SYSTEM AND METHOD FOR REDUCTION OF WATER CONSUMPTION IN PURIFIED TEREPHTHALIC ACID PRODUCTION

摘要

An apparatus and method for the recovery of acetic acid, azeotropic agent, extraction agent, re-usable water and other reaction products such as p-toluic acid, from an aqueous stream generated during a terephthalic acid production process, having superior energy efficiency and reduced water consumption. The apparatus includes: an azeotropic distillation column to remove water from acetic acid, a pair of mother liquor extraction columns sequentially connected in series for primary recovery of extraction solvent and other organics, an azeotropic agent stripper for recovery of azeotropic agent and a post-separation solvent stripper distillation column for further separation of the aqueous bottoms stream from said extraction columns into a volatiles stream comprising mainly organics with a very low amount of water and a liquid stream comprising water containing very low amounts of organics, each stream being sufficiently pure that it can be recycled for reuse in the purification of crude terephthalic acid.