Effect of the anaerobic solids retention time on enhanced biological phosphorus removal

1994 ◽  
Vol 30 (6) ◽  
pp. 193-202 ◽  
Author(s):  
Yoshitaka Matsuo
Keyword(s):  
Retention Time ◽  
Phosphorus Removal ◽  
Continuous Flow ◽  
Phosphate Removal ◽  
Substrate Uptake ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
Solids Retention ◽  
Biological Phosphorus ◽  
P Removal

Three continuous flow enhanced biological phosphorus removal (EBPR) systems were operated to investigate the effect of the anaerobic SRT on the phosphate removal. The P removal in the system with a short anaerobic SRT declined due to growth of non phosphate accumulating microbes which competed in anaerobic substrate uptake against polyphosphate accumulating bacteria. The phosphorus removal, however, was improved by extending the anaerobic SRT. Restoration and stabilization of P removal by the long anaerobic SRT were confirmed in two other systems.

scholarly journals Pushing the limits of solids retention time for enhanced biological phosphorus removal: process characteristics and Accumulibacter population structure

2020 ◽  
Vol 82 (8) ◽  
pp. 1614-1627
Author(s):  
Paul Roots ◽  
Alex Rosenthal ◽  
Yubo Wang ◽  
Fabrizio Sabba ◽  
Zhen Jia ◽  
...  
Keyword(s):  
Retention Time ◽  
Phosphorus Removal ◽  
Energy Recovery ◽  
High Rate ◽  
Stable Operation ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
Solids Retention Time ◽  
Solids Retention ◽  
Biological Phosphorus

Abstract Reducing the solids retention time (SRT) of the enhanced biological phosphorus removal (EBPR) process can increase organic carbon diversion to the sidestream for energy recovery, thereby realizing some of the benefits of the high rate activated sludge (HRAS) process. Determining the washout (i.e. minimum) SRT of polyphosphate accumulating organisms (PAOs), therefore, allows for simultaneous phosphorus and carbon diversion for energy recovery from EBPR systems. However, few studies have investigated the washout SRT of PAOs in real wastewater, and little is known of the diversity of PAOs in high rate EBPR systems. Here we demonstrate efficient phosphorus removal (83% orthophosphate removal) in a high rate EBPR sequencing batch reactor fed real primary effluent and operated at 20 °C. Stable operation was achieved at a total SRT of 1.8 ± 0.2 days and hydraulic retention time of 3.7–4.8 hours. 16S rRNA gene sequencing data demonstrated that Accumulibacter were the dominant PAO throughout the study, with a washout aerobic SRT between 0.8 and 1.4 days. qPCR targeting the polyphosphate kinase gene revealed that Accumulibacter clades IIA, IIB and IID dominated the PAO community at low SRT operation, while clade IA was washed out at the lowest SRT values.

Full Scale Investigations on Enhanced Biological Phosphorus Removal – P-Release in the Anaerobic Reactor

1994 ◽  
Vol 29 (7) ◽  
pp. 153-156 ◽  
Author(s):  
D. Wedi ◽  
P. A. Wilderer
Keyword(s):  
Phosphorus Removal ◽  
Full Scale ◽  
Process Conditions ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
Anaerobic Reactor ◽  
P Release ◽  
Acinetobacter Sp ◽  
Biological Phosphorus ◽  
P Removal

Most of the fundamental processes responsible for enhanced biological phosphorus removal (EBPR) were obtained through laboratory tests under defined conditions with pure or enriched cultures. Acinetobacter sp. was identified as the most important group of bacteria responsible for bio-P removal. Full scale data showed, however, that laboratory results do not match full scale results well enough. There is a lack of data on the effects of sub-optimal process conditions such as inadequate availability of volatile fatty acids (VFA), high nitrate recycle, storm water inflow or low temperatures. In this paper the results of full scale experiments on P-release are presented and compared with theoretical values. Measurements at a full scale Phoredox-system showed a surprisingly low P-release in the anaerobic reactor. Only 4 to 10% of the phosphorus in the activated sludge was released in the bulk liquid. With laboratory batch-tests, a maximum of 20% of the P in the sludge could be released. It is assumed that under the prevailing process conditions either the fraction of Acinetobacter sp. was very small, or bacteria other than Acinetobacter sp. were responsible for the P-removal, or most of the phosphorus was bound chemically but mediated by biological processes.

Enhanced biological phosphorus removal process implemented in membrane bioreactors to improve phosphorous recovery and recycling

2003 ◽  
Vol 48 (1) ◽  
pp. 87-94 ◽  
Author(s):  
B. Lesjean ◽  
R. Gnirss ◽  
C. Adam ◽  
M. Kraume ◽  
F. Luck
Keyword(s):  
Phosphorus Removal ◽  
Theoretical Calculations ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
P Limitation ◽  
Batch Tests ◽  
P Content ◽  
On Line ◽  
Biological Phosphorus ◽  
P Removal

The enhanced biological phosphorus removal (EBPR) process was adapted to membrane bioreactor (MBR) technology. One bench-scale plant (BSP, 200-250 L) and two pilot plants (PPs, 1,000-3,000 L each) were operated under several configurations, including pre-denitrification and post-denitrification without addition of carbon source, and two solid retention times (SRT) of 15 and 26 d. The trials showed that efficient Bio-P removal can be achieved with MBR systems, in both pre- and post-denitrification configurations. EBPR dynamics could be clearly demonstrated through batch-tests, on-line measurements, profile analyses, P-spiking trials, and mass balances. High P-removal performances were achieved even with high SRT of 26 d, as around 9 mgP/L could be reliably removed. After stabilisation, the sludge exhibited phosphorus contents of around 2.4%TS. When spiked with phosphorus (no P-limitation), P-content could increase up to 6%TS. The sludge is therefore well suited to agricultural reuse with important fertilising values. Theoretical calculations showed that increased sludge age should result in a greater P-content. This could not be clearly demonstrated by the trials. This effect should be all the more significant as the influent is low in suspended solids.

Bacteria and Protozoa Population Dynamics in Biological Phosphate Removal Systems

1994 ◽  
Vol 29 (7) ◽  
pp. 109-117 ◽  
Author(s):  
J. S. Čech ◽  
P. Hartman ◽  
M. Macek
Keyword(s):  
Population Dynamics ◽  
Phosphorus Removal ◽  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Sole Source ◽  
Phosphate Removal ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
System Collapse ◽  
Biological Phosphorus

Population dynamics of polyphosphate-accumulating bacteria (PP bacteria) was studied in a laboratory sequencing batch reactor simulating anaerobic-oxic sludge system. The competition between PP bacteria and another microorganism (“G bacteria”) for anaerobic-oxic utilization of acetate as the sole source of organic carbon was observed. The competition was found to be seriously influenced by protozoan and metazoan grazing: Predation-resistant “G bacteria” forming large compact flocs outcompeted PP bacteria. Several breakdowns of enhanced biological phosphorus removal were observed. The first one was related to the development of an euglenid flagellate Entosiphon sulcatus and attached ciliates Vorticella microstoma and V. campanula. The second system collapse was connected with a rapid proliferation of rotifers. An alternative-prey predation was thought to be a mechanism of PP bacteria elimination.

Uncertainty and variability in enhanced biological phosphorus removal (EBPR) stoichiometry: consequences for process modelling and optimization

2010 ◽  
Vol 61 (7) ◽  
pp. 1793-1800 ◽  
Author(s):  
Dwight Houweling ◽  
Yves Comeau ◽  
Imre Takács ◽  
Peter Dold
Keyword(s):  
Phosphorus Removal ◽  
Volatile Fatty Acids ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
Feed Composition ◽  
P Limitation ◽  
Polyphosphate Accumulating Organisms ◽  
Biological Phosphorus ◽  
P Removal

The overall potential for enhanced biological phosphorus removal (EBPR) in the activated sludge process is constrained by the availability of volatile fatty acids (VFAs). The efficiency with which polyphosphate accumulating organisms (PAOs) use these VFAs for P-removal, however, is determined by the stoichiometric ratios governing their anaerobic and aerobic metabolism. While changes in anaerobic stoichiometry due to environmental conditions do affect EBPR performance to a certain degree, model-based analyses indicate that variability in aerobic stoichiometry has the greatest impact. Long-term deterioration in EBPR performance in an experimental SBR system undergoing P-limitation can be predicted as the consequence of competition between PAOs and GAOs. However, the observed rapid decrease in P-release after the change in feed composition is not consistent with a gradual shift in population.

Membrane bioreactor configurations for enhanced biological phosphorus removal

2003 ◽  
Vol 3 (5-6) ◽  
pp. 237-244 ◽  
Author(s):  
C. Adam ◽  
M. Kraume ◽  
R. Gnirss ◽  
B. Lesjean
Keyword(s):  
Phosphorus Removal ◽  
Membrane Bioreactor ◽  
P Uptake ◽  
Raw Water ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
N Removal ◽  
P Content ◽  
Biological Phosphorus ◽  
P Removal

A membrane bioreactor (MBR) bench-scale plant (210 L) was operated under two different enhanced biological phosphorus removal (EBPR) configurations, characterised by pre- and postdenitrification mode. Both configurations were operated at 15 d SRT in parallel to a conventional WWTP and fed with degritted raw water. Effluent PT-concentrations were very stable and low between 0.05-0.15 mg/L for both configurations at sludge P-contents of 2-3%P/TS. In contrast to aerobic P-uptake with postdenitrification anoxic P-uptake clearly dominated in the pre-denitrification configuration. N-removal was surprisingly high with up to 96% in the post-denitrification system without resorting to any carbon addition. During P-spiking (influent: -­40 mgP/L) the P-content increased up to 6-7.5%P/TS. However, a significant amount of P-removal was due to adsorption and precipitation.

Sign in / Sign up

Export Citation Format

Share Document