In situ observation of reduction kinetics and 2D mapping of chemical state for heterogeneous reduction in iron-ore sinters

16th International Conference on X-ray Absorption Fine Structure

Kimura, M.^1,2,3 ; Murao, R.^3 ; Ohta, N.^4 ; Noami, K.^4 ; Uemura, Y.^1 ; Niwa, Y.^1 ; Kimijima, K.^1 ; Takeichi, Y.^1,2 ; Nitani, H.^1,2

Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki

305-0801, Japan^1

Department of Materials Structure Science, School of High Energy Accelerator Science, SOKENDAI (The Graduate University for Advanced Studies), Tsukuba, Ibaraki

305-0801, Japan^2

Advanced Technology Research Laboratories, Nippon Steel and Sumitomo Metal Co., Chiba

293-8511, Japan^3

Nippon Steel and Sumikin Technology Co. Ltd., Chiba

293-0011, Japan^4

关键词: Absorption fine structure;    Calcium ferrite;    Heterogeneous distributions;    Heterogeneous reduction;    In-situ observations;    Reduction kinetics;    Two dimensional mapping;    X ray fluorescence;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/712/1/012077/pdf
DOI  :  10.1088/1742-6596/712/1/012077

来源: IOP

【 摘 要 】

Iron-ore sinters constitute the major component of the iron-bearing burden in blast furnaces, and the mechanism of their reduction is one of the key processes in iron making. The heterogeneous reduction of sintered oxides was investigated by the combination of X-ray fluorescence and absorption fine structure, X-ray diffraction, and computed tomography. Two - dimensional mapping of the chemical states (CSs) was performed. The iron CSs FeIII, FeII, and Fe0exhibited a heterogeneous distribution in a reduced sinter. The reduction started near micro pores, at iron-oxide grains rather than calcium-ferrite ones. The heterogeneous reduction among grains in a sinter may cause the formation of micro cracks. These results provide fundamental insights into heterogeneous reduction schemes for iron-ore sinters.