Work

Gas–liquid mass-transfer modeling in industrial-scale bioreactors: A standardized framework and critical assessment

Year: 2025

Type: article

Abstract: Gas transfer often limits large-scale bioprocesses, demanding robust models for design, scale-up, and scale-down. This study establishes a standardized computational framework for gas–liquid mass-transfer modeling in industrial-scale bioreactors, integrating and evaluating the main sub-models governing k L a prediction — bubble dynamics, interfacial area, drag laws, and turbulence closures — within CFD simulations of a 134 m 3 bubble column and a 96 m 3 Rushton-impeller stirred tank. A systematic sensitivity analysis reveals that bubble size modeling (including pressure and coalescence corrections) and drag law selection are the dominant parameters controlling gas holdup and interfacial area, while k L correlations and bubble-induced turbulence models exert secondary but non-negligible influence on local extremes of k L a . Among tested formulations, the Grace–Simonnet drag law, hybrid (Higbie–Lamont–Scott) k L approach, and variable single-bubble-size model offered the best trade-off between physical realism and computational cost. The results are consolidated into a decision chart that ranks sub-model relevance and guides model selection based on reactor type and turbulence regime. This framework provides decision-ready guidance for reliable, scale-consistent CFD modeling of gas–liquid mass transfer in large-scale bioreactors.

Source: Chemical Engineering Journal Advances

DOI: 10.1016/j.ceja.2025.100982