稠油集输管道泄漏事故安全评估分析

Safety assessment and analysis of the leakage accidents in heavy oil gathering and transportation pipeline

为降低稠油集输管道泄漏事故风险,预防重大泄漏事故的发生,基于稠油集输管道泄漏事故的贝叶斯网络,先利用信息扩散理论分析小样本数据,通过引入用来表征在一定期望值上的泄漏失效概率参数--泄漏指数,得到泄漏事故发生的失效概率和超越概率;后又利用模糊集合理论确定泄漏后果的严重程度。利用上述方法对我国西北某油田稠油集输管道进行泄漏事故安全评估,结果表明,利用该方法能够在数据缺失条件下得到较为精确的泄漏概率和泄漏后果概率,适用于稠油集输管道泄漏安全评估。

The aim of the said paper is to introduce a parameter known as the leakage index featured in providing for a certain means to prevent from the leakage failure liability to a certain expected extent based on the Bayesian network.For the said purpose,it is first of all necessary to establish a Bayesian network through comprehensive analysis of the likely leakage-involving factors from the following 4 aspects,that is,the 3-rd party failure,the corrosion of the pipeline,the improper operation of the pipeline running procedures,the mis-attachment of the material/the improper welding of the pipeline or its mislinkage.Thus,for the above mentioned purpose,it would be necessary to analyze some sampling data favorable for converting the single-valued samples into a set of valid ones by taking the advantages of the information diffusion theory.And then,it is also of real need to calculate the failure probability and transcendence probability of the leakage accident more precisely.And,next,we have alsocalculated and assessed the severity of the leakage consequence in accordance with the fuzzy set theory.That is to say,it is not easy to quantify directly the severity indexes of the consequence and convert them into triangular fuzzy values merely on the basis of the expert judgment.Rather,it is necessary to gain the quantitative value of the severity of the consequences by defuzzification.The above mentioned means and methods should thus be adopted to verify the heavy oil gathering pipeline to a certain oil field in the northwest of the country.The results of the above investigation and examination indicate that corrosion turns to be the chief cause likely to lead to the leakage of such pipeline,whose transcendence probability of unacceptable degree may account for72.1%.Therefore,effective measures should be taken to slowdown the corrosion rate.Besides,the misoperation personal injury likely to cause can also be terribly serious.Therefore,great and much more closer attention should be paid to the regular training of the operational employees and managerial members.Apart from this,urgent suggestion has to be put forward to implement the operating procedures strictly.And,all the above mentioned measures and suggestions can all help to lay a certain theoretical foundation for the pipeline safety managers to take appropriate measures to reduce or get rid of the leakage risk liabilities to guarantee the smooth and safety production on the condition of insufficient data.