升温速率对沥青燃烧和气态产物释放特性的影响

采用热重-傅里叶变换红外光谱联用实验分析不同升温速率下沥青燃烧的失重过程，得到沥青燃烧过程中气态产物的析出规律，并利用Kissinger法计算沥青燃烧的动力学参数，为揭示火灾中沥青的燃烧机理和指导阻燃抑烟沥青设计提供重要的理论依据. 结果表明，沥青燃烧过程主要包括有氧热解和重质组分燃烧2个阶段，且两阶段的反应机理不同. 沥青有氧热解阶段包含3个失重峰，分别对应饱和分、芳香分和胶质的热解，3种成分燃烧的活化能依次增大；随着升温速率的增大，3个失重峰出现重叠，最大失重速率明显增加，气态产物的红外光谱吸收峰强度逐渐增强. 重质组分燃烧阶段的活化能相比胶质有氧热解更低，最大失重速率及红外光谱吸收峰强度随升温速率变化不大.

Effect of heating rate on asphalt combustion and gaseous products release characteristics

The mass loss process of asphalt combustion at different heating rates was analyzed by thermogravimetry coupled with Fourier transform infrared spectrometer. The release characteristics of gaseous products during asphalt combustion was obtained, and the kinetic parameters of asphalt combustion were calculated by Kissinger method, providing important theoretical basis to reveal the burning mechanism of asphalt and guide the design of flame-retardant and smoke-suppressive asphalt. Results show that asphalt combustion process mainly includes two stages: aerobic pyrolysis and heavy components combustion, and the reaction mechanisms of the two stages are different. There are three mass loss peaks in the aerobic pyrolysis stage, corresponding to the pyrolysis of saturates, aromatics, and resins, respectively, and the activation energies of the three components combustion increase accordingly. With the increase of heating rates, the three mass loss peaks overlapped, the maximum mass loss rate increased significantly, and the infrared spectrum absorption peak intensity increased gradually. While in the heavy components combustion stage, the activation energy is lower than that of resins aerobic pyrolysis, the maximum mass loss rate and the infrared spectrum absorption peak intensity does not change much with the heating rate.