Analysis on liquefied natural gas cryogenic energy composition and discussion on its utilization

Plenty of cryogenic energy is released during liquefied natural gas (LNG) gasification process. The effect on energy-saving and system efficiency is prominent if the cryogenic energy can be recovered for effective utilization. The cold energy of LNG consists of cold exergy and cooling capacity. LNG cold energy recovery methods were divided into cold exergy utilization and cooling capacity recovery. The energy utilization essence of the recovery and utilization of LNG cold energy was also clarified. Power plant and air separation system utilize the LNG cold exergy. Refrigerated storage, air conditioning unit and dry ice production process use the cooling capacity of LNG. Some guiding suggestions were also brought forward for LNG cold energy recovery system. In the power recovery system, high quality energy under low temperature should be utilized reasonably. Decreasing cold loss is very important in the cooling capacity utilization unit.