What is the difference between cryogenic oxygen and PSA?

 

Low-Temperature Oxygen and PSA (Pressure Swing Adsorption) are two common air separation technologies.

 

Low-temperature oxygen is used to separate oxygen and nitrogen in the air through low-temperature fractionation. The process exploits differences in the boiling points of air to separate gas components by cooling the air to a liquefied state and then gradually raising the temperature. Under low temperature conditions, oxygen in the air liquefies earlier, while nitrogen remains in a gaseous state. The liquid oxygen is then separated by distillation and collected.

 

 PSA uses the selective adsorption properties of adsorbents to separate oxygen and nitrogen. In the PSA oxygen generator process, air passes through a pressure swing adsorption tower composed of adsorbents. Adsorbents have different adsorption capacities for oxygen and nitrogen. During the adsorption stage, the adsorbent selectively adsorbs nitrogen while oxygen passes through. Then, during the pressure shift phase, the pressure is reduced so that the adsorbent releases the adsorbed nitrogen, making it available for adsorption sites again.

 

 Therefore, cryogenic oxygen and PSA are two different air separation processes. Low-temperature oxygen mainly relies on the boiling point difference of the gas, while PSA nitrogen generator uses the selective adsorption of the gas by the adsorbent to achieve separation. The choice of which process to use depends on the needs and technical requirements of the specific application.