Formation and characterization of metallic iron grains in coal-based reduction of oolitic iron ore

Yong-sheng Sun; Yue-xin Han; Yan-feng Li; Yan-jun Li

doi:10.1007/s12613-017-1386-5

Volume 24 Issue 2

Feb. 2017

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文章导航 > 矿物冶金与材料学报（英文） > 2017 > 24(2): 123-129

Yong-sheng Sun, Yue-xin Han, Yan-feng Li, and Yan-jun Li, Formation and characterization of metallic iron grains in coal-based reduction of oolitic iron ore, Int. J. Miner. Metall. Mater., 24(2017), No. 2, pp. 123-129. https://doi.org/10.1007/s12613-017-1386-5

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Yong-sheng Sun, Yue-xin Han, Yan-feng Li, and Yan-jun Li, Formation and characterization of metallic iron grains in coal-based reduction of oolitic iron ore, Int. J. Miner. Metall. Mater., 24(2017), No. 2, pp. 123-129. https://doi.org/10.1007/s12613-017-1386-5

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研究论文

Formation and characterization of metallic iron grains in coal-based reduction of oolitic iron ore

School of Resources and Civil Engineering, Northeastern University, Shenyang 110819, China

通讯作者:
Yong-sheng Sun E-mail: yongshengsun@mail.neu.edu.cn

中文摘要

To reveal the formation and characteristics of metallic iron grains in coal-based reduction, oolitic iron ore was isothermally reduced in various reduction times at various reduction temperatures. The microstructure and size of the metallic iron phase were investigated by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and a Bgrimm process mineralogy analyzer. In the results, the reduced Fe separates from the ore and forms metallic iron protuberances, and then the subsequent reduced Fe diffuses to the protuberances and grows into metallic iron grains. Most of the metallic iron grains exist in the quasi-spherical shape and inlaid in the slag matrix. The cumulative frequency of metallic iron grain size is markedly influenced by both reduction time and temperature. With increasing reduction temperature and time, the grain size of metallic iron obviously increases. According to the classical grain growth equation, the growth kinetic parameters, i.e., time exponent, growth activation energy, and pre-exponential constant, are estimated to be 1.3759 ±0.0374, 103.18 kJ·mol^-1, and 922.05, respectively. Using these calculated parameters, a growth model is established to describe the growth behavior of metallic iron grains.

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Research Article

Formation and characterization of metallic iron grains in coal-based reduction of oolitic iron ore

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Abstract

Abstract

To reveal the formation and characteristics of metallic iron grains in coal-based reduction, oolitic iron ore was isothermally reduced in various reduction times at various reduction temperatures. The microstructure and size of the metallic iron phase were investigated by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and a Bgrimm process mineralogy analyzer. In the results, the reduced Fe separates from the ore and forms metallic iron protuberances, and then the subsequent reduced Fe diffuses to the protuberances and grows into metallic iron grains. Most of the metallic iron grains exist in the quasi-spherical shape and inlaid in the slag matrix. The cumulative frequency of metallic iron grain size is markedly influenced by both reduction time and temperature. With increasing reduction temperature and time, the grain size of metallic iron obviously increases. According to the classical grain growth equation, the growth kinetic parameters, i.e., time exponent, growth activation energy, and pre-exponential constant, are estimated to be 1.3759 ±0.0374, 103.18 kJ·mol^-1, and 922.05, respectively. Using these calculated parameters, a growth model is established to describe the growth behavior of metallic iron grains.
- iron ore reduction;
- metallic iron;
- grain size;
- growth kinetics;
- activation energy

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[1]	S.X. Song, E.F. Campos-Toro, Y.M. Zhang, and A. Lopez-Valdivieso, Morphological and mineralogical characterizations of oolitic iron ore in the Exi region, China, Int. J. Miner. Metall. Mater., 20(2013), No. 2, p. 113.
[2]	W. Yu, T.C. Sun, Q. Cui, C.Y. Xu, and J. Kou, Effect of coal type on the reduction and magnetic separation of a high-phosphorus oolitic hematite ore, ISIJ Int., 55(2015), No. 3, p. 536.
[3]	Y.S. Sun, Y.X. Han, P. Gao, Z.H. Wang, and D.Z. Ren, Recovery of iron from high phosphorus oolitic iron ore using coal-based reduction followed by magnetic separation, Int. J. Miner. Metall. Mater., 20(2013), No. 5, p. 411.
[4]	M.J. Rao, C.Z. Ouyang, G.H. Li, S.H. Zhang, Y.B. Zhang, and T. Jiang, Behavior of phosphorus during the carbothermic reduction of phosphorus-rich oolitic hematite ore in the presence of Na₂SO₄, Int. J. Miner. Process., 143(2015), p. 72.
[5]	H.Q. Tang, T.F. Qi, and Y.Q. Qin, Production of low-phosphorus molten iron from high-phosphorus oolitic hematite using biomass char, JOM, 67(2015), No. 9, p. 1956.
[6]	J.T. Gao, L. Guo, and Z.C. Guo, Concentrating of iron, slag and apatite phases from high phosphorous iron ore gaseous reduction product at 1473 K by super gravity, ISIJ Int., 55(2015), No. 12, p. 2535.
[7]	W. Yu, T.C. Sun, Z.Z. Liu, J. Kou, and C.Y. Xu, Study on the strength of cold-bonded high-phosphorus oolitic hematite-coal composite briquettes, Int. J. Miner. Metall. Mater., 21(2014), No. 5, p. 423.
[8]	J. Kou, T. Sun, D. Tao, Y. Cao, and C. Xu, Coal-based direct reduction and magnetic separation of lump hematite ore, Miner. Metall. Process., 31(2014), No. 3, p. 150.
[9]	T.J. Chun, H.M. Long, and J.X. Li, Alumina-iron separation of high alumina iron ore by carbothermic reduction and magnetic separation, Sep. Sci. Technol., 50(2015), No. 5, p. 760.
[10]	U. Srivastava and S.K. Kawatra, Strategies for processing low-grade iron ore minerals, Miner. Process. Extr. Metall. Rev., 30(2009), No. 4, p. 361.
[11]	K.Q. Li, W. Ni, M. Zhu, M.J. Zheng, and Y. Li, Iron extraction from oolitic iron ore by a deep reduction process, J. Iron Steel Res. Int., 18(2011), No. 8, p. 9.
[12]	S.F. Li, Y.S. Sun, Y.X. Han, G.Q. Shi, and P. Gao, Fundamental research in utilization of an oolitic hematite by deep reduction, Adv. Mater. Res., 158(2011), p. 106.
[13]	W. Yu, T.C. Sun, Z.Z. Liu, J. Kou, and C.Y. Xu, Effects of particle sizes of iron ore and coal on the strength and reduction of high phosphorus oolitic hematite-coal composite briquettes, ISIJ Int., 54(2014), No. 1, p. 56.
[14]	G.H. Li, S.H. Zhang, M.J. Rao, Y.B. Zhang, and T. Jiang, Effects of sodium salts on reduction roasting and Fe-P separation of high-phosphorus oolitic hematite ore, Int. J. Miner. Process., 124(2013), p. 26.
[15]	W. Yu, T.C. Sun, J. Kou, Y.X. Wei, C.Y. Xu, and Z.Z. Liu, The function of Ca(OH)₂ and Na₂CO₃ as additive on the reduction of high-phosphorus oolitic hematite-coal mixed pellets, ISIJ Int., 53(2013), No. 3, p. 427.
[16]	C.Y. Xu, T.C. Sun, J. Kou, Y. Li, X. Mo, and L.G. Tang, Mechanism of phosphorus removal in beneficiation of high phosphorous oolitic hematite by direct reduction roasting with dephosphorization agent, Trans. Nonferrous Met. Soc. China, 22(2012), No. 11, p. 2806.
[17]	Y.S. Sun, Y.X. Han, P. Gao, and D.Z. Ren, Distribution behavior of phosphorus in the coal-based reduction of high-phosphorus-content oolitic iron ore, Int. J. Miner. Metall. Mater., 21(2014), No. 4, p. 331.
[18]	G.H. Li, M.J. Rao, C.Z. Ouyang, S.H. Zhang, Z.W. Peng, and T. Jiang, Distribution characteristics of phosphorus in the metallic iron during solid-state reductive roasting of oolitic hematite ore, ISIJ Int., (2015), No. 1, p. 1.
[19]	C. Cheng, Q.G. Xue, Y.Y. Zhang, F. Han, and J.S. Wang, Dynamic migration process and mechanism of phosphorus permeating into metallic iron with carburizing in coal-based direct reduction, ISIJ Int., 55(2015), No. 12, p. 2576.
[20]	J.W. Cha, D.Y. Kim, and S.M. Jung, Distribution behavior of phosphorus and metallization of iron oxide in carbothermic reduction of high-phosphorus iron ore, Metall. Mater. Trans. B, 46(2015), No. 5, p. 2165.
[21]	Y.S. Sun, Y.X. Han, P. Gao, and Y.F. Mu, Particle size measurement of metallic iron in reduced materials based on optical image analysis, Chem. Eng. Technol., 37(2014), No. 12, p. 2030.
[22]	Y.S. Sun, Y.X. Han, P. Gao, and J.W. Yu, Size distribution behavior of metallic iron particles in coal-based reduction products of an oolitic iron ore, Miner. Process. Extr. Metall. Rev., 36(2015), No. 4, p. 249.
[23]	Y.X. Han, Y.S. Sun, P. Gao, Y.J. Li, and Y.F. Mu, Particle size distribution of metallic iron during coal-based reduction of an oolitic iron ore, Miner. Metall. Process., 31(2014), No. 3, p. 169.
[24]	F. Chayes, On the bias of grain-size measurements made in thin section, J. Geol., 58(1950), No. 2, p. 156.
[25]	H. Hu and B.B. Rath, On the time exponent in isothermal grain growth, Metall. Trans., 1(1970), No. 11, p. 3181.
[26]	G.W. Yang, X.J. Sun, Q.L. Yong, Z.D. Li, and X.X. Li, Austenite grain refinement and isothermal growth behavior in a low carbon vanadium microalloyed steel, J. Iron Steel Res. Int., 21(2014), No. 8, p. 757.
[27]	S. Uhm, J. Moon, C. Lee, J. Yoon, and B. Lee, Prediction model for the austenite grain size in the coarse grained heat affected zone of Fe-C-Mn steels:Considering the effect of initial grain size on isothermal growth behavior, ISIJ Int., 44(2004), No. 7, p. 1230.
[28]	J. Reis and R. Chaim, Densification maps for spark plasma sintering of nanocrystalline MgO ceramics:Particle coarsening and grain growth effects, Mater. Sci. Eng. A, 491(2008), No. 1-2, p. 356.
[29]	R. Chaim, Densification mechanisms in spark plasma sintering of nanocrystalline ceramics, Mater. Sci. Eng. A, 443(2007), No. 1-2, p. 25.

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Formation and characterization of metallic iron grains in coal-based reduction of oolitic iron ore

中文摘要

Formation and characterization of metallic iron grains in coal-based reduction of oolitic iron ore

Abstract

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