Puguang Gas Station Quantitative Risk Evaluation Technology Research

The gas station is the hub of the entire natural gas pipeline system. Gas station equipments’safe and efficient operation is the most important part to ensure gas supplies. Risk assessment of gas transmission station is not only a way to improve the reliability of the gas system, improve the predictive ability of the accident and hidden parts, but also a way to minimize the accident caused economic losses, casualties and damage to the environment. This article is mainly carried out the following aspects of Puguang gas station based on RBI quantitative risk analysis methods.(1) Pressure vessels and pipes are the object of quantitative risk assessment studies after the field investigation of Puguang gas station. Determine the risk factors of the gas station after the field investigation of Puguang gas station. Establish the fault tree of pressure vessels and piping of the gas stations. Summarizes the main failure mode with site statistical data and come to the following conclusions:Corrosion thinning is the most major failure mode of Puguang gas station. Provide the necessary thinning volume, defect characteristics, and other basic data for quantitative risk assessment by ultrasonic thickness and metal magnetic memory testing for devices.(2) In this article, conduct a study on calculating the failure probability of equipment corrosion thinning failure mode. Compare the following three methods:the mean first order second moment method, the improved first order second moment method and Monte Carlo method. Analyze the advantages of the Monte Carlo method in the calculation accuracy and practical application, to determine the Monte Carlo method. Amend the generic probability of failure of the API581with the correction factor theoretical model. Compared the probability of failure of different diameter pipes, and then concluded that pipeline failure rate with the diameter increase significantly lower. Analyze the influence of operating pressure on the failure probability, and then concluded that equipment failure probability larger with the increase of operating pressure. Failure consequences are calculated using the API581.(3) Establish reliability models of the repairable system in Puguang gas station with the system reliability analysis. Calculate the system failure probability by the reliability element method. Establish risk acceptance criteria of Puguang gas station by research status of risk acceptance criteria and the HSE management requirements of East Gas Transmission stations.(4) Establish a quantitative risk assessment model and use the model to conduct a quantitative risk assessment on Puguang gas station, and obtain the risk of a single device and the whole station. Puguang gas station is now the risk within an acceptable range with reference to the risk acceptance criteria. Develop the test plan of the station equipment, and appropriate risk control measures for different equipment.The conclusions of this paper has great significance to prevent and reduce the economic losses caused by the gas station the accident, saving gas station equipment maintenance, testing and operating costs.