Regenerative Air Dryers
Industrial Air Dryers > Regenerative Air Dryers
Regenerative air dryers were designed to provide a continuous supply of compressed air at low Pressure Dew Points. Pressure Dew Point refers to the temperature that your compressed air distribution system (the piping that moves the compressed air from it point of creation to its point of use) must be exposed to BEFORE the trapped water vapor it contains condenses out and returns to its liquid form.
Regenerative air dryers consist of two towers (pressure vessels) filled with desiccant. As the air passes through these beds of desiccant, water vapor attaches to the surface of the desiccant through a process called adsorption. The dry air then exits the dryer and enters your system.
During the process described above, one of the two towers is on-line and drying the air while the other is off-line being regenerated. These towers alternate so that the air stream is always exposed to dry desiccant.
There are several methods of regeneration:
Pressure-Swing (Heatless) Regeneration – A portion of the dried compressed air is expanded to near atmospheric pressure and allowed to purge through the regenerating tower. This low pressure, extremely dry air pulls water from the desiccant and carries it out of the dryer.
Internally Heated Regeneration – Heating elements are installed within the towers containing the desiccant. These heaters warm the desiccant while purge air circulates the heat and carries off the water vapor. This method uses less of your system air as purge air, but requires additional electricity to power the heaters.
Externally Heated Regeneration – External heaters mounted on the dryer heat purge air (either dried compressed air or atmospheric air). This purge air carries that heat to the desiccant and removes the water vapor.