Heat reactivated type air dryers are used when one needs compressed air of very low dew point of(-)60 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 point Drying unit has Two-vessels filled with desiccant activated alumina or molecular sieves. One vessel remains in drying cycle for 6 hours ,while other vessel is simultaneously regenerated at atmospheric pressure Around 5% flow of dryer capacity is used aspurge for regeneration .Electrical heaters are provided in a central finned stainless steel pipe in both drying vessels . Heating cycle is for two hours, in this time hot purge air increases desiccant temperature to around 120 .At this temperature regeneration is complete (due to dry air purge) and dew point achieved is around (-) 40 Deg C .Still if lower dew point is required ,air purging rate is slightly increased to 7% for (-) 60 and to 8.5% for (-)80 dew point. Radiant Engineering gas filters a pre-filter with automatic drain valve is provided to remove any physical moisture from compressed air before entering into air dryer. A Micronics filter is also provided inthe dryer outlet to arrest any desiccant dust particles, up to 1micr size
Salient features
Longer life of operation
Requires less attention of operator
Once installed can be operated automatically
Heaters and valves are operated automatically
Internal heaters provide maximum efficiency resulting in lower power requirement