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The types and characteristic of the air dryer

2021-09-01
The type of the air dryer 
There are two categories of air dryers: adsorption and refrigeration. Adsorption compressed air dryer uses the principle of pressure swing adsorption. When wet air passes through adsorbent, water is adsorbed to obtain dry air; Based on the principle of cooling air and reducing air temperature, the frozen compressed air dryer separates the water in the wet air from the air after condensation to obtain dry air.


What are the characteristics of air dryer

The air dryer can be classified according to different characteristics such as operation process, operation pressure, heating mode, wet material movement mode or structure. 
According to the operation process, air dryers are divided into intermittent (batch operation) and continuous types;

1.According to the operating pressure, air dryers are divided into atmospheric air dryers and vacuum air dryers. Operating under vacuum can reduce the moisture vapor partial pressure of the space and accelerate the drying process, reduce the moisture boiling point and material drying temperature, and the steam is not easy to leak out. Therefore, vacuum air dryers are suitable for drying with heat sensitivity, easy oxidation Occasions where explosive and toxic materials and wet steam need to be recovered.
2.According to the heating mode, air dryers are divided into convection, conduction, radiation, dielectric and other types. Convective air dryer, also known as direct air dryer, uses hot drying medium to directly contact wet materials to transfer heat by convection and take away the generated steam; The conductive air dryer is also called indirect air dryer. It uses the conduction method to transfer heat from the heat source to the wet material through the metal partition wall. The generated wet steam can be removed by decompression suction, a small amount of purge gas or condensation on the surface of a separate low-temperature condenser. This kind of air dryer does not use drying medium, has high thermal efficiency and products are not polluted, but its drying capacity is limited by the heat transfer area of metal wall and its structure is complex. It is often operated under vacuum; Radiant air dryer uses various radiators to emit electromagnetic waves in a certain wavelength range, which are selectively absorbed by the surface of wet materials and transformed into heat for drying; Dielectric air dryer uses high-frequency electric field to dry wet materials with thermal effect.

3.According to the movement mode of wet material, the air dryer can be divided into fixed bed type, stirring type, spray type and combined type. According to the structure, the air dryer can be divided into air dryer, conveyor air dryer, drum air dryer, vertical air dryer, mechanical stirring air dryer, rotary air dryer, fluidized bed air dryer, air flow dryer, vibrating air dryer, spray air dryer. And combined air dryer.