ACCESS
This paper explores the effects of reductant, flux, reduction temperature and reduction time on the iron content and iron recovery rate of the deep reduction product from copper slag containing 41.47% of iron. Through a series of tests, it is concluded that reduction temperature and reduction time are leading influencing factors on the two indices of the product. Magnetic metallic iron powder with low S and P contents, high iron content (92.96%) and high iron recovery rate (93.49%) were produced through deep reduction magnetic separation using coke powder as reductant and CaO as flux under 1,300 °C for 2h. The scanning electron microscopy (SEM) and energy-dispersive spectrometry (EDS) patterns show that the metal iron particles were uniform in particle size, regular in shape and simple in intercalation relationship, with no inclusion of other slag phases, making it easy to achieve monomer dissociation by grinding.
copper slag, deep reduction, iron recovery, magnetic separation, metallic iron
Alter H. (2005). The composition and environmental hazard of copper slag in the context of the Basel convention. Resources, Conservation and Recycling, Vol. 43, No. 4, pp. 353-360. https://doi.org/10.1016/j.resconrec.2004.05.005
Gorai B., Jana R. K., Premchand. (2003). Characteristics and utilisation of copper slag—a review. Resources Conservation & Recycling, Vol. 39, No. 4, pp. 299-313. https://doi.org/10.1016/S0921-3449(02)00171-4
Guo Z. Q., Zhu D. Q., Pan J., Zhang F. (2017). Co-reduction of copper smelting slag and nickel laterite to prepare Fe-Ni-Cu alloy for weathering steel. The Journal of the Minerals, Metals & Materials Society, Vol. 70, No. 4, pp. 1-5. https://doi.org/10.1007/s11837-017-2641-y
Guo Z. Q., Zhu D. Q., Pan J., Zhang F. (2018). Innovative methodology for comprehensive and harmless utilization of waste copper slag via selective reduction-magnetic separation process. Journal of Cleaner Production, Vol. 187, pp. 910-922. https://doi.org/10.1016/j.jclepro.2018.03.264
Guo Z. Q., Zhu D. Q., Pan J., Wu T. J., Zhang F. (2016). Improving beneficiation of copper and iron from copper slag by modifying the molten copper slag. Metals, Vol. 6, No. 4, pp. 86-102. https://doi.org/10.3390/met6040086
Gyurov S., Kostova Y., Klitcheva G., Ilinkina A. (2011). Thermal decomposition of pyrometallurgical copper slag by oxidation in synthetic air. Waste Management & Research, Vol. 29, No. 2, pp. 157-164. https://doi.org/10.1177/0734242X10379495
Jiao R. M., Xing P., Wang C. Y., Ma B. Z., Chen Y. Q. (2017). Recovery of iron from copper tailings via low-temperature direct reduction and magnetic separation: process optimization and mineralogical study. International Journal of Minerals, Metallurgy, and Materials, Vol. 24, No. 9, pp. 974-982. https://doi.org/10.1007/s12613-017-1485-3
Komkov A. A., Kamkin R. I. (2010). Mathematical model of behavior of impurities under the conditions of reducing bubble processing of copper smelting slags. Russian Journal of Non-Ferrous Metals, Vol. 51, No. 1, pp. 26-31. https://doi.org/10.3103/S1067821210010050
Li K. Q., Ping S., Wang H. Y., Ni W. (2013). Recovery of iron from copper slag by deep reduction and magnetic beneficiation. International Journal of Minerals Metallurgy and Materials, Vol. 20, No. 11, pp. 1035-1041. https://doi.org/10.1007/s12613-013-0831-3
Li L., Hu J. H., Wang H. (2011). Study on smelting reduction ironmaking of copper slag. The Chinese Journal of Process Engineering, Vol. 11, No. 1, pp. 65-71. (in China)
Lowinska-Kluge A., Piszora P., Darul J., Kantel T., Gambal P. (2011). Characterization of chemical and physical parameters of post copper slag. Central European Journal of Physics, Vol. 9, No. 2, pp. 380-386. https://doi.org/10.2478/s11534-011-0010-y
Maweja K., Mukongo T., Mutombo I. (2009). Cleaning of a copper matte smelting slag from a water-jacket furnace by direct reduction of heavy metals. Journal of Hazardous Materials, Vol. 164, No. 2, pp. 856-862. https://doi.org/10.1016/j.jhazmat.2008.08.107
Najimi M., Pourkhorshidi A. (2011). Properties of concrete containing copper slag waste. Magazine of Concrete Research, Vol. 63, No. 8, pp. 605-615. https://doi.org/10.1680/macr.2011.63.8.605
Ni W., Jia Y., Xu C. Y., Zheng M. J., Wang Z. J. (2010). Beneficiation of unwieldy oolitic hematite by deep reduction and magnetic separation process. Journal of University of Science and Technology Beijing, Vol. 32, No. 3, pp. 287-291. (in China)
Tran L., Palacios J., Sanches M. (2012). Recovery of Molybdenum from copper slag. Tetsu to Hagane-Journal of the Iron and Steel Institute of Japan, Vol. 98, No. 2, pp. 48-54. https://doi.org/10.2355/isijinternational.52.1211
Wang S., Wang C. L., Wang Q. H., Ni W., Li K. Q. (2017). Optimization and microstructure study of the reduction of nickel smelting slag mixed with calcium carbide slag and coke dust for recovering iron. Chemical Engineering Transactions, Vol. 62, No. 62, pp. 55-60. https://doi.org/10.3303/CET1762010
Yang H. F., Jing L. L., Zhang B. G. (2010). Recovery of Fe from vanadium tailings with coal-based direct reduction followed by magnetic separation. Journal of Hazardous Materials, Vol. 185, No. 2-3, pp. 1405-1411. https://doi.org/10.1016/j.jhazmat.2010.10.062
Zhou X. L., Zhu D. Q., Pan J., Wu T. J. (2015). Utilization of waste copper slag to produce diretly reduced iron for weathering resistant steel. The Iron and Steel Institute of Japan, Vol. 55, pp. 1347-1352. https://doi.org/10.13140/RG.2.1.4436.3368