Abstract

Thermogravimetry (TG) was used to obtain experimental data on the pyrolysis of sorghum biomass in an inert atmosphere at a heating rate of 3 K/min. Mathematical modeling of the process was carried out based on a three-component kinetic model. According to the model, biomass was represented by the sum of three components (hemicellulose, cellulose, and lignin), the pyrolysis of which proceeds according to independent parallel first-order reactions. To determine the kinetic parameters of the model, a step-by-step procedure based on difference in the temperature ranges of hemicellulose, cellulose, and lignin pyrolysis was proposed for experimental data processing. The kinetic parameters of first lignin, then cellulose, and finally hemicellulose were determined by recognizing and processing the corresponding fragments of TG data. The activation energies of pyrolysis of the biomass components were 25 kJ/mol for lignin, 105 kJ/mol for cellulose, and 30 kJ/mol for hemicellulose. The discrepancy between the experimental and calculated TG data in a temperature range above 440 K was 0.6%.

中文翻译：

---

基于三组分动力学模型的高粱生物质非等温热解数学建模

摘要

热重法 (TG) 用于获得高粱生物质在惰性气氛中以 3 K/min 的加热速率热解的实验数据。该过程的数学建模是基于三组分动力学模型进行的。根据该模型，生物质由三种成分（半纤维素、纤维素和木质素）的总和表示，其热解根据独立的平行一级反应进行。为了确定模型的动力学参数，提出了基于半纤维素、纤维素和木质素热解温度范围差异的分步程序进行实验数据处理。首先是木质素，然后是纤维素，最后是半纤维素的动力学参数是通过识别和处理相应的 TG 数据片段来确定的。生物质组分的热解活化能为木质素为 25 kJ/mol，纤维素为 105 kJ/mol，半纤维素为 30 kJ/mol。在高于 440 K 的温度范围内，实验和计算的 TG 数据之间的差异为 0.6%。