铅锌矿选矿废水的处理及循环利用

采用聚合硫酸铁(PFS)和PFS-FeSO4复合混凝剂处理铅锌矿选矿废水。结果表明:采用PFS处理选矿废水,当剂量(以铁计)为56 mg.L-1时,Cu,Pb和浊度去除率分别可达90.63%,99.97%和100%,但Cr去除率仅为24.98%;采用PFS-FeSO4复合混凝剂处理选矿废水,当剂量(以铁计)分别为42和780 mg.L-1时,Cu和Pb去除率分别为81.25%和99.97%,Cr去除率达到88.74%,但浊度去除率下降至86.06%;当剂量(以铁计)为84 mg.L-1,并在0.5 L废水中加入0.5 g Na2S时,Cu,Pb,Cr和浊度去除率分别为84.69%,99.97%,98.9%和99.14%,去除Cr效果显著增加,处理后选矿废水中的Cu,Pb,Zn和Cr含量低于国家污水综合排放标准(GB8978-1996)。工业放大实验结果表明,处理后废水可循环利用。

Treating and recycling of wastewater from lead-zinc mineral processing plant

Lead-zinc mineral processing wastewater was treated by polymeric ferric sulfate(PFS) and a complex coagulant of PFS-FeSO4.The results show that after the wastewater is treated by PFS and the dosage of total iron is 56 mg.L-1,the removal rates of Cu,Pb and turbidity are up to 90.63%,99.97% and 100%,respectively,while the removal rate of Cr is only 24.98%.After the wastewater is treated by PFS-FeSO4 and the dosages of total iron of PFS and FeSO4 are separately 42 and 780 mg.L-1,the removal rates of Cu and Pb are 81.25% and 99.97%,and the removal rate of Cr is up to 88.74%,but the removal rate of turbidity is down to 86.06%.After the wastewater is treated by PFS-FeSO4,and 0.5 g sodium sulfide(Na2S) is added into 0.5 L wastewater and the dosage of total iron is 84 mg.L-1,the removal rates of Cu,Pb,Cr and turbidity are up to 84.69%,99.97%,98.9% and 99.14%,respectively.The surplus concentrations of Cu,Pb,Zn and Cr of the wastewater treated by the complex coagulant of PFS-FeSO4 and Na2S are under the Chinese standards of wastewater discharge(GB8978-1996).The industrial experimental proves that the treated wastewater can be recycled.