Transformation of Ferrous Minerals from Vanadium Tailings in Reduction Roasting
Vanadium tailings are one of the most hazardous solid wastes due to high content of alkaline oxides such as Na2O and K2O, but also are secondary iron ore resources due to more than 30% total iron content.Iron-bearing minerals mainly were hematite (Fe2O3), pseudobrookite (Fe2TiO5) and acmite (NaFe(SiO3)2).Transformation of these iron-bearing minerals in direct reduction roasting was investigated in this study for recovering and reusing iron.Effects of reduction roasting parameters on transformation of iron-bearing minerals were determined based on XRD.Under reduction conditions as follows: weight ratios of vanadium tailings/lignite/lime at 100:30:10, reduction at 1200℃ for 60min, hematite was completely reduced to metallic iron based on XRD.However pseudobrookite was firstly reduced to intermediate ilmenite (FeTiO3), and then further reduced to metallic iron with the help of CaO.The acmite (NaFe(SiO3)2) was mostly decomposed.Metallic iron particles obtained after direct reduction, with majority of particle size bigger than 5 μm, were loosely scattered on slag particle surface based on SEM.Therefore, Metallic iron particles can be easily recovered by magnetic separation after grinding.
vanadium tailings direct reduction iron-bearing minerals transformation recovery iron
Huifen YANG Lili JING Wen MA Feng WANG
School of Civil and Environmental Engineering University of Science and Technology Beijing Beijing 100083, China
国内会议
北京
英文
349-352
2010-12-18(万方平台首次上网日期,不代表论文的发表时间)