【摘要】 本文采用硫酸铵焙烧-水浸工艺,将红土镍矿与硫酸铵混合焙烧,研究了焙烧温度、焙烧时间、物料配比和矿粉粒度对镍、镁、铝和铁提取率的影响.采用正交实验优化工艺条件,得到影响焙烧效果的各因素顺序为:物料配比、焙烧时间、焙烧温度、矿粉粒度.优化工艺条件为:焙烧温度450℃,焙烧时间120min,物料配比2∶1,矿粉粒度小于80μm,镍、镁和铝提取率大于98%,铁提取率大于94%.研究了焙烧过程镍、镁、铝和铁与硫酸铵反应过程的动力学.镍、镁、铝和铁的反应速率均符合未反应收缩核模型,表观活化能分别为19.93 k J·mol^-1、18.96 k J·mol^-1、17.86 k J·mol^-1和20.83 k J·mol^-1.更多还原

【Abstract】 An ammonium sulfate roasting-water leaching process was used to extract nickel,magnesium,aluminum and iron.Effects of roasting temperature,roasting time,ratio of ammonium sulfate to ore and particle size were studied.The orthogonal experimental results showed that the order of factors affecting the roasting process is the ratio of ammonium sulfate to the ore,roasting time,roasting temperature,particle size.The optimal conditions is: the roasting temperature is 450 ℃,the roasting time is 120 min,the ratio of ammonium sulfate the ore is 2∶1 and the particle size of the ore is less than 80 μm.The extraction ratios of nickel,magnesium and aluminum are over 98%,the extraction ratio of iron is over than 94%.The kinetics of the roasting process was studied.The results showed that the reactions of nickel,magnesium,aluminum and iron suit to the shrink unreacted core model controlled by internal diffusion.The apparent activation energy are 19.93 kJ·mol^-1,18.96 kJ·mol^-1,17.86 kJ·mol^-1 and 20.83 kJ·mol^-1,respectively.更多还原