Drying Characteristics of High Temperature Heat Pump in China

< P > (1) Energy saving

< P > Energy saving is the starting point and main advantage of heat pump. Heat pump can save 40%-70% of energy consumption when drying wood at low temperature (15-65 C). The optimum temperature for drying rice is 35-50 C. The temperature is low, but it needs a lot of heat. The efficiency of traditional dryer is only 3%-5%, but the efficiency of heat pump dryer will be improved obviously. Cloth has strict requirements for drying temperature. Heat pump drying unit can not only meet this requirement, but also save about 50% energy than traditional heat pump drying unit. The application of heat pump drying technology in vegetable dehydration can save energy up to 90%.

(2) Drying products with good quality

heat pump drying is a mild drying method, close to natural drying. The evaporation rate of surface water is close to that of internal water moving to the surface, which makes the dried products of good quality, good color and high grade. The aromatic volatile substances obtained by ordinary drying method have little retention, low vitamin retention with poor heat resistance and large color change. For example, the retention rate of ginger obtained by drum dryer is only 20%, while the retention rate of ginger obtained by heat pump dryer is as high as 26%.

(3) Drying parameters are easy to control and adjustable in a wide range

heat pump drying process, the temperature, humidity and circulating flow of circulating air can be accurately and effectively controlled, and the range of temperature regulation is - 20-110 (+auxiliary heating device), and the range of relative humidity regulation is 15%-80%. It is suitable for drying heat sensitive materials.

(4) Environmentally friendly

Drying of materials requires not only improving product quality and saving energy consumption, but also being environmentally friendly. Based on the same evaluation criteria, the impact of heat pumps on global warming is very small compared with the carbon dioxide released by electricity. Environmentally friendly is the advantage of heat pump drying. At present, heat pump is advocated to reduce carbon dioxide emissions abroad, and it will be further applied.