Coupling of the Feammox - Anammox pathways by using a sequential discontinuous bioreactor

• Published in: Bioresource technology Vol. 395; p. 130334
• Main Authors: González, Macarena, Cerda, Ámbar, Rodríguez, Carolina, Serrano, Jennyfer, Leiva, Eduardo
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.03.2024
• Subjects: Anaerobic iron reduction; NH4+ removal; Nitrogen; Wastewater; NH4+ removal; Nitrogen; Wastewater; Anaerobic iron reduction; NH(+) removal
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2024.130334

[Display omitted] •Sodium acetate as carbon source allowed enrichment of Feammox microorganisms.•Innovative Feammox-Anammox synergy enhances NH4+ removal in SBR.•NH4+ removal of 50.8 % Feammox-Anammox coupling operation after 10 weeks.•Functional genes and Feammox-related bacteria were found in separate and coupled SBRs. Treating nitrogenous compounds in wastewater is a contemporary challenge, prompting novel approaches for ammonium (NH4+) conversion to molecular nitrogen (N2). This study explores the classic anaerobic ammonium oxidation process (Anammox) coupled to the iron-dependent anaerobic ammonium oxidation process (Feammox) in a sequential discontinuous bioreactor (SBR) for NH4+ removal. Feammox and Anammox cultures were individually enriched and combined, optimizing the coupling, and identifying key variables influencing the enrichment process. Adding sodium acetate as a carbon source significantly reduces Fe3+ to Fe2+, indicating Feammox activity. Both Anammox and Feammox processes were successfully operated in SBRs, achieving efficient NH4+ removal (Anammox: 64.6 %; Feammox: 43.4 %). Combining these pathways in a single SBR enhances the NH4+ removal capacity of 50.8 %, improving Feammox efficiency. The Feammox process coupled with Anammox may generate the nitrite (NO2–) needed for Anammox. This research contributes to biotechnological advancements for sustainable nitrogenous compound treatment in SBRs.