Long-term effect of dissolved oxygen on partial nitrification performance and microbial community structure
Long-term effect of dissolved oxygen on partial nitrification performance and microbial community structure
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溶解氧对部分硝化性能和微生物群落结构的长期影响
DOI：
10.1016/j.biortech.2008.12.036
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发表时间：
2009-06-01
影响因子：
11.4
通讯作者：
Wang, Zhongwei
中科院分区：
文献类型：
--
作者：
Guo, Jianhua;Peng, Yongzhen;Wang, Zhongwei
在两种不同溶解氧水平的序批式反应器(SBR)中，考察和比较了亚硝酸盐部分硝化作用的性能和微生物群落结构。两种反应器均采用实时曝气时间控制，实现了稳定的部分硝化，亚硝酸盐积累率达95%以上。与高DO(平均大于3 mg/L)SBR相比，低DO(0.4~0.8 mg/L)SBR可同时进行亚硝酸盐硝化反硝化。高DO和低DO反应器的平均SND效率分别为7.7%和44.9%，比SND速率分别为0.20和0.83 mg N/(Mg MLSS H)。低DO不会产生沉降性能较差的污泥，但出水浊度低于高DO。两种反应器中的荧光原位杂交(FISH)分析表明，氨氧化细菌(AOB)是硝化细菌的优势菌，亚硝酸氧化细菌(NOB)在硝化污泥暴露于高DO的情况下仍未恢复。扫描电子显微镜观察表明，两种反应器的污泥形态均以小棒状和球状为主，但在低DO反应器中丝状菌和少量长棒状并存。选择合适的DO水平和采用工艺控制方法，不仅有利于新型生物脱氮技术的实现，而且有利于污泥种群的优化。皇冠版权所有(C)2009由爱思唯尔有限公司出版。保留所有权利。
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. Crown Copyright (c) 2009 Published by Elsevier Ltd. All rights reserved.