Carbothermic reduction behaviors of Ti–Nb-bearing Fe concentrate from Bayan Obo ore in China
来源期刊：International Journal of Minerals Metallurgy and Materials2018年第1期
论文作者：Guang Wang Ya-xing Du Jing-song Wang Qing-guo Xue
文章页码：28 - 36
摘 要：To support the development of technology to utilize low-grade Ti–Nb-bearing Fe concentrate, the reduction of the concentrate by coal was systematically investigated in the present paper. A liquid phase formed when the Ti–Nb-bearing Fe concentrate/coal composite pellet was reduced at temperatures greater than 1100℃. The addition of CaCO3 improved the reduction rate when the slag basicity was less than 1.0 and inhibited the formation of the liquid phase. Mechanical milling obviously increased the metallization degree compared with that of the standard pellet when reduced under the same conditions. Evolution of the mineral phase composition and microstructure of the reduced Ti–Nb-bearing Fe concentrate/coal composite pellet at 1100℃ were analyzed by X-ray diffraction and scanning electron microscopy–energy-dispersive spectroscopy. The volume shrinkage value of the reduced Ti–Nb-bearing Fe concentrate/coal composite pellet with a basicity of 1.0 was approximately 35.2% when the pellet was reduced at 1100℃ for 20 min, which enhanced the external heat transfer to the lower layers when reduced in a practical rotary hearth furnace. The present work provides key parameters and mechanism understanding for the development of carbothermic reduction technology of a Ti–Nb-bearing Fe concentrate incorporated in a pyrometallurgical utilization flow sheet.
Guang Wang，Ya-xing Du，Jing-song Wang，Qing-guo Xue
State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing
摘 要：To support the development of technology to utilize low-grade Ti–Nb-bearing Fe concentrate, the reduction of the concentrate by coal was systematically investigated in the present paper. A liquid phase formed when the Ti–Nb-bearing Fe concentrate/coal composite pellet was reduced at temperatures greater than 1100℃. The addition of CaCO3 improved the reduction rate when the slag basicity was less than 1.0 and inhibited the formation of the liquid phase. Mechanical milling obviously increased the metallization degree compared with that of the standard pellet when reduced under the same conditions. Evolution of the mineral phase composition and microstructure of the reduced Ti–Nb-bearing Fe concentrate/coal composite pellet at 1100℃ were analyzed by X-ray diffraction and scanning electron microscopy–energy-dispersive spectroscopy. The volume shrinkage value of the reduced Ti–Nb-bearing Fe concentrate/coal composite pellet with a basicity of 1.0 was approximately 35.2% when the pellet was reduced at 1100℃ for 20 min, which enhanced the external heat transfer to the lower layers when reduced in a practical rotary hearth furnace. The present work provides key parameters and mechanism understanding for the development of carbothermic reduction technology of a Ti–Nb-bearing Fe concentrate incorporated in a pyrometallurgical utilization flow sheet.
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