Nitrous oxide emission in autotrophic partial nitritation system : Macro- and microanalyses

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Author(s)

    • Ju Kai Ju Kai
    • School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology
    • Wang Lei Wang Lei
    • School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology
    • Zhang Xueling
    • School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology
    • Miao Rui
    • School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology
    • Wang Xudong
    • School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology

Abstract

A laboratory-scale sequencing batch reactor fed with synthetic high-ammonium wastewater was operated for autotrophic partial nitritation, and the characteristics of N_2O emission were investigated by both macro- and microanalysis. A N_2O emission quantity of 5.98 ± 1.24 mg (n = 17) was observed, accounting for 0.997% ± 0.408% of the influent nitrogen. The N_2O level in the off-gas first increased to a maximum of 91.5 ppmv in the initial 50 min, and then decreased and remained around 34.8 ppmv until the end of aeration. An asymptotic function (y = 14.3-14.2 × 0.992^x, R^2 = 0.997) could be used to estimate the quantity of N_2O emitted. Microelectrodes were used to explore the variations in the nitrogen distribution and consumption rate within sludge flocs as the reaction proceeded. During the aeration phase, partial nitritation occurred mainly in the surface layer of flocs. This is where most N_2O was produced, indicating that N_2O was generated as a byproduct of the nitritation. During the settling phase, the N_2O concentration and volumetric production rate were much higher than those in the aeration phase, suggesting that the settling phase contributes to the initial N_2O emission peak.

Journal

  • Journal of bioscience and bioengineering

    Journal of bioscience and bioengineering 120(4), 419-425, 2015-10

    The Society for Biotechnology, Japan

Codes

  • NII Article ID (NAID)
    110010010224
  • NII NACSIS-CAT ID (NCID)
    AA11307678
  • Text Lang
    ENG
  • ISSN
    1389-1723
  • NDL Article ID
    026823870
  • NDL Call No.
    Z53-S65
  • Data Source
    NDL  NII-ELS 
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