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Effects of MgO additive on metallurgical properties of fluxed-pellet

MgO 添加剂对熔剂性球团矿冶金性能的影响

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Abstract

As a main charging burden of blast furnace (BF) ironmaking process, pellets play an important role in ironmaking process. However, compared with sinters, there are some inevitable disadvantages for traditional acid pellets, e.g., reduction swell, low melting temperature. Therefore, the fluxed-pellets have been applied in BF, especially MgO-fluxed pellets. In the present study, the effects of category and content of MgO bearing additive on the compressive strength (CS), reduction swelling index (RSI), reduction disintegration index (RDI) and melting-dripping properties of the pellets were investigated. Minerals composition, pore distribution and microstructure of MgO-flux pellets were studied by X-ray powder diffraction (XRD), mercury intrusion method and scanning electron microscopy (SEM), respectively. The results show that the light burned magnesite (LBM) is more suitable MgO bearing additive for fluxed-pellets. With increasing LBM content from 0 to 2.0%, the CS decreases from 3066 to 2689 N, RSI decreases from 16.43% to 9.97% and RDI decreases from 19.2% to 12.99%. The most appropriate MgO bearing additive content in the fluxed- pellets is 2.0% according to principal component analysis (PCA).

摘要

作为高炉炼铁重要原料, 球团矿在炼铁过程中起着重要作用. 然而, 与烧结矿相比, 传统的酸性球团矿存在不可避免缺点, 如还原膨胀、熔融温度低等. 因此, 熔剂型球团矿已经在高炉中广泛应用, 尤其是 MgO 熔剂型球团矿. 本文研究了MgO 添加剂种类和含量对球团矿抗压强度(CS)、 还原膨胀指数(RSI)、 还原粉化指数(RDI)和熔滴性能的影响; 采用了 X 射线衍射(XRD)、 压汞法和扫描电镜(SEM)研究了MgO 熔剂型球团矿矿物的组成、 孔分布和微观结构. 结果表明: 对于熔剂型球团矿, 轻烧菱镁石(LBM)是合适的含 MgO 添加剂. 随着 LBM 含量由 0% 增加到 2.0%, CS 由 3066 N 下降到 2689 N, RSI 由 16.43%下降到9.97%, RDI 由 19.2% 下降到12.99%。 基于主成分分析(PCA), 熔剂型球团矿中最合适的 MgO 添加剂含量为 2.0%.

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References

  1. [1]

    SHEN Feng-man, JIANG Xin, WU Gang-shen, WEI Guo, LI Xiao-gang, SHEN Yang-song. Proper MgO addition in blast furnace operation [J]. ISIJ International, 2006, 46(1): 65–69. DOI:https://doi.org/10.2355/isijinternational.46.65.

  2. [2]

    DWARAPUDI S, GHOSHT K, SHANKAR A, TATHAVADKAR V, BHATTACHARJEE D, VENUGOPAL R. Effect of pyroxenite flux on the quality and microstructure of hematite pellets [J]. International Journal of Mineral Processing, 2010, 96(1–4): 45–53. DOI: https://doi.org/10.1016/j.minpro.2010.06.002.

  3. [3]

    DWARAPUDI S, GHOSH T K, SHANKAR A, TATHAVADKAR V, BHATTACHARJEE D, VENUGOPAL R. Effect of pellet basicity and MgO content on the quality and microstructure of hematite pellets [J]. International Journal of Mineral Processing, 2011, 99(1): 43–53. DOI: https://doi.org/10.1016/j.minpro.2011.03.004.

  4. [4]

    DWARAPUDI S, GHOSH T K, TATHAVADKAR V, DENYS M B, BHATTACHARJEE D, VENUGOPAL R. Effect of MgO in the form of magnesite on the quality and microstructure of hematite pellets [J]. International Journal of Mineral Processing, 2012, 112–113(4): 55–62. DOI: https://doi.org/10.1016/j.minpro.2012.06.006.

  5. [5]

    FERREIRA S, CORES A, ROBLA J I, VERDEJA L F, RUIZ-BUSTINZA I, GARCIA-CARCEDO F, MOCHON J. The influence of gangue and additives on the divalent iron content of magnetite pellets [J]. Steel Research International, 2014, 85(2): 261–272. DOI: https://doi.org/10.1002/srin.201300370.

  6. [6]

    ILJANA M, KEMPPAINEN A, PAANANEN T, MATTILA O, PISILA E, KONDRAKOV M, FABRITIUS T. Effect of adding limestone on the metallurgical properties of iron ore pellets [J]. International Journal of Mineral Processing, 2015, 141: 34–43. DOI: https://doi.org/10.1016/j.minpro.2015.06.004.

  7. [7]

    MOUSA E, SENK D, BABICH A. Reduction of pellets-nut coke mixture under simulating blast furnace conditions [J]. Steel Research International, 2010, 81(9): 706–715. DOI: https://doi.org/10.1002/srin.201000047.

  8. [8]

    ZHU De-qing, MENDES V, CHUN Tie-jun, PAN Jian, LI Qi-hou, LI Jian, QIU Guan-zhou. Direct reduction behaviors of composite binder magnetite pellets in coal-based grate-rotary kiln process [J]. ISIJ International, 2011, 51(2): 214–219. DOI: https://doi.org/10.2355/isijinternational.51.214.

  9. [9]

    UMADEVI T, KUMAR P, LOBO N F, PRABHU M, MAHAPATRAP C, RANJAN M. Influence of pellet basicity (CaO/SiO2) on iron ore pellet properties and microstructure [J]. ISIJ International, 2011, 51(1): 14–20. DOI: https://doi.org/10.2355/isijinterna-tional.51.14.

  10. [10]

    UMADEVI T, LOBO N F, DESAI S, MAHAPATRA P C, SAH R, PRABHU M. Optimization of firing temperature for hematite pellets [J]. ISIJ International, 2013, 53(9): 1673–1682. DOI: https://doi.org/10.2355/isijinternational.53.1673.

  11. [11]

    FRIEL J J, ERICKSON E S. Chemistry, microstructure, and reduction characteristics of dolomite-fluxed magnetite pellets [J]. Matallurgical Transactions B, 1980, 11B(2): 233–243. DOI: https://doi.org/10.1007/BF02668407.

  12. [12]

    SUGIYAMA T, SHIROUCHI S, TSUCHIYA O, ONODA M, FUJITA I. Effect of Magnesite on the properties of pellets at room and low (900 °C) temperatures [J]. Transactions ISIJ, 1983, 23(2): 146–152. DOI: https://doi.org/10.2355/isijinternational1966.23.146.

  13. [13]

    SUGIYAMA T, SHIROUCHI S, TSUCHIYA O, ONODA M, FUJITA I. High temperature reduction and softening properties of pellets with magnesite [J]. ISIJ International, 2006, 23(2): 153–160. DOI: https://doi.org/10.2355/isijinternational1966.23.153.

  14. [14]

    LIU Zheng-gen, CHU Man-sheng, WANG Hong-tao, ZHAO Wei, XUE Xiang-xin. Effect of MgO content in sinter on the softening—melting behavior of mixed burden made from chromium-bearing vanadium—titanium magnetite [J]. International Journal of Minerals Metallurgy and Materials, 2016, 23(1): 25–32. DOI: https://doi.org/10.1007/s12613-016-1207-2.

  15. [15]

    LI Ting-le, SUN Chang-yu, LIU Xue-yan, SONG S, WANG Qi. The effects of MgO and Al2O3 behaviors on softening—melting properties of high basicitysinter [J]. Ironmaking & Steelmaking, 2018, 45(8): 755–763. DOI: https://doi.org/10.1080/03019233.2017.1337263.

  16. [16]

    SIVRIKAYA O, AROL A I. An investigation of the relationship between compressive strength and dust generation potential of magnetite pellets [J]. International Journal of Mineral Processing, 2013, 123(9): 158–164. DOI: https://doi.org/10.1016/j.minpro.2013.06.006.

  17. [17]

    GAO Qiang-jian, WEI Guo, SHEN Feng-man. Effect of MgO on compressive strength of pellet [J]. Journal of Northeastern Universuty, 2013, 34(1): 103–106. (in Chinese)

  18. [18]

    SURESH S. Fatigue of materials [M]. New York: Cambridge University Press, 1998.

  19. [19]

    GIBSON L J, ASHBY M F. Cellular solids structure and properties [M]. Cambridge: Cambridge University Press, 1997.

  20. [20]

    GAO Qiang-jian, JIANG Xin, WEI Guo, SHEN Feng-man. Characterization of consolidation degree of iron ore pellet by mercury injection method [J]. Journal of Northeastern University, 2013, 34(6): 832–835. (in Chinese)

  21. [21]

    DONSKOI E, MCELWAIN D L C. Mathematical modeling of non-isothermal reduction in highly swelling iron ore—coal char composite pellet [J]. Ironmaking & Steelmaking, 2013, 28(5): 384–389. DOI:https://doi.org/10.1179/030192301678244.

  22. [22]

    KUMAR M, NATH S, PATEL S K. Studies on the reduction-swelling behaviors of hematite iron ore pellets with noncokingcoal [J]. Mineral Processing and Extractive Metallurgy Review, 2010, 31(4): 256–268. DOI: https://doi.org/10.1080/08827508.2010.508826.

  23. [23]

    SINGH M, BJORKMAN B. Effect of reduction conditions on the swelling behaviour of cement-bonded briquettes [J]. ISIJ International, 2004, 44(2): 294–303. DOI: https://doi.org/10.2355/isijinternational.44.294.

  24. [24]

    XU Bin, HOU Tong, CHEN Xu-ling, LI Qian, JIANG Tao, LI Peng. Effect of dolomite on reduction swelling property of iron ore pellets [J]. Journal of Central South University, 2013, 20(10): 2806–2810. DOI: https://doi.org/10.1007/s11771-013-1800-8.

  25. [25]

    WANG Jian. Slag atlas [M]. 2nd ed. Verlag Stahleisen, GmbH, 1995: 63.

  26. [26]

    LI Wei, WANG Nan, FU Gui-qin, CHU Man-sheng, ZHU Miao-yong. Influence of TiO2 addition on the oxidation induration and reduction behavior of Hongge vanadium titanomagnetite pellets with simulated shaft furnace gases [J]. Powder Technology, 2018, 326: 137–145. DOI: https://doi.org/10.1016/j.powtec.2017.12.050.

  27. [27]

    LI Wei, WANG Nan, FU Gui-qin, CHU Man-sheng, ZHU Miao-yong. Influence of roasting characteristics on gas-based direct reduction behavior of Hongge vanadium titanomagnetite pellet with simulated shaft furnace gases [J]. Powder Technology, 2017, 310: 343–350. DOI: https://doi.org/10.1016/j.powtec.2017.01.062.

  28. [28]

    SESEN M K. The influence of CaO on the precipitation behaviour of iron in the reduction of iron oxide [J]. Scand J Metall, 2001, 30: 1–7.

  29. [29]

    ZHANG Han-quan, LU Man-man, FU Jin-tao. Oxidation and roasting characteristics of artificial magnetite pellets [J]. Journal of Central South University, 2016, 23(11): 2999–3005. DOI: https://doi.org/10.1007/s11771-016-3363-y.

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Acknowledgement

The authors wish to acknowledge the contributions of associates and colleagues in Northeastern University of China.

Author information

Correspondence to Xin Jiang 姜鑫.

Additional information

Foundation item: Projects(51874080, 51604069) supported by the National Natural Science Foundation of China; Project(N162504004) supported by the Fundamental Research Funds for the Central Universities, China

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Guo, H., Shen, F., Jiang, X. et al. Effects of MgO additive on metallurgical properties of fluxed-pellet. J. Cent. South Univ. 26, 3238–3251 (2019) doi:10.1007/s11771-019-4249-6

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Key words

  • pellets
  • MgO bearing additive
  • porosity
  • swelling
  • ironmaking
  • principal component analysis

关键词

  • 球团矿
  • MgO 添加剂
  • 气孔率
  • 膨胀性
  • 炼铁
  • 主成分分析