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Bhopal gas tragedy

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The truth behind Bhopal Gas Tragedy.

Text of Bhopal gas tragedy

  • 1. The legacy of disappointments Vivek Kumar, St. Vincent Pallotti College of Engineering and Technology, Nagpur

2. On 3rd December 1984 a rolling wind carried a poisonous grey cloud over to the streets of Bhopal around midnight. The devastation that occurred is said to be the Hiroshima of chemical industry 3. 2500 DEATHS IN 48 HOURS 85000 AFFECTED 5 Lac EXPOSED PLANTS, ANIMALS, FISHES.. ..NO ONE IS SPARED 4. The affected area 5. Union Carbide India Ltd. UCIL was the Indian subsidiary ofUnion CarbideCorporation (UCC). Indian Government controlled banks and the Indian public held 49.1% ownership share. In 1994, the Supreme Court of India allowed UCC to sell its 50.9 percent share. The Bhopal plant was sold to McLeod Russel (India) Ltd. UCC was purchased byDow Chemical Companyin 2001. 6. Location of the plant In close vicinity of the residential area. 7. The tank today.. 8. What caused the gas leak? An initial investigation by Union Carbide experts showed that a large volume of water had apparently been introduced into the methyl isocyanate (MIC) tank. This caused a chemical reaction that forced the pressure release valve to open and allowed the gas to leak. A committee of experts working on behalf of the Indian government conducted its own investigation and reached the same conclusion. An independent investigation by engineering consulting firm Arthur D. Little determined that the water could only have been introduced into the tank deliberately, since process safety systems -- in place and operational -- would have prevented water from entering the tank by accident. 9. Leakage & its immediate effects... In November 1984, most of the safety systems were not functioning and many valves and lines were in poor condition. In addition to this, several vent gas scrubbers had been out of service as well as the steam boiler, intended to clean the pipes was non-operational. 10. When water entered the tank no.610 containing about 42 tons of MIC . A runaway reaction started, which was accelerated by contaminants, high temperatures and other factors. The reaction was sped up by the presence of iron from corroding non-stainless steel pipelines. The resulting exothermic reaction increased the temperature inside the tank to over 200 C (392F) and raised the pressure. This forced the emergency venting of pressure from the MIC holding tank, releasing a large volume of toxic gases. About 30 metric tons of methyl isocyanate (MIC) escaped from the tank into the atmosphere in 45 to 60 minutes. 11. Why didnt the plants safety systems contain the leak? Based on several investigations, the safety systems in place could not have prevented a chemical reaction of this magnitude from causing a leak. In designing the plant's safety systems, a chemical reaction of this magnitude was not factored in for two reasons: 1. The tank's gas storage system was designed to automatically prevent such a large amount of water from being inadvertently introduced into the system; and 2. Process safety systems -- in place and operational -- would have prevented water from entering the tank by accident.The system design did not, however, account for the deliberate introduction of a large volume of water by an employee. 12. The gas cloud The gases were blown in south eastern direction over Bhopal. As of 2008, UCC had not released information about the possible composition of the cloud. Apart from MIC, the gas cloud may have contained phosgene, hydrogen cynide, carbon monoxide, hydrogen chloride, oxides of nitrogen, mono methyl amine (MMA) and carbon dioxide, either produced in the storage tank or in the atmosphere. The gas cloud was composed mainly of materials denser than the surrounding air, stayed close to the ground and spread outwards through the surrounding community. The nature of the cloud is still discussed. The chemical reactions would have produced a liquid or solid aerosol with high density. The concentrations at ground level would have been much higher than earlier published. 13. Acute effects Reversible reaction of glutathione (top) with methyl isocyanate (MIC, middle) allows the MIC to be transported into the body 14. Hydrogen cyanide debate Whether hydrogen cyanide(HCN) was present in the gas mixture is still a controversy. Cyanide concentrations of 300 ppm can lead to immediate collapse. The non-toxic antidote sodium thiosulfate (Na2S2O3) in intravenous injections increases the rate of conversion from cyanide to non-toxic thio cynate. Initial reports based on the autopsies of victims' bodies suggested cyanide poisoning based on which UCC's Dr. Bipan Avashia advised amyl nitrate and sodium thiosulphate. Treatment was tentatively used on some people, with mixed results. Critics argue that both the Government and Union Carbide tried to avoid mentioning the emotionally provocative word "cyanide." 15. Exposed to high temperatures, MIC breaks down to hydrogen cyanide (HCN). According to Kulling and Lorin, at +200C, 3% of the gas is HCN. However, according to another scientific publication ,MIC when heated in the gas-phase starts to break down to hydrogen cyanide (HCN) and other products above 400C. Chemically, HCN is known to be very reactive with MIC. HCN is also known to react with hydrochloric acid, ammonia, and methylamine (also produced in tank 610 during the vigorous reaction with water and chloroform) and also with itself under acidic conditions to form trimers of HCN called tri azenes. Laboratory replication studies by CSIR and UCC scientists failed to detect any HCN or HCN-derived side products. None of the HCN-derived side products were detected in the tank residue. 16. UNION CARBIDES VERSION A disgruntled plant employee, apparently bent on spoiling a batch of methyl isocyanate, added water to a storage tank. -------B. Browning Jackson (Vice President) 17. In order to provide safe drinking water to the population around the UCIL factory, Government of Madhya Pradesh presented a scheme for improvement of water supply. In December 2008, the Madhya Pradesh High Court decided that the toxic waste should be incinerated at Ankleshwar in Gujarat, which was met by protests from activists all over India.[ On 8 June 2012, the Centre for incineration of toxic Bhopal waste agreed to pay 250 million (US$4.0million) to dispose of UCIL chemical plants waste in Germany . On 9 August 2012, Supreme court directed the Union and Madhya Pradesh Governments to, take immediate steps for disposal of toxic waste lying around and inside the factory within six-month. 18. A US court rejected the law suit blaming UCC for causing soil and water pollution around the site of the plant and ruled that responsibility for remedial measures or related claims rested with the State Government and not with UCC. In 2005, the state government invited various Indian architects to enter their "concept for development of a memorial complex for Bhopal gas tragedy victims at the site of Union Carbide". In 2011, a conference was held on the site, with participants from European universities which was aimed for the same. 19. THE AFTERMATH There are no words for this . 20. THE AFTER-EFFECTS 21. The testimony of a Bhopal Municipal worker I used to pick up unclaimed dead bodies from the mortuary, I was used to doing it. That night (3rd December 1984) I putin thousands of bodies that we dumped - in one grave we would put 5-6bodies, and we burnt piles and piles with logs. Many bodies were burntun indentified - Muslims were burnt and Hindus were buried. We would fit 120 bodies in one truck and this we would fill and emptyfive times a day. There were eight trucks on duty (so that is 4,800bodies a day). It carried on for exactly the same intensity for three tofour days, the bodies had allturned blue.. 22. "At least 15 - 20,000 people died in those first few days. What theysaid in the papers was absolutely wrong. What could I have done? I was agovernment servant. What the government said was absolutely wrong. but,what could I do..?? 23. The continuing medical nightmare of Carbide's victims From what do the gas survivors in Bhopal suffer? In the districts nearthe factory, people are wracked by breathlessness, blurred vision,aching limbs and backs; numb limbs; there are monstrous births; children suffer from recurrent fevers and coughs; even young adults aredeveloping cataracts and feel constantly exhausted, with no appetiteeither for food or for life; Carbide's gases have added depression and anxiety to their already hard lives. 24. The continuing medical nightmare of Carbide's victims Its estimate that there are between 120,000 to 150,000 people still ill in Bhopal ie. suffering from chronic,disabling conditions which in many cases do not permit them to work, sothey are wretchedly underfed and this further exacerbates their healthproblems. 25. The continuing medical nightmare of Carbide's victims. The people living near the abandoned factory - where piles of dangerouschemicals lie in the open air to this day are obliged to drink water heavily polluted with Sevin residues, 12volatile organic chemicals, heavy metals and mercury millions of timeshigher than recognized safety limits. The water makes people ill, withthe same kind of symptoms as those who had been exposed to the gas in1984. Here too, the death toll is high. And the real pollution feedingthe local aquifers lies under the ground, where around a thousand tonnesof numerous chemicals were routinely dumped during normal operations at the factory prior to the gas leak. 26. What caused this disaster. 1] Factory Siting A plant producing a variety of very dangerous compounds was sited: a) too close to a residential area b) on the wrong side with respect to the prevailing wind. 2] Large Product Inventory Total storage capacity of MIC was in excess of 150 m3 . When dealing with such toxic products, the amount at hand should always be minimized. 27. 3] Abandonmen