Experimental and Theoretical Study of Liquid Desiccant Dehumidification System by Using the Effectiveness Model

Abstract

Desiccant evaporation cooling technology is compatible with the environment and can be used as an air conditioner in the indoor environment of the buildings. The characteristics of dehumidification column of the liquid desiccant evaporation cooling air conditioning system (LDCS) are introduced in this paper. This system was designed and manufactured for this purpose. Lithium chloride (LiCl), as liquid desiccant, and a packed bed column were used for the dehumidification. The described system includes a part for processed air simulation in various temperatures, humidities, and flow rates. The effectiveness model, based on heat and mass transfer equations, is considered for predicting performance of the lithium chloride dehumidification system. For validation purpose, a comparison was performed between experimental outlet data of the system and the corresponding results of the experimental model that showed a satisfactory correlation i.e., increase in the mass transfer unit number (NTU) leads to a better performance of the dehumidification system. In addition, factors leading to increase in NTUs are also investigated.