SYSTEM AND METHOD FOR ACETIC ACID DEHYDRATION

摘要

A cost effective and energy efficient distillation technique for recovering acetic acid from a waste water stream containing acetic acid and water generated during terephthalic acid production employs a liquid-liquid extraction column and a downstream dehydration distillation column that operates under azeotropic or conventional distillation conditions to recover the acetic acid. The liquid-liquid extraction column produces an extract containing extraction solvent and acetic acid which is fed to the dehydration distillation column where the extraction solvent and acetic acid are separated. The dehydration distillation column can employ a condenser system for energy recovery. The condenser system can be a steam generator that condenses vapor into a concentrated acetic acid stream and generates low pressure steam. Any remaining acetic acid in the water is treated.