Research On The Safety Integrity Level Evaluation Of Safety Instrumented System

The rapid development of economics and society has significantly improved the scale and complexity of petrochemical plant, and people have increasing demand for environment and security. As an important guarantee for the safety of petrochemical plant, there are still some problems on the specific, reasonable and effective of the safety instrumented system. Therefore, it is very important to carry out the safety integrity level assessment, which means a lot for reducing the frequency of accidents, protecting the personal safety and the full and stable operation of devices. The main work in this paper is summarized as follows:Firstly, this paper examines the safety integrity level assessment methods and procedures with the actual situation, obtains the assessment system which using hazard and operability analysis for the recognition of safety instrumented function, using protective layer analysis method for the level assignation and using fault tree analysis for the verification calculations.Secondly, based on fault tree analysis, different redundancy structures and the reliability model under different test cycle of the same redundancy then the calculation results are analyzed and summarized.Finally, the paper takes the coal pressurized gasification plant as example, gives a comprehensive exposition of the techniques and application of the safety instrumented system safety integrity level assessment. The result shows that this method has good practicability.