Control method to maximize argon recovery from cryogenic air separation units.

摘要

The present invention relates to an improvement to a conventional cryogenic air separation process having an argon sidearm column. The improvement to the process comprises reducing the pressure of the feed gas to the argon sidearm column across a control valve (302) and operating the argon sidearm column (303) at the lowest possible pressure consistent with a minimum temperature difference across the overhead condenser (309) and the unrestricted return (by 319) of crude oxygen vapor from the overhead condenser to the low pressure column.