Terminology of adsorption dryer

1. Adsorption balance

When compressed air comes into contact with a porous solid adsorbent, the water molecules are adsorbed after touching the surface of the solid adsorbent. At the same time, the adsorbed water molecules collide with the external gaseous molecules due to their own molecular thermal movement, and some of the water molecules leave the solid surface and return to the gas phase. Adsorption equilibrium is reached when the number of water molecules adsorbed is equal to the number of water molecules leaving the surface of the adsorbent. Adsorption equilibrium is a dynamic equilibrium, and adsorption is no longer generated at the macroscopic level, but adsorption and desorption at the microscopic level are still ongoing.

2. Adsorption capacity

The adsorption capacity is divided into static adsorption capacity and dynamic adsorption capacity. The static adsorption capacity is the amount of gas adsorbed per unit mass adsorbent when the adsorbent and the adsorbent reach full equilibrium, that is, when the adsorption is equilibrium, the unit is mol/g or g/g.

3. Pressure dew point

Pressure dew point refers to the saturated water content at this temperature, usually under the same conditions, the lower the dew point, the smaller the water content. When the humid air is compressed, the density of water vapor increases and the temperature rises. When the compressed air cools, the relative humidity increases, and when the temperature continues to drop to 100% relative humidity, water droplets precipitate from the compressed air, and the temperature at this time is the "pressure dew point" of the compressed air. The dew point is also the temperature value in degrees Celsius.

4. Isothermal adsorption line

At a certain temperature, the relationship between the adsorption capacity and the partial pressure of water vapor is called the isotherm adsorption line.

5. Equal amount adsorption line

Under a certain adsorption capacity, the relationship between equilibrium pressure and temperature is called an equal adsorption line.

6. Adsorption heat

Adsorption heat is the thermal effect that occurs when the adsorbate comes into contact with the adsorbent. The adsorption process is an exothermic process, and the analytical process is an endothermic process, and the adsorption heat can accurately express the activity of the adsorbent and the strength of the adsorption capacity.

7. Adsorption-regeneration

For the compressed air adsorption drying device, when the adsorption process reaches an equilibrium state, the adsorbent loses its adsorption effect on the water vapor of the compressed air, and it must be analyzed to make it have the adsorption function again, this process is called the regeneration of the adsorbent.