| Title: |
Evaluation of the process performance of comammox-like nitrospira dominant down-flow hanging sponge reactor with reduced nitrous oxide emissions |
| Authors: |
Kabasawa, S.; Watari, T.; Sato, Y.; Hirakata, Y.; Hatamoto, M.; Okubo, T.; Vazquez, C. L.; Lier, J. B.; Yamaguchi, T. |
| Source: |
Water Research X ; 28 |
| Publisher Information: |
Elsevier; |
| Publication Year: |
2025 |
| Collection: |
UNESCO-IHE Institute for Water Education: Water Management Publications |
| Subject Terms: |
nitrous oxide; nitrification; wastewater treatment |
| Description: |
Nitrification/denitrification mitigates excess nitrogen in wastewater and reduces nutrient pollution in recipient surface waters but emits substantial amounts of nitrous oxide (N₂O). Complete ammonia-oxidizing (comammox) bacteria provide novel opportunities to mitigate N₂O emissions from wastewater treatment systems. In this study, a down-flow hanging sponge (DHS) reactor with low-strength ammonia-based synthetic wastewater was used to culture comammox bacteria, to study the microbial community structure, and to assess the nitrogen removal performance. The results showed a high NH4+-N removal efficiency of 98 ± 4 % and complete nitrification during the entire experimental period. 16S rRNA gene sequencing and metagenomic analysis showed that comammox-like Nitrospira dominated the DHS-retained sludge, and that comammox-like Nitrospira and ammonia-oxidizing archaea may have coexisted symbiotically. The dissolved N₂O emissions per NH4+-N removed from the DHS reactor were much lower than those from conventional activated sludge processes, indicating that the DHS reactor could be effective in reducing N₂O emissions during wastewater treatment. |
| Document Type: |
article in journal/newspaper |
| Language: |
unknown |
| Relation: |
https://doi.org/10.1016/j.wroa.2025.100324; http://cdm21063.contentdm.oclc.org/cdm/ref/collection/p21063coll3/id/24122 |
| DOI: |
10.1016/j.wroa.2025.100324 |
| Availability: |
https://doi.org/10.1016/j.wroa.2025.100324; http://cdm21063.contentdm.oclc.org/cdm/ref/collection/p21063coll3/id/24122 |
| Rights: |
CC BY-NC-ND 4.0 https://creativecommons.org/licenses/by-nc-nd/4.0/ |
| Accession Number: |
edsbas.5EECC2E2 |
| Database: |
BASE |