N_(2)-CO-CO_(2)-H_(2)O气氛下K_((g))对焦炭高温气化反应动力学的影响  

Effect of K_((g))on high temperature gasification kinetics of coke in N_(2)-CO-CO_(2)-H_(2)O atmosphere

作　　者：兰臣臣 张淑会 刘然 吕庆 李福民 LAN Chen-chen;ZHANG Shu-hui;LIU Ran;LÜQing;LI Fu-min(College of Metallurgy and Energy,North China University of Science and Technology,Tangshan 063210,Hebei,China;Ministry of Education Key Laboratory of Modern Metallurgy Technology,North China University of Science and Technology,Tangshan 063210,Hebei,China)

机构地区：[1]华北理工大学冶金与能源学院,河北唐山063210 [2]华北理工大学教育部现代冶金技术重点实验室,河北唐山063210

出　　处：《中国冶金》2022年第7期12-19,共8页China Metallurgy

基　　金：河北省自然科学基金资助项目(E2021209046,E2019209424,E2020209208);唐山市科技计划资助项目(21130209C);河北省省属高等学校基本科研业务费资助项目(JQN_(2)021015)。

摘　　要：为了掌握高温区碱金属对焦炭气化过程的影响,在N_(2)-CO-CO_(2)-H_(2)O和N_(2)-CO-CO_(2)-H_(2)O-K_((g))气氛下,利用热失重法分别研究了焦炭在1413~1773 K的气化反应特征。结果显示,K_((g))对焦炭的气化反应具有较强的正催化作用,可以显著提高有效内扩散系数(D_(e))和界面反应速率常数(k_(+)),降低内扩散活化能与界面反应活化能,且K_((g))对内扩散的影响程度高于对界面反应的影响。随着反应率的增加,内扩散阻力(η_(i))和界面反应阻力(η_(C))均逐渐增加,K_((g))可以促进η_(i)和η_(C)降低。在N_(2)-CO-CO_(2)-H_(2)O气氛、1413 K时,气化反应的限制性环节逐渐由界面反应转为内扩散;而在1473、1573、1673和1773 K时其限制性环节始终为界面反应。在N_(2)-CO-CO_(2)-H_(2)O-K_((g))气氛下,气化反应的限制性环节始终为界面反应。In order to understand the influence of alkali metals in high temperature zone on coke gasification process,the kinetic behaviors of coke gasification in the temperature 1413-1773 K were studied by thermogravimetric analysis under atmospheres of N_(2)-CO-CO_(2)-H_(2)O and N_(2)-CO-CO_(2)-H_(2)O-K_((g)).The results show that K_((g))has a strong positive catalytic effect on the gasification reaction of coke,which can significantly improve the effective internal diffusion coefficient(D_(e))and interfacial reaction rate constant(k_(+)),reduce the activation energy of internal diffusion and interfacial reaction,and the influence of K_((g))on internal diffusion is higher than that on interfacial reaction.With increase of reaction rate,the internal diffusion resistance(η_(i))and interfacial reaction resistance(η_(C))increase gradually,whereas K_((g))tends to decrease η_(i) and η_(C).Under the N_(2)-CO-CO_(2)-H_(2)O atmosphere at 1413 K,the controlling factor gradually changes from interfacial reaction to internal diffusion.At 1473,1573,1673 and 1773 K,the controlling factor is always interface reaction.Under the N_(2)-CO-CO_(2)-H_(2)O-K_((g))atmosphere,the controlling factor is the interface reaction.

关 键 词：焦炭 气化 K_((g)) 反应阻力 限制性环节 

分 类 号：TF526.1[冶金工程—钢铁冶金]