We examined how long-term operation of anaerobic-oxic and anaerobic-anoxic sequencing batch reactors (SBRs) affects the enhanced biological phosphorus removal (EBPR) performance and sludge characteristics. The microbial characteristics of phosphorus accumulating organism (PAO) and denitrifying PAO (DPAO) sludge were also analyzed through a quantitative analysis of microbial community structure. Compared with the initial stage of operation characterized by unstable EBPR, both PAO and DPAO SBR produced a stable EBPR performance after about 100-day operation. From day 200 days (DPAO SBR) and 250 days (PAO SBR) onward, sludge granulation was observed, and the average granule size of DPAO SBR was approximately 5 times larger than that of PAO SBR. The DPAO granular sludge contained mainly rod-type microbes, whereas the PAO granular sludge contained coccus-type microbes. Fluorescence in situ hybridization analysis revealed that a high ratio of Accumulibacter clade I was found only in DPAO SBR, revealing the important role of this organism in the denitrifying EBPR system. A pyrosequencing analysis showed that Accumulibacter phosphatis was present in PAO sludge at a high proportion of 6%, whereas it rarely observed in DPAO sludge. Dechloromonas was observed in both PAO sludge (3.3%) and DPAO sludge (3.2%), confirming that this organism can use both O and NO as electron acceptors. Further, Thauera spp. was identified to have a new possibility as denitrifier capable of phosphorous uptake under anoxic condition.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.jes.2018.06.003 | DOI Listing |
Bioresour Technol
April 2024
School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China. Electronic address:
This work aims at intensifying the simultaneous removal of nitrogen and phosphorus of an integrated aerobic granular sludge (AGS) - membrane bioreactor (MBR) by Acinetobacter junii. After acclimation and enrichment in a sequencing batch reactor (SBR), Acinetobacter junii, a kind of denitrifying phosphate accumulating organism (DPAO), was successfully screened in the used SBR. Then it was verified to be capable of effectively enhancing the performance in the simultaneous removal of nitrogen and phosphorus of AGS-MBR.
View Article and Find Full Text PDFHuan Jing Ke Xue
September 2021
Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing 100124, China.
Actual domestic sewage has a complex composition and relatively low carbon and nitrogen content. Anaerobic plug-flow influent can enhance the utilization of COD by aerobic granular sludge by providing a locally high concentration of substrate. In this study, intermittent aeration was used to cultivate aerobic granular sludge in a sequencing batch reactor (SBR), and actual domestic sewage was used as the feed water to inoculate the sewage plant sludge.
View Article and Find Full Text PDFSci Total Environ
November 2021
Institute of Chemistry, University of Tartu, 14a Ravila St., 50411 Tartu, Estonia.
Lowered air supply and organic carbon need are the key factors to reduce wastewater treatment costs and thereby, avoid eutrophication. Denitrifying PO- removal (DPR) process using nitrate instead of oxygen for PO uptake was started up in the sequencing batch reactor (SBR) at a nitrate dosing rate of 20-25 mg N L d. Operation with a real municipal wastewater supplied with CHCOONa, KHPO and KNO succeeded in the cultivation of biomass containing denitrifying polyphosphate accumulating organisms (DPAOs).
View Article and Find Full Text PDFHuan Jing Ke Xue
February 2020
Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China.
To initiate the domestic sewage aerobic granular sludge (AGS) process, the experiment is operated by intermittent influent-effluent aeration to reduce the concentration of nitrate and the inhibition of PAO, and realize granulation by phosphate precipitation and positive electricity particles generated during phosphorus removal. The sludge from a sewage treatment plant is inoculated into the SBR reactors R1, R2, R3, and R4, for durations of 30, 60, 90, and 120 min total anaerobic time. This was used to study the effect of anaerobic time on the aerobic granular sludge system in domestic sewage.
View Article and Find Full Text PDFHuan Jing Ke Xue
March 2020
Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, College of Architecture and Civil Engineering, Beijing University of Technology, Beijing 100124, China.
SBR reactors R1 and R2 were used to inoculate activated sludge from a sewage treatment plant, and domestic sewage was used as the influent. The operation was carried out using a single and multiple influent-aeration operation strategy, respectively, and the particle size change and removal effect during the operation was studied. The results show that R1 and R2 successfully achieved sludge granulation after 56 days and 39 days of operation, respectively.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!