蒙特卡洛分析在氯气泄漏事故环境风险评价中的应用研究

Application of Monte Carlo analysis in environmental risk assessment of a chlorine release accident

气体泄漏事故环境风险系统中存在的不确定性问题影响了定量环境风险评价结果的科学性和实用性.因此,本研究采用蒙特卡洛分析方法对氯气泄漏事故风险系统中的6个风险变量进行分析,并进一步对气体泄漏过程进行仿真模拟,得到模拟结果及其概率分布.同时,将蒙特卡洛分析结果、毒性剂量反应指标和风险受体信息在地理信息系统中进行综合分析,以个人风险和社会风险表征风险受体暴露在特定风险场内的风险大小,并作为判定风险是否能够被接受的依据.最后,以南京化工园内某氯气储罐泄漏事故为例进行研究.结果表明,氯气泄漏事故的总体社会风险值偏高,超过社会风险的可接受阈值,需要采取适当的风险管理措施来降低相应的风险水平.本研究提出的基于蒙特卡洛性分析的环境风险评价方法克服了传统风险评价结果片面的缺点,能够全面地反映突发环境事故的风险,为环境风险管理决策提供更加科学可靠的信息支撑.

The epistemic uncertainties are important factors that reduce the reliability of quantitative risk assessment （QRA） of chlorine release accident.Monte Carlo analysis is used to assess the effects of six epistemic uncertainty sources on the result of vapor release modeling,and the result of uncertainty analysis is integrated into the final result of QRA.In geographic information system （GIS）,the result of QRA are characterized in terms of individual risk and societal risk,and based on which the tolerability of risk is evaluated.A case study of application of the improved method of QRA on a chlorine release accident was carried out.It showed that the societal risk of the accident was not tolerable;some recommendations on environmental risk management were proposed for risk mitigation.It is concluded that the integration of Monte Carlo analysis with QRA is a more complete,scientific and reliable measure of risk assessment.