Liquid desiccant materials and dehumidifiers - A review

It is important to decrease the energy cost of heating, ventilating and air conditioning (HVAC) systems without compromising indoor air quality and comfort conditions due to the rising cost of fossil fuels and other environmental concerns. Liquid desiccant cooling systems are one of the alternatives in this regard which is not only environmental friendly (no use of any refrigerant which deplete ozone layer) but at the same time make a good use of alternative sources of energy like, solar, biomass etc. This paper presents different commercially available liquid desiccants and their composites which combines the properties of two or more desiccant materials for better performance. A good desiccant should have better moisture absorption capability and lower temperature of regeneration. This paper also includes the different configurations of liquid desiccant dehumidifiers and their advantages as well as drawbacks. Some new configurations of liquid desiccant dehumidifiers have been introduced which greatly improves the system overall performance. Moreover, a summary of the performance parameters has been made to analyze the system performance. This review is meaningful for the research and technical development process of liquid desiccant technology.