A novel Euler-Lagrange approach to simulate gas-liquid mass transfer coefficient () in bubbly flow regimes, Chemical Engineering Science, under review (2025).
Descripción del recurso
Ozonation is widely studied for water/wastewater disinfection and decontamination. Membrane technologies, namely tube-in-tube configuration, enhance gas–liquid contact area. However, determining the mass transfer coefficient (kL) is challenging, as most available models are empirical and limited to specific systems. Analytical models, like Higbie’s and Danckwerts’, predict kL without system dependency but are constrained to bubbles larger than 10−3 m. Membrane contactors generate much smaller bubbles, requiring a different approach. This study proposes a novel kL expression derived from the transient species transport equation in spherical coordinates. The model was integrated into a 3D CFD Euler-Lagrange simulation coupled with experimental bubble size data to evaluate ozonation in a tube-in-tube reactor with an upward helicoidal flow. The novel method calculated the and for ozone ( up to 1.32 × 10-4 m s−1, and up to 1.15 × 10-1 s−1) and oxygen ( up to 2.42 × 10-4 m s−1, and up to 2.10 × 10-1 s−1), achieving results that agreed well with the experimental data with a maximum deviation not exceeding 7 %. Compared to empirical models, the novel approach accurately predicted kL values for smaller bubbles in membrane systems.