Comprehensive Utilization of Ludwigite Ore Based on Metallizing Reduction and Magnetic Separation

With the aim of high-efficiency utilization of Dandong ludwigite ore, a new process of metallizing reduction and magnetic separation was proposed, and the effects of reduction temperature, reduction time, carbon ratio, ore size and coal size on the efficiency of the process were investigated in details, and relevant mechanisms were elucidated by SEM and EDS. The optimum technological parameters for metallizing reduction and magnetic separation on ludwigite ore were obtained as reduction temperature of 1 250 °C, reduction time of 60 min, carbon ratio of 1.4, ore size of 0.500–2.000 mm, and coal size of 0.50–1.50 mm. After adopting the optimum parameters, the iron content and recovery ratio of iron in magnetic substance are 87.78% and 88.02%, respectively, while the recovery ratios of boron, magnesium and silicon in non-magnetic substance are 88.86%, 94.60% and 98.66%, respectively. After metallizing reduction and magnetic separation, valuable elements of ludwigite ore could be separated and utilized in subsequent steelmaking process and hydrometallurgy process.