Study On Fire And Deflagration Characteristics And Three Dimensional Quantitative Risk Analysis Of Oil And Gas Station

Quantitative risk assessment technology,as one of the key technologies of station integrity management,needs to identify the potential hazards of station facilities in the front end loading design and post-operation stage,quantify the probability of accident failure and the seriousness of the consequences,and calculate the corresponding accident risk,assess the risk of acceptability,so that the designer can improve the design program and reduce the failure of the major equipment scientifically and effectively.At present,in the quantitative risk assessment technology,the calculation of the consequences of fire and explosion accident mainly uses some semi-empirical model,the results output is the two-dimensional static output and can not consider the consequences of the accident with the height direction and time changes,as a result,the calculated risk is the two-dimensional static risk and the semi-empirical model also has different defects,which leads to the current quantitative risk assessment technology can not meet the oil and gas station engineering design needs.Therefore,in view of the above problems,this paper uses CFD technology to study the fire and deflagration characteristics of oil and gas station,and combines CFD technology with quantitative risk assessment technology to establish three-dimensional quantitative risk assessment model of oil and gas station,and to improve the existing oil and gas station integrity management technology.In order to establish a three-dimensional quantitative risk assessment model for oil and gas stations,firstly,the numerical model of fire and explosion is validated with the experiment results,the calculated results are in good agreement with the experimental results.Then the numerical prediction model of the gas leakage free jet and block jet diffusion accident,the actual cloud deflagration and flash fire accident,the jet fire and pool fire accident is established and different accidents development is analyzed.For the diffusion law,the natural gas will be blocked in the bottom and vicinity of the barrier and accumulated to form a large area of high concentrations of combustible gas cloud,natural gas concentration field will be shoed in the "bifurcated" shape distribution;For deflagration Law,due to the existence of station process equipment and pipeline,a positive mechanism of flame acceleration and different degrees of deflagration overpressure will be formed;For the fire law,jet fire is blocked and the flame will be extended to the horizontal and be evaluated,the combustion range becomes larger,stable combustion will be expressed as "pool fire" burning regime,the results show that the numerical simulation method based on CFD is suitable for the oil and gas field with dense process pipelines and large and complex equipment.Finally,using the CFD predicting model for the station fire and deflagration accident and combining with the quantitative risk analysis theory to establish three-dimensional quantitative risk assessment model of the oil and gas station,then the three-dimensional quantitative risk assessment software of fire and deflagration is coded,at the same time,the risk of the accident of the pool fire is calculated by software and the risk value is shouwed by the three-dimensional contour map.The risk can be considered with the direction of height and time,and it is more suitable for the oil and gas station Quantitative risk assessment of the field.