不同影响因素对煤焦气化特性的影响

Influence of Different Factors on Gasification Characteristics of Coal Char

为了消除内、外扩散对煤焦气化反应的影响,通过热重分析仪进行了3种煤焦的气化反应实验,气化剂为CO_(2)。研究了焦样粒径大小、焦样质量和气化剂流量对气化反应的影响,最终确定消除内、外扩散时的实验条件。此外还研究了气化温度对煤焦气化过程的影响。根据实验结果选取了3种动力学模型进行拟合,选取最适合描述气化反应的模型。结果表明:煤焦粒径对气化反应没有影响;随着煤焦质量减少,煤焦气化活性增加,但煤焦质量降低至一定值后气化活性不再变化;随着CO_(2)流量增加,煤焦气化活性增加,但CO_(2)流量增加至一定值后气化活性不再变化。混合反应模型最适合描述煤焦的气化反应过程。

In order to eliminate the influence of internal and external diffusion on the gasification reaction of coal char,the CO_(2)gasification reaction experiments of three kinds of coal char were carried out on the thermogravimetric experimental platform built by ourselves. The influence of coal char particle size, coke quality and CO_(2) gas flow rate on gasification process was studied, and the experimental conditions for eliminating internal and external diffusion were finally determined. In addition, the effect of gasification temperature on gasification reaction was also studied. According to the experimental results, three kinetic models were selected for fitting, and the most suitable model was selected to describe the gasification reaction. The results showed that, the particle size of coal char had no effect on gasification reaction;with the decrease of coke quality, the gasification activity of coal char increased, but the gasification activity did not change after the quality of coal char decreased to a certain value;with the increase of CO_(2)flow rate, the gasification activity of coal char increased, but the gasification activity did not change when the CO_(2) flow rate increased to a certain value;The mixed reaction model was most suitable to describe the gasification process of coal char.