A comprehensive review of low dew-point desiccant wheel system: Mechanisms, configuration, and optimization

Humidity control is very important in production and life, especially in low dew-point industries where the dew-point temperature is less than 0 °C. A low dew-point desiccant wheel system (LDDWS) can meet the ambient humidity ratio required for production well. The mechanisms, configuration, and optimization of the LDDWS are comprehensively reviewed. The air heat-moisture handling processes of the LDDWS are initially introduced. The influence of the cold and heat source configurations on the dehumidification capacity and energy consumption is illustrated. Free cold sources, renewable heat sources, and heat pump technology can effectively increase energy utilization, thereby reducing refrigeration consumption and promoting energy savings. The optimization measures of system performance, including efficient desiccant materials, desiccant wheel partitioning, heat recovery technology, and low dew-point return air recycling, are presented. These optimization measures can effectively improve the dehumidification capacity and reduce the consumption of primary energy. In addition, to enhance the further development of LDDWS, this paper presents prospects for future developments in terms of industrial demand, dehumidification capacity, thermodynamic cycle and energy utilization.