PB87-234522 Prevention Reference Manual: Chemical Specific. Volume 7. Control of Accidental Releases of Chloropicrin (SCAQMD) (South Coast Air Quality Management District) Radian Corp., Austin, TX Prepared for Environmental Protection Agency Research Triangle Park, NC Aug 87 1 l UMMHW. U*wr 1 isaz V Sg^SEESBBBSS JWLUIMUiHIIMWl 1U&1 & Skssssse §3S3£^23 22X533 ew ------- CB87-234522 EPA/600/8-87/034g August 1987 PREVENTION REFERENCE MANUAL: CHEMICAL SPECIFIC VOLUME 7: CONTROL OF ACCIDENTAL RELEASES OF CHLOROPICRIN (SCAQMD) By: D.S. Davis G.B. DeWolf J.D. Quass Radian Corporation Austin, Texas 78720-1088 Contract No. 68-02-3889 Ta6k No. 98 EPA 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 ------- _ TECHNICAL REPORT DATA (Keate read icjo-jttium -on iht reriru befcst tosipttrtng} 1 SEPOHTWO. J. E PA/6C 0/8-87/034 q *W-a§T4T2 27S 4 TiTltANDSUSTITLl Prevention Reference Manual: Chemical Specific, Volume 7: Control of Accidental Releases of Chloropicrin (SCAQMD) fl. REPCai DATE August19B7 I. PERFORMING ORGANIZATION CODE 7. AUTHOR(S) D. S. Davis, G. B. DeWolf, and J. D. Quass 3. PERFORMING ORGANIZATION REPORT NO DCN 87-203-024-98-26 » PERFORMING ORGANIZATION NAME AND ADDRESS Radian Corporation 8501 Mo-Pac Boulevard Austin, Texas 78766 tO. PROGRAM EkEM^NV N&. 11. CONTRACT/GRAbf Nft. 68-02-3889, Task 98 13. SPONSORI NG AGENCY NAME AND ADDRESS EPA, Office of Research and Development Air and Energy Engineering Research Laboratory Research Triangle Park, NC 27711 IX TYPE OF REPORT AND PERIOD COVERED Task Final; 9/86 - 4/87 14. SPONSORING AGENCY CODE EPA/600A3 is.supptEMENTARVNOTEs ^eeRL project officer is T. Kelly Janes, Mail Drop 62B. 919/541- 2852. io. abstract xhe manual summarizes technical information that will assist in identifying and controlling chloropicrin-associated 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 re- lease of toxic chemicals. The strategy includes monitoring the storage, handling, and use of certain chemicals and providing guidance to industry and communities. Chloropicrin has an immediately dangerous to life and health (IDLH) concentra- tion of 1 ppm, making it a substantial acute toxic hazard.'To reduce the risks asso- ciated with an accidental release of chloropicrin, some of the potential causes of accidental releases that apply to processes that use chloropicrin in the SCAQMD must be identified. Examples of potential causes are identified, as are measures that may be taken to reduce the accidental release risk. Such measures include re- commendations on: plant design practices; prevention, protection, and mitigation technologies; and operation and maintenance practices. Conceptual costs of possible prevention, protection, and mitigation measures are estimated. IT. KEY WORDS AND DOCUMENT ANALYSIS L DESCRIPTORS b.lOENTIFIERS/OPEN ENDED TERMS c. cos ATI Fold/Croup Pollution Chlorohydrocarbons Emission Design Accidents Maintenance Toxicity Storage Pollution Control Stationary Sources Chloropicrin Accidental Releases 13 B 07 C 14G 13 L 06T 15E 1 8 DISTRIBUTION 5TAT£M£*T Release to Public IB SECURITY CLA5S fPuiReportJ Unclassified 21 NO. Of PAGES 84 20 SECURITY CLASS (T*M paftf Unclassified M PRICE CPA Form JJSfr-1 (*7J) t ------- 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 ------- ABSTRACT A strategy for reducing the risk of a major accidental air release of toxic chemicals has developed a strategy tor reducing the risk of a major accidental 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 summarizes technical information that will assist in identifying and controlling release hazards associated with chloropicrin specific to the SCAQMD. Chloropicrin £.as has an IDLH (Immediately Dangerous to Life and Health) concentration of 1 ppts, which makes it a substantial acute toxic hazard. To reduce the risks associated with an accidental release of chloropicrin, seme of the potential causes of accidental releases that apply to processes that use chloropicrin in the SCAQMD must be identified. 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. ------- 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 addi- tion, 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 prepar- ing 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 Robert J. Brouwer and others, special thanks are given to the matay other people, both in government and industry, who served on the Technical Advisory Group and as peer reviewers. iv ------- TABLE OF CONTENTS Section page ABSTRACT 1 i 1 ACKNOWLEDGEMENTS 1y FIGURES Vi TABLES VH Section Page 1 INTRODUCTION 1 1.1 Background 1 1.2 Purpose of This Manual 1 1.3 Use of Chloropicrin 2 1.4 Organization of the Manual 2 2 CHEMICAL CHARACTERISTICS 4 2.1 Physical Properties 4 2.2 Chemical Properties and Reactivity 6 2.3 Toxicological and Health Effects 6 3 FACILITY DESCRIPTIONS AND PROCESS HAZARDS 9 3.1 Processing 9 3.2 Storage and Transfer 11 3.3 Potential Causes of Releases 11 3.3.1 Process Causes 11 3.3.2 Equipment Causes 12 3.3.3 Operational Causes 12 4 HAZARD PREVENTION AND CONTROL 14 4.1 General Considerations 14 4.2 Process Design IS 4.3 Physical Plant Design 15 4.3.1 Equipment 17 4.3.2 Plant Siting and Layout 21 4.3.3 Transfer and Transport Facilities 22 4.4 Protection Technologies 23 4.4.1 Enclosures 23 4.4.2 Scrubbers ..... 24 4.5 Mitigation Technologies 26 4.5.1 Secondary Containment System 26 4.5.2 Flotation Devices and Foams 30 4.5.3 Mitigation Techniques for Chloropicrin Vapor . . 31 4.6 Operation and Maintenance Practices 33 4.7 Control Effectiveness 34 V ------- TABLE OF CONTENTS (Continued) Section Page 4.8 Illustrative Cost Estimates for Controls 34 4.8.1 Prevention and Protection Measures 36 4.8.2 Levels of Control 36 4.8.3 Cost Summaries ................. 38 4.8.4 Equipment Specifications and Detailed Costs - . . 44 4.8.5 Methodology 44 5 REFERENCES 69 APPENDIX A . GLOSSARY 71 APPENDIX B . METRIC (SI) CONVERSION FACTORS 75 FIGURES Number Page 3-1 Conceptual process diagram of a typical batch chloropicrin manufacturing process 10 vi ------- TABLES Number Pase 2-1 Physical Properties of Chloropicrin 5 2-2 Exposure Limits for Chloropicrin 7 2-3 Predicted Human Health Effects of Exposure to Various Concentrations of Chloropicrin 8 4-1 Key Process Design Considerations and Processes Involving Chloropicrin 16 4—2 Examples of Major Prevention and Protection 'feasures for Chloropicrin Releases 35 4—3 Estimated Typical Costs of Some Prevention and Protection Measures for Chloropicrin Releases 37 4-4 Summary Cost Estimates of Potential Levels of Controls for Chloropicrin Storage Tank and Batch Reactor 39 4-5 Example of Levels of Controls for Chloropicrin Storage Tank ... 40 4-6 Example of Levels of Controls for Chloropicrin Manufacture ... 42 4-7 Estimated Typical Capital and Annual Costs Associated with Baseline Chloropicrin Storage System 45 4-8 Estimated Typical Capital and Annual Costs Associated with Level 1 Chloropicrin Storage System 46 4-9 Estimated Typical Capital and Annual Costs Associated with Level 2 Chloropicrin Storage System 47 4-10 Estimated Typical Capital and Annual Costs Associated with Baseline Continuous Chloropicrin Production 48 4-11 Estimated Typical Capital and Annual Costs Associated with Level 1 Continuous Chloropicrin Production 49 4-12 Estimated Typical Capital and Annual Costs Associated with Level 2 Continuous Chloropicrin Manufacture 50 4-13 Equipment Specifications Associated with Chloropicrin Storage System 51 vii ------- TABLES (Continued) Number Page 4-14 Material and Labor Coats Associated with Baseline Chloropicrin Storage SyGttts 53 4-15 Material and Labor Costs Associated with Level 1 Chloropicrin Storage System . . . . .......... 54 4-16 Material and Labor Costs Associated with Level 2 Chloropicrin Storage System . . . 55 4-17 Equipment Specifications Associated with Chloropicrin Manufacture 56 4-18 Material and Labor Costs Associated with Baseline Continuous Chloropicrin Production 5fl 4-19 Material and Labor Coats Associated with Level 1 Continuous Chloropicrin Production .............. 59 4-20 Material and Labor Costs Associated with Level 2 Continuous Chloropicrin Production .......... ...... 60 4-21 Format for Total Fixed Capital Cost 61 4-22 Format for Total Annual Cost 63 4-23 Format for Installation Costs ....... 68 viii ------- SECTION 1 INTRODUCTION 1.1 BACKGROUND Recognizing the potential risk associated with accidental releases of air toxics in southern California, the South Coast Air quality Management District (SCAQMD). conducted a study in 1985 to determine the presence, quantities, and uses of hazardous chemicals in the SCAQMD, which includes Los Angeles, Orange, San Bemadino, and Riverside Counties. 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. The strategy includes monitoring industry activities associated with storing, handling, and using certain chemicals; using the best technical information available; and guiding industry and communities in reducing the potential for accidental releases and the consequences of any releases that might occur. Historically, it appears there have been no significant releases of chloropicrin in the SCAQMD. Major incidents elsewhere involving chloropicrin have not been common. 1.2 PURPOSE OF THIS MANUAL This manual compiles technical information on chloropicrin, specifically on preventing accidental releases of chloropicrin. The manual addresses technological and procedural issues associated with storing, handling, and processing chloropicrin as it is used in the SCAQMD. 1 ------- This manual is not a specification manual, and in fact refers the reader to technical manuals and other sources for more complete information on the topics discussed. Other sources include manufacturers and distributors of chloropicrin, and technical literature on design, operation, and loss preven- tion in facilities handling toxic chemicals. 1.3 USE OF CHLOROPICRIN Chloropicrin (CCl^NO^) is manufactured commercially from bleaching powder and picric acid or by the chlorination of nitromethane in the presence of caustic. It is used primarily as an insecticide, as a soil fumigant, and as a warning agent in commercial fumigants. It is also used as a chemical interme- diate in the organic synthesis of dyes, as a chemical sterilant, and as a nauseant in chemical warfare. Numerous references in the technical literature describe the canufacture and uses of chloropicrin. Limited survey date indicate that in the SCAQMD, chloropicrin is manufactured from nitromethane and sodium hypochlorite at one site (1). Approximately 10-150 tons of chloro- picrin are maintained at this site at any time (1). The chloropicrin is used in the formulation of chloropicrin-methyl bromide mixtures and is shipped to contract fuaigators or re-formulators for further use (1). Storage of chloropicrin appears to be limited to small cylinders (e.g., 150 lb.) and bulk, storage tanks. 1.4 ORGANIZATION OF THE MANUAL Following the introductory section, the remainder of the manual presents technical information on specific hazards and categcries of hazards and their control as they relate to chloropicrin. Section 2 discusses physical and chemical properties. Section 3 de- scribes the types of facilities whets chloropicrin is used in the SGAQMD and process hazards found in those facilities. Hazard prevention and control are discussed in Section A, as are costs of example storage and process 2 ------- facilities, reflecting different levels of control through alternative systems. The examples are for illustration only and do not necessarily represent a satisfactory alternative control option in all cases. Section 5 conrains 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 ------- SECTION 2 CHEMICAL CHARACTERISTICS This section of the manual describes the physical, chemical and toxico- logical properties of chloropicrin as they relate to accidental release hazards. 2.1 PHYSICAL PROPERTIES At rooo temperature and pressure, chloropicrin is a colorless, oily liquid with a sharp penetrating odor. Some of its common physical properties are shown in Table 2-1. Chloropicrin is only slightly soluble in water. It is, however, partial- ly soluble in ether, and niscible in benzene, carbon disulfide, and amyl alcohol. In addition, chloropicrin is more dense than water and large spills in water may settle before being totally dispersed or volatilized. Because it has a relatively high evaporation rate, spills and leaks of chloropicrin can result in hazardous air releases. In addition, since the density of chloropicrin vapor is greater than that of air, it will remain close to the ground, potentially creating a dangerous situation for workers and surrounding communities. Chloropicrin has a moderately large coefficient of expansion, expanding approximately 5 percent when warmed from 68°F to 1A0°F (2). Consequently, liquid-full equipment presents a special hazard. A liquid-full vessel is a vessel that is not vented and has little or no vapor space above the liquid. A liquid-full line is a section of pipe sealed off at both ends and full of liquid, with little or no vapor space. In such cases, there is no room for thermal expansion of the liquid and temperature increases can result in containment failure. A ------- TABLE 2-1. PHYSICAL PROPERTIES OF CHLOROPICRIN Reference CAS Registry Number Chemical Formula Molecular Height Normal Boiling Point Melting Point Liquid Specific Gravity (tUO^) Vapor Specific Gravity (air=l) Vapor Pressure Vapor Pressure Equation:* log Pv where: 76-06-2 Ca3N°2 164. 4 233.6 °F 6 I ata -83.2 °F 1.651 e 68 °F 5.7 0 233.6°F 0.35 psia 8 68°F B = A - Solubility in Uater Specific Heat at Constant Pressure Latent Heat of Vaporization Liquid Surface Tension Average Coefficient of Thermal Expansion, 32 °F - 158 °F T+C Pv = vapor pressure, mmHg T = temperature, °C A = 7.7911, a constant B = 1,823.90, a constant C = 259.44, a constant 0.12 lb/ft3 0.225 Btu/(lb-°F) 99.9 Btu/lb 32.3 dyn/cm © 68°F 0.00116/°F 2 2 3 3 2 4 3 2 2 2 2 ~Constants were calculated using formula derived in Reference 4 and vapor pressure data from Reference 2. 5 ------- 2.2 CHEMICAL PROPERTIES AMD REACTIVITY The most significant propertieo contributing to a potential accidental release of chloropicrin are: • Chloropicrin decomposes violently when heated above its normal boiling point of 233.6°F. to severely toxic gases, including nitric oxide, phosgene, nitrosy1 chloride, chlorine, and carbon monoxide. The rate of decomposition is increased by contact with metal6 (2,5). « Most metals are corroded or tarnished to some degree by chloropicrin. In particular, since chloropicrin severely corrodes sluminum. magnesium and their alloys under certain conditions, they should not be used in chloro- picrin service (2). • Chloropicrin is incompatible with strong oxidizers and contact can result in the formation of flammable and explosive gaseous mixtures (6). During the process and storage of chloropicrin such conditions should be avoided. 2.3 TOXICOLOGICAL AND HEALTH EFFECTS The toxicological effects of chloropicrin have been well-documented (7). Chloropicrin is s severe irritsnt to the eyes, skin, and respiratory tract. Exposure results in lachrymation. coughing, nausea, vomiting, bronchitis, and pulmonary edema (6.8.9). An additional toxic effect is that it interferes with oxygen transport by reacting with SH-groupe in hemoglobin (8). Vomiting occurs after swallowing saliva in which small amounts of chloropicrin have dissolved. Table 2-2 summarizes some of the relevant exposure limits for 6 ------- chloropicrin. Table 2-3 summarizes the predicted human health effects of exposure to various concentrations of chloropicrin. TABLE 2-2. EXPOSURE LIMITS FOR CHLOROPICRIN Exposure Limit Concentration (ppm) Description Reference IDLH PEL TCLo LCLo 4 The concentration defined as posing an immediate danger to life and health (i.e., causes irreversible toxic effects for a 30-minute exposure) 0.1 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. 0.3 This concentration is the lowest pub- lished concentration causing toxic effects (irritation) for a 1-minute exposure. 119 Thi6 concentration is the lowest pub- lished lethal concentration for a human over a 30-ainute exposure. 10 10 7 ------- TABLE 2-3. PREDICTED HUMAN HEALTH EFFECTS OF EXPOSURE TO VARIOUS CONCENTRATIONS OF CHLOROPICRIN ppm Predicted Effect 0.3 - 0.37 Painful eye irritation results in 3 to 30 seconds 1.1 Odor threshold 4 Temporarily disabling as a result of irritant effects after a fev seconds 15 Intolerable longer than 1 minute 20 Causes bronchial or pulmonary lesions after 1 to 2 minutes 119 Death resulting from pulmonary edeca after 30 minutes 8 ------- SECTION 3 FACILITY DESCRIPTIONS AND PROCESS HAZARDS This section briefly describes the uses of chloropicrin in the SCAQMD and highlights major process hazards related tc accidental releases. Preventive measures associated with these hazards are discussed in Section 4. 3.1 PROCESSING According to the survey data, chloropicrin is manufactured in the SCAQMD by the chlorination of nitronethane and is used to make chloropicrin-methyl bromide mixtures. This section summarizes the major technical features of typical processing and storage facilities that might be found in the SCAQMD and discusses the associated accidental releace hazards. Chloropicrin is manufactured by batch chlorination of nitromethane. Figure 3-1 presents a typical chlorination system. The process consists of adding over a given period of time a slight excess of nitromethane to an aqueous solution of sodium hypochlorite in a stirred, uncooled batch reactor (9,11). To prevent boiling of the reaction mixture the temperature of the reactor contents is maintained belov 165°F by controlling the temperature and concentration of the sodium hypochlorite used. The primary hazard associated with the manufacture of chloropicrin is the exothermic nature of the chlorination reaction. The potential exists for a runaway reaction, resulting in overheating and overpressure. Adequate temper- ature control and agitation are required to prevent a hazardous release of toxic material. 9 ------- WATER -fe NITROMETHANE STORAGE SODIUM HYPOCHLORITE i. STORAGE ^ n a&O BATCH CHL0R1NATI0N REACTOR CHLOROPICRIN STORAGE 3 Figure 3-1. Conceptual process diagram of a typical batch chloropicrin aanufacturing process. ------- 3.2 STORAGE AND TRANSFER Chloropicrin is stored in low-pressure storage vessels to prevent vapor loss (12,13). Because of the acute toxicity of cfaloropicrin vapor, a sealed vessel is typically used to prevent breathing loss emissions. Transfer of chloropicrin involves a closed system (12). Vapor exchange to a tank truck is commonly used when filling a chloropicrin storage tank. The system consists of a pipeline between the vapor spaces of the tank truck and the storage vessel. The vapors can then be displaced from the receiving tank and transported back to the loading terminal. When emptying a chloropicrin storage tank, nitrogen replaces the chloropicrin vapors in the vapor space. 3.3 POTENTIAL CAUSES OF RELEASES Chloropicrin releases can originate from many sources, including leaks or ruptures in vessels, piping, valves, instrumentation connections, and process machinery such as pumps. Failures leading to accidental releases may be broadly classified as due to process, equipment, or operational problems. The causes of releases discussed below are illustrative and do not exhaust all possibilities. 3.3.1 Process Causes Process causes are related to the fundamentals of process chemistry, control, and general operation. Possible process causes of a chloropicrin release include: • Excess nitroaetbane feed to a batch reactor leading to excessive exothermic reaction; Li ------- • Excess feeds in any part of tbe system leading to over- filling or overpressuring equipment; • Overpressure in chloropicrin storage vessels. This situation may be caused by heat generated by a reaction of chloropicrin with contaminants, fire exposure, or unre- lieved overfilling. 3.3.2 Equipment Causes Equipment causes of accidental releases result from hardware failures. Possible causes include: • Excessive stress due to Improper fabrication, construc- tions, or installation; • Failure of a vessel due to weakening of equipment from excessive stress, external loadings or corrosion; and • Pipe or pump failure due to excessive stress, external loading, erosion or corrosion. 3.3.3 Operational Causes Operational causes of accidental releases are a result of incorrect operating and maintenance procedures or human operating errors. These causes include: • Overfilled storage vessels; • Improper process system operation; • Errors in chloropicrin transfer procedures; 12 ------- Inadequate maintenance in general, but especially of pressure relief systems and other preventive and protec- tive systems; and Lack of inspection and non-destructive testing of vessels and piping to detect corrosion weakening. 13 ------- SECTION 4 HAZARD PREVENTION AND CONTROL 4.1 GENERAL CONSIDERATIONS The prevention of accidental releases relies on a combination of techno- logical. administrative, and operational practices that apply to the design, construction, and operation of facilities where chloropicrin is manufactured, stored and used. Considerations in these areas can be grouped as follows: • Process design; • Physical plant design; o Operating and maintenance practices; and • Protective systems. In each of these areas, specific factors must be considered that could lead to a process upset or failure that could directly cause a release of chloropicrin to the environment or result in an equipment failure that would then cause the release. At a minimum, equipment and procedures should be examined to ensure they are in accordance with applicable codes, standards, and regulations. In addition, stricter equipment and procedural specifica- tions should be used if extra protection against a release is considered appropriate. The following subsections discuss specific considerations regarding release prevention; more detailed discussions will be found in the manual on control technologies. 14 ------- 4.2 PROCESS DESIGN Process design involves the fundamental characteristics of the process by which chloropicrin is manufactured. 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 resulting 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. Quan- tity measuring systems, mixing systems, fire protection, and process control instrumentation may also be considered. Modifications tc enhance process integrity would involve changes in quantities of materials, in process pres- sure and temperature conditions, in unit operations and sequence of opera- tions, in process control strategies, and in the instrumentation used. Table 4-1 shows the relationship between key process design considera- tions and the individual processes described in Section 3 of this manual. This does not mean that other factors should be ignored, nor that proper attention to the key consideration ensures a safe system. These considera- tions must be properly addressed, however, to ensure a safe system. The primary consideratior in the manufacture of chloropicrin ia pre- venting overheating and boiling of the batch reactor contents that might lead to overpressure. Equipment failure without overpressure is also possible if corrosion has weakened process equipment. 4.3 PHYSICAL PLANT DESIGN Physical plant design involves equipment, siting and layout, and trans- fer/transport facilities. Vessels, piping and valve, process machinery, instrumentation, and factors such as location of systems and equipaent must all be considered. The following subsections cover various aspects of physi- cal plant design, beginning with a discussion of materials of construction. 15 ------- TABLE 4-1. KEY PROCESS DESIGN CONSIDERATIONS AND PROCESSES INVOLVING CHLOROPICRIN Process Design Consideration Process or Unit Operation Flov control of feed streams Temperature monitoring Adequate pressure relief Mixing Corrosion monitoring Level sensing and control Batch chloropicrin reactor Batch chloropicrin reactor Storage tanks and batch chloropicrin reactor Batch chloropicrin reactor Storage tanks and batch chloropicrin reactor Storage tanks <»nd batch chloropicrin reactor 16 ------- A.3.1 Equipment Materials of Construction— Practically all netals are corroded or tarnished by chloropicrin, but not enough to prevent their use as construction materials (2). In addition, metals tend to catalyze the decomposition of chloropicrin (2). Chloropicrin can be stored in a mild steel shell at 1A0°F for 15 veeks with only a minimum amount of decomposition (2). Although chloropicrin attacks the shell, the degree of corrosion is minimal. It can likewise be stored at room temperature for at least one year with no pronounced changes other than slight corrosion of the shell (2). Other materials more resistant to the corrosiveness of chloropicrin are the stainless steels, titanium, and nickel-copper and nickel-chromiua-nolyb- denum alloys. However, stainless steel tends to concentration cell corrode (1A). This type of corrosion results from a difference in the amount of oxygen in solution at one point as compared with another (15). Corrosion is accelerated where the oxygen concentration is least. This occurs in a stuf- fing box or under gaskets, for example. Equipment used in chloropicrin service is commonly lined with tetra- fluoropolyethylene, vinylidene chloride, or pclyvinylidene fluoride to prevent corrosion (1A). Polypropylene resins and polyvinyl chloride are not recom- mended (1A). Aluminum, magnesium and their alloys should not be used in chloropicrin service since chloropicrin can react violently with these materials (5). Vessels— Low pressure storage tanks and batch reactors are used in chloropicrin service (13). Each type of vessel has certain design and fabrication specifi- cations under various codes and standards that should be adhered to. 17 ------- Chloropicrin shipping containers must meet Department of Transportation (DOT) specifications. Although exact specifications for batch reactors used in the manufacture of chloropicrin are unavailable, they should at least conform to applicable codes for low-pressure vessels. Specific release prevention considerations for vessels include over- pressure protection, temperature control, and corrosion prevention. Process vestels are usually protected by pressure relief valves and/or rupture discs. The pressure relief valve is set to relieve slightly above the design working pressure of the vessel, but veil below the maximum allowable working pressure. Pressure relief valves and rupture discs are designed to prevent explo- sion by allowing a controlled release of overpressurized contents. These relief systems are usually sized for flashing liquid caused by (16): • Fire exposure: • Thermal expansion; • Internal reaction/decomposition; and • Excess supply rates. Relief piping must be sized for adequate flow. Preventing a relief discharge to the environment requires that the discharge be handled through one of the protection systems discussed in Section 4.4 of this manual. Piping— Ab with chloropicrin vessels, chloropicrin pipework design must reflect the pressure, temperature, and corrosion associated with use of the chemical. Careful attention must be paid to pipework and associated fittings since failures of this type of equipment are major contributors to accidental 18 ------- releases of chemicals (16). Ac for all toxic chemicals, there are general guidelines for chloropicrin piping systems (16). The first is simplicity of design; the number of joints and connections should be minimized. In addition to being securely supported, pipes should be sloped, with drainage at the low points. Piping should be constructed to allow room for thermal expansion of the pipe and should be protected froas exposure to fire and high temperatures. Placement of valves should ensure isolation of leaking pipes and equipment. The correct design and use of pipe supports is essential to reducing 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. Thermal expansion and contraction, vibrations caused by pumping and fluid flow, bending movements resulting from overpressure in the pipe, and external loads 6uch as winds or ice accumulation must all be considered. All piping should be situated away from fire and fire hazards since chloropicrin can explode violently above its boiling point (2).. If possible, piping carrying chloropicrin 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). Pipe flanges should be situated to minimize potential hazards from drips and small leaks-. In addi- tion, the piping network should be protected from possible impact and other structural damage. Valves in chloropicrin service include gate, globe, ball, relief, and check configurations; they must be constructed of materials suitable for chloropicrin service. Check valves, which are a primary means of preventing uodesired back or reverse flows, can prevent undesired materials from entering chloropicrin-containing equipment and possible explosive reactions resulting from backups into tanks. Check valves are also used widely on the puap discharges to prevent backflow that could render a pump inoperable and even- tually result in a hazardous release. 19 ------- Process Machinery— Process machinery is rotating or reciprocating equipment that may be used for transferring or processing chloropicrin. Pumps—Centrifugal, rotary, positive displacement, and sealless pumps are used to puap chloropicrin. To ensure that a given pump is suitable for chloropicrin service, the system designer should obtain information from the pump manufacturer certifying that the pump will perform properly in this application. Pumps should be constructed of materials resistant to chloropicrin 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; the pump should be interlccked to shut off at low supply level or low discharge pressure. External pumps should be situated inside a diked area, and they should be accessible in the event of a tank leak. In some situations, the potential for seal leakage rules out the use of rotating shaft seals. Pump types that either isolate the seals from the process stream, or eliminate them altogether include canned-motor pumps, vertical extended-spindle submersible pumps, magnetically coupled pumps and diaphragm pumps (15,16). Canned motor pumps are centrifugal units in which the motor housing is interconnected with the punp casing. Here, the process liquid actually serves as the bearing lubricant. An alternative concept is the vertical pump often used on storage tanks. These pumps consist of a submerged impeller housing connected by an extended drive shaft to the motor. The advantages are that the shaft seal is above the maximum liquid level (and is therefore not wetted by the pumped liquid) and the pump is 6elf priming because the liquid level is above the impeller. 20 ------- Hagnetically-coupled pumps replace the drive shaft with a rotating magnetic field as the pump-motor coupling device. Diaphragm pumps are positive displacement units in which a reciprocating flexible diaphragm drives the fluid. This arrangement eliminates exposure of packing and aeals to the pumped liquid; however, at some point, the diaphragm will probably fail and such a failure could lead to a release. These pumps usually have a pressure relief valve on the outlet, bypassing to the suction. Improper operation of pumps, i.e., running dry and deadheading, can damage and cause failure of puaps. Running a pump dry because of loss of head in a feed tank, for -example, can seriously damage a pump. Pumping against a closed valve can also have serious ramifications, causing a temperature rise of the liquid within the pump. This heating could result in therual decomposi- tion of the chloropicrin within the pump, which could lead to an accidental release. Such an occurrence may be avoided with a pump bypass or kick-back loop. Failure of a pump, for whatever reason, can eventually lead to a hazardous release. 6.3.2 Plant Siting and Layout The siting and layout of a chloropicrin facility requires careful consid- eration of numerous factors, including: other processes in the area, the proximity of population centers, prevailing winds, local terrain, and poten- tial natural external effects such aa flooding. The siting of facilities or individual equipment items should reduce personnel exposure, both plant and public, in the event of a release. Since other siting considerations are also important, there may be trade-offs between this requirement and other safety-related requirements in a process. Siting should allow ready ingress or egress in the event of an emergency and yet also take advantage of barriers, either man-made or natural, that could reduce the consequences of a release. 21 ------- Various techniques available for formally assessing a plant layout should be considered when planning high haiard facilities (16). General layout considerations include: • Large inventories of chloropicrin Bhould be kept away frou sources of fire or explosion hazard; • Vehicular traffic should not go too near chloropicrin manufacture or storage areas if it can be avoided; • Where such traffic is necessary, precautions should bs taken to reduce the chances of vehicular collisions with equipment, especially pipe racks carrying chloropicrin across or next to roadways; and • 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. 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 design the drainage of a diked area to an underground containment sump. 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 22 ------- the intermittent nature of the operations. Special attention should be given to the design of these facilities. Tank car and tank truck facilities should be located away fron sources of baat, fire, and explosion. Equipment in these areas should also be protected from impact by vehicles and other moving equipment. Tank vehicles should be securely moored during transfer operations; an interlocked barrier system is commonly used. Sufficient space should be available to avoid congestion of vehicles or personnel during loading and unloading operations. Vehicles, especially truckst should be able to move into and out of the area without reversing. High curbs around transfer areas and barriers around equipment should be provided to protect equipment from vehicle collisions. 4.A PROTECTION TECHNOLOGIES This section describes two types of protection technologies for contain- ment and neutralization: © Enclosures, and • Scrubbers. 4.4.1 Enclosures Enclosures refer to containment structures that capture any chloropicrin 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, discharged at a controlled rate that would not be injurious to people or to the environment, or transferred at a controlled rate to scrubbers for neutralization. The location of toxic operations in the open air has been favorably mentioned in the literature (16), but so has the opposing idea that sometimes 23 ------- enclosure may be appropriate. The practicability of using an enclosure depends partly on how often personnel must be involved with the equipment. A common design rationale for not having an enclosure where toxic materials are used is to prevent the accumulation of toxic concentrations within enclosed areas. However, if the issue is protecting the community from accidental releases, then total enclosure may be appropriate. Enclosures should be equipped with continuous monitoring equipment and alarms. Alarms should sound whenever lethal or flammable concentrations are detected. Care oust be taken when a enclosure is built around pressurized equip- ment. It would not be practical to design an enclosure to withstand the pressures associated with the sudden release of a pressurized vessel. An enclosure would probably fail from the pressure created from such a release, creating an additional hazard. In these situations, an enclosure may not be appropriate. If an enclosure is built around pressurized equipment, it should be equipped with 6ome type of explosion protection, such as rupture plates designed to fail before the entire structure fails. The type of structures that appear to be suitable for chloropicrin 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 scrubber. The bottom section of the building used for stationary storage containers should be liquid tight to retain any chloropicrin that might be spilled. A.A.2 Scrubbers Scrubbers, which are a traditional method for absorbing toxic gases from process streams, can be used for controlling chloropicrin releases from vents and pressure relief discharges, from process equipment, or from secondary containment enclosures. 24 ------- Chloropicrin discharges could be contacted vith an aqueous scrubbing medium in any of several types of scrubbing devices. An alkaline solution is needed to achieve effective absorption because absorption rates with water alone would require unreasonably hign liquid-to-gas ratios. A typical alka- line solution for an emergency scrubber is calcium hydroxide derived from slaked lime. Types of scrubbers that might be appropriate include spray towers, pecked bed scrubbers, and Venturis. Other special designs might be suitable, but complex internals subject to corrosion do not seem appropriate. Whatever type of scrubber is selected, a complete system would include the scrubber itself, a liquid feed system, and reagent makeup equipment. If such a system is used as protection against emergency relesses. one oust consider how it would be activated in time to respond to an emergency load. In some process facilities, a continuous circulation of scrubbing liquor is maintained through the system. For many facilities this would not be practi- cal. and the scrubber system might be tied into a trip system that turns it on when needed. Venturi scrubbers have an advantage when the scrubbing system is acti- vated by a trip system. A venturi scrubber can create its own draw of vapor by the flow of the scrubbing medium, so that the trip system need only turn on the flow of liquid to the scrubber, rather than turn on the flow of liquid and start up a blower, as would be required by alternate types of scrubbing systems. Another approach is the drowning tcwer where the chloropicrin vent is routed to the bottom of a large tank of uncirculating caustic. The drowning tower does not have the high contact efficiency of the other types, but can provide substantial capacity on demand as long as the back pressure of the hydrostatic head does not create a secondary hazard, by impeding an over- pressure relief discharge, for example. 25 ------- 4.5 MITIGATION TECHNOLOGIES If. in spite of all precautions, a large release of chloropicrin occurs, 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 this is possible. The next primary concern is to reduce the effects of the re- leased chemical 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 technique is to divert, limit, or disperse a chemical that has been spilled or released to the atmosphere to reduce the atmospheric concen- tration and the affected area. In addition, secondary containment systems such as impounding basins, dikes, and flotation devices and/or foams 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: its flammability, toxicity, reactivity, and those properties that determine its dispersion characteristics in the atmosphere. A post-release mitigation effort requires that the source of the release be accessible to trained plant personnel. Therefore, the availability of adequate personnel protection is essential. Personnel protection typically includes such items as portable breathing air and chemically resistant protec- tive clothing. A.5.1 Secondary Containment Systems 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 will depend on the risk associated with an accidental release from that location. The inventory of chloropicrin and its proximity to other 26 ------- portions of the plant and to the community should be considered when selecting a secondary containment system. The secondary containment system should have the ability to contain spills with a minimum of damage to the facility and its surroundings and with minimun potential for escalation of the event. Secondary containment systems for chloropicrin storage facilities common- ly consist of one of the following: o An adequate drainage system underlying the storage vessels that terminates in an impounding basin whose capacity is as large as that of the largest rank served; o A diked area whose capacity is as large as that of the largest tank served. These measures are designed to prevent the accidental discharge of chloro- picrin from spreading to uncontrolled areas. 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 increased risk. Dike heights usually range from three to twelve feet. 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. Dike walls must be constructed and maintained to prevent leakage through the dike. Piping should be routed over dike walls, and penetrations through the walls should be avoided if possible. Vapor fences may be situated on top of the dikes to provide adequate vapor storage capacity. If there is more than one tank in the diked area, the tanks should be situated on berms above the maximum liquid level attainable in the impoundment. A low-wall dike can effectively contain the liquid portion of an acciden- tal release and keep the liquid frcsi entering uncontrolled areas. By 27 ------- preventing the liquid from spreading, the low-wall dike can also reduce tbe surface area of the spill; reducing the surface area reduces tbe rate of evaporation. The lew-wall dike will partially protect the spill frcn wind, which can also reduce the rate of evaporation. A dike with a vapor fence will provide extra protection from wind and will be even more effective at reducing the rate of evaporation. A remote impounding basin is well-suited to storage systems serving more than one tank where a relatively large site is available. The flow frem a chloropicrin spill is directed to the basin by dikes and channels under tbe storage tanks; the channels are designed to minimize exposure of tbe liquid to other tanks and surrounding facilities. Because chloropicrin 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 tbe rate of evapora- tion. Also, the impounding basin should be located near the tank to minimize the amount of chloropicrin that evaporates as it travels to the basin. This type of system has several advantages. Tbe spilled liquid is 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 tay be the best 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 for the tank to be protected from external hazards. Kaximum 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 ares. 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- temperature steel, reinforced concrete, or prestressed concrete. A weather shield may be provided between the tank and wall with the annular space 28 ------- 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 the tank for containing vapors. Increasing the height of the wall also raises the elevation of any released vapor. One disadvantage of these dikes is 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 inspections and maintenance. As with low vail dikes, piping should be routed over the wall if possible. The closeness of the wall to the tank may require that the pump be pieced outside the wall, in which case the outlet (suction) line will have to pass through the wall. In such a situation, a low dike encompassing the pipe penetration and pump may be provided, or a low dike may be placed around the entire wall. A further type of secondary containment system is structurally integrated with the primary system to form a vapor-tight enclosure around the primary container. Many arrangements are possible. A double-walled tank is an example of 6uch an enclosure. These systems may be cons-'dered when protecting the primary container and containing vapor for events not involving foundation or wall penetration failure are of greatest concern. The drawbacks of an integrated system are the greater complexity of the structure, the difficulty of access to certain components, and the fact that complete vapor containment cannot be guaranteed. The ground within an enclosure should be graded so that the spilled liquid can accumulate at one side or in one corner. This will help minimize the area 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 inculation may be used in the diked area or impoundment to further reduce heat transfer from the environment to the spilled liquid. The floor of an 29 ------- impoundment may be sealed with a clay blanket to prevent the chloropicrin from seeping into the ground. A.5.2 Flotation Devices and Foams A common technique for reducing the hazards associated with a chloro- picrin spill is to spread soda ash on the spill, dilute with water,-and allow the mixture to stand for several hour6 (5) . The chloropicrin slowly reacts with the soda ash to form products that can be neutralized with a dilute acidic solution and disposed of. Other possible ways of reducing the surface area of spilled chemicals include placing impermeable flotation devices on the surface and applying foacs. Placing an impermeable flotation device over a spilled chemical is a direct and efficient way of containing toxic vapors. However, being able to use such devices requires acquisition in advance of a spill and storage until needed, and in all but small spills deployment may be difficult. In addition, material end dispersal equipment costs, are a major deterrent to their use (17). The use of foams in vapor hazard control has been demonstrated for a broad range of volatile chemicals. Unfortunately, it ie difficult to accu- rately 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. With some materials, foams have a net positive effect, but with others foams may exaggerate the hazard (17). Little or no information is available concerning the success of foam systems in controlling hazardous chloropicrin releases. However, based on research on chemicals similar in nature to chloropicrin, a net positive effect would be expected (17). The extent of the reduction in concentration for 30 ------- chloropicrin will ' r :nd on the type of foam used. Research in this area has indicated that foai /ith a mediiB to high expansion ratio (300 to 350:1) give significantly bett results than do foams with low expansion ratios (6 to 8:1) (17). 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 slow draining foam will spread more evenly, show more resistance to temperature and pH effects, and collapse more slowly. The initial cost of a slow-draining foam may be higher than for other foams, but a cost-effective system will be realized in superior performance. 4.5.3 Mitigation Techniques for Chloropicrin Vapor The extent to which the escaped chloropicrin vapor can be quickly removed or dispersed will be a function of the quantity of vapor released, the ambient conditions, and the physical characteristics of the vapor cloud. The behavior and characteristics of the chloropicrin cloud will depend on a number of factors, including the physical state of the chloropicrin before its release, the location of the release, and the atmospheric and environmental conditions. Many possibilities exist concerning the shape and motion of the vapor cloud, and a number of predictive models of dispersion have been developed. Because of the higher specific gravity of pure chloropicrin, large accidental releases of this chemical will often lead to the formation of chloropicrin-air mixtures that are more dense than the surrounding atmosphere. This type of vapor cloud is especially hazardous, because it will spread laterally and remain close to the ground. One means of dispersing and removing toxic vapor from the air is with water sprays or fogs. However, to be effective, an unpractically large volume of water would have to be used since chloropicrin has a low solubility in water. An alternative is to use a mild aqueous alkaline spray system such as an ammonia-injected water spray system that would neutralize the acid. 31 ------- The dispersing medium is commonly applied to the vepor cloud with hand-held hoses and/or stationary spray barriers. For effective absorption, it is important to direct foe or spray nozzles from a downwind direction to avoid driving the vapors downwind more quickly. Other important factors relating to the effectiveness of alkaline sprays are the distance of the nozzles from the point of release, the fog pattern, nozzle flow rate, pres- sure, and nozzle rotation. If the right strategy is followed, a "capture zone" can be created downwind of the release into which the chloropicrin vapor will drift and be absorbed. In low-wind conditions, two fog nozzles should be placed upwind of the release to ensure that the chloropicrin cloud keeps moving downwind against the fog nozzle pressures. Spray barriers consist of a series of spray nozzles that can be directed either up or dcwn. The&e barriers can be placed downwind of the source to absorb some of the chloropicrin vapors passing through without major distor- tion of the chloropicrin cloud (17). Several fog nozzles may be situated farther downwind to absorb additional vapors getting through. Another way of dispersing a vapor cloud is to use large fans or blowers that direct the vapor away irom populated or other sensitive areas (13). However, this method would only be feasible in very calm weather and in sheltered areas; it would not be effective in any wind and would be difficult to control if the release occupied a large open area. A large, mechanical blower would also be required, which decreases the reliability of this mitiga- tion technique. In general, techniques used to disperse or control vapor emissions should be simple and reliable. In addition to the mitigation techniques discussed above, physical barriers such as buildings and rows of trees can help contain the vapor cloud and control its movement. Hence, reducing the consequences of a hazardous vapor cloud can actually begin with a carefully planned la>jut of facilities. 32 ------- 4.6 OPERATION AND MAINTENANCE PRACTICES Accidental release of toxic materials result not only from deficiencies of design but also from deficiencies of operation. Thus safe operation of plants using chloropicrin requires competent and experienced managers and staff, in addition to a well considered and fully understood system of work. Employees should be trained about the important aspects of handling chloropicrin, including: the proper way to handle and store the chemical, hazards resulting from improper use and handling, prevention of 6pills, cleanup procedures, maintenance procedures and emergency procedures. Well- defined practices and procedures can decrease 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 chloro- picrin. Maintenance practices for chloropicrin should include special atten- tion to those equipment items previously identified as especially important to chloropicrin manufacture end storage. Preventing equipment failures that could lead to overheating (temperatures above 233.6°F) is crucial to prevent- ing potentially explosive decomposition since this is a special characteristic of chloropicrin. Ensuring the use of proper construction materials in all repairs or replacements of equipment is important. Maintenance practices should also ensure that contact of chloropicrin with strong oxidizers is prevented. Other aspects of a sound maintenance program include special care for corrosion monitoring, relief valve testing, and general maintenance of those areas of the facility with the largest inventories of chloropicrin. All modifications should be forcally approved to ensure that modifications do not create a new potential release hazard in the modified system. 33 ------- 4.7 CONTROL EFFECTIVENESS It is difficult to quantify the control effectiveness of preventive and protective measures in reducing the probability and magnitude of accidental releases. Preventive measures, vhich may involve numerous combinations of process design, equipment design, and operational measures, are especially difficult to quantify because they reduce a probability rather than a physical quantity of a chemical release. Protective neasures are more analogous to traditional pollution control technologies. Thus, it may be easier to quan- tify their efficiency in reducing a quantity of chemical that could be re- leased. Preventive measures reduce the probability of an accidental release by increasing the reliability of process systems operations and equipment. Control effectiveness can thus be expressed for both qualitative end quanti- tative improvements by probabilities. Table 4-2 summarizes some of the major design, equipment, and operational measures for the hazards identified for chloropicrin applications in the SCAQMD. The items listed in Table 4-2 are for illustration only and do not necessarily represent a satisfactory control option in all cases. When viewed from a broad perspective, these control options Geem to reduce the risk associated with on accidental release, how- ever, there are undoubtedly specific cases where these control options will not be appropriate. Each case must be evaluated individually. 4.8 ILLUSTRATIVE COST ESTIMATES FOR CONTROLS This section presents cost estimates for different levels of controls and for specific release prevention and protection measure that might be found in the SCAQMD for chloropicrin process facilities. 34 ------- TABLE 4-2. EXAMPLES OF MAJOR PREVENTION AND PROTECTION MEASURES FOR CKLOROPICRIN RELEASES Hazard Area Prevention/Protection Reactor feed streams Line, pipe, and valve failure Human error Container failure Vehicular collusions Corrosion Overheated reactor Overpressure Overfilling Atmosphere releases from relief discharges Storage tank or line rupture Redundant flow control loops; minimal overdesign of feed systems More frequent inspections and maintenance Increased training and supervision; use of checklists; use of automatic systems Adequate pressure relief; inspection and maintenance; corrosion monitoring; siting away from fire and mechanical damage Location; physical barriers warning signs; training Inspections, maintenance, and corrosion monitoring Redundant temperature sensing and alarms; interlocked nitromethane feed shut off Enhanced pressure relief; not isolatable; adequate size; discharge not restricted Redundant level sensing, alarms and interlocks, training of operators Emergency vent scrubber system Enclosure vented to eoergency scrubber system; diking; foams; neutralization; inspection and non-destructive testing 35 ------- 4.6.1 Prevention and Protection Measures Preventive measures reduce the probability of an accidental release fron a process or storage facility by increasing the reliability of both process systems operations and equipment. Along with an increase in the reliability of a system is an increase in the capital and annual costs associated with incorporating prevention and protection measures into a system. Table 4-3 presents costs of some of the major design, equipment, and operational mea- sures applicable to the primary hazards identified in Table 4-2 for chloro- picrin facilities in the SCAQMD. 4.8.2 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. At minimum, equipment and procedures should be in accordance with applicable codes, standards, and regulations; however, addi- tional measures can provide extra insurance against sn accidental release. The levels of control concept is a way 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 hazardous material. 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 cocts associated with this level are higher than the baseline system costs. The third level of control ia "Level 2." This system incorporates both the "Baseline" and "Level 1" systems with additional modifications designed 36 ------- TABLE 4-3, ESTIMATED TYPICAL COSTS OF SOME PREVENTION AND PROTECTION MEASURES FOR CHLOROPICRIN RELEASES3 Prevention/Protection Measure Capital Cost (1986 $) Annual Cost (1986 S/yr) Pressure relief - relief valve 1000-2000 - rupture disk 1000-1200 Physical barriers - curbing 750-1000 - 3 ft retaining wall 1500-2000 Flow control loop 4000-6000 Temperature sensor 250-400 Interlock system for feed shut-off 1500-2000 Alarm system 250-500 Diking - 3 ft high 1200-1500 - top of tank height 7000-7500 Corrosion monitoring^ Increased inspections and maintenance 120-250 120-150 90-120 175-250 500-750 30-50 175-250 30-75 150-175 850-900 200-400 250-500 ^ased on a 10.000 gallon fixed chloropicrin storage system and a 2,000 gallon batch chlorination reactor system. Based on 10-20 hr 3 $20/hr. °Based on 12.5-25 hr 6 $20/hr. 37 ------- specifically for the prevention of an accidental release, such as alarm and interlock systems. The extra accidental release prevention measures incoroo- rated into "Level 2" are reflected in its cost, which is much higher than that of the baseline aysten. 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 assure safe operation. These estimates are for illustrative purposes only. It is doubtful that any specific installation would find all of the control options listed in these tables appropriate for their purposes. An actual systen is likely to incorporate some items from each level of control and also some control options not listed here. The purpose of these estimates is to illustrate the relationship between cost and control, not to provide an equipment check list. Levels of control cost estimates were prepared for a 69-ton fixed chloropicrin storage tank with 10,000 gal capacity and a chloropicrin reactor system. These systems are representative of storage and process facilities that might be found in the SCAQMD. A.8.3 Cost Summaries Table 4-4 summarizes the total capital and annual costs for each of the three levels of control for a chloropicrin storage system and a chloropicrin reactor system. The costs presented correspond to the systems described in Table 4-5 and Table 4-6. Each of the level costs include the cost of the basic system plus any controls. Specific cost information and breakdown for 38 ------- TABLE 4-4. SUMMARY COST ESTIMATES OF POTENTIAL LEVELS OF CONTROLS FOR CHLOROPICRIN STORAGE TANK AND BATCH REACTOR System Level of Control Total Capital Cost (1986 $) Total Annual Cost (1986 $/yr) Chloropicrin Storage Tank; 69 ton Fixed Storage Tank. With 10.000 gallon Capacity Chloropicrin Reactor System With 2,000 gallon Batch Chlorination Reactor Baseline Level No. 1 Level No. 2 Baseline Level No. 1 Level No. 2 40,000 363.000 532,000 62.000 368.000 445.000 5,600 43,000 63.000 9,000 46,000 53,000 39 ------- TABLE 4-5: EXAMPLE OF LEVELS OF CONTROLS FOR CHLOROPICRIN STORAGE TANK Process: 69 ton fixed chloropicrin storage tank 10.000 gal Controls Baseline Level Ho. 1 Level No. 2 Process: None Flow: Single check- valve on tank- process feed line. Temperature: None Pressure: Quantity: Single pressure relief valve, vent to atmos- phere. Local level indicator. None Add second check valve. None Add second relief valve, secure non-isolatable. Vent to limited scrubber. Provide local pressure indicator. Add remote level indicator. None Add a reduced-pressure device with internal air gap and relief vent to containment tank or scrubber. Add temperature indicator. Add rupture disks under relief valves. Provide local pressure indication on space between disk and valves. Add level alarm. Add high-low level inter- lock shut-off for both inlet and outlet lines. Location: Materials of Construction: Away from traffic. Away from traffic and flammables. Carbon steel Carbon steel with added corrosion allowance. Away from traffic, flammables, and other hazardous processes. Kynar®-lired carbon steel. Vessel: Piping: Tank pressure rating: 15 psig Sch. 40 carbon steel. Tank pressure rating: 25 psig Sch. 80 carbon steel.¦ Tank pressure rating: 50 psi% Sch 80 Kynar®-lined carbon steel. (Continued) A reduced pressure device is a modified double check valve. 40 ------- TABLE 4-5 (Continued) Process: 69 ton fixed 10.000 gal chloropicrin storage tank Controls Baseline Level No. 1 Level No. 2 Process Machinery: Centrifugal pump. Centrifugal pump, carbon steel, Kynar®-lined stuffing box construction, seal. double capacity mechanical seal. Magnetically-coupled centrifugal pump, Kynar®-lined construction. Enclosures: None Steel building. Concrete building. Diking: None 3 ft high dike. Top of tank height, 10 ft. Scrubbers: None Alkaline scrubber. Same Mitigation: None Alkaline sprays. Foam system. ------- TABLE 4-6. EXAMPLE OF LEVELS OF CONTROLS FOR CHLOROPICRIN MANUFACTURE Process: Batch chlorination reactor system Controls Baseline Level No. 1 Level No. 2 Process: Temperature: Pressure: Flow: Quantity: Mixing: Composition: Corrosion: Materials of Construction: None Local temperature indicator. Single pressure relief valve. Vent to atmosphere. Local flow indicator on feed lines. None Provide adequate mixing. None Visual inspections. Carbon steel Add reactor cooling system. Add redundant sensing and alarm. Add remote indicator. Add loca1 pressure indicator on tank. Vent relief valve to scrubber. Add remote indicators. None Add alarm on loss of agitation. None Increased monitoring and inspections. Carbon steel with added corrosion allowance. Use of interlock systems. Add temperature switch to shut off nitromethane feed when temperature rises above a set point. Add rupture disk and provide local pressure indication on space between disk and valve. Add flow switch to shut off nitrouethane feed. Level alarm. Interlock nitromethane feed on loss of mixing. None Same Type Kynar°-lined carbon steel. 42 (Continued) ------- TABLE 4-6 (Continued) Process: Batch chlorination reactor system Controls Baseline Level No. 1 Level No. 2 Vessel: Piping: Process Machinery: Protective Barrier: Tank pressure rating: 25 psig Sch. 40 carbon steel. Centrifugal pump, carbon steel construction, stuffing box. None Tank pressure rating: 25 psig Sch. 80 carbon steel. Centrifugal pump Kynar®-lined construction, double mechanical seal. Curiiig around reactor. Tank pressure rating: 25 psig Sch. 80 Kynar®-lined carbon steel. Magnetically- couple centrifugal pump, Kynar*-lined construction. 3 ft. high retaining wall. Enclosures: Scrubbers: Mitigation: None None None Steel building. Alkaline scrubbers. Alkaline sprays. Concrete building. Same Foam system. 43 ------- each level of control for both the storage and process facilities are pre- sented in Tables 4-7 through 4-12. 4.8.4 Equipment Specifications and Detailed Costs Equipment specifications and details of the capital cost estimates for the chloropicrin storage and the chloropicrin reactor systems are presented in Tables 4-13 through 4-20. 4.8.5 Methodology Format for Presenting Cost Estimates— Tables are provided for control schemes associated with storage ard process facilities for chloropicrin showing capital, operating, and total annual costs. The tables are broken down into subsections comprising vessels, piping and valves, process machinery, instrumentation, and. procedures and practice. Presenting 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 4-21 defines the cost elements comprising total fixed capital as it is used here. The computation of total fixed capital, as shown in Table 4-21, begins with the total direct cost for the system under consideration. This tof>l direct cost is the total direct installed cost of all capital equipment comprising the system. Depending on the specific equipment item involved, the direct capital cost was available or was derived from uninstalled costs by computing costs of installation separately. To obtain the total fixed capital cost, other costs obtained by using factors are added to the total fixed direct costs. 44 ------- TABLE 4-7. ESTIMATED TYPICAL CAPITAL AND ANNUAL COSTS ASSOCIATED WITH BASELINE CHLOROPICRIN STORAGE SYSTEM Capital Cost Annual Cost (1986 $) (1986 $/Yr) VESSELS: Storage Tank 26,000 3,000 PIPING AND VALVES: Pipework 3,000 350 Check Valves 290 30 Ball Valves (5) 1,700 200 Relief Valve 1,000 120 PROCESS MACHINERY: Centrifugal Pump 5,400 620 INSTRUMENTATION: Pressure Gauges CO 1.5C0 170 Liquid Level Gauge 1,500 170 PROCEDURES AND PRACTICES: Visual Tank Inspection (external) 15 Visual Tank Inspection (internal) 60 Relief Valve Inspection 15 Piping Inspection 300 Piping Maintenance 120 Valve Inspection 30 Valve Maintenance 350 TOTAL COSTS 40,000 5,600 45 ------- TABLE 4-8. ESTIMATED TYPICAL CAPITAL AND ANNUAL COSTS ASSOCIATED WITH LEVEL 1 CHLOROPICRIN STORAGE SYSTEM Capital Cose Annual Cose (1986 $) (1986 $/yr) VESSELS: Storage Tank 53.000 6,200 PIPING AND VALVES: Pipework 4.000 520 Check Valves 560 70 Ball Valves (5) 1.700 200 Relief Valve 2,000 240 PROCESS MACHINERY: Centrifugal Pump 13.000 1.500 INSTRUMENTATION: 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 SCRUBBER: Alkaline Scrubber 269,000 31.000 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 363.000 43.000 46 ------- TABLE 4-9. ESTIMATED TYPICAL CAPITAL AND ANNUAL COSTS ASSOCIATED WITH LEVEL 2 CHLOROPICRIN STORAGE SYSTEM Capital Cost Annual Co6t (1986 $) (1986 $/yr) VESSELS: Storage Tank 173.000 20,000 PIPING AND VALVES: Pipework 10,000 1,100 Reduced Pressure Device 1,500 170 Ball Valves (5) 1,700 190 Relief Valves (2) 2,000 250 Rupture Disks (2) 1,100 1,130 PROCESS MACHINERY: Centrifugal Pump 19,000 2,200 INSTRUMENTATION: Temperature Indicator 2,200 260 Pressure Gauges (6) 2,200 260 Flow Indicator 3,700 430 Load Cell 16,000 1,800 Remote Level Indicator 1,900 220 Level Alarm 380 45 High-Low Level Shutoff 1,900 220 ENCLOSURES: Concrete Building 19,000 2,200 SCRUBBERS: Alkaline Scrubber 269,000 31,000 DIKING: 10 ft. High Concrete Dike 7,600 880 PROCEDURES AND PRACTICES: Visual Tank Inspection (external) 15 Visual Tank Inspection (internal) 60 Relief Valve Inspection 50 Piping Inspection 300 Piping Maintenance 120 Valve Inspection 35 Valve Maintenance 400 TOTAL 00STS 5J2.000 63,000 47 ------- TABLE 4-10. ESTIMATED TYPICAL CAPITAL AND ANNUAL COSTS ASSOCIATED WITH BASELINE CONTINUOUS CHLOROPICRIN PRODUCTION Capital Cost Annual Cost (1986 $) (1986 $/yr) VESSELS: Batch Reactor 34,000 4,000 PIPING AND VALVES: Pipework 6,900 830 Ball and Globe Valves (4) 2,200 260 Relief Valve 1,000 120 PROCESS MACHINERY: Centrifugal Pump 5,200 620 INSTRUMENTATION: Pressure Gauges (3) 1,100 130 Flew Control Loops (2) 11,000 1,300 PROCEDURES AND PRACTICES: Visual Tank Inspection (external) 15 Visual Tank Inspection (internal) 60 Relief Valve Inspection 15 Piping Inspection 600 Piping Maintenance 250 Valve Inspection 40 Valve Maintenance 400 TOTAL 00STS 62,000 9,000 48 ------- TABLE 4-11. ESTIMATED TYPICAL CAPITAL AND ANNUAL COSTS ASSOCIATED WITH LEVEL 1 CONTINUOUS CHLOROPICRIN PRODUCTION Capital Cost Annual Cost (1986 $) (1986 $/yr) VESSELS: Batch Reactor 52.000 6,300 PIPING AND VALVES: Pipework 13,000 1,600 Ball and Globe Valves (A) 2,200 260 Relief Valve 1,000 120 PROCESS MACHINERY: Centrifugal Pump 12,000 1,500 INSTRUMENTATION: Pressure Gauges (3) 1,100 130 Flow Indicator 3,600 430 Flow Control Loops (2) 11,000 1,300 Temperature Indicator 2,200 260 Temperature Alarm 360 45 Temperature Sensor 360 45 DIKING: Curbing Around Reactor 910 110 ENCLOSURE: Steel Building 8,300 1,000 SCRUBBER: Alkaline Scrubber 260,000 31,000 PROCEDURES AND PRACTICES: Visual Tank Inspection (external) 15 Visual Tank Inspection (internal) 60 Relief Valve Inspection 15 Piping Inspection 600 Piping Maintenance 250 Valve Inspection 40 Valve Maintenance 400 TOTAL COSTS 368,000 46,000 49 ------- TABLE 4-12. ESTIMATED TYPICAL CAPITAL AND ANNUAL COSTS ASSOCIATED WITH LEVEL 2 CONTINUOUS CHLOROPICRIN MANUFACTURE Capital Cost Annual Cost (1986 $) (1986 $/yr) VESSELS: Storage Tank 105,000 13,000 PIPING AND VALVES: Pipework 29,000 3.500 Ball and Globe Valves (A} 1.700 260 Relief Valve 2,000 120 PROCESS MACHINERY: Centrifugal Pump 19.000 2.200 INSTRUMENTATION: Pressure Gauges (A) 1,500 170 Flow Indicator 3.600 430 Flow Interlock System 1.800 220 Liquid Level Gauge 1,500 170 Remote Level Indicator 1,800 220 Level Alarm 360 45 Temperature Sensor 360 45 Temperature Switch S40 65 Temperature Alara 360 45 Temperature Indicator 1,800 220 Mixing Interlock System 1,800 220 ENCLOSURES: Concrete Building 11,000 1,300 SCRUBBER: Alkaline Scrubber 260,000 31,000 DIKING: 3 ft. Retaining Wall 1,600 200 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 445,000 33,000 50 ------- TABLE 4-13. EQUIPMENT SPECIFICATIONS ASSOCIATED WITH CHLOROPICRIN STORAGE SYSTEM Equipment Item Equipment Specification Reference VESSELS: Storage Tank PIPING AND VALVES: Pipework Check Valve Ball Valve Relief Valve Reduced Pressure Device Rupture Disk PROCESS MACHINERY: Centrifugal Pump Baseline: 10,000 gallon carbon 18,19.20. steel storage tank, 15 psig rating IS Level #1: 10,000 gallon carbon steel with 1/8 inch corrosion protection, 25 psig Level 02s 10,000 gallon Kynar®-lined carbon steel, 50 p6ig Baseline: 100 ft. of 2 in. Schedule 22 40 carbon steel Level 01: 2 in. schedule 80 carbon steel Level 02: 2 in. schedule 80 Kynar®-lined carbon steel 2 in. vertical lift check 19,23 valve, carbon steel construction 2 in. Class 300, carbon steel 18,19,23 body 1 in. z 2 in.. Class 300 inlet and 19 outlet flange, angle body, closed bonnet with screwed cap, carbon steel body Double check valve type device with 18 internal air gap and relief valve 1 in. Monel® disk and carbon 18,20,24 steel holder Baseline: Single stage, carbon steel 19,25 construction, stuffing box, 100 gpm capacity. Level 01: Single stage, Kynar®-lined carbon steel construction, double mechanical seal Level 02: Kynar®-lined carbon steel, 19,25 mechanically-coupled 51 (Continued) ------- TABLE 4-13 (Continued) Equipment Item Equipment Specification Reference INSTRUMENTATION: Temperature Indicator Pressure Gauge Flov Indicator Level Indicator Load Cell Level Alarm High-Low Level Shutoff ENCLOSURES: Building SCRUBBERS: DIKING: Thermocouple, thermowell, electronic 18,19,26 indicator Diaphragm sealed. Haetelloy C 18,19,26 diaphragm, 0-1,000 psi Differential pressure cell and transmitter, associated meter Differential pressure type indicator 18,26 Electronic load cell 18,26,27 Indicating and audible alarm 19.28,29 Solenoid valve, switch, and relay 18,19,26 system 28 Level #1: 26-gauge steel walls and 28 roof, door, ventilation system Level #2: 10 in. concrete walls, 26-gauge steel roof Level 01 & 2: Spray tower, Monel* 30 construction, alkaline sprays, A ft. x 12 ft. Level #1: 6 in. concrete walls 28 3 ft. high Level 02: 10 in. concrete walls, top of tank height 52 ------- TABLE 4-14. MATERIAL AND LABOR COSTS ASSOCIATED WITH BASELINE CHLOROPICRIN STORAGE SYSTEM Materials Cost Labor Cost Direct Costs Indirect Costs Capital Costs (1986 $) VESSELS: Storage Tank 12.000 5,400 17,400 6,100 26,000 PIPING AND VALVES: Pipework 600 1.400 2,000 700 3000 Check Valves 160 30 190 70 290 Ball Valves (5) 1.000 150 1,150 400 1.700 Relief Valve 650 50 700 250 1.000 PROCESS MACHINERY: Centrifugal Pump 1.500 1,100 3,600 1,300 5.400 INSTRUMENTATION: Pressure Gauges (4) 800 200 1,000 350 1.500 Liquid Level Gauge 800 200 1,000 350 1.500 TOTAL COSTS 18.000 9,000 27,000 9,500 40,000 53 ------- TABLE 4-15. MATERIAL AND LABOR COSTS ASSOCIATED WITH LEVEL 1 CHLOROPICRIN STORAGE SYSTEM Materials Labor Direct Indirect Capital Cost Cost Costs Costs Costs (1986 $) VESSELS: Storage Tank 25.000 11,000 36.000 13.000 53.000 PIPING AND VALVES: Pipework 1.000 2.000 3.000 1.000 4,000 Check Valves 320 60 380 130 560 Ball Valves (5) 1.000 150 1.150 400 1.700 Relief Valves (2) 1.300 100 1.400 500 2.000 PROCESS MACHINERY: Centrifugal Pump 6.000 2.600 8.600 3.000 13.000 INSTRUMENTATION: Pressure Gauges (4) 800 200 1.000 350 1.500 Flow Indicator 2.000 500 2.500 880 3.700 Liquid Level Gauge 800 200 1.000 350 1,500 Remote Level Indicator 1.000 250 1.250 440 1.900 ENCLOSURES Steel Building 4.600 2.300 6.900 2.400 10,000 SCRUBBER: Alkaline Scrubber 125.000 56.000 181.000 63.000 269.000 DIKING: 3 ft. High Concrete 390 510 900 32C 1.300 Diking TOTAL COSTS 170.000 76.000 245.000 86.000 363.000 54 ------- TABLE 4-16. MATERIAL AND LABOR COSTS ASSOCIATED WITH LEVEL 2 CHLOROPICRIN STORAGE SYSTEM Materials Labor Direct Indirect Capital Coat Cost Costs Costs Costs (1986 $) VESSELS: Storage Tank 80,000 PIPING AND VALVES: Pipework 4,000 Reduced Pressure Device 800 Ball Valves (5) 1,000 Relief Valves (2) 1,300 Rupture Disks (2) 650 PROCESS MACHINERY: Centrifugal Pump 9,000 INSTRUMENTATION: Temperature Indicator 1,200 Pressure Gauges (6) 1,200 Flow Indicator 2.0C0 Load Cell 8,400 Remote Level Indicator 1,000 Level Alarm 200 High-Low L*?vel Sbutoff 1,000 ENCLOSURES Concrete Building 6,100 SCRUBBERS: Alkaline Scrubber 125,000 DIKING: 10 ft. High Concrete 2,200 Dike 36,000 116,000 41,000 173,000 2,600 6,600 2,300 10,000 200 1,000 350 1,500 150 1,150 400 1,700 100 1,400 500 2,000 75 725 260 1,100 3,900 12,900 4,500 19,000 300 1,500 530 2,200 300 1,500 530 2,200 500 2,500 880 3.700 2,100 10,500 .3,700 16.000 250 1,250 440 1,900 50 250 90 380 250 1,250 440 1,900 6,600 12.700 4.400 19.000 >6.000 181,000 63.000 269,000 2,900 5,100 1,800 7,600 TOTAL COSTS 245,000 112.000 357.000 125.000 532.000 55 ------- TABLE 4-17. EQUIPMENT SPECIFICATIONS ASSOCIATED WITH CHLOROPICRIN MANUFACTURE Equipment Item Equipment Specification Reference VESSELS: Reactor PIPING AND VALVES: Pipework Ball valves Globe valves Relief valve Rupture disk PROCESS MACHINERY: Centrifugal pump INSTRUMENTATION: Level alarm Interlock system Pressure gauge Flow control loop Temperature indicator Temperature sensor 2,000 gallon batch reactor 18.19 Baseline: Schedule AO CPVC for bleach 22 solution. Schedule 40 carbon steel for chloropicrin Level tit Schedule 80 carbon steel Level 02: Schedule 80 Kynar®-lined carbon steel 2 in. Class 300. carbon steel body 2 in. Class 300, cast steel 1 in. x 2 in.. Class 300 inlet end outlet flange, angle body, closed bonnet with screwed cap, carbon steel body 1 in. Monel® disk and carbon steel flteel holder 18.19,23 18,19,23 19 18,20,24 Baseline: Single stage, carbon steel construction, stuffing box, 100 gpm capacity Level #1: Single stage, Kynar®-lined 19,25 construction, double mechanical seal Level 02: Kynar®-lined, magnetically- 19,25 coupled Indicating and audible alarm 19,28,29 Solenoid valve, switch, and relay 18,19,26 system 28 Diaphragm sealed, Hastelloy C 18,19,26 diaphragm, 0-1,000 psi 2 in. Globe control valve, 18,26 flowmeter and PID controller Thermocouple, thennowell. and 18,19,26 electronic indicator Thermocouple and associated thennowell 18,19.26 (Continued) 56 ------- TABLE 4-17 (Continued) Equipment Iteo Equipment Specification Reference DIKING: Level #1: 6 in. high concrete curing Level 82: 3 ft. high concrete retaining wall 28 ENCLOSURE: Level 01: 26 gauge steel wall6 and roof, door, ventilation system Level 62: 10 in. concrete walls, 26 gauge 6teel roof, door 28 SCRUBBER: Level 016 2: Spray tower, Monel® construction, alkaline sprays, A ft. x 12 ft. 30 57 ------- TABLE 4-18. MATERIAL AND LABOR COSTS ASSOCIATED WITH BASELINE CONTINUOUS CHLOROPICRIN PRODUCTION Materials Labor Direct Indirect Capital Cost Cost Cost s Costs Costs (1986 $) VESSELS: Batch Reactor 16.000 7,400 23.400 5.900 34.000 PIPING ATO VALVES: Pipework 1.800 3.000 4.800 1.200 6.900 Ball and Globe Valves (4) 1,000 500 1.500 380 2.200 Relief Valve 650 50 700 180 1.000 PROCESS MACHINERY: Centrifugal Pump 2,500 1,100 3,600 900 5,200 INSTRUMENTATION: Pressure Gauges (3) 600 150 750 190 1.100 Flow Control Loops (2) 6.000 1.500 7.500 1.900 11.000 TOTAL COSTS 29.000 14.000 43.000 11.000 62.000 58 ------- TABLE 4-19. MATERIAL AND LABOR COSTS ASSOCIATED WITH LEVEL 1 CONTINUOUS CHLOROPICRIN PRODUCTION Materiels Labor Direct Indirect Capital Cost Cost Costs Costs Costs (1986 $) VFSSELS: Batch Reactor 25.000 PIPING AND VALVES: Pipework 3,000 Ball and Globe Valves (4) 1.000 Relief Valve 650 PROCESS MACHINERY: Centrifugal Pump 6,000 INSTRUMENTATION: Pressure Gauges (3) 600 Flow Indicator 2,000 Flow Control Loops (2) 6,000 Temperature Indicator 1.200 Temperature Alarm 200 Temperature Sensor 200 DIKING: Curbing Around Reactor 500 ENCLOSURE: Steel Building 4,600 SCRUBBER: Alkaline Scrubber 125,000 TOTAL COSTS LI,000 36.000 9,000 52,000 6,000 9,000 2,300 13,000 500 1.500 380 2.200 50 700 180 1,000 2,600 8,600 2,200 12,000 150 750 190 1,100 500 2,500 630 3.600 1,500 7,500 1,900 11,000 300 1.500 380 2.200 50 250 60 360 50 250 60 360 130 630 160 910 1,200 5,800 1,500 8.300 56.000 181.000 45,000 260.000 176,000 80.000 256,000 64,000 368,000 59 ------- TABLE 4-20. MATERIAL AMD LABOR COSTS ASSOCIATED WITH LEVEL 2 CONTINUOUS CHLOROPICRIN PRODUCTION Materials Labor Direct Indirect Capital Cost Cost Costs CostB Costs (1986 $) VESSELS: Storage Tank 50,000 23,000 73.000 18.000 105.000 PIPING AND VALVES: Pipework 12.000 8.000 20.000 5.000 29.000 Bail and Globe Valves (4) 1.000 150 1,150 290 1.700 Relief Valve 1.300 100 1.400 350 2.000 PROCESS MACHINERY: Centrifugal Pump 9.000 3.900 12.900 3.200 19.000 INSTRUMENTATION: Pressure Gauges (4) 800 200 1,000 250 1.500 Flow Indicator 2.000 500 2.500 880 3.600 Flow Interlock System 1.000 250 1,250 310 1,800 Liquid Level Gauge 800 200 1,000 250 1,500 Remote Level Indicator 1.000 250 1,250 310 1,800 Level Alarm 200 50 250 60 360 Temperature Sensor 200 50 250 60 360 Temperature Switch 300 75 375 95 540 Temperature Alarm 200 50 250 60 360 Temperature Indicator 1.000 250 1,250 310 1.800 Mixing Interlock System 1.000 250 1,250 310 1.800 ENCLOSURES: Concrete Building 6,100 1.500 7,600 1.900 11.000 SCRUBBER: Alkaline Scrubber 125,000 56,000 181,000 45.000 260.000 DIKING: 3 ft. Retaining Wall 900 230 1,130 290 1,600 TOTAL COSTS 214.000 95.000 309,000 77.000 445.000 60 ------- TABLE A-21. FORMAT FOR TOTAL FIXED CAPITAL COST Item No. Iteir Cost 1 Total Material Cost - 2 Total Labor Cost - 3 Total Direct Cost Items 1+2 4 Indirect Cost Iteos (Engineering & Construction Expenses) 0.35 x Item 3B 5 Total Bare Module Cost Itens (3 + A) 6 Contingency « (0.05 x Irew 5)b 7 Contractor's Fee 0.05 x Iter: 5 8 Total Fixed Capital Cost Iteos (5+6+7) °For storage facilities, toe indirect cost factor is 0.35. For process facilities, the indirect cost factor is 0.25. ^For itorage facilities, the contingency cost factor is 0.05. For process facilities, the contingency cost factor is 0.10. 61 ------- The first group of other cost elements is direct costs. These include engineering and supervisicn, construction expenses, and various other ex- penses, such as administration expenses. These costs are computed by multi- plying total direct costs by a factor shown in Table 4-21. The factor is approximate, is obtained from the cost literature, and is based on previous experience with capital projects of a similar nature. Factors can have a range of values and vary according to technology area and individual tech- nologies vithin an area. Appropriate factors based on judgement and exper- ience were selected for this report. When the indirect costs are added to the total direct cost6, total bare module cost is obtained. Some additional cost elements, such as contractor's fee and contingency, are calculated by applying and adding appropriate factors to the total bare module cost, as shown in Table 4-21, to obtain the total fixed capital cost. Annual Cost—Annual costs are obtained for each equipment item by apply- ing a factor for both capital recovery and for maintenance expenses to the direct cost of each equipment item. Table 4-22 defines the cost elements and the appropriate factors comprising these costs. Additional annual costs are incurred for procedural items such as valve and vessel inspections, for example. The sum of these individual costs equals the total annual cost. Source of Information— Costs presented in this report are derived from cost information in existing published sources and also from recent vendor information. The objective of this effort was to present cost levels for ch?.oropicrin process and storage facilities using the best costs for available sources. The primary sources of cost information are Peters and Timmerhaus (18), Chemical Engineering (31), and Valle-Riestra (32), supplemented by other sources and references where necessary. Adjustments were made to update all costs to a June 1986 dollar basis. For some equipment items, well-documented costs were not available and they had to be developed from component costs. 62 ------- TABLE 1-22. FORMAT FOR TOTAL ANNUAL COST Item No. Item Cost 1 Total Direct Cost - 2 Capital Recovery on Equipment Items 0.163 x Iteo 1 3 Maintenance Expense on Equipment Items 0.01 x Item 1 4 Total Procedural Items - 5 Total Annual Cost Items (2+3 + 4) 63 ------- Costs in this document reflect the "typical" or "average" representation for specific equipment items. This restricts the use 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 might be incurred for a specific application. The costs in this report are considered to be "order of magnitude" with a ^+50 percent margin because costs 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 manual to those from other references, the user should be sure the design bases are comparable and that the capital and annual costs aB defined here are the same. Cost Updating— All costs in this report are expressed in June 1986 dollars. Cost3 reported in the literature were updated using cost indices for materials and labor. Costs expressed in base-year dollars may be adjusted to dollars for another year by applying cost indices as shown in the following equation: new base-year cost = old base-year cost x nf*f base year index old base year index 64 ------- The chemical Engineering (CE) Plant Cost Index was used in updating cost for this report. For June 1986. the index is 316.3. Equipment Costs— Host 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, scrub- bers. diking, and enclosures. The techniques used 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 ac the ba sis (January 1979 dollars) were determined using the following equation from Peters and Timmerhaus (18): Cost = [50(Weight of Vessel in Pounds)[Weight of Vessel in Pounds] The vessel weight is determined using appropriate deGign equations as given by Peters and Timmerhaus (18) that allow for wall 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 construction materials, as given in Peters and Timmerhaus (18). Vessel costs are updated using cost factors. Finally, a shipping cost amounting to 10 percent of the purchased cost is added to obtain the delivered equipment cost. ?ipinp.—Piping costs were obtained using cost information and data presented by Yamartino (22). A simplified approach is used in which it is assumed 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 Yamartino (22) permit cost determinations for various 65 ------- lengths. sizes, and types of piping systems. Using these fectors, a represen- tative estimate can be obtained for each of the storage and process facili- ties. Dikinp,—Diking costs were estimated using Mean's Manual (28) 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 volumetricelly included in the volume enclosed by the diking. These assumptions facilitate cost determination for any size diking system. Enclosures—Enclosure costs were estimated using Mean's Manual (28) 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 i6 ten-inches thick with a 26-gauge steel roof and a meral door. The steel building has 26 gauge roofing and siding and metal door. The cost of a ventilation system was determined using a typical 1,000 scfm unit and doubling the cost to account for duct work and requirements for the safe enclosure of hazardous chemicals. Scrubbers—Scrubber costs were estimated by the following equation from the Card (30) manual for spray towers based on the actual cubic feet per minute of flow at a chamber velocity of 600 feet/minute. Costs = 0 . 235 x (ACFM + 43,000) 3 A release rate of 1,000 ft /minute was assumed for the storage vessel systems and an appropriate rate was determined for process system based on the quan- tity of hazardous chemicals present in the system at any one time. For the chlorcpicrin reactor system, a release rate of 1,000 ft /minute was assumed. In addition to the spray tower, the costs also include pumps and a storage 66 ------- tank for the ccrubbing medium. The costs presented are updated to June 1986 dollars. Installation Factors— Installation costs were developed for all equipment items included in both the process and storage systems. The costs 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 (18) and Valle-Rie6tra (32). Table 4-23 liet6 the co6t factors used or the reference from which the cost was obtained directly. Many of the costs obtained frcn 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. 67 ------- TABLE 4-23. FORMAT FOR INSTALLATION COSTS Equipment Iten Factor or Reference Vessels: Storage Tank 0.45 Piping and Valves: Pipework Reduced Pressure Device Check Valves Gates Valves Ball Valves Relief Valves Rupture Disks Process Machinery: Centrifugal Pump Gear Pump Instrumentation: All Instrumentation Items 0.25 Enclosures: Ref. 28 Diking: Ref. 28 Scrubbers: 0.45 Ref. 22 Ref. 19 Ref. 19 Ref. 19 Ref. 19 Ref. 19 Ref. 19 0.43 0.43 68 ------- SECTION 5 REFERENCES 1. South Coast Air Quality Management District. File of Questionnaires from Toxic Chemical Industry Survey, 1985. 2. Macy, R. Constants and Physiological Action of Chemical Warfare Agents. Edgewood Arsenal, U.S. Army, 1941. 3. Kirk, R.E. and D.F. Othmer. Encyclopedia of Chemical Technology. Third Edition. John Wiley and Sons. Inc.. 1980. 4. Dean, J. (ed.). Lange's Handbook of Chemistry. Twelfth Edition, McGraw-Hill Book Comapny, New York. NY, 1979. 5. Material Safety Data Sheet: Great Lakes Chemical Corporation, West Lafayette, Indiana, March 1986. 6. Occupational Health Guideline for Chloropicrin. National Institute for Occupational Safety and Health/Occupational Safety and Health Association (NI0SH/0SHA) Publication, September 1978. 7* Tatken, R. L. and R. J. Lewis (eds.). Registry of Toxic Effects of Chemical Substances (RTECS). 1981-82 Edition. 3 Volumes. NIOSH Con- tract No. 210-81-8101. DrtHS (NIOSH) Publ. No. 83-107. June 1983. 8. Sax, H. I. Dangerous Properties of Industrial Materials (4th Edition). Van Nostrand Reinhold Company. New York, NY, 1975. 9. Warthing, C.R. (ed.). The Pesticide Manual; A World Compendium, Seventh Edition, Croydon, England, The British Crop Protection Council, 1983. 10. NI0SH/0SHA Pocket Guide to Chemical Hazards. DHEW (NIOSH) Publication No. 78-210, September 1985. 11. Wilhelm, J. M. U.S. Patent 3,106,588. October 8, 1963. 12. Telephone conversation between D.S. Davis of Radian Corporation and a representative of Great Lakes Chemical Company, West Lafayette, IN, April 1986. 13. Hart, F.C. Technology for the Storage of Hazardous Liquids, A State-of—the-Art Review, The Bureau of Water Resources, Albany, NY, Revised Edition, March 1985. 14. DeRenzo, D. J. (ed.). Corrosion Resistant Materials Handbook (4th Edition). Noyes Data Corp., Park Ridge, NJ, 1985. 15. Green, D. W. (ed.). Perry's Chemical Engineers* Handbook (6th Edition). McGraw-Hill Book Company, New York. NY. 1984. 69 ------- 16. Lees, F. P. Loss Prevention in the Process Industries - Hazard Identifi- cation, Assessment and Control, Butterworth & Company Ltd.. London. England. Volumes 1 & 2. 1980. 17. Bennett. G. F., F. S. Feates. and I. Wilder. Hazardous Material Spills Handbook. McGraw-Hill Book Company. New York, NY. 1982. 1®* Peters, M. S. and K. D. Timmerhaus. Plant Design and Economics for Qiemical Engineers. McGraw-Hill Book Company, New York, NY, 1980. 19. Richardson Engineering Services, Inc. The Richardson Rapid Construction Cost Estimating System, Volume 1-4. San Marcos, CA. 1986. 20. Pikulic, A. and H. E. Diaz. Cost Estimating for Major Process Equipment. Chemical Engineering. October 10, 1977. 21. Hall, R. S. Matley, and K. J. McNaughton. Cost of Process Equipment. Chemical Engineering. April 5, 1982. 22. Yarmartino. J. Installed Cost of Corrosion—Resistant Piping — 1978. Chemical Engineering, November 20, 1978. 23. Telephone conversation between J.D. Quass of Radian Corporation and a representative of Mark Controls Corporation. Houston, TX, August 1986. 24. Telephone conversation between J.D. Quass of Radian Corporation and a representative of Fike Corporation, Houston. TX, August 1986. 25. Green. D. W. (ed.). Perry's Chemical Engineers' Handbook (Sixth Edi- tion), Chemical Engineering, September 21, 1970. 26. Liptak, B. G. Cost of Process Instruments. Chemical Engineering, September 7, 1970. 27. Liptak, B. G. Cost of Viscosity, Weight, Analytical Instruments. Chemical Engineering, September 21, 1970. 28. R. S. Means Company, Inc. Building Construction Cost Data, 1986 (44th Edition). Kingston, MA. 29. Liptak, B. G. Control-Panel Costs. Process Instruments. Chemical Engineering. October 5, 1970. 30. Capital and Operating Costs of Selected Air Pollution Control Systems. EPA-450/5-80-002, U.S. Environmental Protection Agency. 1980. 31. Cost indices obtained from Chemical Engineering. McGraw-Hill Publishing Company. New York. NY, June 1974, December 1985, and August 1986. 32. Valle-Riestra, J. F. Project Evaluation in the Chemical Process Indus- tries. McGraw-Hill Book Company, New York, NY, 1983. 70 ------- APPENDIX A GLOSSARY This glossary defines selected terms used in the text of this manual which might be unfamiliar to seme 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 environmental permits and/or results in toxic concentrations in the air that are a potential health threat to the surround- ing community. Assessment: The process whereby the hazards which have been identified are evaluated in order to provide an estimate for the level of risk. Cavitation; The formation and collapse of vapor bubbles in a flowing liquid. Specifically, the formation and collapse of vapor cavities in a pump when there is sufficient resistance to flow at the inlet side. Containment/control; A system to which toxic emissions from safety relief 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 continuous 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 pro- tracted failure. 71 ------- 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 pro- duce. refine or repackage chemicals, or a location where a large enough inven- tory of chemicals are scored 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 situation, its causes and consequences relating to a defined potential, e.g.. Hazard Identification. Mild steel: Carbon steel containing a maximum of about 0.25% carbon. Mild steel is satisfactory for use where severe corrodants are not encountered or where protective coatings can be used to prevent or reduce corrosion rates to a-jceptable levels. Mitigation: Any measure taken to reduce the severity of the adverse effects associated with the accidental release of a hazardous chemical. Passivation film: A layer of oxide or other chemical compound of a metal on its surface that acts as a protective barrier against corrosion or further chemical reaction. Plant: A location at which a process or set of processes are used to produce, refine or repackage chemicals. 72 ------- Prevention: Design and operating measures applied to a process to ensure that primary containment cf 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 ma- chinery used in a facility for handling chemicals under normal operating con- ditions. Probability/potential: A measure, either qualitative or quantitative, that an event will occur within some unit of rime. Process: The sequence of physical and chemical operations 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 cheaical that has breached primary containment, but before an uncontrolled release to the envi- ronment has occurred. Qualitative Evaluation: Assessing the risk of an accidental release at a fa- cility in relative terms: the end result of the assessment being a verbal de- scription of the risk. Quantitative Evaluation: Assessing the risk of an accidental release at a facility in numerical terms; the end result of the assessment being some type of number reflects risk, such as faults per year or mean time between failure. Reactivity: The ability of one chemical to undergo u chemical reaction with another chemical. Reactivity of one chemical is always measured in reference to the potential for reaction with itself or with another chemical. A 73 ------- chemical is sometimes said *o be "reactive," or have high "reactivity,n with- out reference to another chemical. Vsially this means that the chemical has the ability to react with common materials such as water, or common materials of construction svch as carbon steel. 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 equipment fails. Redundant equipment can be installed to backup all or selected portions of a control system. Risk? The probability that a hazard may be realized at any specified level in a given span of time. Secondary Containment; Process equipment specifically designed to contain material that has breached primary containment before the material is released to the environment and becomes an accidental release. A vent duct and scrub- ber that are attached to the outlet of a pressure relief o'evice are examples of secondary containment. Toxicity: A measure of the adverse health effects of exposure to a chemical. 74 ------- APPENDIX B TABLE B-l. METRIC (SI) CONVERSION FACTORS Quantity To Convert From To Multiply By Length: Area: Volume: Mass (weight): Pressure: Temperature: Caloric Value; Enthalpy: Specific-Heat Capacity: Density: Concentration: Flovrate: Velocity: Viscosity: in M in ft3 f? gal lb short tor. (ton) short ton (ton) atm nun Hg psia psig °F °C Btu/lb Btu/lbnol kcal/gmol Btu/lb-°F lb/ft3 lb/gal oz/gal quarts/gal gal/min ga^/day ft /min ft/min ft/sec centipoise (CP) cm cm„ cm. 3 o kg Mg metric ton (t) kPa kPa kPa kPa* °C* K* kJ/kg kJ/kgmol kJ/kgmol kJ/kg-°C kg/nu kg/m, k§'°3 eg /m m^/min n^/day m /min m/min m/sec kg/m-s 2.54 0.3048 6.4516 0.0929 16.39 0.0283 0.0038 0.4536 0.9072 0.9072 101.3 0.133 6.895 (psig +14.696)x(6.895) (5/9)x(°F-32) °C+273.15 2.326 2.326 4.184 4.1868 16.02 119.8 25,000 0.0038 0.0038 0.0283 0.3048 0.3048 0.001 *Calculate as indicated 75 ------- HWJEMWW.JJE JJ-»W3 * tlium, *WLM|U nyw ¦MMaiW ¦ W^W'H1. w«- 'W g1*.^ #Wj& *l,Hg '»'¦¦ T w o ------- |