垃圾填埋气部分氧化重整制合成气的热力学分析

Thermodynamic analysis for syngas production via landfill gas partial reforming

采用吉布斯自由能最小法对垃圾填埋气(简化为甲烷与二氧化碳混合物)部分氧化重整制合成气进行了热力学分析,得出了生成适于费托反应的合成气组分的最适反应条件。结果显示:当反应温度大于1 073 K时,CH_4转化率大于99%,反应生成的气体中CH_4的含量小于0.25%。分别提高反应温度和O_2/CH_4摩尔比均有助于抑制积炭的生成。反应生成的气体中,H_2和CO分别达到最大值时,所对应的反应条件的范围不同,但在特定条件下它们有所重叠。填埋气组分CO_2/CH_4摩尔比分别为0.5,0.7,0.9时,通过等高线法得到了生成适于费托反应的合成气组分所需的最适反应条件,而CO_2/CH_4摩尔比为1.1时,无法获得相应的最适反应条件。

Minimization of Gibbs free energy was applied to conduct thermodynamic analysis for syngas production from landfill gas partial oxidation reforming, where the landfill gas was simplified as a mixture of methane and carbon dioxide. The optimal reaction condition was obtained for production of syngas, which was suitable to be used in Fisher-Tropsch reaction. The results showed that the methane conversion is greater than 99% for the reaction temperature higher than 1 073 K, and both the increased temperature and O2/CH4 ratio could suppress the formation of solid carbon. The reaction conditions for maximum yields of CO and Hz were different, but they had some overlaps. The optimum reaction conditions for syngas production were obtained by contour plot at CO2/CH4 ratios of 0.5, 0.7, and 0.9, respectively. However, the optimum reaction condition could not be obtained for CO2/CH4 of 1.1.