Granular activated carbon (GAC)-driven microbial electron shuttle boosts denitrification and mitigates N₂O in cold and carbon-limited biofilm system.

ABSTRACT:

Background

Denitrification in wastewater treatment is severely limited under low-temperature and low-carbon ("dual-low") conditions, hindering sustainable nitrogen removal. Biofilm systems, though energy-efficient, suffer from reduced efficiency in such environments due to impaired interspecies electron transfer (IET). Granular activated carbon (GAC), a conductive mediator, offers potential to enhance IET between electroactive microorganisms (EAMs) and denitrifiers, yet its role in dual-low systems remains underexplored. This study investigates GAC's capacity to optimize biofilm functionality and mitigate greenhouse gas (GHG) emissions under these constraints.

Results

Under dual-low conditions (4-6°C, C/N = 4), GAC increased denitrification efficiency by 19.4-21.9% and reduc

SUBMITTER: Yang X 

PROVIDER: S-EPMC12315362 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature