Shortcut nitrification-denitrification and biological phosphorus removal in acetate- and ethanol-fed moving bed biofilm reactors under microaerobic/aerobic conditions

Francesca Iannacone; Francesco Di Capua; Francesco Granata; Rudy Gargano; Giovanni Esposito

doi:10.1016/j.biortech.2021.124958

Shortcut nitrification-denitrification and biological phosphorus removal in acetate- and ethanol-fed moving bed biofilm reactors under microaerobic/aerobic conditions

Bioresour Technol. 2021 Jun:330:124958. doi: 10.1016/j.biortech.2021.124958. Epub 2021 Mar 11.

Authors

Francesca Iannacone¹, Francesco Di Capua², Francesco Granata³, Rudy Gargano³, Giovanni Esposito⁴

Affiliations

¹ Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, via Gaetano di Biasio 43, 03043 Cassino, Italy. Electronic address: francesca.iannacone@unicas.it.
² Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, via Claudio 21, 80125 Naples, Italy; Department of Civil, Environmental, Land, Building Engineering and Chemistry, Polytechnic University of Bari, Via E. Orabona 4, 70125 Bari, Italy.
³ Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, via Gaetano di Biasio 43, 03043 Cassino, Italy.
⁴ Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, via Claudio 21, 80125 Naples, Italy.

PMID: 33756183
DOI: 10.1016/j.biortech.2021.124958

Abstract

This study investigated the feasibility of coupling simultaneous partial nitrification and denitrification (SPND) to biological phosphorus removal in continuous-flow intermittently-aerated moving bed biofilm reactors (MBBRs) fed with different carbon sources, i.e. ethanol and acetate. Bacterial cultivation at pH 8.2 (±0.2), 26-28 °C and SRT of 4 day and microaerobic/aerobic MBBR operation allowed to achieve average dissolved organic carbon (DOC), total inorganic nitrogen (TIN) and P-PO₄^3- removal efficiencies (REs) of 100%, 81-88% and 83-86% at HRT of 1 day, dissolved oxygen (DO) range of 0.2-3 mg L^-1 and feed C/N and C/P ratios of 3.6 and 11, respectively. Acetate supplementation favored a diversified microbial community, while overgrowth of heterotrophs was observed when increasing feed C/N ratio in ethanol-fed MBBR. Illumina sequencing displayed the presence of putative phosphorus accumulating organisms (PAOs) such as Hydrogenophaga and Pseudomonas in MBBR biofilm and suspended biomass, whereas no typical NOB was identified during the study.

Keywords: Intermittent aeration; MBBR; Phosphorus removal; Putative PAO; Shortcut nitrification and denitrification.

MeSH terms

Acetates
Biofilms
Bioreactors
Denitrification
Ethanol
Nitrification*
Nitrogen
Phosphorus*
Sewage
Waste Disposal, Fluid

Substances

Acetates
Sewage
Phosphorus
Ethanol
Nitrogen