煤粉与半焦的混合燃烧特性及动力学分析  

Combustion characteristics and kinetic analysis of pulverized coal and semicoke

作　　者：巢昌耀 吴铿[1] 杜瑞岭[1] 张黎[1] 徐大安 朱春恩 

机构地区：[1]北京科技大学钢铁冶金新技术国家重点实验室,北京100083

出　　处：《工程科学学报》2016年第11期1532-1538,共7页Chinese Journal of Engineering

基　　金：国家自然科学基金资助项目(51274026);榆林市科技计划资助项目(2014cxy-06);陕西省自然科学基础研究基金面上资助项目(2016JM5028)

摘　　要：为探究煤粉添加半焦后混合燃料的燃烧性能,通过热重分析研究煤、半焦及其混合物的燃烧过程,得到燃烧特性参数.由于不同温度区间的燃烧反应机理不同,利用分段法对燃烧过程进行动力学分析,对燃烧反应的前、后期分别使用缩核反应模型和缩核内扩散模型进行模拟,从而得到动力学参数.结果显示,随着混合燃料中半焦含量增加,其可燃性指数和燃烧特性指数都减少,燃烧前期活化能由76.79 k J·mol^(-1)增加到92.75 k J·mol^(-1),后期活化能由102.62 k J·mol^(-1)增加到107.94k J·mol^(-1),说明半焦的添加会降低混合燃料的燃烧性能.对比不同半焦含量的混合燃料的燃烧特性参数和动力学参数,半焦的质量分数应控制在15%以内最适宜.To explore the combustion performance of blended fuels after adding semicoke, the combustion processes of coal, semieoke, and their mixture were studied by thermogravimetric analysis （TGA） and the combustion characteristic parameters were obtained. Due to the different mechanisms in different temperature ranges of combustion reaction, the kinetics of the combustion process was analyzed by the sectioning method, and the shrinking core models of interracial chemical reaction and internal diffusion were used to model the process at the earlier stage and the later stage to obtain the kinetic parameters, respectively. The results show that with increasing semicoke content in blended fuels, the ignition index and the combustion characteristic index decrease, and the combustion activation energy of blended fuels increases from 76. 79 kJ· mol- 1 to 92. 75 kJ·mol- l at the earlier stage and from 102. 62 kJ· mol-1 to 107.94 kJ·mol- 1 at the later stage. It is demonstrated that the combustion performance of blended fuel deteriorates with the increasing semicoke content. By comparing the combustion characteristic parameters and kinetic parameters of blended fuels with different semicoke contents, the mass fraction of semicoke should be controlled below 15%.

关 键 词：高炉 燃料 半焦 煤粉 燃烧 动力学分析 

分 类 号：TF053[冶金工程—冶金物理化学]