Physical properties of activated sludge in a submerged membrane bioreactor and relation with membrane fouling

Application of flat-sheet membrane to thickening and digestion of waste activated sludge (WAS)

“…It is clear that apparent viscosity goes up with the increase of sludge concentration during each cycle. The results are well consistent with the study conducted by Khongnakorn et al [18]. The apparent viscosity increased from about 2 to about 30 mPa s as sludge concentration was enhanced from about the initial 5 g/L (except the cycles 5-7 with part of thickened sludge left in the reactor) to about 30 g/L.…”

Sludge filterability and dewaterability in a membrane bioreactor for municipal wastewater treatment

“…Studies on the physical and rheological properties of surplus sludge from MBRs have been carried out mainly at bench and small pilot scale. Sludge dewaterability was found to be very close to that of conventional activated sludge, regardless with the increasing suspended solids [14,15]. Concerning the apparent viscosity, there is a common consensus on the non-Newtonian thixotropic behaviour of the MBR sludge and most studies indicate an increasing trend with the MLSS concentration, generally better fit by the Ostwald model [15,16].…”

Effect of sludge retention time on sludge characteristics and membrane fouling of membrane bioreactor

“…EPS, consisting of polysaccharides, proteins, lipids and nucleic acids (Lee et al, 2003), were characterized in terms of soluble or bound polysaccharide and protein, since polysaccharides and proteins are considered as the most important constituents of EPS (Khongnakorn et al, 2005;Bai and Leow, 2002). Extraction of soluble and bound EPS in mixed liquor was carried out according to the methods of Lei and Zhou (2006), and Liu and Fang (2002).…”