An experimental analysis of solar-assisted chemical heat pump dryer

摘要

The performance of a solar-assisted chemical heat pump dryer has been studied under the meteorological conditions of Malaysia. The system consists of four mean components: solar collector (evacuated tubes type), storage tank, solid-gas chemical heat pump (CHP) unit and dryer chamber. A solid-gas CHP unit consists of a reactor, condenser and evaporator. The reaction (CaCl_2-NH_3) has been used in this study. A series of experiments have been performed on the system under varied conditions for two days. The maximum values of solar fraction from the experiments on clear and cloudy days are 0.713 and 0.322, respectively; whereas the coefficient of performance of CHP (COP~h) maximum values of 2 and 1.42 are obtained from the experiments on clear and cloudy days, respectively. The total system energy output from the experiment on a clear day is 51 kWh against 25 kWh on a cloudy day. Any reduction of energy at the condenser as a result of decrease in solar radiation will decrease the coefficient of performance as well as the efficiency of drying.