Enhanced biological phosphorus removal

Enhanced biological phosphorus removal (EBPR) is a sewage treatment configuration applied to activated sludge systems for the removal of phosphate. The common element in EBPR implementations is the presence of an anaerobic tank (nitrate and oxygen are absent) prior to the aeration tank. Under these conditions a group of heterotrophic bacteria, called polyphosphate-accumulating organisms (PAO) are selectively enriched in the bacterial community within the activated sludge. In the subsequent aerobic phase, these bacteria can accumulate large quantities of polyphosphate within their cells and the removal of phosphorus is said to be enhanced. Generally speaking, all bacteria contain a fraction (1-2%) of phosphorus in their biomass due to its presence in cellular components, such as membrane phospholipids and DNA. Therefore, as bacteria in a wastewater treatment plant consume nutrients in the wastewater, they grow and phosphorus is incorporated into the bacterial biomass. When PAOs grow

About this result

This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.

Related publications (16)

Related publications

Related people (4)

, , ,

Related people

Related units (1)

Related units

Related concepts (2)

The activated sludge process is a type of biological wastewater treatment process for treating sewage or industrial wastewaters using aeration and a biological floc composed of bacteria and protozoa.

Sewage treatment (or domestic wastewater treatment, municipal wastewater treatment) is a type of wastewater treatment which aims to remove contaminants from sewage to produce an effluent that is

Related concepts

Related courses (2)

Related courses

Related lectures (6)

Related lectures

Optimizing the extraction of extracellular DNA of aerobic granular biofilms

Katarzyna Bialek

Formation and properties of aerobic granules for enhanced biological phosphorus removal (EBPR) from sequencing batch reactor (SBR) strongly depend on the extracellular polymeric substances (EPS) in which the microorganisms are embedded. The composition of EPS varies between different species but mostly it is made up of proteins, polysaccharides and extracellular DNA (eDNA), that has been recently recognized as an important structural component. Although great amount of literature on the EPS extraction is available, till now, there is no standardized protocol for EPS extraction. Extraction methods involving multi step processes seem to be the most promising, although too harsh extraction procedures can lyse the cells and release intracellular compounds, which contaminate the EPS samples creating bias. Commonly employed intracellular markers of cell lysis i.e. Glucose-6-phosphate dehydrogenase (G6PDH) or 2-keto-3deoxyoctonate (KDO) are not always applicable, especially in systems where glycolysis does not occur and in mixed communities with gram-positive bacteria, respectively. Therefore a new method to measure cell lysis is needed. The activity of isocitrate dehydrogenase (ICDH), an ubiquitous enzyme found in all living organisms utilzing the Krebs (citric acid) cycle, has been assessed. Initial assays using this enzyme activity during EPS extraction revealed to be very sensitive to detect cell lysis in samples from mixed microbial communities as granular sludge biofilms cultivated in SBR. Preliminary results of EPS extraction using multi-step method and enzymatic extraction as well as selection of appropriate dyes to visualize and distinguish intracellular and extracellular DNA in granular samples from the reactor are discussed.

2016

Identification of microorganisms in Aerobic Granular Sludgeactively involved in biological phosphorus removal

Arnaud Michel Gelb

One of the aims of the treatment of domestic and industrial wastewater is the removal of phosphorus prior to discharge into the environment. Since phosphorus concentrations in wastewater exceed the requirement of bacterial growth, biological phosphorus removal is based on the ability of a group of microorganisms, named “Polyphosphate Accumulating Organisms” (PAO), to form large quantities of polyphosphate in their cells. In this study, we are focussing on the bacteria actively involved in the phosphorus removal in a lab scale bioreactor operated with aerobic granular sludge technology. This process based on dense microbial biofilms is a cost-effective and land-saving alternative to the conventional wastewater treatment with activated sludge. The identification of the microorganisms belonging to PAO relies on their distinct phenotype assessed with fluorescent probes targeting the intracellular polyphosphate structures. Sequencing of the 16S rRNA gene amplicons of PAO selected with flow-cytometry will be used to reveal the phylogenetic affiliation of the different actors involved in the phosphorus removal. This is of particular significance since low abundant microorganisms may play an important role in the phosphorus removal performance of aerobic granular sludge. We hypothesize that the maintenance of different populations involved in the same functional process is explained by multiple ecological niches present in such biofilm structures.

2016

Identification of microorganisms in Aerobic Granular Sludgeactively involved in biological phosphorus removal

Arnaud Michel Gelb

2016

The activated sludge process is a type of biological wastewater treatment process for treating sewage or industrial wastewaters using aeration and a biological floc composed of bacteria and protozoa.

Sewage treatment (or domestic wastewater treatment, municipal wastewater treatment) is a type of wastewater treatment which aims to remove contaminants from sewage to produce an effluent that is

ENV-167: Introduction to environmental engineering

This introduction to Enviromental Engineering is meant to show the students how upcoming courses in mathematics, physics, chemistry, biology and other areas will be used to gain a scientific understanding of environmental problems and then help to solve them.

ENV-405: Water and wastewater treatment

This course on water and wastewater treatment shows how to implement and design different methods and techniques to eliminate organic matter, nitrogen and phosporous from wastewater, and how to apply physical and chemical methods and techniques to produce drinking water.