PTA（精对苯二甲酸）行业生产过程中产生大量150℃精制母液废水，废水中携带大量高附加值成分和大量废热。创新性地提出应用多级闪蒸塔结合第二类吸收式热泵技术进行PTA精制母液余热回收，有效回收热量制备压力0.20~0.27 MPa、温度120~130℃的蒸汽，并降低母液温度到40℃。利用低温结晶技术回收高附加值成分TA固体及PT酸，回收率分别为92.0%、92.2%。废水达到后续处理要求，处理后的PTA母液进入到后续的膜处理系统。

A plenty of 150℃ mother liquor wastewater generated in the production process of PTA (refined terephthalic acid) contains considerable high value-added components and carries a lot of heat.In this paper,the multi-stage flash tower combined with the second type absorption heat pump technology is innovatively used to recover waste heat carried by mother liquor of PTA refining unit,which effectively produces steam with a pressure of 0.20-0.27 MPa and a temperature of 120-130℃ and reduce the mother liquor temperature to 40℃.The high value-added solid terephthalic acid and p-methylbenzoic acid (PT acid) can be recovered from mother liquor by the low temperature crystallization technology,with a recovery rate of 92% and 92.2% respectively.The remaining wastewater meets the requirements of subsequent processing,and then enters the subsequent membrane treatment system.