Cryogenic process for producing low-purity oxygen

摘要

This invention relates to an improved cryogenic separation process employing a single pressure distillation column for the recovery of low purity, high pressure oxygen. The process uses two working fluids, i.e., high pressure air and high pressure nitrogen to effect reboil in the column. Both the condensed air and nitrogen streams are fed as reflux streams to the distillation column. The use of nitrogen reflux enhances oxygen recovery by enhancing purity of the nitrogen from the column.