Parametric studies on coupled columns of liquid desiccant-vapor compression hybrid air conditioning system

A coupled system of two liquid desiccant columns-one dehumidifying the air and the other regenerating the solution-has been investigated for very low solution to air flow ratios (S/A) in the range of 0.2-1.6%. The present study explores the feasibility of integrating the columns with the conventional room air conditioner (AC) to enhance the dehumidification capacity of the hybrid AC system. The air inlet conditions to dehumidifying column are assumed typical of supply air from a room AC at 8-16°C dry bulb temperature (DBT) and 75-95% relative humidity. Similarly, inlet air to regenerating column is assumed at 40-60°C DBT and 15-20 g/kg specific humidity, which are typical of the condenser exit air. It is observed that the moisture transfer from supply to condenser air takes place at the rate of 0.28-0.6 g/s for a 0.8 TR AC unit. This indeed enhances the dehumidification of the supply air considerably. Moreover, the supply air gets sensibly heated following the isenthalpic dehumidification process, which enables the hybrid system to maintain low humidity in the conditioned space. © The Author 2011. Published by Oxford University Press. All rights reserved.