The Membrane system uses hollow-fibre membranes to separate air into nitrogen and oxygen. The principle of separation is based on the selective permeation of different gases. The permeation speed is different for each type of gas. Nitrogen permeates slowly through the membrane, oxygen and water vapour quickly.

Compressed air fed into a bundle of membranes, leaves this bundle almost as pure nitrogen, the oxygen being vented.

Continuous monitoring ensures that the gas is of the correct purity. The membrane-type nitrogen generator is fully self-contained.

The normal Nitrogen purity ranges from 95% to 99.9%. A high level of purity requires a greater number of bundles, consumes more air and consequently a higher investment. Thus for maximum accuracy, accurate gas specifications are important.

Nitrogen Generators are mostly used on board of LNG carriers, FPSO/FSO’s, Product tankers and Chemical tankers. They can, however, also be found on board of Inland tankers and on certain Platform Supply vessels and other Marine applications.