A Novel Air Liquefaction Process by Using LNG Cold Energy

Abstract

Since imported LNG is increasing gradually in China, the research of LNG cold energy utilization becomes quite urgent. A novel air liquefaction process with LNG cold energy utilization is proposed in this paper. With the Aspen plus software, this paper builds the simulation model of the air liquefaction process by using LNG cold exergy and analyzes the effects of the key parameters on the performance of the process. The results show that the power requirement to produce liquid air with LNG cold energy utilization is 142.9kWh/t, lower by 67.4％than that for the conventional air liquefaction process, and the specific exergy consumption of liquid air production is 310.3kWh/t. With LNG cold energy utilization, the energy cost of liquid air production in this proposed process is 48.7% lower than that of conventional process. The optimal conditions are reached through the analysis of economic effectiveness.