The Heat of Compression type dryer is designed to take advantage of the natural tendency to dessicant to established equilibrium with their surrounding and can deliver super dry compressed air. These type of dryers are the most economical and dew points up to (-)60 °c are easily achieved. Such dryers are mostly preferred for flow up to 6000 cfm.


  • Having least running cost
  • Best quality of air
  • Lesser payback period
  • Continuous duty with long efficient service life
  • Easy to install and user friendly

Process Description

The Heat of Compression (HOC) dryers are No-Purge Loss type desiccant dryers based on adsorption principle. The hot air from the Compressor at min 120 deg C and higher temp, is used directly for regeneration of the desiccant. After regeneration, this air is cooled down to 40 deg C and then it is dried in second tower. Thus, the use of heaters is eliminated. For eg. in the 6+6 Hrs. Cycle the hot air is fed for regeneration for 4 Hrs. and for balance 2 Hr. a changeover takes place where the air is first cooled in cooler, then dried and before going to the outlet, cools the regenerated desiccant bed, thus bringing it down to ambient temperature. This cycle is reversed for the next 4Hrs. where the Adsorber drying the air in the previous cycle goes for regeneration and vice versa.

It’s having least running cost with best quality of air.

A typical representation for the plant is shown in the figure below:

FIGURE: HOC Type Air Dryer


  • Synthetic Fiber Industry
  • Chemical Process Industry
  • Air Curtains
  • Other Miscl. Industrial Applications


Product Air Dryer
Plant Capacity 750 CFM to 6000 CFM
Product Specifications Dew Point: -40 to -60°C ADP
Purge Loss: NIL