Ideal for industries such as electronics, pharmaceutical, food preparation, pneumatic conveying, automotive paint finishing or for installations with outdoor pipe work, a pressure dew point of +3C from a refrigerant dryer is insufficient. For these applications, a HDT heatless adsorption dryer is required supplying compressed air at a pressure dew point of -20C, -40C or -70C.

The HDT heatless adsorption dryers consist of two parallel vessels lled with adsorption material (molecular sieve). While compressed air is dried in one tower, the second saturated tower, having just come off the line, is regenerated. A small amount of dried compressed air is used for this purpose.