半导体厂含氟废水处理工程改造

Reconstruction of Fluoride-containing Wastewater Treatment Project in Semiconductor Plant

半导体生产废水中氟化物浓度较高,原有除氟工艺为二级加药[石灰、Al2(SO4)3]、二级沉淀,但出水氟化物不能达标。现将工艺调整为原水与石灰反应后即直接与Al2(SO4)3反应,再沉淀,同时改善反应条件。在基本不增加总投药量的情况下,出水氟化物浓度可稳定控制在8.0mg/L左右,达到了广东省《水污染物排放限值》(DB 44/26—2001)的一级标准。

The semiconductor wastewater contains fluoride with higher concentration. The original process of fluoride removal was two-step adding lime and A1 （SO）3 and two-step sedimentation. But the effluent fluoride could not reach the required discharge standards. The process was adjusted to mixing the raw water with A12（SO）3 directly after the reaction with lime, then precipitation and improving the reaction conditions. Without increasing the total chemicals dosage, the effluent fluoride concentration can be continuously controlled at around 8.0 mg/L, and achieve the first class criteria specified in the Guangdong Province local standard Discharge Limits of Water Pollutants （ DB 44/26 -2001 ）.