Document zQYJza1nwXqJ6n0m4XryMEKg7

_ COur _. Aid for OSHA compliance: f 14thCT 5 Prc-ecr: v- s *Qn Judicial Dia - - - no. 91-1U-: Safety Chart for Common Solvents ONE OF THE POTENTIALLY MOST HAZ ARDOUS classes of chemicals in common use is Act standards (Section 1910.93) require that anyone using these chemicals must be protected from expo the industrial solvent group. Definitions of these hazsure above certain levels or beyond certain periods of ards arc found in many reference books, but such time, and, therefore, knowledge of the subject is source material is not easily available to most plant mandatory. engineers not directly involved in the chemical indus The accompanying safety chart lists the characteris tries. However, the Occupational Safety and Health tics of the most common industrial solvents and their - Acetone n-Amyl Acetate n-Amyi Alcohol Benzene (Benzol) n-Butyl Acetate ! '' ; -M . -r 134 293 280 .. ...... OIC.C.) 77IC.C.) 100(C.C.) 176 12IC.C.) 259 92IT.O.C.) sec - Butyl Acetate Butyl Alcohol 234 66IC.C.) 244 1141T.O.C.) Carbon Tetrachloride Chloroform Cyclohexanone Diacetone Alcohol 170 142 312 334 none none 147IC.C.) 15KO.C.) Diethyl Carbonate Diethylene Glycol Monoethyl Ether Diisobutyl Ketone Dipentene Ethyl Acetate 258 S9IO.C.) 395 205 (O.C.) 331 120IC.C.) 346 108 171 40(T.O.C.) Ethyl Alcohol (Ethanol) 173 61IC.O.C.) Ethylene Dichloride 182 70IO.C.) Ethylene Gh'col 340 141 (C.C.) Monobutyl Ether Ethylene Glycoi 275 10GIC.C.) Monoetnyl Ether Ethylene Glycol Monoethyl Ether Acetate 313 120(C.O.C.) Ethylene Givcol Monomethvl Ether 256 125(O.C.) tithvt-jnH Givcol Viunometnvt Ether Acetate 239 122IC.C.) Erhyl Lactate 309 115IC.C.) -M !} . 4k.i 2.6 12.8 1000 1.1 - 750 1.2 - 700 1.4 8.0 1000 1.7 15.0 740 1.7 1.7 18.0 650 ---- " ---- 1.1 - 847 -- 1190 -_ -- "-- -2.7 11.5 900 3.3 19.0 6.2 15.9 -" 2.6 15.7 1.7 -- 750 E40 472 460 715 - - 551 -- 1.55 "' 752 TIP ;r ... 1 1 -L- j . 'W ' 2.00 1000 2400 Skin irritant; headaches 4.50 100 525 Narcotic effect; irritant 3.04 -- -- Eye and respiratory imtsnt 2.77 25 80 Toxic by inhalation (skin) (skin) and skin absorption 0.88 150 710 Irritating to eves and respiratory tract; narcotic 4.00 200 950 Irritating to eyes and respiratory tract 2.55 100 300 Irritating to eyes, nose and throat; causes headache and dizziness " 10 65 Narcotic; can cause (skin) (skin) organ damage 4.12 25 120 Anesthetic; causes eye irritation 3.38 50 200 Eye and throat irritation mild narcotic 4.00 50 240 Irritating to eyes and mucous membranes; mild narcotic 4.07 - - Irritant 4.62 - Irritant 4.90 25 150 Narcotic and anesthetic effects 4.66 - - Irritant 3.04 400 1400 Irritating to eyes and respiratory passages; mud narcotic 1.59 1000 1900 Irritant; narcotic 3.35 50 200 Strong nritant 4.07 50 240 Irritant 3.10 200 740 Irritant; somewhat toxir (skin) (skin) 4.72 25 120 Irritant (skin) (skin) 2.62 2 3 80 Lan cause h'oad {akin) (skml tpnormslity 4.07 25 121 Irritant 1 | 1 4,07 Irritant SL 0A9058 FILE *7040 1 CONFIDENTIAL: Subject to Protective Order of 14th Judicial District Court No. 91-1145 hazards. To use this chart most effectively, one should understand the following definitions: Common chemical name of each solvent: Each solvent is listed by the most common chemical name or names. If your plant uses a solvent which is not listed here, it is possible that it is a trade named product for one which is listed. Check the label to determine if any one of these chemical names appears. If none is given, ask the manufacturer to provide the chemical name for the solvent. Boiling point in degrees Fahrenheit: Theoretically, this is the lowest temperature at which the vapor pressure exceeds the ambient pressure. Of course, this is also the temperature at which the solvents become Furfuryl Alcohol Heptane ife. T7! ...... k,-\ ,4 340 167IO.C.) 209 2SIC.C.) 1.8 1.2 iTi' v 16.3 6.7 Hexahydrophenol (Cyclohexanol) Hexane Isobutyl Alcohol Isopropyl Alcohol Kerosene 322 1541C.C.) 156 226 180 347-617 <-10 100(C.O.C.) 70<C.O.C.) 100-165(C,C.) -- 1.2 1.7 2.5 1.16 -- G.9 5.2 6.0 Methyl Acetate 136 14 4.1 13.0 Methyl Alcohol 'Methanol) 149 65(0,0.C.) 6.0 36.5 ihyl n-Amyl Ketone 303 120(0.0.) -- -- Methylene Chloride 104 none 15.5 in O2 66.4 mOj Methyl Ethyl Ketone (Butanone) Methyl Isobutyl Ketone (Hexone) 175 244 22IT.O.C.) 73 Mineral Spirits Nitroetnane Nitrpmethane 1 -Nitropropane Perchloroethylene 302-374 237 214 270 250 104(0.C.) 106IT.O.C.) 951C.C.) 120(T,O.C.) none 1.8 1.3 122F 1.1 7.3 - 11.5 8.0 212F 6.0 - Pine Oil 392-428 1721C.C.) " - n-Propyl Alcohol Propylene Oxide Stoddard Solvent T etrahyurofuran (THF) 207 93 428-572 150 59IC.C.) --35IT.O.C.) 100-110 KT.C.C.) 2.5 2.1 1.1 2.3 13.5 21.5 6.0 11.8 Toluol (Toiuen) 231 40(T.C.C.) 1.27 7.0 Trichlotoothane -1-1-1 1 ;ictt!crocthyi?ne T nme 165 159 309-333 none 9-jiC.C.) -- O.S - Vt.l&P Naphtna 212-2S4 20IC.C.) 0.9 6.0 Xv)o* (Xylene* 280 77 1.1 7.0 <: 11 - j' it 915 3.37 452 3.45 - 3.45 500 2.97 800 2.55 852 2.07 490 4.50 935 878 1224 960 2.55 1.11 -- 2.93 2.41 858 3.45 473 3.90 778 2.58 785 2.11 789 3.06 * 5.83 _- 812 2 07 - 2.00 450 -- 2.50 1026 -- 770 433 450 924 3.14 4.`3 4.S-1 - XG in "'VL. -Uj * iSSI ^ 5 20 Somewhat toxic 500 2000 Irritating to respiratory tract: mild narcotic 50 200 Irritant 500 1800 Irritant 100 300 Strong irritant 400 980 Irritant; mild narcotic - -- Irritant; headaches; moderate narcotic eftect 200 610 Narcotic and irritant 200 260 Strong narcotic and and mild irritant 100 465 Irritant and moderate narcotic 500 1740 Dangerous to eyes, narcotic 200 590 Irritant and narcotic 100 410 Irritating to eyes and mucous membrane; moderate narcotic 100 400 Irritant 100 310 Irutant 100 250 Irritant 25 90 Modeiately toxic 100 670 Toxic by inhalation or swallowing - - Cause or vsty slight allergy 200 500 Irritant 100 240 Moderate irritant 200 1150 Mild irritant 200 590 Irritating to eyes and mucous membrane; moderate narcotic 100 370 Moderete narcotic: can cauij orc^n damage 350 1900 Modei nte narcotic and irritant 100 535 jJdrcoT!<; `ind acidictive 100 560 Mild cju^c* of Jikrcy; toxic 100 400 OauhC'S ntoxrcai'on 100 435 Mocieiat-: in mut FILE #7040 SL 049059 Mflv it im-> . ,- BULLETIN 55A ichlori High-purity ethylene dichloride (EDC) is produced by PPG Industries' Chemicals Group at Lake Charles, Louisiana. PPG is one of the world's largest producers of ethylene dichloride and ships to customers in tank cars, tank trucks, barges and ocean-going ships. A terminal in Chicago, Illinois, also makes tank car and tank truck shipments. HEALTH HAZARDS Ethylene dichloride can be taken into the body by ingestion, inhalation or skin absorption. By any of these means it can be highly toxic. Acute poisoning may cause headache, dizziness, feelings of drunkenness, loss of consciousness, internal bleeding and death. Repeated exposures can bring on nausea, vomit- ing, stomach pain, irritated mucous membranes, loss of appetite, liver and kidney failure and possible death. Numerous cases of ethylene dichloride poisoning, both fatal and nonfatal, have been documented by the National Insti tute for Occupational Safety and Health. USES Almost three-quarters of the ethylene dichloride produced in the U.S. is used as an intermediate for making vinyl chloride. Other important intermediate uses for EDC include making 1,1,1-trichloroethane, trichlorethylene, perchlorethylene, ethylene amines and polysulfide elastomers. Ethylene dichloride is also used as a scavenging agent in tetraethyllead fuel additive compounds to prevent lead salts and lead oxide from depositing on engine cylinder walls. Ethlyene dichloride is an excellent solvent for greases, oils, fats and waxes. Due to the toxicity and flammability of EDC, other chlorinated solvents have displaced it in many applications. How ever, EDC has certain advantages and is still used for various solvent applications in chemical processing. GOVERNMENT SPECIFICATIONS PPG technical-grade ethylene dichloride meets the chemical and phys ical requirements of Military Specifica tion MIL-E-10662, Ethylene Chloride, Technical, including the requirement that 95% minimum distills between 82.5C and 84.5C at 760 mm Hg. TYPICAL PROPERTIES Chemical Names: Ethylene dichloride; ethylene chloride; 1,2-dichloroethane. Chemical Formula: CH2C1CH2C1 Molecular Weight: 98.97 Description: Ethylene dichloride is clear and colorless, but darkens Boiling Point, C F Freezing Point, C F slowly upon exposure to sunlight. It has an odor like chloroform. The liquid is mobile, volatile and flammable, and its vapor is toxic and flammable. 83 181 -35.9 -32.6 Flash Point, Tag open cup, C F O/o, or o> 18 65 Explosive Limits, volume % in air Autoignition Temperature, C F Viscosity at 25C, cps Density at 20C, pounds/gallon Refractive Index at 20C, nD Vapor Pressure at 20C, mm Hg Vapor Density, air = 1 4- A AA o<V%> ' s> / yjOyt.- v <y / ^ 6.2 to 15.9 413 775 0.78 ys o 10.5 V' A/, - o. 1.444 4 62.0 3.42 Solubility at 25C, g EDC/100 g water 0.84 at 20C, g water/100 g EDC 0.16 Solubility: Ethylene dichloride is soluble in most organic solvents. Reactivity: At moderate temperatures, ethylene dichloride is stable and resis tant to oxidation. When moisture-free at ordinary temperatures, it does not cor rode metals. But in contact with water at elevated temperatures, ethylene dichlo ride will corrode iron and certain other common metals. SL 049060 Specification and typical analysis: Purity, minimum % Color, maximum APHA Appearance Acidity, as HO, maximum ppm Alkalinity, as NaOH, maximum ppm Water, maximum ppm Free Chlorine Nonvolatile Residue, maximum ppm Total Chlorinated Hydrocarbons, low-boiling, maximum ppm Total Chlorinated Hydrocarbons, high-boiling, maximum ppm Total Oxygenated Compounds, maximum ppm C, and Higher Compounds, maximum ppm Total Soluble iron, maximum ppm Specific Gravity, 60760F Specification 99.7 10 clear, free of suspended matter 10 10 200 none 100 500 500 300 300 0.5 1.261-1.264 Typical Analysis 99.99 8 clear, free of suspended matter <1 -- 50 0 1 75 100 0 10 0.5 1.262 When ethylene dichloride is ingested, the predominant characteristic is blood disorder, including clotting problems. With skin absorption or inhalation, the first effects are headache, weakness, eye irritation and nausea. Ethylene dichloride has been found in human milk and in the exhaled breath of nurs ing mothers who were exposed to the chemical. Ethylene dichloride in contact with eyes or skin can result in local pain and irritation. Dermatitis may result from removal of natural skin oils and mois ture, although permanent eye or skin in jury has not been known to occur. If EDC is held close to the skin, as by con taminated clothing, severe irritation and moderate edema and necrosis may result. Chronic Exposure There are reports of two mild cases of human exposure for periods of two to five months which showed symptoms of central nervous system depression and gastrointestinal upset with nausea and vomiting. These persons recovered when removed from exposure. The liver and kidneys may be damaged by pro longed or repeated inhalation of the vapor. Recent animal studies conducted by the National Cancer Institute (NCI) have shown that ethylene dichloride can cause cancer in rats and mice by oral administration. However, in other studies of rats and mice exposed to EDC by inhalation, the results--although preliminary--did not confirm the NCI findings. The National Institute for Occupa tional Safety and Health (NIOSH) has recommended that the current OSHA permissible exposure limit be reduced from 50 ppm to 5 ppm (8-hour TWA) with a ceiling of 15 ppm. Although no evidence now exists showing that ethylene dichloride can cause cancer in human beings, PPG strongly suggests that EDC users review their health pro grams and operations and institute operating and housekeeping practices designed to limit employee exposure as much below currently established expo sure limits as practical. HANDLING AND STORAGE Ethylene dichloride is a flammable liquid. It introduces a fire hazard wher ever it is handled, stored or used. At high temperatures, such as occur in open flames, it decomposes to give off toxic and corrosive gases. Mixed with air at ordinary temperatures, ethylene dichloride is explosive within the limits? of 6.2 to 15.9% by volume. Fire and ex plosion hazards can be minimize! adequate ventilation, the proper t and arrangement of equipment, reasonable precautions and care in han dling. Information on the "Safe Handling and Use of Ethylene Dichloride" ap pears in Chemical Safety Data Sheet SD-18 published by the Manufacturing Chemists Association, 1825 Connect icut Avenue, N.W., Washington, D.C. 20009. The MCA also publishes Man ual Sheet TC-4 on "Unloading Flam mable Liquids from Tank Cars." PACKAGING AND SHIPPING PPG Industries delivers ethylene dichloride by tank car, barge, tank truck, drums and ship from the Lake Charles, Louisiana, plant. Tank car and tank truck shipments can also be made from a terminal in Chicago, Illinois. Tank car capacities include 8,000, 10,000 and 20,000 gallons. Tank truck capacity is generally 4,000 gallons. SAMPLES AND SERVICE Samples of ethylene dichloride are available in various sizes to meet c tomer requirements. The technical service staff of PPG dustries' Chemicals Group is available for consulting on handling, storage and use. A CP A c kP.cP op A -PV A SL 049061 P INDUSTRIES A-1009-55B 1M 179 PPG INDUSTRIES, Inc. Chemicals Group One Gateway Center Pittsburgh, PA 15222 Statements and methods presented are based upon the best available information and practices known to PPG Industries at present, but are not representations or warranties of performance, result Or comprehensiveness, nor do they imply any recommendations to infringe any patent or an offer of license under any patent The products ment,oned herein can be hazardous if not used properly. Any health hazard and safety information contained herem should be passed on to your customers or employees, as the case may be PPG Industries also tecommenos that, before use, anyone using or handling this product thoroughly read and understand the information and precautions on (tie label, as well as in other product safety publicat'ons such as the Material Safety Data Sheet Like all potentially hazardous matenals. this product must be kept out of tire reach of children Printed in U.S.A. comMOTiM^ oraer BULLETIN 115A vmyl Chloride Chemicals INDUSTRIES At its plants in Lake Charles, Louisi ana, and Guayanilla, Puerto Rico, PPG produces vinyl chloride monomer by the oxyhydrochlorination of ethylene. PPG holds more than 400 domestic and for eign patents on this process. Uninhibited VCM is quite stable and can be routinely shipped, handled and stored provided proper procedures, out lined below, are followed. To prevent polymerization in transit or storage, it is essential that the monomer be protected at all times from contact with air, oxy gen, moisture, catalytic impurities and light. PPG normally supplies VCM unin hibited. The use of uninhibited VCM eliminates the need for subsequent pro cessing to remove the inhibitor. More information ^appears in the PPG manual, "Vinyl Chloride Monomer Han dling and Properties," form A-994-115C. GRADES PPG Industries produces only poly mer-grade vinyl chloride monomer, USES Most vinyl chloride is polymerized to polyvinyl chloride (PVC) or copoly merized with other monomers such as PPG's vinylidene chloride. Vinyl chlo ride monomer should not be used as an aerosol propellant. TOXICITY The Occupational Safety and Health Standard on exposure to vinyl chloride published October 4, 1974, says: "Based on the demonstrated evidence of vinyl chloride monomer's carcinogenicity in three animal species (rats, mice and hamsters), and the substantial probabil ity that vinyl chloride monomer had been the causal agent in the cases of liver angiosarcoma found in workers both here and abroad, OSHA . . . pub lished a comprehensive proposal . . . to protect employees from hazards of exposure to vinyl chloride monomer." Stated in this OSHA standard is the following "Permissible exposure limit: At the PPG plant in Guayanilla, Puerto Rico, the company's modern 34,000-ton chemical tanker, S.S. Puerto Rican, receives a load of vinyl chloride monomer. At the Paulsboro. New Jersey terminal, the S.S. Puerto Rican's load of vinyl chloride monomer is transferred to the refrigerated storage tanks in the background. PROPERTIES Chemical Names: Chemical Formula: Molecular Weight: Vinyl chloride; vinyl chloride monomer; chloroethylene; -chloroethcne pr CH2CHCI; C=C 62.5 H''" '''Cl Description: At ordinary temperatures and pressures, vinyl chloride is a colorless gas with a mild, sweet odor. But as supplied in tank cars and trucks under pressure, it is a liquid. Vinyl chloride is highly volatile and its vapor is extremely flam mable. Boiling Point, C F Freezing Point, C F Flash Point, open cup, C -13.8 +7.0 -153.7 -245 -78 Autoignition Temperature, C F Liquid Density at 60 F Vapor Density, air =1 Vapor Pressure, psia at 0C 472 882 0.9192 2.15 25.1 F -108.4 20 C 49.2 40 C 87.6 Explosive Limits, volume % Solubility, water in monomer. in air at 25C (77F) 3.6 to 33 at 25C (77 F), weight % 0.11 Solubility: Vinyl chloride is relatively insoluble in water but soluble in most organic solvents. Reactivity: Vinyl chloride polymerizes exothermically in the presence of light, air, oxygen or catalysts. Heat alone will not initiate polymerization. Vinyl chlo ride is thermally stable to quite high temperatures. Although peroxide formation due to air exposure is a slow reaction, certain peroxide products are shocksensitive. Vinyl chloride is noncorrosive to metals when dry at normal tempera tures, but water and elevated temperatures accelerate corrosion. The double bond behaves as in other unsaturated compounds. The chlorine atom is relative ly inactive and is more stable than in saturated or allylic compounds. SL 049062 Specification and typical analysis: Appearance Color Acidity, as HC1, ppm Iron, as Fe, ppm (filtered sample) Nonvolatile residue, ppm Water, ppm Peroxide, as HaOi, ppm Acetaldehyde, ppm Acetylene, ppm Specification clear, free of suspended matter colorless. water-white 2 maximum 0.3 maximum 50 maximum 100 maximum 0.06 maximum 0.4 maximum 2 maximum* Typical Analysis- clear, free of suspended matter colorless. water-white < 0.1 0.1 5 50 0.01 <1 <1 Ihii maximum is sn industry standard; howwr, tils PPG product contains no detectable amount of acetylene. The major products of combustion include toxic and corrosive hydrogen chloride as well as carbon monoxide' and carbon dioxide. Under certain con ditions, traces of phosgene may be^^duced. Emission restrictions The EPA Standard for Vinyl Chlo ride was published in the Federal Regis ter on October 21, 1976 (see Code of Federal Regulations, 40CFR61, Nation al Emission Standards for Hazardous Air Pollutants). This regulation applies both to polymer and monomer plants. (1) No employee may be exposed to vinyl chloride at concentrations greater than 1 ppm (part per million by vol ume) averaged over any 8-hour period, and (2) No employee may be exposed to vinyl chloride at concentrations greater than 5 ppm averaged over any period not exceeding 15 minutes. (3) No employee may be exposed to vinyl chloride by direct contact with liquid vinyl chloride." In cases where these limits of expossure are exceeded, feasible engineering and work practice controls shall imme diately be used to reduce exposures to or below the permissible exposure limit. Wherever feasible engineering and work practice controls are not sufficient, they shall nonetheless be used to reduce ex posures to the lowest practicable level and shall be supplemented by the man datory use of respiratory protection. Respirators shall be selected from among those jointly approved by NIOSH and by MESA, under the pro visions of 30CFR Part 11, Besides the suspected carcinogenicity, vinyl chloride monomer vapor can pro duce immediate symptoms in persons exposed to high concentrations. The odor of vinyl chloride monomer is sweetish and the sense of smell can not be relied upon as a warning. High vapor concentrations may cause lung irritation, can cause dizziness and anes thesia, and may do other bodily damage in ways not yet ascertained. In all cases of overexposure, immediately remove the affected individual to fresh air and obtain medical attention. Liquid vinyl chlorjde monomer may cause frostbite because it evaporates so fast. If a polymerization inhibitor is included, it may cause local skin bums. However, most vinyl chloride monomer shipped today is not inhibited. Workers should wear eye protection and protective clothing to prevent skin contact with the liquid. If vinyl chlo ride gets on clothing or shoes, they should be removed immediately. If vinyl chloride contacts the skin, wash im mediately with soap and water. If vinyl chloride contacts the eyes, the eyes should be washed immediately and thoroughly with water for at least 15 minutes. Get medical attention. HANDLING AND STORAGE Detailed information appears in the PPG manual, "Vinyl Chloride Monomer Handling and Properties, form A-994115C. Fire hazard Vinyl chloride vapor is extremely flammable. Its explosive limits are be tween 3.6 and 33% by volume in air. Sufficient ventilation and the elimina tion of ignition sources are mandatory in areas where vapor concentrations may reach a flammable level. When a tank car is unloaded, both the car tank and the unloading pump must be elec trically grounded. Unloading tank cars If tank car valves are defective or leaking, do not unload. Telephone the PPG Chemicals plant at Lake Charles, Louisiana, 318-882-1200. Information on unloading tank cars and trucks ap pears in the PPG manual, "Vinyl Chlo ride Monomer Handling and Proper ties," form A-994-115C. Warning; Air should never be permit ted to enter vinyl chloride tank cars or other containers during or after unload ing. Close and seal all openings. Leave at least 10 psig of vinyl chloride vajjqr pressure in empty tank car being re turned . m PACKAGING AND SHIPPING o PPG Industries delivers vinyl ghf$- ride by ship, barge, tank car and rtaftk truck. There are three shippingj>qfni&: Lake Charles, Louisiana; Guajjaf^lfa, Puerto Rico; and Paulsboro, hfew^Iefsey w o PPG maintains a fleet of taftkocare for vinyl chloride service only. SjfclLqgfck are equipped for top unloading Tank car capacity is 180,000-pouM%jn weight. Tank trucks hold up to 40W0J) pounds. Ships and barges hold up* 15 several million pounds. ^ SAMPLES AND SERVICE 03 o The technical service staff of PPG In dustries' Chemical Division is available for consulting on handling, storage and use. No. 91-1145 PPG INDUSTRIES, Inc. Chemical Division One Gateway Center Pittsburgh, Pa. 15222 A-1000-115C 2M 877 Statements and methods presented arc based upon the best available information and practices known to PPC Industries at present, but arc not representations or warranties of performance, result or compre hensiveness, nor do they imply any recommendations to infringe any patent or an offer of license under any patent. The products mentioned herein can be hazardous if not used properly. Any health hazard and safety information contained herein should be passed on to your customers or employees, ar, the case may be PPG Industries also recommends that, before use, anyone using or handling this product thoroughly read and understand the information and pre cautions on the label, as well as in other product safety publications such as the Material Safety Data Sheet. Although this product is intended for industrial and manufacturing uses, it, as all potentially hazardous materials, must be kept out of the reach of children, Printed in U.S.A. SL 049063 4 BULLETIN 5QA Chlori INDUSTRIES CONFIDENTIAL: Subject to Protective Order of 14th Judicial District Court No. 91-1145 CONFIDENTIAL: Subject to Prot^cM^ r\ i of . ave Order >urt Ethyl chloride of high purity, typically 99.97%, is produced by PPG Industries Chemical Division at Lake Charles, Lou isiana. It is a technical-grade product for use by industry and is shipped by barge and tank car. The process by which PPG achieves this high-purity ethyl chloride is the hydrochlorination of ethylene. At temperatures above 12.4C (54F) ethyl chloride is a gas, but it is easily compressed to the liquid state for shipping and handling. USES About 80% of the ethyl chloride produced in the United States is currently consumed for making tetraethyl lead antiknock gas oline additives. Other uses that consume considerable tonnage include the manu facture of ethylcellulose and styrene. Tetraethyl lead is made by reacting ethyl chloride with lead-sodium alloy. Hous ton Chemical Company, a division of PPG Industries, produces this antiknock ingre dient. The high purity of PPG ethyl chlo ride makes processing easier and increases the yield of tetraethyl lead. Ethylcellulose is made by reacting ethyl chloride with soda cellulose. Ethylcellulose resin is used in paper coatings, printing inks, films, adhesives and molded plastics. It forms tough lacquers and thermoplastic materials. Styrene is made from ethylbenzene, which is mostly produced by the FriedelCrafts ethylation of benzene with ethyl chloride. Chemical intermediate. The ability of ethyl chloride to supply an ethyl group makes it useful for the synthesis of dye stuffs, fine chemicals and other materials. For example, ethyl chloride can be reacted with silicon to yield silanes with ethyl groups, which can then be converted to ethyl polysiloxane (silicone) compounds. TYPICAL PROPERTIES Chemical Names: Ethyl chloride; chloroethane. Chemical Formula: C2H5C1 Molecular Weight: 64.52 Description: Ethyl chloride is a colorless mobile liquid at 1 atmosphere below 12.4C (54F). Above the boiling point, it is a colorless gas. Ethyl chloride has an ethereal odor and is highly volatile and flammable. Freezing Point, "C -138.3 F -217 Flash Point, Tag open cup, C -43 F -45 Explosive Limits, volume % in air 3.16 to 15 Autoignition Temperature, C 519 F 966 Specific Heat at 0C, cal/ (g) (C) or Btu/ (lb)(F) 0.37 Heat of Vaporization at Boiling Point cal/g 92.5 Btu/lb 165.6 Viscosity at 10C, cps 0.279 Density at 20C, pounds/gallon 7.461 Refractive Index of Vapor, n^5 1.001 Vapor Pressure, mm Hg 0C (32F) 464 10C (50F) 692 20C (68F) Specific Gravity of Vapor (air=l) 1011 2.23 Solubility at 0C, g ethyl chloride/100 g water 0.447 g water/100 g ethyl chloride 0.07 Solubility: Ethyl chloride is soluble in most organic solvents. Reactivity: At ordinary temperatures the oxidation and hydrolysis of ethyl chloride take place slowly. In the absence of air and water, it can be used with most common metals up to 200C (392 F). Ethyl chloride bums with a green-edged flame, producing hydro gen chloride, carbon dioxide and water. It is thermally stable to 400C (752 F); thermal splitting yields ethylene and hydro gen chloride. The reactivity of ethyl chlo ride as an intermediate is often based on the affinity of alkali metal atoms for its chlorine atom. Specification and Typical Analysis: Purity, wt % Color, APHA Appearance Acidity as HC1, wt % Water, wt % Nonvolatile Residue, wt % Total Impurities, wt % Distillation Range, "C Specific Gravity, 0C/4C Specification Typical Analysis 99.5 minimum 99.97 20 maximum <5 clear, free of suspended matter clear, free of suspended matter 0.002 maximum <0.0001 0.02 maximum 0.0010 0.01 maximum <0.0001 0.5 maximum 0.03 12 to 13 12.2 to 12.4 0.922 to 0.925 0.922 SL 049064 However, most polysiloxanes are made with methyl or phenyl rather than ethyl groups. Solvent. As a chlorinated hydrocarbon, ethyl chloride can dissolve fats, oils, waxes and resins. It is especially potent for phos phorus and sulfur. Combined with methyl alcohol and benzene, ethyl chloride can dissolve nitrocellulose; combined with meth yl acetate, it can dissolve triethylcellulose. Ethyl chloride acts as a processing solvent in the polymerization of olefins with cat alysts such as aluminum chloride and titanium tetrachloride. Anesthetic. The rapid cooling effect of ethyl chloride as it vaporizes makes it use ful as a local anesthetic. Its narcotic action as a chlorinated hydrocarbon accounts for the capability of ethyl chloride as a general anesthetic. PPG Industries does not supply U.S.P.-grade ethyl chloride. HEALTH HAZARDS The threshold limit value (TLV) established in 1970* by the American Conference of Governmental Hygienists is 1000 parts per million. Vapor concentrations in work areas should not exceed this TLV as a timeweighted, average atmospheric concentra tion for an 8-hour day. Because of its narcotic action, ethyl chlo ride has been used as an inhalation anes thetic. Vapor concentrations as low as 1% by volume can produce narcotic and anes thetic effects. Concentrations of 4% or over may produce deep or even fatal anesthesia. Inhaled ethyl chloride is rapidly absorbed, but is also rapidly eliminated. Since the liquid evaporates rapidly, ethyl chloride could conceivably produce frost bite in contact with the skin. To some extent it is absorbed through the skin. The probability of hazard through skin absorp tion is remote. Ethyl chloride is slightly irritating to the skin and mucous mem branes. When ethyl chloride is decomposed by heat or ignition, hydrogen chloride gas, highly irritating to the nose and throat, is given off. More information appears in a Hygienic Guide Series Sheet, "Ethyl Chloride," pub lished by the American Industrial Hygiene Association, 25711 Southfield Road, Southfield, Michigan 48075, also in Chemi cal Safety Data Sheet SD-50 published by the Manufacturing Chemists Association, 1825 Connecticut Avenue, N. W., Wash ington, D. C. 20009. HANDLING AND STORAGE Ethyl chloride is a highly volatile, flam mable liquid. Mixed with air at ordinary temperatures, ethyl chloride vapors are ex plosive by ignition within the limits of 3.16 to 15% by volume. Fire and explosion hazards can be minimized by adequate ventilation, the proper types and arrange ment of equipment, and reasonable pre cautions and care in handling. Above its boiling point of 12.4 C (54F) ethyl chloride creates a pressure when con fined. It is shipped and handled in pres surized containers. Small containers should not be exposed to th sun's direct rays or to heat sources. Stainless steel is the preferred construction material for storage vessels, but ordinary steel may be used so long as a tank does not contain water as a separate phase. Prolonged contact between ethyl chloride and copper should be avoided. Information on the "Safe Handling and Use of Ethyl Chloride" appears in Chem ical Safety Data Sheet SD-50 mentioned above. PACKAGING AND SHIPPING PPG Industries delivers ethyl chloride by tank car and barge as the liquid under pressure. SAMPLES AND SERVICE Samples are shipped in small, pressurized metal containers of various sizes. The technical service staff of PPG Indus tries Chemical Division is available for con sulting on handling, storage and use. *Threshold limit values are reviewed yearly and are revised periodically. * -y t^ o O 4J .. 2 ^m S ? %O ' 3 fin ^o Or o o JO v 0 O SL *9oes A-1027 2.5M 471 Printed in U.S.A. i;i> ,,fS5I^?Ct t0 Protective Order of 14th Judicial District Court Ho. 91-1145 Vinylidene chloride monomer (VDC) is a versatile product used with other monomers to make a wide variety of copolymer resins and latices. Properly inhibited and protected from exposure to air, oxygen, water and light, VDC is stable in shipment and storage at ambient temperatures. Correct han dling practices, outlined below must be followed at all times. VDC supplied by PPG Industries' Chemicals Group from its Lake Charles, Louisiana, plant is inhibited with hydroquinone monomethyl ether (HQMME or MEHQ) to prevent polymerization during shipment and storage. It is shipped under a nitrogen blanket to avoid contact with air and to prevent the formation of a peroxide that can act as a polymerization initiator. For most applications, the MEHQ in hibitor in PPG vinylidene chloride need not be removed. If uninhibited monomer is required, however, the MEHQ can be removed by distillation or alkali extraction. GRADES The standard grade of VDC manufac tured by PPG is inhibited with hydroquinone monomethyl ether at ap proximately 200 parts per million. resistance, and impermeability to water vapor and gases. Data on reactivity ratios of VDC copolymerizations with 36 monomers are presented in a booklet, "Vinylidene Chloride Handling, Properties and Reactivity Ratios," Form A-967-120R, available on request from PPG Indus tries' Chemicals Group. HEALTH HAZARDS Acute overexposure to vinylidene chloride vapor by inhalation can lead tc anesthesia, irrational behavior, drunk- PROPERTIES Chemical Names: Vinylidene chloride; vinylidene chloride monomer; 1,1dichloroethylene Chemical Formula: CHjCa*; H^~<"'`C1 Molecular Weight 96.94. Contains 73.14% chlorine. Description: At ordinary handling temperatures, below its boiling point of 88.9F (31.6C), vinylidene chloride is a liquid. It is clear and colorless and has a sweet odor. Vinylidene chloride is highly volatile and its vapor is toxic and extremely flamma ble. Boiling Point, C +31.6 Critical Temperature, C 222 F Freezing Point, C +88.9 F -122.5 Absolute Viscosity at 20C, cps 432 FExplosive Limits, volume % in air ` -188.5 Specific Gravity, 20/20C 7 to 16 Density at 20C, pounds/gallon 0.330 1.213 Flash Point, Tag closed cup, C -30 Refractive Index, nu at 20C 10-1 F -5 1.4247 Autoignition Temperature, C 570.0 Vapor Pressure, mm Hg, at 20C F 1058 Solubility, water in monomer at 495 Critical Pressure, atmospheres 51.3 20C, weight % 0.035 USES Vinylidene chloride monomer has been used for many years, primarily as a copolymer with such monomers as vinyl chloride, vinyl acetate, acrylonitrile, and acrylic acid esters. The copolymer resins and latices are formed into films, fibers, coatings and linings. VDC imparts to finished products qualities of flame retardance, chemical Solubility: Reactivity: Vinylidene chloride is practically insoluble in water (0.04 weight % at 20C) but soluble in most organic solvents. Uninhibited, or inhibitor-depleted, vinylidene chloride may polymerize very slowly even in the absence of oxygen. To further retard polymerization, the uninhibited monomer should be maintained in darkness below 14F (-10C). Uninhibited, or inhibitor-depleted, vinylidene chloride re acts readily with oxygen or air to form a peroxide at temper atures as low as -40F or C. SL 049066 Specification and typical anaty8ia: Appearance Color, APHA Vinylidene Chloride, weight % (excluding inhibitor) Acetylene, as C2H2, ppm Specification clear, free of suspended matter 25 maximum 99.6 maximum Typical Analysis clear, free of suspended matter 5 99.9 25 maximum <1 Other Chlorinated Hydrocarbons, no one to exceed this weight % Acidity, as HC1, ppm Peroxide, as H202, ppm Water, ppm Inhibitor, HQMME*, ppm 0.25 maximum 10 maximum 10 maximum 50 maximum 180 to 220 0.1 <1 <1 30 200 'Hydroquinone monomethyl ether is sometimes referred to as MEHQ (monomethyl ether of hydroquinone). enness, and -- if continued -- to uncon sciousness and, ultimately, death. Vi nylidene chloride is highly volatile and its vapor is heavier than air. Since its odor threshold lies between 500 and 1000 ppm, the odor of vinylidene chloride is not an adequate warning to prevent overexposure. In all cases of overexposure, medical attention should be obtained. Vinylidene chloride is irritating to eyes and skin. The inhibitor, if not washed off promptly, can cause severe local irritation or burns. Chronic exposure to low concentra tions of vinylidene chloride can result in injury to the liver and kidneys. Also, in recent preliminary animal studies, it has been reported that vinylidene chloride vapor in concentrations higher than the present American Conference of Gov ernmental Industrial Hygienists (ACGIH) threshold limit value (TLV) of 10 ppm may be carcinogenic to some species of experimental laboratory ani mals via inhalation. Although these findings are preliminary and incomplete, PPG suggests that air concentrations of vinylidene chloride in the work area be maintained below 10 ppm at all times. PPG also recommends that the 8-hour time-weighted average (TWA) be main tained as far below 10 ppm as practical. HANDLING AND STORAGE If tank car valves are defective or leaky, do not unload. Telephone the PPG Industries Emergency Response Center at (304) 843-1300 in Natrium, West Virginia. This telephone is man ned to answer 24 hours a day. Nitrogen used in vinylidene chloride service should have a maximum oxygen content of 10 ppm. In a bulk storage tank, oxygen content should be kept below 100 ppm by volume. Information on unloading tank cars and drums, handling spills and leaks, construction materials, storage tanks and transfer lines is presented in a book let on "Vinylidene Chloride," Form A-967-120R, available on request from PPG Industries' Chemicals Group. Fire hazard Vinylidene chloride vapor is ex tremely flammable and burns vigorously at concentrations between 7 and 16% by volume in air. Proper ventilation and the elimination of ignition sources are mandatory in areas where vapor con centrations may reach a flammable level due to spills or leaks. Explosion hazard The peroxide compound that forms when uninhibited vinylidene chloride has been exposed to atmospheric oxy gen is potentially dangerous. This peroxide can also form if the inhibitor content has been depleted. Depletion can result from any of several causes in cluding distillation or exposure to o4B gen due to improper storage. The potSB tial presence of peroxide can frequently be detected by sharp, acrid odors or by the precipitation of a white flocculent polymer. Dried polymer residues may contain adsorbed peroxide which can be exploded by a slight mechanical shock or by heat. These residues should be handled with extreme caution. Adding water that is at room temperature to polymer residues containing peroxide renders them inactive. However, the hazard may return if the water evapo rates. The peroxide can be destroyed by several washes with a 5% by volume so lution of methanol in perchlorethylene. Any peroxide present as a precipitate in monomer can be destroyed by mixing with one part perchlorethylenemethanol solution and four parts vi nylidene chloride monomer. Separation and handling of precipitated polymer, and its potentially dangerous adsorbed peroxide, must be done with extreme caution. Contact either the PPG plant at Lake Charles or Technical Service Pittsburgh for additional informatic^B Equipment not used continually shoula be filled with water when shut down. PACKAGING AND SHIPPING PPG Industries ships vinylidene chloride (inhibited) in tank cars of 11.000- gallon (111,000-pound) and 20.000- gallon (190,000-pound) capac ity and in 55-gallon (500-pound) drums from Lake Charles, Louisiana. SAMPLES AND SERVICE Samples of vinylidene chloride are available on request in 1-pint and 5-gallon containers. The technical serv ice staff of PPG Industries' Chemicals Group is available for consulting on safe handling, storage and use. A-1001-120C 1M 179 Subject to Protective Order of 14th Judicial District Co*fadinU.S.A. No. 91-1145 TRICHLOROETHYLENE INFORMATION BULLETIN PPG has recently learned that a "Memorandum Of Alert" has been issued by the National Cancer Institute (NCI) stating that trichloroethylene was orally administered into the stomach of mice and these mice subsequently developed liver and other organ tumors. NCI, however, cautioned that "The information transmitted represents only a statement of concern and that no definite conclusions as to the carcinoaenicitv nf the substance may be reached until all of the data from the histopathology examinations have been received and evaluated." In interpreting these preliminary results, PPG feels that the animal species tested and the route of administration should be explained. The oral administration used required a stomach tube to be inserted in the animal and through this tube, trichloroethylene dissolved in corn oil was introduced into the stomach and the tube removed. This procedure was repeated daily, five days per week for 18 months. The dosage of trichloroethylene administered to the mice would be equivalent to a person drinking a six ounce glass of trichloroethylene (without corn oil) daily for the major portion of his life. The Occupational Safety And Health Standard for trichloroethylene is 100 parts per million (PPM) 8-hour time weighted average, 200 PPM acceptable ceiling concentration, and 300 PPM acceptable maximum peak above the acceptable ceiling concentration for an 8-hour shift not to exceed five minutes in any two hours. Since any possible worker exposure would most likely be through inhalation, it is apparent that exposure to the 0SHA Standard levels would not allow absorption of the levels of trichloro ethylene reported in the NCI studies. While PPG's exposure and monitoring data indicate levels well below 0SHA Standards, PPG is, nevertheless, examining existing exposure monitoring and reduction programs for trichloro ethylene. Through the MCA, PPG has initiated a meeting on May 12 with the other domestic and foreign producers of trichloroethylene to review existing information and to plan additional research programs related to the industrial environment. PPG is concerned about the NCI alert but is trying to place interpretation of the preliminary findings in reasonable perspective. We feel this infor mation should be immediately brought to the attention of our employees, customers, and distributors. You will be kept informed of future information obtained. ``/be 5/6/75 SL 0A9068 polyvinyl chloride product. From a public health standpoint, such bans are com pletely unnecessary and would serve only as meaningless gestures. Question: Did the PVC industry withhold important information on the health effects of vinyl chloride from the public? Answer: The PVC industry throughout the world has consistently acted in a respon sible manner with regard to the develop ment and dissemination of information on vinyl chloride. The industry has spon sor d the majority of the medical research on vinyl chloride conducted to date, and essentially all of it conducted before 1974, when the first tentative link between vinyl chloride exposure and angiosarcoma in humans was discovered by an industry doctor and publicly announced by his company. In fact, were it not for the ac tions taken by the PVC industry from 1970 onward, we might still know next to noth ing about the health effects of vinyl chloride. Question: Does vinyl chloride increase the risk of still births and miscarriages among the wives of heavily' exposed industry workers? Answer: While one recent research project at a single plant in Pennsylvania reported that such a risk may exist, serious sci entific questions have been raised con cerning the manner in which the study was conducted. It is clear that a more thorough scientific investigation of this subject will be required before any de finitive conclusions can be reached, in addition, since the research was con ducted, vinyl chloride exposure levels throughout the industry have been reduced a hundredfold or more. Even if a problem did exist, it has already bee$ eliminated. Question: Does vinyl chloride cause birth defects in communities with PVC facili ties? Answer: Because of a report from Ohio of excess birth defects in three widely separated communities with PVC facilities, the Center for Disease Control (CDC) of the U.S. Department of Health, Education and Welfare conducted its own two-part study--one part In Pennsylvania and the second in Ohio. CDC concluded, on the basis of these investigations and a thor ough analysis of the existing research data, that the evidence to date did "not establish any association between (birth defect) cases and vinyl chloride expo sure." i For Further Information Contact: i The Society of the Plastics Industry, Inc. 355 Lexington Avenue New York, New York 10017 i (212) 573-9400 O' vO O o 4 cn ' a' / t Jo PVC AND HEALTH QUESTIONS AND ANSWERS The Society of the Plastics Industry, Inc PVC AND HEALTH QUESTIONS AND ANSWERS Since early 1974, vinyl chloride, the gaseous industrial chemical from which polyvinyl chloride (PVC) plastic is made, has been the subject of widespread misunder standing regarding questions of occupational and public health. While a variety of errone ous and misleading impressions concerning vinyl chloride and PVC have been created in the public mind, the known facts, supported by extensive medical and technical research, are that: 1. The development of angiosarcoma of the liver, a rare form of cancer, from vinyl chloride exposure has been con fined exclusively to the occupational setting. 2. Angiosarcoma may develop only after the inhalation of substantial amounts of vinyl chloride over an extended period of time. 3. There is no evidence of hazard to the general public either from exposure to the minute amounts of vinyl chloride that may be found in the air around PVC plants, or from the use of finished polyvinyl chloride products. Following are some questions commonly asked about vinyl chloride and health. Answers are based on known scientific evidence and industry experience. Question: What is PVC and how is it used? Answer: Polyvinyl chloride or PVC is the sec ond most widely used plastic resin in the United States. It is produced from vinyl chloride gas by a process called poly merization. The resin is, in turn, fabricated into a wide vari^Baf consumer and in dustrial products^mcluding floor tile, cur tains, shoes, electrical insulation, tele phone equipment, medical-surgical de vices, phonograph records, food pack aging, upholstery, umbrellas and rain coats, luggage and sporting goods. Ap proximately 2.2 million American jobs are directly or indirectly dependent on the PVC industry. Question: How serious an occupational haz ard is vinyl chloride? Answer: Over the past 15 years, fewer than 20 deaths from angiosarcoma have oc curred among U.S. workers heavily ex posed to vinyl chloride gas. The workers' jobs principally involved cleaning residue of PVC resin from the reactors in which it was produced. While it can be expected that some additional deaths will occur in the future as a result of these heavy past exposures, with the strict control mea sures instituted over the last two years, there is every reason to believe that vinyl chloride related disease has already been eliminated as an occupational problem. Question: Is vinyl chloride a major air pol lutant? Answer: No. Measurements taken by the Federal Environmental Protection Agency (EPA) determined that, even in the past, the average exposure of individuals living in proximity to vinyl chloride gas and PVC resin plants was many times lower than that now considered to be safe for occu pational exposure. As a purely precau tionary step, new EPA regulations will further significantly reduce even this minimal exposure. In addition, the EPA has concluded that the potential public exposure from PVC faraQPRing plants is so minimal as to require no regulations what ever. Question: Does vinyl chloride cause disease in the general public? -P u n3 0) O rC, d in -r% 3Q rJl o Answer: No. A government survey of all angiosarcoma deaths in the United Stat s between 1964 and 1974 found no exc ss of deaths from this disease among people living within five mil s of vinyl chloride gas and PVC resin plants. The report con cluded: "This survey has produc d no evi dence that living around vinyl chloride plants is a risk factor in the occurrence of liver angiosarcoma." In addition, ther is no evidence whatsoever that any p rson has contracted this diseas from th use of finished PVC products, or from ing sting food or beverages packaged in PVC con tainers. Question: Is it safe to consume food or bev erages packaged in PVC? Answer. Yes. As a result of strenuous indus try efforts over the past few y ars, the residual vinyl chlorid cont nt has been reduced to "non-d t ctable" levels in < packaging products made from foodgrade PVC resins. Therefor , th r is no reasonable possibility of vinyl chlorid migration into foods, drugs, cosmetics or other products contained in such pack ages. Question: Should the manufacture and use of PVC products be banned? Answer: Vinyl chloride concentrations in the workplace, in community air, and in finished PVC products are being rigidly controlled, and there is therefore no reasbn to ban the manufacture or use of any Unloading and storage technique for vinyl chloride monomer The system described here is critical to the safe handling of this widely discussed carcinogen. c'O-*' O' v V-' Atu Mukerjt, Catalytic Itq* \\o* Q Numerous tests and consequent governmental reg ulations have established vinyl chloride monomer (vcm) as a dangerous carcinogen. * Manufacturers of vcm have accordingly modified plants to protect workers from contact with the chemical. In the changeover, one step has become critical to the overall process for converting toxic vcm to safe polyvi nyl chloride (pvc)--the loading step, where vcm from tank cars and tank trucks is loaded into a customer's storage tanks for processing to pvc. Since the polymeri zation plants are relatively smaller than vcm plants, and are dispersed near to their markets, the critical loading stations are many. Moreover, vapors from an empty vcm storage tank must be collected and contained as they are displaced by a new supply of liquid, because of stringent specifi cations as to permissible concentrations of vcm in the atmosphere. Still further, vcm is an explosion hazard, correspond ing to Class 1, Group D, Div. 1, of the National Electri cal Manufacturers Assn, code, nema 7, and variations in ambient temperatures at various locations complicate the outdoor unloading/loading problem. Vapor/liquid exchange The key to solving these problems consists of a vapor-liquid-exchange process, which has been incor porated into the design of a number of successfully operating unloading stations (Fig. 1). With this process, a compressor draws vapor from the plant's storage tank, and feeds the compressed vapor into a tank car, forcing vcm from the tank car up through a dip tube and into the transfer piping system. t Alternately, a slipstream of liquid vcm from the stor age tank is vaporized by steam to similarly increase tank-car pressure. The vaporizer generally comes into play either when the compressor is down for mainte nance or when ambient temperatures are too low (below 60 F) for the compressor alone to handle the unloading. Using the compressor, vcm transfer continues until the level in the tank car falls below the dip pipe, at which point the tank car is full of displaced vapors plus Chm. Eng.: May 13, 1974, p. 55; July 8, 1974, p. 28; Sept. 2, 1974, p. 23; Sept. 30,1974, p. 23; Sept. 30, 1974, p. 42; Feb. 17, 1975, p. 35; Mar. 17, 1975, p. 23; June 9, 1975, p. 36; Oct. 13, 1975, p. 67; Jan. 5, 1976, p. 74. residue liquid. This liquid can be transferred by con necting the compressor's suction to the tank car, and its discharge to the storage tank. A four-way valve in the suction and discharge lines effects this changeover without exposing the operator to vcm. With the normal compressor flow thus reversed, re sidual liquid in the tank car vaporizes from the reduc tion in pressure, while the compressed vapors are con densed in the storage tank by bubbling them through the large mass of liquid, which removes the heat of compression. In this manner, the tank car is normally evacuated down to the pressure required for reloading. Depending on the heat transfer into the tank car, residual liquid vaporizes within 20 to 30 minutes, dur ing which time the pressure will not be radically re duced. After the liquid has been vaporized, the time for evacuating the remaining vapors may be calculated with the formula: M = (V/DE) In (PJPt) where: M = evaporation time, min. V = tank-car volume, ft.3 D = compressor piston displacement, ft3/min. P1 = tank-car pressure at start of cycle, psia P2 = tank-car pressure at end of cycle, psia E = average volumetric efficiency of compres sor The economics of the evacuation operation can be evaluated according to the value of vcm. After the tank car has been completely evacuated, the compressor is used to evacuate the disconnected hose, which only then should be taken off for storage. The storage tank is emptied of vcm for maintenance by filling it with water as displaced vapors are vented to a monomer gas collecting system, and then letting in air through the atmospheric vent as the water is drained into the diked storage area for runoff to storm sewers. Unloading system The unloading system consists of transfer piping, compressor, vaporizer, storage tanks, and instrumenta tion for safety and control. Flexible metal hoses connect the tank car to the rigid transfer piping. Each transfer connection on the tank car contains an isolation valve and a built-in excess-flow valve to prevent leakage in 4 CHEMICAL ENGINEERING SEPTEMBER 12, 1977 SL 4907T 155 VINYL. CHLORIDE MONOMER * C ourt ,j in l: -=r ." i - C, 7o- 0 C "^ z ~ x- " the event of a ruptured hose. Similarly, the rigid piping contains check valves to prevent backflow from the storage tank in case of rupture. vcm inventory is measured by means of a turbine meter and a flow totalizer in the transfer piping. A filter upstream of the meter protects it from dirt, as well as extending the online time of the monomer-reactor charging filter (see Fig. 1). -r-', ^' Design criteria The steps in designing a vcm unloading system gen Oj erally take the following sequence: o 1. Establish the piping configuration for compressor, vaporizer, storage tank and tank car. 2. Determine the optimum transfer-line size for the desired flowrate. 3. Size and select the compressor. 4. Develop the detailed instrumentation. The piping configuration is made in accordance with o< the flowscheme (Fig. 1) and a physical layout for the unloading station. Pressure drops in the transfer lines must include static elevation and line losses between the compressor discharge and the tank car, and between the compressor suction and the storage tank. Also, pressure drops across the turbine meter, and a dirty filter, must be allowed for. Since the entire unloading area will be outdoors and may be in northern climates, the compressor and va porizer design must allow for seasonal temperatures such as 110, 60, and 10 F, corresponding to monomer vapor pressures of 95, 43 and 11 psia, respectively. A common practice is to size the compressor for spring conditions, relying on the vaporizer to augment transfer during the winter. In this case, the compressor will unload during summer at a much faster rate, whiclfl can be calculated by trial and error, assuming a flowrate and working backward through the compressorsizing calculations. CHEMICAL ENGINEERING SEPTEMBER 12. 1977 These calculations determine the required compressor displacement, as a function of its volumetric efficiency, the vapor molecular weight, vapor density and specific heat, the discharge and suction temperatures and pres sures, the unloading rate, and the heat lost by the tank car to its surroundings (see box, p. 160). The vaporizer is essentially a vapor/liquid separator with a steam-heated chamber. Liquid vcm flow to this vessel is about one thirtieth of the liquid transferred from the tank. Vaporizer design is based on winter conditions, the worst case for unloading vcm. Operating pressure is the sum of the storage tank pressure and the pressure losses in the transfer line. Liquid entrainment in the vapor can be minimized by introducing a wire-mesh screen to coalesce the liquid droplets, and by providing sufficient disengaging height above the liquid surface. The required mass flowrate of vcm vapor to the tank can be taken from compressor calculations for winter conditions. This figure, along with the liquid and vapor densities of vcm at operating pressure and temperatures, gives the volumetric vapor flowrate to the tank car, and the liquid flowrate to the vaporizer. The remaining vaporizer design calculations deal with steam require ments and heat-transfer surfaces. Instrumentation All locally mounted electronic instruments must meet the Class 1, Group D, Div. 1 requirements of nema 7. Electronic, intrinsically safe, explosion-proof instru ments are available from most vendors, for on-the-spot calibrating and troubleshooting, if required. Also, electronic instruments should be capable of withstanding seasonal temperature extremes. Other wise, heaters or coolers must be used. Pneumatic local instruments should be weatherproof and dust-tight. The totalizer, used with the turbine meter in the transfer line, displays the instantaneous vcm flowrate in CHEMICAL ENGINEERING SEPTEMBER 12. 1977 SL 049073 157 VINYL CHLORIDE MONOMER -jSSS~ --`'4:?---;4-, Connect tank car to unloading nation rjki Select norage tank Ret bv Doaitioning tank "STB unloading `"*1 fill telector twitch - Sis meter to zero , JS! --- --;---- T--TtiE-JTg^ -* --t ' . .i - -*3WW^5r| Align 4-wey valve j in the Itrantfer line * "-V. ,, - J*2?*3#0 `^4i ' yjrt&JT- ?*-. --awB.1 j With previous L | approval, start | unloading compressor ^yv, WrxevJr*, , v.,.;4r | Check level 1 in knock-out pot by [ level gauge Open steam supply valve to /tracer on knock-out pot Observe liquid level in knock out pot ' Monitor unloading rate on totalizer, during unloading 6,;. 3A.*/, ` 9 -.-fr .*4' . Restart unloading compressor `mri iik`, !?>W y t Check storage tank level on level indicator High-level alarm on Select next J storage tank . I with previous | approval Align valving / Restart unloading I compressor I f Compressor malfunction; i obtain approval to start second compressor Align valving , between storage . I tank, compressor and tanx car I Check liquid level I in compressor suction knock- out pot IV". ''-A&i - > -!-> -- Operating diagram for unloading vinyl chloride tank car Start unloading compressor Report to shift foreman Fig. 2 ... *-> ..3 w gpm, and accumulates the actual vcm removed on both a resettable batch counter and a continuous counter, in order to be able to display vcm unloaded from several tank cars after a period of time. The batch counter reading is logged after unloading each tank car, and reset before unloading the next. To compute a material balance, a reactor batch charge, and a reaction conversion, the operator must know the total weight of vcm unloaded into the storage tanks. Since the density of unloaded vcm varies with ambient temperature, a temperature-compensated flow measurement is required. The turbine meter affords an accuracy of 0.15 to 0.25% of the instantaneous flow. For such accuracy, the meter vendors must have density and viscosity data for seasonal conditions. Also, the transfer line must provide straight runs of 15 pipe diameters upstream and 5 pipe diameters downstream of the meter. The totalizer should have built-in low-flow and high-flow switches. The low-flow gives indication when (1) the filter ahead of the meter is plugged, or (2) the manual valves in the transfer line are blocked, or (3) the compressor is malfunctioning. The high-flow protects the turbine meter from overspeeding due to vapor flow, by stopping the compressor. Vapor flow occurs when the liquid level in the unloading tank car drops below the dip pipe. Overspeeding the turbine reduces the life of its bearings and may damage the rotor. Even after the compressor stops, vapor flow will continue until the tank car and storage tank have achieved the same ---------------------- SL 049074 158 CHEMICAL ENGINEERING SEPTEMBER 12, 1977 C.i 4<Q * pressure, which can introduce significant error in the totalized reading. This vapor flow can be avoided by placing an auto matic on-off valve, actuated by a density-difference or pressure switch, at the tank-car end of the transfer line. The level indication on a storage tank permits sched uling that tank for reloading and production, whether the tank has enough material to charge a reactor batch or whether a tank car's contents can be unloaded into it. Magnetic and capacitance-type level meters provide a reading unaffected by the varying vcm density. Read ings that depend on liquid pressure, on the other hand, will vary with ambient temperature. A high-level switch interlocked with the storage-tank unloading pumps prevents cavitation by maintaining enough liquid head at the pump suction. In the event of fire, an automatic fire-valve on the storage tank's discharge line isolates the tank. Normally, a fire-safe full-port ball valve with pneumatic actuator serves for this purpose. The fire detector can be a bimetallic switch set at 170F near the fire valve. A relief-valve/rupture-disc combination protects the stor age tank from overpressure due to fire or overfilling. A redundant relief system on each tank prevents acciden tal shutdown. A self-actuated excess-flow valve downstream of the fire valve isolates the storage tank in case of line rup ture, or failure of the reactor charge-valve, or an instru ment malfunction in the vcM-reactor charging system. Fire and excess-flow valves are close-coupled to the storage tank and interlocked with the storage-tank un loading pump to prevent evacuation of pump suction lines with these valves closed, and thereby prevent over heating the pump. For multiple storage-tanks using several unloading compressors and unloading pumps, the installation re quires multiposition selector-switches to facilitate auto matic interlocking of the selected tank instruments with the pump and compressor in use. Instrumentation for the compressor includes gages to display discharge pres sure, and a relief-valve/rupture-disk combination to protect positive-displacement compressors. It is not good practice to pipe the discharge of this valve to the compressor suction, because of possible overheating due to continuous recirculation and recompression. A liquid trap on the compressor suction side mini- CHEMICAL ENGINEERING SEPTEMBER 12, 1977 SL 049075 159 VINYL CHLORIDE MONOMER mizcs chances for slugs of liquid to reach the compres sor. A high-level switch in the liquid trap is interlocked to shut down the compressor, and the trap is steamtraced and insulated to reduce the accumulation of liquid. Instruments for the compressor and liquid traps generally come as part of the compressor package. Pres sure and level controls on the vaporizer aid the unload ing operation by maintaining heat and material bal ances, respectively. Pressure is maintained through the 0 heat input to the vaporizer, and the level is held con stant by liquid vcm flow. : ; Since the vaporizer operating pressure is higher than the storage-tank pressure, the storage-tank unloading ' tri pumps must supply a slip-stream of chloride to the v: vaporizer. Possible cavitation damage to the level-conP'. trol valve can be eliminated by means of a valve with a ^ high recovery coefficient or anticavitation trim. " , A relief-valve/rupture-disk combination protects the ; ; _ vaporizer from overpressure due to fire, or steam-valve o or level-valve failure. The steam valve is interlocked - " , " with the high-flow cutoff switch of the unloading system p protecting the turbine meter. !7` -C, Safety Area monitors are located at breathing level in the M-l o work areas to detect vcm emissions. Since vinyl chloride vapor is heavier than air, it has a tendency to move downward, so detectors for combustible gases should be located at an elevation of 2% ft, near the sources of possible vcm vapor leaks. vcm concentration, measured in ppm by a chromato graph, is displayed, and an alarm sounds, when this concentration exceeds 75% of maximum permissible. vcm concentration as a percentage of vcm's lower ex J plosive limit is also displayed, monitored ancP alarmed--as measured by a remote combustibles ana lyzer, Because of the distance between the polymeriza tion-reactor control room and the unloading area, it is usually convenient to group controls and instruments for vcm unloading on a nearby water- and dust-tight control panel. The control room operator needs only the critical data for overall coordination--such as storage tank level; and the status of the unloading compressor, the fire and excess-flow valves, and the unloading pump. A remote pushbutton can be interlocked with all the fire valves on storage tanks, in order to close those valves in an emergency. Relief valves protect the transfer piping from thermal expansion wherever liquid can be blocked between valves. The blinded vent on the storage tank is equipped with a flame arrester to prevent flash-back The author Ami Mukeqi is a senior instrument engineer with Catalytic, Inc., 1500 Market Street, Philadelphia, Pa. 19102, where he has served as lead instrument engineer for a variety of project*. He has had prior design ana application experience with an instrument manufacturer in India. He holds an M.S. degree from Drexel University and a B.S. degree from the Indian Institute of Technology, Bombay, in chemical engineering. 160 CHEMICAL ENGINEERING SEPTEMBER 12, 1977 SL 049076 Su'vj