Study On Safety Integrity Level Verification Of Safety Instrument System Based On Petri Net

In recent years,petrochemical enterprises show a trend of large-scale installation,process complexity and high oil vulcanization of raw materials.As a result,the risk of enterprise safety production increased.In order to ensure the continuous production of enterprises and the safety of personnel and property,safety instrument systems like emergency stop system,fire and gas safety systems are designed and applied to the production plant for the purpose of safety protection and suppression of disaster relief.And the SIL evaluation of safety instrument system has become the focus among business managers and security management scholars.In this paper,the judgment basis of safety instrument integrity level is divided into three parts: structural constraints,system capacity and the failure probability of requirements,and the system capacity of the influencing factors and failure mode are analyzed.For the calculation method of system hardware security integrity,Petri net model is introduced by comparing the advantages and disadvantages of reliability block diagram method,fault tree method and Markov model.The validation model of the hardware safety integrity is established because petri net has the characteristics of the visualization and calculateconvenience.The probability of occurrence of the risk failure is reduced by the introduction of some functional tests.The results show that partial functional test can effectively improve the SIL comparing with the calculated results of the original situation.The gasoline hydrogenation unit is choosed as the research object,and the combination of HAZOP and LOPA is used to classify the SIS.The Petri net model is used to verify the safety integrity of the safety instrument system.Improvements and maintenance recommendations for safety instrumentation systems can be put forward to provide a reference for the safety integrity rating of similar devicesaccording to the evaluation results.Finally,a simple security integrity rating software is designed to improve efficiency of the safety integrity evaluation of safety instrumentation systems and ensure the integrity of the process and the accuracy of the results.In recent years,petrochemical enterprises show a trend of large-scale installation,process complexity and high oil vulcanization of raw materials.As a result,the risk of enterprise safety production increased.In order to ensure the continuous production of enterprises and the safety of personnel and property,safety instrument systems like emergency stop system,fire and gas safety systems are designed and applied to the production plant for the purpose of safety protection and suppression of disaster relief.And the SIL evaluation of safety instrument system has become the focus among business managers and security management scholars.In this paper,the judgment basis of safety instrument integrity level is divided into three parts: structural constraints,system capacity and the failure probability of requirements,and the system capacity of the influencing factors and failure mode are analyzed.For the calculation method of system hardware security integrity,Petri net model is introduced by comparing the advantages and disadvantages of reliability block diagram method,fault tree method and Markov model.The validation model of the hardware safety integrity is established because petri net has the characteristics of the visualization and calculate convenience.The probability of occurrence of the risk failure is reduced by the introduction of some functional tests.The results show that partial functional test can effectively improve the SIL comparing with the calculated results of the original situation.The gasoline hydrogenation unit is chosed as the research object,and the combination of HAZOP and LOPA is used to classify the SIS.The Petri net model is used to verify the safety integrity of the safety instrument system.Improvements and maintenance recommendations for safety instrumentation systems can be put forward to provide a reference for the safety integrity rating of similar devices according to the evaluation results.Finally,a simple security integrity rating software is designed to improve efficiency of the safety integrity evaluation of safety instrumentation systems and ensure the integrity of the process and the accuracy of the results.