Numerical simulation of reactive pulsing flow for the catalytic wet oxidation in TBR using a VOF technique

Abstract

Guided by the intrinsic advantages of the dynamic nature of mass/heat transfer fluctuations in pulsing flow, here we performed volume-of-fluid (VOF) numerical simulations to evaluate how liquid flow modulations can improve the detoxification of liquid effluents by catalytic wet oxidation. First, prominent numerical parameters were optimized in terms of mesh aperture and time step. Second, the effect of oxidation temperature and the influence of gas and liquid flow rates have been investigated comparatively under different flow regimes. The VOF computations have correctly handled the experimental observations both in terms of the axial conversion and temperature. The increase of oxidation temperature was found to move the trickling and pulsing intersection point on the conversion toward the top of the trickle bed. Finally, in comparison with trickling flow regimes, these computed and experimental findings revealed a considerable improvement on the detoxification of organic matter highlighting the benefits of process intensification covered by the periodic liquid flow modulations. © 2011 American Institute of Chemical Engineers AIChE J, 2012