Technology

Pressure Swing Adsorbtion (PSA) is the most commonly used non-cryogenic oxygen production process; It is the most effective production method for small to medium capacities. The process works by using two columns filled with an adsorbent material, a molecular sieve called Zeolite. Pre-treated compressed air enters the first column and flows up through the Zeolite. Nitrogen and other trace gases are trapped in the Zeolite, whilst oxygen flows through unimpeded. When the Zeolite in the active column is saturated with nitrogen, the air flow is re-directed to the second column. The first column then depressurizes. Nitrogen is purged out of the Zeolite to the atmosphere, allowing the Zeolite to completely regenerate, waiting for the second column to become fully staturated. The process is repeated continuously; when one column is pressurizing, the other regenerates/de-pressurizes and at the end of each cycle they switch roles. This allows the generator to produce a constant flow of purified oxygen.