【作者】 孟令慧；

【导师】 吴重光；

【作者基本信息】 北京化工大学 ， 系统工程， 2008， 硕士

【摘要】 石化过程工业涉及复杂的系统流程,具有变量多,危险点多的特征。对系统进行风险分析,需依照标准流程,遵照国际标准进行。采用SDG-HAZOP进行复杂系统危险推理,可以分析辨识出系统蕴含的危险后果、原因和传播通路。对分析结果进行防护层分析,可以确定系统是否达到安全要求。当未达到允许的安全标准时,所需风险的降低即所需的安全仪表系统完整性等级(SIL)可以确定。为防护层设计提供必要的依据和指导,可以更好的降低系统风险并提高安全性。最终确定危险后果的风险,并得出所需安全仪表系统的完整性等级,是我们所要实现的目标。如何从SDG-HAZOP所得到的结果中分析出主要危险源、主要危险后果以及风险度,定量后果风险计算在具体执行中都面临同样的一些问题:如现阶段在进行后果的定量风险计算主要依靠专家人工评价,对评价人员要求较高,缺乏自动化方式,并且效率较低。本文根据国际标准IEC-61508的指导意见,通过几种常用方法的比较,确定了利用系统模型的定量风险来确定所需安全仪表系统完整性等级。考虑到过程工业系统的特点,选择了在现有SDG-HAZOP系统危险传播通路分析推理的基础上,建立了利用计算机对事故概率以及风险数值进行计算的方法,并以此作为安全仪表系统完整性等级制定的工具。初步建立了SDG概率计算规则库,设计了SDG通路概率计算方法和树状SDG分析方法,以及相应的计算机程序实现。为便于SDG通路的存储、查询与提取,设计了相应的数据库架构。本软件模块与SDG-HAZOP软件完整结合,成为整个安全分析平台一部分。讨论了基于SDG-HAZOP的安全仪表系统完整性等级制定的流程、系统基本构成和各个功能模块的设计与实现。本文最后对现有SIL等级制定方法优缺点进行了阐述,提出了今后发展的方向。更多还原

【Abstract】 Petrol-chemical industry has complicated process, many parameters and dangerous points. Analyzing risk of process system need follow standard procedure and international standard. By SDG-HAZOP risk inference, we can identify accident consequences, dangerous reasons and paths. By layer of protection analysis (LOPA), we can decide whether the system safe or not. If it doesn’t satisfy demand of standard, risk reduction, which is safety integrity level (SIL), will be assigned. It can direct layer of protection design and provide data to support its design. Getting accident consequence risk and SIL is aim of mine.How to get main dangerous source, accident consequence, risk level from data by SDG-HAZOP, and quantitative risk calculation in execution face the same problem: in present period, consequence quantitative risk calculation mainly depends on experts asserts, need high quality of them, lack of automation method and in low efficiency.On the basis of IEC-61508 directive suggestion, this thesis compares several general methods and comes into a result: assignment of SIL by system model’s risk. In consideration of process industrial characteristics, the thesis presents a method of computing accidental probability and risk value by computer on the basis of SDG-HAZOP systematic dangerous paths analysis and inference. It also can be a tool of assigning SIL. Preliminarily constructs a rule library of SDG probability calculation, designs methods of SDG paths probability calculating and SDG tree analysis. Related program is designed. In order to store, search and abstract data from SDG paths, related database architecture has been established. This software module can work closely with SDG-HAZOP software and become a part of Safety Analyze Platform. Make a discussion on designing and realizing process, basic structures and components of SIL assignment, which is based on SDG-HAZOP. Finally, this thesis elaborates advantage and disadvantage of method and technology used now. Put forward some advice on future development of assignment on SIL.更多还原