基于傅里叶红外光谱的高温煤焦表面化学结构特性分析  

Chemical Structure Analysis of Coal Char Surface Based on Fourier-Transform Infrared Spectrometer

作　　者：李庆钊[1] 林柏泉[1] 赵长遂[2] 武卫芳[2] 

机构地区：[1]煤炭资源与安全开采国家重点实验室(中国矿业大学),江苏省徐州市221008 [2]东南大学能源与环境学院,江苏省南京市210096

出　　处：《中国电机工程学报》2011年第32期46-52,共7页Proceedings of the CSEE

基　　金：国家重点基础研究发展计划项目(973项目)(2006CB705806);中央高校基本科研业务费专项资金资助(2010QNA05);中国矿业大学人才引进资助项目;中国矿业大学青年教师启航计划资助项目~~

摘　　要：采用热力工况与实际煤粉炉相近的沉降炉,获取了不同环境气氛下的煤焦试样,采用傅里叶变化红外(Fourier-transform infrared,FTIR)光谱仪测定固体颗粒试样的表面微化学结构及官能团,通过FTIR谱图的分峰拟合处理,对焦样表面化学结构变化特征进行半定量分析。实验结果显示,热解及燃烧过程中所有的C—H、C—O类官能团基本均会随着挥发分一起析出,特别是含O及脂肪类结构基本消失,所属波段的吸收峰的强度均不同程度的有所减弱。无论热解还是燃烧过程,与芳氢相比煤焦中的脂肪类氢、碳基团更容易分解而析出,表现为试样中芳碳相对含量增加,焦样表观的芳香度(fa)升高。在高浓度的CO2气氛下,由于CO2对煤焦颗粒的气化效应,颗粒的实际温度较N2气氛时降低,使得煤焦中有机物的分解及析出过程有所延缓,表现为CO2气氛下颗粒的芳氢与脂氢比(Har/Hal)以及芳香度(fa)稍低于N2气氛时的情况。研究推断热解气氛及温度是影响有机组分分解及煤焦活性的关键因素。Coal char samples,partly burnt under different environments and temperatures,were prepared using a drop tube furnace with the combustion conditions similar to those in actual pulverized-coal boiler furnace.Micro structures and chemical groups of coal char surfaces were analyzed based on Fourier-transform infrared（FTIR） analyzer.Research results show that chemical structure such as C—H and C—O groups would be released combined with volatile matters emission during pyrolysis or combustion process.Especially for group contained O— and aliphatic structure,it would be eliminated clearly during thermal process,presented decreased FTIR spectrum peaks.Compared with aromatic groups,aliphatic structures would be decompounded easily,which caused increases of the relative contents of aromatic carbon and the aromaticity（fa） of thermal treated chars.For chars prepared under CO2 environments,the ratio of aromatic hydrogen and aliphatic hydrogen（Har/Hal） and aromaticity（fa） were always smaller than chars prepared in N2 environments.It can be concluded that thermal treated environments and temperature may be the key factors which effect chemical groups emission process and prepared chars reactivity.

关 键 词：O2/CO2气氛 煤焦 热解/燃烧 傅里叶红外 化学结构 

分 类 号：TQ534.9[化学工程—煤化学工程]