Energy saving and emission reduction solution for agricultural drying - Kcalin dryer equipment

Energy conservation and emission reduction of agricultural drying

The air source heat pump drying unit has obvious technical advantages in the field of agricultural drying. We know that agricultural products are rich in vitamins, protein, sugar and other nutrients, especially fresh agricultural products are rich in water. In order to facilitate storage, processing and transportation, drying operation is usually adopted.

Traditional conventional agricultural products are dried by coal-fired or gas-fired boilers. However, due to the different types of agricultural products and the different proportion of water and other nutrients, the quality of drying is difficult to control, and the cost is high. Coal, gas and other energy sources are easy to cause secondary pollution to the environment and products, which is contrary to the policy guidance of clean environmental protection and low-carbon energy conservation.

The air-source heat pump drying unit uses the energy in the air as the energy source, which is cleaner, environmentally friendly, low-carbon and energy-saving. It not only solves the problem of air pollution caused by conventional drying methods such as coal and gas, but also greatly improves the drying quality and efficiency.

The main components of Kcalin dryer equipment are compressor, evaporator, expansion valve and condenser. The refrigerant in the evaporator absorbs the heat of the hot and humid air from the drying medium in the drying room, so that the hot and humid air cools and dehumidifies the drainage water into the cold and dry air, and the temperature and relative humidity are reduced. The refrigerant in the evaporator changes from liquid to gas due to absorbing the heat of hot and humid air, and is sent to the condenser after being compressed and heated by the compressor. The refrigerant in the condenser is cooled to high temperature and high pressure liquid by dry and cold air from the evaporator. At the same time, the heat released by the refrigerant in the condenser reheats the dry and cold air into dry and hot air, which is sent back to the drying room to heat the dry material, and absorbs the moisture of the dried material with adiabatic isoenthalpy. The high pressure and high temperature refrigerant liquid from the condenser decreases from high pressure to low pressure through throttling devices such as expansion valve, and becomes a two-phase fluid with low temperature, which enters the evaporator to absorb heat and enter the next refrigeration dehumidification cycle. Since the heat pump drying unit recovers the low-grade waste heat of the drying medium while dehumidifying and drying, and then uses the recovered waste heat for drying and heating again after heating up and increasing the enthalpy, similar to the water pump that pumps water from the low water level to the high water level, the heat pump drying unit is an energy-saving drying equipment, and the energy saving rate is 40%~70% compared with the conventional drying equipment.

Characteristics of heat pump agricultural drying technology

1.Energy Saving

Higher energy utilization rate, lower operating cost and shorter drying time. The heat pump drying process is basically carried out in a closed system. The drying process recycles the sensible heat and latent heat in the exhaust gas, effectively reducing the energy loss. For example, compared with traditional drying, the energy saving rate of wood drying with heat pump is generally about 40%.

2.High drying quality

Heat pump agricultural drying technology generally belongs to low-temperature drying, and the drying environment is easy to control. It is suitable for drying most heat-sensitive materials such as agricultural products, food and medicine. Compared with traditional drying methods, the oxidation and chemical decomposition of agricultural products are significantly reduced and the drying quality is high.

3.Environmentally friendly

The air-source heat pump drying unit uses the energy in the air as the heat source, which is cleaner and more environmentally friendly. The use of air source heat pump drying can significantly reduce environmental pollution and reduce the impact on global warming.

4.High degree of automation

During the operation of the heat pump drying unit, due to the installation of various types of sensors and control devices, the temperature, humidity, flow and other parameters of the drying medium in the drying room can be controlled accurately, which greatly improves the automation of the heat pump drying device.

Application scope of heat pump agricultural drying technology

1.It is applicable to materials with high added value and long drying cycle. For example, for wood drying, the drying cycle of high-grade precious wood and hard-dried wood is long, the energy-saving effect of heat pump drying is obvious, and the drying quality is good.

2.Because heat pump drying has obvious energy-saving effect at the stage of high moisture content of materials, it is more suitable to use heat pump to pre-dry materials.

3.Heat pump unit agricultural drying has better energy-saving effect in high temperature and humid areas.

4.The heat pump agricultural drying unit is recommended for seeds, aquatic products and heat-sensitive chemical raw materials suitable for low-temperature drying.

At present, heat pump drying units have been used in wood, food, grain, seeds, fruits and vegetables, tobacco and other industries in developed countries such as Europe and the United States. The economic benefits of the air source heat pump drying unit project of agricultural products have been seen, which is a key direction of the application of heat pump agricultural engineering.