锌精矿与锌浸出渣加压协同助浸过程优化及动力学研究  

Optimization and Kinetics Study of Synergistic Pressure-assisted Leaching Process between Zinc Concentrate and Zinc Leaching Residue

作　　者：李倡纹 李存兄[1] 戴兴征 陆占清 王启亮 陈帮耀 宋健清 成圳 LI Changwen;LI Cunxiong;DAI Xingzheng;LU Zhanqing;WANG Qiliang;CHEN Bangyao;SONG Jianqing;CHENG Zhen(Faculty of Metallurgical and Energy Engineering,Kunming University of Science and Technology,Kunming 650093,China;Yunnan Chihong Zn&Ge Co.,Ltd.,Qujing 655011,Yunnan,China)

机构地区：[1]昆明理工大学冶金与能源工程学院,昆明650093 [2]云南驰宏锌锗股份有限公司,云南曲靖655011

出　　处：《有色金属（冶炼部分）》2024年第10期38-48,共11页Nonferrous Metals（Extractive Metallurgy)

基　　金：国家重点研发计划项目(2021YFC2902801);国家自然科学基金资助项目(52474381,52064034);云南省重点研发计划资助项目(202202AB080005,202202AG050008,202302AB080017)。

摘　　要：针对现有锌精矿加压浸出过程氧气利用率低、闪锌矿溶解缓慢等问题,利用锌浸出渣中Fe^(3+)的强氧化性以及Fe^(2+)/Fe^(3+)氧化还原离子对输氧效能,提高闪锌矿中S2-的高效氧化和O2利用率,实现锌精矿与锌浸出渣协同强化浸出。研究结果表明,Fe^(3+)可以提高氧气溶解度,同时Fe^(2+)/Fe^(3+)的往返变价行为加速了浸出体系中闪锌矿(ZnS)的氧化溶解,锌的浸出速率和浸出率得到显著提升。以锌浸出渣形式向体系添加6.1 g/L Fe^(3+)、在初始硫酸浓度95 g/L、氧分压0.8 MPa、反应温度160℃、反应时间120 min的优化条件下,锌浸出率可以达到98.60%,同时92.47%的铁沉淀入渣。锌精矿与锌浸出渣协同助浸受外扩散控制,表观活化能为15.61 kJ/mol,协同浸出的动力学方程为:1-(1-α)^(1/3)=4.78×10^(-3)×{[exp(-15610/8.314T)]×c(H_(2)SO_(4))1.21×P(O_(2))0.33×c(Fe^(3+))0.43×t}。Aiming at the problems of low oxygen utilization rate and slow dissolution of sphalerite in the pressure leaching process of zinc concentrate,the strong oxidizability of Fe ^(3+)in zinc leaching residue and the oxygen transport efficiency of Fe ^(2+)Fe ^(3+)redox ion pair were used to improve the efficient oxidation of S 2-in sphalerite and the utilization rate of O 2,so as to realize the synergistic enhanced leaching of zinc concentrate and zinc leaching residue.The results show that Fe ^(3+)can improve the solubility of oxygen,and the back-and-forth valence behavior of Fe ^(2+)Fe ^(3+)accelerates the oxidative dissolution of sphalerite(ZnS)in the leaching system,and the leaching rate and leaching efficiency of zinc are significantly improved.Under the optimal process conditions of initial sulphuric acid concentration of 95 g L,oxygen partial pressure of 0.8 MPa,temperature of 160℃,reaction time of 120 min,and pH value of 3,and the addition of 6.1 g L Fe ^(3+)in the form of zinc leaching residue results in a high leaching rate of 98.60%of zinc,and 92.47%of iron is precipitated into the residue.The synergic leaching of zinc concentrate and zinc leaching residue is controlled by external diffusion with apparent activation energy of 15.61 kJ mol.The kinetic equation of synergic leaching process is as follows:1-(1-α)^(1/3)=4.78×10^(-3)×{[exp(-15610/8.314T)]×c(H_(2)SO_(4))1.21×P(O_(2))0.33×c(Fe^(3+))0.43×t}.

关 键 词：锌精矿 加压浸出 锌浸出渣 动力学 

分 类 号：TF813[冶金工程—有色金属冶金]