Effect of Matrix Properties on the Performance of a Counterflow Rotary Dehumidifier

Abstract

A finite difference model of a counterflow rotary dehumidifier is used to determine the effect of six matrix properties of dehumidifier performance. The matrix properties considered are the sorption isotherm shape, the maximum sorbent water content, the heat of sorption, the matrix thermal capacitance, matrix moisture diffusivity, and sorption isotherm hysteresis. The isotherm shapes and the sorption parameter values are selected to be representative of available insoluble desiccants. The results of the finite difference calculations show that the shape of the isotherm has a greater effect on dehumidification than the maximum water content. Large adsorption heat effects or matrix thermal capacitance has a detrimental impact on dehumidification. Hysteresis in the adsorption isotherm significantly impairs dehumidifier performance. The anlaysis shows that commercially available solid desiccants can result in nearly optimal dehumidifier performance.