Superheated Steam Regeneration of a Desiccant Wheel - Experimental Results and Comparison with Air Regeneration

A commercial zeolite desiccant wheel is tested with atmospheric pressure superheated steam regeneration over a range of air inlet conditions, steam inlet temperatures, and wheel rotation speeds. Results are compared with those from high-temperature air regeneration experiments on the same wheel obtained from the literature. For both cases the air stream to be dried was relatively hot and moist with inlet temperature and absolute humidity values of 50°C and 25 g · kg−1 chosen to reduce heat carryover. Using steam at 160°C to regenerate the wheel leads to the same dehumidification as using hot air at approximately 90°C. The benefit of superheated steam drying is that a nearly closed-loop regeneration process can be used with potential energy savings on the order of 30%.