Abstract:

In order to solve the problem of quantitative risk assessment of vapor cloud explosion accident under the condition of urban gas pipe network leakage, a grid risk assessment method was proposed. Firstly, the influence factors of pipeline failure and the loss type of vapor cloud explosion caused by pipeline leakage were analyzed comprehensively, and the risk value of the center point of the grid was obtained by multiplying the failure probability of the pipeline and the monetary quantified value of the consequence loss in the grid after the vapor cloud explosion caused by leakage at a certain point of the pipeline. Then, based on the principle of superposition field, the risk value of each point in the pipeline segment that had an impact on the center point of the grid was coupled and superimposed to obtain the total risk value of each center point of the grid, and then the risk contour line of the evaluation area was drawn. Finally, the method was applied to a field to draw the risk contour line of vapor cloud explosion of gas pipe network leakage in a certain area. According to the risk acceptability criterion, the evaluation area was divided into special, key and general protection areas, and the corresponding protection area scope was obtained. The results show that the method can accurately evaluate the risk of vapor cloud explosion accident of urban gas pipe network leakage, and make regional risk division more refined and visual than traditional methods, which is helpful to improve the utilization rate of social security protection materials.

Key words: gas pipeline network, vapor cloud explosion, risk assessment, monetary quantification, superposition field