The coexistence and competition of canonical and comammox nitrite oxidizing bacteria in a nitrifying activated sludge system - Experimental observations and simulation studies

Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved..

The second step of nitrification can be mediated by nitrite oxidizing bacteria (NOB), i.e. Nitrospira and Nitrobacter, with different characteristics in terms of the r/K theory. In this study, an activated sludge model was developed to account for competition between two groups of canonical NOB and comammox bacteria. Heterotrophic denitrification on soluble microbial products was also incorporated into the model. Four 5-week washout trials were carried out at dissolved oxygen-limited conditions for different temperatures (12 °C vs. 20 °C) and main substrates (NH4+-N vs. NO2--N). Due to the aggressive reduction of solids retention time (from 4 to 1 d), the biomass concentrations were continuously decreased and stabilized after two weeks at a level below 400 mg/L. The collected experimental data (N species, biomass concentrations, and microbiological analyses) were used for model calibration and validation. In addition to the standard predictions (N species and biomass), the newly developed model also accurately predicted two microbiological indicators, including the relative abundance of comammox bacteria as well as nitrifiers to heterotrophs ratio. Sankey diagrams revealed that the relative contributions of specific microbial groups to N conversion pathways were significantly shifted during the trial. The contribution of comammox did not exceed 5 % in the experiments with both NH4+-N and NO2--N substrates. This study contributes to a better understanding of the novel autotrophic N removal processes (e.g. deammonification) with nitrite as a central intermediate product.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:864

Enthalten in:

The Science of the total environment - 864(2023) vom: 15. März, Seite 161084

Sprache:

Englisch

Beteiligte Personen:

Mehrani, Mohamad-Javad [VerfasserIn]
Kowal, Przemyslaw [VerfasserIn]
Sobotka, Dominika [VerfasserIn]
Godzieba, Martyna [VerfasserIn]
Ciesielski, Slawomir [VerfasserIn]
Guo, Jianhua [VerfasserIn]
Makinia, Jacek [VerfasserIn]

Links:

Volltext

Themen:

7664-41-7
Ammonia
Comammox
Journal Article
Nitrites
Nitrobacter
Nitrogen Dioxide
Nitrospira
Process simulation
S7G510RUBH
Sewage
Two-step nitrification

Anmerkungen:

Date Completed 26.01.2023

Date Revised 01.02.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.scitotenv.2022.161084

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM350773866