Performance analysis of a cascade lithium bromide absorption refrigeration/dehumidification process driven by low-grade waste heat for hot summer and cold winter climate area in China

Recovery of low-grade waste heat has great potential to reduce energy consumption around the world. In this paper, a novel cascade lithium bromide absorption refrigeration/dehumidification system is developed to recover low-grade waste heat with temperature range from 90 degrees C to 150 degrees C for dehumidification in hot summer and cold winter climate area of China. This system consists of two subsystems: lithium bromide absorption refrigeration system and lithium chloride liquid dehumidification system. The low-grade waste heat is applied by two subsystems in a cascade approach. The key parameters in terms of air temperature, air humidity, solution concentration, and solution temperature are investigated to obtain the optimization design of the proposed system. Performance of the proposed system is analyzed for different refrigeration temperatures. The results show that the max coefficient of performance for the proposed system is 0.6029. The moisture removal rate and the humidity efficiency are 20.20 g/kg and 0.9385. The novel coupling system develops a creative and efficient way to recover low-grade waste heat for dehumidification in hot summer and cold winter climate area of China.