How Does it Works
|How does it works?
Desiccant Dryer is based on the principle of heatless regeneration and the physical properties of desiccant to adsorb and desorb the water vapour. It uses pressure swing principle/purge air to generate the desiccant bed.
The Desiccant Dryer has two pressure vessels/towers filled with desiccant. While the air is dried in one tower/vessel, the desiccant in the other is regenerated, thus maintaining a continuous and automatic operation.
Drying: The wet compressed air is led into one of the adsorber towers through solenoid valves in the smaller models, and through pneumatically controlled valves in the bigger models. This wet compressed air is passed through a specially designed sieve tube for uniform flow of air through the desiccant tower, where it is dried. Part of this dried air is taken out and used for purging or reactivating the desiccant of the tower saturated with moisture. The balance dry air leaves the dryer through a check valve.
Regeneration: The purge air with a low water vapour pressure is passed over the desiccant (saturated with adsorbed moisture). The desiccant loses the adsorbed moisture which is expelled into the atmosphere via outlet valve through a muffler. Now the desiccant is dry and ready for adsorption. The heat of adsorption released during this process raises the temperature of the desiccant, which in turn stimulates the liberation of the adsorbed water vapour and thus, the regeneration.
Change Over: After a preset time, the desiccant in the first tower needs to be regenerated as it is saturated with the adsorbed moisture. The outlet purge air valve of the second tower is energised in a sequence, where the outlet valve closes first to pressurise the adsorbent in the tower in regeneration mode. The second tower now becomes the adsorber while the first changes to regeneration mode. The wet compressed air now passes through the fresh regenerated adsorber tower thus setting up a continuous process.