Influence of laterite nickel ore on extracting iron from Bayer red mud by carbothermal smelting reduction

Abstract

In view of the difficulty of extracting iron from Bayer red mud, a new idea of adding laterite nickel ore into red mud was proposed to prepare a high value-added product. Toward this, the influences of laterite nickel ore on thermodynamic reaction, slagging and smelting reduction of extracting iron from red mud were studied. The results indicated that the product of extracting iron from red mud (R100) was changed with the addition of laterite nickel ore (R70L30). The slag of R100 was strongly basic, while the R70L30 was weakly acidic with composition closer to the ideal blast furnace slag. The metal recovery of R100 was 75.16% and that of R70L30 was 94.05%. At the same temperature, the slag viscosity of R70L30 was significantly lower than that of R100, which proved that laterite nickel ore can adjust the basicity, reduce melting point of slag and improve metal recovery. Because Fe, Ni and Cr in red mud and laterite nickel ore can be reduced sufficiently, a low Ni–Cr alloy cast iron can be directly prepared.