The working principle of the drying equipment is to vaporize and escape the moisture in the material (generally referring to moisture or other volatile liquid components) through heating to obtain a solid material with a specified moisture content. Specifically, the working principle of drying equipment can be divided into two types: conduction drying and convection drying.
Conduction drying refers to placing the material on a heating plate, through which the heat is conducted into the material, so that the moisture or other liquids inside it volatilize. This drying method is suitable for some relatively small materials, such as powder, granules, etc. The advantage of conduction drying is that the drying speed is fast and the material can be dried in a short time, but its disadvantage is that the heat control is more difficult, which is easy to cause excessive drying or uneven heating of the material.
Convection drying refers to the use of convective media such as hot air or hot steam to directly contact the material to transfer heat to the material and evaporate the water in it. Convection drying is suitable for various types of materials, such as granules, flakes, strips, etc. The advantage of convection drying is that the heat is easy to control and can avoid over-drying or uneven heating of the material, but it has the disadvantage that the drying speed is relatively slow.
In addition, there are some special drying methods, such as vacuum drying, freeze drying, etc. Vacuum drying is drying in a vacuum environment, which is suitable for some materials that are sensitive to oxygen or easy to oxidize. Freeze drying is to freeze the material into a solid state, and then sublimate the moisture in the solid material into a gaseous state in a vacuum environment, so as to achieve the purpose of drying. In short, the working principle of the drying equipment is to vaporize and escape the moisture in the material through heating to obtain a solid material with a specified moisture content. Different drying methods have different working principles and scope of application, and need to be selected according to specific materials and drying requirements.