螯合沉淀法处理含铜、铅废水的研究

Study on Chelating Precipitation to Treat Wastewater Containing Cu^(2+) and Pb^(2+)

采用一种新型的重金属螯合剂五硫代碳酸钠(Na2CS5)处理铜铅废水。探讨五硫代碳酸钠的用量、pH、反应时间等对去除铜铅的影响。结果表明,含Cu2+和Pb2+浓度各为200 mg.L-1的混合模拟废水,当n(Na2CS5)∶n(Cu2++Pb2+)=1.5,pH 5.0,反应15 min,Cu2+和Pb2+去除率各高达99.81%和99.94%,残留的浓度各降至0.38 mg.L-1和0.12 mg.L-1,达到《污水综合排放标准》(GB8978-1996)的一级排放标准。

A new chelating agent, sodium polythiocarbonate, was used in the treatment of wastewater containing Cu2＋ and Pb2＋. The effects of the dosage of Na2CS5, pH value, reaction time on the removal rates of Cu2~ and Pb2＋ were investigated. Results indicated that the removal rates of Cu2＋ and Pb2＋ reached more than 99.81% and 99.94 % respectively, and residual concentrations of Cu2＋ and Pb2＋ were 0.38 mg·L^-1 and 0.12 mg·L^-1, which could meet the first class standard in the national sewage comprehensive discharge standard （GB8978-1996）, when the ratio of the amount of substance of Na2CS5 and the total of Cu2＋ and Pb2＋ was 1.5, the wastewater pH value was 5.0, reaction time was 15 min for Cu2＋ and Pb2＋ concentration of 200mg·L^-1respectively in the simulated wastewater.