升温速率对卷烟烟丝快速热解的影响

Effects of heating rate on fast pyrolysis of cut filler of cigarette

为考察升温速率对卷烟烟丝快速热解行为的影响,采用热重-质谱联用技术对卷烟烟丝在不同升温速率(200 K·min^(-1)~800 K·min^(-1))下的热解特性进行研究,并建立了不同升温速率下卷烟烟丝的快速热解动力学模型。结果表明:(1)随着升温速率的升高,烟丝各主要成分热分解温度区间的叠加程度、热解速率以及释放特性指数均呈递增趋势,且有不同程度的热滞后现象。(2)引入升温速率校正因子的动力学模型能够克服热滞后所引起的动力学参数偏差,可以更好地预测不同升温速率下卷烟烟丝的快速热解行为。(3)高升温速率下,热解烟气产物中质荷比(m/z)为56(丙烯醛)、79(吡啶)、84(烟碱)、94(苯酚)和117(吲哚)的化合物释放量减小。在高升温速率下卷烟烟丝的快速热解特性与卷烟燃烧的真实状态更为接近,建立的卷烟燃烧数学模型更加准确。

In order to study the effects of heating rate on fast pyrolysis of cut filler of cigarette, TGA（Thermogravimetric Analyzer） combined with QMS（Quadrupole Mass Spectrometers） was applied to investigate the pyrolysis characteristics of cut filler of cigarette at different heating rates（200 K·min^（-1）-800 K·min^（-1））, and a kinetic model for the fast pyrolysis of cut filler at different heating rates was developed. The results showed that： 1） With the increase of heating rates, thermal decomposition overlap region, mass loss rate and devolatilization index of each main component in tobacco were raised. Meanwhile, thermal lags of different extents were also observed. 2） The kinetic model overcame the deviation of kinetic parameters caused by thermal lag via introducing a heating rate correction factor, and predicted the fast pyrolysis behaviors of cut filler at different heating rates more accurately. 3） The release of pyrolysis products, such as acrolein（m/z=56）,pyridine（m/z=79）, nicotine（m/z=84）, phenol（m/z=94） and indole（m/z=117） decreased with the increase of heating rate. The fast pyrolysis characteristics of cut filler are closer to the real state of cigarette combustion and the developed mathematical model for tobacco pyrolysis kinetics is more accurate at high heating rate.