LOPA分析方法在中俄东线压气站的应用与思考
Application of LOPA analysis method in compressor stations of China-Russia Eastern Gas Pipeline and consideration
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摘要: 为深入推进油气管道的区域化管理模式, 评估典型压气站场现有保护措施是否足够, 提高典型站场的风险管控能力, 在全面开展危险与可操作性分析(HAZOP)的基础上, 进一步采用保护层分析方法(LOPA), 通过计算残余风险发生的频率, 对站场安全仪表系统(SIS)功能回路的安全完整性等级(SIL)进行评估。以中俄东线某压气站压缩机入口流量低风险点为例开展LOPA分析, 结果表明: 该风险点在不考虑压缩机组本体保护的前提下, 仅环境影响能够满足风险可容许标准, 人员伤亡、经济损失、声誉影响均不满足风险可接受标准, “压缩机轴振动、轴位移等高高联锁自停保护”需满足SIL2等级要求, 降险能力不能低于464。开展LOPA分析可有效解决HAZOP分析中残余风险不能定量化的不足, 评估现有保护层能否使风险降低至风险可容忍标准, 以期为相关天然气压气站开展SIL定级提供经验借鉴, 同时对目前油气管道行业在LOPA分析、SIL定级过程中存在的不足给出管理建议。Abstract: In order to further promote the regional management mode of oil and gas pipelines, evaluate the adequacy of existing protection measures for the typical stations and enhance the risk control capability thereof, the safety integrity level(SIL) of the functional loops of the station safety instrumentation system(SIS) was evaluated, by calculating the occurrence frequency of residual risks with the layers of protection analysis(LOPA) method, based on the comprehensive hazard and operability analysis(HAZOP). LOPA analysis was performed on the low-risk point of compressor inlet flow of one compressor station in China-Russia Eastern Gas Pipeline. The results show that: only the environment impact of the risk point without considering the protection of compressor body can meet the risk tolerance criteria, but personnel casualties, economic loss and reputation effect do not meet the risk tolerance criteria. The auto-stop protection of highhigh interlock for shaft vibration, displacement and others of compressors should satisfy the requirements of SIL2, and the risk reduction capability should not be less than 464. Generally, LOPA analysis can effectively solve the deficiency that the residual risk cannot be quantified in HAZOP analysis, and evaluate whether the existing layer of protection can reduce the risk to the tolerance standard, so as to provide experience reference for SIL rating of relevant natural gas compressor stations. At the same time, some management suggestions were put forward for the shortcomings of LOPA analysis and SIL rating in oil and gas pipeline industry.