Business & Products Industrial Gas Business

Gas Recycling Equipment

SF6 Recovery, Refining and Reutilization System

SF6 (Sulfuhexafluoride)-based gases are used as essential gas for etching and cleaning in the manufacturing process of semiconductors and liquid crystal devices.
Air Water has proposed “SF6 recovery, refining and reutilization system” with which SF6-based gases are separated and recovered by membrane separation and recycled for use with the refining purity of 99.95 to 99.999%.

Standard Specification

Target PFC Gases Sulfur Hexafluoride (SF6)
Recyclable Out Flow 100 ~ 1000 SLM (*high flow specification is also possible)
Refining PFC Gas Flow 1 ~ 10 SLM
Refining Purity 99.998 %(99.95 ~ 99.999 %)
Impurities N2≤16ppm , O2≤4ppm , H2O≤-80℃

Hydrogen Recovery and Refining System

As hydrogen is carbon-free energy, it has been attracting attention as fuel that can curb global warming. Hydrogen can be obtained by recovering and refining the reformed gas of exhaust gas from plants and of hydrocarbon.
Air Water's hydrogen recovery and refining system removes impurities in the target gas, such as carbon dioxide, carbon monoxide and hydrocarbon using adsorption agent and provides high-purity hydrogen with a purity of 99.99% or higher for reuse.


Flow Type 100 Nm³/h or less 200 Nm³/h 400 Nm³/h 500 Nm³/h or more
Purity 99.99% or more
Pressure 0.60 ~ 0.95 MPaG


  • Carrier process of semiconductors manufacturing
  • Synthetic process of chemical factory
  • Continuous annealing of iron foundry

Argon Recovery and Refining System

Argon, which is emitted during the silicon manufacturing process and others, contains impurities such as oxygen, nitrogen and hydrogen and is normally released in the atmosphere as it is without being reused.
With Air Water's argon recovery and refining system, reusable high-purity argon gas can be provided by increasing the pressure of the recovered waste argon by a compressor and removing gas impurities in a normal temperature refining unit and rectifier.


Composition O2 N2 H2 CO CO2 CH4 H2O Out flow Recovery rate
Gas < 0.5 ppm < 0.5ppm < 0.5 ppm < 0.5 ppm < 0.5 ppm < 1 ppm < 1 ppm 300 Nm³/h > 95 %


  • Lifter furnace of silicon single crystal
  • Ruhrstahl-Hausen furnace of iron and steel

Methane Recovery and Refining System

Much of natural gas generated during the use of biogas or generated from the ground is released as it is in the atmosphere.
Air Water's methane recovery and refining system recovers emitted natural gas and removes the contained impurities such as nitrogen so as to be able to supply methane gas that can be used as fuel.

Liquid Natural Gas BOG (boil-off gas) Nitrogen Removal Device

Natural gas generated from gas wells contains unburnable components such as nitrogen. There are concerns that high nitrogen concentration in the BOG (boil-off gas) from the liquefied and stored natural gas in LNG tanks may lower the methane recovery rate in the reliquefaction system.
Air Water's liquid natural gas BOG nitrogen removal device provides established technology to remove nitrogen in vaporized natural gas with high efficiency, which has been considered to be difficult, so as to recover, refine and reuse methane. Two processes have been proposed, one being an “adsorption-separation process” which removes nitrogen from methane using special activated carbon and the other being a “cryogenic distillation process.”


  • Methane recovery in a natural gas field