一种基于HAZOP-LOPA的碱回收燃烧工段安全仪表系统设计方法

A HAZOP-LOPA-based Design Method for Safety Instrumented Systems in the Recovery Combustion Section of Alkali Recycling Processes

关键词:  碱回收燃烧工段  HAZOP-LOPA  安全完整性等级  安全仪表系统  风险量化

Key Words:alkali recovery combustion section  HAZOP-LOPA  safety integrity level  safety instrument system  risk quantification

摘要:针对当前造纸工业安全仪表系统（SIS）设计方法存在的风险分析碎片化、定量评估不足等问题，本研究以碱回收燃烧工段汽包控制部分SIS设计为例，提出一种基于危险与可操作性分析-保护层分析（HAZOP-LOPA）的SIS定级及设计方法。首先对碱回收燃烧工段进行工艺流程节点划分，并设计对应的风险概率-后果二维风险矩阵，通过HAZOP方法系统识别该工段的潜在偏差与风险场景，结合LOPA分析构建独立保护层量化模型；然后基于风险传导特性建立保护层分析-安全完整性等级（LOPA-SIL）动态映射关系，对SIS等级进行合理定级，最后根据定级结果进行SIS的设计，并通过系统失效概率、剩余风险值等指标验证系统的有效性。结果表明，该方法可成功识别2项高风险场景并判定需增设SIL2级SIS，改进后将风险概率成功降至企业可接受水平（<1.0×10^-6/年）。

Abstract:In response to the problems of fragmented risk analysis and insufficient quantitative evaluation in the current design methods of safety instrumented systems (SIS) in the paper industry, this paper took the SIS design of the steam drum control part in the alkali recovery combustion section as an example and proposed a SIS grading and design method based on hazard and operability analysis-layer of protection analysis (HAZOP-LOPA). Firstly, the process noded of the alkali recovery combustion section were divided, and a corresponding two-dimensional risk matrix of risk probability consequence was designed. The potential deviations and risk scenarios of this section were systematically identified through the HAZOP method, and an independent protection layer quantification model was constructed by combining LOPA. Then, based on the risk transmission characteristics, a layer of protection analysis-safety integrity level (LOPA-SIL) dynamic mapping relationship was established to reasonably classify the level of the SIL. Finally, the SIL was designed according to the classification results, and the effectiveness of the system was verified through indicators such as system failure probability and residual risk value. The results showed that this method could successfully identify two high-risk scenarios and determine the need to add SIS of SIL2. After improvement, the risk probability was successfully reduced to an acceptable level for the enterprise (<1.0×10^-6/year).