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Bhopal Gas Tragedy case study

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Text of Bhopal Gas Tragedy case study

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2. Preview-Amongst the worst Industrial Disasters ofits time. Occurrence: 3rd December 1984. Place of occurrence: Bhopal, MadhyaPradesh, India. Company: Union Carbide Corporation. Chemical: Methyl Isocyanate (40 tons) People Affected- >500,000 People Died- ~40,000 3. About 550,000 people were exposed to the gas. A government affidavit in2006 stated the leak caused 558,125 INJURIES including 38,478TEMPORARY PARTIAL INJURIES and approximately 3,900 SEVERELY ANDPERMANENTLY DISABLING INJURIES 4. Bhopal ScenarioUnion CarbideCorporation Plant 5. About Union Carbide Corporation(UCC) Started in 1969 in bhopal Phosgene, Monomethlyamine, Methyl Isocyanate(MIC) and the pesticide carbaryl, also known as Sevin. Taken over by DOW Chemicals in 2001. DOW refused Union Carbides Liabilities in Bhopal,India. 6. All safety system fails due to poor maintenance. 7. Gas Vent Scrubber Gas Vent Scrubber Stack 8. MIC STORAGE TANKPicture shows the tank as it is today. 9. TANK SAFETY FEATURES A Nitrogen line was connected to the tank to transfer the product byinert pressurization of the headspace. The tank was fitted with a pressure relief valve and rupture disc. Thevent line from the valve exhausted into a scrubbing tower filled withcaustic soda (NaOH). This would neutralize the MIC to form Sodiumisocyanate. Any residual gas from the scrubber was sent to a 30 m tallflare stack where it would be burned off. There was an external coiled jacket on the vessel through which coolant(freon / chloroform) was re-circulated. This was to keep the vesselcontents at 0 C and thus prevent any adverse exothermic reactionsoccurring. Tanks were not to be filled above the 50 % mark so that in the event ofdangerous chemical reactions occurring, solvents could be pumped in toquench the reactions. 10. ACCIDENT DESCRIPTIONPipe Cleaning ProcedureAs part of routine procedures, the pipes leading from the MICdistillation column to the storage tanks were regularly flushed withpressurized water. MIC and any associated products can be quitecorrosive and could form corrosion deposits in the pipe. These depositswould contaminate the MIC in the tanks and could initiate unwantedreactions. During cleaning, valves in the product lines were to be closedand a blank or slip-blind placed in the product line leading to the storagetank to prevent contamination.However the valves, although closed, were not sealing properly becauseof corrosion and the maintenance crew forgot about the blank. Itappears that about 1000 kg of water plus metal debris entered tank 610.Assuming all the previously described safety features were operative,this should not have been a catastrophic occurrence. 11. Effects on Human Health. Respiratory Disorders Irritation to the lungs, causing coughing and/or shortness of breathing. Higher exposure caused build up of fluids (pulmonary enema). Caused Asthma. Cancer Hazard Caused mutation (genetic changes). It caused cancer. Reproductive Hazard Association between exposure to Methyl isocyanate and miscarriages. It may damage the growing fetus. May also affect fertility in men and women. After Effect- Traces of many toxins were found in the Brest Milk of mothers and were in turn transmitted to the recipient babies. 12. Animal Slaughter 2,000 buffalo, goats, and other animals died. 13. Toxic Materials in Soil and Water Lead, Nickel, Copper, Chromium,hexachlorocyclohexane and chlorobenzenes werefound in soil samples. Mercury was foundto be between20,000 to 6,000,000times the standardlevel in soil. 14. Chemicals Dumped by Union Carbide in Bhopal S.No Chemical Amount Use in factory Nature of original pollution 1Methylene Chloride 100 MT SolventAir 2Methanol 50 MTSolventAir 3Ortho-idichlorobenzene 500 MT SolventAir, Water, Soil 4Carbon tetrachloride 500 MT SolventAir 5Chloroform 300 MT SolventAir 6Tri methylamine50 MTCatalyst Air 7Chloro benzyl chloride 10 MTIngredient Air, Water, Soil 8Mono chloro toluene10 MTIngredient Air, Water, Soil 9Toluene20 MTIngredient Air, Water, Soil 10 Aldicarb 2 MT ProductAir, Water, Soil 11 Carbaryl 50 MTProductAir, Water, Soil 12 Benzene Hexachloride 5 MT Ingredient Air, Water, Soil 13 Mercury1 MTWater, Soil 14 Mono methyl amine25 MTIngredient Air 15 Chlorine 20 MTIngredient Air 16 Phosgene 5 MT Ingredient Air 17 Hydro chloric acid 50 MTIngredient Air, Soil 18 Chloro sulphonic acid50 MTIngredient Air, Soil 19 Alpha Naphthol * 50 MTIngredient Air, Soil 20 Napthalin50 MTIngredient Air 21 Chemical waste Tar 50 MTWasteWater, Soil 22 Methyl Isocyanate5 MT Ingredient Air, Water, Soil 15. Haphazard dumping of Hazardous Material 16. Toxic materials found in Soil and Water afterthe accidentBenzene, oxides 7, 890Dichlorobenzenes87,500Polynuclear Aromatic2,340HydrocarbonsPhthalates9,940Trichlorobenzenes 9,410Trimethyl Trianzintrione24,4701-Napthalenol 59,090Units in parts per billion (ppb)Additionally, Dichlorobenzene and Trichlorobenzenes were found inthe soil and water samples. 17. Compensation and Legal Aspects Compensation of $470 million ($500 per dead). Twenty years of passiveness. Case was reviewed and put up in American Court. DOW Refused Union Carbides Liabilities in Bhopal,India. In order to provide safe drinking water to thepopulation around the UCIL factory, Government ofMadhya Pradesh presented a scheme forimprovement of water supply. Supreme court directed the UCC and M.P. govt. totake immediate steps for disposal of toxic waste lyingaround and inside the factory. 18. 20,000 KILLED550,000 SEVERELY AFFECTED And you thought only weapons could cause Mass Destruction.