1. It can realize low-temperature air closed cycle drying, and the material drying quality is good. By controlling the working conditions of the device, the temperature of the hot dry air in the drying room is between 20 and 80 ℃, which can meet the high-quality drying requirements of most heat-sensitive materials; the closed circulation of the drying medium can avoid the exchange with the outside air. The impurities that may be brought to the material are contaminated, which is especially important for food, medicine or biological products. In addition, when the material is sensitive to oxygen in the air (easy to oxidize or burn and explode), an inert medium can be used instead of air as the drying medium to achieve oxygen-free drying.
2. High efficiency and energy saving. The heat of the heated air in the heat pump dryer mainly comes from the sensible heat and latent heat contained in the warm and humid air discharged from the recovery drying chamber. The energy that needs to be input is only the power consumption of the heat pump compressor, and the heat pump consumes a small amount of power to produce The advantage of taking a lot of heat, so the heat pump drying device SMER (the moisture content in the wet material removed by the unit energy consumption) is usually 1.0~4.0kg/kWh, while the SMER value of the traditional convection dryer is about 0.2~0.6kg/kWh.
3. Convenient temperature and humidity control. When the material has high requirements on the temperature and humidity of the air entering the drying room (such as wood, etc.), the evaporation temperature and condensation temperature of the working fluid in the evaporator and condenser can be adjusted to meet the material's texture and appearance. Claim.
4. Useful and volatile components in recyclable materials. Some materials contain volatile components (such as fragrance and other volatile components). When a heat pump is used for drying, the volatile components and moisture vaporize into the air together in the drying room, and the air containing volatile components passes through the evaporator. When it is cooled, the volatile components are also liquefied and discharged together with the condensed water. Collect the condensed water containing the volatile components and separate the useful volatile components by appropriate methods.
5. Environmentally friendly. The drying medium in the heat pump drying device circulates in a closed loop, and there is no pollution caused by material dust, volatile substances and odors discharged into the environment with the drying exhaust gas; the waste heat in the exhaust gas of the drying chamber is directly recovered by the heat pump to heat the cold and dry air. Thermal pollution of the unit to the environment.
6. Multifunctional can be realized. The heat pump in the heat pump drying device also has a refrigeration function. The refrigeration function can be used to realize low-temperature processing (such as quick freezing and refrigeration) or preservation of a variety of materials in the season with fewer drying tasks. It can also expand the heating function of the heat pump in the cold Season for planting (such as greenhouse) or breeding grounds for heating.
7. The heat pump dryer is suitable for a wide range of materials. The materials suitable for drying are mainly a large class of materials that can withstand temperatures between 20 and 80 ℃ during the drying process, or materials that can withstand higher temperatures but are more energy-saving or safer by heat pump drying. Materials that have been studied and applied more such as wood (such as oak), grains, seeds, edible fungi (such as mushrooms, fungus), medicinal materials (such as ginseng, etc.), seafood (such as fresh oysters, scallops, etc.), biologically active products ( Such as cells, enzymes), tea, paper, etc.
8. Compared with other low temperature (air temperature entering the drying chamber <40℃) drying device (such as microwave drying, vacuum drying, freeze drying), due to the small initial investment in equipment and low operating costs, the heat pump dryer device has obvious economic advantages Sex. The equipment cost of the heat pump drying device is mainly the heat pump part and the drying chamber part, where the drying chamber part has the same requirements as the ordinary convection drying chamber, and there is no special air tightness and pressure resistance requirements.
9. Compared with ordinary drying devices (air temperature entering the drying room>40℃), the initial investment of heat pump dryers is generally higher than that of electric air heating devices, gas or coal-fired hot blast stoves, so the initial investment of drying devices is generally higher than Ordinary drying device, heat pump dryer drying device has high energy efficiency, low operating cost, and its comprehensive economy still has certain advantages.