Carboxyls are inherent functional groups of thin-film composite polyamide nanofiltration (NF) membranes, which may play a role in membrane performance and fouling. Their surface presence is attributed to incomplete reaction of acyl chloride monomers during the membrane active layer synthesis by interfacial polymerization. In order to unravel the effect of carboxyl group density on organic fouli...

In an industrial seawater cooling system, the effects of three different antifouling treatments, viz. sodium hypochlorite (NaClO), aliphatic amines (Mexel®432) and UV radiation, on the characteristics of the fouling formed were evaluated. For this study a portable pilot plant, as a side-stream monitoring system and seawater cooling system, was employed. The pilot plant simulated a power plant s...

A single-fibre microfiltration system was employed to investigate the importance of various operating and sludge property parameters to the membrane fouling during sludge filtration. The sludge was obtained from a submerged membrane bioreactor (SMBR). A series of comparative and correlative filtration and fouling tests were conducted on the influence of the operating variables, sludge propertie...

The influence of the interaction between aquatic humic substances and the algal organic matter (AOM) derived from Microcystis aeruginosa on the fouling of a ceramic microfiltration (MF) membrane was studied. AOM alone resulted in a significantly greater flux decline compared with Suwannee River humic acid (HA), and fulvic acid (FA). The mixture of AOM with HA and FA exhibited a similar flux pat...

This study investigates the performance of ultrafiltration (UF) by membranes coated with titanium dioxide (TiO2) photocatalyst under ultraviolet (UV) illumination in removing natural organic matter (NOM) and possibly in reducing membrane fouling. Experiments were carried out using heat-resistant ceramic disc UF membranes and humic acids as model substances representing naturally occurring organ...

Organic conditioning films have been shown to alter properties of surfaces, such as hydrophobicity and surface free energy. Furthermore, initial bacterial adhesion has been shown to depend on the conditioning film surface properties as opposed to the properties of the virgin surface. For the particular case of nanofiltration membranes under permeate flux conditions, however, the conditioning fi...

Membrane bioreactors (MBRs) are advanced tools for biological wastewater treatment to obtain high-quality treated water using ultrafiltration or microfiltration membranes for solid–liquid separation2). Despite their advantages over the conventional activated sludge method, a major challenge associated with the use of MBRs is membrane fouling, which involves the clogging of membrane pores due to...

Membrane processes in drinking water applications are micro(MF), ultra(UF), and nanofiltration (NF). These processes remove turbidity and bacteria (MF), viruses and macromolecules (UF) and small molecules and hardness (NF). Of particular concern in water treatment is the removal of natural organic matter (NOM) which contains potential disinfection by-product precursors. The presence of colloids...

The mechanisms regarding the influence of dissolved organics in papermaking whitewater together with metal ions on the fouling of an ultrafiltration (UF) membrane were studied in this paper. A series of experiments were carried out to characterize the organic matters’ size and membrane flux. The associated fouling mechanism was investigated using the modified Hermia empirical model, resistance ...

Fouling behaviour and its impact on the rejection of trace organic contaminants (TrOCs) by forward osmosis (FO) were investigated.Membrane fouling was simulated using humic acid and colloidal particles asmodel foulants at different initial permeatewater fluxes.Water flux declinewas insignificant at an initial permeate flux of 9 L/m2h and the fouling layerwas loose and fluid-like. By contrast, t...