DEVICE AND METHOD FOR SEPARATING AIR BY CRYOGENIC DISTILLATION

摘要

The invention relates to a device for separating air by means of cryogenic distillation, said device comprising a medium-pressure column (1) and a low-pressure column (2) but no argon production column, said low-pressure column comprising at least four distillation segments (24, 25, 26, 27, 28) of which at least a first intermediate distillation segment (25) of the low-pressure column is surrounded by an auxiliary shell around which a space is defined that is divided into a lower section and an upper section along the radius of the column, said intermediate segment(s) being located in the intermediate part of the low-pressure column, the capacity of the first intermediate segment being greater than that of at least one adjacent segment (24, 26).