Research On Risk Assessment Model Of Large Oil Storage Tank Area Based On ARAMIS System

Although the large-scale and intensified storage tank area has met the needs of national economic development and strategic reserves,it also brought a series of new challenges to the safe operation of storage tanks.Assessing the safety status of large oil storage tanks is of great significance to improving the level of risk control measures,reducing the occurrence of major casualty accidents and ensuring the safe operation of storage tanks.Taking the storage tank area as the research object,this paper establishes a risk assessment model for large-scale oil storage tank farm based on the risk assessment methods for industrial accidents.The main work contents are as follows:（1）A risk assessment model for large oil storage tanks based on risk assessment methods for industrial accidents was established to comprehensively analyze and evaluate the possibility of accidents occurring in tank farms,the severity of accident consequences,and the vulnerability of tank system.The risk level of the tank area was determined.（2）The key events are identified and analyzed in detail,the risk factors that lead to the key events are identified from the process,operation,design and environmental changes,and the key events are taken as top events to determine the probability of the occurrence of the event through establishing the corresponding accident tree maps.（3）The risk mitigation measures adopted by the evaluation objects are identified,and the performance of risk mitigation measures is evaluated,so that the risk level of the storage tank area is closer to the real situation.Risk mitigation measures include both technical and management types.According to the reference value provided by the International Electrotechnical Commission standard,the average failure probability of technology risk mitigation measures is determined.Based on the characteristics of the storage tank area and safety management,an index system for risk management mitigation measures for large oil storage tank areas was constructed.Questionnaire survey forms were used to analyze to determine correction factors for management risk mitigation measures.（4）An event tree is set up to analyze and determine the possible hazards caused by the key events,the probability and consequences of dangerous phenomena.The risk matrix diagram is used to select the reference accident scene which the key events may lead to,and the mathematical model is used to calculate the risk consequences of the storage tank.（5）Using proportional relation,the system vulnerability of storage tank area is quantified.By analyzing the vulnerability of the people,environment and facilities in the tank area,the quantitative factor is determined.The vulnerability index of the tank area is determined according to the proportions of the vulnerability of human,environment and facilities.（6）A storage tank area is selected as the research object,and the risk assessment is carried out.The probability of the rupture of the tank liquid container is 6.72?10^-4,the risk consequence index of the storage tank area is 1.68?10^-4,the overall vulnerability index of the storage tank area system is 0.159,and the overall risk of the storage area value is 2.7?10^-5,it is a tolerable risk.The conclusion shows that the evaluation results accord with actual,verify the validity and feasibility of the model.