Four kinds of Wulagai lignite semi-coke samples were prepared by pyrolysis using different pyrolytic parameters. The BET area and pore structure of the samples was characterized through gas adsorption method, the CO2 gasification activity of the samples was examined by TGA method, and the samples were gasified in a tube furnace and the CO volume concentration variation with temperature was measured. The results show that, faster temperature rising rate and shorter pyrolysis time could help increasing the BET are and hole volume of the Wulagai semi-coke samples. The sample with final pyrolysis temperature of 700℃ had larger BET area than that with final pyrolysis temperature of 520℃, but its gasification reactivity was lower relatively. The temperature was about 850℃ when the four samples' gasification rate reached the maximum. Considering the pore structure, gasification activity, fuel property and gasifiers characteristics of the Wulagai lignite semi-coke, it is recommended that the pyrolysis of Wulagai lignite should be carried out at low temperature, with rapid heating rate and rapid pyrolysis process, and the gasification should be controlled by entrained-flow gasification technologies. This results can provide reference for optimizing the pyrolysis process and gasification utilization of Wulagai lignite semi-coke.%采用不同热解参数制备了4种乌拉盖褐煤半焦样品,并利用气体吸附法对其进行了比表面积及孔径结构的测定,利用热重分析法进行半焦样品的CO2气化反应活性的测定,利用管式炉对半焦样品进行气化并测量了CO体积分数随温度的变化情况.试验结果表明:较快的升温速率、较短的热解时间有助于提高乌拉盖褐煤半焦的孔隙率及孔容积;热解终温为700℃的乌拉盖褐煤半焦比表面积大于热解终温为520℃,但其气化反应活性却相对较低;各半焦样品气化反应速率最高时对应的温度为850℃左右;根据乌拉盖褐煤半焦的孔径结构、气化反应活性、煤质特性以及各气化炉的工艺特点,推荐乌拉盖褐煤热解过程采取低温、快速升温、快速热解的工艺,其气化过程采用气流床气化技术.本研究结果可为乌拉盖褐煤热解工艺优化以及乌拉盖半焦的气化利用提供参考.
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