Simultaneous nitrification, denitrification and phosphorus removal in a continuous-flow moving bed biofilm reactor alternating microaerobic and aerobic conditions

• Published in: Bioresource technology Vol. 310; p. 123453
• Main Authors: Iannacone, Francesca, Di Capua, Francesco, Granata, Francesco, Gargano, Rudy, Esposito, Giovanni
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.08.2020
• Subjects: Biofilms; Bioreactors; Denitrification; Intermittent aeration; MBBR; Microaerobic-aerobic cycle; Nitrification; Nitrogen; Phosphorus; Phosphorus removal; Sewage; Simultaneous nitrification denitrification; Waste Disposal, Fluid; Microaerobic-aerobic cycle; Intermittent aeration; MBBR; Phosphorus removal; Simultaneous nitrification denitrification
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2020.123453

[Display omitted] •SNDPR was studied in a continuous-flow intermittent-aeration MBBR (IAMBBR).•DOC and TIN removals were 100% and 62% at feed C/N 3.6 and DO range 0.2–3 mg L−1.•The microaerobic-aerobic cycle determined a P-PO43− removal up to 81%.•Nitrifiers and P-accumulating denitrifiers coexisted in the MBBR biofilm.•Hydrogenophaga and Dokdonella could carry out P removal under aerobic conditions. A continuous-flow moving bed biofilm reactor (IAMBBR) alternating microaerobic and aerobic conditions was used to remove carbon, nitrogen and phosphorus through simultaneous nitrification and denitrification coupled to phosphorus removal (SNDPR). The IAMBBR was operated under different dissolved oxygen (DO) ranges (0.2–2, 0.2–3 and 0.2–4 mg L−1) and feed C/N ratios (2.8, 3.6 and 4.2) at HRT of 1 day. At a DO range of 0.2–3 mg L−1 and feed C/N ratio of 3.6, the IAMBBR achieved simultaneous removal of dissolved organic carbon (DOC), total inorganic nitrogen (TIN) and P-PO43− with average efficiencies of 100%, 62% and 75%, respectively. Illumina sequencing revealed the coexistence of nitrifiers and P-accumulating denitrifiers (e.g. Hydrogenophaga) in the IAMBBR biofilm. Batch activity tests showed that phosphorus uptake did not occur under stable anaerobic or anoxic conditions, nor under aerobic conditions in absence of nitrate.