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

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.

2018 ◽  
Vol 78 (4) ◽  
pp. 886-895 ◽  
Author(s):  
Yang Pan ◽  
Wenquan Ruan ◽  
Yong Huang ◽  
Qianqian Chen ◽  
Hengfeng Miao ◽  
...  

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.


1994 ◽  
Vol 29 (7) ◽  
pp. 109-117 ◽  
Author(s):  
J. S. Čech ◽  
P. Hartman ◽  
M. Macek

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.


2003 ◽  
Vol 3 (5-6) ◽  
pp. 237-244 ◽  
Author(s):  
C. Adam ◽  
M. Kraume ◽  
R. Gnirss ◽  
B. Lesjean

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.


2001 ◽  
Vol 43 (3) ◽  
pp. 167-174 ◽  
Author(s):  
P. Arnz ◽  
E. Arnold ◽  
P. A. Wilderer

A 17 m3 Sequencing Batch Biofilm Reactor (SBBR) was operated for enhanced biological phosphorus removal and nitrification for a period of 384 days. Enhanced biological phosphorus removal (EBPR) activity was instantly induced after start-up of EBPR operation mode and low phosphate effluent values were reached from the first batch onward. Process stability with regard to nitrification and EBPR were very good although high nitrate loads from backwashing disturbed the P removal performance. Due to anoxic conditions in the beginning of the cycle, readily degradable COD was depleted by denitrification. Consequently, particulate matter was the main carbon source for phosphorus accumulating organisms. Anaerobic hydrolysis or fermentation was found to be the rate limiting process in the SBBR cycle. Simultaneous denitrification occurred in the first 30 minutes of aeration and - to a lesser extent - during the remaining aeration time, enhancing nitrogen removal and indirectly also phosphorus removal.


2011 ◽  
Vol 77 (22) ◽  
pp. 8041-8051 ◽  
Author(s):  
Graciela Gonzalez-Gil ◽  
Christof Holliger

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.


Sign in / Sign up

Export Citation Format

Share Document