AIR SEPARATION PROCESS FOR THE PRODUCTION OF OXYGEN-RICH AND NITROGEN-RICH PRODUCTS

摘要

The present invention is an improvement to a two distillation column cryogenic air separation process which produces nitrogen-rich and oxygen-rich products. The improvement to the process is condensing at least a portion of the nitrogen overhead from the high pressure column in a reboiler/condenser against a crude liquid oxygen stream and in an intermediate reboiler/condenser located in the low pressure column against internal low pressure column streams. The condensed nitrogen overhead is fed either to the low pressure or high pressure columns as reflux. The vaporized portion of the crude liquid oxygen stream is work expanded to provide some or all of the refrigeration required for the process.