Calcium and ash accumulation in aerobic granules treating organic wastewater was investigated systematically in this study. It was found that ash content of granular sludge reached 43% at stable state of reactor operation with calcium carbonate precipitation as the main cause. Since granular sludge in the reactor at the steady state was the mixture of granules with different sizes, granules in ...

The effect of salinity on aerobic granular sludge treating fish-canning wastewater was evaluated through a biofilm model. addition inhibition term to the model could accurately describe reactor performance with different salinities.

Full-scale wastewater treatment plants utilizing aerobic granular sludge technology are being built in many countries worldwide. As with all biological plants, the produced waste biomass must be stabilized to protect population, wildlife, and environment. Digestion is usually used break down complex organics sludge; however, digestibility of still needs fully understood compared conventional ac...

In this study, the performance of two aerobic sequencing batch reactors (SBR) in removing carbon and nutrient (N & P) from Faraman’s industrial estate wastewater (FIW) with flocculated and granulated sludge were compared. The comparison study was performed by varying two significant independent variables (aeration time and mixed liquor volatile suspended solids (MLVSS)). The experiments were co...

Reaction constants and heat release during thermophilic aerobic digestion of typical secondary and mixed sludges were determined. Maximum reaction constant, determined by measuring the amounts of biodegradable volatile suspended solids (bVSS) removed, occurred in the temperature range of 55-60 ºC. Measurement of heat releases were carried out, at the same range, by the aid of a temperature ...

Activated sludge was successfully incorporated as the biocatalyst in the fast, ferricyanide-mediated biochemical oxygen demand (FM-BOD) bioassay. Sludge preparation procedures were optimized for three potential biocatalysts; aeration basin mixed liquor, aerobic digester sludge and return activated sludge. Following a 24h starving period, the return activated sludge and mixed liquor sludges repo...

A comprehensive study of the ecophysiology of the filamentous Meganema perideroedes affiliated to the Alphaproteobacteria, possessing a "Nostocoida limicola Type II" filamentous morphology was conducted. This morphotype often causes serious bulking problems in activated sludge wastewater treatment plants, and hardly anything is known about its physiology. The study was carried out by applying a...

The effects of silver (Ag) nanoparticles (NPs) on activated sludge in a biological nitrogen removal (BNR) process were investigated under aerobic and anoxic conditions. We show that nitrification was more vulnerable to Ag NPs exposure than denitrification at the same Ag NPs concentration. In continuous operation of the BNR process, a higher inhibitory effect on nitrification was attributed to a...