海上调整弃置井井筒泄漏分析与安全管理

WELLBORE LEAKAGE ANALYSIS AND SAFETY MANAGEMENT OF OFFSHORE ABANDONMENT OF ADJUSTMENT WELLS

近年来,海上调整弃置井不断增加,而目前对井筒泄漏缺乏合适的安全评价方法和管理措施。油田的安全生产面临着严重的安全隐患。针对这一问题,从井筒完整性角度出发,绘制调整井弃置后井屏障图,对井筒泄漏原因进行了分析,得到油气的井下泄漏途径,并以此推导出油气泄漏条件和关键井屏障单元。结合FTA-LEM安全评价方法,以海上调整弃置井发生井筒泄漏作为顶上事件,建立调整弃置井井筒泄漏事故树,并通过临界重要度计算、优化,得到各基本事件的危险源分级结果,最后通过博德事故因果连锁理论,将危险源分级管控,结合人、机、料、法和环境的质量管理理论,提出了海上油田降低海上调整弃置井井筒泄漏概率的安全管理措施。该分析过程可为相关安全管理工作提供借鉴。

In recent years,the number of offshore abandonment of adjustment wells has been increasing,and the current lack of appropriate safety evaluation methods and management measures for wellbore leakage have exposed oilfield safety production to serious potential safety hazards.Aiming at this problem,the well barrier diagram after abandonment of adjustment wells is drawn from the perspective of wellbore integrity;the causes of wellbore leakage are analyzed;the leakage path under oil and gas wells is obtained,and the oil and gas leakage conditions and key well barrier units are deduced.Combining with FTA-LEM safety evaluation method and taking the wellbore leakage of offshore abandonment of adjustment wells as event to be analyzed,the wellbore leakage accident tree of abandonment of adjustment wells is established,and the hazard classification results of each basic event are obtained through critical importance calculation and optimization.Finally,through Bode accident causal chain theory and combining the hierarchical control of hazard sources with the quality management theory of human,machine,material,method and environment,this paper puts forward the safety management measures to reduce the leakage probability of abandonment of adjustment wells in offshore oil fields.This analytic process can provide reference for relevant safety management work.