Based on the method of adsorbent regeneration, these dryers are primarily classified into two types: heatless (or "mild-heat") regenerative dryers and heated regenerative dryers. Since heatless/mild-heat regenerative dryers operate via isothermal adsorption, they are also known as "Pressure Swing Adsorption" (PSA) dryers; conversely, heated regenerative dryers operate via isobaric adsorption and are known as "Temperature Swing Adsorption" (TSA) dryers.
In practical application, there is also a type known as the "mild-heat" (or "low-heat") regenerative dryer. Although these dryers appear to heat the regeneration gas, the gas used for regeneration is actually dry air-with very low moisture content-sourced from the unit itself; consequently, they are classified as "Pressure Swing Adsorption" dryers.
