KMnO4预氧化与混凝联合作用去除湖泊源水中Mn^2＋的研究

Removal of Mn^(2+) from Lake Water Source by Combined Oxidation with KMnO_4 and Coagulation

以外加Mn^(2+)湖水为研究对象,研究了KMnO_4预氧化与混凝去除湖泊源水中的Mn^(2+),考察了浊度、COD_(Mn)、p H、水中共存离子等水质参数以及混凝剂对除锰效率的影响,并探讨了预氧化产物新生态二氧化锰对混凝剂除浊投量的影响。结果表明:KMn O_4投量为理论值的83%或更低时剩余Mn^(2+)达标;KMnO_4与Mn^(2+)反应2 min内达到平衡;湖水COD_(Mn)变化对锰的去除率基本无影响;浊度对除锰有一定促进作用,但随着高锰酸钾投量增加逐渐减小;p H增大高锰酸钾对锰去除率上升,初始p H从6.54增加至9.57,95%锰去除率所需高锰酸钾投量从1.6 mg/L降低至0.8mg/L;Fe^(3+)/Al^(3+)离子混凝剂、HCO_3^-、H_2PO_4^-、SiO_3^(2-)对Mn^(2+)去除有一定影响;KMnO_4预氧化除Mn^(2+)产物水合二氧化锰可节省混凝除浊29%硫酸铝或43%聚合氯化铝铁投量。

The lake water with added Mn^2＋ was used as the research object, the effect of turbidity, CODMn, pH, coexisting ions and coagulants on Mn^2＋ removal by KMnO4 were investigated, the effect of coagulants dosage was also discussed while the new-formed manganese dioxide produced in the process of the pre-oxidation was existing. The result show that 95% or more Mn^2＋ has been removed when the dosage of KMnO4 was 83% or less of the calculated; the reaction between KMnO4 and Mn^2＋ quickly occurred and the balance achieved simultaneously in 2 min; The CODMn change of the lake water has less influence of on Mn^2＋ removal; The turbidity could promote Mn^2＋ removal rate, but the rate promoted by turbidity decreased as KMnO4 dosage increasing; Mnz＋ removal rate was increasing as pH value increasing, initial pH value was 6.54 and 9.57, KMnO4 dosage of 95% Mn^2＋ removal was 1.6 mg/L and 0.8 mg/L separated; Fe3＋/Al3＋ ion coagulants, HCO3-, H2PO4-, SiO3^2- has some influence on Mn^2＋ removal; Hydrated manganese dioxide could reduce 29% A12（SO4）3 or 43% PAFC dosage for turbidity removal.