稳定剂对电解锰废渣中高浓度可溶性锰稳定效果的影响

为满足大宗废渣经济性处理的需要,从碱性物质、磷酸盐、碳酸盐类药剂筛选出"物美价廉"稳定剂,考察了Ca O、Mg O和Ca10(PO4)6(OH)2及其与Na HCO3和Na3PO4的组合对电解锰废渣中的可溶性锰的稳定化效果,并采用矿物组成分析、锰价态分析和形态变化探讨可溶性锰固定机理.结果表明:投加10%Mg O锰渣中可溶性锰固定率达到100%,9%Ca O+5%Na HCO3和9%Ca O+5%Na3PO4的组合实现可溶性锰固定率95%以上.上述3组稳定剂将可溶性Mn2+先转变为沉淀态锰进一步转变为高价态含锰物相.后两组中Na HCO3或Na3PO4的加入促进了Mn2+向Mn3+、Mn4+的转化.

Effects of different reagents on the stabilization of soluble manganese from electrolytic manganese solid waste

In order to satisfy the requirement of economical treatment for a large quantity of solid waste, the sort of reagents, such as alkaline materials, phosphate and carbonate, were examined. The immobilization effectiveness of reagents, such as CaO, MgO, and Ca10(PO4)6(OH)2or those reagents in combination with NaHCO3, Na3PO4were investigated. Mineral composition, valence states and speciation of manganese were measured to analyze the stabilization mechanism on soluble manganese. The results showed that the stabilization efficiency of soluble manganese can reach 100% on the condition of 10% addition of magnesium oxide accounting for the mass of EMSW. The immobilization efficiency of soluble manganese could achieve 95% using 9%CaO+5%NaHCO3and 9%CaO+5%Na3PO4. Those stabilizers made the conversion of soluble manganese to precipitated manganese and parts of them to high-charged oxidation products. The addition of CaO in combination with 5%NaHCO3and 5% Na3PO4would be favorable for the transformation of Mn2+ to Mn3+ and Mn4+.