Long-term formation of microbial products in a sequencing batch reactor

Ni, Bing-Jie, Rittmann, Bruce E., Fang, Fang, Xu, Juan and Yu, Han-Qing (2010) Long-term formation of microbial products in a sequencing batch reactor. Water Research, 44 13: 3787-3796. doi:10.1016/j.watres.2010.04.035

Author Ni, Bing-Jie
Rittmann, Bruce E.
Fang, Fang
Xu, Juan
Yu, Han-Qing
Title Long-term formation of microbial products in a sequencing batch reactor
Journal name Water Research   Check publisher's open access policy
ISSN 0043-1354
Publication date 2010-07-01
Sub-type Article (original research)
DOI 10.1016/j.watres.2010.04.035
Open Access Status Not Open Access
Volume 44
Issue 13
Start page 3787
End page 3796
Total pages 10
Place of publication London United Kingdom
Publisher I W A Publishing
Language eng
Formatted abstract
Activated sludge in a sequencing batch reactor (SBR) is subjected to alternating feast-and-famine conditions, which may result in the enhanced production of microbial products: extracellular polymeric substances (EPS), soluble microbial products (SMP), and internal storage products (XSTO). In this work, the long-term formation of these three microbial products by activated sludge in an SBR is investigated using an expanded unified model with a parallel experimental study. We also use the model to compare the impacts in an SBR to those in a continuous-flow activated sludge system. The model captures all experimental trends for all components with solids retention time (SRT) for global steady state and within a cycle. At an SRT of 20 days, the active microorganisms constitute about 28% of the mixed liquor volatile suspended solids (MLVSS); the remaining biomass is comprised of residual inert biomass (XI) of 40%, EPS of 31%, and XSTO of ∼1%. The active biomass becomes a smaller fraction with the increasing SRT, while the inert biomass becomes increasingly dominant. For soluble components, effluent chemical oxygen demand (COD) is dominated by SMP, which varies to some degree in a cycle, peaking as external substrate becomes depleted. Within the SBR cycle, external substrate (S) declines strongly in the first part of the cycle, and SMP shows a small peak at the time of S depletion. XSTO is the only biomass component that varies significantly during the cycle. It peaks at the time that the input substrate (S) is depleted. Simulation for a continuous-flow activated sludge system and comparison with an SBR reveals that the constant " famine" conditions of the continuous system lead to lower EPS and XSTO, but higher MLVSS and XI.
Keyword Activated sludge
Extracellular polymeric substances (EPS)
Internal storage products (X(STO))
Sequencing batch reactor (SBR)
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Non-UQ

Document type: Journal Article
Sub-type: Article (original research)
Collection: Advanced Water Management Centre Publications
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Citation counts: TR Web of Science Citation Count  Cited 24 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 25 times in Scopus Article | Citations
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