褐煤和秸秆生物质热解的热重教学实验设计

Experimental Design of Thermogravimetric Teaching Based on Coal and Biomass Pyrolysis

为了提升本科实验教学水平,将科学研究与实验教学相融合已成为目前实验课程改革的趋势。针对“煤化学与煤质分析”课程中学生难以理解煤炭的有机大分子结构特性及热转化机理的难题,设计了基于煤和生物质热解的热重教学实验。在TGA反应器中,对褐煤和秸秆生物质在10 K/min升温速率下,从室温到1100℃和大气压下进行热解实验。研究表明,因秸秆中含有较高的挥发分,生物质的失重率大于褐煤。随着热解温度升高,褐煤和秸秆生物质都经历了干燥脱吸阶段(室温~300℃)、主要热解阶段(300~600℃)和焦化阶段(高温900℃以上),但由于褐煤和秸秆生物质自身性质和组分的差异,其失重机理并不相同。通过此实验设计,可帮助学生更深入地理解和掌握煤炭的性质、用途及转化的原理与工艺;还可帮助学生了解生物质的热转化特性,提高学生的科研和学习兴趣。

In order to improve the level of undergraduate experimental teaching,the integration of scientific research and experimental teaching becomes the trend of experimental curriculum reform.Aiming at the problem that students have difficulty to understand organic macromolecules structural and thermal conversion mechanism of coal in the course of“Coal Chemistry and Coal Quality Analysis”,a thermogravimetric teaching experiment based on coal and biomass pyrolysis experiments is designed.In the TGA reactor,lignite and biomass are pyrolyzed at a heating rate of 10 K/min from room temperature to 1100℃and atmospheric pressure.It can be found that the weight loss rate of biomass is greater than that of lignite,since the biomass contains higher volatile matter.With the increase of pyrolysis temperature,lignite and biomass go out through the drying and desorption stage(room temperature~300℃),main pyrolysis stage(300~600℃)and coking stage(after high temperature 900℃).However,mechanisms of their weight loss are not the same,due to the differences in the properties and components of lignite and biomass.This experimental can help students to better understand and master the properties,utilizations,and transformation principles and processes of coal.It can also help students to understand the thermal transformation characteristics of biomass,and strengthen students’interest in scientific research and learning.