LAUSR

Concentration profiles and structural organization of different colloidal suspensions in the vicinity of membrane during ultrasonic-assisted ultrafiltration were previously evidenced from non-destructive, real-time, in-situ SAXS measurements (Jin et al., 2014 [11], Jin et al., 2014 [12]). On the basis of these obtained results, this paper explored by numerical calculation, four key factors of the buildup of concentrated polarization layer in such process (matter accumulation, flow property, permeability and osmotic pressure). Two different kind of systems have been studied: anisotropic Laponite clay particles and soft casein micelle particles. For all the systems and filtration conditions investigated, the results have shown that the level of matter accumulated is directly linked to calculated permeation flux and in accordance with the experimental one. The rheological parameters introduced in the calculations have allowed to deduce the charts of yield stress in the concentrated layers and revealed the important role of suspensions flow properties in the mechanisms of filtration involved near the membrane surface. The measured properties of the accumulated layers have been computed with a recent model based upon permeability and osmotic pressure (Bouchoux et al., 2013 [17]). It has been shown good agreement between modeled and experimental values in permeation flux for all the different systems and filtration explored.