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Wyniki wyszukiwania dla: NITROGEN REMOVAL
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Kinetics of nitrogen removal processes in constructed wetlands
PublikacjaThe aim of this paper is to present a state-of-the-art review of the kinetics of nitrogen removal in constructed wetlands. Biological processes of nitrogen removal from wastewater can be described using equations and kinetic models. Hence, these kinetic models which have been developed and evaluated allow for predicting the removal of nitrogen in treatment wetlands. One of the most important, first order removal model, which is...
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Pathways of Nitrogen Removal in Hybrid Treatment Wetlands
PublikacjaHybrid Treatment Wetlands (HTWs) are composed of two or more filters with different modes of flow, allowing the benefits of both types of bed to be combined, resulting in better effluent quality (nitrogen and organic compounds removal). Such a heterogeneous environment creates possibilities for different mechanisms of nitrogen removal. The objective of the present study was to investigate the removal of nitrogen versus a range...
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The occurrence and role of Nitrospira in nitrogen removal systems
PublikacjaApplication of the modern microbial techniques changed the paradigm about the microorganisms performing nitrification. Numerous investigations recognized representatives of the genus Nitrospira as a key and predominant nitrite-oxidizing bacteria in biological nutrient removal systems, especially under low dissolved oxygen and substrate conditions. The recent discovery of Nitrospira capable of performing complete ammonia oxidation...
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Nitrogen removal in two technologies of wastewater treatment
PublikacjaW pracy przedstawiono problematykę usuwania związków azotu ze ścieków w świetle wymogów prawnych Polski i Unii Europejskiej. Problem został scharakteryzowany w odniesieniu do dwóch typów oczyszczalni ścieków - pracujących w całkowicie różnych skalach: dużej oczyszczalni ścieków miejskich Gdańska (Oczyszczalnia ścieków ''Wschód'') oraz oczyszczalni hydrofitowych, przeznaczonych do oczyszczania względnie niewielkich objętości ścieków...
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Incorporation of the sulfur cycle in sustainable nitrogen removal systems - A review
PublikacjaIn wastewater treatment systems, sulfur (S) removal processes are generally based on heterotrophic sulfate (SO42−) reduction by sulfate reducing bacteria and S-dependent autotrophic denitrification by sulfur oxidizing bacteria. A combination of either two cycles (N and S) or three cycles (N, S and C) appears to be a viable approach to sustainable wastewater treatment, resulting in energy savings and reduction of sludge production....
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Nitrogen removal in vertical flow constructed wetlands: influence of bed depth and high nitrogen loadings
PublikacjaThe aim of the study was to evaluate the nitrogen removal and its effects on the plant’s growth and leaves morphology. using two subsurface vertical flow (VF bed), with different depths (0.24 m2 × 0.70 m; 0.24 m2 × 0.35 m) and nitrogen load increments. The VF bed were planted with Vetiveria zizanioides, filled with light expanded clay aggregates (Leca®NR 10/20) and fed in parallel mode with synthetic wastewater. High ammonium nitrogen...
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Development of models for nitrogen-removal processes in subsurface flow constructed wetlands
PublikacjaThis paper summarizes recent progress in modelling approach of subsurface flow constructed wetlands (SSF CWs), focusing on nitrogen removal processes.
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Modeling the pH effects on nitrogen removal in the anammox-enriched granular sludge
PublikacjaThe aim of the study was to determine the pH effects on nitrogen removal in the anammox-enriched granular sludge. The experimental data were extracted from a 4L completely-mixed batch reactor with the granular sludge at different initial pH values (6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5) and constant temperature T=30℃. Simulations were run in GPS-X 6.4 using a comprehensive mechanistic model Mantis2. Two kinetic parameters, including...
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MODELING THE pH EFFECTS ON NITROGEN REMOVAL IN THE ANAMMOX-ENRICHED GRANULAR SLUDGE
PublikacjaThe aim of the study was to determine the pH effects on nitrogen removal in the anammox-enriched 10 granular sludge. The experimental data were extracted from a 4L completely-mixed batch reactor with the 11 granular sludge at different initial pH values (6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5) and constant temperature 12 T=30℃. Simulations were run in GPS-X 6.4 using a comprehensive mechanistic model Mantis2. Two 13 kinetic parameters,...
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Combined partial denitrification/anammox process for nitrogen removal in wastewater treatment
PublikacjaRecently, the combined partial denitrification and anammox (PD/anammox) has received special attention as a viable alternative for N removal using organic matter present in municipal wastewater. In comparison with conventional nitrification-denitrification, PD/anammox provides enormous opportunities to achieve sustainable wastewater treatment due to the lack of dissolved oxygen (DO) demand, a smaller amount of organic carbon (C)...
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Application of mechanistic and data-driven models for nitrogen removal in wastewater treatment systems
PublikacjaIn this dissertation, the application of mechanistic and data-driven models in nitrogen removal systems including nitrification and deammonification processes was evaluated. In particular, the influential parameters on the activity of the Nitrospira activity were assessed using response surface methodology (RSM). Various long-term biomass washout experiments were operated in two parallel sequencing batch reactor (SBR) with a different...
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Impact of influent wastewater quality on nitrogen removal rates in multistage treatment wetlands
PublikacjaNitrogen removal in treatment wetlands is influenced by many factors, and the presence of electron donors (biodegradable organic matter) and electron acceptors (nitrate ions) is the main limiting one; for obtaining these conditions, multistage treatment wetlands (MTWs) are required, where an extensive nitrification can be obtained in the first stages under aerobic conditions leaving then to the following anoxic/anaerobic stages...
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Comparison of two model concepts for simulation of nitrogen removal at a full-scale biological nutrient removal pilot plant
PublikacjaCelem badań było porównanie zdolności predykcyjnych dwóch mechanistycznych modeli procesu osadu czynnego (ASM1 i ASM3). W tym celu wykorzystano bazę danych empirycznych z pilotowej oczyszczalni ścieków Gummerwald w Hanowerze (Niemcy). Oba badane modele prognozowały szczytowe stężenia azotu amonowego na poziomie >8 gN/m3 w ciągu, którego obciążenie hydrauliczne wzrastało czterokrotnie w porównaniu do okresu bezdeszczowego. Prognozowany...
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Dynamic simulation as a tool for evaluation of the nitrogen removal capabilities at the "Gdańsk-Wschód" WWTP
PublikacjaCelem badań było przedstawienie możliwości zastosowania złożonego modelu biokinetycznych ASM2d do symulacji procesu usuwania azotu w oczyszczalni ścieków ''Wschód'' w Gdańsku. Szybkość procesów nitryfikacji i denitryfikacji została wyznaczona w warunkach laboratoryjnych za pomocą tzw. testów zlewkowych. Wyniki tych badań zostały wykorzystane do kalibracji modelu, w trakcie której zmieniano wartości tylko 5 parametrów kinetycznych....
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Reliability of nitrogen removal processes in multistage treatment wetlands receiving high-strength wastewater
Publikacjareatment wetlands have been proved to be more effective than conventional treatment processes in case of high-strength wastewater containing high concentrations of ammonium nitrogen and recalcitrant organic matter. In this study nitrogen removal processes and reliability of nitrogen removal at two identical pilot-scale multistage treatment wetlands (MTWs) receiving real, non-synthetic wastewater were discussed. The wastewater discharged...
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An advanced synergy of partial denitrification-anammox for optimizing nitrogen removal from wastewater: A review
PublikacjaAnammox is a widely adopted process for energy-efficient removal of nitrogen from wastewater, but challenges with NOB suppression and NO3− accumulation have led to a deeper investigation of this process. To address these issues, the synergy of partial denitrification and anammox (PD-anammox) has emerged as a promising solution for sustainable nitrogen removal in wastewater. This paper presents a comprehensive review of recent developments...
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The Polish perspective on adopting EU standards nitrogen removal at large WWTPs - case studies
PublikacjaW związku z przyjęciem nowych regulacji prawnych w zakresie usuwania azotu w dużych oczyszczalniach ścieków (>100 000 RM), potrzebne są wiarygodne i dokładne informacje na temat wymiarowania stref anoksycznych w komorach osadu czynnego. Badania zostały przeprowadzone w oczyszczalniach Gdańsk-Wschód oraz Gdynia-Dębogórze. Ich celem było porównanie szybkości denitryfikacji określonej w warunkach laboratoryjnych oraz obliczonej na...
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Integrating conventional nitrogen removal with anammox in wastewater treatment systems: Microbial metabolism, sustainability and challenges
PublikacjaThe various forms of nitrogen (N), including ammonium (NH4+), nitrite (NO2−), and nitrate (NO3−), present in wastewaters can create critical biotic stress and can lead to hazardous phenomena that cause imbalances in biological diversity. Thus, biological nitrogen removal (BNR) from wastewaters is considered to be imperatively urgent. Therefore, anammox-based systems, i.e. partial nitrification and anaerobic ammonium oxidation (PN/anammox)...
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Industrial wastewater as an external carbon source for optimization of nitrogen removal at the "Wschod" WWTP in Gdansk (Poland)
PublikacjaCarbon source alternatives for denitrification belong to the highest research area priorities as they allow to optimize N removal within the existing capacities. In particular, some food industry effluents appear to be good candidates for such alternatives due to their high C/N ratios and high content of readily biodegradable organic fraction. The aim of this study was to determine the immediate effects of dosing different types...
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The Polish perspective on adopting EU standards for nitrogen removal at large WWTP´s - case studies.
PublikacjaW pracy przedstawiono porównanie szybkości procesu denitryfikacji mierzonej w warunkach laboratoryjnych z obliczeniami dokonanymi na podstawie bilansu masy dla bioreaktorów w skali technicznej. Doświadczenia wykonano w oczyszczalni ścieków'' Wschód w Gdańsku i ''Dębogóra'' w Gdyni.
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Integration of the sulfate reduction and anammox processes for enhancing sustainable nitrogen removal in granular sludge reactors
PublikacjaThe Anammox and Sulfate Reduction Ammonium Oxidation processes were compared in two granular sequencing batch reactors operated for 160 days under anammox conditions. It was hypothesized that increasing the concentration of SO42− may positively influence the rate of N removal under anaerobic conditions and it was tested whether SO42− reduction and anammox occur independently or are related to each other. The cooperation of N-S...
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Importance of the combined effects of dissolved oxygen and pH on optimization of nitrogen removal in anammox-enriched granular sludge
PublikacjaThe combined effects of dissolved oxygen (DO) and pH on nitrogen removal were investigated in a laboratory-scale sequencing batch reactor (SBR) with anammox-enriched granular sludge obtained from a nitritation/anammox system. The highest specific nitrogen removal rate (SNRR) (1.1 gN gVSS−1 d−1) was observed under non-aerated conditions, resulting in the nitrogen removal efficiency of 81.6%. Although nitrogen removal was readily...
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Sustainable nitrogen removal in anammox-mediated systems: Microbial metabolic pathways, operational conditions and mathematical modelling
PublikacjaAnammox-mediated systems have attracted considerable attention as alternative cost-effective technologies for sustainable nitrogen (N) removal from wastewater. This review comprehensively highlights the importance of understanding microbial metabolism in anammox-mediated systems under crucial operation parameters, indicating the potentially wide applications for the sustainable treatment of N-containing wastewater. The partial...
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Optimization of the Aeration Strategies in a Deammonification Sequencing Batch Reactor for Efficient Nitrogen Removal and Mitigation of N2O Production
PublikacjaIn deammonification systems, nitrite-oxidizing bacteria (NOB) suppression and nitrous oxide (N2O) mitigation are two important operational objectives. To carry out this multivariable analysis of response, a comprehensive model for the N cycle was developed and evaluated against experimental data from a laboratory-scale deammonification granular sludge sequencing batch reactor. Different aeration strategies were tested, and the manipulated...
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Dissolved and colloidal organic nitrogen removal from WWTP effluents and reject waters using physical-chemical processes
PublikacjaFour physical-chemical processes were compared in terms of the efficiencies of dissolved and colloidal organic nitrogen (DON and CON) removal from the secondary effluents (SE) and reject water from full-scale biological nutrient removal activated sludge systems. Adsorption on activated carbon was most efficient and allowed to remove from the SE up to 80% and 100% of DON and CON, respectively. High efficiencies of DON removal from...
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Potential and limits of landfill leachate treatment in a multi-stage subsurface flow constructed wetland – evaluation of organics and nitrogen removal
PublikacjaConstructed wetlands have potential of treating wastewater of poor biodegradability. The performance of a multistage sub-surface flow wetland treating municipal landfill leachate was assessed during three years of operation. During the study three research periods with different operation conditions were established. The hydralic loads, operation mode of vertical flow beds and type of treated wastewater (raw leachate – leachate...
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Enhancing nitrogen removal in the partial denitrification/anammox processes for SO4− - Rich wastewater treatment: Insights into autotrophic and mixotrophic strategies
PublikacjaThe investigation of partial denitrification/anammox (PD/anammox) processes was conducted under autotrophic (N–S cycle) and mixotrophic (N–S–C cycle) conditions over 180 days. Key findings revealed the remarkable capability of SO42--dependent systems to produce NO2− effectively, supporting anaerobic NH4+ oxidation. Additionally, SO42− served as an additional electron acceptor in sulfate reduction ammonium oxidation (SRAO). Increasing...
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Comparison of nitrogen and VFA removal pathways in autotrophic and organotrophic anammox reactors
PublikacjaOrganotrophic anammox is a promising process for treating both nitrogen and organic containing wastewater than that of the traditional autotrophic anammox for sole nitrogen removal. However pathways of nitrogen removal particularly at metagenomic level in both processes are still unknown. Here we report, metabolic pathways of nitrogen removal in two lab-scale sequencing batch reactors (SBR), one autotrophic and another organotrophic...
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Influence of the boron doping level on the electrochemical oxidation of raw landfill leachates: advanced pre-treatment prior to the biological nitrogen removal
PublikacjaThe electrochemical oxidative treatment of landfill leachates (LLs) containing high amounts of ammonia nitrogen and organic matter was used as a promising method, prior to biological processes, to achieve the final effluent quality that would be acceptable by current regulations. The deposited boron-doped diamond electrodes (BDDs) with different boron doping concentrations (10000, 5000 and 500 ppm of B) were applied as anodes....
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Nitrogen removal via the nitrite pathway during wastewater co-treatment with ammonia-rich landfill leachates in a sequencing batch reactor
PublikacjaThe biological treatment of ammonia-rich landfill leachates due to an inadequate C to N ratio requires expensive supplementation of carbon from an external carbon source. In an effort to reduce treatment costs, the objective of the study was to determine the feasibility of nitrogen removal via the nitrite pathway during landfill leachate co-treatment with municipal wastewater. Initially, the laboratory-scale sequencing batch reactor...
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Influence of composition of raw wastewater on removal of nitrogen compounds in multistage treatment wetlands
PublikacjaInfluence of composition of raw wastewater on the efficiency of organic matter and nitrogen removal in multistage treatment wetlands has been examined. Commonly used indicators, like COD/BOD5 and BOD5/TN ratio, determining wastewater susceptibility to biodegradation in conventional treatment technologies were assessed. It was confirmed that multistage treatment wetland may be used for treatment of wastewater with high loads of...
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Nitrogen monitoring in atmospheric deposition and its removal from municipal and industrial wastewater
PublikacjaBadano zmiany stężenia azotu w opadach atmosferycznych oraz warunki usuwania azotu ze ścieków komunalnych i przemysłowych. Badano wpływ wybranych sulfonamidów na proces nitryfikacji oraz oznaczano ich stopień biodegradacji. Stwierdzono, że sulfonamidy są substancjami, które hamują procesy biologicznego oczyszczania ścieków, jak również w niskim stopniu ulegają biodegradacji.
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Removal of organic matter and nitrogen in an horizontalsubsurface flow (HSSF) constructed wetland undertransient loads
PublikacjaA monitoring campaign in a horizontal subsurface flow constructed wetland under the influence of transient loads of flow-rate, organic matter, nitrogen and suspended solids showed an irregular removal of COD and TSS and lower both removal efficiencies and mass removal rates than the ones observed in other studies for similar operating conditions. This circumstance is associated to the presence of large amount of particulate organic...
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Characteristics and fate of organic nitrogen in municipal biological nutrient removal wastewater treatment plants
PublikacjaThe aim of this study was to investigate the occurrence and fate of colloidal and dissolved organic nitrogen (CON and DON) across biological nutrient removal (BNR) activated sludge bioreactors. Primary and secondary effluent total nitrogen (TN) measurements and component fractionation, CON and DON concentration profiles across BNR bioreactors, and laboratory batch experiments with the process mixed liquor were carried out at several...
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Impact of aeration conditions on the removal of low concentrations of nitrogen in a tertiary partially aerated biological filter
PublikacjaA submerged biological aerated filter (BAF) partially aerated was used to study the removal of low concentrations of ammonia nitrogen (0.3 g N/m3 to 30.5 g N/m3) typically found in nutrient enriched river and lake waters, and treated effluents. Four series of experiments were performed with a synthetic wastewater at ammonia loading rates between 6 g N/m3 d and 903 g N/m3 d and C/N ratios from 2 to 20. The results showed that ammonia...
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Removal of nitrogen from wastewater: Unsolved problems and possible solutions with partial denitrification/anammox systems
PublikacjaAbstract Nitrate (NO3−) is more stable than ammonia (NH4+) and nitrite (NO2−) among the majority of emerging pollutants in wastewater that can harm the ecosystem by depleting oxygen and water quality, thereby posing environmental and human health risks. Despite anaerobic ammonium oxidation (anammox) being a common method for nitrogen (N) removal from wastewater, it leaves behind residual NO3− of around 11 %. Maintaining the stability...
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Efficient removal of dyes and proteins by nitrogen-doped porous graphene blended polyethersulfone nanocomposite membranes
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Biomass Production and Removal of Nitrogen and Phosphorus from Processed Municipal Wastewater by Salix schwerinii: A Field Trial
PublikacjaIn many Baltic regions, short-rotation willow (Salix spp.) is used as a vegetation filter for wastewater treatment and recycling of valuable nutrients to upsurge bioeconomy development. In this context, a four-year field trial (2016–2019) was carried out near a wastewater treatment plant in eastern Finland (Outokumpu) to investigate the effect of the processed wastewater (WW) on biomass production as well as the nutrients uptake...
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Evaluation of the simultaneous removal of organic matter, nitrogen and suspended solids in a sshf constructed wetland in capinha, Portugal
PublikacjaCelem pracy była ocena systemu hydrofitowego z podpowierzchniowym przepływem wody (SSHF) usytuowanego w miejscwości Capinha w Portugalii, głównie pod względem usuwania substancji organicznej oraz związków azotu. Podczas czteromiesięcznego monitoringu obiekt wykazał niereguralność w suswaniu zawiesiny ogólnej oraz substancjo organicznej wyrażonej w ChZT. Szybkość usuwania zanieczyszczeń organicznych wynosiła 28 g ChZT/m2d. Uzyskaną...
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Nitrogen oxides removal from hydrogen flue gas using corona discharge in marine boilers: Application perspective
PublikacjaThis paper focuses on the combustion of hydrogen in boilers, as it appears to be a more effective method than using fuel cells for heating purposes due to higher boiler efficiency. One of the main disadvantages of hydrogen combustion in air is NOx formation. Therefore, the authors decided to introduce corona discharge as an inno- vative technique to clean hydrogen flue gas by effectively reducing NOx levels. The method involves...
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Strategies for mitigating nitrous oxide production and decreasing the carbon footprint of a full-scale combined nitrogen and phosphorus removal activated sludge system
PublikacjaNitrous oxide (N2O) emitted from biological nutrient removal activated sludge systems contributes significantly to the total carbon footprint of modern wastewater treatment plants. In the present study, N2O production and emissions were experimentally determined in a large-scale plant (220,000 PE) employing combined nitrogen (N) and phosphorus (P) removal. As a modelling tool, the Activated Sludge Model 2d (ASM2d) was extended...
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Wpływ warunków ciśnieniowej filtracji na przebieg biologicznego usuwania azotu amonowego z wody w procesie nitryfikacji = Effect of pressure filtration conditions on nitrification process used for ammonia nitrogen removal from water
PublikacjaW pracy przedstawiono wyniki badań laboratoryjnych nad wpływem podwyższonego, zmiennego ciśnienia (do 0,8 MPa) na przebieg usuwania azotu amonowego z wody na nitryfikacyjnym złożu filtracyjnym. Wykazano, że ani podwyższone ciśnienie, ani jego zmiany nie wpływają hamująco na przebieg procesów nitryfikacji. Stwierdzono pozytywny wpływ płukania filtrów biologicznych na usuwanie azotu amonowego z wody.
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Przebieg wpracowywania kwarcowych złóż filtracyjnych przeznaczonych do usuwania manganu i azotu amonowego z wód podziemnych.The course of ripenining of quartz sand filter beds used for manganese and ammonium nitrogen removal from the groundwaters.
PublikacjaPrzeprowadzone badania wykazały, ze czas wpracowywania się kwarcowego złoża filtracyjnego w procesie odmanganiania i nitryfikacji trwał od 7 do 8 tygodni (złoże wpracowywało się jednocześnie w obu procesach) Wpracowanie uzyskano filtrując napowietrzoną wodę podziemną o stosunkowo wysokich stężeniach manganu (0,6 - 1,1 mg/l) i azotu amonowego (0,4 - 1,4 mgN/l) i niewielkich stężeniach żelaza (poniżej 0,5 mg/l). Po wpracowaniu...
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Removal of ammonia nitrogen from groundwater during nitrification processes using pressure filters = Usuwanie azotu amonowego z wód podziemnych w procesie nitryfikacji na filtrach ciśnieniowych
PublikacjaW pracy zaprezentowano wyniki badań w skali ułamkowo technicznej nad wpływem podwyższonego i zmiennego ciśnienia (do 0,4 MPa) na przebieg usuwania amoniaku z wód podziemnych, w procesie nitryfikacji, w złożu filtracyjnym. Ustalono, że wszystkie filtry badawcze, zarówno ciśnieniowe jak i grawitacyjny, wymagały adaptacji do zmienionego składu filtrowanej wody. Okres adaptacji filtrów ciśnieniowych był dłuższy, niż dla filtra grawitacyjnego....
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Pathways of nitrogen compounds depletion in hybrid constructed wetlands
PublikacjaHybrid Constructed Wetlands are composed of two or more filters with mixed flow direction of sewage. Apparently in the HCWS the benefits of both types of bed are merged, resulting in better effluent quality (organic and nitrogen componds removal). Such heterogeneous environment creates possibilities for different ways of nitrogen "disappearing". The objective of the present study was to compare the removal of nitrogen with accompanying...
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Mainstream shortcut N removal modeling current status and perspectives
PublikacjaThis work gives an overview of the state-of-the-art in modelling of short-cut processes for nitrogen removal in mainstream wastewater treatment and presents future perspectives for directing research efforts in line with the needs of practice. The modelling status for deammonification (i.e., anammox-based) and nitrite-shunt processes is presented with its challenges and limitations. The importance of mathematical models for considering...
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Application of H2O2 to optimize ammonium removal from domestic wastewater
PublikacjaThe paper presents the results of application of hydrogen peroxide (H2O2) for the optimization of the effects of ammonia nitrogen removal from domestic wastewater. The investigations were carried out at a model wastewater treatment plant consisting of a preliminary sedimentation tank and a sand filter with a horizontal flow of wastewater at a constant hydraulic load of 1.44 L/day. The efficiency of ammonia nitrogen removal was...
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Effects of Different Aeration Modes on Ammonia Removal from Sludge Digester Liquors in the Nitritation-Anammox Process
PublikacjaSludge digester liquors can be responsible for up to one third of the nitrogen load to the biological step of wastewater treatment plants (WWTPs). The conventional process for ammonia removal via two sequential processes, i.e. nitrification and denitrification, is increasingly being challenged by a one-step process in which ammonium is oxidized directly to nitrogen gas e.g. ammonium oxidation (anammox) process. In this novel process,...
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Nitrogen conversion during treatment of various type of wastewater in multistage treatment wetlands
PublikacjaThe objective of this investigation was to recognize nitrogen speciation during wastewater treatment in three multistage TWs (MTWs), which are assuming more a most effective in nitrogen removal than single stage TWs. Carried out investigations and analysis enable for determination of conditions, relationships and processes responsible for nitrogen conversions in subsequent stages of MTWs. In treated wastewater and reject water...
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The efficiency and technological reliability of biogenic compounds removal during long-term operation of a one-stage subsurface horizontal flow constructed wetland
PublikacjaThe paper presents the results of a study of the efficiency and technological reliability of total nitrogen and total phosphorus removal during long term operation of a one-stage constructed wetland system with subsurface horizontal wastewater flow. The flow rate of the wastewater treatment plant was 1.2m3/d during the research period. Physical and chemical analyses of raw wastewater and treated effluent were carried out in the...