Patent ID: 7090748

Claim:
A dividing wall column having a dividing wall which is essentially disposed along the long direction of the column, which divides the column interior into a feed part, a take off part, an upper shared column part and a lower shared column part, with feed in whole or in part in the vaporous state of a mixture to be separated between the upper region of the feed part and the lower region of the feed part and/or side stream take off in whole or in part in the vaporous state between the upper region of the take off part and the lower region of the take off part, in which, when the feed is in whole or in part in the vaporous state the cross-sectional area of the upper region of the feed part is increased by plane-parallel displacement of the dividing wall toward the upper region of the take off part and/or the side stream take off is in whole or in part in the vaporous state, the cross-sectional area of the lower region of the take off part is increased by displacement of the dividing wall toward the lower region of the feed part, in such a manner that the F factor is substantially the same in all column regions wherein the ratio of the cross-sectional areas of the upper region of the take off part to the upper region of the feed part is from 1:1.6 to 1:2.4, and/or the ratio of the cross-sectional area of the lower region of the take off part to the lower region of the feed part is from 1.6:1 to 2.4:1.