Exploring the effects of intermittent aeration on the performance of nitrifying membrane-aerated biofilm reactors

Tal Elad*, Maria Philipsen Hally, Carlos Domingo-Félez, Oliver Knoop, Jörg E. Drewes, Borja Valverde-Pérez, Barth F. Smets

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

38 Downloads (Pure)

Abstract

Membrane-aerated biofilm reactors (MABRs) are an emerging technology for nutrient removal; however, a trade-off remains between their removal rate and oxygen transfer efficiency. This study compares nitrifying flow-through MABRs operated under continuous and intermittent aeration modes at mainstream wastewater ammonia levels. The intermittently-aerated MABRs maintained maximal nitrification rates, including under conditions allowing the oxygen partial pressure on the gas side of the membrane to considerably drop during the no-aeration period. Nitrous oxide emissions of all reactors were comparable and amounted to approximately 20 % of the converted ammonia. Intermittent aeration increased the transformation rate constant of atenolol, yet did not affect the removal of sulfamethoxazole. Seven additional trace organic chemicals were not biodegraded by any of the reactors. The ammonia-oxidizing bacteria in the intermittently-aerated MABRs were dominated by Nitrosospira, previously shown to be abundant at low oxygen concentrations and provide reactor stability under changing conditions. Our findings indicate that intermittently-aerated flow-through MABRs can achieve high nitrification rates and oxygen transfer efficiencies, highlighting the possible implications of air supply discontinuity on nitrous oxide emissions and trace organic chemical biotransformation.
Original languageEnglish
Article number164329
JournalScience of the Total Environment
Volume891
Number of pages8
ISSN0048-9697
DOIs
Publication statusPublished - 2023

Bibliographical note

The research leading to these results has received funding from the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement no. 754462 (EuroTechPostdoc) and has additionally been supported by the Novo Nordisk Foundation under grant number NNF21OC0071581 (VIRTUE) and the Danish Environmental Protection Agency’s MUDP (Project ‘Det non-biologiske minirenseanlæg’ 2020 – 15527).

Keywords

  • Nitrification
  • Oxygen transfer efficiency
  • Oxygen partial pressure
  • Nitrous oxide
  • Trace organic chemicals
  • Biotransformation

Fingerprint

Dive into the research topics of 'Exploring the effects of intermittent aeration on the performance of nitrifying membrane-aerated biofilm reactors'. Together they form a unique fingerprint.

Cite this