scholarly journals Integrated Omic Analyses Provide Evidence that a “Candidatus Accumulibacter phosphatis” Strain Performs Denitrification under Microaerobic Conditions

mSystems ◽  
2019 ◽  
Vol 4 (1) ◽  
Author(s):  
Pamela Y. Camejo ◽  
Ben O. Oyserman ◽  
Katherine D. McMahon ◽  
Daniel R. Noguera
Keyword(s):  
Wastewater Treatment ◽  
Energy Use ◽  
Wastewater Treatment Plants ◽  
Cost Effective ◽  
Biological Nutrient Removal ◽  
Nitrogen And Phosphorus ◽  
Biological Removal ◽  
Cost Effective Alternative ◽  
Accumulibacter Phosphatis ◽  
Microaerobic Conditions

“CandidatusAccumulibacter phosphatis” is widely found in full-scale wastewater treatment plants, where it has been identified as the key organism for biological removal of phosphorus. Since aeration can account for 50% of the energy use during wastewater treatment, microaerobic conditions for wastewater treatment have emerged as a cost-effective alternative to conventional biological nutrient removal processes. Our report provides strong genomics-based evidence not only that “Ca. Accumulibacter phosphatis” is the main organism contributing to phosphorus removal under microaerobic conditions but also that this organism simultaneously respires nitrate and oxygen in this environment, consequently removing nitrogen and phosphorus from the wastewater. Such activity could be harnessed in innovative designs for cost-effective and energy-efficient optimization of wastewater treatment systems.

Upgrading Wastewater Treatment Plants for Biological Nutrient Removal

1990 ◽  
Vol 22 (7-8) ◽  
pp. 53-60 ◽  
Author(s):  
B. Rabinowitz ◽  
T. D. Vassos ◽  
R. N. Dawson ◽  
W. K. Oldham
Keyword(s):  
Wastewater Treatment ◽  
Nutrient Removal ◽  
Wastewater Treatment Plants ◽  
Design Flow ◽  
Biological Nutrient Removal ◽  
Nitrogen And Phosphorus ◽  
Conventional Activated Sludge ◽  
Recent Developments ◽  
Removal Technology ◽  
Biological Nitrogen

A brief review of recent developments in biological nitrogen and phosphorus removal technology is presented. Guidelines are outlined of how current understanding of these two removal mechanisms can be applied in the upgrading of existing wastewater treatment plants for biological nutrient removal. A case history dealing with the upgrading of the conventional activated sludge process located at Penticton, British Columbia, to a biological nutrient removal facility with a design flow of 18,200 m3/day (4.0 IMGD) is presented as a design example. Process components requiring major modification were the headworks, bioreactors and sludge handling facilities.

Biological nitrification and denitrification of opto-electronic industrial wastewater

2003 ◽  
Vol 48 (8) ◽  
pp. 27-34 ◽  
Author(s):  
T.-K. Chen ◽  
C.-H. Ni ◽  
J.-N. Chen
Keyword(s):  
Wastewater Treatment ◽  
Industrial Wastewater ◽  
Organic Nitrogen ◽  
Wastewater Treatment Plants ◽  
Biological Nutrient Removal ◽  
Nitrogen And Phosphorus ◽  
Mixed Liquor ◽  
The Past ◽  
Two Factors ◽  
Recycle Rate

Development and application of biological nutrient removal processes accelerated significantly over the past decade due to more stringent nutrients (nitrogen and phosphorus) discharge limits being imposed on wastewater treatment plants. The opto-electronic industry has developed very fast over the past decade in the world. The wastewater often contains a significant quantity of organic nitrogen compounds and has a ratio of over 95% in organic nitrogen (Org-N) to total nitrogen (T-N). In this study, a 2-stage Anoxic/Aerobic pre-denitrification process was established and the efficiency of wastewater treatment was evaluated. Wastewater from an actual LCD-plant was obtained as the sample for looking into the feasibility of opto-electronic industrial wastewater treatment. Hydraulic retention time (HRT) and mixed liquor recycle rate (MLR) were controlled independently to distinguish between the effects of these two factors. Under suitable HRT and mixed liquor recycle ratio, effluents of NH4-N, NOx-N and COD can fall below 20 mg/l, 30 mg/l and 80 mg/l.

scholarly journals Benchmarking biological nutrient removal in wastewater treatment plants: influence of mathematical model assumptions

2012 ◽  
Vol 65 (8) ◽  
pp. 1496-1505 ◽  
Author(s):  
Xavier Flores-Alsina ◽  
Krist V. Gernaey ◽  
Ulf Jeppsson
Keyword(s):  
Wastewater Treatment ◽  
Electron Acceptor ◽  
Nutrient Removal ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Critical Discussion ◽  
Decay Rates ◽  
Biological Nutrient Removal ◽  
Nitrogen And Phosphorus ◽  
Reference Case

This paper examines the effect of different model assumptions when describing biological nutrient removal (BNR) by the activated sludge models (ASM) 1, 2d & 3. The performance of a nitrogen removal (WWTP1) and a combined nitrogen and phosphorus removal (WWTP2) benchmark wastewater treatment plant was compared for a series of model assumptions. Three different model approaches describing BNR are considered. In the reference case, the original model implementations are used to simulate WWTP1 (ASM1 & 3) and WWTP2 (ASM2d). The second set of models includes a reactive settler, which extends the description of the non-reactive TSS sedimentation and transport in the reference case with the full set of ASM processes. Finally, the third set of models is based on including electron acceptor dependency of biomass decay rates for ASM1 (WWTP1) and ASM2d (WWTP2). The results show that incorporation of a reactive settler: (1) increases the hydrolysis of particulates; (2) increases the overall plant's denitrification efficiency by reducing the SNOx concentration at the bottom of the clarifier; (3) increases the oxidation of COD compounds; (4) increases XOHO and XANO decay; and, finally, (5) increases the growth of XPAO and formation of XPHA,Stor for ASM2d, which has a major impact on the whole P removal system. Introduction of electron acceptor dependent decay leads to a substantial increase of the concentration of XANO, XOHO and XPAO in the bottom of the clarifier. The paper ends with a critical discussion of the influence of the different model assumptions, and emphasizes the need for a model user to understand the significant differences in simulation results that are obtained when applying different combinations of ‘standard’ models.

The A–B Process: A Novel two Stage Wastewater Treatment System

1985 ◽  
Vol 17 (2-3) ◽  
pp. 235-246 ◽  
Author(s):  
A. I. Versprille ◽  
B. Zuurveen ◽  
Th Stein
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Reduction Rate ◽  
Cost Effective ◽  
Full Scale ◽  
Treatment System ◽  
Organic Load ◽  
Wastewater Disposal ◽  
Cost Effective Alternative ◽  
Treatment Facilities

New acts on wastewater disposal demand for higher process stability and effluent quality. The A-B process, a novel two step treatment system, meets these requirements in a cost effective way. Five full-scale plants have been put in operation over the last two years. The objective of this paper is to give an outline of the features of the A-B system in the context of the results of these full-scale plants. In spite of the extreme high load, the A-stage can be operated at a high reduction rate and is stable. Variations in the organic load and pH- and toxic shocks are leveled out and a constant, mainly soluble effluent is supplied. This implicates a low sludge production in the B-stage. As a consequence higher overall reduction rates are obtained as compared to conventional processes at the same sludge load. Very low and stable final effluent concentrations are observed in all full-scale plants. Of special interest are the possibilities of upgrading existing conventional treatment facilities, at minor costs, by incorporating the A-B technology. The A-B process therefore can be considered as a very promising, cost effective alternative for both existing and new wastewater treatment plants in responding to the increasing effluent demands.

Denitrification with methanol in tertiary filtration at wastewater treatment plant Zürich-Werdhölzli

1997 ◽  
Vol 36 (1) ◽  
pp. 165-172 ◽  
Author(s):  
G. Koch ◽  
H. Siegrist
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plant ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Cost Effective ◽  
Normal Operation ◽  
Yield Coefficient ◽  
Cost Effective Alternative ◽  
The Eu

In co-ordination with the EU-guidelines the large wastewater treatment plants in Switzerland have to be extended with enhanced nitrogen removal. Denitrification in tertiary filtration is a cost-effective alternative to extended denitrification in the activated sludge system, which needs additional reactor volume. At the wastewater treatment plant Zürich-Werdhölzli full-scale experiments of denitrification with methanol in tertiary filtration were performed during a summer and a winter campaign of 4 months each. For this purpose one of the original 22 filter cells was equipped with a methanol dosage. At temperatures of 12-15°C rates of denitrification of about 1.0 kgN m−3 d−1 are attained. After main backwashing, denitrification is significantly reduced. Frequent backwashings (several times per day) led to methanol breakthroughs due to biofilm loss. The yield coefficient YCOD was 0.4 kg CODX kg−1 CODme. In spite of methanol dosage the quality of the filter effluent was very good during normal operation in the winter campaign. Accumulation of the nitrite intermediate product was observed in summer at temperatures of 20-22°C.

scholarly journals Integrated ‘omic’ analyses provide evidence that aCa. Accumulibacter phosphatis strain performs denitrification under micro-aerobic conditions

2018 ◽  
Author(s):  
Pamela Y. Camejo ◽  
Ben O. Oyserman ◽  
Katherine D. McMahon ◽  
Daniel R. Noguera
Keyword(s):  
Wastewater Treatment ◽  
Phosphorus Removal ◽  
Cost Effective ◽  
Transcript Abundance ◽  
Electron Acceptors ◽  
Nitrogen And Phosphorus ◽  
Aerobic Conditions ◽  
Anoxic Conditions ◽  
Omics Analysis ◽  
Accumulibacter Phosphatis

ABSTRACTThe unique and complex metabolism ofCandidatusAccumulibacter phosphatis has been used for decades for efficiently removing phosphorus during wastewater treatment in reactor configurations that expose the activated sludge to cycles of anaerobic and aerobic conditions. The ability of Accumulibacter to grow and remove phosphorus during cyclic anaerobic and anoxic conditions has also been investigated as a metabolism that could lead to simultaneous removal of nitrogen and phosphorus by a single organism. However, although phosphorus removal under cyclic anaerobic and anoxic conditions has been demonstrated, elucidating the role of Accumulibacter in this process has been challenging, since experimental research describes contradictory findings and none of the published Accumulibacter genomes show the existence of a complete pathway for denitrification. In this study, we use an integrated omics analysis to elucidate the physiology of an Accumulibacter strain enriched in a reactor operated under cyclic anaerobic and micro-aerobic conditions. The reactor’s performance suggested the ability of the enriched Accumulibacter (clade IC) to simultaneously use oxygen and nitrate as electron acceptors under micro-aerobic conditions. A draft genome of this organism was assembled from metagenomic reads (hereafter referred to as Accumulibacter UW-LDO-IC) and used as a reference to examine transcript abundance throughout one reactor cycle. The genome of UW-LDO-IC revealed the presence of a full denitrification pathway. The observed patterns of transcript abundance showed evidence of co-regulation of the denitrifying genes along with acbb3cytochrome, which is characterized as having high affinity for oxygen, thus supporting the hypothesis that UW-LDO-IC can simultaneously respire nitrate and oxygen. Furthermore, we identified an FNR-like binding motif upstream of the coregulated genes, suggesting transcriptional level regulation of the expression of both denitrifying and respiratory pathways in Accumulibacter UW-LDO-IC. Taken together, the omics analysis provides strong evidence that Accumulibacter UW-LDO-IC simultaneously uses oxygen and nitrate as electron acceptors under micro-aerobic conditions.IMPORTANCECandidatusAccumulibater phosphatis is widely found in full-scale wastewater treatment plants, where it has been identified as the key organism for biological removal of phosphorus. Since aeration can account for 50% of the energy use during wastewater treatment, micro-aerobic conditions for wastewater treatment have emerged as a cost-effective alternative to conventional biological nutrient removal processes. Our study provides strong genomics-based evidence that Accumulibacter is not only the main organism contributing to phosphorus removal under micro-aerobic conditions, but also that this organism simultaneously respires nitrate and oxygen in this environment, consequently removing nitrogen and phosphorus from the wastewater. Such activity could be harnessed in innovative designs for cost-effective and energy-efficient optimization of wastewater treatment systems.

Experience with nutrient removal in a fixed-film system at full-scale wastewater treatment plants

1997 ◽  
Vol 36 (1) ◽  
pp. 129-137 ◽  
Author(s):  
Vibeke R. Borregaard
Keyword(s):  
Wastewater Treatment ◽  
Surface Area ◽  
Nutrient Removal ◽  
Wastewater Treatment Plants ◽  
High Specific Surface Area ◽  
Biological Nutrient Removal ◽  
Growth Processes ◽  
Total N ◽  
Attached Growth ◽  
On Line

In the upgrade of wastewater treatment plants to include biological nutrient removal the space available is often a limiting facor. It may be difficult to use conventional suspended growth processes (i.e. activated sludge) owing to the relatively large surface area required for these processes. Recent years have therefore seen a revived interest in treatment technologies using various types of attached growth processes. The “new” attached growth processes, like the Biostyr process, utilise various kinds of manufactured media, e.g. polystyrene granules, which offer a high specific surface area, and are therefore very compact. The Biostyr plants allow a combination of nitrification-denitrification and filtration in one and the same unit. The results obtained are 8 mg total N/l and an SS content normally below 10 mg/l. The plants in Denmark which have been extended with a Biostyr unit have various levels of PLC control and on-line instrumentation.

scholarly journals Biological Nutrient Removal Model No. 2 (BNRM2): a general model for wastewater treatment plants

2013 ◽  
Vol 67 (7) ◽  
pp. 1481-1489 ◽  
Author(s):  
R. Barat ◽  
J. Serralta ◽  
M. V. Ruano ◽  
E. Jiménez ◽  
J. Ribes ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Nitrogen Removal ◽  
Nutrient Removal ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Operating Conditions ◽  
Plant Performance ◽  
Biological Nutrient Removal ◽  
Nitrite Oxidizing Bacteria ◽  
Removal Model

This paper presents the plant-wide model Biological Nutrient Removal Model No. 2 (BNRM2). Since nitrite was not considered in the BNRM1, and this previous model also failed to accurately simulate the anaerobic digestion because precipitation processes were not considered, an extension of BNRM1 has been developed. This extension comprises all the components and processes required to simulate nitrogen removal via nitrite and the formation of the solids most likely to precipitate in anaerobic digesters. The solids considered in BNRM2 are: struvite, amorphous calcium phosphate, hidroxyapatite, newberite, vivianite, strengite, variscite, and calcium carbonate. With regard to nitrogen removal via nitrite, apart from nitrite oxidizing bacteria two groups of ammonium oxidizing organisms (AOO) have been considered since different sets of kinetic parameters have been reported for the AOO present in activated sludge systems and SHARON (Single reactor system for High activity Ammonium Removal Over Nitrite) reactors. Due to the new processes considered, BNRM2 allows an accurate prediction of wastewater treatment plant performance in wider environmental and operating conditions.

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