Improving total nitrogen removal in aeration basin retrofitted with entrapped biomass.
This study presented a method to upgrade existing aeration tanks to remove total nitrogen (TN). Bioplates carrying entrapped biomass were installed in an aeration basin to create anoxic/anaerobic zones where denitrification can proceed. In a reactor that coupled bioplates containing entrapped biomass (equivalent to as high as 7,500 mg/L of biomass) and an activated sludge suspension (at mixed liquor suspended solids of 1,300-2,400 mg/L), nitrification efficiency exceeded 95% for an influent wastewater containing 21-54 mg/L of NH3-N. In all cases amended with alkalinity and with or without added methanol as an electron source, TN removal was between 60 and 70%. The results demonstrated anoxic/oxic or anaerobic/anoxic/oxic processes could be incorporated in a conventional aeration basin, requiring no substantial modifications of the vessel and operation, and thus providing improved treatment in terms of nitrogen removal in the conventional suspended-growth process.
Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Rd. Taipei 106, Taiwan E-mail cflin@ntu.edu.tw.
Yeong-Nan
YN
Chao
Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Rd. Taipei 106, Taiwan E-mail cflin@ntu.edu.tw.
Jui-Hsien
JH
Lin
Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Rd. Taipei 106, Taiwan E-mail cflin@ntu.edu.tw.
Kok-Kwang
KK
Ng
Department of Chemical and Materials Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung 807, Taiwan.
Chung-Hsin
CH
Wu
Department of Civil and Environmental Engineering, University of Utah, UT 84112, USA.
Pui-Kwan Andy
PK
Hong
Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Rd. Taipei 106, Taiwan E-mail cflin@ntu.edu.tw.
Cheng-Fang
CF
Lin
D018533:Biomass; D019149:Bioreactors; D058440:Denitrification; D058465:Nitrification; D009584:Nitrogen / Q000302:isolation & purification*; D018508:Water Purification / Q000295:instrumentation*
D009584:Nitrogen