PB87-234514
Prevention Reference Manual: Ciiemical
Specific. Volume 6. Control of Accidental
Releases of Carbon Tetrachloride (SCAQMD)
(South Coast Air Quality Management District)
Radian Corp., Austin, TX
Prepared for
Environmental Protection Agency
Research Triangle Park, NC
Aug 87
R9BKBBSE
urmi
U.S. Gf CssssiHts
B&Ssaal Tecfe&cd btesaSsa Sarae
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TECHNICAL REPORT DATA
(Pteote read J&uruetwnt on the revene btjore coajplerwg)
\ REPORT NO 2
EPA/600/8-87/034f
3BEW-crrTg 1 rn
4 TITLE AND SUBTITLE
Prevention Reference Manual: Chemical Specific,
Volume 6: Control of Accidental Releases of
Carbon Tetrachloride (SCAQMD)
6 REPORT DATE
August 1987
6. PERFORMING ORGANIZATION CODE
7 AUTHOR! !)
D. S. T avis, G. B, DeWolf, andJ.D. Quass
8. PERFORMING ORGANIZATION REPORT NO
DCN 87-203-024-98-30
9 PERFORMING ORGANIZATION NAME AND ADDRESS
Radian Corporation
8501 Mo-Pac Boulevard
Austin, Texas 78766
\0 PROGRAM ELEMENT NO
11. CONTRACT/GRANT NO
68-02-3889, Task 98
12 SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Air and Energy Engineering Research Laboratory
Research Triangle Park, NC 27711
13 TYPE OF REPORT AND PERIOD COVERED
Task Final; 11/86 - 5/87
14. SPONSORING AGENCY CODE
EPA/600/13
is supplementary notes AEERL project officer is T. Kelly Janes, Mail Drop 62B, 919/
541-2852.
is abstract j^e manual summarizes information that will aid in identifying and control-
ling release hazards specific to the South Coast Air Quality Management District
(SCAQMD) of .southern California. The SCAQMD has been considering a strategy
for reducing the risk of a major accidental air release of toxic chemicals. The stra-
tegy, which will serve as a guide to industry and communities, includes monitoring
activities associated with the storage, handling, and use of certain chemicals. Car-
bon tetrachloride has an immediately dangerous to life and health ('DLH) concentra-
tion of 300 ppm, making it a moderate acute toxic hazard. To reduce the risk assoc-
iated with an accidental release of carbon tetrachloride, the potential causes of re-
leases from processes using carbon tetrachloride in the SCAQMD must be identified.
Such measures include recommendations on: plant design practices; prevention, pro-
tection, and mitigation technologies; and operation and maintenance practices. Con-
ceptual costs of possible prevention, protection, and mitigation measures are esti-
mated.
w - KEY WORDS AND DOCUMENT ANALYSIS
1 DESCRIPTORS
b IDENTIFIERS/OPEN ENDED TERMS
c COSATt Field/Group
Pollution
Carbon Tetrachloride
Emission Maintenance
Accidents Design
Toxicity
Storage
Pollution Control
Stationary Sources
Accidental Releases
13B
07 C
14G
13 L
06T
15E
18 DISTRIBUTION STATEMENT
Release to Public
18 SECURITY CLASS fThu Reporxj
Unclassified
21 NO OF PAGES
95
20 SECURITY CLASS (Thupcge)
Unclassified
22 PRICE
CPA Form 2220-1 (P-7JJ
i
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PB37-234514
EPA/600/8-87/034f
August 1987
PREVENTION REFERENCE MANUAL:
CHEMICAL SPECIFIC
VOLUME 6: CONTROL OF ACCIDENTAL
RELEASES OF CARBON TETRACHLORIDE (SCAQMD)
By:
D.S. Davis
G.B. DeWolf
J.D. Quass
Radian Corporation
Austin. Texas 78766
Contract No. 68-02-3889 «
Work Assignment 98
hPA Project Officer
T. Kelly Janes
Air and Energy Engineering Research Laboratory
Research Triangle Park. North Carolina 27711
AIR AND ENERGY ENGINEERING RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK, NC 27711
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NOTICE
This document has been reviewed in accordance with
U.S. Environmental Protection Agency policy and
approved for publication. Mention of trade names
or commercial products does not constitute endorse-
ment or recommendation for use.
ii
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ABSTRACT
The South Coast Air Quality Management District (SCAQMD1 of southern
California has developed a strategy for reducing the risk of a major acciden-
tal air release of toxic chemicals. The strategy includes monitoring the
storage, handling, and use of certain chemicals and providing guidance to
industry and communities. This manual summarrizes technical information that
will assist in identifying and controlling release hazards specific to the
SCAQMC associated with carbon tetrachloride.
Carbon tetrachloride has an IDL.H (Immediately Dangerous to Life and
Health) concentration of 300 ppm and is a suspected human carcinogen.
Reducing the risk associated with an accidental release of carbon tetra-
chloride involves identifying some of the potential causes of accidental
releases in processes that use carbon tetrachloride in the SCAQMD. In this
manual, examples of potential causes are identified, as are specific measures
that may be taken to reduce the accidental release risk. Such measures
include recommendations on plant design practices, prevention, protection and
mitigation technologies, and operation and maintenance practices. Conceptual
cost estimates of possible prevention, protection, and mitigation measures are
provided.
11 i
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ACKNOWLEDGEMENTS
This manual was prepared under the overall guidance and direction of T.
Kelly Janes, Project Officer, with the active participation of Robert
P. Hangebrauck. William J. Rhodes, and Jane M. Crum, all of U.S. EPA. In
addition, other EPA personnel served as reviewers. Sponsorship and technical
support was also provided by Robert Antonopolis of the South Coast Air Quality
Management District of Southern California, and Michael Stenberg of the U.S.
EPA, Region 9. Radian Corporation principal contributors involved in
preparing the manual were Graham E. Harris (Program Manager). Glenn B. DeWolf
(Project Director). Daniel S. Davis, Nancy S. Gates. Jeffrey D. Quass, Miriam
Stohs, and Sharon L. Wevill. Contributions were also provided by other staff
members. Secretarial support was provided by Roberta J. Brouwer and others.
Special thanks are given to the many other people, both in government and
industry, who served on the Technical Advisory Group and as peer reviewers.
iv
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TABLE OF CONTENTS
Section page
ABSTRACT ii i
ACKNOWLEDGEMENTS iv
FIGURES Vi
TABLES vi i
1 INTRODUCTION 1
1.1 Background 1
1.2 Purpose of This Manual 1
1.3 Uses of Carbon Tetrachloride 2
1.4 Organization of the Manual 3
2 CHEMICAL CHARACTERISTICS 4
2.1 Physical Properties 4
2.2 Chemical Properties and Reactivity 7
2.3 Toxicological and Health Effects 7
3 FACILITY DESCRIPTIONS AND PROCESS HAZARDS 12
3.1 Processing 12
3.1.1 Manufacture of ChlorofJuorocarbons 12
3.1.2 Photochemical Chlorination 15
3.2 Storage and Transfer 17
3.3 Potential Causes of Releases 18
3.3.1 Process Causes 18
3.3.2 Equipment Causes 19
3.3.3 Operational Causes 20
4 HAZARD PREVENTION AND CONTROL 21
4.1 General Considerations 21
4.2 Process Design 22
4.3 Physical Plant Design 24
4.3.1 Equipment 24
4.3.2 Plant Siting and Layout 32
4.3.3 Transfer and Transport Facilities 34
4.4 Protection Technologies 35
4.4.1 Enclosures 35
4.4.2 Vapor Recovery Systems 36
4.4.3 Incineration 37
4.5 Mitigation Technologies 37
4.5.1 Secondary Containment System 38
4.5.2 Flotation Devices and Foams 41
4.6 Operation and Maintenance Practices 42
4.7 Control Effectiveness 43
4.8 Illustrative Cost Estimates for Controls 45
4.8.1 Prevention and Protection Measures 45
4.8.2 Levels of Control 45
4.8.3 Cost Summaries 48
4.8.4 Equipment Specifications and Detailed Costs . 48
4.8.5 Methodology 48
v
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TABLE OF CONTENTS (Continued)
Section Page
5 REFERENCES 79
APPENDIX A - GLOSSARY 82
APPENDIX B - METRIC (SI) CONVERSION FACTORS 87
FIGURES
Number Page
3-1 Conceptual diagram of typical fluorochlorocarbon process . . 13
3-2 Batch photochlorination reactor 16
vi
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TABLES
Number
2-1 Physical Properties of Carbon Tetrachloride
2-2 Exposure Limits for Carbon Tetrachloride
2-3 Observed Human Health Effects of Exposure to Various
Concentrations
4-1 Key Process Design Considerations For Processes Involving
Carbon Tetrachloride 23
4-2 Materials of Construction for Carbon Tetrachloride Service 25
4-3 Examples of Major Prevention and Protection Measures for
Carbon Tetrachloride Releai.es
4-6 Example of Levels of Control for Carbon Tetrachloride
Storage Tanlc
4-7 Example of Levels of Control For Chlorofluorocarbon Reactor
System
4-12 Estimated Typical Capital and Annual Costs Associated With
Level 1 Chlorofluorocarbon Reactor System
4-13 Estimated Typical Capital and Annual Costs Associated With
Level 2 Chlorofluorocarbon Reactor System
Page
5
9
10
44
^ ^ Estimated Typical Costs of Major Prevention and Protection
Measures for Caroon Tetrachloride Releases t ^
4-5 Summary of Cost Estimates of Potential Levels of Control
For Carbon Tetrachloride Storage Tank and Chlorofluorocarbon
Reactor Systems
49
50
52
4-8 Estimated Typical Capital 3rd Annual Costs Associated With
Baseline Carbon Tetrachloride Storage System 54
^ ^ Estimated Typical Capital and Annual Costs Associated With
Level 1 Caroon Tetrachloride Storage System
55
4-10 Estimated Typical Capital and Annual Costs Associated With
Level 2 Carbon Tetrachloride Storage System 56
4-11 Estimated Typical Capital and Annual Costs Associated With
Baseline Chlorofluorocarbon Reactor System 57
58
59
VII
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TABLES (Continued)
Number Pap.e
4-14 Equipment Specifications Associated With Carbon Tetrachlo-
ride Storage System 60
4-15 Haterial and Labor Cones Associated With Baseline Carbon
Tetrachloride Storage System 62
4-16 Material and Labor Costs Associated With Level 1 Carbon
Tetrachloride Storage System 63
4-17 Material and Labor Costs Associated With Level 2 Carbon
Tetrachloride Storage System 64
4-18 Equipment Specifications Associated with Chlcrofluorocarbon
Storage System 65
4-19 Material and Labor Costs Associated With Baseline Chloro-
fluorocarbon Reactor System 67
4-20 Material and Labor Costs Associated With Level 1 Chloro-
fluorocarbon Reactor System 68
4-21 Material and Labor Costs Associated With Level 2 Chloro-
fluorocarbon Reactor System 69
4-22 Format For Total Fixed Capital Cost 71
4-23 Format For Total Annual Cjst 73
4-24 Format For Installation Costs 78
VTM
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SECTION 1
INTRODUCTION
1.1 BACKGROUND
Recognizing the risk associated with accidental releases of air toxics in
southern California, the South CoaBt Air Quality Management District (SCAQMD),
which includes L06 Angeles, Orange, San Bernadino, and Riverside Counties,
conducted a study in 1985 to determine the presence, quantities, and uses of
hazardous chemicals in the SCAQKD. The SCAQMD study resulted in a report,
"South Coast Air Basin Accidental Toxic Air Emissions Study," that outlined an
overall strategy for reducing the potential for a major toxic chemical release
incident.
The strategy includes monitoring industry activities associated with the
storage, handling, and use of certain chemicals; using the beet technical
information available; and guiding industry and communities in minimizing the
potential for accidental releasee and the consequences of any releases that
might occur.
Historically, there do not appear to have been any significant relea6eG
of carbon tetrachloride in the SCAQMD, Major incidents elsewhere involving
carbon tetrachloride have not been common.
1.2 PURPOSE OF THIS MANUAL
This manual compiles technical information on carbon tetrachloride and on
the prevention of accidental releases of carbon tetrachloride. The manual
addresses and summarizes issues relating to release prevention associated with
the storage and handling of carbon tetrachloride and with process operations
involving carbon tetrachloride as it is used in the SCAQMD.
1
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This manual is not a specification manual, and in fact refers the reader
to technical manuals and other sources for core complete information on th<»
topics discussed. Other sources include manufacturers and distributors of
carbon tetrachloride, and technical literature on design, operation, and lose
prevention in facilities handling toxic chemicals.
1.3 USES OF CARBON TETRACHLORIDE
Carbon tetrachloride is commercially manufactured by the chlorination of
carbon disulfide or by the chlorination of hydrocarbons at pyrolytic tempera-
tures. Currently, its primary applications include chlorofluorocarbon produc-
tion. grain fumigation, and use as a reaction medium. In the past it has been
used for metal degreasing. as a dry cleaning agent, and as a fire-extinguisher
agent. However, because of its suspected carcinogenicity, it has been re-
placed by other chlorinated hydrocarbons in some of these applications.
Numerous references in the technical literature describe the manufacture and
uses of carbon tetrachloride. It appears that in the SCAQMD, carbon tetra-
chloride is not manufactured; however, limited 3urvey data indicate that the
predominant uses of carbon tetrachloride in the SCAQMD are (1):
• As a reactent in chlorofluorocarbon manufacture; and
• As a solvent in the chlormpt ion of paraffins.
Other uses for carbon tetrachloride could not be identified froa the available
survey data.
Storage of carbon tetrachloride includes railroad tank cars used for
Etationary storage and bulk storage tanks.
2
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1.4 ORGANIZATION OF THE MANUAL
Following the introductory section, the remainder of the manual presents
technical information on specific hazards and categories of hazards and theii
control as they relate to carbon tetrachloride.
Section 2 discusses physical, chemical, and toxicological properties of
carbon tetrachloride. Section 3 describes the types of facilities that use
carbon tetrachloride in the SCAQMD and process hazards associated with these
facilities. Hazard prevention and control are discussed in Section 4, as are
the costs of example storage and process facilities that reflect different
levels of control through alternative systems. The examples are for illustra-
tion only and do not necessarily represent a satisfactory alternative control
option in all cases. Section 5 contains references. Appendix A is a glossary
of key technical terms that might not be familiar to all users of the manual,
and Appendix B presents selected conversion factors between metric (SI) and
English measurement units.
3
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SECTION 2
CHEMICAL CHARACTERISTICS
This section of the report describes the physical, chemical, and toxico-
logical properties of carbon tetrachloride as they relate to accidental
release hazards.
2.1 PHYSICAL PROPERTIES
Carbon tetrachloride, at room temperature and pressure, is a colorless,
nonflammable liquid with a characteristic nonirritant odor. Some of its
common physical properties are listed in Table 2-1.
Carbon tetrachloride is a relatively nonpolar compound only slightly
soluble in water. It is, however, soluble in alcohol and acetone, and misci-
ble in benzene, chloroform and ether (2). In addition, carbon tetrachloride
is more dense than water and large sp_lle in water may settle before being
totally dispersed, emulsified or volatilized.
Since carbon tetrachloride has a relatively high evaporation rate, spills
and leaks can result in hazardous releases to the environment. In addition,
since the density of carbon tetrachloride vapor is considerably greater than
that of air, it will remain close to the ground and could create a potentially
dangerous situation for workers and surrounding communities.
Because carbon tatrachloride has a large coefficient of expansion,
expanding approximately 5 percent when warmed from 68°F to 140°F, liquid-full
equipment presents a special hazard (2). A liquid-full vessel is a full
vessel that is not vented and that has little or no vapor space present above
the liquid. A liquid-full line is a section of pipe sealed off at both ends
full of carbon tetrachloride, with little or no vapor space. In such cases.
A
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TABLE 2-1. PHYSICAL PROPERTIES OF CARBON TETRACHLORIDE
Reference
CAS Registry Number
Chemical Formula
Molecular Weight
Normal Boiling Pcint
Melting Point
Liquid Specific Gravity (HjO = 1)
Vapor Specific Gravity (air = 1)
Vapor Pressure
Vapor Pressure Equation
log Pv = A - B
T+C
07782-50-5
CC1.
4
153.82
170.1 °F @ 14.7 psia
-9.26 °F
1.595 ® 68 °F
5.32 @ 68 °F
1.74 psia @ 60 °F
where: Pv = vapor pressure, mrnHg
T = temperature, °C
A = 6.87926, a constant
B = 1,212.021, a constant
C = 226.41, a constant
Liquid Viscosity
Solubility in Water
Specific Heat at Constant Pressure
(Liquid)
0.965 centipoise
800 ppm
0.206 Btu/(lb-°F) @ 68 °F
2
2
2
3
3
4
2
3
(Continued}
5
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TABLE 2-1 (Continued)
Reference
Latent Heat of Vaporization 83.8 Btu/lb 2
Liquid Surface Tension 26.77 dynes/cm @ 68 °F 2
Average Coefficient of Thermal 0.00124/°F 2
Expansion, 0-104 °F
Auto;gnition Temperature >1,500 °r 2
Flash Point None 2
Additional properties useful in determining other properties from
physical property correlations:
Critical Temperature 541.8 °F 2
Critical Pressure 45.4 atm 2
3
Critical Density 34.8 lb/ft 2
Energy of Molecular Interaction 3 27 K 5
Effective Molecular Diameter 5.881 Angstroms 5
6
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there is no room for thermal expansion of the liquid and temperature increases
can result in containment failure.
2.2 CHEMICAL PROPERTIES AND REACTIVITY
Carbon tetrachloride is the most toxic of the chloromethanes and is the
moist resistant to oxidation (2). Although it is non-flammable, when carbon
te:rachloride is mixed with excess water and heated to 482 °F, it decomposes
to carbon dioxide and hydrogen chloride (6). Hydrogen chloride formation is
of concern because of the potential for corrosion of equipment and storage
vessels (2). In addition, if the quantity of water is limited, carbon tetra-
chloride in contact with open fire or hot metal surfaces decomposes to produce
highly toxic phosgene gas (2). Recognizing this thermal decomposition is of
greatest importance when using carbon tetrachloride as a fire-extinguishing
ag,ent.
Carbon tetrachlo-ide does not react with gaseous fluorine at ordinary
temperatures; however, when hydrogen fluoride and carbon tetrachloride react
together at a raised temperature and pressure, fluorine can replace one
chlorine atom to produce a chlorofluorocarbon (2).
Dry carbon tetrachloride does not react with vessels and equipment
constructed of iron and nickel. However, it does react slowly with copper and
lead and can react violently with aluminum and its alloys (2). When carbon
tetrachloride is dissolved in or is in contact with water, it will hydrolize
at a slow but finite rate to produce highly corrosive hydrogen chloride. A
small quantity of stabilizer is normally added to the carbon tetrachloride to
prevent its decomposition. According to various literature sources, a numbei
of compounds are effective as stabilizers (2).
2.3 TOXICOLOGICAL AND HEALTH EFFECTS
The toxicoLogical effects of carbon tetrachloride have been well docu-
mented. both through animal studies and from accidental human exposure (7,8).
7
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The IDLH level (Immediately Dangerous to Life and Health) is 300 parts per
million (ppm) for thirty minutes exposure. In general, exposures below the
IDLH level result in no overt symptoms of illness (3). However, increased
concentration levels or exposure times can cause serious and often fatal
injuries. Table 2-2 summarizes some of the relevant exposure limits for
carbon tetrachloride. Table 2-3 summarizes observed hucian health effects of
exposure to various concentrations of cprbon tetrachloride (6).
Inhalation of carbon tetrachloride vapor is a primary hazard (2).
Symptoms of exposure include nausea and vomiting, headache, burning eyes,
throat, drowsiness, abdominal pain, and weakness. Prolonged or repeated
exposure may result in chronic poisoning. In most poisonings, kidney and
liver damage occur, along with respiratory paralysis and circulatory failure,
often resulting in death (3,8). Carbon tetrachloride is also absorbed through
the skin, but at a much slower rate than by inhalation. Prolonged and
repeated exposure may cause dermatitis, cracking of the skin, and danger of
secondary infection (2).
The carcinogenicity of carbon tetrachloride has been well-documented by
both the International Agency for Research on Cancer and the National Cancer
Institute, who identify it as an animal carcinogen (2). It is also a sus-
pected human carcinogen (2).
8
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TABLE 2-2. EXPOSURE LIMITS FOR CARBON TETRACHLORIDE
Exposure
Limit
Concentration
(ppm)
Description
Reference
IDLH
300
The concentration defined as
posing an immediate danger to
life and health (i.e. causes
irreversible toxic effects for
a 30-minute exposure).
PEL
10
A time-weighted 8-hour exposure
to this concentration as set by
the Occupational Safety and
Health Administration (OSHA),
should result in no adverse
effects for the average worker.
lcl<
TC,
Lo
1,000
20
This concentration is the lowest
published lethal concentration
for a human over a 30- minute
exposure.
This concentration is the lowest
published concentration causing
toxic effects (irritation) for a
1-minute exposure.
9
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TABLE 2-3. OBSERVED HUMAN HEALTH EFFECTS OTT EXPOSURE TO VARIOUS
CONCENTRATIONS3
ppm Predicted Effect
10-11 Tolerated for 3 hours without abnormal reaction
49 Tolerated for 70 minutes without abnormal
reaction
76 Tolerated for 2.5-4 hours without abnormal
react ion
158 After 30 minutes, nervousness, nausea, rapid
pulse and respiration
317 After 30 minetes, nausea, later vomiting.
headache, rapid pulse and respiration
1,191 After 10 minutes, headache, nausea, vomiting,
rapid pulse
2,380 After 5 minutes, dizziness, headache,
sleepiness, rapid pulse
3,180 No effect after 2 and 5 minutes
4,770 After 5 minutes, slight somnolence
6,360 After 2 minutes, heaviness, paresthesias, slight
somnolence, after exposure moderate pressure in
head, moderate signs of intoxication
8,745 After 2 minutes, tinnitus, numbness of lips;
after exposure salivation, paresthesias,
vestigo, and slight somnolence
4,540 After 1 minute, paresthesias, numbness of lips,
salivation, weakness, after 1-1/3 minutes,
moderate fainting: after exposure slurred
speech, 3 minutes later tinicus ind after
additional 2 minute euphoria
(Cont inued)
These health effects are sometimes contradictory because they are based on
actual case hiEtones.
10
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TABL.E 2-3 (Continued)
ppm Predicted Effect
10.000-131000 Tolerated for 0.5-1 hour without immediate or
late effects
14,151 Immediate paresthesias, followed by loss of
consciousness, marked i„ itation, tinitus,
euphoria, moderate headache
25.000-32,000 Dangerous with exposure for 0.5-1 hours
50,000 Fatal after exposure for 5-10 minutes
Source: Adapted from Reference 6.
11
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SECTION 3
FACILITY DESCRIPTIONS AND PROCESS HAZARDS
This section briefly describes the uses of carbon tetrachloride in the
SCAQMD and highlights major process hazards related to accidental releases.
Preventive measures associated with these hazards are discussed in Section 4.
3.1 PROCESSING
Survey data indicate that the primary uses for carbon tetrachloride in
the SCAQMD are as a reactant for chlorofluorocarbon manufacture and as a
solvent for batch photochemical chlorination. This subsection summarizes the
major technical features of typical processing and storage facilities found in
the SCAQMD, and discusses accidental release hazards associated with these
facilities.
3.1.1 Manufacture of Chlorofluorocarbons
A major use of carbon tetrachloride in the SCAQMD is in the manufacture
of chlorofluorobcarbons. One commercially important method of production is
the successive replacement of chlorine in chlorinated hydrocarbon feedstocks
(chlorocarbons) by fluorine, using hydrogen fluoride as a source of fluorine.
Figure 3-1 is a block diagram of a typical liquid phase chlorofluorocarbon
manufacturing prccecs.
The liquid-phase reaction system for the manufacture of chlorofluoro-
carbons consists of a heated reaction vessel containing catalyst dissolved in
carbon tetrachloride, and partially fluorinated intermediated recycled to the
reactor from downstream processing. Antimony pentafluoride or a mixture of
antimony trifluoride and chlorine is typically used as catalyst (2,10).
Liquid hydrogen fluoride and carbon tetrachloride are fed to the reactor. The
carbon tetrachloride is first dried to remove any water that may be present to
12
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ANHYDROUS
HCl
BYPRODUCT
ANHYDROUS
Mf
CCL
STEAM
CCJ. RECYCLE
CHLOHINAieO
HC SIORAGb
1ANKS
CRYOGENIC
CC?F?
STORAGE
CAUSTIC ANO
WATER
SCRUBBERS
ENRICHING
COlUL N
MF
STORAGE
DRUMS
COOLER
MF SETTLER
REACTOR
CCijF
OiSliLLAIiON
COLUMN
CCl?f-
OtSTlLLAflON
COLUMN
CRYOGENIC
CHClFj
STORAGE
figure 3-1.
Con"vptujl diagram of typical I luorot hlorocarbon process.
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prevent corrosive hydrofluoric acid from forming in the system. The reactor
typically operates at a temperature and pressure of approximately 176 °F and
100 psig, respectively (10). Although the fluorination reactions are exother-
mic. additional heat is added to the reactor because the reactor also serves
86 a reboiler for an enriching column. Crude product vapors evolved from the
reactor are fed directly to the enriching column. The column is positioned so
that the liquid bottoms flow by gravity as recycle to the reactor.
After being withdrawn from the enriching column, a stream containing
hydrogen chloride, hydrogen fluoride, and the chlorofluorocarbon products is
sent to an acid recovery column, which typically operates at approximately
100 psig (10). Hydrogen chloride is concentrated at the top of the column end
is recovered as a by-product. The bottoms contain the product fluorocarbons
and residual hydrogen fluoride at a temperature of approximately 12? °F (10).
The hydrogen fluoride is removed in a hydrogen fluoride settler and is re-
cycled to the reactor system.
Trace impurities are removed from the fluorocarbon products by scrubbing
with water and a dilute caustic solution. Following the scrubbing operations,
the product stream is dried and fractionated into verious chlorofluorocarbon
products.
Critical areas in the chlorofluorocarbon manufacturing process, excluding
bulk storage and transfer (discussed in Section 3.3), include the following:
• Feed treatment to remove water from the carbon
tetrachloride feed stream;
• Reactor; and
• Carbon tetrachloride recycle stream.
The feed treatment process to remove water is a critical area because
water promotes corrosion. In the presence of moisture, carbon tetrachloride
16
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can decompose to fora highly corrosive hydrogen chloride which rapidly attacks
many materials, including carbon steel. A properly designed system should use
construction materials that take this corrosion potential into account and
allow a certain moisture concentration to be maintained. Deficiencies or
failures in the water removal system could lead to a protracted corrosion
problem, resulting eventually in equipment failure.
An exothermic reactor is used in the chlorofluorocarbon process, but
since it also serves as a reboiler to an enriching column, a reactor cooling
system is not required for heat removal. In fact, additional heat is added.
A potential hazard is overheating and overpressure caused by a malfunction in
the temperature control system.
The carbon tetrachloride recycle stream presents the hazards of vessel,
piping valve, and pump failure from potential corrosion caused by a buildup of
trace quantities of water in the system.
3.1.2 Photochemical Chlorination
Photochemical chlorination is a process using ultraviolet light as the
energy source for carrying out the reaction between chlorine and a hydrocarbon
feedstock. Photochemical reactors can be batch or continuously operated. In
batch operations, the reaction is carried out in a process solvent such as
carbon tetrachloride. Figure 3-2 shows an example of a typical batch reactor.
A batch reactor consists of a large, stirred jacketed vessel with lamps
inserted through the top. The lamps are usuall- blanketed and water cooled.
Critical areas in this process include:
• Cooling of reactor or lamps;
» Agitation of reactants; and
• Seals on the reactor head or stirrer shaft.
1*)
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LIGHTING UNITS
rr~n
CHLORINE «-£
INLET
JACKET
INLET
JACKET
OUTLET
MIXER
PRODUCT
F^pure J-2. Batch photochlorinstion reactor.
16
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From the perspective of a carbon tetrachloride release, a negative
characteristic of the batch photochemical chlorination process is the use of
carbon tetrachloride as a solvent rather than as a reactant. This means that
in the chlorination process the carbon tetrachloride is present in high
concentrations and the possibility of a release is greater than might exist in
a process where it is consumed as a reactant.
A failure of the cooling system or agitation in the batch reactor could
result in local overheating and leod to equipment failure. Finally, a failure
in the reactor head or agitator seals could result in a release of carbon
tetrachloride.
3.2 STORAGE AND TRANSFER
Carbon tetrachloride is stored in three types of storage vessels: fixed
roof tanks, internal floating roof tanks, and pressure vessels (11). Carbon
tetrachloride is also shipped and stored in tank cars and tank trucks.
The primary hazards associated with the storage of carbon tetrachloride
are:
• Inadequate venting systems;
• Overheating; and
• Overfilling.
Atmospheric and low pressure storage vessels present an additional
problem of carbon tetiachloride emissions from tank vents that can contribute
to health and environmental problems if not controlled.
Transfer of carbon tetrachloride to storage is accomplished either by
means of pumps or compressed inert gas pressure. If compressed inert gas is
17
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is used, it is usually dried first to prevent corrosion of the storage and
transfer vessels.
For safety reasons, j-ump transfer is commonly preferred over compressed
gas transfer. The pumps most coanonly used are centrifugal, rotary, positive
displacement or seal-less, depending on the specific situation. In addition*
self-priming pumps are commonly used since they can provide sufficient dis-
charge pressure for transfer to distant or elevated storage areas, thus
avoiding the hazards associated with dry gas priming of the pump.
3.3 POTENTIAL CAUSES OF RELEASES
Carbon tetrachloride can be used safely in appropriate processing and
storage equipment; however, the potential exists for a hazardous release in
any type of plant that handles this material. Possible sources of such a
release ere numerous. Large-scale releases may result from leaks or ruptures
of large storage vessels, including tank cars on site, or from failure of
process machinery such as pumps that maintain a large throughput of carbon
tetrachloride. Smaller releases cay result from ruptured lines, leaking
valves, fittings, flanges, valve packing, or gaskets. Specific potential
release sources within processes dominant in the SCAQMD were identified in the
preceding subsection of this manual.
Failures leading to accidental releases may be broadly classified as due
to process, equipment, or operational problems. Causes of releases discussed
below are intended to be illustrative, not exhaustive.
3.3.1 Process Causes
Process causes are related to the fundamentals of process checiistry,
control, and general operation. Possible process causes of a carbon
tetrachloride release include:
18
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Backflow of chlorofluorocarbon process reactants to a
carbon tetrachloride feed tank;
Inadequate water removal from carbon tetrachloride and
hydrocarbon feedstock feed in the chlorofluorocarbon
process over a long period of time, leading to progressive
corrosion;
Excessive feeds in any part of the system, leading to
overfilling or overpressuring equipment;
Failure of cooling system to chlorination reactor; and
Loss of condenser cooling to distillation units.
Overheating in reactors or distillation units.
Equipment Causes
Excessive stress due to improper ast'jrial selection,
fabrication, construction, or installation;
Failure of vessels at normal operating conditions due to
weakening of equipment from excessive stress, external
loadings, or corrosion.
Mechanical fatigue end shock in any equipment. Mechanical
fatigue could result from age, vibration, or stress
cycling, caused by pressure cycling, for example. Shock
could occur from collisions with moving equipment such as
cranes or other equipment in process or storage areas;
Thermal fatigue and shock in reaction vessels, heat
exchangers, and distillation columns;
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• Brittle fracture in any equipment, but especially in
carbon steel subjected to extensive corrosion. Equipment
constructed of alloys, especially high-strength alloys
selected to reduce the weight of major process equipment,
might be especially sensitive where some corrosion has
occurred, or where severe operating conditions are encoun-
tered;
• Creep failure in high temperature equionent subjected to
extreme operational upsets, especially excess tempera-
tures. This can occur in equipuent subjected to a fire;
• All forms 'if corrosion, both internal and external.
3.3.3 Operational Causes
Operational causes of accidenta. releases are a result of incorrect
procedures or human errors (i.e., not following correct i-rocedures). These
causes include:
• Overfilled storage vessels;
• Improper process system operation;
• Errors in loading and unloading procedures;
• Inadequate mair.tenance in general, but especially of water
renoval unit operations and pressure relief systems and
other preventive and protective systems; and
• Lack of inspection and non-destructive testing of vessels
and piping to detect corrosion weakening.
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SECTION A
HAZARD PREVENTION AND CONTROL
4.1 GENERAL CONSIDERATIONS
The prevention of accidental releases relies on a combination of techno-
logical, adminict rat:ive, and operation practices that apply to the design,
construction, and operation of facilities where carbon tetrachloride is stored
and used. Considerations in these areas can be grouped as follows:
• Process design;
• Physical plant design;
• Operating and maintenance practices; and
• Protective aystena.
Specific factors in each of these areas must be considered that could
lead to a process upset or failure that could directly cause a release of
carbon tetrachloride to the environiaent or result in an equipment failure that
would then cause the release. Equipment and procedures should be examined to
ensure that they are in accordance with applicable codes, standards, and
regulations. In addition, stricter equipment and procedural specifications
should be in place if extra protection against a release is considered appro-
priate.
The following subsections discuss specific considerations regarding
release prevention; more detailed discussions will be found in the manual on
control technologies, part of this canual series.
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4.2 PROCESS DESIGN
Process design involves the fundamental characteristics of processes that
use carbon tetrachloride. Any discussions of how process design may be
involved in accidental chemical releases must include an evaluation of how
deviations from expected process design conditions could initiate a series of
events that result in an accidental release. The primary focus is on how the
process is controlled in terms of the basic process chemistry involved, and on
the variables of flow, pressure, temperature, composition, and level. Addi-
tional considerations may include quantity measuring systems, mixing systems,
fire protection, and process control instrumentation. Modifications that
enhance process integrity would involve changes in the quantities of mater-
ials, process pressure and temperature conditions, the unit operations,
sequence of operations, the process control strategies, and the instrumenta-
tion used.
Table 4-1 shows the relationship hetween specific key process design
considerations and the individual processes described in Section 3 of this
manual. This does not mean that other factors should be ignored, nor does it
mean that proper attention to the key considerations ensures a safe system.
The factors in the table, however, must be properly addressed if a system is
to be safe.
From the perspective of accidental release prevention, it is most
important to prevent moisture from entering the system and to prevent systems
containing carbon tetrachloride from overheating. Overheating is hazardous
because it may lead to overpressure, which weakens process equipment and
increases the potential for leaks to form at joints and valves. Wide
temperature fluctuations also significantly decrease the life-span of many
materials of construction. Careful monitoring of the moisture content is
important to prevent the decomposition of carbon tetrachloride and the forma-
tion of highly corrosive hydrogen chloride.
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TABLE 4-1. KEY PROCESS DESIGN CONSIDERATIONS FOR PROCESSES INVOLVING CARBON
TETRACHLORIDE
Process Design Considerations Process or Unit Operation
Contamination with water
Flow control of carbon tetrachlo-
ride feed
Teciperature sensing and heating
ciedia flow control
Adequate pressure relief
Mixing
Corrosion monitoring
Teciperature monitoring
Level sensing and control
All
All
Chlorofluorocarbon reactors, dis-
tillation colurn condenser?
Storage tanks, reactors, distilla-
tion columns, heat exchangers
Chlorination reactors
All, but especially recycle
circuits
Chlorination reactors, chlorofluoro-
carbon reactors, distillation colunn
reboilers
Storage tanks, reactors
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4.3 PHYSICAL PLANT DESIGN
Physical plant design considerations include equipaent, sizing and lay-
out, and transfer/transport facilities. Vessels, piping and valves, process
machinery. instrumentation, and factors such as the location of systems and
equipment must all be considered. The following subsections cover various
aspects of physical plant design beginning with a discussion of construction
materials.
4.3.1 Equipment
Materials of Construction—
Materials of construction for equipment used in carbon tetrachloride
service must be chosen to minimize the possible decomposition of carbon
tetrachloride. Table -4-2 presents a list of possible materials of construc-
tion for carbon tetrachloride service (12).
The proper selection of construction materials for carbon tetrachloride
service is dictated by temperature and the presence of moisture. In the dry
state, carbon tetrachloride can be stored in contact with many netal surfaces.
However, on contact with water or heating in air, carbon tetrachloride decom-
poses to form highly corrosive hydrogen chloride. The decomposition rate
increases with increasing temperature and contact with some netal surface
(i.e., iron) (2).
Dry carbon tetrachloride does not react with most metals commonly used
for constructing vessels and equipment, although it does react slowly with
copper and lead (Z). Carbon tetrachloride does react, sometimes explosively,
with aluminum and its alloys (2).
In general, nickel and nickel-copper alloys are used at critical points
of processing plants to minimize and control thermal decomposition of carbon
tetrachloride.
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TABLE 4-2. MATERIALS OF CONSTRUCTION FOR CARBON TETRACHLORIDE SERVICE
For Wet For Dry
Material or Dry CCl^ CCI^ Only
Asphaltj.c Resins X
Ceramic X
Copper
Epoxy Resins X
Fiber Reinforced Plastic (FRP) X
Furane Resins X
Glass X
Hastelloy B X
Hastelloy C X
Hastelloy D X
Inconel X
Iron. Cast
Iron, High Silicon X
Lead X
Monel X
Nickel X
Phenolic Resins X
Polyesters X
Polyvinyl Chloride, Unplasticized X
Saran f.
Stainless Steel, Alloy 20 X
Steel, Mild
Zirconiua X
PolyTetraf luoroethyler.c X
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Vessels—
A variety of storage and process vessels are used in carbon tetrachloride
6ervice. Examples include storage drums, atmospheric and low pressure storage
tanks, chemical reactors, separation columns, and heat exchangers. Each type
of vessel has certain specifications under various codes and standards that
should to be adhered to in design and fabrication.
Storage vessels for carbon tetrachloride range in size from 55-gallon
drumE up to multi-con tanks. Three types of tanks are used for carbon tetra-
chloride storage: fixed roof atmospheric tanks, internal floating roof
atmospheric tanks and pressure vessels (11). Because of the relatively large
inventories contained in carbon tetrachloride storage vessels, when consi-
dering accidental releases they represent one of the nost hazardous parts of a
carbon tetrachloride facility.
Specific release prevention considerations for vessels include: over-
pressure protection, vacuum protection, temperature control, and corrosion
prevent ion.
Several methods for preventing overpressurization and underpressurization
ot carbon tetrachloride storage vessels are employed, depending on the type of
vessel. Atmospheric storage tanks are protected from overpressure and under-
pressure by atmospheric vents and/or pressure vacuum valves. These systems
al'ou air to enter or vapor to escape, depending on the situation. In addi-
tion, some tanks are equipped vith internal floating roof6 to allow for
expansion and contraction.
Situations can arise in whven an atmospheric tank is subjected to pres-
sure or vacuum that it cannot withstand. Vent blockage and insufficient vent
capacity are the two oost common causes of atmospheric tank failure (13). A
coarse wire mesh guard is usually provided over tank vent openings to prevent
objects froa entering the vent and plugging the line somewhere downstream.
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However, the wire mesh guard can become plugged with an accunulation of debris
(13).
Pressure weasels, including storage tankc. tank trucks, and rail cars are
usually protected by pressure relief valves and/or rupture disks. The pres-
sure relief valve is set to relieve slightly above the design working pressure
of the vessel, but well below the maximum allowable working pressure. Al-
though carbon tetrachloride is stored in low-pressure storage vessels, vessels
designed to withstand internal pressures in the range of 0.5-15 psi^. pressure
relief valves are still needed to prevent possible rupture fron overpressure.
Pressure relief valves and rupture discs are designed to prevent explo-
sion by controlled release of overpressurized concents. These relief systems
are usually sized for flashing liquid caused by:
• Fire exposure;
• Thermal expansion;
• Internal reaction/decomposition; and
o Excess supply rates.
Relief piping must be sized for adequate flow. To avoid direct discharge to
the environment, an overflow tank might be provided for overpressurized
liquid. If the possibility exists thac overpressurizing may be caused by
something besides liquid thermal expansion, or where there is no overflow
receiver, the vessels should be relieved to either a Doint in the process
that can handle the discharge flow, or to a vapor recovery system.
General considerations for preventing an accidental release from a
storage vessel also apply to the design and use of process and reaction
vessels. In the latter type of vessels, however, there is a greater degree of
risk, since these containers are often exposed to more severe conditions of
temperature and/or pressure than is a regular storage vessel.
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Primary considerations for process an-* 'eaction vessels include:
• Materials of construction;
• Pressure relief devices;
• Temperature control;
• Overflow protection;
• Foundations and supports.
The chlorination and chlorofluorocarbon reactors represent possible
sources of major releases since they contain a large portion of the carbon
tetrachloride used in their respective processes. These reactors must,
therefore, be constructed of appropriate materials.
The feed to the reactors must be dry since moisture accelerates the
corrosion rate of materials used in construction (e.g., carbon steel) (10).
Provisions should be mad? for excluding moisture during any process shutdowns,
or for purging the reactors at shutdown and before startups.
Piping—
As with carbon tetrachloride vessels, carbon tetrachloride pipework
design must reflect t':*e pressure, temperature, and corrosion concerns associ-
ated with use of the chenical. Careful attention must be paid to pipework and
associated fittings since failures of this type of equipment are major con-
tributors to accidental releases of chemicals. As with other hazardous
chemicals, there are general guidelines for carbon tetracnloride piping
systems. The first is simplicity of design; the number of joints and connec-
tions should be minimized. In addition to being securely supported, pipes
should be sloped, with drainage at the low points. Piping should be con-
structed so as to allow for thermal expansion and should be protected from
exposure to fire and high temperatures. Placement of valves should ensure
isolation of leaking pipes and equipment.
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The correct design and use of pipe supports is essential to reduce
overstress and vibration that could lead to piping failure. The supports
should be designed to handle the load associated with the pipe, operating and
testing medium, insulation, and other equipment. Factors that must be con-
sidered include thermal expansion and contraction, vibrations caused by
pumping and fluid flow, bending moments resultiwg from overpressure in the
pipe, and external loads such as wind or ice accumulation.
All piping should be situated away from fire and fire hazards since tne
decomposition products could trigger an explosion. Piping carrying carbon
tetrachloride should not be routed near other processes or piping networks
that might present an external threat (e.g., piping carrying highly corrosive
materials, high pressure processes). In addition, pipework should be protect-
ed from possible impact and other structural damage.
All types of valves are used in carbon tetrachloride service, including
gate, globe, ball, relief, and check configure*.ions. They must be constructed
of material that does not promote the decomposition of carbon tetrachloride.
Process Machinery—
Process machinery refers to rotating or reciprocating equipment '.hat may
be used in the transfer or processing of carbon tetrachloride. This includes
pumps and compressors used to move liquid or gaseous carbon tetracnloride
where gas pressure padding is insufficient or inappropriate.
Pumps—Many of the concerns for carbon tetrachloride piping and valves
also apply to pumps. To ensure that a given pump is suitable for a carbon
tetrachloride service application, the system designer should obtain informa-
tion from the pump manufacturer certifying that the pump will perform properly
in this applicatior.
Pumps should be constructed of materials that do not promote carbon
tetrachloride decomposition at operating temperatures and pressures. They
should be installed dry and oil-free. The pump's supply tank should have
high- and low-level alarms; tne pump should be interlocked to shut off at low
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supply level or low discharge pressure. External pumps should be situated
inside a diked ares and should be accessible in the event of a tank leak.
In some situations, the potential for seal leakage rules out thi use of
rotating seals. Pump types that either isolate the seals from the piocecs
stream, or eliminate then altogether include canned-motor pumps, vertical
extended-spindle subaersible pumps, magnetically coupled pumps and diaphragm
pumpB (12).
Canned motor pumps are centrifugal units in which the motor housing is
interconnected with the puop casing. Here, the process liquid actually serves
as the bearing lubricant. An alternative concept is the vertical puop often
used on storage tanks. These pumps consist of a submerged impeller housing
connected by an extended drive shaft to the motor. The advantages of this
arrangement arc that the shaft seal is above the maximum liquid level (and is
therefore not wetted by the pumped liquid) and the puop is self priming
because the liquid is above the impeller,
Pumps using stuffing boxes and packing should be provided with double-
packed seal chambers which can be purged with an appropriate inert fluid ouch
as dry and oil-free nitrogen, or with a suitable seal liquid. The seal gas
pressure should exceed the tai.* pressure by an appropriate margin. A seal
fluid back-up system should be considered.
Magnetically-coupled pumps replace the drive shaft with a rotating mag-
netic field as the pump-motor coupling device. Diaphragm pumps are positive
displacement units in which a reciprocating f'exible diaphragm drives the
fluid. This arrangement eliminates exposure of packing and seals to the
pumped liquid. Because of the probability of evertual diaphragm failure,
diaphragm purjps should be carefully considered in view of this hazard
potential.
Improper operation of pumps as a result of cavitation, running dry. and
deadheading can c>-use damage and failure of pumps. If cavitation is allowed
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to occur, pitting and eventual serious damage to the impeller can tesult.
Running a pump dry as a result of loss of head in a feed tank, for example,
can seriously damage a pump. Finally, pumping against a closed valve can have
serious ramifications. A pump bypass or kick-back are useful in avoiding such
an occurrence. Failure of a puap, for whatever reason, can eventually lead to
a hazardous release.
Centrifugal pumps often have a recycle loop back to the feed container
that prevents overheating if the pump is deadheaded. Deadheading is also a
concern with positive displacement pumps. To prevent rupture, positive
displacecent pumps commonly have a pressure relief valve that bypasses to the
pump's suction.
Compressors—Reciprocating, centrifugal, liquid-ring rotary, and non-
lubricated screw compressors are used with carbon tetrachloride. Details of
such compressors are discussed in the technical literature (12).
Like pumps, compressors have the potential for heat buildup and shaft
seal leakage. Heat sources in a compressor include the heat of compression as
well as the heat generated through mechanical friction. Most multistaged
compressors can be equipped with intercoolers that limit heat buildup and
increase compressor efficiency by reducing the volume of gas going to the next
compression stage. Both air and water cooling are used, but water systems
must be designed to prevent leakage and contact of water with carbon tetra-
chloride.
While it is often possible to avoid using rotary shaft seals with carbon
tetrachloride pumps, compressors in carbon tetrachloride service usually
require seals such as double labyrinth seals. These seals have a series of
interlocking tcugh points which, by creating many incremental pressure drops,
reduce total leakage. Also, to further reduce leakage, dry air is injected
into the seal. In the event of deadheading, a compressor discharge can have a
pressure ~e!ief mechanism that vents to the compressor inlet, vapor recovery
system, or incinerator. The inlet vent system appears to be satisfactory for
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a short tern downstream flow interruption. Where a sustained interruption
eight occur, relief to a recovery system or to an incinerator would be safer.
Positive displacement compressors and pumps must always be equipped with
overpressure relief as close to the discharge as possible (non-isolatable).
A.3.2 Plant Siting and Layout
The siting and layout of a pprtieular facility using carbon tetrachloride
is a complex issue requiring careful consideration of numerous factors,
including; other processes in the area, the proximity of population centers,
prevailing winds, local terrain, and potential natural external effects such
ab flooding. The rest of this subsection describes general principles that
night apply to the s .ting and layout of carbon tetrachloride facilities.
Facilities or individual equipment items should be situated to reduce
personnel exposure, both plan*. and public, in the event of a release. Since
there are also other siting considerations, there may be trade-offs between
this requirement and others in a process, some directly safety related.
Siting should provide ready ingress or egress in the event of ar emergency and
yet take advantage of barriers, either man made or natural that could reduce
the hazards of releases. Large distances between large inventories and
sensitive receptors is desirable.
Layout refers to the placement and arrangement of equipment in the
process facility. Various techniques available for formally assessing plant
layout should be considered when planning h-.gh hazard facilities (13).
Following are general layout considerations:
• Large inventories of carbon tetrachloride should be kept away
from sources of fire or explosion hazard.
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• Vehicular traffic should not go too neur carbon tetrachloride
process or storage areas if this can be avoided.
• Where traffic is necessary, precautions should be taken to
reduce the chances for vehicular collisions with equipment,
especially pipe racks carrying carbon tetrachloride across or
next to roadways.
• Carbon tetrachloride piping preferably should not be located
adjacent to other piping that is under pressure or tempera-
ture, or that carries flammable materials.
• Storage facilities should be segregated from the main process
unless the hazards of pipe transport are felt to outweigh the
hazard of the storage tank for site-specific cases.
Because heat increases the decomposition of carbon tetrachloride and
causes thermal expansion of liquid carbon tetrachloride, measures should be
taken to situate piping, storage vessels, and other carbon tetrachloride
equipment so that they are protected from heat sources. Hot process piping,
equipment, steam lines, and other sources of direct or radiant heat should be
avoided. Storage should also be situated away from control rooms, offices,
utilities, storage and laboratory areas. Special precautions should be taken
to keep carbon tetrachloride storage vessels away from potential fire or
explosion sources.
In the event of an emergency, there should be multiple means of access to
the facility for emergency vehicles and crews. Storage vessel shut off valves
should be readily accessible. Containment for liquid storage tanks can be
provided by diking. Dikes reduce evaporation while containing the liquid. It
is also possible to equip a diked area to allow drainage to an underground
containment sump, which would be vented to a vapor recovery system lor safe
discharge. A full containment system using a specially constructed building
vented to a vapor recovery system is another possible option. This type of
33
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secondary containment could be considered for large volume carbon tetrachlo-
ride tanks.
A.3.3 Transfer and Transport Facilities
Transfer and transport facilities where both road and rail tankers are
loaded or unloaded are likely accident areas because of vehicle movement and
the intermittent nature of the operations. Therefore, special attention
should be given to the design of these facilities.
As mentioned in the previous section, tank car and tank truck facilities
should be located away from sources of heat. fire, and explosion. Equipment
in these ereas should also be protected from impact by vehicles and other
moving equipment. These tank vehicles sho.ild be securely moored during
transfer operations; an interlock barrier system is commonly used. Sufficient
space should be available to avoid congestion of vehicles or personnel during
loading and unloading operations. Vehicles, especially trucks, should be able
to move into a.->d out of the area without reversing. High curbs around trans-
fer areas and bairiers around equipment should be provided to protect equip-
ment from vehicle collisions.
When possible, carbon tetrachloride should be transferred via fixed rigid
piping. In situations requiring flexible hoses or tubes, precouticns must be
taken to ensure sound connections. Flexible hoses must be constructed of
materials resistant to carbon tetrachloride and must be designed to withstand
the highest anticipated operating pressures. Avoiding cross contami,- cion of
chemical materials is also a concern. In addition, submerged transfer, the
introduction of carbon tetrachloride into a vessel with the trancfer line
outlet below the liquid surface is used to minimize evaporation and release of
carbon tetrachloride vapors. Vapor balance systems consisting of a pipeline
between the vapor spaces of an unloading vessel and a carbon tetrachloride
storage tank are commonly used to create an essentially closed system to
minimize releases of carbon tetrachloride vapor.
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A.A PROTECTION TECHNOLOGIES
This subsection describes three types of protection technologies for
containment and neutralization:
• Enclosures;
« Vapor recovery systems; and
• Incinerators.
A.A.I Enclosures
Enclosures refer to containment structures that capture any carbon
tetrachloride spilled or vented from storage or process equipment, thereby
preventing immediate discharge of the chemical to the environment. The
enclosures contain the spilled liquid or vapor until it can be transferred to
other containment and discharged at a controlled race that would not be
injurious to people or to the environment, or transferred at a controlled rate
to a vapor recovery or incineration system.
Specially designed enclosures for carbon tetrachloride storage or process
equipment do not appear to De widely used. The idea that it may be preferable
to locate toxic operations in the open air has been mentioned in the
literature (133. as has the opposing idea that sometimes enclosures may be
appropriate. The desirability of enclosure depends partly on the frequency
with which personnel must be involved «nth the equipment. A cormon design
rationale for not having an enclosure --here toxic sateri.3ls are used is to
prevent the accumulation of toxic concentrations within enclosed areai-
Howevsr, if the issue is providing secondary containment, total enclosure nay
be appropriate. Enclosures should be equipped with continuous monitoring
equipment and alarms. Alarms should sound wnenaver lerhal or fiammable
concentrations are detected.
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Care must be taken when an enclosure is built around pressurized equip-
ment. It would not be practical to design an enclosure to withstand the
pressures associated with a sudden release of a pressurized vessel. An
enclosure would probably fail because of the pressure created from such a
release and could create an additional hazard. In these situations, it may be
determined that an enclosure is not appropriate. If an enclosure is built
around pressurized equipment, then it should be equipped with some type of
explosion protection, such as rupture plates designed to fail before the
entire structure fails.
The type cf structures that appear suitable for carbon tetrachloride are
concrete blocks, or concrete sheet buildings, or bunkers. An enclosure would
have a ventilation system designed to draw in air when the building is vented
to a vapor recovery or incineration system. The bottom section of the build-
ing used for stationary storage containers should be liquid tight to retain
any carbon tetrachloride that might be spilled. Buildings around rail cars
used for storage do not normally lend themselves easily to effective liquid
containment. However, containment can be accomplished if the floor of the
building is excavated several feet below the track level, while the tru^lcs are
supported at grade in the center.
While enclosures for secondary containment of carbon tetrachloride spills
or release are not widely used, they can be considered for areas near sensi-
tive receptors.
4.4.2 Vapor Recovery Systems
Vapor recovery is a method of recovering toxic materials from process
streams. Common systems used are vapor-liquid absorption, compression,
refrigeration, or vapor-solid absorption (14). These systems can control
carbon tetrachloride releases from vents and pressure relief discharges, from
process equipment, or from secondary containment enclosures.
Carbon tetrachloride discharges are commonly sent to a refrigerated vapor
recovery unit or to a carbon absorption unit. If such a system is used to
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protect against emergency releases, how it would be activated in time to
respond tc an emergency load must be considered. One approach used in some
process facilities is to maintain the recovery unit in continuous operation.
For many facilities, this would not be practical, and the system might be tied
into a trip system to turn it on when it is needed.
4.4.3 Incineration
Incineration is a traditional method of destroying toxic vapor from
process screams. Such devices can be used for controlling carbon tetrachlo-
ride releases from vents and pressure relief discharges, from process equip-
ment, or from secondary containment enclosures.
Carbon tetrachloride discharges could be mixed with fuel and air m a
thermal oxidation unit to convert the toxic vapor to hydrogen chloride. An
additional problem arises in that hydrogen chloride is highly corrosive and
thus the incineration system would have to be constructed of corrosion-
resistant materials. Also, an acid-gas scrubber is needed to remove the
hydrogen chloride from the vent gases before being released.
Considerations for activation in the event of an emergency load of
hazardous vapor are the same as those associated with vapor recovery systems
discussed above.
4.5 MITIGATION TECHNOLOGIES
If, in spite of all precautions, »\ large release of carbon tetrachloride
occars, the first priority is to rescue- workers in the immediate vicinity of
the accident and evacuate persons from downwind areas. The source of the
release should be determined, and the leak should be plugged to stop the flow,
if possible. The next primary concern becomes reducing the effects of the
release on the plant and the surrounding community. Reducing the consequences
of an accidental release of a hazardous chemical is referred to as mitigation.
Mitigation technologies include such measures as physical barriers, water
sprays and fogs, and foams, where applicable. The purpose of a mitigation
37
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technique is to divert, limit, or disperse the chemical that has been spilled
or released to the atmosphere to reduce the atmospheric concentration and the
area affected by the chemical. In addition, secondary containment systPns
such as impounding basins, dikes, and flotation devices and/or foaos are used
to reduce the rate of evaporation from a spilled liquid. The mitigation
technology chosen for a particular chemical depends on the specific properties
of the chemical, including its flamoability, toxicity, reactivity, and those
properties that determine its dispersion characteristics in the atmosphere.
^.5.1 Secondary Containment System
Specific types of secondary containment systems include excavated basins,
natural basins, earth, steel, or concrete dikes, and high impounding walls.
The type of containment system best suited for a particular storage tank or
process unit depends on the risk associated with an accidental release from
that location. The inventory of carbon tetrachloride and its proximity to
other portions of the plant and to the community should be considered when
selecting a secondary containment system. The secondary containment system
should be able to contain spills, with minimum damage to the facility and its
surroundings and with minimum potential for escalating the event.
Secondary containment systems for carbon tetrachloride storage facilities
cooconLy consist of one of the following:
• An adequate drainage system underlying the storage vessels
that terminates in an impounding basin whose capacity is as
large as that of the largest tank served.
• A diked area, with a capacity as large as that of the largest
tank served.
These measures are designed to prevent the accidental discharge of carbon
tetrachloride from spreading to uncontrolled areas.
38
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The most common type of containment system is a low-wall dike surrounding
one or more storage tanks. Generally, no more than three tanks are enclosed
within one area because of the increased r*.sk. Dike heights usually range
from three to twelve feet, depending on the area available, to achieve the
required volumetric capacity. The dike walls should be liquid tight and able
to withstand the hydrostatic pressure and temperature of a spill. Low-wall
dikes may be constructed of steel, concrete or earth. If earthen dikes are
used, dike walls must be constructed and maintained to prevent leakage.
Piping should be touted over dike walls, and penetrations through the walls
should be avoided if possible. Vapor fences nay be situated on top of tne
dikes to provide adequate vapor storage capacity. If there is more than one
tank in the diked area, the tan^s snould be ."ituated on berais auove the
maximum liquid level attainable in the impoundment.
A lw-wall dike can effectively contain the liquid portion of an acci-
dental release and keep the liquid from entering uncontrolled areas. By
preventing the liquid from spreading, the low-wall dike can reduce the surface
area of the spill. Reducing the surface area will reduce the rate of evapor-
ation. The low-wall dike will partially protect the spill from wind, whicn
can reduce the rate of evaporation. A dike with a vapor fence will provide
extra protection frexj wind and will be even more effective at reducing the
rate of evaporation.
A remote impounding basin is well-suited to storage sysrems where more
than one tank is served and where a relatively large site is available. The
flow from a carbon tetrachloride spill is directed to the basin by dikes and
channels under the storage tanks that are designed to minimize exposure of the
liquid to other tanks and to surrounding facilities. Because carbon tetra-
chloride evaporates at a relatively rapid rate, the trenches that lead to the
remote impounding basin, as well as the basin itself, should be covered to
reduce the rate of evaporation. Additionally, the impounding basin should be
located near the tank to reduce the amount of carbon tetrachloride that
evaporates as it tiavels to the basin.
39
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This type of system has several advantages. The spilled liquid ic
removed from the immediate tank area, allowing access to the tank during the
spill and reducing the probability that the spilled liquid will damage the
tank, piping, electrical equipment, pumps or other equipment.
High-wall impoundments may be a viable secondary containment choice for
selected systems. Circumstances that may warrant their use include limited
storage site area, the need to minimize vapor generation rates, and/or the
need to protect the tanks irom external hazards. Maximum vapor generation
rates will generally be lower for a high wall impoundment than for low wall
dikes or remote impoundments because of the reduced surface contact area.
These rates can be further reduced by using insulation on the wall and floor
in the annular space. High impounding walls may be constructed of low temper-
ature steel, reinforced concrete, or prestressed concrete. A weather shield
may be provided between the tank and wall, with the annular space remaining
open to the atmosphere. The available area surrounding the storage tank will
dictate the minimum height of the wall. For high-wall impoundments, the walls
may be designed with a volumetric capacity greater than that of t'.'e tank to
contBin vapors. Increasing the height of the walls also raises the elevation
of any released vapor.
One disadvantage of these dikes iu that the high walls around a tank may
hinder routine external observation. Furthermore, the closer the wall is to
the tank, the more difficult it becomes to reach the tank for inspection and
maintenance. As with low-wall dikes, piping should be routed over the wall if
possible. The closeness of the wall to the tank may necessitate placement of
pumps outside of the wall, in which case the outlet (suctior.^ lines will have
to pass through the wall. In such a situation, a low dike encompassing the
pipe penetrations and pumps nay be provided, or a low dike may be placed
around the entire wall.
One further type of secondary containment system is structurally inte-
grated with the primary system and fon&3 a vapor tight enclosure around the
primary container. Many types of arrangements are possible. A double-walled
40
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tank is an exampl? of such an enclosure. Theoe systems may be considered
where protection if the primary container and containnert of vapor for events
rot involving foundation or vail penetration failure are of greatest concern.
Drawbacks of an integrated system are the greater complexity of the structure,
the difficulty of access to certain components, and the fact that conplete
vapor containment cannot be guaranteed for all potential events.
Provisions should be made for draining rainwater from both impounding
basins and diked areas, which will involve sum^s and separate drainage pumps
since direct drainage to storm-«jater sewers would presumably allow ary spilled
carbon tetrachloride to follow the same route. Alternately, a sloped rain
hood may be used over the diked area, which could also serve to direct the
rising vapors to a single release point (15). The ground within the enclosure
should be graded to caus^ the spilled liquid to accumulate at one side or in
one corner. This will decrease the erea of ground to which the liquid is
exposed and from which it may gain heat. In areas where it is critical to
minimize vapor generation, surface insulation may be used in the diked area or
iopour.dment to further reduce heat transfer from the environment to the
spilled liquid. The floor of an impoundment aay be sealed with a clay blanket
to prevent the carbon tetrachloride from seeping into the ground; percolation
into the ground causes the ground to cool more quickly, increasing the vapor
generation rate.
4.5.2 Flotation Devices and Foacs
Other possible means of reducing the surface area of spilled chemicals
include placing impermeable flotation devices on the surface and applying
foams.
Placing an impermeable flotation device over a spilled chemical is a
direct and nearly 100 percent efficient approach for containing toxic vapors.
However, such devices must be acquired in advance of a spill and stored until
41
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needed, and in all but small spills, deployment may be difficult. In addi-
tion, material and dispersal equipment cost3 are a major deterrent to their
use (15).
The use of foan3 in vapor hazard control has been demonstrated for a
broad range of volatile chemicals (15). Unfortunately, it is difficult to
accurately quantify the benefits of foam systems because the effects will vary
as a function of the chemical spilled, foam type, spill size, and atmospheric
conditions. It has been found that: with some materials, foams have a net
positive efiects, but with others, fuams may exaggerate the hazard (15).
Little or no information is available concerning the effects and results
of foaa systems in controlling hazardous releases from carbon tetrachloride
spills. However, based on research with chemicals similar in nature to carbon
tetrachloride, a net positive effect would be expected (15). The extent of
the reduction in concentration of carbon tetrachloride will depend on the type
of foaa used. Research in this area has indicated tfcit foaas with a mediim to
high expansion ratio (300 to 350:1) give sigmficantly better results than do
foaa with low expansion ratios (6 to 8:1) (16). The expansion ratio is the
ratio of the volume of foam produced to the volume of solution fed to the
foam-generating device.
Regardless of the type of foam used, the slower the foam drainage rate,
the better its performance will be. A slew draining foio will spread more
evenly, show more resistance to temperature and pH effects, and collapse more
slowly (16). The initial cost of a slew draining foam -nay be higher than
other foaas, but a cost-effective sy3tem will be realized m superior perfor-
mance (16).
4.6 OPERATION AND MAINTENANCE PRACTICES
Accidental release of toxic materials result not only from deficiencies
of design, but also frexn deficiencies of operation. Thus, safe operation of
plants using caruon tetrachloride requires competent and experienced managers
and staff in addition to a well-considered and fully understood system of
work.
42
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Employees should be trained about the important aspects of handling
carbon tetrachloride, including: the proper means of handling and storing,
hazards resulting from improper use and handling, prevention of spills,
cleanup procedures, maintenance procedures and emergency procedures.
Weil-def.ned and planned practices and procedures can minimize the possibility
of a hazardous release and can also reduce the magnitude of an accidental
release.
Proper maintenance and modification programs should be incorporated into
plant design and operation to prevent possible hazardous releases of carbon
tet rachloride.
4.7 CGtlTROL EFFECTIVENESS
It is difficult to quantify the control effectiveness of preventive and
protective measures to reduce the probability and magnitude of accidental
releases. Pieventive measures, which may involve numerous combinations of
process design, equipment dc-sig", aid operational measures, are espe^ully
difficult to quantify because they reduce the probability ratner than a
physical quantity of a chemical release. Protective measures are more
analogous to traditional pollution control technologies. Thus, they siay be
easier to quantify in termj of their efficiency in reducing a quantity of
chemical that could be released.
Preventive measures reduce the probability of an accidental release by
increasing the reliability of both process systems operations and equipment.
Control effectiveness can thus be expressed through prooabilities for both
qualitative improvements and the quantitative improvements. Table 4-3
summarizes what appear to be some of the major design, equipment, and opera-
tional measures applicable ro hazards identified for carbon tetracnloride in
the SCAQMD. The items listed in Table 4-3 are for illustration only and do
not necessarily represent a satisfactory control option for all cases. These
control options appear to reduce the nsic asronated with an accidental
43
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TABLE 4-3. FXAMPLE? OF MAJOR PREVENTION MID PROTECTION MEASURES
FOR CARdON TETRACHLORIDE RELEASES
Hazard Area
Prevent ion/Protect ion
Water contaoination in
carbon tetrachloride feed
to chlorofluorocarbon
reactor
Carbon tetrachloride flow
control
Overheated reactor
Teoperature sensing and
heating medium {lew control
Overpressure
Corrosion
Overf i11ing
Atmospheric releasee froo
relief dischargee
Storage tank or line rup-
ture
Continuous moisture monitoring: backflov
prevention
Redundant flow control loops; oinital over-
design of feed systems; foil-close control
vaIves
Redundant temperature sensing and alarms
Redundant t<*cperature sensors; interlock flow
owit
ing
switch to shut off CCl, feed on loss of heat-
Redundant pressure relief; not isolatable;
adequate size; Jiacharge not restnc od
Inspection, maintenance, and corrosion
monitoring
Redundant level cencing. alaras and
interlocks; training of operators
Emergency vapor recovery system, tank
enclooureo
Diking; enclosure vented to vapor recovery;
foams; siting away from mechanical damage;
inspection ind non-deotrurtive testing
64
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release when viewed from a broad perspective. However, there are undoubtedly
specific cases where they will not he appropriate. Each case must be evalu-
ated individually.
A.8 ILLUSTRATIVE COST ESTIMATES FOR CONTROLS
This section presents cost estimates for different levels of controls and
for specific release prevention and protection measures that might be found in
the SCAQMD for carbon tetrachloride.
A.8.1 Prevention and Protection Measures
Preventive measures reduce the probability of an accidental release from
a process or storage facility by increasing the reliability of both process
systems operations and equipment. Increasing the reliability of a system
often increases the capital and annual costs associated with the improved
prevention and protection measures. Table A-A presents the costs of some of
the major design, equipment, and operational measures applicable to the
primary hazards identified in Table 4-3 for carbon tetrachloride applications
in the SCAQMD.
A.8.2 Levels of Control
The prevention of accidental releases relies on a combination of techno-
logical, administrative, and operational practices as they apply to the
design, construction, and operation of facilities where hazardous chemicals
are used and stored. Equipment and procedures should be in accordance with
applicable codes, standards, and regulations; however, additional measures can
be taken to provide extra insurance against an accidental release.
The levels of control concept provides a means of assigning costs to
increased levels of prevention and protection. The minimum level is referred
to as the "Baseline" system, which consists of the elements required for
normal safe operation and basic prevention of an accidental release of hazard-
ous material.
A 5
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TABLE 4-4. ESTIMATED TYPICAL COSTS OF MAJOR PREVENTION AND PROTECTION
MEASURES FOR CARBON TETRACHLORIDE RELEASES3
Prevention/Protection Measure
Capital Cost
(1985 $)
Annual Cost
(1986 $/yr)
Continuous moisture monitoring
7.500-10.000
900-1.300
Flow control loop
4.000-6.000
500-750
Temperature sensor
250-400
30-50
Pressure relief
- relief valve
1.000-2.000
120-250
- rupture disk.
1.000-1.200
120-150
Interlock system for flow shut-off
1.500-2.000
175-250
Physical barriers
- curbing
750-1,000
90-120
- 3 ft. retaining wall
1.500-2.000
175-250
Alarm system
250-500
30-75
Level sensor
- liquid level gauge
1,500-2,000
175-250
- load cell
10.000-15,000
1,300-1,900
Diking (based on a 10,000 gal. tank)
- 3 ft. hLgh
1.200-1,500
150-175
- top of tank height, 10 ft.
7,000-7,500
850-900
Increased corrosion inspection'5
200-400
aBased on a 10,000 gallon fixed carbon tetrachloride storage system and a
^2,000 gallon continuous chlorofluorocaroon reactor system.
Based on 10-20 hours at $20/hour.
46
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The second level of control is "Level 1", which includes the baseline
system with added modifications, such as improved materials of construction,
additional controls, and generally more extensive release prevention measures.
The costs associated with this level are higher than the baseline system
C06tS.
The third level of control is "Level 2". This system incorporates both
the "Baseline" and "Level l" systems with additional modifications designed
specifically for the prevention of en accidental release, such as alarm and
interlock systems. The extra accidental release prevention measures incorpo-
rated into "Level 2" are reflected in its cost6, which are ouch higher than
those of the baseline system.
When comparing the costs of the various levels of control, it is impor-
tant to realize that higher costs do not necessarily imply improved safety.
The measures applied must be applied correctly. Inappropriate modifications
or add-ons may not make a system safer. Each added control option increases
the complexity of a system. In some cases, the hazards associated with the
increased complexity may outweigh the benefits derived from the particular
control option. Proper design and construction, along with proper operational
practices are needed to ensure safe operarion.
These estimates are for illustrative purposes only. It i3 doubtful that
any specific installation would find all of the control options listed in
these tables appropriate for their purposes. An actual system is likely to
incorporate some items from each of the levels of control and also some
control options rot listed here. The purpose of these estimates is to illus-
trate the relationship between cost and control, not to provide an equipment
check list.
Levels of control cost estimates were prepared for a 25-ton fixed carbon
tetrachloride storage tank with a 10,000—gallon capacity anJ o chlorofluoro—
carbon reactor system. These systems are representative of storage and
process facilities that might be found in the SCAQMD.
47
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4.8.3 Cost Summaries
Table 4-5 summarizes the total capital and annual eo6ts for esch of the
three levels of control for a carbon tetrachloride storage system and a
chlorofluorocarbon reactor system. The costs presented correspond to the
systems described in Tables 4-6 and 4-7. Each of the level costs include the
cost of the basic system plus any controls. Specific cost information and
breakdown for each level of control for both the storage and process facili-
ties are presented in Tables 4-8 through 4-13.
4.8.4 Equipaent Specifications and Detailed Cogrs
Equipment specifications and details of the capital cost estimates for
the carbon tetrachloride storage and the chlorofluorocarbon reactor systems
are presented in Tables 4-14 through 4-21.
4.8.5 Methodology
Format for Presenting Cost Estimates—
Tables are provided for control schemes associated with storage and
process facilities for carbon tetrachloride showing capital, operating, and
total snnual costs. The tables are broken down into subsections for vessels,
piping and valves, process machinery, instrumentation, and procedures and
practice. Presentation of the costs in this manner allows for easy comparison
of specific items, different levels, and different systems.
Capital Cost—All capital costs presented in this report are shown as
total fixed capital costs. Table 4—22 defines the cost elements comprising
totcl fixed capital as it is used here.
The computation of total fixed capital, as shown in Table 4-22, begins
with the total direct cost for the system under consideration. This total
direct cost is the total direct installed cost of all capital equipment
comprising the system. Depending on the specific equipment item involved, the
48
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TABLE 4-5. SUMMARY OF 00ST ESTIMATES 0? POTENTIAL LEVELS OF CONTROL FOR
CARSON TETRACHLORIDE STORAGE TANK AND CHLOROFLUOROCARBON
REACTOR SYSTEMS
Total Total
Level of Capital Cost Annual Cost
Control (1986 $) (1986 S/yr)
Carbon Tetrachloride Storage Tank;
25 ton Fixed Carbon
Tetrachloride Tanit With
10,000 gal Capacity
Baseline
Level No. 1
Level No. 2
5 9.000
254,000
31 9.000
7.600
30.000
38.000
Continuous Chlorofluorocarbon
Reactor System With
2,000 gal Capacity
Baseline
Level No. 1
Level No. 2
111,000
353.000
43 2,000
15.000
43,000
54.000
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TABLE 4-6. EXAMPLE OF LEVELS OF CONTROL FOR CARBON TETRACHLORIDE STORAGE TAfK
Process: 25 ton fixed carbon tetrachloride storage tank (10,000 gal)
Cont rols
Baseline
Level No. 1
Level No. 2
Process:
Flow:
None
Single check valve on
tank-pcoces6 feed line.
None
Add second check valve.
None
Add a reduced-pressure
device with internal air
gap and relief vent to
incinerator.
Temperature:
Pressure:
Quantity:
Location:
Materials of
Const ruct ion:
Vescel
Piping:
Hone
Free flow atmospheric
vent.
Local level indicator.
Away from traffic.
Fiber-reinforced plastic
(FRP).
Fixed roof atmospheric
tank.
Schedule 40 carbon steel.
Add conservation valve.
Vent to refrigerated con-
denser.
Add remote level indicator.
Away from traffic and
other hazardous processes.
Fiber-reirforced plastic
(FRP).
Fixed roof tank with in-
ternal floating roof.
Schedule 80 Saran®-lined
carbon steel.
Add temperature indicator.
Add systeos disk, provide
local pressure indication
on space between disk and
valve, vent to inciner-
ator.
Add level alarm. Add
high-low level interlock
shut-off for both inlet
and outlet line.
Away from traffic and
other hazardous processes.
Monel® clad carbon steel.
Low pressure storage tank
with pressure specifica-
tion of 25 psig.
Schedule 80 Monel®.
(Continued)
-------
TABLE 4-6 (Continued)
Process: 25 ton fixed carbon tetrachloride storage tank (10,000 gal}
Controls
Easeline
Level No. 1
Level No. 2
Piocess
Machinery:
Centrifugal pump, carbon
steel construction,
stuffing box.
Centrifugal pucip, Konel®
construction, double sech-
anical seal.
Magnetically-coupled cen-
trifugal pump, Monel® con-
st ruction.
Enclosures:
None
Steel building.
Concrete building.
Diking
None
3 ft high.
Top of tank height, 10 ft.
Containment
Hone
Refrigerated condenser.
Same
Hit igat ion
None
Foam system.
Same
-------
TABLE 4-7. EXAMPLE OF LEVELS OF CONTROL FOR CHLOROFLUOROCARBON REACTOR SYSTEM
Process: Chlorofluorocarbon Manufacture
Typical Operating Conditions: - Temperature: 176°F
Pressure: 100 pslg
Controls
Baseline
Level Ho. 1
Level No. 2
Process:
Temperature:
Pressure:
Flow:
Quant ity:
Mix ing:
Corrosion:
Dryers on carbon
tetrachloride feed line.
Provide local temperature
control.
Single pressure relief
valve. Vent to
atmosphere.
Provide local fl->w
control on carboi
tetrachloride fe'd and
heating medium to
reactor.
None
Provide adequate rising.
Visual inspections.
Improved reactor design.
Add redundant
temperature senso:s a.nd
alarms. Add remote
ind icator.
Add redundant pressure
sensors. Add second
relief valve. Vent to
vapor recovery system.
Add remote pressure
indicator.
Add redundont flow
control loops.
None
Add alarm on loss of
recirculating pump
Increased inspections
and monitoring.
Add interlock and
backup cooling system.
Add temperature switch
to shut off carbon
tetrachloride feed.
Add system disks under
relief valves and
provide local and
remote pressure
indication on 6pace
between disk and valve.
Add interlock flow
switch to shut off
carbon tetrachloride
feed.
Level alarm.
Interlock carbon
tetrachloride feed on
loss of mixing.
Same
(Cont inued)
-------
TABLE A-7 (Continued)
Process: Chlorofluorocarbon Manufacture
Typical Operating Conditions: - Temperature: 176°F
Pressure: IOC psig
Cont rols
Baoeline
Level No. 1
Level No. 2
Compos i t ion:
Materials of
Construct ion:
Dryers on carbon
tetrachloride feed line.
Carbon steel.
Occasional moisture
monitoring of feed.
Carbon steel with added
corrosion allowance.
Continuous moisture
monitoring of feed.
Monel®-clad carbon
steel.
Vessel:
Piping:
Pressure specification:
150 psig.
Sch. 80 carbon steel
Pressure specification:
200 psig.
Sch. 80 Saran®-lined
carbon steel.
Pressure specification:
300 psig.
Sch. 80 Monel®.
Process
Machinery:
Centrifugal pump, carbon
steel construction,
stuffing box.
Centrifugal pump. Monel®
construction, double
capacity mechanical
cea 1.
Magnetically-coupled
centrifugal pump,
Monel® construction.
Protect ive
Barrier:
None
Curbing around
reactor/settler.
3 ft. high retaining
wal 1.
Enclosure: None
Vapor Recovery None
System:
Steel building.
Refrigerated condenser.
Concrete building.
Same
Mit igation:
None
Foam system.
Same
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TABLE 4-8. ESTIMATED TYPICAL CAPITAL AND ANNUAL COSTS ASSOCIATED WITH
BASELINE CARBON TETRACHLORIDE STORAGE SYSTEM
Capital Cost Annual Coot
(1986 S) (1986 $//r)
Vessels:
Storage Tank 36.000 A. 200
Piping and Valves:
PlPeuork 4,500 520
Check Valves 520 60
Ball Valves (5) 3,200 370
Process Machinery:
Centrifugal Puap 11,000 1.200
Instrumentation:
Pressure Gauges (4) 1.500 170
Liquid Level Gauge 1.500 170
Procedures and Practices:
Visual Tank Inspection (external) 15
Visual Tank Inspection (internal) 60
Relief Valve Inspection ^5
Piping Inspection -jqO
Piping Maintenance 120
Valve Inspection 30
Valve Maintenance 35O
Total Costs 5 9.000 7.600
54
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TABLE 4-9. ESTIMATED TYPICAL CAPITAL AJJD AI/I1UAL COSTS ASSOCIATED WITH
LEVEL 1 CARBON TETRACHLORIDE STORAGE SYSTEM
Capital Cost Annual Cost
(1986 $) (1986 S/yr)
Vessels:
Storage Tank 48,000 5,500
Piping and Valves:
Pipework. 6,200 720
Check Valves 1,100 120
Ball Valves (5) 3.200 370
Relief Valve 2,000 230
Process Machinery:
Centrifugal Puap 25.000 3,000
Inst ruaentation:
Pressure Gauges (4) 1,500 170
Flow Indicator 3,700 430
Liquid Level Gauge 1.500 170
Remote Level Indicator 1,900 220
Enclosures:
Steel Building 10,000 1,200
Vapor Recovery Systea: 150,000 17,000
Diking:
3 ft. High Concrete Diking 1,300 160
Procedures and Practices:
Visual Tank Inspection (external) 15
Visual Tank Inspection (internal) 60
Relief Valve Inspection 30
Piping Inspection 300
Piping Maintenance 120
Valve Inspection 35
Valve Maintenance 400
Total Costs 254,000 30.000
55
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TA3LE 4-10. ESTIMATED TYPICAL CAPITAL AMD AJ11JUAL COSTS ASSOCIATED WITH
LEVEL 2 CARBON TETRACHLORIDE STORAGE SYSTEM
Capital Cost Annual Cost
(1986 S) (1986 $/yr)
Vessels:
Storage Tank 64,000 7.500
Piping and Valves:
Pipework 9.200 1.100
Check Valves 2,700 310
Ball Valves (5) 3,200 370
Relief Valve 2.000 230
Rupture Disa 600 70
Process Machinery:
Centrifugal Pusd 32,000 3,700
Instruaentation:
Temperature Indicator 1,800 220
Pressure Gauges (6) 2,200 260
Flow Indicator 3,700 430
Load Cell 16,000 1,800
Reaote Level Indicator 1,900 220
Level Alars 740 90
High-Low Level Shut off l.SOO 220
Enclosures:
Concrete Building ISO.000 1,700
Vapor Recover/ Systea: 150.000 17.000
Diking:
10 ft. High Concrete Dike 7.400 870
Procedure: and Practices: 7,400
Visual Tank Inspection (external) 15
VicuaL Tank Inspection linternal) 60
Relief Vai/e Inspection 5C
Piping Inspection 300
Piping Maintenance 120
Valve Inspection 35
Valve Maintenance 400
Total Costs 319.000 38,000
56
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TABLE 4-11. FSTIMATtD TYPICAL CAPITAL AND ANNUAL COSTS ASSOCIATED WITH
BASELINE GILOPr.FLUOROCARBON KEACTOR SYSTEM
Capital Cose Annual Cose
(1986 $) (1986 $/yr)
Equipoent:
Reactor and Feed Dryer 63,000 7,600
Piping and Valves:
Pipework 6,800 800
Ball Valves (8) 5,000 600
Relief Valve 2,000 230
Process Machinery:
Centrifugal Punpa (2) 20,000 2,400
Instrumentation:
Pressure Gauges (3) 1,100 129
Local Temperature Indicator 1,800 220
Flow Control Loop (2) 11,000 1,300
Maintenance and Inspections:
Visual Tower Inspection (external) 15
Visual Tower Inspection (internal) 60
Piping Inspection 900
Piping Maintenance 360
Valve Inspection 30
Valve Maintenance 350
Total CoGto 111,000 15,000
57
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TABLE 4-12. ESTIMATED TYPICAL CAPITAL AND A!J»JUAL COSTS ASSOCIATED WITH
LEVEL 1 GlL0R0f,"LU0R0CAR3ON REACTOR SYSTEM
Capital Coat Annual C?sr
(1986 $) (1986 5/yr)
Equipment:
Reactor and Dryers
Piping and Valves:
Pipework
Ball Valves (3)
Relief Valves (2)
Process Machinery:
Centrifugal Pumps (2)
84.000
28.000
5.000
4.000
49.000
10,000
3,300
600
450
5.900
Inutrusiuntation:
Pressure Caugcs
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TABLE 4-13. ESTIMATED TYPICAL CAPITAL AND ANNUAL COSTS ASSOCIATED WITH
LEVEL 2 CHLOROFLUOROCARflOfJ REACTOR SYSTEM
Capital Cost Annual Cost
(1986 S) (1986 $/yr)
Equipment:
Reactor and Dryers 115,000 14,000
Piping and Valves:
Pipework 40,000 4,800
Ball Valves (8) 5,000 600
Relief Valves (2) A,000 470
Rupture Disks (2) 1,200 140
Process Machinery:
Centrifugal Pumps (2) 62,000 8,000
Inst rumentation:
Pressure Gauges (3) 1.100 130
Level Alarm 360 45
Local Temperature Indicator 1.800 220
Remote Temperature Indicator 1,800 220
Temperature Sensor 360 45
Temperature Alarm 360 45
Temperature Srficch 540 65
Flow Interlock System 1,800 ?20
Flow Control Loops (4) 22,000 2,600
Moisture Alarm 360 45
Moisture Monitoring System 9,000 1,100
Diking:
0.9a (3 ft.) High Retaining Wall 3,000 360
Enclosure:
Concrete Building 16,000 2,200
Vapor Recovery System: 144,000 17,000
Maintenance and Inspections:
Visual Tower Inspection (external) 15
Visual Tower Inspection (internal) 60
Piping Insoection 900
Piping Maintenance 360
Valve Inspection 30
Valve Maintenance 350
Total Costs 432,000 54,000
59
-------
TABLE 4-14. EQUIPMENT SPECIFICATIONS ASSOCIATED WITH CARBON TETRACHLORIDE
STORAGE SYSTEM
Equipment Item
Equipment Specification
Reference
VESSELS:
Storage Tank
PIPING AND VALVES:
Pipework
Check valve
Ball valve
Relief valve
Reduced pressure
device
Process Machinery
Baseline: 10,000 gal carbon steel 14,17,18,
fixed roof atmospheric tank. 19,20
Level 01: 10,000 gal fiberglass-
reinforced plastic fixed roof tank with
floating roof.
Level 62: 10,000 gal Monel®-clad
carbon steel tank.
Baseline: 100 ft of 4-in 21
Schedule 40 carbon steel.
Level 61: 4-in Schedule 40
Saran®-lined carbon steel
Level 92: 4-in Schedule 80
Monel®.
4-in vertical lift check valve, 18,22
Monel® trim.
4-in Class 300, flanged, Monel® 17,18
ball and stem.
1-in x 2-in Class 300 inlet and 18
outlet flange, angle body,
closed bonnet with screwed cap, Monel®
trim.
Double check valve typo device with 17
internal air gap and relief valve.
Baseline: Single stage, carbon steel 18,23
construction, stuffing box, 100 gpm
capacity.
Level #1: Single stage, Monel® con-
struction, double mechanical seal.
(Continued)
60
-------
TABLE 4-14 (Continued)
Equipment Item
Equipment Specification
Reference
INSTRUMENTATION:
Temperature indi-
cator
Pressure gauge
Flow indicator
Liquid level gauge
Load cell
Level alarm
High-low level
shutoff
ENCLOSURES:
Bui1ding
DIKING:
VAPOR RECOVERY
SYSTEM:
Level 2: Monel® construction, magne- 18,23
tically-coupled, 100 gpm capacity.
Thermocouple, thennowell, electronic 17,18,24
indicator.
Diaphragm sealed, Monel® diaphragm, 17.18 24
. 0-1,000 psi.
Differential pressure cell, trans- 17,24
mitter, and associated flowmeter.
Differential pressure type level gauge. 17.24
Electrically operated load cell with 17,24,25
electronic indicator.
Indicating and audible alarm. 18,26,27
Solenoid valve, switch, and relay system. 17,18,24,
26
Level 01: 26 gauge steel walls and roof, 26
door, ventilation system.
Level 02: 10-in concrete walls,
26 gauge steel roof. door.
Level SI: 6-in concrete walls, 26
3 ft high.
Level Q2: 10-in concrete walls,
top of tank height, 10 ft.
Le^el 1 and 2: 2 ton refrigeration, 100 14,28
ft condensor, vapor recovery system.
61
-------
TABLE 4-15. MATERIAL AND LABOR COSTS ASSOCIATED WITH BASELINE CARBON
TETRACHLORIDE STORAGE SYSTEM
Materials
Cost
Labor
Cost
Direct
Costs
Indirect
Costs
Capital
Cost
(1986 $)
VESSELS:
Storage Tank
16,000
8.000
24.000
8.400
36,000
PIPING AND VALVES:
Pipework
900
2. 100
3.000
1.100
4.500
Check Valves
320
30
350
120
520
Ball Valves (5)
2.000
150
2,150
750
3,200
PROCESS MACHINERY:
Centrifugal Pump
4,900
o
o
CM
7.000
2,500
11,000
INSTRUMENTATION:
Pressure Gauges (4) 800 200 1,000 350 1,500
Liquid Level Gauge 800 200 1.000 350 1.500
Total Costs 26,000 13,000 39.000 14.000 58.000
62
-------
TABLE 4-16. MATERIAL AND LABOR COSTS ASSOCIATED WITH LEVEL 1 CARSON
TETRACHLORIDE STORAGE SYSTEM
Materials
Cose
Labor
Cost
Direct
Costs
Indirect
Costs
(1986 S)
Capital
Cost
VESSELS:
Storage Tank
PIPING AND VALVES:
Pipework
Check Valves
Ball Valves (5)
Relief Valve
PROCESS MACHINERY:
Centrifugal Pomp
INSTRUMENTATION:
Pressure Gauges (4)
Flow Indicator
Liquid Level Gauge
Remote Level
Indicator
ENCLOSURES:
Steel Building
VA^OR RECOVERY SYSTEM:
DIKING:
3 ft. High
Concrete Diking
Total Costs
22.000
3.300
640
2.000
1.300
12.000
800
2,000
800
1,000
4,600
70.000
390
10.000 32.000 11.000 48.000
860
60
150
50
200
500
200
250
510
4,160
700
2,150
1,350
1.000
2.500
1.000
1.250
1.500
250
750
460
5.000 17,000 6,000
350
880
350
430
2.300 6,900 2.400
900
320
6.200
1.100
3.200
2.000
25. 000
1.500
3.700
1.500
1.900
10.000
30.000 100,000 35.000 150.000
1.30C
121.000
50.000 171,000 60.000 254.000
63
-------
TABLE 4-17. MATERIAL AND LABOR COSTS ASSOCIATED UITH LEVEL 2 CARBON
TETRACHLORIDE STORAGE SYSTEM
Materials Labor Direct Indirect Capital
Cost Cost Costs Costs Cost
(1936 $)
VESSELS:
Storage Tank
PIPING AND VALVES:
Pipework
Reduced Pressure
Device
Ball Valves (5)
Relief Valve
Rupture Disk
PROCESS MACHINERY:
Centrifugal Pumo
INSTRUMENTATION:
Temperature
Indicator
Pressure Gauges (6)
Flow Indicator
Load Cell
Remote Level
Indicator
Level Alarm
High-Low Level
Shutoff
ENCLOSURES:
Concrete Building
VAPOR RECOVERY SYSTEM:
DIKING:
10 ft High
Concrete Dike
30,000
A. 800
1,600
2,000
1,300
350
15,000
1.000
1,200
2,000
8,400
1,000
400
1.000
6,100
70,000
2.200
13.000 43,000 15.000
1,400
200
150
50
50
250
300
500
2, 100
250
100
250
6,200
1.800
2.150
1,250
400
6,400 21,400
1,250
1,500
2,500
10,500
1.250
500
1.250
2,200
630
750
460
140
7,500
310
530
880
3.700
440
180
440
6.600 12.700 4.500
30.000 100.000 35.000
2,800 5,000
1,800
64,000
9,200
2,700
3,200
2,000
600
32,000
1,800
2,200
3.700
16.000
1. 900
740
1,900
19,000
150,000
7,400
Total Costs
14 9,000
65,000 214,000 75,000 319,000
64
-------
TABLE 4-18. EQUIPMENT SPECIFICATIONS ASSOCIATED WITH CHLOROFLUOROCARBON
STORAGE SYSTEM
Equipment Item
Equipment Specification
Reference
VESSELS:
Reactor
Feed Dryers
PIPING AND VALVES:
Pipework
Ball valves
Relief valves
Rupture disk
PROCESS MACHINERY:
Centrifugal pump
INSTRUMENTATION:
Temperature sensor
Temperature alarm
Temperature switch
2,000 gal continuous reactor
system including system catalyst
Sieve dryers or equivalent on carbon
tetrachloride feed 6tream
Baseline: 300 ft of 4 in Schedule 80
carbon steel
Level 1: 4-in Schedule 80 Sar8n®-
lined carbon steel
Level 2: 4-in Schedule 80 Monel®
4-in Class 300, flanged, carbon
6teel construction
2-in x 3-in Class 300 inlet and
outlet flange angle body, closed
bonnet with screwed cap, carbon steel
body, Monel® trim
2-in Monel® disk and c-rbon steel
holder
Baseline: Single stage, carbon steel
construction, stuffing box
Level 1: Single stage, Monel® construc-
tion, double mechanical seal
Level 2: Monel® construction, magnet-
ically-coupled
Thermocouple and associated thennowell
Indicating and audible alarm
Two-stage switch with independently set
actuation
17
17
21
17,18
18
24,29
18,23
18.23
17.18,24
18.26,27
17.24
(Continued)
55
-------
TABLE 4-18 (Continued)
Equipment Item
Equipment Specification
Reference
Remote temperature
indicator
Remote pressure
indicator
Pressure guage
Flow control loop
Flow interlock
system
Level alarm
Moisture monitor-
ing system
DIKING:
VAPOR RECOVERY
SYSTEM:
Transmitter and associated electronic
indicator
Transducer, transmitter and electronic
indicator
Diaphragm sealed. Hastelloy C diaphragm,
0-1,000 psi
4-in globe control valve. Morel*
trim, flowmeter and PID controller
Solenoid valve, switch, and relay system
Indicating and audible alarm
17,24
17,24
17,18,24
17,24
17,18.24,
26
18,26,27
Capacitance or infrared absorption system 25
Level 1: 6-in high concrete curbing 26
Level 2: 3-ft nigh concrete retaining
tall
Le^el 1 and 2: 2-con refrigeration, 100- 14,28
ft condensor, vapor recovery system.
66
-------
TABLE A-19. MATERIAL AND LABOR COSTS ASSOCIATED WITH BASELINE
CHLORDFLUOkOCARBON REACTOR SYSTEM
Materials Labor Direct Indirect Capital
Cos t Cost Costs Costs Cost
(1986 S)
EQUIPMENT:
Reactor and Feed
Dryer 30.000 1A,000 AA,000 11.000 63,000
PIPING AND VALVES.
Pipework 1.700 3.000 A.700 1.200 6.800
Ball Valves (8) 3.200 300 3.500 880 5.000
Relief Valve 1.300 50 1.350 340 2,000
PROCESS MACHINERY:
Centrifugal
p"aps (2) 10.000 A,000 1A,000 3.500 20,000
INSTRUMENTATION:
Pressure Gauges (3) 600 150 750 190 1,100
Local Temperature
Indicator 1.000 250 1.250 310 1.800
Flow Control
Loop (2) 6.000 1.500 7.500 1.900 11,000
Total Costs 5A.00O 23.000 77.000 20.000 111,000
67
-------
TABLE 4-20. MATERIAL AND LABOR COSTS ASSOCIATED WITH LEVEL 1
CHLOROFLUOROCARBON REACTOR SYSTEM
Materials
Cost
Labor
Cost
Direct
Costs
Indirect
Costs
Capital
Cost
(1936 S)
EQUIPMENT:
Reactor and Dryers
AO.000
18.000
58.000
15.000
84.000
PIPING AND VALVES:
Pipework
15.000
4.000
19.000
4. 800
28.000
Ball Valves (8)
3.200
300
3.500
880
5.000
Relief Valves (2)
2.600
100
2.700
680
4.000
PROCESS MACHINERY:
Centrifugal
Puaps (2)
24.000
10.000
34.000
3.500
49.000
INSTRUMENTATION:
Pressure Gauges (3)
600
150
750
190
1. 100
Local Temperature
Indicator
1,000
250
1.250
310
1.800
Temperature Sensor
200
50
250
60
360
Temperature Alarm
200
50
250
60
360
Flow Control
Loops (4)
12.000
3.000
15,000
3.800
22.000
Moisture Alarm
200
50
250
60
360
DIKING:
Curbing Around
Tower
500
350
850
210
1.200
ENCLOSURE:
Steel Building
4.600
2.300
6. 900
1.700
10.000
VAPOR RECOVERY SYSTEM:
70.000
30.000
100,000
25.000
145,000
Total Cost3
174.000
69.000
243.000
62.000
353.000
68
-------
TABLE 4-21. MATERIAL AMD LABOR COSTS ASSOCIATED WITH LEVEL 2
CHLOROFLUOROCARBON REACTOR SYSTEM
Materials
Coat
Labor
Cost
Direct
Costs
Indirect
Costs
Capital
Cost
<1936 S)
EQUIPMENT:
Reactor and Dryorn
55.000
25,000
80.000
20,000
115.000
PIPING AND VALVES:
Pipework
22,000
6.000
28,000
7.000
40,000
Boll Valvec (8)
3.20C
300
3,500
880
5.000
Relief Valvec (2)
2,600
100
2,700
680
4,000
Ruptjre Diiko (2)
;oo
100
800
200
1. 200
PROCESS MACHINERY:
Centrifugal Puapo (2)
30.000
12. 800
42.800
11,000
62,000
INSTRUMENTATION:
Pressure Gauges (3)
600
150
750
190
1.100
Level Alann
200
50
250
60
350
Local Tesperacuru
Indicator
1,000
250
1.250
310
1.800
Remote Temperature
Indicator
1,000
250
1,250
310
1. J00
Temperature Senisor
200
50
250
60
360
Temperature Aluna
200
50
250
60
360
Temperature Switch
300
75
375
95
540
Flow Interlock
Syctea
1,000
250
1.250
310
1.800
Flow Control
Loops (4))
12.000
3.000
15.000
3.800
22.000
Moisture Alarm
200
50
250
60
360
Moisture Monitoring
Systea 5.000 1,250 6,250 1.600 9.000
DIKING:
3 ft High
Retaining Wall 900 1» 200 2. 100 530 3.000
CCont z.nued)
69
-------
TABLE 4-21 (Continued)
Materials Labor Direct Indirect Capital
Cog t Cost Costs Costs Cost
(1936 S)
ENCLOSURE:
Concrete Building 6,000 6,600 12,600 3,200 18,000
VAPOR RECOVERY SYSTEM: 70,000 30,000 100,000 25,000 144,000
Total Costs 212,000 88.000 300,000 75,000 432,000
70
-------
TABLE 4-22. FORMAT FOR TOTAL FIXED CAPITAL COST
Iten No. Item Cost
1 Total Material Coct
2 Total Labor Coot
3 Total Direct Coot Iteos 1+2
4 Indirect Cost Iteos (Engi-
neering & Construction
Expences) 0.35 x Iten 3a
5 Total Bare Module CoGt Iteos (3 + 4)
6 Contingency (0.05 x Iten 5)^
7 Contractor's Fee 0.05 x Iten 5
8 Total Fixed Capi.al Cost Iteos (5+6+7)
a
For storage facilities, the indirect coct factor is 0.35. For proceco
facilities, the indirect coat factor is 0.25.
b For storage facilitieo. the tcntingency cost factor is 0.0!>. For process
facilities, the contingency coot factor is 0.10.
7 I
-------
direct capital cost was available or was derived fron tirinstalled cocts by
cocputing costs of installation separately. To obtain the total fixed capital
C'iGt, other costs obtained by using factors are added to the total fixed
direct costs.
Tbe first group of other cost eleoents is indirect costs. These include
engineering and supervision, construction expenses, and various other expenses
iueh as adninistration expenses. These cocts are cooputed by multiplying
total airect costs by a factor shown in Table 4-?2. The factor is opproxi-
oate. is obtained from the cost literature, and is based on previous experi-
ence with capital projects of a similar r.ati;r". Factors can have a range of
values and vary according to tecb^olc^y area and for individual technologies
within an area. Based on judgeeent and experience, appropriate factors were
selected for use in this report.
T?ie cum of indirect costs and total direct costs equals total bare oo
-------
TABLE 4-23. FORMAT FOR TOTAL ANNUAL COST
Item Item cost
1 Total Direct Cost —
2 Capital Recovery on Equip-
ment Items 0.163 x Item 1
3 Maintenance Expense on
Equipment Items 0.01 x Item 1
4 Total Procedural Items
5 Total Annual Cost Items (2+3+4)
73
-------
sources and references where necessary. Adjustments were made to update all
costs to June 1986 dollars. For seme equipment items, well-documented costs
were not availabLe; these had to be deveLoped from component costs.
Costs in this document reflect the "typical" or "average" costs for
specific equipment items. This restricts the usa of data in this report to;
• Preliminary estimates used for policy planning;
• Comparison of relative costs of different levels or systems;
and
• Approximations of costs that eight be incurred for a specific
application.
Costs in thiS report are considered to be "order of magnitude" with a +50
percent margin because they are based on preliminary estimates and many are
updated from literature sources. Large departures from the design basis of a
particular system presented in this manual or the advent of a different
technology might cause the system cost to vary more than this. If used as
intended, however, this document will provide a reasonable source of prelimi-
nary cost information for the facilities covered.
When comparing costs in this taanual to those from other references, the
user should be sure the design bases are comparable and that the capital and
annual costs «s defined here are the same.
Cost Updating—
All costs in this report are expressed in June 1986 dollars. Costs
reported in the literature were updated using cost indices for materials end
labor.
34
-------
Costs expressed in base-year dollars nay be adjusted to dollars for
another year by applying cost indices as shown in the following equation:
. , . , _ new base year index
new base-year cost = old base-year cost x , . . 1 :—:—
old base year index
The Chemical Engineering (CE) Plant Cost Index was used to update costs for
this report. For June 1986, the index is 316.3.
Equipment Costs—
Most of the equipment costs presented in this manual were obtained
directly from literature sources of vendor information and correspond to a
specific design standard. Special cost estimating techniques, however, were
used in determining the costs associated with vessels, piping systems, vapor
recovery systems, diking, and enclosures. The techniques are presented in the
following subsections of this manual.
Vessels—The total purchased cost for a vessel, as dollars per pound of
weight of fabricated unit free on board (f.o.b.) with carbon steel as the
basis (January 1979 dollars) were determined using the following equation from
Peters and Timmerhaus (17):
Cost = {50 (Weight of Vessel in Pounds) ^.34j [Weight of Vessel in Pounds]
The vessel ucight is determined using appropriate design equations, as given
by Peters and Timmerhaus (17) that allow for vjii thickness adjustments for
corrosion allowances, for example. The vessel weight is increased by a factor
of 0.15 for horizontal vessels and 0.20 for vertical vessels to account for
the added weight of nozzles, manholes, and skirts or saddles. Appropriate
factors are applied for different materials of construction as given in Peters
and Tiiamerhaus (17). Vessel costs are updated using coct factors. Finally, a
shipping cost amounting to 10 percent of the purchased cost is add°d to obtain
the delivered equipment cost.
75
-------
Piping Piping costs were obtained from cost information and data pre-
sented by Yamartino (21). The simplified approach used assumes that a certain
length of piping containing a given number of valves, flanges, and fittings is
contained in the storage or process facility. The data presented by Yaoartino
(21) permit cost determinations for various lengths, cize6» and types of
piping systems. Using these factors, a representative estimate can be ob-
tained for each of the storage and process facilities.
Diking—Diking costs were estimated using Mean's Manual (26) for rein-
forced concrete walls. The following assumptions were made to determine the
costs. The dike contains the entire contents of a tank in the event of a leak
or release. Two dike sizes are possible: a three-foot high dike, six-inches
thick, and a top-of-tank height dike ten inches thick. The tanks are raised
off the ground and are not volumetrically included in the volume enclosed by
the diking. These assumptions facilitate cost determination for any size
diking system.
Erclosures—Enclosure costs were estimated using Mean's Manual (26) for
both reinforced concrete and steel-walled buildings. The buildings are
assumed to enclose the same area and volume as the top-of-tank height dikes.
The concrete building is ten-inches thick with a 26-gauge steel roof and a
ootal door. The steel building has 26 gauge roofing and siding and metal
door. The cost of a ventilation system was determined uoi.ig a typical 1,000
scfm unit and doubling the cost to account for duct work and requirements for
the safe enclosure of hazardous chemicals.
Vepor Pecovery Systems A refrigerated condenser system cost was eoti-
mated using a technique developed by Vatavuk and Ncveril (28) based on the
amount of refrigerarion required for a given situation. The refrigeration and
condenser area requirements were obtained from reference (16) based on a giver,
storage facility.
76
-------
Installation Factors—
Installation costs were developed for all equipment items included in
both the process and storage systems. The costr. include both the material and
labor costs for installation of a particular piece of equipment. Costs were
obtained directly from literature sources and vendor information or indirectly
by assuming a certain percentage of the purchased equipment cost by using
estimating factors obtained from Peters and Timmerhaus (17) and Valle-Riestra
(31). Table 4-24 lists the cost factors used or the reference from which the
cost was obtained directly. Many of the costs obtained from the literature
were updated to June 1986 dollars using a 10 percent per year rate of increase
for labor and cost indices for materials associated with installation.
77
-------
TABLE 4-24. FORMAT FOR INSTALLATION COSTS
Equipment Tceo Factor or Reference
Vessels:
Storage Tank
Piping and Valves:
Pipework
Reduced Pressure Devico
Check Valves
Gate Valves
Ball Valves
Relief Valves
Rupture Disks
Process Machinery:
Centrifugal Pump
Gear Pump
Inst rumentat ion:
All Instrumentation Items
Enclouures:
Diking:
Vapor Recovery:
78
0.45
Ref. 21
Ref. 18
Ref. 18
Ref. 18
Ref. 18
Ref. 18
Ref. 18
0.43
0.43
0.25
Ref. 26
Ref. 26
0.45
-------
SECTIOH 5
REFERENCES
1* South Coast Air Quality Management District, File of Questionnaires from
Toxic Cheaucal Industry Survey, 1955.
2. Kirk, R.E., and Ottmers. D.F., Encyclopedia of Chemical Technology, 3rd
Edition, Vol. 10, John Wiley 4 Sens. Inc.. 1930.
3. Chloroform. Carbon Tetrachloride, and Other Halomethanes: An Environmen-
tal Assessment. National Academy of Sciences. Washington, DC. 1978.
4. Dean. J. (ed). Lange's Handbook of Chemistry. Twelfth Edition, McGraw-
Hill Book Company, tlew YorK, NY. 1975.
5. Bird, R.B., J.E. Stewart, and E.N. Lightfoot. Transport Phenomena. John
Wiley & Sons, 1960.
6. Von Oettmgen, W.F., The Halogenated Hydrocarbons of Industrial and Toxi-
cological Importance. Elsevian Publisning Company, NY. 1964.
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Substances (RTECS). 1981. 82 edition, 3 volumes, NIOSH Contract No. 210-
81-8101. DtlrlS (NIOSH) Publ. No. 83-107, June 19<53.
8. U.S. Environmental Protection Agency. Health Assessment Document for
Carbon Tetrachloride: Environmental Criteria and Assessment Office, OH.
Publication No. EPA-600/8-82-001F. 1934.
9. NI0SH/0SHA Pocket Guide to Chemical Hazards. DHEW (NIOSH) Publication
No. 78-210, Sept
-------
14. Erikson, D.G. (IT Enviroscience, Inc.) et al. Organic Chemical Manufac-
turing Volume 3: Storage, Fugitive, and Secondary Sources.
EPA-450/3-80-025 (NT1S PB81-220527). December 1980.
15. Bennett, G.F.t F.S. Feates. and I. Wilder. Hazardous haterial Spills
Handbook. McGraw-Hill Book Company, New York, MY, 1982.
16. Hiltz, R.H., and S.S. Gross. The Use of Foams to Control the Vapor Haz-
ard From Liquified Gas Spills. Proc. of Control of Hazardous Material
Spills, Louisville, KY, May 1980.
17. Peters, M.S., and X.D. Timaerhaus. Plant Design and Economics for Chemi-
cal Engineers. McGraw-Hill Book Company, New York, MY, 19fcJ0
18. Richardson Engineering Services, Inc. The Ricnardson Rapid Construction
Cost Estimating System, Vol. 1-4, San Marcos, CA, 1986.
19. Pikulik, A., and H.E. Diaz. Cost Estimating for Major Process Equipaent,
Cheaical Engineering, October 10, 1977.
20. Hall, R.S., J. Matley, and K..J, McNaughton, Cost of Process Equipment,
Cheaical Engineering, April 5, 1982.
21. Yaff irtino, J. Installed Cost of Corrosion - Resistant Piping - 1978.
Chemical Engineering November 20, 1978.
22. Telephone conversation between J.D. Quass of Radian Corporation and e
representative of Maik Controls Corporation, Houston, TX. August 1986.
2J. Green, D.W. (ed). Perry's Cheaical Engineers' Handbook (Sixth Edition).
McGraw-Hill Boo* Company, Hew York, NY. 1984.
24. Liptak, 3.G. Costs of Process Instruments. Chemical Engineering,
September 7, 1970.
25. Liptak, B.G. Costs of Viscosity, Weight. Analytical Instruments. Chemi-
cal Engineering, September 21, 1970.
26. R.S. Means Company, Inc., Building Construction Cost Data 1986 (44th
Edition), Kmgscon, MA.
27. Liptax, B.G. Control - Panel Costa. Process Instruments. Chemical Engi-
neering. October 5, 19/0.
23. Vatavuit, J.M. and R.3. N'everil. Part XVI: Costs of Refrigeration Sys-
tems, Cheaical Engineering, May 16. 1985.
29. TeLephone conversation between J.D. Quaes of Radian Corporation and a
representative of Fike Corporation, Houston. TX, August 1986.
80
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30. Cost indices obtained from Chemical Engineering. McGraw-Hill Publishing
Company, New York., NY, June 1974, Deceaber 1985, and August 1936.
31. Valle-Riestra, J.F., Project Evaluation in the Chemical Process Indus-
tries. McGraw-Hill Boole Compan/, New York, NY, 1983.
81
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APPENDIX A
GLOSSARY
This glossary defines selected terms used in the text of this manual
which might be unfamiliar to some users or which might be used differently by
different authors.
Accidental release; The unintentional spilling, leaking, pumping, purging,
emitting, emptying, discharging, escaping, dumping, or disposing of a toxic
material into the environment in a manner that is not in compliance with a
plant's federal, state, or local ertvirorunenral pernitr and/or results in toxic
concentrations in the air that are a potential health threat to the
surrounding community.
Assessment: The process whereby the hazards which have been identified are
evaluated in order to provide an estimate for the level of risk.
Cavit at ion: The fornation and collapse of vapor bubbles in a flowing liquid.
Specifically the formation and c.'llapae of vapor cavities in a puap when there
19 sufficient resistance to flow ar th-» iilet aide.
Can? »'."i:?":,'conrrol; A syotea to which toxic emissions from safety telief
discharges are routed to be controlled. A caustic scrubber and/or flare can
be containment/control devices. These systems may serve the dual function of
destructing con,*, inuoup process exhaust gas emissions.
Creep failure; Failure of a piece of metal as a result of creep. Creep is
time dependent deformation as a result of stress. Metals will deform when
exposed to stress. High levels of stress can result in rapid deformation and
rapid failure. Lower levels of stress can result in slow deformation and
protracted failure.
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Deadheading: Closing or nearly closing or blocking the discharge outlet or
piping of an operating pump or compressor.
Facility: A location at which a process or set of processes are used to
produce, refine or repackage chemicals, or a location where a large enough
inventory of chemicals are stored so that a significant accidental release of
a toxic chemical is possible.
Hazard: A source of danger. The potential for death, injury or other forms
of damage to life and property.
Hygroscopic: Readily absorbing and retaining moisture, usually in reference
to readily absorbing moisture from the air.
Identification: The recognition of a situet-ior, its causes and consequences
relating to a defined potential, e.g. Hazard Identification.
Mild st?el: Carbon steel containing a maximum of about 0.252 carbon. Mild
steel is satisfactory for use where severe corrodants are not encountered or
where protective coatings can be sed to prevent or reduce corrosion rates to
acceptable levels.
Mit iRation; Any measure ta>ccri to reduce the severity of the advc: *> effects
associated with the accidental release of a hazardous chemical.
Passivation film: A layer of oxide or other chemical compound of a ir.etal on
its surface that acts as a protective barrier against corrosion or further
chemical reaction.
Plane: A location at which a process or set of processes are used to produce,
refine, or repackage, chemicals.
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Prevention: Design and operating measures applied to a process to ensure that
primary containment of toxic chemicals is maintained. Primary containment
means confinement of toxic chemicals within the equipment intended for normal
operating conditions.
Primary Containment; The containment provided by the piping, vessels and
machinery used in a facility for handling chemicalu under normal operating
conditions.
Probability/potential: A measure, either qualitative or quantitative, that an
event will occur within some unit of time.
Process: The sequence of physical and chemical oparations for the production,
refining, repackaging or storage of chemicals.
Process machinery: Process equipment, such as pumps, compressors, heaters, or
agitators, that would not be categorized as piping or vessels.
Protection: Measures taken to capture or destroy a toxic chemical >:nat has
breached primary containment, but before an uncontrolled release to the
environment has occurred.
Qualitative Evaluation: Assessing the risk of an accidental release at a
facility in relative terms; the end result of the assessment being a verbal
description of the risk.
Quantitative Evaluation: Assessing the risk of an accidental release at a
facility in numerical terms; the end result of the assessment- 1 .-mg aomo type
of nuaber reflects risk, such as faults per year or sop-, '.ime between failure.
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It.-activity: The ability of one cheaical to undergo a cheaical reaction with
another chemical. Reactivity of o " cneaical is always measured Lit reference
to the potential for reaction with itcelf or with another chemical. A cheaical
is sometimes said to bo "reactive", or have high "reactivity", witnout
reference to another cheoical. Usually this aeans that the chemical has the
ability to react wn.h tanmon materials such as water, or common materials of
construction such as carbon srevl.
Redundancy: For control systems, redundancy is the presence of a second piece
of control equipment where only one would be required. The second piece of
equipment is installed to act as a backup in the event that the primary piece
of equipaett fails. Redundant equipment can be installed to back-up all or
selected portions of a control system.
Risk: The probability that a hazard nay bo realized at any specified level in
a given span of time.
Secondary Containment: Proces3 equipaent specifically designed to contain
material that has breached primacy containment before the material is released
to cite environment and becomes an accidental release. A vent duct and
scrubber that are attached to the outlet of a pressure relief device arc
examples of secondary containment.
Toxicity *. A measure of the adverse health effects of exposure to a chemical.
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APPENDIX B
TABLE B-l. METRIC (SI) CONVERSION FACTOKS
Quantity
To Convert Froa
To
Length:
Area:
Voluae:
MaEO (weight):
Precoure:
Temperature:
Caloric Value;
Enthalpy:
Specific-Heat
Capacity:
Density:
Concent rat ion:
Flovrate:
Velocity:
Viocoaity:
in
.f5
ft3
£
gal
lb
short ton (ton)
ehort ton (ton)
ato
em Hg
poio
psig
°F
°C
Btu/lb
Btu/lbnol
kcal/p.nol
Btu/lb-°F
lb/ft3
lb/gax
o:/gal
quartc/gal
Cnl/oin
gal/day
ft /air.
ft/min
ft/sec
centipoise (CP*
kPa*
00
K*
kJ/kE
kJ/kp,nol
kJ/kgjol
kJ/kg-°C
kg/n
k§^3
/n
n^/min
m^/day
d /min
a/min
n/oec
kg/m-a
Multiply By
CD
2.54
2
3.3048
co2
6.45'i6
°3
cn
0.0929
16.39
al
0.0263
m
0.0038
H
0.4536
Mg
0.9072
(t)
0.9072
kPa
101.3
kPa
0.133
kPa
6.895
(poig+14.696)x(6.895)
(5/9)*(°F-3 2)
°C«-27 3. 15
2.326
2.3 26
4. IE*
4.1668
16.02
119.P
25/ DO
0.' ,J0
O.i J3S
0.C 283
o.:o48
0.3048
0.001
'Calculate an indicated
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