The process by which gaseous nitrogen is extracted from ambient air is based on the separative properties of the hollow fibre membrane modules. The relative dry and clean compressed air flows through the membrane fibres in which the air is separated into enriched nitrogen and an enriched oxygen flow.
The principle enabling this separation is the discrepancy in the permeation rate of various gases through the polymer membrane. Oxygen and water vapour permeate more rapidly than Nitrogen. The pressurised air is feed into the fibres and the permeate will go through the membranes. The membrane housing operated at atmospheric pressure and the permeate goes through and open connection to the atmosphere. The membrane housing therefore can not be pressurised and are no pressure parts. There are several membrane suppliers in the world and each type of membrane has its capability for a certain application (range of application.