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中国褐煤资源丰富,然而由于褐煤自身特点使其应用受到了极大的限制。针对中国褐煤应用最广的途径———燃烧,借助热重分析仪对不同热解终温的褐煤半焦及热解终温为1273 K的褐煤半焦与原煤的混合燃料的燃烧特性进行了分析。并利用Coats-Redfern法进行了燃烧动力学的分析,通过求得的表观活化能表征煤焦的燃烧反应活性。研究发现:热解终温越高,煤焦的燃烧特性越差;掺混褐煤有助于提高其半焦的燃烧特性,而掺混燃料的燃烧稳定性几乎和原煤无差别,且随着掺混比例的增加,混合燃料的活化能逐渐增大,越不易点燃,掺混半焦对燃料的燃烧特性和反应活性都有影响。相同制备条件下的烟煤半焦和褐煤半焦的燃烧动力学参数尤其是活化能相差很大,可见煤焦的燃烧反应活性与煤种有关。
China is rich in lignite resources, however, its application has been greatly restricted due to its own characteristics. In view of the most widely used means of burning lignite in China, the combustion characteristics of lignite with different pyrolysis final temperature and mixed fuel of lignite semi-coke with raw coal with a final temperature of 1273 K were studied by thermogravimetric analyzer analysis. The combustion kinetics was analyzed by Coats-Redfern method. The apparent activation energy was used to characterize the combustion activity of coal char. The results show that the higher the final pyrolysis temperature, the poorer the combustion characteristics of coal char. The blending of lignite helps to improve the combustion characteristics of the char, while the combustion stability of the blended fuel is almost the same as that of the raw coal. As the mixing ratio increases, the activation energy of the mixed fuel gradually increases, and the more difficult it is to ignite. The blended semi-coke affects both the combustion characteristics and the reactivity of the fuel. Under the same preparation conditions, the combustion kinetic parameters, especially the activation energy, of the bituminous coal semi-coke and lignite semi-coke are very different. It can be seen that the combustion reactivity of coal coke is related to coal type.