Microbiome structure and function in parallel full-scale aerobic granular sludge and activated sludge processes

Aerobic granular sludge (AGS) and conventional activated sludge (CAS) are two different biological wastewater treatment processes. AGS consists of self-immobilised microorganisms that are transformed into spherical biofilms, whereas CAS has floccular sludge of lower density. In this study, we investigated the treatment performance and microbiome...

Coupling high-rate activated sludge process with aerobic granular sludge process for sustainable municipal wastewater treatment

Achieving a neutral/positive energy balance without compromising discharge standards is one of the main goals of wastewater treatment plants (WWTPs) in terms of sustainability. Aerobic granular sludge (AGS) technology promises high treatment performance with low energy and footprint requirement. In this study, high-rate activated sludge (HRAS...

Impact of primary sedimentation on granulation and treatment performance of municipal wastewater by aerobic granular sludge process

Aerobic granules contain microorganisms that are responsible for carbon, nitrogen, and phosphorus removal in aerobic granular sludge (AGS) process in which aerobic/anoxic/anaerobic layers (from surface to core) occur in a single granule. Optimizing the aerobic granular sludge (AGS) process for granulation and efficient nutrient removal can be...

Exploring the Limits of Polyhydroxyalkanoate Production by Municipal Activated Sludge

Municipal activated sludge can be used for polyhydroxyalkanoate (PHA) production, when supplied with volatile fatty acids. In this work, standardized PHA accumulation assays were performed with different activated sludge to determine (1) the maximum biomass PHA content, (2) the degree of enrichment (or volume-to-volume ratio of PHA...

Toward achieving sustainable management of municipal wastewater sludge in Egypt: The current status and future prospective

Over the past 4 decades, the increasing amounts of excess sludge from municipal wastewater treatment plants (WWTPs) represent a challenge toward achieving the sustainability of the drinking water and sanitation sector in Egypt, resulting in a serious environmental pollution due to the uncontrolled use of non-stabilized sludge. Here, we report a...

Digestibility of waste aerobic granular sludge from a full-scale municipal wastewater treatment system

Full-scale aerobic granular sludge technology under the trade name Nereda® has been implemented for municipal, as well as industrial wastewater treatment. Owing to the operational reactor procedures, two types of waste aerobic granular sludge can be clearly distinguished: 1) aerobic granular sludge selection discharge (AGS-SD) and 2) aerobic...

Structural extracellular polymeric substances determine the difference in digestibility between waste activated sludge and aerobic granules

Aerobic granular sludge (AGS) technology is an alternative to conventional activated sludge to reduce the process footprint and energy consumption. Strategies for the efficient management of its produced biomass, that is grown in a granular morphology as well, need further development. Anaerobic digestion (AD) is commonly applied in waste...

Comparative evaluation of the sludge characteristics along the height of upflow anaerobic sludge blanket coupled ultrafiltration systems

This study provides a comparison of the sludge characteristics along the height of an upflow anaerobic sludge blanket (UASB) reactor in terms of sludge morphology, activity and stability. The main aim of this study was to identify the best location (i.e. where sludge is of lowest stability and/or highest concentration) in the sludge bed for...

Mainstream partial nitritation and anammox: Long-term process stability and effluent quality at low temperatures

The implementation of autotrophic anaerobic ammonium oxidation processes for the removal of nitrogen from municipal wastewater (known as "mainstream anammox") bears the potential to bring wastewater treatment plants close to energy autarky. The aim of the present work was to assess the long-term stability of partial nitritation/anammox (PN/A)...