Experimental Investigation of a Solar Energy Drying System in Conjunction with Air Source Heat Pump

Raw mineral materials drying is a high energy consumption processing in metallurgy industry. In order to reduce the energy consumption of purified arenaceous quartz drying, a novel solar energy drying system in conjunction with air source heat pump is developed. Based on the component design and system optimization matching, a solar energy drying system in conjunction with one air source heat pump unit (SEDS-ASHP) was designed and built. The SEDS-ASHP has been put into experimental operation successfully. Field tests on the SEDS-ASHP were performed under all kinds of typical climate conditions in Kunming, Yunnan Province of China. Test results show that, under the climatic conditions of daily solar radiation being about 15.3 to 21.6MJ/m², the SEDS-ASHP can furnish 40 to 65 °C hot air for arenaceous quartz drying. For the solar air collector, the instantaneous efficiency varies within about 0.36 to 0.64, the daily is about 0.34 to 0.53. For the air source heat pump unit, the average COP (coefficient of performance) varies within the range of 2.5 to 3.6. Compared with conventional electric dryer, the SEDS-ASHP is economical feasible. In areas with abundant solar resources, the SEDS-ASHP may provide an effective way for raw mineral materials drying.