铝电解固废处理过程中高盐高氟废水中氟的去除研究

Study on removal of fluorine from high-salt and high-fluorine wastewater in the solid waste treatment of aluminum reduction

本文采用化学沉淀-混凝沉淀的方法,利用石灰乳、氯化铝对铝电解大修渣湿法处理产生的高盐含氟废水进行除氟处理。研究结果表明,石灰沉淀法可有效去除高盐高氟废水中的氟,可使氟离子浓度降低至19.0 mg/L。AlCl 3·6H 2O的加入有利于高盐高氟废水中氟的去除,在n(Al/F)等于5.0时,上清液中氟离子浓度为2.7 mg/L,其作用的pH最佳值约为6.5~7.5。化学沉淀-混凝沉淀法对铝电解大修渣湿法处理后的高盐含氟废水中的杂质离子具有较好的协同处置效果,为高盐溶液的后续处理和高值化利用提供了更广阔的空间。

In this paper,the limemilk and aluminum chloride are used with the method of chemical precipitation and coagulation precipitation to remove fluorine from the high-salt and fluorine-containing wastewater produced by the wet treatment of aluminum spent lining.The results show that the method of lime precipitation can effectively remove fluorine from the high-salt and high-fluorine wastewater,as a result of which the concentration of fluorine ion can be reduced to 19.0 mg/L.The addition of AlCl 3·6H 2O is helpful to removing fluorine from the high-salt and high-fluorine wastewater.When n(Al/F)is equal to 5.0,the concentration of fluorine ion in the supernatant is 2.7 mg/L,and the optimal pH value is about 6.5~7.5.The method of chemical precipitation and coagulation precipitation has a good synergistic treatment effect on the impurity ions in the high-salt and fluorine-containing wastewater after the wet treatment of aluminum spent lining,which provides a broader space for the subsequent treatment and high value utilization of high-salt solution.