采用单纯形格子混合设计法(SLMD)对纤维素、半纤维素和木质素3种生物质组分进行复配优化设计,并在综合热分析仪上进行了热解试验。分析了3组分混合热解特性,建立了由生物质3组分比例直接计算动力学参数的预测模型,对模型进行了试验验证...采用单纯形格子混合设计法(SLMD)对纤维素、半纤维素和木质素3种生物质组分进行复配优化设计,并在综合热分析仪上进行了热解试验。分析了3组分混合热解特性,建立了由生物质3组分比例直接计算动力学参数的预测模型,对模型进行了试验验证。结果表明:纤维素热解反应级数较低(1.20),活化能较高(134.50 k J/mol),指前因子较大(3.49×1012s-1),热解较为迅速与剧烈;半纤维素和木质素热解的反应级数较高(1.30、1.32),活化能较低(33.51、19.98 k J/mol),指前因子较小(9.43×103、107 s-1),热解较为缓慢;3组分在混合热解中对动力学参数存在交互影响,纤维素对活化能和指前因子的影响较为显著,而半纤维素与木质素对反应级数的影响较大;动力学参数预测模型精度较高,可有效预测生物质热解动力学参数。展开更多
The aim of this study is to determine the effect of the main chemical components ofbiomass： cellulose, hemicel- lulose and lignin, on chemical kinetics ofbiomass pyrolysis. The experiments were designed based on a si...The aim of this study is to determine the effect of the main chemical components ofbiomass： cellulose, hemicel- lulose and lignin, on chemical kinetics ofbiomass pyrolysis. The experiments were designed based on a simplex- lattice mixture design. The pyrolysis was observed by using a thermogravimetric analyzer. The curves obtained from the employed analytical method fit the experimental data （R2 〉 0.9）. This indicated that this method has the potential to determine the kinetic parameters such as the activation energy （E~）, frequency factor （A） and re- action order （n） for each point of the experimental design. The results obtained from the simplex-lattice mixture design indicated that cellulose had a significant effect on Ea and A, and the interaction between cellulose and lignin had an important effect on the reaction order, n. The proposed models were then proved to be useful for predicting pyrolysis behavior in real biomass and so could be used as a simple approximation for predicting the overall trend of chemical reaction kinetics.展开更多
文摘采用单纯形格子混合设计法(SLMD)对纤维素、半纤维素和木质素3种生物质组分进行复配优化设计,并在综合热分析仪上进行了热解试验。分析了3组分混合热解特性,建立了由生物质3组分比例直接计算动力学参数的预测模型,对模型进行了试验验证。结果表明:纤维素热解反应级数较低(1.20),活化能较高(134.50 k J/mol),指前因子较大(3.49×1012s-1),热解较为迅速与剧烈;半纤维素和木质素热解的反应级数较高(1.30、1.32),活化能较低(33.51、19.98 k J/mol),指前因子较小(9.43×103、107 s-1),热解较为缓慢;3组分在混合热解中对动力学参数存在交互影响,纤维素对活化能和指前因子的影响较为显著,而半纤维素与木质素对反应级数的影响较大;动力学参数预测模型精度较高,可有效预测生物质热解动力学参数。
基金Supported by the Grants from the Thailand Research Fund for fiscal year 2014–2016(TRG5780205)the Grant for Development of New Faculty Staff(Ratchadaphisek Somphot Endowment Fund)of Chulalongkorn Universitythe Center of Excellence on Petrochemical and Materials Technology,Chulalongkorn University
文摘The aim of this study is to determine the effect of the main chemical components ofbiomass： cellulose, hemicel- lulose and lignin, on chemical kinetics ofbiomass pyrolysis. The experiments were designed based on a simplex- lattice mixture design. The pyrolysis was observed by using a thermogravimetric analyzer. The curves obtained from the employed analytical method fit the experimental data （R2 〉 0.9）. This indicated that this method has the potential to determine the kinetic parameters such as the activation energy （E~）, frequency factor （A） and re- action order （n） for each point of the experimental design. The results obtained from the simplex-lattice mixture design indicated that cellulose had a significant effect on Ea and A, and the interaction between cellulose and lignin had an important effect on the reaction order, n. The proposed models were then proved to be useful for predicting pyrolysis behavior in real biomass and so could be used as a simple approximation for predicting the overall trend of chemical reaction kinetics.
