Effect of pressure and H2 on the pyrolysis characteristics of lignite: Thermal behavior and coal char structural properties
Effect of pressure and H2 on the pyrolysis characteristics of lignite: Thermal behavior and coal char structural properties
复制标题
压力和氢气对褐煤热解特性的影响：热行为和煤焦结构特性
DOI：
10.1016/j.jaap.2018.10.003
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发表时间：
2018-10-01
影响因子：
6
通讯作者：
Thallada, Bhaskar
中科院分区：
文献类型：
--
作者：
Wang, Guijin;Hou, Baolin;Thallada, Bhaskar
研究了压力和氢气对褐煤热解特性的影响。采用加压热重分析仪（P-TGA）研究了褐煤在不同Ar或H2压力下的热解行为。采用元素分析仪、傅里叶变换红外光谱仪、X射线衍射仪、气体吸附比表面积和孔径分析仪等分析手段，研究了热解煤焦的结构特征。用热重分析（TGA）评价了煤焦的CO2气化反应活性。实验结果表明，褐煤在氢气存在下热解失重率增大，且随压力的升高而增大。同时，加压加氢热解过程中的C和H转化率也得到了显著提高。煤焦的芳香性和石墨化度均随H2的加入而增强，特别是在高压下。在中孔结构方面，加氢热解煤焦的BET比表面积比Ar气氛下煤焦的大，特别是加压条件下的大。此外，加氢热解煤焦表现出较高的CO2气化反应活性。
The aim of the present work was to investigate the effect of pressure and H-2 on the pyrolysis characteristics of lignite. Thermogravimetric behavior during lignite pyrolysis was studied under different Ar or H-2 pressures using a pressurized thermogravimetric analyzer (P-TGA). Structural properties of coal chars obtained from P-TGA were investigated by the application of elemental analyzer, Fourier transform infrared spectroscopy, X-ray diffraction analyzer, and gas sorption surface area and pore size analyzer. CO2 gasification reactivity of coal chars was also evaluated by TGA tests. The results demonstrated that the weight loss for lignite pyrolysis increased in the presence of H-2 and it became more remarkable with rising pressure. Meanwhile, conversion of C and H during pressurized hydropyrolysis was promoted to a higher level considerably. Aromaticity as well as graphitization degree for coal chars were both intensified with addition of H-2, especially under elevated pressures. As to the mesopore structure, BET specific surface area of coal chars from hydropyrolysis increased obviously in comparison with that of coal chars obtained in Ar atmosphere, especially under pressurized conditions. Moreover, coal chars from hydropyrolysis exhibited higher CO2 gasification reactivity.