Application Of AERMOD Model In The Hazardous Waste Leakage Emergency Assessment

With the rapid development of chemical industry in China, the increasing hazardous chemicals leakage accidents have caused a large number of personnel and property losses, even bring out serious problems which is unrepairable. And worse still, there are many defects on actual emergency assessment measures for the hazardous chemicals leakage. So in order to provide more effective contingency plans,ensure more secure scope of risk assessment, simulation of leakage and diffusion becomes very important. Liquid ammonia and hydrogen chloride which are included in State Hazardous Waste List” will lead to poisoning and environmental pollution,and they are generally stored in tanks. When leakage accidents occur, ammonia and hydrogen chloride will diffuse into atmosphere by the dominant role of atmospheric turbulence.Through introducing the theory of leakage sources and the gas diffusion models,this paper chose the AERMOD diffusion model which is based on Gaussian plume model and basic theory on the boundary layer meteorology, and expatiated its operating system and selection of the main parameters.The paper chose one of hazardous waste disposal companies in Ma’anshan,Anhui Province as the research subject. Firstly, meteorological data and topographic data in Ma’anshan were collected, assumed that liquid ammonia and hydrogen chloride leaked from the tanks with continuous small holes, aperture was set to 2cm、3cm and 4cm separately. Then it used the AERMOD diffusion model to simulate the scope of diffusion quantitatively, calculated the diffusion concentration of pollutants,and drew the concentration contour map by using Surfer8. At last, the special contingency plans for ammonia and hydrogen chloride were proposed and assessed according to emergency assessment and the simulated results.The simulated results have a certain degree of guiding significance on emergency scope assessment. It has a definite pertinence on assessing special contingency plans.It can also provide assistance for crowd evacuation in emergency command.