Abstract: LNG marine BOG liquefaction unit has been monopolized by foreign countries for a long time. Through the study on cryogenic reliquefaction system,the cryogenic process scheme is established,and the research and analysis of engineering machinery,fluid mechanics,heat transfer and other related theories are applied to establish the system component model and the overall analysis model,complete the system static parameter simulation,and then obtain the working point parameters of each component through the refrigerant combination optimization and the process parameter optimization,and finally form a 0.5 t/h cryogenic device process package.

Key words: LNG, BOG, reliquefaction, cryogenic device