The purpose of this work was to examine the settling properties of activated sludge from a sequencing batch reactor (SBR). The experiments were carried out in a bench-scale reactor, fed with wastewater from the University of Olsztyn treatment plant. Concentrations of the examined activated sludge varied between 2.5 and 6.0 kg SS m. Laboratory analyses of the sludge comprised: sludge concentrati...

The organic composition of the feed sludge to six laboratory-scale anaerobic digesters was adjusted by substituting a proportion of the primary sludge for glucose or propionic acid solution. Substitution with glucose caused an increase in the microbial extracellular polymer (ECP) content of the digested sludge, which altered the particle size distribution of the sludge and made the sludge more ...

An understanding of sludge rheology during anaerobic digestion can improve digester performance, particularly with regards to mixing. However, the “black box” nature of digesters limits the knowledge on sludge flow behaviour, once it enters the digester. A study on the flow properties (i.e. apparent viscosity and yield stress) as well as the yielding and restructuring behaviour of primary, seco...

Organic compounds present in the bleached kraft pulp mill (BKPM) effluents may be reduced by biological treatment like: activated sludge (AS) or aerated lagoon (AL). However, after biological treatment, BKPM effluent still contains specific compounds. Some of them have been related with chronic effects (DNA damage, reproductive and physiological) observed on fishes exposed to BKPM effluents. Th...

During the past several years, waste produced by the electroplating industry has attracted attention due to the level of pollutants found in the waste stream, the difficulty associated with treatment, and the cost of waste disposal. EPA has enacted regulations to control the discharge from plating facilities and estimates that 140 million lb of metal pollutants will be prevented from being disc...

Utilization of sewage sludge on land is an appealing sludge disposal method. The reasons are not just because of the environmental and economic constraints associated with other disposal methods such as incineration and landfilling, but also because the sludge is beneficial both as a soil conditioner and as a fertilizer [1,2]. However, the major limitation with land application of sewage sludge...

Sludge management in waste stabilization ponds (WSPs) is essential for safeguarding the system performance. Sludge accumulation patterns in WSPs are strongly influenced by the pond hydrodynamics. CFD modeling was applied to study the relation between velocity profiles and sludge deposition during 10 years of operation of the Ucubamba WSP in Cuenca (Ecuador). One tracer experiment was performed ...

Aerobic granular sludge was cultivated adopting internal-circulate sequencing batch airlift reactor. The contradistinctive experiment about short-term membrane fouling between aerobic granular sludge system and activated sludge system were investigated. The membrane foulants was also characterized by Fourier transform infrared (FTIR) spectroscopy technique. The results showed that the aerobic g...

Dewatering of sewage sludge is an important part of proper sludge management practice. It is becoming a more challenging issue for water industries as new regulations on sludge disposal are being imposed. In this paper, the application of mechanical thermal expression (MTE) to dewater sewage sludge and the conditioning of sludge by mixing with brown coal are investigated. Raw sludge, sludge flo...