Based on concentration diffusion and following these two points:

(1) Pressure generates kinetic energy due to release.
Therefore, the higher the pressure of the compression system, the better the desorption and regeneration effect.
(2) The removal of moisture can only be completed by a carrier (CDA). The most economical way to use CDA is to make the completely dry air saturated at the exhaust end. Therefore, after saturated compressed air enters a heatless dryer, the compression ratio can be used to fully explain its operation and the theoretical limits of energy consumption.

The compression of air causes water vapor to become supersaturated. After the supersaturated liquid water is discharged, the heatless adsorption dryer adsorbs the water vapor in the saturated compressed air, and dry compressed air is sent from the dryer outlet to the application end. However, a specific proportion of the compressed dry air must be deducted (consumed) to complete the regeneration process.

Example: Under 100 PSIG and constant temperature, the compression ratio of dry compressed air = (100+14.7) ÷ 14.7 ≈ 7.8.
This can be interpreted as the relative humidity (water content ratio) of the air after compression being 12.82% (1 ÷ 7.8) of that at atmospheric pressure.
此水汽被吸附剂吸附后，若须脱附再生，则理论上至少须消耗 12.82％ 的 CDA 始可将水汽完全的排出。

Consider:
(1) Piping pressure drop
(2) Desorption endothermic reaction leads to temperature drop, reducing the moisture carrying capacity of the carrier.
(3) The moisture carried out by the carrier does not reach saturation.
(4) Process direction,
(5) Adsorption heat is not fully utilized,
(6), (7), (8), etc., unfavorable factors will only make the air consumption rate higher than the theoretical value, not lower.

※ Combinations with refrigerated dryers or vacuum regeneration, etc., are not within the scope of this discussion.