It refers to a mechanical device that uses thermal energy to reduce the moisture content of materials and is used to dry objects. The dryer vaporizes and escapes the moisture in the material (generally refers to moisture or other volatile liquid components) by heating to obtain solid materials with a specified moisture content. The purpose of drying is for the needs of material use or further processing. According to the operating pressure, the dryer is divided into two types: atmospheric pressure dryer and vacuum dryer. According to the operating pressure, it can be divided into atmospheric pressure and reduced pressure (decompression dryer is also called vacuum dryer). The entry also details adsorption dryers, freeze dryers and microwave dryers.
According to the operating pressure, air dryers are divided into atmospheric air dryers and vacuum air dryers. Operating under vacuum can reduce the partial pressure of moisture vapor in the space and accelerate the drying process, and can reduce the boiling point of moisture and the drying temperature of materials. The steam is not easy to leak out. Therefore, vacuum air dryers are suitable for drying heat sensitive, oxidizable, explosive and toxic materials and occasions where moisture vapor needs to be recovered;
The future development of air dryer will develop and improve the air dryer under the condition of in-depth study of drying mechanism and drying characteristics of materials and mastering the optimal operating conditions for different materials; In addition, large-scale, high strength, high economy, and improving the adaptability to raw materials and product quality are the basic trends of the development of air dryers; At the same time, further research and develop new air dryers with high efficiency and special requirements, such as freeze dehumidifiers, rotary dehumidifiers and air freeze dryers.
The development of air dryer should also pay attention to energy conservation and comprehensive utilization of energy, such as adopting various combined heating methods, transplanting heat pump and heat pipe technology, developing solar air dryer, etc; The automatic control technology of air dryer should be developed to ensure the realization of optimal operating conditions; In addition, as human beings attach importance to environmental protection, improving the environmental protection measures of the air dryer to reduce the leakage of dust and exhaust gas will also be the direction that needs in-depth research.