soil and contaminants for  appropriate
disposal, while aqueous processes disperse contaminants.  Therefore,  the
substitution of aqueous cleaners (alkaline or acid)  requires that new
cleaning systems be procured and installed to replace existing vapor
degreasers.  Furthermore, any ancillary equipment associated with the use
of a vapor degreasing system, such as solvent recovery stills, carbon
adsorption columns, or solvent storage tanks, would  also be of no
practical use in an aqueous cleaning system.   Since  the majority  of vapor
degreasers have been integrated into manufacturing,  maintenance,  or repair
operations, substitution of an aqueous cleaning unit could also necessitate
the reevaluation of any existing load handling system's ability to  deliver
parts for processing to the replacement unit.  Depending on plant
processing operations, modifications in hoists, conveyorized load handling
systems, or equipment relocations could be required.  Cleaning operations
substituting an aqueous system for a vapor degreaser may also require
changes in utilities services such as the need for additional  wiring  or
plumbing alterations to accommodate the substitute system.   Since energy
requirements are greater than that required for solvent cleaning  systems,
additional  steam generating capacity may be needed if not available already.
In addition, space requirements for alkaline  cleaning systems may be
greater.
     The amount of time required to implement the substitution of an
aqueous cleaning system for a vapor degresser will vary depending on
whether the aqueous cleaning equipment is in  stock or whether custom
engineering of a replacement system is required.   The normal  period of
time between ordering and receipt of a stock  aqueous cleaning system  is 4
to 6 weeks.  During times of peak ordering or exceptionally heavy demand,
                                   2-11

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delivery times for stock cleaning systems can be extended to 12 weeks.
Should the particular cleaning requirement necessitate the development  of
a custom engineered cleaning system of nominal  complexity, the time
needed for design work and manufacturing averages approximately 8 weeks
prior to shipment.  Cleaning systems of intermediate complexity on average
take 16 weeks to develop while systems requiring extreme complexity and
parts handling sophistication normally take about 16 to 20 weeks to
custom design and produce.    Manufacturers of aqueous cleaning equipment
also generally assist in the installation of their cleaning equipment by
providing on-site advice on system placement, utilities connections,  and
ways in which the system can best be integrated into existing manufacturing,
maintenance, or repair operations within the plant.
     Substitution of aqueous cleaners for cold halogenated solvent cleaning
will not, in all cases, necessitate the total replacement of all solvent
cleaning equipment.  This is because some manufacturers design the ability
to use a variety of different cleaning agents into their equipment in order
                            11 12
to increase its versatility.  '     In such a case, substitution would only
require a change of cleaning medium as opposed to any extensive modification
of plant equipment or processes.   For plants using cold cleaning systems
that are not adaptable to the use of aqueous cleaning agents, replacement
of existing equipment would be required along with the possibility of some
type of plant modifications such  as equipment relocation or changes in  the
manufacturing sequence may be needed to accomnodate the substitute system.
The degree of such modifications, however, is not likely to exceed that
involved in substitution away from a vapor degreasing system, and in  most
cases will be less since many cold solvent cleaning operations are generally
simpler in design due to intermittent cleaning demands, lower work volumes,
or the need to satisfy less stringent cleaning requirements.
     Based on contact with a manufacturer of aqueous cleaning equipment, the
time required for a user of a cold cleaning system using halogenated
solvents to retrofit with an aqueous cleaning system will  probably not
exceed 12 weeks.    Most users of cold cleaning equipment would experience
a substantially shorter transition time since the majority of industrial
                                   2-12

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cold cleaning operations are manually batch-loaded; therefore,  no capital
expenditures or additional downtime would be incurred to modify or replace
existing load handling equipment.
2.3.1.3  Degree of Substitution
     Historically, the use of aqueous cleaning by industry has  been
commonplace.  The general availability of water, its low cost,  and familiarity
combine to make it a widely used cleaning medium.  Table 2-3 shows the
relative extent to which alkaline washing systems and solvent-based systems
were used by nine two-digit SICs in 1976.    These industries comprise the
majority of industries engaged in metal cleaning operations.  When the
percent of plants using alkaline washing exclusively are taken  together
with those that use both alkaline and solvent systems jointly,  it is apparent
that alkaline washing systems are one of the most popular methods chosen
for metal cleaning.
     Cleaning systems have been designed for use with alkaline  and acidic
compounds that produce cleaning results comparable or superior  to those
systems which use halogenated solvents.  '  '    One study designed to
evaluate the comparative effectiveness of aqueous and solvent methods for
cleaning various metals was conducted by Rockwell International at the
Federal government's Rocky Flats nuclear weapons facility in Golden,
Colorado.    During the study, metals coated with common industrial  soils
were cleaned by ultrasonic vapor degreasing in trichloroethylene and
1,1,1-trichloroethane as well as being cleaned ultrasonically in an
alkaline detergent solution.  Ultrasonic vapor degreasing had been
extensively used at Rocky Flats prior to initiation of the study.  The
metals investigated included stainless steel, beryllium, uranium-niobium
alloy, and unalloyed uranium.  Following cleaning in each medium, samples
from that run were analyzed for the types and amounts of various residues
left on the surface of each metal.  Methods used in the residue analysis
included scanning electron microscopy, nondispersive x-ray and  x-ray
diffraction techniques, infrared emission spectroscopy, and mass spectroscopy.
Numerous runs were conducted with each metal and cleaning medium so that
                                   •2-13

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                TABLE 2-3.  USE OF SOLVENT AND ALKALINE CLEANING SYSTEMS BY SIC CODE, 1976
                                                                                          13
ro
i





23
33
34
35
36
37
38
39


Standard
industrial
classification
Metal Furniture
Primary Metals
Fabricated Products
Nonelectrical Machinery
Electric Equipment
Transportation Equipment
Instruments & Clocks
Miscellaneous Industry

Percentage
of plants
using solvent
systems9
29
21
23
33
34
22
42
31

Percentage
of plants
using alkal ine
systems
25
18
21
14
14
20
6
22
Percentage
of plants
using solvent
and alkaline
systems
17
19
19
19
21
28
23
8
Percentage
of plants
using no
metal cleaning
system
29
42
37
34
31
30
29
39
     'Halogenated  and  nonhalogenated solvents are included in this classification.

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the respective findings could be compared between separate metals and
cleaning techniques as well as to a set of uncleaned controls.   Significant
results of the study include:
     •    The aqueous cleaning method cleaned all four sample metals as
          well as or better than ultrasonic vapor degreasing with
          trichloroethylene or 1,1,1-trichloroethane.
     •    No evidence of any significant amount of adsorbed residual water
          could be detected for any of the metals exposed to the aqueous
          cleaning environment.
     •    Corrosion tests showed the use of an alkaline cleaning agent to
          be chemically compatible  with both the ferrous and nonferrous
          metals tested.
     •    Aqueous cleaning can remove potentially damaging chloride
          residues in industrial soils that cannot be  removed by ultrasonic
          vapor degreasing methods.

     In addition to the preceding results, the stainless steel  parts were
welded and brazed by various processes to determine the effect  of each
cleaning method on weld integrity.   Subsequent analyses by ultrasonic and
radiographic techniques for porosity, microcracks, and inclusions showed  a
slightly lower rejection rate for the preweld aqueous  cleaned joints than
for the preweld solvent cleaned joints.  Based on study findings, the use
of ultrasonic vapor degreasing at the Rocky Flats facility was  replaced
with an ultrasonic aqueous cleaning system.
     A similar study undertaken by  General Electric Company in  Waynesboro,
Virginia has also shown that aqueous systems are capable of achieving
extremely exacting levels of cleanliness.  Results of  the study have
shown that under identical operating conditions and workloads,  aqueous
cleaning of printed circuit boards  can be done up to six times  more
                                               18
effectively than similar solvent-based systems.    However, it  should be
noted that the case of G.E., Waynesboro is an individual situation, and
                                          19
should not be considered general practice.
     An example where aqueous cleaning could not be used as a substitute
is at the Boeing Military Airplane  Company in Wichita, Kansas.   Boeing
produces printed wiring assemblies  associated with a major avionics system
contract.  In the summer of 1980, humidity testing showed the assemblies
                                   2-15

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to be defective, and the aqueous/solvent cleaning system was  replaced  with
an aqueous system.  Further testing showed  these assemblies were  also
defective.  Initial  research showed that contaminants were found  to  be
present after either cleaning process.   The contaminants were of  two
forms, trace amounts of ionic metals (Sn and Pb), and a thin  organic
overcoat.  Further research by Boeing,  with assistance from DuPont,  found
                                                        ®
the only way to remove the contaminants was to use Freon  TMC (50 percent
                                                                     (R)
trichlorotrifluoroethane and 50 percent methylene chloride) and Freon   IMS
(trichlorotrifluoroethane in a constant boiling blend with 5.7 percent
methanol), followed by an isopropanol  spray rinse.  Aqueous cleaning alone
                                                     20
was inadequate in cleaning printed wiring assemblies.
     Although the use of water-based cleaning systems is widespread
throughout industry, the use of halogenated solvents has continued for
several reasons.  The traditionally low cost of halogenated solvents due
to comparatively inexpensive petroleum feedstocks and energy  resources
during the last several decades made the large scale use of these solvents
widely affordable.  The development of self-contained equipment specifically
designed to clean sizable volumes of work with solvents also  assisted  in
their growth and application.  The development of chemical stabilizer
systems that could be added to a solvent to prevent hydrolysis and inhibit
the formation of oxidation products enabled halogenated solvents  to  be
used much more effectively in the vapor degreasing process.  The  high
degree of chemical compatibility of most halogenated solvents with a wide
range of common engineering metals, plastics, glasses, and elastomers
allowed for the cleaning of workloads consisting of mixed material composition
which helped to eliminate the need to segregate parts based on susceptibility
to chemical attack.  Finally, the historical absence of any significant
Federal, State, and local regulatory pressures with respect to workplace
exposure or the environmental impacts of solvent usage also enabled  the
use of solvents in metal cleaning to expand and diversify.  Solvent
cleaning, aqueous cleaning, and other cleaning processes were chosen
solely on their engineering merit.
     Changes in the preceding factors, however, are forcing industry to
reevaluate its use of solvent-based cleaning in favor of the  increasing
                                           15 21
usage of nonsolvent-based cleaning methods.   '    Escalating  prices  for
                                   2-16

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solvents and energy along with the development of listings,  regulations
and guidelines which have been proposed or adopted in many cases  concerning
the use and disposal of solvents, have served to increase the use of
alkaline washing systems relative to that of solvents.  In addition,
continuing research and development on the part of aqueous cleaning
equipment manufacturers has advanced the state of the art of aqueous
cleaning to the point of close technical and economic parity with solvent
                             1621
systems in most applications.  '     The essentially equivalent ability of
aqueous and solvent-based systems to service a diverse range of industrial
cleaning requirements is also apparent in that the manufacturers  of
either type of system view the market for their equipment as being identical,
i e  both sectors regard themselves and their products as being mutually
     „...   14,15,21,22,23
competitive.
     One industry known to be phasing out solvent metal  cleaning  in favor
of aqueous cleaning is the automotive manufacturing industry.  Concern
over worker exposure to potentially hazardous solvents along with the
desire to minimize spent solvent disposal costs have caused major automotive
manufacturers, such as General Motors to become large scale users of
aqueous cleaning processes.   '    This phase out of solvent metal cleaning
has affected both cold cleaning and vapor degreasing operations.   Aqueous
cleaning systems are currently used by the automotive industry for virtually
all manufacturing operations  involving the processing of parts ranging
from engine components to automobile bodies.
     While the extent to which aqueous systems can be regarded as a
realistic alternative to solvent systems appears to be significant for
many degreasing tasks, there  are areas where complete substitution may be
infeasible and halogenated solvents must be used.  All such restrictions
on the  use of aqueous systems cannot be specified due to the case specific
requirements of each individual manufacturing and degreasing operation.
Aqueous  systems are likely to leave residual water of parts cleaned,
particularly  in recesses.  The retained moisture can  induce corrosion.
When aqueous  cleaning solutions must have strong alkalinity  (pH >10) to
achieve  effective  cleaning,  chemical  attack  on  aluminum  and  other  reactive
                                   2-17

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metals can be expected.   Specific areas not suitable to aqueous  cleaning
are known to include the maintenance cleaning of complex electromechanical
devices such as generators or motors.  Use of aqueous cleaning  is  limited
in these cases since electrically conductive residues left on or inside
such equipment may adversely affect its performance.  Another area with
poor substitution potential  is the cleaning of parts that require  a low
                                                 26
moisture content such as refrigeration equipment.    In some instances,
the construction and geometry of parts can prohibit the use of  aqueous
cleaning techniques.  Small, delicate parts may not be cleaned  adequately
if they possess intricate shapes, since the spray,  flushing, or  agitation
affects of aqueous washing equipment may not reach  portions of  the part's
surfaces that are recessed or otherwise protected from cleaning.   Use of
aqueous cleaning systems also may be limited, in those areas of  the
country where water is not available on a consistent basis.
2.3.1.4  Resource Availability
     Major manufacturers of aqueous cleaning equipment and cleaning
compounds were contacted to determine the ability of each sector to meet
current and future demand for its products.  In all  cases, both  sectors
viewed their respective  markets as steadily expanding due to a  combination
of factors precipitating a decrease in the use of solvents for metal
cleaning.  '  '    Estimates place the growth of the market for  aqueous
cleaning systems at approximately 10 percent annually.  According  to
leading manufacturers, sufficient production capacity exists within the
industry to service at least a doubling of demand without the need to
                                                                  28 29 30
invest in additional capital equipment, plant space, or personnel.  0»">JU
2.3.2  Emulsion Cleaning
2.3.2.1  Process Description
     Emulsion cleaning is a synthesis of organic solvent cleaning  and
aqueous cleaning.  Emulsion cleaners remove contaminants through  the
action of an organic solvent which has been dispersed or suspended as
fine droplets in an aqueous medium with the aid of  emulsifying and coupling
agents.  The emulsifying agent disperses the solvent into the water while
                                   2-18

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the coupling agent provides a mechanism for controlling the size of the
                31
solvent droplet.    The emulsifying and coupling agents enable large
amounts of solvent surface area to be created in an emulsion cleaner due
to the extremely small droplet size.  The availability of large amounts
of solvent surface area in an emulsion cleaner allow cleaning results to
be attained that are comparable to straight solvent cleaning while using
             32
less solvent.    The organic solvent component of an emulsion cleaner
generally consists of mineral spirits or similar petroleum fractions,
sometimes blended with chlorinated aromatic or naphthenic solvents to
improve the overall solvency of the formulation.
     The most common application methods used with emulsion cleaners are
immersion and spray cleaning.  In the first method, parts are allowed to
soak in a tank containing a ratio of one part emulsion concentrate to
20 parts water.  Temperatures used in this type of immersion cleaning
range from ambient up to about 10°C below the flash point of the solvent
                             32
used in the emulsion cleaner.    In the second method, cleaning is enhanced
by the mechanical  energy of the spray.  Because the energy of an impinging
solvent droplet is directly proportional  to its mass, coarser solvent
emulsions tend to increase the effectiveness of spray techniques.   Typical
solvent concentrations used in emulsion washing equipment vary from two
to five percent by volume.  Depending on the specific formulation  of the
emulsion cleaner and the concentration at which it is prepared, the
solvent may serve only to reduce the viscosity of the contaminants to
make them more readily dispersable by detergents that may be compounded
into the product as part of the emulsifying system.    The size and
geometry of the part and the nature of the contaminant are the main
criteria for selecting between the use of immersion or spray cleaning
techniques.
2.3.2.2  Method of Substitution
     As in the case of aqueous cleaning equipment, use of emulsion cleaners
as a substitute system for a vapor degreaser would necessitate the replacement
of the degreaser and any associated support equipment.  Substitution of
                                   2-19

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emulsion cleaners for halogenated solvents would not require the replacement
of most cold cleaning equipment because most manufacturers of cold cleaning
machinery have designed the ability to use emulsion cleaners into their
                                      13 14 34
equipment to increase its versatility.  '   '
     The use of emulsion cleaners requires no special  technical  skills
beyond those required for straight solvent cleaning operations.   The
ability of most cold cleaning machines to  use emulsion cleaners  inter-
changably with solvents would not necessitate any gross changes  in a
metal cleaning operation such that a greater degree of expertise would be
required of the user to effectively employ the emulsion cleaner.  Additionally,
substitution would involve only the changing of cleaning medium  within a
system.  The time required for conversion  to this substitute would be
minimal, and it is not anticipated to interfere to any significant degree
in its implementation.
2.3.2.3  Degree of Substitution
     Emulsion cleaners were developed to fill the gap  between solvent
vapor degreasing and alkaline cleaning.  Subsequent research and development
has produced water-based cleaners that have been designed to replace
products such as petroleum solvents and halogenated solvents. As a
result, many emulsion cleaners can be used to remove the same types of
                                                             35
contaminants that are removable by the solvents they replace.    Emulsion
cleaners are suitable for use on most metals because of their neutral to
slightly alkaline pH.  The most widespread use of emulsion cleaners is
for the in-process cleaning of metal parts to remove contaminants such as
pigmented and unpigmented drawing compounds, lubricants, cutting fluids,
and metal chips that may be acquired in a  variety of machine-based production
systems.  In these applications, emulsion  cleaners act as a partial
substitute because they offer a means of achieving rapid superficial
cleaning of parts throughout manufacture and assembly.  According to
comments received by DuPont (Appendix A),  emulsion cleaning is not an
alternative to CFC-113.  Water, unless doped wth surfactants, has a high
surface tension (72 dynes/cm vs. 17.3 dynes/cm for CFC-113 at 25°C)
and thus does not wet surfaces or penetrate interstices as well.
                                   2-20

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     The most important characteristic of all  emulsion cleaners  is  that
they deposit a light film of residual  oil onto metal  parts  as  they  emerge
from the cleaning process.  Depending  on the application involved,  this
oil film can be extremely valuable in  that it provides a significant
degree of rust protection for metal  parts during their fabrication  and
assembly.  It also helps ensure the corrosion resistance of parts  that
undergo several weeks of storage before being assembled or  shipped.
However, for manufacturing, maintenance, or repair operations  that  require
processed parts to be free of any oil  residue, emulsion cleaners should
not be substituted.  Subsequent cleaning by another method  such  as  alkaline
washing would be necessary to achieve  a totally clean part.  Depending on
the particular cleaning requirement, the use of emulsion cleaners  would
only be effective as a precleaning agent prior to final processing  by
another cleaning system.
     In 1976, approximately 15 percent by volume of all metal  cleaning
compounds used domestically were emulsion cleaners.    Most manufacturing
or maintenance operations in which metal parts undergo sequential  machining
followed by cold cleaning with halogenated solvents prior to final  assembly,
storage, or shipment, can be considered as candidates for substitution
with an emulsion cleaner.  For the purposes of this study,  contact was
made with a manufacturer of cold cleaning machinery and emulsion cleaning
compounds to assist in the identification of emulsion cleaner users so
that a profile of current applications using emulsion cleaners could  be
developed.  Based on the response received the large degree of interchangeability
of emulsion and solvent-based cleaning media prevented identification of
                                                                              23
companies using emulsion cleaners in manufacturing and maintenance operations.
However, literature review indicated the following examples in which
emulsion cleaning has been employed in applications that traditionally
have employed  solvents:
     •    Cleaning and coating of welded auto wheels prior to shipment,
     t    Cleaning and protection of engine blocks prior to assembly,
     •    Steel sheet metal cleaning and coating for rust  protection,
                                    2-21

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     t    Cleaning and rust protection of bearings  in  process  and  before
          final  assembly, and
     •    Cleaning of aluminum reflectors.

     Emulsion cleaners have been chosen for these and  similar  tasks  because
they are usually less expensive to use, less toxic, easier to  treat  and
dispose of, and offer a longer working life than the solvents  they replace.
     As mentioned above, emulsion cleaners generally are not well  suited  to
providing "chemically" clean surfaces due to their tendency to deposit a
thin oil film on parts emerging from the cleaning process.  Hence, emulsion
cleaners do not represent a technically viable substitute for  vapor
degreasing operation because vapor degreasing is usually chosen for  its
ability to produce a part with surfaces devoid of any  significant  amount  of
grease or oil.  Thus, for any application in which the absence of  any
chemical residue is critical, emulsion cleaning could  not be considered a
technically feasible substitute for halogenated solvents since any emulsion
cleaner chosen would not produce a product of acceptable quality.   Many
manufacturing processes in the microelectronics industry for example cannot
tolerate the light oil film that is characteristic of  emulsion cleaners and
so use solvent and/or aqueous cleaning systems.  Parts destined for  later
finishing, such as in electroplating, may require a secondary  solvent or
aqueous cleaning following an initial emulsion cleaning to remove  unwanted
surface oils.  Analogous cleaning situations exist in  the manufacture of
many sophisticated electromechanical devices such as medical machinery,
missle propulsion systems, and photographical equipment.  The  cleaning
requirements of these devices are similar in that halogenated  solvents
frequently possess the most complete and compatible set of properties
necessary to ensure reliable product performance.
     As with an aqueous system, emulsion cleaning generally requires
more space and energy than vapor degreasing systems.  Although emulsion
cleaning does provide some ability to solubilize solvent soluble soils
compared with an aqueous system, the solvent portion of the emulsion is  a
relatively small percentage, and the ability to dissolve solvent soluble
soils before saturating the emulsion cleaner is limited.
                                    2-22

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2.3.2.4  Resource Availability
     Major manufacturers of both solvent and aqueous  cleaning  equipment
are also the principal  suppliers of emulsion cleaners.   As  in  the  case of
aqueous cleaning systems, growth in the market for emulsion cleaners  is
about 10 percent annually with adequate production capacity in reserve to
                                              23 28 29  30
handle a two to three fold increase in demand.  '   '   '
2.3.3  Nonchemical Cleaning
2.3.3.1  Process Description
     The principal nonchemical substitute for solvents  used in metal
cleaning operations is abrasive blasting.  Abrasive blasting relies  on
the mechanical energy of impacting particles to remove  contaminants  from
a variety of parts and materials.  Particles are entrained  in  a moving
carrier medium such as air or water, and then directed  against the surface
of the work being processed.  The cleaning effectiveness is a  function of
the particle's abrasive properties, hardness, size, and energy of  impact.
     Materials commonly used as abrasives include silica sand, steel
grit, aluminum oxide, nut shells, and glass beads.  Selection  of a suitable
abrasive for a specific application is influenced by the type  of surface
contamination to be removed, the size and shape of the  work piece, the
                                                    38
finish desired, and the rate of production required.     Cleaning done by
abrasive blasting materials is nonselective with respect to the type of
surface being cleaned since no chemical mechanism for contaminant  removal
                           39
is involved in the process.
     Abrasive blast cleaning may be done by portable equipment which can
be moved from job to job, or done in specially designed, sealed compartments
Portable blasting equipment is used for the cleaning of large objects
such as storage tanks, bridge superstructures, and construction equipment.
Blasting systems which use enclosed compartments are designed to clean
medium to small size work pieces which can be transported to the blasting
system for  processing.  Self-contained blasting systems can be used to
clean  such  objects as engine heads, water meters, and die castings.
                                    2-23

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2.3.3.2  Method of Substitution
     Use of abrasive blasting equipment,  whether portable or self-contained,
as a substitute method for cleaning with  halogenated solvents,  would
necessitate the replacement of the solvent-based cleaning equipment.
However, as the subsequent section illustrates, no significant  degree of
technical interchangability exists between vapor degreasing and abrasive
blast cleaning processes.  Consequently,  only those cold cleaning operations
using halogenated solvents would be possible candidates for substitution
to the use of a blast cleaning system.  The greatest potential  for substitution
would be through the use of self-contained, compartmentalized blasting
systems capable of cleaning small to medium size workloads of simple
geometry.
     Contact with a leading manufacturer of abrasive cleaning systems
indicated that the time required to deliver a complete blasting system
was  approximately 8 to 12 weeks depending on seasonal demand and backorder
status.40  Installation of the equipment is straightforward and requires
only a  115 to 230 volt service connection depending on the size of equipment
chosen.  The degree of technical skill required to operate the substitute
system  is minimal and consists mainly of selecting the correct air pressure
used to  propel the  abrasive media  such that the impacting  particles do
not  possess kinetic energies  in excess of those required for the specific
cleaning application.
2.3.3.3 Degree of  Substitution
     Abrasive  blasting systems require a high  level of manual  operation
in order to clean  parts  adequately.   Portable  blasting systems must be
transported to  the  site  where cleaning is  to occur while stationary
systems must  be  handloaded with  separate  parts, each  needing individualized
cleaning to assure  an effective  result.  Additionally, abrasive  blasting
systems are used  to remove contaminants  other  than  oils  and  greases  such
as corrosion  products, heat  scale, and carbon  deposits,  which  due  to
their  respective  chemical  structures  are  not attacked readily  by solvents.
 In consideration  of these and other constraining  factors,  portable and
 stationary abrasive blasting systems  offer no  significant  degree of
 technical  substitutability for  the vapor degreasing cleaning process.

                                    2-24

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     Stationary abrasive blasting systems do possess  a  sufficient  degree
of cleaning utility to be considered a limited substitute  for  some cold
cleaning applications using halogenated solvents.   The  greatest  degree of
overlap between cold solvent cleaning and abrasive blasting  occurs in the
cleaning of internal combustion engine parts and related components prior
to maintenance, rebuilding, and repair operations.  Parts  such as  piston
rods, pumps, connecting rods, and valves may be blasted clean  under
suitably controlled conditions of particle size, hardness, and impact
velocity without alteration of critical tolerances.  Critical  cleaning of
electronic, medical, and other equipment containing small  interstices and
close-packed electronic assemblies cannot be cleaned  by blast  cleaning.
     The key to the successful use of blast cleaning  in these  applications
is the selection of an appropriate cleaning medium.  Glass beads generally
are chosen for the cleaning of precision parts.  When used properly,
abrasion of surface metal is negligible.  The beads resist becoming
imbedded in the surface being cleaned due to their sphericity.  However,
because blast cleaning is unable remove contaminants  from metal  parts
containing complex internal passages, such as the gasoline passages in a
carburetor, the extent to which blasting can be considered a technically
viable substitute for cold cleaning with halogenated  solvents  is restricted
                                             41
to a relatively small number of applications.
2.3.3.4  Resource Availability
     Published information concerning the abrasive cleaning industry is
limited.  Contact with a major manufacturer of both portable and stationary
blasting systems indicates that capacity and usage estimates for abrasive
blast cleaning machinery are not available.    However, the same manufacturer's
product literature indicates that past and current abrasive blast cleaning
equipment customers are located in a variety of industries including
chemicals, steel, and rubber.  However, it appears unlikely that blast
cleaning is being used for most of the same applications as solvent
cleaning in these industries.  Nevertheless, the demand from these user
industries for blast cleaning equipment, even if destined for other
cleaning applications not compatible with solvents, tends to indicate
that sufficient capacity exists to service the small  increase in demand
                                   2-25

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anticipated to result from any degree of substitution using these
nonchemical cleaning systems.
2.3.4  Cleaning with Other Organic Solvents
2.3.4.1  Process Description
     Solvent metal cleaning uses organic solvents to remove a wide variety
of contaminants from the surfaces of parts being processed in manufacturing,
maintenance, and repair operations.  Examples of typical  contaminants
susceptible to solvent removal include most greases, oils, and waxes  as
well as an assortment of resins and polymers.  Solvents used for these
purposes may be grouped into four broad categories:   aliphatic, aromatic,
oxygenated, and halogenated.  The last category includes  a large number  of
brominated, fluorinated, and chlorinated hydrocarbons suitable in  varying
degrees for use as metal cleaning solvents.  Trichloroethylene, perchloro-
ethylene, 1,1,1-trichloroethane, methylene chloride, carbon tetrachloride,
and trichlorotrifluoroethane are all members of the  halogenated solvent
category.
2.3.4.2  Method of Substitution
     The use of substitute organic solvents in those cold cleaning
applications employing halogenated solvents will not, for most users,
entail any extensive modification of existing solvent cleaning equipment.
Substitution for the majority of users of cold cleaning processes  would
involve only the changing of one solvent for another.  Several factors
combine to promote a significant degree of solvent interchangability.
These factors include:
     •    The moderate to high solvency exhibited by most organic  solvents
          for commonly encountered industrial contaminants;
     •    The chemical compatibility of most organic solvents for  almost
          all ferrous and nonferrous metals;
     e    Insensitivity of most cold cleaning techniques  such as hand-
          wiping and immersion to the type of solvent used; and
     •    The ability of most cold cleaning equipment to  operate effectively
          and clean adequately with a variety of solvents typically used
          in metal cleaning applications.
                                  2-26

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     While the above factors  assure that in  many applications  one or more
substitute solvents may be able to perform adequately as  a  replacement
for a halogenated solvent in  a specific cold cleaning operation, the
ability to use a substitute solvent is not universal  for  all  types  of
cold cleaning equipment.  Conveyorized cold  cleaning  machines  such  as
those designed for use as in-line printed circuit board defluxers could
not convert to the use of a substitute organic solvent because their
enclosed design would tend to accumulate potentially  explosive amounts of
solvent vapor.  Additionally, the inability  of many solvents  to remove
the specialized solder fluxes used in the manufacture of  printed circuit
boards (without imparting damage to the board substrate)  minimizes  the
potential for large scale use of substitute  organic solvents  in much of
the microelectronics industry.  Substitution of aliphatic,  aromatic, and
oxygenated solvents may not satisfy cleaning requirements in  critical
cleaning applications.
     The substitution of cold cleaning with  other organic solvents  for
vapor degreasing would necessitate the acquisition of new cleaning  equipment
due to the distinct differences in the nature of the cleaning processes.
For cold cleaning equipment to approach vapor degreasing  in cleaning
efficiency, large amounts of solvent agitation are necessary  to make up
for the absence of the high heat input that underlies vapor degreasing's
cleaning effectiveness.  Because many vapor degreasers do not contain  any
solvent agitation mechanism, they could not be used as cold cleaning
machines.  Owners of vapor degreasers would have to replace their  existing
equipment with cold cleaning machinery of comparable production capability.
     Due to the unique combination of physical and chemical properties
that a solvent must possess in order to function properly in  the vapor
degreasing process, much less latitude exists for substituting other
organic solvents  in vapor degreasing applications than for cold cleaning.
A  partial list of those solvent characteristics of particular importance
to vapor degreasing include:
                                    2-27

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     •    High vapor density relative to air,
     •    Chemically stable, nonflammable, and nonexplosive under operating
          conditions,
     •    Low latent heat of vaporization and low specific heat  so that a
          maximum amount of solvent will condense on a given mass of
          metal  and keep heat input requirements to a minimum,
     •    Boiling point low enough to permit the solvent to be easily
          separated from contaminants by simple distillation but high
          enough to allow sufficient solvent vapor condensation  on the
          work to insure adequate cleaning, and
     t    Low toxicity.
     Currently,  there is only one other halogenated solvent capable of
meeting the above criteria:  trichlorofluoromethane (CFC-11).  Trichloro-
fluoromethane has solvent characteristics that closely approximate those
of trifluorotrichloroethane (CFC-113).   This functional  similarity has
enabled it to be used for some of the same critical cleaning applications
as CFC-113, such as in the cleaning of delicate electromechanical  parts
and chemically sensitive plastics such as polycarbonates.   However, the
relatively low boiling point of CFC-11  (24°C), and concern over  its ozone
depletion potential historically has prevented any widespread vapor
degreasing applications.  Nevertheless, experimental vapor degreasing
systems have been designed around CFC-ll's thermodynamic properties.
Results of prototype testing indicate that CFC-11 can be used successfully
to remove most common metal working contaminants with the  exception of
                         42
high melting point waxes.    Substitution of CFC-11 for other vapor
degreasing solvents would necessitate reducing the heat input into the
degreaser and supplying additional  cooling capacity (to help prevent
excessive solvent losses from diffusion) through addition  of a refrigerated
freeboard device.
     Little or no increase in the degree of technical  skill  would be
required to operate a cold cleaning system using nonhalogenated  solvents
as opposed to a  similar system using halogenated solvents.  In many
cases, the same  equipment can be used for either type of solvent so that
no new skills need be acquired and no installation of new  equipment will
                                   2-28

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be necessary.  The length of time required to make a substitution  for
nonhalogenated for halogenated solvent would be minimal  because  no new
equipment would be acquired and the widespread availability of alternative
solvents would not create any significant downtime for most solvent
cleaning operations of this type.  Substitution of a cold cleaning system
using alternative organic solvents for a vapor degreasing system would
vary widely with respect to the time needed to implement the substitution.
Process variables including production volume, load handling systems,  and
workload geometry may necessitate some degree of custom engineering,
which could increase the time required to achieve the substitution.
However, based on contacts with manufacturers of cold cleaning equipment,
the time required to procure the substitute cleaning system would  be  the
same as that needed to substitute an equivalent aqueous-based cleaning
process.  Even in the case where extensive custom engineering is indicated,
the time necessary to design, construct, deliver, and install the  substitute
system is not expected to exceed 20 weeks.
2.3.4.3  Degree of Substitution
     Industrial cold cleaning applications exhibit such a great  amount  of
diversity with respect to process variables such as the physical and
chemical properties of objects being cleaned, type of contaminant  removed,
production volume, and cleaning equipment used, that no single solvent
can be adapted for all purposes.  Many situations exist in the cold
cleaning of metal parts where replacement of a halogenated solvent with
another organic solvent is possible.  Drawing compounds, cutting and
grinding fluids, some polishing and buffing compounds, and miscellaneous
contaminants, such as metal chips, dirt, and corrosion inhibitors, are
all amendable to cleaning processes using nonhalogenated solvents.  Most
manufacturing operations requiring the removal of these common metal
working compounds and by-products prior to further processing or assembly
are candidates for cleaning with nonhalogenated solvents.  Because the
majority of manufacturing operations using cold cleaning employ  relatively
simple techniques such as immersion and manual scrubbing, there  is ususally
sufficient latitude within the process to allow the use of several substitute
solvents on an equivalent basis.  Opportunities for substitution also
                                    2-29

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exist for many users of halogenated solvents located  in  the  maintenance
and service sectors of the economy.  Sectors such as  engine  repair,
office machinery, and machine tool  rebuilding possess similar  requirements
that are adequately fulfilled by cold cleaning with nonhalogenated  solvents.
     The high degree of solvency offered by substitute organic solvents
for commonly used metal forming and drawing compounds frequently  offers  a
user several candidate solvents from which to choose  the most  suitable to
the particular application.  Other factors which influence the choice of
a substitute solvent include solvent cost, flash point,  toxicity, flammability,
and evaporation rate.  Different users will weigh each of the  above
factors differently in accordance to their particular application or
experience.  For example, one user may consider evaporation  rate  more
important than toxicity, while another user with a similar cleaning
requirement may consider solvent cost to be the most  important criterion.
Examples of some metal cleaning solvents which find widespread applicability
in cold cleaning operations are listed in Table 2-4.
     While the ability to substitute other organic solvents  for halogenated
solvents exists for a number of manufacturing and maintenance  operations,
some specialty applications requiring extremely low residue  contents
following cleaning are not particularly well suited  to  solvent substitution.
Aerospace, nuclear, and other precision industries frequently  demand
white-room techniques which necessitate ultra-pure cleaning  requirements
not readily met by cleaning media other than halogenated solvents.
Examples of exacting applications not particularly suited to solvent
substitution include the maintenance of nuclear fuel  handling  equipment,
cleaning of hydraulic systems, and the cleaning of high-tolerance injection
molds.
     Vapor degreasing is generally chosen over cold cleaning when it is
perceived that a fairly high degree of cleanliness is required and  that
there exists a production volume of sufficient magnitude to  justify the
larger capital expenditure for vapor degreasing machinery.   Hence,  for
cold cleaning with other organic solvents to be a viable substitute for
vapor degreasing, the choice of an appropriate cold cleaning system
capable of both a high level of cleanliness and of handling  a  large
                                   2-30

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TABLE 2-4.  COMMON METAL CLEANING SOLVENTS41'42
Solvent
class/solvent
Oxygenated Hydrocarbons
Me t ha no 1
Ethanol
Isopropanol
Acetone
Methyl Ethyl Ketone
Aliphatic Hydrocarbons
Petroleum solvents
Cyclohexane
Aromatic Hydrocarbons
Toluene
Xylene
Halogenated Hydrocarbons
Chlorobenzene
o-Dlchlorobenzene
Trichlorofluoromethane (CFC-11)
Threshold
limit
value
(ppm)

200
1,000
400
1,000
200

200-500
300

200
100

75
50
1,000
Flash
point

58
60
70
3
28

M05
10

40
81

80
165
none
Flammable limits,
% by volume in
air at 20°C
Lower

6.0
3.3
2.7
2.2
1.8

0.8
1.4

1.3
1.1

1.3
2.2
Upper

36.5
19.0
12.0
13.0
11.5

6.0
8.4

7.0
6.6

7.1
9.2
Relative
evaporation
rate (n-Butyl
acetate = 1)

3.5
1.9
1.7
7.7
4.6

0.2


1.5
0.75

1.07
0.15
nonflammable
Pounds
per
gallon
at 68°F

6.60
6.62
6.57
6.59
6.71

6.43
6.52

7.26
7.25

9.19
10.84
12.42
Price per
pound
(first
quarter 1981)

$0.82
0.28
0.29
0.29
0.35

0.25
0.30

0.21
0.21

0.36
0.50
0.47

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production volume is important.  Several manufacturers of industrial  cold
cleaning machinery have recognized these criteria and have engineered
cleaning systems capable of processing comparable workloads with a cleaning
effectiveness comparable to that of vapor degreasing.  High flash point
cleaning media such as petroleum solvents are typically used in these
applications.  Such equipment substitutes high levels of mechanical
agitation for hot solvent vapor in order to achieve a degree of cleaning
effectiveness comparable to vapor degreasing.  Typical cold cleaning
systems of this type process large workloads (up to several thousand
pounds of parts per single workload) by pneumatically agitating them  up
and down in the solvent at speeds in excess of 130 times per minute.
The induced motion of the solvent provides a higher level of cleaning
effectiveness relative to spray or flushing techniques common on smaller
manually operated cold cleaning machines.
     These larger types of cold cleaning equipment have found wide scale
use in those industries which are also the principal  users of vapor
degreasing processes such as the transportation, printing, reconditioning/rebuilding
and metal working industries.  Particular fields of application in the
metal  working industry include metal fabricating, machine shop operations,
screw machine parts manufacturing, and tool and die production.  Several
of the manufacturers offer custom designs for specialized cleaning needs
and consider the market for the equipment they produce to be fundamentally
the same as that of the manufacturers of vapor degreasers.       While
there would still exist vapor degreasing applications for which substitution
of cold cleaning with other organic solvents would not be technically
feasible (such as microelectronics), many current users of vapor degreasing
could regard this type of cold cleaning machinery as  a substitute capable
of high cleaning efficiencies for large production cleaning requirements.
     The use of azeotropic mixtures of halogenated and nonhalogenated
solvents offer a degree of partial substitutability to the use of pure
halogenated solvents as vapor degreasing agents.   An  azeotropic solvent
mixture is a combination of several  component solvents which boil  at  a
constant temperature such that the resulting vapor is of the same chemical
composition as the original  liquid.   An azeotropic solvent mixture can be
                                   2-32

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used in a vapor degreaser without fear that the relative percentage of
each component in the mixture will  be altered during the cleaning process.
The use of azeotropic solvent mixtures in vapor degreasing is fairly
common.  Azeotropic solvent mixtures generally possess synergistically
enhanced cleaning characteristics that may be more effective than those
of a pure solvent for removing a particular contaminant.  Examples of
azeotropic solvent mixtures used in vapor degreasing include a 70 percent/30 percent
blend of trichloroethylene with isopropanol or a 96 percent/4 percent
                                                         46
blend of trichlorotrifluoroethane with denatured ethanol.     For the
majority of vapor degreasers, use of a solvent azeotrope will not entail
the retrofitting of any new solvent control or recovery equipment.
Additionally, little if any modifications in cooling capacity would be
required.  Thus, azeotropic solvent mixtures, while not completely replacing
one of the five standard vapor degreasing solvents, can reduce the amount
used in vapor degreasing and thereby offer a partial substitute to the
use of the pure compounds.
     The use of the halogenated solvent trichlorofluoromethane (CFC-11)
as a vapor degreasing agent offers the potential of being a complete
substitute cleaning compound for many degreasers using trichloroethylene,
1,1 ,1-trichloroethane, methylene chloride, and trichlorotrifluoroethane
(CFC-113).  CFC-11 will not, in most cases, be a viable substitue for
vapor degreasers using perchloroethylene because its substantially lower
boiling point (24°C compared to 121°C for perc) would not adequately
remove high melting point waxes which usually require processing with
perchloroethylene.  However, it is estimated that only about ten percent
of all open top vapor degreasers and conveyorized degreasers currently
                      47
use perchloroethylene.
     CFC-11 has not been widely used as a vapor degreasing solvent because
of its high volatility and ozone depletion potential.  However, one major
producer of both CFC-113 and CFC-11 has conducted prototype testing with
modified vapor degreasers for use with CFC-11 to evaluate its potential
                            42
as a metal cleaning solvent.    Results of that study indicated that
CFC-11 can be used effectively as a vapor degreasing solvent to remove
the same types of industrial contaminants as the other degreasing solvents
                                   2-33

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(except as previously noted).  Follow-up contacts with the producer were
initiated to determine the feasibility of retrofitting existing vapor
                                        48
degreasers to enable them to use CFC-11.    According to the producer,
most existing vapor degreasers could be adapted for use with CFC-11
through the adjustment of the heat balance needed to maintain the boiling
solvent and the addition of a refrigerated freeboard device.  Due to
differences in the physical properties of each solvent, the extent of the
modifications necessary to enable a vapor degreaser to use CFC-11 will
vary depending on the solvent the degreaser was using prior to substitution.
2.3.4.4  Resource Availability
     Based on contacts with major producers of both halogenated and
nonhalogenated solvents, sufficient capacity exists to meet large scale
                                               48 49
increases in demand for either type of solvent.  '    Previous contacts
with manufacturers of refrigeration devices for vapor degreasing equipment
as well as contacts with cold cleaning manufacturers capable of processing
large production volumes indicate that sufficient capacity exists in both
sectors to meet significant increases in demand for either type of
equipment.28'29'30'50
2.4  ECONOMIC ANALYSIS OF SUBSTITUTES
2.4.1  Background
     This section analyzes the economic feasibility of substituting
alternative cleaning processes for cold cleaning and vapor degreasing
operations that use trichloroethylene, perchloroethylene,  methylene
chloride, 1,1,1-trichloroethane,  trichlorotrifluoroethane, and carbon
tetrachloride.  The substitutes analyzed are aqueous cleaning, emulsion
cleaning, nonchemical  cleaning and cleaning with other organic solvents.
For the purposes of this study, the economic analysis deals only with
estimating the relevant costs of  using substitutes.   No attempt is made
to assess the user's ability to pay these costs.  The cost categories
analyzed are costs related to a decline in product quality, and the
capital and annualized operating  costs of using substitutes.
                                   2-34

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2.4.1.1  Industry Structure
     Metal cleaning is not a distinct industry, but rather it is part of
the production process utilized in most industries which manufacture,
maintain, and repair metal parts and products.  These industries are
located throughout all geographic regions.  The size of businesses  which
clean or degrease metal  parts and products range from small  neighborhood
service stations to large plants, such as in the aircraft and automobile
industries.  Table 2-5 illustrates the types of industries which use
metal cleaning operations in California.
2.4.1.2  Market Share of Substitutes
     Aqueous cleaning, emulsion cleaning, nonchemical cleaning and
cleaning with solvents other than the halogenated solvents listed above
are all in present use.   Figure 2-1  shows the market share of each  substitute,
Of the four processes, aqueous cleaning systems, particularly alkaline
washers, are the primary substitute for vapor degreasing.  Discussions
with respective manufacturers indicate that they are competing in the
                                14 15
same markets with their product.  '     Table 2-3 shows the use of solvent
and alkaline cleaning systems by Standard Industrial Classification.
Overall, it is estimated that aqueous cleaning represents 39 percent of
                                52
the total metal cleaning market.    Industries which use aqueous cleaning
to a large extent include metal furniture, fabricated products, and
transportation equipment.
     Unlike aqueous cleaning systems, emulsion cleaners cannot be substituted
for halogenated solvents in as many given cleaning situations.  This is
generally because of the need for a processed part that is devoid of any
surface oil or residue.   Nevertheless, emulsion cleaners are frequently
used in metal cleaning operations, particularly when a chemically clean
surface is not required and when rust protection is a desired result of
the cleaning process.  Approximately 15 percent of the metal  cleaning
compounds used in this country are estimated to be solvent emulsions.
     Of the four substitute cleaning methods identified, nonchemical
cleaning has the smallest market penetration.  Nonchemical cleaning
systems are used principally to remove contaminants other than oils and
                                   2-35

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TABLE 2-5.   SUMMARY OF CERTAIN CALIFORNIA INDUSTRIES USING
            SOLVENT CLEANING OPERATIONS51
SIC
332
342
344

346
347
349
351
356
359
366
367
369
371

372
376
Category
Iron & Steel Foundries
Cutlery, Handtools
Fabricated Structure
Metal Products
Forgings & Stampings
Metal Services
Misc. Fabricated Metals
Engines and Turbines
General Machinery
Misc. Machinery
Communicating Equipment
Electronic Components
Misc. Electrical
Motor Vehicles &
Equipment
Aircrafts & Parts
Guided Missies, Space
No.
of
companies
150
712

2,201
587
1,065
1,093
114
949
5,988
957
2,083
500

1,101
551

Percent of
companies
using
degreasing
37
25

5
4
55
18
100
45
33
48
40
33

45
60

No. of
companies
using
degreasing
56
178

110
23
586
197
114
427
1,996
459
833
167

495
331

    Vessels
43
75
32
                           2-36

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                                AQUEOUS
                                CLEANING
                                  (39%)
HALOGENATED
  SOLVENT
  CLEANING
    (34%)
                                  EMULSION
                                  CLEANING
              NONHALOGENATED
              SOLVENT CLEANING
                    (24%)
NONCHEMICAL
  CLEANING
    (3%)
  Figure 2-1.  Market share of metal cleaning techniques.
                                           52
                        2-37

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greases, such as corrosion  products,  heat scale,  and carbon  deposits.
Nonchemical  cleaning can be used to clean internal  combustion  engine
parts prior to rebuilding and repair operations.     This  is  one  of  the
few areas where substitution for halogenated solvents is  possible.   The
market penetration of nonchemical  cleaning has been estimated  to be less
               52
than 3 percent.
     Cleaning with organic solvents other than trichloroethylene, perchloroethylene,
methylene chloride, 1,1,1-trichloroethane, trichlorotrifluoroethane,  and
carbon tetrachloride is  predominantly done in cold cleaning  systems,
except for trichlorofluoromethane which is a direct substitute in vapor
degreasing operations.  However, because of the high volatility  and cost
of trichlorofluoromethane relative to the chlorinated solvents,  its use
is limited to specialty cleaning applications.
     Nonhalogenated solvent cleaning operations make up approximately
                                              52
24 percent of the total  metal cleaning market.    Cold cleaning  solvents
include:  acetone, cyclohexane, ethanol, isopropanol, methanol,  methyl
ethyl ketone, petroleum solvents, toluene, and xylene.  Table 2-6 shows
the  percentages of halogenated  and nonhalogenated solvents used in metal
cleaning operations.
2.4.1.3  Growth Trends
     Growth  in  metal cleaning is directly related to the growth of those
industries  in which  it pays a prominent  role.  Table 2-7 lists the major
users of degreasing  equipment according  to expenditures.  Since manu-
facturers of aqueous cleaning equipment  and  nonchemical cleaning equipment
compete in  the  same  market, the data from Table  2-7  can be used as a
proxy for  the  projected  growth  of  the  substitutes.   The number of  cold
cleaners and vapor  degreasers,  respectively,  is  expected to grow by over
20 percent  between  1980  and 1985.  This  is based on  data supplied  by the
Bureau  of  Labor Statistics which  project average annual growth  rates of
over 4  percent  for  industry groups using metal cleaning.
                                   2-38

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TABLE 2-6.   NATIONAL DECREASING SOLVENT CONSUMPTION53
Solvent type
Halogenated:
Trichloroethylene
1,1,1-Trichloroethane
Perchloroethylene
Methyl ene Chloride
Tri chl orotri f 1 uoroethane

Aliphatics
Aromatics:
Benzene
Toluene
Xylene
Cyclohexane
Heavy aromatics

Oxygenated:
Ketones:
Acetone
Methyl Ethyl Ketone
Alcohols
Ethers

Total Solvents
Solvent consumption,
Cold Vapor
cleaning degreasing

0.6 13.5
14.0 10.5
2.1 4.8
4.6 2.2
1.2 5.5
22.5 36.5
30.7

1.0
1.9
1.7
0.1
1.7
6.4


1.4
1.1
0.7
0.8
4.0
63.5 36.5
percent
All
degreasing

14.1
24.5
6.9
6.8
6.7
59.0
30.7






6.4






4.0
100.0
                       2-39

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                  TABLE 2-7.   GROWTH  TREND  FOR  DECREASING  FOR  SELECTED  INDUSTRY  GROUPS
                                                                                                             a,54
Total
Standard degreaslng
Industrial cost - 1976
classification (10« $)
344 Fabricated Structural
Metal Products
354 Hetalworklng
Machinery
356 General Industrial
Machinery
359 Misc. Machinery,
Except Electrlal
372 Aircraft and Parts
382 Measuring and
Controlling Devices
458 Air Transport -
Maintenance
ix) 753 Auto Repair
S TOTAL
Incremental change
100
150
150
294
108
105
195
1,796
(«)
Number of .
cold cleaners
1976
25.131
38.152
30.734
79,547
11,967
17,797
36,160
468,027
707,515

1980
29,287
45,671
40,286
103,105
13,786
23,241
48,832
518,633
822.841
16.3
1985
35,291
52,689
55.195
118.948
17,594
26.943
66.278
627.969
1,000.907
21.6
Number of
open top
vapor degreasers
1976
771
569
1,876
1.085
2,779
3,194
3,279
0
13,553

1980
899
681
2.459
1.406
3.201
4.171
4,428
0
17,245
27.2
1985
1.083
786
3,369
1,622
4,086
4,835
6,010
0
21.791
26.3
Number of
conveyor) zed
degreasers
1976
187
122
402
232
393
187
0
0
1.523

1980
218
146
527
301
453
244
0
0
1.889
24.0
1985
263
168
722
347
578
283
0
0
2.361
24.9
Growth
ratec
1976-
80
3.9
4.6
7.0
6.7
3.6
6.9
7.8
2.6

1980-
85
3.8
2.9
6.5
2.9
5.0
3.0
6.3
3.9

 These represent all Industrial groups using metal  cleaning with expenditures  in excess of $100 million in  1976.
 Includes  all cold cleaners using halogenated and nonhalogenated solvents.
GBureau of Labor Statistics estimated and projected growth rate.

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2.4.2  Product Quality
     Product quality in metal cleaning is determined by the degree to
which a process satisfactorily cleans specific items.  Costs associated
with a decline in product quality are the expenses associated with
re-cleaning an item.  Generally, these expenses include additional energy
consumption, labor, cleaning material, and the opportunity cost of
foregoing cleaning new items while re-cleaning takes place.
2.4.2.1  Cold Cleaning With Halogenated Solvents Versus Alternatives
     Automobile repair is the largest single industry group using cold
cleaning operations.  Cold solvent usage may range from wiping a part
with a solvent soaked rag to the use of automated systems complete with
pump, filtration and distillation equipment, and auxiliary storage tanks.
Halogenated solvents are not used extensively in service and maintenance
sectors such as automotive repair due to their high cost, volatility, and
tendency of several to degrade painted surfaces.  However, mixtures
containing halogenated solvents are employed in small maintenance cold
cleaners which are used to clean carburetors and other automotive parts.
One such mixture marketed by Safety-Kleen Corporation contains a blend of
methylene chloride, ortho-dichlorobenzene, and cresylic acid, covered by
                         55
an aqueous soap solution.    The exact composition of solvent blends is
usually proprietary and is believed to vary from product to product and
from company to company.
     Automotive repair operations generally do not require chemically
clean surfaces that halogenated solvents may provide.  For this reason,
the use of an alternative organic solvent such as a petroleum solvent can
be used by this sector with no decline in product quality and consequently
no additional costs.  The ability to chose between other organic solvents
is the principal form of substitution for this major user industry.
Depending upon the application, aqueous cleaning can also be used with
acceptable results although additional captial costs would be incurred by
those solvent users who do not possess cold cleaning equipment compatible
with aqueous cleaning media.  The largest portion of these capital  costs
would be for the acquisition of new cleaning equipment.
                                   2-41

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     There are certain critical cold cleaning operations for which there
are apparently no acceptable nonhalogenated solvent substitutes.  These
critical cleaning applications involve certain electromechnical  components.
Examples include some semi-conductor products; nuclear fuel handling
equipment; oxygen breathing apparati; precision medical equipment; and
fuel storage tanks for aerospace applications.  In these applications,
halogenated solvents have a unique set of chemical and physical  properties
required for such precise cleaning tasks.  In such cases, substitution
with nonhalogenated solvents would likely cause a decline in product
quality such that costs arising from using a substitute could be prohibitive,
2.4.2.2  Vapor Degreasing Versus Alternatives
     The primary substitute for vapor degreasing is alkaline washing.   In
a 1978 study by Eureka Laboratories, Incorporated, cost data were compiled
from the comparative operations of a vapor degreaser and an alkaline
washer.  Each system cleaned 100 metal  cabinets weighing 100 pounds
apiece.  It was estimated that 2 percent of the cabinets cleaned by the
alkaline washer were rejected and had to be re-cleaned.  It was  estimated
that re-cleaning cost four times the original  cleaning expense.   For this
specific case, the expense amounted to $9,390 (1978 dollars), approximately
10 percent of the total  operating costs.  The Eureka study also  cited  the
comparison of a vapor degreaser and an emulsion cleaner.  The results
were generally the same as with the alkaline washer.  Two percent of the
parts cleaned by the emulsion cleaner were rejected.  Re-cleaning the
parts cost 4 times the original cleaning cost.
     It must be noted, however, that the above comparisons represent
case-specific tests which may not reflect current technology. Similar,
more recent tests have not been conducted.  Because alkaline washer
manufacturers often custom-build their systems for a specific cleaning
need, it is unlikely that costs associated with a decline in product
quality would prohibit substitution.
                                   2-42

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2.4.3  Capital and Annualized Operating Costs
2.4.3.1  Alternatives to Cold Cleaning With Halogenated Solvents
     The main technically and economically feasible alternative to cold
cleaning with trichloroethylene, perch!oroethylene, methylene chloride,
1,1,1-trichloroethane, trichlorotrifluoroethane, or carbon tetrachloride
is  cold cleaning with other solvents, such as mineral spirits.   Of the
six halogenated solvents investigated, 1,1,1-trichloroethane is used most
often in cold cleaning operations.  In 1979, it was estimated that 115,000 megagrams
115,000 megagrams (127,000 tons) of 1,1,1-trichloroethane was used in
this manner (see Table 2-2).
     By converting to other organic solvents, no capital  charges would be
incurred.  In addition, actual operating costs could be reduced because
of  the lower price and evaporative rates of other solvents.   Emissions
from a typical cold cleaning operation would be reduced from 740 kg/yr
to  100 kg/yr by converting from 1,1,1-trichloroethane to  mineral spirits.  This
would result in an annual  savings of $450 per unit.
     An alternative to converting to other organic solvents  is  to use
aqueous cleaning systems in the same dip tank as the halogenated solvents.
Although design requirements on some units may prohibit such conversion,
many cold cleaner manufacturers make units which can use  either solvent or
aqueous systems.  One such manufacturer is Economics Laboratory, Incorporated.
In addition to solvent cleaning, Economics Laboratory's machines are used
for alkaline cleaning, derusting,  stripping, and phosphatizing.45
     By converting from 1 ,1,1-trichloroethane to an aqueous  solution,
additional  costs of approximately $1,100 per year could be incurred  for an
average size cold cleaner.  This cost is based on chemical  cost and
solution lifetime with no  additional  equipment costs to implement substitution.
This is a worst case situation, assuming that the aqueous solution is
replaced every 20 work days.3   In  a year's time, 5,300 liters of solution,
worth $1,580 would be consumed.  In the same time frame,  740 kg of halogenated
solvent would be consumed, worth $500.   If the aqueous solution was
replaced once every 9 months,  only $160 worth of solution would be consumed,
saving $340.
 Replacement of aqueous  solutions range from 20 days  to  9  months.
                                    2-43

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2.4.3.2  Vapor  Degreasing and Alternatives

•     Vapor degreasing versus alkaline washing—Several studies comparing the
      cost of vapor degreasing to alkaline washing have been completed in the
      past ten years.  In one study, Eureka Laboratories,  Incorporated,
      building upon earlier work done by the American Society for Metals
      (ASM), compared an open top vapor degreaser to an alkaline washer.
      Each system cleaned 100 pound steel cabinets at the  rate of 100 per
      hour.  A comparison of costs between the two systems is presented in
      Table 2-8.

      Table 2-8  shows that capital and operating costs were higher for the
      alkaline washer.  The annualized capital cost for the alkaline washer
      was $17,330, almost twice the annualized capital cost of $9,140 for
      the vapor  degreaser.  The cost difference is attributed to higher
      equipment  costs and greater building space requirements for the
      alkaline washing systems.  The annual operating costs for vapor
      degreaisng were $54,780 while the annual operating costs for the
      alkaline washer were $72,220.  The greater annual operating costs for
      the alkaline system can be attributed primarily to the cost of
      utilities, such as gas for heating water and air, and the cost for
      rejects handling.  The cost for rejects handling represents a product
      quality cost.  When the total annualized costs for the two systems are
      compared,  alkaline washing was shown in this test to be about 40 percent
      more costly than vapor degreasing.

•     Conveyorized vapor deqreasing versus alkaline washing—Another study,
      performed  by Dow Chemical  Company at a General  Motors plant in Grand
      Rapids, Michigan, compared a vibra degreaser (a type conveyorized
      vapor degreaser) to a spiral alkaline washer.   The results of this
      study, cited by Eureka Laboratories, Incorporated are presented in
      Table 2-9.   In the test, diesel  equipment parts were cleaned by each
      system.  The annualized capital  costs for the vapor degreaser are
      $10,080, or about 35 percent higher than the annualized capital  costs
      of $6,460  for the spiral  washer.   This difference in annualized
      capital  costs is due primarily to the higher equipment cost for the
      vapor degreaser.  The annual operating costs for alkaline washing are
      $26,360, about 32 percent higher  than the annual  operating costs of
      $19,910 for the vapor degreaser.   The difference in annual  operating
      costs is due primarily to greater material  and  steam costs per year
      for the alkaline washing system.   The total  annualized costs (the sum
      of annualized capital  charges and annual  operating costs)  for
      conveyorized vapor degreasings  are $29,990,  about 12.5 percent less
      than the total  annualized costs of $33,820  for  alkaline washing.

•     Vapor deqreaser versus  alkaline washing—Results  of tests  comparing
     vapor degreasing and alkaline washing were  reported  by Hamilton  Standard
      to EPA's Effluent Guidelines Division in  1979.   The  analysis was
     normalized  on a cost per thousand square  foot  basis.   The  tests  show
      that alkaline washing  requires  a  71  percent  greater  capital  outlay for
     equipment and related  items  than  the vapor  degreaser.  In  the  vapor
     degreasing  system,  solvent  costs  accounted  for  86  percent  of the
                                  2-44

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TABLE 2-8.   COMPARISON OF COSTS FOR VAPOR DECREASING
            AND ALKALINE WASHING ($)58
Item
Capital costs
Equipment
Installation
Building space
50% indirect
Insurance
Operating costs
Direct labor
Material
Utilities
Water
Steam
Electricity
Gas
Maintenance
Labor
Parts
Rejects handling
Overhead
Total annual i zed cost
Vapor
degreasing
Absolute Annual ized
52,800
7,900
60,700 7,130
4,920
2,460
7,380 810
1,200
9,140

17,500
22,740

50
4,170
160
--

3,500
1,410
--
5,250
54,780
63,920
Alkaline
washing
Absolute Annual ized
70,400
10,600
81,000 9,520
32,800
16,400
49,200 5,420
2,390
17,330

17,500
7,580

--
--
1,120
24,000

5,000
2,000
9,390
5,630
72,220
89,550
                        2-45

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                TABLE 2-9.  COMPARISON OF COSTS  FOR  CONVEYORIZED
                            DECREASING AND ALKALINE  WASHING  (S)59
Conveyorized Alkaline
degreasing washing
Capital costs
Equipment
Instal lation
Building space
50% indirect
Annual capital charges
Equipment & installation
Building space
Insurance
Annual operating costs
Maintenance (labor, parts)
Material
Steam
Water
Wastewater treatment
Electricity
Make-up air heat
Residue disposal
Total annual cost
Cost/metric ton of metal cleaned

62,380
9,360
2,090
1,040

8,430
340
1,310


5,980
6,780
4,770
590
0
570
0
1,220



42,920
6,440
4,130
2,070

5,800
680
980
10,080

4,000a
9,230
11,780
13
58
950
330
0
19,910
29,990
6.00








7,460








26,360
33,820
6.76
aAssume $2,380/year as the cost for parts.
                                    2-46

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operating costs.  This was counterbalanced by the higher energy costs
with the alkaline system such that total operating costs varied by
less than 2 percent.  This indicates relative parity between the
two systems.

Comparison of Hamilton Standard Data and Dow Chemical Data—The Hamilton
Standard data and the Dow Chemical data are presented for comparison in
Table 2-10.  The data are normalized on a cost per thousand square foot
basis.  The capital charges in the Dow study are $5.08 for vapor degreasing
and $5.78 for alkaline cleaning.  These costs show that capital charges
for alkaline cleaning are about 14 percent higher than vapor degreasing
costs.  The Hamilton Standard data show the capital  charges for vapor
degreasing as $2.34 and for alkaline cleaning as $4.01.  This study
shows that the capital charges for alkaline washing  are about 71 percent
greater than for vapor degreasing.  The difference in capital charges
for vapor degreasing and alkaline washing between the two studies is
attributed to a greater difference in equipment costs for vapor degreasing
and alkaline washing in the Hamilton Standard study  than the Dow Chemical
study.

The operating costs in the Dow study are $13.11  per  thousand square
feet for vapor degreasing and $14.91  for alkaline washing.   These costs
again show that operating costs for alkaline washing are about 14 percent
greater than operating costs for vapor degreasing.  In the  Hamilton
standard study, the operating costs are $11.04 for vapor degreasing and
$11.26 for alkaline washing.  These data show that operating costs for
alkaline washing are about 2 percent greater than the operating costs
for vapor degreasing.

The Dow Chemical data show total  costs of $18.19 for vapor  degreasing
and $20.69 for alkaline washing.   These data show that alkaline washing
costs $2.50 more per thousand square feet than vapor degreasing, or
about 14 percent more than vapor degreasing.  The Hamilton  Standard
data show total  costs of $13.38 for vapor degreasing and $15.27 for
alkaline washing, a difference of $1.89 per thousand square feet per
year.  These data indicate total  costs for alkaline  washing are about
14 percent greater than the total  costs for vapor degreasing.

Both the Dow and the Hamilton Standard studies conclude that the total
cost for alkaline washing is about 14 percent greater than  the total
cost for vapor degreasing.   The Hamilton Standard study, however,
attributes most of the total  difference in cost  to a greater difference
in equipment costs between vapor degreasing and  alkaline washing than
the Dow Study.

Vapor Degreasing versus Emulsion  Cleaning—Eureka Laboratories, Incorporated,
compiled comparative cost data for vapor degreasing  and emulsion cleaning
from a test in which both processes were used to clean aluminum alloy
reflectors weighing four pounds each.  Table 2-11  presents  the results
of the tests.
                              2-47

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TABLE 2-10.
COST COMPARISON BASED ON ACTUAL DATA:
VERSUS ALKALINE WASHING60

       (Cost  per thousand square feet)
VAPOR DECREASING

Equipment
Building
Insurance
Maintenance
Chemicals
Steam
Electric power
Water
Waste treatment
Make-up air heat
TOTALS
Dow Chemi
Vapor
degreaser
4.26
0.16
0.66
5.08
5.08
4.32
2.68
0.49
0.54
Neg.
--
13.11
18.19
cal data
Al kal ine
cleaner
4.53
0.49
0.76
5.78
0.66
6.61
5.63
1.31
Neg.
0.54
0.16
14.91
20.69
Hamilton Standard
Vapor
degreaser
1.96
0.06
0.32
2.34
0.90
9.49
0.60
0.05
Neg.
Neg.
—
11.04
13.38
data
Alkal ine
cleaner
3.28
0.21
0.52

1.22
3.93
5.13
0.55
0.14
0.15
0.14



4.01






11.26
15.27
                                2-48

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TABLE 2-11.   COMPARISON OF COSTS FOR VAPOR DECREASING
             AND EMULSION CLEANING ($)61
Item
Capital costs
Equipment
Installation
Building space
50% indirect
Insurance
Operating costs
Direct labor
Material
Utilities
Water
Steam
Electricity
Gas
Maintenance
Labor
Parts
Rejects handling
Overhead
Total annual ized cost
Vapor
degreasing
Absolute Annual ized
32,300
4,840
37,140 4,360
3,280
1,640
4,920 540
740
5,640

17,500
11,340

30
1,490
160
--

2,000
1,160
--
4,880
38,560
44,200
Emu! si on
cleaning
Absolute Annual ized
49,900
7,480
57,380 6,740
13,670
6,830
20,500 2,100
1,410
10,250

17,500
4,250

--
--
670
8,800

2,000
2,320
3,010
4,880
43,430
53,680
                       2-49

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      Annualized capital  charges  are $5,640  for vapor  degreasing  and  $10,250
      for emulsion  cleaning.   The annualized capital charges  for  emulsion
      cleaning are  about  82  percent greater  than the annualized capital
      charges  for vapor degreasing.  This  difference is  attributable
      primarily to  greater costs  for equipment  and  building space  for  the
      emulsion cleaning system.

      Annual operating costs  are  $38,560 for vapor  degreasing and  $43,430 for
      emulsion cleaning,  representing about  a 12 percent difference in cost.
      The vapor degreasing operation shows a $7,090 greater annual cost for
      materials than emulsion cleaning.  However, emulsion cleaning shows an
      annual cost of $8,800  for gas for heating  and an annual cost of  $3,010
      for rejects handling while  vapor degreasing shows no cost for either of
      these  items.

 •     Vapor  Degreasinq with Trichlorofluoromethane  (CFC-11)--CFC-ll is a
      technical  substitute for trichloroethylene, 1,1,1-trichloroethane,
      methylene chloride, and trichlorotrifluoroethane in vapor degreasing.
      However,  the  use of CFC-11  historically has been restricted to a few
      specialized cold cleaning operations.  Two reasons for its limited use
      are  its  high  volatility and  its  potential  to  deplete stratospheric
      ozone.

      Using CFC-11  in vapor degreasing requires  retrofitting an existing
      degreaser with a refrigerated  freeboard device to prevent excessive
      solvent  losses.  A capital outlay ranging  from $6,200 to $13,000 (depending
      upon the  size of the degreaser) would  be required to install this
      device.61   The impact on annualized costs would vary depending
      on the solvent which CFC-11   replaces.  While  the use of a refrigerated
      freeboard device would  reduce  total  solvent emissions, variations in
      solvent  price ($0.60/kg for  trichloroethylene to $1.04/kg for CFC-11)
      prohibit  the  inference  that  net annualized operating costs would be
      less with CFC-11.

      In conclusion, CFC-11  can be viewed as a technically feasible substitute.
      Data is  insufficient to completely assess its economic feasibility,  but
      evidence  suggests there are   instances where the capital  outlay associated
     with its  use can be offset by a net solvent savings.  This  would  occur
      ,vhen the  recovered  value of  the solvent is greater than  the  cost of the
     emission control.  However,  due to the ozone depletion question,
     environmental  regulatory policy may be the most salient  factor
     affecting the  use of CFC-11  as a substitute.

2.5  CONCLUSIONS AND RECOMMENDATIONS

     Due to the diversity of the  process  variables, alternatives  to the

use of these solvents  may not exist in every cleaning  operation and the

choice among relatively  comparable cleaning  methods will  not  always be

predicated on  economic grounds.   There is  strong evidence  indicating  that
                                   2-50

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in many industrial processes metal cleaning is not designated as a cost
center for accounting purposes.  Metal cleaning is often included in the
"overhead" category such that a significant number of users of solvent
metal cleaning in all industries do not tend to regard cleaning expenditures
as critical investment decisions.  Given these factors, the large-scale
economic impacts arising from substitution are difficult to ascertain.
     However, the data presented in this analysis provide certain insights
into the technical and economic feasibility of solvent substitutes for
metal cleaning.  First, cost and effectiveness comparisons continue to be
performed, especially between vapor degreasing and alternative systems.
These tests indicate interchangeability between these is often feasible.
This is also underscored by the view of solvent and aqueous cleaning
equipment manufacturers that they are competing in the same industrial
markets.  Second, research and development by both aqueous washing and
cleaning compound manufacturers has increased steadily.  The goal  is to
provide aqueous cleaning systems to industry that are functionally equivalent
and cost competitive to solvent-based systems.  This trend is important
because the comparative cost data presented in the economic analyses
indicate that higher energy consumption is the primary reason why aqueous
cleaning systems demonstrate higher operating costs than vapor degreasers.
Recognizing that reductions in the energy consumption of aqueous cleaning
equipment can close the cost gap between these systems, several  major
manufacturers of aqueous cleaning chemicals have formulated compounds
capable of achieving a high level of cleaning efficiency at substantially
lower operating temperatures than have previously been employed (83°C
                            ?7 fi?
down to approximately 20°C).  '    Further technological  refinements on
the part of aqueous washer manufacturers is acting to close the cost gap
between aqueous and solvent cleaning systems.  For example, one major
manufacture of aqueous cleaning equipment reports development of "closed-loop"
alkaline washing systems which will reduce energy consumption, substantially
reduce effluent and effluent treatment cost, and provide a resource
recovery mechanism which will  reduce the time required for capital  recovery.
                                   2-51

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     Data from comparative studies between cold solvent and  vapor  degreasing
systems and alternative systems have shown solvent systems historically
to be less costly to operate.   However, in most applications  there is
relative parity in the degree  of cleaning effectiveness.  Additionally,
evidence shows that the trend  is toward greater capital  and  operating
parity, at least between vapor degreasing and aqueous  cleaning  systems.
Technological  innovations, particulary in the area of  reduced energy
consumption may play a major role in increasing both the  technical  and
economic feasibility of using  substitutes for solvents in metal  cleaning.
     Generalizations concerning industry-wide ability  to  implement alternative
cleaning methods for those using halogenated solvents  are complicated by
limited and often dated information.  In order to determine  more fully if
substitution of the alternative methods examined in this  analysis
represent viable choices for the majority of solvent users,  research is
needed to supplement existing  data in a number of areas.  The results of
this research  can be used to develop model  cost data based on engineering
and accounting analyses for the purpose of estimating  the approximate
costs of substitution for a selected cross-section of  different  type and
size solvent users; identify historic trends in the use of alternative
cleaning methods in relation to solvent cleaning; determine  the  market
structure of and for solvent substitutes; investigate  the extent to which
capital budgeting decisions of solvent users are affected by  the availability
of substitute  cleaning methods and uncertainties in the regulatory environment
regarding solvents; calculate  any added costs to consumers;  and  estimate
the impacts on solvent producers under varying levels  of  substitute
usage.
                                   2-52

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 2.6   REFERENCES


  1.   U.S. Environmental Protection Agency.  Materials Balance Summaries
      for Trichloroethylene, Perchloroethylene, 1,1,1-Trichloroethane,
      Methylene Chloride, and Trichlorotrifluoroethane.  Office of Toxics
      Integration.  Washington, DC.  August 1981.

  2.   U.S. Environmental Protection Agency.  Organic Solvent Cleaners -
      Background Information for Proposed Standards (EPA-450/2-78-nd5a)
      Office of Air Quality Planning and Standards.  Research Triangle
      Park, NC.  October 1979.  p. 8-23.  (growth factors applied to
      estimate 1980 levels).

  3.   Personal Communication.  Terry O'Brian, GCA Corporation with J. Otrhalec,
      Detrex Chemical  Industries, Detroit, MI.  September 22, 1981.

  4.   Springs, S.   Cleaning and Detergency.  Metal  Finishing.  November 1974.
      p. 59.

  5.   Spencer, L.F.  The Cleaning of Metals:   Part  1-Alkaline Cleaning.
      Metal  Finishing.  April 1962.  p. 59-60.

  6.   ASM Committee on Selection of Cleaning  Processes.  Selection of
      Cleaning Processes, Metals Handbook.  The American  Society for
      Metals, Cleveland, Ohio.  Vol. 2, p. 307.

  7.   Leung, S. et al.  Alternatives to Organic Solvent Degreasing.
      Eureka Laboratories,  Incorporated.  Sacramento,  California.   May 1978.
      pg. 75.

 8.   Reference 5, pps.  60-61.

 9.  Springer, S.   Chemical  Used in Industrial  Cleaning.   Metal  Finishing
     December 1974.   p. 36.

10.  Personal  Communication.  Terry O'Brian,  GCA Corporation with
     Dennis  Willis, Economics Laboratory, Incorporated,  St.  Paul, MN.
     December 29,  1981 .

11.  Letter and attachments  from Westray, W.K,  to  U.S. Environmental
     Protection Agency, Central  Docket Section,  Docket No  OAQPS-78-12.
     October 24,  1980.  pg.  6.   Comments on Proposed Standards  of  Performance
     for Organic  Solvent Cleaners.
                                   2-53

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 12.   Kleer-Flo Parts  Washer and  Cleaning  Solution  Catalogue.   Kleer-Flo
      Company,  Eden  Prairie, Minnesota.  March  1980.   p.  1-12.

 13.   Surprenant,  K.S.  and  D.W. Richards,  Study to  Support New  Source
      Performance  Standards  for Solvent Metal Cleaning Operations.  U.S.
      Environmental  Protection Agency, Office of Air Quality Planning and
      Standards, Research Triangle  Park, North  Carolina.  EPA Contract
      Number 68-02-1329, Task Order Number 9, June  30, 1976.  p. 17.

 14.   Personal  Communication.  Terry O'Brian, GCA Corporation with Graham
      Pendleton, Kleer-Flo Company,  Eden Prairie, MN.  November 2, 1981.

 15.   Personal  Communication.  Terry O'Brian, GCA Corporation with Dennis Willis,
      Economics Laboratory,  Incorporated, St. Paul, MN,  November 9, 1981.

 16.   Personal  Communication.  Terry O'Brian, GCA Corporation with
      Lyle Carmen, Ransohoff Corporation, Hamilton, OH.  November 13, 1981.

 17.   Briggs, J.L. et al..  A Comparative Study  of Aqueous and Solvent
      Methods for  Cleaning Metals.   U.S. Energy  Research and Development
      Administration, Albuquerque Operations Office, Albuquerque, New
      Mexico.   ERDA  Contract Number  E(29-2)-3533, April 1976.

 18.   Personal Communication.  Terry O'Brian, GCA Corporation with Jim Dingman,
      Pack Industries,  Incorporated, Greensboro, NC.  November 16, 1981.

 19.   Letter from Art Gillman, Unique Industries, Inc.   Sun  Valley,  CA to
      Richard Rehm,  GCA/Technology Division.   February 8, 1983.

 20.   Wagner, L.K.   Organic Surface Contimination - Its Identification,
      Characterization, Removal,  Effects on Insulation  Resistance and
      Conformal  Coatings Adhesion.   Institute for Interconnecting and
      Packaging Electronic Circuits.  Evanston,  IL.   September 1981.

 21.   Personal Communication.  Terry O'Brian, GCA Corporation with Steve Temple,
      Ransohoff Incorporated, Hamilton,  OH.  November 5,  1981.

 22.   Personal Communication.  Terry O'Brian, GCA Corporation with Paul  Salz,
      Unique Industries, Incorporated,  Sun  Valley,  CA.   December 12,  1981.

 23.   Personal Communication, Terry O'Brian,  GCA Corporation  with  Frank  Barr,
     Graymills  Incorporated, Chicago,  IL.   November 2,  1981.

 24.  Personal Communication.  Terry O'Brian, GCA Corporation with Lyle  Carmen,
     Ransohoff  Incorporated, Hamilton,  OH.   November 17,  1981.

25.  Personal  Communication.  Terry O'Brian, GCA Corporation, with Grady  Rorie,
     General Motors  Corporation,  Warren, MI. November 30, 1981.

26.  Reference  13, p.  4-29.
                                   2-54

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  27.   Personal Communication.  Terry O'Brian, GCA Corporation with John Sparks
       DuBois Chemical Company, Cincinnati, OH.  November 18, 1981.

  28.   Personal Communication.  Terry O'Brian, GCA Corporation with Lyle Carmen
       Ransohoff Incorporated, Hamilton, OH.  April 22, 1982.

  29.   Personal Communication.  Terry O'Brian, GCA Corporation with Graham Pendleton
       Kleer-Flo Company, Eden Prairie, MM.  April  22, 1982.

  30.   Personal Communication.  Terry O'Brian, GCA Corporation with Dennis Willis
       Economics Laboratory, Incorporated, St. Paul,  MM.   April  22, 1982.

  31.   Spencer, L.F.  The Cleaning of Metals:   Part 3-Emulsion and  Diphase
       Cleaning.  Metal  Finishing,  June 1963.  p.  85.

 32.   Reference 7, p. 92.

 33.   Connolly, J.T.   Metal  Cleaning with Emulsions  - An  Update.   Journal  of
      the Society  of  Lubrication  Engineers.   December 1976.   pps.  651-654.

 34.  Graymills Parts Washer and  Cleaning Solution Catalogue Number GM  65R-6
      Graymills Corporation, Chicago,  Illinois.  May  1978.   p.  1-16.

 35.  Glover,  H.C. Are  Emulsified  Solvents Safer  Cleaners?   Production
      Engineering. July 1978.  p.  41-43.

 36.  Reference 33, p. 651.

 37.  Reference 33, p.   "53.

 38.  Metal  Finishing and Surface Preparation.  Equipment specification sheet
      Number 513-56.  Inland Manufacturing Company, Omaha, Nebraska.  June 1977.

 39.   Lyman, T   ed., Blast  Cleaning of Metals.  Metals Handbook.  The American
      Society for  Metals, Cleveland, Ohio, 1948.  p.  300-301.

 40.   Personal  Communication.  Terry O'Brian,  GCA Corporation with  Peter Hoezel ,
      Inland Manufacturing Company, Omaha, NB.  December 11, 1981.

 41.   Handbook  of  Industrial Blasting:  Section 1  - Automotive Parts Cleaning
      Inland Manufacturing Company, Omaha, Nebraska.   1972.   p.  1-9.
42-  P^SOf]al Interview-  Terry O'Brian, GCA Corporation with Hank  Osterman,
     Allied Corporation, Morristown, NJ.  October 28,  1981.

43.  Physical Properties of Common Organic Solvents  and Chemicals.   Chemcentral
     Corporation.  Chicago, Illinois.   1980.   ps.  1-4.

44.  Chemical Marketing Reporter,  Schnell  Publishing Company,  New York,  NY,
     March 31,1 981 .
                                   2-55

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 45.  Mangus Cleaning and Processing Equipment Catalouge.   Economics
      Laboratory, Incorporated, St. Paul, Minnesota.   1979.   p.  5.

 46.  Reference 43, p.  3.

 47.  Tang, J.L.  Industrial  Survey of Halogenated Solvent Producers  and
      Degreaser Manufacturers.   GCA/Technology Division.   July  1981.

 48.  Personal  Communication.   Terry O'Brian,  GCA Corporation with
      Hank Osterman,  Allied Corporation,  Morristown,  NJ.   December 30,  1981.

 49.  Personal  Communication.   Samuel  Duletsky,  GCA Corporation with
      Jim Watson, Getty Refining and Marketing Company, Tulsa, OK.
      November  4, 1981.

 50.  Personal  Communication.   Terry O'Brian,  GCA Corporation with
      Burton Rand,  AutoSonics,  Incorporated, Norristown, PA.  June 13,  1981.

 51 .  Reference 7,  p. 90.

 52.  O'Brian,  T.   Estimation of Market Share  of  Metal Cleaning Techniques,
      GCA/Technology  Division,  Chapel  Hill, North  Carolina.  December 1981.

 53.  U.S.  Environmental  Protection  Agency.  Control of Volatile Organic
      Emissions  from  Solvent Metal  Cleaning, EPA-450/2-77-022.  Office of
      Air Quality Planning  and  Standards, Research  Triangle Park, North
      Carolina.   November 1977.   p.  2-5.

 54.   Reference  2,  pps. 8-17 and  8-23.

 55.   Letter  from Ted Mueller,  Safety-Kleen Corporation, to Richard Rehm,
      GCA/Technology  Division,  October, 1980.

 56.   Graymills  Equipment Price  List Number GMPL-20.  Graymills  Corporation
      Chicago,  Illinois, April  1981.  pp.  1-4.

 57.   Erickson,  P.R. and W.M. Throop.  Improved Washing of Machined Parts.
      Production  Engineering.  March 1977.  pp. 55-57.

 58.   Reference  7, p. 146.

 59.   Reference  7, p. 157.

 60.  Bauks, S.V. and K.J. Dresser.  Cleaning Alternative  to  Organic Solvent
     Degreasing.  Technical report prepared for the U.S.  Environmental
     Protection Agency, Effluents Guideline Division,  Washington,  D.C.
     December 1979.  pp.  1-12.

61 .  Reference 11,  p. 149.

62.  Personal Communication.   Terry O'Brian, GCA Corporation with  Dennis
     Forian, Oakite Products,  Incorporated, Berkeley  Heights, NJ.
     November 19, 1981.

                                   2-56

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                         3.0  DRY CLEANING INDUSTRY

3.1  GENERAL DESCRIPTION OF USE
3.1.1  Process Description
     Dry cleaning is a process in which organic solvents, rather than
detergent and water, are used to clean clothing and other articles.   The
principal steps in the process are identical  to those of laundering  in
water.  In the first step, clothes are loaded into the washer and solvent
is added.  The clothes and solvent are then agitated by the turning
motion of a paddle or wheel.  After washing is completed, the clothes are
spun as in a conventional washer spin cycle to extract the solvent.
After extraction, the used solvent is filtered and distilled to remove
impurities and is then returned to the system.  After solvent wash and
extraction, the clothes are tumbled dry.   During the drying cycle, the
evaporated solvent is either recovered in a condenser and returned to the
system or vented to the atmosphere.  Solvent  remaining in the clothes is
reduced by venting ambient air through the clothes.   This last process is
referred to as aeration or deodorization.
     There are two basic types of dry cleaning machines:   transfer
machines and dry-to-dry machines.  Transfer machines are  those in which
washing and drying are performed in different machines.   After washing
and extraction, the fabrics are transferred to the dryer.  Dry-to-dry
machines are those in which washing and drying occur in  a single unit.
     Three solvent types are used in the  dry  cleaning industry:
perchloroethylene (perc), trichlorotrifluoroethane (CFC-113) and petroleum
solvents.  Of these three solvents, perchloroethylene is  preferred by
most users.  Perchloroethylene is nonflammable,  has  excellent solvent
properties, does not damage apparel, can  be used in  transfer machines and
dry-to-dry machines, and is comparable to petroleum  solvents on  a
performance or production basis.   Because of  its high cost CFC-113 is
                                   3-1

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used only by a small percentage of dry cleaners.  However, its nonflammability,
rapid low temperature drying characteristics, gentle solvent properties,
and low toxicity make CFC-113 an alternative to perch!oroethylene and
petroleum solvents.
     About 30 percent of the total quantity of clothes cleaned by the dry
cleaning industry are cleaned using petroleum solvents.  Petroleum solvents
are mixtures of paraffins and aromatic hydrocarbons that are similar to
kerosene.  In the past, petroleum solvents were much less expensive than
perchloroethylene.  However, at present, petroleum solvents and perc are
priced competitively.  A recent trend has been to substitute to perc for
petroleum solvents.  Table 3-1  lists the physical  properties of several
types of petroleum solvents used in dry cleaning.
     The machines and operating procedures used in dry cleaning vary with
the type of dry cleaning solvent used.  Petroleum solvents are combustible
while halogenated solvents, perc and CFC-113, are  nonflammable.  Therefore,
petroleum solvent machines are  specially designed  to be explosion-proof,
while perc and CFC-113 machines require no such special  design.  All
petroleum solvent dry cleaners  use transfer type machines to reduce the
risk of fire and explosion.  Perc can be used in either transfer machines
or dry-to-dry machines.   Machines using CFC-113 are all  of the dry-to-
dry type.  Machines used to dry articles washed in perc or CFC-113 are
usually equipped with a  condenser and a carbon  adsorber to capture vapors
as they leave the dryer.  Petroleum dryers typically vent the volatilized
solvent stream directly  to the  atmosphere without  any type of solvent
recovery.  However, petroleum dryers fitted with condensers to remove
petroleum solvent from the dryer exhaust are currently manufactured and
sold in the United States.   This type of dryer  is  called a recovery
dryer.    A schematic of  a  perc  dry cleaning plant  is shown in Figure  3-1.
A typical  petroleum solvent dry cleaning plant  is  shown  in Figure  3-2.
 Because of these characteristics,  DuPont  stated  that CFC-113  should  not
be equated with perchloroethylene in  this  analysis  (see Appendix  A)
                                   3-2

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                    TABLE 3-1.  PHYSICAL PROPERTIES OF  PETROLEUM  DRY  CLEANING  SOLVENTS'
OJ
I
OJ
Chevron
Property
Flash point (°F)
Initial BP (°F)
Dry end point (°F)
Specific gravity 0 GOT
Heat of vaporization (Btu/lb)
Average molecular weight
TLV (ppm)
Aromatics content (%V)
Naphthenes content (%V)
Paraffins content (XV)
325
101
316
366
0.784
119
138
250
2
67
31
450
146
363
477
0.809
108
166
275
2
62
36
Shell
Mineral
spirits
140
113
332
392
0.786
-
-
-
12
44
44
AMSCO
Mineral
spirits
105
312
390
0.786
-
-
-
17
36
47
Ashland
Kwik Dri
103
315
360
0.750
104
130
500
3
35
62
Inland Oil
Stoddard
108
324
390
0.784
-
_
200
12
44
44
140-F
143
364
399
0.784
_
_
175
9.5
45
45
          denotes data  unavailable.

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                                                             EXHAUST GAS/SOLVENT
CO
I
                              DETERGENT
MUCK


GASES

SOLVENT


EMISSIONS
                                                                     HEATED AIR
                                                              FILTERED
                                                              SOLVENT
                                               DISTILLATION

                                                 BOTTOMS
                                                 SOLVENT
SEPARATOR


CONDENSER
                        Figure 3-1.   Perchloroethylene  dry  cleaning plant  flow diagram.'

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                           SPENT SOLVENT
                                           -»
                                       FILTER
NEW SOLVENT IN
                                                FILTERED SOLVENT
                                   FILTER WASTE
                                   TO DISPOSAL
         FILTER WASTE
      SOLVENT REMOVER
VENT     OR CENTRIFUGE
                                                FILTER
                                                WASTE
               NEW AND
              REGENERATED
               SOLVENT
              STORAGE TANK
                              DISTILLED SOLVENT
                                     X
                                                                       VENT
                                                                FILTERED
                                                                 SOLVENT
                                                                  TANK
                                                     CONDENSER
                                                         BOILING
                                                         CHAMBER
                                             SOLVENT  I
                                             VACUUM   '	^
                                              STILL    STILL WASTE
                                                      TO DISPOSAL
                     LEGEND

                       SOLVENT FLOW

                       VAPOR EMISSION

                       SOLID WASTE EMISSION
                                        o
                                                                DRYER
      Figure 3-2.  Petroleum solvent dry cleaning plant flow diagram.
                                       3-5

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3.1.2  Industry Characterization
     The dry cleaning industry is subdivided according to  the  type  of
solvent used and the type of services offered.   As  previously  mentioned,
three solvent types are used in the dry cleaning industry:   petroleum
solvents, perc, and CFC-113.  The industry is also  composed  of three
sectors which are delineated by the type of services  offered:   the  self-service
or coin-operated sector; the commercial dry cleaning  sector; and  the
industrial dry cleaning sector.   Coin-operated dry cleaning facilities
are usually, but not necessarily, part of a "laundromat"  facility and
operate either on an independent or franchise basis.   Commercial  dry
cleaning plants are the most familiar type of facilities,  offering  the
normal  services of cleaning soiled apparel or other goods.   They  include
small neighborhood dry cleaning shops operating on  an independent basis,
franchise dry cleaning shops, and speciality cleaners which  handle  leather
and other fine fabrics.  The largest dry cleaning plants  and cater  to
industrial, professional, and institutional customers. Articles  such as
mats, mops, rugs, and work uniforms are cleaned by  industrial  dry cleaners,
often in conjunction with rental operations.  The estimated  percentage of
dry cleaning operations using solvents in each  of the three  categories in
which the industry can be segregated is shown in Table 3-2.

     TABLE 3-2.  ESTIMATED NUMBERS OF DRY CLEANING  OPERATIONS  AND SOLVENT
                 USAGE IN THE UNITED STATES1'7'8'9
Type of
operation
Coin-operated
Commercial
Industrial
Number of
operations
11,800-18,000
25,000
920- 1 ,000
Percent using
perchloroethylene
97.5
73
75
Percent using
CFC-113
2.5
3
0
Percent using
petroleum
solvents
0
24
25
                                   3-6

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       As  shown in  Table  3-2,  all  coin-operated  dry  cleaning  operations  use
  either perc or CFC-113.   The use of  petroleum  solvents  by coin-operated or
  self-service dry  cleaning  plants is  prohibited by  National  Fire  Protection
  codes  due  to the  highly volatile and  flammable nature of petroleum solvents.10
       Table 3-2 also shows  that 75  percent of industrial dry cleaning
  establishments use perc and  25 percent use petroleum solvents.   This may be
  misleading however, since  50  percent  of the total weight of clothes dry
  cleaned  by industrial plants  are cleaned with  perc and 50 percent with
  petroleum  solvents.  The industrial dry cleaners that use petroleum solvents
  generally  have  larger machines than those which use perc, thus allowing them
  to clean more  clothes per plant per year.
      In  1979,  211,000 megagrams (233,000 tons)  of perch!oroethylene and
  1,670 megagrams (1,850 tons)  of CFC-113 were used in the dry cleaning
  industry.    About 136,000 megagrams  (150,000 tons) of petroleum solvents
 were used.
 3.2  DISCUSSION OF SUBSTITUTES
      For an organic  solvent to be acceptable  as a dry  cleaning solvent, the
 solvent should possess the  following  properties:  the  solvent  must  neither
 weaken nor  shrink  ordinary  textile  fibers; the  solvent must  not  bleed common
 dyes  from such fibers; it must have the ability to  remove fats  and oils; it
 should  not  impart  objectionable odors  to textiles;  and it should  not be
 corrosive to metals. 3  Petroleum solvents possess  these characteristics to
 the degree  that they can be considered proven dry cleaning agents as
 substitutes for perc and CFC-113.   Several other solvent mixtures possess
 these characteristics to the degree that they can be considered potential  dry
 cleaning  agents.

     At the present time, petroleum solvents account for slightly less  than
 30 percent  of  the annual  national  dry cleaning throughput.  Dry cleaning
 patents have been issued  for tetrachlorodifluoroethane, 1,2,-dichloroethylene,
 hexafluorodichlorobutene, and  quaternary azeotropes  based on  tetrachloro-
 difluoroethane, but these solvents are presently not known to be used  in the
dry cleaning industry.  Representatives of the major dry  cleaning trade
organizations were  contacted to determine  the  extent of use of  these solvents
in the dry cleaning industry,  but  none of  the  representatives claimed any

                                    3-7

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 knowledge  of  the use of these solvents in dry cleaning.    '    Tests
 performed  on  these solvents indicate that they may have some value as dry
 cleaning solvents, but not enough information is available to present a
 detailed analysis of the technical and economic feasibility of using them as
 substitutes for perc and CFC-113.13
     The only solvents for which information about the technical and economic
 feasibility of substitution is readily available are petroleum solvents.
 Petroleum  solvents are the only solvents other than perc and CFC-113 used in
                   14
 dry cleaning  today.    Because perc is used to clean 70 percent of the annual
 national dry  cleaning throughput and CFC-113 is used to clean less than one
 percent, this section addresses the feasibility of substituting petroleum
 solvents for  perc.  The information presented generally applies to the
 substitution of petroleum solvents for CFC-113.
 3.3  TECHNICAL ANALYSIS OF SUBSTITUTES
     This  section analyzes the technical  factors influencing the substitution
 of petroleum solvents for perc in dry cleaning plants.   The factors analyzed
 are the method of substitution,  the impact that fire codes may have on
 substitution, the degree to which petroleum solvents can be substituted for
 perc based on product quality, and the availability of  petroleum solvents and
 petroleum  solvent dry cleaning equipment.
 3.3.1   Method of Substitution
     The only method of substituting petroleum solvent  for perc is to replace
 the perc dry cleaning equipment  with petroleum solvent  dry cleaning equipment.
 This replacement is necessary because petroleum solvents must be used in
machines that are specially designed to be explosion-proof, and perc  machines
are not designed as such.   The major pieces  of equipment that must be replaced
are the washer,  dryer,  solvent still,  and solvent  storage  tank.14
     The replacement of perc  dry cleaning equipment with petroleum dry
cleaning equipment is feasible because  petroleum washers,  dryers,  stills,
and storage tanks  are about the  same size as those  used in perc dry cleaning.
 In addition,  petroleum  washers,  dryers, and  stills  require the  same connections
for electricity  and steam  as  perc  washers,  dryers,  and  stills.
                                  3-8

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3.3.2  Impact of Fire Codes on Substitution
     Although one-for-one equipment replacement is physically feasible,
local fire codes are likely to require extensive remodeling of the building
if petroleum solvents are substituted for perc, and in some cases will not
allow conversion from perc to petroleum solvents.
     Local fire codes for dry cleaning plants are usually based on model
fire codes developed by the National Fire Protection Association (NFPA).
The NFPA classified dry cleaning plants by the type of solvent used.
Solvents, in turn, are classified by their flash points.  Class II and IIIA
solvents are the primary solvents used in the petroleum cleaning industry,
while perc is classified as Class IV.  The NFPA Standard Number 32-1979
dry cleaning solvent classification is as follows:
     •    Class I Solvents - Liquids having a flash point below 38°C (100°F)
          such as 32°C  (90°F) flash  point  naphtha.
     •    Class II Solvents - Liquids having a flash point from 38°C to 59°C
          (100°F to 139°F) such  as quick drying solvents and Stoddard solvents.
     •    Class IIIA Solvents -  Liquids having a flash point ranging from 60°C
          to 93°C (140°F to 199°F) such as 60°C (140°F) "safety" solvent.
     •    Class IV Solvents - Liquids classified as non-flammable, such as
          perc and CFC-113.
     Table 3-3 presents a summary of NFPA requirements for the three types of
dry cleaning plants.   As seen in this table, local  building and fire codes
require different construction for buildings housing perc dry cleaning
operations than for buildings housing petroleum solvent dry cleaning
operations.   These codes affect  existing and new dry cleaning operations.
Local fire codes based on the NFPA Standard would require major changes to
an existing  building  if conversion from perc to petroleum solvents is
attempted.  These changes include:   construction of firewalls and  fire
ceiling;  extensive re-wiring of  the building's electrical  system;  additional
plumbing  for an emergency solvent drainage system;  installation of a sprinkler
system;  installation  of storage  tanks underground;  and installation of a
new building heating  system.   The fire and building codes for a new dry
cleaning  plant could  be met by designing the required  features into the
plant before it is built.

                                     3-9

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                       TABLE  3-3.   SUMMARY  OF MAJOR  NFPA MODEL  FIRE CODE  RECOMMENDATIONS  FOR  THREE TYPES
                                        OF  DRY  CLEANING  PLANTS
                             Type II
           (Using petroleum solvent with flash point at or
                   above IOO°F but below 140"F)
                                                                           Type  IMA
                                                         (Using petroleum solvent with flash point at or
                                                                  above I40"F but below ?00"F)  •
                                                                    Type IV
                                                               (Using nonflammable
                                                                 liquid solvents)
00
 I
•  No other building occupancies



•  Halls of non-combustible construction

•  Emergency solvent drainage system

•  Isolated dry cleaning room


t  Building heated by steam, hot water, or oil only

t  Boiler Isolated in separate room or building

•  Adequate ventilation for dry cleaning room

•  Special hazardous condition wiring

•  Storage of solvent underground, above ground
   outside, or limited storage in dry cleaning room

•  Sprinkler system for entire building
•  If other occupancies, must have sprinkler
   system and two-hour fire partitions
   separating occupancies

«  Walls of non-combustible construction

•  Emergency solvent drainage system

•  Isolated dry cleaning room unless there
   is a sprinkler system

•  Building heated by steam, hot water or oil only

•  Boiler isolated in separate room or building

•  Adequate ventilation for dry cleaning room

•  Wiring for ordinary conditions

•  Storage of solvent underground, above ground
   outside, or limited storage in dry cleaning room

•  Sprinkler system if other occupancies
•  Ventilation adequate to meet TWA's

•  General purpose wiring

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     Because of local  fire codes, the conversion of an existing perc dry
cleaning plant to petroleum solvent may not be feasible for several
reasons.  First, the dry cleaning plant may be located in a leased space,
in which case permission to make extensive changes to the space would have
to be obtained from the building owner.  Dry cleaners often lease space in
shopping centers, and fire codes prevent the use of Class II solvent if
there is an adjoining occupancy.  Second, limitations on floor space or the
building design could preclude the construction necessary to meet the fire
codes.  Third, fire codes may restrict the use of petroleum solvent in
certain areas of a city or even in an entire city.  For example, the cities
of Denver, Colorado and Phoenix, Arizona do not allow new petroleum solvent
dry cleaners to operate within city limits, while New York City does not
allow substitution of flammable for non-flammable solvents in dry cleaning
 i  *  17,18,19
plants.
3.3.3  Degree of Substitution
     The degree to which petroleum solvents can replace perc in dry
cleaning depends in part upon the quality of cleaning done by petroleum
solvents as compared to perc.  The quality of cleaning done by petroleum
solvents is determined by their effect on greases and oils, their ability
to clean articles without damaging them, and their effect on customer
service, such as cleaning time.
     Both perc and petroleum solvents clean apparel  primarily by dissolving
grease and oil which hold soil in the material.  Once the grease or oil is
dissolved, the soil is removed mechanically by the agitation of the
solvent.  Perc dissolves oils and greases more quickly than petroleum
solvent, but generally both solvents are able to clean the most heavily
soiled articles to a comparable degree of cleanliness.    Perch!oroethylene
is a more aggressive solvent than petroleum solvent.   Consequently,  petroleum
solvents are preferred for certain applications such  as leather cleaning
                                                                       20
because petroleum solvent will cause less damage to garments than perc.
                                  3-11

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     The time required to dry clean an article and return  it  to  a  customer
depends on daily throughput, machine capacity, and machine cycle time.
Although most perc machines in use are of the transfer type,  the trend  in
the industry is to manufacture dry-to-dry perc machines because  the  latter
use solvent at a lower rate than transfer machines.  A perc dry-to-dry
machine and a petroleum transfer machine of the same capacity can  clean
apparel at about the same rate.  Although a perc cleaning  cycle  lasts about
half the time of a petroleum wash cycle, the dry-to-dry machine  is also
used to dry the load while articles washed in a petroleum  washer are trans-
ferred to a dryer.  The petroleum washer and dryer can operate continuously
and simultaneously while the perc dry-to-dry machine must  alternately wash
and dry.  Therefore, no loss in customer service due to longer cleaning
time is associated with the use of petroleum solvents.
3.3.4  Resource Availability
     The feasibility of substituting petroleum solvents for perc in  dry
cleaning depends in part upon the availability of petroleum dry  cleaning
equipment, such as washers, recovery dryers, solvent stills,  and storage
tanks, and the availability of petroleum solvents.  Major  manufacturers of
petroleum solvents, petroleum solvent washers, perc washers,  petroleum
dryers, and petroleum solvent stills were contacted to determine the
availability of petroleum solvents and petroleum solvent dry  cleaning
equipment.
     The dry cleaning industry is not a large market for producers of
petroleum solvents.  The dry cleaning industry uses about  151,000  megagrams
                                             21
(167,000 tons) of petroleum solvent per year.    This represents a
relatively small portion of the market for petroleum solvents and  a  very
small portion of the total petroleum liquids market (including gasoline,
heating oils, naphthas, and diesel fuel).  If the demand for  petroleum
solvents in the dry cleaning industry increased to three or four times  the
present level of use, the increased demand would still represent a small
overall increase in demand for petroleum solvents.  The petroleum refining
industry could easily supply petroleum dry cleaning solvents  in  amounts up
                                22 23
to ten times the present demand.  '
                                  3-12

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     The total  number of perch!oroethylene commercial  dry cleaning  plants
operating is estimated to be 18,250.   The total  number of perchloroethylene
industrial dry cleaning plants operating is estimated  to be 750.   Substitution
of petroleum solvent in these plants  involves replacement of perc  washing
machines, dryers, stills, and storage tanks.  All  domestic manufacturers of
petroleum solvent washers were contacted to determine  their capacity to
manufacture petroleum washers.  Companies that manufacture petroleum
washers rely upon the sale of other types of equipment for the majority of
their business because the demand for petroleum washers is very low.
Petroleum washers are built only when a company receives an order  for one.
One company which manufactures industrial washers  (250 pound and 500 pound
sizes) reported that an order for a petroleum washer had not been  received
for two years.     This company estimated that it could produce up  to
100 washers of each size per year if  the demand existed.  Manufacturers of
commercial petroleum washers gave estimates of maximum annual  production
                                                     or or 97
capacity of 180, 400, and 1000 washers, respectively.   ''    The limited
availability of petroleum solvent washers places a constraint upon the rate
at which perc dry cleaners could convert to petroleum  solvents.
     The petroleum sector of the industry is expected  to use solvent recovery
dryers in the future.  The popularity of recovery  dryers is expected to
grow because a large percentage of petroleum solvent,  which is becoming
increasingly expensive, can be recovered in the dryer  and reused.   At
present, only one company in the United States manufactures petroleum
recovery dryers.  The company representative estimated that they have
manufactured and sold about 200 dryers of both 50  and  100 pound sizes.  A
representative of the company stated  that production of the dryers could
                                            28
increase to meet a large increase in  demand.    The availability of recovery
dryers does not appear to be a constraint on the rate  at which petroleum
solvents can be substituted for perc.
     Only one company in the U.S. is  known to manufacture petroleum stills.
Two sizes are manufactured:  a 300 gallon per hour still and a 750 gallon
per hour still.  Approximately 20 of each of these sizes can be produced
         24
per year.    The limited availability of petroleum solvent stills  places a
                                    3-13

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constraint on the rate at which petroleum solvents can be substituted for
perc.  Table 3-4 presents a summary of petroleum solvent equipment manu-
facturers and their annual production capacity.
3.4  ECONOMIC ANALYSIS OF SUBSTITUTES
     This section analyzes the economic feasiblity of substituting
petroleum solvents for perchloroethylene by examining the costs related to
any change in product quality and comparing capital and annualized costs
using perc and petroleum solvents.  An analysis of the ability of dry
cleaners to pay for the costs of substitution is beyond the scope of this
report.
     A model plant approach was chosen to represent the range of plant or
facility sizes currently used for sub-groups of the dry cleaning industry.
Each model plant is constructed using technical parameters representative
of industry production patterns.
3.4.1  Product Quality
     Dry cleaning operations are,  in general, local businesses which are
                                                         pn
fragmented with many small-scale,  independent operations.     Over half of
commercial dry cleaning establishments have fewer than five employees.30
Thus, economic competition is based not only on price, but also on certain
non-price factors such as convenience and dependable product quality.
Three areas where product quality  might be expected to decline in substituting
petroleum solvents for perchloroethylene are:  cleanliness of the article;
timeliness with which it is returned to the customer;  and  absence of
damage resulting from the cleaning process.   There are no  fixed standards
for measuring quality in these areas.   Consumer behavior,  however, is  a
good proxy for judging overall performance.   If the quality of dry cleaning
service significantly declines, consumers will  likely  change their behavior
patterns.  Consumer response could vary from deferred  maintenance of
dry-cleanable articles to more frequent purchases of easy-care clothing and
fabrics.   The result of these or similar actions would impose economic
costs on  dry cleaners.  At a minimum,  dry cleaners would  suffer the cost of
poor reputation.   At a maximum, there would  be  the financial  costs of  lost
revenue which could result in lost profits.

                                   3-14

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    TABLE  3-4.   ESTIMATED  U.S.  PRODUCTION  CAPACITY  FOR  PETROLEUM SOLVENT
                DRY  CLEANING  EQUIPMENT
        Type of
     equipment and
     manufacturer
     Estimated
production capacity
   (units/year)
Washers

  Four State Machinery
    Joplin, MO

  Marvel Manufacturing Co.
    San Antonio, TX

  VIC Manufacturing
    Minneapolis, MN

  Washex Manufacturing Co.
    Wichita Falls, TX
       ,000a


        180b


        400C


        200d
Recovery Dryers

  Hoyt Manufacturing Corp.
    Westport, MA
     >2,400{
Solvent Stills

  Washex Manufacturing Co.
    Wichita Falls, TX
         40C
 Reference 27.

Reference 25.

cReference 26.

 Reference 24.

eAlthough estimate appears high, Hoyt stated that they could produce more
 than 200 units per month.  Reference 28.
                                   3-15

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      While it is  beyond  the  scope  of this  analysis  to  place a doller value
 on  reputation loss  or to estimate  the dollar  value  of  lost revenues and
 profits,  it is possible  to evaluate  the  probability for  increased costs.
 This  probability  is assumed  to  be  inversely proportional to the degree of
 substitutability.
 3.4.1.1   Cleanliness
      The  Technical  Analysis  component of this section  concludes that
 petroleum solvent is  highly  comparable to  perc in cleaning ability.
 Therefore,  it is highly  probable that commercial and industrial dry cleaners
 will  not  suffer in  this  aspect  of  product  quality.  Consequently, no added
 costs due to  substitution are forecast.
 3.4.1.2   Timeliness
     As mentioned previously, the  use  of petroleum  solvent does not prolong
 the time  of returning  dry cleaned  articles to customers.  With no decline
 in this area  of product  quality due  to substitution, no added costs are
 foreseen.
 3.4.1.3   Damage
     Because  petroleum solvents are  less aggressive than perc, they are
 less likely to damage articles than  perc.  Since there is no loss of
 product quality from this perspective, it is assumed that substitution  will
 impose no added costs.
     Technically, petroleum solvents are complete substitutes  for
 perchloroethylene in dry cleaning.   Therefore, substitution of petroleum
 solvents  for  perc should impose neither additional  costs to dry cleaners in
 loss of customer good will nor in lost revenues  and lost profits.
 3.4.2  Capital and Annualized Costs of Substitution
     Capital costs include the expense of any new equipment and the  labor,
materials, and miscellaneous  expenses of installing and making it operational.
Capital  costs are particularly relevant in  assessing the economic  feasibility
of converting an existing perc dry  cleaning facility to one which  uses
petroleum solvents.   As pointed  out previously in this  section,  perc equipment
                                     3-16

-------
 cannot  use  petroleum solvent without  major  equipment modification.
 Therefore new equipment, specifically manufactured  for  petroleum solvent
 use, must be purchased.
     Annualized operating costs are estimated  for both  perc and petroleum
 dry cleaning facilities.  As previously  stated, these cost comparisons are
 based on model plants, which represent a  range of dry cleaning facilities
 in terms of capacity and nature of service  (i.e. commercial or industrial).
 Annualized cost comparisons are relevant  in assessing the economic feasibility
 of both existing plant conversions and new  plant construction.  Comparing
 key line item operating costs shows the  incremental cost of conversion.
 This is the additional cost burden attributable to  substitution which will
 recur annually.
 3.4.2.1  Model Plant Parameters
     The annualized operating costs of perc and petroleum plants are
 compared in three model plants.  Each plant represents a range of plant
 characteristics typical within the industry.  The parameters for the model
 plants are summarized in Tables 3-5 and 3-6.  The plants compared are a
 small commercial  plant, a large commercial plant, and an industrial  plant.
 Both the perc and petroleum plants are equipped with solvent recovery
 equipment.   For the perc equipment, a carbon adsorption system is used for
 recovery.   As previously mentioned, the petroleum plant is equipped  with a
 recovery dryer.  The perc plant is assumed to use a dry-to-dry machine.
 3.4.2.2  Capital  Costs
     Capital costs  for three petroleum model plant facilities  are presented
 in Tables  3-7, 3-8, and 3-9.  The new pieces of equipment that need  to be
 purchased  as a result of converting from perc to petroleum solvents  are a
washer,  a  recovery  dryer, a  water chiller for the dryer, a vacuum still,
and a solvent storage tank.   Equipment costs were obtained from manufacturers
and equipment vendors.   Taxes,  freight and instrumentation are treated as a
single component  and calculated at 18 percent of equipment costs.31
 Installation costs  are  estimated on the  basis that all  control  equipment
and process  equipment are installed by an outside  contractor at 10 percent
                                      3-17

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                           TABLE 3-5.  PERCHLOROETHYLENE MODEL PLANT PARAMETERS
                                                                               33
to
I
00
Parameter
Annual plant throughput,
kg (Ibs)
Days of operation per year
Throughput description
Number of washers
Washer capacity, kg (Ibs)
Average washer load weight,
kg (Ibs)
Number of washer loads per day
Wash cycle time, minutes

Small
commercial
14,625
(32,243)
250
General apparel
1
11
(25)
9
(20)
6.5
57a
Model plants
Large
commercial
29,250
(64,485)
250
General apparel
1
23
(50)
18
(40)
6.5
57a

Industrial
280,800
(619,058)
260
Industrial articles
1
114
(250)
90
(198)
12
35b
      For dry-to-dry machines.

      For transfer machines.

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                               TABLE 3-6.  PETROLEUM MODEL PLANT PARAMETERS
                                                                            34
co
i
Parameter
Annual plant throughput,
kg (Ibs)
Days of operation per year
Throughput description
Number of washers
Washer capacity, kg (Ibs)
Average washer load weight,
kg (Ibs)
Number of washer loads per day
Wash cycle time, minutes
Number of recovery dryers
Dryer capacity, kg (Ibs)
Dryer cycle time, minutes
Number of vacuum stills
Vacuum still capacity,
1/hr (gal/hr)

Small
commercial
15,000
(33,069)
250
General apparel
1
16
(35)
10
(22)
6
20
1
23
(50)
25
1
95
(25)
Model plants
Large
commercial
32,000
(70,548)
250
General apparel
1
23
(50)
16
(35)
8
25
1
45
(100)
30
1
189
(50)

Industrial
260,000
(573,202)
260
Industrial articles
1
114
(250)
100
(220)
10
40
3
45
(100)
40
1
1,894
(500)

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      TABLE 3-7.  CAPITAL COSTS FOR CONVERTING A SMALL COMMERCIAL MODEL
                  PLANT TO PETROLEUM SOLVENT31,32,35
Description
Equipment
16 kg washer/extractor
23 kg recovery dryer
Water chiller for dryer
100 1/hr vacuum still
760 liter solvent storage tank

Taxes, freight, instrumentation
Equipment installation0

Quantity

1
1
1
1
1
Subtotal


Total
Cost3

7,500
15,640
2,320
2,100
600
28,160
5,070
2,816
36,046
 First quarter 1981  dollars.
 Equals 18 percent of equipment costs
cEquals 10 percent of equipment costs
                                    3-20

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      TABLE 3-8.  CAPITAL COSTS  FOR CONVERTING  A  LARGE  COMMERCIAL MODEL
                  PLANT TO PETROLEUM SOLVENT31,32,36
Description
Equipment
23 kg washer/extractor
23 kg recovery dryer
Water chiller for dryer
190 1/hr vacuum still
760 liter solvent storage tank

Taxes, freight, instrumentation
Equipment installation0

Quantity

1
1
1
1
1
Subtotal


Total
Cost3

13,400
15,640
2,320
4,200
600
36,160
6,510
3,616
46,286
 First quarter 1981 dollars.
 Equals 18 percent of equipment costs.
cEquals 10 percent of equipment costs.
                                    3-21

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        TABLE 3-9.  CAPITAL COSTS FOR CONVERTING AN  INDUSTRIAL MODEL
                    PLANT TO PETROLEUM SOLVENT31,32,37
Description
Equipment
115 kg washer/extractor
45 kg recovery dryer
Water chiller for dryer
1900 1/hr vacuum still
15,150 liter solvent storage tank

Taxes, freight, instrumentation
Equipment installation0

Quantity

1
3
3
1
1
Subtotal


Total
Cost3

55,000
48,540
7,880
51,390
1,500
164,310
29,576
16,431
210,317
 First quarter 1981 dollars.
 Equals 18 percent of equipment costs,
""Equals 10 percent of equipment costs,
                                    3-22

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                      32
of the equipment cost.    It is important to note that the petroleum
equipment costs include a recovery dryer.  As previously mentioned,
recovery dryers are the type of dryer expected to be used by the petroleum
sector of the industry in the future.  The recovery dryer and the required
water chiller equipment constitute a significant percentage of the total
cost.  For example, in a small  commercial plant, these items represent
64 percent of the equipment cost; 50 percent in a large commercial plant;
and 34 percent in an industrial plant.  As will be seen later in this
section, the recovery dryer's expense as a capital item contributes  to a
substantial savings in annualized operating costs.
3.4.2.3  Annualized Operating Costs
     The relevant operating costs which are estimated include:   solvent;
steam; electricity; operating labor; maintenance; overhead expenses  of
administration, taxes, and insurance; and capital recovery.  Annualized
costs of converting from perc to petroleum solvents range from approximately
$1,200 for a small  commercial plant to $9,200 for an industrial  plant.   In
estimating comparative solvent costs, the amount of solvent consumed each
year is assumed to be equal to the amount of solvent lost during the
drying cycle, which is equal to the amount of solvent emitted from the
dryer minus the amount of solvent recovered by solvent recovery devices.
Perchloroethylene consumption has been conservatively estimated to be about
5.0 kg per 100 kg of clothes cleaned (or about 0.36 gallons per 100  Ibs).38
Uncontrolled petroleum solvent losses from drying have been conservatively
estimated to be 18.9 kg per 100 kg of clothes cleaned (or about 2.9  gallons
             39
per 100 Ibs).   Tests conducted on recovery dryers show that between
65 and 95 percent of the petroleum solvent normally vented to the atmosphere
                 40
can be recovered.    For the purpose of this study an average solvent
recovery rate of 80 percent is assumed.  Reducing petroleum solvent  losses
80 percent with a recovery dryer results in a total dryer solvent loss rate
of 3.8 kg per 100 kg of clothes cleaned (0.6 gallon per 100 Ibs).  Total
solvent emissions with a recovery dryer are roughly 8.0 kg per 100 kg of
                                           38
clothes cleaned (1.25 gallons per 100 Ibs).    Perc is valued at $0.57 per
kg ($3.50 per gallon).     The solvent cost of dry cleaning with  perc  i
                                                                      s
computed to be $2.80 per 100 kg of clothes cleaned.   Petroleum solvents  are
                                       ,n).4C
                                       3-23
valued at $0.56 per kg  ($1.65 per gallon).     The solvent  cost  of  dry

-------
 cleaning with petroleum solvents  is computed to be $4.48 per 100 kg of
 clothes cleaned.  Thus, perc has  a slight cost advantage over petroleum
 solvents under the given assumptions.  Tables 3-10, 3-11, and 3-12 summarize
 comparative annual solvent costs  for each model plant.
     For an average dry-to-dry machine, the steam requirement for drying is
 2.9 boiler horsepower (BMP) per 100 Ibs. of clothes cleaned.    A recovery
 dryer requires 2.5 BMP per 100 Ibs. of clothes cleaned.    Therefore, a
 perc machine requires about 0.4 BMP more than a petroleum recovery dryer
 per 100 Ibs. of clothes cleaned.  Steam costs about $0.12 per BHP.    The
 difference in the cost of steam between perc and petroleum solvent is
 $0.05 per 100 Ibs. of clothes cleaned.  Tables 3-10 thru 3-12 show perc and
 petroleum plants to have comparable annualized steam costs.
     Comparative annual  costs of electricity show a general parity between
 petroleum and perc plants.   Electricity costs, calculated from manufacturer's
 literature and based on $0.06 per kWh, show that a small commercial  perc
 washer costs $24 less to operate annually than a small commercial  petroleum
 washer and dryer combination, while an industrial  perc washer costs  $310
 more to operate annually than an industrial  petroleum washer and dryer
            44 45
 combination.   '
     Labor requirements  for operating dry cleaning machinery in  perc and
 petroleum plants is assumed to be the same for each type plant.   Labor
 costs range from $4,300  per year for a small  commercial plant to $11,160 per
year for an industrial  plant.
     Maintenance costs  associated with dry cleaning are also assumed to be
 the same for perc and petroleum plants.   Annual  maintenance cost range from
 $830 for a  small  commercial  plant to $3,590  for an industrial  plant.46
     Overhead,  consisting of taxes,  insurance and  administrative costs, is
estimated  to  be four percent of the  equipment costs.40  Overhead costs
range from  between $1,442 for a small  commercial  plant to $8,413 for an
industrial  plant, and are assumed to be  the  same for  perc and  petroleum
plants.
                                     3-24

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    TABLE  3-10.  COMPARATIVE ANNUALIZED  OPERATING  COSTS  OF  USING  PETROLEUM
                SOLVENT AND PERC  IN A SMALL  MODEL PLANT

Operating costs
Solvent
Steam
Electricity
Labor
Maintenance
Adm. , ins. , and taxes
Capital recovery
SUBTOTAL
Perc plant
costs, $
(A)

417
112
103
4,300
830
1,442
3,023b
10,227
Petroleum
plant costs, $
(B)

672
99
127
4,300
830
1,442
3,990C
11,460
Increase
in cost, $
(B - A)

255
(13)a
24
0
0
0
967
1,233
aNet credit.

 Capital  recovery is based  on an existing perc machine with a purchase price
 of $23,000;  the estimated  useful  life is 15 years and the interest rate
 is 10 percent.   Reference  39.

cCapital  recovery is based  on a  new petroleum washer, dryer, still, and
 storage  tank with a total  installed cost of $36,000, an estimated  useful
 life of  30 years, and an  interest rate of 10 percent.  Reference 40.
                                    3-25

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TABLE 3-11.  COMPARATIVE ANNUALIZED OPERATING COSTS OF USING PETROLEUM SOLVENT
             AND PERC IN A LARGE COMMERCIAL MODEL PLANT

Operating costs
Solvent
Steam
Electricity
Labor
Maintenance
Adm. , ins. , and taxes
Capital recovery
SUBTOTAL
Perc plant
costs, $
(A)

834
225
117
5,720
830
1,851
3,825b
13,402
Petroleum
plant costs, $
(B)

1,434
212
264
5,720
830
1,851
5,124C
15,432
Increase
in costs, $
(B - A)

600
(13)a
147
0
0
0
1,299.
2,033
aNet credit.

 Capital recovery is based  on an existing perc machine with a purchase price
 of $29,000; the estimated  useful  life is 15 years and the interest rate
 is 10 percent.   Reference  39.

cCapital recovery is based  on a new petroleum washer, dryer,  still, and
 storage tank with a total  installed cost of $46,300, an estimated  useful
 life of 30 years, and  an interest rate of 10 percent.  Reference 40.
                                    3-26

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    TABLE  3-12.  COMPARATIVE ANNUALIZED  OPERATING COSTS OF USIKG PETROLEUM
                SOLVENT AND PERC  IN  AN  INDUSTRIAL MODEL  PLANT

Operating costs
Solvent
Steam
Electricity
Labor
Maintenance
Adm. , ins. , and taxes
Capital recovery
SUBTOTAL
Perc plant
costs, $
(A)

8,003
2,154
1,670
11,160
2,590
8,413
17,091b
51,081
Petroleum
plant costs, $
(B)

11,648
1,857
1,360
11,160
2,590
8,413
23,282C
60,310
Increase
in costs, $
(B - A)

3,645
(297)a
(310)
0
0
0
6,191
9,229
aNet credit.

 Capital  recovery is  based on an existing perc machine with a  purchase price
 of $130,000;  the estimated useful  life is 15 years and the interest rate
 is 10 percent.   Reference 3B.

cCapital  recovery is  based on a new petroleum washer,  dryer,  still,  and
 storage  tank  with a  total installed cost of $210,300, an estimated  useful
 life of  30 years, and  an interest  rate of 10 percent.  Reference  40.
                                     3-27

-------
     The capital  recovery cost for the perc plant is  based  on  a  10  percent
                                                         41
interest rate and an expected equipment life of 15 years.     For the
petroleum plant,  capital  recovery is based on a 10 percent  interest rate
and a 30 year equipment life.    The Halogenated Cleaning Solvents  Association
(HCSA) has suggested that although a 30 year life expectancy  for a  petroleum
washer may be possible, a 15-year life expectancy may be more  realistic
in view of technological  changes and increasing equipment maintenance
costs as the washer ages  (see HCSA comments in Appendix B).
3.4.2.4  Costs of Fire and Building Code Compliance
     In addition  to capital  and operating costs, there is another factor
unique to the analysis of substituting petroleum solvent for  perc.  This
is the cost of additional materials and labor required to bring  an  existing
or new facility into compliance with local fire and building  codes.  The
Technical Analysis section discussed the additional safety  requirements
imposed on petroleum solvent dry cleaning facilities.  From an economic
perspective, these requirements are important in determining  the feasibility
of substitution.   There are two reasons for this.  First, the magnitude
of the added costs to build or convert to a petroleum solvent facility
can be great.  For example, the Southern Building Code Congress  estimates
an average 30 percent increase in construction costs (per square foot) to
build a Type 2 versus a Type 5 building.  Type 2 is a category of building
construction required for petroleum dry cleaners because of to the  low
flashpoint of petroleum solvents.  A Type 5 building has "normal" construction
                47
characteristics.     Costs of conversion could include rewiring,  fire
walls, and boiler modifications to provide an explosion-resistant
facility.  The second reason that fire and building code requirements are
crucial to this analysis is that they pose potential logistical  as  well
as economic constraints in the case of converting an existing plant.   A
scenario in which an existing perc plant  is required to convert to petroleum
solvent might find an establishment physically unable to make the conversion,
the added cost notwithstanding.  This would leave the proprietor with the
option of finding new space relocating the dry cleaning equipment while
maintaining a storefront in the same location, or going out of business.
                                   3-28

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3.5  CONCLUSIONS AND RECOMMENDATIONS
     The substitution of petroleum solvents for perc is feasible on the
basis of product quality and of physical  replacement of perc equipment
with petroleum equipment.  Capital costs  of conversion range from $36,000
for a small commercial  establishment to $210,000 for a large industrial
plant.  This study did not determine the  ability of the user to pay these
costs.  In addition to the capital costs  of conversion, local  fire codes
may require expensive remodeling of the building, which is not always
possible when the dry cleaner is located  in a leased space or a shopping
center.  Fire codes in some cities make substitution of petrolum solvents
for perc illegal, a situation that can be determined on an area-by-area
basis.  While substitution of petroleum solvents for perc is technically
feasible, fire codes are the primary obstacle to converting to petroleum
solvents in the dry cleaning industry.  In addition, the limited availability
of petroleum washers and dryers, and solvent stills places a constraint
on the rate at which the industry could convert from perc to petroleum
solvents.
                                  3-29

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3.6  REFERENCES

 1.  United States Environmental Protection Agency.  Perchloroethylene Dry
     Cleaners - Background Information for Proposed Standards.  Office of Air
     Quality Planning and Standards.  Research Triangle Park, NC.
     EPA-450/3-79-029a.  August 1980.  p. 3-2 to 3-3.

 2.  Reference 1, pg. 3-7.

 3.  United States Environmental Protection Agency.  Petroleum Dry Cleaners -
     Background Information for Proposed Standards (Preliminary Draft).
     Office of Air Quality Planning and Standards.  Research Triangle Park,
     N.C.  November 1981.  p. 4-1.

 4.  Reference 3, pg. 3-1.

 5.  Reference 1, pg. 3-4.

 6.  Reference 3, pg. 3-3.

 7.  United States Environmental Protection Agency.  Control of Volatile
     Organic Emissions from Perchloroethylene Dry Cleaning Systems.
     EPA-450/2-78-050.  Office of Air Quality Planning and Standards.
     Research Triangle Park,  NC. December, 1978.

 8.  Personal  communication.   Lester Y.  Pilcher,  GCA Corporation with
     Bud Sluizer, Institute of Industrial  Launderers.   October 6, 1981.

 9.  Reference 3, pg. 3-1.

10.  National  Fire Protection Association.   Standard for Drycleaning Plants.
     NFPA 32-1979.  Quincy,  MA.

11.  Materials balance provided  to  GCA Corporation by EPA Toxic Substances
     Priority Committee,  August  27,  1981.

12.  Personal  communication.   Timothy Curtin,  GCA Corporation with
     Steve Plaisance, TRW, RTP,  NC.   September 24,  1981.

13.  Johnson,  Keith.   Dry Cleaning  and Degreasing Chemicals  and Processes.
     Park Ridge,  NO.   Noyes  Data Corporation,  1973.  pp.  3-36.

14.  Personal  communication.   Samuel  Duletsky, GCA Corporation  with
     William Fisher,  International  Fabricare  Institute,  Silver  Spring,  MD.
     November  3,  1981.
                                     3-30

-------
 15.   Personal communication.  Samuel Duletsky, GCA Corporation with
      Frank Vitek, National Automatic Laundry and Cleaning Council, Chicago,
      IL.  October 23, 1981.

 16.   Personal communication.  Samuel Duletsky, GCA Corporation with Tom Briggs,
      International Conference of Buildings Officials, Whittier, CA.
      November 19, 1981.

 17.   Personal communication.  Samuel Duletsky, GCA Corporation with Paul  Spurgeon,
      Fire Prevention, Denver, CO.  November 10, 1981.

 18.   Personal communication.  Samuel Duletsky, GCA Corporation with
      Captain Hudson, Fire Prevention, Phoenix, AX.  November 10,  1981.

 19.   Letter from Joseph  C. Hess, Chief of Fire Prevention of the  City of New
      York, to Samuel Duletsky, GCA Corporation, December 8,  1981.

 20.   Reference 3, pg. 9-2.

 21.   Chemical Economics  Handbook, SRI International,  Menlo Park,  CA,  p.  300.3700E.

 22.   Personal communication.  Samuel Duletsky, GCA Corporation with
      Buddy Whitlock, Ashland Oil Company, Columbus, OH.   November  4,  1981.

 23.   Personal communication.  Samuel Duletsky, GCA Corporation with
     Jim Watson, Getty Refining and Marketing Company,  Tulsa,  OK.
     November 4, 1981.

 24.  Personal communication.  Samuel Duletsky, GCA Corporation with
     Jim Montgomery, Washex Machinery Corporation, Wichita Falls,  TX.
     November 4, 1981.

 25.  Personal communication.  Samuel Duletsky, GCA Corporation with
     Gordon Carruth, Marvel  Manufacturing Co., San Antonio,  TX.
     November 10, 1981.

 26.  Personal communication.  Samuel Duletsky, GCA Corporation with
     Ray McMonagle,  VIC  Manufacturing Co., Minneapolis,  MN.
     November 10, 1981.

 27.  Personal communication.  Samuel Duletsky, GCA Corporation with
     Albert Jenkins, Four State Machinery Manufacturing  Co., Joplin,  MO.
     November 13, 1981.

28.  Personal communication.  Samuel Duletsky, GCA Corporation with
     Derek Oakes, Hoyt Manufacturing Corp.,  Westport  MA.   November 5, 1981.

29.  Reference 3, p.  9-15.

30.  Reference 3, p.  9-4.

31.  Reference 3, p.  8-1.


                                     3-31

-------
32.  Reference 3, p. 8-3.
33.  Reference 1, p. 6-2.
34.  Reference 3, p. 6-3.
35.  Reference 3, pp. 8-2 and 8-4.
36.  Reference 3, pp. 8-2 and 8-5.
37.  Reference 3, pp. 8-2 and 8-7.
38.  Personal communication.  Richard Rehm, GCA Corporation with Steve Shedd,
     U.S. Environmental Protection Agency, Research Triangle Park,  NC,
     February 23, 1982.
39.  VIC Manufacturing Company.  Let's Compare the Costs of Perc and
     Petroleum.  Brochure.  1981.
40.  Reference 3, p. 8-9.
41.  Personal Communication.  Hugh F. Rollins, GCA Corporation  with
     Ray McMonagle,  VIC Manufacturing Co., Minneapolis,  MN.   November 25,  1981
42.  Reference 3, p. 8-11.
43.  Reference 3. p. 8-10.
44.  VIC Manufacturing Company.  Specifications-Models 405-406-406  FS-424.
     Number 2/81.
45.  Washex Machinery Corporation.  Product Specification Sheet for Floataire
     250-pound Washer.  Number SB-289c.
46.  Reference 3, pp. 8-14 to 8-17.
47.  Personal communication.  Hugh'F. Rollins, GCA Corporation  with
     John Parham, City of Durham, N.C.  December 7, 1981.
                                     3-32

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                            4.0  SURFACE COATINGS

4.1  GENERAL DESCRIPTION OF USE
     Surface coatings have a wide variety of uses, such as decoration,
weather and chemical  protection, and safety marking.   Surface coatings
are grouped into three main categories:   architectural  paints, product
finishes, and special purpose coatings.   Architectural  paints are formulated
for application to interior and exterior surfaces of  buildings.   Product
finishes are formulated for factory application on a  range of items
including automobiles, appliances, furniture, metal containers and
aircraft.  Special purpose coatings are formulated for special applications
or environmental conditions and include industrial maintenance paints,
automotive refinishes, traffic paints and aerosol paints.
     Surface coatings are typically composed of three basic components:
(1) a film-forming binder consisting of resins or drying oils, (2) a
dispersion medium of volatile solvents or water which maintains fluidity,
and (3) a pigment system containing coloring and opacifying materials
and various extenders.  The binder plus the solvent is referred to as
the vehicle.  When a coating is applied to a substrate, the volatile
solvent evaporates, leaving the binder and pigment to form an adherent
film.1
     There are three major types of coatings:  paints, lacquers, and
varnishes.  All paints contain pigments.  Solvent-based paints dry by a
combination of oxidation and polymerization of the binder after evaporation
of the solvent, while water-based paints form films by coalescence of
the binders and pigments as the water evaporates.  Most lacquers are
pigmented materials and dry by the evaporation of their volatile components.
Varnishes are clear coatings with no pigmentation, and as with solvent-
based paints, cure through a polymeric reaction of the binder with the
                                               2
oxygen in air after evaporation of the solvent.
                                     4-1

-------
     Chlorinated solvents, because of their expense,  are not used to a
great extent in the formulation of surface coatings.   However,  available
information indicates that they are used to a small  extent in some
painting operations.  Methylene chloride is used as  a solvent in some
traffic and aerosol paints while 1,1,1-trichloroethane is used  as a
solvent in some traffic paint formulations.  According to the National
Paint and Coating Association (NPCA), of the approximately 1.8  million
megagrams (2.0 million tons) of solvents used annually in the formulation
of coatings, only 7,700 megagrams (8,500 tons) or 0.4 percent is methylene
chloride (the only chlorinated solvent for which the  NPCA has consumption
data).3  Other sources estimate that about 7.5 percent of all solvents
used annually in traffic paints is 1,1,1-trichloroethane.
     Because 1,1,1-trichloroethane and methylene chloride are not photochemically
reactive, they are being marketed aggressively as substitutes for various
aliphatic and aromatic solvents presently used in surface coating operations.
Thus, the amount of 1,1,1-trichloroethane and methylene chloride used in
traffic paints and aerosol paints may actually increase.  Use of
1,1,1-trichloroethane and methylene chloride may expand to other surface
coating operations including architectural coatings  and product finishes.
This report does not examine the potential impact of this expansion.
Rather, it examines the practicality of replacing chlorinated solvents
with conventional solvents.
4.2  TECHNICAL ANALYSIS OF SUBSTITUTES
     This section assesses and discusses the available substitutes for
methylene chloride in aerosol paints, and methylene  chloride and
1,1,1-trichloroethane in traffic paints, the effect  of substitution of
these solvents on product quality, and the resource  availability of the
substitute solvents.
4.2.1  Aerosol Paints
     Aerosol paints contain a propellant in addition to the three major
coating components (binder, pigment system and solvent).  The propellants
used in aerosols are typically low molecular weight hydrocarbons such as
                                    4-2

-------
propane, isopropane, butane,  and isobutane.   A wide variety of resin
and pigment systems are used.   Aromatic hydrocarbons,  such as  toluene
and xylene, and oxygenated solvents, such as acetone and methyl  ethyl
ketone, generally are used as primary solvents.   Methylene chloride  is
used frequently as a cosolvent, usually comprising five to ten percent
of the formulation,6 and in some cases as high as 30 percent.    It is
estimated that approximately 5,700 megagrams3 (6,300 tons) to  6,600 megagrams
(7,300 tons) of methylene chloride are used annually in the formulation
of aerosol coatings.  Methylene chloride is used because of its good
solubility properties, rapid rate of evaporation, high specific gravity,
and because it aids atomization, acts as a vapor pressure depressant  for
high pressure propellents, and reduces flammability. ' '
4.2.1.1  Substitutes
     Potential solvent substitutes for methylene chloride in aerosol
paint formulations are listed with selected physical properties in
Table 4-1.  Substitution for methylene chloride may involve an increase
in the amount of the existing primary solvent or solvent blend, or the
addition of a different solvent.  Substitution of solvents may involve
more than a "one-for-one" substitution, because aerosol paint formulations
are complex mixtures of substances.  The substitute solvent must have
similar solubility  properties in relation to the resin systems and
propellent when used in conjunction with other solvents in the formulation.
A  change  in solvent may change  the  properties  of the complete aerosol
                                                 11
system  and must be  studied for  each formulation.
 Calculated  from mass  balance estimates of the total  use of methylene
 chloride  in  aerosol  formulation  (40,500 Mg/yr)1* and  the percentage of
 aerosol units  containing coatings  and  finishes (14 percent).8'9

 Estimated  from NPCA data  assuming that all usage of methylene chloride
 listed  as "miscellaneous"  is  in  aerosol paints.  Usage of methylene
 chloride  in  aerosol  paints is not  listed  separately  and the primary use
 of methylene chloride  other than the  separately listed categories  is in
 aerosol paints.
                                     4-3

-------
     The selection of a solvent substitute is dependent on "its ability to
maintain the homogeneity of the aerosol system.  This ability is a function
of the substitute's solubility characteristics.  Table 4-1 lists the
solubility parameters of potential substitute solvents.   Solubility
parameters may be used as an indication of the relative solvency power of
chemicals.  In general, as the solubility parameter increases, the solvent
becomes more powerful.  The solubility parameter of methylene chloride is
9.7.  Of the solvents listed, the alcohols exhibit solubility parameters
ranging from 11.4 to 14.5, esters in the range of 9.1 to 9.5, ketones from
8.3 to 10.0, aromatics at 8.9 and the aliphatics in the range of 7.3 to
7.4.
     The solubility characteristics of solvents must be assessed in the
context of the specific formulation.  The major resin systems that are used
in coating formulations and compatible solvents are as follows:
     Al_ky_d_--Alkyd resins are the condensation products of saturated polycarboxylic
acids and polyfunctional alcohols modified by fatty acids.  Phthalic
anhydride is used in about 85 percent of all alkyds produced.  The type of
solvent used in alkyd coatings is dependent on the molecular weight of the
resin and the amount of oils present.  Short oil-length and medium
oil-length alkyd resins are compatable with aromatics, esters and alcohols.
     Acrylic—Acrylic resins are predominantly polymers and copolymers of
esters of acrylic and methacrylic acid and require relatively strong
solvents such as toluene, xylene, acetone or methyl ethyl ketone.
     Epoxy—Epoxy resins are polymers containing a three-membered epoxide
ring containing two carbon atoms and one oxygen atom.  The cosolvents used
for most unmodified epoxy resins are ketones, esters,  and glycol ethers.
     Ure_tha_ne_s_--lire thane resins are polymers formed by the reaction of
isocyanates and alcohols.  Nonreactive urethane resins are dissolved  in
aliphatic or aromatic hydrocarbon solvents.  Urethane  lacquers  and  reactive
urethane  resin systems  require oxygenated solvents  (typically ethyl acetate
and butyl acetate) as primary  solvents and aromatic solvents as  diluents.
 cThe  solubility  parameter  is  the  square  root  of  the  cohesive  energy  density
 which is  the  summation  of  interaction  energies between  molecules.12
                                      4-4

-------
            TABLE 4-1.  POTENTIAL SOLVENT SUBSTITUTES  FOR METHYLENE CHLORIDE  IN AEROSOL PAINTS
                                                                                              13
en
Solvent
Alcohols
Methanol
Ethanol
Isopropanol •
Ketones and esters
Acetone
Methyl ethyl ketone
Methyl acetate
Ethyl acetate
Aliphatic hydrocarbons
Hexanes
Heptanes
Aromatic hydrocarbons
Toluene
Xylene
Methyl ene chloride3
Specific
gravity
((a 20/20°C)

0.793
0.792
0.787

0.792
0.806
0.904
0.902

0.675
0.69

0.872
0.871
1.32
Solubility
parameter

12.8
14.5
11.4

10.0
9.3
9.5
9.1

7.3
7.4

8.9
8.9
9.7
Distillation
range

64-65
74-80
82-83

55.5-56.5
79-80
53-59
76-79.5

66-70.5
93.6-98.4

110-111
130-140
40.0-40.8
Evaporation
rate
(n-Butyl
acetate = 1)

3.5
1.9
1.7

7.7
4.6
11.8
4.1

8.1
4.5

1.5
0.75
14.5
Vapor
pressure
(mm Hg
9 20°C)

96
44
31

185
70.6
26.3
76

140
45

38

352
      'included  for comparison purposes only.

-------
     Cellulosics--The major cellulosic resin used is nitrocellulose.
Cellulose acetate, cellulose butyrate, and ethyl cellulose are used to a
much lesser extent.  Solvents used in cellulosic coatings are typically
lower molecular weight ketones, esters, and glycol ethers.
     Vinyl--Most of the vinyl resin systems used in coatings are polymers
and copolymers of vinyl acetate and vinyl chloride and can be dissolved in
                   1 14
ketones and esters. '
     The hydrocarbon propellants generally used in aerosol paint formulations
typically have poor solubility characteristics.    In some cases a change
in the solvent system could require a change in propellant.  Dimethyl  ether
has been identified as a possible substitute propellant for aerosol systems
in which methylene chloride is used as a co-solvent.  Because of its better
solubility properties relative to the hydrocarbons, it could possibly  be
used as a propellant when change in a solvent system containing methylene
chloride result in a loss of homogeneity in the system.
     Choice of the solvent substitute is also dependent on the ability of
the solvent to maintain the application properties of the coating.  The
rate of evaporation of a solvent or solvent blend from a coating is important
in spray application.   If a solvent evaporation rate is too fast,  too  much
solvent leaves the coating prior to contact with substrate resulting in
stringing or cobwebbing of the spray or rough surfaces and "orange-peeling"
of the paint film on the substrate.  If the solvent evaporation rate is too
slow, the coating will  tend to sag or run.     The evaporation rate of  a
solvent from a coating depends on a number of factors including:   temperature
of the fluid, temperature of the air above the fluid, air movement, surface
tension, humidity, solvent vapor pressure,  and solvent-resin interactions.18
Table 4-1  lists vapor pressures and evaporation rates of solvents  which are
parameters that are indicative of the rate at which solvents are released
from aerosol  paints during drying.   Evaporation rates of solvents  are  not
absolute values and thus are shown relative to the rate of evaporation of
n-butyl  acetate.   None of the potential  substitute solvents have evaporation
rates as fast or vapor pressures as high as methylene chloride,  which  has
an evaporation rate relative to n-butyl  acetate of 14.5 and a vapor pressure
                                    4-6

-------
of 340 mm Hg at 20°C.   The high vapor pressure of methylene chloride assists
in atomization of the paint.  In addition, none of the potential  substitute
solvents have specific gravities as high as methylene chloride.   Because of
this, aerosol paints formulated with less dense solvents may not  be able to
meet government procurement specifications that require aerosol  paints to
contain 13 ounces by weight per 16 ounce volume can.
     Substitution of solvents for methylene chloride  in aerosol  paints is
considered to be technically feasible for the majority of formulations.
One company estimated that approximately 10 percent of aerosol  paint formulations
would not tolerate substitution of methylene chloride by another  solvent.
4.2.1.2  Effect of Solvent Substitution on Product Quality
     Because substitutes are generally slower evaporating than  methylene
chloride, coatings formulated with substitute solvents may have more of a
tendency to run or sag; however, these effects should not be significant.
A few companies that have been substituting other solvents for  methylene
chloride where possible because of its expense have stated that the product
quality has been maintained in these paints. '  '
4.2.1.3  Resource Availability
     Since the annual use of methylene chloride in the formulation of
aerosols is estimated to be only about 5,700 megagrams (6,300 tons) to
6,600 megagrams (7,300 tons), it is anticipated that there will  be an
adequate supply of solvent substitutes.
4.2.2  Traffic Paints
     Traffic paints are applied to streets, highways, airport runways and
other pavement areas where markings are needed.  Traffic paints are sold by
competitive bid to Federal, State, and local governments and independent
marking companies.  The majority of the paints are based on alkyd resin
systems.  Chlorinated rubber resins are used to a lesser extent.
According to the NPCA, of the 67,000 megagrams (74,000 tons) of solvents
used annually in the formulation of traffic paints, only 1.6 percent or
1,100 mecagrams (1,200 tons) are methylene chloride.  1,1,1-Trichloroethane
                                      4-7

-------
is also used in the formulation of traffic paints, with an estimated  annual
consumption of 5,000 megagrams (5,500 tons).    Manufacturers of traffic
paint application equipment are issuing warnings that halogenated solvents
in paint formulations cause corrosion of equipment which may result in a
                                                                         20
decrease of the use of chlorinated solvents in traffic paint formulation.
4.2.2.1  Substitutes
     Potential substitute solvents for 1,1,1-trichloroethane and methylene
chloride in traffic paints are the same as those listed for aerosol formulations
in Table 4-1.  The most frequently mentioned are acetone, methyl ethyl
                           20 21 22
ketone, toluene and hexane.          These four solvents and selected
physical properties are listed in Table 4-2 for comparison with methylene
chloride and 1,1,1-trichloroethane.  As in aerosol formulations, the  selection
of the solvent substitute is dependent on the ability of the solvent  to
maintain the homogeneity of the formulation and its application properties.
In addition, traffic paints must meet performance specifications of the
Federal, State or local government for which the paint is formulated.
     Substitute solvents must have solubility characteristics similar to
methylene chloride and 1,1,1-trichloroethane.  With the exception of hexanes,
the substitute solvents have larger solubility parameters than
1,1,1-trichloroethane, while only acetone has a solubility parameter larger
than methylene chloride (see Table 4-2).  Solubility parameters give only a
general indication of relative solvency power.  The solubility characteristics
of the solvent must be assessed in the context of the specific formulation.
Chlorinated solvents are typically used in paints based on chlorinated
rubber resins.  Methyl ethyl ketone and toluene are solvents that are
                                          21
widely used for this type of resin system.    Acetone is also compatible
                               20
with chlorinated rubber resins.
4.2.2.2  Effect of Substitutes on Product Quality
     Traffic paints are evaluated for performance characteristics such as
film thickness of the applied paint, durability, bead retention (retention
of glass beads added to increase the reflectance of the markings), and dry
                   23
or "no track" time.    It is not anticipated that substitution would adversely
                                     4-8

-------
                        TABLE 4-2.   POTENTIAL SOLVENT SUBSTITUTES IN TRAFFIC PAINT
                                                                                  13

Solvent
Acetone
Methyl ethyl ketone
Hexanes
Toluene
Methyl ene chloride3
l,l,l-Trichloroethanea
Specific
gravity
(@ 20/20°C)
0.792
0.806
0.675
0.872
1.32
1.32
Solubility
parameter
10.0
9.3
7.3
8.9
9.7
8.5
Distil
lation
range
55.5
79
66
110
40.0

- 56.5
- 80
- 70.5
- Ill
- 40.8
74
Evaporation
rate
(n-Butyl
acetate = 1)
7.7
4.6
8.1
1.5
14.5
6.0
Vapor
pressure
(mm Hg
@ 20°C)
185
70.6
•140
38
352.1
104.5
I
10
Included for comparison purposes only.

-------
affect the durability or bead retention of applied paints,  and paints
                                                              21
can be formulated with substitutes to maintain film thickness.    However,
solvent substitution would effect the dry time of the applied paint.   For
paints formulated with methylene chloride, substitution of  another solvent
would result in a slower drying paint, since none of the potential substitutes
evaporate as fast as methylene chloride.  Reformulation of  paint originally
using 1,1,1-trichloroethane with acetone and hexanes would  decrease the dry
time, while reformulation with methyl ethyl ketone or toluene would result
in longer dry times.  In general, the impact of solvent substitution on the
                                                              20 21
quality of traffic paints is not considered to be significant.  '  '
4.2.2.3  Resource Availability
     Since chlorinated solvents represent such a small proportion of the
solvents used in the formulation of traffic paints, it is anticipated that
there will be an adequate supply of substitute solvents.
4.3  ECONOMIC ANALYSIS OF SUBSTITUTES
     This section analyzes the economic feasibility of substitutes for
methylene chloride and 1,1,1-trichloroethane in paint formulations processes.
For the purposes of this study, the economic analysis deals only with
estimating the relevant  costs of using  substitutes.  No attempt is made to
assess the user's ability to pay these  costs.  The cost categories analyzed
are costs attributable to a decline  in  product quality and the capital and
annualized operating costs of using  a substitute.
4.3.1  Industry  Structure
     Paint formulation is a production  process within the coatings and
allied products  industry.  This  industry  has three broad sub-groups:
architectural  coatings,  product  coatings  OEM  (original equipment  manufacturers),
and special  purpose coatings.  The processes with which this  analysis  is
concerned, aerosol  paints and traffic  paints, are grouped under  the  special
purpose  coatings category.  As shown  in Table 4-3, both aerosols  and  traffic
paints represent a  relatively small  portion of the coatings  industry  in
terms  of production.24   Aerosols  represent  0.5 to 0.6  percent of  production,
while  traffic  paints  represent 4.5 percent.   In  1977,  aerosol  purchases
                                     4-10

-------
                TABLE 4-3.  1979 PRODUCTION OF SURFACE COATINGS
                                                               24
          Type
   Amount
(106  liters)
Industrial
Architectural
Special purpose
   Industrial maintenance coatings
   Traffic paint
   Auto refinishing
   Other refinishing
   Miscellaneous
      Aerosols
      Other miscellaneous
   Total special purpose
TOTAL
    1,552
    1,628

      107
      166
      134
       34

   19  -  23
   83  -  87
      547
    3,727
                                    4-11

-------
totaled $123.5 million compared with total  coatings  purchases  of $6.12 billion,
or approximately 2 percent of the total  value of purchases.   Traffic paint
represented 0.6 percent of the total value  of purchases in 1977.
Table 4-4 summarizes estimated employment and financial data for the industry
for 1980.
     Paint formulation takes place in approximately  1,150 to 1,300 companies
which operate approximately 1,600 manufacturing facilities.   The geographical
and size distribution of paint manufacturing facilities that responded to a
survey of the industry conducted by the Environmental  Protection Agency are
listed in Table 4-5.  The results of this survey showed that the industry
contains a large proportion of small plants with a concentration of plants
in California (14 percent), Illinois (8 percent), New York (8 percent),
                                            27
Ohio (7 percent) and New Jersey (8 percent).
4.3.2  Market Penetration of Substitutes
     The Technical Analysis Section points  out that  the substitutes for
halogenated solvents in aerosol paints and traffic paints are not products,
but rather reformulation which could include adding  a number of new chemicals.
Thus, an analysis of the market penetration of candidate substitutes is not
feasible.  It can be said, however, that there are a number of reformulation
possibilities and the solvents required are known to be commonly used and
commercially available.
4.3.3  Industry Trends
     The trend in the coating industry is toward consolidation with larger
and fewer companies.  While capital and technology requirements have not
been significant barriers to entry  in the past, increasing capital costs
                                                                       28
and energy costs indicate a decline in the number of smaller companies.
It is not known, however, whether this trend will significantly affect the
aerosol  and traffic paint sectors of the industry.  Substitute  processes
probably would be more easily accomplished by larger companies who have the
financial and personnel requirements to accommodate such a change.  Traffic
paints probably will remain at a stable production level as their demand  is
derived  from road construction and  maintenance activities.  Governmental
                                     4-12

-------
          TABLE 4-4.   1980 PROFILE:   PAINTS AND ALLIED PRODUCTS26
SIC Code:  2851
Value of industry shipments (106 $)                        9,335
Value added (106 $)                                        4,014
Total employment (103)                                        59.5
Number of establishments, total (1977)                     1,579
Number of establishments with 20 employees
  or more (1977)                                             653
Exports as a percent of product shipments                      3.3
Imports as a percent of apparent consumption                   0.6
Compound annual rate of change, 1975-80:
    Value of product shipments                                12.9
    Value of exports                                          15.8
    Value of importsb                                         20.0
    Total employment (%)                                      -0.1
                         Major producing States:
              California, Illinois, Ohio, New Jersey, Texas

almports divided by product shipments plus imports minus exports.
bRates of change based on current dollars.
                                  4-13

-------
TABLE 4-5.   GEOGRAPHICAL DISTRIBUTION OF PAINT PLANTS27
Number of plants
EPA Region
Region I
Connecticut
Naine
Massachusetts
ke« Hampshire
Rhode Island
Vermont
Total
Region 11
he* Jersey
he. Tort
Puerto Rico
Virgin Islands
Total
Region 111
Delaware
D.C.
Maryland
Pennsylvania
Virginia
West Virginia
Total
Region IV
Alabama
Florida
Georgia
Kentucky
Mississippi
North Carolina
South Carolina
Tennessee
Total
Region v
Illinois
Indiana
Michigan
Minnesota
Ohio
Wisconsin
Total
Re;1=r. VI
Arkansas
Louisiana
Ne« Keiico
Oklahoma
Tetas
Total
Region Vil
!o-a
Kansas
Missouri
Nebraska
Total
Region VIII
Colorado
Montana
North Dakota
Sough Dakota
Utah
Uyoning
Total
Region IX
Arizona
California
Hawaii
Nevada
Total
Region X
Alaska
Idaho
Oregon
Washington
Total
Accumulative Total
Total
10
3
54
3
5
"77
112
log
6
0
T7I
3
0
?0
66
13
C
TTB

12
69
35
22
S
20
5
17
IB

106
34
47
19
!03
3*
3«5

7
15
3
9
SB
"57

13
10
SI
2
~H '

n
3
0
1
t
TB

6
196
0
I
7B3

1
2
20
22
~K
1.374
0-20
enployees
6
3
36
2
4
-si
60
S4
3
0
1T7
0
0
e
40
6
-57

6
59
20
5
4
9
3
Til

50
22
25
12
60
26
TST

5
11
2
7
Ji
T?

8
6
30
2
TS

e
3
0
1
3
"I?

4
123
0
1
T75

1
2
14
16
T3
S48
20-100
employees
4
0
16
1
1
-73-
37
17
2
0
-R
3
0
10
19
7
li

4
E
10
13
1
7
1
6
TB

38
B
16
6
31
6
TB5

1
t
1
I
-if

4
2
ie
0
~n

3
0
0
0
1
0

2
57
0
0
T5

0
0
6
~rc
396
Over 100
employees
0
0
1
0
0
0
10
6
1
0
T7
0
0
2
6
0
-8

2
0
4
4
0
3
1
~lf

15
4
5
1
10
1
~5E

l
0
0
0
6

1
2
5
0
-B

0
0
0
0
0
0
0

0
12
0
0
-J7

0
0
0
0
—5
105
Not
indicated
0
0
1
0
0
0
5
2
0
0
0
0
0
1
0
0

0
2
1
0
0
1
0
_0

3
0
1
0
2
1
T

0
0
0
1
C

0
0
0
0
T

0
0
0
0
0
0
~B

0
4
0
0
~

0
0
0
0
-5
25
                       4-14

-------
budgets for these activities are expected to remain stable for the next few
                                                                      29
years with a greater emphasis on maintenance than on new construction.
Table 4-6 illustrates the estimated trend for coatings and allied products
through 1981.  While aerosols and traffic paints are not listed as distinct
categories, it is assumed that they will keep their relative share of
demand.
4.3.4  Product Quality
     The Technical Analysis Section reports that substitutes for methylene
chloride in aerosol paints are not likely to alter product quality significantly.
Product quality in aerosols for the general public is primarily related to
the convenience of being able to purchase a small amount of paint for a
specific job.  The quick-drying characteristics of aerosols which produces
a smooth, even finish dominates retail advertising strategy.  This characteristic
is equally important to industrial users.  Any reformulation which would
detract from the quick drying quality of aerosols probably would cause  some
shift away from aerosol usage.  Since there are a number of reformulation
possibilities, however, no product quality decline is foreseen.  Consequently,
no costs are attributed to substitution for this category.  As in aerosols
there are no major technical constraints to reformulation in traffic paints
and no decline in product quality is foreseen.   Thus, there are no substitution
costs attributable to a change in product quality.
4.3.5  Capital and Annualized Operating Costs
     Reformulation would not require the purchase of new production equipment.
Thus, no capital  costs are associated with substitution.   The primary costs
attributable to reformulation are those associated with research and
development and re-printing of labels.  Research and development costs  are
primarily expenses for labor and materials.  Labor estimates required to
complete reformulation vary from 12 to 15 manhours per reformulation to 130
to 160 manhours per reformulation.  '    There  is insufficient data to
place a dollar value on these estimates.  Cost  estimates  for label  changes
vary from "negligible" to $6000 per label.9'32
                                    4-15

-------
                         TABLE  4-6.    PAINTS AND ALLIED  PRODUCTS:   TRENDS AND PROJECTIONS 1975-8128
                                                (millions of current dollars, except as noted)
Item
Industry (SCI 2851)
Value of shipments1
Value added
Value added per production
worker-hour (J)
Total employment (000)
Production workers (000)
Average hourly earnings (Oec.--$)
Year-to-year percent change in average
hourly earnings (Dec. -Dec.)
Capital expenditures
4* Product (SIC 2851)
!-• Value of shipments5
en
Producers Price Index (Dec)6
Year-to-year percent change in
Producers Price Index (Dec. -Dec.)6
Trade
Value of exports
Value of imports
1975

5,150
2,126
34.69
59.9
31.1
5.19
11.6
121.6

4,672
170.2
5.2

137.3
21.2
1976

5.931
2,562
40.09
60.4
31.9
5.59
7.7
122.4

5,415
177.3
4.2

170.9
32.3
1977

6,630
2,821
42.62
61.4
33.0
6.08
8.8
167.4

6,123
185.9
4.9

208.5
38.2
1978*

7,320
3,148
__
61.2
32.6
6.50
6.9
--

6,715
199.1
7.1

221.7
39.9
19792

8,564
3,683
__
61.2
32.1
6.98
7.4
--

7,857
210.7
5.8

248.2
49.7
19802

9,335
4,014
..
59.5
30.7
7.30*
6.7"
—

8,564
236. 87
15. 37

286
53
Percent
change
1979-802

9
9
__
-3
-4
--
„_
--

9
--
~

15
7
Percent
change
1981' 1980-81 3

10,300 10
4,429 10
« — —
„
--
--
	 __
"

9,450 10
_.
—

315 10
60 12
-- Not available.
'Value of all products and services sold  by the paints and allied products industry (SIC  2851).
'Estimated except for hourly earnings,  price indexes, and 1978-79 trade data.
'Forecast.
"As of June 1980; year-to-year percent  change is for June 1979 to June 1980.
5Value of shipments of paints and allied  products produced by all industries.
6December 1967  is the base period for index.
7As of July 1980; year-to-year percent  change is for July 1979 to July 1980.
Source:   Bureau of the Census (Industry and trade data); Bureau of Labor Statistics (hourly earnings and price indexes).  Estimates and  forecasts
         by the Bureau of Industrial  Economics.

-------
     Reformulation is not expected to cause major changes  in the annualized
operating cost of production.   As shown in Table 4-7,  the  price of substitute
chemicals for methylene chloride is lower in many cases;  however,  since
substitution may not be on a one-for-one basis by either  weight or volume,
these figures cannot be used to estimate changes in operating costs.
Substitute solvents are generally less expensive on both  weight and volume
bases, and companies that have replaced methylene chloride in their aerosol
formulations generally have realized a reduction in the cost of formulation.  '   '
     Substitution costs for traffic paints are not expected to be  significant.
As in aerosols, no capital purchases would be required.  Reformulation
costs are expected to be small because review and evaluation is an ongoing
process in the formulation of traffic paints.  It has  been estimated  that
on the average, 30 percent of the manufacturing costs  of  traffic paint is
due to the cost of the solvent.    Comparative costs of solvents for  traffic
paint are listed in Table 4-7.  As in aerosol formulations, since  substitution
of solvent is not likely to be carried out strictly on a  one-for-one  weight
or volume basis, the effect of substitution on the cost of manufacturing
paint cannot be determined specifically.  However, because potential
substitutes are less expensive than 1,1,1-trichloroethane  and methylene
chloride, a reduction in cost can be anticipated.
4.4  CONCLUSION
     Substitution for halogenated solvents in aerosol  paints must  be  done
on a case-by-case basis.  In aerosol paints, the only  significant  costs are
those associated with reformulation.  Among these are  the  costs for
personnel and materials in the research and development of new formulations.
Labor estimates vary from 12 to 15 manhours per reformulation to 130  to
160 manhours per reformulation.  This is likely to be  a one-time cost.
Given the apparent by adequate supply of substitute chemicals, it  is  not
likely that recurring production costs will rise appreciably after substitution.
The absence of any requirements for new capital  equipment  for aerosols is
important.  In an economic sense, substitution in aerosol  paints would
require a minor shift in research and advertising resources.   Labeling
changes occur periodically regardless of whether a new formula is  present.
Thus, the total impact might best be described as a reallocation of

                                   4-17

-------
TABLE 4-7.  PRICES OF SOLVENTS34
Solvent
Methanol
Ethanol
Isopropanol
Acetone
Methyl ethyl ketone
Methyl acetate
Ethyl acetate
Hexane
Heptane
Toluene
Xylene
Methyl ene chloride
1,1,1-Trichloroethane
Cost3
$ per kilogram
0.25
0.64
0.64
0.64
0.77

0.79
0.40
0.40
0.46
0.46
0.67
0.68

$ per liter
0.20
0.52
0.50
0.50
0.62

0.71
0.27
0.28
0.40
0.40
0.89
0.90
aPrices first quarter 1981.
            4-18

-------
financial resources that would have occurred anyway.  Substitution might
require the transition to come about sooner, but it is not likely to be the
only cause.
     The majority of traffic paints are based on alkyd resin systems.
Solvents typically used include aromatics, esters, and alcohols.  Chlorinated
solvents account for only nine percent of total consumption.  Substitution
for halogenated solvents in traffic paints appears to be reasonable from
the standpoint of costs.  The only costs would be due to reformulation and
these are expected to be small because review and evaluation is an ongoing
process.
                                     4-19

-------
4.5  REFERENCES
 1.  Huber, J.E., ed.  The Kline Guide to the Paint Industry.   Fairfield,  NJ.
     Charles H. Kline and Co., Inc. 1978.  p. 28-47.

 2.  Martens, C.R.  Pigments, Paints, Varnishes, Lacquers  and  Printing Inks.
     In:  Reigel's Handbook of Industrial Chemistry.   J.A.  Kent,  ed.   New
     York, Van Nostrand Reinhold Co.   1974.   p.  653-666.

 3.  Personal Communication.   E.  Anderson, GCA Corporation  with J.  Zacharias,
     National Paint and Coating Association,  Washington,  DC.   October 10,  1981.

 4.  McCartin, T., Materials  Balance  for Methyl  Chloroform,  JRB Associates,
     McLean, VA.   January 1980.

 5.  EPA Research Request No. 8.   Use No. 15:  Solvents  in  Paints and Allied
     Products.  Summary of Level  III  Study Results.

 6.  Personal Communication.   E.  Anderson, GCA Corporation  with R.  Johnson,
     Duplicolor Products Inc., Elk Grove Village,  IL.  November 19,  1981.

 7.  Personal Communication.   E.  Anderson, GCA Corporation  with G.  Kass,
     Krylon Department, Border Chemical  Co.,  Columbus, OH.   November  23, 1981.

 8.  McCartin, T., Materials  Balance  for Methylene  Chloride, JRB  Associates,
     McLean, VA.   January, 1980.

 9.  Ford, G.F.  A New Decade.  Aerosol  Age 26(7):23.  July  1981.

10.  Personal Communication.   E.  Anderson, GCA Corporation  with D.  Dahm,
     Illinois Bronze Paint Co., Chicago, IL.   December 1, 1981.

11.  Downing, R.C.   Theory and Practice  of Aerosols.   In:   Aerosols:   Science
     and Technology.   H.R. Shepard, ed.   New  York,  NY.   Interscience  Publishers,
     Inc.   1961.

12.  Garden, J.L. and J.P. Teas.   Solubility  Parameters.  Treatise  on Coatings
     Volume 2, Part II:   Characterization of  Coatings:   Physical  Techniques.
     R.R.  Myers and J.S. Long.  New York, NY.  Marcel Dekker.   1976.

13.  Chem Central Physical Properties  of Common  Organic  Solvents  and  Chemicals.
     1980.

14.  EPA Research Request No.  8.   Use  No.  15.  Solvents  in  Paints and Allied
     Products.  Summary of Level  II Study Results.


                                   4-20

-------
 15.  Sanders, P.A.  Principles of Aerosol  Technology,  New York,  Van Nostrand
      Reinhold Company.   1979.

 16.  Personal Communication.   E.  Anderson, GCA Corporation with  G.  Leep,
      Seymour of Sycamore,  Sycamore,  IL,  December 4,  1981.

 17.  Sausaman, O.K.   A  Practical  Approach  to Solvent Applications  in  Coatings
      and Inks.  Solvents  Theory and  Practice.   R.W.  Tess,  ed.  Washington,  DC.
      American Chemical  Society.  1973.

 18.  EPA Research Request  No.  8.   Use  No.  15;   Solvents  in Paints  and Allied
      Products.  Summary of Level  II  Study  Results.

 19.  Personal Communication.   E.  Anderson, GCA Corporation with  P   McKenna
      Plasti-Kote, Medina,  OH.   October 15, 1981.

 20.  Personal Communication.   E.  Anderson, GCA Corporation with  J.  Adkins,
      Baltimore Paint, Baltimore,  MD, November  20, 1981.

 21.  Personal Communication.   E.  Anderson,  GCA Corporation  with  F.  Smith,
      Ennis  Paint Manufacturing  Company,  Enm's,  TX.,  November 24, 1981.

 22.  Personal Communication.   E.  Anderson,  GCA Corporation  with  D.  Cooper,
      Prismo  Universal,  November 24, 1981.

 23.  Chatto,  D.R.  et al.   Development of Specifications of  Hot and  Cold
      Applied  Traffic Paints.  Sacramento,  CA.   California  State Department of
      Transportation.  September 1975.

 24.   Personal  Communication.  E. Anderson, GCA  Corporation with J.  Zacharias,
      National  Paint and Coating Association, Washington, DC.  October 22, 1981

 25.   Personal  Communications.   H. Rollins, GCA  Corporation with D. Rosse,
      U.S. Department of Commerce, Washington, DC.  December 17, 1981.

 26.   U.S. Department of Commerce.  1981  U.S. Industrial Outlook.   U.S
      Government Printing Office.  Washington, DC.  January 1981.   p. l'55.

 27.   U.S. Environmental  Protection Agency.   Development Document  for Effluent
      Limitations Guidelines and Standards for the Paint Formulating Point
      Source Category.   Washington, DC.   Publication  No. EPA-440/l-79/049b
      December  1979.

28.   Reference 26, p.  156.

29.   Personal Communication.  H. Rollins, GCA Corporation  with  H. Rhudy
     North Carolina Department  of Transportation, Raleigh,  North  Carolina
     December 17, 1981.

30.  Personal Communication.  E.  Anderson,  GCA  Corporation  with J.  Marchbank,
     bherwin Williams, Spray-on Division.   November  24,  1981.


                                  4-21

-------
31.  Personal Communication.   E.  Anderson,  GCA Corporation  with  Bartlep,
     Rustoleum, Chicago,  IL,  December 8,  1981.

32.  Personal Communication.   E.  Anderson,  GCA Corporation  with  G.  Kunz,
     Sherwin Williams,  Cleveland, OH, November 24,  1981.

33.  Personal Communication.   E.  Anderson,  GCA Corporation  with  F.  Smith,
     Emmis Paint Manufacturing Company,  Ennis,  TX,  December 11,  1981.

34.  Chemical Marketing Reporter, Schnell Publishing  Company,  New York, NY.
     March 31, 1981.
                                4-22

-------
                             5.0  FABRIC SCOURING

5.1  GENERAL DESCRIPTION OF USE
5.1.1  Process Description
     Fabric scouring is used to remove foreign substances remaining on
textile fibers or picked up during production of the fabric.  Fabric
scouring can be performed by either of two methods:  aqueous scouring or
solvent scouring.
     Aqueous scouring of fabric may be accomplished in batch or continuous
processes, with continuous scouring being the process more frequently
used.   In one continuous open-width fabric scouring process, the fabric
dips into a tank containing detergent and then passes through a pneumatically
loaded nip to ensure thorough penetration of the liquor into the fabric.
It is then plaited down into a tank containing wash liquor.  The fabric
sinks through the liquor and is drawn from the bottom of the pile by
rollers through opening scroll  rolls and a centralizing device onto an
endless mesh belt onto which it is held by suction boxes situated under
the belt.  While on the belt the fabric is subjected to high pressure
sprays of rinsing liquor.   The suction boxes draw the rinse liquor
through the fabric, removing most before it leaves the belt at which
                                                 p
point the fabric is given a final  light pressing.
     Scouring of textile materials with solvents has been done commercially
for several years.  There are two solvent processes for scouring textiles:
the batch process and the continuous process.   Batch solvent processing
machines have a system for heating the liquor and four to six tanks for
clean solvent,  rinse liquors and finish liquors.   The fabric is contained
in a perforated drum that rotates  in the solvent which is being circulated
through the drum.   The solvent  liquors are removed from the fabric by
centrifuging.   Fabrics are dried by hot air circulation,  and solvent is
                                    5-1

-------
 recovered  by  condensation and carbon adsorption.  Contaminated solvent
 is  cleaned by distillation.   Continuous solvent scouring occurs in a
 machine  similar to the one depicted in  Figure 5-1.  Fabric is fed on
 rollers  to the solvent scouring unit.   Here the fabric can be dipped or
 sprayed  with  cold solvent, or immersed  in hot vaporous solvent.  The
 fabric is  generally supported and tensionless when it is scoured.
 Following  the scouring process it is wrung and fed to the drying operation.
 Following  drying, the fabric may be folded, rolled, or sent to a dyeing
         4
 process.
     Solvent  scouring is used mostly for the cleaning of synthetic knit
 goods prior to finishing.  In knit synthetic fabrics, the primary impurities
 removed  are knitting and coning oils applied to the yarn to facilitate
 knitting.  Solvents are highly effective in removing these oils but
 typically  do  not remove many of the chemicals that are employed in the
 preparation of woven goods.  Thus, solvent scouring is generally limited
 to  the knit fabric segment of the textile industry.
     Perch!oroethylene is the solvent most frequently used in solvent
 scouring.  Trichloroethylene is also used, and recently trichlorotrifluoro-
 ethane (CFC-113) has come into use.  '6  The extent to which these other
 solvents are  used is not known.
 5.2  DESCRIPTION OF SUBSTITUTES
     Substitutes for trichloroethylene, perchloroethylene and CFC-113 in
 fabric scouring can be considered as two categories:   organic solvent
 substitutes and aqueous-based substitutes.   The organic solvent substitutes
 can be substituted directly for trichloroethylene,  perchloroethylene, and
 CFC-113  in the solvent scouring  process.  The aqueous-based substitutes are
 used in an aqueous scouring process  which can be substituted for the solvent
 scouring process.
     Organic solvents  that have  been reported to be used in fabric  scouring
 include benzene,  xylenes,  petroleum  solvents,  and 1,1-dichloroethylene.7'8
Although these solvents  have  been identified as  substitute solvents, none
are presently known to be  used in fabric scouring.9'10  Consequently,  no
 information concerning the technical  and economical  feasibility of  these
solvents as substitutes  was  obtained.

                                     5-2

-------
  FABRIC
   FEED
  SOLVENT
SCOURING UNIT
PAD
   DRYING AND
SOLVENT RECOVERY
 FABRIC
DELIVERY
               Figure 5-1.   Continuous  solvent scouring range.

      Aqueous-based substitutes to solvent scouring are aqueous scouring
 treatments using alkali  reagents  and anionic surfactants or nonionic
 surfactants to remove impurities  on  the  fabric.11   Aqueous scouring is
 currently used in the textile  industry for scouring of fabrics.
 5.3  TECHNICAL ANALYSIS  OF  SUBSTITUTES
      This section analyzes  the method  of substituting  aqueous  scouring
 for scouring  with perchloroethylene, the degree  to which aqueous  systems
 can be  substituted  for solvent scouring,  and the availability  of  equipment
 and materials  required to convert  to aqueous scouring.   This section only
 discusses the  feasibility of substituting  aqueous  scouring for scouring
 with  perchloroethylene,  since  perchloroethylene  is the  halogenated  solvent
 used  most often.  Although  only the substitution of aqueous scouring for
 solvent scouring  with perchloroethylene  is discussed,  the  information
 presented generally applies to the substitution  of aqueous  scouring systems
 using trichloroethylene  and CFC-113.   CFC-113 does  have  certain advantages
 over  perchloroethylene.  Its high volatility permits the solvent  to be
 completely  removed from  stripped knitting oil so the oil can be used as a
 fuel or recycled  to the  knitting step.  No information is  available on the
 technical  feasibility of other potential  organic solvent substitutes.
Also, the discussion in this section is based on the continuous scouring
 process since there is insufficient information available to evaluate
substitution using batch  processing operations.
                                    5-3

-------
5.3.1  Method of Substitution
     The substitution of aqueous scouring for solvent scouring necessitates
equipment replacement.  The equipment to be replaced is dependent on the
processes to which the fabric will be subject after scouring.  In solvent
scouring, the fabric leaves the process dry, while after aqueous scouring
the fabric is wet.  When the next step in the processing of the fabric
is aqueous processing, as in the dyeing process, the wet fabric coming
from the aqueous scourer need not be dried.  In this case the solvent
scouring range would be replaced only by a machine designed for aqueous
scouring.  However, if the fabric needs to be dry for the next process,
as in fabric printing, or if scouring is the last process in the finishing
of the fabric, which may be the case for yarn dyed goods, then in addition
to substituting the aqueous scourer for solvent scouring equipment, a
                        1 o
dryer needs to be added.
5.3.2  Degree of Substitution
     The degree to which aqueous scouring can be substituted for solvent
scouring depends on its effectiveness in removing knitting oils from the
cloth and the effect that substitution has on the processing rate.
Knitting oils applied to lubricate synthetic yarn to facilitate knitting
are the primary substances to be removed from synthetic knit fabric.
Table 5-1 shows examples of oil  removal  effectiveness of CFC-113 for
various types of fabrics.  Residual  oil  levels of 0.05-0.10 percent
generally can be achieved.   Scouring of polyester fabrics with perchloro-
ethylene with an initial oil  content of 4 percent has resulted in residual
oil contents 0.05 to 0.3 percent.
     Aqueous scouring is generally less  effective in removing oils.
Aqueous scouring using alkali  reagents removes oils by the formation of
soap with free fatty acids or by the decomposition of oils with the
formation of soap as part of the reaction.  The soap then behaves as an
emulsifying agent and removes  those substances on which the alkali  has
                   14
no chemical  action.    Aqueous scouring  on the average results in residual
oil concentrations of 0.3 to 0.4 percent by weight.
                                   5-4

-------
                            TABLE  5-1.   EXAMPLES OF OIL REMOVAL EFFICIENCIES FOR CFC-1136
tn
i
tn
Fabric
100% Polyester Jersey Crimplene
100% Polyester Single Knit
100% Texturized Polyester Double Knit
100% Texturized Polyester Double Knit, Yarn Dyed
100% Polyester Double Knit, Processed in Tubular Form
60/40 Type 54 Dacron Polyester Fiber/Type 66 Hyl.cn Kni.t
100% Type 66 Nylon Knit
100% Qiana Knit, Texturized Yarn
100% Polyester Woven Goods, Type 54 Spun Dacron Face;
Type 242 Spun Dacron Back
100% Polyester Woven -- Spun Yarn Warp, Texturized Yarn Fill
20/80 Polyester/Wool Woven
% Oil
Before
2.40
2.90
1.60
1.00
2.20
0.35
5.40
4.30

2.20
0.40
2.30
on fabric
After
0.05
0.05
0.05
0.05
0.10
0.05
0.20
0.10

0.10
0.10
0.20

-------
     While aqueous scouring does not have oil  removal  effectiveness
                                                                    915
equivalent to that of solvent scouring, it performs an adequate job.  '
Higher residual  oil  in a fabric may make the fabric resistant to dye  or
print paste, but levels under 0.5 percent typically do not cause significant
         1 ? 1 *i
problems.       DuPont has commented, however, that this level  is subjective,
and does not apply across-the-board.  Lower residual  oil levels are
beneficial when fabric is heat set.  The lower oil  residue reduces yellowing
and oil "mist" thus  helping to maintain occupational  standards.  While
aqueous systems are  not as effective as solvent scourers in removing
knitting oils, they  are more versatile.  Aqueous systems can remove
impurities in cotton that solvents cannot, and thus can be used for
scouring cotton-synthetic blends as well as 100 percent synthetics.
     Aqueous scourers can generally achieve process rates comparable  to those
of solvent scourers.  Thus, in the case where  drying  of the aqueous  scoured
fabric is not necessary, substitution of aqueous systems for solvent  would
not have an impact on processing time.  In the case where the aqueous
scoured fabric must  be dried prior to the next process step, the effect
that the addition of this step would have on production time would depend
on the number of shifts per day that the plant operates.  Typical  drying
time is about one hour, so plants operating one eight-hour shift daily
would suffer a 12.5  percent decrease in daily  production of fabric;  plants
operating two shifts per day would experience  a 6.3 percent decrease  in
daily production; while plants operating at three shifts per day (essentially
a continuous operation) would not experience any appreciable decrease in daily
production.
5.3.3  Resource Availability
     The technical feasibility of substituting aqueous scouring for  solvent
scouring depends upon the resource availability of aqueous scouring machines.
To determine the resource availability of aqueous scouring machines,  13 manu-
facturers and dealers of scouring machines were contacted.    Of these
13 manufacturers and dealers, 3 responded and  each stated that  their  company
could produce about  50 aqueous scouring machines per  year for a total of at
                            17 18 19
least 150 machines per year.  '  '    There are approximately 214 scouring
                                       20
and bleaching ranges in knitting mills.    Since 3 manufacturers can
make 150 aqueous scouring machines annually, it is assumed that the
                                      5-6

-------
 other nine  manufacturers  can  make  enough  aqueous  scouring machines,
 i.e., about 64  machines annually,  to  replace all  existing solvent scouring
 machines  at knit  fabric mills.   The resource availability of aqueous
 scourers  appears  to  be adequate  and does  not appear to be a constraint
 to  substituting aqueous scouring machines for solvent scouring machines.
 5.4  ECONOMIC ANALYSIS OF SUBSTITUTES
      For  purposes of this study, the economic feasiblity of solvent
 substitutes in  fabric scouring deals only with describing and estimating
 the relevant costs.   Two  cost categories are analyzed:  costs associated
 with a decline  in product quality, where the decline is attributable to
 substitution; and capital and annualized operating costs.  No attempt is
 made to assess  the user's ability to pay these costs.
 5.4.1  Industry Structure
      Knit fabric mills, where most solvent scouring applications are
 found, is a  subsector of  the textile industry.   Trends and projections
 for knit fabric mills are presented in Table 5-2.20  The majority of the
 fabric industry is located in North Carolina, South Carolina, and Georgia.
 In  1980, more than half of all fabric industry employment was located in
 these states.
      EPA estimates that approximately 1,973 of the 7,200 mills (27.4 percent)
 involved in  the production of textile goods utilize wet processing.   Of
 these, approximately 282 finish knit fabric.   A breakdown of production
 capacities and  a geographic distribution of wet processing mills is
                            ?i
 shown in Tables 5-3 and 5-4.
 5.4.2  Market Penetration of Substitutes
     A survey conducted by the U.S. Department  of Commerce indicates
 that in 1978, 899 scouring and bleaching ranges were in place in the
 textile industry,  of which 214 were in knitting mills.20  Data to indicate
 the breakdown of solvent-based versus  water based machines in knitting
mills is not available.   Consequently, the market penetration of aqueous
machines has not been determined  in this analysis.
                                       5-7

-------
                          TABLE  5-2.   KNIT FABRIC  MILLS:  .TRENDS AND  PROJECTIONS  1975-8020
                                         (in millions of current dollars except as noted)
Item
Industry (SIC 2257-58)
Value of shipments1
Value added
Valued added per production worker-hour ($)
Total employment (000)
Production workers (000)
Average hourly earnings (Dec.--$)
Year-to-year percent change In average
hourly earnings (Dec. -Dec.)
Capital expenditures
Product (SIC 2257-2258)
Value of shipments5

-------
TABLE 5-3.  GEOGRAPHICAL DISTRIBUTION OF WET PROCESSING TEXTILE MILLS^1
Manufacturing
Segment
Wool scouring
Wool finishing
Low water use
processing
h'oven fabric
finishing
Knit fabric
finishing
Hosiery
finishing
Carpet
finishing
Stock & yarn
finishing
Nonwoven
manufacturing
Felted fabric
processing
All segments

I
6
20

86

69

27

2

0

33

10

7
260

II
1
2

108

54

58

2

1

19

3

2
250

III
3
4

125

34

45

9

4

31

4

3
262
EPA
IV
3
3

463

155

134

139

39

120

11

3
1,070
Region
V
0
1

11

11

9

5

1

6

7

2
53
VI
3
1

8

3

1

2

4

3

2

0
27
VII
0
1

1

1

2

0

0

1

0

0
6
VIII
0
1

0

2

0

0

0

0

0

0
3
IX
0
0

4

.7

6

0

9

4

1

3
34
X
1
4

2

0

0

1

0

0

0

0
8
All
regions
17
37

808

336

282

160

58

217

38

20
1,973
                                5-9

-------
TABLE 5-4.  PRODUCTION CAPACITY OF WET PROCESSING MILLS21
Manufacturing
segment
Wool scouring
Wool finishing
Low water use
processing
Woven fabric
finishing
Knit fabric
finishing
Hosiery finishing
Carpet finishing
• Stock & yarn
o finishing
Nonwoven
manufacturing
Felted fabric
processing
All segments
Mills within given production
0-2
2
8

10

36

43
94
2

32

3

6
236
2-4
3
9

7

27

26
25
2

47

3

5
154
4-9
0
9

11

33

34
10
7

35

2

2
143
9-13
1
2

19

28

29
5
3

23

4

1
115
13-22
4
1

23

33

48
2
8

25

3

0
147
22-34
2
2

21

21

21
0
5

20

5

0
97
range,
34-45
2
2

7

20

7
0
6

6

2

0
52
Mg/day
45-68
2
0

5

12

9
0
7

7

2

•1
45

68-91
0
0

3

9

5
0
5

1

0

0
23

91+
0
0

2

21

1
0
5

2

1

0
32
Un-
known
1
4

700

96

59
24
8

19

13

5
929
All
mills
17
37

808

336

282
160
58

217

38

20
1,973

-------
 5.4.3  Growth Trends
      Within the past five years,  the synthetic knit fabric industry has
 suffered a severe decline in  output.   Consequently, a concomitant  decrease
 in the use of solvent scouring  has  been  experienced.   In addition,  the
 shift from 100 percent synthetic  to synthetic/cotton  blends  has  decreased
 the use of solvent scouring since solvents  cannot adequately remove
 impurities in cotton and  thus are not typically used  in  the  scouring of
        5
 blends.    Major manufacturers and dealers of  solvent  scouring machines
 are no longer carrying them nor have  they sold any in the past few
                              tal
                              15
      1 15 23-27
years. '  '       One dealer stated that only one third of the units
 that  he  sold  still  are  in use.
 5.4.4 Product  Quality
      Product  quality  in fabric scouring relates  to  the degree of cleanliness
 achieved  in a given process.  The Technical Analysis Section reports
 that  aqueous  scouring results in residual oil concentrations of 0.3 to
 0.4 percent.  Industry representatives generally do not believe the
 reduced effectiveness of an aqueous system causes significant problems,
 since fabrics are only resistant to dye and print paste at levels greater
 than  0.5  percent.    Consequently, though product quality may decline,
 no costs  are associated with it.
 5.4.5  Capital  and Annualized Costs of Substitution
     This section estimates capital and annualized costs directly attributable
 to substitution.  Capital  costs include the expense of any new equipment
 and the expense of installing and making it operational.   Capital  costs
 are particularly relevant  in assessing the economic feasibility of
 converting an existing solvent scouring operation to one using and
 aqueous systems, since this  conversion would necessitate a change  in
 equipment.
     Annualized  costs  are  estimated for both aqueous and  solvent systems
 for model  plant  operations.   Comparison of these costs  shows  the additional
cost burden attributable to  substitution which will  recur annually.
                                      5-11

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5.4.5.1  Model Plant Parameters
     A model plant for knit fabric finishing with an annual throughput
                               21
of 5,600 megagrams (6,160 tons)   and an operating schedule of three
shifts per day, seven days per week and fifty weeks per year was used in
calculating annual operating costs.  A product mix of 25 percent light
weight knits, 50 percent medium weight knits, 25 percent heavy weight
knits (average 0.22 kg per meter)  with a width of 1.5 meters was assumed.
Operating costs were compared for  two cases:  for scouring conducted
prior to a wet processing step where the aqueous scoured fabric does not
need to be dried, and for scouring conducted prior to a dry processing
step where the aqueous scoured fabric needs to be dried.
5.4.5.2  Capital Costs
     Capital costs for aqueous scouring equipment and drying equipment
are presented in Table 5-5.  Equipment costs are estimates obtained from
manufacturers and dealers.  Taxes, freight and instrumentation are
treated as a single component and  calculated at 18 percent of equipment
      2<
     30
      29
costs.    Installation costs are estimated at 10 percent of equipment
cost.
5.4.5.3  Annualized Costs
     Annualized costs for aqueous and perchloroethylene fabric scouring
                                                                          28 30 31
are based on information supplied by a manufacturer of scouring equipment.
Cost estimates for perchloroethylene scouring are based on performance
                             28
claims made by manufacturers.     Costs estimates for aqueous scouring
are based on actual annualized costs incurred by a textile processing
mill from their use of a continuous, open width washer for scouring knit
fabrics.    Annualized costs of drying equipment are estimates obtained
                         32
from an equipment dealer.    The annualized costs are shown in Tables 5-6
and 5-7.
     In Case 1, shown in Table 5-6,  where aqueous scouring is not followed
by drying, the annual costs of aqueous scouring are 14 percent higher
than those for solvent scouring.  While steam and electricity costs are
lower for aqueous scouring by 54 and 60 percent respectively, the costs
of chemicals, process water, and wastewater treatment are 4 times the
cost of solvent and cooling water in solvent scouring.
                                    5-12

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    TABLE 5-5.  CAPITAL COSTS FOR CONTINUOUS AQUEOUS SCOURING FACILITY
Aqueous scouring not followed by drying
     Aqueous scouring range3                             251,000
     Taxes, freight, instrumentation                      45,200
     Installation0                                        25,100
     Total                                               321,300
Aqueous scouring followed by drying
     Aqueous scouring range3                             251,000
     Dryerd                                              140,000
     Taxes, freight, instrumentation                      70,400
     Installation0                                        39,100
     Total                                               500,500

References 11 and 33.
 Equals 18 percent of equipment cost.   Reference 29.
°Equals 10 percent of equipment cost.   Reference 30.
 References 32 and 34.
                                    5-13

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       TABLE 5-6.  COMPARATIVE ANNUALIZED COSTS OF CONTINUOUS AQUEOUS
                   AND SOLVENT SCOURING
                                     Perch!oroethylene
                                         scouring
                    Aqueous
                   scouring
Case 1:  Aqueous scouring not
         followed by drying.

Operating costs

  Steam                                  285,000
  Electricity                             49,400
  Cooling water                            8,640
  Solvent                                 79,700
  Process water
  Chemicals
  Wastewater treatment
  Labor
  Maintenance
  Administration, insurance, & taxes

    Subtotal                             422,740

Capital recovery8                         57,130

Total                                    479,870
                   130,000
                    19,800
                    17,300
                   320,000
                    22,000
assumed equivalent
                   509,100

                    37,700C

                   546,800
 Capital recovery factor is based on a 20 year life and 10 percent interest
 rate.
 Capital recovery is based on an existing solvent scouring machine with an
 installed capital  cost of $486,400.   Reference 35.
cCapital recovery is based on an aqueous scouring machine with an installed
 capital cost of $321,000 (see Table 5-5).
                                    5-14

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        TABLE 5-7.  COMPARATIVE ANNUALIZED COSTS OF CONTINUOUS AQUEOUS
                    AND SOLVENT SCOURING
                                     Perchloroethylene
                                         scouring
 Aqueous
scouring
Case 2:  Aqueous scouring
         followed by drying.

Operating costs
Scourer
Steam
Electricity
Cooling water
Solvent
Process water
Chemicals
Wastewater treatment
Labor
Maintenance
Administration, insurance & taxes
Subtotal
Dryer
Steam
Electricity
Labor
Subtotal
Capital recovery3
Total
aCapital recovery factor is based on a
rate.

285,000
49,400
8,640
79,700
--
--
--

assumed

422,740

--
--
--
--
57,130b

479,870
20 year life and


130,000
19,800
--
--
17,300
320,000
22,000

equivalent

509,100

377,000
18,500
35,600
431,100
58,800°

999,000
10 percent interest

 Capital  recovery  is  based  on an  existing  solvent  scouring machine with an
 installed  capital  cost  of  $486,400.  Reference  35.

 Capital  recovery  is  based  on an  aqueous scouring  machine with an installed
 capital  cost  of $500,500 (see Table 5-5).
                                    5-15

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      In Case 2, shown in Table 5-7, where aqueous scouring is followed
by drying, annual costs of a facility using aqueous scouring are approximately
twice those for solvent scouring.
                                                                        '§)
      DuPont incorporated by reference annual operating costs of Permaso'i  F
versus perch!oroethylene and aqueous scouring.  According to DuPont's
calculations, annual operating costs for aqueous systems, perch!oroethylene
                     ®
systems, and Permaso!  F systems are $202,000, $177,000, and $99,000
respectively (see Appendix A).
5.5   CONCLUSIONS
      Perchloroethylene is the solvent most frequently used in solvent
scouring.  Trichloroethylene is also used and recently CFC-113 has come
into  use.  Several other organic solvents, such as benzene, xylenes,
petroleum solvents, and 1,1-dichloroethylene have been reported as potential
substitute solvents for perchloroethylene, trichloroethylene and CFC-113
in solvent scouring.  However, none of these potential substitute solvents
is presently known to be used in fabric scouring, and information concerning
their technical and economic feasibility as substitute solvents is not
available.
     A currently used substitute for solvent scouring is aqueous scouring
using solution containing alkali reagents and anionic or nonionic surfactants.
Aqueous scouring does not remove knitting oils from the fabric as well as
solvent scouring; however,  aqueous scouring performs an adequate job and
is more versatile since aqueous systems can remove impurities in cotton and
cotton-synthetic blends that solvent scouring cannot remove.   The availability
of aqueous scouring machines appears to be adequate to substitute aqueous
scourers for solvent scourers.  Aqueous fabric scouring appears to be a
technically feasible substitute to solvent scouring using halogenated
solvents.
     Based on the model  plant estimates used to develop economic analysis
information, substituting aqueous scouring for solvent scouring would cause
an increase in the annualized operating cost of fabric scouring depending
on whether the aqueous scourer is followed by a dryer.  When  the solvent
scourer is replaced by an aqueous scourer, the annualized cost increases
                                    5-16

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only 14 percent; however, when the solvent scourer is  replaced  by  an  aqueous
scourer and dryer, the annual!zed cost increases  by about  100 percent.   The
economic feasibility of substituting aqueous scouring  for  solvent  scouring
would depend upon whether a dryer was needed with aqueous  scouring machine
and the ability of the plant to incur the increase in  the  annualized  cost.
                                    5-17

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 5.6  REFERENCES


 1.  Personal Communication.   E.  Anderson,  GCA Corporation  with  R.  Eby,
     Keiltex Corporation,  Charlotte,  NC.   December 4,  1981.

 2.  Haigh, D.  The Preparation Processes.   In:   Dyeing and Finishing  Knitted
     Goods.  Leicester, England,  Hosiery  Trade Journal.

 3.  Perkins, Warren S.  Textile  Solvent  Processing:   A Literature  Survey,
     Water Resources Research Institute,  Auburn  University,  Auburn,  Alabama,
     May 1976.

 4.  Hofstetter, Hans,  H.   Solvent Processing for Textiles,  W.R.C.  Smith
     Publishing Company, Atlanta, Georgia,  June  1970.

 5.  Personal Communication.   E.  Anderson,  GCA Corporation  with  C.  Livingood,
     Dept. of Textile Chemistry,  North Carolina  State  University.   November  13,  1981

 6.  Bell, D.G.  "New Chemical  Solvent Opens  Ways for  Safe,  Energy-Conscious
     Textile Scouring".  Modern Knitting  Management 57:32-34,  May/June  1979.

 7.  Hoogheem, T.J., et al.   Source Assessment:   Solvent Evaporation -  Degreasing
     Operations, Contract  No.  68-02-1874,  U.S. Environmental  Protection Agency,
     Cincinnati, Ohio,  June  1978.

 8.  Matthews, J.C., et al.   Screening Study  on  Justification  of Developing  New
     Source Performance Standards for Various Textile  Processing Operations,
     Contract No.  68-02-0607-11,  U.S. Environmental  Protection Agency,
     Research Triangle  Park,  North Carolina,  August 1974.

 9.  Personal Communication.   E.  Anderson,  GCA Corporation  with  B.  Walter,
     American Permac Inc.,  Plainview, NY.   December 10, 1981.

10.  Personal Communication.   E.  Anderson,  GCA Corporation  with  N.  Stuart,
     Institute of Textile  Technology.  Charlottesville, VA.   December  9,  1981.

11.  Oyabu, N.  Desizing and  Scouring of  Synthetic Fibers.   Japan Textile
     News 269:  33-34.   April  1977.

12.  Personal Communication.   E.  Anderson,  GCA Corporation  with  R.  Ramsey,
     E.I. du Pont de Nemours  and  Company,  Wilmington,  DE.   December  3,  1981.

13.  Kolb, K.  "Practical  Experience  with  the Continuous Solvent Scouring
     Machine for Knit Goods."   Textile Solvent Technology -  Update  '73.
     American Association  of  Textile  Chemists and Colorists.   Research
     Triangle Park,  NC.  1973.   pp. 91-96.


                                      5-18

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14.   Marsh, J.T.   Textile  Science,  Champman  and  Hall  Ltd.,  London,  England,
     1949.

15.   Personal  Communication.   E.  Anderson, GCA Corporation  with  B.  Falk,  ITM,
     Ltd.,  December 10,  1981.

16.   Davison's Textile Blue  Book, 114th  Edition,  Davison's  Publishing Co.,
     Ridgewood, NJ, 1980.   p.  566.

17.   Personal  Communication.   E.  Anderson, GCA Corporation  with  C.  Tie,
     Mega  Marketing, Inc., Boonton, N.J.   December  29,  1981.

18.   Personal  Communication.   E.  Anderson, GCA Corporation  with  M.  Koledo,
     Briggs and Lambard, Springfield,  VT.  December 29,  1981.

19.   Personal  Communication.   E.  Anderson, GCA Corporation, with M.  Hazen,
     Morrison  Textile Machinery Co., Ft.  Lawn, SC.   December  29, 1981.

20.   U.S.  Department of Commerce.  Chapter 34:   Textiles.   In:   Industrial
     Outlook.   U.S. Government Printing  Office.   Washington,  DC.  January 1981.

21.   U.S.  Environmental  Protection  Agency.   Development  Document for Effluent
     Guidelines and Standards  for the  Textile Mills Point Source Category.
     Washington, DC.  Publication No.  EPA-440/l-79/022-b.   October 1979.

22.   U.S.  Department of Commerce.  1977  Census of Manufacturers:  Textile
     Machinery in Place.  Washington,  DC.  1980.

23.   Personal  Communication.   E.  Anderson, GCA Corporation  with  W.  Holmes,
     Riggs and Lombard,  Inc.,  Lowell,  MA.  November 18,  1981.

24.   Personal  Communication.   E.  Anderson, GCA Corporation  with  B.  Lyttle,
     Brian Lyttle, December 9, 1981.

25.   Personal  Communication.   E.  Anderson, GCA Corporation  with  Tekmatex,
     Inc., Charlotte, NC.   November 18,  1981.

26.   Personal  Communication.   E.  Anderson, GCA Corporation  with  H.  Williams,
     Bruckner Machinery Corporation, Spartanburg, SC.   November  18,  1981.

27.   Personal  Communication.   E.  Anderson, GCA Corporation  with  D.  Sangster,
     Schmidt Manufacturing Corporation,  Greensboro, NC.   December 9, 1981.

28.   Ramsey, R.B.  Fabric Scouring with  Trichlorotrifluoroethane.  Presented
     at the National Technical Conference of American Association of Textile
     Chemists  and Colorists.   October 1979.

29.   United States Environmental  Protection  Agency.  Petroleum Dry
     Cleaners  - Background Information for Proposed Standards (Preliminary
     Draft).  Office of Air Quality Planning and Standards.   Research Triangle
     Park, NC.  November 1981.
                                       5-19

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30.  Personal Communication.   E.  Anderson,  GCA Corporation  with  R.  Mantry,
     Textile Machinery,  Charlotte,  NC.  December 7,  1981.

31.  Letter with enclosures.   R.B.  Ramsey,  E.I.  du  Pont  de  Nemours  and  Company
     to E. Anderson, GCA Corporation.   December 7,  1981.

32.  Personal Communication.   E.  Anderson,  GCA Corporation  with  P.  Krafton,  .
     Consolidated Engineering, Atlanta,  GA.   December  17, 1981.

33.  Personal Communication.   E.  Anderson,  GCA Corporation  with  T.  Spantinato,
     Textile Machinery,  Charlotte,  NC,  December 17,  1981.

34.  Personal Communication.   E.  Anderson,  GCA Corporation  with  D.  Forman,
     Fab-Con Machinery,  Development Corporation,  Port  Washington, NY,
     December 7, 1981.

35.  Personal Communication.   E.  Anderson,  GCA Corporation  with  T.  Spantinato,
     Textile Machinery,  Charlotte,  NC,  December 4,  1981.
                                   5-20

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                  APPENDIX A





Comments by E.I.  du Pont de Nemours & Company
                        A-l

-------
           3PIŁ
E. I. DU PONT DE NEMOURS & COMPANY

    WILMINGTON. DELAWARE 19898

PETROCHEMICALS DEPARTMENT                  November 5, 1962
     Ks.  Virginia  K.  Steiner
     Task Manager
     U.S. Environmental  Protection  Agency
     Office  of  Pesticides  and  Toxic Substances
     Waterside  Mall
     401  M Street, S.W.
     Washington, D.C.  20460

     Dear Ms. Steiner:


          COMMENTS ON THE  DRAFT  FINAL  REPORT  FROM GCA CORPORATION
       TO EPA ENTITLED "PRELIMINARY ANALYSIS  OF POSSIBLE  SUBSTITUTES
               FOR 1,1,1-TRICHLOROETHANE,  TETRACHLOROETHENE,
          DICHLOROMETHANE, TETRACHLOROMETHANE,  TRICHLOROETHENE,  AND
         TRICHLOROTRIFLUOROETHANE," DATED  MAY 1982 (GCA-TR-82-46-G)
              The Du  Pont  Company wishes to provide the following
     comments on the  subject Draft Analysis.  Our comments specifi-
     cally apply to trichlorotrifluoroethane (CFC-113).  I have
     arranged our comments into Sections as follows:

              1.  GENERAL  COMMENTS
              2.  SPECIFIC ADVANTAGEOUS PROPERTIES OF CFC-113
                    SOLVENTS
              3.  SPECIFIC COMMENTS ON SOURCE CATEGORIES (END-USES)
              4.  REFERENCES
                                  A-2

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                               -2-
Reference is frequently made to the subject Draft Analysis and
such references are shown in square brackets, for instance
[p. 1-5] refers to page 1-5 in the Draft Analysis.  References
cited in these comments are shown in parenthesis as (HAS, 1979)
                             Yours sincere
                             RichardB. Ward
                             Research Associate
                             Freon* Products Division
RBW:plt

Attachment

CC:  Richard Rehm
     GCA Corporation
     GCA/Technology Division
     Chapel Bill, NC  27514
                               A-3

-------
     COMMENTS ON THE DRAFT FINAL REPORT FROM GCA CORPORATION
  TO EPA ENTITLED "PRELIMINARY ANALYSIS OF POSSIBLE SUBSTITUTES
          FOR 1,1,1-TRICHLOROETHANE, TETRACHLOROETHENE,
     DICHLOROMETHANE. TETRACHLOROMETHANE, TRICHLOROETHENE, AND
    TRICHLOROTRIFLUOROETBANE," DATED MAY 1982 (GCA-TR-82-46-G)
1.  GENERAL COMMENTS

         The Draft Analysis is specifically limited to four
source
categories or end-uses [p. iii]:
         Metal Cleaning (which in the Analysis includes cleaning
of printed circuit board assemblies)

         Dry Cleaning

         Surface Coatings  (in which CFC use is insignificant and
therefore is not further addressed in these comments), and

         Fabric Scouring

Other solvent uses are omitted from the Analysis and  from these
comments.

         The report provides a good outline of the  uses covered
and of alternative technologies.  However, in discussing the uses
involving CFC-113, the Analysis does not  include a  discussion  of
the unique properties of CFC-113  in most  of its solvent applica-
tions.  It is with regard  to discussion of such properties  that
we recommend thorough revision.

         The unique properties of CFC-113 (see Section 2 of these
Comments) not only justify the use of this more expensive sol-
vent, but also materially  increase  the difficulty  in  finding
alternatives to CFC-113.   For most uses,  economics  would force
substitution of cheaper solvents  (such as the  other chlorinated
                              A-4

-------
solvents) if process effectiveness,  safety,  and product quality
and reliability could be maintained at necessary levels.  Thus it

follows that CFC-113 tends to be used only in those applications

where nothing else will do the job adequately.


         It is this critical evaluation of the adequacy of alter-

natives for CFC-113 that is almost totally omitted in this
Analysis.  Although the Analysis correctly notes (p. iiij:


              "...halogenated solvents...are often used
              because their physical and chemical pro-
              perties make them unique in given
              situations,"

              "...it should be noted that substitution
              may not always be feasible," and

              •[Substitution] should always  be
              determined on a case-by-case basis,"

These  statements  are not applied  to  the discussion of  CFC-113.


         Under Metal Cleaning  [p. 2-16] it is  noted  that:


               "...there are  areas where complete sub-
               stitution may  be  infeasible and  halo-
               genated  solvents  must  be used."

 A careful  evaluation would  show  this to be particularly true  in

 CFC-113  use,  particularly  in  applications  in which several
 materials  of  construction  are  cleaned  simultaneously — such  as

 in electronics assemblies.


          In dry cleaning  and  fabric  scouring,  essentially no
 attempt  is made  to  distinguish  CFC-113 from  tetrachloroethylene.


          We note* that it is only in references to aerosol

 formulations of  paints and in Section 5 (Fabric Scouring)
 *The copy of the report we received contained no pages 3-29 or
  3-30 and thus did not show references 1 to 14 inclusive in
  Section 3.  The text does not suggest any of the missing
  references would materially alter this observation.
                               A-5

-------
that any indication is made that Du Pont sources of information
have been consulted.  Even in the Fabric Scouring section the
report incorrectly assumes [p. 5-3]:

              •Although only the substitution of
              aqueous scouring for solvent scouring
              with perchloroethylene is discussed, the
              information presented generally applies
              to the substitution of aqueous scouring
              [for] systems using...CFC-113."
This is contrary to the information in the cited reference
(Ramsey, 1979).  [Reference 28, p. 5-18].

         Equally surprising is the apparent absence of any ref-
erence to previous analyses of alternatives to CFC-113, such as
by the National Academy of Sciences (NAS, 1979) or the Rand
Corporation (Rand, 1982), in which both the unique properties of
CFC-113, and the importance of these properties in discussing
alternatives to CFC-113, were better recognized.  The opportunity
for this Analysis  to build on such earlier reports and the
comments prepared  on these earlier reports (e.g., Du Pont, 1980;
Ward, 1981, 1982)  has been overlooked.

2.  SPECIFIC ADVANTAGEOUS PROPERTIES OF CFC-113 SOLVENT

         CFC-113 finds most of its applications due to its unique
combination of properties.  The most obvious are  its very low
toxicity, nonflammability, inertness,  and volatility.  The low
toxicity provides  a major safety  advantage for workers.

         While the advantages of  nonflammability  are obvious and
are acknowledged in  the  Analysis  [p. 1-6], they  are omitted  in
economic estimates of alternatives  [p.  3-28].   In certain situa-
tions,  fire codes  may forbid  storage and  use of  flammable sol-
vents no matter what  retrofitting is undertaken.   An example
might be a city neighborhood  dry  cleaner  at  street  level  in  a
multistory, multiple  use  building.

                              A-6

-------
         The inertness of CFC-113 provides several important
advantages.  The inherent stability in use removes the  need for
chemical stabilizers, simplifying recycle since stablizers may be
fractionated by distillation or removed when solvent is separated
from water contamination.  The mild solvent properties  of CFC-113
result in a very broad range of materials being compatible with
the solvent, an essential asset when, for example, multiple
plastics are found in printed circuit assemblies or as  trim,
etc., on clothing.  While this advantage is hinted at [pp. 2-16,
2-19], it is overlooked elsewhere (pp. 1-5, 2-15, 2-17, 3-1,
5-1].

         A further advantage of the inertness of CFC-113 is that
the compound is negligibly photochemically reactive and therefore
CFC-113 emissions do not contribute to smog (EPA, 1980). Hydro-
carbon alternatives do not share this benefit, a point totally
overlooked  [e.g., at pp. 2-28, 3-7, 5-2].

         The volatility  (the compound has a low boiling point of
43°C and a low latent heat of evaporation, 35.07 cal/g) confers a
number of advantages.  Energy requirements to maintain boiling
liquid or vapor zones are minimized,  cleaned material can be
handled  immediately, solvent treated materials are  readily dried,
and the  convection currents, which tend  to increase vapor loss
from equipment containing boiling solvent, are minimized.  To an
extent,  CFC-113 has essentially an optimum boiling  point.  Advan-
tages from a lower boiling point  (e.g.,  CFC-11,  b.p. 24  C) are,
in fact, more  than offset by greater  difficulties  in containing
the more volatile solvent in most cases, hence the  preponderant
use in the U.S. of CFC-113 versus CFC-11 as a  solvent.   The
importance of  this advantageous volatility is  overlooked  [e.g.,
at pp. 1-5, 2-14, 2-15,  2-16,  2-27].

         Other physical  properties of CFC-113  used to  advantage
include  the high molecular weight  (187.5), high  liquid  density
                               A-7

-------
(1.565 g/cm  at 25°C),  low surface tension (17.3 dynes/cm at
25°C), and the formation of azeotropes with several more polar
volatile solvents.

         The high molecular weight results in a dense vapor
further aiding vapor recycle.   The high liquid density,  notice-
ably absent in hydrocarbons, aids in the ability of CFC-113 to
•float" off particulate contaminants from surfaces to be cleaned.

         The low surface tension aids in the wetting of  surfaces
and cleaning of small interstices.  This is particularly impor-
tant in comparison with aqueous cleaning alternatives but is not
adequately discussed in the Analysis [e.g., at pp. 1-5,  2-17].

         CFC-113 forms azeotropes* with a number of more polar
and volatile compounds such as methanol, ethanol, acetone, and
methylene chloride.  These azeotropes are nonflammable and permit
•fine-tuning" of the solvent properties for specific applica-
tions.  Almost half of CFC-113 solvent is sold as an azeotrope
— providing a clear example of the preciseness with which
CFC-113-based solvents are tailored for optimum performance in
specific applications.   Such azeotropes substantially extend the
value of CFC-113 in removing certain contaminants, soldering
fluxes, etc.  [cf.,  pp.  2-3, 2-8, 2-17].

         Further details of the properties of CFC-113 solvent,
azeotropes, and blends are given in the Du Pont Bulletin FS-21
(Du Pont, 1977).
*A mixture in which liquid and vapor phases have the same com-
 position and in which, therefore, components are not selectively
 concentrated during evaporation or at the boil.
                               A-8

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3.  SPECIFIC COMMENTS ON SOURCE CATEGORIES (END-USES)

3.1  Metal Cleaning

         Most applications of CFC-113 and its azeotropes and
blends are in the cleaning of products other than simple metal
parts.  It is, therefore, unfortunate that this section has been
labeled "Metal Cleaning."  Most CFC-113 cleaning applications are
for electronic, medical, and other equipment involving a variety
of materials of construction, intricate shapes including small
interstices and close-packed electronic assemblies, and where
extremely low levels of residues and soil are essential to the
product's end-use and reliability [pp. 1-5, 1-9, 2-1,  2-24].

         Separation of these "high technology" cleaning applica-
tions from conventional metal cleaning in two separate source
categories is recommended.  Such a revision would permit a
clearer differentiation between the categories in terms of
solvent property requirements and cleaning specifications, etc.

         Emulsion cleaning and abrasive blasting are wholly
inappropriate as alternatives for virtually all CFC-113 solvent
applications.  Water, unless doped with surfactants, has a high
surface tension  (72 dynes/cm versus 17.3 dynes/cm for CFC-113 at
25°C) and thus does not wet surfaces or penetrate interstices as
well.  Removal of surfactant residues represents a major techni-
cal difficulty with aqueous systems  (Ramsey, 1974, 1975; Keller,
1981).  Energy consumption at the consumer's plant is an impor-
tant factor, as are ecological concerns  (Ramsey, 1974,  1975;
Obrzut, 1977).  It should also be noted that solvent cleaning
processes concentrate soil and contaminants for appropriate dis-
posal, while aqueous processes disperse contaminants  [pp. 1-5,
2-15, 2-17].

         Many resins and  fluxes used in electronic component
assembly cannot be removed by aqueous cleaning.

                              A-9

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         The statement [p.  2-8]  that solvent degreasing is
•totally ineffective in the removal of...most miscellaneous
contaminants" is incorrect.   Such miscellaneous contaminants as
particulates, soil, fluxes, quenching oils and inorganic salts
are removed effectively by CFC-113-based solvents to the most
exacting specifications in space, medical, and communications
related applications.  (See Du Pont, 1977).

         Compatibility with materials of construction can be ex-
tremely critical.  Absorption of solvent can alter capacitance
values or physical dimensions, for instance, and evaporation of
the absorbed solvent may be slow ~ resulting in drifting perfor-
mance or changing tolerances in subsequent testing and use.  The
high compatibility of CFC-113 with materials of construction and
its low boiling point frequently make CFC-113 essential in criti-
cal applications involving the cleaning and drying of electronic,
electrical,  and mechanical assemblies (NAS, 1979, p. 157).  Apart
from flaramability concerns, substitution of aliphatic, aromatic,
or oxygenated solvents would not satisfy the precise solvent
requirement  for these exacting applications  [pp. 1-5, 2-24, et.
seq.].  Again the concept  of "metal cleaning" does not convey the
concept of high technology applications for which CFC-113 sol-
vents are principally used.

         The 65/35 weight  percent  blend of  CFC-113 with ethanol
is not an azeotrope  lp. 2-31).  The composition of the azeotrope
is approximately 96/4 weight percent  CFC-113/denatured ethanol
(e.g., Freon* TE Solvent,  Du Pont  1977).   The 65/35  blend  is
intended for cold cleaning or use  in  specially designed vapor
degreasers.  Although the  mixture  initially has no flash point
when brought to  the  boiling point,  evaporation can result  in  a
flammable residual solvent.   (See  Du  Pont,  1977,  Freon* TE-35
Solvent).
                                A-10

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         There are areas, particularly involving ordinary metal
cleaning, where aqueous cleaning and solvent cleaning are di-
rectly competitive.  It appears that examples of substitution of
aqueous techniques for solvent techniques have been selected
[pp. 2-16, 2-17),  since examples of the reverse substitution
exist but are not  discussed.  Aqueous cleaning has replaced
solvents in less exacting applications, where CFC-113 does not
find major, use.  For instance, a number of factors have combined
to reduce the proportionate use of trichloroethylene — a rela-
tively strong solvent.  As would be expected in a competitive
situation, the market share lost by trichloroethylene has been
divided mainly between other chlorinated solvents and aqueous
processing.  It certainly does not follow that most CFC-113
solvent uses can be similarly substituted by aqueous cleaning.

         CFC-113 is negligibly photochemically reactive (EPA,
1980) and does not contribute to photochemical smog.  Hydro-
carbon and oxygenated solvents act as precursors for smog and
adversely affect ambient air quality [p. 2-28].

         The data  in Tables 2-1 and 2-6 should be identified as
to year  [pp. 2-3,   2-38].

3.2  Dry Cleaning

         The most  significant factor which  is understated  is the
fire potential in  substituting to a hydrocarbon solvent.   As
pointed out  in Section 1 of these comments,  flammable solvents
may be prohibited  in many dry cleaning locations, requiring  total
relocation of  businesses converting to hydrocarbon  use.   It  is
unfortunate  that fire code  related costs are  omitted from the
cost estimates in  Tables 3-10,  3-11, and 3-12 [pp.  3-25,  3-26,
and 3-27].   The cost  comparison  for most dry  cleaning establish-
ments  is meaningless  with this  omission.
                               A-ll

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         This section also glosses over the advantages of CFC-113
in dry cleaning.  The inertness of the CFC-113 solvent make it
more compatible with plastic trim, buttons, etc., and of suede
and leather goods in the dry cleaning process, and can eliminate
the time-consuming necessity to remove such materials from
clothing prior to dry cleaning, and reattachment afterwards [p.
3-1].  The high volatility and low absorption of CFC-113 solvent
into fibers means that the drying step can be carried out under
milder conditions, an important factor for certain fabrics.  As a
result, CFC-113 finds special applications in the dry cleaning
industry and should not be equated with perchloroethylene in this
Analysis [pp. 1-6, 3-8].

         Hydrocarbon emissions act as precursors for smog, while
CFC-113 does not.  This is an important factor in maintaining
national ambient air standards for ozone in the urban
environment.

         The data in Table 3-4 should be identified as to year
and  referenced  [p. 3-15].

3.3  Fabric Scouring

         The importance of the unique properties of CFC-113 have
been overlooked in the Analysis.   An  important factor  is the ease
with which CFC-113 can be stripped from the knitting  oil.  Ramsey
 (1979) points out that the high volatility of CFC-113  permits  the
solvent  to be so completely  removed  from stripped  knitting oil
that this oil can be used as fuel  (for a fuel credit)  or even
recycled for use in  the knitting  step (for a  larger credit).   The
waste  disposal  costs of the  stripped  knitting oil  are  eliminated.
CFC-113  should  not be equated  to  perchloroethylene in this
Analysis  [pp. 1-6, 5-3].  .
                               A-12

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         The comment that 'residual oil levels under 0.5 percent
typically do not cause significant problems" is subjective,  and
does not apply accross-the-board.  Prior to the introduction of
CFC-113 scouring, the higher residual oil levels were accepted
because there was no other choice.  The lower residual oil levels
achieved with CFC-113 scouring have been particularly beneficial
when the fabric is subsequently heat set.  The lower oil residue
reduces yellowing from residual oil, and reduces oil "smoke" or
"mist" formation in this step.  This is important in the work-
place since a 5 mg/m3 8-hour Time Weighted Average (TWA) has been
established by the American Conference of Governmental Industrial
Hygienists for mineral oil mists.

         The economic analysis shown in Ramsey (1979) indicates
that the total costs in switching from CFC-113 scouring to a
water process would be substantially greater than the examples
shown in the Analysis Tables 5-6 and 5-7 tpp. 5-14, 5-15].
                               A-13

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4.  REFERENCES


*Du Pont Bulletin FS-21:  Du Pont Freon* Solvents That Meet
    Today's Cleaning Needs, 1977.

*Du Pont:  "Comments on the December 1979 Report by the National
    Academy of Sciences' Committee on Alternatives for the
    Reduction of Chlorofluorocarbon Emissions (CARCE)."
    Wilmington, DE,  1980.

 EPA, 45 Federal Register, 48941-2, July 22, 1980.

*Keller, J.,  Improving PWB Reliability While Cutting Soldering
    and Cleaning Costs.  Assembly Engineering, May 1981, pp.
    14-17 (Part 1);  June 1981, pp. 14-18 (Part 2); July 1981, pp.
    18-21 (Part 3).

 National Academy of Sciences:  Report of the Committee on Alter-
    natives for the  Reduction of Chlorofluorocarbon Emissions, in
    •Protection Against Depletion of Stratospheric Ozone by
    Chlorofluorocarbons."  Washington, D.C., 1979.

*0brzut, J. J., Metals Can be Cleaned With Less Energy, Iron Age,
    48-50, May 1977.

*Ramsey, R. B., Jr., Cleaning System Selection Under Today's
    Ecological and Safety Constraints.  Paper presented at
    Internepcon Europa, Brussels, Belgium, May 28, 1974.

*Ramsey, R. B., Jr., The Niche for Fluorinated Solvents.  Metal
    Progress, 71-74, April 1975.
'References so marked are enclosed,

                              A-14

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*Ramsey, R. B., Jr., Fabric Scouring with Trichlorotrifluoro-
    ethane.  Presented at the National Technical Conference,
    American Association of Textile Chemists and Colorists,
    October 1979.  (Du Pont Technical Report RP-10).

 Rand Corporation:  Technical Options for Reducing Chlorofluoro-
    carbon Emissions, Mooz, W. E., e_t _al.  Santa Monica, CA,
    March.1982.

*Ward, R. B. (Du Pont Company), letter/attachments to Mooz, W. E.
    (Rand Corporation):  •Comments on 'Preliminary Assessment of
    Chlorofluorocarbon Emission Reduction Methods, N-1734-EPA,'
    July 1981."  November 24, 1981.

*Ward, R. B. (Du Pont Company), letter/attachments to Clay, D. R,
    (EPA):  "Comments on 'Rand Report R-2879-EPA:  Technical
    Options for Reducing Chlorofluorocarbon Emissions'."
    July 13, 1982.
'References so marked are enclosed.

RBW:plt
                               A-15

                               -12-

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                       APPENDIX  B





Comments by the Halogenated Cleaning Solvents  Association
                             B-l

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                        Hologenoted Cleaning Solvents Association
                         c/o SOCMA. 1075 Central Partc Avenue. Scarsdale. New York 10583
                          Affiliated with Synthetic Organic Chemical Manulacturers Association. Inc.
                         January 6,  1983
Mr. Walter Kovalick, Jr.
Director, Integration  Staff
Office of Toxics  Integration
U.S. Environmental  Protection Agency
TS-777
401 M Street,  SW
Washington, DC 20460

          Re:  Draft Substitutes Analysis for
               the  Halogenated Solvents	

Dear Mr. Kovalick:

          We  are  pleased  to provide these comments  on the draft

preliminary analysis of possible substitutes for  1,1,1-tri-

chloroethane,  tetrachloroethylene, dichloromethane,  tetra-

chloromethane, trichloroethylene, and trichlorotrifluoroethane

(May 1982) prepared by GCA Corporation.

          As  you  know, HCSA is concerned that  EPA has under-

taken regulatory  initiatives to control emissions of these sol-

vents to the  atmosphere in the absence of sound scientific evi-

dence that  such  emissions endanger human health or  the environ-

ment at  ambient  concentrations.  The Science Advisory Board

review of draft  health assessments for the  solvents should be

the starting  point for any determination of whether regulation

of emissions  of  these  solvents is warranted.   We recognize that

the Office  of Toxics  Integration  can play an  important role in

                                B-2

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 coordinating EPA's overall approach  to  these  solvents, once the




 evaluation  of  their health effects is completed.   In  this



 regard,  should it be demonstrated that  exposure  to halogenated




 solvents poses a  significant  risk to human  health, it would be



 necessary to evaluate  alternatives to such  solvents  in terms  of




 the  overall risk  to human health and the environment  posed by



 such alternatives.  In the absence of such  an evaluation, it



 should not  be  assumed  that control of the halogenated solvents



 would reduce overall risk to  human health or the environment.



          The  comments below  are technical  in nature. No




 attempt has been  made  to confirm quantitative data appearing  in




 the  analysis.   These comments are  offered in a spirit of



 cooperation to achieve a technically accurate document.



 However, as indicated  above,  we believe that it is premature  to



 examine substitutes  to the halogenated  cleaning solvents in the




 absence of scientifically sound reasons to believe that current




 or expected environmental concentrations of such solvents pose




 any significant health or environmental risk.






                         METAL CLEANING



            1.    Table 2-1 indicates  quantities of  solvents much




 greater  than  those which are being  consumed  currently.  Based




 on historical  sales data, it may be estimated that total sales




 of halogenated solvents to metal cleaning  operations in 1982




-will  be  approximately  60 to 65 percent of  those shown in this




 table.





                               B-3

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           2.   Some additional parameters  important  in the




 selection  of a cleaning process include:   factory  floor space



 available, water availability, waste water treatment availabi-



 lity,  regulations, ventilation requirements,  energy  con-



 sumption,  and waste disposal.  These criteria for  process



 selection  could be inserted  into  the text  on  page  2-6.



           3.   Neither organic solvents  nor alkaline washing



 compounds  solubilize  the  abrasives  contained  in pigmented  draw-



 ing  compounds, buffing compounds, etc.   Solvent degreasing with



 spraying or  ultrasonic agitation  can remove these  contaminants



 when the media carrying  the  abrasives  are  solvent  soluble.



 When the media are water soluble  or soluble in alkaline  solu-



 tions (soaps,  for  example) aqueous  cleaning can be effective.



 The  suggestion on  page 2-8 that halogenated solvents are not



 useful cleaning  agents for all  such compounds is incorrect.



           4.   As  stated on  page  2-11,  it is  not possible as  a



 general matter  to  convert vapor  degreasing equipment into



 aqueous cleaning equipment.   It  should also be noted that the



 space required  for an alkaline cleaning system frequently will



 be much greater  than that required  for a  solvent cleaning sys-



 tem.  Tables 2-9,  2-10,  and  2-11  show user energy costs for



 alkaline washing that are substantially greater than those for



 vapor degreasing.   Therefore, increased steam generating capac-



 ity may need to be installed or alternative  gas or  electric



Cheating may be required.  The heat and moisture from the washer
                               B-4

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as well as the parts drying section of the washer will need to

be exhausted from the operating area.  These exhaust rates are

often so substantial that plant heating costs can be signifi-

cantly affected in the winter, and air conditioning may be

impractical even in plants in the southern United States.

Increased health risks from heat stress, potential skin or eye

injury from alkaline salts or salt solution concentrates, and

risks associated with water pollution should be evaluated rela-

tive to any risks defined for the halogenated solvent cleaning

system which would be replaced.

          5.   The following quote appears on page 2-15:

          Results of the study have shown that under
          identical operating conditions and work-
          loads, aqueous cleaning of printed circuit
          boards can be done up to six times more
          effectively than similar solvent-based sys-
          tems .

This statement is supported by a reference from Jim Dingman,

Unique Industries, Inc., Sun Valley, California.  Art Gillman,

President of Unique Industries, has indicated that Mr. Dingman

is not an employee of Unique  Industries but  is a sales repre-

sentative for  that firm.  Mr. Dingman requested  the opportunity

to review any  quotations of his conversation before release  and

has not granted any release.  Further, he reports  that the

statement made was taken out  of context.  See attached letter

from Mr. A. Gillman, President, Unique  Industries.

          Two  articles on printed  circuit board  cleaning are

attached.  Attention is  called to  the  cleaning  system


                              B-5

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performance chart on page 2 of the article "Are Aqueous Systems

the 'Universal' Solution?".  The results and conclusions of the

paper entitled "Organic Surface Contamination — Its

Identification, Characterization, Removal, Effects on

Insulation Resistance and Conformal Coating Adhesion" are also

of particular interest.

          6.   The statement on page 2-15 concerning "Ct]he

traditionally low cost of halogenated solvents due to compara-

tively inexpensive petroleum feed stocks and energy sources" is

misleading.  The halogenated solvents are made from petroleum

feed stocks by the use of chemical process steps, energy, chlo-

rine and, in the case of CFC-113, hydrogen fluoride.

Consequently, their  cost will  always be  several  times the cost

of petroleum solvents.  Aqueous  cleaning  compounds, on  the

other hand, are based largely  on  caustic  (sodium hydroxide).

Alkaline  cleaning solutions are,  and have  always been,  cheaper

than the  equivalent  quantity of  halogenated  solvents.

           7.   The  first complete sentence on  page  2-16 would

more appropriately  be  reworded as follows:

           Regulatory pressures had  not  influenced  the
           selection of  a metal cleaning  process  until
           recently.  Solvent  cleaning,  aqueous clean-
           ing, and  other cleaning processes  were cho-
           sen  solely on their  engineer-ing merit.
           Listings,  regulations,  and guidelines,
           which  have been  proposed or adopted  in many
           cases  with inadequate scientific justifica-
           tion,  have increasingly discouraged  the use
           of  halogenated  solvents.
                               B-6

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           8.   With reference to  section  2.3.1, aqueous systems

 are  likely to  leave residual water on parts  cleaned, particu-

 larly  in  recesses.  This  frequently occurs even in  systems

 equipped  with  a  dryer  stage.  The retained moisture can induce

 corrosion.  When aqueous  cleaning solutions  must  have  a strong

 alkalinity (pH 10 or greater) to  achieve  effective  cleaning,

 chemical  attack  on aluminum  and other reactive metals  can be

 expected.

           9.   On pages  2-17 and  2-18,  some  of the  advantages

 of combining  organic solvent cleaning with  aqueous  cleaning  in

 emulsion  systems are discussed.   However, the text  fails  to

 describe  adequately the  fact that emulsion  cleaners also

 inherit the disadvantages of both systems.   Emulsion cleaning

 liquids,  being largely comprised  of  water,  are unsuitable for

 electronic parts or electrical  assemblies cleaning.  As  an

 aqueous system,  emulsion cleaning generally requires more space

 and as much or nearly  as much  energy as alkaline washing,  par-

 ticularly if the parts require  drying,  as is common.  Both

 alkaline washing and  emulsion  cleaning have much higher user

 energy demands than are common in solvent cleaning operations.

 Although emulsion cleaning does provide  some ability to solubi-

 lize solvent soluble  soils compared with aqueous systems, this

 method of compounding  does not increase  the solvency of the

 solvent  employed above that of the pure  solvent.   Since the
^-
 solvent  portion of the emulsion  is a relatively  small
                               B-7

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percentage, the ability to dissolve solvent soluble soils




before saturating the emulsion cleaner is highly limited.




Solvent emulsion systems are not recoverable by distillation,




contribute to water pollution, and present a substantial waste




disposal burden due to their low load carrying ability for




soil.



          The literature reports that the best cleaning is




obtained with the least stable emulsions.  In such emulsion



cleaning systems, a separate phase of solvent frequently will



be formed.  Solvents employed in emulsion cleaning typically




have flash points and pose some fire hazard.  Emulsified sol-




vents will display a vapor pressure and will, therefore, eva-



porate from the emulsion to some extent.  As in the case of



aqueous cleaning, high ventilation rates are experienced both



in the washing stages and drying stages of emulsion cleaners.



Therefore, it is unlikely that high concentrations of the sol-




vent vapors will exist in the work atmosphere.  Emulsion sys-




tems without ventilation and with higher temperatures employed



must be regarded as sources of possible solvent vapor expo-




sures.  Although the emissions of hydrocarbon solvents  from



emulsion systems have been ignored in the draft analysis, there




is no doubt that these hydrocarbon vapors contribute to  ambient




ozone concentration and may result in adverse health effects




due to smog formation.
                              B-8

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          10.   With regard to section 2.3.3,  abrasive or non-




chejnical cleaning of metal parts does not represent any signif-



icant alternative to solvent cleaning.  This process substan-




tially modifies the surface in many cases, is labor intensive,




and can pose health risks from dust and, in some cases, direct




injury by impingement on skin.



          11.   The evaluation of other organic solvents to




replace the halogenated solvents cannot be considered complete




unless the total health effects of the replacement are weighed




against those of the compound being replaced.  Aside from the




cost comparison between the substitute solvent and the



halogenated solvent, the health risks associated with the sub-



stitutes, including  flammability, toxicity, and contribution  to




ambient ozone, must  be evaluated.  The consideration given to



CFC-11  in section  2.3.4 as  a  potential  replacement  for  CFC-113



must be questioned when the sole  justification  for  replacing




CFC-113 is  its unproven hypothetical  effect  on  stratospheric




ozone  and the  chlorine contribution  of  CFC-11  is  equal to or



greater than that  of CFC-113  on an  equal weight basis.   It



should be noted  that ozone  depletion estimates  are theoretical




in nature and  ozone  depletion has not been detected by actual




measurements.  Although  it  may be possible from an engineering




standpoint  to  control  solvent losses of CFC-11  from degreasing




operations,  it must be recognized that a solvent which




essentially boils  at room temperature will be difficult to
                              B-9

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contain and this difficulty will be compounded in warmer




climates and high altitude locations.



          12.  In conclusion,  it is common to find all varie-




ties of metal cleaning processes in diversified metal manufac-



turing plants.  The choices of metal cleaning processes for



these plants have been made by trained engineering and purchas-



ing professionals and are based on favorable economic, energy,




safety, and performance considerations.  In spite of the pre-



sent regulatory focus on halogenated solvent emissions, such



solvents continue to be widely employed due to their recognized



value.  Alternatives to the halogenated solvents can be appro-




priately explored only after an evaluation of the health and



environmental risks associated with each of the suggested



alternatives.  Use of any alternatives to halogenated solvents




without full appraisal of the relative risks of both systems



cannot be assumed to result in an overall reduction of risk to




workers or the public.






                         DRY CLEANING




          The statement on page 3-1  that  "Perchloroethylene  is




nonflammable  .  .  . and is comparable to petroleum  solvents in




price"  should be  changed to "...  . and is competitive with




petroleum solvents on a performance  or production  basis."




Although the price per kilogram for  both  solvents  is  roughly




competitive, the  cost per gallon  for perchloroethylene  is  two



times  or more greater than that for  petroleum solvents  given  on




page  3-23.                    B_10

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          The only alternative to halogenated solvent dry

cleaning proposed in the analysis is petroleum solvent dry

cleaning.  The comparison of these processes in the draft ana-

lysis illustrates the danger of failing to evaluate the total

risks associated with alternatives.  One would assume from the

draft analysis that the substitution of petroleum solvent for

perchloroethylene in dry cleaning would substantially reduce

the total risk experienced both by the general public and oper-

ating personnel.  This conclusion is suggested in spite of the

fact that the dry cleaning industry historically used petroleum

solvent  and has been in the process of converting to perchloro-

ethylene over a period of about 50 years.  That this trend con-

tinues  is supported by the statement, on page  3-13, that  "One

company  .  •  • reported that an order  for a petroleum washer had

not been received in two years."   It  is  common in this  industry

for one  or  more members of the proprietor's  family  to  operate

the dry cleaning  equipment.   Therefore,  it  is  reasonable  to

expect  that these proprietors have great concern  for  the  wel-

fare  of dry cleaning operators  and would only  convert  to  a

safer  system from one  which  poses greater  danger.   The far

greater relative  fire  hazard  of petroleum solvents  compared to

perchloroethylene is  recognized in hundreds of municipal  fire

 codes throughout  the  country.

           Dry cleaning businesses tend to be located in
^
 buildings  with other  commercial establishments or in buildings
                               B-ll

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 with apartment  dwellings.   In  such  cases,  the  solvent  must  be

 transported  through  densely populated  areas  from bulk

 inventories  to  the dry  cleaner.   Therefore,  the fire hazard

 associated with petroleum  dry  cleaning is  not  limited  to the

 dry cleaning business  itself.   The  text reports 11,800 to

 18,000 coin-operated dry cleaning businesses and notes that

 they would be prevented from converting to petroleum solvents

 by fire protection  codes.   Even if  permissible, this conversion

 would be impractical in most cases  due to space considerations.

 Thus, the statement  on page 3-12 	 "When all of the  above

 factors are  considered, petroleum solvents are shown to be a

 complete substitute  for perc"  	 is certainly not true for

 coin-operated dry cleaning businesses.

           Similarly, the report notes that some commercial dry

 cleaning businesses  could not physically adapt to petroleum

 solvent dry cleaning or would be prevented from doing so by

 fire codes.   A large portion of dry cleaning businesses lease

 building space and may justifiably be reluctant to make

 building improvements to meet fire codes when  they do not  own

 the building.  As stated on page 3-28,  "This would  leave the

 proprietor with the option of finding new space or  going out of

 business."  In the  first instance,  the  cost of operation would

 go  up  substantially because the proprietor would  need to

 maintain a  store-front dry cleaning business to retain  his cus-
s
 tomers while relocating his dry  cleaning  facility in  another
                               B-12

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acceptable location.  Neither of the options stated on page



3-28 for existing perchloroethylene dry cleaners required to



convert to petroleum solvents supports the conclusion that



petroleum dry cleaning is "a complete substitute for perc."



          The toxicology of perchloroethylene has been extensi-



vely tested.  No summation of the toxicology of petroleum sol-



vents is presented or referenced.



          The adverse health effects of ozone are the basis for



a national ambient air quality standard.  In a draft report



entitled "Photochemical Reactivity of Perchloroethylene"



(October 1982), EPA concludes that perchloroethylene is less



photochemically reactive than ethane.  If this conclusion is



confirmed after public review of the draft report, EPA will



have no justification for requiring regulation of perchloro-



ethylene as an ozone precursor.  On the other hand, it is gen-



erally recognized that the petroleum solvents contribute to



ambient ozone.  Moreover, uncontrolled emissions from petroleum



solvent dry cleaning operations are eight times those from per-



chloroethylene dry  cleaning operations on a gallon basis  (page



3-23).



          With regard to the economic comparisons, several



observations  are in order.  A reasonable economic  return  could



have been expected  on an investment of $29,000  for perchloro-



ethylene dry  cleaning equipment  several years  ago  at  an
sS


interest rate of less than  10 percent per annum.   However,
                              B-13

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retiring that perchloroethylene equipment now and reinvesting




approximately $46,000 for petroleum cleaning equipment at a




probable interest rate considerably above 10 percent is likely




to be much less attractive, particularly when combined with



increased operating costs.  The cost scenarios in the draft



analysis for converting from perchloroethylene to petroleum



solvents do not examine the investments needed for rewiring,



fire walls, and boiler modifications to provide an explosion-



resistant facility.  No costs are associated with fire detec-




tion or fire extinguishing equipment.  Further, a scenario  for




relocating the petroleum dry cleaning machinery away from pop-



ulated areas while maintaining a dry cleaning storefront in  the



old location to preserve customer loyalty needs to be consid-



ered, as the failure of a  large number of small businesses




would be expected  in such  circumstances.



          There are a number of other deficiencies in the anal-




ysis of the economic effects of conversion  from perchloroethy-




lene to petroleum  solvent  dry  cleaning.   It is questionable



that the useful  life of petroleum solvent dry  cleaning  equip-



ment is thirty years unless technological advances are  disre-




garded  and  it  is assumed  that  plant  operators, due to  the  lower




cost of petroleum  solvents, have grown  unconcerned about sol-




vent leakage and losses.   Even if this  equipment  lifetime  were,




realistic,  we  question whether a typical operator would accept




a return of capital  over  a thirty-year  period.   It  does not
                              B-14

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seem probable that the maintenance costs for a petroleum



solvent dry cleaning system could remain as low as such costs



for a perchloroethylene dry cleaning system, due to the differ-




ence in the original capital costs and to the longer expected




life of the petroleum dry cleaning equipment.  The overhead




costs for both types of operations are described on page 3-24



as being equal to 4 percent of the equipment costs.  However,



the annual cost comparisons in tables 3-10, 3-11, and 3-12 show




the overhead to be the same for both perchloroethylene plants




and petroleum plants.  This appears to be inconsistent.



Finally, it would be expected that the insurance costs for



petroleum dry cleaning would be greater because of the




increased fire hazard due to the use of flammable solvents and




the value of the equipment.






                       SURFACE COATINGS




          Nearly all paints were once formulated with petroleum




hydrocarbon solvents.  Such solvents contribute to ambient




ozone formation.  As previously noted, EPA  has determined that




the formation of ozone in the ambient atmosphere  is  adverse  to




human health and has responded to this problem by  limiting




emissions of anthropogenic hydrocarbon solvents.  Much of the




interest in methylene chloride and methyl  chloroform, which  are




negligibly photochemically reactive, has been  stimulated by




"regulations to control ozone precursors.
                               B-15

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          The replacement of halogenated solvents with petro-



leum solvents in paint formulation is not necessarily a simple



matter and would not take place in an otherwise unregulated



business area.  Reformulation to petroleum solvent paint sys-



tems would, in some cases, also require changes in the resins



and/or pigmentation of the paints.  In turn, these changes



might require alteration or replacement of various portions of



the paint handling or application equipment.  In order to



maintain compliance with ambient ozone regulations, even more



extensive compromises and changes might be required.  The



unlimited emission of hydrocarbon solvents is not permissible



under today's ozone regulations.  Therefore, the installation



of incineration equipment with or without heat recovery may be



required.  Carbon adsorption could also be regarded as an



alternative in controlling the hydrocarbon solvent losses to



the atmosphere.  Both of these emission control devices are



unreasonably expensive for many kinds of painting operations.



Overall operating costs would most frequently be higher where



the halogenated solvents were replaced by petroleum solvents.



Moreover, it is unlikely that the use of certain petroleum sol-



vents, such as acetone, would reduce the cost of paint per gal-



lon.  In other instances, where cheaper solvents were employed,



the cost per gallon might not be reduced due to changes in the



resin or pigmentation needed to obtain parallel performance



properties.
                              B-16

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           Many potential  solvent substitutes are more toxic



 than methylene chloride and 1,1,1-trichloroethane.




 Essentially,  all  of the alternative solvents would  pose greatly



 increased fire risks.   In the  discussion of possible substi-




 tutes for halogenated  solvents  in coatings, no data are presen-



 ted  which would indicate  that  the alternatives are  as safe from




 a  fire hazard standpoint  or pose  less  acute or chronic toxic



 hazard to workers  or the  general  public.   While it  might be




 concluded that petroleum-based  paints  can be formulated to pro-



 vide roughly  equivalent gloss,  adhesion,  rheology,  drying char-



 acteristics,  weatherability, etc.,  as  those formulated with



 halogenated solvents,  it  must be  questioned whether these prop-



 erties  can be obtained  simultaneously  in  existing equipment



 without increased  costs and without  greater fire  or envi-



 ronmental  risk  or  endangerment  to public  health.




           In  addition to  the above properties,  halogenated  sol-



 vents offer formability,  chip resistance,  rapid color  change,




 cold  temperature stability, air drying capability,  nonflammabi-




 lity, and the  use  of standard paint  application equipment,  com-



bined with nil  contribution to ambient ozone.   All  of  these




properties cannot be achieved in formulations  using petroleum



solvents.




          It  is unlikely that halogenated  solvents will ever




attain a major  share of the coatings marketplace  currently held




by petroleum  solvent-based paints.  Most of the petroleum-base
                              B-17

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coating applications will convert to waterborne, powder, or 100




percent solid systems where possible.  However, these new




painting technologies cannot satisfy all of the coatings



requirements.  Estimates of the potential use of methylene



chloride or 1,1,1-trichloroethane as future potential




replacements for petroleum hydrocarbons have ranged from 5 to



10 percent.  These solvents are used as a primary carrier with-



out loss of application or coating performance  characteristics.



The technology exists to prevent substantial losses of  solvent



during application.  As industry use of these solvents  becomes




more sophisticated, air drying operations, ovens with reduced




ventilation rates and/or other solvent recovery techniques




offer a considerable reduction in energy requirements.



          Foremost among the attributes of methylene chloride



and 1,1,1-trichloroethane in coatings operations are the redu-




ced fire hazard and compliance with  ozone regulations without




exceedingly high capital and operating costs.   The draft anal-




ysis contains no comparison of the total environmental  and



health risks of solvent alternatives for paint  formulation with




the two halogenated solvent systems.  We are confident  that



when the human health and environmental risks  and benefits of



methylene  chloride  and 1,1,1-trichloroethane are weighed




against those of feasible alternatives, the advantages  of  these




halogenated  solvents will be obvious.
                              B-18

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                         FABRIC  SCOURING




           Textile processes  such as dyeing,  finishing,  and




 scouring  have  been  dominated by aqueous processes over  the



 years.  Historically,  solvent processes in the textile  industry




 have  represented a  small minority of operations and have been




 used  in place  of the  customary  aqueous processes.  Certainly,



 if  this report had  been  written from the viewpoint of prevent-



 ing water pollution,  solvent scouring would have been one of



 the proposed substitutes.  From an energy standpoint, solvent




 scouring  is many times more  efficient when the fabric must be




 dried.  Assuming an equal  weight of water and perchloroethylene




 are left  on fabric, the  water will require 10.8 times more




 energy for drying than the perchloroethylene.  If equal volumes



 of  water  and perchloroethylene  are left on fabric,  6.66 times




 more  energy is required  for  the water.  Since the industry has



 an  obvious preference  for  aqueous processes,  it is fair to




 assume that solvent processes are selected only after careful



 consideration.  However,  the draft analysis does not examine



 the special performance  characteristics, costs, space consider-




 ations, energy limitations,  and other factors which are impor-




 tant  considerations in choosing a solvent scouring process.






                           CONCLUSION




           The  analysis of  alternatives cannot be complete with-




-out i) an analysis  of  the  human health and environmental risks




 associated with halogenated  solvent usage; and ii)  an analysis






                              B-19

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of the human health and environmental risks associated with the

use of alternatives.  The former is under way and will probably

be completed in 1983.  The present document should be revised

to incorporate the latter so that a comparison of risks may be

made if it should be determined that present or expected envi-

ronmental concentrations of the halogenated cleaning solvents

pose any significant risk to human health or the environment.

          Should a comparison of relative risks favor the use

of an alternative to a halogenated cleaning solvent in any par-

ticular operation or process, the relative performances and

overall cost of replacement, including capital investment

needed, energy usage, water pollution, operating costs, and

other factors, should be weighed against the expected benefits

or reductions in risk.

                         Respectfully submitted,

                         HALOGENATED CLEANING SOLVENTS ASSOCIATION
                         Alan W. Rautio
                         Executive Director
Attachments
cc:  Mr. Richard M. Rehm
                             B-20

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