Experimental study on combined heat and mass transfer of the lithium chloride aqueous solution for a plate type dehumidifier

Liquid desiccant systems are drawing more attention because of its advantages in energy saving and environmental friendliness. The use of the liquid desiccant systems offers design and performance advantages over the solid desiccant systems, especially when solar energy is used for regeneration. The objective of this paper is to analyze the combined heat and mass transfer characteristics of lithium chloride aqueous solution for a plate type dehumidification system with grooves on the plate surface. The use of grooves on the plate surface increases the solution wettability, and decreases the solution scattering on the plate surface. The plate surface is treated with a hydrophilic coating to enhance the wettability of the solution. The generated heat during the absorption process is absorbed by the coolant in the internal channels of the plates. The interface stability depends on the stable liquid film thickness at the plate surface. The coolant flows from the bottom to the top in the channels, while the lithium chloride aqueous solution flows from the top to the bottom on the plate surface, and the air flows between the vertical plates which is in a cross flow to the solution. The effect of the inlet conditions of the moist air, solution and coolant on the dehumidification performance are analyzed in this study.