کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
685345 889038 2009 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Long-term effect of dissolved oxygen on partial nitrification performance and microbial community structure
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی تکنولوژی و شیمی فرآیندی
پیش نمایش صفحه اول مقاله
Long-term effect of dissolved oxygen on partial nitrification performance and microbial community structure
چکیده انگلیسی

In this study, the performance of partial nitrification via nitrite and microbial community structure were investigated and compared in two sequencing batch reactors (SBR) with different dissolved oxygen (DO) levels. Both reactors achieved stable partial nitrification with nitrite accumulation ratio of above 95% by using real-time aeration duration control. Compared with high DO (above 3 mg/l on average) SBR, simultaneous nitrification and denitrification (SND) via nitrite was carried out in low DO (0.4–0.8 mg/l) SBR. The average efficiencies of SND in high DO and low DO reactor were 7.7% and 44.9%, and the specific SND rates were 0.20 and 0.83 mg N/(mg MLSS h), respectively. Low DO did not produce sludge with poorer settling properties but attained lower turbidities of the effluent than high DO. Fluorescence in situ hybridization (FISH) analysis in both the reactors showed that ammonia-oxidizing bacteria (AOB) were the dominant nitrifying bacteria and nitrite-oxidizing bacteria (NOB) did not be recovered in spite of exposing nitrifying sludge to high DO. The morphology of the sludge from both two reactors according to scanning electron microscope indicated that small rod-shaped and spherical clusters were dominant, although filamentous bacteria and few long rod-shaped coexisted in the low DO reactor. By selecting properly DO level and adopting process control method is not only of benefit to the achievement of novel biological nitrogen removal technology, but also favorable to sludge population optimization.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Bioresource Technology - Volume 100, Issue 11, June 2009, Pages 2796–2802
نویسندگان
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