铜复杂资源造锍熔炼过程中MgO对铜锍和二氧化硅饱和铁硅渣相平衡的影响  

Effect of MgO on phase equilibria of copper matte and SiO_(2)-saturated iron silicate slag in smelting complicated copper resources

作　　者：田苗 王琼琼 王亲猛 李伟 郭学益 Miao TIAN;Qiong-qiong WANG;Qin-meng WANG;Wei LI;Xue-yi GUO(School of Metallurgy and Environment,Central South University,Changsha 410083,China;National&Regional Joint Engineering Research Center of Nonferrous Metal Resources Recycling,Changsha 410083,China;Daye Nonferrous Metals Co.,Ltd.,Huangshi 435000,China)

机构地区：[1]中南大学冶金与环境学院,长沙410083 [2]有色金属资源循环利用国家地方联合工程研究中心,长沙410083 [3]大冶有色金属有限责任公司,黄石435000

出　　处：《Transactions of Nonferrous Metals Society of China》2023年第11期3544-3559,共16页中国有色金属学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.U20A20273);the Natural Science Foundation for Distinguished Young Scholars of Hunan Province,China(No.2022JJ10078);the Innovation Driven Project of Central South University,China(No.2020CX028).

摘　　要：采用高温平衡实验及电子探针微区分析方法研究铜复杂资源中MgO对造锍熔炼平衡体系铜锍及熔炼渣成分(FeO_(x)-SiO_(2)-MgO)的影响。结果表明,在1300℃、p(SO_(2))=10kPa熔炼条件下,增加熔炼渣中MgO含量可降低渣中FeO的活度,进而降低渣中氧分压(p(O_(2)))、减少铜在渣中化学溶解损失量;同时,渣中FeO活度降低可促进铜锍中FeS氧化进渣,提高铜锍品位。在高硅渣型中,过量MgO易在渣中形成固相夹杂颗粒(Mg_(2)SiO_(4)-Fe_(2)SiO_(4)),导致渣黏度升高、增加渣中铜损失。当熔炼温度由1200℃升至1300℃及p(O_(2))为10-6kPa时,FeO_(x)-SiO_(2)-MgO渣中MgO的最大溶解量由3%增至8%(质量分数);渣中MgO含量增加时,可通过添加SiO_(2)熔剂调整渣型、升高熔炼温度,进而降低渣中固相析出物含量,改善熔渣性质。The effect of MgO on the phase equilibria between matte and tridymite-saturated FeO_(x)-SiO_(2)-MgO slag was investigated using high-temperature equilibration and microanalysis technique.The results showed that at 1300℃ and p(SO_(2))of 10 kPa,the presence of MgO reduced the FeO activity of the slag,leading to the decrease in the oxygen partial pressure(p(O_(2)))over the slag and the Cu solubility in the slag.Due to the lower FeO activity,FeS was oxidized from matte into slag,increasing the Cu concentration of the matte.In high-SiO_(2) concentration slags,excessive MgO in the liquid slag recrystallized as solid olivine(Mg_(2)SiO_(4)-Fe_(2)SiO_(4)),increasing the slag viscosity and copper losses in the slag.The maximum MgO solubility in the FeO_(x)-SiO_(2)-MgO slag increased from 3 wt.%to 8 wt.%when the temperature raised from 1200 to 1300℃ under p(O_(2))of 10-6 kPa.At higher MgO content,the slag composition could be optimized by increasing temperature and adding SiO_(2) flux to maintain a fully molten slag or avoid high proportions of solids.

关 键 词：氧化镁 铁橄榄石渣 铜锍熔炼 相平衡 元素分布 

分 类 号：TF811[冶金工程—有色金属冶金]