METHOD Russian patent published in 2019 - IPC C07C51/44 C07C53/08 C07C51/12 C07C53/122 

FIELD: chemistry.

SUBSTANCE: invention describes a method of operating a heavy fraction separation column at an industrial plant for producing acetic acid, said industrial plant comprising at least a reaction section, a light fraction recovery section comprising a light fraction separation distillation column, and a heavy fraction separation column, wherein a stream comprising acetic acid and propionic acid obtained from the light fraction recovery section is fed into the heavy fraction separation column through an inlet located in the intermediate portion of the heavy fraction separation column, and product stream, mainly acetic acid, is removed from column for separation of heavy fractions through outlet for side product located above inlet, and product stream comprising propionic acid, is removed from the column of separation of heavy fractions through the outlet hole for heavy products, located below the inlet opening, wherein the column for separation of heavy fractions is operated in conditions, at which in the separation column of heavy fractions above the inlet opening there is created lower pressure compared to pressure of the stream containing acetic acid and propionic acid, which is supplied to the column of separation of heavy fractions, and wherein the pressure at the outlet of the heavy fraction separation column is less than 1.0 bar abs, the number of theoretical separation stages between the inlet and outlet for the side product is at least 5, preferably at least 7, more preferably at least 10, and pressure drop in part of separation column of heavy fractions between inlet opening and outlet opening for product of side line is not more than 10 mbar in terms of theoretical separation stage.

EFFECT: present invention provides a method of operating a heavy ends column in an acetic acid production unit.

29 cl, 2 dwg, 3 tbl, 1 ex