玉米秸秆热解动力学分析

Kinetic analysis of cornstalk pyrolysis

该文采用耐驰STA449同步热分析仪,研究了玉米秸秆在升温速率为5、10、15、20、30 K/min,反应终止温度1273K的热分解反应, 结果表明玉米秸秆热解过程可分为失水预热解、热解和碳化3个阶段,随着升温速率增加,反应的特征温度和最大失重速率增加,差示扫描(DSC) 曲线整体向下倾斜,升温速率过大时,出现失水滞后现象。分别用FWO法、FRL法和Kissinger法对玉米秸秆热解进行了动力学计算,其热解活化能为(161±23)kJ/mol,通过Malek法确定了玉米秸秆热解满足J-M-A方程,反应机理为随机成核随后生长,确定了反应级数n和指前因子对数lgA的范围,并利用Matlab软件对实验数据进行拟合,验证了机理的正确性,并确定了玉米秸秆热解反应的动力学参数。该文结果对工程应用有指导意义。

Pyrolysis of cornstalk was studied by using STA449c thermogravimetric apparatus with the heating rates of 5,10,15,20,30 K/min and final temperature of 1273 K.The pyrolysis process of cornstalk includes three steps:losing water and pre-pyrolysis,main pyrolysis and carbonization.As the heating rate increased,the maximum pyrolysis rate increased greatly,and the characteristic temperature became higher and the DSC curves sloped down.When heating rate was too fast,dehydration process was lagged behind.The activa...