The Dual Stage, High Purity Pressure Swing Adsorption (PSA) Oxygen Generating Process

Air contains 21% oxygen, 78% nitrogen, 0.9% argon, and 0.1% other gases. SUMER Dual Stage, High Purity Oxygen Generating Systems separate oxygen from compressed air utilizing a two stage Pressure Swing Adsorption (PSA) process to generate up to 99.5% pure oxygen.

Stage One:

The first stage of the PSA process uses molecular sieve (a synthetic zeolite), which attracts (adsorbs) nitrogen from air at high pressure and releases (desorbs) it at low pressure to generate up to 96% pure oxygen.

Stage Two:

The second stage of the high purity PSA process further purifies 95-96% oxygen to a level of up to 99.5% using a second type of molecular sieve (activated carbon sieve), which attracts (adsorbs) oxygen from the 95% oxygen stream at high pressure and releases it at low pressure.

The argon could be separated afterwards increasing the amount of oxygen up to 99%. Using a carbon molecular sieve (CMS) based adsorbent, which adsorbs the oxygen, allowing the impurities to be scrubbed. The maximum purity achievable in such systems is 99.5%. Typically, the system is operated at a design point of around 99.0% to optimize the output. In such a system there is about a 35% loss in the 95% feed product gas. This loss of product is sensitive to the purity level that is lower purity, less product loss. The whole process is intelligently controlled with help of automated valves and microprocessor.

In general Sumer Oxygen Generators produce 95% purity at around 75-80% of the generator's capacity. Then 35% of the produced oxygen is sacrificed for 99% purity. Therefore, primary oxygen generator has to have at least double the capacity of the desired 99% purity oxygen.