[Enrichment of denitrifying phosphate accumulating organisms in sequencing batch membrane bioreactors].
The enrichment and characteristics of denitrifying phosphate accumulating organisms (DPAO), which are capable of utilizing nitrate as electron acceptor, was investigated in a laboratory-scale sequencing batch membrane bioreactors (SBMBR). The results demonstrated that the proportion of DPAO increased from 19.4% to 69.6% of total phosphate accumulating organisms after anaerobic-aerobic and anaerobic-anoxic-aerobic phases. SBMBR system could operate steadily when 120 mg nitrate was added continuously during the anoxic phase every period. Simultaneous phosphate uptake and biological denitrification with good performance could be obtained in SBMBR operated in steady-state. Nitrate and phosphorus removal efficiency were above 100% and 84% respectively during anoxic phase, however, the effluent TP concentration was low than 0.5 mg/L, the total phosphorus removal efficiency was 96.1%. Furthermore, the ammonium nitrogen removal efficiency of SBMBR could be maintained at 92.2%, and the cumulation of nitrite and nitrate was not observed clearly.
Dai
Wen-Chen
WC
School of Environmental and Biological Science and Technology, Dalian University of Technology, Dalian 116024, China. daiyi1636@sina.com
Zhang
Han-Min
HM
Xiao
Jing-Ni
JN
Yang
Feng-Lin
FL
Zhang
Xing-Wen
XW
Zhang
Xin-Yu
XY
D000693:Anaerobiosis; D001419:Bacteria / Q000254:growth & development / Q000378:metabolism*; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology*; D009566:Nitrates / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism; D010758:Phosphorus / Q000302:isolation & purification / Q000378:metabolism*; D014865:Waste Disposal, Fluid / Q000379:methods*; D014873:Water Pollutants / Q000302:isolation & purification / Q000378:metabolism*; D018508:Water Purification / Q000379:methods
D009566:Nitrates; D014873:Water Pollutants; D010758:Phosphorus; D009584:Nitrogen