Experimental study on liquid desiccant regeneration by photovoltaic electrodialysis

Abstract

Abstract Liquid desiccant regeneration is an important part of liquid desiccant air conditioning system and consumes the majority of the system’s power. Conventional methods for liquid desiccant regeneration use thermal energy to regenerate the liquid desiccant. One of the biggest problems for thermal regeneration is that the liquid desiccant should be cooled down before dehumidification. Furthermore, the efficiency for liquid desiccant regeneration drops under high temperature and humidity climates. In comparison, electrical regeneration, such as electrodialysis (ED), may solve the problems above. No phase change is involved in this process. In addition, low electrical energy is required and photovoltaic power is capable of proving the necessary energy. In this paper, the performance of liquid desiccant regeneration by photovoltaic electrodialysis (PV-ED) was experimentally investigated by considering two important factors, including the initial desiccant concentration and current intensity. The results showed that the initial desiccant concentration and current intensity had big impact on the performance of the system. Lower desiccant concentration and higher current intensity contributed to the current efficiency and solute transport, respectively. In addition, the energy consumption per unit solute migration increased with the increase of both current intensity and desiccant concentration. The results also indicated that the PV-ED regenerator performed better when the initial desiccant concentration was low and current intensity was high.