Study On Safety Assessment Of Loading And Unloading Operation Which Takes Place At Lpg Terminals Based On Fuzzy-FTA Method

As the important part of China’s energy structure,LPG is mainly transported in three ways which are highway,railway and waterway.The maritime transport process of LPG could be divided into export wharf loading,sea transportation and import wharf unloading.Any leakage accident in loading and unloading process will cause huge losses,so it is vital to focus on the safety of the loading and unloading process of LPG ships.Therefore,it is meaningful to analyze the safety of loading and unloading process of LPG terminal theoretically and practically.In this paper,we take the loading and unloading safety of LPG terminals as the research system,and take the first event that we do not hope to happen in the system as the top event,then define the intermediate events and the bottom events scientifically and reasonably according to the literature and several LPG industry standards,finally establish a fault tree where "LPG terminal in an unsafe state" serves as the top event,human factors,terminal factors,management factors and environmental factors serve as the main intermediate events.Because the occurrence probability of the bottom event of this system is not a definite value,the introduction of fuzzy mathematics principle will blur the probability of the occurrence of the bottom event,and we provide the questionnaire to seniors and experts in the industry at the same time to determine the probability level of the occurrence of the bottom events and the accuracy of the probability level of the occurrence of the bottom events,the probability of the occurrence of the top event is calculated through logical AND,logical OR,and triangular fuzzy operators.In addition,this paper analyzes the importance of each bottom event to the top event by the median method,and draws the conclusion.The factors which have a bigger impact on the top event should be given priority.According to the deep research of the thesis and relatively accurate calculation of different events,we can assure the safety of the process.Both the final result and analysis could be used as a suggestion for assuring the safety of LPG terminals.