Process for the low temperature decomposition of air comprises feeding a first process air stream into a high pressure column, producing a first oxygen-enriched fraction in the high pressure column, and further processing

摘要

Process for the low temperature decomposition of air comprises feeding a first process air stream (6, 10, 16) into a high pressure column (1); producing a first oxygen-enriched fraction (53, 54) in the high pressure column; feeding the first oxygen-enriched into a middle pressure column (2); and feeding a second oxygen-enriched fraction into a low pressure column (3). The method further comprises withdrawing a first oxygen stream (71, 81) as a liquid from the low pressure column or from the middle pressure column; and withdrawing a nitrogen stream (41) from the three column system (1, 2, 3), compressing and using as a heat carrier stream to vaporize and/or heat the liquid oxygen stream and returning to the three column system. Preferred Features: Gaseous nitrogen from the high pressure column is condensed in a first main condenser (4) by indirect heat exchange with an oxygen-rich fraction from the middle pressure column.