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 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
1000C. At this temperature regeneration is complete (due to dry air purge). Dew point achieved is around (-)
400 C. If still lower Dew point is required, air purging rate is slightly increased to 5% for (-)
600 C and to 7.5% for (-) 800 C Dew point.
