Abstract: The pyrolysis process of cotton stalk was studied in nitrogen atmosphere by using the thermogravimetric analysis. The kinetic mechanism of the process was determined and corresponding kinetic parameters were calculated by double extrapolation method. Thermogravimetric analysis results show that the pyrolysis process can be divided into three stages: evolution of water (<150℃), devolatilization (200~400℃) and carbonization (>400℃). The kinetic analysis results show that Jander equation G(a)=[1-(1-a)1/3]2 and Z-L-T equation G(a)=[1/(1-a)1/3-1]2 are the most probable mechanism functions when the degree of conversion a is in the ranges of 0.15~0.4 and 0.7~0.9 respectively, which indicates that the primary pyrolysis process is three-dimensional diffusion.

Key words: double extrapolation method, cotton stalk, pyrolysis process, mechanism function

摘要： 利用热分析仪研究棉秆的热解过程，采用双外推法研究其动力学机理，并计算相应的热解动力学参数. 热重分析表明，棉秆热解过程可分为3个阶段：水分析出(<150℃)、脱挥发分(200~400℃)和炭化(>400℃). 动力学分析表明，Jander方程G(a)=[1-(1-a)1/3]2和Z-L-T方程G(a)=[1/(1-a)1/3-1]2分别是转化率a在0.15~0.4和0.7~0.9区间最可能的机理函数，其主要热解过程为三维扩散过程.

关键词: 双外推法, 棉秆, 热解过程, 机理函数