The influence analysis of process parameters for deep-cooling BOG re-liquefaction of LNG carrier
In recent years,a small deep-cooling BOG re-liquefaction device has been favored by the market and has be-come one of the mainstream configurations of LNG carriers.HYSYS software was used to simulate the cryogenic re-liquefaction process in multiple cases.The minimum power consumption of the system was used as the evaluation index.The influence of the nitrogen and heliumre frigerant proportion and the pressure before and after expansion of the refrigerant on the power consumption was discussed.The results show that the optimal nitrogen helium refrigerant distribution ratio is about 50％:50％when the pres-sure after expansion is less than 9 bar.Increasing the operating pressure of the refrigerant system and the helium content is benefi-cial for reducing system power consumption;when the system pressure is high,the more helium components there is,the lower the power consumption.Compared with existing devices,the energy consumption of the optimized liquefaction devices is less than 800 kWh/t,which providing guidance for the development of re-liquefaction unit.
LNG carrierBOGRe-liquefactionDeep-cooling devicesNitrogen and helium mixd refrigerant
NETL
NSTL
万方数据
