Effects of pH on enhanced biological phosphorus removal metabolisms

2002 ◽  
Vol 46 (4-5) ◽  
pp. 171-178 ◽  
Author(s):  
A.J. Schuler ◽  
D. Jenkins
Keyword(s):  
Phosphorus Removal ◽  
Ph Effects ◽  
Batch Reactors ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
Ph Values ◽  
Acetate Uptake ◽  
Batch Tests ◽  
P Release ◽  
Biological Phosphorus

Laboratory-scale sequencing batch reactors exhibiting enhanced biological phosphorus removal were analyzed for pH effects on anaerobic phosphorus (P) release, glycogen degradation, and acetate uptake. Samples with non-soluble P/total suspended solids values of either 0.13-0.14 mg/mg (HP) or 0.065-0.075 mg/mg (LP) were analyzed in anaerobic batch tests with excess acetate addition at pH values ranging from 5.2 to 9.5. A polyphosphate-accumulating metabolism (PAM) had a competitive advantage over a glycogen-accumulating metabolism (GAM) at pH > 7.0. Maximum acetate uptake rates by the HP and LP samples occurred at pH values 8.0 and 6.9, respectively. Anaerobic P release/acetate uptake increased with increasing pH at rates similar to previously reported values. Glycogen degradation/acetate uptake decreased with increasing pH above pH 7, which disagreed with previous reports that glycogen degradation/acetate increased or was unaffected by increasing pH. The results suggested that the acetate uptake mechanisms of GAM and PAM may be different.

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.

Optimising the A/O cycle for phosphorus removal in a submerged biofilter under continuous feed

2000 ◽  
Vol 41 (4-5) ◽  
pp. 503-508 ◽  
Author(s):  
R.F. Gonçalves ◽  
F. Rogalla
Keyword(s):  
Phosphorus Removal ◽  
Organic Substrate ◽  
P Element ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
P Release ◽  
Continuous Feed ◽  
Biological Phosphorus ◽  
Total P ◽  
Selection Of

This work describes laboratory scale research about Enhanced Biological Phosphorus Removal (EBPR) in a submerged biofilter under Anaerobic/Oxic (A/O) alternation and continuous feed. Its main purpose is to detail the behaviour of the reactor throughout the anaerobic and the aerobic phases of the A/O cycle, to study the importance of the anaerobic phase in the selection of the EBPR bacteria in the biofilm and to evaluate the consumption and the importance of the organic substrate during the anaerobic phase. The mass balance over the Phosphorus (P) element indicates that long anaerobic phases (6 h) are more efficient than short ones (3 h) as a selector of EBPR bacteria in biofilms. In both comparisons, thespecific mass of P released in a 6 h period represents almost 50% more than the amount of P release in the shorter period (3 h). However, the presence of rapidly biodegradable COD in the influent of the anaerobic phase is a more effective selector, more important than the duration of the anaerobic phase: by doubling the amount of acetic acid in the influent, a similar 50% increase of P-release can be achieved at short anaerobic periods of 3 h. The effect of the strategy adopted in this study, focusing on selecting EBPR bacteria in biofilm, is shown by the P levels of 4% (total P/SST) in the sludge removed from the BF by backwashing in all periods.

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.

An enhanced biological phosphorus removal (EBPR) control strategy for sequencing batch reactors (SBRs)

2001 ◽  
Vol 43 (3) ◽  
pp. 183-189 ◽  
Author(s):  
C. Y. Dassanayake ◽  
R. L. Irvine
Keyword(s):  
Control Strategy ◽  
Phosphorus Removal ◽  
Batch Reactor ◽  
Past Research ◽  
P Uptake ◽  
Batch Reactors ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
Aeration Time ◽  
Biological Phosphorus

A control strategy was developed for enhanced biological phosphorus removal (EBPR) in a Sequencing Batch Reactor (SBR). Unlike past research that focused on maximizing polyhdroxyalkanoate (PHA) formation during the anaerobic period, this study investigated some of the factors that govern aerobic PHA dynamics and its efficient regulation during phosphate (P) uptake. Influent COD, influent P, and the time for aeration were critical factors that governed PHA use and P uptake during aerated react. Unnecessary PHA oxidation (i.e., in the absence of extracellular P) occurred if the time for aerated react exceeded the time required for P uptake. By adjusting the aeration time to that required for P uptake, residual PHA was sustained in the SBR and excess phosphate uptake reaction potential (PRP) was generated for use during transient influent excursions in P. Unlike space oriented systems, the time for react is simply adjusted in the SBR. Because residual PHA is easily maintained once achieved, high influent COD events can be harnessed to increase or sustain excess PRP for management of expected variations in influent P.

Applicability of experience from laboratory reactors with biological phosphorus removal in full-scale plants

2006 ◽  
Vol 54 (1) ◽  
pp. 267-275 ◽  
Author(s):  
E. Tykesson ◽  
L.L. Blackall ◽  
Y. Kong ◽  
P.H. Nielsen ◽  
J. la Cour Jansen
Keyword(s):  
Phosphorus Removal ◽  
Wastewater Treatment Plants ◽  
In Situ Hybridisation ◽  
Full Scale ◽  
Fluorescence In Situ Hybridisation ◽  
Biological Phosphorus Removal ◽  
Batch Tests ◽  
P Release ◽  
Biological Phosphorus

Enhanced biological phosphorus removal (EBPR) has been used at many wastewater treatment plants all over the world for many years. In this study a full-scale sludge with good EBPR was tested with P-release batch tests and combined FISH/MAR (fluorescence in situ hybridisation and microautoradiography). Proposed models of PAOs and GAOs (polyphosphate- and glycogen-accumulating organisms) and microbial methods suggested from studies of laboratory reactors were found to be applicable also on sludge from full-scale plants. Dependency of pH and the uptake of both acetate and propionate were studied and used for calculations for verifying the models and results from microbial methods. All rates found from the batch tests with acetate were higher than in the batch tests with propionate, which was explained by the finding that only those parts of the bacterial community that were able to take up acetate anaerobically were able to take up propionate anaerobically.

The effect of fermentation products on enhanced biological phosphorus removal, polyphosphate storage, and microbial population dynamics

1994 ◽  
Vol 30 (6) ◽  
pp. 213-219 ◽  
Author(s):  
A. A. Randall ◽  
L. D. Benefield ◽  
W. E. Hill
Keyword(s):  
Population Dynamics ◽  
Carboxylic Acids ◽  
Phosphorus Removal ◽  
Microbial Population ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
Fermentation Products ◽  
Batch Tests ◽  
Glucose System ◽  
Biological Phosphorus

Using anaerobic/aerobic sequencing batch reactors (SBRs) it was found that pre-fermentation of influent glucose resulted in a microbial population capable of enhanced biological phosphorus removal (EBPR). Batch tests indicated the C1-C5 carboxylic acids, except propionate, typically improved phosphorus removal. Branched molecules were superior to their linear isomers. The C1-C5 alcohols did not affect removal. Glucose, propionate, and an amino-acid rich substrate were detrimental. Using NMR spectroscopy it was observed that intracellular forms and locations of phosphorus did not change regardless of the substrate received. Polyphosphate (polyP) was present throughout the cells at the end of aerobiosis. It then degraded to inorganic phosphate via a zero-order enzymatic reaction concentrated at the cell membrane. An anaerobic/aerobic SBR receiving starch, rather than glucose fermentation products, showed only marginal EBPR and did not respond to carboxylic acids or other substrates in batch tests. Pseudomonas and Bacillus were numerous in the glucose system but were not isolated from the starch system. Aeromonas were dominant in the starch system. Although the glucose system showed better phosphorus removal than the starch system, it also showed greater variability. Phosphorus removal varied in a chaotic, but bounded, manner, probably due to population dynamics.

scholarly journals Dynamics of Microbial Community Structure of and Enhanced Biological Phosphorus Removal by Aerobic Granules Cultivated on Propionate or Acetate

2011 ◽  
Vol 77 (22) ◽  
pp. 8041-8051 ◽  
Author(s):  
Graciela Gonzalez-Gil ◽  
Christof Holliger
Keyword(s):  
Phosphorus Removal ◽  
Bubble Column ◽  
Phosphate Removal ◽  
Batch Reactors ◽  
Type I ◽  
Aerobic Granules ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
Content Type ◽  
Biological Phosphorus

ABSTRACTAerobic granules are dense microbial aggregates with the potential to replace floccular sludge for the treatment of wastewaters. In bubble-column sequencing batch reactors, distinct microbial populations dominated propionate- and acetate-cultivated aerobic granules after 50 days of reactor operation when only carbon removal was detected. Propionate granules were dominated byZoogloea(40%),Acidovorax, andThiothrix, whereas acetate granules were mainly dominated byThiothrix(60%). Thereafter, an exponential increase in enhanced biological phosphorus removal (EBPR) activity was observed in the propionate granules, but a linear and erratic increase was detected in the acetate ones. BesidesAccumulibacterandCompetibacter, other bacterial populations found in both granules were associated withChloroflexusandAcidovorax. The EBPR activity in the propionate granules was high and stable, whereas EBPR in the acetate granules was erratic throughout the study and suffered from a deterioration period that could be readily reversed by inducing hydrolysis of polyphosphate in presumably saturatedAccumulibactercells. Using a newppk1gene-based dual terminal-restriction fragment length polymorphism (T-RFLP) approach revealed thatAccumulibacterdiversity was highest in the floccular sludge inoculum but that when granules were formed, propionate readily favored the dominance ofAccumulibactertype IIA. In contrast, acetate granules exhibited transient shifts between type I and type II before the granules were dominated byAccumulibactertype IIA. However,ppk1gene sequences from acetate granules clustered separately from those of propionate granules. Our data indicate that the mere presence ofAccumulibacteris not enough to have consistently high EBPR but that the type ofAccumulibacterdetermines the robustness of the phosphate removal process.

Competition between polyphosphate- and glycogen-accumulating organisms in biological phosphorus removal systems – effect of temperature

2002 ◽  
Vol 46 (1-2) ◽  
pp. 191-194 ◽  
Author(s):  
L.-M. Whang ◽  
J.K. Park
Keyword(s):  
High Temperatures ◽  
Uptake Rate ◽  
Phosphorus Removal ◽  
Effect Of Temperature ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
Batch Studies ◽  
Acetate Uptake ◽  
Polyphosphate Accumulating Organisms ◽  
Biological Phosphorus

This study demonstrated that temperature is an important factor in determining the outcome of competition between polyphosphate-accumulating organisms (PAOs) and glycogen-accumulating non-poly-P organisms (GAOs) and the resultant stability of enhanced biological phosphorus removal (EBPR) systems. At 20°C and a 10-day sludge age, PAOs were dominant in the anaerobic/aerobic (A/O) SBR, however, at 30°C and a 10-day sludge age, GAOs were dominant in the A/O SBR. For kinetic batch studies, the anaerobic specific acetate uptake rate of GAO-dominated sludge (1.34 × 10−3 mg C/mg VSS·minute) was higher than the rate of PAO-dominated sludge (0.89 × 10−3 mg C/mg VSS·minute) at 30°C, leading to the eventual failure of EBPR processes at high temperatures.

scholarly journals Performance of enhanced biological phosphorus removal and population dynamics of phosphorus accumulating organisms in sludge-shifting sequencing batch reactors

2018 ◽  
Vol 78 (4) ◽  
pp. 886-895 ◽  
Author(s):  
Yang Pan ◽  
Wenquan Ruan ◽  
Yong Huang ◽  
Qianqian Chen ◽  
Hengfeng Miao ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Phosphorus Removal ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Batch Reactor ◽  
Batch Reactors ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
High Concentration ◽  
Gradient Gel Electrophoresis ◽  
Biological Phosphorus

Abstract The sludge-shifting sequencing batch reactor (SBR) is an enhanced biological phosphorus removal (EBPR) process for wastewater treatment. In this study, the enrichment of phosphorus accumulating organisms (PAOs) will be attempted by using different high concentration of substrates. In sludge-shifting SBR, activated sludge can be continuously shifted from the bottom of SBR to anaerobic zone/selector, which contains high concentration of substrates, through an orderly reflux between the paralleled SBRs. Denaturing gradient gel electrophoresis (DGGE) methods were used to monitor microbial diversity in sludge. Fluorescence in situ hybridization (FISH) was used to determine the microbial population profile and distribution map under different sludge shifting volumes. The synthesis of intracellular polymers in this process was also analyzed. Phosphorus removal efficiency as high as 96% ± 1.3% was achieved under a sludge shifting ratio of 30%. Synthetic efficiencies of polyhydroxybutyrate (PHB) by PAOs were improved at high sludge shifting ratios. FISH results demonstrated that the population of PAOs in the process increased under properly sludge shifting ratio and it significantly improved phosphorus removal efficiency. Sequencing results indicated that determined sequences (11 OTUs) belonged to Proteobacterium, Actinobacteria and Firmicutes, Pseudomonas kuykendallii, which played an important role in the process of P removal.

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