Wang Huoqing, Sun Yuepeng, Wu Guangxue, Guan Yuntao
a Guangdong Province Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen , Tsinghua University , Shenzhen , People's Republic of China.
Environ Technol. 2019 May;40(13):1676-1685. doi: 10.1080/09593330.2018.1427801. Epub 2018 Jan 31.
Characteristics of nitrogen removal and nitrous oxide (NO) emission in the multiple anoxic/aerobic (AO) process were examined in three sequencing batch reactors (SBRs) with different anoxic durations (50 min, SBR; 40 min, SBR; 30 min, SBR) and a fixed aerobic duration of 30 min. The highest total inorganic nitrogen removal percentage of 85.8% was obtained in SBR, while a minimum NO emission factor of 1.9% was obtained in SBR. During nitrification batch experiments, the NO emission factor and emission rate were both lower in SBR than SBR. More NO production was obtained during denitrification in SBR when denitrifiers utilized intracellular organic carbon. Nitrite reduction by heterotrophs was the main NO production pathway during simultaneous nitrification and denitrification in SBR and SBR, with the NO emission factor of 31.3% and 36.3%, respectively. Adequate anoxic duration and lowering aerobic nitrite concentrations could be adopted to mitigate NO emission in the multiple AO process. The dominant microorganisms at the phylum level in all reactors were Proteobacteria and Bacteroidetes, while the abundance of Nitrospira was the highest in SBR with relatively lowest dissolved oxygen concentrations.
在三个序批式反应器（SBR）中研究了多段缺氧/好氧（AO）工艺中氮去除和一氧化二氮（N₂O）排放的特性，这三个反应器的缺氧时间不同（50分钟，SBR₁；40分钟，SBR₂；30分钟，SBR₃），好氧时间固定为30分钟。SBR₁中获得了最高的总无机氮去除率，为85.8%，而SBR₂中获得了最低的N₂O排放因子，为1.9%。在硝化批次实验中，SBR₁中的N₂O排放因子和排放速率均低于SBR₂。当反硝化菌利用细胞内有机碳时，SBR₃反硝化过程中产生的N₂O更多。在SBR₁和SBR₂的同步硝化反硝化过程中，异养菌还原亚硝酸盐是主要的N₂O产生途径，N₂O排放因子分别为31.3%和36.3%。在多段AO工艺中，可以采用适当的缺氧时间和降低好氧亚硝酸盐浓度来减少N₂O排放。所有反应器中门水平上的优势微生物为变形菌门和拟杆菌门，而在溶解氧浓度相对较低的SBR₁中，硝化螺旋菌属的丰度最高。
