How Oxygen PSA Technique Works?
Pressure swing adsorption (PSA) oxygen production is a gas separation technology based on the principle of physical adsorption. It purifies oxygen from the air through the selective adsorption of molecular sieves.
The Basic Principle Of PSA Oxygen Production
- PSA oxygen production utilizes the difference in the adsorption performance of nitrogen and oxygen (in the air) on the molecular sieve, as well as the characteristic that the adsorption capacity changes with the pressure.
- Under equilibrium conditions, the molecular sieve preferentially adsorbs the nitrogen component. Under increased pressure conditions, the adsorption of nitrogen is higher than the adsorption capacity at low pressure.
- And the desorption regeneration of the molecular sieve is achieved by changing the operating pressure, that is, pressurized adsorption and decompression desorption, thereby achieving oxygen and nitrogen separation.
Zeolite Molecular Sieve In Oxygen Production System
- The core component of the oxygen production system is molecular sieve. Although oxygen and nitrogen are non-polar substances, they will produce induced dipoles under the influence of zeolite molecular sieves.
- There is an attraction (inductive force) between the induced dipole and the inherent dipole of polar molecules. Because the inductive force of nitrogen is greater than that of oxygen, the molecular sieve adsorbs much more nitrogen than oxygen.
- When the air passes through the zeolite molecular sieve, nitrogen is preferentially adsorbed by the molecular sieve and enriched in its micropores, while only a small amount of oxygen is adsorbed, and most of it passes through the molecular sieve to become product gas.
The Working Process Of PSA Oxygen Production
- The air is firstly compressed by a full-performance air compressor and passes through multiple filters to remove most of the particulate dust and impurities; then the hot air is cooled by a cold dryer to remove moisture from the air; and finally, it enters the air storage tank for buffering and pressure stabilization, and enters the adsorption tower that has been regenerated and is in working condition through a switching valve.
- In the adsorption tower, nitrogen, carbon dioxide and other gases are adsorbed by molecular sieves, and oxygen is enriched from the top of the adsorption tower and enters the oxygen buffer tank. On the outlet pipeline of the oxygen buffer tank, a sampling port is provided to detect the purity of oxygen. The qualified oxygen is then filtered through a dust filter and a sterilization filter to obtain qualified product-grade oxygen.
- In order to obtain continuous and stable product-grade oxygen, the PSA oxygen production equipment is equipped with at least two adsorption towers to produce oxygen alternately. When one tower adsorbs and produces oxygen, the other adsorption tower is in a regeneration state, and the other component gases discharged by regeneration process are silenced through a muffler and then released outdoors.
