Confronting Assumptions of Phosphorus-Accumulating Organisms and Glycogen-Accumulating Organisms: Peaceful Coexistence in a Carbon-Limited Sidestream EBPR Demonstration

McKenna Farmer, Fabrizio Sabba*, Zhen Jia, Patrick Dunlap, James Barnard, Cindy Dongqi Qin, Levi Straka, Joseph A. Kozak, Leon Downing, George Wells

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

4 Scopus citations

Abstract

Enhanced biological phosphorus removal (EBPR) is strongly influenced by the influent ratio of readily biodegradable carbon to soluble phosphorus due to the preferences of phosphorus-accumulating organisms (PAO). The sidestream EBPR (S2EBPR) process redirects a portion of return activated sludge (RAS) to a sidestream fermenter, increasing the availability of biodegradable carbon. In this study, we assessed the performance and microbial community structure of a full-scale S2EBPR demonstration supplemented with external carbon dosing. By the end of the 10 month study period, the demonstration achieved a median effluent orthophosphate of 0.3 mg/L. The microbial community consisted of a common core microbiome in the RAS fermenter, EBPR basin, and nitrification basin. The most abundant PAO detected were Ca. “Dechloromonas phosphorivorans”, while the canonical PAO Ca. “Accumulibacter” and Tetrasphaera were observed in lower relative abundance. In addition to non-canonical PAO enrichment, the glycogen-accumulating organism Ca. “Competibacter” proliferated throughout the study and at some points outnumbered PAO taxa by 30 to 1 with no tangible performance impacts. This study provides insights into successful S2EBPR implementation at a low-carbon facility and improves our understanding of microbial community structure and key PAO and GAO in S2EBPR systems.

Original languageEnglish (US)
Pages (from-to)2384-2394
Number of pages11
JournalACS ES and T Water
Volume3
Issue number8
DOIs
StatePublished - Aug 11 2023

Keywords

  • GAO
  • PAO
  • RAS fermentation
  • S2EBPR
  • phosphorus

ASJC Scopus subject areas

  • Chemistry (miscellaneous)
  • Chemical Engineering (miscellaneous)
  • Environmental Chemistry
  • Water Science and Technology

Fingerprint

Dive into the research topics of 'Confronting Assumptions of Phosphorus-Accumulating Organisms and Glycogen-Accumulating Organisms: Peaceful Coexistence in a Carbon-Limited Sidestream EBPR Demonstration'. Together they form a unique fingerprint.

Cite this