PSA Oxygen Principles
The principles of Pressure Swing Adsorption (PSA) oxygen generator are adsorption and desorption. Each gas has a characteristic adsorption rate that when adsorbed by Zeolite Molecular Sieve (ZMS). ZMS has large surface area containing volumes of micro pores and passageways. Nitrogen has a higher adsorption rate than oxygen. When compressed air enters ZMS, oxygen molecules are able to pass through this large surface, and nitrogen molecules are adsorbed to the surface area. Adsorption and diffusion are the general principles of the PSA system since each gas has a characteristic adsorption rate that is a function of its ability to be adsorbed by a molecular sieve. The adsorption process can produce a range of gas with purities more than 90% oxygen.
As the ZMS is saturated with nitrogen, it should be depressurized to regenerate for next cycle. We use two adsorption vessels filled with ZMS to produce a continuous stream of oxygen.
During depressurization, the oxygen of lower purity than required is transferred to another vessel first, which is called
pressure equalization (for detailed information please check Chapter 4.2. Pressure equalization donates to higher
efficiency and less energy consumption).
PSA Oxygen System Equipments Description
The PSA system of normal purity (93±3%) is consisted of equipment as followings, according to the different user’s
requirements, it may be different.
For some small flow rate PSA oxygen generator,for example 5Nm3/h with CAN GAS model CAPO-5,it can be made in skid mounted as below photo show.
