Two-Stage Liquid Desiccant Dehumidification∕Regeneration

Air conditioning system based on liquid desiccant is a potential alternative to conventional vapor air conditioning system due to its advantages such as utilization of low temperature heat source, independently humidity and temperature control strategy and high energy storage capacity. In this paper, the technologies of two-stage liquid desiccant dehumidification which adopting LiCl solution and CaCl2 solution as the desiccant solution, is analyzed and applied in a new air conditioning system in Shanghai summer condition. The two-stage liquid desiccant dehumidification subsystem shows the advantages of easier regeneration and lower cost due to the application of CaCl2 compared with the LiCl alone dehumidification. A mathematical model is build to simulate its performance. It is found that the regeneration heat is reduced compared with LiCl alone dehumidification. The Tcop of the two-stage dehumidification applied in a hybrid system reaches 0.68. Two-stage liquid desiccant dehumidification is a feasible solution for dehumidification in Shanghai in China.