A rotating desiccant wheel allows approximately 3/4 of the wheel to be used for inlet air and absorb the moisture while the remaining portion goes through a process to regenerate and dry.
During regeneration, the desiccant is heated by a direct-fired gas burner or indirect-fired water or steam coil. The wheel continues to rotate and the adsorbent process is repeated. Air dried through this process may be outside air, inside air, or more commonly, a mixture of air with high humidity content. After passing through the desiccant wheel and being dried, the air is called process air and can be cooled and/or filtered. Hot air and moisture removed from the desiccant is exhausted outside or passed through an air-to-air heat exchanger. Using a heat exchanger to preheat incoming process air can offer substantial savings in northern climates.
Desiccant wheels are often installed in:
- retail facilities
- office buildings
- clean rooms
- industrial sites
- other dehumidification applications where corrosion protection, condensation control and mold and mildew control are needed