铜渣还原提铁过程中残余元素的行为及熔渣制备微晶玻璃的基础研究

The content of valuable metals in waste copper slag, such as iron and copper, reaches or even exceeds the mining grade of iron ore and copper ore in China, efficient recycling of these wastes is significant to the environmental protection and comprehensive utilization of resources. Carbothermal reduction process is one of the effective methods to achieve of residual elements in the reduced metal products limit its application in steelmaking process, as well as the heat utilization of the secondary melting waste slag in the carbothermal process are urgently required to be utilized. The applicant found that Mo and Cu embedded fragmentary in the metal products of the carbothermal reduction of copper slag. The secondary melted waste slag generated in the carbothermal reduction process has low viscosity, and its chemical compositions are similar with that of typical glass ceramics. In this project, a new method of reduction extraction of iron-reduction of impurities by sulfuration-glass ceramics preparation using molten slag is proposed, the existence forms of residual elements in copper slag are understood, the reduction reaction thermodynamics of residual elements containing phases and phase evolution behavior in the carbothermal reduction process are also analyzed. In addition, the effects of reaction parameters of reduction process on the recovery ratio of valuable elements and distribution behaviour of residual elements in metal-slag are studied. The dynamic mechanism of the carbothermal reduction process would be revealed. The crystallization behaviour and kinetics mechanism in the preparation process of glass ceramics with melted slag, as well as the influence of heat treatment process on the properties of glass ceramics are investigated. Therefore, it would provide a theoretical basis for the value-added utilization of copper slag.

铜渣中铁和铜等有价金属元素含量达到甚至超过了我国铁矿石、铜矿石的可采品位，高效回收利用铜渣对环境保护和资源综合利用都具有重要意义。采用还原提铁工艺是实现铜渣高效增值化利用的有效途径之一，但其中残余元素的存在限制了还原金属产物在炼钢中的应用，还原过程熔融二次尾渣及其热能利用等都是迫切需要解决的问题。申请人发现Mo、Cu等残余元素相零星嵌布于还原金属产物中，且生成的二次熔渣粘度低，其化学成分与矿渣微晶玻璃化学成分相近。本项目提出还原提铁-硫化除杂-熔渣直接制备微晶玻璃的技术，旨在通过探明铜渣中残余元素的赋存形式，分析含残余元素相碳热还原反应热力学及渣相演变行为，揭示还原反应参数对有价元素回收率和残余元素在渣锍铁中分配的影响规律，探明还原过程动力学机理，并揭示熔渣制备微晶玻璃过程的析晶行为、动力学机理及热处理制度对微晶玻璃性能的影响规律，为铜渣高效增值化利用提供理论基础。

铜渣中铁和铜等有价金属元素含量达到甚至超过了我国铁矿石、铜矿石的可采品位，采用还原提铁-硫化除杂-熔渣直接制备微晶玻璃工艺实现铜渣高效增值化利用对环境保护和资源综合利用都具有重要意义。本项目旨在通过探明铜渣中残余元素的赋存形式，分析含残余元素相碳热还原反应热力学及渣相演变行为，揭示还原反应参数对有价元素回收率和残余元素在渣锍铁中分配的影响规律，探明还原过程动力学机理，并揭示熔渣制备微晶玻璃过程的析晶行为、动力学机理及热处理制度对微晶玻璃性能的影响规律，为铜渣高效增值化利用提供理论基础。主要开展了如下研究工作：（1）铜渣中残余元素的赋存形式；（2）铜渣中残余元素在添加剂存在条件下的反应机制；（3）铜渣中含残余元素相的碳热还原行为；（4）铜渣碳热还原反应动力学；（5）铜渣还原提铁除杂过程中残余元素的行为；（6）Fe2O3和ZnO对SiO2-CaO-Al2O3系微晶玻璃结构和性能的影响；（7）热处理制度对铜渣还原尾渣微晶玻璃结构和性能的影响；（8）添加剂对微晶玻璃的析晶行为和动力学机理；（9）铜渣还原尾渣制备微晶玻璃工艺工业化应用潜力评估。