Characteristics of combustion zone and evolution of mineral phases along bed height in ore sintering

Yao-zu Wang; Jian-liang Zhang; Zheng-jian Liu; Ya-peng Zhang; Dong-hui Liu; Yi-ran Liu

doi:10.1007/s12613-017-1499-x

Volume 24 Issue 10

Oct. 2017

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Article Navigation > International Journal of Minerals, Metallurgy and Materials > 2017 > 24(10): 1087-1095

Yao-zu Wang, Jian-liang Zhang, Zheng-jian Liu, Ya-peng Zhang, Dong-hui Liu, and Yi-ran Liu, Characteristics of combustion zone and evolution of mineral phases along bed height in ore sintering, Int. J. Miner. Metall. Mater., 24(2017), No. 10, pp. 1087-1095. https://doi.org/10.1007/s12613-017-1499-x

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Yao-zu Wang, Jian-liang Zhang, Zheng-jian Liu, Ya-peng Zhang, Dong-hui Liu, and Yi-ran Liu, Characteristics of combustion zone and evolution of mineral phases along bed height in ore sintering, Int. J. Miner. Metall. Mater., 24(2017), No. 10, pp. 1087-1095. https://doi.org/10.1007/s12613-017-1499-x

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Research ArticleOpen Access

Characteristics of combustion zone and evolution of mineral phases along bed height in ore sintering

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Received: 11 December 2016; Revised: 14 June 2017; Accepted: 15 June 2017

Abstract

Abstract

Quantitative parameters of bed combustion, including the thickness of the combustion zone (TCZ), the maximum temperature of the combustion zone (MTCZ), and the bed shrinkage, were characterized through a series of sinter pot tests in transparent quartz pots. The results showed that TCZ first ascended and then descended as the sintering process proceeded. The sintering process was divided into four stages according to the variation rate of the TCZ. A "relative-coordinate" method was developed to obtain the actual reaction temperature of sinter along the height direction. With increasing the sintering temperature, the reactants transformed and entered into liquid phases. The mineral composition and microstructure of the sinter were characterized through X-ray diffraction and scanning electron microscopy-energy-dispersive X-ray spectroscopy. Liquid phases with greater Fe and Al contents were more likely to form acicular-like silico-ferrite of calcium and aluminum after crystallization because of the outward spread of Al, which led to a better fluidity of the liquid. An evolution mechanism of "solid-state reaction-liquid phases formation-crystallization" of the mineral phases is proposed.
- flame front;
- mineral phases;
- sintering;
- evolution mechanism;
- transparent quartz pots

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