钒渣钙化焙烧的影响因素及焙烧氧化动力学

采用钙化焙烧方式处理转炉钒渣以提高钒的浸出率，考察了焙烧参数(渣样粒度，升温速率，焙烧保温温度及保温时间，配钙量)对钒浸出率的影响，根据钒渣氧化的TG-DSC曲线对钒渣氧化变温动力学进行了分析.结果表明:降低升温速率可提高钒氧化率，保温温度高于600℃时钒浸出率迅速增加.在钒渣粒径48~75μm，外配钙m(CaO)/m(V2O5)为042，升温速率2℃·min-1，保温温度850℃，保温时间150min的条件下，钒浸出率达9331%.钒尖晶石氧化过程受三级化学反应控制，升温速率为5和10℃·min-1的表观活化能分别为26765，25603kJ·mol-1.

Influencing Factors of Vanadium Slag Roasting with Calcium and Oxidation Kinetics for Roasting Process

Vanadium slag was treated by calcium roasting to improve the vanadium leaching rate. The effects of the operational parameters including particle size， heating rate， holding temperature， holding time and amount of additive of CaO on the roasting efficiency were investigated. The oxidation kinetics of vanadium slag was analyzed on the basis of TG-DSC curves. The results indicated that lowering heating rate is beneficial to improve the vanadium oxidation efficiency， and the vanadium leaching rate increases markedly when the holding temperature is higher than 600℃. The vanadium leaching rate reaches to 9331% under the optimum conditions of the particle size of 48~75μm， m(CaO)/m(V2O5)=042， the heating rate of 2℃·min-1， the holding time of 150 min at 850℃. The oxidation process of vanadium spinel is described by a third order reaction and the apparent activation energies at the heating rates of 5 and 10℃·min-1 are 26765 and 25603kJ·mol-1， respectively.