Determination of Specific Moisture Evaporation Rate, Energy Consumption and Specific Energy Consumption at Varying Sample Load Capacity per Batch Drying in a Heat Pump Dryer

The study is to determine the specific moisture evaporation rate (SMER),energy consumption and specific energy consumption in heat pump drying at varying sample load capacity per batch drying. Three test sample loads were experimented, namely: 170g, 340g and 510g which were dried in the heat pump dryer at a drying temperature of 40 oC and drying air velocity of 0.7 m/s. Mango was used in the experiment as a test sample product. The energy consumed was determined in the kilowatt-hour meter from the measured value, specific moisture evaporation rate, and the specific energy consumption for both wet and dry products were calculated using the measured data. The results showed that 408.6g, 835.1g and 1342.4g of water were evaporated and 14.9 kWh, 13.2 kWh and 12.5kWh of energy were consumed and the calculated SMER were 0.0274 kg/kWh, 0.0633 kg/kWh and 0.1074 kg/kWh for 170g, 340g and 510g test sample loads per batch drying respectively. It was found that the specific energy consumption for both wet and dry products were 21.9 kWh/kg, 9.9 kWh/kg, and 6.1 kWh/kg of wet product and 54.9 kWh/kg, 26.8 kWh/kg, and 17.9 kWh/kg of dry product for 170g, 340g and 510g, respectively. The results indicate a reduction in the energy consumption as the sample load increased.