Effects of acetate and nitrite addition on fraction of denitrifying phosphate-accumulating organisms and nutrient removal efficiency in anaerobic/aerobic/anoxic process

Koichi Soejima, Kazuma Oki, Akihiko Terada, Satoshi Tsuneda, Akira Hirata

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    16 Citations (Scopus)


    The effects of acetate and nitrite on the performance of sequencing batch reactors (SBRs) employing an anaerobic/aerobic/anoxic (AOA) process were investigated. Three types of SBR operations were used: sodium acetate addition at the start of anoxic condition for heterotrophic denitrification (Type 1); sodium acetate addition at the start of aerobic condition for anoxic phosphate removal by denitrifying phosphate-accumulating organisms (DNPAOs) (Type 2: conventional AOA process); and nitrite addition at the start of aerobic condition for inhibition of phosphate-accumulating organisms (PAOs) (Type 3). A track experiment shows that Type 2 led to the best performance of SBRs among the three types. An analysis by fluorescence in situ hybridization (FISH) revealed that nitrite addition decreased the ratio of PAOs with a decrease in phosphorus removal efficiency. The fraction of DNPAOs in Type 2 was the highest at 13%, indicating that Type 2 is suitable for the simultaneous nitrogen and phosphorus removal in the AOA process.

    Original languageEnglish
    Pages (from-to)305-313
    Number of pages9
    JournalBioprocess and Biosystems Engineering
    Issue number5-6
    Publication statusPublished - 2006 Dec



    • Anaerobic/aerobic/anoxic process (AOA process)
    • Denitrifying phosphate-accumulating organisms (DNPAOs)
    • Enhanced biological phosphorus removal (EBPR)
    • Glycogen-accumulating organisms (GAOs)
    • Sequencing batch reactor (SBR)

    ASJC Scopus subject areas

    • Chemical Engineering(all)
    • Applied Microbiology and Biotechnology
    • Biotechnology
    • Bioengineering
    • Environmental Science (miscellaneous)

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