Fire, Explosion, Leakage Place Quantitative Safety Assessment Methods And Consequences Of The Accident Analysis

The enlargement of equipment scale and the continuity of manufacturing process have become the development orientation of today' s chemical industry, which make the evaluation of grave accidents holding the balance. In order to reduce the harm caused by accidents, researchers have analyzed the accidents already happened and summarized many safety evaluation methods and forecast model of grave accidents.Aiming at the fatalness of the places fire, explosion or leakage accidents occur, this paper studied the ration methods of safety evaluation and compared them as well. Through analyzing the consequences of applying two common ration methods of safety evaluation to the same unit or a single method to different units in the course of studying both of them, their differences and qualifications then can be gained consequently. Simultaneously, combining computer technology with the analyses of fire, explosion, and leakage-diffusion models, a simulation program based on Visual Basic 6. 0 have been developed in this paper which also discussed the scope and its diversification of harmfulness caused by fire, explosion and leakage-diffusion accidents under different conditions. All of the above have offered more practical evaluation method, pertinent succor measures of emergent accidents, and scientific bases and references of controlling and dealing with accident scenes effectively.Conclusions of this paper are listed as follows:1. ICI/MOND Fire Explosion Toxicity Index should be recommended when it comes to such units as fire accidents coexisting with dangers of explosion and toxicity.2. ICI/MOND Fire Explosion Toxicity Index should be recommended given that the main substances of the unit are of great toxicity and concrete evaluation on the harmfulness of the toxicity is necessary.3. Dow's fire and explosion hazard index should be recommended if the main substances of the unit are of little toxicity and concrete evaluations are needed on the range, loss and delay caused consequently.4. As for continuous leakage of toxic gas, since its approximate elliptical scope ranges according to the speed of the wind, the tendency of the scope varies as follows: multiply in small range,and then diminish gradually.5. As for instantaneous leakage of toxic gas, since its scope is a cluster of gas moving towards the direction of the wind, the tendency of the scope varies as follows as time goes by: the scope with little or middle harmful ness multiply first, then the latter exceeding the former diminish gradually, and disappear at last.6. After the BLEVE accidents, the main harm comes from the radiation made by the explosion, and the harm caused by shock waves is relatively small by contrast.7. In order to avoid BLEVE accidents and reduce the rate of accidents, we should start with such aspects as collective allocation, measures concerning fire and explosion proofing and security managing system as well.