石灰沉淀法对重金属矿坑水中氟离子的去除

为揭示石灰沉淀法去除重金属矿坑水中氟离子的规律,以含氟矿坑水为研究对象,考察了混凝剂投加、沉淀时间、反应初始pH、石灰投加量等操作条件对氟离子去除率的影响。试验结果表明:石灰沉淀法处理矿坑水过程中,聚合氯化铝的投加对氟的去除率影响较小;当沉淀时间为2 h时氟去除率可达50%;随着初始pH的升高,石灰沉淀法对矿坑水中氟离子的去除呈现先降低后升高的变化趋势。当石灰投加量高于3 g/L时,随着石灰投加量的增加,氟离子去除率显著提高。

REMOVAL OF FLUORIDE ION FROM MINING WASTEWATER CONTAINING HEAVY METALS BY LIME PRECIPITATION

In order to explore the law of removal of fluoride ion in the mining wastewater containing heavy metals by lime precipitation,the mining wastewater treatment experiment was conducted,and the effects of operation conditions,such as adding of polyaluminium chloride,precipitation time,initial pH of wastewater and lime dosage on removal rate of fluoride ion,were evaluated.The results showed that the adding of polyaluminium chloride has slight influence on fluoride removal.When the precipitation time was 2 h,the removal rate of fluoride could be up to 50%.The removal of fluoride ion decreased with the increase in initial pH of wastewater at first,and then increases.When the dosage of lime exceeding 3 g/L,the removal rate of fluoride ion increased significantly with the increase in lime dosage.