Abstract: The migration and precipitation of Fe components in the copper slag from a copper smelter were studied by a high temperature oxidation method. The effects of oxygen flow rate, time and temperature on the migration and precipitation were systematically examined. Phase composition and morphology of the modified slag were examined with XRD and SEM, and the grain size and volume fraction of magnetite phase measured. The results showed that the migration, enrichment, precipitation and growth of Fe components in the slag could be improved by prolonging oxidation time and increasing oxygen flow rate and temperature. The optimal conditions were obtained as modification temperature at 1653 K, oxygen flow rate 7 L/min and oxidation time 6 min, so the grain size could be increased from 20 to 80 mm, and the volume fraction from 20% to 50%, the iron concentrate of 54%(w) Fe at 90% recovery rate could be obtained by magnetic separation process.

Key words: copper smelting slag, iron, oxidation, magnetite, enrichment

摘要： 采用高温氧化改性方法，以某铜冶炼厂铜冶炼熔渣为原料，研究了渣中铁组分的迁移与析出行为. 考察了氧化时间、氧气流量与温度对铁组分迁移与析出行为的影响，分析了改性前后渣中物相组成及形貌，测定了磁铁矿相的晶体大小和体积分数. 结果表明，延长氧化时间、增加氧气流量及提高氧化温度均有利于渣中铁组分的迁移、富集、析出与长大，优化条件为温度1653 K、氧气流量7 L/min、氧化时间6 min，在此条件下，磁铁矿相的晶粒度由20 mm提高到80 mm、体积分数由20%提高到50%；经磁选分离得到54%(w)的铁精矿，回收率为90%左右.

关键词: 铜渣, 铁, 氧化, 磁铁矿, 富集