洪水诱发储罐失效的定量风险评估方法

Quantitative risk assessment of LOC accidents triggered by floods

为了解决自然灾害诱发的事故灾难(又称Natech事件)的风险评估问题,提出了针对Natech事件进行定量风险评估的流程框架和方法,并应用于洪水诱发储罐失效的概率和后果的风险分析中。该方法首先确定自然灾害的频率和强度,对在此灾害中可能遭受破坏的设备进行风险辨识;然后确定灾害情景的分类和特征,计算洪水触发储罐失效的概率;最后根据事件树分析的方法,对可能发生的灾害情景和后果进行分析。该文假设某化工厂储罐区域因洪水导致储罐失效,进而引发氨气泄漏的案例。应用该方法计算个人风险分布情况,并在地理信息系统(GIS)上进行了可视化展示。研究结果表明:该方法在定量化洪水诱发储罐失效的风险评估中具有可行性;同时给出了相关风险管理的措施和建议。

A risk assessment framework is developed for natural and technological accidents for quantitative risk analysis of loss of containment （LOC） accidents triggered by floods. The method first describes the severity and probability of natural hazards to identify key target equipment. Damage states and reference scenarios are then identificated and the damage probability of a tank LOC is estimated. Finally, the event tree is analyzed to evaluate the consequences of the reference scenario, The overall methodology is applied to a specific case study of a chemical storage tank destroyed by a flood with ammonia release from the tank. The individual risk results are shown on a geographic information system （GIS）. The methodology gives a practical means for risk assessment and helpful suggestions for risk management.