With the continuous exploitation of primary high-quality mineral resources, these resources could be gradually exhausted, so it is of great significance to recover iron-rich basic oxygen furnace (BOF) slag as secondary mineral resources. Given the composition characteristics of BOF slag, a method of synergetic modification of copper slag as additive and BOF slag was proposed to separate iron minerals for recovery. In this study, FactSage thermodynamic simulation, chemical analysis, X-ray diffraction and scanning electron microscopy were used to analyze the phase transformation and structure evolution during the oxidative modification process, and the effects of oxidation temperature and addition amount of copper slag on the modification were studied. The results show that the addition of copper slag can effectively promote the transformation of iron oxides to MgFe₂O₄. When an appropriate amount of copper slag was added to make the basicity of the mixed slag be 2, the conversion rate of MgFe₂O₄, iron recovery rate and grade of magnetic slag were the best. In the oxidative modification process, increasing the oxidation temperature was beneficial to the formation and development of MgFe₂O₄. However, too high temperature could lead to the dissolution of Al³⁺ into MgFe₂O₄ and reduce its magnetism, which was not conducive to magnetic separation and recovery. When the mixed slag was modified at 1200 ℃, the grade of magnetic slag by magnetic separation was 31.14 % and the recovery was 64.04 %, which had the potential of returning to sintering or ironmaking. The secondary slag obtained at the same time can also be used to produce high value-added materials. Therefore, the current technological route can transform the two kinds of industrial solid waste into usable resources at the same time, and realize "waste treatment with waste".

随着优质初级矿产资源的不断开采，这些资源可能会逐渐枯竭，因此将富铁碱性氧气炉（BOF）渣作为二次矿产资源回收具有重要意义。针对转炉渣的成分特点，提出了铜渣作为添加剂与转炉渣协同改性分离回收铁矿物的方法。本研究采用 FactSage 热力学模拟、化学分析、X 射线衍射和扫描电子显微镜对氧化改性过程中的相变和结构演变进行了分析。研究了氧化温度和铜渣添加量对改性的影响。结果表明，铜渣的加入能有效促进氧化铁向MgFe ₂ O _4的转化。添加适量铜渣使混合渣碱度为2时，MgFe ₂ O ₄转化率、铁回收率和磁渣品位最佳。在氧化改性过程中，提高氧化温度有利于MgFe ₂ O ₄的形成和发展。然而，过高的温度会导致Al ³⁺溶解成MgFe ₂O ₄并降低其磁性，不利于磁选回收。混合渣经1200℃改性后，磁选磁渣品位为31.14%，回收率为64.04%，具有重返烧结或炼铁的潜力。同时获得的二次渣还可用于生产高附加值材料。因此，目前的技术路线可以将两种工业固体废物同时转化为可利用资源，实现“以废治废”。