Non-isothermal combustion kinetics of two kinds of low volatile pulverized coals (HL coal and RU coal) were investigated by thermogravimetrie analysis. The results show that the combustibility of HL coal was better ...Non-isothermal combustion kinetics of two kinds of low volatile pulverized coals (HL coal and RU coal) were investigated by thermogravimetrie analysis. The results show that the combustibility of HL coal was better than that of RU coal, and with increasing heating rate, ignition and burnout characteristics of pulverized coal were improved. The volume model (VM), the random pore model (RPM), and the new model (NEWM) in which the whole combustion process is considered to be the overlapping process of volatile combustion and coal char combustion, were used to fit with the experimental data. The comparison of these three fitted results indicated that the combustion process of coal could be simulated by the NEWM with highest precision. When calculated by the NEWM, the activation energies of volatile combustion and coal char combustion are 130.5 and 95.7 kJ · mol^-1 for HL coal, respectively, while they are 114.5 and 147.6 kJ ·mol^-1 for RU coal, respectively.展开更多
目的分析生物质材料对塑料废弃物热降解的影响,以聚甲基丙烯酸甲酯(PMMA)为对象,探讨甘蔗渣对其热分解行为和动力学的作用。方法利用溶液共混法制备PMMA/甘蔗渣混合物,采用热失重法研究其在氮气中的热分解过程,通过最大失重速率法和Ozaw...目的分析生物质材料对塑料废弃物热降解的影响,以聚甲基丙烯酸甲酯(PMMA)为对象,探讨甘蔗渣对其热分解行为和动力学的作用。方法利用溶液共混法制备PMMA/甘蔗渣混合物,采用热失重法研究其在氮气中的热分解过程,通过最大失重速率法和Ozawa等失重法计算PMMA热分解反应的动力学参数活化能和频率因子。结果甘蔗渣使得PMMA的初期热分解温度明显降低,但是PMMA的热分解活化能和频率因子却都显著增加。最大失重速率法的计算结果表明,PMMA加入甘蔗渣后的热分解活化能增加了26.2 k J/mol,等失重法的结果显示活化能和频率因子分别为168.14 k J/mol和28.41 min-1,比纯PMMA相应地增大了72.6 k J/mol和12.52 min-1。结论甘蔗渣的加入对PMMA的热降解有显著的影响,使其热分解变得困难,因此有必要进一步探讨其他生物质对PMMA热分解的影响。展开更多
基金Item Sponsored by National Basic Research Program(973Program)of China(2012CB720401)National Key Technology Research and Development Program in the 12th Five-year Plan of China(2011BAC01B02)
文摘Non-isothermal combustion kinetics of two kinds of low volatile pulverized coals (HL coal and RU coal) were investigated by thermogravimetrie analysis. The results show that the combustibility of HL coal was better than that of RU coal, and with increasing heating rate, ignition and burnout characteristics of pulverized coal were improved. The volume model (VM), the random pore model (RPM), and the new model (NEWM) in which the whole combustion process is considered to be the overlapping process of volatile combustion and coal char combustion, were used to fit with the experimental data. The comparison of these three fitted results indicated that the combustion process of coal could be simulated by the NEWM with highest precision. When calculated by the NEWM, the activation energies of volatile combustion and coal char combustion are 130.5 and 95.7 kJ · mol^-1 for HL coal, respectively, while they are 114.5 and 147.6 kJ ·mol^-1 for RU coal, respectively.
文摘目的分析生物质材料对塑料废弃物热降解的影响,以聚甲基丙烯酸甲酯(PMMA)为对象,探讨甘蔗渣对其热分解行为和动力学的作用。方法利用溶液共混法制备PMMA/甘蔗渣混合物,采用热失重法研究其在氮气中的热分解过程,通过最大失重速率法和Ozawa等失重法计算PMMA热分解反应的动力学参数活化能和频率因子。结果甘蔗渣使得PMMA的初期热分解温度明显降低,但是PMMA的热分解活化能和频率因子却都显著增加。最大失重速率法的计算结果表明,PMMA加入甘蔗渣后的热分解活化能增加了26.2 k J/mol,等失重法的结果显示活化能和频率因子分别为168.14 k J/mol和28.41 min-1,比纯PMMA相应地增大了72.6 k J/mol和12.52 min-1。结论甘蔗渣的加入对PMMA的热降解有显著的影响,使其热分解变得困难,因此有必要进一步探讨其他生物质对PMMA热分解的影响。