Research On Risk Evaluation Technology Of Underground Facilities Of Gas Storage

The underground natural gas storage is a key facility for peak shaving and ensuring the safe transportation of natural gas.It is an artificial gas field or gas reservoir formed by re-injecting the extracted natural gas into the underground storage space for storage.It plays a vital role in the production and transportation of natural gas,and not only the peak shaving tools but also the important role of emergency.Once the gas storage leaks,it will cause a huge disaster.This article will focus on the depleted oil and gas reservoir-type underground gas storage as an example,analyze the failure probability and failure consequences of the underground facilities of the gas storage,and quantitatively evaluate the risk degree of its underground facilities.Divide the underground facilities of the gas storage into four major units,identify the risk factors,construct the failure fault tree of each unit,and determine the basic failure events.Using fuzzy numbers to eliminate the subjectivity of expert scoring method,combined with failure database to determine the failure probability of basic events.The failure tree of each unit is mapped to a Bayesian network,and Bayesian network reasoning is used to calculate the failure probability of each unit and the system failure probability.Combine sensitivity analysis and influence analysis to identify key risk factors.Introduce the time factor,construct a dynamic Bayesian network,and analyze and evaluate the system dynamically.The failure type of the underground facilities of the gas storage is mainly leakage,which will lead to disasters such as jet fire,steam cloud explosion,and diffusion,and ultimately reduce the injection and production capacity.To quantify the possible consequences of failures,and the impact on human life safety,economy and environment.Among them,the life safety of people mainly considers the number of deaths and safety of people after disasters;the economic aspect considers the cost of loss of product injection and production capacity,facility maintenance costs,and property losses caused by disasters.Take Wen 96 gas storage as an example,conduct risk assessment,and propose risk reduction measures based on the evaluation results.