Effects of H2O Gasification Reaction on the Characteristics of Chars under Oxy-Fuel Combustion Conditions with Wet Recycle
Effects of H2O Gasification Reaction on the Characteristics of Chars under Oxy-Fuel Combustion Conditions with Wet Recycle
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湿式循环富氧燃烧条件下H2O气化反应对炭特性的影响
DOI：
10.1021/acs.energyfuels.6b01725
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发表时间：
2016
期刊：
影响因子：
5.3
通讯作者：
Xiang Jun
中科院分区：
文献类型：
--
作者：
Xu Jun;Su Sheng;Sun Zhijun;Si Ningning;Qing Mengxia;Liu Lijun;Hu Song;Wang Yi;Xiang Jun
本工作旨在阐明湿循环富氧燃烧条件下，H2O气化反应对焦炭特性的潜在影响。在1350K的流态化/固定床反应器中，分别在CO2/N_2、H_2O/N_2和CO_2/H_2O气氛下制备了中国亚烟煤的半焦。利用显微拉曼光谱仪、傅里叶变换红外光谱仪和氮气吸附技术对焦炭的结构进行了表征。用热重分析仪测定了焦炭的燃烧反应性，揭示了富氧燃烧中结构变化对焦炭燃烧反应性的影响。结果表明，CO2/H2O中确实存在H2O气化反应，并加速了焦炭的消耗，但其影响程度低于H2O/N2中。随着CO2/H2O中H2O浓度的增加，H2O气化反应会影响半焦的化学结构，并观察到不同的气化现象。
This work aims to clarify the potential effects of the H2O gasification reaction on the characteristics of chars under oxy-fuel combustion conditions with wet recycle. Chars of a Chinese sub-bituminous coal were prepared in a fluidized-bed/fixed-bed reactor at 1350 K under CO2/N2, H2O/N2, and CO2/H2O atmospheres. Structures of the chars undergoing some extent of gasification were characterized with a micro-Raman spectrometer, Fourier transform infrared spectrometer, and the N2 adsorption technique. Char combustion reactivity was also obtained in a thermogravimetric analyzer to reveal the effects of structure changes on the char combustion reactivity in oxy-fuel combustion. The results indicate the H2O gasification reaction can really take place and accelerate the char consumption in CO2/H2O, but the effect extent is lower than that in H2O/N2. The H2O gasification reaction would affect the chemical structures of the char with increasing H2O concentration in CO2/H2O, and different phenomena are observed for...