PSA technology nitrogen generators
“Pressure Swing Adsorption” (PSA) Generators.
Nitrogen is produced by piping compressed air through special molecular sieves (CMS), which are able to retain O2 , H2O, CO2. The purity of produced nitrogen can vary from 95 to 99.999%.
The new NIMOS generators can be seen as an evolution of traditional systems which use the PSA principle (Pressure Swing Adsorption) allowing a constant production of Nitrogen from compressed air. NIMOS generators are made of two or more modules featuring two columns. Each one is filled with high quality molecular sieves, characterized by a high porosity and, as a consequence, by an excellent selectivity.
The compressed air, which has been dried and filtered, will pass through one of the two columns and cede oxygen, other gasses and water vapour. After few seconds, before the sieves got completely saturated, the column will be depressurised in order to release the oxygen into the atmosphere.
At the same time, compressed air will be deflected to the other column, yielding oxygen until the next change.
The cycle, which is uninterrupted until the tank is filled up, ensures a constant nitrogen flow. As soon as the tank reaches its maximum filling pressure, the generator, automatically places itself on standby mode – waiting for a new gas demand.
Oxygen molecules are very small (0,28 mm), and often remain trapped in the cavities characterising the surface of molecular sieves. Nitrogen molecules instead, are larger (0,32 mm), and are not captured by the sieve’s porosity.