Simulation And Prediction Research On Emergency Evacuation Of Liquid Ammonia Station Leakage And Diffusion Accident Of A Chemical Company In Yunnan Province

Liquid ammonia is one of the important chemical raw materials,and has been widely used in agriculture,medicine and national defense industry.Liquid ammonia is stored in liquid ammonia storage tanks in most chemical enterprises,and leakage accidents occur frequently in storage tanks which are used for a long time.Once the production leakage accident occurs,it will cause casualties and property losses,and even cause serious social panic.The leakage of liquid ammonia may cause acute poisoning or death of the surrounding personnel,and may even cause fires and explosions.Therefore,it is important to study the leakage and diffusion mechanism of liquid ammonia tank,simulate the accident consequences,and simulate the emergency evacuation after the leakage and diffusion accident,which is of great significance to the prevention of accidents and the emergency rescue after the accident.In this paper,through a large number of literature,combined with the actual situation of Yunnan Xiang Feng Jin Mai Chemical Co.,Ltd.,the leakage of liquid ammonia as an example,the main work is as follows:(1)by collecting data,the leakage of liquid ammonia is calculated by using Bernoulli equation,and four factors affecting the leakage and diffusion of liquid ammonia are summarized,and the concrete explanation is made.The Gauss diffusion model was established for the liquid ammonia tank in the liquid ammonia station.According to the continuous leakage and instantaneous leakage of liquid ammonia,two models of Gauss smoke and Gauss smoke were used to calculate the spatial distribution of liquid ammonia concentration.(2)according to the study object set under six kinds of atmospheric stability conditions,the variation of leakage diffusion concentration of liquid ammonia tank with the lower wind distance is obtained by MATLAB numerical simulation.In the continuous leakage,with the increase of the atmospheric stability,the distance of the point distance from the point of the leakage diffusion concentration is 56 m To 851 m,the maximum of the concentration is also reduced from 227.8g/m3 to 83g/m3,and thedistance between the lethal area,the serious injury area and the injured area is gradually increased under each stability,and the distance of the point distance from the leak source point is increased to 611 m in the instantaneous leakage,and the maximum of the concentration is also reduced by 2295g/m3.For 217.9g/m3,the distance between the lethal area,the seriously injured area and the injured area gradually increased under various stability levels.(3)Building-Exodus simulation system is applied to simulate the evacuation in the factory area.The influence of building safety exit quantity,width and obstacles on evacuation in buildings is simulated and analyzed.Through the simulation,the number and width of the safety exit have the most obvious influence on the results of the evacuation simulation,so the improvement of the width and quantity of the export is mainly taken into consideration when providing security advice.Finally,according to the above simulation,suggestions are put forward to provide the reliability suggestions for the evacuation of the factory personnel during the accident,so that the rescue work of the hazardous chemical leakage accidents will be carried out more smoothly,and to avoid more people's property loss and environmental pollution.