麦秆酶解残渣热解特性及动力学分析

对比分析了麦秆及其酶解残渣的基础物化特性，利用热重?红外联用技术研究了酶解残渣的热解反应过程及其主要气体产物的析出特性，并用混合反应模型计算了酶解残渣热解过程的表观动力学参数。结果表明，麦秆酶解残渣是一种富含木质素的高灰分、低热值的生物质原料，与麦秆原料相比，其热解过程相对平缓，主要失重温度区间为200℃ ~ 800℃，最大失重峰为350℃，与木质素的热解特性相近；提高升温速率可以使酶解残渣热解反应剩余产物质量明显减少，最大失重速率提高；热解主要气体产物中CH4析出的温度区间为400℃ ~ 700℃，CO和CO2在380℃、450℃和650℃都存在析出峰。动力学分析结果表明，酶解残渣热解过程在低温区（200℃ ~ 350℃）和高温区（350℃ ~ 800℃）分别遵循一级和二级反应动力学规律。

Pyrolysis and Kinetics Analysis of Wheat Straw Enzymolysis Residue

The physicochemical characteristics of wheat straw and its enzymolysis residue were analyzed, and then the pyrolysis behavior of the residue was investigated with TG-FTIR. Kinetic parameters were calculated based on a mixed reaction model. Analyses illustrated that the wheat straw residue was a kind of low heating value biomass fuel which was rich in inorganic compounds, and the main organic component was lignin. TG curves showed most weight-losing of the residue occurred during the temperature range of 200^oC ~ 800^oC. The rate of weight-losing reached the maximum at 350^oC. The pyrolysis process of the residue was similar to that of lignin and slower than that of wheat straw. It was also found that increase of heating rate resulted at higher reactivity and less remaining solid products. FTIR results showed that CH₄ released during 400^oC ~ 700^oC, and releasing peaks of CO and CO₂ occurred at temperature of 380^oC, 450^oC and 650^oC. It was first order reaction at the lower temperature range of 200^oC ~ 350^oC and second order reaction at the higher range of 350^oC ~ 800^oC.