委内瑞拉减压渣油的热解特性及其动力学研究

采用热重-质谱(TG-MS)联用对委内瑞拉减压渣油在不同升温速率下进行热解实验，研究其热解反应特性，并采用3种等转化率法和分布活化能模型(DEAM)求取减压渣油热解反应的动力学参数。实验结果表明，委内瑞拉减压渣油的热解主要反应温度区间为179～490℃,总质量损失率为77.54%,质量损失峰值在446℃达到最大，最大质量损失速率为317.38μg/min。Flynn-Wall-Ozawa(FWO)法比其他2种等转化率法能更好地描述减压渣油的热解过程，由其计算得到的热解活化能为56.77～178.91 kJ/mol。进一步采用DEAM模型将减压渣油分为4个假定组分，对升温速率为10℃/min条件下的热重分析(TG-DTG)数据进行分峰拟合，求得饱和分、芳香分、胶质和沥青质四组分动力学参数，并据此获得减压渣油总活化能分布曲线。结果表明，委内瑞拉减压渣油活化能主要集中在100～250 kJ/mol范围内，通过加权求和获得平均活化能为190.11 kJ/mol。

Study on the Pyrolysis Characteristics and Kinetics of Venezuela Vacuum Residue

Thermogravimetric mass spectrometry (TG-MS) was adopted for the pyrolysis experiment on Venezuela vacuum residue at different heating rates to study the pyrolysis reaction characteristics, and three iso-conversional methods and the distribution activation energy model (DAEM) were used to obtain the kinetic parameters of pyrolysis action for vacuum residue. The results show that the main temperature range for the pyrolysis reaction of Venezuela vacuum residue is 179—490 ℃, the total mass loss rate is up to 77.54%, the mass loss hits the peak at 446 ℃, and the maximum mass loss rate is 317.38 μg/min. It js found that compared with other two iso-conversional methods, Flynn-Wall-Ozawa (FWO) method can better describe the pyrolysis process of vacuum residue， and the pyrolysis activation energy calculated by FWO method is 56.77—178.91 kJ/mol. Later, vacuum residue was further divided into four hypothetical components by DAEM, and TG-DTG data at the heating rate of 10 ℃/min were fitted by peaks to obtain the kinetic parameters of four components (i.e., saturates, aromatics, resins and asphaltenes), as well as the total activation energy distribution curve of vacuum residue accordingly. The results indicate that the activation energy of Venezuela vacuum residue is mainly concentrated in the range of 100—250 kJ/mol, and the average activation energy obtained by weighted summation is 190.11 kJ/mol.