Ju Kai, Wang Lei, Lv Yongtao, Zhang Xueling, Miao Rui, Wang Xudong
School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13 Yanta Road, Xi'an 710055, China.
J Biosci Bioeng. 2015 Oct;120(4):419-25. doi: 10.1016/j.jbiosc.2015.02.005. Epub 2015 Mar 16.
A laboratory-scale sequencing batch reactor fed with synthetic high-ammonium wastewater was operated for autotrophic partial nitritation, and the characteristics of N2O emission were investigated by both macro- and microanalysis. A N2O emission quantity of 5.98 ± 1.24 mg (n = 17) was observed, accounting for 0.997% ± 0.408% of the influent nitrogen. The N2O 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 N2O 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 N2O was produced, indicating that N2O was generated as a byproduct of the nitritation. During the settling phase, the N2O concentration and volumetric production rate were much higher than those in the aeration phase, suggesting that the settling phase contributes to the initial N2O emission peak.
以合成高氨废水为进水的实验室规模序批式反应器用于自养型部分亚硝化，并通过宏观和微观分析研究了N2O排放特性。观察到N2O排放量为5.98±1.24毫克（n = 17），占进水氮的0.997%±0.408%。尾气中的N2O水平在最初50分钟内先升至最高91.5 ppmv，然后下降并在曝气结束前保持在34.8 ppmv左右。可用渐近函数（y = 14.3 - 14.2×0.992(x)，R(2) = 0.997）估算N2O排放量。使用微电极探索反应进行过程中污泥絮体内部氮分布和消耗速率的变化。在曝气阶段，部分亚硝化主要发生在絮体表层。这是产生大部分N2O的地方，表明N2O是亚硝化的副产物。在沉淀阶段，N2O浓度和体积产生速率远高于曝气阶段，表明沉淀阶段促成了初始N2O排放峰值。
