Chemical Engineering Journal, Vol.172, No.1, 476-486, 2011
Detoxification of high-strength liquid pollutants in an ozone bubble column reactor: Gas-liquid flow patterns, interphase mass transfer and chemical depuration
The contemporary status of computational flow modelling is encouraging the application of modern CFD codes to the design and investigation of multiphase reactors. Aiming to accomplish novel and stringent environmental regulations on the decontamination of high-strength wastewaters, here we present a comprehensive discrete bubble model for the ozonation of liquid pollutants. As long as a bubble column reactor can operate on a multitude of hydrodynamic regimes, first we developed an Euler-Lagrange CFD model coupling the transport processes such as momentum and mass transfer, and ozonation kinetics. The model has been reasonably accounted for the dependency of flow regimes and extent of interaction among gas and liquid phases. Second, a quantitative assessment between computed and experimental gas and liquid superficial velocities indicated that ozone velocity and concentration play a prominent role on the mineralization rate. We found that the process efficiency has been increased until it reveals a quasi-steady behavior which indicated that the reaction system happens to be noticeably reliant on oxidant concentrations under bubbly flow conditions. Finally, interstitial flow maps were effectively corroborated with total organic carbon concentration profiles as function of inlet bubble velocities and ozone concentrations. (C) 2011 Elsevier B.V. All rights reserved.