Study On Quantitative Calculation Method Of Dangerous Gas Leakage And Diffusion In Anaerobic Reactor

Anaerobic reactor is one of the most important reaction devices for biogas engineering.Fire,explosion and toxic incidents will be triggered if the biogas leaks,and severe serial explosion accidents will be easily caused if the leakage cannot be identified,monitored and warned early in the process.of production and operation.Research on the leakage and diffusion of the anaerobic reactor is unable to carry on by experiments due to the dangerousness of the anaerobic reactor and the effect of gaseous contamination on the environment.First of all,in order to analyze the state and the diffusion trend of the hazardous gas inside the reactor after leakage,this paper collects the data from the simulation results of biogas leakage and diffusion,fire,explosion and other accidents,analyses the mechanism correlation that causes accidents of such multi-factor coupling as leakage calibers,elevation of leakage source,weather conditions and environments based on accident information,and finds major reasons that cause the anaerobic reactor accidents and their coupling relationships.Second,a multi-parameter coupled model is established in this paper,which can be used to calculate the risk of all kinds of common leakage situations and obtain the information of accident consequences under various scenarios according to parametric variation.What is more,FLUENT software is used to a supplementary verification for the leakage diffusion process of anaerobic reactor,which analysis the velocity field and concentration field distribution after the diffusion of dangerous gas.The change of the flow field after the leakage and diffusion of the reactor is visualized.Finally,this paper develops a quantitative calculation software aiming at the leakage hazards of anaerobic reactor in accordance with this multi-factor coupling empirical model,which aims to leakage risk monitoring.The main contents are as follows:(1)PHAST software was used to calculate the leakage of anaerobic reactor.The simulation of accident consequence are carried out for the height leakage and ground leakage in typical working conditions.A large number of accident data is mined in depth,and the major influence factor of the complicated process,such as leakage calibers,elevation of leakage source.The multi-factor fitting formula of the leakage height,leakage and accident consequences are obtained by regression fitting,which used PHAST to verify the data.(2)FLUENT software was used to a supplementary verification for the leakage diffusion process of anaerobic reactor.Wind field simulation was analyzed by input of main parameters of medium leakage condition,by which the complex effects of wind on air flow are obtained.The phenomenology of anaerobic reactor release and dispersion was investigated based on simulation conditions of steady wind field.(3)The FLUENT simulation results with PHAST and empirical formulas were compared,analyzed various simulation methods the best conditions of use,construction experience coupled multi-factor model,which can predict the consequences of the accident,the reactor leakage accident consequence distance.(4)On the basis of research content,a set of quantitative calculation software has been developed for the leakage hazard of the anaerobic reactor,combined with equipment safety laws and regulations and equipment safety management system,which can calculate the multi-factor coupling accident consequences.And it can give the safety suggestion and load the site map to locate the dangerous radius according to the plan of the plant,so as to achieve the leakage risk monitoring.It can be concluded from application results that this model and method can be applied to other petrochemical devices,so as to monitor the variation of major parameters in the process of production and operation,predict potential accidents and risks,make emergency rescue and evacuation plans for multi-scenario accidents,and provide technical basis for the transportation and storage design for hazardous chemical materials,accident prediction and emergency rescue.