用铸钢废水处理含氟废水的研究

RESEARCH ON TREATMENT OF FLUORIDE-CONTAINING WASTEWATER WITH THE WASTEWATER AFTER CASTING STEEL

用大连机车厂的铸钢废水辅以氯化钙、膏状硼泥复合混凝剂作为除氟剂，通过化学络合、沉淀、吸附、絮凝等效应处理含氟废水。若处理１００ｍｇ／Ｌ左右含氟废水，所用药剂之最佳用量分别为：铸钢废水７．５％，氯化钙１．５‰，膏状硼泥复合混凝剂２．５‰，最佳除氟ｐＨ值为６．３－８．０。沉降２ｈ，除氟率可达９４．５％，沉渣体积占原水体积１０％，符合排放标准。处理费用低。

The fluoride-containing wastewater was treated by casting steel wastewater drained from Dalian Locomotive Plant with calicium chloride and boron sludge compound coagulant(pastc) as fluoride removal agent through the effects of removing fluoride such as: complexation、deposition、adsorption、coagulation. If treating the wastewater with about 100mg/L of fluoride, the most proper dosage for removing fluoride is as follows: the casting steel wastewater, 7.5%; calcium chloride, 0.15%; Complex coagulation of paste-status boron sluge, 2.5%; optimum pH value for removing fluoride, 6.3-8.0. When sedimenting for 2h, the fluoride removal rate can reach to 94.5%; the volume of sedimenting dregs accounts for 10% of raw water volume, meeting the discharge standards. The treating method possesses the advantages of low cost and simple operation.