Adsorption dryers achieve drying through "pressure change" (based on the pressure swing adsorption principle).
Since the air's capacity to hold water vapor is inversely proportional to pressure, a portion of the dried air (known as regeneration air) is depressurized and expanded to atmospheric pressure. This pressure change renders the expanded air even drier; this air is then directed through the desiccant bed requiring regeneration (i.e., the tower that has already absorbed significant moisture). The dry regeneration air extracts moisture from the desiccant and carries it out of the dryer, thereby achieving dehumidification. The two towers operate cyclically without the need for an external heat source, continuously supplying dry compressed air to the user's system.
