SEPARATION RECTIFYING APPARATUS FOR MIXED GAS

摘要

PROBLEM TO BE SOLVED: To make a cold box compact and reduce idle space within it by arranging top parts of two towers among a plurality of columns at a same height and providing at least two towers among a plurality of the columns with a same vertical size. SOLUTION: For example, a separation rectifying apparatus for nitrogen and oxygen has a two-tower column 1 comprising a first rectifying part and a second rectifying part in a cold box 9, and the second rectifying part comprises two sections of a section 3A and a section 3B. Tower top parts of the section 3A and the section 3B of the second rectifying part are arranged at a same height. A gas is supplied from the first section 3A to a tower bottom part of the second section 3B of the second rectifying part and a gas from a tower bottom part of the second section 3B is supplied to the tower top part of the first section 3A. Vertical size of the second section 3B of the second rectifying part is equal to a vertical dimension obtained by combining the first section 3A of the second rectifying part and a first rectifying part 2.