摘要
本文采用化学方法测定了六种生物质中纤维素和木质素的含量,通过热重研究了实际生物质及用纤维素、木质素按一定比例混合模拟生物质的热解和气化特性,并结合电子扫描电镜(SEM)对焦样进行了微观形貌分析.结果表明:在本文所选择的生物质中纤维素的含量高于木质素,两者一般在55%～85%和10%～35%.生物质热解分为纤维素热解和木质素分解两个阶段,对应于气化过程中挥发份析出和焦炭气化.在热解过程中,首先纤维素发生热解呈现快速失重过程,接着木质素缓慢热解.实验发现生物质中纤维素含量越高,热解反应速率就越大;反之,木质素含量越高.热解反应速率越小.通过对焦形貌与气化研究,发现气化特性与生物质中纤维素和木质素的含量有着密切联系.因此纤维素、木质素含量是影响生物质热解气化特性的重要因素之一.
First of all, the cellulose and lignin contents in six biomass fuels were analyzed chemically. In this study, the cellulose content was higher than that of lignin for the biomass samples selected. The cellulose and lignin contents varied from 55% to 85% and from 10% to 35%, respectively. Fundamental pyrolysis behavior of cellulose, lignin and biomass were investigated by an athermo-gravimetric analyzer. The pyrolysis process for the real biomass samples might be classified into two stages. The first stage showed rapid mass decrease caused by cellulose pyrolysis. While the second stage corresponded to the decomposition of lignin. For the biomass with higher cellulose content, it had a faster pyrolysis rate. In contrast, the biomass with higher lignin content showed slower pyrolysis rate. At the same time, the gasification behavior of biomass was strongly relevant to the cellulose and lignin contents of biomass. Therefore, The experimental results showed that the cellulose and lignin contents in the biomass fuels were important parameters to evaluate their pyrolysis and gasification characteristics.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2008年第10期1771-1774,共4页
Journal of Engineering Thermophysics
基金
教育部科学技术研究重点资助项目(No.107074)
国家自然科学基金(No.50721005
No.50325621)
关键词
生物质
纤维素
木质素
热解
气化
biomass
cellulose
lignin
pyrolysis
gasification
