The process of freezing air to filter out only oxygen
5-step flow of Cryogenic Air Separation
1
Air compression
Sucking in the atmosphere and compressing it to several tens of atmospheres
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2
Removal of impurities
Removal of moisture and carbon dioxide (components that freeze at low temperatures)
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3
Counter-current heat exchange cooling
Cooling compressed air to cryogenic temperatures by exchanging heat with cold exhaust gas
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4
Double column rectification
Repeated separation of liquid air using the 13-degree difference in boiling points
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Nitrogen (N₂)
Boiling point −196°C
Vaporizes first, moves to the top
78%
Liquid oxygen (O₂)
Boiling point −183°C
Remains as liquid at the bottom
21%