The Applied Research About Toxic Gas Leakage And Diffusion At Road Transport Accident

With the rapid industrial development, the demand of hazardous chemicals that could be used as raw materials,fuel production or processing materials continue to grow in many industries and related industries.In recent years, transport accidents about hazardous chemicals came one after another, which not only caused significant damage to life,property and the environment,but also brought huge social panic,far beyond the ability of accidents,on our country.To reduce the loss of life and property as well as probability of occurrence,it is necessary to take regulation on dangerous chemicals transport vehicle and make prediction about the harm of hazardous chemicals.Our group jointly set up a dangerous chemicals intelligent transportation system,which includes real-time monitoring of transport vehicles, hazardous chemicals emergency rescue database, decision-making about transport risk and emergency rescue plan after accident.This article focused on the process of leakage and diffusion about toxic gas at road transport, And delineated the potential danger zones according to the relevant injury criteria, to provide technical support for decision-making about risk of transportation and accident emergency rescue plan in the system.After comprehensive comparison of current leakage and diffusion models, this paper selected models that suitable for emergency rescue.For properties of hazardous chemicals and characteristics about transport tankers,This paper considered three common leakage scenarios:the vapor leakage about high(low)pressure liquefied gas、the liquid leakage about high(low) pressure liquefied gas and the liquid leakage about cryogenic liquefied gas,and built their relevant models.At the part of diffusion, this paper explored the difference between heavy and non-heavy gas diffusion,selected the suitable models about instantaneous 、 continuous diffusion, made some improvements on some models. On this basis,It programmed for each model and made some algorithm optimization with MATLAB software, so that it applied to the whole dangerous chemicals intelligent transportation system.Combined with an transport accident about ammonia leakage,the paper made some results after the analysis about the whole process of leakage and diffusion,such as,the scope at the time when concentration reach the farthest downwind distance is not themaximum toxic influence sphere.The final potential risk areas should be achieved throughout the whole dispersion,not only some time.With the help of module form Google earth toolbox,It could be brought the resulting potential hazards region form MATLAB into the actual map on Google earth according to the actual ratio and the corresponding wind direction,which made the result more clear and easier to use.Finally,this paper made simulation about an liquid chlorine truck accident with dangerous chemicals intelligent transportation system,explored the influence to the final result about the surface roughness and the wind speed,and got the final potential hazard area, which provide the theoretical basis and technical guidance for emergency rescue.