Preparation and performance testing of silica gel/ calcium chloride composite adsorbents for waste heat adsorption refrigeration

To develop a high performance adsorbent for waste heat adsorption refrigeration, a series of composite adsorbents were prepared by soaking silica gel into the solution of calcium chloride in vacuum, and their adsorption isotherm and adsorption rate were tested by experimental method. The testing results indicate that both the adsorption quantity and adsorption rate of composite adsorbents increase greatly compared to silica gel. The water uptake of composite adsorbent is 15.64g/100g dry adsorbent at the relative humidity of 20% in 2h,which is 8.06 times of silica gel under the same condition. Then, an adsorption chiller is produced using composite adsorbents. The performance testing of adsorption chiller shows that the cooling capacity, SCP and COP is 0.705kW, 70.51W/kg and 0.25, respectively, when hot water temperature, cooling water temperature and circulation time is 90°C, 35°C and 15min.