In this paper, kinetic modelling of carbothermal reduction reaction rates of coal and analytically pure silica at different temperatures, coal types and coal particle sizes is investigated. On the basis of the kinetic model, the coal was structurally scanned by an industrial CT scanner, and the data was analyzed using the analytical software Avizo. The reactivity of coal was strongly correlated with porosity and weakly correlated with pore size distribution and sphericity. Kinetic modelling of coal and analytically pure silica at temperatures of 1898 K (1625℃), 1923 K (1650℃) and 1948 K (1675℃) was investigated. The entire SiC generation reaction can be described by the reaction SiO2 + 3C = SiC + 2CO. The reaction rates of silica and coal in the SiC production step can be expressed as <InlineEquation ID="IEq1"> <EquationSource Format="TEX">$\frac{d\eta}{dt}=\left(1-0.47\times X_{fix-C}^{-0.92}\times F_C\times\eta\right)\times A\times exp\left(-\frac E{RT}\right)$</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mfrac> <mrow> <mi>d</mi> <mi>η</mi> </mrow> <mrow> <mi mathvariant="italic">dt</mi> </mrow> </mfrac> <mo>=</mo> <mfenced close=")" open="("> <mn>1</mn> <mo>-</mo> <mn>0.47</mn> <mo>×</mo> <msubsup> <mi>X</mi> <mrow> <mi>f</mi> <mi>i</mi> <mi>x</mi> <mo>-</mo> <mi>C</mi> </mrow> <mrow> <mo>-</mo> <mn>0.92</mn> </mrow> </msubsup> <mo>×</mo> <msub> <mi>F</mi> <mi>C</mi> </msub> <mo>×</mo> <mi>η</mi> </mfenced> <mo>×</mo> <mi>A</mi> <mo>×</mo> <mi>e</mi> <mi>x</mi> <mi>p</mi> <mfenced close=")" open="("> <mo>-</mo> <mfrac> <mi>E</mi> <mrow> <mi mathvariant="italic">RT</mi> </mrow> </mfrac> </mfenced> </mrow> </math></EquationSource> </InlineEquation>. The carbon factor <InlineEquation ID="IEq2"> <EquationSource Format="TEX">${F}_{C}$</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>F</mi> <mi>C</mi> </msub> </math></EquationSource> </InlineEquation> of the four coals was used to describe the effect of different carbon materials on the gas–solid interfacial reaction. The carbon factor was 0.9985 for C1 coal, 1.0288 for C2 coal, 1.0188 for C3 coal, and 1.0141 for C4 coal. The fingering factors for the four coals were 2.91E + 09 min−1, 4.37E + 10 min−1, 1.08E + 10 min−1, and 3.91E + 08 min−1. For C1-C4 pellets, the activation energies E of the SiC production step were 304 kJ/mol, 355 kJ/mol, 326 kJ/mol, and 271 kJ/mol, respectively.

Kinetic Study of Silica Reduction by different Coals

期刊论文
发表日期：

2026年2月1日

查看全文

Fei Li,
YuXuan Kang,
KaiXin Yang

摘要

In this paper, kinetic modelling of carbothermal reduction reaction rates of coal and analytically pure silica at different temperatures, coal types and coal particle sizes is investigated. On the basis of the kinetic model, the coal was structurally scanned by an industrial CT scanner, and the data was analyzed using the analytical software Avizo. The reactivity of coal was strongly correlated with porosity and weakly correlated with pore size distribution and sphericity. Kinetic modelling of coal and analytically pure silica at temperatures of 1898 K (1625℃), 1923 K (1650℃) and 1948 K (1675℃) was investigated. The entire SiC generation reaction can be described by the reaction SiO₂ + 3C = SiC + 2CO. The reaction rates of silica and coal in the SiC production step can be expressed as $\frac{d\eta}{dt}=\left(1-0.47\times X_{fix-C}^{-0.92}\times F_C\times\eta\right)\times A\times exp\left(-\frac E{RT}\right)$ $\frac{d η}{dt} = (1 - 0.47 \times X_{f i x - C}^{- 0.92} \times F_{C} \times η) \times A \times e x p (- \frac{E}{RT})$ . The carbon factor ${F}_{C}$ $F_{C}$ of the four coals was used to describe the effect of different carbon materials on the gas–solid interfacial reaction. The carbon factor was 0.9985 for C1 coal, 1.0288 for C2 coal, 1.0188 for C3 coal, and 1.0141 for C4 coal. The fingering factors for the four coals were 2.91E + 09 min⁻¹, 4.37E + 10 min⁻¹, 1.08E + 10 min⁻¹, and 3.91E + 08 min⁻¹. For C1-C4 pellets, the activation energies E of the SiC production step were 304 kJ/mol, 355 kJ/mol, 326 kJ/mol, and 271 kJ/mol, respectively.