针对电厂掺烧褐煤缺乏相关理论指导的技术需求，采用热重分析方法系统考察了包煤、准煤和褐煤的单独燃烧特性，并将两种烟煤分别以10％、30％、50％和70％的比例在相同条件下与褐煤混合燃烧，根据各燃料燃烧特征参数计算了单一煤种及其不同掺混比例的着火指数、燃尽指数和综合燃烧指数。结果表明，褐煤最易着火和燃尽；包煤着火特性较好，但在550～660℃范围内出现难燃峰致使燃尽特性变差；准煤的着火特性最差，燃尽特性略优于包煤；将包煤和准煤与褐煤掺混后燃烧特性有所改善，各燃烧特征温度降低，且综合燃烧指数随褐煤掺烧比例的增加而增加。建议在电厂实际应用时，褐煤的掺烧比例控制在30％－50％之间。%Based on the actual requirement for fundamental theory of blending lignite in coal-fired power stations, combustion characteristics of lignite, bituminous coal and their blends were investigated by using thermogravimetric method ( TGA) in this paper.Lignite was blended with two types of bituminous coals in proportions of 10%, 30%, 50%and 70%, respectively.The ignition index, burnout index and comprehensive combustion index of single and mixed fuels were calculated by means of combustion characteristic parameters.The results show that lig-nite displays the best ignition and burnout performace, Bao coal is easier to ignite but hard to burn out in the tem-perature range of 550 and 660℃.Compared to Bao coal, Zhun coal is the hardest to ignite but better to burn out. The performance of combustion can be improved after blending lignite, which is largely because the comprehensive combustion index of blended coals increases with the increasing ratio of lignite.Therefore, the blending ratio of lig-nite suggested lignite ration should be controlled between 30%and 50%.
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