冶金渣耦合改质及其金属资源碳热还原提取

Co-modification of metallurgical slags to recover valuable metals by carbothermal reduction

为实现冶金渣中有价金属的高效回收,提出了一种转炉渣与铜渣耦合改质的新工艺.利用高温实验研究了转炉渣与铜渣的耦合改质及碳热还原过程中物相重构规律和元素分离特征,并考察了碱度[w(CaO)/w(SiO_(2) )]、还原温度及碳氧摩尔比[n(C)/n(O)]对金属回收率的影响.结果表明:转炉渣与铜渣的交互作用提高了改质渣中铁氧化物的活度;在碱度为1.25、还原温度为1550℃、碳氧摩尔比为1.2的最佳工艺条件下,可回收得到Fe,Cu,P,Mn质量分数分别为93.19%,3.81%,0.12%,0.10%的合金.

For the effective recovery of valuable metals in metallurgical slags,a novel co-modification method between BOF and copper slag was proposed.The phase reconstruction laws and element separation characteristics during the co-modification and carbothermal reduction process of BOF and copper slag were investigated through high-temperature experiments.The effects of the basicity[w(CaO)/w(SiO_(2) )]of modification,reduction temperature,and molar ratio of carbon and oxygen[n(C)/n(O)]on the metal recovery rate were also investigated.The results show that the interaction between BOF and copper slag increases the activity of iron oxides in the modified slag.Moreover,under the optimal process conditions of modification basicity of 1.25,reduction temperature of 1550℃,and n(C)/n(O)=1.2,an alloy can be recovered with Fe,Cu,P,and Mn contents of 93.19%,3.81%,0.12%,and 0.10%,respectively.