The differences in risk assessment between HAZOP and LOPA methods: Loss prevention for the hydrogen compressor operated in a petrochemical plant

• Main Authors: Chen, Kun-Hsien, 陳昆賢
• Other Authors: Shu, Chi-Min
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/tbg732

碩士 === 國立雲林科技大學 === 環境與安全衛生工程系 === 106 === In the present society, the petrochemical industry occupies an important position. However, once a disaster occurs in a petrochemical plant, apart from causing equipment damage and casualties, serious cases will further affect the ecology and residents in the surrounding areas, Therefore, it is a very important link in the prevention and control of a factory. Through various risk assessment tools to evaluate the potential hazards in the operation of the plant, we can understand the probability and severity of the risks and propose corresponding improvements. And Prevention and control, reduce the degree of disaster. HAZOP is currently a high–impact assessment tool, is a major risk assessment method for major corporations. By using the HAZOP evaluation tool, the nodes in the assessment tool are deviated from the guide word, parameters, deviation matrix analysis, risk assessment matrix, Sex, seriousness to get the risk level, but the risk assessment results only risk level, can not effectively quantify the danger. Another analytical tool, the LOPA–Protection Layer Analysis, is based on the IEC61511–3 LOPA Form to get the maximum allowable semi–quantitative risk and the risk to be neglected. LOPA assessment direction can be more detailed risk–time ratio, the rate of personnel exposure, the probability of ignition frequency correction coefficient calculation, through the independent protective layer and the incidence of intermediate events were reduced risk, which in turn safety instrumented functional integrity level (SIL) for the most important basis. In this study, hydrogen compressor was chosen for risk assessment, mainly due to hydrogen compressor accidents in many petrochemical plants in recent years. Most of the factories only conducted import–export HAZOP evaluations on compressors. The study, by combining HAZOP with LOPA, explains why a hydrogen compressor accident can occur in a petrochemical plant that has already undergone risk assessment, and then discusses the pros and cons of HAZOP and LOPA.