文献类型：期刊文献

英文题名：Diffusion effect and evolution of kinetic parameters during coal char-CO2 gasification

作者：Meng, Dexi[1];Wang, Tian[1];Xu, Jianliang[1];Chen, Xueli[1]

机构：[1]East China Univ Sci & Technol, Shanghai Engn Res Ctr Coal Gasificat, POB 272, Shanghai 200237, Peoples R China

年份：2019

卷号：255

外文期刊名：FUEL

收录：;EI(收录号：20193107253350);WOS:【SCI-EXPANDED(收录号:WOS:000479141700036)】；

基金：This work was supported by the National Key Research and Development Project of China (2016YFB0600400), the Fundamental Research Funds for the Central Universities, China 222201718003).

语种：英文

外文关键词：Coal char gasification; Diffusion effect; Effectiveness factor; Kinetic parameters; Compensation effect

摘要：Large coal char particle (LCC, 12mm and 20mm cube) and small coal char particle (SCC, less than 50 mu m) were gasified under different temperatures in fixed bed reactor and thermogravimetric analyzer, respectively. The effectiveness factor and kinetic parameters (apparent activation energy and apparent pre-exponential factor) were also calculated to investigate the diffusion effect and the evolution of kinetic parameters during coal char-CO2 gasification. It was found that the internal effectiveness factor was not constant during the conversion process of coal char. In the intermediate and later stage of gasification reaction, there was a remarkable increase for the effectiveness factor. The effectiveness factor of LCC and SCC in the higher temperature range were all much less than 1, this indicated that the gasification of LCC and SCC at high temperature was limited by pore diffusion. Apparent activation energy and apparent pre-exponential factor evolved gradually during the whole conversion process, the existence of diffusion effect would lead to a certain change for the evolution law. A kinetic compensation effect was observed between the apparent activation energy and apparent pre-exponential factor during the conversion process of coal char. When the diffusion effect was very significant, it would have a certain weakening effect on the compensation effect.