Zurück zur Übersicht

Decentralized urine treatment with the nitritation/anammox process (DUNOX)

Gesuchsteller/in Udert Kai
Nummer 125133
Förderungsinstrument Projektförderung (Abt. I-III)
Forschungseinrichtung Eawag
Hochschule Eidg. Anstalt für Wasserversorgung, Abwasserreinigung und Gewässerschutz - EAWAG
Hauptdisziplin Andere Gebiete der Ingenieurwissenschaften
Beginn/Ende 01.04.2009 - 30.09.2012
Bewilligter Betrag 208'593.00
Alle Daten anzeigen

Alle Disziplinen (4)

Andere Gebiete der Ingenieurwissenschaften
Experimentelle Mikrobiologie

Keywords (6)

Microbial ecology; Nitrogen removal; Nitrous oxide; Urine separation; Decentralized wastewater treatment; Nitric Oxide

Lay Summary (Englisch)

Lay summary
LeadNovel decentralized reactors can be the key to a more efficient and affordable wastewater treat-ment in cities. This project investigates, whether a new biological process - partial nitritation and anammox - is suitable for nitrogen removal in on-site reactors.BackgroundCombining sewers and centralized wastewater treatment has worked reasonably well for the industrialized part of the world, but for a number of reasons the success in developing and fast industrializing countries has been very limited. Recent research has shown that separation of wastewater streams at the source and decentralized treatment would be more resource-efficient, cheaper and easier to implement. Especially the separate treatment of urine would strongly reduce environmental pollution. Lately, a biological process - one-stage partial nitrita-tion and anammox - has been developed that removes nitrogen more efficiently than conven-tional processes. Lab experiments have shown that the process is suitable to treat urine, but a better understanding of the microbial transformation processes is needed to operate reliably on-site reactors.MethodsPilot reactors - rotating biological contactors - will be operated under controlled but changing environmental conditions. The main process parameters will be monitored continuously. Ge-netic information about the microbial community and the microbial activity will be measured with microbiological methods. To determine the requirements for process stability, the datasets will be evaluated with computer models.GoalsThe overall goal of the project is to determine the conditions for stable biological nitrogen re-moval from urine in small on-site reactors. We want to understand how the microbial commu-nity reacts on sudden changes in environmental conditions. We aim to analyze the importance of microbial diversity for process stability and we want to elucidate which factors determine whether the bacterial interactions support or destabilize the nitrogen removal process. Special emphasis will be put on the conditions that foster the release of harmful intermediates such as nitric oxide (NO) and nitrous oxide (N2O).SignificanceDecentralized reactors for nutrient removal can be essential tools to fight the deterioration of aquatic environments worldwide. From a scientific point of view, combining biotechnology and microbial ecology is a highly promising approach to better understand stress and stability in biological processes. A better understanding of the microbial interactions will not only help to increase process stability, it will also help to reduce emissions of environmentally harmful gases such as NO and N2O.
Direktlink auf Lay Summary Letzte Aktualisierung: 21.02.2013

Verantw. Gesuchsteller/in und weitere Gesuchstellende


Name Institut


Temperature Dependence and Interferences of NO and N2O Microelectrodes Used in Wastewater Treatment
(2012), Temperature Dependence and Interferences of NO and N2O Microelectrodes Used in Wastewater Treatment, in Environmental Science and Technology, 46(4), 2257-2266.
Regime Shift and Microbial Dynamics in a Sequencing Batch Reactor for Nitrification and Anammox Treatment of Urine
(2011), Regime Shift and Microbial Dynamics in a Sequencing Batch Reactor for Nitrification and Anammox Treatment of Urine, in Applied and Environmental Microbiology, 77(17), 5897-5907.


Gruppe / Person Land
Formen der Zusammenarbeit
University Ghent Belgien (Europa)
- vertiefter/weiterführender Austausch von Ansätzen, Methoden oder Resultaten
- Forschungsinfrastrukturen
EMPA Schweiz (Europa)
- vertiefter/weiterführender Austausch von Ansätzen, Methoden oder Resultaten
- Publikation
- Forschungsinfrastrukturen

Wissenschaftliche Veranstaltungen

Aktiver Beitrag

Titel Art des Beitrags Titel des Artikels oder Beitrages Datum Ort Beteiligte Personen
IWA Nutrient Removal and Recovery 2012 Conference 23.09.2012 Harbin, China
69th Annual Congress of the Swiss Society for Microbiology 24.11.2010 Zurich
13th International Symposium on Microbial Ecology 22.08.2010 Seattle, USA
Performance and microbial population dynamics of a nitritation/anammox reactor treating urine 11.04.2010 Lisbon, Portugal
Kleines Institutstreffen 31.01.2010 Stuttgart, Germany
ASPD 5, specialised conference in microbial population dynamics in biological wastewater treatment 27.11.2009 Aalborg, Denmark
3rd Swiss Microbial Ecology Meeting 28.01.2009 Einsiedeln
Alliance for Global Sustainability, Annual Meeting 26.01.2009 Zurich

Verbundene Projekte

Nummer Titel Start Förderungsinstrument
144498 Decentralized urine treatment with the nitritation/anammox process Part 2 (DUNOX-2) 01.10.2012 Projektförderung (Abt. I-III)
144498 Decentralized urine treatment with the nitritation/anammox process Part 2 (DUNOX-2) 01.10.2012 Projektförderung (Abt. I-III)
128778 Confocal Microscopy at Eawag 01.09.2010 R'EQUIP


With this project we want to contribute to the development of reliable small scale reactors for on-site nitrogen removal from wastewater. For many cities worldwide, small decentralized reactors would be more efficient and affordable than large wastewater treatment plants and com-bined sewer systems. However, small on-site reactors have to achieve the same or even a better efficiency of sanitation, nutrient removal and degradation of harmful organic substances. Source-separation might be the key to reliable decentralized wastewater treatment. Previous research at Eawag has demonstrated that urine separation has a high potential for efficient and reliable nutrient removal from wastewater. In this project we want to investigate the one-stage nitritation/anammox process for decentralized nitrogen removal from urine. The process is resource-efficient and full-scale reactors for digester supernatant treatment have been operated successfully on several wastewater treatment plants. However, small on-site reactors pose new challenges. The process stability and resilience tends to be small, because of a low microbial diversity. However, no personnel or expensive instruments are available for process control. In addition to the constrains due to the reactor size, urine is an inhospitable environment for most bacteria. It contains very high ammonia and salt concentrations, a high pH and considerable amounts of toxic organic substances. Process instabilities can cause the accumulation of nitric oxide, which is toxic for bacteria. Process instabilities can also lead to the release of nitrous oxide, which is a potent green-house gas and a catalyzer for ozone depletion in the stratosphere. Previous experiments have shown that nitritation/anammox treatment of urine is possible, but a good understanding of the process parameters and the microbial population is necessary.In this project we will combine biotechnology and microbial ecology to answer four fundamental questions: First, is the performance of the nitritation/anammox sufficiently high for small on-site reactors? Second, what are the basic requirements for process stability? Third, is ni-trous oxide production critical? Finally, which are the microbial pathways and the bacteria that dominate the nitrogen removal?Two different reactor setups will be used: sequencing batch reactors (SBR) as a tool to research process performance and population dynamics and rotating biofilm contactors (RBC) as a potential system to be used on-site. The start-up phase, a steady-state phase and controlled stress experiments will be closely monitored with chemical and microbiological analysis and with batch experiments for turnover measurements. PCR based methods will be used to determine the diversity of the microbial community, to identify the bacteria and to quantify the main key players and the enzymatic activity. The use of confocal laser scanning microscopy combined with FISH will allow to specify the spatial organization of the bacteria in the biofilm. Chemical and microbial data will be used to set up a computer model, which will be used to determine the conditions for stable process control. Process stability will also be assessed based on ecological indicators calculated from microbiological fingerprints (DGGE, T-RFLP). 15N marked nitrogen compounds will be used to identify the main pathways for nitrogen conver-sion. Gas selective electrodes and FTIR measurements will be applied to monitor the accumu-lation of nitric oxide and the release of nitrous oxide. We expect that this research project will contribute significantly to the development decentral-ized reactors for nutrient removal. Thereby, it will help to fight eutrophication worldwide. From a scientific point of view, we are convinced that a combination of biotechnology and microbial ecology is a highly promising approach to questions of stress and stability in biological processes. With this project, we intend to establish a closer collaboration between wastewater engineers and microbial ecologists at Eawag.