In:
Environmental Science: Water Research & Technology, Royal Society of Chemistry (RSC), Vol. 8, No. 9 ( 2022), p. 1845-1858
Abstract:
In this study, the microbial community contributing to nitrogen-transforming processes was investigated in a rotating biological contactor (RBC) system treating wastewater from a fresh market building. Insights into core nitrogen-transforming microorganisms in the RBC biofilms were explored through a quantitative PCR approach and high-throughput sequencing of 16S rRNA and the nitrogen functional genes ( e.g. , amoA , NxrB , NxrA , and narG ). A high abundance of autotrophic ammonia-oxidizing bacteria (AOB) and anaerobic ammonia oxidizing (anammox) bacteria ( Candidatus Brocadia and Candidatus Anammoximicrobium) was detected in the RBC biofilms, suggesting their roles in aerobic and anaerobic ammonia oxidation, respectively. Heterotrophic AOB, ammonia-oxidizing archaea (AOA), and complete ammonia oxidation (comammox) bacteria were detected at relatively low abundance. High numbers of Nitrospira suggested that nitrite oxidation was also a crucial nitrogen-transforming pathway in these RBC biofilms. Together with common denitrifying bacteria, partial denitrifiers ( Thiobacillus , Thauera , Terrimonas , and Flavobacterium ) were also detected in the biofilms. Our data reveal the co-occurrence of nitrogen-transforming microorganisms with broad ranges of substrate affinities, which likely accounts for the performance and stability of the RBC system. Based on the nitrogen-transforming microorganisms identified here, it is proposed that partial nitrification/anammox, nitrification/partial denitrification/anammox, or both pathways are crucial for nitrogen-removal in RBC biofilms (besides the conventional nitrification–denitrification). Thus, RBCs might be useful for promoting ‘shortcut’ nitrogen removal as an energy-efficient system for treating medium-strength wastewater.
Type of Medium:
Online Resource
ISSN:
2053-1400
,
2053-1419
Language:
English
Publisher:
Royal Society of Chemistry (RSC)
Publication Date:
2022
Permalink