半导体行业含氟废水处理探讨
2019-08-06杨晓春王华丽周丽兵
杨晓春 王华丽 周丽兵



摘要:目前,上海市执行的《半导体行业污染物排放标准》(DB31/445-2006)中氟化物排放限值为20mg/L,虽然即将实施的《电子工业污染物排放标准》二次征求意见稿中氟化物间接排放限值没有变化,但北京市现行的《水污染物综合排放标准》(DB11/307-2013)表3中规定,排入公共污水处理系统的氟化物限值仅为10mg/L。对于整个半导体行业来说,氟化物的排放限值要求有日益严格的趋势。出于对排放标准的前瞻性考虑,为应对日益严格的污染物排放要求,某半导体公司对既有的含氟废水混凝-沉淀处理工艺做出了一系列改进,包括改变CaCl2投加量、改变水力停留时间、电絮凝、投加除氟剂等,形成半导体行业含氟废水处理最佳可行技术。这对指导上海乃至全国半导体行业含氟废水的达标排放具有重要意义。
关键词:含氟废水;混凝-沉淀;CaCl2投加量;水力停留时间;电絮凝;除氟剂
中图分类号:X703 文献标识码:A 文章编号:2095-672X(2019)06-00-03
DOI:10.16647/j.cnki.cn15-1369/X.2019.06.016
Abstract: The fluoride limit in The discharge standards of pollutants for semiconductor industry (DB31/445-2006), the present discharge standards of Shanghai is 20 mg/L,which is similar to the fluoride limit in Emission standard of pollutants for electrical industry that will be implemented in China. Nevertheless, the limit value of floride in Integrated discharge standard of water pollutants of Beijing is 10 mg/L. Therefore, the situation shows that the fluoride limit has an increasingly stringent trend. A semiconductor industry has made a series of attempts based on its floride treatment technology, including the change of CaCl2 dosage, the change of hydraulic retention time (HRT), electrocoagulation, the use of defluorinating agents, etc. This study describes the research that the author has been done, and discusses the Best Available Technology (BAT) of fluoride-containing wastewater treatment for semiconductor industry.
Key words: Fluoride-containing wastewater; Coagulation-precipitation;CaCl2 dosage; Hydraulic retention time (HRT); Electrocoagulation; defluorinating agents
近年來,随着半导体行业在国内的迅速发展,一系列不容忽视的环境问题相继出现。其中,含氟废水的超标排放可能造成地表水体、土壤、地下水的污染,人体摄入过量的氟可能导致急性中毒,高浓度的氟污染可刺激皮肤及粘膜,引起皮肤灼伤、皮炎、呼吸道炎症等,严重可引起肺水肿、肺出血,喉及支气管痉挛甚至皮肤灼伤、溃疡和坏死。低浓度的氟污染对人畜危害主要为牙齿和骨骼的氟中毒。牙齿氟中毒主要表现为牙齿着色、发黄、牙质松脆、缺损等。……
