Upgrading of Iron Concentrate by Fluidized-Bed Magnetizing Roasting of Siderite to Magnetite in CO–H2–N2 Atmosphere

  • Qiang Zhao
  • Jilai XueEmail author
  • Wen Chen
Technical Paper


Efficient use of abundant low-grade siderite ores can potentially mitigate the shortage of iron ore in the iron and steel industry in China. In this work, the beneficiation of siderite fines containing high levels of carbonates was studied using a combined fluidized-bed magnetizing roasting process. The siderite was almost completely converted into magnetite under the optimum conditions of preheating at 550 °C for 30 s followed by magnetizing roasting at 550 °C for 60 s at 0.5 m/s gas fluidization velocity in a 13.3% CO + 6.7% H2 + 80% N2 atmosphere. Magnetic separation was optimized using a fineness of that grind of 89.2% of the material passing 0.074 mm and magnetic field intensity 0.2 T. Comparative trials confirmed that the enhanced measures proposed, including optimizing gas fluidization velocity, preheating of the materials, the use of a mixed reducing gas, and selection of the optimum particle size of raw materials, could improve beneficiation of siderite. A high-grade magnetic concentrate containing 62.6 wt% iron grade with an iron recovery of 89.2% was achieved. The results demonstrated an effective process to utilize siderite ores.


Siderite Fluidized-bed magnetizing roasting Preheating Mixed reducing gas Particle size 



The authors wish to express their thanks to the Natural Science Foundation of China (No. 5157041410) for the financial support of this research.

Author’s Contribution

Qiang Zhao conducted the experimental work and prepared the manuscript; Jilai Xue directed the research work and modified the manuscript; Wen Chen participated in the design of the research work at different stages.

Compliance with Ethical Standards

Conflict of interest

The authors declare no conflict of interest.


  1. 1.
    Langman J B, and Moberly J G, J Geochem Explor 5 (2018) 185.CrossRefGoogle Scholar
  2. 2.
    Rasmussen B, and Muhling J R, Precambrian Res 3 (2017) 5.Google Scholar
  3. 3.
    Martin S, Toffolo L, Moroni M, Montorfano C, Secco L, Agnini C, Nimis P, and Tumiati S, Lithos 7 (2017) 276.CrossRefGoogle Scholar
  4. 4.
    Vusikhis A S, Leont’ev L I, Kudinov D Z, and Gulyakov V S, Russ Metall 5 (2016) 404.Google Scholar
  5. 5.
    Lima R D, and De Ros L F, Mar Pet Geol 9 (2002) 1049.Google Scholar
  6. 6.
    Yin W Z, Li D, Luo X M, Yao J, and Sun Q Y, Int J Miner Metall Mater 4 (2016) 374.Google Scholar
  7. 7.
    Yan H, Chai L Y, Peng B, Li M, Peng N, and Hou D K, Miner Eng 9 (2013) 103.Google Scholar
  8. 8.
    Hao H Q, Li L X, Yuan Z T, and Liu J T, J Mol Liq 254 (2018) 49.Google Scholar
  9. 9.
    Yu J W, Han Y X, Li Y J, Gao P, and Li W B, Minerals 11 (2017) 2.Google Scholar
  10. 10.
    Li C, Sun H H, and Bai J, J Hazard Mater 174 (2010) 71.CrossRefGoogle Scholar
  11. 11.
    Su Z J, Zhang Y B, and Chen J, Sep Sci Technol J 11 (2016) 1900.CrossRefGoogle Scholar
  12. 12.
    Chun T J, Zhu D Q, and Pan J, Miner Process Extr Metall Rev 36 (2015) 223.CrossRefGoogle Scholar
  13. 13.
    Zhang K, Chen X L, Guo W C, Luo H J, Gong Z J, Li B W, and Wu W F, Plos ONE 10 (2017)2.Google Scholar
  14. 14.
    Zhang Y H, Zhang J, Zhang Y J, Li H C, and Zhao P, J Wuhan Univ Technol 3 (2013) 116.Google Scholar
  15. 15.
    Yur’ev B P, and Gol’tsev V A, Ferr Metall 11 (2013) 3.Google Scholar
  16. 16.
    Yur’ev B P, Shatzillo V V, and Melamud S G, Ferr Metall 8 (2008)1.Google Scholar
  17. 17.
    Matyukhin V I, Melamud S G, Shatsillo V V, Matyukhin O V, and Matyukhina A V, Ferr Metall 9 (2015) 652.CrossRefGoogle Scholar
  18. 18.
    Matyukhin V I, Shatsillo V V, Kuznetsov A V, and Krokhalev A F, Metallurgist 1 (2017) 16.Google Scholar
  19. 19.
    Wang X H, Wang Z H, Liu J, Xiang F P, Zhou J H, and Cen K F, J Zhejiang Univ Eng Sci 4 (2013) 675.Google Scholar

Copyright information

© The Indian Institute of Metals - IIM 2019

Authors and Affiliations

  1. 1.School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijingChina
  2. 2.Changsha Research Institute of Mining and Metallurgy Co., LTDChangshaChina

Personalised recommendations