The Soret and Dufour Effects in Non-thermal Equilibrium Packed Beds with Forced Convection and Endothermic Reactions

• Published in: Chinese journal of chemical engineering Vol. 21; no. 8; pp. 867 - 875
• Main Author: 李明春 赵中亮 静宇 刘家涛 吴玉胜
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.08.2013
• Subjects: Chemical engineering; Conversion; cross-diffusion effects; Endothermic reactions; Feeding; Forced convection; heat and mass transfer, thermal decomposition; Mass transfer; Mathematical models; Peclet number; Peclet数; porous packed bed; 初始温度; 吸热反应; 强制对流; 最大相对误差; 气体产物; 盒装; 非热平衡; heat and mass transfer, thermal decomposition; porous packed bed; cross-diffusion effects
• ISSN: 1004-9541; 2210-321X
• DOI: 10.1016/S1004-9541(13)60502-X

To study the influence of the Soret and Dufour effects on the reactive characteristics of a porous packed bed with endothermic reactions and forced convection, a two-dimensional mathematical model considering the cross-diffusion effects was developed in accordance with the thermodynamics of irreversible processes and the local thermal non-equilibrium model. The simulation results were validated by comparing with experimental data. The influence of the Soret and Dufour effects on the heat transfer, mass transfer and endothermic chemical reaction in the non-thermal equilibrium packed bed is discussed. It was found that when the Peclet number reaches 1865, the maximum relative error of the concentration of gas product induced by the Soret effect is 34.7% and that of the solid fractional conversion caused by the Dufour effect is 10.8% at reaction time 160 s and initial temperature 1473 K. The differences induced by the Soret and Dufour effects are demonstrated numerically to increase gradually with the initial temperature of feeding gas and the Peclet number.