Process and apparatus for recovery of pure argon

摘要

The fractionation system has at least one air fractionation column (9) and an argon purification column (25). An argon-enriched mixture (24) of air gases, is introduced into the argon purification column (25). The top end product (28) of this column (25) is partially condensed by heat exchange (29) with a vapourised cooling medium (11). The condensate (28a) is sent back to the column as reflux; from the bottom of this column (25) a substantially nitrogen-free argon product (26) is withdrawn. An indirect heat exchanger (29) is used; the coolant (11) should have an oxygen content of less than 10%. Also claimed are a method involving the use of a heating medium, and two embodiments suitable to carry out the processes detailed.