Automatic drying equipment is an indispensable mechanical equipment in the process of industrial production and manufacturing. It is widely used in various industries such as agricultural and sideline product processing, Chinese medicinal materials drying, industrial chemical raw material processing, and building materials processing. Therefore, there are many types of drying equipment. At present, the more commonly used drying equipment in industrial and agricultural drying production processes mainly includes microwave drying equipment, multi-layer mesh belt drying equipment, heat pump drying room and freeze drying equipment. The following are the types and characteristics of different drying equipment.
1. Microwave drying equipment: Microwave drying equipment mainly uses microwave energy to make the water molecules inside the material move back and forth at a directional high frequency, causing the water molecules to rub against each other to form a heating body, so that the entire material forms a heating body, and realizes the fast, uniform and efficient drying of water-containing materials. Microwave drying equipment can be used for drying, heating, maturation, and killing functions. Compared with other drying equipment, the most important feature of microwave drying equipment is that it can sterilize during the drying process, improve the shelf life and quality of the product, and has a fast heating speed, energy saving and high efficiency, automatic continuous drying, and uniform drying. Generally, it is mainly used for drying and sterilizing high value-added materials in the food industry, drying insects, drying low-moisture chemical products, tea fixing, drying building materials, heating lunch boxes, etc. It is not suitable for drying high-moisture vegetables and fruits, so it is often used together with muti-layer dryers and heat pump drying machine to sterilize common materials before packaging after drying.
2.Heat pump drying machine: It mainly consists of a drying room host, an air-energy heat pump, a trolley material rack, an electronic control system and other equipment. It mainly uses the host to send the pure hot air provided by the heat pump into the drying room through the fan, so that the air in the drying room can circulate and form wind evaporation on the surface of the material, and then the humid and hot air in the drying room will be discharged through the circulating fan. The hot air recovery device in the drying room will send the dehumidified dry hot air back into the dryer for such a reciprocating cycle, thereby achieving the purpose of drying the material. Since the drying room is a closed space, it can accurately control the temperature, so the equipment has the advantages of good and stable drying quality, energy saving and environmental protection, simple operation, etc. Since the materials are placed in the drying room for static drying and the temperature can be accurately controlled, the equipment drying temperature is usually between 20-80℃, which is very suitable for drying fruits, vegetables, mushrooms, fungus, medicinal materials, seafood, etc.
3.Vacuum freeze drying equipment: The vacuum freeze dryer mainly uses the working principle of freeze sublimation drying. It mainly freeze-dries the materials in a vacuum, and then heats them to make the water in the materials directly sublimate to achieve the purpose of drying the materials. The quality of materials using freeze drying is very high, because it can ensure that the materials after dehydration are almost unchanged compared with the raw materials, and the properties and characteristics of the materials can be completely retained. Therefore, the freeze dryer equipment is mainly used in the field of food and medicine. However, due to the high price of this equipment, the equipment is more suitable for materials with high drying quality requirements and high added value, and it is not suitable for some materials with low drying requirements and low added value.
4.Multi-layer mesh belt dryer: Multi-layer mesh belt dryer, also called box-type dryer, is mainly composed of dryer body, heat source equipment, conveyor belt, feeding and discharging system, electronic control system and other accessories. Its working principle is mainly to spread the materials placed on the conveyor belt through the material leveler, and then the transmission device drags the materials to move back and forth inside the dryer. The hot air enters from the bottom of the dryer and passes through the multi-layer mesh belt and materials layer by layer, and takes away the moisture in the materials. The water vapor is discharged through the top, so as to achieve the purpose of drying the materials. The multi-layer mesh belt dryer has the advantages of large drying output and high efficiency. Since the multi-layer mesh belt dryer is a continuous dynamic drying material, it is more suitable for the dehydration and drying of various rhizomes, leaves, fruits, flakes, blocks, powders and other Chinese medicinal materials and agricultural industrial raw materials with large drying output and low water content and low drying quality requirements. It is not suitable for drying materials with small drying output or high water content.
