The drier bed is a pressure vessel charged with zeolite that has a high capacity for water.  As a gas stream containing water vapor passes through the bed, the zeolite adsorbs water molecules within the pores of the absorbent.  Dew points below -60˚C are routinely achievable with a regenerated bed. 

            The mass transfer zone of the drier is short by comparison to the bed length.  Once the bed is loaded and the mass transfer zone penetrates the bed exhaust, the dew point of the gas leaving rises gradually which provides sufficient warning to operators that the drier is exhausted.  Increasing the operating pressure improves capacity.

            Once at capacity, the drier bed can be heated to 350˚C to release the condensate from the bed into a purge gas stream.  After regeneration, the bed can be cooled to room temperature and returned to service as a drying medium.  The bed is robust and can withstand thousands of drying/regeneration cycles before any performance degradation is observed.

Design Benefits

            The drier Bed is designed for robustness.  The stainless steel welded vessel, rugged band heater, sheathed thermocouples, insulation and protective stainless-steel jacket ensure a clean package that can operate continuously at 350^oC without damage.

            The drier Bed comes standard with metal bellows isolation hand valves fitted with copper stem tips and VCR-8 female nuts.  The unit is helium leak tight to 1×10^-9 scc/sec at the operating temperature which is suitable for tritium service.