褐铁型红土镍矿有价组分梯级分离及利用：铁/铬富集－分离新技术基础

镍、钴、铬和钢铁是重要的战略金属，我国相应资源对外依存度分别高达83%、95%、95%和88%。褐铁型红土镍矿是主要的镍、钴矿产资源，也是重要的铁、铬伴生资源，但潜在价值未充分利用。鉴于传统工艺存在资源利用率低、试剂消耗量大和经济性差等问题，结合前期研究，构思了褐铁型红土镍矿有价组分梯级分离及利用技术方案。本项目就其核心工序“铁/铬富集—分离”的科学问题：①促进剂转化行为及与组成矿物表界面更新/转变、相结构破坏耦合关系；②诱使铁组元以氧化物形式先迁移/聚集后还原/聚合的驱动力及作用机理；③酸浸富铁/铬渣非熔融态选择性金属化还原过程动力学及调控机制；④新构矿物相界面特性对磁选分离铁与铬/硅/铝等组元的影响规律等展开系统研究。基于此，建立富铁/铬渣煤基非熔融态选择性金属化还原－磁选分离铁/铬理论基础，完善新技术理论体系，促进该原创性技术工业应用，解决我国战略金属短缺和降低国内企业海外投资风险。

Nickel, cobalt, chromium and steel are important strategic metals, however our country's dependence on foreign resources of them are as high as 83%, 95%, 95% and 88%, respectively. Limonitic laterite ores are the dominant nickel-cobalt bearing mineral resources and also most commonly presented as important iron and chromium accompanying resources, nevertheless, their potential value has not been fully utilized. Given that traditional laterite treatments suffer from many predicaments, such as low resource utilization, large reagent consumption and bad economical efficiency, a technology conception of gradient separation and utilization of valuable components from limonitic laterite is proposed based on the previous investigations. This project concerns the scientific foundations for the key process，beneficiation and separation of iron over chromium, of this innovative technology: (1) promoter transformation behavior and the coupling relation between this behavior and surface/interface transformation, structure dissociative of minerals; (2) induction force and action mechanism of the target element, iron, migrating and aggregating firstly in the form of iron oxides followed by reducing and fusing together; (3) transmission dynamics and regulatory mechanism of leach residue being selectively metallized reduction process in non-molten state; (4) effect of the interface feature of the new mineral structures on magnetic separating iron over chromium, silicon, aluminum, etc. Based on these systematic investigations, the theoretical basis of coal based selectively metallized reduction of iron- and chromium-contained residue in a non-molten state and magnetic separation of iron over chromium will be found, and the foundations of the innovative technology will be integrated, and the commercial application of the original technology will be accelerated. In addition, the project will be beneficial to solve the shortage of strategic metal in our country and reduce the risk of domestic enterprises' overseas investment.