Experimental Investigation on Performance of Multi-Stage Dehumidification Heat Pump Tower Corn Drying System in High Cold Regions

Abstract

In view of the problems of high energy consumption and heavy pollution in the drying process of large-scale multi-stage tower coal-fired corn in Northeast China, combined with the high cold characteristics of the regions, a multi-stage series dehumidification heat pump tower corn drying system was proposed, and a demonstration application project was established. The performance and life-cycle costs of the system were experimentally evaluated and compared to a traditional coal-fired corn drying tower. The results show that the system can achieve a supply air temperature above 68 °C under the ambient temperature of −20 °C. The total energy consumption of the system per hour is 595.5 kWh, and the specific moisture extraction rate reaches 3.39 kg/kWh. Moreover, the coefficient of performance of heat pump units reaches 3.0 − 6.3. Due to the attractive energy-saving potential, the operational cost-effectiveness of the multi-stage series dehumidification heat pump tower corn drying system can contribute to cut-down of life-cycle cost. It has been found that the life-cycle cost of the multi-stage series dehumidification heat pump tower corn drying system is 40.5% lower than that of the traditional coal-fired corn drying tower.