Risk analysis of hydrogen leakage in liquid hydrogen tankers
The risk of hydrogen leakage during the operation of liquid hydrogen tankers was analyzed and assessed by using the principles of risk management system engineering and the fault tree analysis method.The mechanisms behind the hydrogen leakage accidents in the liquid hydrogen tankers were analyzed,outlining 32 basic events and 17 intermediate events,establishing a fault tree model.Based on the structural analysis of fault trees,the minimum cut set was solved to determine the structural importance of each basic event.A fuzzy method based on expert experience judgment was used to predict the probability of basic events.The minimum cut set calculation method was used to approximate the probability of hydrogen leakage top event,and the importance of event probability was calculated.Semi-quantitative analysis of fault trees was achieved,and a hydrogen leakage risk assessment system for liquid hydrogen tankers based on fault trees was constructed.Based on the structural importance and probability calculations of events,6 significant risks were identified:external force damage to the tank body,external heat damage to the tank body,jamming of the shut-off valves,safety valves failure,external force damage to the shut-off valves,and pressure relief failure.Targeted preventive measures were proposed,including daily routine inspection,installation of tanker protective devices,and monitoring of liquid hydrogen tank failure,to reduce the risk of hydrogen leakage in liquid hydrogen tankers.
liquid hydrogen tankerhydrogen leakagerisk assessmentfault tree analysispreventive measures