United States
Environmental Protection
Agency
Office of Air Quality
Planning and Standards
Research Triangle Park NC 27711
EPA-450/3-89-030
August 1989
Air
<>EPA
Alternative Control
Technology Document
Halogenated Solvent
Cleaners
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EPA-450/3-89-030
Alternative Control
Technology Document
Halogenated Solvent
Cleaners
Emissions Standards Division
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air and Radiation
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
August 1989
tJ.S.
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ALTERNATIVE CONTROL TECHNOLOGY DOCUMENTS
This report is issued by the Emission Standards Division, Office
of Air Quality Planning and Standards, U.S. Environmental
Protection Agency, to provide information to state and local air
pollution control agencies. Mention of trade names or commercial
products is not intended to constitute endorsement or
recommendation for use. Copies of this report are available - as
supplies permit - from the Library Services Office (MD-35), U.S.
Environmental Protection Agency, Research Triangle Park, North
Carolina 27711, or for a nominal fee, from the National Technical
Information Service, 5285 Port Royal Road, Springfield, Virginia
22161.
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TABLE OF CONTENTS
Section Page
1.0 INTRODUCTION 1-1
2.0 SUMMARY 2-1
3.0 ORGANIC SOLVENT CLEANER CHARACTERISTICS AND EMISSIONS .... 3-1
3.1 General 3-1
3.2 Organic Solvent Cleaning Processes 3-2
3.2.1 Open Top Vapor Cleaners 3-3
3.2.2 In-line Cleaners 3-13
3.2.3 Hybrid Cleaners 3-20
3.2.4 Cold Cleaners 3-23
3.3 Emission Mechanisms and Types 3-25
3.3.1 Air/Solvent Vapor Interface Losses during
Idling (Idling Losses) 3-26
3.3.2 Workload Related Losses (Workload Losses) .... 3-32
3.3.3 Other Losses 3-40
3.4 Typical Emission Scenarios for Vapor Cleaners 3-44
3.5 References 3-48
4.0 EMISSION CONTROL TECHNIQUES 4-1
4.1 Introduction 4-1
4.2 Open Top Vapor Cleaners 4-1
4.2.1 Controls for Interface Emissions 4-7
4.2.2 Controls for Workload Emissions 4-35
4.2.3 Proper Operating and Maintenance Practices. . . . 4-40
4.3 In-line Cleaners 4-47
4.3.1 Controls for Interface Emissions 4-49
4.3.2 Control for Workload Emissions 4-52
4.3.3 Proper Operating and Maintenance Practices. . . . 4-56
4.4 Cold Cleaners 4-59
4.5 Integrated Control Strategies 4-60
4.5.1 Summary of Solvent Loss Reduction Techniques. . . 4-60
4.5.2 Effective Control Technique Combinations 4-64
4.6 Alternative Cleaning Agents 4-66
4.7 References 4-71
5.0 COST ANALYSIS
5.1 Introduction 5-1
5.2 Costing Methodology 5-2
5.2.1 Model Cleaner Approach 5-3
5.2.2 Capital Costs 5-4
5.2.3 Annual Operating Costs 5-9
m
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TABLE OF CONTENTS
Section
5.3 Open Top Vapor Cleaners 5-10
5.3.1 Model Cleaner Parameters 5-10
5.3.2 Model OTVC Cost Evaluation 5-14
5.4 In-line Cleaners 5-25
5.4.1 Model Cleaner Parameters 5-25
5.4.2 Cost Evaluation 5-29
5.5 References 5.35
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LIST OF TABLES
Number Page
3-1 Summary of Available Tests - Idling OTVC's 3-29
3-2 Summary of Emission Tests on Working OTVC's 3-36
3-3 Halogenated Solvent Evaporation Rates 3-41
3-4 Example of Operating Schedule Influence on Solvent
Cleaner Emissions 3-47
4-1 Summary of Solvent Cleaner Control Techniques 4-2
4-2 Summary of Available Tests - Idling OTVC's 4-4
4-3 Summary of Available Tests 0 Working OTVC's 4-5
2
4-4 Solvent Loss Rate Versus Spraying Practices (Ib/ft /hr)
Ten 40 Second Cycles per Hour Gensolv/D, 24 Inch Freeboard. . 4-41
4-5 Summary of Available Tests - In-line Cleaners 4-48
4-6 Available Control Techniques for OTVC Operations 4-61
4-7 Available Control Techniques for In-Line Operations 4-62
4-8 Available Control Techniques for Cold Cleaners 4-63
4-9 Effectiveness of Selected OTVC Control Technique
Combinations 4-65
4-10 Effectiveness of Selected In-line Cleaner Control Technique
Combinations 4-67
5-1 Capital Costs (1988) Used in Cost Analysis 5-5
5-2 Summary of Operating Cost Parameters 5-11
5-3 Model Cleaner Parameters for Open Top Vapor Cleaners 5-15
5-4 Summary of Retrofit Control Costs and Cost Effectiveness for
Model OTVC's Using Methylene Chloride (1988 $) 5-19
5-5 Summary of Retrofit Control Costs and Cost Effectiveness for
Model OTVC's Using Perchloroethylene (1988 $) 5-20
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LIST OF TABLES (Continued)
Number Page
5-6 Summary of Retrofit Control Costs and Cost Effectiveness
for Model OTVC's using Trichloroethylene (1988 $) 5-21
5-7 Summary of Retrofit Control Costs and Cost Effectiveness
for Model OTVC's using 1,1,1-trichloroethane (1988 $).... 5-22
5-8 Summary of Retofit Control Costs and Cost Effectiveness
for Model OTVC's using Trichlorotrifluoroethane (1988 $). . . 5-23
5-9 Model Cleaner Parameters for In-Line Cleaners 5-26
5-10 Summary of Retrofit Control Costs and Cost Effectiveness
for Model In-Line Cleaners using Methylene Chloride (1988 $). 5-30
5-11 Summary of Retrofit Control Costs and Cost Effectiveness
for Model In-Line Cleaners using Perchloroethylene (1988 $) . 5-31
5-12 Summary of Retofit Control Costs and Cost Effectiveness
for Model In-Line Cleaners using Trichloroethylene (1988 $) . 5-32
5-13 Summary of Retrofit Control Costs and Cost Effectiveness
for Model In-Line Cleaners using 1,1,1-Trichloroethane
(1988 $) 5-33
5-14 Summary of Retrofit Control Costs and Cost Effectiveness
for Model In-Line Cleaners using Trichlorotrifluoroethane
(1988 $) 5-34
VI
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LIST OF FIGURES
Number Page
3-1 Open-top vapor cleaner 3-4
3-2 Water Separator with Cooling Coil 3-6
3-3 Two compartment vapor cleaner 3-9
3-4 Two compartment vapor cleaner with offset boiling chamber . . 3-10
3-5 Open-top vapor cleaner with lip exhaust 3-12
3-6 Cross-rod conveyorized cleaner 3-15
3-7 Monorail conveyorized cleaner 3-16
3-8 Mesh belt conveyorized cleaner 3-17
3-9 Schematic diagram of a conveyorized photoresist stripping
machine 3-19
3-10 Vibra cleaner 3-21
3-11 Ferris wheel cleaner 3-22
3-12 Carburetor cleaner 3-24
3-13 OTVC idling emission sources 3-27
3-14 In-line cleaner emission sources 3-31
3-15 OTVC workload related emission sources 3-33
4-1 Typical OTVC covers 4-8
4-2 Open top vapor cleaner with freeboard refrigeration device. . 4-11
4-3 Freeboard chiller tests - idling conditions 4-13
4-4 Freeboard chiller tests - working conditions 4-14
4-5 Effect of primary condenser temperature on uncontrolled idle
and working conditions 4-17
4-6 Open Top Vapor Cleaner with Increased Freeboard 4-21
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LIST OF FIGURES
Number paqe
4-7 Solvent Loss Rate Versus Freeboard Height for Gensolv/ D
Under Idle Conditions 4-23
4-8 Effect of Freeboard Ratio - Working Conditions: 6 OTVC
Tests 4-24
4-9 Effect of Wind Speed 4-27
4-10 Lip Exhaust Effects - Idling Conditions 4-29
4-11 Lip Exhaust Effects - Working Conditions 4-30
4-12 Enclosed Open Top Vapor Cleaners 4-31
4-13 Automated Parts Handling System 4-37
4-14 Baffled Monorail In-line Cleaner 4-55
4-15 Baffled Monorail In-line Cleaner with Superheat Device. . . . 4-54
vm
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1.0 INTRODUCTION
This document applies to cleaning machines that use halogenated
solvents. It does not pertain to machines, primarily maintenance cleaners,
that use petroleum distillate type solvents (such as mineral spirits and
Stoddard solvents).
The use of halogenated solvents to clean or otherwise condition the
surface of metal parts, electronic components, and other nonporous substrates
is well established. The five commonly used halogenated solvents (methylene
chloride, trichloroethylene, perchloroethylene, trichlorotrifluoroethane, and
1,1,1-trichloroethane) possess the physical characteristics necessary to
handle a variety of industrial cleaning situations. They can dissolve many
common residues from manufacturing processes, have little or no flammability,
and can achieve a high degree of cleanliness, even on very small or intricate
parts. The popularity of halogenated solvent cleaning is evidenced by the
fact that hundreds of millions of pounds of the five solvents are consumed in
cleaning machines each year.
However, the Environmental Protection Agency is concerned about the
widespread use of the five solvents for several reasons. First, trichloro-
trifluoroethane (CFC-113) and 1,1,1-trichloroethane (TCA) have been
implicated in depletion of the protective stratospheric ozone layer. Second,
methylene chloride, perchloroethylene, and trichloroethylene have shown
evidence of being carcinogens in animals, and likely will be classified by
the Agency as possible or probable human carcinogens. Finally,
trichloroethylene and some components of solvent blends are photochemically
reactive and contribute to the problem of unacceptably high ground level
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ozone concentrations in many urban areas across the United States. For
solvent cleaning operations, these concerns are significant because the vast
majority of solvent cleaner consumption stems from fugitive loss of solvent
into the workplace, and from there, into the atmosphere. Smaller, but still
significant, amounts of the halogenated solvent consumption ends up in still
bottoms or cleanout residues that must be disposed of as hazardous waste.
Usually, relatively minor amounts enter industrial wastewaters from
halogenated solvent cleaning operations.
The Agency has announced its intent to list methylene chloride,
perchloroethylene, and trichloroethylene as hazardous air pollutants and
anticipates regulating them under the Clean Air Act. The Agency also has
promulgated regulations implementing the Montreal Protocol on Substances that
Deplete the Ozone Layer (53 FR 30566, August 12, 1988). At present, the only
affected chemical widely used in halogenated solvent cleaners is CFC-113.
The regulations call for CFC-113 production cuts to 50 percent of 1986
production levels by the year 1998. However, data recently analyzed by
atmospheric scientists suggest that the ozone layer is being depleted more
rapidly than predictive models indicated. Therefore, the Agency anticipates
revisions to the Montreal Protocol to further reduce environmental release of
chemicals capable of delivering chlorine or bromine to the stratosphere and
catalyzing ozone destruction. Possible revisions include total phaseout of
the CFC's currently subject to the Montreal Protocol, plus addition of TCA,
and possibly other chemicals, to the list of covered chemicals and
restrictions on TCA production. Beyond this, the Administration of EPA has
announced a commitment on the part of the United States to totally phase out
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by the year 2000 chemicals covered by the current Montreal Protocol.
Regarding photochemically reactive cleaning solvents (VOC), the Clean
Air Act (CAA) identified December 31, 1987, as the latest date for attainment
of the nation ambient air quality standard (NAAQS) for ozone. As of this
writing, many areas of the country are not in attainment with the ozone
NAAQS. The Agency has proposed to require States that have ozone
nonattainment areas to submit revised State implementation plant (SIP's) that
describe what steps will be taken to attain the standard (52 FR 45044,
November 24, 1987). This likely means that States will have to place
additional controls on sources of VOC, including cleaning solvents.
Another recent action is the Occupational Safety and Health
Administration's (OSHA) promulgation of revised permissible exposure limits
(PEL) for hundreds of chemicals, including trichloroethylene and
perchloroethylene (54 FR 2329, January 19, 1989). The OSHA also is working
on a separate action to revise the PEL for methylene chloride. The PEL'S for
trichloroethylene and perchloroethylene were revised downward significantly.
Considering the promulgated and pending actions affecting the five
solvents and their widespread use in cleaning operations, the Agency saw a
need to disseminate emission control information on solvent cleaners. This
document is intended primarily to inform State and local air pollution
control agencies and solvent cleaner operators of available techniques to
reduce solvent emissions and of available alternative cleaning technologies
that can often be used to completely eliminate halogenated solvent use.
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2.0 SUMMARY
Halogenated solvent cleaners commonly employ one of five halogenated
solvents; 1,1,1-trichloroethane (TCA), trichloroethylene (TCE),
perchloroethylene (PCE), methylene chloride (MC), and trichlorotrifluoroethane
(CFC-113). Sometimes blends of these solvents or blends of halogenated
solvents with small amounts of nonhalogenated solvents are used. Historically,
hundreds of millions of pounds of the five solvents have been consumed annually
in solvent cleaners. Most of the consumed solvent ends up in the atmosphere.
Cleaning machines vary in size from small benchtop models to industrial
cleaners large enough to contain an automobile and in sophistication from
simple tanks containing solvent to highly automated multi-stage cleaners.
Machines are categorized into three types: cold cleaners, open top vapor
cleaners (OTVC's), and in-line or conveyorized cleaners. Cold cleaners make
use of room temperature liquid solvent for removing soils. Although many cold
cleaners do not use halogenated solvent, some that do are maintenance machines
often called "carburetor cleaners." They use a solvent mixture containing MC.
Open top vapor cleaners heat the solvent to boiling and create a solvent vapor
zone within the machine. Parts to be cleaned are lowered into the cleaner's
vapor zone. Solvent vapor condenses on cooler parts dissolving and flushing
away soils. In-line cleaners are enclosed devices distinguished by a conveyor
system to continuously supply a stream of parts for cleaning. Cold cleaners
and OTVC are batch operated. In-line cleaners can be vapor cleaners or cold
cleaners; most are vapor cleaners. Data on the number of cleaners in use are
scarce. Using available industry information, it is estimated that there are
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around 100,000 carburetor cleaners using MC, 25,000 - 35,000 OTVC, and several
thousand in-line cleaners.
Emissions from solvent cleaners originate from sources such as: diffusion
or evaporation of solvent from the air/solvent vapor interface, evaporation of
solvent from cleaned parts as they are withdrawn from the cleaner, equipment
leaks, and solvent storage and transfer losses. The majority of solvent
consumed in a cleaner is lost to the air, some is lost to disposal of cleanout
waste and distillation residue, and minor amounts may end up in facility
wastewater. Generally, the carburetor cleaners are small emission sources.
Most employ a solvent blend that forms a water layer above the liquid solvent,
thereby dramatically reducing evaporative loss. In-line cleaners and OTVC's are
more significant sources. Regularly used OTVC's can emit a few tons or less of
solvent per year or up to perhaps 30 or 40 tons, depending heavily on the size
of the machine, the type of parts cleaned, hours of operation, design of the
cleaner, control equipment employed, and the operating practices followed.
In-line cleaners typically emit more solvent than OTVC's, primarily because of
the high volume of parts cleaned. It is common for an in-line cleaner to emit
more than 20 tons of solvent per year; some have been reported to emit over
100 tons per year.
To reduce solvent cleaner emissions, and thereby solvent consumption, it
is necessary first to purchase a cleaner (or retrofit an existing cleaner) with
solvent saving devices/features and second to operate and maintain the cleaner
properly. Tables 2-1 through 2-3 list the hardware and operating practices
that have been shown to reduce solvent consumption in OTVC's, in-line cleaners,
and cold cleaners, respectively. Some control devices primarily reduce
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TABLE 2-1. AVAILABLE CONTROL TECHNIQUES FOR OTVC OPERATIONS
Source of
Solvent Loss
Available Control Hardware
Operating Practices
Air/Solvent
Vapor
Interface
Workload
rv>
Fugitive
t
•
•
1.0 FBR (or higher)
Freeboard refrigeration device
Reduced primary condenser temperature
Automated cover
Enclosed design
Carbon adsorber
Reduced air/solvent vapor interface area
Automated parts handling at 11 fpm or less
Carbon adsorber
Hot vapor recycle/superheated vapor
system
Sump cooling system for downtime
Downtime cover
Closed piping for solvent and waste
solvent transfers
Leakproof connections; proper materials
of construction for machine parts and gaskets
t Place machine where there are no drafts
• Close cover during idle periods
t Rack parts so that solvent drains
properly
• Conduct spraying at a downward angle
and within the vapor zone
• Keep workload in vapor zone until
condensation ceases
• Allow parts to dry within machine
freeboard area before removal
t Routine leak inspection and
maintenance
• Close cover during downtime
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TABLE 2-2. AVAILABLE CONTROL TECHNIQUES FOR IN-LINE OPERATIONS
Solvent Loss
Mechanism
Machine Design
Operating Practices
Air/Solvent
Vapor
Interface*5
Workload
Fugitive
1.0 freeboard ratio
Freeboard refrigeration device3
Reduced primary condenser temperature3
Carbon adsorber
Minimized openings (clearance between parts
and edge of machine opening is less than
10 cm or 10% of the width of the opening)
• Conveyor speed at 11 fpm or less
t Carbon adsorber
• Hot vapor recycle/superheated vapor
system
t Sump cooling system for downtime
t Downtime cover or flaps
0 Closed piping for solvent and waste
solvent transfers
t Leakproof connections; proper materials
of construction for machine parts and
gaskets
t Rack parts so that solvent drains
properly
t Conduct spraying at a downward angle
and within the vapor zonea
• Keep workload in vapor zone until
condensation ceases
• Allow parts to dry within machine
before removal
• Routine leak inspection and
maintenance
t Cover ports during downtime
Applies to in-line vapor cleaners, but not in-line cold cleaners.
}Air/solvent interface for in-line cold cleaners.
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TABLE 2-3. AVAILABLE CONTROL TECHNIQUES FOR COLD CLEANERS
Machine Design
Operating Practices
§ Manual cover
• Water cover with internal baffles
• Drainage facility (internal)
• Close machine during idling and downtime
• Drain cleaned parts for at least
15 seconds before removal
• Conduct spraying only within the confines of
the cleaner
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air/solvent interface losses while others primarily reduce workload related
losses. Carbon adsorbers will control both. All control hardware would not be
used on one machine as redundant emission control would result. However,
selected combinations of the available control hardware will produce low
emission machines. Chapter 4 contains more information on control device
combinations. All listed operating practices can be usefully employed on any
solvent cleaner.
Many States already regulate solvent cleaners, either for VOC control or
for toxic pollutant control. However, the machines controlled to present State
standards may be further improved by adoption of some additional control
measures described in this document. A significant fraction of existing
machines likely are uncontrolled. On the other hand, several equipment
manufacturers currently are selling well designed solvent cleaners using the
listed controls and some have improved designs on the drawing board or in
prototype stage.
On existing machines, the amount of control achieved by implementing new
control measures depends on the measures chosen and the degree of control
already provided on the cleaner. Relative to an uncontrolled case, installing
a combination of hardware controls and implementing good operating practices
can reduce emissions in excess of 70 percent. Chapter 4 describes in more
detail control efficiency estimates for various scenarios. For new machines,
it is difficult to pinpoint what an emission rate reflecting good control
should be; it depends most heavily on the cleaner size, type of workload, and
working schedule. However, in the idling mode (no parts throughput), data
obtained by the Agency indicate that OTVC's with controls are able to achieve
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an emission rate of 0.07 lb/hr/ft2 of air/solvent interface area or lower.
Data on working mode emission rates for OTVC's and in-line cleaners show wide
variation.
Costs for purchasing, installing, and operating control devices listed in
the tables vary widely according to the type of controls selected and the
degree of sophistication. For instance, the cost of a simple mechanical hoist
operated by pushbuttons may be less than $1,000, whereas a completely
automated, programmable robot elevator may cost $10,000 or more. Both devices,
properly operated, will reduce workload emissions over a manually operated
cleaner. The more expensive model, however, offers convenience, flexibility,
and reduced labor requirements that are not possible with the less expensive
model. Costs detailed in Chapter 5 represent basic equipment needed to
accomplish the emission reduction objective, not equipment providing additional
features unrelated to emission reduction. Overall, the cost analysis shows
many instances where control can be applied cost effectively. Some control
scenarios show net annualized cost savings when controls are applied to an
uncontrolled machine.
Although this document focuses on controls for cleaners using one of the
five common halogenated solvents or solvent blends containing them, it is
possible in many instances to eliminate their use entirely. In some cases
water based cleaners can replace existing solvent systems. Additionally, new
solvents and blends are being introduced that do not contain any of the five
halogenated solvents. Most of these new solvents are being developed to
replace use of CFC-113, which is being phased out. Some of them are based on
heavy hydrocarbons, and some contain different partially halogenated compounds.
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Although these alternative cleaning agents exist or will be available in
the future, they may bring with them a different set of disadvantages. For
example, they have not yet proven to be replacements (for technical reasons) in
all situations currently handled by one of the five solvents, toxicity tests
have not been completed on some of the proposed substitutes, water based
cleaners may be relatively high energy users and may generate large wastewater
streams, and moving to a substitute cleaning agent generally means buying a new
cleaning machine or making expensive modifications to existing equipment.
These considerations must be taken into account in decisions on how best to
reduce emission of the five halogenated solvents.
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3.0 ORGANIC SOLVENT CLEANER CHARACTERISTICS AND EMISSIONS
3.1 GENERAL
Organic solvent cleaners use organic solvents, solvent blends, or their
vapors to remove water-Insoluble soils such as grease, oils, waxes, carbon
deposits, fluxes and tars from metal, plastic, fiberglass, printed circuit
boards, and other surfaces. Organic solvent cleaning is performed prior to
processes such as painting, plating, inspection, repair, assembly, heat
treatment, and machining. The same type of machine that is used in cleaning
applications can also be used for drying wet parts (by displacing surface
moisture with solvent and evaporating the solvent) and for conditioning the
surface of plastic parts. Both nonhalogenated and halogenated solvents may
be used in solvent cleaning. Examples of the nonhalogenated solvents
typically used are mineral spirits, Stoddard solvents, and alcohols. The
five commonly used halogenated solvents used are methylene chloride (MC),
perchloroethylene (PCE), trichloroethylene (TCE), 1,1,1-trichloroethane
(TCA), and trichlorotrifluoroethane (CFC-113). These five solvents can be
used alone or in blends which contain two or more halogenated solvents and
sometimes alcohols.
Organic solvent cleaning does not constitute a distinct industrial
category but rather is an integral part of many major industries. The five
2-digit Standard Industrial Classification (SIC) codes that use the largest
quantities of halogenated solvents for cleaning are: SIC 25 (furniture and
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fixtures), SIC 34 (fabricated metal products), SIC 36 (electric and
electronic equipment), SIC 37 (transportation equipment) and SIC 39
(miscellaneous manufacturing industries). Additional industries that use
halogenated solvents in cleaning include SIC 20 (food and kindred products),
SIC 33 (primary metals), SIC 35 (nonelectric machinery), and SIC 38
(instruments and clocks). Nonmanufacturing industries such as railroad,
bus, aircraft, and truck maintenance facilities; automotive and electric
tool repair shops; automobile dealers; and service stations (SIC 40, 41, 42,
45, 49, 55, and 75, respectively) also use organic solvent cleaners.
This chapter describes typical organic solvent cleaning processes and
emissions from machines using halogenated solvents. Section 3.2 describes
the various types of cleaners. Section 3.3 identifies emission mechanisms
and presents test data on cleaner emission rates. Section 3.4 discusses
typical emission scenarios for vapor cleaners.
3.2 ORGANIC SOLVENT CLEANING PROCESSES
There are three basic types of solvent cleaning equipment: open top
vapor cleaners (OTVC's), in-line (cold and vapor) cleaners, and batch cold
cleaners. The vast majority of halogenated solvent use is in vapor
cleaning, both open top and in-line. The primary solvents used in batch
cold cleaners are mineral spirits, Stoddard solvents, and alcohols. Very
little halogenated solvent use has been identified in batch cold cleaning.
In 1987, an estimated 150,000 metric tons (Mg) of halogenated solvents
were used by OTVC's; 50,000 Mg by in-line vapor cleaners; 30,000 Mg by
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in-line cold cleaners; and 2,000 Mg by cold cleaners. Furthermore, an
estimated 25,000 to 35,000 OTVC's; 2,000 to 3,000 in-line vapor cleaners;
500 to 1,000 in-line cold cleaners; and 100,000 cold cleaners were using
halogenated solvents in 1987.
A description of OTVC's is presented in Section 3.2.1. Section 3.2.2
presents information on in-line cleaners while Section 3.3.3 describes cold
cleaners.
3.2.1 Open TOD Vapor Cleaners
Open top vapor cleaners are used primarily in metalworking operations
and other manufacturing facilities. They are seldom used for ordinary
maintenance cleaning because cold cleaners using petroleum distillate
solvents can usually perform this type of cleaning at a lower cost.
Exceptions include maintenance cleaning of electronic components, small
equipment parts, and aircraft parts, where a high degree of cleanliness is
needed.
A basic OTVC, shown in Figure 3-1, is a tank designed to generate and
contain solvent vapor. At least one section of the tank is equipped with a
heating system that uses steam, electricity, hot water, or heat pumps to
boil liquid solvent. As the solvent boils, dense solvent vapors rise and
displace the air inside the tank. The solvent vapors rise to the level of
the primary condensing coils. Coolant (such as water) is circulated or
recirculated through the condensing coils to provide continuous condensation
of rising solvent vapors and, thereby, create a controlled vapor zone which
prevents vapors from escaping the tank. Condensing coils generally are
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Condensing Coils
Temperature
Indicator
Cleanout Door
Solvent Level Sight Glass
Freeboard
Condensate Trough
Water
Separator
Heating Elements
Work Rest and Protective Grate
Figure 3-1. Open Top Vapor Cleaner
(N
CO
(£>
3-4
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located around the periphery of the inside walls of the cleaner, although in
some equipment they consist of offset coils on one end or side of the
cleaner.
All machines have covers of varying design to limit solvent losses and
contamination during downtime or idle time. Additional control of the
solvent vapor is provided by the freeboard, which is that part of the tank
wall extending from the top of the solvent vapor level to the tank lip. The
freeboard ratio (FBR), or ratio of freeboard height to machine width
(smaller dimension of vapor-air interface area), usually ranges from 0.75 to
1.0, depending on the manufacturer's design. The freeboard ratio can be as
low as 0.5 on some older machines. Air currents within an OTVC can cause
excessive solvent emissions. Increasing the freeboard ratio reduces the
disturbance of the vapor zone due to workplace air currents and slows
solvent diffusion out of the machine.
Moisture may enter the OTVC on workloads and also and can condense from
ambient air on primary cooling coils or freeboard refrigeration coils along
with solvent vapors. If allowed to accumulate, water in an OTVC will lead
to higher emissions and may contribute to solvent decomposition and
corrosion in the cleaner. Therefore, nearly all vapor cleaners are equipped
with a water separator based on the principle depicted in Figure 3-2. The
condensed mixture of water and solvent is collected in a trough below the
condenser coils and directed to the water separator. The water separator is
a simple container in which the water phase (being essentially immiscible
with and less dense than halogenated solvents) separates from liquid
solvent. The water is directed to disposal while solvent is allowed to
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Cooling System
Coolant Inlet
Water Overflow
Solvent Outlet
Coolant Outlet
Solvent Inlet
Drain
Figure 3-2. Water Separator with Cooling Coil
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return to the cleaner. Cooling coils may be used inside the separator to
cool condensed solvent and enhance solvent/water separation.
To further reduce water contamination or to replace the water
separator, some manufacturers produce machines using a canister of
desiccant, such as a molecular sieve. Use of dessicants prevents prolonged
contact between water and solvent, which can result in removal of water-
soluble stabilizers or co-solvents (such as alcohols) from certain solvents
and blends. Dessicants also prevent corrosion due to hydrolysis of the
solvent.
During the vapor cleaning operation, solvent vapors condense on the
cooler workload entering the vapor zone. Condensing solvent dissolves some
contaminants and flushes both dissolved and undissolved soils from the
workload. Condensed solvent and dissolved or entrained contaminants then
drain back into the sump below. When the temperature of the workload
reaches that of the vapor, condensation ceases and the vapor phase cleaning
process is complete.
Organic impurities (greases, soils, etc.) cleaned from parts will
accumulate in the solvent sump. However, they do not appreciably
contaminate the solvent vapors because of their higher boiling points.
Since the solvent vapor remains relatively pure, solvent can be used for
longer periods with vapor cleaning than with cold cleaning where the solvent
more quickly becomes contaminated with dissolved and suspended impurities.
Eventually, accumulated impurities will compromise the performance or safety
of vapor cleaners. To avoid these problems, contaminated solvent is
periodically drained from the machine and replaced with fresh solvent.
3-7
-------
Alternatively, a still adjacent to the cleaner can be used to extract
soils building up in the solvent sump and return clean solvent to the
machine. The solvent feed system to the still can include a filter to
remove insolubles such as metal fines. Using a still can increase the
useful life of solvent and will concentrate the impurities. The lower
volume, concentrated waste stream from the still will be less expensive to
properly dispose of. Waste streams from solvent cleaning operations are
considered hazardous wastes under the EPA's regulations implementing the
Resource Conservation and Recovery Act (RCRA).
Variations in design of vapor cleaners reflect their many industrial
applications. Workload characteristics and the degree of cleanliness
required by the particular application dictate many additional features on
the basic model. Additional examples of vapor cleaners are shown in
Figures 3-3 and 3-4. These figures show OTVC's with two chambers: one for
generating the solvent vapor, the other for immersion cleaning or for
spraying applications.
One OTVC design variation is an immersion-vaporspray cycle. In this
design, the workload is lowered into a warm or boiling immersion compartment
for precleaning. The immersion compartment may be equipped with
ultrasonics. In a machine using ultrasonics, high frequency sound waves are
used to produce pressure waves in the liquid solvent. In areas of low
pressure within the liquid, minute vapor pockets are formed. These pockets
collapse as the pressure in the zone cycles to high pressure. The constant
creation and collapse of these vapor pockets (called cavitation) provides a
scrubbing action to aid cleaning. Ultrasonically agitated liquids often
3-8
-------
Condensing
Coils
Solvent
Vapor Zone
Warm Solvent
Overflow Dam
Solvent
Boiling Chamber
Freeboard
Water
Separator
Warm Solvent or Ultrasonics
Immersion Chamber
Figure 3-3. Two Compartment Vapor Cleaner
o
f^
o
3-9
-------
Condensing
Coils
Offset Solvent
Boiling Chamber
Freeboard
Solvent Warm Solvent or Ultrasonics
Overflow Dam Immersion Chamber
Figure 3-4. Two Compartment Vapor Cleaner with Offset
Boiling Chamber
CM
o
3-10
-------
need to be heated to specific temperatures to achieve optimum cavitation.
After this first stage of cleaning is completed, the workload is cleaned in
a vapor section and then sprayed with solvent. Many other cleaning cycles
are possible, some of which incorporate non-boiling solvent sections with
vapor sections. Spraying may not be necessary or desirable for some
applications.
Another common variation in design is a vapor-spray-vapor cycle. In
this design, the workload is lowered into the vapor zone where the
condensing solvent performs the preliminary cleaning. After condensation
ceases, the workload is sprayed with warm solvent. The pressure of the
spray aids in physical removal of soil. In some cases, the warm spray may
be cooler than the workload and will lower the workload temperature
promoting further solvent condensation on the workload. The spray nozzle
must be below the vapor line to avoid spraying solvent directly to the
atmosphere and directed downward to avoid turbulence at the air/solvent
vapor interface.
Lip or slot exhausts, such as shown in Figure 3-5, are designed to
capture solvent vapors escaping from the OTVC and carry them away from the
operating personnel. These exhaust systems disturb the vapor zone or
enhance diffusion, thereby increasing solvent losses. The increased losses
can be significant. In properly designed lip exhaust systems, the cover
closes below the lip exhaust inlet level. The effect of lip exhausts is
discussed further in Chapter 4.
Parts cleaning in an OTVC can be performed either manually or with the
use of an automated parts handling system. In manual operation, the
3-11
-------
Exhaust Outlet
(to control device
or to atmosphere)
Lip Exhaust
Inlet
Figure 3-5. Open Top Vapor Cleaner with Lip Exhaust
oc
in
O5
in
cs
O)
to
3-12
-------
attendant must lower the parts basket into the cleaner and remove the basket
once the cleaning has been completed. An electrically operated parts
handling system can be operated by push buttons or some can be programmed to
cycle parts through the cleaning cycle automatically. With a hoist, the
speed of part entry and removal can be controlled and will be consistent
from cycle to cycle.
3.2.2 In-line Cleaners
In-line cleaners (also called conveyorized cleaners) employ automated
load on a continuous basis. Although in-line cleaners can operate in the
vapor or non-vapor phase, the majority of all in-line machines using
halogenated solvents are vapor cleaners. A continuous or multiple-batch
loading system greatly reduces manual parts handling associated with open
top vapor cleaning or cold cleaning. The same cleaning techniques are used
in in-line cleaning but usually on a larger scale than with open top units.
In-line cleaners are nearly always enclosed, except for parts/
conveyor inlet and exit openings, to help control solvent losses from the
system. In-line cleaners are used by a broad spectrum of industries but are
most often found in plants where there is a constant stream of parts to be
cleaned, where the advantages of continuous cleaning outweigh the lower
capital cost of the batch loaded OTVC. Usually, an in-line cleaner is
individually designed for a specific workload and production rate situation,
rather than being an "off the shelf" item.
There are five main types of in-line cleaners using the halogenated
solvents: cross-rod, monorail, belt, strip, and printed circuit board
3-13
-------
processing equipment (photoresist strippers, flux cleaners, and developers).
While most of these may be used with cold or vaporized solvent, the last two
are almost always vapor cleaners. The photoresist strippers are typically
cold cleaners.
The cross-rod cleaner (Figure 3-6) obtains its name from the rods from
which parts baskets are suspended as they are conveyed through the machine
by a pair of power-driven chains. The parts are contained in pendant
baskets or, where tumbling of the parts is desired, perforated or wire mesh
cylinders. These cylinders may be rotated within the liquid solvent and/or
the vapor zone. This type of equipment lends itself particularly well to
handling small parts that need to be immersed in solvent for satisfactory
cleaning or which require tumbling to drain solvent from cavities and/or to
remove metal chips.
A monorail vapor cleaner (Figure 3-7) is usually chosen when the parts
to be cleaned are being transported between manufacturing operations on a
monorail conveyor. The monorail cleaner is well suited to automatic
cleaning with solvent spray and vapor. It can be of the straight-through
design illustrated or can incorporate a u-turn within the machine so that
parts exit through an opening parallel to the entrance opening. The u-turn
monorail cleaner benefits from lower vapor loss because the design
eliminates the possibility of drafts flowing through the machine.
Both the belt cleaner (Figure 3-8) and the strip cleaner are designed
to allow simple and rapid loading and unloading of parts. A belt cleaner
conveys parts through a long and narrow boiling chamber in which the parts
are cleaned either by the condensing vapor or by immersion in the solvent
sump. The strip cleaner is similar to the belt cleaner except that the
3-14
-------
Conveyor
Path
Chain
Supports
Work /
Basket'
Water
Jacket
Boiling Chamber
Figure 3-6. Cross-rod In-line Cleaner
co
CM
§
3-15
-------
Conveyor
Path
Conveyor
Path
Spray
Pump
Boiling
Chamber
Water
Jacket
Figure 3-7. Monorail In-line Cleaner
CN
00
to
3-16
-------
Conveyor
Path
Mesh
Belt
Boiling
Chamber
Figure 3-8. Mesh Belt In-line Cleaner
ic
r-
oo
(O
-------
strip itself is the material being cleaned. As with the belt cleaner, the
material in a strip cleaner can be cleaned by the condensing vapor or by
immersion in the solvent sump.
Cleaning of printed circuit boards is a common application of a type of
mesh belt cleaner (Figure 3-9). In the production of printed circuit
boards, solvent-based photo-processable resists can be used. The circuit
pattern is contained in an artwork film. This pattern is reproduced by
projecting ultraviolet rays through the artwork film onto a copper sheet
covered with resist. A developer (typically TCA) dissolves the unexposed
areas of the resist, and thereby, reveals the circuit pattern. The
resist-covered board is then placed in plating solutions to add more metal
to the circuit pattern areas. Next, a photoresist stripper dissolves the
remaining resist. The circuit boards are then put in an alkaline etching
solution to remove all the copper in the noncircuitry areas. The processing
is completed by passing the circuit boards through a wave of molten solder.
Due to the nature of the materials being cleaned, photoresist strippers
use ambient (room temperature) solvents. Spraying and brushing may be used
to enhance cleaning. Methylene chloride is the solvent most often used in
photoresist stripping; however, the printed circuit board industry has
largely converted to aqueous and semi-aqueous materials to replace the use
of both TCA and MC. The switch to aqueous systems is discussed further in
Chapter 4.
Circuit board cleaners are used to dissolve and remove flux from the
circuit board after the molten soldering step. Unlike photoresist
strippers, circuit board cleaners have a heated or boiling sump. However,
circuit board cleaning occurs in the liquid solvent (not vapor) phase,
3-18
-------
Exhaust
Work Flow
PC
Board
, 0 0*1 0
n Spray
Nozzles
'
X° 8I8
/ ;
O
o
Pump — ^
r^Ll
^••H
1
/ /
/ /
/ 1 1 1 1 1
o o o g o p
o o o 6 o o
J 1 1 1 1
/?\
—
— - - - — - -
o
rn
A A A
o o
^TTT
T
0 0
A o
Exhau
W,
Pump
vn
ff— •
Tf\ •»
••
ster Rinse
0 0
3 0
1 « 1
.
/
st Damper
Conveyor
Rollers
g o o o o /
o o
o o or
1
Drying
Area
Solvent
Clean Solvent
(from Distillation
System)
To Wastewater
Treatment System
Figure 3-9. Schematic Diagram of an In-line Photoresist Stripping
Machine
-------
although a vapor phase may be present. Circuit board cleaners commonly use
chlorofluorocarbons; however, aqueous fluxes and aqueous flux cleaners are
becoming more widely used in the printed circuit industry as a replacement.
Again, this switch is discussed further in Chapter 4.
3.2.3 Hybrid Cleaners
As the solvent cleaning industry has developed, specialized cleaning
devices that do not fit into the OTVC or in-line cleaner categories have
emerged. Among these cleaners are the vibra, the ferris wheel, and the
carousel cleaners.
In the vibra cleaner (Figure 3-10), soiled parts are fed through a
chute into a pan flooded with boiling solvent at the bottom of the cleaner.
The pan is connected to a vibrating spiral elevator. Both the pan and
spiral elevator vibrate, causing the parts to move from the pan up the
spiral to the exit chute. The cooler parts condense solvent vapor as they
are vibrated up the spiral and dry as soon as they leave the vapor zone.
These cleaners are capable of processing large quantities of small parts.
Since the vibrating action creates considerable noise, the equipment must be
acoustically insulated or enclosed in a noise-control booth.
The ferris wheel cleaner (Figure 3-11) is one of the least expensive
and smallest hybrid cleaners. It is a vapor cleaner and commonly features
perforated parts baskets, as does the cross-rod cleaner. As a large gear
wheel rotates, it tumbles the perforated baskets attached to it via smaller
gears, allowing better contact of the parts with the solvent, and draining
cavities that could otherwise retain solvent.
3-20
-------
Workload Discharger Chute
Ascending
Vibrating
Trough
Distillate Return
for Counter-
flow Wash
Figure 3-10. Vibra Cleaner
cr
in
O)
<•>
cs
§
3-21
-------
Work
Basket
Gear to Tumble
Baskets
Boiling
Chamber
Figure 3-11. Ferris Wheel Cleaner
(N
oo
-------
The carousel cleaner is a four-chamber machine which is similar to the
ferris wheel cleaner except that parts travel on a horizontal plane. The
first chamber is the loading area. The remaining three chambers are
cleaning units. All cleaning chambers can contain halogenated solvent
(typically vapor phase with or without immersion sumps), or one chamber can
be used for steam cleaning. Usually, this type of machine is used to clean
large parts such as airplane wheels. In operation, a four-arm carousel
carries the parts to be cleaned sequentially through each of the four
chambers.
3.2.4 Cold Cleaners
Cold cleaners use room temperature liquid solvent for parts cleaning.
Most cold cleaners are small maintenance cleaners or parts washers using
either aliphatic petroleum distillates such as mineral spirits or sometimes
alcohol blends or naphthas. These are not covered in this document.
Cold cleaning operations include spraying, flushing, solvent or parts
agitation, wipe cleaning, and immersion. The only machines using
halogenated solvent in a cold cleaning application (except for non-vapor
in-line cleaning) are of a type called carburetor cleaners. In these
cleaners, methylene chloride is blended with other solvents and additives to
reduce flammability and increase dissolving power. A typical carburetor
cleaner is shown in Figure 3-12. Emissions from these cleaners are
typically well controlled because the cleaning solution used contains water
which forms as a water layer above the solvent mixture in the tank. The
water layer
3-23
-------
Air Motor and
Drive Assembly
Basket
"On" and "Off'
Valve
Figure 3-12. Carburetor Cleaner
tr
O)
n
3-24
-------
drastically reduces evaporation of methylene chloride. Although some cold
cleaners have been sold in the past for use with halogenated solvents, no
manufacturer could be located that is currently marketing machines for use
with these solvents, other than those using the carburetor cleaning
solutions.
3.3 EMISSION MECHANISMS AND TYPES
There are many sources of solvent loss to the atmosphere from an
organic solvent cleaner. Two significant sources are air/solvent vapor
interface losses and workload related losses. Air/solvent vapor interface
losses during idling consist of solvent vapor diffusion (or evaporation from
liquid solvent in a cold cleaner) and solvent vapor convection induced by
warm freeboards. Workload related losses (hereafter called workload losses)
are solvent emissions that are created or increased by the introduction and
extraction of parts during the cleaning process and by spraying of parts
during cleaning (if sprays are used). Other potentially significant losses
that contribute to the total solvent emissions from a solvent cleaner
include filling/draining losses, wastewater losses, start-up/shutdown
losses, downtime losses, and losses from leaks from the cleaner or
associated equipment. Diffusion and convection losses are described in
Section 3.3.1, while workload and "other" losses are described in Sections
3.3.2 and 3.3.3, respectively.
3-25
-------
3-3'! Air/Solvent Vapor Interface Losses during Idling (Idling Losses!
3'3-1-1 Open Top Vapor Cleans The principal emission sources in
idling OTVC are shown in Figure 3-13. These losses can be increased
dramatically by external factors.
The main source of idling losses from an OTVC is diffusion. Diffusion
is the movement of solvent vapors from the vapor zone to the ambient air
above. This occurs because molecules of solvent diffuse from the high
concentration in the vapor zone to the lower concentration in the air.
Diffusion rates are dependent on temperature since molecular activity
increases at higher temperatures. An idling machine will reach a point
where an equilibrium diffusion rate is established. At this point the
emission rate will not fluctuate greatly unless equilibrium conditions are
disturbed.
Additional losses can be caused by convection. The heat of the boiling
solvent is conducted from the boiling solvent and hot vapor to the walls of
the solvent cleaner. This heating of the walls creates a convective flow up
along the freeboard carrying solvent vapor out of the cleaner. The amount
of convective loss depends on how warm the freeboard walls become. If OTVC
walls are kept close to ambient conditions, convective losses will be
minimized. Some machines have a water jacket around the outside periphery
of the cleaner to help cool the walls of the machine and reduce the
convective losses. However, a water jacket is not necessary on all
machines. For example, if adequate cooling of the tank walls is provided by
primary coils in contact with the OTVC walls, a water jacket is not
necessary.
3-26
-------
Retractable
Cover
Water
Separator
Air Currents from
Building Ventilation
Freeboard
Area
I >
Solvent Vapor
Zone
Air/Solvent Interface
Boiling Solvent —
1. Diffusion of Solvent from Air/Solvent Vapor Interface
2. Convection of Solvent Vapor up Warm Tank Walls
3. Diffusion and Convection Losses Accelerated by Drafts
Across Tank Lip (or by Operation of Lip Exhaust Device)
_ Primary Condenser
Coils
cc
in
Figure 3-13. OTVC Idling Emission Sources
en
CD
-------
The diffusion rate equilibrium also can be disturbed if an air flow is
introduced across the air/solvent vapor interface as the result of room
drafts or a lip exhaust. Room drafts create turbulence in the interface
area. This can cause the air and solvent vapor to mix, creating a mixture
that is lighter than the pure solvent vapor and, therefore, is more readily
lost to the atmosphere. The room drafts also sweep solvent-laden air from
the freeboard area into the ambient air. This allows more solvent to
diffuse into the "fresh air" in the freeboard area.
Lip (or lateral) exhausts create similar disturbances across the
air/solvent vapor interface of the solvent cleaner. The exhaust system
draws in solvent-laden air from around the top perimeter of the solvent
cleaner to lower the solvent concentration in the area where operators are
working. As discussed in Chapter 4, these exhausts do not capture all of
the vapors that escape from the cleaner. Tests have shown that even
properly operated lip exhausts can double vapor cleaner diffusion losses.
Some lip exhaust systems include carbon adsorbers to collect the exhausted
solvent for reuse; however, emissions not captured by the lip exhaust remain
uncontrolled.
A summary of the available idling emission data for OTVC is presented
in Table 3-1. All of the data were obtained on uncovered machines with no
refrigerated freeboard devices or lip exhausts. The emission rates range
from 0.06 Ib/ft2/nour to 0.17 lb/ft*/hour. The variation in emission rates
for the same solvent can be explained by the varying primary condensing
temperatures during these tests. Emission rates are lowest in tests where
the primary condensing temperature of the cleaner is lowest. The use of a
reduced primary condenser temperature as a control technology is discussed
3-28
-------
TABLE 3-1. SUMMARY OF AVAILABLE TESTS - IDLING OTVC's
CO
ro
vo
rest *
-1
-2
-3
-«
-5
-6
-7
Solvent
Freon-TF
1,1,1-TCA
1,1,1-TCA
1.1,1-TCA
CFC-113
CFC-113
CFC-113
Cleaner.
Size (m )
0.3
0.9
0.9
0.9
0.9
0.9
0.9
FBR8
1.0
0.7
0.7
0.7
0.7
0.7
0.7
Cleaner
Make
Delta Sonics
Auto-Sonics
Auto-Sonics
Auto-Sonics
Auto-Sonics
Auto-Sonics
Auto-Sonics
Conditions
Primary
Condenser
Temperature
(oF)
55
50
70
85
40
50
70
Emission
Rate
(Ib/ftVhr)
0.060
0.087
0.120
O.U3
0.062
0.094
0.169
Reference
2
3
3
3
3
3
3
a
FBR = Freeboard ratio.
-------
in more detail in Chapter 4. At the mid-range primary condensing
temperature during the tests (Table 3-1; Tests 3 and 6), the emissions
ranged from 0.09 lb/ft*/hour to 0.12 Ib/ft2/hour.
3.3.1.2 In-line Cleaners. The primary sources of idling losses from
in-line vapor cleaners are the same as for OTVC's: convection and diffusion.
These types of losses are presented in Figure 3-14, and the mechanisms are
described in detail in the previous section. No data were available on
idling losses from in-line cleaners. However, the idling diffusional and
convective losses from these cleaners would likely be less per unit of
air/solvent vapor interface area than an OTVC since the units are almost
always enclosed and less subject to drafts.
3-3.1.3 Cold Cleaners. The source of solvent loss from an idle cold
cleaner is evaporation from the liquid surface and subsequent diffusion.
The rate of solvent loss is solvent dependent and is affected by room
drafts. As with OTVC's, room drafts can remove solvent laden air from above
the liquid surface, thus increasing equilibrium evaporation rates from
quiescent conditions. However, the only identified type of cold cleaner
using a halogenated solvent that is currently being manufactured is a'
carburetor cleaner, which contains some methylene chloride. As mentioned
previously, these units typically have water covers. Since the solvent is
heavier than and only slightly soluble in water, little solvent reaches the
air interface and evaporates.
3-30
-------
Exhaust
Exhaust
CO
I
to
Parts
Basket
Inlet
Port
Condenser ,
Coils
s^V -1
8 X
1 ^^^
1 Vapor ( \
I
_- '_L
Liquid
/^cx:
y~^^
3 ' ;
« i '
1. Diffusion of solvent from air/solvent vapor interface
2. Vapor up warm tank walls
3. Carry-out of liquid solvent on part and subsequent evaporation
4. Roof vent exhaust (where applicable)
Figure 3-14. In-line Cleaner Emission Sources
oc
s
-------
3.3.2 Workload Related Losses (Workload Losses!
Workload losses are defined as all losses that are caused or
Increased by the cycling of parts through the solvent cleaner. During the
operation of a solvent cleaner, the losses at the air/solvent vapor
interface continue. However, the rate of these losses will be increased due
to the disturbances caused by the parts cleaning.
3-3.2.1 Open TOD Vapor Cleaners. The losses that occur when an OTVC is
cleaning parts are depicted in Figure 3-15. The losses during workload
entry and cleaning and the losses during workload removal are shown in the
figure.
One of the causes of the increased losses during solvent cleaner
operation is the turbulence in the air/solvent vapor interface that occurs
when parts and parts baskets enter the cleaner. This loss includes the
increase in diffusional and convective losses that occur at the air/solvent
vapor interface. The amount of loss depends on the speed of the basket, as
well as the characteristics of the parts being cleaned. Part of this loss
can be the solvent vapor displaced out of the cleaner from a piston-type
effect as the parts are lowered into the cleaner. The amount of loss due to
parts entry is increased as the speed of parts introduction increases. The
piston effect is also greater when the parts and baskets take up a larger
percentage of the interface area. It is generally recommended that
workloads take up no more than 50 percent of the total interface area
although large workloads can be used if the lowering speed is very slow.
Also, if a large part is being lowered into a cleaner, the part can possibly
be angled to limit the amount of the piston effect.
3-32
-------
Workload
Entering
Water
Jacket
CO
CO
CO
Workload
Exiting
Water
Separator
1. Increased Diffusion and Mixing at Air/Solvent Vapor Interface due to
Piston Effect, Disturbance of Vapor Layer, and Spraying
2. Vapor Entrainment and Increased Diffusion and Mixing due to Turbulence
3. Carryout of Solvent on Cleaned Parts
Figure 3-15. OTVC Workload Related Emission Sources
es
o>
-------
Vapor line fluctuation also contributes to solvent loss. Several
factors can affect the amount of vapor line fluctuation. If very cold parts
or a large quantity of parts are introduced into the cleaner, more heat
will be required to bring the parts up to the temperature of the solvent
vapor. When the heat is transferred from the solvent vapor to the parts,
the vapor line lowers. As the vapor line rebuilds and rises back to its
original level, the air/solvent vapor mixture above the layer is displaced
out of the cleaner. One manufacturer has determined through testing that
solvent loss rates begin to increase substantially when the vapor line is
deflected by more than 2.5 inches. These test data also indicated that
solvent loss rates are about twice as high at a deflection of 10 inches as
they are at a deflection of 2.5 inches.4
During parts cleaning, additional losses can occur if sprays are used
to aid in cleaning. Spraying from either fixed nozzles or spray wands is
common. The sprayed solvent can cause turbulence in the air/solvent vapor
interface and vapor line lowering, thereby increasing emissions. If the
spray has too high a pressure, splashing of the solvent against the parts,
parts basket, or wall of the cleaner can also increase emissions. Both of
these spray sources should be mounted so that spraying occurs only beneath
the vapor zone.
As parts are removed from the cleaner, the air/solvent vapor interface
again is disturbed. As with workload entry, the speed of workload removal
directly affects the amount of solvent loss. The effect of parts movement
rate on emission rates is discussed in Chapter 4. A large portion of this
loss is vapor entrainment. If parts are extracted rapidly, solvent vapor
will be entrained behind the workload and pulled out of the cleaner (wake
effect).
3-34
-------
A final source of loss during workload removal is liquid dragout. This
includes liquid pooled in cavities or on flat horizontal surfaces of the
parts as well as the solvent film remaining on all surfaces of clean parts
as they leave the cleaner. If the workload is withdrawn slowly and allowed
to dwell in the freeboard area (if needed), then the solvent film and much
of the pooled solvent can evaporate before the workload is withdrawn. A
significant portion of this evaporated solvent in the freeboard area will
sink back into the vapor layer or be condensed on the coils and return to
the cleaner. If, however, the workload is withdrawn quickly, most liquid
solvent will not evaporate from the parts until after they are withdrawn
from the cleaner. It is very difficult to remove parts slowly by manual
operation. Generally, manually operated cleaners will have high workload
losses, and these losses will dominate other losses from the machine.
A summary of the available data on working emission rates
(i.e., diffusion/convection and workload losses combined) is presented in
y
Table 3-2. The emission rates range from 0.063 Ib/ft /hour to
2
0.775 Ib/ft /hour, with most data in the range of about 0.1 to
2
0.3 Ib/ft /hr. The large variability in the data is due to the wide range
of operating parameters during the tests. Unlike idling emissions, which
are more a factor of the machine design, workload emissions are largely a
factor of the operating parameters previously discussed in this section.
The speed of parts movement in many of the tests is unknown. All of these
test were performed using electric hoists for parts entry and removal. Test
results with manually operated machines would be significantly higher
because it is difficult to impossible for a human operator to consistently
achieve the low workload related losses exhibited by hoists. As stated
3-35
-------
TABLE 3-2. SUMMARY OF EMISSION TESTS OH WORKING OTVC's
Conditions
Primary
Test Cleaner Cleaner Air Speed Condenser
# Solvent Size (m ) Make (FPM) Temp.( F)
1 1,1,1-TCA 1.8 Oetrex calm
2 1,1,1-TCA 1.8 Detrex 130
3 1,1,1-TCA 1.8 Oetrex 160
4 1,1,1-TCA 1.4 AutoSonics --
5 MC 1.2 Crest --c
6 MC 1.2 Crest --c
7 1.1,1-TCA 0.9 AutoSonics --c
8 1,1,1-TCA 0.9 AutoSonics --c
9 1,1.1-TCA 0.9 AutoSonics --c
10 CFC-113 0.9 AutoSonics --c
11 CFC-113 0.9 AutoSonics --c
12. CFC-113 0.9 AutoSonics --c
13° CFC-113 Branson
H MC blend 0.4 AutoSonics
15 MC 0.4 AutoSonics
16 CFC-113 0.4 AutoSonics
17 MC blend 0.4 AutoSonics
18 1,1,1-TCA 0.4 AutoSonics
19 TCE 0.4 AutoSonics
20 HC blend 0.4 AutoSonics
21 MC 0.4 AutoSonics
22 CFC-113 0.4 AutoSonics
23 MC blend 0.4 AutoSonics
24 1,1,1-TCA 0.4 AutoSonics
25 TCE 0.4 AutoSonics
j^FBR = freeboard ratio.
"Working" emissions include diffusion, convection, and
csolvent transfer losses or downtime losses.
^Information unknown or not available.
_ ^
30
30
30
30
30
30
30
30
30
30
30
30
workload losses
Constant cycling of parts into and out of machine and use of perforated
exit from machine account for elevated emission number.
]_c
c
c
50
70
85
40
50
70
60
70
70
70
70
70
70
70
70
70
70
70
70
as described
metal basket
FBRa
0.75
0.75
0.75,
0.83
0.7?
1.0
0.75
0.75
0.75
0.75
0.75
0.75
.0
.0
.0
.0
.0
.0
in Sections 3.
that retained
Emission
Rate
Ob/ftVhr) Reference
0.099
0.173
0.233
0.063
0.186
0.354
0.100
0.140
0.170
0.090
0.110
0.186
0.775
0.220
0.180
0.165
0.125
0.112
0.080
0.175
0.145
0.132
0.100
0.092
0.065
3.1 and 3.3.
significant
5
5
5
6
7
7
3
3
3
3
3
3
8
9
9
9
9
9
9
9
9
T
9
9
9
2, but not leaks,
solvent upon
-------
above, the speed of the parts can directly affect the emissions from a
cleaner. Furthermore, these tests also included a wide range of room air
speeds, which can also affect emission rates. In contrast, the tests of
idling rates did not include different draft speeds. Finally, the tests in
Table 3-2 did not include lip exhausts, which would greatly increase
emissions. A more complete discussion of the effects of operating
parameters on emission rates is presented in Chapter 4.
3.3.2.2 In-line Cleaners. The principal sources of workload emissions
from in-line cleaners are presented in Figure 3-14. Many of the losses are
similar to the losses from OTVC's. Since in-line systems are automated, the
workload losses are less on a per part basis than in a manually operated
OTVC. However, due to the large volume of parts cleaned in an in-line
system, overall losses are typically higher from in-line cleaners than from
OTVC's.
The loss due to turbulence at the air/solvent vapor interface
(air/solvent interface with in-line cold cleaners) caused by part entry and
exit is generally less for in-line cleaners than manually operated OTVC's
because automated parts handling allows better control of the speeds of
parts entry and exit. However, if the conveyor speed is too high,
considerable turbulence will be generated, and parts may exit the cleaner
wet with solvent. The piston effect is also lessened since in-line machines
have large air/solvent vapor interfaces (air/solvent interface with in-line
cold cleaners) relative to the size of the parts and baskets. In general,
States that have solvent cleaner regulations limit the conveyor speed to 11
feet per minute (fpm).
3-37
-------
Solvent loss due to vapor line fluctuation is not a significant problem
for in-line vapor cleaners as with OTVC's. Since there is a constant flow
of parts into in-line vapor cleaners, the heat balance of the machine can be
adjusted to compensate for the constant thermal shock. This practice would
tend to limit vapor line fluctuation in these machines.
During parts cleaning, additional losses can occur if spraying is
employed. Spraying is done from either fixed nozzles, spray wands or
rotating arms. The solvent spray can cause turbulence within the cleaner
and thereby increase emissions, although the enclosure around in-line
machines would help minimize loss to the atmosphere. The configuration of
entry and exit openings will influence the amount of loss from turbulence
inside the machine. If the spray pressure is toe high, splashing of the
solvent against the parts, parts basket, or wall of the cleaner can also
increase emissions. Fixed or rotating spray nozzles should be mounted so
that spraying occurs only beneath the vapor zone. For in-line cold
cleaners, spraying should occur only at a downward angle into the machine
unless the spray section is baffled to effectively shield air/solvent
interface from the effects of the spray. Some manufacturers have developed
cleaners that have high pressure spray zones completely segregated from the
air/solvent vapor interface. These machines are discussed in Chapter 4.
As parts are removed from the cleaner, more disturbances of the
air/solvent vapor or air/solvent interface can occur. Again, the speed of
the parts movement can directly affect the amount of solvent loss. The
effect of part movement rate on emission rates is discussed in Chapter 4.
Again, the majority of this loss is vapor entrainment. If parts are
extracted rapidly, solvent vapor will be entrained behind the workload and
pulled out of the cleaner.
3-38
-------
Another source of loss during part removal is liquid dragout. This
includes liquid solvent pooled in cavities or on flat horizontal surfaces of
parts as well as the solvent film remaining on all surfaces of clean parts
as they leave the cleaner. As discussed in Section 3.3.2, the speed of part
removal can affect these losses. Some in-line cleaners include a drying
tunnel to allow for evaporation of solvent before parts exit the cleaner.
Many in-line cleaners also have an exhaust system. This exhaust
system (for an example see Figure 3-14) can increase solvent consumption.
If solvent in the exhaust is not controlled by a carbon adsorber before
being vented to the atmosphere, overall solvent emissions will increase.
3.3.2.3 Cold Cleaners. Workload related losses from cold cleaners are
primarily due to carry-out (and subsequent evaporation) of liquid solvent on
parts being removed from the machine. Carry-out losses may be substantially
reduced by allowing longer drainage time, and by tipping parts to drain
solvent-filled cavities before removal from the cleaner.
Other sources of solvent loss during cold cleaning are agitation and
spraying. Agitation can increase evaporation from the solvent bath by
increasing the effective air/solvent interface area. The amount of solvent
loss depends on the rate of agitation. In the case of carburetor cleaners,
the water layer over the solvent bath minimizes the loss from increased
turbulence. Spraying can increase solvent evaporation by exposing more
solvent to the air. The amount of solvent loss from spraying depends on the
spray pressure (which influences turbulence and splashing).
3-39
-------
3.3.3 Other Losses
In addition to losses attributable to the solvent cleaner when the
machine is idling (i.e., turned on and ready to operate) or working
(i.e., cleaning a workload), there are several other loss mechanisms that
contribute to overall losses from an organic solvent cleaner. These include
leaks, start-up losses, filling/draining losses, shutdown/downtime losses,
wastewater losses, distillation losses, and losses due to solvent
decomposition/waste solvent storage. The magnitude of these losses relative
to total losses is dependent on machine design and integrity and operating
techniques. For example, poor technique during filling and emptying of the
cleaner can cause spills that could amount to a large portion of overall
losses from an otherwise well operated and maintained machine. Similarly, a
leak that goes undetected and uncorrected can also be a large source of
emissions. A brief discussion of these other losses is presented below.
3.3.3.1 Downtime Losses. Downtime losses are defined as solvent loss
when the heat to the sump is turned off and the machine is not operated.
The losses are due to evaporation of solvent from the liquid solvent
surface and subsequent diffusion into the ambient air. These losses can be
slowed through use of a tight fitting cover during downtime. However, even
with covers in place, the more volatile halogenated solvents will evaporate
at significant rates. Relative evaporation rates of the halogenated
solvents are presented in Table 3-3. Equipment vendor estimates of downtime
losses range from 0.03 Ib/ft2/hr to 0.07 Ib/ft2/hr, comparable to the low
end of idling loss rates. Losses will be greatest from machines using
3-40
-------
TABLE 3-3. HALOGENATED SOLVENT EVAPORATION RATES
Solvent
TCE
PCE
1,1,1-TCA
MC
CFC-113
Relative
Evaporation Rate
84
39
100
147
170
(CC14 - 100)
Reference 10.
3-41
-------
solvents with a higher vapor pressure, such as MC, CFC-113, or solvent
blends made with MC or CFC-113.
3.3.3.2 Lfiiks.. Loss of solvent through leaks can occur continuously
(depending on where the leak is located), whether the machine is turned on
or off. Leaks can result from manufacturing defects or from machine use.
They can occur from piping connections, cracks in the machine or tank, and
gasketed portholes or viewing windows. Often leaks are difficult to detect
since the solvent will evaporate quickly when it reaches the atmosphere and
may not leave telltale drips or wet areas. Since solvent has a low surface
tension, it can escape through cracks that may not be easily visible. These
characteristics magnify the chance of leaks becoming a serious source of
solvent loss. Many manufacturers leak test their machines before they are
sold, but cracks can occur during shipping. If not detected and repaired,
leaks can become a major source of solvent loss.
3-3-3-3 Filling/Draining Losses. The loss of solvent during filling
and emptying of the solvent cleaner can be a major contributor to overall
emissions if not properly performed. Open handling procedures, such as
manual filling or emptying machines using open buckets or drums, will cause
significant solvent loss and operator exposure. This loss will increase if
a large amount of splashing occurs during filling. If solvent is spilled
during filling or draining, the operator may be subject to Comprehensive
Environmental Response, Composition, and Liability Act (CERCLA) regulations
requiring the notification of all spills above reportable quantities.
3-42
-------
3.3.3.4 Wastewater Losses. Water separators are typically minor
sources of solvent loss on vapor cleaners. The solvent loss occurs when the
water is decanted from the separator containing a slight amount of solvent
(solvents are slightly soluble in water). Water separators are used to
recover solvent from the solvent/water mixture that condenses at the primary
chiller or at the refrigerated freeboard device. Freeboard refrigeration
devices may increase wastewater loss, if not properly designed, since they
condense water vapor from the atmosphere in addition to solvent. However,
if a separator is correctly designed, operated and maintained, little
solvent will be lost. Wastewater impacts due to the use of a carbon
adsorber as a control device to recover solvent are discussed in Chapter 4.
3.3.3.5 Start-up/ Shutdown Losses. The losses that occur during the
transition time from when a vapor solvent cleaner is turned on or off to the
time when equilibrium is achieved are called start-up and shutdown losses.
Start-up losses are due to pump out of solvent-laden air within the
machine after the sump heat has been activated and as the solvent vapor
layer is being established. One estimate of start-up losses from a typical
12
vapor cleaner is 3 gallons of solvent per cycle. However, the amount of
loss from a cleaner depends on the cleaner size and design.
Shut-down losses are due to evaporation of hot liquid solvent from the
sump (after the heat has been turned off and the vapor layer has collapsed)
and subsequent diffusion of solvent vapor from the machine. If not
controlled, shut-down losses will be significant since the solvent in the
machine is near the boiling point at the beginning of the shut-down period.
3-43
-------
3.3.3.6 Distillation Losses/Sludge Disposal. Losses occur when spent
solvent is regenerated through onsite distillation for reuse. Solvent lost
during this process stems from evaporation during transfer to and from the
distillation unit or, if a piping system is used, from leaks in the
equipment. Solvent may also evaporate from distillation sludge or spent
solvent that is removed for disposal.
3.3.3.7 Solvent Decomposition Losses. Certain solvents and blends
contain stabilizers which prevent the mixture from turning acidic after
reacting with water (where water/solvent contact occurs). If solvent is not
properly monitored but allowed to become acidic, the solvent will have to be
discarded. Dangerous fumes (chlorine gas, hydrochloric acid) can be emitted
from solvent decomposition. Emissions could occur during handling and
disposal of the solvent. This solvent would be subject to hazardous waste
guidelines under RCRA.
3.4 TYPICAL EMISSION SCENARIOS FOR VAPOR CLEANERS
Idling emission rates and working emission rates can vary considerably
from operation to operation depending on cleaning machine design, types of
solvent, and operating environment. If the five halogenated solvents are
used in identical machines, measured idling emission rates will vary
somewhat among the solvents. For example, CFC-113 and MC tend to have
higher idling losses than the others. However, machines using these
solvents are designed to compensate for this, usually by employing
lower primary condensing temperatures. Moreover, working losses from
3-44
-------
identical machines also show differences by solvent, although the order may
be different from that observed in idling emission rate comparisons. The
emission rate differences due to solvent characteristics appear to be
relatively small and are overshadowed by other factors such as: the amount
of room draft the cleaner is exposed to, the type of workload cleaned, hours
of operation, and operating practices. Therefore, no attempt is made in
this document to define emission rates on a solvent specific basis. The
"typical" emission rates developed in this section are meant to be
representative of cleaners using any one of the five solvents.
The operating schedule defines the relative amounts of time the machine
spends in the idling, working (i.e., cleaning) and downtime modes. For
example, a cleaner that is in the working mode for most of the day would
emit more than the same cleaner in the idling mode for most of the day.
This is due to the fact that the working emission rate for a cleaner is
higher than the idling emission rate.
The relative contribution of each emission type (idling, workload,
leaks, start-up/shut-down, downtime, etc.) influences the effectiveness of
control techniques selected to reduce overall emissions, and thereby solvent
consumption, from a cleaner. If the majority of overall emissions are due
to idling and downtime losses, then control techniques that reduce those
emission types would be relatively more important in determining overall
effectiveness of control. Conversely, if the machine is in the working mode
most of the time, then controls that reduce workload emissions would
dominate the overall effectiveness of all controls.
An example of the variation in solvent cleaner emissions with operating
schedule is shown in Table 3-4 for a hypothetical OTVC. In-line vapor
3-45
-------
cleaner emissions would vary less with operating schedule compared to an
OTVC since in-line cleaners presumably clean a continuous stream of parts
and, thus, have few idle periods. The estimates of annual solvent emissions
in Table 3-4 are meant to represent typical, well-run manual operations and
are based on the following parameters:
• An OTVC with no additional controls, some room drafts, 0.75 freeboard
ratio, and a primary condenser operating at approximately 75°F.
• Idling losses of 0.15 Ib/ft2/hr (within the range in Table 3-1)
• Working losses of 0.4 Ib/ft2/hr
§ Downtime losses of 0.03 Ib/ft2/hr (from Reference 2)
• OTVC size of 8.6 ft2 (from general vendor information)
• Assumed daily operating schedule A of 2-hour working, 6-hour idling,
and 16-hour downtime for 250 days per year (24-hour downtime for
105 days per year)
• Assumed operating schedule B of 12-hour working, 4-hour idling, and
8-hour downtime for 250 days per year (24-hour downtime for 105 days
per year).
In this example, wastewater losses, leaks, start-up/shutdown losses and
solvent/waste solvent transfer losses are not included. These sources can
be significant, especially in poorly designed, maintained or operated
cleaners.
3-46
-------
TABLE 3-4. EXAMPLE OF OPERATING SCHEDULE INFLUENCE
ON SOLVENT CLEANER EMISSIONS
SolventbEmission Rate (lb/yr)a
Emission Type Schedule A Schedule B
Idling
Workingd
Downtime
TOTAL
2,010 (36%)
1,790 (33%)
1.720 (31%)
5,520 (100%)
1,340 (10%)
10,730 (81%)
1.180 f 9%)
13,250 (100%)
[JBased on OTVC size of 8.6 ft2 (0.8m2).
Assumes daily operation of 2-hour working, 6-hour idling, and 16-hour
downtime.
Assumes daily operation of 12-hour working, 4-hour idling, and 8-hour
.downtime.
Working losses include idling loss and workload related losses (as described
in Sections 3.3.1 and 3.3.2, respectively).
Other emission sources, such as leaks and startup/shutdown losses, have not
been included in this example but could be significant sources of solvent
loss.
3-47
-------
3.5 REFERENCES
l' r^rnndum from Pandullo» R- F-, Radian Corporation, to D. A. Beck
EPA/CPB. February 15, 1989. Estimation of nationwide number of '
nalogenated solvent cleaners and halogenated solvent usage.
2. Letter and attachments from Delta Sonics to D.A. Beck, EPA/CPB
February 1988. 6 pages. Estimation of freon solvent usage in'open top
series Delta Sonics degreasers.
3. Cool It to Cut Degreasing Cost. American Machinist. November 1982.
4. Trip report. Pandullo, R. F., Radian Corporation, submitted to
DA. Beck, EPA/CPB, Research Triangle Park, NC. January 1989. Summary
of visit to Allied Corporation, Buffalo Research Facility.
5. Memorandum from Goodrich, J., Detrex Corporation, to L. Schlossberg
Detrex, Inc. Degreaser emissions control test report.
6. Trip report. Irvin, R., GCA/Technology Division, submitted to
D.A. Beck, EPA/CPB, Research Triangle Park, NC. June 14, 1979
Summary of visit to Autosonics, Incorporated.
7. Suprenant, K. S. and D. W. Richards (Dow Chemical Company). Study to
Support New Source Performance Standards for Solvent Metal Cleaning
Operations. Prepared for U.S. Environmental Protection Agency
Research Triangle Park, NC. April 1976. Contract No. 68-02-1329
Task Order No. 9.
8. Letter and attachments from Polhamus, R. L, Branson Ultrasonics
Corporation, to P. A. Cammer, Halogenated Solvents Industry Alliance
February 10, 1988. Automated hoist test data.
9. Reference 4.
10. American Society for Testing and Materials (ASTM) . Cold cleaning with
halogenated solvents. Philadelphia, Pa. July 1966. p. 9.
11. Reference 2.
12. Trip report. Miller, S. J., Radian Corporation, submitted to
D.A. Beck, EPA/CPB. October 19, 1988. Summary of visit to Unique
Industries, Sun Valley, CA.
3-48
-------
4.0 EMISSION CONTROL TECHNIQUES
4.1 INTRODUCTION
As discussed in detail in Chapter 3, there are several significant
sources of solvent loss from cleaners using halogenated solvents. To
achieve low emissions during solvent cleaning, owners or operators must
consider minimizing loss from each source. Good control can be achieved
through use of a cleaning machine incorporating solvent saving features and
through implementation of sound operating practices.
Presented in this chapter are solvent control strategies covering both
machine design and operating practices. Table 4-1 presents a chapter
outline and lists the control techniques studied. For both open top vapor
cleaners (OTVC's) and in-line cleaners, there are separate sections devoted
to diffusion/convection controls, workload related controls, and control of
other fugitive emission sources. Following these sections is a discussion
concluding what design elements and operating practices should be
incorporated to achieve a very well controlled solvent cleaning operation.
Finally, the chapter ends with remarks about alternatives to solvent
cleaning with the five common halogenated solvents.
4.2 OPEN TOP VAPOR CLEANERS
As discussed in Chapter 3, OTVC's utilize a heating system to boil
liquid solvent which creates a solvent vapor zone for cleaning. The
primary condenser contains the vapor zone within the cleaner.
4-1
-------
TABLE 4-1. SUMMARY OF SOLVENT CLEANER CONTROL TECHNIQUES
Cleaner Control Technique Reference Section
OTVC:
Interface Emission Controls; 4>2.i
Covers 4<2.i i
Freeboard Refrigeration Devices 4212
Refrigerated Primary Condensers 4213
Increased Freeboard Ratio 4214
Reduced Room Draft/Lip Exhaust Velocities 4215
Enclosed Design 4216
Carbon Adsorption 4^2 1 7
Workload Emission Controls; 4 2.2
Mechanically Assisted Parts Handling 4.2.2.1
Reduced Parts Movement Speed 4.2!2!2
Carbon Adsorption 4217
Hot Vapor Recycle/Superheated Vapor 4.2.2.3
Proper Operating and Maintenance Practices: 4.2.3
IN-LINE
Interface Emissions Controls: 4.3.1
Minimize Entrance/Exit Openings 4.3.1.1
Carbon Adsorption 4.3.1.2
Freeboard Refrigeration Devices 4.3.1.3
Workload Emissions Controls: 4.3.2
Carbon Adsorption 4.3.1.2
Drying Tunnels 4.3'.2.l
Rotating Baskets 4.3.2^2
Hot Vapor Recycle/Superheated Vapor 4.3!2Is
Proper Operating and Maintenance Practices 4.3.3
4-2
-------
Standard OTVC models range in size from 2.2 to 48 square feet (0.2 to
4.5 square meters) in air/solvent vapor interface area, although larger
custom made units are in use. A typical OTVC has a 0.75 freeboard ratio, a
water-cooled primary condenser, a cover used during downtime, and an
external water jacket to cool the cleaner walls (see Figure 3-1).
Applicable control techniques vary according to the size, design,
application, and operation of the OTVC. In general, the emissions
reduction efficiency of the various control options depends upon the
fraction of time that the OTVC is idling versus processing work since each
control has different effects on these emission mechanisms.
The control techniques for OTVC's presented in the following sections
include covers, reduced room drafts, refrigerated freeboard devices,
refrigerated primary condensers, raised freeboards, carbon adsorbers,
electric or mechanically assisted parts handling/reduced part movement
speeds, enclosed designs, and selected operating and maintenance practices.
A summary of all OTVC emission test data is presented in Tables 4-2 and
4-3. Tests on idling machines are included in Table 4-2, while working
machine data are included in Table 4-3. All idling tests are numbered
using an "I" prefix. All of these tests were performed by companies that
either manufactured solvent cleaning equipment or sold solvents. No
standard test methods were used. Each company established its own test
procedure. The data and test procedures have been reviewed by EPA and
appear to have given valid, repeatable results. In some cases, the test
facilities have been visited by EPA personnel. All OTVC test data in
Table 4-3, unless otherwise mentioned, are from machines employing
automated mechanical systems for parts handling. In many cases, the speed
4-3
-------
TABLE 4-2. SUMMARY OF AVAILABLE TESTS - IDLING OTVC's
Test
1-1
1-2
1-3
I-A
1-5
1-6
1-7
1-8
1-9
1-11
1-12
1-13
1-14
1-15
1-16
1-17
1-18
1-19
1-20
Tested
* Control
AFC (PC850F)
BFC (PC850F)
BFC (PCIJ50F)
BFC (PC@70F)
BFC (PC085F)
BFC (PC940F)
BFC (PC850F)
BFC (PC870F)
PC-70 F to 40 P
PC-85 F to 50 F
PC-85 F to 50 F
BFCt.Li.pExh PgSOF
BFC&LlpExh P870F
BFClLlpExh P885F
LIP EXH (PCgSOF)
LIP EXH (PC870F)
LIP EXH (PC885F)
FBR: 0.75->1.0
FBR: 0.75->1.0
Solvent
Freon-TF
Freon-TF
TCA
TCA
TCA
CFC-113
CFC-113
CFC-113
CFC-113
TCA
TCA
TCA
TCA
TCA
TCA
TCA
TCA
TCA
TCA
Cleaner
Size Cleaner
(ft ) Make
3.3
3.2
9.7
9 7
9 7
9.7
9.7
9.7
9.7
9.7
9.7
9.7
9.7
9.7
9.7
9.7
9.7
8.0
8.0
Delta Son Ic 3
Delta Sonic 3
Auto-Sonlcs
Auto-Sonlcs
Auto-Sonlcs
Auto-Sonlcs
Auto-Sonlcs
Auto-Sonlcs
Auto-Sonlcs
Auto-Sonlcs
Auto-Sonlcs
Auto-Sonlcs
Auto-Sonlcs
Auto-Sonlcs
Auto-Sonlcs
Auto-Sonlcs
Auto-Sonlcs
Detrex
Detrex
Baseline
Air
Speed
(fpm) Cover
30 open
30 open
LE OFF none
LE OFF none
LE OFF none
LE OFF none
LE OFF none
LE OFF none
LE OFF none
LE OFF none
LE ON none
LE ON none
LE ON none
LE ON none
LE ON none
LE ON none
LE ON none
calm none
30-100 none
FBR
1.0
1.0
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.75
0.75
Controlled
Air
Freeboard Emission Speed Freeboard Emission Control
Refrigeration (Ib/ft2/hr) (fpm) Cover FBR Refrigeration (lb/ftZ/hr) Efficiency* Reference
off
off
off
off
off
off
off
off
off
off
off
off
off
off
off
off
off
off
off
0.060
0.060
0.087
0.120
0.143
0.062
0.094
0.169
0.169
0.143
0.211
0.171
0.190
0.211
0.171
0.190
0.211
0.051
0.272
30
30
LE OFF
LE OFF
LE OFF
LE OFF
LE OFF
LE OFF
LE OFF
LE OFF
LE ON
LE OFF
LE OFF
LE OFF
LE OFF
LE OFF
LE OFF
off
off
open
open
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
1.0
1.0
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
1.0
1.0
AFC
BFC
BFC
BFC
BFC
BFC
BFC
BFC
off
off
off
BFC
BFC
BFC
off
off
off
off
off
0.049
0.050
0.040
0.050
0.063
0.055
0.070
0.072
0.062
0.087
0.171
0.040
0.050
0.063
0.087
0.120
0.143
0.054
0.167
18Z
17Z
541
581
56Z
11X
26Z
57X
63X
39Z
19Z
77Z
74Z
70Z
49X
37Z
32Z
-6Z
39Z
1
1
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
3
3
BFC
th.
•These control efficiency values refer to the percent control of Idling emission (I.e.. diffusion and convection losses) only.
-------
TABLE 4-3. SUMMARY OF AVAILABLE TESTS - WORKING OTVC's
cn
Baseline
Cleaner
Tested Size Cleaner
Test f Control Solvent (m ) Make
1
2
3
4
5
6
7
B
9
10
11
12
13
U
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
AFC TCA
AFC TCA
AFC TCA
AFC TCA
AFC TCE
AFC TCE
AFC(spray loss) Freon TF
BFC
BFC TCA
BFC TCA
BFC TCA
BFC TCA
BFC MC
BFC MC
BFC (P950F) TCA
BFC (P870F) TCA
BFC (P985F) TCA
BFC (P040F) CFC-113
BFC (P850F) CFC-113
BFC (P@70F) CFC-113
(BFCtLlpExh.PgSOF TCA
(BFClLlpExh,Pg70F TCA
(BFClLlpExh,P885F TCA
DWELL TIME Freon TF
HOIST: 11-3 Freon TF
HOIST: 20-10*
(LIP EXH (P650F) TCA
(LIP EXH (P870F) TCA
(LIP EXH (P£85F) TCA
PC-70 F to 40 F CFC-113
PC-85 F to 50 F TCA
PC-85 F to 50 F TCA
PC-70 F to 50 F TCA
PC-50 F to 40 F CFC-113
Blpart Ing cover TCA
Blpart ing cover TCA
1.8
1.8
1.8
1.4
0.3
1.8
1.8
1.8
1.4
1.2
1.2
0.9
0.9
0.9
0.9
0.9
0.9
0.9
0.9
0.9
0.3
0.3
0.9
0.9
0.9
0.9
0.9
0.9
0.9
0.9
1.8
1.8
Detrex
Detrex
Detrex
AutoSonlcs
DeltaSonlcs
Detrex
Detrex
Detrex
AutoSonlcs
Crest
Crest
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
DeltaSonlcs
DeltaSonlcs
Branson
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
Detrex
Detrex
Air
Speed
(fpm)
calm
130
160
calm
calm
30
130
160
LE OFF
LE OFF
LE OFF
LE OFF
LE OFF
LE OFF
LE ON
LE ON
LE ON
1.0
1.0
1.0
LE ON
LE ON
LE ON
LE OFF
LE OFF
LE ON
LE OFF
LE OFF
30
100
Cover
none
none
none
none
none
none
none
none
none
manual
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
Secondary Emission
FBR Chiller (lb/ft /hr)
0.75
0.75
0.75
1.0
0.75
0.75
0.75
0.83
0.75
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
1.0
1.0
1.0
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.75
0.75
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
0.099
0.173
0.233
0.063
4.30E+06 g/mo
6.20E+06 g/mo
Air
Speed
(fpm)
calm
130
160
0.0093 Ib/ft2/cy
0.099
0.173
0.233
0.063
0.186
0.354
0.100
0.140
0.170
0.090
0.110
0.186
0.219
0.25
0.277
0.014 Ib/cy
0.039 Ib/cy
0.775
0.219
0.25
0.277
0.186
0.160 t
0.277
0.140
0.110
0.099
0.121
calm
130
160
LE OFF
LE OFF
LE OFF
LE OFF
LE OFF
LE OFF
LE OFF
LE OFF
LE OFF
1.0
1.0
LE OFF
LE OFF
LE OFF
LE OFF
LE OFF
LE ON
LE OFF
LE OFF
30
100
Cover
none
none
none
none
none
none
none
none
none
manual
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
blpart
blpart
Controlled
Secondary Emission Control
FBR Chiller (lb/ft /hr) Efficiency*
0.75
0.75
0.75
1.0
0.75
0.75
0.75
0.83
0.75
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
1.0
1.0
1.0
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.75
0.75
AF
AF
AF
AF
AF
AF
AF
BF
BF
BF
BF
BF
BF
BF
BF
BF
BF
BF
BF
BF
BF
BF
BF
none
none
none
none
none
none
none
none
none
none
none
none
none
0
0
0
0
.082
.105
.116
.040
3.60E+06 g/mo
3.50E+06 g/mo
0.0079 Ib/ft2/cy
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.059
.091
.150
.011
.112
.254
.053
.070
.082
.075
.080
.110
.053
.070
.082
.008 Ib/cyc
.008 Ib/cyc
.555
.100
.140
.160
.090
.100
.219
.100
.090
.061
.071
18X
39X
50X
37X
16X
44X
15X
41X
47Z
36X
82X
40X
28X
47X
50X
52X
17X
27X
41X
76X
72X
70X
46X
SIX
28X
54X
44X
42X
521
38X
21X
29X
18X
38X
41X
Reference
4
4
4
5
6
6
7
8
4
4
4
5
3
3
2
2
2
2
2
2
2
2
2
7
7
9
2
2
2
2
2
AFC - Above-Freezing Freeboard Refrlgeratloni BFC » Below-Freezing Freeboard Refrigeration! LE - Lip Exhausti PC — Primary Condenser (e.g.
primary condenser temperature was 50 F)i unk • Information unknown or not available.
PCgSOF means the
*These control efficiency values refer to percent control of working losses (I.e., diffusion/convection losses plus workload related losses).
control of other possible emission sources such as: leaks, startup/shutdown losses, solvent transfer losses, and downtime losses.
The relatively high emission rates were due to the configuration of the parts basket (I.e., a large horizontal surface area) and the
constant cycling of parts (i.e., no time was allowed for the parts/basket to reach the temperature of the solvent vapor).
They do not reflect
-------
TABLE 4-3. SUMMARY OF AVAILABLE TESTS - WORKING OTVC's
CTi
Baseline
Tested
Test 1 Control
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Blpart Ing. cover
Biparting cover
Blprtng cvrlAFC
Blprtng cvrlAFC
Blprtng cvrSAFC
Blprtng cvriAFC
Blprtng cvrlBFC
Blprtng cvrlBFC
Blprtng cvriBFC
Blprtng cvrlBFC
FBR: 0.75->1.0
FBR: 0.75->1.0
FBR: 0.75->1.0
FBR: 0.75->1.0
FBR: 0.75->1.0
FBR: 0.75->1.0
FBR: 1.0->1.25
FBR: 1.0->1.25
FBR: 1.0->1.25
FBR: 1.0->1.25
FBR: 1.0->1.25
FBR: 1.0->1.25
Draft 160 -calm
Draft 130-calm
Solvent
TCA
TCA
TCA
TCA
TCA
TCA
TCA
TCA
TCA
TCA
MC blend
MC
CFC-113
MC blend
TCA
TCE
MC blend
MC
CFC-113
MC blend
TCA
TCE
TCA
TCA
Cleaner
Size Cleaner
(n ) Make
1.8
1.8
1.8
1.8
1.8
1.8
1.8
1 .8
1.8
1.8
0.4
0.4
0.4
0.4
0.4
0.4
0.4
0.4
0.4
0.4
0.4
0.4
1.8
1.8
Detrex
Detrex
Detrex
Detrex
Detrex
Detrex
Detrex
Detrex
Detrex
Detrex
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
AutoSonlcs
Detrex
Detrex
Air
Speed
(fpm)
130
160
30
100
130
160
30
100
130
160
30
30
30
30
30
30
30
30
30
30
30
30
160
130
Cover
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
Secondary
FBR Chiller
0.75
0.75
0.75
0.75
0.75
0.75
0.75
0.75
0.75
0.75
0.75
0.75
0.75
0.75
0.75
0.75
1.0
1.0
1.0
1.0
1.0
1.0
0.75
0.75
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
none
Emission
Ub/ft /hr)
0.173
0.233
0.099
0.121
0.173
0.233
0.099
0.121
0.173
0.233
0.220
0.180
0.165
0.125
0.112
0.080
0.175
0.145
0.132
0.100
0.092
0.065
0.233
0.173
Air
Speed
(fpm)
130
160
30
100
130
160
30
100
130
160
30
30
30
30
30
30
30
30
30
30
30
30
30
30
Cover
blpart
blpart
blpart
blpart
blpart
blpart
blpart
blpart
blpart
blpart
none
none
none
none
none
none
none
none
none
none
none
none
none
none
Controlled
Secondary
FBR Chiller
0.75
0.75
0.75
0.75
0.75
0.75
0.75
0.75
0.75
0.75
1.0
1.0
1.0
1.0
1.0
1.0
1.25
1.25
1.25
1.25
1.25
1.25
0.75
0.75
none
none
AFC
AFC
AFC
AFC
BFC
BFC
BFC
BFC
none
none
none
none
none
none
none
none
none
none
none
none
none
none
Emission
(Ib/ft /hr)
0.090
0.109
0.054
0.070
0.083
0.105
0.055
0.064
0.080
0.078
0.175
0.145
0.130
0.100
0.090
0.065
0.165
0.135
0.122
0.092
0.083
0.059
0.099
0.099
Control*
Efficiency
48X
53*
45X
42X
52X
55X
44X
47Z
S4X
67X
20X
19X
21X
20X
20X
19X
6X
7X
8X
8X
10X
9X
58X
43*
Reference
4
4
4
4
4
4
4
4
4
4
10
10
10
10
10
10
10
10
10
10
10
10
^
4
AFC - Above-Free zing Freeboard Refrigeration: BFC - Below-Freezing Freeboard Refrigeration: LE - Lip Exhaust.
•These control efficiency values refer to percent control of working losses (I.e., diffusion/convection losses plus workload related losses). They do not reflect
control of other possible emission sources such as: leaks, startup/shutdown losses, solvent transfer losses, and downtime losses.
-------
of parts movement is unknown; however, it was likely 11 fpm or less in all
cases. In almost all cases, workloads used for these tests can be
described as inherently producing low carryout losses. Therefore, emission
rates would likely be higher from machines in regular industrial
applications. Inferences on control efficiencies that can be drawn from
these data are discussed in the following sections.
4.2.1 Controls for Interface Emissions
4.2.1.1 Covers. Covers are used on OTVC's to eliminate drafts within the
freeboard and reduce diffusion losses. Covers can be manually operated,
electrically powered (some powered models are automated to work with the
cleaning cycle). Some typical covers are presented in Figure 4-1.
Roll-top covers are typically plastic (mylar). In addition to roll-top
covers, OTVC covers include flat covers made out of mylar or metal.
Manual covers are normally provided as standard equipment. These
covers are intended to reduce OTVC emissions during idle time and periods
of non-use (i.e., downtime). Manual covers should fit well and should be
operated carefully to ensure that they do not become bent or otherwise
damaged. If a lip exhaust is used, the cover should fit between the
solvent vapor and the exhaust inlet. Manual covers can be flat-hinged,
sliding, or roll-top. Hinged covers are not recommended because opening
and closing these covers can disturb the vapor layer and unnecessarily
expose the operator. If a flat-hinged cover moves too quickly, it can
cause turbulence that can disturb the air/solvent vapor interface and
increase emissions. Flat covers that slide horizontally off the machine
reduce the disturbance to the vapor layer.
4-7
-------
oo
A. Roll Top Cover
(manual)
B. Bi Parting Roll Top Cover
(power)
Figure 4-1. Typical OTVC Covers
$
r-
at
co
-------
To minimize disturbance of the air/solvent vapor interface, roll-top
plastic (mylar) covers, canvas curtains, and guillotine (biparting) covers
which close horizontally can be installed. Biparting covers can be made to
close around the cables holding parts baskets when the basket is inside the
cleaner. This affords complete enclosure during the cleaning phase.
Powered biparting covers are usually operated by push button control with
an automatic shut-off and are either pneumatically or electrically driven.
The most advanced biparting covers are automated to coordinate cover
movement with the movement of an automated parts handling system. This
design minimizes the period of time the cover is opened, only allowing for
part entry and exit from the cleaner. Powered biparting covers, which are
closed during the cleaning cycle, reduce both idling and working losses due
to diffusion by minimizing air drafts which disturb the air/solvent vapor
interface. On larger machines, it is generally desirable to have powered
(i.e., mechanically assisted) or automated covers.
Four tests were available for an automatic cover that was closed
during most of the cleaner operation (Table 4-3, Tests 35, 36, 37, and 38).
In these tests a biparting roll-top cover that was closed 79 percent of the
time (275 seconds out of the 350 second OTVC cycle) was evaluated. Without
2
the automated cover, working emission rates varied from 0.10 Ib/ft /hr
o
(under calm air conditions) to 0.23 Ib/ft /hr (160 fpm room drafts). With
an automated cover in use, working emission rates decreased to between 0.06
Ib/ft2/hr (calm) to 0.11 Ib/ft2/hr (160 fpm). This corresponds to working
loss reductions of 38 percent (calm) to 53 percent (160 fpm). As expected,
covers are more effective at higher air draft velocity. The effect of
reduction of room drafts on emissions is discussed in Section 4.2.1.5.
4-9
-------
4-2.1.2 Freeboard Refrigeration Devices. In all vapor cleaners,
solvent vapor created within the machine is prevented from overflowing
through use of primary condenser coils. Freeboard refrigeration devices
consist of a second set of cooling coils located above the primary
condenser coils of the cleaner. Functionally, the primary condenser coils
define the upper limit of the vapor zone. The freeboard refrigeration
coils chill the air immediately above the vapor zone forming a cool air
blanket. The cool air blanket slows solvent diffusion and creates a
temperature inversion zone within the freeboard which reduces the mixing of
air and solvent vapors. Also, the cool air blanket supports lower solvent
concentrations than warm air. Thus, some solvent at the interface between
the solvent vapor zone and cool air blanket will condense into the cleaner.
Freeboard refrigeration devices have proven to be an effective control for
diffusional losses from an OTVC, although their effect is lessened if a
cool primary condenser is present (see Section 4.2.1.3). A drawing of an
OTVC equipped with a freeboard refrigeration device is presented in
Figure 4-2.
There are two types of freeboard refrigeration devices, above-freezing
and below-freezing. Above-freezing refrigerated freeboard devices operate
at a temperature range around 5°C (41°F). Below-freezing refrigerated
freeboard refrigeration devices operate with refrigerant temperatures
usually in the range of -20 to -30°C (-4°F to -22°F). Due to the low
operating temperatures of the below-freezing units, provisions are made for
a timed defrost cycle to melt the solvent/water ice that may form on the
coils. If allowed to accumulate on the refrigerant coils, this ice layer
would compromise heat transfer efficiency. The solvent/water mixture which
4-10
-------
Condensing Coils
Temperature
Indicator
Cleanout Door
Solvent Level Sight Glass
Freeboard
Condensate Trough
Water
Separator
Heating Elements
Work Rest and Protective Grate
Figure 4-2. Open Top Vapor Cleaner with Freeboard
Refrigeration Device
4-11
-------
is melted from the freeboard coils during the defrost cycle drains to a
trough located below the freeboard refrigerator coils. To minimize water
contamination of the solvent, the melted solvent/water mixture should be
directed to a second water separator (distinct from the separator employed
for the condensate from the primary condensing coils) for removal. Above-
freezing freeboard refrigerated devices condense water from the air. The
condensed water can strip stabilizers that are present in many solvent
mixtures. A cleaner equipped with such a device may also benefit from a
second water separator.
Theoretically, a below-freezing chiller should be more efficient than
an above-freezing chiller since it can achieve lower freeboard
temperatures. Lower freeboard temperatures establish a cooler, more stable
inversion layer which lowers diffusion rates. However, the need to
periodically defrost a below-freezing freeboard refrigeration device can
somewhat offset the performance advantage of below- over above-freezing
chillers.
Twenty-six tests from five sources were available to evaluate the
effect of freeboard refrigeration devices on OTVC's under working (20
tests) and idling (6 tests) conditions. Four tests evaluated above-
freezing chillers (AFC's) while the remainder evaluated below-freezing
chillers (BFC's). All of the tests under idling conditions evaluated
BFC's. Figures 4-3 and 4-4 summarize this data for idling and working
conditions, respectively. Test numbers refer to the tests listed in Tables
4-1 and 4-3.
For working conditions, control efficiencies ranged from 18 to
50 percent for AFC (Tests 1 through 4). Three of the four AFC tests showed
at least a 37 percent emission reduction. Under working conditions
4-12
-------
1-2 1-3 1-4 « 1
Test Numbers (these are idling losses)
\-7
1-8
Figure 4-3. Freeboard Refrigeration Device Tests - Idling Conditions
4-13
-------
0.40
0.10
0.06 -
4 9 10 11 12 13 14 15 16 17 18 19 20
Test Numbers (1 -4 AFC; 9-20 BFC)
Uncontrolled and controlled emission rates vary considerably under the
"working" scenario, much more so than under idling conditions (see Figure 4-3.,
especially notice the low variability in the "controlled" data). This is to be
expected because of the major impact on emissions from the workload. Tests
performed by different companies reflect differing workload sizes, shapes, and
cleaning cycles frequencies. A higher emission rate does not necessarily mean
that a cleaner was less well controlled, but likely reflects the influence of a
more demanding workload schedule or the cleaning of a workload more prone to
carry out losses.
i
Figure 4-4. Freeboard Refrigeration Device Tests - Working Conditions.
4-14
-------
(Tests 9 through 20), control efficiencies for BFC ranged from 28 to
82 percent. The observed 82 percent reduction (Test 12) should be
considered atypical. Freeboard refrigeration devices primarily reduce
diffusional losses. In a working OTVC, losses from solvent carryout on
parts are significant and usually greater than diffusional losses, except
where the machine is in a very drafty location. Therefore, in the more
likely situation where workload related losses are significant or dominate,
it would be impossible to achieve 82 percent emission reduction from a
device designed to control diffusion losses. Controlled working emission
rates for AFC ranged from 0.04 Ib/ft2/hr to 0.12 Ib/ft2/hr. For BFC,
controlled emission rates ranged from 0.01 Ib/ft2/hr to 0.25 Ib/ft2/hr.
Efficiencies for BFC under idling conditions (Tests 1-3 to 1-8) ranged
from 11 to 58 percent. Most notable in this series of tests is that the
primary condensing temperature affects BFC effectiveness for CFC-113. As
primary condensing temperature decreases, the additional benefit of a BFC
also decreases. This effect is not nearly as pronounced with TCA. Primary
condensation temperature is discussed further in the next section.
Controlled idling emission rates with the use of a BFC ranged from
0.04 Ib/ft2/hr to 0.07 Ib/ft2/hr.
The distance between the solvent vapor and secondary refrigerated
freeboard coils has been reported to affect emission rate. An industry
contact stated that this distance should be about 4 to 6 inches,11 because
convection patterns are unfavorable if the distance is outside this range.
A test showed that increasing the separation from 5.5 inches to 7.5 inches
increased losses by 17 percent. Another contact says the distance should
1?
not exceed 8 inches. Still another contact stated that the freeboard
4-15
-------
refrigeration device should be within 4 inches of the top of the solvent
cleaner, regardless of the distance from the primary condenser.13
Available test data are insufficient to determine which distance is most
effective.
Nonetheless, it is important that the freeboard refrigeration device
be able to achieve a significant temperature inversion within the freeboard
area (i.e., a temperature less than room temperature). Poorly designed
freeboard refrigeration devices may not be able to establish the cooler
temperatures at the center of the freeboard zone.
4.2.1.3 Refrigerated Primary Condenser. Although a primary
condenser is standard equipment on all OTVC's, t-ie temperature at which
cooling is provided and the design of the coils and coolant flow have an
effect on idling losses. Heat removal to balance the vapor generating heat
input can be provided at various temperatures, through water, chilled
water, or a direct expansion refrigerant. A lower temperature primary
condenser, generally using a refrigerant as opposed to water, will lower
diffusion losses. The likely reason for this effect is that colder primary
condenser temperatures, besides condensing solvent vapor, also act to cool
the air above the air/solvent vapor interface, somewhat like a freeboard
refrigeration device. This will lower diffusion rates. The magnitude of
this effect varies by solvent.
The relationships between emission rate and primary condenser
temperature under idling and working conditions are presented in
Figure 4-5, for two solvents: TCA and CFC-113 (Table 4-2; Tests 30
through 34). A steeper slope indicates a greater sensitivity to primary
4-16
-------
0.20 -
0.19 -
0.18 -
0.17 -
0.16 -
0.15 -
0.14 -
0.13 -
0.12 -
0.11 -
0.10 -
o.oe -
0.08 -
0,07 -
o.oe -
0.06 -
0.04 -
0.03 -
0.02 -
0.01 -
0 -
TCA (working)
TCA (Idle)
CFC (working)
CFC (kfl«)
30
35
40
T*1
45
50
55
60
65
70
75
T-f-T
80
85
90
Primary Condenser Temperature (F)
Figure 4-5. Effect of Primary Condenser Temperature on Uncontrolled
Idle and Working Conditions
i
4-17
-------
condenser temperature. Uncontrolled working emissions for TCA ranged from
0.17 Ib/ft2/hr at 85°F to 0.10 Ib/ft2/hr at 50°F. Thus, a 41 percent
reduction in working emissions of TCA can be obtained by reducing primary
condenser temperature from 85°F to 50°F. For CFC-113, uncontrolled working
emissions ranged from 0.19 Ib/ft2/hr at 70°F to 0.09 Ib/ft2/hr at 40°F. In
the case of CFC-113, lowering the primary condenser temperature from 70°F
to 40 F yields a 52 percent working emission reduction. It should be noted
that "working" conditions for these test were simulated by introducing a
water-cooled load using a programmable hoist. The load was cycled 12 times
every hour. This type of setup would be expected to simulate relatively
mild working conditions.
Reducing primary condenser temperature during idling has a similar
effect on emissions as for working conditions. Uncontrolled emissions for
TCA range from 0.14 Ib/ft2/hr at 85°F to 0.09 Ib/ft2/hr at 50°F. This
corresponds to an idling loss reduction of 39 percent associated with
decreasing the primary condenser temperature from 85°F to 50°F. For
CFC-113, uncontrolled idling emissions ranged from 0.17 Ib/ft2/hr to
0.06 Ib/ft /hr at 40°F, or a control efficiency of 63 percent under idling
conditions.
It is unlikely that all solvent cleaners using TCA and CFC-113 will
operate their primary condensers at 85°F and 70°F, respectively. In fact,
for CFC-113 machines, primary condensation usually is accomplished through
direct expansion refrigeration or chilled water systems operating at 40 -
60 F. However, even if primary condenser temperatures for TCA and CFC-113
are at 70 F and 50°F, respectively, additional diffusion reduction can
4-18
-------
still be obtained. Referring to Figure 4-5, the tests show that lowering
the primary condenser temperature for TCA from 70°F to 50°F reduces working
2 2
emissions from 0.14 Ib/ft /hr to 0.10 Ib/ft /hr; this corresponds to a 29
percent reduction. Similarly, reducing the primary condenser temperature
on a CFC-113 machine from 50°F to 40°F will reduce working emissions from
0.11 Ib/ft2/nr to 0.09 Ib/ft2/hr, an 18 percent reduction.
These tests also examined the effect of the addition of a
below-freezing freeboard refrigeration device onto a machine operating with
a refrigerated primary condenser. For cleaners using TCA, the addition of
a freeboard refrigeration device to a cleaner with a primary condenser at
50 F still has a significant effect on emissions, reducing emissions by
more than 50 percent. Very little reduction was obtained by adding a
freeboard refrigeration device to a CFC-113 machine operating at a primary
condenser temperature of 40°F.
One drawback to lowering primary condenser temperature is that it
promotes condensation of ambient water vapor, especially in humid climates.
Therefore, it is imperative that machines employing low temperature
condensation contain adequately sized water separators or dessicant dryers
to minimize water contamination.
The test results on primary condenser temperatures suggest another
area of concern for water-cooled OTVC's. Machines using tap water, cooling
tower water, or well water will be subject to seasonal temperature
variations. During summer months condenser water temperatures may rise
significantly and may cause undesirable diffusion loss increases. This
effect may be exacerbated by increased ambient drafts from open doors and
windows in warm weather. Use of chilling or refrigerant systems to control
4-19
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condensing temperatures will minimize seasonal variations.
4-2.1.4 Increased Freeboard Ratio. The freeboard height on an OTVC
is the distance from the the air/solvent vapor interface to the top of the
tank walls. The freeboard zone serves to reduce air/solvent vapor
interface disturbances caused by room drafts and provides a column through
which diffusing solvent molecules must migrate before escaping into the
ambient air. Higher freeboards reduce diffusional losses by diminishing
the effects of air currents and lengthening the diffusion column. An OTVC
with an increased freeboard is presented in Figure 4-6.
In discussing the adequacy of freeboard height to reduce solvent loss,
it is common to refer to the freeboard ratio. The freeboard ratio is the
freeboard height divided by the interior width of the solvent cleaner. The
freeboard height should be measured from the established air/solvent vapor
interface to the top of cleaner walls or to the bottom of any opening in
the cleaner walls. Freeboard width is the inside width of cleaner walls
or, if irregular, the largest width dimension of the air/solvent vapor
interface directly exposed to the atmosphere. The freeboard ratio is used
in recognition of the fact that as cleaner width increases, susceptibility
to the adverse influence of drafts increases unless the freeboard height is
proportionally increased to compensate for the increasing machine width.
Two cleaners of differing size (width) but with identical freeboard ratios
roughly are equally protected from drafts.
A high freeboard on some machines may make it difficult for an
operator to easily lower parts into the machine, unless an elevated work
platform is installed. However, as discussed in Section 4.2.2.1, a hoist
4-20
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Condensing Coils
Temperatur^
Indicator
Cleanout Door
Solvent Level Sight Glass
Heating Elements
Work Rest and Protective Grate
Freeboard
Condensate Trough
Water
Separator
Figure 4-6. Open Top Vapor Cleaner with Increased Freeboard
n
(N
s
4-21
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can be used on large machines to overcome the problem of machine height and
reduce workload related losses. On very large machines, raised freeboards
may be so tall as to restrict the ability to place parts in the machine.
For these situations, slightly lower freeboards might be necessary, but
special care should be taken to minimize room drafts.
For small OTVC sizes, the absolute freeboard height is an important
factor in solvent loss due to diffusion. Despite having a high freeboard
ratio, very small machines may not have sufficient total freeboard height
to prevent accelerated diffusion losses, even in calm environments.
Industry tests show that solvent loss rates can increase substantially with
absolute freeboard heights of less than approximately 12 inches.14 An
example of how emission rates can vary as a function of freeboard height
are presented in Figure 4-7.
Fourteen tests were available to evaluate the effect of an increased
freeboard ratio on solvent emissions. Twelve of the tests evaluated this
effect under working conditions while two tests evaluated idling
conditions. Emission reductions were evaluated for: (a) raising the
freeboard ratio from 0.75 to 1.0, (b) raising the freeboard ratio from 1.0
to 1.25, and (c) raising the freeboard ratio from 0.75 to 1.25. As
mentioned previously, a 0.75 freeboard ratio is representative of baseline
conditions. Although some older machines may have 0.5 freeboard ratio,
most vendors currently sell OTVC with freeboard ratios of at least 0.75.
The available data on the effect of an increased freeboard ratio are
presented in Table 4-1 (Tests 1-19 and 1-20) and Table 4-2 (Tests 47
through 58) for idling and working conditions, respectively. The data for
working conditions are presented graphically in Figure 4-8.
4-22
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0.25
0.20
u
^
c
i
a:
0.15
ro
to
« 0.10
o
co
0.05
0.00
10 IS 20 25
(0-5) (0.75) (1.0) n.25)
Freeboard in inches
(Freeboard Ratio)
Figure 4-7. Solvent loss rate versus freeboard height for Genesolv®
D under Idle conditions
•RegbteredTradamMfc ofABeckSiywl Ccvporvton
30
(15)
-------
0.26
0.24 -
0.22 -
0.20 -
0.18 -
0.16 -
0.14 -
0.12 -
0,10 -
0.06
0.06 -
0.04
0.02 -
0
TESTS 45451
TESTS 46452 + .,
TESTS 47453*...
TESTS 48454 *...„
TESTS 48455 *- ,.'~''"*"•
— ^.'*""**—-—..„.._
TESTS50456 * ~- -K
'"""*
"*"•""—-—>.«4f
0.5
0.7
0.8
FREEBOARD RATIO
-i
1.1
1.3
1.5
Figure 4-8. Effect of Freeboard Ratio - Working Conditions: 6 OTVD Tests
4-24
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Under working conditions, the control efficiencies associated with
raising the freeboard ratio from 0.75 to 1.0 ranged from 19 to 21 percent.
Controlled emission rates at a freeboard ratio of 1.0 ranged from
0.06 Ib/ft2/hr to 0.18 Ib/ft2/hr. The control efficiencies associated with
raising the freeboard ratio from 1.0 to 1.25 ranged from 6 to 10 percent.
The controlled emission rates at a freeboard ratio of 1.25 ranged from
0.06 Ib/ft2/hr to 0.16 lb/ft2 hr. Using the above data, the efficiencies
associated with raising the freeboard ratio from 0.75 to 1.25 are
calculated to be approximately 25 percent.
For idling conditions, data are available to evaluate the effect of
raising the FBR from 0.75 to 1.0. No data are available for estimating the
efficiencies of an increased freeboard ratio to 1.25 under idling
conditions. Under idling conditions, the control efficiencies associated
with raising the freeboard ratio from 0.75 to 1.0 were -6 and 39 percent,
based on two tests. The test with a negative efficiency was conducted
under calm air conditions. Therefore, the expected reduction in emissions
would be lower than for tests conducted under higher air speed conditions.
However, the negative efficiency result can likely be attributed to
measurement inaccuracies. In fact, measured losses for uncontrolled and
controlled scenarios were very small and could be considered the same,
within experimental precision.
Another strategy related to raising the freeboard for emission control
is the design of narrower cleaners. For the same air/solvent vapor
interface area, a square interface configuration is more susceptible to
room drafts than a long narrow rectangular configuration, especially if the
cleaner can be oriented in the room so that any drafts blow across the
narrower dimension.
4-25
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4-2.1.5 Reduced Room Draft/Lin Exhaust Velocities. Air movement over
an OTVC affects the solvent emission rate by sweeping away solvent vapors
diffused into the freeboard area and creating turbulence in the freeboard
area which will enhance solvent diffusion as well as solvent vapor and air
mixing.
In industrial manufacturing settings, solvent cleaners often are
operating in high draft areas, typically in excess of 130 fpm*.15 Reducing
room drafts to calm conditions (30 fpm or less) can greatly reduce emission
rates. The available data for evaluating the effect of reduced room draft
velocity are under working conditions (see Figure 4-9). These data are
from tests showing the effects of draft velocity on emissions at a constant
0.75 freeboard ratio (Table 4-3, Tests 59, 60). .The emission rates from
the tests are 0.23 Ib/ft2/hr at 160 fpm, 0.17 Ib/ft2/hr at 130 fpm, and 0.1
2
Ib/ft /hr at calm conditions. Reducing room drafts to calm conditions
corresponds to a 43 percent reduction from working emissions with room
drafts of 130 fpm and a 58 percent reduction from working emissions at
160 fpm.
A lip exhaust, described in Chapter 3, affects emissions much like air
speed; it increases mixing and diffusion in the vapor layer. Tests have
shown that a lip exhaust, even when properly operated, can double solvent
consumption. If the solvent is not recovered through the use of a carbon
adsorber, overall emissions will increase.
Tests have been conducted on the effect of turning off a lip exhaust
on both idling and working conditions (Table 4-2, Tests 1-16, 1-17, and
1-18 and Table 4-3, Tests 27, 28, and 29, respectively). The lip exhaust
4-26
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0.26
0.24 -
0.22 -
0.20 -
0.18 -
0.16 -
0.14 -
0.12 -
0.10 -
0.06 -
0.06 -
0.04 -
0.02 -
0
• Uncontrolled
20 40 60 60 100 120 140 160 160
Wind Speed (fpm) ('calm'» 30 fpm)
Figure 4-9. Effect of Wind Speed
4-27
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was operated at the rate of 90 ft3/min per ft2 of cleaner area; this
corresponds to 900 ft3/nrin for this particular test. Based on test data
for working conditions, the emission rates encountered with a lip exhaust
system in operation ranged from 0.22 Ib/ft2/hr (with primary condenser
temperature of 50°F) to 0.28 Ib/ft2/hr (with primary condenser temperature
of 85 F). With the lip exhaust turned off, the emission rates decreased
to 0.10 Ib/ft2/hr (at 50°F) and 0.16 Ib/ft2/hr (at 85°F). This corresponds
to a reduction in solvent loss ranging from 54 percent (at 50°F) to
42 percent (at 85°F). The data are presented graphically in Figures 4-10
and 4-11 for idling and working conditions, respectively.
4.2.1.6 Enclosed Design. The enclosed design as a control option for
OTVC's involves completely enclosing the cleaner, except for a single
opening through which parts enter and leave the enclosure. The enclosure
typically precludes manual parts-handling.
Enclosed design OTVC's reduce idling and workload related losses by
creating a still air environment inside the machine which limits solvent
diffusion. Additionally, automated loading and unloading of parts at a
controlled rate creates less air turbulence and reduces solvent carry-out
on cleaned parts.
Schematics of two variations of enclosed designs are shown in
Figure 4-12. The enclosed design with a horizontal entry/exit port
(Figure 4-12.A) is not affected by room air drafts. This design does not
require a port cover during machine operation. The enclosed design with a
4-28
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\//\ Uncontrolled
•i Controlled
M6PC®50F
M 7 PC® TOP
Test Number
M8PC®85F
Figure 4-10. Lip Exhaust Effects - Idling Conditions
4-29
-------
EZ3 UncontroUtd
•I Controlled
27 (PC@30F) 28 (PC®70F)
Test Number (these are working losses)
2fl(PC®8SF)
Figure 4-11. Lip Exhaust Effects - Working Conditions
4-30
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Loading
and
Unloading
Automated
Parts Handling
System
Vapor
Liquid
Sliding
S Cover
Automated
Parts Handling
System
Vapor
Liquid
A. Horizontal Port
B.Vertical Port (with cover)
Figure 4-12. Enclosed Open Top Vapor Cleaners
CO
-------
vertical entry and exit port should have a sliding door that will be closed
except when parts are being loaded or unloaded.
Two data sources were available to evaluate the control efficiency
associated with enclosed design OTVC's.17'18 These sources showed that
uncontrolled OTVC emissions were reduced 42 to 67 percent upon conversion
to an enclosed design machine.
4.2.1.7 Carbon Adsorption. Carbon adsorption can be employed as a
control technique in conjunction with a lip exhaust system. Lip
exhaust/carbon adsorption systems are most commonly used on large solvent
cleaners where the credit from solvent recovery helps to offset the high
capital equipment cost. With these systems, peripheral exhaust ducts
capture the diffusing solvent vapors and to some extent solvent evaporating
from clean parts and directs them through an activated carbon bed. The
solvent vapor molecules are adsorbed onto the activated carbon, removing
the solvent from the vent stream before discharging to the atmosphere.
At intervals, when the carbon becomes saturated with solvent, the bed
is desorbed, usually with steam, to remove the solvent from the carbon.
The solvent/steam mixture is then condensed and passed through a water
separator, and the recovered solvent is returned to the cleaner.
The lip exhaust ventilation system should be designed to maximize
solvent capture efficiency and minimize disturbance of the air/solvent
vapor interface. The percentage of vapor emissions which are captured by
the lip exhaust system is uncertain. Several vendors have indicated a lip
exhaust capture efficiency of 40 to 99 percent but no test data were
provided for justification.19'20'21
4-32
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Proper operation and maintenance procedures are critical to maintain
the control efficiency of carbon adsorption systems. Examples of operating
procedures which have a negative impact on control efficiency include: (1)
dampers which do not open and close properly, allowing solvent-laden air to
by-pass the carbon beds; (2) use of carbon that does not meet
specifications, and (3) improper timing of the desorption cycles.
Desorption cycles must be frequent enough to prevent breakthrough of the
carbon beds, but not so frequent to cause excessive energy consumption.
Carbon adsorbers should not be by-passed during the desorption process. A
dual bed design can be used so that while one bed is being desorbed,
solvent emissions can be routed to the second bed.
One test was available to evaluate the efficiency of carbon adsorbers
22
for controlling solvent emissions. This test indicated that a lip
exhaust/carbon adsorber system could control solvent emissions by
65 percent. However, the test report did not specify whether the baseline
emission rate included lip exhaust. If the baseline OTVC did have a lip
exhaust, the 65 percent emission reduction overstates the achievable
reduction for a carbon adsorber and lip exhaust installed on an OTVC
without a lip exhaust. Thus, there is some uncertainty in the validity of
this data point. Another source indicated that the overall effect of
installing a lip exhaust/carbon adsorber system on an OTVC would be a
23
40 percent reduction in total emissions. Because of the emission
increase associated with adding a lip-exhaust, the overall effectiveness of
control using carbon adsorption for OTVC's is likely closer to 40 percent
than 65 percent.
4-33
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Depending upon the solvent mixture and the type of objects being
cleaned, adverse effects may be encountered with carbon adsorption. Where
solvent mixtures or stabilizers are used, the solvent vapor collected by
the exhaust system may be richer in the more volatile components, and the
recovered solvent mixture will not be identical to the fresh solvent.
Also, some stabilizers or cosolvents used in solvent mixtures are water
soluble. After desorption, the steam used to desorb solvent and
stabilizers from the carbon bed is condensed. The water soluble components
remain in the water and are lost, unless recovered by distillation. Many
users are not willing or able to undertake tasks such as analysis and
reformulation of the solvent, and handling toxic or flammable stabilizers.
In addition, by-products of uncontrolled solvent degradation, such as
hydrochloric acid, can be corrosive to the adsorption equipment and/or
hazardous to operators. For some solvents or cleaning applications, it may
be necessary to use special materials of construction for the adsorber,
such as stainless steel or other alloys, or take other measures to prevent
potential problems which could lead to solvent degradation and damage to
the equipment. One solvent in particular, TCA, is troublesome when used in
carbon adsorption. It is heavily stabilized and many of the stabilizers
may be removed during carbon adsorption, causing solvent breakdown and
equipment corrosion. Carbon adsorption probably should not be attempted
with this solvent at this time. However, recent studies indicate that
carbon adsorption systems for use with TCA will be available in the
future.24
4-34
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4.2.2 Controls for Workload Emissions
4.2.2.1 Mechanically Assisted Parts Handling/Parts Movement Speed.
The method employed for moving parts through the OTVC cleaning cycle has a
direct effect on the magnitude of workload related emissions. Rapid
movement of parts will increase solvent loss due to carry-out of liquid
solvent and entrainment of solvent vapor, and increased disturbance at the
solvent/air interface. As mentioned in Chapter 3, workload losses are a
large portion of total working losses (see Chapter 3 for additional
discussion of workload related losses).
Parts can be moved through the cleaning cycle either by a human
operator or through the use of a mechanical system. A human operator is
generally unable to move parts at or below the maximum speed of 11 feet per
minute (fpm), as required in many State regulations and recommended in EPA
or OC 97
guidelines. ' ' According to one vendor, it is difficult to maintain a
constant speed if a full basket weighs around 10 pounds or more (baskets
28 29
can weigh in excess of 50 pounds). ' Operator training may have limited
success in lowering the basket movement rate. However, the speed of the
basket is difficult to judge, and operators will typically return to faster
rates, especially if the load is heavy enough to cause fatigue toward the
end of the workday. In some industries, operators are paid on a
per-piece basis. This may be further incentive to move parts more
quickly ^1 Industry estimates of parts movement by typical human operators
32 33
are in excess of 60 fpm. ' At these speeds, the working losses would be
much higher, perhaps by several times, than the data presented in Chapter 3
for working losses (reflecting use of hoists). Use of a mechanical parts
4-35
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handling system can reduce emissions by consistently moving parts into and
out of the machine at appropriate rates, thereby eliminating excess losses
caused by manual operation. A parts handling system can be operated by
push button, or can be automatic and programmable. Two typical parts
handling systems are shown in Figure 4-13. The first is a single axis
hoist that can be operated by a push button, whereas the second is a double
axis programmable parts handling system.
Although the emission reduction benefit of using mechanically assisted
parts handling is generally not disputed, there are few data available to
characterize the magnitude of the benefit.
One test is available that simulates the effect of switching from a
human operator to a system (Table 4-3, Test 26)._ The test compared a hoist
operated at 20 fpm (to simulate a human operator) to a hoist operated at
10 fpm. The lower speed was found to reduce working losses by 28 percent.
Since human operator speeds are generally higher than 20 fpm, the reduction
attributable to the use of a hoist is likely larger than 28 percent.
There has been some concern whether even the present 11 fpm limit is
too high. At 11 fpm, substantial disturbance of the air/ solvent vapor
interface still occurs.34'35 Further, lowering the hoist speed can allow
parts to dry more thoroughly prior to removal and create less air
turbulence during part entry and exit from the cleaner. Therefore, working
losses due to solvent carryout and diffusion are minimized. One
manufacturer has evaluated the effectiveness of reducing hoist speed
further, particularly as the parts basket moves through the solvent vapor
layer (Table 4-3, Test 25). During the test, a variable speed,
programmable hoist was used to lower the hoist speed to 3 fpm as the parts
4-36
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Basket
Holder
/
Moving
Mechanical
Arm
CO
Parts
Basket
Control
Panel""
Moving Mechanical Arm
OTVC
Track for
Horizontal
Movement
B. Double Axis Design, Programmable
A. Single Axis Design
Figure 4-13. Automated Parts Handling System
CT
CM
r»
ID
CM
en
ID
-------
basket moved through the solvent vapor. Decreasing the hoist speed from
11 fpm to 3 fpm, resulted in an 81 percent decrease in total working
losses.
Another advantage of mechanical parts handling is the potential for
precise control of dwell time (i.e., the length of time the part remains in
the vapor zone). Proper dwell time decreases emissions by ensuring that
the parts have reached the solvent temperature prior to removal from the
machine. If parts have not reached the solvent vapor temperature,
condensation would still occur as parts are withdrawn from the machine and
solvent carry-out losses would increase. A hoist can also be made to pause
slightly above the air/solvent vapor interface within the freeboard area as
cleaned parts are being withdrawn. This reduces carry-out losses by
allowing pooled solvent to drain or evaporate from the parts with much of
the evaporated solvent either sinking back into the vapor zone or being
condensed on cooling coils. One test measuring the effect of pausing in
the cold air blanket on emission rates indicated that adding a two-minute
dwell above the vapor zone reduced working emissions by 46 percent
(Table 4-3, Test 24). This test was run on parts that collected
substantial amounts of liquid solvent on flat surfaces. Other types of
workloads that do not collect as much liquid on surfaces would not need as
much time to accomplish adequate drying.
An additional benefit of the use of mechanical transport systems is
the ability to reduce worker exposure. In manual operations, a person
operating the cleaner will be near the machine frequently and may have to
bend over the top of the cleaner to lower or extract parts. Mechanical
parts handling not only reduces emissions but also allows the operator to
4-38
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work farther away from the cleaner. This has become especially important
since OSHA has lowered the permissible exposure limit (PEL) for PCE to 25
ppm for an eight-hour period and to 50 ppm for TCE and is expected to lower
the PEL for MC in the near future.
In order to minimize working losses, mechanically assisted parts
handling should be employed while parts are within the solvent vapor,
air/solvent vapor interface, or freeboard area. Parts on which liquid
solvent has pooled or otherwise been trapped should remain in the freeboard
area just above the air/solvent vapor interface until the liquid solvent
has completely evaporated. Also, parts baskets should be suspended from
metal chain or cables, not from fiber rope (or any porous material) which
can absorb solvent.
4.2.2.2 Hot Vapor Recycle/Superheated Vapor. Another means of
dramatically reducing carry out of solvent on cleaned parts is by employing
hot vapor recycle or superheated vapor technology. These two technologies
aim to create zones of superheated solvent vapor within the vapor layer.
Cleaned parts are slowly passed through a superheated zone, warming the
parts and evaporating liquid solvent on parts surfaces before they are
withdrawn from the cleaner. Solvent vapors heated to approximately
1.5 times the solvent boiling point are used. Hot vapor recycle and
superheated vapor technologies are relatively new and predominantly used in
conveyorized cleaners, although development work is continuing on OTVC.
Further discussion of these control techniques and their effectiveness is
contained in Section 4.3.2.3.
4-39
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4-2.3 Proper Operating and Maintenance Practices
Proper operating and maintenance practices are critical to keeping
solvent emissions at a minimal level; neglect can lead to major sources of
emissions. The discussion below recommends practices that will limit
solvent loss due to operating and maintenance activities. No effort was
made to quantify the solvent loss reduction associated with these good
operating and maintenance practices because effectiveness varies widely,
depending on current practices.
Reducing Drafts. Emissions due to diffusion and convection can be
reduced by covering the OTVC when parts are not being cleaned and by
reducing room drafts, such as through the use of baffles or by reducing
room ventilation flow rate near the solvent cleaner.
Sorav Techniques. For OTVC's equipped with spray cleaning systems,
spraying within the vapor zone and at a downward angle helps to control
excess solvent loss. Such a practice reduces liquid solvent forced out of
the OTVC and minimizes turbulence which can increase diffusion losses.
Machines equipped with permanently mounted spray nozzles eliminate the
possibility of spraying outside the vapor zone. With the common use of
ultrasonics to enhance cleaning, the need for solvent sprays on many OTVC
is minimal and could be eliminated.
Allied Corporation tested the effects of spraying location on solvent
loss rates. The data is presented in Table 4-4 for two primary condenser
temperatures. The test data show that it is important to spray parts well
below the vapor line. Solvent losses with spraying 5 inches above the
vapor line are 10 times higher than losses with spraying 4 inches below the
4-40
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vapor line. These tests were conducted using a cleaner with a 24 inch
freeboard and ten 40-second spraying cycles per hour.
Startup/Shutdown Procedures. A proper start-up practice that reduces
solvent emissions involves starting the condenser coolant flow prior to
turning on the sump heater. This practice helps condense solvent from the
saturated zone above the liquid solvent before the air is forced out of the
machine as solvent vapors rise. Conversely, a good shut-down practice
involves allowing the condenser to stay on after the sump heater has been
turned off, until the vapor layer collapses. Solvent cleaners that operate
on a heat pump design cannot accommodate independent control of heating and
cooling, since heat input and condensation are part of the same
thermodynamic cycle.
Downtime Losses. Solvent evaporation during downtime can be
significant, especially so for CFC-113, and methylene chloride. Use of
covers during downtime will reduce drafts and slow diffusion, but will not
stop losses completely. Several techniques can be used to reduce downtime
losses including operating a freeboard refrigeration device, using a sump
cooler to reduce solvent vapor pressure, and pumping solvent out of the
machine to an airtight storage drum. Among these techniques, cooling the
sump during downtime is reportedly very effective at reducing the solvent
losses due to evaporation. Sump cooling can be accomplished by two
methods: 1) the liquid solvent can be cooled during downtime by cooling
coils, or 2) the air blanket directly above the liquid solvent can be
cooled by an overlay coil. One vendor indicated that cooling the sump can
reduce downtime losses by 90 percent.
4-42
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TABLE 4-4. SOLVENT LOSS RATE VERSUS SPRAYING PRACTICES (LB/FT2/HR)
TEN 40 SECOND CYCLES PER HOUR GENESOLV D, 24 INCH FREEBOARD
50° Cooling Water 70° Cooling Water
Loss % Loss %
No Spray 0.0565 0 0.0837 0
4" Below Vapor 0.0742 31 0.1173 40
5" Above Vapor 0.2135 278 0.3010 260
10" Above Vapor 0.5448 864 0.9484 1033
Source: Reference 10
4-41
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Workload Introduction/Removal. Emissions due to the entry and removal
of parts can be reduced with good operating practices. One such practice
is limiting the rate of introduction of the workload in order to minimize
the turbulence created when the load is lowered into the cleaner. Limiting
the rate of introduction of the load so that the air/solvent vapor
interface does not fall more than a few inches will prevent excessive pump
out of mixed solvent vapor and air as the vapor layer reestablishes. As
stated previously, the use of mechanical parts movers can substantially
eliminate these emissions. Emissions can also be reduced by limiting the
horizontal area of the load to be cleaned to 50 percent or less of the OTVC
air/solvent vapor interface area. This will mitigate the displacement and
turbulence of solvent vapors as the load is lowered into the cleaner.
However, larger parts baskets could be used without increasing emissions if
the basket speed were reduced when the basket moved through the vapor zone.
Parts Drainage. An important operating practice that minimizes
solvent carry-out on cleaned parts is proper racking to avoid solvent
puddles if possible. Parts with recesses or blind holes should be rotated
or agitated prior to removal from the vapor layer to displace trapped
solvent. Powered rotating baskets (discussed in 4.3.2.2) can also be used
to limit liquid carry-out effectively. The cleaning of porous or absorbent
materials, which will carry out excessive quantities of solvent, must be
avoided. Also, the part being cleaned should be allowed to reach the
solvent vapor temperature prior to removal from the vapor layer, so that
solvent condensation on the part no longer occurs.
Leak Detection/Repair. Solvent emissions can also be controlled by
repairing visible leaks and repairing or replacing cracked gaskets,
4-43
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malfunctioning pumps, water separators, and steam traps promptly. Routine
equipment inspections will help locate leaks or problem areas more quickly.
Halide detectors that can be used to identify leaks are available at a
reasonable cost ($150 to $500).
Leaks at welded joints can be avoided if the OTVC vendor tests the
joints prior to shipping. The test must be sensitive enough to detect fine
cracks. A simple water test is not sufficient because high surface tension
of water prevents penetration of small cracks. Often a dye penetrant is
used. Machines made with 316L stainless steel walls will be less prone to
stress cracks. Pressure fittings, as opposed to threaded connections, have
also been reported to reduce leaks.38
Clean out doors, viewing ports, or other gasketed machine parts must
be carefully designed and manufactured. Gasket material must be nonporous
and resistant to chemical attack of the solvents used. Ill-fitting gaskets
or use of improper gasketing material can result in large solvent losses.
Solvent Transfer. Losses during transfer of solvent into and out of
the OTVC can be controlled by correct operating practices. Ideally,
solvent filling, draining, and transfer operations should be by pipe in
closed systems. Some vendors have systems that allow for pumping solvent
from the solvent drum directly into the solvent cleaner.39 This could cut
down on spill losses and diffusion associated with solvent filling. If the
solvent is pumped into the cleaner with little or no splashing, such as
with submerged fill piping, less solvent would be lost. Losses during
transfer of contaminated solvent or sump bottoms from the OTVC sump to
stills or waste solvent storage can be controlled by using leakproof
couples. Transfer to a vented tank or sealed containers will help reduce
emissions.
4-44
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Solvent which has been contaminated with water should either be
purified in a water separator or replaced with fresh solvent. Water
contained in the solvent enhances diffusion losses (except for CFC-113
solvent).
Safety Switches. Control switches are devices used on vapor cleaners
to prevent unsafe conditions such as vapor overflow, solvent decomposition,
and excess solvent consumption. Common types of control switches include:
(1) vapor level control thermostat; (2) condenser water pressure switch or
flow switch and thermostat (for water cooled machines); (3) sump
thermostat; (4) liquid solvent level control; (5) spray pump control switch
and (6) secondary heater switch. The first four switches turn off the sump
heat while the fifth turns off the spray when conditions within the machine
exceed proper operating conditions. The most important switch is the vapor
level control thermostat which turns off sump heat when the solvent vapor
zone rises above the design operating level. The secondary heater switch,
found on some machines, is activated when introduction of a large load
causes the vapor level to fall. Secondary heaters reduce solvent loss from
vapor level fluctuation.
As oils, greases, and other contaminants build up in the solvent, the
boiling point of the mixture increases. Both the sump thermostat and
liquid solvent level control prevent the solvent from becoming too hot and
decomposing. The sump thermostat cuts off the heat when the sump
temperature rises significantly above the solvent's boiling point, which
will occur as contamination of solvent increases. The solvent level
control turns off the heat when the liquid level of the boiling sump drops
nearly to the height of the sump heater coils. In the case of electrically
4-45
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and corrosive decomposition products. For steam-heated units, or units
which use a heat pump system, solvent decomposition is less likely because
these heat sources normally do not reach solvent-decomposing temperatures.
However, solvent level controls can be useful on machines using these
heat sources, especially for the higher boiling solvents, trichloroethylene
and perch!oroethylene, because low liquid levels permit high concentration
of soils which can "bake" onto heating elements, seriously impairing heat
transfer and possibly contributing to solvent decomposition. While these
heat sources cannot reach temperatures where solvent decomposition is
rapid, hotter mixtures of solvent and sludges can cause solvent
deterioration more quickly than the cooler operating temperatures of
relatively clean solvent. Therefore, a solvent I.evel switch can still
benefit by signalling the time for solvent cleanup.
The spray pump control switch is not used as often as the other safety
switches, but it can offer a significant benefit. If the vapor level drops
below a specified level, this control cuts off the spray pump until the
normal vapor level is resumed, and then the spray can be manually
re-started. This prevents spraying with an inadequate vapor level, which
can cause excessive emissions of sprayed solvent. The spray pump control
switch sometimes also has a feature which cuts off the spray pump if
spraying is outside the vapor zone.
Although the effectiveness of these controls cannot be quantified, it
is expected that these switches will protect against potentially
significant emissions from upset conditions.
4-46
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4.3 IN-LINE CLEANERS
In-line cleaners can be cold cleaners, vapor cleaners, or a
combination cold/vapor cleaner. However, the majority using chlorinated/
chlorofluorinated solvents are vapor cleaners. These cleaners are nearly
always enclosed except for entrance/exit ports and employ a continuous or
multiple-batch loading systems. Unlike OTVC's which are often
"off-the-shelf" items, they are normally custom-designed for a specific
workload and production rate situation. In-line cleaners are used in a
broad spectrum of metal working industries, but are most often found in
plants where there is a constant stream of parts to be cleaned, and the
advantages of continuous cleaning outweigh the lower capital cost of a
batch loaded OTVC.
The control techniques applicable for use with a in-line cleaner vary
according to the machine design and operation. Presented in this chapter
are the following controls minimizing the entrance/exit openings, carbon
adsorption, freeboard refrigeration devices, drying tunnels, rotating
baskets, and hot vapor recycle/superheated vapor systems.
Test data were not available to evaluate the effectiveness of all the
in-line cleaner control techniques listed above. Only four tests were
available, three that evaluated the effectiveness of a freeboard
refrigeration device (two below-freezing, one above-freezine) and the other
a carbon adsorber. These tests are discussed in the relevant subsections
and are summarized in Table 4-5.
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TABLE 4-5. SUMMARY OF AVAILABLE TESTS - IN-LIME CLEANERS
Tested
Control
AFC
BFC
BFC
CADS
Solvent
GENSOLV DFX
GENSOLV DFX
PCE
TCE
Cleaner
Make
Allied
Allied
Detrex
Blakeslee
Seconday
Chiller
off
off
off
none
Basel ine
Carbon
Adsorber
none
none
none
off
Control l*ri
Emission
(Ib/ft2/hr)
6.2 Ib/hr
6.2 Ib/hr
1.0
1.2
Secondary
Chiller
AFC
BFC
BFC
none
Carbon
Adsorber
none
none
none
on
Emission
(Ib/ft2/hr)
5.7 Ib/hr
1.95 Ib/hr
0.4
0.5
Control
Efficiency
8
69
62
61
AFC = above-freezing freeboard refrigeration device
BFC = below-freezing freeboard refrigeration device
CADS = carbon adsorption system
00
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4.3.1 Controls for Interface Emissions
4.3.1.1 Minimize Entrance/Exit Openings. Although in-line cleaners
are mostly enclosed by design, additional emission control can be achieved
by minimizing opening areas and covering the openings during non-operating
hours. A reduction in the area of entrance and exit openings reduces
idling and working losses due to diffusion by minimizing air drafts inside
the cleaner. Air drafts increase emissions by sweeping away solvent-laden
air near the air/solvent vapor interface and promoting mixing and diffusion
by increasing turbulence in the freeboard area.
Among in-line cleaners, monorail cleaners tend to have the greatest
diffusion emissions due to drafts through the machine caused by openings at
opposite ends. In-line machines utilizing U-bend designs eliminate the
problem of air currents flowing through the machine. Also, many in-line
cleaners, such as monorail cleaners can be constructed so that internal
baffles the effect of air flow through the machine (see Figure 4-14).
Silhouette openings and hanging flaps decrease the area where
diffusion losses can occur and restrict drafts inside the cleaner, but will
have minimal effect on emissions if the openings are already relatively
small. When the in-line cleaner is not in use, port covers should be used
to reduce downtime emissions.
The extent to which reduced entrance/exit opening area affects
emissions is dependent on the total open area. The relative importance of
use of port covers in overall emission reduction depends on the operating
schedule. Port covers are most essential when the fraction of the daily
schedule the cleaner spends in the downtime mode is substantial.
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en
o
Figure 4-14. Baffled Monorail In-line Cleaner
-------
4.3.1.2 Carbon Adsorption. Venting solvent vapor emissions to a
carbon adsorption system is a major emission control technology for both
diffusion losses and workload related losses from in-line vapor cleaners
and cold cleaners. Carbon adsorbers are effective emissions control
devices and can be cost-effective since captured solvent is recycled. The
enclosure around in-line cleaners makes it easier to capture and duct
emissions to the carbon adsorber, and overall efficiencies are higher on
in-lines than OTVC's. The relative degree of emissions control depends on
the cleaner design, workload characteristics, and the solvent emissions
capture efficiency. See Section 4.2.1.7 for more discussion of control by
carbon adsorption.
The available test on carbon adsorbers shows approximately a 60
percent emissions reduction efficiency when applied to an in-line cleaner
(i.e., circuit board stripper).40 Carbon adsorbers are used in both
conveyorized vapor and in-line cold cleaners in many applications.
However, with some solvent mixtures, there could be the same operating
problems described for OTVC's in Section 4.2.1.7.
4.3.1.3 Freeboard Refrigeration Devices. The refrigerated freeboard
device on a in-line vapor cleaner functions in the same way as one on an
OTVC. Refrigeration established a cool air layer above the vapor zone
which inhibits diffusion and solvent-air mixing. (See Section 4.2.1.2 for
a more detailed discussion of freeboard refrigeration devices.)
Only three tests evaluating the effect of freeboard refrigeration
devices on in-line vapor cleaner emissions were available to EPA. One of
these tests evaluated an above-freezing chiller and two evaluated
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below-freezing chillers on an in-line circuit board defluxer. The test
data indicated that a below-freezing chiller can reduce in-line emissions
by about 60 to 70 percent. Above-freezing chillers can achieve about a 10
percent emission reduction.41'42
4.3.2 Control for Workload Emission?
4.3.2.1 Drvino Tunnel?. A drying tunnel is simply an add-on
enclosure which extends the exit area of in-line cleaners. The tunnel
reduces carry-out losses because solvent evaporating from cleaned parts
exiting the machine may be contained within the drying tunnel rather than
being lost to the atmosphere. Much of the evaporated solvent in the drying
tunnel will sink back into the vapor zone, thereby being recovered. Or, if
the machine is connected to a carbon absorber, the evaporated solvent in
the drying tunnel will be drawn into the absorber and recovered. A drying
tunnel works well in conjunction with a carbon adsorber.
The effectiveness of a drying tunnel is dependent on several factors.
Since drying tunnels primarily reduce carry-out emissions, the
effectiveness of this device is dependent on the amount of carry-out before
installation of the tunnel. The amount of control is also dependent on the
length of time that the parts are in the drying tunnel. The length of time
necessary will depend on the solvent type and the parts configuration. If
sufficient time is allowed, essentially all carry-out emissions could be
eliminated (except for the most intricate or "solvent trapping" types of
parts).
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A drawback to the use of a drying tunnel as a control device is the
large amount of floor space that is required. The floor space may not be
available in all plants to add drying tunnels to existing cleaners,
although it can be planned for when new machines are purchased.
4.3.2.2 Rotating Baskets
Rotating baskets may be used to reduce carry-out emissions from
cross-rod cleaners and ferris wheel cleaners or when cleaning parts that
may trap solvent. A rotating basket is a perforated or wire mesh cylinder
containing parts to be cleaned that is slowly rotated while proceeding
through the cleaner. The rotation prevents trapping of liquid solvent on
parts.
As with drying tunnels, the control effectiveness of rotating baskets
is not easily quantifiable. The effectiveness is dependent on the workload
shape and the way the parts are loaded into the basket.
Not all parts are able to be tumbled in baskets without being damaged.
Therefore, rotating baskets are not applicable to all operations. Also,
rotating baskets are designed into the conveyor and hence are not easily
retrofitted on existing cleaners.
4.3.2.3 Hot Vapor Recycle/Superheated Vapor
Hot vapor recycle and superheated vapor are promising, relatively new
technologies. Vendors are reporting that these technologies have the
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potential to significantly reduce carry-out emissions from both OTVC's and
in-line vapor cleaners. An in-line cleaner equipped with superheated vapor
is shown in Figure 4-15.
Both hot vapor recycle and superheated vapor operate on the same
principle. These two technologies aim to create zones of superheated
solvent vapor within the vapor layer. Cleaned parts are slowly passed
through a superheated zone, warming the parts and evaporating liquid
solvent on parts surfaces before they are withdrawn from the cleaner.
Solvent vapor is heated to approximately 1.5 times the solvent boiling
43
point. (One contact indicated that solvent vapor is heated to the
highest temperature possible without decomposing the solvent to speed
drying.44)
The hot vapor recycle process utilizes continuous recirculation of the
solvent vapor. Solvent vapor is drawn from the vapor zone, circulated
through a heater, and blown back into the vapor zone through a system of
distribution slots. In the superheated vapor process, heating coils placed
at one end of the vapor zone superheat a sector of solvent vapor through
which cleaned parts are passed.
Hot vapor recycle is generally applicable only to in-line vapor
cleaners since some type of enclosure is necessary for effective
recirculation of solvent vapor. The movement of vapor creates turbulence
and tends to increase solvent loss unless the machine is enclosed or
baffles are present. Superheated vapor technology can reportedly be
applied to both in-line cleaners or OTVC's. Hot vapor recycle and
superheated vapor have been predominantly used with chlorofluorinated (CFC)
solvents. The technologies are attractive due to potential savings of
4-54
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WorWoad
tn
in
Air/Solvent
Interface
Figure 4-15. Baffled Monorail In-line Cleaner with Superheat Device
-------
costly CFC solvents. Hot vapor recycle has been used in one application to
clean condenser coils in a monorail cleaner using PCE.
No test data have been provided by industry to quantify the control
efficiency possible using hot vapor recycle or superheated vapor
technologies. However, one industry contact claims that a 90 percent
reduction in carry-out emissions is possible.45
The potential for significant emission reduction is apparent.
Normally, cleaned parts will emerge from the vapor zone of a cleaner with a
thin film of liquid solvent on all surfaces, and possibly pooled solvent in
holes and crevices. Much of this liquid solvent may not evaporate until
parts are out of the machine. If all solvent film and pooled solvent is
evaporated prior to leaving the vapor zone, large, solvent savings should
ensue. The only workload related losses remaining would be associated with
air/solvent vapor interface disturbances and vapor entrainment due to the
speed of the conveyor.
4.3.3 Proper Operating and Maintenance Practices
Conveyor Speed. There are several operating and maintenance practices
that can significantly reduce solvent emissions from in-line cleaners. By
controlling conveyor rates at or below 3.3 m/min (11 ft/min) absolute
speed, solvent emissions due to vapor zone turbulence and carry-out can be
minimized. The 11 fpm limit should be measured as an absolute rate, not a
vertical speed (i.e., only 11 feet of conveyor should pass any spot in 1
minute). Conveyor rates can be controlled by the proper gearing of
electric motor drives.
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Sprav Techniques. Emissions can be minimized by proper design of
fixed spray systems. Nozzles should direct spray horizontally or downward
to keep from piercing the vapor layer, or the spray area should be
separated by baffles from the rest of the vapor zone.
Start-up/Shut-down Procedures. Losses can be reduced by the following
methods: (1) starting the condenser water flow prior to turning on the
sump to help condense excess loss as the vapor layer rises; (2) maintaining
the condenser water flow after shut-down of the sump heater until the vapor
layer has collapsed and the liquid solvent has cooled to room temperature;
(3) cooling the sump during downtime or operating cooling coils above the
sump; and (4) covering the entrance and exit ports during downtime.
Carbon Adsorber Procedures. For in-line cleaners with carbon
adsorption systems, several operating practices can be employed which help
to reduce emissions. The practices include (1) not by-passing the carbon
adsorber during the desorption cycle, (2) proper carbon bed regeneration
frequency, so as to prevent solvent breakthrough, (3) leak checks of the
carbon adsorption system,and (4) good steam condensate separations.
Parts Drainage. As with OTVC's, an important operating practice that
minimizes solvent carry-out in in-line operations is proper racking to
avoid solvent puddles. Where pooling of solvent cannot be avoided,
rotating or agitating parts prior to removal from the vapor layer to
displace trapped solvent is necessary. Rotating baskets (discussed in
Section 4.3.5) can also be used to limit liquid carry-out. The cleaning of
porous or absorbent materials, which will absorb and carry out excessive
quantities of solvent, must be avoided. Also, conveyor speed must be
4-57
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adjusted so that parts being cleaned are allowed to reach the solvent vapor
temperature prior to removal from the vapor layer, and solvent is not
visible on emerging parts.
Leak Detection/Repair. Solvent emissions can also be controlled by
repairing visible leaks and repairing or replacing cracked gaskets,
malfunctioning pumps, water separators, and steam traps promptly. Routine
equipment inspections (particularly with a halide detector) will help
locate leaks or problem areas more quickly. Leaks at welded joints can be
avoided if the in-line cleaner vendor tests the joints prior to shipping.
The test must be sensitive enough to detect fine cracks. A simple water
test is not sufficient because high surface tension of water prevents
penetration of small cracks. Often a dye penetrant is used. Machines made
with 316L stainless steel walls will be less prone to stress cracks.
Pressure fittings, as opposed to threaded connections, have also been
reported to reduce leaks.
Clean out doors, viewing ports, or other gasketed machine parts must
be carefully designed and manufactured. Gasket material must be nonporous
and resistant to chemical attack of the solvents used. Ill-fitting gaskets
or use of improper gasketing material can result in large solvent losses.
One test of an in-line cleaner showed that inadequate sealing around a
viewing door accounted for losses of 2.3 Ibs/hour.46 Sealing the window
with duct tape eliminated these losses.
Solvent Transfer. Losses during transfer of solvent into and out of
the in-line cleaner can be controlled by correct operating practices.
Solvent filling and draining should be completed in as closed a system as
possible. As stated previously, some vendors have systems that allow for
4-58
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pumping solvent from the solvent drum directly into the solvent cleaner.
This could cut down on spill losses and diffusion associated with solvent
filling. If the solvent is pumped into the cleaner with little or no
splashing, such as with submerged piping, less solvent would be lost.
Losses during transfer of contaminated solvent or sump bottoms from the
in-line cleaner sump can be controlled by using leakproof couples.
Transfer to a vented tank or sealed containers will help reduce emissions.
Safety Switches. In-line cleaners should also have the appropriate
safety switches to ensure proper operation. A complete discussion of
safety switches is included in Section 4.2.3.
4.4 COLD CLEANERS
As discussed in Chapter 3, carburetor cleaners are the only type of
cold cleaner currently manufactured for use with a halogenated solvent.
These machines are typically well controlled with a water cover. The water
cover substantially limits evaporation losses since very little solvent
comes into contact with the air. Many such machines are designed to be
closed during the cleaning cycle (as well as during downtime and idling)
and further reduce diffusion losses due to drafts and splashing of solvent.
Based on one available test, water covers can reduce evaporation losses by
at least 90 percent. Existing cold cleaners using halogenated solvents
should employ water covers to control evaporation.
Simple work practices can limit working losses. These practices
include allowing adequate drainage of parts and flushing parts only within
the confines of the cleaner.
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4.5 INTEGRATED CONTROL STRATEGIES
This section defines the common elements of well-controlled solvent
cleaning operations and gives specific examples of control technique
combinations that constitute a well-controlled machine. Since solvent
cleaner emissions stem from several sources, a well-controlled and operated
machine will employ a variety of control measures. Purchasers of new
equipment should seek equipment that is designed to provide these elements
of good control. Owners and operators of existing cleaners can
substantially reduce solvent loss by retrofitting the listed controls to an
existing machine.
4-5-l Summary of Solvent Loss Reduction Techniques
The two main elements of a well-controlled solvent cleaning operation
are a good machine design and proper operating practices. A well-designed
machine will have features to limit losses from: (1) diffusion and
convection, (2) carryout, (3) leaks, (4) downtime, (5) solvent transfer,
(6) water contamination, and (7) waste disposal. Proper operating
practices involve minimizing or eliminating leaks, air drafts, spills, and
solvent carryout.
Tables 4-6 through 4-8 summarize the available control techniques
covered in this chapter. All of the good operating practices can be
employed in any solvent cleaning operation. However, all listed control
hardware would not be employed on one machine. There are several devices
to control air/solvent vapor interface losses and workload related losses,
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TABLE 4-6. AVAILABLE CONTROL TECHNIQUES FOR OTVC OPERATIONS
Source of
Solvent Loss
Available Control Hardware
Operating Practices
Air/Solvent
Vapor
Interface
Workload
Fugitive
•
•
t
1.0 FBR (or higher)
Freeboard refrigeration device
Reduced primary condenser temperature
Automated cover
Enclosed design
Carbon adsorber
Reduced air/solvent vapor interface area
Automated parts handling at 11 fpm or less
Carbon adsorber
Hot vapor recycle/superheated vapor
system
Sump cooling system for downtime ,
Downtime cover
Closed piping for solvent and waste
solvent transfers
Leakproof connections; proper materials
of construction for machine parts and gaskets
• Place machine where there are no drafts
• Close cover during idle periods
• Rack parts so that solvent drains
properly
t Conduct spraying at a downward angle
and within the vapor zone
• Keep workload in vapor zone until
condensation ceases
t Allow parts to dry within machine
freeboard area before removal
• Routine leak inspection and
maintenance
t Close cover during downtime
-------
TABLE 4-7. AVAILABLE CONTROL TECHNIQUES FOR IN-LINE OPERATIONS
Solvent Loss
Mechanism
Machine Design
Operating Practices
Air/Solvent
Vapor
Interfaceb
Workload
Fugitive
1.0 freeboard ratio
Freeboard refrigeration device3
Reduced primary condenser temperature3
Carbon adsorber
Minimized openings (clearance between parts
and edge of machine opening is less than
10 cm or 10% of the width of the opening)
t Conveyor speed at 11 fpm or less
• Carbon adsorber
• Hot vapor recycle/superheated vapor
system
•
•
a
Sump cooling system for downtime
Downtime cover or flaps
Closed piping for solvent and waste
solvent transfers
Leakproof connections; proper materials
of construction for machine parts and
gaskets
• Rack parts so that solvent drains
properly
• Conduct spraying at a downward angle
and within the vapor zonea
• Keep workload in vapor zone until
condensation ceases
t Allow parts to dry within machine
before removal
• Routine leak inspection and
maintenance
• Cover ports during downtime
3Applies to in-line vapor cleaners, but not in-line cold cleaners.
bAir/solvent interface for in-line cold cleaners.
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TABLE 4-8. AVAILABLE CONTROL TECHNIQUES FOR COLD CLEANERS
Machine Design
Operating Practices
• Manual cover
0 Water cover with internal baffles
• Drainage facility (internal)
• Close machine during idling and downtime
• Drain cleaned parts for at least
15 seconds before removal
• Conduct spraying only within the confines of
the cleaner
CO
-------
and using them all would be redundant and expensive. The goal of minimum
solvent loss can be met by selecting appropriate combinations of interface
loss controls and workload loss controls. In Section 3.5.2, some workable
combinations are described and evaluated.
4.5.2 Effective Control Technique Combinations
The effectiveness of various control technique combinations at
reducing overall solvent cleaner emissions depends upon the operating
schedule and the specific techniques combined. As noted in Section 3.5,
the overall effectiveness of an individual control technique depends on the
relative contribution of each emission type (idling, workload related,
leaks, downtime, etc.) to total emissions. Those techniques that are
effective at reducing the predominant emission type would be most effective
at reducing overall solvent cleaner emissions. Furthermore, the combined
control efficiency of two or more techniques that act on the same emission
type (e.g., diffusion/convection losses) will be somewhat less than the sum
of the efficiencies for each technique acting alone. Appendix A shows the
derivation of a formula that can be used to calculate the overall
efficiency of control technique combinations. Two or more control
techniques acting on different emission types would have additive control
efficiencies when acting in combination.
Table 4-9 presents estimates of the overall efficiencies associated
with selected control technique options employed on uncontrolled machines
described in Section 3.4. The control options include control technique
combinations and, in the case of in-line cleaners, some single control
technique options. The control technique options shown in
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TABLE 4-9. EFFECTIVENESS OF SELECTED OTVC CONTROL TECHNIQUE COMBINATIONS
Achievable Reduction (%)
Control Technique
Combination Schedule Aa Schedule B
0 Hoist at 11 fpm 40 - 50 50 - 70
Freeboard Refrigeration Device (BF)
1.0 FBR
• Hoist at 11 fpm 70 - 80 70 - 80
Enclosed Design
Sump Cooling
• Hoist at 11 fpm 30 - 40 50 - 60
Automated Cover
t Hoist at 3 fpm 50 - 60 80
Freeboard Refrigeration Device (BF)
1.0 FBR
• Hoist at 3 fpm 80 - 90 90
Enclosed Design
Sump Cooling
• Hoist at 3 fpm 40 - 50 80
Automated Cover
Schedule A assumes the following: 6 hr/day idling; 2 hr/day working; and 16 hr/day downtime for 250 days/yr
and 24 hr/day downtime for 105 day/hr. See Section 3.5 and Appendix B for relative proportion of total
.emissions due to idling, working, and downtime under this schedule.
Schedule B assumes the following: 4 hr/day idling; 12 hr/day working; and 8 hr/day downtime for 250 days/yrs
and 24 hr/day downtime for 105 days/yr.
See Section 3.5 and Appendix B for the relative proportion of total emissions due to idling, working, and
downtime under this schedule.
-------
this table are not meant to be an exhaustive list of the best interactive
controls; other combinations are possible. For example, another in-line
cleaner control option would involve combined hot vapor recycle or
superheated vapor technology with a reduced primary condenser temperature.
However, it is not the scope of this document to evaluate all possible
control options.
Detailed calculations supporting the overall efficiencies of control
technique combinations are contained in Appendices A and B. It should be
noted that the estimated efficiencies assume that operating and maintenance
practices are satisfactory. Improper practices may constitute a major
source of cleaner emissions and may override the reductions achievable with
the listed control techniques. If, for example, a machine has substantial
losses due to leaks or filling, then the emission reductions shown in
Tables 4-9 and 4-10 may not be realized.
4.6 ALTERNATIVE CLEANING AGENTS
Emissions of the five common halogenated solvents used in cleaning
operations can be eliminated through conversion to alternative cleaning
agents. Such cleaning agents include water or aqueous-based detergent,
nonhalogenated solvent (e.g., terpene-based solutions) emulsion
formulations, and new cleaning agents being introduced by solvent producers
that are partially hydrogenated CFC's or blends of partially hydrogenated
CFC's and other nonhalogenated solvents. Many vendors of cleaning
equipment have indicated that there is a significant trend toward
alternative cleaning systems due to concerns about potential health effects
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TABLE 4-10. EFFECTIVENESS OF SELECTED IN-LINE CLEANER CONTROL TECHNIQUE COMBINATIONS
Control Technique
Combination
•
t
t
t
t
•
Freeboard Refrigeration Device
Carbon Adsorption
Carbon Adsorption, Sump Cooling
Freeboard Refrigeration Device
Sump Cooling
Hot Vapor Recycle or Superheated Vapor,
Sump Cooling
Freeboard Refrigeration, Hot Vapor
Recycle or Superheated Vapor
Schedule Aa
50
50
65
65
70
70
Achievable Reduction (%)
Schedule Bb
60
60
60
60
70
85
Schedule A assumes the following: 8 hr/day working; 16 hr/day downtime for 260 days/yr
.and 24 hr/day downtime for 105 days/yr.
Schedule B assumes the following: 16 hr/day working; 8 hr/day downtime for 365 days/yr.
-------
and anticipated regulatory constraints associated with the halogenated
solvents.
Effective alternative cleaning systems are currently being implemented
to replace selected existing halogenated solvent applications. Several
notable alternative systems are listed below:
• At the General Dynamics aircraft facility in Texas, staff
researchers have tested aqueous and emulsion cleaners as
substitutes for several TCE vapor degreasers. Several effective
cleaning agents have been identified and plans are underway to
replace the TCE degreasers.48
• At the US Air Force Aerospace and Meteorology Center in Ohio, a
biodegradable detergent is now used injieu of a CFC system to
clean navigational equipment. At another Air Force base
(Vandenburg), metals parts are now cleaned with an aqueous system
instead of with TCA.49'50
• Rockwell International has evaluated the effectiveness of aqueous
versus solvent ultrasonic cleaning at the Rocky Flats nuclear
weapons facility in Colorado. The aqueous system was found to be
more effective than both TCE and TCA systems.51
t The Torrington Company in Walhalla, South Carolina now uses an
aqueous system to clean metal bearings for the automobile
industry. Previously, vapor cleaners with TCA were used.52
• At AT&T in Massachusetts, a terpene based formulation is being
used to clean printed circuit boards whereas methylene chloride
had been used in the past. Furthermore, General Electric in
Waynesboro, Virginia has converted to an aqueous system to clean
54
printed circuit boards.
4-68
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Despite the potential for increased substitution, there can be several
disadvantages to alternative systems relative to solvent systems. These
include: (1) increased space requirements since alternative systems are
generally larger than comparable solvent systems: (2) potentially higher
energy usages where alternative systems (particularly aqueous) require
substantial energy to heat the cleaning fluid; (3) longer drying times or
need for a separate dryer to remove water from parts being cleaned; and (4)
increased wastewater discharge from disposal of contaminated cleaning
fluid. " Also, if a substitution is made using cleaning agents
containing VOC, the VOC emissions likely will have to be controlled.
There is some indication, however, that these disadvantages can be
overcome. One manufacturer has developed an aqueous cleaner that features
a drastically reduced wastewater problem and high cleaning efficiency.
This type of cleaner relies on thorough agitation of a special cleaning
fluid to keep oils in suspension (and not at the fluid surface) during the
cleaning cycle which avoids recontamination of parts as they are extracted
from the cleaner. Part of the cleaning fluid is continuously pumped to a
separate non-agitated chamber where the oils will separate from the
cleaning fluid and be drawn off by a surface skimmer. The "freshened"
cleaning fluid can then be recycled to the cleaning tank.
Still, there are some cleaning problems for which aqueous or
terpene-based systems may not be suitable, usually because the necessary
degree of cleaning cannot be achieved. Several examples noted by
manufacturers of aqueous and solvent systems include silicon products in
the electronics and medical industries; electronics industry applications
where the circuitry is extremely close to the board (as in newer surface
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mount devices); wax-coated products, and adhesive products.62'63 However,
even more difficult cleaning situations may be handled by newly designed
machines. Alternate cleaning technologies continue to improve.
In summary, alternative cleaning systems can replace existing solvent
vapor cleaning systems in many applications. Compared to solvent systems,
these alternative systems can be economically competitive and can achieve
the same level of cleaning required. The feasibility of substitution,
however, should be evaluated on a case-by-case basis.
The EPA will continue to make available information concerning
alternative cleaning agents as ongoing investigations are completed. The
Global Change Division of the Office of Atmospheric and Indoor Air Programs
has been investigating alternative cleaning systems as part of
stratospheric ozone depletion and global warming mitigation efforts.
Several reports addressing alternative cleaning systems will be available
in the near future.
4-70
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4.7 REFERENCES
1. Letter and attachments from Delta Sonics. February 1988. 6 pages.
Estimation of Freon Solvent Usage in Open Top DS-Series Delta Sonics
Degreasers.
2. Nylen, G. C and H. F. Osterman (Allied Corporation). Cool it to Cut
Degreasing Costs. Am. Mach. November 1982.
3. Suprenant, K. S. and D. W. Richards (Dow Chemical Company). Study to
Support New Source Performance Standards for Solvent Metal Cleaning
Operations. Prepared for the U. S. Environmental Protection Agency.
April 1976.
4. Memorandum from Goodrich, J., Detrex Corporation to Schlossberg,
Detrex Corporation. Degreaser Emissions Control Test Report.
5. Trip report to Autosonics, Norristown, Pennsylvania. Irvin, R.,
GCA/Technology Divison, submitted to L. Jones, U. S. Environmental
Protection Agency. June 14, 1979.
6. Letter from Fiester, D. W., Sealed Power Corporation to EPA central
Docket Section, Washington, D. C. Comments on Organic Solvent Cleaner
NSPS.
7. Reference 1.
8. Letter from Ryan, E. M. to EPA Central Docket Section, Washington,
D.C. Comments on Organic Solvent Cleaner NSPS.
9. Letter and attachments from Polhamus, R. L., Branson Ultrasonics
Corporation, to P. A. Cammer, Halogenated Solvent Industry Alliance.
February 10, 1988. Automated hoist test data.
10. Trip report (amendment) to Allied Corporation, Buffalo Research
Facility. Pandullo, R. F., Radian Corporation. Submitted to
D. A. Beck, U. S. Environmental Protection Agency. January 1989.
11. Reference 10.
12. Letter and attachments from Hoffman, A., Ultra-Kool to D. A. Beck,
U. S. Environmental Protection Agency. December 7, 1987.
13. Letter and attachments from Halbert, J., Delta Sonics, to D. A. Beck,
U. S. Environmental Protection Agency. November, 1987
14. Reference 10.
15. Trip report to Delta Sonics, Paramount, California. Miller, S. J.,
Radian Corporation, submitted to D. A. Beck, U. S. Environmental
Protection Agency. January 1989.
4-71
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4.7 References (Continued)
16. Letter from Barber, J. W., Vic Manufacturing Company, to
Shumaker, J. L., U. S. Environmental Protection Agency. July 8, 1977.
17> Il^TRePort to F1nishin9 Equipment, St. Paul, Minnesota. Rehm, R.,
GCA/Technology Division, to George R., U. S. Environmental Protection
Agency. September 9, 1980.
18. Letter to Tang, J., GCA/Technology Division, from Sabatka, W.,
Finishing Equipment, Inc. May 4, 1981. Solvent and labor savings
from enclosed degreasers.
19. Letter and attachments from Arbesman, P. H., New Jersey Department of
Environmental Protection, to Goodwin, D. R., U. S. Environmental
Protection Agency, August 21, 1978. Capture efficiencies of lip
exhaust systems.
20. Telecon. Miller, S. J., Radian Corporation, with Franz, 0., Phillips
Manufacturing, July 27, 1987.
21. Letter and attachments from Atanley, H., Unique Industries to Farmer,
J. R., U. S. Environmental Protection Agency. April 15, 1987.
Section 114 organic solvent cleaner vendor questionnaire response.
22. Reference 3.
23. Letter from Ward, R. B., duPont to R. Rehm, GCA/Technology Division.
May 3, 1979. Controlling OTVC emissions with carbon adsorption.
24. Letter and attachments from Cemmer, P. A., Halogenated Solvents
Industry Alliance, to Farmer, J. R., U. S. Environmental Protection
Agency. June 7, 1989. Comments at National Air Pollution Control
Techniques Advisory Committee meeting on draft control techniques
document.
25. Letter and attachments from Sherman, James M., Scanex, Inc.
December 29, 1988. 4 pages. Comments on issue of solvent release
from open top solvent cleaning tanks.
26. Trip report to Unique Industries, Sun Valley, California.
Miller, S. J., Radian Corporation, submitted to D. A. Beck, U. S.
Environmental Protection Agency. January 1989.
27. Reference 15.
28. Reference 25.
29. Reference 24.
30. Reference 26.
4-72
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4.7 References (Continued)
31. Telecon. Miller, S. J., Radian Corporation, with M. Mulcahey,
Rhode Island Division of Air and Hazardous Materials. October 5,
1988.
32. Reference 25.
33. Reference 26.
34. Reference 26.
35. Reference 30.
36. Telecon. Miller, S. J., Radian Corporation, with C., Pennington,
Detrex Corporation. November 24, 1987.
37. Reference 15.
38. Summary of Meeting between Corpane and U. S. Environmental Protection
Agency. May 20, 1987.
39. Reference 25.
40. Reference 3.
41. Memorandum from Romig, A.D., Allied Corporation to W.F. LeBail, Allied
Corporation, May 19, 1988. Solvent Reduction Study on CBL Defluxer.
42. Reference 3.
43. Reference 35.
44. Telecon. Miller, S. J., Radian Corporation, with R. Ramsey, duPont,
November 23, 1987.
45. Reference 40.
46. Reference 10.
47. Memorandum from Brown, J.W. and P.R. Westlin, EPA/EMB to D.A. Beck,
EPA/CPB, May 22, 1981. Effect of Water Blanket to Reduce Organic
Evaporation Rates.
48. Evanoff, S.P., K. Singer, and H. Wettman, General Dynamics -
Fort Worth Division. Alternatives to Chlorinated Solvent Degreasing -
Testing, Evaluation, and Process Design. Presented at Industry/EPA
Meeting on Aqueous Cleaning. USEPA/OTS, Washington, D.C.
August 31, 1988.
4-73
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4.7 References (Continued)
49. Patterson, K.B., and D.E. Hunt. U.S. Air Force/Newark Air Force Base
The Cyl-Sonic Cleaner: Aqueous Ultrasonic Cleaning Using
Biodegradable Detergents. Presented at Industry/EPA Meeting on
Aqueous Cleaning. USEPA/OTS, Washington, D.C., August 31, 1988.
50. ICF Consulting Associates and Jacobs Engineering Group, Incorporated.
Guide to Solvent Waste Reduction Alternatives. Prepared for
California Department of Health Services. October 10, 1986.
51. Reference 49.
52. Reference 49.
53. Disposal of Petroferm Terpene Hydrocarbon Wastewater Generated from
Underbrush Cleaning of Circuit Pack Assemblies at AT&T's Merrimack
Valley Works. Presented at Industry/EPA Meeting on Aqueous Cleaning
USEPA/OTS, Washington, D.C., August 31, 1988.
54. Reference 49.
55. Pandullo, R.F., Radian Corporation. Summary of July 1, 1987 Visit to
Finishing Equipment, Incorporated in St. Paul, Minnesota.
56. Pandullo, R.F., Radian Corporation. Summary of September 2, 1987
Visit to Westinghouse Corporation in Orrville, Ohio.
57. Pandullo, R.F. Radian Corporation. Summary of October 18, 1988 Visit
to Delta Industries in Santa Fe Springs, California.
58. Miller, S.J., Radian Corporation. Summary of October 18, 1988 Visit
to Delta Sonics, Incorporated in Paramount, California.
59. Reference 25.
60. Reference 49.
61. Beck, D.A., EPA/OAQPS. Summary of April 7, 1988 Visit to Bowden
Industries, Incorporated in Huntsville, Alabama.
62. Reference 55.
63. Reference 49.
4-74
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5.0 COST ANALYSIS
5.1 INTRODUCTION
This chapter presents costs and cost effectiveness values of various
control options for emissions of methylene chloride (MC), perchloroethylene
(PCE), trichloroethylene (TCE), 1,1,1 trichloroethane (TCA), and trichloro-
trifluoroethane (CFC-113) from organic solvent cleaners. Cost analyses are
provided for controlling emissions from open top vapor cleaners (OTVC's) and
in-line (i.e., conveyorized) cleaners. From available information and as
mentioned in Chapter 4, the only cold cleaner currently manufactured for use
with a halogenated solvent is the carburetor cleaner, which is generally
well-controlled at baseline with a water cover. As a result, no cost analyses
were performed on cold cleaners.
Since organic solvent cleaners comprise a wide range of equipment types,
sizes, and operating techniques, three model cleaner sizes were chosen, and
two operating schedules were composed to evaluate the potential impacts of
controlling solvent emissions. The individual technologies for controlling
halogenated solvent emissions from organic solvent cleaners are presented in
Chapter 4.
Due to the wide variation in solvent cleaner operating schedules, the
most effective control options for a given cleaner may vary. In Chapter 4,
example options for controlling emissions from OTVC's and in-line cleaners
were presented. These options represent a collection of effective control
techniques including controls for reducing losses from idling, working, and
5-1
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downtime. This chapter presents cost analyses for each control option
presented in Chapter 4. Costs were calculated for new cleaners and for
retrofit applications. However, only retrofit costs are presented in this
chapter. Cost tables for new control equipment are included in Appendix C-3.
Section 5.2 presents a description of the overall cost methodology and
assumptions. Sections 5.3 and 5.4 present the information for OTVC's and
in-line cleaners, respectively. These sections present model cleaner
parameters as well as cost effectiveness values. Available capital cost
information on all control techniques presented in Chapter 4 are summarized in
Appendix C-l. Annualized costs are detailed in Appendix C-2. Appendix C-3
includes all tables used in calculating cost effectiveness values for new and
retrofit cases.
5.2 COSTING METHODOLOGY
This section presents a summary of the methodology used to estimate cost
effectiveness of potential control options. The methodology outlined in this
section can be used to determine the cost of other control options using the
information contained in the appendices.
As described in Chapter 4, a complete control program consists of
employing well-designed and manufactured equipment plus operating the
equipment to minimize solvent loss. Aside from the hardware controls costed
here, a number of solvent-saving practices in well controlled solvent cleaners
cannot be readily accounted for in a cost effectiveness calculation. Examples
5-2
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of good operating practices include covering cleaning equipment whenever
possible, properly using solvent sprays, preventing solvent spillage during
solvent transfer, detecting and repairing leaks, proper racking of parts, and
storing waste solvent in closed containers. Quantifying emission reductions
due to these practices is difficult. However, some emission reduction is
certain, unless all good operating practices are already rigorously followed .
The costs are also difficult to quantify, but are expected to be minimal,
primarily slightly more labor time to perform the tasks properly. As a
result, it is anticipated that the cost effectiveness values presented in this
chapter, for hardware controls only, are conservative estimates for situations
where improved operating practices will accrue significant savings.
5.2.1 Model Cleaner Approach
Due to the large number of solvent cleaners and the wide variation in
size of these cleaners, a model solvent cleaner approach was used. Models
were developed to represent typical organic solvent cleaning operations and
types of machines being sold today. The models are not intended to represent
all machines, nor are they intended to represent any specific machine. Two
operating schedules were selected for each model cleaner size to illustrate
the effect operating schedule differences have on control device cost
effectiveness.
The model solvent cleaner sizes used in this memorandum were based on the
sizes reported in vendor responses to a questionnaire sent under
5-3
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Section 114 of the Clean Air Act (CAA) to six of the largest vendors of
solvent cleaners and follow-up with these and other vendors.1"22 Sizes used by
EPA in previous regulatory work under Section 111 of the CAA were also
considered for inclusion. Based on air/solvent vapor interface area, the
following solvent cleaner sizes were chosen:
OTVC's: 4.5ft2, 16ft2
In-line: 38ft2
The in-line cleaner size, 38 ft2, was used to represent both vapor and cold
in-line cleaners. Cold in-line cleaners are photoresist stripping machines
which use only MC. Specific model parameters will be presented in subsequent
portions of this chapter.
5.2.2 Capital Costs
Capital costs include all the costs necessary to design, purchase, and
install a particular control device or new equipment addition. A summary of
capital costs used in this chapter is presented in Table 5-1. All available
cost information for these and other control devices (described in Chapter 4)
is included in Appendix C-l.
The basis for estimating control costs was primarily information
contained in Section 114 questionnaire responses discussed above. Additional
information was obtained through telephone contacts with several other
23-31
vendors. The Section 114 responses included information on model solvent
cleaner sizes, control equipment costs, and operating requirements for control
equipment. The costs for the model solvent cleaners were estimated from the
5-4
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TABLE 5-1. CAPITAL COSTS (1988) USED IN COST ANALYSIS
Total Installed Capital Costs
New Retrofit
Open TOD Vapor Cleaners
Small OTVC 4.5 ft
2
Automated Parts Handling
Below-freezing FRD
Bi-Parting Cover
1.0 Freeboard Ratio
Enclosed Design
Sump Cool ing
1,500 - 2,000 1,500 - 2,000
4,500
7,900
500
3,000
1,500
5,400
8,500
500
3,000
1,500
Large OTVC 16.0 ft'
Automated Parts Handling
Below-freezing FRD
Bi-Parting Cover
1.0 Freeboard Ratio
Enclosed Design
Sump Cooling
3,000 - 3,500 3,000 - 3,500
8,600
10,200
600
10,000
1,500
10,300
11,300
600
10,000
1,500
In-Line Cleaners 38.0 ft
Below-freezing FRD
Carbon Adsorber
Super Heated Vapor
14,700
61,000
3,000
17,700
74,900
3,000
FRD - Freeboard refrigeration device
5-5
-------
range of costs for cleaners of similar size to the model solvent cleaner
sizes. Costs were also developed for two additional OTVC sizes (8.6 ft2 and
2
38 ft ). These costs are included in Appendix C-l.
Total installed capital costs reported in the vendor responses were for
retrofit and new control equipment. Since these costs were reported as
installed, they include sales taxes, freight, and installation charges.
Average costs based on all vendor quotes for each model solvent cleaner and
each control option were calculated. These average values were then adjusted
using engineering judgement and the following considerations:
• The costs received from different vendors often varied for identical
controls. In order for model solvent cleaner costs to best
represent the industry, costs from larger vendors were weighted more
heavily than the smaller vendor costs.
• Most manufacturers submitted costs for some, but not all, model
solvent cleaner sizes. Also, as indicated above, the reported costs
often varied significantly for identical controls. Consequently,
there was the possibility that taking straight averages of cost of
certain controls would not make sense. For example, using this
approach, the costs associated with controls for larger size
cleaners were sometimes less than for smaller cleaners, and retrofit
costs were sometimes less than new costs. Costs were adjusted to
eliminate these discrepancies.
5-6
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• Some manufacturers responding to the questionnaire do not
manufacture all the controls for which they provided costs. Their
costs, therefore, included purchasing the control from another
vendor plus a markup. Costs from these manufacturers were used only
when they actually retrofitted a significant number of the control
devices (as reported in the vendor questionnaires and in follow-up
contacts). Estimates of operating costs were also adjusted to
reflect the values obtained from vendors actually supplying the
controls.
A detailed discussion of the derivation of specific capital costs for each
model cleaner is included in Appendix C-l. A description of the items costed
for each control technique is listed below:
• automated parts handling: The costs for an automated parts handling
system includes a range. The lower cost in each size range is for a
push-button hoist capable of moving at a constant 11 fpm. The
higher cost is for a push-button hoist capable of moving at 11 fpm,
except when moving through the air/solvent vapor interface and
freeboard area, when it moves at 3 fpm. The system for the small
OTVC has a 30 Ib capacity and for the large OTVC has a 100 to 200
Ib. capacity.
• below-freezing freeboard refrigeration device: The costs for this
control technique are based on the costs for units approximately the
5-7
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size of each of the model units listed above. The costs include the
coiled tubing that are lowered into the solvent cleaner as well as
the required compressor for the refrigerant. [The above-freezing
freeboard refrigeration devices included 1n Appendix C-l are assumed
to be water cooled.]
• bi-parting cover: The costs for a bi-parting cover are based on a
wide range of vendor quotes as described in Appendix C-l. The costs
presented include estimated costs for the bi-parting mylar cover as
well as the motors to run the covers.
• 1.0 freeboard ratio: The costs for an increased freeboard ratio
include only the cost of a stainless steel extension to the
freeboard. Any engineering costs would be incurred only once for
each model and were, therefore, not included in costs for individual
owners and operators.
• enclosed design: The costs for an enclosed design includes the cost
to add an enclosure to the top of an open-top vapor cleaner. The
enclosure, depicted in Figure 4-b, has a vertical opening. The
costs do not include the costs of an automated parts handling
system that would be necessary with an enclosed design.
t sump cool ing: The costs for sump cooling include the cost of a coil
located directly above the solvent sump, as well as the necessary
compressor.
5-8
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• carbon adsorber: The costs for a carbon adsorption system include
two activated carbon beds, a blower, and a condenser.
• super-heated vapor: The costs for a super-heated vapor include the
cost for heating coils and extenstion to the cleaner at the exit
area.
Since all costs are based on a range of vendor quotes, actual costs
experienced by individual machine operators will vary. However, the costs
presented are considered to be representative of average costs nationwide.
Capital costs were annualized based on an annual percentage rate of
10 percent and the following equipment lifetimes bajed on vendor
questionnaires:
OTVC: 10 years32'33'34
In-line: 15 years35'36'37
All controls except carbon adsorbers were assumed to have the same lifetime as
the solvent cleaner. A carbon adsorber has a reported lifetime of 10 years
38
and was annualized over this life span.
5.2.3 Annual Operating Costs
Annual operating costs associated with solvent cleaner emission controls
include such items as annualized capital charges, added labor, electricity,
cooling water and steam, floor space, and other miscellaneous costs incurred
due to use of each control. A summary of the operating cost parameters are
5-9
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included in Table 5-2. Operating cost derivations are detailed in
Appendix C-2. Steam costs are calculated for the steam necessary to desorb
carbon adsorber beds. Additional cooling water is also required for carbon
adsorption systems to condense the solvent-laden steam after desorption. The
additional floor space required for each control device is also costed where
appropriate. Additional floor space requirements were based on manufacturers
specifications.
In addition to calculating the increased annual operating costs, a credit
is calculated for the reduction in solvent emissions credited to the control
device. A reduction in emissions translates into a corresponding reduction in
solvent consumption, thus saving the operator solvent expense. The credit is
calculated using the solvent costs presented in Table 5-2.
5.3 OPEN TOP VAPOR CLEANERS
5.3.1 Model Cleaner Parameters
Open top vapor cleaners typically range in size from approximately 4 ft2
to greater than 50 ft , though the majority of cleaners are less than 20 ft2.
The model cleaners used in this chapter to analyze control costs were selected
to be representative of this range. The two model sizes are 4.5 ft2 and
2
16 ft . The model cleaner parameters for OTVC's are presented in Table 5-3.
The parameters are based on industry contacts and EPA studies of the solvent
cleaning industry.
5-10
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TABLE 5-2. SUMMARY OF OPERATING COST PARAMETERS
Original Quoted
Cost
Year
1988
Cost
Reference
Material
Methylene Chloride
Perchloroethylene
Tri chloroethylene
1,1,1 Trichloroethane
Tri chlorotri f1uoroethane
$0.259/1b
$0.31/lb
$0.385/1b
$0.405/1b
$0.90/lb
39
40
41
42
43
Utility
Electricity
Steam
Cooling Water
$.0713/kWh 1986
$5.65/1000 Ib 1984
$0.08/1000 gal 1980
$.0780/kWh 44
$5.98/1000 Ib 45
$0.099/1000 gal 46
Labor
Operating Labor
Maintenance Labor
$7.87/manhour 1977
$8.66/manhour 1977
$13.78/manhour 47
$15.16/manhour 47
Miscellaneous
Additional Space
42/ft'
1980
55.7/ft'
48
Utilities and labor rates (operating and maintenance) were increased using
Bureau ofQLabor Statistics (BLS) producer price indices. These are as
follows:
4th quarter
1977
1980
1984
1986
1988
62.5
88.0
103.3
100.0
109.4
Building space costs were increased from 1980 to 1986 dollars using CE plant
cost indices for building. These are as follows:
November 1980 (final) - 244.7
November 1986 (final) - 304.4
November 1986 (prelim) - 324.4
50
51
52
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As shown in Table 5-3, two operating schedules were evaluated for each
model cleaner size. These schedules were selected to represent the wide range
of operating schedules that exist in solvent cleaning operations and were
detailed in Chapter 3.
Based on correspondence with industry concerning characteristics of
cleaners manufactured over the last several years, an OTVC has a freeboard
ratio of 0.75, a manual cover used in downtime, a primary condenser
temperature of approximately 75°F, and the appropriate safety
40 41 42
switches. ' ' As discussed in Section 3.4, uncontrolled emissions were
calculated for losses due to idling, working, and downtime emission rates.
Uncontrolled emissions from OTVC's were estimated to be 2,890 Ib/year and
6,940 Ib/year for the small OTVC under schedules A and B, respectively.
Uncontrolled emissions from the large OTVC were estimated at 10,300 Ib/year
and 24,700 Ib/year for operating schedules A and B, respectively.
No emission reduction credit or control cost has been included for use of
the cover during downtime and idle time or for the operation of safety
switches since these are assumed to be common practice at baseline. The
following six control options were considered as control alternatives:
t Control Option 1: an automated parts handling system operating at
11 fpm, a below-freezing freeboard refrigeration
device, and a 1.0 freeboard ratio;
t Control Option 2: an automated parts handling system operating at
11 fpm, an enclosed design, and sump cooling
during downtime;
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• Control Option 3: an automated parts handling system operating at
11 fpm, and a bi-parting cover capable of being
closed during operation;
Control Option 4:
an automated parts handling system operating at
3 fpm (when parts are entering/leaving the vapor
zone), a below-freezing freeboard refrigeration
device, and a 1.0 F6R;
Control Option 5: an automated parts handling system operating at
3 fpm (when parts are entering/leaving the vapor
zone), an enclosed design, and sump cooling; and
Control Option 6:
an automated parts handling system operating at
3 fpm (when parts are entering/leaving the vapor
zone), and a bi-parting cover capable of being
closed during operations;
Based on the existing test data, ranges of efficiencies for each
individual control device were estimated. The overall control efficiency was
calculated by summing individual control efficiencies for each device in an
option, weighted according to the amount of time per year that the emissions
of each type (idling, working, downtime) occurred. The overall efficiency
differs for different operating schedules. A more complete discussion of
control efficiency derivations is included in Appendix B.
5-13
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The ranges of efficiencies for each control option for each operating
schedule are summarized at the bottom of Table 5-3. It should be noted that
all reported efficiencies include only the control of the three primary
emission types. They do not account for leaks, wastewater losses, or transfer
losses which should be minimal if proper practices are employed. However, if
another emission type is not controlled (such as an undetected leak) and
becomes a major source, then the efficiencies reported in Table 5-3 are
overstated. In general, Control Option 5 had the highest overall control
efficiency, ranging up to 90 percent control. Control Option 2 was generally
the next most effective, except for the large OTVC under Schedule B where
Control Option 6 has the second highest efficiency. Control Options 1 and 3
generally have the lowest overall efficiencies.
5.3.2 Model OTVC Cost Evaluation
Table 5-4 shows the capital costs, annualized operating costs, emission
reduction, solvent recovery credit, net annualized control costs, and cost
effectiveness of each of these options for a model OTVC using MC. Tables 5-5
through 5-8 summarize this information for PCE, TCE, TCA, and CFC-113,
respectively. The tables detailing these costs (and presenting the values for
new OTVC's) are presented in Appendix C-3.
Generally, the ranking of the cost effectiveness values was independent
of solvent type. The only variable among the calculations for each solvent
was the solvent price (listed in Table 5-2). Therefore, the higher priced
solvents generate higher solvent recovery credits and, therefore, lower net
5-14
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TABLE 5-3. MODEL CLEANER PARAMETERS FOR OPEN TOP VAPOR CLEANERS
Parameter Small - Schedule A
Working area, ft 4.5
Solvent All
Operating schedule hr/year
Idling 1560
Working 520
Downtime 6656
Uncontrolled emission rates Ib/hr
Idling 0.675
Working 1.800
Downtime 0.135
Uncontrolled emissions8 (Ib/yr)
Idling 1050
Working 940
, Downtime 900
•— Total 2890
in
Control Option . 123456
Controlled emissions (Ib/yr) 1730-1440 870-580 2020-1730 1440-1160 580-290 1730-1440
Total
Emission Reduction 1160-1440 2020-2310 870-1160 1440-1730 2310-2600 1160-1440
Uncontrolled emissions based on 0.75 FBR, cover in downtime. Efficiency Range (X)
Controlled emissions based on the following:
Control Option 1: Automated Parts Handling System a 11 fpm; Below-freezing FRO; 1.0 FBR 40 - 50
Control Option 2: Automated Parts Handling System a 11 fpm; Enclosed Design; Sump Cooling 70 - 80
Control Option 3: Automated Parts Handling System a 11 fpm; Automated Bi-parting Cover 30 - 40
Control Option 4: Automated Parts Handling System a 3 fpm; Below-freezing FRO; 1.0 FBR 50 - 60
Control Option 5: Automated Parts Handling System a 3 fpm; Enclosed Design; Sump Cooling 80 - 90
Control Option 6: Automated Parts Handling System a 3 fpm; Automated Bi-parting Cover 40 - 50
cRange based on range of Control Efficiencies
FRO - Freeboard refrigeration devices
FBR - Freeboard ratio
NOTE: All reported efficiencies are for control of idling, working, and downtime losses only. They do not account for leaks,
uastewater losses, or transfer losses which should be minimal if proper practices are employed.
-------
TABLE 5-3. MODEL CLEANER PARAMETERS FOR OPEN TOP VAPOR CLEANERS (Continued)
Parameter
Working area, ft2
Solvent
Operating schedule hr/year
Idling
Working
Downtime
Uncontrolled emission rates Ib/hr
Idl ing
Working
Downtime
Uncontrolled emissions0 (Ib/yr)
Idl ing
Working
Downtime
Total
Control Option . 1
Controlled emissions (Ib/yr) 3470-2080
Total0
Emission Reduction 3 A 70 -4860
Uncontrolled emissions based on 0.75 FBR, cover
b
Controlled emissions based on the following:
Control Option 1: Automated Parts Handling
Control Option 2: Automated Parts Handling
Control Option 3: Automated Parts Handling
Control Option 4: Automated Parts Handling
Control Option 5: Automated Parts Handling
Control Option 6: Automated Parts Handling
cRange based on range of Control Efficiencies
FRO - Freeboard refrigeration devices
FBR - Freeboard ratio
NOTE: Alt reported efficiencies are for control
Small - Schedule B
4.5
All
1560
520
6656
0.675
1.800
0.135
700
5620
620
6940
23456
2080-1390 3470-2770 1390 690 1390
4860-5550 3470-4160 5550 5240 5550
in downtime. Efficiency Range (X)
System a 11 fpm; Below-freezing FRO; 1.0 FBR 50 - 70
System a 11 fpm; Enclosed Design; Sump Cooling 70 - 80
System a 11 fpm; Automated Bi -parting Cover 50 - 60
System a 3 fpm; Below-freezing FRD; 1.0 FBR 80
System a 3 fpm; Enclosed Design; Sump Cooling 90
System a 3 fpm; Automated Bi -parting Cover 80
of idling, working, and downtime losses only. They do not account for leaks.
wastewater losses, or transfer losses which should be minimal if proper practices are employed.
-------
TABLE 5-3. MODEL CLEANER PARAMETERS FOR OPEN TOP VAPOR CLEANERS (Continued)
tn
Parameter
Working area, ft
Solvent
Operating schedule hr/year
Idl ing
Working
Downtime
Uncontrolled emission rates Ib/hr
I d I i ng
Working
Downtime
Uncontrolled emissions (Ib/yr)
Idl ing
Working
Downtime
Total
Control Option .
Controlled emissions (Ib/yr)
Totalc
Emission Reduction
1
6160-5130
4110-5130
Uncontrolled emissions based on 0.75 FBR, cover
Controlled emissions based on the following:
Control Option 1: Automated Parts Handling
Control Option 2: Automated Parts Handling
Control Option 3: Automated Parts Handling
Control Option 4: Automated Parts Handling
Control Option 5: Automated Parts Handling
Control Option 6: Automated Parts Handling
Large - Schedule A
16.0
All
1560
520
6656
2.40
6.40
0.48
3740
3330
3200
10270
23456
3080-2050 7190-6160 5730-4110 2050-1030 6160-5130
7190-8210 3080-4110 5130-6160 8210-9240 4110-5130
in downtime. Efficiency Range (X)
System a 11 fpm; Below-freezing FRO; 1.0 FBR 40 - 50
System a 11 fpm; Enclosed Design; Sump Cooling 70 - 80
System ail fpm; Automated Bi -part ing Cover 30 - 40
System a 3 fpm; Below- freezing FRD; 1.0 FBR 50 - 60
System a 3 fpm; Enclosed Design; Sump Cooling 80 - 90
System a 3 fpm; Automated Bi -parting Cover 40 - 50
Range based on range of Control Efficiencies
FRD - Freeboard refrigeration devices
FBR - Freeboard ratio
NOTE: All reported efficiencies are for control of idling, working, and downtime losses only.
wastewater losses, or transfer losses which should be minimal if proper practices are employed.
They do not account for leaks.
-------
TABLE 5-3. MODEL CLEANER PARAMETERS FOR OPEN TOP VAPOR CLEANERS (Continued)
00
Parameter
Working area, ft
Solvent
Operating schedule hr/year
Idl ing
Working
Downtime
Uncontrolled emission rates Ib/hr
Idling
Working
Downtime
Uncontrolled emissions8 (Ib/yr)
Idling
Working
Downtime
Total
Control Strategy . 1 2
Controlled emissions (Ib/yr) 12300-7400 7400-4930
Total
Emission Reduction 12300-17300 17300-19700
"uncontrolled emissions based on 0.75 FBR, cover in downtime.
u
Controlled emissions based on the following:
Control Strategy 1: Automated Parts Handling System a 11 fpm;
Control Strategy 2: Automated Parts Handling System a 11 fpm;
Control Strategy 3: Automated Parts Handling System a 11 fpm;
Control Strategy 4: Automated Parts Handling System a 3 fpm;
Control Strategy 5: Automated Parts Handling System 9 3 fpm;
Control Strategy 6: Automated Parts Handling System a 3 fpm;
cRange based on range of Control Efficiencies
FRD - Freeboard refrigeration devices
FBR - Freeboard ratio
NOTE: All reported efficiencies are for control of idling, working
Large - Schedule B
16.0
All
1560
520
6656
2.40
6.40
0.48
2500
19970
2200
24670
3456
12300-9860 4930 2470 4930
12300-14800 19700 22200 19700
Efficiency Range (X)
Below-freezing FRD; 1.0 FBR 50 - 70
Enclosed Design; Sump Cooling 70 - 80
Automated Bi-parting Cover 50 - 60
Below-freezing FRD; 1.0 FBR 80
Enclosed Design; Sump Cooling 90
Automated Bi-parting Cover 80
, and downtime losses only. They do not account for leaks,
wastewater losses, or transfer losses which should be minimal if proper practices are employed.
-------
Table 5-4. SUMMARY OF RETROFIT CONTROL COSTS AND COST EFFECTIVENESS FOR MODEL OTVC's USING METHYLENE CHLORIDE (1988 S)
in
1.
2.
3.
4.
5.
6.
Control Option
Automated Parts Handling System 311 fpm;
Below- freezing FRO; 1.0 FBR
Automated Parts Handling System 311 fpm;
Enclosed Design; Sump Cooling
Automated Parts Handling System 311 fpm;
Automated Bi -part ing Cover
Automated Parts Handling System a 3 fpm
Below-freezing FRO; 1.0 FBR
Automated Parts Handling System a 3 fpm;
Enclosed Design; Sump Cooling
Automated Parts Handling System a 3 fpm;
Automated Bi -part ing Cover
Cleaner Total Total
Size/ Installed Annualized Emission
Operating Capital Cost Cost Reduction
Schedule ($) ($/yr) (Ib/yr)
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
8,180
8,180
15,200
15,200
6,220
6,220
14,700
1,470
10,200
10,220
14,500
14,500
8,680
8,680
15,700
15,700
6,720
6,720
15,200
15,200
10,700
10,700
15,000
15,000
2,200
2,770
3,630
4,200
1.820
1,790
3,740
3,640
2,090
2,200
2,980
3,160
2,300
2,880
3,740
4,310
1,920
1,890
3,8^0
3,750
2,200
2,300
3,080
3,260
1,160- 1,440
3,470- 4,860
4.110- 5,130
12,300-17.300
2,020- 2,310
4,860- 5,550
7,190- 8,210
17,300-19,700
870- 1,160
3,470- 4,160
3,080- 4,110
12,300-14,800
1.440- 1.730
5.550
5.130- 6.160
19,700
2,310- 2,600
6,240
8,210- 9,240
22,200
1,160- 1.440
5,550
4,110- 5,130
19,700
Recovered
Solvent
Credit
<*/yr>
(1.040)-(1.300)
(900)-(1.260)
(1,060)-(1,330)
<3,190)-(4,470)
(520)-(600)
(1.260)-(1.440)
(1.860)-(2,130)
(4.470)-(5,110)
(220)-(300)
(900)-(1,080)
(800)-(1.060)
(3,190)-(3.830)
(370)-(450)
(1.440)
(1,330)-(1,600)
(5,110)
(600)-(670)
(1.620)
(2,130)-(2,390)
(5.750)
(300)-(370)
(1.440)
(1,060)-(1.330)
(5.110)
Net
Annualized
Cost
($/yr)
1,170-900
1,880-1,520
2,570-2,300
(1,010)-(270)
1,300-1,220
530-350
1.880-1,610
(830)-(1460)
1,870-1,790
1.300-1,120
2,180-1,920
(30)-(670)
1.930-1,860
1440
2,410-2,140
(800)
1.320-1,250
270
1,710-1,440
2,000
1,900-1,820
860
2,020-1,750
1,850
Cost
Effectiveness
($/lb)
1.0 - 0.6
0.5 - 0.3
0.6 - 0.4
0.1 -(0.02)
0.6 - 0.5
0.1 - 0.06
0.9 - 0.3
0.2 -(0.05)
2.2 - 1.6
0.4 - 0.3
0.7 - 0.5
0 -(0.1)
1.3 - 1.1
0.3
0.5 - 0.4
(0.04)
0.6 - 0.5
0.04
0.2 - 0.2
0.1
1.6 - 1.3
0.2
0.5 - 0.3
0.1
FRD = freeboard refrigeration device
OPERATING SCHEDULES:
Schedule A: 6 hours idling; 2 hours working; 16 hours downtime; 5 days/week; 52 weeks/year
Schedule B: 4 hours idling; 12 hours working; 8 hours downtime; 5 days/week; 52 weeks/year
-------
Table 5-5. SUMMARY OF RETROFIT CONTROL COSTS AND COST EFFECTIVENESS FOR MODEL OTVC's
USING PERCHLOROETHYLENE (1988 S)
1.
Automated
Control
Parts Handl
Below-freezing FRO; 1
2.
Automated
Parts Handl
Enclosed Design; Sump
3.
4.
Automated
Automated
Automated
Parts Handt
Bi-parting
Parts Handl
Below- freezing FRD; 1
5.
Automated
Parts Handl
Enclosed Design; Sump
6.
Automated
Automated
Parts Handl
Bi-parting
Option
ing System 311 fpm;
.0 FBR
ing System 311 fpm;
Cool ing
ing System 311 fpm;
Cover
ing System 3 3 fpm
.0 FBR
ing System 3 3 fpm;
Cooling
ing System 3 3 fpm;
Cover
Cleaner Total
Size/ Installed
Operating Capital Cost
Schedule ($)
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
8,180
8,180
15,200
15,200
6,220
6,220
14,700
1,470
10,200
10,220
14,500
14,500
8,680
8,680
15,700
15,700
6.720
6,720
15,200
15.200
10,700
10,700
15,000
15,000
Total
Annual) zed Emission
Cost Reduction
(*/yr) (Ib/yr)
2,200
2,770
3,630
4,200
1,820
1,790
3,740
3.640
2,090
2,200
2,980
3,160
2,300
2,880
3,740
4,310
1,920
1,890
3.840
3.750
2.200
2,300
3,080
3,260
1,160- 1,440
3,470- 4,860
4,110- 5,130
12,300-17,300
2,020- 2,310
4,860- 5,550
7,190- 8,210
17,300-19,700
870- 1,160
3,470- 4.160
3,080- 4,110
12,300-14,800
1,440- 1.730
5.550
5,130- 6,160
19,700
2,310- 2,600
6.240
8,210- 9,240
22,200
1,160- 1,440
5,550
4,110- 5,130
19,700
Recovered
Solvent
Credit
<*/yr)
(360)-<450)
(1,080)-(1,500)
(1.270)-<1.590)
(3,820)-(5,350)
(630)-(720)
(1,500)-(1,720)
(2,230)-(2,550)
(5.350)-(6.120)
(270)-(360)
(1,080)-(1.290)
<960)-(1.270)
(3.820)-(4.590)
(450)-(540)
(1720)
(1.590)-(1,910)
(6.120)
(720)-(810)
(1,940)
(2,550)-(2,860)
(6,880)
(360)-(450)
(1.720)
(1,270)-(1,590)
(6,120)
Net
Annual i zed
Cost
(S/yr)
1,850- 1.760
1,700- 1,270
2,360- 2,040
380-(1,150)
1,190- 1,100
280- 70
1,510- 1,190
(1,710)-(2.470)
1,820- 1,740
1,120- 910
2,020- 1.710
(660)-(1.420)
1,860- 1,770
1,160
2,140- 1,830
(1,810)
1,200- 1,120
50
1,290- 970
(3,130)
1,840-1,750
581
1,810-1,490
(2,850)
Cost
Effectiveness
(S/lb)
1.6
0.5
0.6
- 1.2
- 0.3
- 0.4
0.03 -(0.1)
0.6
0.06
0.2
- 0.5
- 0.01
- 0.1
(0.05)-(0.07)
2.2
0.3
0.7
(0.05)
1.3
0
0.4
(0.
0.6
0.
0.2
(0
1.6
0
0.4
(0
- 1.6
- 0.2
- 0.4
-(0.1)
- 1.1
.2
- 0.3
04)
- 0.5
01
- 0.1
.1)
- 1.3
.1
- 0.3
.1)
OPERATING SCHEDULES:
Schedule A: 6 hours idling; 2 hours working; 16 hours downtime; 5 days/week; 52 weeks/year
Schedule B: 4 hours idling; 12 hours working; 8 hours downtime; 5 days/week; 52 weeks/year
-------
Table 5-6. SUMMARY OF RETROFIT CONTROL COSTS AND COST EFFECTIVENESS FOR MODEL OTVC's
USING TRICHLOROETHYLENE (1988 J)
en
i
ro
1.
2.
3.
4.
5.
6.
Control Option
Automated Parts Handling System 811 fpm;
Below-freezing FRD; 1.0 FBR
Automated Parts Handling System 811 fpm;
Enclosed Design; Sump Cooling
Automated Parts Handling System 311 fpm;
Automated Bi -parting Cover
Automated Parts Handling System a 3 fpm
Below-freezing FRD; 1.0 FBR
Automated Parts Handling System a 3 fpm;
Enclosed Design; Sump Cooling
Automated Parts Handling System a 3 fpm;
Automated Bi -part ing Cover
Cleaner
Size/
Operating
Schedule
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
Total
Installed
Capital Cost
(*)
8,180
6.180
15,200
15,200
6,220
6,220
U.700
1,470
10,200
10,220
14,500
14.500
8,680
8,680
15,700
15,700
6.720
6.720
15.200
15.200
10.700
10.700
15.000
15.000
Total
Annuali zed Emission
Cost Reduction
($/yr) (Ib/yr)
2,200
2,770
3,630
4,200
1,820
1,790
3,740
3,640
2,090
2,200
2.980
3,160
2,300
2,880
3,740
4,310
1,920
1,890
3,840
3.750
2.200
2,300
3,080
3.260
1,160- 1,440
3,470- 4,860
4,110- 5,130
12.300-17.300
2,020- 2,310
4,860- 5,550
7,190- 8,210
17,300-19,700
870- 1,160
3,470- 4,160
3,080- 4,110
12,300-14,800
1,440- 1,730
5.550
5,130- 6,160
19,700
2,310- 2.600
6,240
8.210- 9.240
22,200
1,160- 1,440
5.550
4,110- 5,130
19,700
Recovered
Solvent
Credit
(*/yr)
(440)-(560)
(1,340)-<1.870)
(1,580)-(1.980)
(4,750)-(6,650)
(780)-(890)
(1,870)-(2,140)
(2.770)-(3,160)
(6,650)-(7,600)
(330)-(450)
(1,340)-(1,600)
(1,190)-(1.580)
(4,750)-(5,700)
(560) -(670)
(2,140)
(1,980)-(2.370)
(7,600)
(890)-(1,000)
(2.400)
(3,160)-(3,560)
(8,550)
(450)-(560)
(2.UO)
(1.580)-(1,980)
(7,600)
Net
Annualized
Cost
(*/yr)
1.760- 1,650
1,440- 900
2.050- 1,660
(540)-(2,440)
1,040- 930
(80)- (350)
970- 570
(3,000)-(3,950)
1.760- 1,650
860- 600
1.790- 1,400
(1,580)-(2,540)
1,750- 1,640
740
1,760- 1,360
(3.290)
1,030- 920
(510)
680- 280
(4,800)
1,750- 1,640
160
1.500- 1,105
(4.330)
Cost
Effectiveness
($/lb)
1.5 - 1.1
0.4 - 0.2
0.5 - 0.3
(0.04)-(0.14)
0.5 - 0.4
(0.02)-(0.06)
0.1 - 0.07
(0.2)-(0.2)
2.0 - 1.4
0.2 - 0.1
0.6 - 0.3
(0.1)-(0.2)
1.2 - 1.0
0.1
0.3 - 0.2
(0.01)
0.5 - 0.4
(0.1)
0.1 - 0.03
(0.2)
1.5 - 1.1
(0.03)
0.4 - 0.2
(0.2)
OPERATING SCHEDULES:
Schedule A: 6 hours idling; 2 hours working; 16 hours downtime; 5 days/week; 52 weeks/year
Schedule B: 4 hours idling; 12 hours working; 8 hours downtime; 5 days/week; 52 weeks/year
-------
Table 5-7. SUMMARY OF RETROFIT CONTROL COSTS AND COST EFFECTIVENESS FOR MODEL OTVC's
USING 1.1.1-TRICHLOROETHANE (1988 $)
ro
ro
1.
2.
3.
4.
5.
6.
for
Control Option
Automated Parts Handling System 311 fpm;
Below-freezing FRD; 1.0 FBR
Automated Parts Handling System 911 fpm;
Enclosed Design; Sump Cooling
Automated Parts Handling System 311 fpm;
Automated Bi-parting Cover
Automated Parts Handling System 8 3 fpm
Below-freezing FRD; 1.0 FBR
Automated Parts Handling System 3 3 fpm;
Enclosed Design; Sump Cooling
Automated Parts Handling System 3 3 fpm;
Automated Bi-parting Cover
Cleaner
Size/
Operating
Schedule
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ftZ/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/B
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
Total
Installed
Capital Cost
(J)
8,180
8,180
15,200
15,200
6,220
6,220
14,700
1.470
10,200
10.220
14,500
14,500
8,680
8,680
15,700
15,700
6,720
6,720
15,200
15.200
10,700
10,700
15,000
15,000
Total
Annual ized
Cost
(*/yr)
2.200
2.770
3,630
4,200
1,820
1,790
3,740
3,640
2,090
2,200
2,980
3,160
2,300
2,880
3,740
4,310
1.920
1.890
3,840
3,750
2.200
2,300
3,080
3,260
Emission
Reduction
(Ib/yr)
1,160- 1,440
3,470- 4,860
4,110- 5,130
12.300-17,300
2,020- 2,310
4,860- 5,550
7,190- 8,210
17,300-19,700
870- 1,160
3,470- 4,160
3,080- 4,110
12,300-14,800
1,440- 1,730
5,550
5,130- 6,160
19,700
2,310- 2.600
6.240
8,210- 9,240
22,200
1.160- 1,440
5,550
4,110- 5,130
19,700
Recovered
Solvent
Credit
(*/yr)
(470)-(580)
(1,400)-(1.970)
(1,660)-(2,080)
(4.990)-<6.990)
(820)-(940)
(1.970)-(2.250)
(2,910)-<3.330)
Net
Annual ized
Cost
(«/yr)
1.740-1.620
1,370-810
1,970-1.560
(790)-(2.790)
1,000-890
(180)-(460)
820-410
(6,990)-(7,990) (3,350)-(4,340)
(350)-(470)
(1,400)-(1.690)
(1,250)-(1.660)
(4,990)-(5,990) (1
(580)-(700)
(2.250)
(2,080)-(2,500)
(7,600) (3
(940)-(1,050)
(2.530)
(3.330)-<3,740)
(8.990)
(470)-(580)
(2.250)
(1,660)-(2,080)
(7.990)
1.740-1,620
820-510
1,730-1.320
,830)-(2,830)
1,720-1,600
630-350
1,660-1,240
,680)-(4,680)
900-870
(640)
510-100
(5,240)
1,730-1,610
50
1,420-1.000
(4.730)
Cost
Effectiveness
(S/lb)
1.5 - 1.1
0.4 - 0.2
0.5 - 0.3
(0.1) -(0.2)
0.5 - 0.4
(0.04)-(0.1)
0.1 - 0.05
(0.2)-{0.2)
2.0 - 1.4
0.2 - 0.1
0.6 - 0.3
(0.1)-(0.2)
1.2 - 0.9
0.1
0.3 - 0.2
(0.2)
0.4 - 0.3
(0.1)
0.06 - 0.01
(0.2)
1.5 - 1.1
0.01
0.4 - 0.2
(0.2)
OPERATING SCHEDULES:
Schedule A: 6 hours idling; 2 hours working; 16 hours downtime; 5 days/week; 52 weeks/year
Schedule B: 4 hours idling; 12 hours working; 8 hours downtime; 5 days/week; 52 weeks/year
-------
Table 5-8. SUMMARY OF RETROFIT CONTROL COSTS AND COST EFFECTIVENESS FOR MODEL OTVC's
USING TRICHLOROTRIFLOUROETHANE (1988 $)
ro
OJ
1.
2.
3.
4.
5.
6.
Control Option
Automated Parts Handling System 311 fpm;
Below- freezing FRD; 1.0 FBR
Automated Parts Handling System 311 fpm;
Enclosed Design; Sump Cooling
Automated Parts Handling System 311 fpm;
Automated Bi -part ing Cover
Automated Parts Handling System 3 3 fpm
Below-freezing FRD; 1.0 FBR
Automated Parts Handling System 3 3 fpm;
Enclosed Design; Sump Cooling
Automated Parts Handling System 3 3 fpm;
Automated Bi -parting Cover
Cleaner
Size/
Operating
Schedule
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/B
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
4.5ft2/A
4.5ft2/B
16 ft2/A
16 ft2/B
Total Total
Installed Annualized Emission
Capital Cost Cost Reduction
(«) ($/yr) (Ib/yr)
8,180
8,180
15,200
15.200
6.220
6,220
14,700
1.470
10,200
10.220
14,500
14,500
8,680
8,680
15.700
15.700
6,720
6,720
15,200
15,200
10.700
10.700
15.000
15.000
2,200
2.770
3.630
4,200
1,820
1,790
3.740
3.640
2.090
2.200
2.980
3.160
2,300
2,880
3.740
4,310
1.920
1,890
3,840
3,750
2.200
2,300
3,080
3.260
1,160- 1,440
3,470- 4,860
4,110- 5,130
12,300-17,300
2,020- 2,310
4,860- 5,550
7,190- 8,210
17.300-19,700
870- 1,160
3,470- 4,160
3,080- 4.110
12,300-14,800
1,440- 1,730
5.550
5,130- 6,160
19,700
2,310- 2,600
6,240
8.210- 9,240
22.200
1.160- 1.440
5.550
4,110- 5,130
19.700
Recovered
Solvent
Credit
(*/yr)
(1,040)-(1.300)
(3,120)-(4.370)
(3,700)-(4,620)
(11,100)-(15.500)
(1,820)-(2,080)
(4.370)-(4,990)
(6.470)-(7,390)
(15,500)-(17.800)
(780)-(1,040)
(3,120)-(3,750)
(2,770)-(3,700)
(11,100)-(13,330)
(1,300)-(1,560)
(4.990)
(4,620)-(5,540)
(17,800)
(2.080)-(2,340)
(5,620)
(7,390)-(8,320)
(20,000)
(1,040)-(1,300)
(4,490)
(3,700)-(4,620)
(17,800)
Net
Annualized
Cost
(S/yr)
1.160-900
(350)-(1,600)
(60)-(990)
(6,890)-(11,300)
0-(260)
(2,580)-(3.200)
(2,730)-(3,660)
(11.900)-(14,100)
1,310-1,050
(920)-(1.550)
210-(720)
(7,940)-(10,200)
1,000-750
(2,120)
(890)-(1,810)
(13,500)
(160)-(420)
(3,730)
(3,S60)-(4,480)
(16,200)
1,160-900
(2,690)
(620)-(1,540)
(14,500)
Cost
Effectiveness
1
(0
(0
(0
0
(0
(0
(0
1
(0
0
(0
0
(0
(0
(0
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(0
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.0 -
.4)-
.7)-
.5 -
.1 -
.6)-
.7 -
(0.
(0.
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(0.
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(0.
'(0.
0.
6
-(0.2)
(0.
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(0.
0.
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0.
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7)"
(0.
6)
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0.
5)
7)"
7)
1)
5)
7)
9
2)
4
3)
2)
5)
6
2)
freeboard refrigeration device
OPERATING SCHEDULES:
Schedule A: 6 hours idling; 2 hours working; 16 hours downtime; 5 days/week; 52 weeks/year
Schedule B: 4 hours idling; 12 hours working; 8 hours downtime; 5 days/week; 52 weeks/year
-------
annualized costs. As a result, cost effectiveness values are lower for the
higher priced solvents. The highest priced solvent, CFC-113, shows net
annualized credits for a larger number of control options than with the other
solvents. However, all solvents have credits for at least some options. For
all control options and all solvents, the net annualized costs and cost
effectiveness values are lower for OTVC's operating at Schedule B (where there
is more working time and less idle time). This is due to the added emission
reduction at no additional capital costs.
The option requiring an automated parts handling system operating at
3 fpm (through the vapor zone), an enclosed design, and sump cooling (Control
Option 5) is generally the most cost-effective option for the small OTVC
(Schedule A and B) and the large OTVC (Schedule A, .only). The next most
cost-effective control option is Control Option 2, which is identical to
Control Option 5 except the speed of the automated parts handling system when
parts are within the vapor zone is 11 fpm. In most instances, the two control
options for these OTVC's with the highest cost effectiveness values include an
automated parts handling system operating at 11 fpm and either a
below-freezing freeboard refrigeration device and 1.0 FBR or a bi-parting
cover (Control Options 1 and 3, respectively).
The ranking of the control options changes slightly for a large OTVC
operating under Schedule B. It is noted that adding controls on these larger
machines operating under a heavier working schedule produce annualized net
credits in almost all instances, the exception being for Control Option 1 (and
only then when the lower end of the control efficiency range is assumed). The
highest net annualized credits for this model cleaner are for Control Option 5
5-24
-------
(as with other OTVC models) and Control Option 6, the use of a bi-parting
automated cover in addition to an automated parts handling system operating at
3 fpm through the vapor zone.
5.4 IN-LINE CLEANERS
5.4.1 Model Cleaner Parameter;
In-line cleaners are generally greater than 20 ft2 in the air/solvent
vapor interface area and can be either vapor or cold cleaning operations. In
order to examine the impacts of potential emission controls on both types of
cleaners, a model cleaner with a solvent air interface of 38 ft2 was selected.
This model was used to represent both cold and vapor cleaners; the only
in-line cold cleaners encountered during data gathering use MC in photoresist
stripping operations. The model cleaner parameters for in-line'cleaners are
presented in Table 5-9. These parameters are based on industry contacts and
EPA studies of the solvent cleaning industry. Two operating schedules were
examined to evaluate the range of conditions that exist in the cold and vapor
in-line cleaner market. There is no idling time in either in-line schedule.
It is assumed that once the machine is turned on, parts will be continuously
cycled through the machine until the end of the shift(s). If the continuous
processing were not required, it is assumed solvent cleaner operators would
choose the less expensive OTVC.
Uncontrolled emissions were calculated based on the amount of time the
cleaner is operating and down. Uncontrolled emissions from the in-line model
cleaner ranged from 47,100 Ib/year under operating Schedule A to
114,000 Ib/year under Schedule B.
5-25
-------
TABLE 5-9. MODEL CLEANER PARAMETERS FOR IN-LINE CLEANERS
cn
rv>
Oi
Parameter
Working area, ft
Solvent
Operating schedule he/year
Working
Downtime
Uncontrolled emission rates (b/hr
Working
Downtime
Uncontrolled emissions8 (Ib/yr)
Working
Downtime
Total
Control Option . 13
Controlled emissions (Ib/yr) 23600 23600
Totalc
Emission Reduction 23600 23600
Uncontrolled emissions based port covers in downtime.
Controlled emissions based on the following:
Control Option 1: Below-freezing FRD
Control Option 2: Carbon Adsorber
Control Option 3: Below-freezing FRD; Sump Cooling
Control Option 4: Carbon Adsorption; Sump Cooling
Control Option 5: Super Heated Vapor; Sump Cooling
Control Option 6: Below-freezing FRD; Super Heated Vapor
In- Line - Schedule A
38.0
All
2080
6656
19
1.14
39520
7588
47100
3456
16500 16500 14100 14100
30600 30600 33000 33000
Efficiency (X)
50
50
65
65
70
70
NOTE
All reported efficiencies are for control of idling, working, and downtime losses only. They do not account for leaks
wastewater losses, or transfer losses which should be minimal if proper practices are employed. '
FRD - Freeboard refrigeration devices
FBR - Freeboard ratio
-------
TABLE 5-9. MODEL CLEANER PARAMETERS FOR IN-LINE CLEANERS (Continued)
en
rv>
Parameter
Working area, ft
Solvent
Operating schedule hr/year
Working
Downtime
Uncontrolled emission rates Ib/hr
Working
Downtime
Uncontrolled emissions8 (Ib/yr)
Working
Downtime
Total
Control Strategy . 123
Controlled emissions (Ib/yr) 45600 45600 45600
Total0
Emission Reduction 68400 68400 68400
Uncontrolled emissions based on 0.75 F8R, port covers in downtime.
Controlled emissions based on the following:
Control Option 1: Below-freezing FRD
Control Option 2: Carbon Adsorber
Control Option 3: Below-freezing FRD; Sump Cooling
Control Option 4: Carbon Adsorption; Sump Cooling
Control Option 5: Super Heated Vapor; Sump Cooling
Control Option 6: Below-freezing FRD; Super Heated Vapor
In-Line - Schedule B
38.0
All
5824
2912
19
1.14
111000
3320
114000
456
45600 17100 17100
68400 96900 96900
Efficiency (X)
60
60
60
60
85
85
Range based on range of Control Efficiencies
NOTE: All reported efficiencies are for control of idling, working, and downtime losses only. They do not account for leaks,
wastewater losses, or transfer losses which should be minimal if proper practices are employed.
FRD - Freeboard refrigeration devices
FBR - Freeboard ratio
-------
When calculating controlled emissions, no emission reduction or control
cost was included for limiting the conveyor speed to 11 fpm since this is
assumed to be occurring at baseline. The following five control options were
considered as control alternatives:
• Control Option 1: a below-freezing freeboard refrigeration device;
• Control Option 2: a carbon adsorption system;
t Control Option 3: below-freezing freeboard refrigeration device
and sump cooling;
t Control Option 4: a carbon adsorption system and sump cooling;
• Control Option 5: a super-heated vapor system and sump cooling; and
t Control Option 6: a below-freezing freeboard refrigeration device
and super-heated vapor.
Due to the limited downtime in Schedule B, sump cooling has a relatively small
effect on overall control efficiency. Therefore, only Control Options 1
through 3 and Control Option 6 are evaluated for this model.
Efficiencies were calculated based on existing test data. The
efficiencies are summarized at the bottom of Table 5-9. Under Schedule A,
Control Option 5 is the most effective, reducing total emissions by
70 percent. Under Schedule B, super-heated vapor (Control Option 3) reduces
emissions by 70 percent, while the other controls reduce emissions by 60
percent.
5-28
-------
5.4.2 Cost Evaluation
Table 5-10 presents the capital costs, annual operating costs, emission
reduction, solvent recovery credit, net annualized costs, and cost
effectiveness of retrofitting each of the control options on an in-line
cleaner using MC. Tables 5-11 through 5-14 summarize this information for
PCE, TCE, TCA, and CFC-113, respectively. The tables detailing these costs
(and presenting the values for new in-lines) are presented in Appendix C-3.
As with OTVC's, the only variable among the calculations for each solvent
was the solvent price (listed in Table 5-2). Therefore, the higher priced
solvents have higher solvent recovery credits and, therefore, lower net
annualized costs. As a result, cost effectiveness.values are lower for the
higher priced solvents. The highest priced solvent, CFC-113, shows net
annualized credits for a larger number of control options than with the other
solvents. For all control options and all solvents, the net annualized costs
and cost effectiveness values are lowest for in-line cleaners operating under
Schedule B. This effect is caused by achieving additional emission reduction
under the longer operating schedule without incurring additional capital
costs.
The addition of sump cooling during downtime has only a slight effect on
cost effectiveness values of the same major control without sump cooling. In
some cases, costs actually increase with the addition of sump cooling. All
in-line control options, with the exception of a carbon adsorber (Control
Option 2) always provided a net annualized credit. A credit for Control
Option 2 only occurred for CFC-113 with Schedule B operation. The highest
credit control for in-lines is the super-heated vapor system with sump cooling
(Control Option 5).
5-29
-------
Table 5-10. SUMMARY OF RETROFIT CONTROL COSTS AND COST EFFECTIVENESS FOR MODEL IN-LINE CLEANERS
USING METHYLENE CHLORIDE (1988 S)
in
i
00
o
Control Option
1. Below Freezing FRD
2. Carbon Adsorber
3. Below-freezing FRD; Sump Cooling
4. Carbon Adsorber; Sump Cooling
5. Super Heated Vapor; Sump Cooling
6. Below-freezing FRD; Sump Cooling
Cleaner
Size/
Operating
Schedule
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
Total
Instal led
Capital Cost
($)
18.500
18.500
80,500
80,500
20,000
20,000
82,000
82,000
5,040
5,040
22,100
22,100
Total
Annual ized
Cost
(S/yr)
3,900
5,200
23,600
36,800
5,100
6,210
25,000
37,800
2.530
3,640
5,230
7,820
Emission
Reduction
(Ib/yr)
23,600
68,400
23,600
68,400
30,600
68,400
30,600
68,400
33,000
96,900
33.000
96,900
Recovered
Solvent
Credit
(*/yr)
(6.100)
(17.700)
(6,100)
(17,700)
(9.490)
(17,700)
(7,390)
(17,700)
(8,540)
(25.100)
(8.540)
(25.100)
Net
Annual ized
Cost
(*/yr)
(2,200)
(12.500)
17,500
19,100
(2.830)
(11,500)
17,000
20,100
(6,020)
(21,500)
(3,130)
(17.300)
Cost
Effectiveness
($/lb)
(0.1)
(0.2)
0.7
0.3
(0.2)
(0.2)
0.6
0.3
(0.2)
(0.2)
(0.1)
(0.2)
OPERATING SCHEDULES:
Schedule A: 8 hours working; 16 hours downtime;
Schedule B: 16 hours working; 8 hours downtime;
5 days/week; 52 weeks/year
7 days/week; 52 weeks/year
-------
Table 5-11. SUMMARY OF RETROFIT CONTROL COSTS AND COST EFFECTIVENESS FOR MODEL IN-LINE CLEANERS
USING PERCHLOROETHYLENE (1988 S)
u>
Total Total Recovered Net
Installed Annualized Emission Solvent Annualized
Cleaner Size/ Capital Cost Cost Reduction Credit Cost
1.
2.
3.
4.
5.
6.
Control Option
Below Freezing FRD
Carbon Adsorber
Below- freezing FRD; Sump Cooling
Carbon Adsorber; Sump Cooling
Super Heated Vapor; Sump Cooling
Below- freezing FRD; Sump Cooling
Operating Schedule ($) ($/yr) (Ib/yr) (S/yr)
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
18.500
18,500
80,500
80,500
20.000
20.000
82,000
82,000
5,040
5,040
22,100
22,100
3.900
5.200
23,600
36,800
5,100
6,210
25,000
37,800
2,530
3.640
5,230
7,820
23,600
68,400
23,600
68.400
30,600
68,400
30,600
68.400
33.000
96.900
33,000
96.900
(7.300)
(21,200)
(7.300)
(21.200)
(9.490)
(21.200)
(9.490)
(21.200)
(10,200)
(30,000)
(10.200)
(30,000)
(*/yr)
(3,400)
(16,000)
16,300
15,600
(4.780)
(15.000)
15,500
16,600
(6,840)
(26,400)
(4,990)
(22,200)
Cost
Effectiveness
(*/lb)
(0.1)
(0.2)
0.7
0.2
(0.2)
(0.2)
0.6
0.2
(0.2)
(0.3)
(0.2)
(0.2)
FRD = freeboard refrigeration device
OPERATING SCHEDULES:
Schedule A: 8 hours working; 16 hours downtime;
Schedule B: 16 hours working; 8 hours downtime;
5 days/week; 52 weeks/year
7 days/week; 52 weeks/year
-------
Table 5-12. SUMMARY OF RETROFIT CONTROL COSTS AND COST EFFECTIVENESS FOR MODEL IN-LINE CLEANERS
USING TR1CHLOROETHYLENE (1988 $)
Cleaner Size/
Total Total
Installed Annual ized Emission
Capital Cost Cost Reduction
Control Option Operating Schedule ($)
1. Below Freezing FRO
2. Carbon Adsorber
3. Below-freezing FRD; Sump Cooling
i>. Carbon Adsorber; Sump Cooling
5. Super Heated Vapor; Sump Cooling
en
co 6. Below-freezing FRD; Sump Cooling
ro
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
38 ft2/A
38 ft2/B
18,500
18,500
80,500
80,500
20,000
20,000
82,000
82,000
5,040
5,040
22,100
22,100
(*/yr)
3,900
5,200
23,600
36,800
5,100
6,210
25.000
37,800
2,530
3,640
5,230
7,820
(Ib/yr)
23,600
68,400
23,600
68,400
30,600
68,400
30,600
68,400
33,000
96,900
33,000
96,900
Recovered
Solvent
Credit
($/yr)
(9,070)
(26,300)
(9.070)
(26,300)
(11,800)
(26,300)
(11,800)
(26,300)
(12.700)
(37,300)
(12,700)
(37.300)
Net
Annual ized Cost
Cost Effectiveness
(S/yr)
(5.170)
(21.100)
14,500
10.500
(7.080)
(20,100)
13.200
11.500
(9.310)
(33,700)
(7,470)
(29.500)
(S/lb)
(0.2)
(0.3)
0.6
0.2
(0.2)
(0.3)
0.4
0.2
(0.3)
(0.4)
(0.2)
(0.3)
OPERATING SCHEDULES:
Schedule A: 8 hours working; 16 hours downtime;
Schedule B: 16 hours working; 8 hours downtime;
5 days/week; 52 weeks/year
7 days/week; 52 weeks/year
-------
Table 5-13. SUMMARY OF RETROFIT CONTROL COSTS AND COST EFFECTIVENESS FOR MODEL IN-LINE CLEANERS
USING 1,1,1-TRICHLOROETHANE (1988 $)
Total Total Recovered
Installed Annual ized Emission Solvent
Cleaner Size/ Capital Cost Cost Reduction Credit
Control Option Operating Schedule (*) (Vyr) (Ib/yr) (t/yr)
1. Below Freezing FRD 38 ft2/A
38 ft2/B
2. Carbon Adsorber 38 ft2/A
38 ft2/B
3. Below-freezing FRD; Sump Cooling 38 ft2/A
38 ft2/B
it. Carbon Adsorber; Sump Cooling 38 ft2/A
38 ft2/B
in
to 5. Super Heated Vapor; Sump Cooling 38 ft2/A
00 38 ft2/B
6. Be low- freezing FRD; Sump Cooling 38 ft2/A
38 ft2/B
18,500
18,500
80,500
80,500
20,000
20,000
82,000
82,000
5,040
5,040
22,100
22,100
3,900
5,200
23,600
36,800
5,100
6,210
25,000
37,800
2,530
3,640
5,230
7,820
23,600
68,400
23,600
68,400
30,600
68,400
30,600
68,400
33,000
96,900
33,000
96,900
(9.540)
(27.700)
(9.540)
(27,700)
(12,400)
(27.700)
(12.400)
(27.700)
(13.400)
(39,200)
(13,400)
(39,200)
Net
Annual ized Cost
Cost Effectiveness
(*/yr) (S/lb)
(5,640)
(22,500)
14,100
9,090
(7,300)
(21.500)
12,600
10.100
(9,970)
(35,600)
(8,130)
(31,400)
(0.2)
(0.3)
0.6
0.1
(0.2)
(0.3)
0.4
0.2
(0.3)
(0.9)
(0.2)
(0.8)
FRD = freeboard refrigeration device
OPERATING SCHEDULES:
Schedule A: 8 hours working; 16 hours downtime;
Schedule B: 16 hours working; 8 hours downtime;
5 days/week; 52 weeks/year
7 days/week; 52 weeks/year
-------
Table 5-14. SUMHARY OF RETROFIT CONTROL COSTS AND COST EFFECTIVENESS FOR HODEL IN-LIME CLEANERS
USING TRICHLOROTR1FLOUROETHANE (1988 $)
en
i
CO
1.
2.
3.
4.
5.
6.
?i»r
Control Option
Below Freezing FRD
Carbon Adsorber
Below-freezing FRD; Sump Cooling
Carbon Adsorber; Sump Cooling
Super Heated Vapor; Sump Cooling
Below-freezing FRD; Sump Cooling
Total Total Recovered
Installed Annuatized Emission Solvent
Cleaner Size/ Capital Cost Cost Reduction Credit
Operating Schedule ($) ($/yr) (Ib/yr) ($/yr)
38
38
38
38
38
38
38
38
38
38
38
38
ft2/A
ft2/B
ft2/A
ft2/8
ft2/A
ft2/B
ft2/A
ft2/B
ft2/A
ft2/B
ft2/A
ft2/B
18,500
18,500
80,500
80,500
20,000
20,000
82,000
82.000
5,040
5,040
22,100
22,100
3,900
5,200
23,600
36,800
5,100
6,210
25,000
37,800
2,530
3,640
5,230
7,820
23.600
68,400
23,600
68,400
30,600
68,400
30,600
68,400
33,000
96,900
33,000
96,900
(21.200)
(61,
(21,
(61,
(27,
(61.
(27.
(61.
(29.
(87.
(29.
(87.
500)
200)
500)
690)
500)
600)
500)
700)
200)
700)
200)
Net
Annualized Cost
Cost Effectiveness
(*/yr) (S/lb)
(17.300)
(56.300)
2
(24
(22
(55
(2
(23
(26
(83
(24
(79
,400
,800)
,500)
,300)
,590)
,700)
.300)
.500)
,500)
,400)
(0.7)
(0.8)
0 1
(0.4)
(0.7)
(0.8)
(0.1)
(0.4)
(0.8)
(0.9)
(0.7)
(0.8)
OPERATING SCHEDULES:
Schedule A: 8 hours working; 16 hours downtime;
Schedule B: 16 hours working; 8 hours downtime;
5 days/week; 52 weeks/year
7 days/week; 52 weeks/year
-------
5.5 REFERENCES
1. Letter and attachments from Philip J. Feig, Branson Ultrasonics
Corporation, to Jack R. Farmer, U. S. Environmental Protection Agency.
February 16, 1987. Section 114 organic solvent cleaner vendor
questionnaire response.
2. Letter and attachments from Algar Saulic, Baron-Blakeslee, Incorporated
to Jack R. Farmer, U. S. Environmental Protection Agency. March 9, 1987,
Section 114 organic solvent cleaner vendor questionnaire response.
3. Letter and attachments from Henry Stanley, Unique Industries to
Jack R. Farmer, U. S. Environmental Protection Agency. April 15, 1987.
Section 114 organic solvent cleaner vendor questionnaire response.
4. Letter and attachments from Joseph Scapelliti, Detrex Corporation, to
Jack R. Farmer, U. S. Environmental Protection Agency. April 15, 1987.
Section 114 organic solvent cleaner vendor questionnaire response.
5. Letter and attachments from Robert E. Miller, Westinghouse Electric
Corporation, to David A. Beck, U. S. Environmental Protection Agency.
June 5, 1987. Section 114 response.
6. Letter and attachments from Oskar Franz, Phillips Manufacturing Company
to Jack Farmer, U. S. Environmental Protection Agency. June 18, 1987.
Section 114 organic solvent cleaner vendor questionnaire response.
7. Letter and attachments from Jon Harman, Branson Cleaning Equipment
Company, to Jack R. Farmer, U. S. Environmental Protection Agency.
May 5, 1987. Follow-up questions to Section 114 vendor questionnaire
response.
8. Telephone Conversation. Beck, David, U. S. Environmental Protection
Agency, with Joseph Scapelliti, Detrex Corporation. May 17 - 18, 1987.
Follow-up questions to Section 114 vendor questionnaire response.
9. Telephone Conversation. Pandullo, Rich, Radian Corporation, with
Henry Stanley, Unique Industries. June 4, 1987. Clarifications to
Section 114 organic solvent cleaner vendor questionnaire.
10. Telephone Conversation. Pandullo, Rich, Radian Corporation, with
Jon Harman, Branson Cleaning Equipment. May 29, 1987. Information on
freeboard ratios and refrigerated chillers for OTVC's.
11. Telephone Conversation. Pandullo, Rich, Radian Corporation, with
Oskar Franz, Phillips Manufacturing Company. May 29, 1987. Information
on freeboard ratios and refrigerated chillers for OTVC's.
5-35
-------
5.5 REFERENCES
12. Telephone Conversation. Lear, Judith, Radian Corporation, with
Jim Bennett-Elias, Baron-Blakeslee. June 1, 1987. Follow-up questions
to Section 114 vendor questionnaire response.
13. Telephone Conversation. Lear, Judith, Radian Corporation, with
Joe Scapeleti, Detrex Corporation. June 3, 1987. OTVC - percent sold
with refrigerated freeboard chillers.
14. Telephone Conversation. Lear, Judith, Radian Corporation, with
Jim Bennett-Elias, Baron-Blakeslee. June 15, 1987. Follow-up questions
to Section 114 vendor questionnaire response.
15. Letter and attachments from Algar Saulic, Baron-Blakeslee, Incorporated,
to Judith Lear, Radian Corporation. June 16, 1987. Section 114 organic
solvent cleaner vendor questionnaire response.
16. Telephone Conversation. Miller, Susan, Radian Corporation, with
Jon Harman, Branson. June 19, 1987. Follow-up questions to Section 114
vendor questionnaire response.
17. Telephone Conversation. Miller, Susan, Radian-Corporation, with
Jon Harman, Branson. July 1, 1987. Follow-up questions to Section 114
vendor questionnaire response.
18. Telephone Conversation. Miller, Susan, Radian Corporation, with
Henry Stanley, Unique Industries. July 24, 1987. Clarifications on
response to vendor questionnaire.
19. Telephone Conversation. Miller, Susan, Radian Corporation, with
Jon Harman, Branson. July 27, 1987. Follow-up questions to Section 114
vendor questionnaire response.
20. Telephone Conversation. Miller, Susan, Radian Corporation, with
Jim Bennet-Elias, Baron-Blakeslee, Incorporated. July 27, 1987.
Follow-up questions to Section 114 vendor questionnaire response.
21. Telephone Conversation. Miller, Susan, Radian Corporation, with
Oskar Franz, Phillips Manufacturing. July 27, 1987. Clarifications on
response to vendor questionnaire.
22. Telephone Conversation. Miller, Susan, Radian Corporation, with
John Tress, Westinghouse. July 29, 1987. Follow-up questions to
Section 114 vendor questionnaire response.
23. Telephone Conversation. Beck, D. A., U. S. Environmental Protection
Agency, with Joseph Scapelliti, Detrex Corporation. Follow-up questions
to Section 114 vendor questionnaire response.
5-36
-------
5.5 REFERENCES
24. Telephone Conversation. Rhodes, L. M., Radian Corporation, with O'Neil,
Orane, Baron-Blakeshlee. January 26, 1989. Information on OTVC costs.
25. Telephone Conversation. Rhodes, L. M., Radian Corporation, with
Selznick, R., Baron-Blakeshlee. January 26, 1989. Information on OTVC
and in-line costs.
26. Telephone Conversation. Rhodes, L. M., Radian Corporation, with
Astrota, J., Baron-Blakeshlee. January 26, 1989. Information on OTVC
and in-line costs.
27. Telephone Conversation. Rhodes, L. M., Radian Corporation, with
Uffer, W., Detrex Corporation. January 26, 1989. Information on
in-line costs.
28. Telephone Conversation. Rhodes, L. M., Radian Corporation, with
Aldridge, J., Scarex Corporation. January 27, 1989. Information on
OTVC and in-line costs.
29. Telephone Conversation. Rhodes, L. M., Radian Corporation, with
Racqiet, D., Phillips. January 27, 1989. Information on OTVC and
in-1ine costs.
30. Telephone Conversation. Miller, S. J., Radian Corporation, with
Gilliam, A., Unique Industries. February 13, 1989. Information on
OTVC and in-line costs.
31. Telephone Conversation. Miller, S. J., Radian Corporation, with
Halbert, J., Delta Sonics. February 13, 1989. Information on OTVC and
in-line costs.
32. Reference 1.
33. Reference 2.
34. Reference 4.
35. Reference 2.
36. Reference 3.
37. Reference 4.
38. U. S. Environmental Protection Agency. Control Cost Manual. Research
Triangle Park, North Carolina. Publication No. EPA 450/5-87-001A.
February 1987. page 4-34.
39. Chemical Profile, Chemical Marketing Reporter, February 3, 1986.
5-37
-------
5.5 REFERENCES
40. Chemical Profile, Chemical Marketing Reporter, February 6, 1989.
41. Chemical Profile, Chemical Marketing Reporter, January 23, 1989.
42. Chemical Profile, Chemical Marketing Reporter, January 30, 1989.
43. "Fluorocarbon Solvents" Chemical Products Synopsis, October 1984.
44. U. S. Department of Energy. Monthly Energy Review. Washington, D.C.
Publication Number DOE/EIA-0035 (86/11). November 1986.
45. Memorandum. May, P. A., Radian Corporation, to Butadiene Source
Category Concurrence4 File. Batch Flare Algorithm and TRE Development.
December 31, 1986.
46. U. S. Environmental Protection Agency. Organic Solvent Cleaners --
Background Information for Proposed Standards. Office of Air Quality
Planning and Standards. Research Triangle Park, North Carolina.
Publication No. EPA 450/2-78-045a. October 1979. page 8-39.
47. GARD, Inc. Capital and Operating Costs of Selected Air Pollution
Control Systems. Prepared for U. S. Environmental Protection Agency.
Research Triangle Park, North Carolina. Publication No.
EPA-450/5-80-002. 1978. page 3-12.
48. Reference 46.
49. BLS Producer Price Index. All Industiral Commodities. File 176 Dinlog
Information Services, Inc. February 10, 1989 update.
50. CE plant cost index for building, Chemical Engineering. May 23, 1981.
p. 7.
51. CE plant cost index for building, Chemical Engineering. July 23, 1981.
p. 7.
52. CE plant cost index for building, Chemical Engineering.
January 16, 1989. p. 186.
5-38
-------
APPENDIX A
DERIVATION OF COMBINED
EFFICIENCY FORMULA
A-l
-------
APPENDIX A
The efficiencies for individual control techniques discussed in
Chapter 4.0 are based on the single control technique being added to a solvent
cleaner. When two or more control techniques act upon the same solvent
emissions (i.e., idling, working), the combined efficiency of these techniques
added to one cleaner is not equivalent to the direct sum of the individual
efficiencies for each technique. The combined efficiency of two or more
controls is somewhat less than the additive sum. This is because the
additional techniques are essentially controlling only the emissions not
already controlled by the first technique (i.e., the control techniques are
essentially acting in series). The derivation of combined efficiency formulas
for two control techniques and three control techniques, respectively, are
described below.
Combined Efficiency Formula for Two Control Techniques
1. Let,
B = baseline emissions (no control)
Ej = removal efficiency for control 1 only
E2 = removal efficiency for control 2 only
2. Then,
BEj = amount of baseline emissions reduction using control 1
3. B - BEj = amount of baseline emissions remaining after application
of control 1
4. EgiB - BEj) = emission reduction control 2 acting on remaining
emissions
5. Total Emission Reduction
= BEj + E2(B - BEj)
- BEj + BE2 - BEjE2
= B[Ej + E2 - EjE2]
A-2
-------
6. The effective removal efficiency (E^pp) of control 1 and control 2
acting simultaneously on the baseline emissions (B) is, therefore,
EEFF " El + E2 - E1E2
Combined Efficiency formula for Three Control Techniques
1. Let,
B = baseline emissions (no control)
E, = removal percent for control 1 only
E« = removal percent for control 2 only
E3 = removal percent for control 3 only
2. Then,
BE, = amount of baseline emissions reduction using control 1
3. B - BE, * amount of emission remaining after application of control 1
4. (B - BE,)E2 = amount of emission reduction using control 2
5. B - BE, - (BE- - BE,E2) = amount of emission remaining after
application of control 2
6. [B - BEj -(BE2 - BE1E2)]E3 = amount of emission reduction using
control 3
7. Total Emissions Reduction
= BEj + (B - BEj)E2 + [B - BEj -(BE2 - BEjE2)]E3
= BEj + BE2 - BEjE2 + BE3 - BEjE3 - BE2E3 + BEjE^
= BEj + BE2 + BE3 - BEjEg - BEjE3 - BE2E3 + K^l
A-3
-------
8. The effective removal efficiency (%F) of controls 1, 2, and 3
acting on baseline emissions is:
EEFF = El + E2 + E3 ' ' ' + (E1E2E3>
The two combined efficiency formulas were used to calculate the efficiency
of various OTVC and in-line cleaner control scenarios listed in Chapter 4 using
the efficiency estimates for individual techniques. Table A-l presents the
range of efficiency for individual control techniques. These efficiency ranges
were based on data in Tables 4-2 through 4-4 and reflect only those tests
showing the effectiveness of control techniques on cleaners with the same
characteristics as baseline conditions. It is assumed that a baseline OTVC has
the following characteristics: (1) 0.75 FBR, (2) 70°F to 80°F primary
condensing temperature for all solvents except MC and CFC, which have
temperatures around 50°F to 60°F and (3) 100 fpm room air speed. A baseline
in-line cleaner is assumed to have a 1.0 FBR. The control efficiencies listed
in Table A-l are intended to represent levels that can reasonably be expected
under normal cleaner operating conditions.
Table A-2 presents the combined control efficiency for the OTVC and
in-line cleaner control scenarios. An example calculation for OTVC control
scenario (11 fpm hoist, freeboard refrigeration device - BF, 1.0 FBR) follows:
Idling Emissions
El + E2 - (E1E2>
0.39 + 0.26 - (0.39 x 0.26) = 55% (lower end of range)
0.39 + 0.58 - (0.39 x 0.58) = 74% (upper end of range)
Working Emissions
El + E2 + E3 - - - +
0.28 + 0.19 + 0.28 - (0.28 x 0.19) - (0.28 x 0.28) - (0.19 x 0.28) +
(0.28 x 0.19 x 0.28) = 58% (lower end of range)
0.28 + 0.21 + 0.52 - (0.28 x 0.21) - (0.28 x 0.52) - (0.21 x 0.52) +
(0.28 x 0.21 x 0.52) = 73% (upper end of range)
A-4
-------
TABLE A-l. EFFECTIVENESS OF SOLVENT CLEANER CONTROL TECHNIQUES
Achievable Emission Reduction Efficiency
Idling Working Downtime
Control Techniques Emissions Emissions Emissions
OTVC
o Hoist 9 11 fpm or less - 28
o 1.0 FBR 39 19-21
o Automated cover - 41-48
o Freeboard refrigeration device
- Above freezing - 16-50
- Below freezing 26 - 58 28-52
o Hoist @ 3 fpm or less - 82
o 1.0 FBR 39 19-21
o Sump cooling device - - 90
o Carbon adsorption - 65 -
o Enclosed design - 42-67
In-Line Cleaners
o Freeboard refrigeration device
- Above freezing 8
- Below freezing 60
o Carbon adsorber 60
o Hot vapor recycle/
Superheated vapor 70
o Sump cooling device - 90
A-5
-------
TABLE A-2. EFFECTIVENESS OF SOLVENT CLEANER CONTROL TECHNIQUE SCENARIOS
r . , T . .
Control Techniques
Idling
Emissions
Control Efficiency
Working
Emissions
Downtime
Emissions
OTVC
o Hoist 9 11 fpm 55
Freeboard refrigeration device (BF)
1.0 FBR
- 74
o Hoist 9 11 fpm
Enclosed design
2.0 FBR sump cooling
o Hoist 9 11 fpm
Automated cover
53-74
41
o Hoist 9 3 fpm 55
Freeboard refrigeration device (BF)
1.0 FBR
o Hoist 9 3 fpm
Enclosed design
1.0 FBR sump cooling
o Hoist 9 3 fpm
Automated cover
In-Line Cleaners
o Freeboard refrigerationd evice (BF)
o Carbon adsorption
o Hot vapor recycle/
Superheated vapor
o Freeboard refrigeration device (BF)
Sump cooling
o Hot vapor recycle/
Superheated vapor
Sump cooling
48
74
53 - 74
41 - 48
58-73
66 - 78
57-62
go
91 . 95
89-91
60
60
70
60
70
90
90
90
A-6
-------
APPENDIX B
OVERALL EFFICIENCY OF
SELECTED CONTROL SCENARIOS
B-l
-------
TABLE B-1. OVERALL EFFICIENCY OF OTVC CONTROL SCENARIOS UNDER SCHEDULE A8
CD
i
ro
Idling X Total Working X Total Downtime % Total
Control b Emissions Emissions Emissions Emissions Emissions Emissions
Scenario Reduction Due to Idling Reduction (X) Due to Working Reduction (X) Due to Downtime
1 55-74 36 58 - 73 33 - 31
2 53 - 74C 36 68 - 78 33 90 31
3 «1 - 48° 36 57 - 62 33 0 31
4 55-74 36 90 33 0 31
5 53 - 74° 36 91 - 95 33 90 31
6 41 - 48C 36 89 - 91 33 0 31
"schedule A assumes: 6 hr/day idling, 2 hr/day working, and 16 hr/day downtime for 5 days/wk. 52 wks/yr-
b 24 hr/day downtime for 2 days/wk, 52 wks/yr. '
Control Scenario 1: Automated parts handling a 11 fpm; Below-freezing FRD; 1.0 FBR
Control Scenario 2: Automated parts handling a 11 fpm; Enclosed Design, Sump Cooling
Control Scenario 3: Automated parts handling a 11 fpm; Automated Bi -parting Cover
Control Scenario 4: Automated parts handling a 3 fpm; Below- freezing FRD- 1.0 FBR
Control Scenario 5: Automated parts handling a 3 fpm; Enclosed Design; Sump Cooling
cControl Scenario 6: Automated parts handling a 3 fpm; Automated Bi -parting Cover
Assumes that control efficiency is at least as good on idling emissions as ,i t is on working emissions (where onlv
working emissions control efficiency data are available).
Overall
Emissions
Reduction (X)
40 - 50
70 - 80
30 - 40
50 - 60
80 - 90
40 - 50
-------
TABLE B-2. OVERALL EFFICIENCY OF OTVC CONTROL SCENARIOS UNDER SCHEDULE 8*
Idling
Control . Emissions
X Total
Emissions
Scenario Reduction Due to Idling
1 55
2 53
3 41
4 55
5 53
6 41
- 74
- 74C
- 48C
- 74
- 74C
- 48C
10
10
10
10
10
10
Working
Emissions
Reduction (X)
58 -
68 -
57 -
90
91 -
89 -
73
78
62
95
91
X Total
Emissions
Due to Working
81
81
81
81
81
81
Downtime
Emissions
Reduction (X)
-
90
0
0
90
0
X Total
Emissions
Due to Downtime
9
9
9
9
9
9
Overal I
Emissions
Reduction (X)
50 - 70
70 - 80
50 - 60
80
90
80
a
Schedule B assumes:
6 hr/day idling, 12 hr/day working, and 8 hr/day downtime for 5 days/wk, 52 wks/yr;
24 hr/day downtime for 2 days/wk, 52 wks/yr.
Automated parts handling 3 11 fpm; Below-freezing FRD; 1.0 FBR
Automated parts handling 3 11 fpm; Enclosed Design, Sump Cooling
Automated parts handling 8 11 fpm; Automated Bi-parting Cover
Automated parts handling 3 3 fpm; Below-freezing FRD; 1.0 FBR
Automated parts handling 9 3 fpm; Enclosed Design; Sump Cooling
Automated parts handling 8 3 fpm; Automated Bi-parting Cover
Assumes that control efficiency is at least as good on idling emissions as it is on working emissions (where only
working emissions control efficiency data are available).
Control Scenario 1:
Control Scenario 2:
Control Scenario 3:
Control Scenario 4:
Control Scenario 5:
Control Scenario 6:
-------
TABLE B-3. OVERALL EFFICIENCY OF IN-LINE CLEANER CONTROL SCENARIOS UNDER SCHEDULE A"
oo
Control .
Scenario
1
2
3
4
5
Working
Emissions
Reduction (X)
60
60
70
60
70
X Total
Emissions
Due to Working
84
84
84
84
84
Downtime
Emissions
Reduction (X)
-
-
-
90
90
X Total
Emissions
Due to Downtime
16
16
16
16
16
Overall
Emissions
Reduction (X)
50
50
60
65
70
Schedule A assumes: 8 hr/day working and 16 hr/day downtime for 5 days/wk, 52 wks/yr;
24 hr/day downtime for 2 days/wk, 52 wks/yr.
Below-freezing FRD
Carbon Adsorption
Hot Vapor Recycle/Superheated Vapor
Below-freezing FRD; Sump Cooling
Control Scenario 1:
Control Scenario 2:
Control Scenario 3:
Control Scenario 4:
Control Scenario 5: Hot Vapor Recycle/Superheated Vapor; Sump Cooling
-------
TABLE B-4. OVERALL EFFICIENCY OF IN-LINE CLEANER CONTROL SCENARIOS UNDER SCHEDULE B*
03
I
O1
Working
Control . Emissions
Scenario Reduction (X)
1
2
3
4
5
^Schedule B assumes:
Control Scenario 1:
Control Scenario 2:
Control Scenario 3:
Control Scenario 4:
Control Scenario 5:
60
60
70
60
70
X Total Downtime X Total
Emissions Emissions Emissions
Due to Working Reduction (X) Due to Downtime
97 - 3
97 - 3
97 - 3
97 90 3
97 90 3
Overall
Emissions
Reduction (X)
60
60
70
60
70
16 hr/day working and 8 hr/day downtime for 365 days/yr.
Below-freezing FRD
Carbon Adsorption
Hot Vapor Recycle/Superheated Vapor
Below-freezing FRD; Sump Cooling
Hot Vapor Recycle/Superheated Vapor; Sump Cooling
-------
APPENDIX C-l
DERIVATION OF CAPITAL COSTS
C-l
-------
APPENDIX C-l - DERIVATION OF CAPITAL COSTS
C-l.l INTRODUCTION
Table C-l provides a summary of the capital costs used in determining
cost effectiveness for open top vapor, and in-line cleaners. The costs shown
in the table represent fourth quarter 1988 costs and have been updated from
the fourth quarter 1986 costs presented in the remainder of this appendix.
When deriving capital costs, straight averages of vendor quotes were examined,
but other considerations also affected cost choices (as discussed in
Section 5.2.3). A detailed discussion of assumptions made in calculating
specific capital costs for each degreaser follows. The sources of this
information are discussed in Chapter 5.
Capital costs were annualized based on an annual percentage rate of 10
percent and the following equipment lifetimes based on vendor questionnaires:
OTVC: 10 years
In-line: 15 years
All controls except carbon adsorbers were assumed to have the same lifetime as
the degreaser. A carbon adsorber has a reported lifetime of 10 years and was
annualized over this life span.
C-l.2 OTVC's
Based on vendor quotations and the criteria detailed in Section 5.2.2 of
the memorandum, the following base costs for OTVC's were selected:
4.5 ft2:
8.6 ft2:
16 ft2:
38 ft2:
$ 7,500
$10,000
$11,500
$16,000
Controls where more than one vendor quote was obtained are listed below, as
well as methodology for selecting each cost.
C-2
-------
TABLE C-l. CAPITAL COSTS (1988$)
Total Installed Capital Costs ($)
Open Top Vapor Cleaners
Verv Small OTVC 4.5 ft2
Automated Parts Handling
Below-freezing FRD
Above-freezing FRD
Bi -parting Cover
1.0 FBR
Carbon adsorber
Enclosed design
Sump Cool ing
Small OTVC 8.5 ft2
Automated Parts Handling
Below- freezing FRD
Above-freezing FRD
Bi -parting Cover
1.0 FBR
Carbon adsorber
Enclosed design
Sump Cool ing
Medium OTVC 16 ft2
Automated Parts Handling
Below- freezing FRD
Above-freezing FRD
Bi -parting Cover
1.0 FBR
Carbon adsorber
Enclosed design
Sump Cooling
Larae OTVC 38 ft2
Automated Parts Handling
Below- freezing FRD
Above -freezing FRD
Bi -parting Cover
1.0 FBR
Carbon adsorber
Enclosed design
Sump Cooling
New
1,500 - 2,000a
4,500
2,000
7,900
500
28,400
3,000
1,500
1,500 - 2,000
7,600
6,000
9,100
500
28,400
5,000
1,500
3,000 - 3,500
8,600
7,400
10,200
600
42,000
10,000
1,500
3,000 - 3,500
12 500
9,300
12,500
1,200
51,000
Retrofit
1,500 - 2,000
5,400
2,500
8,500
500
29,500
3,000
1,500
1,500 - 2,000
9,100
7,300
10,200
500
29,500
5,000
1,500
3,000 - 3,500
10,300
8,800
11,300
600
43,100
10,000
1,500
3,000 - 3,500
14,700
11,100
14,200
1,200
52,100
C-3
-------
TABLE C-l. CAPITAL COSTS (1988$) (Continued)
Total Installed Capital Costs ($)
New Retrofit
In-line Cleaners 38 ft2
Below-freezing FRD 12 500 14,700
Above-freezing FRD 9,300 11,100
Carbon adsorber 61,000 75,000
Drying tunnel 6,000 6,000
Super heated vapor 3,000 3,000
All automated parts handling systems costs include a range. The lower cost
is a push-button hoist capable of moving at a set speed. The higher cost is
a push-button hoist capable of moving at two distinct speeds during the
cycle.
C-4
-------
C-l.2.1 Raising Freeboard Ratio from 0.75 To 1.0
All vendors currently selling OTVC's with a FBR of 0.75 provided cost
estimates for raising the FBR to 1.0. With the exception of Phillips and
Baron-Blakeslee, the costs included the cost to redesign the equipment;
Phillips and Baron-Blakeslee's costs basically included the sheet metal
enclosure. Although there may be some redesign cost, it is incurred only once
and is spread out over all the units sold. Baron-Blakeslee indicated that the
raised freeboard would be a prefabricated unit that would be easy to install.
Since Phillips' costs were rough estimates and Baron-Blakeslee's costs were
based on actual equipment they sell, it was decided that Baron-Blakeslee's
costs were more reliable. The costs including redesign were not included
since the redesign cost should only be incurred once for each model and not
each time the 1.0 freeboard is requested. Below are Baron-Blakeslee's cost
»
estimates.
Retrofit/New Costs
Model Plant Size For Increased FBR (.75 to 1.0)
4.5 ft2 $ 400
8.6 ft2 $ 450
16 ft2 $ 550
38 ft2 $1,100
C-l.2.2 Covers
C-l.2.2.1 Manual/Mechanically-assisted. All vendors include at least a manual
cover on all degreasers. Detrex and Baron-Blakeslee include mechanically
assisted covers on all degreasers. It was assumed that, at baseline, all
OTVC's have manual covers.
C-l.2.2.2 Power Covers. One of the vendors providing power cover costs
(Branson) does not manufacture power covers, nor have they retrofitted another
manufacturers' cover on a regular basis. Their costs were "best guesses" and
C-5
-------
were eliminated from consideration. The following information was also
obtained from vendor correspondence:
• Unique and Phillips' power covers are mylar roll up covers.
Westinghouse's power cover is a rigid steel top with hinges at the
back.
t According to Phillips a steel roll up cover would cost roughly 3
times the mylar cover.
• Baron Blakeslee's power cover is a steel roll up cover.
Baron-Blakeslee's power cover costs are slightly more than 2 times
the mylar equivalent covers for the 0.4m2 and 0.8m2 degreasers.
This estimate supports Phillips' estimate mentioned above.
• None of the above covers are capable of being closed during
degreaser operation. A cover capable of this is a bi-parting
cover.
• Baron Blakeslee estimates that a bi-parting cover would cost about 2
times the cost of a steel roll up cover.
• Detrex estimates that a bi-parting cover would cost 120 to 133% of
their power cover listed.
Cost Estimate Approach
9
t For the 4.5 and 8.6 ft degreasers, 6 times the mylar cover cost and
2 times the Baron-Blakeslee costs were examined. These values
should approximate the costs of bi-parting steel covers based on the
Phillips estimate that a steel rollup cover costs 3 times a mylar
cover, and Baron Blakeslee's estimate that a bi-parting cover costs
C-6
-------
2 times a steel roll up cover. The following values were obtained.
6x 2x
*
Deqreaser Size "Mvlar Equivalent" Baron-Blakeslee
New Retrofit
4.5 ft2 8,800 10,000 7,000
8.6 ft2 8,500 11,200 8,000
2 ?
• For the 1.5m and 3.5m degreasers, the Detrex estimates were also
available (though confidential):
6x 2x
*
Deoreaser Size "Mylar Equivalent" Baron-Blakeslee
New Retrofit
16 ft2 8,600 12,300 12,000
38 ft2 6,700 15,900 15,000
Based on the above information the following costs were selected:
Degreaser Size Rationale:
p
4.5 ft Based on twice the Baron-Blakeslee cost.
There is only one "mylar equivalent"
New - $ 7000 supplier in this range (Unique) and
Ret - $ 7500 Baron-Blakeslee is a much larger vendor.
Although Baron-Blakeslee has no retrofit
cost increase for a power cover, it was
acknowledged that other manufacturers do.
9
8.6 ft These costs were selected based on the
criteria listed in Section 2.0.
New - $ 8,000
Ret - $ 9,000
Baron-Blakeslee's rollup cover is self contained and simply attaches to
degreaser, therefore there is no increase to retrofit. There is no estimate
available as to how this would differ for a bi-parting cover.
C-7
-------
2
16 ft The lower "mylar equivalent" costs (as
opposed to the smaller cleaners) are due
New - $ 9,000 to only Phillips supplying costs for covers
Ret - $10,000 in these size ranges. Selected costs are
based on the cost presented above and
consideration of Detrex's costs.
Engineering judgement was used to adjust
costs to ensure that these sizes do not
cost less than smaller sizes.
38 ft2
New - $11,000
Ret - $12,500
C-l.2.3 Refrigerated Freeboard Chillers
The following above freezing (AF) and below freezing (BF) chiller costs
were eliminated from consideration because the vendors do not manufacture the
units and have not purchased a significant amount from other vendors to
retrofit to their equipment:
Branson - AF & BF
Unique - BF
o
Westinghouse - AF on 16 ft only
The following costs are recommended based on the basic criteria listed in
Section 2.0 of the memorandum.
AF Chiller BF Chiller
Deqreaser Size
4.5 ft2
8.6 ft2
16 ft2
38 ft2
C-8
New
$1,800
5,300
6,500
8,200
Ret
2,200
6,400
7,800
9,800
New
4,000
6,700
7,600
11,000
Ret
4,800
8,000
9,100
13,000
-------
The costs for new chillers were based on vendor quotes. Retrofit costs for
the chillers were not provided by all vendors. The costs that were provided
ranged from no increase over new costs to 100% increases. The larger vendors,
Baron-Blakeslee and Detrex, had lower percent increases. It was decided to
pick a consistent increase of 20 percent for retrofitting all chillers.
C-l.2.4 Carbon Adsorbers
Three of the responding OTVC vendors (Baron-Blakeslee, Detrex, and
Phillips) manufacture carbon adsorbers. These vendors supplied carbon
adsorber costs only for the size OTVC's their company sells. The costs they
provided ranged widely for comparable size OTVC's. Because taking a simple
average of the reported data yielded inconsistencies (i.e., costs for small
OTVC's were higher than for large OTVC's), the cost data from each vendor was
extrapolated over the entire range of OTVC sizes. This adjustment was made to
ensure a logical progression of costs.
Information provided on retrofit costs was very limited. The information
available indicated there is a small increase in cost for retrofitting a
carbon adsorber. The retrofit costs are associated with retrofitting the lip
exhaust. For estimating retrofit costs, $1,000 was added to the new cost for
each model OTVC. The new and retrofit carbon adsorber costs are shown below.
OTVC Size New Cost Retrofit Cost
4.5 ft2, 8.6 ft2 $25,000 $26,000
16 ft2 $37,000 $38,000
38 ft2 $45,000 $46,000
C-l.2.5 Automated Parts Handling Systems
The following quotes were obtained for automated parts handling systems.
It should be noted that hoist costs were dependent on features and not
necessarily the size of the OTVC.
C-9
-------
Resoonder
System Cost m Comments
Baron-Blakeslee
Baron-Blakeslee
Scanex
Scanex
Scanex
Phillips
Phillips
Detrex
Detrex
Unique
Delta Sonics
Delta Sonics
10,000
16,000
4,500 - 5,000
12,000
18,000 - 25,000
10,000
30,000
15,000
25,000
7,500
1,500 - 2,000
3,000 - 3,500
programmable, 50 Ib
programmable, 200 Ib
variable speed, Model E
variable speed and position, Model R
variable speed, acceleration, Model S
programmable, 100 Ib
programmable, 200 Ib
programmable, 12 Ib
programmable, 50 Ib
variable speed, 50 Ib
1 direction, 1 & 2 speed, 30 Ib
1 direction, 1 & 2 speed, 100-200 Ib
Although more elaborate and expensive controls can be used, the cost analysis
should include the minimum, reasonable control that can be used to meet a
requirement. For this reson, Delta Sonics' hoists were assumed to meet the
minimum requirement. The lower costs in the ranges are for a one-directional
hoist capable of moving up and down at a set speed. The higher prices are for
a hoist capable of switching from 11 fpm to 3 fpm when a part enters the vapor
zoen and then back to 11 fpm once the part has come back through the zone.
These hoists would be push button operated.
Costs
OTVC Size
4.5 ft2
16 ft2
Control Strategies
1 - 3
1,500
3,000
Control Strategies
4 - 6
2,000
3,500
C-10
-------
C-1.3 IN-LINE
Three companies provided costs for In-line cleaners (CC) having the
following sizes:
Unique: 13 ft2
Detrex: 14 ft2
Baron-Blakeslee: 24 ft2 (crossrod)
9
Baron-Blakeslee: 72 ft (monorail)
All of the above cleaners were used to calculate costs for the 38 ft model
cleaner. When recommending costs, average values were used as a guide, but
not strictly adhered to. Based on the vendor quotations, a base cost of
$60,000 was selected.
C-l.3.1 Freeboard Refrigeration Devices
The only cost data provided for above freezing (AF) freeboard
refrigeration devices is from Unique Industries. They provided a new cost of
$8,000 and did not report retrofit data. The non-confidential costs provided
by the CC vendors for below freezing (BF) freeboard refrigeration devices
were:
CC Size
13 ft2
24 ft2
72 ft2
New Cost
$12,000
$12,500
$20,000
Based on these cost estimates and the Detrex confidential cost estimate, a
value of 13,000 was selected for the new cost of a BF chiller. For retrofit
costs it was decided that a consistent increase of 20 percent over new device
costs should be used. [This approach was also taken in estimating the
C-ll
-------
retrofit control costs for OTVC's.] The new and retrofit costs are shown
below:
AF
BF
New
8,000
13,000
Retrofit
9,600
15,600
Carbon Adsorbers
Vendor quotes for carbon adsorbers have the following ranges:
New - $40,000 - $100,000
Retrofit - $66,000 - $100,000
The $100,000 quotes are from Unique who has previously stated that they do not
make carbon adsorbers. The following values were selected using Blakeslee's
costs with some adjustment to take information from Detrex into account.
New - 54,000
Retrofit - 66,000
C-12
-------
APPENDIX C-2
DERIVATION OF ANNUAL COSTS
C-13
-------
APPENDIX C
Actual costs incurred by individual plants in the operation of solvent
cleaners will vary. Table C-2 contains operating requirements which are
typical and should provide a reasonable estimate of operating costs. The
values were obtained from vendor questionnaires and follow-up
correspondence. The estimates from the vendors were evaluated based on
similar criteria to those used for the capital costs.
C-14
-------
TABLE C-2. OPERATING PARAMETERS USED IN COST ANALYSIS
Added Cooling
Added Operator Steam Water
Electricity Floor 2 Labor (Ib/lb (gal/100
(hp) Space (ft*) (hrs/shift) pollutant) Ib Steam)
4.5ft2 OTVC
Hoist .24 ...
Below-freezing FRD 1.5 6 .1
Bi-parting cover .5 - - - -
1.0 FBR - - - -
Enclosed design - - ...
Sump cooling .5 - .1 -
16.0ft2 OTVC
Hoist .2 4 - - -
Below-freezing FRD 1.5 10 ,1 - -
Bi-parting cover 1 - -
1.0 FBR 1 10 ,1
Enclosed design - - ...
Sump cooling 1 - .1 .
38.0ft2 In-line
Below-freezing FRD 3 15 .1 - -
Carbon adsorber 6 100 .5 4 12
Drying tunnel - 10 - - -
Super-heated vapor 3 0 .1 -
Sump Cooling 1.5 0 .1
C-15
-------
CALCULATION OF OPERATING COSTS
The following equations were used along with values taken from Tables 5-6
and C-2 to obtain the annual operating costs. It should be noted that
operating labor costs were considered for all control techniques. However,
supervisory and maintenance labor, maintenance material, and overhead were
only included for carbon adsorbers since this is the only control technique
that would require a significant amount of added labor and maintenance.
1. OPERATING LABOR
Labor rates from 1977 were updated to 4th quarter 1986 using the BLS
Producer Price Index. Shifts per year were obtained from model plant
parameters. Manhours per shift were given in Table C-2.
OL = Shifts x Payrate x Hours
Where OL = Operating Labor, ($/yr)
Shifts = Shifts per year
Payrate « $/hr in 1988 dollars
Hours « Hours of labor per shift.
2. SUPERVISOR LABOR (FOR CARBON ADSORBERS ONLY)
Supervisor labor is estimated at 15 percent of operator labor cost
SL - 0.15 x OL
Where SL * Supervisor Labor, ($/yr)
3. MAINTENANCE LABOR
Maintenance labor is based on .5 manhours per shift.
C-16
-------
ML - Shifts x Payrate x Hours
Where ML * Maintenance
(Remainder same nomenclature as Operating Labor)
4. MAINTENANCE MATERIALS (FOR CARBON ADSORBERS ONLY)
Materials necessary for maintenance are estimated as being equivalent to
maintenance labor costs.
MM » ML
Where MM = Maintenance Material Costs, ($/yr)
5. OVERHEAD (FOR CARBON ADSORBERS ONLY)
Overhead is estimated at 60% of Labor Costs and Maintenance Materials.
OH = .6 (OL + ML + SL + MM)
Where OH = Overhead Costs, ($/yr)
6. MISCELLANEOUS OPERATING COSTS
Includes property tax, insurance, and administration costs. Is estimated
at 4 percent of Total Capital Costs.
MOC = 0.04 x (Total Capital Costs)
Where MOC = Miscellaneous Operating Costs
7 UTILITY COSTS
Annual costs for electricity, steam, and cooling water (where applicable)
were calculated according to the following equations:
C-17
-------
Electricity Cost - hp x 0.746 kw/hp x hrs/yr x EP
Where hp - horsepower requirements
EP « electricity price ($/kwh) in 1988 dollars
Steam Cost - SR x POLL x SP
Where SR - steam requirements (per amount pollutant recovered)
POLL » IDS pollutant recovered per year
SP - steam price ($/lb) in 1988 dollars
Cooling
Water Cost - CWR x POLL x CWP
Where CWR = cooling water requirements
(per Ib of recovered pollutant)
POLL » Ib pollutant recovered per year
CWP = cooling water price ($/gal) in 1988 dollars
8. ADDED PLANT SPACE COSTS
The added plant space costs are calculated as shown below and added to
the capital costs of control prior to annualization of the capital costs.
PS - Space x SCost
Where PS - Plant Space, $.
2
Space - Space Requirements, ft of floor area
SCost * Floor Space Cost,
C-18
-------
9. NET ANNUALIZEC COSTS
Net annualized costs Include annualized capita] costs, annual operating
cost and credit for recovered solvent. Capital cost is annualized according
to the following equation.
AC * Total Capital x Capital Recovery Factor
Where Capital Recovery Factor is calculated for 10 percent
discount rate and the following equipment life times:
All cold cleaner controls - 10 years, CFR = .1627
All OTVC controls - 10 years, CFR = .1627
In-line degreaser controls except carbon adsorbers -
15 years, CFR = .1315
Carbon adsorbers on in-line degreasers - 10 years,
CFR = .1627
C-19
-------
SAMPLE CALCULATION (These are in 1986 $)
The Operating Costs required for a carbon adsorber added on a 38 ft2 Open
Top Vapor Cleaner are shown.
1. OPERATOR LABOR
OL * Shifts x Payrate x Hours
= 250 ^^- x 7 98 309'5 — *- x '5 hours
"u year x />yB 194.7 hour x shift
= $l,563.79/yr
2. SUPERVISOR LABOR
SL * 0.15 (1563.79 $/yr) = $234.57/yr
3. MAINTENANCE LABOR
The calculation is the same as with operator labor, but maintenance labor
rates are used.
ML = 250 Shifts x 8 66 309'5 — *- x -5 nours
ML "u year x a'bt) 194.7 hour x shift
= $l,720.77/yr
4. MAINTENANCE MATERIALS
Equal to Maintenance Labor, $l,720.77/yr
C-20
-------
5. OVERHEAD
OH - .6 (1,563.79 + 234.57 + 1,720.77 +1,720.77)
- $3,143.94/yr
6. MISCELLANEOUS OPERATING COSTS
HOC = 0.04 x 51,220 - 2,048.80
7. ANNUALIZED COSTS
Since the carbon adsorber life is ten years, .1627
AC = .1314 x 51,220 = 8,333.49
Calculational methods for electricity, cooling water, and steam are also
shown.
ELECTRICITY: a 6 hp fan is to be used.
6 hp X 1.34102 hp x 150° hrs/yr x *.0713/kwhr
= $478.52/yr
STEAM: From the Gard Manual, it takes 4 pounds of steam to recover 1 pound
of pollutant from the carbon bed. The emission reduction is
estimated to be 10,661 pounds/year (4,836 kg/yr) at 52 percent
control efficiency
* Ibs steam 10,661 Ibs $5.39 _ $22g 85/vp,r
1 Ib pollutant x year x 1,000 Ibs steam ~ >ZZ9-8Vyear
C-21
-------
COOLING WATER: It is reported that it takes 12 gallons per 100 Ibs of steam
(or 12 gallons per 25 pounds pollutant recovered).
12 gallons 10.661 Ibs SO.087 fn ..
x . m $0.44
25 Ibs pollutant year 1,000 gallons
Since it will take 100 square feet to install the adsorber,
Plant Space costs - 100 ft2 x $42 3fliii
244.7
C-22
-------
APPENDIX C-3
COST EFFECTIVENESS CALCULATION TABLES
C-23
-------
06-Apr-89
Snail OTVC (4.5 ft2)-Schedule A (RETROFIT)
I. VPTTIL COSTS, $
Hoist
Below-freezing FRD
Bl-partlng ocver
1.0 B3R
Enclosed Design
Suvp cooling
Additional plant space
TOM. OPTTH. COSTS
II. AWU*. CfERATDC COSTS. Vyr
Annual 1zed total capital costs
Operating labor
Utilities
o Electricity
rlo Miscellaneous operating costs
.^
Control
Strategy 1
1.500
5.400
0
500
0
0
780
8.180
1.331
358
168
327
Control
Strategy 2
1.500
0
0
0
3.000
1.500
223
6.223
1.012
358
200
249
Control
Strategy 3
1,500
0
8,500
0
0
0
223
10,223
1,663
0
21
409
Control
Strategy 4
2,000
5,400
0
500
0
0
780
8,680
1,412
358
188
347
Control
Strategy 5
2.000
o
0
o
3.000
1.500
223
6.723
1.094
358
200
269
Control
Strategy 6
2,000
8,500
223
10.723
1.745
21
429
TOT*. *WMLEED COST, Vyr
III. COST EFFECTWOeSS
EMISSION FGUCnCN. Ib/yr 1,155
RECOVERED SOLVENT CREDIT. Vyr
MC
TCE
TCA
CFC-113
2.204
1,819
2.093
2,306
1,921
2,195
1.444
2.022
2,310
866
1.155
1.444
1,733
2,310
2,599
(299)
(358)
(445)
(468)
(1,040)
(374)
(448)
(556)
(585)
- (1,300)
(524) -
(627) -
(778) -
(819) -
(1,819) -
(598)
(716)
(890)
(936)
(2,079)
(224) -
(269) -
(334) -
(351) -
(780) -
(299)
(358)
(445)
(468)
(1,040)
(374) -
(448) -
(556) -
(585) -
(1,300) -
(449)
(537)
(667)
(702)
(1,560)
(598) - (673)
(716) - (806)
(890) - (1.001)
(936) - (1,053)
(2,079) - (2,339)
1,155
(299)
(358)
(445)
(468)
(1.040)
(374)
(448)
(556)
(585)
(1.300)
ttT JMW.EH) COSTS, Vyr
MC 1,905
PCE 1.8*6
ICE 1,760
TCA 1.737
CfC-113 1.165
1,830
1,757
1.648
1.620
905
1,296
1,193
1,041
1,001
0
-
1,221
1.103
930
884
(260)
1,869 -
1.825
1.760
1.742 -
1,313 -
1.794
1.735
1.648
1.625
1.054
1,932 -
1,858 -
1.750 -
1.721 -
1.006 -
1.857
1.769
1,639
1.604
746
1.322 -
1.205 -
1.031 -
985 -
(159) -
1.248
1.115
920
868
(418)
1.895
1.836
1.750
1,727
1,155
1,821
1,747
1.639
1,610
895
-------
06-^>r-69
Snail OWC (4.5 ft2)-Schedule A (flETTOTr)
Oocitrol
Strategy 1
Control
Strategy 2
Control
Strategy 3
Control
Strategy 4
Control
Strategy 5
Control
Strategy 6
COST EFFECTIVENESS, VI b
»C
PCE
TO
TCA
CFC-113
1.65
1.60
1.52
1.50
1.01
1.27
1.22
1.14
1.12
0.63
0.64
0.59
0.52
0.50
0.00
0.53
0.48
0.40
0.38
(0.11)
2.16
2.11
2.03
2.01
1.52
1.55
1.50
1.43
1.41
0.91
1.34
1.29
1.21
1.19
0.70
1.07
1.02
0.95
0.93
0.43
0.57 -
0.52 -
0.45 -
0.43 -
(0.07) -
0.48
0.43
0.35
0.33
(0.16)
1.64
1.59
1.51
1.49
1.00
1.26
1.21
1.13
1.11
0.62
Control Strategy 1:
Control Strategy 2:
Control Strategy 3:
Cbntrol Strategy 4:
Control Strategy 5:
Cbntrol Strategy 6:
Hoist at 11 fpn, Belowfreeling TO. 1.0 ffiR
Hoist at 11 fpn. Enclosed Dastgn, Sunp Cool Ing
Hoist at 11 fpn, Bl-oarting Over
Hoist at 3 fpn. Below-freezing TO, 1.0 FBR
Hoist at 3 fpn. Enclosed Design. Sunp Cool Ing
Hoist at 3 fpn, Bl-parting Over
i
rsj
en
-------
Snail OTVC (4.5 ft2)-Schedule B (RETROFIT)
C")
1
ro
cr>
I. CAPm. COSTS, I
Hoist
Below-freezing FRD
Bl-parting over
1.0 FW
Enclosed Design
Simp cooling
Additional plant space
TOTAL CAPITAL COSTS
II. AWJAL CFERATDG COSTS. Vyr
Annual Ized total capital costs
Operating labor
Utilities
Electricity
Miscellaneous operating costs
Control
Strategy 1
1,500
5,400
0
500
0
0
780
a, 180
1.331
717
400
327
Control
Strategy 2
1,500
0
0
0
3.000
1,500
223
6.223
1,012
358
170
249
Control
Strategy 3
1,500
0
8,500
0
0
0
223
10,223
1,663
0
177
409
Control
Strategy 4
2,000
5,400
0
500
0
0
780
6,660
1.412
717
400
347
Control
Strategy 5
2,000
0
0
0
3,000
1,500
223
6,723
1,094
358
170
269
Control
Strategy 6
2,000
0
8,500
0
0
0
223
10,723
1,745
0
127
429
TOT* MHWLIZED COST, Vyr
III. COST EFFECTTVB£SS
EHISSICN PEDJCnON, Ib/yr
2,774
3,468 - 4,855
1,789
2.199
2,876
4,855
5,549
3.468
4.162
5,549
5,549
1,891
6,242 - 6.242
2,301
5,549
5,549
RECOVERED S1VENT CREDIT. Vyr
MC (898)
PCE (1,075)
TCE (1,335)
TCA (1,405)
CFO-113 (3,121)
(1.257)
(1,505)
(1.869)
(1,966)
(4.370)
(1.257) -
(1.505) -
(1,869) -
(1,966) -
(4,370) -
(1,437)
(1,720)
(2.136)
(2,247)
(4,994)
(898) -
(1.075) -
(1,335) -
(1.405) -
(3.121) -
(1.078)
(1.290)
(1.602)
(1,685)
(3,746)
(1.437) -
(1,720) -
(2,136) -
(2,247) -
(4,994) -
(1,437)
(1,720)
(2,136)
(2.247)
(4,994)
(1.617)
(1,935)
(2.403)
(2.528)
(5.618)
- (1.617)
- (1.935)
- (2.403)
- (2,528)
- (5,618)
(1.437)
(1,720)
(2,136)
(2.247)
(4.994)
- (1.437)
- (1.720)
- (2,136)
- (2,247)
- (4,994)
tCTANUAL IZED COSTS, Vyr
MC
PCE
TCE
TCA
CFO-113
1.876 -
1.699 -
1,439 -
1,370 -
1347) -
1,517
1,269
905
808
(1,595)
532
284
(80)
(177)
(2,580)
352
69
(347)
(458)
- (3,205)
1,301
1.124
864
795
(922)
-' 1.121
909
597
514
- (1.546)
1,438
1,155
739
628
(2,118)
- 1.438
- 1,155
739
628
- (2.119)
274 -
(45) -
(513) -
(638) -
(3.728) -
274
(45)
(513)
(638)
(3.728)
864
581
164
53
(2.693)
864
581
164
53
- (2,696)
-------
06-Apr-W
9nall OTVC (4.5 ft2>-Sctedule B (RETROFIT)
Control
Strategy 1
Control
Strategy 2
Control
Strategy 3
Control
Strategy 4
Control
Strategy 5
Control
Strategy 6
ODET EFrtCTlVEJCSS, t/lb
« 0.54 -
R£ 0.49 -
TCE 0.41 -
TO 0.39
CTO-113 (0.10) -
0.31
0.26
0.19
0.17
(0.33)
0.11
0.06 -
(0.02) -
(0.04) -
(0.53) -
0.06
0.01
(0.05)
(0.06)
(O.B8)
0.38 -
0.32 -
0.25 -
0.23 -
<0.27> -
0.27
0.22
0.14
0.12
(0.37)
0.26 -
0.21 -
0.13 -
0.11 -
(0.38) -
0.26
0.21
0.13
0.11
(0.38)
0.04
(0.01) -
(0.08) -
(0.10) -
(0.60) -
0.04
(0.01)
(0.08)
(0.10)
(0.60)
0.16 -
0.10 -
0.03 -
0.01 -
(0.49) -
0.16
0.10
0.03
0.01
(0.49)
...
Control Strategy 1:
Control Strategy 2:
Control Strategy 3:
Control Strategy 4:
Control Strategy 5:
Control Strategy 6:
o
i
re
Hoist at 11 fpn. Below-freezing TO, 1.0 FBR
Hoist at 11 fpn. Enclosed Design. Sunp Cooling
Hoist at 11 fpn. Bl-partlng Over
Hoist at 3 fpn, Below-freezing FfO, 1.0 FBR
Hoist at 3 fpn. Enclosed Design. Sunp Cooling
Hoist at 3 fpn, Bl-parttng Cover
-------
Large OTVC (16.0 ft2)-Schedule A (RETROFIT)
o
1
ro
oc
I. CAPITAL COSTS, $
Hoist
Belor-freezlng FAD
Bl-parting over
.0 FBR
Enclosed Design
Surp cooling
Additional plant space
TOTAL CAPITAL COSTS
II. ANitfl creWTDC COSTS, Vyr
Annual Ized total capital costs
Operating labor
Utilities
Electricity
Miscellaneous operating costs
Control
Strategy 1
3,000
10,300
0
600
0
0
1,336
15,236
2,479
358
188
609
Control
Strategy 2
3.000
0
0
0
10,000
1,500
223
14,723
2,395
358
393
589
Control
Strategy 3
3.000
0
11.300
0
0
0
223
14,523
2,363
0
36
581
Control
Strategy 4
3,500
10,300
0
600
0
0
1,336
15.736
2.560
358
188
629
Control
Strategy 5
3,500
0
0
Q
10,000
1,500
223
15,223
2.477
358
393
609
Control
Strategy 6
3,500
0
11,300
0
223
15,023
2,444
0
36
601
TOTAL AWMLEED OOST, Vyr
III. COST EFFEOMieSS
EMISSION REDJCTKH Ib/yr
3,634
4,107 - 5.134
3,736
2.980
3,736
3,837
7.187
8,214
3,080
3.081
4,107
5.134
6.160
8,214
9,240
4,107
5,134
RECOVERED 90.VENT CREDIT, Vyr
PC (1,064)
PCE (1,273)
TCE (1,581)
TO (1,663)
CFC-113 (3,696)
(1,330)
(1,592)
(1,977)
(2,079)
(4.621)
(1,861) -
(2,228) -
(2.767) -
(2.911) -
(6,468) -
(2,127)
(2,546)
(3,162)
(3,327)
(7,392)
(798) -
(955) -
(1,186) -
(1.247) -
(2.772) -
(1.064)
(1,273)
(1,581)
(1,663)
(3.696)
(1,330)
(1,591)
(1,976)
(2,079)
(4,620)
- (1,595)
- (1,910)
- (2,372)
- (2,495)
- (5,544)
(2,127) -
(2,546) -
(3,162) -
(3,327) -
(7,392) -
(2,393)
(2,864)
(3,558)
(3,742)
(8,316)
(1,064)
(1,273)
(1.581)
(1.663)
(3,696)
- (1,330)
- (1,591)
- (1,976)
- (2,079)
- (4,620)
MC
ROE
TCE
TT>
CFC-113
COSTS, Vyr
2,571 -
2.361
2,053 -
1.971
(62) -
2,305
2,043
1,658
1,555
(986)
1.875 -
1.508 -
969 -
825 -
(2.732) -
1,609
1,190
574
410
(3,656)
2.182 -
2.025
1.794
1.733 -
208 -
1.916
1.707
1.399
1.317
(716)
2,406
2,144
1,759
1,657
(885)
- 2,140
1,826
- 1,364
- 1.241
- (1,809)
1,710
1,291
675
511
(3,555)
- 1,444
973
280
95
- (4,479)
2,018
1,808
1,500
1,418
(615)
- 1.752
- 1,490
1.105
- 1.002
- (1,539)
-------
Large OIVC (16.0 ft2)-Sdwdule A (RETROFIT)
Cbntrol
Strategy 1
Control
Strategy 2
Control
Strategy 3
Cbntrol
Strategy 4
Control
Strategy 5
Control
Strategy 6
COST EFTBCnYEMiSS,
MC
PCE
TOE
TCA
CfO-113
Vlb
0.63
0.57
0.50
0.48
(0.02)
0.45
0.40
0.32
0.30
(0.19)
0.26
0.21
0.13
0.11
(0.38)
0.20
0.14
0.07
0.05
(0.45)
0.71
0.66
0.58
0.56
0.07
0.47
0.42
0.34
0.32
(0.17)
0.47
0.42
0.34
0.32
(0.17)
0.35
0.30
0.22
0.20
(0.29)
0.21
0.16
0.08
0.06
(0.43)
0.16
0.11
0.03
0.01
(0.48)
0.49
0.44
0.37
0.35
(0.15)
0.34
0.29
0.22
0.20
(0.30)
Control Strategy 1:
Control Strategy 2:
Control Strategy 3:
Cbntrol Strategy 4:
Control Strategy 5:
Control Strategy 6:
Hoist at 11 fpn. Belon-fneezong TO, 1.0 rBR
Hoist at 11 fpn. Enclosed Design. Sunp Cbol Ing
Hoist at 11 fpn, Bl-parttng Over
Hoist at 3 fpn. Beloyfreezfng FTC, 1.0 rBR
Hoist at 3 fpn. Enclosed Design. Sunp Cbol Ing
rblst at 3 fan, Bl-parting Cover
o
i
ro
-------
06-Apr-89
Large CflVC (16.0 ft2)-Sohedule B (RETROFIT)
Control
Stratagy 1
Control
Strategy 2
Control
Strategy 3
Control
Strategy 4
Control
Strategy 5
Control
Strategy 6
I. CWITA. COSTS, $
Hoist
Below-fneeelng TO
Bf-partlng cxver
1.0 ffiR
Enclosed Design
Suip cooling
Additional plant space
TOTAL C*TWL COSTS
3.000
10.300
0
600
0
0
1.336
15.236
3,000
0
0
0
10.000
1,500
223
14.723
3.000
0
11,300
0
0
0
223
14,523
3,500
10,300
0
600
0
0
1,336
15,736
3,500
0
0
0
10.000
1.500
223
15,223
3,500
0
11,300
0
0
0
223
15,023
i
CO
o
II. »HWL OPERATDG COSTS, Vyr
Annual1zed total capital costs 2,479
Operating labor 717
Utilities
Electricity 400
Miscellaneous operating costs 609
TOM. AWtfLEED COST, Vyr 4,204
2.395
358
303
589
3,645
2,363
0
218
561
3,162
2,560
717
400
629
4,306
2,477
358
303
609
3.747
2,444
0
218
601
3,263
III. COST EFFBCTIVeCSS
MISSION REDUCTION. Ib/yr 12,330
RECOVERED SO.VENT CREDIT, Vyr
MC (3.193)
PCE (3.822)
TO (4.747)
1CA (4,994)
CFC-113 (11.097)
17,262
(4,471)
(5,351)
(6,646)
(6.991)
(15.536)
17.262 - 19.726
(4.471)
(5.351)
(6.646)
(6.991)
(15,536)
(5,110)
(6,116)
(7,595)
(7,990)
(17.755)
12,330
(3,193)
(3,822)
(4.747)
(4.994)
(11,097)
14.796
(3,832)
(4,587)
(5,696)
(5,992)
(13.316)
19.728
(5,110)
(6,116)
(7,595)
(7,990)
(17,755)
19,728
(5,110)
(6.116)
(7,595)
(7,990)
(17,755)
22.194
(5.748)
(6.880)
(8.545)
(8,969)
(19,975)
22,194
(5,748)
(6,880)
(8,545)
(8.989)
(19,975)
19,728
(5,110)
(6,116)
(7,595)
(7,990)
(17,755)
19,728
(5,110)
(6,116)
(7,595)
(7,990)
(17,755)
AWJH.DH) COSTS, Vyr
MC 1,011 - (266) (826) - (1,464) (3?)
PCE 382 - (1,147) (1,706) - (2,470) (661)
TCE (543) - (2,441) (3,001) - (3,950) (1.585)
TEA (789) - (2.787) (3,346) - (4,345) (1.832)
CFC-113 (6.893) - (11.331) (11,891) - (14,110) (7,935)
(670)
(1,425)
(2.535)
(2,831)
(10,155)
(804)
(1.810)
(3.290)
(3.684)
(13.449)
(804)
(1.810)
(3.290)
(3.684)
(13,449)
(2,002)
(3,134)
(4.798)
(5,242)
(16,228)
(2,002)
(3,134)
(4.796)
(5,242)
(16.228)
(1.846)
(2.853)
(4.332)
(4.727)
(14.492)
(1,846)
(2,853)
(4,332)
(4,727)
(14.492)
-------
Large OTVC (16.0 ft2)-Schedule B (RETROFIT)
Cbntrol
Strategy 1
Control
Strategy 2
Cbntrol
Strategy 3
Control
Strategy 4
Control
Strategy 5
Control
Strategy 6
COST EFTECnVB€SS, Vlb
MC 0.08 - (0.02) (0.05) - (0.07) (0.003) - (0.05) (0.04) - (0.04) (0.09) - (0.09) (0.09) - (0.09)
PCE 0.03 - (0.07) (0.10) - (0.13) (0.05) - (0.10) (0.09) - (0.09) (0.14) - (0.14) (0.14) - (0.14)
ICE (0.04) - (0.14) (0.17) - (0.20) (0.13) - (0.17) (0.17) - (0.17) (0.22) - (0.22) (0.22) - (0.22)
TCA (0.06) - (0.16) (0.19) - (0.22) (0.15) - (0.19) (0.19) - (0.19) (0.24) - (0.24) (0.24) - (0.24)
CFC-113 (0.56) - (0.66) (0.69) - (0.72) (0.64) - (0.69) (0.68) - (0.68) (0.73) - (0.73) (0.73) - (0.73)
Cbntrol Strategy 1:
Cbntrol Strategy 2:
Control Strategy 3:
Cbntrol Strategy 4:
Cbntrol Strategy 5:
Cbntrol Strategy 6:
Hoist at 11 fpn. Belov-freezong HO, 1.0 FER
Hoist at 11 fpn, Enclosed Design. Sunp Cbol Ing
Hoist at 11 fpn, Bl-partlng Cbver
Holst at 3 fpn, Belowfrealrq FTC, 1.0 fBR
Hoist at 3 fpn. Enclosed Design, Sunp CbolIng
Hoist at 3 fpn, Bl-partlng Over
i
to
-------
In-1 Ire (38.0 f t2) - Schedule A (RETROFIT)
I. CAPITA. COSTS, $
Below-freezing FRD
Carbon Adsorber
Super Heated Vapor
Sunp Cooling
Additional plant space
TOT*. CAPITA. COSTS
II. AfMJA. OFBWTDG COSTS, J/yr
Annual Ized total capital costs
Operating labor
Supervisory labor
Maintenance labor
Maintenance materials
Utilities
Electricity
Steam
Cool Ing Water
Miscellaneous operating costs
TOTAL AWJAl BED COST, $/yr
III. COST ErTECnVEJtSS
EMISSION REDUCTION, Ib/yr
RECOVERED SOLVENT CREDIT, $/yr
MC
PCE
TCE
TCA
CFC-113
Control
Strategy 1
17,700
0
0
0
835
18,535
2,437
358
363
741
3,900
23,554
(6.100)
(7.302)
(9.068)
(9,539)
(21,199)
Control
Strategy 2
0
74,900
0
0
5,569
80.468
13.092
1.791
269
1.971
1.971
726
563
1
3.219
23,604
23,554
(6.100)
(7.302)
(9.068)
(9,539)
(21.199)
Control
Strategy 3
17,700
0
0
1.500
835
20,035
2.635
717
944
801
5.097
30.620
(7,931)
(9,492)
(11.789)
(12.401)
(27.558)
Control
Strategy 4
0
74.900
0
1.500
5.568
81.968
13.289
2,149
269
1.971
1.971
1.307
732
1
3.279
24.969
30,620
(7,931)
(9,492)
(11.789)
(12.401)
(27.558)
Control
Strategy 5
0
0
3,000
1,500
537
5.037
662
717
944
201
2,525
32,976
(8,541)
(10,223)
(12,696)
(13,355)
(29,678)
Control
Strategy 6
17,700
3,000
o
1,372
22,072
2,902
717
726
883
5,228
32.976
(8.541)
(10,223)
(12.696)
(13.355)
(29.678)
-------
In-line (38.0 ft2) - Schedule A (RETROFIT)
fCT AtU/LCED COSTS, Vyr
MC
PCE
TCE
TCA
CFG-113
COST EFFECnVEICSS. J/lb
1C
PCE
TCE
TCA
CFO113
Corrtrol
Strategy 1
(2.200)
(3.402)
(5.166)
(5.639)
(17.299)
(0.09)
(0.14)
(0.22)
(0.24)
(0.73)
Control
Strategy 2
17.503
16.302
14.535
14.064
2.405
0.74
0.69
0.62
0.60
0.10
Control
Strategy 3
(2.834)
(4.395)
(6.692)
(7.304)
(22,461)
(0.09)
(0.14)
(0.22)
(0.24)
(0.73)
Control
Strategy 4
17,038
15,476
13,180
12,567
(2,589)
0.56
0.51
0.43
0.41
(0.08)
Control
Strategy 5
(6.016)
(7.698)
(10,171)
(10,830)
(27,154)
(0.18)
(0.23)
(0.31)
(0.33)
(0.82)
Control
Strategy 6
(3,312)
(4.994)
(7.467)
(8.127)
(24,450)
(0.10)
(0.15)
(0.23)
(0.25)
(0.74)
o
I
CO
CO
Control Strategy 1: Below-freeing TO
Control Strategy 2: Carton Adsorption
Control Strategy 3: Beloy-Froeelng HO; Su*p Cooling
Control Strategy 4: Carton Mr'irpttan; Sunp Cooling
Control Strategy 5: Super Ht* : Vapor; Sunp Cooling
Control Strategy 6: Beloc-frearing FfD; Super Heated Vapor
-------
In-line (38.0 ft2) - Schedule B (RETROFIT)
I. CAPn/L COSTS, $
Bel o»-f reeling FRO
Carton Adsorber
Super Heated Vapor
Su*p Cooling
Additional plant space
TOTAL CAPITAL COSTS
II. AWJAL OPERATDG COSTS. Vyr
Annual Ized total capital costs
Operating labor
Supervisory labor
Kilrrtenanoe labor
Maintenance materials
V Utll Itles
co Electricity
*" Steam
Cool Ing Hater
Miscellaneous operating costs
TOTAL ANilA-EED GOCT, Vyr
III. COST EFFECTMICSS
EMISSION ROUCnON, Ib/yr
RECOVERED SaVEKT CREDIT. Vyr
>c
FCE
TO
TCA
CFC-113
Control
Strategy 1
17.700
0
0
0
835
18,535
2.437
1.003
1,017
741
5,199
68,366
(17,712)
(21,200)
(26,329)
(27.696)
(61,547)
Control
Strategy 2
0
74,900
0
0
5.568
80,468
13,092
5,016
752
5.518
5,518
2,034
1.636
3
3,219
36,788
68,386
(17.712)
(21.200)
(26.329)
(27.695)
(61.547)
Control
Strategy 3
17.700
0
0
1,500
835
20.035
2.635
1.505
1.272
801
6.213
68,386
(17,712)
(21.200)
(26.329)
(27.696)
(61,547)
Control
Strategy 4
0
74,900
0
1.500
5,568
81,968
13.289
5,517
752
5,518
5,518
2.289
1,636
3
3.279
37,801
i
68,386
(17,712)
(21,200)
(26.329)
(27.696)
(61,547)
Control
Strategy 5
0
0
3.000
1.500
537
5,037
662
1,505
1.272
201
3,641
96,880
(25,092)
(30.033)
(37.299)
(39.236)
(87.192)
Control
Strategy 6
17.700
o
3.000
0
1.372
22.072
2.902
2,006
2,034
863
7.825
96.880
(25,092)
(30.033)
(37,299)
(39.236)
(87,192)
-------
Control
In-line (38.0 ft?) - Schedule B (FCTCFIT) Strategy 1
fCT HHH.UH) COSTS. J/yr
1C
PCE
lit
TCft
CFC-113
COST EFFBCTlVBtSS, $/lb
1C
PCE
TEE
TCA
CFC-113
(12,513)
(16,001)
(21,130)
(22.496)
(56.349)
(0.18)
(0.23)
(0.31)
(0.33)
(0.82)
Control
Strategy 2
19,076
15,586
10.459
9.092
(24,760)
0.28
0.23
0.15
0.13
(0.36)
Control
Strategy 3
(11.499)
(14,987)
(20.116)
(21.483)
(55,334)
(0.17)
(0.22)
(0.29)
(0.31)
(0.81)
Cbntrol
Strategy 4
20,089
16.601
11.473
10.106
(23,746)
0.29
0.?4
0.17
0.15
(0.35)
Control
Strategy 5
(21.451)
(26.392)
(33.658)
(35,596)
(83.551)
(0.22)
(0.27)
(0.35)
(0.37)
(0.86)
Cbntrol
Strategy 6
(17.267)
(22.207)
(29.473)
(31,411)
(79,367)
(0.18)
(0.23)
(0.30)
(0.32)
(0.82)
—
I
CO
en
Control Strategy 1: Bel ov-f race Ing TO
Cbntrol Strata^ 2: Carbon Msorptton
Cbntrol Strategy 3: Below-Freezing HO; Sunp Cooling
Cbntrol Strategy 4: Carbon Adsorption; Surp Cooling
Cbntrol Strategy 5: SM»T Heated Vapor; Surf God Ing
Cbntrol Strategy 6: Below-freezing TO; Super Heated Vapor
-------
06-Apr-89
01VC (4.5 ft2)- Schedule A
I. CAPITAL COSTS, t
Hoist
Belor-freorfng TO
B1-part1ng over
1.0 FBR
Enclosed Design
StMp cooling
Additional plant space
TOTAL CAPITAL COSTS
II. MNJAL OPEWTING COSTS. Vyr
Annual 1zed total capital costs
Operating labor
Utilities
Electricity
Miscellaneous operating costs
Control
Strategy 1
1.500
4.500
0
500
0
0
780
7,280
1,184
358
188
291
Control
Strategy 2
1.500
0
0
0
3000
1.500
223
6,223
1,012
358
200
249
Control
Strategy 3
1.500
0
7,900
0
0
0
223
9,623
1.566
0
21
385
Control
Strategy 4
2,000
4,500
0
500
0
0
783
7,780
1,266
358
188
311
Control
Strategy 5
2,000
0
0
0
3000
1.500
223
6.723
1.094
358
200
269
Control
Strategy 6
2,000
0
7,900
0
0
0
223
10.123
1.647
0
21
405
oo TOTAL AffUALEED COST, l/yr
III. COST EFFECTIVEfeSS
EMISSION REOJCnON, Ib/yr
2,022
1,155 - 1.444
1.819
1,972
2,123
2,022
1.921
2,310
866
1.155
2,073
1,444
1.733
2.310
2.599
1.155
1.444
PEOOVEFED SOLVENT CFEDIT, Vyr
MC (299)
PCE (358)
TCE (445)
1CA (468)
CFC-113 (1.040)
(374)
(448)
(556)
(585)
(1.300)
(524)
(627)
(778)
(819)
(1,819)
(598)
(716)
(890)
(936)
- (2,079)
(224) -
(269) -
(334) -
(351) -
(780) -
(299)
(358)
(445)
(468)
(1,040)
(374) -
(448) -
(556) -
(585) -
(1,300) -
(449)
(537)
(667)
(702)
(1,560)
(598) -
(716) -
(890) -
(936) -
(2,079) -
(673)
(806)
(1,001)
(1,053)
(2.339)
(299)
(358)
(445)
(468)
(1,040)
(374)
(44d)
(556)
(585)
- (1.300)
t€T WHJALEED COSTS, t/yr
1C
PCE
TCE
1CA
CFC-113
1.723
1.664 -
1,577
1.554
982
1,648
1.574
1.466
1,437
722
1.296 -
1.193 -
1.041
1.001 -
0 -
1,221
1.103
930
884
(260)
1,747
1.703
1,638 -
1.621 -
1.192 -
1,672
1,613
1,527
1,504
932
1,749 -
1.676
1.567 -
1.538 -
824
1,674
1,586
1,456
1,422
564
1.322 -
1,205 -
1,031 -
985 -
U59) -
1,248
1.115
920
868
(416)
1,774
1.715
1.628
1,605
1.033
1.699
- 1,625
- 1,517
- 1,488
773
-------
Snail OWC (4.5 ft2>- Schedule A (ten
Control
Strategy 1
Control
Strata^ 2
Control
Strategy 3
Control
Strategy 4
CBntrol
Strategy 5
Control
Strategy 6
OOST EFHCTlVBtSS, VI b
MC 1.49 - 1.14 0.64 - 0.53 2.02 - 1.45 1.21 - 0.97 0.57 - 0.48 1.54 - 1.18
PCE 1.44 - 1.09 0.59 - 0.48 1.97 - 1.40 1.16 - 0.92 0.52 - 0.43 1.48 - 1.13
Ttt 1.37 - 1.02 0.52 - 0.40 1.89 - 1.32 1.09 - 0.84 0.45 - 0.35 1.41 - 1.05
1C* 1.35 - 1.00 0.50 - 0.38 1.87 - 1.30 1.07 - 0.82 0.43 - 0.33 1.39 - 1.03
OFC-113 0.86 - 0.50 0.00 - (0.11) 1.38 - 0.81 0.57 - 0.33 (0.07) - (0.16) 0.89 - 0.54
Control Strategy 1: Hoist at 11 fpn. Below Freezing TO, 1.0 FBR
Control Strategy 2: Hoist at 11 fpn. Enclosed Design, Simp Cooling
Control Strategy 3: Hoist at 11 fpn. Bl-parting Cover
Control Strategy 4: Hoist at 3 fpm. RelcM Freezing TO, 1.0 FBR
Control Strategy 5: Hoist at 3 fpn, Iiclosed Design, Simp Cooling
Control Strategy 6: Hoist at 3 fpn, Bl-parting Cover
o
i
OJ
-------
06-*pr-89
Snail OWC (4.5 ft2)- Sctedule B (COf)
o
I
I. CAPITAL COOTS, J
Hoist
Below-freezing TO
B1-part1ng over
1.0 FW
Enclosed Design
Suip ooollng
Additional plant space
TOTAL CAPITAL COSTS
II. AWJAL OrBMTING COSTS, Vyr
Annual (zed total capital costs
Operating labor
Utilities
Electricity
Miscellaneous operating costs
Control
Strategy 1
1,500
4.500
0
500
0
0
780
7,280
1,164
717
400
291
Control
Strategy 2
1,500
0
0
0
3000
1.500
223
6,223
1.012
356
170
249
Control
Strategy 3
1,500
0
7,900
0
0
0
223
9,623
1,566
0
127
366
Control
Strategy 4
2,000
4,500
0
500
0
0
780
7,780
1,266
717
400
311
Control
Strategy 5
2,000
0
0
3000
1.500
223
6.723
1.094
358
170
269
Control
Strategy 6
2,000
0
7,900
0
0
0
223
10,123
1.647
0
127
405
g TOTAL AWJALEED COST. Vyr
III. COOT EFFECTIVOESS
EMISSICN RECUCnCN. Ib/yr 3,468
RECOVERED saVENT CREDIT, Vyr
MC
FCE
TCE
1CA
CFO-113
2,592
1,789
2,078
2,693
4,855
4.855
1.891
5,549
3.468
4.162
2.179
5.549
5,549
6.242
6.242
5.549
5,549
(898) -
(1,075) -
(1,335) -
(1.405) -
(3,121) -
(1,257)
(1,505)
(1,869)
(1.966)
(4,370)
(1,257) -
(1,505) -
(1,869) -
(1,966) -
(4,370) -
(1,437)
(1,720)
(2,136)
(2,247)
(4,994)
(898)
(1,075)
(1.335)
(1.405)
(3.121)
- (1.078)
- (1,290)
- (1.602)
- (1.685)
- (3,745)
(1.437) -
(1.720) -
(2,136) -
(2,247) -
(4,994) -
(1,437)
(1,720)
(2,136)
(2,247)
(4.994)
(1.617)
(1.935)
(2,403)
(2,528)
(5,618)
- (1.617)
- (1,935)
- (2,403)
- (2,528)
- (5.618)
(1,437) -
(1,720) -
(2,136) -
(2.247) -
(4.994) -
(1.437)
(1,720)
(2,136)
(2,247)
(4,994)
AmiALEED COSTS. Vyr
MC
FCE
TCE
TO
CFC-113
1,694
1,517
1.257
1.187
(529)
- 1,334
- 1.067
723
625
- (1,778)
532
284
(80)
(177)
(2.580)
352
69
(347)
(456)
- (3.205)
1.180
1.003
743
673
(1.043)
1.000
788
475
392
- (1.668)
1.256 -
973 -
557 -
446 -
(2.301) -
1.256
973
557
446
(2,301)
274 -
(45) -
(513) -
(638) -
(3.728) -
274
(45)
(513)
(638)
(3.728)
742
459
43
(68)
(2.815)
742
459
43
(68)
- (2.815)
-------
Snail OTVC (4.5 ft2)- Sdiedule B tt«).
Cbntrol
Strategy 1
Cbntrol
Strategy 2
Control
Strategy 3
Control
Strategy 4
Control
Strategy 5
Control
Strategy 6
COST EFftCTIVOESS, VI b
MC
PCE
TO
1C*
CfC-113
0.49 -
0.44 -
0.36 -
0.34 -
(0.15) -
0.27
0.22
0.15
0.13
(0.37)
0.11 -
0.06 -
(0.02) -
(0.04) -
(0.53) -
0.06
0.01
(0.06)
(0.06)
(0.58)
0.34 -
0.29 -
0.21 -
0.19
(0.30) -
0.24
0.19
0.11
0.09
(0.40)
0.23
0.18
0.10
0.08 -
(0.41) -
0.23
0.18
0.10
0.08
(0.41)
0.04 -
(0.01) -
(0.08) -
(0.10) -
(0.60) -
0.04
(0.01)
(0.08)
(0.10)
(0.60)
0.13
0.08 -
0.01
(0.01) -
(0.51) -
0.13
0.06
0.01
(0.01)
(0.51)
Control Strategy 1:
Control Strategy 2:
Control Strategy 3:
Control Strategy 4:
Control Strategy 5:
Control Strategy 6:
Hoist at 11 fan. Below Freezing TO, 1.0 FBR
Hoist at 11 fpn. Enclosed Design, Sunp Cooling
Hoist at 11 fpn. Bl-partlng Cover
Hoist at 3 fpn. Below Freezing FfO, 1.0 FBR
Hoist at 3 fpn, Enclosed Design, Sunp Cooling
Hoist at 3 fpn. Bl-parttng Cover
o
i
vr
-------
06-Apr-69
Large OTVC (16.0 ft2)- Schedule A
o
i
i. CAPITAL COSTS, i
Hoist
Bel ow-f reel Ing TO
Bl-partlng ewer
l.OffiR
Enclosed Design
Su«p cooling
Additional plant space
TOTAL CAPITAL COSTS
II. AMUAL OPERATING COSTS. Vyr
Annual Ized total coital costs
Operating labor
Utilities
Electr Icily
Miscellaneous operating costs
Control
Strategy 1
3.000
8,600
0
600
0
0
1.336
13,536
2,202
358
188
541
Control
Strategy 2
3.000
0
0
0
10000
1,500
2Z3
14,723
2,395
358
393
589
Control
Strategy 3
3,000
0
10,200
• o
0
0
223
0
13.423
2,184
0
36
537
Control
Strategy 4
3,500
8,600
0
600
0
0
1,33(
14.036
2.284
358
188
561
Control
Strategy 5
3.500
0
0
10000
1,500
223
15,223
2.477
358
393
609
Control
Strategy 6
3,500
0
10.200
0
0
0
223
13,923
2,265
0
36
548
TOTAL AWJAIEED COST, Vyr 3,290
III. COST ErTECnVEheSS
EMISSION RECUCnCN, Ib/yr 4.107 - 5,134
FECOVEFED SOLVENT CFEDIT, Vyr
3,736
2.757
3,391
7.187
3,837
8.214
3,080
2.850
4,107
5,134
6,160
8.214
9.240
4.107
5,134
PCE
TCE
TCA
CFC-113
(1.064) -
(1.273) -
(1,581) -
(1,663) -
(3,696) -
(1,330)
(1,592)
(1,977)
(2,079)
(4,621)
(1.861) -
(2.228) -
(2,767) -
(2.911) -
(6,468) -
(2.177)
(2,546)
(3.162)
(3,327)
(7,392)
(798) -
(955) -
(1.186) -
(1.247) -
(2,772) -
(1,064)
(1,273)
(1.581)
(1,663)
(3,696)
(1,330) -
(1,591) -
(1,976) -
(2,079) -
(4,620) -
(1,595)
(1,910)
(2,372)
(2,495)
(5,544)
(2.127) -
(2.546) -
(3.162) -
(3,327) -
(7,392) -
(2,393)
(2,864)
(3,558)
(3,742)
(8.316)
(1.064) -
(1.273) -
(1,581) -
(1,663) -
(3.696) -
(1,330)
(1.591)
(1,976)
(2,079)
(4,620)
r£T AtMJALIZED COSTS, Vyr
MC
PCE
TCE
TCA
cre-113
2,226
2,017
1,708
1,626
(407)
- 1,960
1,698
- 1.313
- 1,210
- (1,331)
1,875 -
1.508 -
969 -
825 -
(2,732) -
1,609
1,190
574
410
(3,656)
1,959
1.802 -
1.571 -
1,510 -
(15) - •
1,694
1.484
1,176
1,094
(939)
2,061
1.800
1.415
1,312
(1,229)
1,796
- 1,481
- 1,019
896
- (2,153)
1,710
1,291
675
511
O.555 )
1.444
973
280
_ or
- (4,479)
1,786 -
1,576 -
1.268 -
1.186 -
(847) -
1,520
1,258
873
771
(1,771)
-------
Large OTVC (16.0 ft2>- Schedule A HBO
Control
Strategy 1
Control
Strategy 2
Control
Strategy 3
Control
Strategy 4
Control
Strategy 5
Cofrtrol
Strategy 6
OKT EFFECTIVEKESS. J/lb
MC 0.54 -
FCE 0.49 -
ICE 0.42 -
1C* 0.40 -
OFC-113 (0.10) -
0.38
0.33
0.26
0.24
(0.26)
0.26 -
0.21
0.13
0.11 -
(0.38) -
0.20
0.14
0.07
0.05
(0.45)
0.64 -
0.59
0.51 -
0.49 -
(0.00) -
0.41
0.36
0.29
0.27
(0.23)
0.40
0.35 -
0.28 -
0.26 -
(0.24) -
0.29
0.24
0.17
0.15
(0.35)
0.21 -
0.16
0.08 -
0.06
(0.43) -
0.16
0.11
0.03
0.01
(0.48)
0.43
0.38 -
0.31
0.29 -
(0.21) -
0.30
0.25
0.17
0.15
(0.34)
Control Strategy 1:
Control Strategy 2:
Control Strategy 3:
Cbntrol Strategy 4:
Cbntrol Strategy 5:
Cbntrol Strategy 6:
Hoist at 11 fpn, Bel o*~f racing BO, 1.0 TOR
Hoist at 11 fpn, Enclosed Design. Sunp Cbollng
Hoist at 11 fpn, Bl-parttng Cover
Hoist at 3 fpn. Below-frearing HO. 1.0 PER
Hoist at 3 fpn. Enclosed Design, Sunp Cool1ng
Hoist at 3 fpn, Bl-partlng Cover
-------
06-Apr-89
Large OTVC (16.0 ftZ)- Schedule B (NOT)
O
i
I. CAPITAL COSTS, $
Hoist
Below-freezing FTC
Bl-partlng cover
1.0 FER
Enclosed Design
Sup cooling
Additional plant space
TOTAL CAPITAL COSTS
II. AJHJAL OPERATING COSTS, t/yr
Annual (zed total capital costs
Operating labor
Utilities
Electricity
Miscellaneous operating costs
Cbntrol
Strategy 1
3.000
8,600
0
600
0
0
1.336
13.536
2,202
717
400
541
Control
Strategy 2
3,000
0
0
0
10000
1,500
223
14.723
2.395
358
303
589
Control
Strategy 3
3.000
0
10.200
0
0
0
223
0
D.423
2.184
0
218
537
Control
Strategy 4
3.500
8,600
0
600
0
0
1,336
14.036
2,284
717
400
561
Control
Strategy 5
3,500
0
0
10000
1.500
223
15,223
2,477
358
303
609
Cbntrol
Strategy 6
3,500
10,200
0
0
223
13.923
2,265
0
218
557
TOTAL AWJALEED COST, t/yr 3,860
III. COST EFFECTIVENESS
EMISSION FEtUGlCN. Ib/yr 12,330
BFCOVEHED SOLVENT CREDIT, Vyr
MC (3,193)
PCE (2.848)
TO (4,747)
1CA (4,994)
CFC-113 (11.097)
3,646
2,939
17,262
17.262
19.72B
12.330
14,796
3,961
19,728 - 19,728
3,747
3.040
22,194
22,194
19,728
19,728
(4.471)
(5,351)
(6,646)
(6,991)
(15,536)
(4,471) -
(3,988) -
(6.646) -
(6.991) -
(15,536) -
(5.110)
(6,116)
(7,595)
(7,990)
(17,755)
(3.193) -
(2,848) -
(4.747) -
(4.994) -
(11,097) -
(3,832)
(4.587)
(5,696)
(5,992)
(13,316)
(5,110) -
(4,557) -
(7,595) -
(7.990) -
(17,755) -
(5,110)
(6,116)
(7.595)
(7,990)
(17,755)
(5,748)
(5,127)
(8,545)
(8,989)
(19,975)
- (5,748)
- (6,880)
- (8,545)
- (8,939)
- (19,975)
(5.110)
(4,557)
(7,595)
(7,990)
(17,755)
(5,110)
(6.116)
(7,595)
- (7,990)
- (17,755)
HET ANHJA.EED COOTS, t/yr
PCE
TCE
TCA
CFC-113
666
1.012 -
(887) -
(1.134) -
(7.237) -
(611)
(1.491)
(2.786)
(3.131)
(11,676)
(825) -
(342) -
(3.000) -
(3.345) -
(11,890) -
(1.464)
(2.470)
(3,950)
(4.344)
(14,110)
(255) -
91 .-
(1,808) -
(2.055) -
(8.158) -
(893)
(1.648)
(2.758)
(3,054)
(10,378)
(1.148)
(596)
(3,634)
(4.029)
(13.794)
- (1,148)
(2,155)
- (3,634)
(4,029)
- (13.794)
(2,002)
(1.380)
(4,798)
(5,312)
(16,228)
- (2,002)
- (3,134)
- (4,798)
- (5,3«2)
- U6.22B)
(2,069)
(1,517)
(4,555)
(4,950)
(14,715)
- (2,069)
(3,076)
- (4,555)
- (4,950)
- (14,715)
-------
Urge OTVC (16.0 ft2> Schedule B ««)
Qntrol
Strategy 1
Cbntrol
Strategy 2
Cbntrol
Strategy 3
Control
Strategy 4
Control
Strategy 5
Control
Strategy 6
COST trrtt'l IVBtSS, 1/lb
MC O.OB -
KE 0.08
ICE (0.07) -
TCA (0.09) -
CFC-113 (0.59) -
(0.04)
(0.09)
(0.16)
(0.18)
(0.68)
(0.05) -
(0.02) -
(0.17) -
(0.19) -
(0.69) -
(0.07)
(0.13)
(0.20)
(0.22)
(0.72)
(0.02) -
0.01 -
(0.15) -
(0.17) -
(0.66) -
(0.06)
(0.11)
(0.19)
(0.21)
(0.70)
(0.06) -
(0.03) -
(0.18) -
(0.20) -
(0.70) -
(0.06)
(0.11)
(0.18)
(0.20)
(0.70)
(0.09) -
(0.06) -
(0.22) -
(0.24) -
(0.73) -
(0.09)
(0.14)
(0.22)
(0.24)
(0.73)
(0.10) -
(0.08) -
(0.23) -
(0.25) -
(0.75) -
(0.10)
(0.16)
(0.23)
(0.25)
(0.75)
Control Strategy 1: Hoist at 11 fpn, Bel»-frearing TO, 1.0 flBR
Control Strategy 2: Hoist at 11 fpn. Enclosed Design, Snip Cooling
Cbntrol Strategy 3: Hoist at 11 fpn, Bl-partlng Cover
Cbntrol Strategy 4: Hoist at 3 fpn, Bela*-f razing FTC, 1.0 FBR
Control Strategy 5: Hoist at 3 fpn. Enclosed Design, Sunp Cooling
Cbntrol Strategy 6: Hoist at 3 fpn, Bl-partlng Cover
o
i
oo
-------
—
In-line (36.0 ft?) - Schedule A (ten
I. CAPITA. COSTS. J
Belo»-f rear Ing FFD
Carton Adsorber
Super Heated Vapor
Suip Cooling
Additional plant space
TOTAL CAPITAL COSTS
II. AfWJAL OPERATTJG COSTS. Vyr
Annual Ized total capital costs
Operating labor
Supervisory labor
Maintenance labor
Maintenance materials
Utilities
Electricity
Steam
Cool Ing Mater
Miscellaneous operating costs
TOTAL AWJALEED COST. Vyr
III. COST ErTECnVEJCSS
EMISSION REnJCTICN, Ib/yr
FEOWEHED SO. VENT CPEDIT, Vyr
1C
PCE
TCE
TCA
CFC-113
Control
Strategy 1
14,700
0
0
0
835
15,535
2,043
358
363
621
3,386
23,554
(6.100)
(7.302)
(9,068)
(9.539)
(21,199)
Control
Strategy 2
0
61,300
0
0
5,568
66.868
10,879
1,791
269
1,971
1.971
726
563
1
2.675
20,847
23,554
(6.100)
(7,302)
(9.068)
(9.539)
(21.199)
Control
Strategy 3
14,700
0
0
1,500
835
17,035
2,240
717
944
681
4,583
30,620
(7.931)
(9,492)
(11,789)
(12.401)
(27,558)
Control
Strategy 4
0
61,300
0
1.500
5.568
68,366
11,077
2,149
269
1,971
1,971
1,307
732
1
2,735
22,212
i
30,620
(7,931)
(9.492)
(11.789)
(12,401)
(27.558)
Control
Strategy 5
0
0
3,000
1,500
537
5,037
662
717
944
201
2,525
32,976
(8,541)
(10,223)
(12,696)
(13,355)
(29,678)
Control
Strategy 6
14,700
0
3,000
0
1,372
19,072
2,508
717
726
763
4,714
32.976
(8.541)
(10,223)
(12,696)
(13,355)
(29,678)
-------
o
I
In-line (38.0 ft2) - Schedule A (N«)
NET ANHJA.IZED COSTS. Vyr
K:
FCE
TCE
TCA
CFC-113
COST EFFECTIVENESS, Vlb
(C
FCE
TCE
TCA
CFC-113
Cbntrol
Strategy 1
(2,715)
(3.916)
(5.683)
(6,154)
(17,813)
(0.12)
(0.17)
(0.24)
(0.26)
(0.76)
Control
Strategy 2
14,746
13,545
11.779
11.307
(352)
0.63
0.58
0.50
0.48
(0.01)
Cbntrol
Strategy 3
(3,348)
(4,910)
(7,206)
(7,819)
(22.975)
(0.11)
(0.16)
(0.24)
(0.26)
(0.75)
Cbntrol
Strategy 4
14,281
12,720
10,423
9,811
(5,346)
0.47
0.42
0.34
0.32
(0.17)
Control
Strategy 5
(6,016)
(7,698)
(10,171)
(10,830)
(27.154)
(0.18)
(0.23)
(0.31)
(0.33)
(0.82)
Cbntrol
Strategy 6
(3.827)
(5,509)
(7,982)
(8,641)
(24,965)
(0.12)
(0.17)
(0.24)
(0.26)
(0.76)
Cbntrol Strata^ 1: Belor-freeelng TO
Control Strata^ 2: Carbon Adsorption
Control Stratet* 3: Belot-Frostng TO; Su*> Cooling
Control Stratepy 4: Carbon Adsorption; Sup Cooling
Control Strategy S: Si^er Haated Vapor; Su*> Gaoling
Control Strategy 6: Below-freezing FTC; Super Haated Vapor
-------
IrH Ine (38.0 f t2) - Schedule B OOf)
i. arm. COSTS, s
Bel cM-f reccing FTC
Carton Adsorber
Super Heated Vapor
Suiip Cooling
Additional plant space
TOW. CfPUfL COSTS
II. mw. OPEWTDG COSTS. Vyr
Annual Ized total capital costs
Operating labor
Supervisory labor
Maintenance labor
Maintenance materials
o Utll Itles
' Electricity
cr. Steam
Cool Ing Water
Miscellaneous operating costs
TOT* WUA.IZED COST, Vyr
III. COST EFTOTIVENESS
EMISSION REDUCTION, Ib/yr
PECOVEFED SaVENT CFEDIT. Vyr
1C
PCE
IDE
TC*
CFC-1I3
Control
Strategy 1
14.700
0
0
0
635
15.535
2.043
1.003
1,017
621
4.684
68.386
(17,712)
(21.200)
(26.329)
(27.6%)
(61,547)
Control
Strategy 2
0
61,300
0
0
5.566
66*666
10,879
5,016
752
5.518
5.518
2.034
1,636
3
2.675
34.031
68.386
(17,712)
(21.200)
(26.329)
(27,696)
(61,547)
Control
Strategy 3
14.700
0
0
1.500
835
17.035
2,240
1,505
1,272
661
5,699
68,386
(17,712)
(21,200)
(26,329)
(27,696)
(61,547)
Control
Strategy 4
0
61,300
0
1,500
5,568
68.368
11,077
5,517
752
5.518
5.518
2,289
1.636
3
2,735
35,044
68,386
(17,712)
(21,200)
(26,329)
(27,696)
(61,547)
Control
Strategy 5
0
Q
3.000
1,500
537
5,037
662
1.505
1.272
201
3,641
96,880
(25,092)
(30,033)
(37.299)
(39,236)
(87.192)
Control
Strategy 6
14,700
Q
3.000
0
1,372
19,072
2.508
2.006
2.034
763
7,311
96,880
(25.092)
(30.033)
(37,299)
(39,236)
(87,192)
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Itv-1 Ine (38.0 ft2> - Schedule B (N3O
NET HHifLHED COSTS. J/yr
MC
PCE
ICE
1CA
CFC-113
OOST EFFECTIVENESS. 1/lb
1C
PCE
ICE
TCA
CR>-113
Control
Strategy 1
(13.028)
(16.515)
(21,644)
(2.012)
(56.863)
(0.19)
(0.24)
(0.32)
(0.34)
(0.83)
Cbntrol
Strategy 2
16,319
12,831
7.703
6.335
(27.516)
0.24
0.19
0.11
0.09
(0.40)
Control
Strategy 3
(12.013)
(15.501)
(20.630)
(21,998)
(55.849)
(0.18)
(0.3)
(0.30)
(0.32)
(0.82)
Cbntrol
Strategy 4
17.332
13,645
6,716
7,348
(26,5CB)
0.25
0.20
0.13
0.11
(0.39)
Control
Stratear 5
(21,451)
(26,392)
(33,668)
(35.596)
(83.551)
(0.22)
(0.27)
(0.35)
(0.37)
(0.86)
Cbntrol
Strategy 6
(17,781)
(22.722)
(29.988)
(31,925)
(79.881)
(0.18)
(0.23)
(0.31)
(0.33)
(0.82)
Control Strategy 1: Below-freezing PRO
Control Strategy 2: Carbon Adsorption
Cbntrol Strategy 3: Belov-Freazlng TO; Siwp Cooling
Control Strateoy 4: Carbon Adsorption; Suip Cooling
Control Strategy 5: Skfwr Heated Vapor; Sup Cool Ing
Control Strategy 6: Below-freezing TO; Super Heated Vapor
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing}
1. REPORT NO. 2.
EPA-450/3-89-030
4. TITLE AND SUBTITLE
AT fpTn;3 f 1 v^ rtont"rnl Tprhnol OPV Document —
Halogenated Solvent Cleaners
7. AUTHOR(S)
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Radian Corporation
Progress Center
3200 E. Chapel Hill Road
Research Triangle Park, NC 27709
12. SPONSORING AGENCY NAME AND ADDRESS
U.S. Environmental Protection Agency
Emission Standards Division (MD-13)
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
3. RECIPIENT'S ACCESSION NO.
5. REPORT DATE
August 1989
6. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT NO.
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-02-3816
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
EPA Work Assignment Manager: David Beck (919) 541-5421 FTS: 629-5421
16 ABSTRACT
This document contains information on the use and control of halogenated solvents
in solvent cleaning applications. Described are the types of solvent cleaners
manufactured, sources of solvent emissions, methods of controlling solvent emissions,
and the costs associated with installation of control devices.
17. KEY WORDS AND DOCUMENT ANALYSIS
a. DESCRIPTORS b.lDENTIFIE
Solvent Cleaners
Degreasers
Chlorof luorocarbons
Halogenated Solvents
Emission Control
18 DISTRIBUTION STATEMENT 19 SECURIT
Release Unlimited Unclassi
RS/OPEN ENDED TERMS C. COSATI Held/Group
Y CLASS (Tim. Report, 21 NO OF CAGES
fied 216
J20 SECURITY CLASS /Tllispugf 22 PRICE
Unclassified
EPA Form 2220-1 (Rev. 4-77v,
< O U 5 E. D 1 T > O N
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