Research on the Recovery of Secondary Iron-Bearing Dust in Direct Reduction of Carbon Composite Pellets

Abstract:

In order to recover secondary iron-bearing dust, with converter sludge, mill scale, gravitational ash, casthouse ash as raw materials, high basicity carbon composite pellets are prepared to make iron nuggets through self-reduction at high temperature. The study demonstrates that: The effectively separation of iron and slag, naturally pulverization of the slag phase, and good surface quality of bigger, glosser and brighter iron nuggets can be obtained with reduction temperature 1400 °C,C/O molar ratio 1.1,as well as basicity above 1.8 in this process; The iron phase is not generated well and proportion of small size iron nuggets increases when C/O molar ratio is increased; With C/O molar ratio increases or temperature rises, CO generated increases in direct reduction, which strengthen the reducibility atmosphere in the pellets, beneficial to the processing of desulfuration and dephosphorization; Rising temperature accelerates the generation of molten iron, so that, the fixed carbon contacts with the molten iron longer, which increasing the carbon in iron nuggets. More carbon is provided for the carburizing reaction for the sake of increasing C/O molar ratio, as a result of making more carbon in iron nuggets.

• Periodical: Advanced Materials Research (Volumes 524-527)
• Pages: 2031-2036
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.524-527.2031
• Online since: May 2012
• Authors: Yi Shan Li, Zheng Liang Xue, En Tang, Qiang Liu, Wei Xiang Wang, Dong Nan Zhao
• Keywords: Carbon Composite Pellet, Direct Reduction, Secondary Iron-Bearing Dust, Self-Reduction

References

[1] Grant R T, Pargeter J K, Mac Dougall J A: MPT International, 1983 (4):20-24

[2] Hoffmange, Harada: Iron and Steelmaker, 1997, 24 (5):51-54

[3] Rene M, Jean B.D. S: MPT International, 1997(2):50-61

[4] I.Kobayashi, Y. Tanigaki and A. Uragami. Direct iron making process using fine ore and coal[C]. Asia Steel 2000, Vol.B, Beijing, 2000: 132-136

[5] Zhengliang Xue, Ligang Zhou, Haifeng Zhang, Guojun Ma, Lijia Wu: Journal of Wuhan University of Science and Technology, 2008, 31(50):453-456. (In Chinese)

[6] Haifeng Zhang, Zhengliang Xue, Jicheng Zhou: Journal of Wuhan University of Science and Technology, 2007, 30(2):125-127. (In Chinese)

[7] Dongnan Zhao, Zhengliang Xue, Die Yang et al: Revista Metalurgia International, 2011(7):10-14

[8] Zhengliang Xue, Die Yang, Ligang Zhou, Yingying Li: Journal of Wuhan University of Science and Technology, 2009, 32(1):1-4. (In Chinese)

[9] Zhengliang Xue, Dongnan Zhao, Die Yang, GuoJun Ma: Journal of University of Science and Technology Beijing, 2010, 32(12):25-31