Desiccant Heatless Type Dryers

How does it work
Regenerative desiccant dryers normally are of twin tower construction. One tower dries the
airtrom the compressor while the desiccant in the othertower is being regenerated afterthe
pressure in the tower has been reduced to atmospheric pressure. Regeneration can be
accomplished using a time cycle or on demand by measuring the temperature or humidity in
the desiccant towers or by measuring the dew point ofthe air leaving the on-line tower.
In the heatless regenerative desiccanttype, no internal or external heaters are used. Purge
air requirement can range up to 18% otthe total air-flow. The typical regenerative desiccant
dryer at 1000 psig has a pressure dew point rating of-40°F but dew points down to -100F can be obtained. Advantages of Regenerative Desiccant

Type Dryers include :

• Very tow dew points can be achieved without potentiai freeze-up.
• Moderate cost of operation forthe dew points achieved.
• Low maintenance costs.
• Heatless type can be designed to operate pneumaticallv for remote, mobile or hazardous locations.