温升速率对混合煤样热解的影响及动力学分析

为了节约动力煤,降低电力成本,为锅炉燃烧提供理论指导。采用热重分析法和热差分析法对褐煤和煤矸石的混合物进行热解实验。通过改变实验条件(温升速率)可以得到不同情况下的TG曲线、DSC曲线和转化率曲线。实验选用褐煤和煤矸石的质量比为2∶3,温升速率分别为10、30、50℃/min。10℃/min和50℃/min的煤样总的放热面积相近,但30℃/min的放热面积较小,说明30℃/min的温升速率不利于放热。由动力学分析得知,由于温升速率不同,活化能、频率因子均不同,热解动力学参数均发生一定变化。

Influence of heating rate on mixed coal sample pyrolysis and dynamic analysis

In order to save steam coal and reduce power cost,and to provide theoretical guidance for the boiler combustion,the pyrolysis test was carried out on lignite and coal gangue using thermogravimetric analysis and different thermal analysis.Get different situations of TG curves,DSC curves and conversion rates curve by changing the heating rate.The mass ratio of lignite to coal gangue is 2 ∶ 3,the heating rate is 10 ℃/min,30 ℃/min,50 ℃/min. The heat releasing areas of the coal sample are close when the heating rate is 10 ℃/min,50℃/min,while the heat releasing area is small when the heating rate is 30℃/min.The results show that,30℃/min is not suitable for heat releasing.The dynamic analysis show that,the activation energy,frequency factor,pyrolysis kinetics parameters change as the heating rate changes.