Gas purification by membranes

In gas purification, membranes are used to separate components in natural gas such as water, CO2 and hydrocarbons according to their permeabilities. Each gas component entering the membrane unit has a characteristic permeation rate that is a function of its ability to dissolve in and diffuse through the membrane.

The driving force for separation of a gas component in a mixture is the difference between its partial pressure across the membrane. As high pressure feed gas flows into the metal shell of the membrane unit, the fast components, such as water and CO2, permeate through the membrane.

This permeate stream is collected at a reduced pressure, while the retentate, i.e., the dry natural gas, leaves the separator at a slightly lower pressure than the feed.

Pietro Fiorentini offers this technology both in natural gas and in biogas purification applications.