Dissertations / Theses: 'Enhanced biological phosphorus removal (EBPR)'

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Chan, Pacheco Carlos Roberto. "Integrating enhanced biological phosphorus removal (EBPR) in a resource recovery scenario." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/666850.

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La presente tesis doctoral se enfoca en evaluar un sistema de eliminación biológica de fósforo (enhanced biological phosphorus removal, EBPR) orientado a un escenario de recuperación de recursos. Los resultados obtenidos se dividieron en cuatro capítulos, los cuales aparecen en los capítulos 4, 5, 6 y 7. Los temas estudiados en cada capítulo se resumen a continuación: Capítulo 4. Se estudió a largo plazo un sistema SBR-EBPR cuya configuración fue modificada con la finalidad de obtener un líquido altamente enriquecido con P. La configuración del sistema SBR-EBPR consistió en incluir una etapa de extracción de sobrenadante al final de la etapa anaeróbica (después de un periodo de sedimentación). El líquido extraído tiene la mayor concentración de P en el ciclo SBR, lo cual implica que la disponibilidad de este nutriente estaría limitada para los requerimientos metabólicos de los microrganismos responsables de este proceso, comprometiendo la eficiencia del proceso EBPR. Por ello se evaluaron diferentes volúmenes de extracción. Capítulo 5. Se estudió el comportamiento de la actividad EBPR usando tiempos de retención celular (TRC) cortos, esto con la finalidad de evaluar su posible integración en sistemas energéticamente eficientes, como el proceso A/B. Con este fin, se operaron tres diferentes reactores secuenciales (por lotes) con una configuración convencional a 25 ºC y a TRC de entre 3-14 días. Capítulo 6. La influencia de la temperatura y el SRT sobre el proceso EBPR fueron evaluadas, a corto y largo plazo. En este capítulo se usaron tres sistemas EBPR, los cuales se operaron a temperaturas de entre 10-20 ºC y a TRC de entre 3.5-15 días. Capítulo 7. La biomasa obtenida de los diferentes sistemas (SBR-EBPR), usados en el capítulo 6 se metió a pruebas de digestión anaerobia, esto con la finalidad de evaluar su potencial de producción de metano. Debido a que cada biomasa contenía diferentes concentraciones de PHA, la influencia del contenido de PHA sobre la de producción de metano también fue evaluada.
This doctoral thesis focuses on evaluating an EBPR (enhanced biological phosphorus removal process) system oriented to the scenario of resource recovery. The results obtained are divided into four chapters, which are presented in chapters 4, 5, 6 and 7. The topics studied in each chapter are summarized below: Chapter 4. A SBR-EBPR system was studied in the long term by modifying its configuration in order to obtain an anaerobic supernatant enriched in phosphorus. The configuration of system SBR-EBPR included one stage for the extraction of supernatant at the end of anaerobic stage (after a period of sedimentation). The extracted liquid has the largest concentration of P in the SBR cycle, which implies that the availability of this nutrient would be limited for the metabolic requirements of the PAO, compromising the efficiency of the process EBPR. For this reason, different extraction volumes were assessed. Chapter 5. The behavior of the EBPR activity using short cell retention times (SRT) was studied in order to assess the possibility of its integration to energetically efficient systems, such as the A/B process. With this purpose, different SBR were operated with a conventional configuration. These SBR were operated at 25 °C and at 3-14 days SRT. Chapter 6. the influence of temperature and SRT on the EBPR process was assessed (in both the short and long terms) using three EBRP systems. These systems were operated at t temperatures between 10-20 ºC and at TRC between 3.5-15 days. Chapter 7. The biomass obtained in the different operational periods of the SBR-EBPR systems used in chapter 6 was subjected to an anaerobic digestion test to evaluate its methane production. Because each biomass contained different concentrations of PHA, the influence of PHA content on methane production was also evaluated.

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Cope, Helen Anne. "Raman spectroscopy as a tool to improve Enhanced Biological Phosphorus Removal." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/25487.

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Enhanced Biological Phosphorus Removal (EBPR) is an established process in wastewater treatment that uses bacteria to reduce phosphorus levels below regulatory discharge limits. Recently, in light of growing political concern over phosphorus sustainability, EBPR has also been recognised as a platform from which phosphorus may be recovered and recycled onto land as fertiliser. Operating EBPR to optimise performance and efficiency is therefore extremely important, but remains a challenge due to poor understanding of these bacterial ecosystems. Raman spectroscopy is a non-invasive, label-free, culture-independent technique capable of analysing live, single cells. Despite its advantages, Raman spectroscopy has been applied to study EBPR bacteria in just a handful of studies and thus has a low profile in this field of research. More work is required to investigate potential areas of application for Raman spectroscopy in EBPR research. The principal thesis presented here is that Raman spectroscopy could be used as a tool to improve EBPR. The Raman spectra used for this investigation were acquired from individual EBPR bacteria dried onto a calcium fluoride substrate. The bacterial samples were collected from three different sources, namely lab-scale sequencing batch reactors located in Edinburgh (University of Edinburgh, UK) and Boston (Northeastern University, USA), and a full-scale EBPR plant in Slough (Thames Water, UK). Using these spectra, some potential applications and limitations of Raman spectroscopy for improving EBPR were explored. In this foundation work, a particular emphasis on spectral analysis methods was kept in light of the benefits of automating analysis as well as the need for standardisation to be able to compare results between different studies and groups. Nine methods were compared for baselining Raman spectra of individual EBPR bacteria. From these, the “small-window moving average” (SWiMA) method was determined to be the best baselining technique for our purposes at the current time. In agreement with earlier studies, the Raman spectroscopic signatures of three key EBPR metabolites – polyphosphate, polyhydroxyalkanoate (PHA) and glycogen – were shown to be clearly identifiable in individual EBPR bacteria when present. The Raman shifts of characteristic spectral bands arising from polyphosphate were shown to vary significantly between samples and the implications of this were discussed. Examples of how the Raman spectra of individual bacteria can be modelled with multivariate tools to open up new areas for research were given. MCR modelling was demonstrated to offer a novel way to normalise the Raman spectra of individual EBPR bacteria prior to quantitative analysis. With the instrumental set-up in this work, the limit of detection (LOD) of aqueous polyphosphate samples was estimated to be approximately 0.08 M and 0.02 M for 10 second and 200 second acquisitions respectively. Future work is required to research ways in which a more comparable form of polyphosphate ‘standard’ might be prepared so that direct correlation can be drawn between measurements made on such a standard and measurements made in bacterial cells. Overall, several applications and challenges of Raman spectroscopy for the investigation of EBPR bacteria are presented in this work together with recommendation for how to process the spectral data. The conclusions drawn from this work indicate that Raman spectroscopy could be used as a tool to improve EBPR but further work is required to refine and apply these methods.

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malekjahani, seyed. "THE EFFECTS OF PH ON ENHANCED BIOLOGICAL PHOSPHORUS REMOVAL (EBPR) WITH PROPIONIC ACID AS THE DOMINANT VOLATILE FATTY ACID (VFA)." Master's thesis, University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3712.

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pH control is a tool to improve some aspects of Enhanced Biological Phosphorus Removal (EBPR) process. Filipe et al (2001a, 2001b, and 2001c) found strong evidence that the stability of EBPR systems can be improved by increasing the pH of the anaerobic zone, thereby creating conditions where phosphorus-accumulating organisms (PAOs) are able to take up acetate faster than glycogen-accumulating organisms (GAOs). They explained this observation by comparing the growth rate of phosphorus-accumulating organisms (PAOs) and glycogen-accumulating organisms (GAOs) and found that pH has little effect on PAOs growth rate but adversely affects GAOs growth rate when it increases (at pH values greater than 7.25, PAOs would take acetate faster than GAOs would). They used synthetic wastewater rich in acetic acid. In this study, we used real wastewater and the dominant volatile fatty acid available to microorganisms was propionic acid in continuous EBPR system. It was found that lower anaerobic zone pH (6.5 vs. 7.2) reduced the anaerobic P release both on an MLVSS specific basis and also on a non-specific (absolute value for the process) basis. In addition, the observed yield was significantly decreased. Aerobic P uptake was lower in the low-pH system (on a non-specific basis) due to the lower observed yield, and thus lower MLVSS concentration. Net P uptake was hard to interpret because of the effect of P release in the secondary clarifier of Train 2 (high pH). However, on a specific basis it was clear that net P uptake was either equal or better in the low-pH system regardless of how the secondary clarifier data was interpreted. Carbon transformations were not impacted in as consistent a fashion as anaerobic P release was. On a specific basis, PHA content remained unchanged although the PHV/PHB ratio was impacted with much lower PHV content in the low-pH system. Glycogen content and the amount of labile glycogen (delta glycogen) were higher in the low-pH system, in spite of the fact that MLVSS P content did not decrease. However, due to the impact of the low observed yield at low pH, absolute values resulted in higher PHA content for the process reactors as a whole, higher glycogen content, and unchanged labile glycogen. Low pH resulted in increased biomass P content, however the lower observed yield offset this on a process basis so that effluent P levels were nearly equal. So low pH improved P removal on a specific basis, but not on a process basis. Since it is unknown if the low observed yield is repeatable, and due to the impact of the secondary clarifier in the high pH system, it cannot be concluded that the effect of low pH on net P removal would be similar in other EBPR systems.
M.S.Env.E.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Environmental Engineering

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Costa, Giuseppe Alessio. "Implementation of enhanced biological phosphorus removal (ebpr) wastewater treatment processes enriched with different microbial communities." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/8017/.

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The EBPR (Enhanced Biological Phosphorus Removal) is a type of secondary treatment in WWTPs (WasteWater Treatment Plants), quite largely used in full-scale plants worldwide. The phosphorus occurring in aquatic systems in high amounts can cause eutrophication and consequently the death of fauna and flora. A specific biomass is used in order to remove the phosphorus, the so-called PAOs (Polyphosphate Accumulating Organisms) that accumulate the phosphorus in form of polyphosphate in their cells. Some of these organisms, the so-called DPAO (Denitrifying Polyphosphate Accumulating Organisms) use as electron acceptor the nitrate or nitrite, contributing in this way also to the removal of these compounds from the wastewater, but there could be side reactions leading to the formation of nitrous oxides. The aim of this project was to simulate in laboratory scale a EBPR, acclimatizing and enriching the specialized biomass. Two bioreactors were operated as Sequencing Batch Reactors, one enriched in Accumulibacter, the other in Tetrasphaera (both PAOs): Tetrasphaera microorganisms are able to uptake aminoacids as carbon source, Accumulibacter uptake organic carbon (volatile fatty acids, VFA). In order to measure the removal of COD, phosphorus and nitrogen-derivate compounds, different analysis were performed: spectrophotometric measure of phosphorus, nitrate, nitrite and ammonia concentrations, TOC (Total Organic Carbon, measuring the carbon consumption), VFA via HPLC (High Performance Liquid Chromatography), total and volatile suspended solids following standard methods APHA, qualitative microorganism population via FISH (Fluorescence In Situ Hybridization). Batch test were also performed to monitor the NOx production. Both specialized populations accumulated as a result of SBR operations; however, Accumulibacter were found to uptake phosphates at higher extents. Both populations were able to remove efficiently nitrates and organic compounds occurring in the feeding. The experimental work was carried out at FCT of Universidade Nova de Lisboa (FCT-UNL) from February to July 2014.

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Balaguer-Barbosa, Maraida. "Recovery of Nutrients from Anaerobically Digested Enhanced Biological Phosphorus Removal (EBPR) Sludge through Struvite Precipitation." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7471.

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Water resources in Florida have been severely degraded by eutrophic conditions, resulting toxic algae blooms, which negatively affect health and tourism. Eutrophication, or excessive amount of phosphorus (P) and nitrogen (N) in water, overstimulates the production of aquatic plants, depletes dissolved oxygen, and deteriorates the aquatic environment. However, phosphorus is a non-renewable resource essential for all living organisms. In fact, more than half of the total demand for P globally is to supply the food industry, which has concerningly accelerated the depletion rates of phosphate reserves. In many wastewater treatment plants (WWTPs), the enhanced biological phosphorus removal (EBPR) approach has been employed to achieve high phosphorus removals from wastewater through phosphate-accumulating organisms (PAOs). However, during either anaerobic or aerobic digestion of EBPR sludge, stored polyphosphates are released and carried into the sidestream, which is typically returned to the headworks of the main treatment facility, thereby recycling phosphorus back into the system. This treatment train is highly inefficient because nutrients rather are recirculated rather than recovered. Struvite (MgNH4PO4•6H2O) is precipitated in oversaturated aqueous solutions with equal molar concentrations of magnesium, ammonium, and phosphate. The controlled crystallization of struvite may be applied to remove phosphorus and some ammonium from sidestreams, which is the liquid portion of the digester effluent. Struvite can be employed as a sustainable slow-release fertilizer due to its low solubility in water. This offers the opportunity of marketing the struvite produced under controlled conditions and creating a revenue for the utility. The specific research objectives of this thesis are (1) to investigate different possible operating conditions under which anaerobically digested sludge from EBPR facilities might be treated through struvite precipitation; (2) to quantify the removal of N and P from sidestreams from anaerobically digested EBPR sludge via struvite precipitation and assess the composition of the precipitate obtained; and (3) to generate a cost analysis to assess the trade-offs between the capital and operation and maintenance (O&M) costs of struvite production and the benefits such as reduced chemical use and production of a slow-release fertilizer. The main parameters affecting struvite precipitation are the Mg2+ to PO43- molar ratio, pH, temperature, mixing speed, hydraulic retention time (HRT), and the seed quantity added to promote nucleation. Different operating conditions within these parameters were batch-tested as part of this study using sidestream from the pilot-scale anaerobic digester (AD) fed from Falkenburg Advanced Wastewater Treatment Plant (FAWWTP) EBPR sludge. Additionally, the effect of temperature and pH were investigated using Visual MINTEQ simulations. Analysis of Variance (ANOVA) was employed to investigate the variance within the removals from the centrate obtained for phosphate, ammonium, magnesium, and calcium. The chemical composition of the solids collected after employing the selected operating conditions was analyzed by powder X-ray diffraction (PXRD). The results for the batch tests performed as part of this thesis were quantified in terms of the removals of phosphate, ammonium, magnesium, and calcium from the centrate. The greatest amount of phosphate removal was achieved by operating the struvite reactor at 4.0 mmol of Mg2+ per mmole of PO43-. The other molar ratios tested were 1.0, 2.0, and 3.0. Visual inspection of the data showed significant variability in removals of ammonium, calcium, and magnesium, which are likely to be correlated with the highly variable influent concentrations into the struvite reactor. In this case, ANOVA will require larger data sets to accurately analyze variance in the results. The statistical results given by ANOVA for the pH suggests that the main species to contribute with struvite being precipitated are statistically stable within the tested pH values of 8.5, 9.0, and 9.5. The results obtained by the simulation using Visual MINTEQ indicated that maximum saturation as function of pH takes place at a pH between 9.5 and 10.0. The ANOVA for the mixing speed showed that significant amounts of ammonium were removed at higher mixing speeds. This is likely due ammonium being volatilized, which is enhanced by turbulence. Magnesium and phosphate showed lower removals at higher mixing speeds, suggesting that too high mixing speeds will promote struvite seed dissolution. ANOVA identified NH4+ and Ca2+ as the species significantly impacted by modifying the HRT from 8 to 20 minutes. This suggests that prolonged HRT promotes inorganic nitrogen species to volatilize. It is likely that at higher HRT, tricalcium phosphates (TCP) or other favored calcium species coprecipitated together with struvite. Regarding the added struvite seed for nucleation, the greatest removals of ammonium, magnesium, and, phosphate were observed when 1g/L of struvite seed was added. The results also indicated that adding 5 and 10 g/L was an excessive amount of seed, which ended up contributing significantly to more nutrients into the centrate rather than precipitating them. The results also suggested that the struvite crystals formed in the sidestream by secondary nucleation, since removals close to zero were reached after adding no seed. The optimum temperature identified by the simulation in Visual MINTEQ was 21°C. Operating the struvite reactor under the optimal conditions identified in the batch tests, resulted in an average of 99% total P (TP) and 17% total N (TN) removals. The precipitate molar composition for [Mg2+:NH4+:PO43-] was equal to [2:2:1] based on the concentrations that disappeared from the aqueous solution, suggesting that other minerals coprecipitated with struvite. Visual MINTEQ predicted that together with struvite, CaHPO4 and CaHPO4•2H2O will also precipitate under the tested conditions. However, given the obtained ratio it is likely that other unpredicted species by Visual MINTEQ, such as magnesium carbonates or magnesium hydroxide coprecipitated with struvite. PXRD analysis also revealed that the sample was likely contaminated struvite, although the specific contaminants were not identified. A cost analysis was performed to distinguish the economic feasibility of incorporating a struvite harvesting system to treat the anaerobically digested sidestream from the Biosolids Management Facility (BMF) within the Northwest Regional Water Reclamation Facility (NWRWRF). Three different scenarios were evaluated; in Scenario (1) Ostara® Nutrient Recovery Technologies Inc. (Ostara®) evaluated the production of struvite from anaerobically digested EBPR sidestream using a fluidized reactor. In Scenario (2), Ostara® evaluated the production of struvite in a fluidized bed reactor by employing Waste Activated Sludge Stripping to Remove Internal Phosphorus (WASSTRIP™) in a mixture of post-anaerobic digestion centrate and pre-digester thickener liquor. Scenario (3) was addressed by Schwing Bioset Inc. (SBI) for a continuously-stirred reactor followed by a struvite harvesting system. Scenario (2) offers the highest TP and TN recoveries through WASSTRIP™ release due to the additional mass of phosphorus that is sent to the phosphorus recovery process. Therefore, although Scenario (2) has the highest total capital costs ($5M) it also has the shortest payback period (18 years). Scenarios (1) and Scenario (3) have similar payback periods (22-23 years) but very different total capital costs. The annual savings by producing struvite in Scenario (3) is $40K, which is about 30% less than producing struvite in Scenario (1). This is probably because the only savings considered under Scenario (3) were the lower alum usage and the fertilizer revenue; however, the savings by producing class A biosolids, were not accounted for. Consequently, the reduced total capital cost of $960K and the annual payment amount per interest period close to $80K, positioned Scenario (3) as the more feasible one, considering 20 years as the expected life of the asset at a 5% interest rate.

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Pijuan, Vilalta Maite. "Effect of different carbon sources and continuous aerobic conditions on the EBPR process." Doctoral thesis, Universitat Autònoma de Barcelona, 2004. http://hdl.handle.net/10803/5300.

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Magro, Daniel. "EFFECTS OF REDUCED RAS AND VOLUME ON ANAEROBIC ZONE PERFORMANCE FOR A SEPTIC WASTEWATER BIOLOGICAL PHOSPHOROUS REMOVAL SYSTEM." Master's thesis, University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2964.

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Enhanced Biological Phosphorous Removal (EBPR) performance was found to be adequate with reduced Return Activated Sludge (RAS) flows (50% of available RAS) to the anaerobic tank and smaller than typical anaerobic zone volume (1.08 hours hydraulic retention time or HRT). Three identical parallel biological nutrient removal (BNR) pilot plants were fed with strong, highly fermented (160 mg/L VFAs), domestic/industrial wastewater from a full scale wastewater treatment facility (WWTF). The pilot plants were operated at 100%, 50%, 40% and 25% RAS (percent of available RAS) flows to the anaerobic tank with the remaining RAS to the anoxic tank. In addition, varying anaerobic HRT (1.08 and 1.5 hours), and increased hydraulic loading (35% increase) was examined. The study was divided in four Phases, and the effect of these process variations on EBPR were studied by having one different variable between two identical systems. The most significant conclusions were that only bringing part of the RAS to the anaerobic zone did not decrease EBPR performance, instead changing the location of P release and uptake. Bringing less RAS to the anaerobic and more to the anoxic tank decreased anaerobic P release and increased anoxic P release (or decreased anoxic P uptake). Equally important is that with VFA rich influent wastewater, excessive anaerobic volume was shown to hurt overall P removal even when it resulted in increased anaerobic P release. Computer modeling with BioWin and UCTPHO was found to predict similar results to the pilot test results. Modeling was done with reduced RAS flows to the anaerobic zone (100%, 50%, and 25% RAS), increased anaerobic volume, and increased hydraulic loading. The most significant conclusions were that both models predicted EBPR did not deteriorate with less RAS to the anaerobic zone, in fact, improvements in EBPR were observed. Additional scenarios were also consistent with pilot test data in that increased anaerobic volume did not improve EBPR and increased hydraulic loading did not adversely affect EBPR.
M.S.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Environmental Engineering

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Santos, Jorge Miguel Martins. "Understanding the microbial ecology and ecophysiology of enhanced biological phosphorus removal processes through metabolic modelling and experimental studies." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/12214.

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Dissertation to obtain the degree of Master in Chemical and Biochemical Engineering
The enhanced biological phosphorus removal (EBPR) process in activated sludge systems has become a widely applied wastewater treatment technology to control eutrophication. The success of this process relies on the sludge enrichment with polyphosphate accumulating organisms (PAOs), while one of the main causes for its failure is due to microbial competition between PAOs and another group of organisms known as the glycogen accumulating organisms (GAOs). The microbial ecology and ecophysiology of these two groups have been investigated through metabolic modelling and experimental studies in order to provide a better understanding of EBPR systems. This thesis focuses on researching the P removal efficiency and metabolic behaviour of an enriched culture containing two PAOs: Tetrasphaera-related organisms and Accumulibacter, which were acclimatized with casamino acids as sole carbon source in a sequencing batch reactor (SBR). Both organisms were identified through fluorescence in situ hybridization (FISH), and this culture demonstrated anaerobic P release, glycogen hydrolysis, a very low poly--hydroxyalkanoates (PHA) synthesis and high casamino acids uptake; followed by aerobic P uptake, glycogen formation and a very low PHA oxidation. Different carbon sources (glucose, acetate, propionate, glutamate, aspartate, glycine and casamino acids) were studied through batch tests inoculated with sludge from the main SBR. Through experimental data, it was suggested that Accumulibacter were responsible for the uptake of volatile fatty acids (VFAs), and Tetrasphaera-related organisms were likely responsible for both glucose and amino acids uptake. This thesis also focuses on the development of a model that combines a PAO-GAO metabolic model with activated sludge model no. 2d (ASM2d) in collaboration with Hydromantis Environmental Software Solutions, Inc.. The combined model was implemented in the GPS-X software and will provide a new and advanced platform for wastewater treatment modelling, which will be available to practitioners.

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Van, Lierde Patrick G. "Nucleation, milk and membranes as modifications to enhance biological phosphorus removal in activated sludge." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/16784.

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Enhanced biological phosphorus removal (EBPR) was researched from the performance of a modified University of Cape Town (UCT), anaerobic-anoxic/nitrifying-aerobic process. The work focussed on high P influent where milk was compared to carbohydrates as exogenous added carbon and typical settled sewage. The results confirmed that at equal COD load in the influent (minimum COD:P (250:5) ratio for EBPR), milk always provided sufficient soluble substrate than the carbohydrate mix, but also improved the EBPR performance. The laboratory scale treated 10L/day where 2 parallel treatment trains for milk and an equivalent carbohydrate mix as supplement to compare and study the P sequestration from hypothesised P ligands in milk and easily assimilable carbon (AOM) after fermentation for biological P uptake. The aerobic bioreactors used submerged flat sheet membranes (AeMBR) to improve the effluent quality and reduce the suspended solid residues. The results suggested extra benefits from adding calcium chloride (CaCl2) (200 ml at 250 mM/day or 200 mg/L treated) to form P complexes both in the anaerobic and aerobic zones (100 ml CaCl2 250mM/zone/day). To complete P removal a calcium phosphate (CaPO4) further treatment stage (post membrane final effluent (F.E.)) was added for nucleation. The combination of, A2O-N, exogenous carbon and calcium addition improved the performance of the EBPR, and enabled the laboratory units to achieve less than the 1 mg/L P required by the EU Directive. The process was tested at higher than normal P loads (maximum 100 mg/L) (domestic wastewater influent 15 mg/L). Experiments with influent P load ≤ 50mg/L, with 1% milk as AOM were compared to the carbohydrate mix and could remove soluble P to less than 1mg/L above 97% and less than 2 mg/L more than 99% of the in the time respectively. With an influent P load of 60mg/L (maximum 100 mg/L), the soluble P in the F.E. with milk was below 5 mg/L and below 8 mg/L with carbohydrates mix. The results showed that most of the phosphorus was retained by the sludge during the anoxic-aerobic phases. The remaining phosphate in the F.E. was able to pass through AeMBR pore size (0.4 μm) and needed to be chelated by the nucleation process. The results indicated this A2O-N modifications achieved stable nutrient removal and also offered the potential for more sustainable phosphorus recovery. The EBPR without AOM was 25% less efficient compared to milk and never achieved the E.U standard of 1mg/L in final effluent. The flat sheet membrane always achieved a NTU final effluent below 1 and the TOC always greater than 90% removal or less than the EU 125 standard regardless of the feeding COD/P ratio.

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Kumpulainen, Eva. "Utvärdering och optimering av sidoströmshydrolysen vid Duvbackens reningsverk." Thesis, Uppsala universitet, Avdelningen för systemteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-206102.

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I Sverige förekommer strikta krav på fosforrening av avloppsvatten och detta har bidragit till att kemisk fällning har kommit att dominera som reningsmetod för fosfor vid svenska avloppsreningsverk. Fällningskemikalier är dyrt för reningsverken att köpa in och ger negativ påverkan på miljön vid tillverkning och transport. Strängare reningskrav har ökat behovet av nya reningsmetoder som på ett effektivt och miljövänligt sätt kan rena avloppsvatten från näringsämnen utan att kostnaderna för reningen blir för stora. Biologisk fosforavskiljning (bio-P) utnyttjar mikroorganismer som naturligt kan ackumulera fosfor i sina celler. En kritisk faktor för en väl fungerande biologisk fosforavskiljning är tillgången till kolkälla i form av flyktiga fettsyror (VFA). Kommunalt avloppsvatten innehåller vanligen för lite VFA för att tillgodose bio-P-processens behov. Den totala tillgången på organiskt material i avloppsvattnet är dock ofta stor och möjligheten finns därmed att genom biologisk slamhydrolys internt producera VFA. Vid biologisk hydrolys av slam utnyttjas mikroorganismers naturliga förmåga att under anaeroba förhållanden bryta ned organiskt material till mer lättomsättliga föreningar. Duvbackens avloppsreningsverk i Gävle tillämpar biologisk fosforavskiljning och producerar VFA till bio-P-processen genom primärslamshydrolys och sidoströmshydrolys av returslam. I detta examensarbete har hydrolysprocesserna vid reningsverket utvärderats med avseende på processernas förmåga att producera VFA till det biologiska reningssteget. Utvärderingen gjordes genom att mäta förändringen i halten organiskt material över hydrolysbassängerna samt genom att bedöma effektiviteten i bio-P-processen i fullskala och vid labskaleförsök. Möjligheten att stänga av primärslamshydrolysen vid verket undersöktes. Ett försök till att optimera driften av sidoströmshydrolysen gjordes genom att utföra hydrolysförsök i laboratorieskala. Resultaten indikerade att produktionen av VFA i primärslamshydrolysen var begränsad och att processen därmed bör kunna stängas av. Innan detta görs bör dock kompletterande mätningar av halten löst COD över primärslamshydrolysen utföras. Vid samtliga mättillfällen uppmättes en betydande ökning i halten organiskt material över sidoströmshydrolysen. Baserat på detta och den i examensarbetet konstaterade effektiviteten i bio-P-processen drogs slutsatsen att sidoströmshydrolysprocessen vid Duvbackens reningsverk var välfungerande. Hydrolysförsöken pekade på att ett större utbyte av VFA skulle erhållas om en kortare uppehållstid än den nuvarande användes i sidoströmshydrolysen. Detta bör vidare undersökas genom fullskaleförsök vid verket.
The strong regulations concerning phosphorus removal from wastewater in Sweden has resulted in chemical precipitation being the most common treatment method for phosphorus at Swedish wastewater treatment plants (WWTP). Precipitation chemicals are expensive and have a negative environmental impact when produced and transported. More stringent wastewater treatment requirements have increased the need of new, eco-friendly treatment methods that effectively can remove nutrients from wastewater without being too expensive. Enhanced biological phosphorus removal (EBPR) utilizes microorganisms that have the natural capability of accumulating phosphorus in their cells. A critical factor for a well-functioning EBPR-process is the availability of carbon source in form of volatile fatty acids (VFA). Municipal wastewater normally contains too small amounts of VFA to satisfy the need of the EBPR-process. The total amount of organic matter in the wastewater is on the other hand large and the possibility consequently exists to internally produce VFA through sludge hydrolysis. Biological sludge hydrolysis takes advantage of the natural capability of microorganisms to degrade complex organic compounds into easily degradable organics. Duvbacken WWTP in Gävle uses EBRP for phosphorus removal and produces carbon source through hydrolysis of primary sludge and sidestream hydrolysis of return sludge. In this master thesis the hydrolysis processes at the WWTP was evaluated with regard to the capacity of the processes to produce VFA to the biological treatment step. The evaluation was performed by measuring the change in organic material content over the hydrolysis basins and by estimating the effectiveness of the EBPR-process in full scale and by laboratory experiments. The possibility to turn off the primary sludge hydrolysis process was examined. An attempt to optimize the operation of the sidestream hydrolysis process was made by conducting hydrolysis experiments in laboratory scale. The results indicated that the production of VFA by primary sludge hydrolysis was limited and that it thus would be possible to turn off the process. Before this is done complementary measurements of COD levels over the primary hydrolysis basin should be performed. At all times considerable increments in COD content was measured over the sidestream hydrolysis basin. Based on this and the in the thesis confirmed effectiveness of the EBRP-process the conclusion was drawn that the sidestream hydrolysis of return sludge at Duvbacken WWTP was well functioning. The hydrolysis experiments indicated that a larger VFA yield would be obtained if a shorter retention time than the present was used in the sidestream hydrolysis process. This should further be investigated by experiments in full scale at the WWTP.

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11

Hong, Yanjuan. "Enhanced Biological Phosphorus Removal for Liquid Dairy Manure." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/46067.

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Enhanced biological phosphorus removal (EBPR) has been widely used in municipal wastewater treatment, but no previous studies have examined the application of EBPR to treat dairy manure. This study was conducted to evaluate the (i) performance of pilot-scale EBPR systems treating liquid dairy manure, to balance the ratio of nitrogen to phosphorus in manure to meet crop nutrient requirements, (ii) effects of dissolved oxygen and solids retention time on the efficiency of EBPR, and (iii) effectiveness of gravity thickening for reducing the volume of harvested EBPR aerated mixed liquor. Two pilot-scale EBPR systems were used in this study. The ratio of the manure chemical oxygen demand expressed as volatile fatty acids to phosphorus used ranged from 18:1 to 45:1. The phosphorus removal efficiencies of the EBPR system were investigated at three solids retention times (4, 6 and 10 d), and three dissolved oxygen levels (3, 4 and 6 mg O2/L). The total phosphorus removal was highest (84%) at 10 d solids retention time and lowest (63%) at 4 d solids retention time. The sludge from the 6 d solids retention time tests had better sludge settling characteristics with a sludge volume index of 62 mL/g compared to 80 mL/g for the 4 d solids retention time. The EBPR system achieved 90% dissolved reactive phosphorus removal when the system was operated at 4 mg O2/L, and the ratio of nitrogen to phosphorus in effluent increased to about 5:1, which was higher than the normal ratio in dairy manure. On the other hand, phosphorus removal performance deteriorated when dissolved oxygen level was 3 mg O2/L. In the gravity thickening tests, 93-95 % total suspended solids (TSS) was removed from the settled supernatant, with 1.2 to 1.54 % total solids (TS) in the settled solids after 90 min gravity-induced thickening. The extent of phosphorus release during gravity thickening process needs to be further investigated.
Master of Science

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12

Yue, Chaoyang. "Phosphorus recovery from a membrane enhanced biological phosphorus removal (MEBPR) process." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/60775.

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Phosphorus is an essential yet limited element for sustaining life of human beings. Municipal wastewater contains rich phosphorus, which is not sufficiently recovered or recycled. This dissertation developed a system that could recover phosphorus from wastewater as struvite fertilizer (MgNH₄PO₄•6H₂O). Such a system included three major components — a membrane enhanced biological phosphorus removal (MEBPR) process, a side-stream unit to extract PO₄³⁻ and NH₄⁺ from wasted solids, and a struvite crystallizer. This dissertation focused on optimizing the first two steps through pilot- and bench-scale studies, respectively. The MEBPR process was tested at increasing solids retention time (SRT) to increase total phosphorus (TP) concentration in mixed liquor (ML). The operation at SRT = 60 days proved to be technically feasible and achieved comparable phosphorus removal (95−96 %) and organic carbon removal (91−92 %) to that observed during operation at the control SRT (25 days). The 60-day SRT operation also removed 14 % more nitrogen, wasted 17 % less dry solids, more than doubled the TP concentration of aerobic zone ML, but did not increase membrane fouling rates. Cost analyses showed that the energy requirements were 0.94 and 2.1 kWh/m³ of permeate for SRT = 25 and 60 days, both within the reported range for full-scale membrane bioreactors. To solve foaming problem in the MEBPR process, foam was characterized as an alternative resource for phosphorus recovery. Methods were assessed to extract phosphorus from ML and foam. With suitable conditions, microwave-based hydrogen peroxide advanced oxidation process (MW-H₂O₂ AOP) could extract > 90 % of TP as PO₄-P from foam, and anaerobic P-release could extract up to 60 % from ML. Anaerobic digestion could extract 44−46 % of TP under digestion pHs, 64−65 % with pH ≤ 5.5, and generate sufficient NH₄⁺ that matched the quantities of PO₄³⁻ extracted. Finally, a system was proposed that included an MEBRP process operating at SRT = 60 days, and an anaerobic digester to extract both PO₄³⁻ and NH₄⁺. This system could recover about 60 % of the incoming phosphorus in the influent. To recover more phosphorus, MW-H₂O₂ AOP could be used after anaerobic digestion, whenever justified.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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13

Crocetti, Gregory Robert. "The molecular microbial ecology of enhanced biological phosphorus removal /." St. Lucia, Qld, 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16512.pdf.

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14

Simm, Robert. "Enhanced biological phosphorus removal using a sequencing batch RBC." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28517.

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The objective of the research program was to demonstrate the technical feasibility of removing phosphorus, by the enhanced biological phosphorus removal mechanism, from domestic wastewater using a laboratory scale Sequencing Batch Rotating Biological Contactor (SBRBC). The rotating discs of the RBC were subjected to alternating anaerobic/aerobic conditions by varying the water level in the reaction vessel. At the start of the treatment cycle, the RBC reactor would be filled submerging the rotating discs and ensuring anaerobic conditions in the RBC biofilm. Acetate would be added to the reaction vessel at this time. Following the batch anaerobic react period part of the reactor contents were decanted to either the sewage feed tank or a separate holding vessel to later become part of the influent for the next treatment cycle. With the rotating: discs of the-RBC partially submerged oxygen was available to the bacteria, in the RBC biofilm. Three operating schedules were tried with the above process. Each operating schedule differed in the way the decanted wastewater from the anaerobic phase was handled. Batch tests were conducted weekly to determine the nature of the biological reactions taking place in each of the batch anaerobic and aerobic phases. The SBRBC process showed promise for enhanced biological phosphorus removal from domestic wastewater. Carbon removal and nitrification of the wastewater were secondary benefits to this process. The success of the process was found to be dependent on the attainment of proper anaerobic conditions at the start of each treatment cycle.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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15

Hansson, Josefin. "Järns påverkan på biologisk fosforrening : en studie av reningen vid block B vid Kungsängsverket, Uppsala." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-297202.

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Grundämnet fosfor är essentiellt för alla levande organismer men kan i överskott leda till problem med övergödning. Det finns därför höga krav på halten avloppsreningsverk släpper ut till recipienter. Idag sker stora delar av fosforreningen kemiskt genom dosering av fällningskemikalier. Det finns dock fördelar med att istället använda en biologisk metod som bygger på att reningsförhållandena premierar tillväxt av bakterier med möjlighet att ta upp mer fosfor än de behöver för sin cellväxt. Bakterierna gynnas genom omväxlande anaeroba och aeroba zoner samt en god tillgång på lättillgänglig kolkälla och fosfor. Många reningsverk kombinerar den kemiska och biologiska fosforreningen men de är inte alltid kompatibla och den kemiska kan störa ut den biologiska. På Kungsängsverket finns sedan 2010 förutsättningar för en biologisk fosforreduktion men processen har inte fungerat tillfredsställande. Anledningen tros vara höga halter järn i slammet. Järnet fäller delar av den fosfor som är nödvändig för processen. Arbetet har därför syftat till att undersöka om det går att tvätta bioslammet på järn och på så sätt nå en fungerande fosforrening; vid vilka järnhalter detta sker och vilka besparingar det skulle kunna leda till för Uppsala Vatten och Avfall AB. För vidare utredning genomfördes ett pilotförsök där två reaktorer byggdes, en referensreaktor och en försöksreaktor. Reaktorerna matades sedan med vatten med olika sammansättning, främst gällande järnhalt. Även befintlig data för verket och uppgifter kring förutsättningarna på andra reningsverk med en fungerande biologisk fosforreduktion undersöktes. Pilotförsöket visade att det går att tvätta bioslammet på järn då en sjunkande halt sågs under försökets gång. Halten sjönk från 40 mg Fe/g TS till 18 mg Fe/g TS i försöksreaktorn. En fungerande fosforrening uppnåddes aldrig så inga slutsatser gällande besparingar, eller vid vilka järnhalter en fungerande rening sker, kan dras. Andra reningsverk med biologisk fosforrening har kring 10 mg Fe/g TS vilket ger en indikation på vad halten bör vara. Pilotförsöket visade också att dosering av polymer ledde till att stora delar av den inkommande kolkällan fälldes, kolkälla som behövs för fungerande fosfor- och kväverening. Recirkulation av nitratkväve sågs hämma det fosforsläpp som vid fungerande rening ska ske i den anaeroba zonen och tros ha stört reningen under försökets gång. Förutsättningarna för biologisk fosforrening på Kungsängsvrket anses inte vara optimala gällande avloppsvattnets sammansättning, recirkulering av nitratkväve till den anaeroba zonen och mängden lättillgänglig kolkälla från hydrolysbassängen.
Phosphorus is an essential element but can cause eutrophication when present in high concentrations. Emission requirements from municipal wastewater treatment plants are therefore strict. Today chemical precipitation is common but there are advantages to using a biological method. It is based on creating conditions that favor growth of a special type of bacteria. These bacteria absorb more phosphorus than they need for growth. To do this they need alternating anaerobic and aerobic zones and access to carbon and phosphorus. A combination between the two methods are common but the precipitation chemicals can under some conditions disturb the biological removal. At Kungsängsverket the process of biological phosphorus removal has been in place since 2010. It has not worked adequately and the reason could be high concentrations of iron in the biological sludge. The purpose of this thesis has therefore been to investigate whether it is possible to wash out the iron from the bio-sludge and as a result reach a satisfying reduction of phosphorus, to see at which iron content this might happen and what kind of savings a functioning biological phosphorus removal might lead to for Uppsala Vatten och Avfall AB. To test the hypothesis two reactors were built, a reference reactor and an experimental reactor. The two were fed with water with different compositions, primarily regarding iron content. Also, existing data was examined from the plant and records regarding sludge composition at plants with working biological phosphorus removal. The pilot test showed that it was possible to wash out the iron from the biological sludge. Iron content in the experimental reactor went down from 40 mg Fe/g DM to 18 mg Fe/g DM. A satisfying reduction of phosphorus was never achieved and no conclusions can be drawn regarding savings or at which iron content a reduction might happen. Other wastewater treatment plants with biological phosphorus reduction have shown to have a content of about 10 mg Fe/g DM which can be used as an indication. According to the pilot test dosing of polymer can lead to a large precipitation of carbon source. Lack of carbon will inhibit phosphorus and nitrogen removal. Circulation of nitrate repressed the release of phosphate in the anaerobic zone and is believed to have disturbed the removal during the pilot. The conditions for biological phosphorus removal at Kungsängsverket are not ideal as to the composition of the wastewater, the circulation of nitrate to the anaerobic zone and the amount of carbon source from the hydrolysis.

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16

Sriwiriyarat, Tongchai. "Mathematical Modeling and Evaluation of Ifas Wastewater Treatment Processes for Biological Nitrogen and Phosphorus Removal." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/28733.

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The hybrid activated sludge-biofilm system called Integrated Fixed Film Activated Sludge (IFAS) has recently become popular for enhanced nitrification and denitrification in aerobic zones because it is an alternative to increasing the volume of treatment plant units to accomplish year round nitrification and nitrogen removal. Biomass is retained on the fixed-film media and remains in the aerobic reactor, thus increasing the effective mean cell resident time (MCRT) of the biomass and providing the temperature sensitive, slow growing nitrifiers a means of staying in the system when they otherwise would washout. While the utilization of media in aerobic zones to enhance nitrification and denitrification has been the subject of several studies and full-scale experiments, the effects and performances of fixed film media integrated into the anoxic zones of biological nutrient removal (BNR) systems have not adequately been evaluated as well as the impacts of integrated media upon enhanced biological phosphorus removal (EBPR). Also, user-friendly software designed specifically to simulate the complex mixture of biological processes that occur in IFAS systems are not available. The purpose of this research was to more fully investigate the effects of integrated fixed film media on EBPR, to evaluate the impacts of media integrated into the anoxic zone on system performance, and to develop a software program that could be used to simulate the effects of integrating the various types of media into suspended growth biological nutrient removal (BNR) systems. The UCT type configuration was chosen for the BNR system, and Accuweb rope-like media was selected for integration into the anoxic zones of two IFAS systems. The media also was integrated into the aerobic reactors of one of the systems for comparison and for further investigation of the performance of the Accuweb media on enhanced nitrification and denitrification in the aerobic zones. The experiments were conducted at 10 day total MCRT during the initial phase, and then at 6 days MCRT for the experimental temperature of 10 oC. A13 hour hydraulic retention time (HRT) was used throughout the study. A high and a low COD/TP ratio were used during the investigation to further study the effects of integrated media on EBPR. The PC Windows based IFAS program began with the concepts of IAWQ model No. 2 and a zero-dimensional biofilm model was developed and added to predict the IFAS processes. Experimental data from the initial study and existing data from similar studies performed at high temperatures (>10oC) indicated that there were no significant differences in BNR performances between IFAS systems with media integrated into the anoxic and aerobic or only aerobic zones and a suspended growth control system maintained at the same relative high MCRT and temperature values. Even though greater biological nitrogen removal could not be achieved for the experimental conditions used, the experimental results indicated that the IFAS systems with fixed film media installed in the anoxic zone have a greater potential for denitrification than conventional BNR systems. As much as 30 percent of the total denitrification was observed to occur in the aerobic zones of the system installed the media only anoxic zones and 37% in the system with integrated media in both anoxic and aerobic zones where as no denitrification was observed in the aerobic zones of the control system when the systems were operated at 6 days MCRT and COD/TP of 52. It is statistically confirmed EBPR can be maintained in IFAS systems as well as Control systems, but the IFAS processes tend to have more phosphorus release in the anoxic zones with integrated fixed film installed. Further, the combination of split flow to the anoxic zone and fixed film media in the anoxic zone resulted in the decreased EBPR performances in the IFAS system relative to the control system.
Ph. D.

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17

Wilmes, Paul. "Metaproteomic investigations of enhanced biological phosphorus removal in activated sludge." Thesis, University of East Anglia, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426993.

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18

Pattarkine, Vikram Madhao. "The role of metals in enhanced biological phosphorus removal from wastewater." Diss., This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08082007-120247/.

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19

Geng, Zuohong. "Study of membrane fouling in a membrane enhanced biological phosphorus removal process." Thesis, University of British Columbia, 2006. http://hdl.handle.net/2429/30872.

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Membrane fouling is an inherent problem that has been associated with membrane processes since the emergence of membrane technologies. In the present research, membrane fouling in a membrane enhanced biological phosphorus removal (MEBPR) process was, for the first time, investigated systematically with respect to membrane fouling mechanisms, roles of sludge constituents in membrane filtration, characteristics of membrane foulants, and the relation of sludge properties to fouling. It was revealed that membrane fouling in the pilot scale MEBPR process was hydraulically irreversible and was mainly due to the adsorption of dissolved organic matter in activated sludge mixed liquor, particularly extracellular polymeric substances (EPS) such as carbohydrates and humic or humic-like substances. Large sludge floes were found to likely exert dual effects on membrane filtration. At low flux, they tended to induce hydraulic resistance via sludge deposition. At high flux, large sludge floes seemed to be able to mitigate fouling by sterically hindering the transport of soluble and colloidal sludge components to membrane surfaces. Unlike in other wastewater treatment membrane bioreactors, biofouling in the form of microbial growth was not significant in the studied MEBPR process due to the vigorous aeration and frequent backflushing applied. Inorganic fouling (i.e. precipitation of struvite) was also not observed. The accumulation of foulants (i.e. carbohydrates and humic or humic-like substances) on membrane surfaces resulted in an increase of surface hydrophobicity, which in turn might have accelerated the fouling process. The physical and biochemical properties of sludge, including floe size distribution, zeta potential, relative hydrophobicity, bound and unbound (soluble) EPS content, were also examined in the present research. Compared to a conventional sludge, the higher content of soluble EPS in activated sludge mixed liquor and the smaller floe size distribution were very likely responsible for the higher fouling propensity of the MEBPR sludge. Thus, the content of soluble EPS in mixed liquor was suggested to be a key property to evaluate the fouling potential of activated sludge mixed liquor. Contrary to the literature, the content of EPS bound in the sludge matrix was found not to be a direct influencing factor to membrane fouling.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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20

Bahadoorsingh, Parmeshwaree. "Comparison of nitrification activity in membrane and conventional enhanced biological phosphorus removal processes." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/29539.

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While research is conclusive that the membrane bioreactor process performance in removing the carbonaceous and phosphorus constituents of wastewater is superior or equivalent to a conventional gravity separation process, there have been conflicting reports regarding its ability to achieve nitrification rates comparable to the conventional process. In this long-term study conducted at University of British Columbia’s (UBC’s) wastewater treatment pilot plant facility, the specific nitrification activity of a membrane enhanced biological phosphorus removal (EBPR) process was compared to that of a conventional EBPR process operating under identical conditions to identify factors that influence the relative nitrification rate of the processes. The specific nitrification rate measured from batch experiments showed a natural variation between the processes. There were periods where the specific nitrification rate of the membrane process was either consistently high or consistently low, relative to the conventional process. Average rates were nearly equal, however, the membrane process showed less variability in the individual rates. Nitrifier decay rates measured during the various performance periods conformed to the variation observed as rates for the membrane process were lower relative to the conventional process during periods where the specific nitrification rate for the membrane process was higher and vice versa. The presence of rotifers caused an increase in the decay rate of the conventional process. These organisms were absent in the membrane process. Vigorous coarse bubble aeration did not affect the decay rate. Terminal restriction fragment length polymorphisms (T-RFLP) analysis showed that ammonia-oxidizing (AOB) communities differed for the two processes, however the nitrite-oxidizing bacteria (NOB) communities as represented by the genus Nitrobacter and Nitrospira were similar for both processes. Temperature effects were significant for both AOB and NOB communities, but the effect was greater for the AOB community. Community shifts for the AOB were observed to occur during plant operation. Quantification of the nitrifiers by a real time polymerase chain reaction assay indicated similar quantities of AOB, Nitrobacter and Nitrospira in the two processes with Nitrospira being the most abundant of the nitrifiers present in the systems. AOB and Nitrobacter quantities correlated with the relative nitrification rate of the processes.

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21

Yanosek, Kristina Anne. "Enhanced Biological Phosphorus Removal from Dairy Manure to Meet Nitrogen:Phosphorus Crop Nutrient Requirements." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/35782.

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Over the last two decades, livestock operations have become highly concentrated due to growing trends towards larger, more confined facilities and a decrease in cropland on smaller farms. This has led to greater amounts of excess manure nutrients on farms, increasing the potential for nutrient pollution of water bodies from runoff. The purpose of this study was to determine if enhanced biological phosphorus removal (EBPR) is a viable alternative for managing excess manure nutrients on dairy farms. Assessment of EBPR involved the investigation of various aspects of wastewater treatment modeling and design and farm nutrient management. The fermentation potential (volatile fatty acid (VFA) production) of dairy manure was determined through laboratory analysis to be 15.3% of the total COD. Total VFA production was composed of 57, 23, and 20% acetic, propionic, and butyric acids, respectively. The EBPR component of the BioWin wastewater treatment model was evaluated through a sensitivity analysis. The parameters to which effluent phosphate (PO4) concentration was most sensitive were maximum specific growth rate, growth yield, aerobic PO4 uptake rate per unit poly-b-hydroxybutyrate (PHB) utilized, PHB yield from VFA, PO4 release per unit VFA uptake, and fraction of releasable PO4. An EBPR sequencing batch reactor (SBR) was designed for a dairy farm with 700 lactating cows and 325 ha of corn silage. An economic analysis of EBPR for dairy farms employing P-based manure applications was completed. The cost of hauling excess manure to nutrient deficient farms was the most significant expense in comparing costs of manure management with and without EBPR. For a herd of 700 lactating cows, utilizing EBPR was more economical for farms with 270 ha or less cropland, while EBPR did not offer an economic advantage for farms over 270 ha.
Master of Science

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22

Al-Atar, Eman. "Dynamic modeling and process design of a membrane enhanced biological phosphorus removal process." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31205.

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The design and operation of the membrane enhanced biological phosphorus removal (MEBPR) process was studied in the current research to utilize the utmost capacity of the membrane system for operating the process under high influent loads. The study was conducted in two parts. In the first part, a dynamic model was calibrated to predict data collected from the UBC MEBPR pilot plant. Then the calibrated model was utilized in simulation studies to develop guidelines for the design and operation of a UCT-type MEBPR process under high flowrates without jeopardizing the effluent quality. The Technical University of Delft model combined with ASM2d model (TUDP) which is developed for conventional biological phosphorus systems was found sufficient to describe the process behavior of the MEBPR process. The trend of the measured concentration profiles were reasonably predicted, but the exact concentration values for the anoxic nitrate and the effluent ortho-phosphate were not predicted. The calibrated model for the MEBPR process was able to predict the measured data collected from the UBC conventional enhanced biological phosphorus removal (CEBPR) process without changing any of the model parameters except for the rate of polyphosphate formation, k[sub pp], which was increased from 0.1 to 0.2 g P/(g COD • d) to better predict the anoxic ortho-phosphate concentrations. Simulation studies for the UCT-type MEBPR process showed that the sludge mass distribution in the bioreactor zones of the anaerobic and the aerobic zone are critical for the bio-P removal and the nitrification processes respectively. Appropriate design of the bioreactor zone volumes is important to ensure proper sludge mass distribution in the biological zones. A constant influent volatile fatty acid to total phosphorus concentration was also found important for an efficient bio-P removal process. The aerobic recycle flow was found to be most important for reducing the effluent nitrate concentration while minimizing nitrate leakage to the anaerobic zone. Based on the experimental results and the simulation studies carried out in the current project, a set of guidelines for the design and operation of a UCT-type MEBPR process and the application of process control were developed to achieve stable process performance for nutrient removal under high flowrate operation.
Applied Science, Faculty of
Chemical and Biological Engineering, Department of
Graduate

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23

Srinivas, Hemanth Kumar. "Coupling of phosphorus recovery to an enhanced biological phosphorus removal process through a sidestream : a pilot scale study." Thesis, University of British Columbia, 2006. http://hdl.handle.net/2429/32403.

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This research was initiated with the purpose to remove and recover phosphorus simultaneously, by coupling a sidestream for phosphorus recovery to an enhanced biological phosphorus removal (EBPR) process. Sidestream process comprised of a phosphorus release unit along with a clarifier connected to the MAP (magnesium ammonium phosphate) crystallizer. To understand the sidestream process and to investigate the optimum operating conditions, the configuration was simulated using ASM2-Delft metabolic bio-P model on AQUASIM platform. The simulation exercise revealed that anoxic is the best zone to take sidestream when taken individually and anoxic/anaerobic when taken in combination. In both the cases N: P molar ratio of the supernatant was more than 1:1 which is essential for the recovery of phosphorus as struvite. The minimum hydraulic retention time required in the phosphate release unit was found to be around one to two hours, above which there was no considerable amount of phosphate released. Potentially, up to 78% of the incoming phosphorus is estimated to be recovered by implementing sidestream technology. Based on the simulation results, sidestream process was successfully implemented at UBC pilot plant for both membrane and conventional enhanced biological phosphorous removal processes (MEBPR and CEBPR). The MAP crystallizer was used to recover phosphorus as struvite. Although, the recovery efficiency obtained was not very high (approximately 60%), the refined conditions as suggested should yield better results. Sidestream wasting method to control the solid retention time of the process indicated selective increase of phosphorus accumulating organisms in the main EBPR process. Sidestream wasting also reduced the phosphorus rich sludge wasting from the aerobic zone of the EBPR process. Magnesium (Mg) was added to the influent of the process to increase the Mg²⁺ concentration in the sidestream supernatant to provide better conditions for struvite formation. The CEBPR and MEBPR processes experienced poor phosphorus removal after Mg addition was started. More detailed investigation is suggested to look in to the effects of magnesium on the EBPR process along with potassium.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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24

Lanham, Ana Alexandra Barbosa. "Full-scale biological phosphorus removal: quantification of storage polymers, microbial performance and metabolic modelling." Doctoral thesis, Faculdade de Ciências e Tecnologia, 2012. http://hdl.handle.net/10362/8052.

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Dissertação para obtenção do Grau de Doutor em Engenharia Química e Bioquímica
Enhanced biological phosphorus removal (EBPR) can be applied in wastewater treatment plants (WWTPs), as a sustainable and efficient way to remove phosphorus from wastewater and hence reduce its impact on eutrophication. This work characterises the performance, metabolism and identity of the microbial EBPR communities in full-scale WWTPs. The accurate quantification of the internal storage compounds, namely polyhydroxyalkanoate (PHA) and glycogen, is crucial to the characterisation of EBPR. The optimal glycogen and PHA quantification methods were sensitive to the heterogeneity of the sample, in terms of its microbial structure (floccular or granular) and, for PHA, in terms of the size and the number of substituents of the monomers forming the copolymer. Additionally, by characterising six full-scale EBPR WWTPs, in terms of their overall performance, microbial identity and metabolism, the composition of polyphosphate accumulating organisms (PAOs) was fairly similar in all plants. Also, a warmer climate was not sufficient to justify a higher presence of glycogen accumulating organisms (GAOs). Differing levels of denitrifying PAOs were obtained in different plants and the involvement of the tricarboxylic acid (TCA) cycle in the anaerobic metabolism of PAOs was observed. Furthermore, a metabolic model developed in this study, which incorporates the involvement of the anaerobic TCA cycle and a new description of the aerobic maintenance processes, was able to accurately describe the chemical cycling of soluble and intracellular compounds, while requiring a simple calibration procedure. A series of simulations demonstrated that lower acetate concentrations in the feed and higher aeration retention times would favour the TCA cycle metabolism over the glycolysis pathway, which would explain why the former has been more frequently encountered in WWTPs and the latter in lab-scale enriched cultures.
Fundação para a Ciência e Tecnologia - PhD grant (SFRH/BD/29477/2006)

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25

Wang, Niandong. "Experimental study and mathematical modeling of enhanced biological phosphorus removal using glucose as the dominant substrate." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ63936.pdf.

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26

Lawson, Christopher Evan. "Population dynamics and metabolic potential of a pilot-scale microbial community performing enhanced biological phosphorus removal." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/50362.

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Enhanced biological phosphorus removal (EBPR) is an environmental biotechnology of global importance, essential for protecting receiving waters from eutrophication and enabling phosphorus recovery. Current understanding of EBPR is largely based on empirical evidence and black-box models that fail to appreciate the driving force responsible for nutrient cycling and ultimate phosphorus removal, namely microbial communities. Accordingly, this thesis focused on understanding the microbial ecology of a pilot-scale microbial community performing EBPR to better link bioreactor processes to underlying microbial agents. Initially, temporal changes in microbial community structure and activity were monitored in a pilot-scale EBPR treatment plant by examining the ratio of small subunit ribosomal RNA (SSU rRNA) to SSU rRNA gene over a 120-day study period. Although the majority of operational taxonomic units (OTUs) in the EBPR ecosystem were rare, many maintained high potential activities, suggesting that rare OTUs made significant contributions to protein synthesis potential. Few significant differences in OTU abundance and activity were observed between bioreactor redox zones, although differences in temporal activity were observed among phylogenetically cohesive OTUs. Moreover, observed temporal activity patterns could not be explained by measured process parameters, suggesting that alternate ecological forces shaped community interactions in the bioreactor milieu. Subsequently, a metagenome was generated from pilot plant biomass samples using 454 pyrosequencing. Comparison of microbial community metabolism across multiple metagenomes from different environments revealed that EBPR community function was enriched in biofilm formation, phosphorus metabolism, and aromatic compound degradation, reflective of local bioreactor conditions. Population genomes binned from metagenomic contigs showed that M. parvicella genomes displayed remarkable genomic cohesion across EBPR ecosystems, where functional differences related to biofilm formation and antibiotic resistance, likely reflecting adaptation to habitat-specific selection pressures. Additionally, novel metabolic insights into Gordonia spp. in the EBPR ecosystem suggested a potential role for its involvement in polyphosphate and triacylglycerol cycling. Overall, these findings offer valuable insight on EBPR microbial ecology and will guide future studies aimed at monitoring spatiotemporal patterns in population dyanmics and gene expression. Moreover, this work demonstrates that molecular sequencing approaches can be successfully used to gain deeper insight on microbial communities responsible for wastewater remediation.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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Abdullah, Syed. "Investigation of effect of dynamic operational conditions on membrane fouling in a membrane enhanced biological phosphorus removal process." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/264.

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The membrane bioreactor (MBR) is becoming increasingly popular for wastewater treatment, mainly due to its capability of producing high quality effluent with a relatively small footprint. However, high plant maintenance and operating costs due to membrane fouling limit the wide spread application of MBRs. Membrane fouling generally depends on the interactions between the membrane and, the activated sludge mixed liquor, which in turn, are affected by the chosen operating conditions. The present research study aimed to explore the process performance and membrane fouling in the membrane enhanced biological phosphorus removal (MEBPR) process under different operating conditions by, (1) comparing two MEBPRs operated in parallel, one with constant inflow and another with a variable inflow, and by, (2) operating the MEBPRs with different solids retention times (SRT). On-line filtration experiments were conducted simultaneously in both MEBPR systems by using test membrane modules. From the transmembrane pressure (TMP) data of the test membrane modules, it was revealed that fouling propensities of the MEBPR mixed liquors were similar in both parallel reactors under the operating conditions applied, although the fouling propensity of the aerobic mixed liquors of both reactors increased when the SRT of the reactors was reduced. Routinely monitored reactor performance data suggest that an MEBPR process with a varying inflow (dynamic operating condition) performs similarly to an MEBPR process with steady operating conditions at SRTs of 10 days and 20 days. Mixed liquor characterization tests were conducted, including critical flux, capillary suction time (CST), time to filter (TTF) and, bound and soluble extracellular polymeric substances (EPS) were quantified, to evaluate their role on membrane fouling. The tests results suggest that the inflow variation in an MEBPR process did not make a significant difference in any of the measured parameters. With decreased SRT, an increase in the concentrations of EPS was observed, especially the bound protein, and the bound and soluble humic-like substances. This suggests that these components of activated sludge mixed liquors may be related to membrane fouling. No clear relationship was observed between membrane fouling and other measured parameters, including critical flux, normalized CST and normalized TTF.

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Abdullah, Syed Zaki. "Investigation of effect of dynamic operational conditions on membrane fouling in a membrane enhanced biological phosphorus removal process." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/264.

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The membrane bioreactor (MBR) is becoming increasingly popular for wastewater treatment, mainly due to its capability of producing high quality effluent with a relatively small footprint. However, high plant maintenance and operating costs due to membrane fouling limit the wide spread application of MBRs. Membrane fouling generally depends on the interactions between the membrane and, the activated sludge mixed liquor, which in turn, are affected by the chosen operating conditions. The present research study aimed to explore the process performance and membrane fouling in the membrane enhanced biological phosphorus removal (MEBPR) process under different operating conditions by, (1) comparing two MEBPRs operated in parallel, one with constant inflow and another with a variable inflow, and by, (2) operating the MEBPRs with different solids retention times (SRT). On-line filtration experiments were conducted simultaneously in both MEBPR systems by using test membrane modules. From the transmembrane pressure (TMP) data of the test membrane modules, it was revealed that fouling propensities of the MEBPR mixed liquors were similar in both parallel reactors under the operating conditions applied, although the fouling propensity of the aerobic mixed liquors of both reactors increased when the SRT of the reactors was reduced. Routinely monitored reactor performance data suggest that an MEBPR process with a varying inflow (dynamic operating condition) performs similarly to an MEBPR process with steady operating conditions at SRTs of 10 days and 20 days. Mixed liquor characterization tests were conducted, including critical flux, capillary suction time (CST), time to filter (TTF) and, bound and soluble extracellular polymeric substances (EPS) were quantified, to evaluate their role on membrane fouling. The tests results suggest that the inflow variation in an MEBPR process did not make a significant difference in any of the measured parameters. With decreased SRT, an increase in the concentrations of EPS was observed, especially the bound protein, and the bound and soluble humic-like substances. This suggests that these components of activated sludge mixed liquors may be related to membrane fouling. No clear relationship was observed between membrane fouling and other measured parameters, including critical flux, normalized CST and normalized TTF.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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29

Khouri, Tarek Zaki. "The effects of glucose and fatty acids on enhanced biological phosphorus removal using a sequencing batch reactor." Master's thesis, University of Central Florida, 1996. http://digital.library.ucf.edu/cdm/ref/collection/RTD/id/16679.

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University of Central Florida College of Engineering Thesis
Two anaerobic/aerobic sequencing batch reactors (SBRs) were used to evaluate enhanced biological phosphorus removal (EBPR). The first SBR, designated the Glucose SBR, was run for a period of four months. It received a synthetic wastewater plus glucose as a supplemental carbon source. The second SBR, the Isovaleric SBR, was run for three months. During the first month, isovaleric acid was its supplemental carbon source while for the remaining time period, no supplemental carbon source was added to the feed. Steady-state data from the SBR receiving isovalerate yielded the highest phosphorus (P) removals observed during the study, with a mixed liquor volatile suspended solid (MLVSS) P content of 7.2%. The next highest removals were observed when prefermented glucose was received, which yielded a MLVSS P content of 6.4%. The lowest removals were observed when no supplemental carbon source was added to the SBR influent, with at 4.4% MLVSS P content. Batch experiments were also conducted to quantify the effect of EBPR of glucose and the volatile fatty acids (VFAs) acetic acid, propionic acid, valeric acid, and isovaleric acid. Compounds giving the largest anaerobic P release ultimately yielded the lowest effluent P concentrations. At 0.80 mmoles/l, isovaleric acid resulted in anaerobic P released 9.5 mg/l greater than an equal amount of glucose or propionic acid, but ultimately gave effluent P values roughly 4 mg/l lower than either. Ratios of aerobic P uptake/anaerobic P release were found to be roughly equal for all the VFAs when the VFAs were compared on a molar basis. Propionic acid had aerobic P uptake/anaerobic P release ratios similar to the other VFAs. It also behaved the same as all the other VFAs with respect to the effect of concentrations added to the batch experiment; however, the magnitude of its removal was significantly lower than all the other substrates. Glucose, on the other hand, behaved differently from all the VFAs. Glucose aerobic P uptake/anaerobic P release ratios varied with concentration, which was not the case for the others substrates. Also, glucose P net removals decreased at concentrations higher than 0.60 mmoles/l. Glucose also resulted in net P removals roughly 2mg/l higher than propionic acid, but ultimately gave lower net P removal than isovaleric, valeric and acetic acids.
M.S.;
Civil and Environmental Engineering
Engineering;
Environmental Engineering Sciences
111 p.
xi, 111 leaves, bound : ill. ; 28 cm.

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30

Rey, Martínez Natalia. "Advances in enhanced biological phosphorus removal: amino acids as carbon source and envisaging its integration in high-rate systems." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/669366.

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Les estacions depuradores d’aigües residuals (EDARs) urbanes estan àmpliament implantades en els països industrialitzats i han d’incorporar processos que permetin l’eliminació biològica de nutrients (nitrogen (N) i fòsfor (P)). A escala laboratori, l’eliminació biològica de fòsfor està altament estudiada però, en la majoria dels casos, utilitzant substrats senzills (àcids grassos volàtils) com a font de carboni. Això dona lloc al desenvolupament d’una població microbiana en la qual predominen uns bacteris acumuladors de fòsfor (Polyphosphate Accumulating Organisms, PAO) catalogats com Accumulibacter. No obstant això, l’impuls de les noves tècniques d’identificació microbiològiques ha demostrat la presència d’altres PAO, diferents als Accumulibacter, a les estacions depuradores d’aigües residuals (EDARs). Per tant, ja que l’aigua residual real és una matriu complexa composta principalment per lípids, proteïnes i carbohidrats, neix la necessitat d’estudiar aquest procés biològic utilitzant substrats més complexos i a una major escala. En aquesta tesi es va proposar operar una planta pilot amb configuració A2/O per a l’eliminació biològica simultània de matèria orgànica, N i P usant glutamat com a font de carboni i nitrogen. A més a més, es va operar un reactor discontinu utilitzant caseïna hidrolitzada com a única font de carboni. Com a resultat, es va desenvolupar una comunitat microbiana enriquida en Thiothrix (37%) i Comamonadaceae (15.6%) en el cas del sistema A2/O, i unes llots enriquides en Tetrasphaera en el cas del SBR. Aquestes poblacions microbianes tenen trets diferenciadors dels cultius enriquits en Accumulibacter. Els tractaments convencionals de fangs actius presenten un gran consum energètic associat principalment a l’aeració i al tractament dels llots. A més a més, la matèria orgànica es mineralitza o es destina a la desnitrificació, en comptes de ser utilitzada per la producció de biogàs. Per tot això, les EDARs són instal·lacions consumidores d’energia. Així doncs, el repte existent avui dia és transformar les EDARs en instal·lacions autosuficients energèticament, mitjançant la implantació del procés A/B, que consta d’una primera etapa, etapa A, en la qual treballant a temps de residència cel·lular (TRC) i hidràulic (TRH) baixos, es pretén minimitzar la mineralització de la matèria orgànica i que aquesta s’adsorbeixi al fang per posteriorment destinar aquests llots a la producció de biogàs; i una etapa B per l’eliminació autotròfica del nitrogen. Malgrat això, aquest procés no contempla l’eliminació biològica de fòsfor. Per tant, aquesta tesi pretén investigar la possible integració de l’eliminació biològica de fòsfor en l’etapa A del procés A/B, mitjançant la incorporació d’una zona anaeròbia que permeti el creixement de PAO. No obstant això, s’ha d’estudiat que aquest bacteris es renten del sistema quan el TRC baixa dels 4 dies, per tant es fa necessari treballar a TRC majors dels típicament utilitzats en els sistemes d’alta càrrega (TRC<2 dies). Per una altra banda, l’influent real utilitzat en aquest estudi tenia un baix contingut en matèria orgànica, pel que ha estat necessari aportar-la externament per desenvolupar l’activitat PAO.
Urban wastewater treatment plants (WWTPs) are widely implemented in industrialized countries and they must incorporate processes for nutrients removal (nitrogen (N) and phosphorus (P)). Enhanced biological phosphorus removal (EBPR) has been highly studied at lab scale using simple substrates as carbon source, i.e. volatile fatty acids. As a result, a microbial population enriched in polyphosphate accumulating organisms (PAO) is developed, being Candidatus Accumulibacter phosphatis the species of PAO most frequently found. However, the new microbial identification technologies have demonstrated the presence of other PAO different than Accumulibacter in WWTPs. Since real wastewater is a complex matrix, mainly composed of lipids, proteins and carbohydrates, the need to study EBPR process using complex substrates has arisen. Furthermore, studies on a larger scale than lab-scale should be also performed. In this thesis, the operation of a pilot plant with A2/O configuration for simultaneous removal of organic matter, N and P using glutamate as carbon and nitrogen source was proposed. Moreover, a sequencing batch reactor (SBR) using casein hydrolysate as sole carbon source was operated. As a result, a microbial community enriched in Thiothrix (37%) and Comamonadaceae (15.6%) in the case of A2/O system and a biomass enriched in Tetrasphaera in the SBR were developed. These microbial communities present important differences in comparison to Accumulibacter-enriched systems. Conventional activated sludge process presents high energy consumption, mainly associated to aeration and sludge treatment. In addition, organic matter is mineralized or used for denitrification instead of being utilized for biogas production. For these reasons, WWTPs are energy consuming facilities. Nowadays, the transformation of conventional WWTPs into energy self-sufficient facilities is feasible by implementing the A/B process, which consist of a first step, A-stage, which aims at maximizing the carbon capture into the sludge for being treated through an anaerobic digestion system for biogas production; and a second step, B-stage, where the nitrogen is removed through an autotrophic process. However, this process does not include biological P removal. Therefore, this thesis aims to investigate the possible integration of the EBPR in the A-stage of the A/B process, by incorporating an anaerobic zone in order to allow PAO growth. But, PAO bacteria are washed from the system when the SRT is lower than 4 days, so it was needed to work at higher SRTs than those typically used in high-rate systems (SRT<2 days). In addition, real influent was also used in this study, but an external contribution of organic matter was required for the development of the PAO activity.

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31

Guest, Jeremy Scott. "Laboratory Testing of Process Controls for the Mitigation of Toxic Shock Events at Enhanced Biological Phosphorus Removal Wastewater Treatment Plants." Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/44515.

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Toxic shock events can be detrimental to wastewater treatment systems and can result in long-term losses of system performance. If warned of an impending toxic shock, operators would have the opportunity to implement process controls that could help mitigate the effects of the shock event. The objective of this project was to evaluate the effectiveness of a developed corrective action strategy (involving aerobic endogenous respiration) on an enhanced biological phosphorus removal (EBPR) wastewater treatment plant (WWTP) shocked with chlorine. Three identical, laboratory-scale systems were designed to mimic one train of the Long Creek Water Resources Reclamation Facility (WRRF, Gastonia, NC). The basis of this study is a comparative performance analysis among the three trains; a negative control (unshocked and operated normally), a positive control (shocked with hypochlorite and operated normally), and the corrective action (shocked with hypochlorite and process controls implemented). Comparative performance analysis among the three trains was based on effluent quality, performance stability, and biomass kinetics as indicated by rates of respiration and phosphate release and uptake. The shock event and corrective action strategy both inhibited EBPR. After an initial perturbation, the positive control matched the performance of the negative control. The corrective action, however, exhibited significant instability in EBPR performance. Regardless of whether aerobic or anaerobic sludge storage conditions are selected, endogenous respiration will still result in system instability. It is recommended, therefore, that measures be taken to avoid imposing endogenous conditions on isolated sludge during a short-term toxic shock event.
Master of Science

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32

Wylie, Andrew Colin. "Investigation of electrical conductivity as a control parameter for enhanced biological phosphorus removal in a pilot scale sequencing batch reactor." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/7095.

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The relationship between phosphorus (P) concentration and process control parameters was investigated in a pilot scale enhanced biological phosphorus removal (EBPR) sequencing batch reactor (SBR). Datasets were examined to determine whether process control data could be used to detect a (P) removal failure, and P and nitrogen sensors were installed to improve the resolution of their respective measurements of these types of molecules. Track studies were performed to determine whether the electrical conductivity (EC):P relationship that had previously been demonstrated in the lab holds in larger SBR systems: in this relationship EC increases as P is released by polyphosphate accumulating organisms, and decreases as inorganic P is taken up, possibly due to the corresponding transport of the cations magnesium and potassium. The relationship was confirmed, showing that EC could be used as a real-time control parameter to optimize the length of anaerobic and aerobic phases of the SBR in order to maximize energy savings and to decrease the possibility of eutrophication caused by EBPR failure.

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33

Roberts, Ross. "Mapping spontaneous biological phosphorus removal in a membrane bioreactor process without the anaerobic condition : Investigating the effect of alternative external carbon sources." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-287547.

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Phosphorus removal in wastewater treatment is commonly achieved by chemical precipitation, enhanced biological phosphorus removal (EBPR) or a simultaneous combination of the two. A defined anaerobic condition is widely regarded as the critical element to sustain EBPR. However, this study demonstrates that EBPR is indeed occurring in a 4.5 m3/h membrane bioreactor (MBR) pilot plant without a defined anaerobic condition. Although designed for chemical precipitation alone, a low average Fe/P molar ratio (iron dose/phosphorus removed) of 0.9 ± 0.1 suggests that EBPR could be contributing to a simultaneous phosphorus removal. Weekly flow-proportional grab samples through the process showed a phosphate (P) release between the primary anoxic tanks, followed by a larger uptake in the aerobic tanks. In laboratory batch tests with limited acetate supply in the presence of nitrates, the anoxic P-release began and then abruptly stopped whilst the nitrate concentration continued to decrease. This could be explained by denitrifiers out-competing PAOs for soluble substrate since a large P-release occurred when excess acetate was supplied in the presence of nitrates. It is therefore unlikely that PAOs are operating in the pilot despite the presence of nitrates as was concluded in a study with similar spontaneous EBPR observations. Instead, it is suggested that EBPR is enabled by intermittent anaerobic conditions in the primary anoxic tanks due to low nitrate concentrations (< 1 mg NO3/l) recirculating back after post-denitrification. The external carbon source supplied to the pilot was changed from glycerol to ethanol to assess any effect on the spontaneous EBPR. After ethanol had been supplied for 30 days, increased P-release rates were observed in batch tests supplied with ethanol (0.1 to 0.4 mg P/g VSS∙h) and batch tests supplied with acetate (8.6 ± 0.4 to 10.3 ± 0.4 mg P/g VSS∙h). However, the overall consumption of glycerol was less than that of ethanol, whilst the total phosphorus removal and the Fe/P ratio remained similar whether ethanol or glycerol was supplied to the pilot plant. Should operators wish to avoid any possible spontaneous P-release in the post-denitrification step, methanol is recommended as the external carbon source when considering laboratory P-release results, past research and operation costs.
Fosforrening av avloppsvatten uppnås vanligtvis genom kemisk utfällning, enhanced biological phosphorus removal (EBPR) eller en kombination av dessa två samtidig. Ett definierat anaeroba förhållanden betraktas allmänt som det kritiska elementet för att upprätthålla EBPR. Dock visar denna studie att EBPR verkligen förekommer i en pilotanläggning med membranbioreaktor (MBR) utan ett definierat anaeroba förhållanden. Veckovis flödesproportionella stickprover genom processen visade en ökad fosfat (P) halt mellan de primära anoxisk tankarna, följt av ett upptag i de aerobiska tankarna. Även om det är planerat för bara kemisk fosforrening, ett lågt medel Fe/P molförhållande (järndos/fosfor bortagning) på 0,9 ± 0,1 föreslår att EBPR kan bidra till ett samtidigt fosforrening. Laboratorie-P-utsläppningstest bekräftade EBPR-aktivitet med en hög medel P-utsläpp av 9,3 ± 0,9 mg P/g VSS∙h med acetat. Tillsammans indikerar dessa resultat att biologiskt fosforrening kompletterade den kemiska fosforrening under undersökningsperioden. P- utsläppningstest visade att närvaron av nitrater inte påverkade PAO-aktiviteter när acetat tillfördes i överskott. Med begränsad acetattillförsel förhindrade emellertid närvaron av nitrater någon initial P-utsläpp och inga efterföljande fermenteringsbiprodukter observerades. Slutsatsen dras att effektiv nitrifikation-denitrifikation och hög recirkulation resulterar i låga nitrathalt i primär anox tankar. Detta orsakar intermittenta anaerobisk förhållanden som, tillsammans med lämpliga substrathalt i inloppsvatten, möjliggör EBPR att ske. Den externa kolkällan som levererades till MBR-piloten ändrades från glycerol till etanol för att undersöka potentialen att öka EBPR-andelen av fosforrening. P-utsläpp i labbtester med etanol dosering ökade från 0,1 till 0,4 mg P/g VSS∙h och tester med acetat dosering ökade från 8,6 ± 0,4 till 10,3 ± 0,4 mg P/g VSS∙h när slam hade anpassats till etanol i 30 dagar. Vid pilotanläggningens drift konsumerades i alla fall mindre glycerol under dess användningsperiod än etanol, och Fe / P- förhållandet var likadant oavsett om glycerol eller etanol tillsatts. Olika andra kolkällor testades i parallella P-utsläppningstest. VFA producerat genom jäsning av matavfall och primärt slam i ett pågående projekt, och huvudsakligen bestående av kapronsyra, resulterade i den näst högsta P- utsläpp. P-utsläpp från alkoholer var märkbart lägre än VFA-baserade kolkällor. Det betyder att risken är låg för oväntat P-utsläpp i den slutliga biologiska zonen om en alkoholbaserad kollkällan doseras där. Minskad förluftning och en liten dos VFA-baserat substrat i den första biologiska zonen skulle bidra till en betydande EBPR som skulle möjliggöra en ytterligare reducerad basdos av järnsulfat.

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Boontian, Nittaya. "Using the activated sludge model 2d (ASM2d) to understand and predict the phosphorus accumulating organisms mechanism in enhanced biological phosphorus removal in relation to disintegrated sludge as a carbon source." Thesis, Cranfield University, 2012. http://dspace.lib.cranfield.ac.uk/handle/1826/7864.

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Carbon sources are considered as one of the most important factors in the performance of enhanced biological phosphorus removal (EBPR). Disintegrated sludge (DS) can act as carbon source to increase the efficiency of EBPR. This research explores the influence of DS upon phosphorus removal efficiency using mathematical simulation modeling. Activated Sludge Model No. 2d (ASM2d) is one of the most useful of activated sludge (AS) models. This is because ASM2d can express the integrated mechanisms of phosphorus accumulating organisms (PAOs) under aerobic, anaerobic and anoxic conditions. Cont/d.

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Sakamoto, Isabel Kimiko. "Comparação da estrutura de comunidades microbianas presentes em sistemas de lodos ativados modificados para remoção biológica do fósforo em excesso, utilizando a técnica de eletroforese em gel de gradiente desnaturante (DGGE)." Universidade de São Paulo, 2001. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-16022016-131515/.

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O excesso de nutrientes como nitrogênio e fósforo em efluentes de estação de tratamento de esgoto sanitário pode provocar a eutrofização nos corpos d\'aguas receptoras. Esse processo gera efeitos negativos para a engenharia sanitária, dependendo do grau de qualidade e do uso de água requeridos. Para o abastecimento público, são exigidos métodos e processos de tratamentos avançados, quando a fonte hídrica está eutrofizada. Neste sentido, sistemas aeróbios de lodos ativados passaram a se destacar também como removedores de nutrientes por processos biológicos, após sofrerem algumas modificações operacionais. Um meio para otimizar o processo de remoção biológica do fósforo em excesso (EBPR) é promover condições ideais para o crescimento dos organismos acumuladores de fósforo. Esse trabalho teve como objetivo avaliar uma estação piloto de lodos ativados modificados, para a remoção de fósforo em excesso, utilizados no tratamento de esgoto sanitário, localizada na ETE da cidade de Tóquio - Japão. Essa estação piloto constituía-se de três sistemas de reação (1, 2 e 3), sendo que cada sistema era compartimentado e submetido às condições anaeróbia, anóxica e aeróbia. A avaliação dos três sistemas de reação, consistiu na verificação do desempenho deles com relação a DBO e fósforo e monitoramento da estrutura da comunidade microbiana, pela técnica da eletroforese em gel de gradiente desnaturante (DGGE). O desempenho em relação a DBOs (mg/L) nos três sistemas de reação, sempre foi superior a 90% e a eficiência da remoção do fósforo (%) na forma de fosfato (P-PO4 - mg/L) foi superior, em geral, a 70%, considerando os valores de entrada das alimentações e saída no último compartimento dos três sistemas de reação. Verificou-se que a estrutura da comunidade microbiana apresentou uma grande diversidade, devido aos números de bandas padrões encontradas nas amostras analisadas. Observou-se também uma grande similaridade ) da estrutura da comunidade microbiana nos sistemas estudados, possivelmente, relacionada ao mesmo afluente (esgoto sanitário) e ao mesmo tipo de recirculação interna e do lodo. As mudanças das estruturas das comunidades microbianas foram pequenas, diante das mudanças temporais e operacionais. No entanto, observou-se que o sistema foi menos eficiente (parâmetros de desempenho), frente a essas mudanças, o que pode estar mais relacionado à redução das atividades dos microrganismos do que com as estruturas microbianas.
The excess of nutrients such as nitrogen and phosphate in effluents of treatment plants for sanitary sewage can cause eutrophication in the receiving body of water. Given that process generates negative effects for the sanitary engineering depending on the degree of the quality and of the requested use of water. For the public provisioning, methods and processes of advanced treatments are demanded, when the water body is eutrophic. In this sense, aerobic systems of activated sludge have been expanded also to the processes of biological removal of nutrients after some operational modifications. By means of the optimization process of enhanced biological phosphorus removal (EBPR) will promote ideal conditions for the growth of polyphosphate accumulating organisms. This work had as its objective to evaluate a pilot station modified activated sludge, used for the treatment of sanitary sewage, but specifically for the enhanced phosphorus removal, located in the ETE of the city of Tokyo - Japan. These pilot station was constituted of three reaction systems (1, 2 and 3), and each system were composed of compartments and were submitted to anaerobic, anoxic and aerobic conditions. The evaluation of the three reaction systems, consisted of the verification of the performance of the systems with regard to BOD and phosphate which were monitored through microbial community\'s structure, for the biological phosphorus removal technique (DGGE). The performance in relation to the BODS (mg/L) in the three reaction systems was always above 90% and the efficiency of the removal of phosphorus (%) in the form of phosphate (P-PO4 - mg/L) was in general better than 70%, considering the values of influent and effluent from the last compartment of the three reaction systems. It was verified that the microbial community structure presented a great diversity, due to the standard numbers of bands found in the analyzed samples. A great similarity of the microbial community structure was observed in the studied systems, possibly being related to the same influent (domestic sewage) and to the same type of intern recirculation and of the sludge. The changes of the microbial communities structures were small, before the temporary and operational changes. However, it was observed that the system was less effiecient (performance parametrs) front to those changes, what can be more related the reduction of the activities of the microorganisms than with the microbial structures.

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36

Elfving, Erik. "Hydrolys av primärslam för förbättrande av biologisk fosforreduktion vid behandling av hushållsavloppsvatten [Hydrolysis of primary sludge for enhancement of biological phosphorus removal in household wastewater]." Thesis, Linköping University, Department of Water and Environmental Studies, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-3997.

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Hammarby Sjöstad is a new district of southern Stockholm built with focus on reduced environmental impact by recirculation of materials and sustainability. The environmental goals aim to cut the water consumption by half and a separate storm water treatment. Thus, the wastewater will be more concentrated and will originate from the households only. The Sjöstad project includes the idea of a local treatment plant for the household wastewater. To evaluate this possibility, Sjöstadsverket, an experimental treatment plant was constructed. New wastewater treatment processes are tested and evaluated and compared to conventional methods including both aerobic and anaerobic treatment processes.

One of the aerobic treatment processes includes enhanced biological phosphorus removal (EBPR or Bio-P) as the method for the removal of phosphorus. In biological phosphorus removal the wastewater is alternately being exposed to anaerobic and aerobic conditions, which favours a certain bacteria, which can accumulate more phosphorus than is required for their growth. For this phosphorus accumulation the bacteria need volatile fatty acids (VFA) to cover their energy demand, but normally there is a shortage in VFA in the incoming wastewater.

The main purpose of this master thesis work has been to create the best possible conditions in order to produce VFA by hydrolysis and fermentation of primary sludge. In this way the organic material in the incoming wastewater can be used in biological phosphorus removal.

The sludge temperature, total solids (TS) and retention time are regarded as important parameters for a successful biological phosphorus removal and a laboratory study was set up to investigate these conditions for the wastewater at the Hammarby Sjöstad experimental plant. These laboratory-scale hydrolysis experiments showed that high temperature and high TS favours VFA-production. The results have also shown that four to five days retention time is suitable at a process temperature higher than 23°C, but also that the retention time likely should be extended at lower temperatures.

In a full-scale process experiment, primary sludge was pumped from a primary clarifier to a hydrolysis tank and then back to the primary clarifier. The hydrolysis gave rise to increased VFA-production when TS was increased. A temperature difference between the primary sludge and the hydrolysis sludge of 3°C was observed. The reason behind the difference has not been determined, but is considered important, since the temperature affects the VFA-production. Further on, analyses with gas chromatograph (GC) have shown that acetate has been the most frequently occurring VFA, although significant levels of other VFA, such as propionate, has also been detected.

Phosphorus release tests in laboratory-scale, where phosphorus was released during an anaerobic phase and taken up during an aerobic phase, proved that biological phosphorus removal occurred at the full-scale experimental train.

The full-scale hydrolysis experiment has shown that the VFA contribution by the hydrolysis tank to the biological phosphorus removal was low. The main reason is that the sludge-flow through the hydrolysis tank has been insignificant compared to the incoming wastewater flow. The problem is most likely connected to the incoming wastewater characteristics, since the low share of suspended solids (SS) entailed that not enough organic material in the primary clarifier settled.

I figur 57 på sidan 76 stämmer inte trendlinjernas ekvationer i den tryckta versionen. Dessa är nu korrigerade i den elektroniska versionen, så att rätt ekvationer finns i den aktuella figuren.

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37

Coma, Bech Marta. "Biological nutrient removal in SBR technology: from floccular to granular sludge." Doctoral thesis, Universitat de Girona, 2011. http://hdl.handle.net/10803/32025.

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Biological nutrient removal has been studied and applied for decades in order to remove nitrogen and phosphorus from wastewater. However, more anthropogenic uses and the continued demand for water have forced the facilities to operate at their maximum capacity. Therefore, the goal of this thesis is to obtain more compact systems for nutrient removal from domestic wastewater. In this sense, optimization and long-term stabilization of high volume exchange ratios reactors, treating higher volumes of wastewater, have been investigated. With the same target, aerobic granular sludge was proposed as a reliable alternative to reduce space and increase loading rates in treatment plants. However, the low organic loading rate from low-strength influents (less than 1 Kg COD•m-3d-1) results in slower granular formation and a longer time to reach a steady state. Because of that, different methodologies and operational conditions were investigated in order to enhance granulation and nutrient removal from domestic wastewater.
L’estudi de l’eliminació biològica de nutrients s’ha dut a terme durant dècades. Tot i això, la influencia de l’home i l’augment de la demanda d’aigua han forçat a les instal•lacions a treballar a la seva capacitat màxima. Així, l’objectiu de la tesi és obtenir sistemes més compactes per a l’eliminació de nutrients de les aigües residuals. En aquest sentit, s’ha investigat l’optimització i estabilització de reactors amb alts volums d’intercanvi, tractant més aigua. Amb el mateix objectiu, el fang granular aeròbic va ser proposat com una alternativa fiable per tal de reduir l’espai i incrementar les càrregues de les depuradores. Tot i això, la granulació amb influents de baixa càrrega (menors a 1 Kg dQO•m-3d-1) resulta més lenta i més dificultosa alhora d’obtenir l’estat estacionari. Per aquesta raó es van investigar diferents metodologies i condicions d’operació per tal de millorar la granularció i l’eliminació de nutrients de les aigües urbanes.

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CHOU, KAI-HAO, and 周楷皓. "Short-term and Long-term Performance of Enhanced Biological Phosphorus Removal (EBPR) System Exposed to Oxytetracycline (OTC)." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/pegx8j.

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碩士
國立雲林科技大學
環境與安全衛生工程系
106
In the experiment of the pulse input of oxytetracycline (OTC) concentration in the influent, along with four acetate and propionic fed anaerobic/oxic sequencing batch reactors, we discuss the response of the biological phosphorus removal system under the pulse input of different initial OTC concentration (including 10, 20, 30 and 40 mg/L). The result indicated that OTC has no influence on the efficacy of phosphorus removal system if pulse input concentration is below 30mg/L. The main effect is the inhibition on phosphorus release in anaerobic phase and the increase in soluble microbial products (SMPs). When OTC concentration reached over 40 mg/L, OTC would inhibit the whole anaerobic/aerobic phosphorus metabolism. It caused evident decrease in the population of phosphate accumulating organisms (PAOs) responsible for phosphorus metabolism and the bad efficacy of phosphorus removal in the system. In phosphate removal efficiency failure stage, it showed that the inhibition of phosphorus uptake in aerobic phase was more obvious than the phosphate release in anaerobic phase. Simultaneously, the output concentration of COD at the end of aerobic phase increased significantly to 80 mg/L because of the use of anaerobic phase residual acetate to aerobic phase. Therefore, this SMPs is substrate-utilization-associated products. Moreover, OTC would inhibit PAOs uptake of acetate; however, OTC had no inhibition of PAOs uptake of propionic which resulted in the substantial increase in 3HV composition of intracellular PHAs. In the experiment on the stepped increase in OTC concentration in the influent, we utilize an acetate and propionic fed anaerobic/oxic sequencing batch reactor to discuss the effect of influent OTC concentration on biological phosphorus removal system and the system affordability on OTC concentration by periodically stepped increase in influent OTC concentration. In addition, in order to understand the influence of salinity on the failure at phosphorus removal, we attempted to recover the efficacy of system by reducing influent OTC concentration. The result indicated that when the influent OTC concentration is below 0.075mg/L, there was no effect on the efficacy of phosphorus removal. The main effect is the inhibition of phosphorus release and the increasing use of glycogen. It decreased slightly in the proportion of PAOs and the system gained advantages from GAOs gradually. When OTC concentration reached 0.1mg/L, OTC would inhibit anaerobic/aerobic phosphorus removal and glycogen metabolism which caused the evident decrease in the population of PAOs and GAOs and failure at phosphorus removal in the system. After the influent oxytetracycline concentration was removed, the system of water quality was improved which costed ten times of SRT to reach steady state. When PAOs and GAOs in the system are both inhibited, VFAs remaining in the anaerobic phase are taken up during the aerobic phase. It indicated that OTC had less inhibition of Xh in the system and the order in population inhibition of OTC is PAOs> GAOs> Xh. In phosphate removal efficiency failure stage, it showed that aerobic phosphorus uptake inhibition was more evident than anaerobic phosphorus release inhibition and it failed to remove phosphorus absolutely. In conclusion, the main reason of the failure in aerobic phosphorus removal is the OTC inhibition of ΔBiomass/ ΔPHAs.

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Santos, Jorge Miguel Martins. "A Novel Integrated Metabolic Activated Sludge Model for Enhanced Biological Phosphorus Removal Processes: Development, Calibration, Validation and Application." Doctoral thesis, 2020. http://hdl.handle.net/10362/106688.

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Enhanced biological phosphorus removal (EBPR) facilities achieve low effluent phosphorus (P) levels (below 1 g P.m-3) for long periods of time. However, these facilities are often affected by unpredictable upsets that increase their operational costs and reduce the potential to recover P from downstream processes. Thereby, these facilities need to have access to reliable tools, capable of dynamically predicting EBPR performance and diagnosing plant upsets. To address this need, a novel integrated metabolic activated sludge model, the META-ASM, was developed with a robust single set of default parameters to describe the activity of the key organisms and processes relevant to EBPR systems. The advances regarding EBPR mechanisms investigated over the last twenty years were integrated in the META-ASM model to overcome various shortcomings of existing EBPR models. Special attention is given to the effect of operational conditions on the competition between polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs), along with the capability of PAOs and GAOs to denitrify, the metabolic shifts as a function of storage polymer concentration for each group, the role of these polymers in endogenous processes, and a better description of the fermentation process. The model was calibrated and validated against 34 data sets describing different EBPR dynamics obtained from bench-scale batch tests inoculated with lab-scale enriched PAO-GAO cultures and full- scale sludge from different EBPR facilities. The overall strong correlations obtained between the predicted and the measured EBPR profiles demonstrated that this new model reduces calibration efforts and is capable of predicting the microbial and chemical transformations over a wide range of operational and environmental conditions, supporting the robustness of the unique default parameter set that was generated. A performance comparison between META-ASM and literature models also demonstrated that existing models require extensive parameter changes and have limited predictive power to describe different EBPR dynamics. The capacity of the META-ASM model to describe the long-term performance of a full-scale 3- stage Phoredox (A2/O) EBPR system and to be used as an operational diagnostic tool was evaluated in a 1336-day long-term dynamic simulation, while its performance was compared with the ASM-inCTRL model, a version based on the Barker & Dold model. Overall, the META-ASM provided a better description of PAOs active biomass and storage polymers and was a more powerful operational diagnostic tool for plant upsets. Viable troubleshooting scenarios were simulated to mitigate the upsets caused by the high aerobic hydraulic retention times (HRTs) and low organic loading rates (OLRs) of the plant. This thesis demonstrates that the META-ASM model is a powerful operational diagnostic tool for EBPR systems, capable of predicting plant upsets, optimising performance and evaluating new process designs.

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40

Barreiros, Srđana Kolaković Oliveira. "Investigation of key operational factors impacting phosphorus removal and recovery from wastewater treatment plants." Doctoral thesis, 2022. http://hdl.handle.net/10362/132398.

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Nutrient and micropollutant removal, as well as resource recovery, are some of the major current concerns in the wastewater treatment field. Wastewater treatment plants (WWTPs) need solutions to quickly tackle these emerging problems and operate as sustainably as possible. Therefore, this thesis focused on providing insight into some of the major challenges in these fields, such as: i) factors influencing efficient enhanced biological phosphorus removal (EBPR) and its microbial community structure; ii) the biotransformation of an important micropollutant (diclofenac) in the EBPR process and iii) phosphorus and carbon solubilisation from WWTP sludge for resource recovery. EBPR is a complex process where specific bacteria are used for phosphorus removal from the bulk liquid. The most important polyphosphate accumulating organism (PAO) is “Candidatus Accumulibacter phosphatis”, that comprises of phylogenetically different Types, clades and subclades, whose metabolism can be influenced by specific conditions. A reactor enriched with Accumulibacter (> 85 %) was operated for over a one-year period, and identification at the sub-clade level was necessary to correlate the specific identity of the Accumulibacter group with the observed reactor performance. The carbon feeding rate proved to be crucial for the expression of different metabolisms, where a fast-feeding rate resulted in a mixed phosphate/glycogen accumulating metabolism leading to poor P removal (< 30 %) that correlated with clusters ii and iii of Accumulibacter IIc, while a slow carbon feeding rate resulted in complete phosphorus removal and an abundance of cluster i. This work showed that some organisms commonly recognised as PAO do not promote efficient phosphorus removal and there is a need to recharacterize the organisms within the Accumulibacter group. Removal of micropollutants is another emerging concern, especially since some micropollutants such as diclofenac have been shown to be near-recalcitrant in conventional WWTPs. Additionally, some physical/chemical processes have been shown to produce transformation products that are more toxic than the parent compound. Diclofenac biotransformation was investigated in the EBPR process, where the metabolic pathway and toxicity of diclofenac by-products were also assessed. Although Accumulibacter did not appear to transform diclofenac as efficiently as other bacteria (e.g., nitrifiers), it was found to still contribute towards its detoxification. Furthermore, a correlation was observed between the quantity of diclofenac biotransformation and Accumulibacter Type, which could suggest that enrichment of Type II Accumulibacter can stimulate diclofenac biodegradation in wastewater treatment. Finally, resource recovery is one of the major initiatives in the wastewater treatment field. WWTPs are no longer seen as just treatment facilities, but also present opportunities to recover other added-value products and provide more sustainable solutions. Phosphorus is an irreplaceable nutrient and a scarce resource that must be recovered from phosphorus rich waste streams. Biological acidification was tested in this study as an additional step within conventional WWTPs and was shown to have great potential to solubilise up to 80 % of phosphorus and produce on average 0.35 g CODVFA/gVS that could be used in subsequent processes for the production of phosphorus rich fertilizers or bioplastics, respectively.
A remoção de nutrientes e micropoluentes, bem como a recuperação de recursos, são algumas das principais preocupações atuais na área do tratamento de águas residuais. As estações de tratamento de águas residuais precisam de soluções para combater rapidamente esses problemas emergentes e operar da forma mais sustentável possível. Por esse motivo, o objectivo desta tese foi identificar alguns dos principais desafios nestas áreas, tais como: i) fatores que influenciam a remoção biológica eficiente de fósforo e respetiva composição da comunidade microbiana; ii) a biotransformação de um importante micropoluente (diclofenac) no processo de remoção biológica de fósforo e iii) solubilização de fósforo e carbono de lamas de tratamento de águas residuais com objectivo de recuperação de recursos. A remoção biológica do fósforo é um processo complexo em que bactérias específicas são usadas para a remoção do fósforo da parte liquida. O organismo acumulador de polifosfato (PAO) mais importante é a “Candidatus Accumulibacter phosphatis”, composta por diferentes tipos filogenéticos, clades e subclades, cujo metabolismo das diferentes espécies é influenciado por condições especificas. Neste trabalho, um reator enriquecido em Accumulibacter (> 85%) foi operado por um período superior a um ano, durante o qual a identificação de uma espécie , ao nível do subclade, foi feita de forma a correlacionar a identidade específica do grupo Accumulibacter com o desempenho do reator. A taxa de alimentação de carbono provou ser crucial para a expressão de diferentes metabolismos. Uma taxa de alimentação rápida resultou em um metabolismo misto de acumulação de fosfato/glicogênio, levando a uma baixa remoção de P (< 30%), o que se correlacionou com os clusters ii e iii, enquanto uma taxa de alimentação de carbono lenta levou a um metabolismo de acumulação de polifosfato típico, resultando na remoção completa do fósforo e de uma abundância do cluster i dentro da mesma Accumulibacter IIc. Este trabalho mostrou que alguns organismos habitualmente reconhecidos como PAO não promovem uma remoção eficiente de fósforo, verificando-se assim a necessidade de reclassificar os organismos que são PAOs dentro do grupo Accumulibacter. A remoção de micropoluentes é outra preocupação emergente, especialmente porque alguns micropoluentes, como o diclofenaco, mostraram ser recalcitrantes em estações de tratamento de águas residuais convencionais. Foi demonstrado que alguns processos físicos/químicos produzem produtos de transformação mais tóxicos do que o composto original. A biotransformação do diclofenaco foi investigada simultaneamente com a remoção biológica do fósforo, onde a via metabólica e a toxicidade dos subprodutos do diclofenaco também foram avaliadas. Embora a Accumulibacter não pareça biotransformar o diclofenaco tão eficientemente quanto outras bactérias (por exemplo, nitrificantes), ainda assim contribui para a sua desintoxicação ao produzir subprodutos de menor toxicidade do que o próprio diclofenaco. Além disso, foi observada uma correlação entre a quantidade de biotransformação de diclofenaco e o tipo de Accumulibacter, o que pode sugerir que o enriquecimento de Accumulibacter do tipo II pode estimular a biodegradação do diclofenaco no tratamento de águas residuais. Por fim, a recuperação de recursos é uma das principais iniciativas na área de tratamento de águas residuais. As estações de tratamento de águas residuais não são apenas vistas como estações de tratamento, apresentando também oportunidades de recuperação de outros produtos de valor acrescentado e de soluções mais sustentáveis. O fósforo é um nutriente insubstituível e um recurso escasso que deve ser recuperado de correntes de resíduos ricos em fósforo. A acidificação biológica foi testada neste estudo como uma etapa adicional a incluir em estações de tratamento de águas residuais convencionais e demonstrou ter o potencial de solubilizar até 80 % do fósforo e produzir 0,35 g CODVFA/g VS, que poderá ser usado em processos subsequentes para a produção de fertilizantes ricos em fósforo ou bioplásticos, respetivamente.

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41

Yuan, Qiuyan. "Fermentation – Enhanced Sustainable Biological Phosphorus Removal." 2012. http://hdl.handle.net/1993/5038.

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The success of enhanced biological phosphorus removal depends on the constant availability of volatile fatty acids (VFAs). To reduce costs of purchasing external carbon, waste streams would be a preferred source for nutrient removal. VFAs were shown to vary in the incoming sewage and fermentate from primary sludge (PS). Another available source of organic to generate VFAs is waste activated sludge (WAS). The effect of solids retention time and biomass concentration, as well as the effect of temperature and requirement for mixing on generation of VFA from the fermentation of WAS were investigated. It was found that VFA yields from sludge fermentation increased with SRT. At the longest SRT of 10 days improved biomass degradation resulted in the highest soluble to total COD ratio and the highest VFA yield. WAS fermentation was found highly temperature-dependent. The overall VFA–COD concentration in the non-mixed reactors was much lower than the mixed reactors. The study of fermentation of PS, WAS and a mixture of WAS and PS demonstrated that PS fermentation predictably generated a significantly higher amount of soluble COD than WAS. Co-fermentation of WAS with PS enhanced soluble COD production and increased the release of phosphate and ammonium. Fermentation of combined PS and WAS sludge generated a concentration of phosphate high enough to allow phosphorus recovery as struvite The effect of using glycerol as an external carbon source in biological phosphorus removal was investigated. Using glycerol directly resulted in the failure of the process which maintained enhanced biological phosphorus removal. When glycerol was co-fermented with waste activated sludge, significant VFA production was observed. By 2 | P a g e supplying the system with the VFA-enriched supernatant of the fermentate, biological phosphorus removal was enhanced. It was concluded that, if glycerol was to be used as external carbon source for biological phosphorous removal, the effective approach was to ferment glycerol with waste activated sludge. According to the cost analysis, the economic benefit of WAS fermentation can be demonstrated in three ways: 1) cost saving in external carbon addition; 2) cost saving in sludge handling; 3) revenue from phosphorus. At current condition, the value of the recovered P product is insignificant relative to the cost of chemicals that required for recovery and capital cost of the facilities. However, P recovery becomes important when the sustainability take into account.

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42

Chaparro, Sean K. "Controlling biosolids phosphorus content in enhanced biological phosphorus removal reactors." 2002. http://catalog.hathitrust.org/api/volumes/oclc/50249836.html.

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Thesis (M.S.)--University of Wisconsin--Madison, 2002.
Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 89-99).

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43

Zhang, Zhe. "Modelling of membrane enhanced biological phosphorus removal : determining model parameters." Thesis, 2004. http://hdl.handle.net/2429/15213.

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Parameter determination and wastewater characterization are crucial for modeling of the membrane enhanced biological phosphorus removal process (MEBPR). The batch test is a preferred approach for assessing the model components. Sludge samples from an MEBPR and a simplified University of Cape Town, South Africa (UCT) processes were analyzed in parallel to estimate the growth yield, decay rate and maximum specific growth rate of the heterotrophic biomass, in addition to investigating the difference between the two processes in terms of the microbial activity, by comparing the growth yield, decay coefficient and maximum specific growth rate of the heterotrophic biomass. Methods reported in the literature were used in this study. Carbon, nitrogen and phosphorus fractions of influent wastewater at the UBC pilot plant were characterized to provide the basic information prior to computer simulation. This study presents and discusses results of parameter estimation and wastewater characterization from available data. A slightly lower growth yield value was observed in the MEBPR process compared with the simplified UCT process. The model decay coefficient results based on the two processes were very close. However, different values of maximum specific growth rate of heterotrophic biomass were found between the MEBPR and the simplified UCT processes. The concentrations of readily biodegradable substrate and fermentation products were in the typical range; and the ratios of COD/TKN and COD/TP in the wastewater would allow for excellent nitrogen and phosphorus removal in the MEBPR process; while the higher fractions of inert particulate matter and slowly biodegradable substrates in the wastewater may affect the performance of the MEBPR process. The experimental results suggested that characterization is very important for modeling the membrane enhanced biological phosphorus removal process, and the parameters that are wastewater-specific must be determined for the use of modeling. More studies on the shear force, mass transfer, and mixing conditions in the MEBPR process should be conducted to investigate their effects on microbial activities.

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Silva, Ana Sofia Alves Brites da. "Modelling and optimization of a full-scale enhanced biological phosphorus removal System." Master's thesis, 2015. http://hdl.handle.net/10362/56815.

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This work in this thesis was conducted in partnership with the company ÁGUAS DO ALGARVE, and had as main objective to characterise the performance of the enhanced biological phosphorus removal wastewater treatment in Boa vista, through the utilisation of an activated sludge model and aim to test various operating factors to optimize the process. Characterization of the sewage influent and effluent was performed in order to evaluate the content of organic matter (i.e., chemical oxygen demand - COD) and its biodegradability (Biological Oxygen Demand - BOD) as well as nutrients (such as nitrogen (N) and phosphorus (P)). The influent COD was also characterized in terms of particulate, biodegradable and inert fractions. This information was used as input in the GPS-X program, where the ASM2d model was tested. The biological treatment system of the Boavista plant consists of an extended aeration activated sludge system with nitrification/denitrification and biological phosphorus removal. For model calibration purposes, a through, 6-day sampling campaign was conducted in June 2015, where all relevant flow rates and CDO, N and P fractions were measured in the influent, effluent and recycles. The calibrated model was able to describe very well the performance during this period. This calibration model was then applied to describe the performance data during the year 2014. A substantial deviation was found between the model predicts and the measured process data. This derivation is likely at least partially attributable to the different aeration regimes employed in 2014 vs 2015, as well as the cessation of iron coagulant addition in 2015, which could necessitate recalibration of the ASM2d model. A simulation study carried out with and without iron sulfate addition suggested that the Boavista plant could eliminated iron sulfate addition without an appreciable increase in effluent phosphorus concentration. This hypothesis was indeed supported by the effluent phosphorus data achieved at Boavista, which actually experienced a decrease in effluent p levels after ceasing iron sulfate addition in 2015 as compared to 2014, thereby lowering operational costs at theWWTP.

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Chang, Wei-Chin, and 張維欽. "Filamentous Bulking Control and Process Dynamic Control in Enhanced Biological Phosphorus Removal System." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/28445729987229830225.

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博士
國立中央大學
環境工程學系
85
ABSTRACTIncorporating phosphate into the biomass is the only feasible means of removing phosphate from wastewater in an enhanced biological phosphorus removal (EBPR) system, accounting for why biomass-liquid seperation primarily influences the overall system''s performance. This study investigates the behavior of biomass-liquid separation in the EBPR process under steady-state and dynamic influent wastewater loading.In the steady-state experiments, a specific parameter, i.e. specific residual substrate utilization rate , is developed to evaluate the filamentous bulking potential in the design of an enhanced biological phosphorus removal (EBPR) process. Continuous- flowpilot-plant experiments employing synthetic wastewater are performed at different SRTs (5, 10, 15 days) and anaerobic: aerobic volume ratios, Van:Va (1:9, 1:4, 1:2.3). Experimental results reveal that surpass anaerobic phosphate release concentration to be an indicator of metabolic selection for bulking control, owing to its strong correlation with SVI. Whereas, the effect of on SVI can not be consistently explained under different SRTs. This comparison implies that the specific utilization of residual substrate left for filaments in aerobic zone is the primary factor influencing SVI. Furthermore, eliminating the access of filaments in the aerobic zone to substrate exerts a more influence on SVI than favoring poly-p microorganisms: the main floc-formers in the EBPR process. These findings infer that, in the design stage of the EBPR process, carbon sequestration by poly-p microorganisms in the anaerobic zone should be maximized so as to yield a lower in the aerobic zone. Also, the simultaneous process requirements of phosphorus removal and bulking controlare demonstrated in the design procedure of EBPR process by combining with the kinetic modeling of phosphorus removal. More, this study presents a specific process control strategy, i.e. sludge pre-recycle control, for a dynamic EBPR system by intergratedly considering two factors: (1) appropriately controlling F/M ratio in the anaerobic zone and (2) eliminating hydraulic shock in the secondary clarifier. Fuzzy logic inference is also introduced while constructing an on-line controller owing to the ill- defined characteristics of the dynamic EBPR system. For comparison, continuous-flow pilot plant experiments with automatic monitoring and real-time control facilities are performed using two control strategies: sludge pre-recycle control and conventional (F/M)an control. Experimental results indicate that similar effluent ranges of dissolved COD and dissolved phosphate can be obtained from the two strategies owing to their similar (F/M)an ratios. However, reliability analysis reveals that sludge pre-recycle control significantly improves the effluent total SS concentration than conventional (F/M)an control because of the reduction of hydraulic loading in the clarifier. Therefore, sludge pre-recycle control is highly desired owing to the ability to reduce the hydraulic loading in the secondary clarifier at peak loading period while, at the same time, maintain a similar (F/M)an ratio in the biological reactor as conventional (F/M)an control. Moreover, statistical correlation of effluent qualities indicates that suspended COD and suspended phosphorus contents are proportional to total SS. Based on these findings, we can infer that when in the operation stage, the effluent total SS control is a critical consideration of system performance. Such an inference again verifies the effectiveness of sludge pre-recycle control: introducing the hydraulic loading factor into the control strategy.

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46

Perez-Feito, Rafael. "Simultaneous enhanced biological phosphorus removal and polyhydroxyalkanoates recovery population dynamics and reactor performance /." 2001. http://catalog.hathitrust.org/api/volumes/oclc/50080535.html.

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47

He, Shaomei. "Population structure and gene expression of Candidatus Accumulibacter in enhanced biological phosphorus removal." 2008. http://www.library.wisc.edu/databases/connect/dissertations.html.

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48

Carvalheira, Mónica Isabel Gonçalves. "The effect of key process operational conditions on enhanced biological phosphorus removal from wastewater." Doctoral thesis, 2014. http://hdl.handle.net/10362/14295.

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Enhanced biological phosphorus removal (EBPR) is the most economic and sustainable option used in wastewater treatment plants (WWTPs) for phosphorus removal. In this process it is important to control the competition between polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs), since EBPR deterioration or failure can be related with the proliferation of GAOs over PAOs. This thesis is focused on the effect of operational conditions (volatile fatty acid (VFA) composition, dissolved oxygen (DO) concentration and organic carbon loading) on PAO and GAO metabolism. The knowledge about the effect of these operational conditions on EBPR metabolism is very important, since they represent key factors that impact WWTPs performance and sustainability. Substrate competition between the anaerobic uptake of acetate and propionate (the main VFAs present in WWTPs) was shown in this work to be a relevant factor affecting PAO metabolism, and a metabolic model was developed that successfully describes this effect. Interestingly, the aerobic metabolism of PAOs was not affected by different VFA compositions, since the aerobic kinetic parameters for phosphorus uptake, polyhydroxyalkanoates (PHAs) degradation and glycogen production were relatively independent of acetate or propionate concentration. This is very relevant for WWTPs, since it will simplify the calibration procedure for metabolic models, facilitating their use for full-scale systems. The DO concentration and aerobic hydraulic retention time (HRT) affected the PAO-GAO competition, where low DO levels or lower aerobic HRT was more favourable for PAOs than GAOs. Indeed, the oxygen affinity coefficient was significantly higher for GAOs than PAOs, showing that PAOs were far superior at scavenging for the often limited oxygen levels in WWTPs. The operation of WWTPs with low aeration is of high importance for full-scale systems, since it decreases the energetic costs and can potentially improve WWTP sustainability. Extended periods of low organic carbon load, which are the most common conditions that exist in full-scale WWTPs, also had an impact on PAO and GAO activity. GAOs exhibited a substantially higher biomass decay rate as compared to PAOs under these conditions, which revealed a higher survival capacity for PAOs, representing an advantage for PAOs in EBPR processes. This superior survival capacity of PAOs under conditions more closely resembling a full-scale environment was linked with their ability to maintain a residual level of PHA reserves for longer than GAOs, providing them with an effective energy source for aerobic maintenance processes. Overall, this work shows that each of these key operational conditions play an important role in the PAO-GAO competition and should be considered in WWTP models in order to improve EBPR processes.

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49

Kuo, Chun-Hsing, and 郭俊興. "Long-term and short-term effect of influent substrate change on enhanced biological phosphorus removal." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/16636569961455983290.

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碩士
雲林科技大學
環境與安全工程系碩士班
97
Anaerobic-oxic (A/O) activated sludge system has been experimentally confirmed to be capable of removing phosphorous from wastewater. But the phosphorous removal ability of the A/O system may be hindered for some reasons. The competition between GAOs (Glycogen Accumulating Organisms, GAOs) and PAOs (Phosphate Accumulating Organisms, PAOs) is considered to be one of the most important reasons. The deterioration of A/O systems has frequently been observed when glucose is fed as the carbon source, which GAOs have proliferated. However, Successful EBPR operation has been achieved in some studies fed with glucose as the carbon source. However, it is commonly believed that glucose is fermented to VFAs such as acetate and lactate prior to substrate uptake by PAOs. In this research, glucose was used as the major substrate to investigate if it could directly induce a long-term stable EBPR performance. The result showed that when carbon source of A/O system was switched from acetate to glucose, short-term cultivation led to good phosphorus performance and simultaneously discovered that glucose was fermentation to lactic acid. But under the long-term operation the A/O system deteriorated gradually, due to the probale dominance of GAOs. Besides, this research further constructed another A/O system with a switch of carbon source from complex substrate to glucose, the result also discovered that the phosphorus function under long-term taming also gradually lose. When A/O system with a switch in carbon source from acetate to lactate, the experiment confirmed that PAOs, compares to GAOs, have superiority of the lactic acid ingestion. Therefore, when glucose is used as a major carbon source GAOs can be induces proliferation. This research further constructed two A/O systems, by separately changing their substrate from acetate to CODAcetate:CODglucose = 1:1 and the CODAcetate:CODglucose = 1:3. When mixture of acetate and glucose was supplied as the carbon substrate in an A/O system, PAOs can absorb the acetate rapidly, but not influenced by GAOs. Under the long-term operation A/O system maintain the phosphorus function normally. In addition, aerobic sludge P content, aerobic carbohydrate content, anaerobic PHAs stores of the system maintained at normal range. When influent phosphorus load to suddenly increase 1.5 times , A/O system maintains stable phosphorus function by regulation of metabolism function,. However, when phosphorus load suddenly increases 2.5 times, the A/O system must transforma the structure of microbial communities (approximately 16 day) to achieve the system steady state. When phosphorus load suddenly increases to 3.5 times, in 3rd days the phosphorus function rapidly worsen. When A/O system adapts the high phosphorus load suddenly submitted to low phosphorus load, the system still maintain stable phosphorus removal.

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50

Lin, You-Sheng, and 林祐陞. "Response of enhanced biological phosphorus removal system to the step-increase of salinity in the influent." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/47205232709729361666.

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碩士
國立雲林科技大學
環境與安全衛生工程系
103
Saline wastewater mainly generated by using the seawater or saline water as alternative water to solve the water scarcity problem in dryland, and there is also some industries produce saline wastewater. Past research showed that the saline wastewater would affect the biological treatment systems, while most of the research focused on organic and nutrient removal, and there were few studies focused on enhanced biological phosphorus removal system. Therefore, to discuss how the influent salinity affects the enhanced biological phosphorus removal system and the affordability of system, it set an acetate-fed anaerobic/oxic sequencing batch reactor and operated the influent salinity by step-increase. In addition, it tried to recover the efficacy of system by reducing influent salinity and seeding PAOs rich sludge. The results showed that the efficacy of system would not be affected at lower salinity (1 and 2 g/L), and it would improve the specific acetate uptake rate and specific phosphorus release rate, but it made more use of glycogen and showed energy source changed in anaerobic phase. While the influent salinity was 4 g/L, the system failed to remove phosphorus absolutely, and it made the influent acetate uptake incompletely and mixed liquid suspended solids decreased. While the influent salinity reduced, it showed no improved to biological phosphorus removal, but it improved by seeding PAOs rich sludge. In order to evaluate the efficacy of sewage treatment by taking the EBPR process, it set a sewage fed anaerobic/oxic sequencing batch reactor and did influent wastewater characterization. The results showed that sewage in Douliu had lack of organic amount, and it had higher NH4+-N than classic sewage. The results of SBR operating showed that there was no PAOs metabolic behavior discovered, and parts of NO3--N and DO which generated by nitrification and aeration in aerobic phase were returned to anaerobic phase, and consumed the carbon source in the influent. The results of using nitrification inhibitor and controlling the dissolved oxygen showed that the amount of NO3--N and DO in returned flow were decreased, and it found that there was phosphorus release and uptake in anaerobic phase, but it still had phosphorus remained in the effluent, furthermore, because nitrification inhibitor is biodegradable, the inhibition would be lose effectiveness, and caused NO2--N produced in low DO condition. The results of adding molasses broth showed that while adding 125 mg/L VFAs into influent, system would have enough carbon source to remove NO3--N and DO in anaerobic phase, and used for phosphorus removal, simultaneously.

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Dissertations / Theses on the topic 'Enhanced biological phosphorus removal (EBPR)'

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