利用二元钠盐体系处理钒渣的清洁焙烧工艺

试验研究了利用二元钠盐(NaOH-Na₂CO₃)对钒渣进行焙烧，并分析了相关动力学参数对焙烧效果的影响.结果表明:在二元钠盐焙烧过程中，焙烧温度、焙烧时间及NaOH与Na₂CO₃质量比对渣中钒、铬的浸出率影响重大;焙烧过程中，Fe₃O₄被氧化为Fe₂O₃，V₂O₅和Cr₂O₃分别被氧化为β钒酸钠型结构的Na₃VO₄与正交晶系结构的Na₂CrO₄;最佳焙烧条件下，NaOH与 Na₂CO₃质量比为1.5∶1，焙烧温度为600℃，焙烧时间为60min，此时钒与铬的浸出率分别为98.66%与83.57%;浸出尾渣的主要金属元素为Fe.

Clean Roasting Process for Treating Vanadium Slag by Using Binary Sodium Salts System

The vanadium slag was treated by NaOH-Na₂CO₃ binary sodium salts in the roasting process and the influence of related kinetic parameters on roasting effect was investigated. The results showed that during the NaOH-Na₂CO₃ binary roasting process， the roasting temperature， roasting time and NaOH to Na₂CO₃ mass ratio play significant roles in the extraction rate of vanadium and chromium. The ferriferous oxide(Fe₃O₄)is oxidized to ferric oxide(Fe₂O₃)while V₂O₅ and Cr₂O₃ are converted to the β-natrium-vanadate type structure of Na₃VO₄ and orthorhombic-type crystal structure of Na₂CrO₄， respectively. Under the optimum roasting conditions(roasting temperature of 600℃， roasting time of 60min， and NaOH to Na₂CO₃ mass ratio of 1.5∶1)， the extraction rate of vanadium and chromium is 98.66% and 83.57%， respectively. The major metal element in the leaching residue is Fe.