Effect of internal diffusion on steam gasification reactivity of coal and petroleum coke
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摘要: 以内蒙褐煤、神府烟煤、遵义无烟煤和石油焦为研究对象,借助热重分析仪,进行了水蒸气气化动力学研究,得到了4种样品焦的本征动力学方程,分析了水蒸气分压和粒径对气化反应的影响。基于幂函数模型得到的动力学参数,结合气固催化理论,提出了计算内扩散效率因子(η)的方法。计算效率因子(ηcal)和实验效率因子(ηexp)的对比结果表明,使用该方法得到的内扩散效率因子可以用于定量评估水蒸气气化反应中内扩散过程的影响程度。Abstract: The steam gasification experiments with Neimeng lignite, Shenfu bituminous coal, Zunyi anthracite and a petroleum coke were conducted in a thermogravimetric analyzer (TGA) to study the intrinsic kinetics and the macrokinetics with the effects of particle size. By virtue of gas-solid catalysis theory, a method to calculate the internal effective factor was proposed based on the kinetic parameters derived from the nth-order equation. The comparison between calculated and experimental effective factors shows that the method is better to calculate the internal effective factor for quantificationally estimating the effect of internal diffusion on steam gasifiation.
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Key words:
- gasification reactivity /
- steam /
- internal diffusion /
- Thiele modulus /
- effective factor
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