Anammox granular sludge in low-ammonium sewage treatment: Not bigger size driving better performance. (1st October 2018)

• Record Type: Journal Article
• Authors: Zhu, Guibing; Wang, Shanyun; Ma, Bin; Wang, Xiaoxia; Zhou, Jiemin; Zhao, Siyan; Liu, Ruiping
• Is Part Of: Water research. Volume 142(2018)
• Page Start: 147
• Page End: 158
• Publication Date: 2018-10-01
• Subjects: Anammox -- Granular sludge size -- Low-ammonium sewage treatment -- Abundance -- Microbial mechanism -- N2O emission; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2018.05.048
• Languages: English
• ISSNs: 0043-1354

Abstract

Abstract: An integrated investigation to document high anammox abundance, activity and diversity in upflow anaerobic sludge blanket (UASB) reactor treating low-strength ammonium loading sewage was performed and showed that the optimal anammox granular sludge sizes could mitigate undesirable N2 O emission. The enhanced anammox bacterial abundance, activity and specific anammox rate were achieved with optimal granules sludge sizes of 0.5–0.9 mm with multiple " Jettenia ", " Brocadia ", and " Anammoxoglobus " species. The tightly-bound extracellular polymeric substance (TB-EPS) was the main EPS layer found in anammox granular sludge, in which polysaccharides play an important structural role. Over this granular sludge sizes, the anammox bacterial abundance and activity did not significantly decrease, but N2 O emission significantly increased. High throughput sequencing and ecological networks demonstrated the patterns of anammox and their co-occurring bacteria, with availability N2 O-producer and N2 O-reducer functional genes. Incomplete denitrification and insufficient carbon source mainly contributed to N2 O production in granular sludge, as supported by results of stratification analysis. Graphical abstract: Highlights: There is an optimal anammox granular sludge sizes in low-ammonium sewage treatment. These anammox granules have peaks in N-removal rate and anammox bacterial abundance. Over these sizes, the anammox bacterial abundance and activity do not significantly decrease. However, over these sizes, the N2 O emission greatly increases.