A pressure swing adsorption oxygen or nitrogen generator, or PSA generator, uses adsorptive materials to separate nitrogen or oxygen from other gasses for use. They're among the most popular gas generators because they deliver very pure gas and are both cost- and eco-friendly.Nitrogen generators extract nitrogen in the ambient air through a Pressure Swing Adsorption (PSA) process. Compressed and clean air passes through a molecular sieve bed, allowing the nitrogen to pass through and be captured as a product.
Adsorption is a process in which molecules of a liquid or gas are bound by physical or chemical means to the surface of a solid. Adsorptive materials such as activated carbon are composed of small beads with many tiny micropores inside to maximize the available surfaces that molecules can adsorb to. An adsorption nitrogen generator works by adsorbing oxygen and carbon dioxide gas and moisture from the air, leaving purified N2 gas. The most common adsorptive material is Carbon Molecular Sieve, tiny beads of carbon with thousands of microscopic pores.
PSA nitrogen generators work using the basic principles of adsorption. The name comes from the way they use pressure swings to increase adsorption during the separation phase and then recharge the adsorbent material. A dual-chamber PSA enables continual nitrogen generation, with one chamber producing N2 while the other chamber recharges.
The rate of adsorption increases when the chamber is pressurized. Purified nitrogen gas is separated out of the chamber and stored when it reaches the desired level of purity.
When the chamber is depressurized, excess oxygen and other gases trapped within the CMS pores are released, recharging the beads for the next cycle of pressurization and adsorption.
Each chamber swings between a high-pressure nitrogen generation phase and a low-pressure regeneration phase, enabling continuous production of nitrogen gas.