A new method for treating fluorine wastewater to reduce sludge andrunning costs

摘要

Reduction of the sludge generated in fluorine wastewater treatmentnis a critical problem for the semiconductor industry. We have developedna new method for treating fluorine wastewater in order to reduce sludgenand running costs. This method utilizes a small amount of Al(OH)3n not only as an aggregator for CaF2 generated fromnfluoride ions in the wastewater but also as an effective fluorinenadsorbent. The Al(OH)3 as fluorine adsorbent is usednrepeatedly through an AI(OH)3 reclamation process. This method canneffectively treat the concentrated fluorine wastewater to achieve annexceedingly low concentration in one-step treatment. We constructed anpractical treatment system using this method by modifying part of annexisting conventional system. This new treatment system is able tonreduce both the total sludge and running costs to about one-tenth thosenof a conventional system