Optimizing MBR Performance: CFD and Experimental Insights on Aeration Design for Fouling Control
S. Khakpour, F. Nocera, S. Mauro, A. Latteri, C. Tosto and L. Saitta Department of Civil Engineering and Architecture (DICAR), University of Catania, via Santa Sofia 64, 95123 Catania (Italy).   2026-06-27

Abstract

The optimization of membrane bioreactor (MBR) systems is a critical challenge in mitigating membrane fouling. To overcome this issue, a two-phase experimental–computational approach was applied to evaluate the effect of the distance between the aeration pipe and the membrane module on antifouling performance. In the first phase, flat-sheet membranes were fabricated by the NIPS (Non-solvent Induced Phase Separation) method and characterized by field emission scanning electron microscopy (FESEM), pure water flux (PWF), and contact angle measurements. Among the prepared membranes, M2 membrane exhibited the highest PWF of 134 L·m⁻ ²·h⁻ ¹, the lowest contact angle of 80.0°, and a more favourable pore size distribution. In the second phase, a computational fluid dynamics (CFD) model was developed to simulate the hydrodynamic conditions around the selected membranes (M2). Increasing the distance improved the uniformity of shear stress distribution across the membrane surfaces. D2 = 60 mm was identified as optimal, as it allowed the system to utilize its full filtration potential while experiencing lower surface friction, thereby reducing fouling. D2 = 60 mm results in the lowest average shear stress (~0.30 Pa), provides the most balanced stress regime, minimizing localized abrasion while maintaining sufficient shear for antifouling, and thereby supporting longer membrane lifespan.

Key words: Membrane, CFD, MBR, Fouling.

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