Effect of solids retention time and wastewater characteristics on biological phosphorus removal

2002 ◽  
Vol 45 (6) ◽  
pp. 137-144 ◽  
Author(s):  
M. Henze ◽  
H. Aspregren ◽  
J. la Cour Jansen ◽  
P.H. Nielsen ◽  
N. Lee
Keyword(s):  
Fatty Acids ◽  
Phosphorus Removal ◽  
Real Life ◽  
Operating Conditions ◽  
Plant Design ◽  
Biological Phosphorus Removal ◽  
Nitrogen And Phosphorus ◽  
Solids Retention ◽  
The One ◽  
Biological Phosphorus

The paper deals with the effect of wastewater, plant design and operation in relation to biological nitrogen and phosphorus removal and the possibilities to model the processes. Two Bio-P pilot plants were operated for 2.5 years in parallel receiving identical wastewater. The plants had SRT of 4 and 21 days, the latter had nitrification and denitrification. The plant with 4 days SRT had much more variable biomass characteristics, than the one with the high SRT. The internal storage compounds, PHA, were affected significantly by the concentration of fatty acids or other easily degradable organics in the wastewater, and less by the plant lay-out. The phosphorus removal is mainly dependent on availability in the wastewater of fatty acids but also by the suspended solids in the effluent, which is higher in the plant with nitrification-denitrification, probably due to a higher SVI or denitrification in the settler. The addition of glucose to the influent seems to have an effect on the performance of the plants similar to that of acetic acid. In spite of great load variations over time to the pilot plants and the different operational modes, the study of population dynamics showed less significant variations with time which has importance in relation to modelling. The overall conclusion of the comparison between the two plants is that the biological phosphorus removal efficiency under practical operating conditions is affected by the SRT in the plant and the wastewater composition. Thus great care should be taken when extrapolating results from one type of plant to another. Indirectly the experiments confirm that results from lab-experiments with artificial wastewater are difficult to extrapolate through modelling to real life wastewater and conditions. The 2.5 years time series can be valuable in verification of models for Nitrogen and Enhanced Biological Phosphorus Removal.

scholarly journals Improving biological phosphorus removal in membrane bioreactors – a pilot study

2013 ◽  
Vol 4 (1) ◽  
pp. 25-33 ◽  
Author(s):  
S. Smith ◽  
G. Kim ◽  
L. Doan ◽  
H. Roh
Keyword(s):  
Pilot Study ◽  
Retention Time ◽  
Phosphorus Removal ◽  
Water Reuse ◽  
Oxygen Demand ◽  
Operating Conditions ◽  
Biological Phosphorus Removal ◽  
Nitrogen And Phosphorus ◽  
N Removal ◽  
Biological Phosphorus

With increasing water reuse applications and possible stringent regulations of phosphorus content in secondary and tertiary effluent discharge in Florida, USA, alternative technologies beyond conventional treatment processes require implementation to achieve low phosphorus (P) and nitrogen (N) concentrations. A pilot scale membrane bioreactor (MBR) system, operated in Florida, adopted the University of Cape Town (UCT) biological process for the treatment of domestic wastewater. The system operated for 280 days at a wastewater treatment facility with total hydraulic retention time (HRT) of 7 h and sludge retention time (SRT) of 20 days. Operating conditions were controlled to maintain specific dissolved oxygen (DO) concentrations in the reactors, operate at suitable return activated sludge (RAS) rates and to waste from the appropriate reactor. This process favored biological phosphorus removal and achieved 94.1% removal efficiency. Additionally, chemical oxygen demand (COD) and N removal were achieved at 93.9% and 86.6%, respectively. Membrane operation and maintenance did not affect the biological P removal performance but enhanced the process given the different operating requirements compared to that required with the conventional UCT process alone. Conclusively, the result of the pilot study demonstrated improvement in biological phosphorus removal. The UCT-MBR process tested achieved average effluent nitrogen and phosphorus concentrations of 5 mg/L as N and 0.3 mg/L as P.

Heterotrophic Kinetic Parameter Estimation for Enhanced Biological Phosphorus Removal Processes Operated in Conventional and Membrane-Assisted Modes

2006 ◽  
Vol 41 (1) ◽  
pp. 72-83 ◽  
Author(s):  
Zhe Zhang ◽  
Eric R. Hall
Keyword(s):  
Parameter Estimation ◽  
Phosphorus Removal ◽  
Growth Yield ◽  
Pilot Scale ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
Nitrogen And Phosphorus ◽  
Parameter Values ◽  
The Impact ◽  
Biological Phosphorus

Abstract Parameter estimation and wastewater characterization are crucial for modelling of the membrane enhanced biological phosphorus removal (MEBPR) process. Prior to determining the values of a subset of kinetic and stoichiometric parameters used in ASM No. 2 (ASM2), the carbon, nitrogen and phosphorus fractions of influent wastewater at the University of British Columbia (UBC) pilot plant were characterized. It was found that the UBC wastewater contained fractions of volatile acids (SA), readily fermentable biodegradable COD (SF) and slowly biodegradable COD (XS) that fell within the ASM2 default value ranges. The contents of soluble inert COD (SI) and particulate inert COD (XI) were somewhat higher than ASM2 default values. Mixed liquor samples from pilot-scale MEBPR and conventional enhanced biological phosphorus removal (CEBPR) processes operated under parallel conditions, were then analyzed experimentally to assess the impact of operation in a membrane-assisted mode on the growth yield (YH), decay coefficient (bH) and maximum specific growth rate of heterotrophic biomass (µH). The resulting values for YH, bH and µH were slightly lower for the MEBPR train than for the CEBPR train, but the differences were not statistically significant. It is suggested that MEBPR simulation using ASM2 could be accomplished satisfactorily using parameter values determined for a conventional biological phosphorus removal process, if MEBPR parameter values are not available.

Saving phosphorus removal at the Henderson NV plant

2012 ◽  
Vol 65 (7) ◽  
pp. 1318-1322 ◽  
Author(s):  
J. Barnard ◽  
D. Houweling ◽  
H. Analla ◽  
M. Steichen
Keyword(s):  
Fatty Acids ◽  
Phosphorus Removal ◽  
Volatile Fatty Acids ◽  
Biological Phosphorus Removal ◽  
Case Histories ◽  
Mixed Liquor ◽  
Removal Process ◽  
Low Levels ◽  
Anaerobic Zone ◽  
Biological Phosphorus

While the mechanism of biological phosphorus removal (BPR) and the need for volatile fatty acids (VFA) have been well researched and documented to the point where it is now possible to design a plant with a very reliable phosphorus removal process using formal flow sheets, BPR is still observed in a number of plants that have no designated anaerobic zone, which was considered essential for phosphorus removal. Some examples are given in this paper. A theory is proposed and then applied to solve problems with a shortage of VFA in the influent of the Henderson NV plant. Mixed liquor was fermented in the anaerobic zone, which resulted in phosphorus removal to very low levels. This paper will discuss some of the background, and some case histories and applications, and present a simple postulation as to the mechanism and efforts at modelling the results.

Biological Phophorus Removal: Study of the Main Parameters

1984 ◽  
Vol 16 (10-11) ◽  
pp. 173-185 ◽  
Author(s):  
D Malnou ◽  
M Meganck ◽  
G M Faup ◽  
M du Rostu
Keyword(s):  
Fatty Acids ◽  
Bacterial Strain ◽  
Phosphorus Removal ◽  
Volatile Fatty Acids ◽  
Organic Substances ◽  
Biological Phosphorus Removal ◽  
Batch Tests ◽  
Microbiological Examination ◽  
Biological Phosphorus ◽  
Phosphorus Storage

The biological phosphorus removal phenomenon has been studied in a modified “Phoredox” type pilot plant. The interpretation of the results obtained was facilitated by batch tests on the sludge. The influence of the duration of anaerobiosis, the presence of nitrates and various organic substances in the anaerobic zone were thus studied successively. The results obtained tend to confirm the hypothesis that biological phosphorus removal is due primarily to the bacterial strain Acinetobacter. Microbiological examination of the sludge has revealed the presence of these bacteria and that of acidogenic bacteria producing volatile fatty acids promoting the growth of Acinetobacter. Pure culture tests have confirmed the possibility of a greater phosphorus storage capability of Acinetobacter.

Background to Biological Phosphorus Removal

1983 ◽  
Vol 15 (3-4) ◽  
pp. 1-13 ◽  
Author(s):  
James L Barnard
Keyword(s):  
Activated Sludge ◽  
Phosphorus Removal ◽  
Plug Flow ◽  
Full Scale ◽  
Biological Phosphorus Removal ◽  
Anaerobic Conditions ◽  
Paper Briefly ◽  
Nitrogen And Phosphorus ◽  
Nitrogen And Phosphorus Removal ◽  
Biological Phosphorus

This paper briefly summarizes the early work on phosphorus removal in activated sludge plants in the U.S.A. and observed that such removals only occurred in low SRT plants of the plug flow type and in the Phostrip plants, neither designed for full nitrification. The discovery of simultaneous nitrogen and phosphorus removal, as well as full-scale experiments are discussed. The Phoredox process was proposed utilizing internal recycling for the removal of nitrates and an anaerobic first stage in which the incoming feed is used to obtain the necessary anaerobic conditions, essential as a conditioning step for the uptake of phosphorus. Proposed mechanisms are discussed.

Development of MBR with reduced operational and maintenance costs

2006 ◽  
Vol 53 (3) ◽  
pp. 53-60 ◽  
Author(s):  
Y. Annaka ◽  
Y. Hamamoto ◽  
M. Akatsu ◽  
K. Maruyama ◽  
S. Oota ◽  
...  
Keyword(s):  
Phosphorus Removal ◽  
Power Demand ◽  
Biological Phosphorus Removal ◽  
Nitrogen And Phosphorus ◽  
Nitrogen And Phosphorus Removal ◽  
Membrane Cleaning ◽  
Sludge Disposal ◽  
Air Supply ◽  
Biological Nitrogen ◽  
Biological Phosphorus

To reduce MBR O&M costs, a new MBR process that conducts efficient simultaneous biological nitrogen and phosphorus removal (BNR) was developed. In the development of this process, various approaches were taken, including reduction of power demand, chemical consumption and sludge disposal costs. To address power demand reductions, air supply requirements for membrane cleaning were reduced. The process adopted an improved membrane that requires less air for cleaning than conventional membranes. It also introduced cyclic aeration, which alternately supplies washing air to the two series of membrane units. Adoption of biological phosphorus removal eliminated chemical costs for phosphorus removal and contributed to the reduction of sludge disposal costs. By combining these technologies, compared to conventional MBR processes, an approximately 27% reduction in O&M costs was achieved.

Comparison of nutrient removal efficiency between pre- and post-denitrification wastewater treatments

2006 ◽  
Vol 53 (9) ◽  
pp. 169-175 ◽  
Author(s):  
K. Hamada ◽  
T. Kuba ◽  
V. Torrico ◽  
M. Okazaki ◽  
T. Kusuda
Keyword(s):  
Nutrient Removal ◽  
Phosphorus Removal ◽  
Biological Nutrient Removal ◽  
Biological Phosphorus Removal ◽  
Nitrogen And Phosphorus ◽  
Nitrogen And Phosphorus Removal ◽  
Nutrient Removal Efficiency ◽  
Polyphosphate Accumulating Organisms ◽  
Biological Phosphorus ◽  
Denitrification Process

A shortage of organic substances (COD) may cause problems for biological nutrient removal, that is, lower influent COD concentration leads to lower nutrient removal rates. Biological phosphorus removal and denitrification are reactions in which COD is indispensable. As for biological simultaneous nitrogen and phosphorus removal systems, a competition problem of COD utilisation between polyphosphate accumulating organisms (PAOs) and non-polyphosphate-accumulating denitrifiers is not avoided. From the viewpoint of effective utilisation of limited influent COD, denitrifying phosphorus-removing organisms (DN-PAOs) can be effective. In this study, DN-PAOs activities in modified UCT (pre-denitrification process) and DEPHANOX (post-denitrification ptocess) wastewater treatments were compared. In conclusion, the post-denitrification systems can use influent COD more effectively and have higher nutrient removal efficiencies than the conventional pre-denitrification systems.

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