Feasibility of co-reduction roasting of a saprolitic laterite ore and waste red mud

Abstract

Large scale utilization is still an urgent problem for waste red mud with a high content of alkaline metal component in the future. Laterite ores especially the saprolitic laterite ore are one refractory nickel resource, the nickel and iron of which can be effectively recovered by direct reduction and magnetic separation. Alkaline metal salts were usually added to enhance reduction of laterite ores. The feasibility of co-reduction roasting of a saprolitic laterite ore and red mud was investigated. Results show that the red mud addition promoted the reduction of the saprolitic laterite ore and the iron ores in the red mud were co-reduced and recovered. By adding 35wt% red mud, the nickel grade and recovery were 4.90wt% and 95.25wt%, and the corresponding iron grade and total recovery were 71.00wt% and 93.77wt%, respectively. The X-ray diffraction (XRD), scanning electron microscopy, and energy dispersive spectroscopy (SEM-EDS) analysis results revealed that red mud addition was helpful to increase the liquid phase and ferronickel grain growth. The chemical compositions “CaO and Na₂O” in the red mud replaced FeO to react with SiO₂ and MgSiO₃ to form augite.

Keywords

laterite ore / red mud / reduction roasting / phase transformation

References

[1] Pickles C.A., Elliott R. Thermodynamic analysis of selective reduction of nickeliferous limonitic laterite ore by carbon monoxide. Miner. Process. Extr. Metall., 2015, 124(4): 208.

[2] Rao M.J., Li G.H., Jiang T., Luo J., Zhang Y.B., Fan X.H. Carbothermic reduction of nickeliferous laterite ores for nickel pig iron production in China: a review. JOM, 2013, 65(11): 1573.

[3] Rao M.J., Li G.H., Zhang X., Luo J., Peng Z.W., Jiang T. Reductive roasting of nickel laterite ore with sodium sulphate for Fe-Ni production. Part II: Phase transformation and grain growth. Sep. Sci. Technol., 2016, 51(10): 1727.

[4] Liang W., Wang H., Fu J.G., He Z.X. High recovery of ferro-nickel from low grade nickel laterite ore. J. Cent. South Univ. Sci. Technol., 2011, 42(8): 2173.

[5] Huang D.H., Zhang J.L., Mao R., Cao M.M. Thermal behaviors and growth of reduced ferronickel particles in carbon-laterite composites. Rare Met., 2011, 30(6): 681.

[6] Li G.H., Luo J., Peng Z.W., Zhang Y.B., Rao M.J., Jiang T. Effect of quaternary basicity on melting behavior and ferronickel particles growth of saprolitic laterite ores in Krupp–Renn process. ISIJ Int., 2015, 55(9): 1828.

[7] Liu Z.G., Sun T.C., Jiang M., Gao E.X. Mechanism of CaO in direct reduction roasting of nickel laterite ore. J. Cent. South Univ. Sci. Technol., 2015, 46(10): 3566.

[8] Li G.H., Shi T.M., Rao M.J., Jiang T., Zhang Y.B. Beneficiation of nickeliferous laterite by reduction roasting in the presence of sodium sulfate. Miner. Eng., 2012, 32, 19.

[9] Li G.H., Rao M.J., Jiang T., Shi T.M., Huang Q.Q. Reduction roasting-magnetic separation mechanisms of nickelferous laterite ore in presence of sodium salts. Chin. J. Nonferrous Met., 2012, 22(1): 274.

[10] Rao M.J., Li G.H., Zhang X., Luo J., Peng Z.W., Jiang T. Reductive roasting of nickel laterite ore with sodium sulfate for Fe-Ni production. Part I: Reduction/sulfidation characteristics. Sep. Sci. Technol., 2016, 51(8): 1408.

[11] Wang X.P., Sun T.C., Chen C., Kou J. Effects of Na₂SO₄ on iron and nickel reduction in a high-iron and low-nickel laterite ore. Int. J. Miner. Metall. Mater., 2018, 25(4): 383.

[12] Lu J., Liu S.J., Ju S.G., Du W.G., Pan F., Yang S. The effect of sodium sulphate on the hydrogen reduction process of nickel laterite ore. Miner. Eng., 2013, 49, 154.

[13] Xue S.G., Zhu F., Kong X.F., Wu C., Huang L., Huang N., Hartley W. A review of the characterization and revegetation of bauxite residues (Red mud). Environ. Sci. Pollut. Res., 2016, 23(2): 1120.

[14] Bento N.I., Santos P.S.C., de Souza T.E., Oliveira L.C.A., Castro C.S. Composites based on PET and red mud residues as catalyst for organic removal from water. J. Hazard. Mater., 2016, 314, 304.

[15] Kurtoğlu S.F., Soyer-Uzun S., Uzun A. Tuning structural characteristics of red mud by simple treatments. Ceram. Int., 2016, 42(15): 17581.

[16] Liu Z.G., Sun T.C., Gao E.X., Wang X.P. Effect of high-temperature phase transition of serpentine mineral on direct reduction roasting of laterite nickel ore. Chin. J. Nonferrous Met., 2015, 5(25): 1332.

[17] Yu W. Study on the Preparation of High-Phosphours Oolitic Hematite-Coal Composite Briquette and its Direct Reduction-Magnetic Separation [Dissertation], 2015, Beijing, University Science and Technology Beijing.