OXYGEN - PRESSURE SWING ADSORPTION

Oxygen needs to be produced in large volumes for many applications. Perhaps the commonest of these are in medicine and in the pulp and paper industry. There are two methods used for doing this: cryogenic and pressure swing adsorption. Pressure swing adsorption, which is outlined in this article, is most useful for small applications such as oxygen production in the home for asthma sufferers. Pressure swing adsorption relies on air being filtered through aluminosilicate minerals known as zeolites. The one used for PSA oxygen has been specially designed so that nitrogen gas is adsorbed onto it while oxygen (and argon) pass straight through. The zeolite is quickly saturated with nitrogen, so two zeolite beds are usually used together, one filtering air while the other is regenerated. This process is very environmentally friendly and the technique is also potentially able to be used to remove other gases (such as CO2) from industrial waste gas streams.