Different level of cold energy is needed in the cryogenic separation process of an ethylene plant

so the ethylene separation process can be treated as a cold sink. Heat is needed in a LNG gasification process which can be treated as a cold source. This work combines the ethylene cryogenic separation process with the LNG gasification process

so that the cold utility demand in the ethylene cryogenic separation and the heat utility demand in the LNG gasification process are both reduced. The light hydrocarbons which get from LNG separation process can be a perfect cracking feed for the ethylene plant. A plant with a 3000000 t·a-1 LNG process and a 640000 t·a-1 ethylene process is used as a case study. The simulation results show that LNG plant can provide 41464 kW cold utility for the ethylene plant

reducing 75% refrigerant consumption of the ethylene plant. It also provides 650000 t·a-1 high quality cracking feed for the ethylene plant.