Effectiveness of moisture removal for an adiabatic counterflow packed tower absorber operating with CaCl2-air contact system

In the open cycle desiccant cooling system, the room air or the room air mixed with ambient air is drawn through the desiccant dehumidifier where water vapor is absorbed. Then the dry air is cooled by a sensible heat exchanger by passing the air through an evaporative cooler. The desiccant may be either solid or liquid. Liquid desiccant systems are not as well developed as solid desiccant systems. Any attempt to improve the performance of a liquid desiccant should include a performance analysis of the dehumidifier. One of the efficient dehumidifiers for the liquid desiccant system is the packed bed dehumidifier and shown schematically. Because of the abundance of variables involved with the packed bed dehumidifier, the analysis becomes increasingly complex and is achieved at very high computational cost. Hence there is a need to define the performance of a packed bed quantitatively. A definition of air moisture removal effectiveness is presented based on the rigorous heat and mass transfer calculations for an adiabatic counterflow packed bed dehumidifier. This note also studies the influence of relevant parameters on tower performance quantified by the moisture removal effectiveness.