METAL MEMBRANE FILTERING METHOD IN TEREPHTHALIC ACID PRODUCING PROCESS INCLUDING FILTERING STEP, RECYCLE STEP, AND WASHING STEP

摘要

PURPOSE: A metal membrane filtering method in a terephthalic acid producing process is provided to minimize the used amount of raw material by recycling acetic acid passing through a filter as a raw material.;CONSTITUTION: A metal membrane filtering method(400) in a terephthalic acid producing process includes the following steps of: discharging the filtered liquid after injecting mother liquor in a side of a metal membrane filter(410); determining pressure difference between a mother liquid injection part and a filtered liquid discharge part of the filter part(420); stopping a filtering step by closing a first and a second valves if the pressure difference is bigger than the predetermined pressure value(430); recycling the discharged acetic acid after injecting the acetic in the other side of the metal membrane filter(440); and washing the filter part(470).;COPYRIGHT KIPO 2010