STUDY ON APPLICATION OF A HEAT PUMP SYSTEM TO GRAIN DRYING

摘要

To reduce fossil fuels consumed during grain drying, we studied the application of a heat pump, especially focusing on its installation in a recirculating grain dryer. The heat pump system we tested consists of a heat pump water heater, a hot water storage tank and a water-to-air heat exchanger. The chief characteristic of this grain-drying system is that water acts as both a heat-storage and heat-transfer medium for grain drying.For rice drying, the specific energy consumption was 1.68 MJ/kg-H2O, which is 68% lower than that of an average recirculating grain dryer using a kerosene burner.Our results confirm that our heat pump grain dryer can cut energy consumption and contribute to reducing greenhouse gas emissions.