
1) Gas technology 2) Industrial process 3) Thermodynamic process
Found on
https://www.crosswordclues.com/clue/air-separation

An air separation plant separates atmospheric air into its primary components, typically nitrogen and oxygen, and sometimes also argon and other rare inert gases. The most common method for air separation is cryogenic distillation. Cryogenic air separation units (ASUs) are built to provide nitrogen or oxygen and often co-produce argon. Other metho...
Found on
http://en.wikipedia.org/wiki/Air_separation
No exact match found.