Heat Reactivated Air Dryer

Heat Reactivated Air Dryer is used when one needs compressed air of very low dew point of (-) 60^o C or 80^oC. In Heat Reactivated Air Dryer, the desiccant is regenerated at higher temperature, along with small quantity of dry air purge. Due to purging with dry air and thermal regeneration, residual moisture loading on desiccant becomes low and this gives very low dew points.
Operating Principle
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 regenerates 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 degree c. At this temperature, regeneration is complete (due to dry air purge). Dew point achieved is around 40 degree c. If still lower dew point is required, air-purging rate is slightly increased to 5% for 60 degree C and to 7.5% for 80 degree C DEW point requirements.
   
Filters
A pre-filter with automatics drain valve is provided to remove any physical moisture from Compressed air before entering air Dryer. A  Micron filter is also provided in dryer outlet to arrest any desiccant dust particles, up to 1 micron size. Thus you get absolutely “Clean & dry compressed air.
Features

• A fully automatics unit requiring no attention of the operator
• Heaters switch ON/Off and all valves operate automatically
• Pressure is equalized to line pressure before changeover of drying vessels. This prevents pressure and flow surge and desiccant dusting.
• Low-pressure air requirement in compression to heatless type air dryer
• Desiccant life is around 5 year
• Internal heaters provided maximum heat transfer efficiency resulting in lower power requirements
• Counter current heated dry purge air provides maximum removal of moisture with minimum gas purge loss
• Heaters are not in physical contact with the desiccant resulting in long life or desiccant

Capacity

• Air Capacity : 5 to 5000 Nm³/Hr
• Dew Point : Up to (-) 40^o C to (-) 80^o C
• Operating Pressure :  5 to 35 Kg/cm²g