Welcome Lisong industrial technology Co., ltd !

News

Injection molding machine manufacturers: what is the working principle of the dryer

TIME:2021-03-09 Share

Dryer is a kind of mechanical equipment that uses heat energy to reduce the moisture 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 a solid material with a specified moisture content. The purpose of drying is for material use or further processing. For example, the drying of wood before making wooden molds and woodware can prevent product deformation, and the drying of ceramic blanks before calcination can prevent the finished product from cracking. In addition, the dried materials are also easy to transport and store, such as drying the harvested grain to a certain moisture content to prevent mildew. Since natural drying is far from meeting the needs of production development, various mechanized dryers are more and more widely used.

The working principle of the dryer:
The drying process needs to consume a lot of heat energy. In order to save energy, certain materials with high moisture content, suspensions or solutions containing solid substances are generally dehydrated or heated to evaporate mechanically, and then dried in a dryer to obtain dry solids.
During the drying process, it is necessary to complete the transfer of heat and quality (moisture) at the same time to ensure that the partial pressure (concentration) of moisture on the surface of the material is higher than that in the external space, and to ensure that the heat source temperature is higher than the material temperature.
The heat is transferred from the high-temperature heat source to the wet material in various ways, so that the moisture on the surface of the material is vaporized and dissipated to the outside space, so that the difference in moisture content appears on the surface and inside of the material. The internal moisture diffuses and vaporizes to the surface, so that the moisture content of the material is continuously reduced, and the overall drying of the material is gradually completed.
The drying rate of the material depends on the surface vaporization rate and the diffusion rate of internal moisture. Generally, the drying rate in the early stage of drying is controlled by the surface vaporization rate; then, as long as the external drying conditions remain unchanged, the drying rate and surface temperature of the material remain stable. This stage is called the constant-rate drying stage; when the moisture content of the material decreases to a certain level When the diffusion rate of internal moisture to the surface decreases and is less than the surface vaporization rate, the drying rate is mainly determined by the internal diffusion rate, and decreases continuously with the decrease of moisture content. This stage is called the reduced-rate drying stage.

Related News
Related Product
LI SONG Injection Molding Machine-TECHNICAL & SPECIALTY

2020 Star Of Injection Molding Machine Manufacturer!

Please write it
kevin@lisonginc.com
TOP