Micro-CFD modelling of ultrafiltration bio-fouling
Francesco Petrosino, Giorgio De Luca, Stefano Curcio, S. Ranil Wickramasinghe, Sudip Chakraborty
Abstract
Concentration polarisation on the membrane process is a vast area of interest. The macroscopic characterisation of fouling structure formation occurring during the Ultra-Filtration (UF) of Bovine Serum Albumin (BSA) was studied in this work. A twisted Monte-Carlo (MC)/Computational-Fluid-Dynamic (CFD) approach was developed to calculate macroscopic fluid-dynamic proprieties. Different fluid-dynamic simulations were performed based on the knowledge acquired by an MC analysis that provided boxes of adsorbed molecules (i.e., 3D proteins meso configurations on the UF membranes surface). These represented the deposit layers formed at different distances from the membrane. The 3D meso structure were imported into a bespoke simulation environment, and several meshes were created to perform micro-fluid dynamic calculations (m-FD). From these simulations, a set of macroscopic parameters was calculated. The resistance to the flow of deposit layers accumulated on the membrane surface, Radd, usually estimated by experimental methods, was computed starting from the ab-initio knowledge acquired at sub-nanoscopic scale. Therefore, this work provides a multi-scale description of a complex phenomenon such as that of protein fouling during a UF filtration starting from a sub-nanometric scale.