FOULING MECHANISMS AND COMPARATIVE PERFORMANCE OF 4 ALUMINA MEMBRANES - CASE OF GELATIN ULTRAFILTRATION

This paper deals with gelatin ultrafiltration using alumina membranes of various pore sizes (0.2, 0.8, 1.4 et 2.0-mu-m). Pressure, tangential velocity and concentration effects are successively examined. From both a quantitative analysis of experimental data (pure solvent fluxes with clean or prefouled membranes, ultrafiltration fluxes, percent protein rejection) and the application of traditional model equations (filtration theory, film model), fundamental hypotheses are suggested concerning membrane functional characteristics. In particular, it is how fouling mechanisms and protein deposit structures are related to membrane characteristics. Finally, a comparison of membrane performances leads to the conclusion that the best fluxes and percent protein rejections are obtained using the 0.2-mu-m pore size membrane.