Internal Reactivated Type
The Drying unit has 2-vessels filled with Activated Alumina or Molecular sieves desiccant. One vessel remains in drying cycle for 4 hours, while other vessel is simultaneously regenerated at atmospheric pressure. Around 3% flow of dryer capacity is used as purge for regeneration. Electrical heaters are provided in a central finned Stainless steel pipe in both drying vessels. Heating cycle is for 2 hours and in this time hot purge air increases desiccant temperature to around 100˚C. At this temperature regeneration is complete (due to dry air purge). Dew point achieved is around (-)40˚C. If still lower Dew point is required, air purging rate is slightly increased to 5% for (-)60˚C and to 7.5% for (-)80˚C Dew point requirements.
A Pre-filter with automatic drain valve is provided to remove any physical moisture from compressed air before entering Air dryer. A micronic filter is also provided in the Dryer outlet to arrest any desiccant dust particles, up to 1 micron size. Thus, you get absolutely “Clean & dry compressed air”.
External Reactivated Type
In this design there is NO LOSS of compressed air. Time cycle is 6+6 hours with (-) drying towers filled with SILICA GEL desiccant. For regeneration, a centrifugal air blower and an electrical heater is provided. Desiccant is heated upto 200˚C by hot air for complete regeneration.