Multi-faceted effects and mechanisms of granular activated carbon to enhance anaerobic ammonium oxidation (anammox) for nitrogen removal from wastewater

Zhufang Wang; Chunxia Jiang; Mac-Anthony Nnorom; Claudio Avignone-Rossa; Kai Yang; Bing Guo

doi:10.1016/j.biortech.2024.132001

Multi-faceted effects and mechanisms of granular activated carbon to enhance anaerobic ammonium oxidation (anammox) for nitrogen removal from wastewater

Bioresour Technol. 2024 Dec 18:418:132001. doi: 10.1016/j.biortech.2024.132001. Online ahead of print.

Authors

Zhufang Wang¹, Chunxia Jiang², Mac-Anthony Nnorom¹, Claudio Avignone-Rossa³, Kai Yang⁴, Bing Guo⁵

Affiliations

¹ Centre for Environmental Health and Engineering (CEHE), Department of Civil and Environmental Engineering, University of Surrey, Guildford GU2 7XH, UK.
² Centre for Environmental Health and Engineering (CEHE), Department of Civil and Environmental Engineering, University of Surrey, Guildford GU2 7XH, UK; Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China.
³ Department of Microbial Sciences, University of Surrey, Guildford GU2 7XH, UK.
⁴ Advanced Technology Institute, University of Surrey, Guildford GU2 7XH, UK.
⁵ Centre for Environmental Health and Engineering (CEHE), Department of Civil and Environmental Engineering, University of Surrey, Guildford GU2 7XH, UK. Electronic address: b.guo@surrey.ac.uk.

PMID: 39706308
DOI: 10.1016/j.biortech.2024.132001

Abstract

Nitrogen removal via anammox is efficient but challenged by their slow growth. Adding granular activated carbon (GAC) increased the total nitrogen removal rate to 66.99 g-N/m³/day, compared to 50.00 g-N/m³/day in non-GAC reactor. Both reactors dominated by Candidatus Brocadia (non-GAC: 36.25 %, GAC: 35.5 %) but GAC improved specific anammox activity. Functional metabolic profiling from metagenomic analysis unveiled that GAC enhanced pathways associated with electron shuttle production, potentially promoting intra/extracellular electron transfer. In nitrogen metabolism, GAC is indicated to facilitate anammox N₂H₄ synthesis process, and inhibit nitrification and full denitrification processes, functioned by Nitrosomonas and Castellaniella which are more abundant in the non-GAC reactor. GAC also enhanced dissimilatory nitrate reduction to ammonium and partial denitrification processes, providing anammox with NH₄⁺/NO, which was conducted by Anaerolineae members (29.7 % in GAC-reactor and 7.8 % in non-GAC reactor sludge). This research illuminated the intricate microbial nitrogen cycling networks affected by GAC in anammox systems.

Keywords: Anammox; Functional genes; Granular activated carbon; Microbial metabolism; Nitrogen-cycling network.