Effects of gas-gas heat exchanger on improving the performance of solar regenerator

The low energy efficiency of solar regenerator has been a common concern in the solar evaporation- dehumidification cooling system. In order to enhance the energy utilization efficiency, a gas-gas heat exchanger was used as an additional heat-recycle unit to capture residual heat from hot air. Two types of regenerators with（GGHEW）and without（GGHEN）gas-gas heat exchanger were studied and their performances were compared. The results showed that both dehumidification capability and efficiency of regenerator were enhanced with the increase of the temperature of water heated by solar energy. The basic performance of regenerator was significantly improved by adding gas-gas heat exchanger. Dehumidification capability of GGHEW was in a range from 40 to 55 g/kg, which was 35-45 g/kg more than that of GGHEN. The regeneration efficiency of GGHEW could reach up to 60% at 90℃ of hot water, which was 30%-50% higher than that of GGHEN. It was concluded that installation of gas-gas heat exchanger on the solar regenerator can improve the solar energy utilization efficiency and the regeneration efficiency, which indicates that heat recycle is necessary for solar regenerator.