综合人因可靠性的输气站场安全仪表系统分析与优化

Analysis and Optimization of Safety Instrument System of Gas Transmission Station Based on Comprehensive Human Reliability

为提高输气站场的本质安全,针对有人因影响的安全仪表回路,将人为应急响应与原SIF回路构成一个串联系统,提出在观察阶段、判断阶段和决策阶段分别采用CREAM、HCR和THERP的人因可靠性模型求解失效概率,构建与人因可靠性相关SIL评估模型,并针对某输气站场分液罐的安全仪表系统进行SIL定级与优化。结果表明,人因部分的失效概率占比与执行机构的占比接近,说明人因可靠性可直接影响SIF回路的正常运行;改变冗余结构为1oo2型,测试周期变为0.5 a,可满足SIL验证的要求;可从岗位技能培训、应急安全演练、改善工作场所软硬件条件等方面降低SIS风险,确保SIS功能的安全可靠。

In order to improve the intrinsic safety of gas transmission stations,for safety instrument circuits affected by human factors,the human emergency response and the original SIF circuit are combined to form a series system.In the observation stage,the judgment stage,and the decision stage,human reliability models of CREAM,HCR,and THERP are used respectively to solve the failure probability,and the SIL verification model of comprehensive human reliability is constructed.SIL grading and optimization are carried out for the safety instrument system of the separation tank in a certain gas transmission station.The results show that the proportion of human factor failure probability is close to that of the actuator,indicating that the reliability of human factors can directly affect the normal operation of the SIF loop.The redundancy structure is changed to 1oo2 type,and the test cycle is changed to 0.5 a,which can meet the requirements of SIL verification.SIS risks can be reduced from the aspects of job skills training,emergency safety drills,improvement of software and hardware conditions in the workplace,etc.,to ensure the safety and reliability of SIS functions.