| With China’s sustained and rapid economic and social development, people buy cars rigid demand, car ownership continue showed a trend of rapid growth, form a complete set of gas stations. This topic is based on the core of the "build" scene with three kinds of methods to analyze three scenarios(ARAMIS is used to study gas pipeline leakage accidents, using software was used to simulate gas leaks, use CFD software to simulate the sewer chain of gasoline vapor cloud explosion scenes) and the following conclusions:(1)Based on research of 140 refueling station accident cases and establishment of the bow-tie of critical event for gas pipeline leakage, the critical event risk severity obtain from probability(determined by FTA) and risk disaster consequence level(concluded from the analysis of ETA). And in consideration of vulnerability analysis(fully evaluation personnel,construction, environmental vulnerability), the thesis finally get the gas pipeline leakage risk value of 9.8×10-5. Consulting the ALARP principle, the accident risk in an acceptable range.(2)Use ALOHA and bounded continuous Gaussian diffusion model to study the reach of gas leakage accident. Set in 20 MPa, 1 cm aperture,… leakage scenario, the farthest distance is 52 m with the concentration of 6 500ppm(PAC-1), 27 m with the concentration of23 000ppm(PAC-2), 21 m with the concentration of 400 000ppm(PAC-3), 272 m with the concentration of 10% natural gas lower explosive limit(LEL), 108 m with the concentration of 10% LEL. Through contrast analyzing software simulation method and the formula calculation method on the proximal end and far end, it is highly accurate of gas leakage accident risk field simulation with ALOHA.(3)Use CFD software simulate long-narrow confined space gasoline vapor explosion.This article assumes a few petrol leak to sewer, where in junk clogging. After long term volatilization, it is 36.94 ml of liquid gasoline evaporates into gasoline vapor, and mixed with air to form of limit-reached vapor cloud explosion. Due to accidental ignition source, vapor cloud explosion generate about 0.13 bar overpressure and 2 214 k high temperature. And high temperature and overpressure cause petrol container broken and liquid gasoline evaporation rapidly. About 3.694 l gasoline volatile liquid vaporing cloud formation, it forms a larger cloud of steam in low-lying place again. Explosion duration is less than 0.2s, but the blast,especially in the limited state, expand to 35 m diameter and 7.38 bar overpressure extremum.In accordance with the building and the human body overpressure influence scope, the reasonwhy its value is slightly above TNO pluripotent model consequence is that the software model fully considers that the obstruction and limited space has the effect of positive feedback on the overpressure.(4)The article finally propose the "P type flow chart" to guide the strategy of emergency command, from another aspect of emergency disposal —— the perspective of organization and decision making of accident emergency disposal.In this article, through exploring research on the spread of the oil and gas leakage,explosion, such as cloud of steam model, establish the known oil and gas leakage and the influence of other factors, in turn, guide the similar event occurs, how to determine the evacuation crowd evacuation routes and other emergency disposal measures and prevention of oil leakage accident, on the premise of guarantee the people’s life and property safety, reduce accidents as much as possible the impact on the normal social life, reduce to avoid small incidents to expand and the occurrence of secondary disasters, and lay a foundation for afterwards rapid recovery and reconstruction. |
