Vulnerability Study Of Petrochemical Tank Farm Storage Tanks Under Multiple Types Of Accidents Based On Domino Effect

In recent years,the construction layout of petrochemical enterprises has gradually developed in the direction of large-scale and intensive.While this construction method enables enterprises to enhance economic efficiency,there are also safety hazards such as the large amount of equipment in the area and the close proximity.In particular,the storage tank area,most of its storage is flammable and explosive or toxic hazardous substances,once the area fire and explosion accident,the impact is likely to spread to other equipment,and then trigger the domino effect,increasing the severity of the accident.In order to have a more comprehensive understanding of the evolution of accidents in storage tank areas,to better prevent the occurrence of the domino effect,and to reduce the negative impact of accidents,this paper studies the propagation mechanism of the domino effect in accidents in storage tank areas,and analyzes the vulnerability of storage tanks in accidents to identify the units most likely to lead to the expansion of accident hazards,so as to more effectively prevent and control the safety of storage tank areas.At present,scholars have mostly adopted the static Bayesian network(BN)approach for the study of the domino effect mechanism,which is able to identify potential accident units but cannot analyze the process of the domino effect over time.On the other hand,fire and explosion,as the most common types of chemical accidents,often occur one after another in an accident,but many articles also tend to analyze only the occurrence of one accident type,and the analysis results thus obtained may be somewhat different from the actual situation.Taken together,these methodological shortcomings can lead to less accurate results in the analysis of domino effects.In order to more accurately describe the domino effect accidents in the storage tank area,this paper introduces a dynamic Bayesian network model(DBN)based on the use of BN analysis,which is able to dynamically analyze the trend of accidents over time while there is no unidirectional restriction between the nodes of the model.Also,two accident scenarios,fire and explosion,are combined in the study and the synergistic effects between different accident units are considered for impact.The case first determines the climatic conditions of the tank area and the arrangement of the tanks,and then the physical quantities caused by the accident unit to the neighboring units are calculated by ALOHA software and converted into the accident probability of the unit by the Probit formula.Subsequently,Ge NIe software is used to construct BN and DBN models to study the propagation mechanism of domino accidents and analyze the vulnerability of storage tanks under domino accident scenarios.In addition,in order to be able to target the protection of storage tanks,this paper also investigates the effect of safety barrier facilities on the prevention of accident domino effect.Finally,the environmental risk that the leaking chemical will pose is predicted in the case of a storage tank that only leaks and does not evolve into a fire or explosion accident.The results of the study indicate that the wind direction has a significant impact on the hazard of vapor cloud explosion accidents,and that tanks on the downwind side will be more susceptible to the effects of an explosion accident;The probability of a tank accident is higher when the pool fire and vapor cloud explosion accident scenarios are considered together than when only the single-factor accident scenario is considered;The DBN model is able to reflect the trend of tank accident probability over time,which makes its description of the domino effect more accurate compared to BN;The probability of accidents has been significantly reduced in all tanks equipped with different safety barriers.