Critical flux and particle deposition of fractal flocs during crossflow microfiltration

The critical flux and particle deposition of fractal flocs during crossflow microfiltration were investigated experimentally in this study. Flocculated hematite flocs were used as the model flocs. The critical flux was determined based on the observation of floc deposition using the Direct Observation Through Membrane (DOTM) technique. The experimental results showed that in addition to the particle size distribution, the fractal structure of the flocculated flocs also exerted a strong influence on the fouling mechanisms. Larger flocs typically yielded higher critical fluxes as in monodisperse suspensions, and the effect of particle size was less pronounced for the more porous flocs. The critical flux was also found to increase with the fractal dimension, especially for the larger flocs.