Gas separation membranes are very fine hollow fibers through which different mixtures of gases are fed. As the gases travel through the tubes, a process called selective permeation allows us to separate gases.

At a closer look, gas separation membrane, the wall of each of these micro-thin hollow fibers, is an asymmetric filter made of various types of polymer. As different gases travel through the fiber, they come into contact with the membrane and permeate through it.

The permeation rate of each gas is determined by its solubility in the membrane material and its diffusion rate. Gases with higher solubility and smaller molecules (fast gases) can pass through the membrane faster than other less soluble gases with generally larger molecules (slow gases).

Gases which permeate faster and more are collected outside of the hollow fiber as permeates while gases which do not permeate so well and stay inside of the fiber until they reach the other end are separated out as retentates.Depending on the properties of the desired gas, either or both of permeates and retentates can be used.

The permeation rates of different gases and vapors also vary according to the types of polymers used to make membrane fibers. Carefully controlling the material of membrane varies the sorption-diffusion mechanism through the membrane which determines the permeation rate through it.

For instance, if we want to separate methane from carbon dioxide for biogas upgrading, we would feed biogas through the membrane filter. Since carbon dioxide (CO 2 ) permeates through the membrane much faster than the heavier methane (CH 4 ), we get carbon dioxide ‘filtered’ out of the membrane fiber as permeate and methane staying inside the hollow fiber as retentate; methane is then collected at the end of the membrane filter.

Environmental Benefits

● Separation at room temperature: low energy consumption

● No phase change

● No environmental emissions (no waste water or absorbent)

● No additional supply materials required: no secondary pollution

Improved Safety

● No risks associated with handling gas cylinders

● No chemicals required

Nitrogen Generation

Nitrogen is the most widely used gas in industries; its versatile application ranges from blanketing and inerting to explosion protection. On-Board Inert Gas Generation System (OBIGGS) protects fuel tanks on aircrafts and ships from the risk of fuel vapor explosion by replacing with nitrogen.

● Fuel tank inerting : OBIGGS

● Shipboard inerting (FPSO, FLNG, LNG Carrier)

● Chemical processing

● Iron/aluminum/copper production and metals processing

● Tire inflation

Power

Power generation requires a reliable and cost-effective solution for the control of various gases. Gas membrane is a perfect answer for many of those challenges; improving fuel efficiency with oxygen-enriched air, ensuring safety through inerting and purging systems, or reducing carbon emission.

● CO ₂ Capture & Storage

● O ₂ generation for oxyfuel combustion

● H ₂ purification for fuel cell power generation

● Inerting system

● Oxygen removal from steam water

Microelectronics

Semiconductors and display panels manufacturing requires high-purity gas control. Even waste water containing IPA or SF 6 can be treated with gas membrane to produce more concentrated IPA/SF 6 solutions which can be recycled and generate additional revenue.

● IPA/Hydrochloric acid purification for recycling

● Oxygen/Carbon dioxide/Nitrogen controlling for de-ionized (DI) water

● Anti-static treatment for ultrapure water

● Clean room for ultra-fine dust removal

Food & Beverage

Long-distance transportation and prolonged shelf life requirements have made nitrogen an essential part of the food and beverage industry. AIRRANE is also working to provide solutions which control a variety of gases to revolutionize the taste of our everyday drinks.

● Modified atmosphere packaging (MAP)

● Storage tank blanketing and water treatment

● Controlled atmosphere transport and storage

● Carbonation for Bag-in-Box Bee

● Nitrogen coffee/beer

● Sparkling wine

Health Care & Air Quality Control

From humidity control and oxygen generation systems at hospitals to air purifier and oxygen generator at home, an increasing demand for air quality control will be met with gas membranes.

● Air dryer and air purifier

● Humidity controller

● Portable oxygen concentrator

Natural Gas

● Nitrogen, CO 2 , H 2 S removal

● Enhanced oil/natural gas recovery

● Offshore nitrogen generation

Refinery

● Hydrogen recovery from syngas processes

● CO 2 removal from syngas

● Steam generation with enriched oxygen air

Petrochemical

● Hydrogen purification

● Recovery of monomer & solvent from EO, PE, PVC process