HAZOP analysis and optimization of the Safety Instrumented System (SIS) configuration in a potassium nitrate production plant
硝酸钾生产装置HAZOP分析与安全仪表系统（SIS）配置优化研究

摘要

针对硝酸钾复分解法生产高危特性及现有HAZOP分析、SIS系统应用局限，本研究开展相关风险辨识与安全防护优化。通过HAZOP分析明确复分解反应釜温度过高、一效蒸发器压力过高等关键风险偏差及原有安全保护层缺陷。依据IEC61508和IEC61511标准完成关键节点SIL3等级评估，制定传感器冗余选型、逻辑控制器冗余配置等SIS优化方案。现场验证表明，优化后SIS响应时间缩短65.2%，故障诊断准确率提升13.5个百分点，实现重大风险零发生。本研究为硝酸钾生产安全管理及同类工艺提供技术支撑。

Abstract

In light of the high-risk nature inherent in the potassium nitrate decomposition production process and the constraints associated with existing HAZOP analysis and Safety Instrumented System (SIS) applications, this study undertakes comprehensive risk identification and safety protection optimization efforts. By employing HAZOP analysis, critical risk deviations are pinpointed, including elevated temperatures within the decomposition reactor, excessive pressure in the primary evaporator, and deficiencies in the original safety protection layers. In accordance with the IEC 61508 and IEC 61511 standards, a Safety Integrity Level (SIL) 3 assessment is conducted for key nodes. Subsequently, SIS optimization strategies are formulated, encompassing sensor redundancy selection and logic controller redundancy configuration. On-site verification demonstrates that post-optimization, the SIS response time has been reduced by 65.2%, the accuracy of fault diagnosis has been enhanced by 13.5 percentage points, and the occurrence of major risks has been entirely eliminated. This study offers technical support for the safety management of potassium nitrate production processes and analogous industrial applications.