利用热重分析技术研究了不同载气流量、载气气氛和升温速率下柴油的热解过程.比较分析了单一反应模型和DAEM模型对柴油热解动力学分析的适应性.结果表明,单一反应模型不能在整个温度区间内对柴油热解特性进行预测;而DAEM模型可以由3条不同升温速率下的失重曲线直接得到不同失重率下柴油热解的活化能分布和频率因子的值,较为准确地求解动力学参数.由DAEM模型所得的不同气氛下活化能分布曲线表明,CO2气氛中柴油稳定性更好;柴油在CO2气氛中比N2气氛中热解速度大.
The pyrolysis process of diesel was investigated via thermo-gravimetric analysis at different heating rates,atmosphere and gas rates. Compared with the single reaction energy model,the distribution activation energy model(DAEM)is more applicable to the analysis of diesel pyrolysis. The results indicate that the single reaction energy model can not predict the pyrolysis characteristics of diesel within the whole experimental temperature range. While activation energy and pre-exponential factors can be obtained by the DAEM model on the basis of 3 thermogravimetric curves at different heating rates,which are more accurate and acceptable. The curve of activation energy from DAEM model under different atmosphere shows that the diesel is more stable in CO2 atmosphere than that in N2 atmosphere,and that the pyrolysis rate of diesel in CO2 atmosphere is higher than that in N2 atmosphere.