Research on BOG compression and re-liquefaction of LNG cargo at LNG filling station

In recent years, with the rapid development of LNG filling station, the amount of boil-off gas(BOG) is very large because of the relatively slow development of LNG vehicles.Especially after LNG unloading for the LNG tanker, the pressure of BOG is 0.2 to 0.4 MPa.The BOG process related to energy consumption and safe operation is one of the critical issues that should be considered at LNG filling station.A set of BOG compression and re-liquefaction process and equipment is established by using the LNG cold energy to recover BOG to avoid energy dissipation and environmental pollution caused by BOG direct discharge.A BOG recovery experimental setup is built and some experiments are carried out with liquid nitrogen and LNG.The results show that the ratio of BOG recovery is 90% when the ratio of BOG and LNG is 3%.Accordingly, the process of BOG compression and re-liquefaction is an effective way for BOG recovery.