CHEM3001 – Case Study Nicola Broun 21151388 Seveso Accident Background In the town of Seveso 25 km from Milan, the ICMESA factory (based on Swiss company Givaudan) was responsible for the manufacture of 2,4,5-trichlorophenol (TCP), a herbicide (Lees and Mannan, 2005). The reaction process normally required a time frame of approximately 14 hours (Sambeth, 1983). This process involves the alkaline hydrolysis of 1,2,4,5 – Tetrachlorobenzene in Ethyleneglycol solvent. Xylene is also added to the reaction mixture to remove any water that is produced. The sodium 2,4,5-trichlorophenate product is distilled to remove the solvents, acidified and purified by fractional distillation to produce TCP (Lees and Mannan, 2005). The Accident Production commenced on the 9th July as per normal, with 1,2,4,5,-Tetrachlorobenzene (2 000kg), sodium hydroxide (1 050 kg), Ethyleneglyol (3 300kg) and Xylene (600kg) (Sambeth, 1983). It was a requirement for the chemical plant to shut down for the weekend, with the final shift concluding at 6am on Saturday morning (Sambeth, 1983). Due to this, the reaction was interrupted but not terminated on Saturday morning. If 50% of the Ethyleneglyol had been distilled by 5am (as it normally was), the reaction would have been cooled to 50-60⁰C by quenching it with 3000 litres of water, instead heating and stirring was turned off completely and the reaction mixture was left at 158⁰C (Sambeth, 1983). This decision was made because the distillation procedure was only 15% complete at the time and there was no known dangers for TCP at 158⁰C (Sambeth, 1983). At 12:37 pm, six and a half hours after the reaction had been stopped, the safety disk that was responsible for withstanding high pressures gave way, releasing... ... middle of paper ... ...ds, and an emergency evacuation plan for surrounding areas. References Sambeth, J, 1983. The Seveso Accident. Chemosphere, Volume 12, Issue 4-5, pp. 681-686. Available at: http://www.sciencedirect.com.ezproxy.library.uwa.edu.au/science/article/pii/0045653583902278#[Accessed 14 March 2014]. Fortunati, U, 1985. The Seveso Accident. Chemosphere, Volume 14, Issue 6-7, pp. 729-737. Available at: http://www.sciencedirect.com.ezproxy.library.uwa.edu.au/science/article/pii/004565358590181X# [Accessed: 14 Mar 2014]. Lees, F. P. and Mannan, S. 2005. Lee's loss prevention in the process industries. Third Edition. Burlington, MA: Elsevier Butterworth-Heinemann. Ec.europa.eu. 2014. Chemical Accidents (Seveso II) - Prevention, Preparedness and Response - Environment - European Commission. [online] Available at: http://ec.europa.eu/environment/seveso/ [Accessed: 14 Mar 2014].
Herndon J. M, 2005, Current Science, Scientific Basis of Knowledge of Earth’s Composition, 88, 1034-1036)
Plummer, C.C., McGeary, D., and Carlson, D.H., 2003, Physical geology (10th Ed.): McGraw-Hill, Boston, 580 p.
Fries, A. A., & West, C. J. (1921). Chemical warfare,. New York [etc.: McGraw-Hill book company, inc..
Catherine A. McCammon; Mantle Oxidation State and Oxygen Fugacity: Constraints on Mantle Chemistry, Structure, and Dynamics; Bayerisches Geoinstitut
The Saturate Gas Plant suffered heavy damages as a result of the incident and the explosion. Buildings normally occupied at the Refinery up to 400 metres away from the SGP were badly damaged. Fortunately, there were no people in the direct path of the gas cloud that caught on fire and exploded at the SGP or in the buildings such as the Canteen at the site, which would have been usually
Liukkonen, Petri. “Robert Graves (1895-1985).” Kirjasto.sci.fi. Ari Pesonen, Kuusankasken Kaupunginkirjasto. 2008. Web. April 2, 2011.
...Hallert, C., C. Grant, S. Grehn, C. Grannot, S. Hultent, G. Midhagens M. Strom, H. Svensson,
Arias, Mercedes L. University of Minnesota Driven to Discover. Ed. Kelley Hopler. N.p., 26 June 2009. Web. 11 Apr. 2011. .
A single slip in action may cause lasting sorrow. A slight mistake in operation at a Union Carbide pesticide plant in Bhopal of India causes a lot of deaths and injuries. What a tragedy it is. Undoubtedly, there must be something wrong with the management of the plant.
The factors that caused the series of events to happen and the dangers were foreseeable and could have been prevented. The ICMESA plant was property of Givaudan S.A., which was located in Geneva, Switzerland. ICMESA produced the intermediate compounds that Givaudan needed to produce its cosmetics, pharmaceuticals, and soaps. The compounds produced at this plant ranged from benzyl chloride and cyanide to phenylacetic acid and TCP [4]. The reaction of interest was the one that produced TCP, which was commonly used in surgical soaps. This was not the first plant that produced TCP that had an accident, but it was the first one that severely affected the villages surrounding the plant. TCP was already known to be toxic in its surgical soaps and was already banned from being used in the USA [1]. Though there were rumors about the safety of TCP at the time, TCP itself is only moderately toxic. The real culprit of the toxicity that was experienced in these soaps was a byproduct called 2,3,7,8-tetrachlorodibenzo-para-dioxin (TCDD, but commonly referred to as dioxin). This compound was significantly more toxic than TCP, but not very much else was known about the compound before the Seveso Disaster.
In 1938, iodine-131 and cobalt-60 isotopes were discovered by J. Livingood and G. Seaborg. 2
Environmental hazards arise as well from hazardous materials and waste. Hazardous materials concerns could arise from spills of gasoline, diesel fuel, oil, or solvents from containers or vehicles. Spills could contaminate soils or leach into ground or surface water. And environmental hazards could adversely affect humans, wild life, vegetation and water supply.
The bromine and fluorine in these chemicals act as catalysts, reforming ozone (O3) molecules and monatomic oxygen into molecular oxygen (O2). In volcanic eruptions, the sulfate aerosols released are a natural cause of ozone depletion. The hydrolysis of N2O5 on sulfate aerosols, coupled with the reaction with chlorine in HCl, ClO, ClONO2 and bromine compounds, causes the breakdown of ozone.
It is now commonly known, in the scientific community, that the movement of the Earths crust has been active for billions of years. However, the driving mechanism of tectonics forces still remains a mystery. The asthenosphere on which the lithosphere floats is molten due to radio-active decay warming us from the inside out. Volcanism is one result of moving plate margins. Specifically where plates spread apart, volcanoes and subsequently some of the largest mountain ranges on earth can be found. Hydrothermal vents are also founds at these location. What wasn’t understood until this dive was a hydrothermic cycle that created emense chimneys out of dissolved minerals and metals. There is absolutely no light for photosythesis, intense pressure from the miles of seawater above and the resultant freezing temperatures would seemingly inhibit life. However, it is only around these vent fields in which an amazing amount of diverse biomass can be seen.
Kinard, William H. "Technical Discipline Area: Materials." Long Duration Exposure Facility (LDEF) Archive System. NASA Langley Research Center, 04 Apr. 2001. Web. 21 Apr. 2014.