农林剩余物与钙基添加剂共热解/燃烧热重分析及其动力学研究
农林剩余物与钙基添加剂共热解/燃烧热重分析及其动力学研究(论文9000字)
摘要:农林剩余物是指在整个农业生产过程中主要产物之外的有机类物质,其可以通过热化学转化为燃料加以利用。本论文主要对比研究了三种农林剩余物生物质颗粒燃料(稻壳,草本残渣和木材残渣)与钙基添加剂(CaO,CaCO3和蛋壳)共热解和燃烧的热重分析及其动力学。在生物质的热解或燃烧过程中,钙基添加剂可以在相对较低的温度(如<400℃)下在脱挥发分阶段轻微地影响分解速率。然而,木质素分解和焦炭燃烧明显受到在较高温度(如>700℃)下的钙基催化作用的影响。值得注意的是,蛋壳在焦炭燃烧阶段具有最低的活化能。蛋壳中碱金属和碱土金属(AAEMs)的存在可能对挥发性和焦炭燃烧产生正面影响。在燃烧过程中,CaCO3和蛋壳的分解温度降低,从而有利于吸收CO2。此外,通过鉴定小分子产物,发现CaCO3和CaO均可改善稻壳的热解,但CaCO3表现出更好的性能,尤其是在较低温度下的提高了CO2捕获和CO产率。
关键词:热解;燃烧;农林业残留;钙添加剂;TGA;催化动力学
Thermogravimetric Analysis andKinetic Studies onCo-Pyrolysis and Co-Combustion of Agro-forestry Residues with Calcium-based Additives [来源:http://Doc163.com]
Abstract:The pyrolysis and combustion kinetics of biomass pellets (i.e., rice husk, herb residue, and wood residue) with the Calcium-based additives (i.e., CaO, CaCO3, and eggshell) from agro-forestry residues were comparatively studied. During pyrolysis or combustion of biomass, the calcium additives could slightly influence the decomposition rate in the stage of devolatilization at relatively lower temperatures (e.g., <400 oC). However, the lignin decomposition and the char combustion were obviously influenced by the calcium-based catalysis at higher temperatures (>700 oC). Particularly, the eggshell had a lowest activation energy in the stage of char combustion. The presence of alkali and alkaline-earth metals (AAEMs) in the eggshells might have positive effects on volatile and char combustion. During the combustion, the decomposition temperatures of CaCO3 and eggshell were decreased, thereby favoring to uptake CO2. Furthermore, by identifying the small molecular products, it was found that both CaCO3 and CaO can improve the pyrolysis of RH, but CaCO3 showed better performances, especially on CO2 capture at lower temperatures and on the enhancement of CO production. [版权所有:http://DOC163.com]
Keywords:Pyrolysis;Combustion;Agro-forestry residue;Calcium additive;TGA;Catalytic kinetic
目录
1.绪论 1
1.1.引言 1
1.2.国内外的研究进展 2
1.3.本研究目的和意义 2
1.4.技术路线图和研究内容 3
2.实验部分 4
2.1.农林废物来源与性质 4
2.2.热重分析实验 (热解/燃烧) 4
2.3.热重结果分析 5
2.3.仪器分析 5
3.结果与讨论 6
3.1.钙基添加剂表征 6
3.2.热解动力学分析 6
3.3.燃烧动力学分析 17
4.结论与展望 25
4.1.结论 25
4.2.展望 25
参考文献 25
[资料来源:http://www.doc163.com]
致谢 28
[来源:http://www.doc163.com]