Comparison of Liquid Desiccants for Air Cooling Systems Using Wetted Wall Column

Desiccant dehumidification refers to the use of chemical for absorption of water vapor to dehumidify air, and thus reduce the latent cooling load in a building's Heating, Ventilation and Air-Conditioning system. There are two types of desiccant systems: liquid and solid. Liquid desiccant systems remove more moisture from air than the dry desiccant systems. Some of the commonly used liquid desiccants include lithium bromide and lithium chloride. The paper presents a comparative analysis of three desiccants, namely, calcium chloride, lithium chloride and potassium formate. Calcium chloride and lithium chloride are commonly used whereas potassium formate is a new desiccant. The wetted wall column is used to study the dehumidifying property of each chosen desiccant. The gas enters in a counter-current fashion allowing gas-liquid contact. The analysis is used to understand the variations in the dehumidifying nature of the desiccants.