重大危险源定量风险评估实例解析

Exemplary analysis on the quantitative risk assessment of major hazardous installations

为贯彻执行《危险化学品重大危险源监督管理暂行规定》,控制危险化学品和重大危险源周边重要目标和敏感场承受的风险,系统研究了危险化学品重大危险源辨识、分级和定量风险评估应用技术,包括设备单元选择、失效模式和失效频率确定、风险计算和评估等关键技术。应用建立的定量风险评估技术方案,对某小型石油化工厂的危险化学品生产装置、储存设施进行了重大危险源辨识、分级,用Phast Risk软件对一级危险化学品重大危险源进行了定量风险计算,并进行风险评估,提出了降低风险的解决方案。

This paper intends to provide better quantitative risk as- sessment technical means for identifying and classifying major hazard installations v/a an exemplary analysis of a small petrochemical plant. For the said research purpose, we would like to quote the Interim Provisions of Supervision and Management of the Dangerous Chemi- cals and Major Hazard Installations （Decrde No. 40 issued by the State Administrative Bureau for Safety Affairs）. According to the de- mands of the corresponding departments of the state, dangerous chemicals and main hazardous installations should be well identified and classified so as for them under the particular state of proper con- trol and management. It is for this strong need that we have proposed a technical scheme of quantitative risk assessment of such chemicals and installations. It is also demanded for the operators and attendants of such chemicals and installations to learn to know clearly where to install such equipment and how to make sure the proper space and distance to put them and properly protect with proper screening and shade from environmental pollution, particularly when they are put outside in the open space. And, next, we have made a detailed dis- cussion on how to check the sources and data that may lead to the damage of such chemicals and installations. In doing so, we have provided different risk categories and likely social risk F - N curve as a kind of likely risk indexes to inspect and determine the objective major hazard sources by taking such dangerous chemicals and hazard installations in a small petrochemical plant as a case sample. The re- suits of our practical application of our research results show that the quantitative risk assessment should be done for raw material storage area as the first step and then have a comprehensive program on time- ly checking and do regularly qualitative evaluation of such chemicals and installations. And, for this purpese, it is recommended to use a software of Phast Risk and the Societal Risk . The results indicate the evaluation of separate individual risks are to be done over the sensi- tive sites and even parts of residential areas of the plant outside, such risks and hazards may exceed the tolerable value 3 x 10-7 and 1 x 10-6, or the social risk tolerable value. Therefore, the above said small petrochemical plant should be entirely moved to other places. Thus, the technical scheme can obviously provide a useful reference to quantitative risk assessment of such dangerous chemicals and haz- ard installations.