A series of reverse osmosis (RO) membrane filtration experiments was performed systematically in order to investigate the effects of various hydrodynamic and physicochemical operational parameters on a cake layer formation in colloidal and particulate suspensions. Bench-scale fouling experiments with a thin-film composite RO membrane were performed at various combinations of trans-membrane pres...

Magnetic separation is a very old separation technology, which is mainly used, in the mineral industry. In these applications, the magnetic force is applied to separate magnetic from non-magnetic materials. The separation efficiency strongly depends on the magnetic properties of the materials as well as the particle sizes. This paper introduces a totally new magnetic separation process, which c...

The technique that employs flash freezing and environmental scanning electron microscopy (ESEM) was utilised for detailed investigation of the fouling materials in a membrane bioreactor (MBR). The method involves the flash freezing of a wet sample in liquid nitrogen for 10s to preserve its structure for direct ESEM observation with a high image resolution. ESEM images show that the sludge cake ...

Downward and upward ultrafiltration (UF) was performed using the suspensions of nanosized colloidal silica with different particle diameters and their filtration rates were compared. In downward UF, the filtration rate decreases as the particle diameter decreases because the specific filtration resistance of the filter cake becomes significantly higher. In contrast, the filtration rate in upwar...

A mathematical model using classical cake-filtration theory and the surface-renewal concept is formulated for describing cross-flow microfiltration under dynamic and steady-state conditions. The model can predict the permeate flux and cake buildup in the filter. The three basic parameters of the model are the membrane resistance, specific cake resistance and rate of surface renewal. The model i...

SIMULATION OF DUST CAKE BUILD-UP ON THE FILTER MEDIUM This section describes a physical model for cake and pressure build-up on candle filters. The model was aimed at investigating filtration operation and reverse pulse cleaning of the filter. It is useful to calculate the filter cake thickness and pressure drop along the filter candle. Figure 1 shows the schematic diagram of filter cake build-...

Filtration of an isotonic suspension of baker's yeast through a 0.45-μm membrane was studied at two different pressures, 40 and 80 kPa, for yeast concentrations ranging from 0.14 to 51 kg/m(3) (dry weight). For a yeast volume fraction above 0.06 (~21.8 kg/m(3) ), the porosity of the yeast cake is less dependent on the suspension concentration. For highly diluted suspensions, the specific cake r...

In this work, the natural depletion process in sandstone and carbonate cores was modeled to investigate the asphaltene deposition mechanisms. A new permeability reduction correlation was proposed based on the Minssieux model that considers a combination of surface deposition, pore throat plugging, and filtration cake mechanisms. The results showed that the filtration cake is a dominant asphalte...

A laboratory scale external anaerobic dynamic membrane bioreactor (AnDMBR) treating high strength wastewater was operated to assess the effect of gas sparging velocity and organic loading rate on removal efficiency and dynamic membrane (DM) filtration characteristics. An increase in gas sparging velocity (GSV) results in a decrease in DM filtration resistance. DM or cake formation was identifie...