Abstract: The industrial mineralogy of copper-containing slag from copper smelting reverberatory furnace was studied using X-ray fluorescence spectrometer, X-ray diffractometer, scanning electron microscope coupled with energy dispersive spectroscope, M?ssbauer spectroscope and optical microscope. The slag contained 1.06% Cu and 36.41% Fe. Copper was mainly in the form of copper matte, and fayalite at 53.5% was the dominant iron phase. The microscopic analysis indicated the major copper, iron and silicon phases in the slag were unevenly distributed and in close paragenesis. Thermodynamic analysis demonstrated that fayalite tended to convert into magnetic iron oxides in the presence of CaO and O2. An efficient treatment of the slag was proposed using copper flotation, silica removal by smelting and subsequent magnetic separation. The copper recovery rate after flotation increased from 18.6% to 39.02% at a copper concentrate grade of 4.6% when the sample was ground from 75% to 95% passing 74 mm. Silica removal was conducted for 30 min smelting at a molar ratio of 0.9 for CaO/SiO2 in the charge and 1350℃. At a cooling rate of 10 K/min, the formed matte was then crushed and ground for subsequent magnetic separation of iron phases. An iron concentration of 62% was obtained at a recovery rate of 71%.

Key words: water-quenched slag, matte, fayalite, flotation, magnetic separation

摘要： 采用XRF, XRD, SEM-EDS, M?ssbauer及金相显微分析等对炼铜反射炉水淬渣进行了工艺矿物学研究. 结果表明，渣中含铜1.06%(w)，主要以冰铜存在；全铁量为36.41%(w)，Fe2SiO4占53.5%(w)，Fe3O4为32.5%(w)，Fe2O3为14.0%(w)，且铜、铁、硅矿物紧密共生，呈细粒不均匀嵌布. 热力学分析表明，在CaO和O2存在条件下，硅酸铁转化为磁性氧化铁的趋势较大. 采用浮选回收铜-高温脱硅-磁选分离铁的选冶工艺处理炉渣，当磨矿细度-0.074 mm含量从75%增加到95%时，一次粗选铜回收率从18.6%增至39.02%，粗选精矿铜品位为4.6%. 炉渣在CaO/SiO2摩尔比0.9、1350℃氧化30 min、10 K/min缓冷速度下脱硅后，经破碎、磨矿、磁选，铁回收率为71%，铁精矿品位达62%.

关键词: 水淬渣, 冰铜, 硅酸铁, 浮选, 磁选