Print Email Facebook Twitter Photo-oxygenation for nitritation and the effect of dissolved oxygen concentrations on anaerobic ammonium oxidation Title Photo-oxygenation for nitritation and the effect of dissolved oxygen concentrations on anaerobic ammonium oxidation Author Mukarunyana, Brigitte (University of Rwanda; IHE Delft Institute for Water Education) van de Vossenberg, Jack (IHE Delft Institute for Water Education) van Lier, J.B. (TU Delft Sanitary Engineering; IHE Delft Institute for Water Education) Van Der Steen, Peter (IHE Delft Institute for Water Education) Date 2018-09-01 Abstract Removal of nitrogen from wastewater without using electricity consuming aerators was previously observed in photo-bioreactors with a mixed algal-bacterial biomass. Algammox is the particular process based on algae, ammonium oxidizing organisms and anammox bacteria. In this research the activity of anammox bacteria in such an oxygen-producing environment was tested, as well as the effect of short-duration increase in dissolved oxygen (DO) to values potentially inhibiting anammox activity. Sequencing batch photo-bioreactors were fed with settled domestic wastewater enriched with ammonium (200 mg NH4 +-N/L) and exposed to light within the photosynthetic active range with intensity of about 500 μmol/m2·s. Each cycle consisted of 12 h illumination and 12 h darkness. A well-settling biomass (10 days solids retention time) developed that carried out nitritation, nitrification and anammox. Ammonium removal rate during the light period was 4.5 mg N-NH4 +/L·h, equal to 858 mg N-NH4 +/m2·h or 477 mg N-NH4 +/(mol photons). When the reactors were aerated for 3 h to temporarily increase the DO, anammox was inhibited at bulk DO values larger than 0.4–1.0 mg/L. For almost oxygen saturated conditions, recovery time was about 9 days. Algammox photo-bioreactors are therefore able to overcome short periods of oxygen stress, provided they occur only occasionally. Subject Anammox inhibitionMicroalgaeNitritationPhoto-bioreactorWastewater To reference this document use: http://resolver.tudelft.nl/uuid:31a4b098-1a7b-462b-8c2f-36c94d6bd914 DOI https://doi.org/10.1016/j.scitotenv.2018.04.082 Embargo date 2018-10-10 ISSN 0048-9697 Source Science of the Total Environment, 634, 868-874 Bibliographical note Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Part of collection Institutional Repository Document type journal article Rights © 2018 Brigitte Mukarunyana, Jack van de Vossenberg, J.B. van Lier, Peter Van Der Steen Files PDF 1_s2.0_S0048969718312464_main.pdf 1.4 MB Close viewer /islandora/object/uuid:31a4b098-1a7b-462b-8c2f-36c94d6bd914/datastream/OBJ/view