The effect of dissolved oxygen concentration on long-term stability of partial nitrification process
The effect of dissolved oxygen concentration on long-term stability of partial nitrification process
复制标题
溶解氧浓度对部分硝化过程长期稳定性的影响
DOI：
10.1016/j.jes.2019.12.012
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发表时间：
2020-04-01
影响因子：
6.9
通讯作者：
Liu, Zhibin
中科院分区：
文献类型：
--
作者：
Cui, Bin;Yang, Qing;Liu, Zhibin
溶解氧浓度是影响短程硝化过程的关键因素之一。然而，实现和保持稳定的短程硝化在不同的溶解氧浓度被广泛报道。溶解氧浓度对短程硝化的影响机理尚不清楚。因此，在本研究中，建立了两个相同的序批式反应器（SBR）培养相同的接种污泥与实时控制策略。在SBR反应器中控制不同的DO浓度，探讨DO浓度对短程硝化工艺长期稳定性的影响。结果表明，当DO浓度从2.5 mg/L降至0.5 mg/L时，氨氮氧化速率（AOR）受到抑制。在190个运行周期中，硝化螺菌的丰度从10（11.5）拷贝/g DNA增加到10（13.7）拷贝/g DNA，相对百分比从0.056%增加到3.2%，使部分硝化过程逐渐转变为完全硝化过程。当溶解氧浓度为2.5mg/L时，硝化螺菌的丰度稳定，氨氧化细菌的丰度始终保持在10（10.7）拷贝/g DNA。保持了较高的AOR，保持了稳定的短程硝化过程。DO为2.5 mg/L时，氨氧化细菌（AOB）活性显著高于亚硝酸盐氧化细菌（NOB）活性，这对维持优良的亚硝酸盐积累性能至关重要。(C)2020中国科学院生态环境科学研究中心由爱思唯尔公司出版
Dissolved oxygen (DO) concentration is regarded as one of the crucial factors to influence partial nitrification process. However, achieving and keeping stable partial nitrification under different DO concentrations were widely reported. The mechanism of DO concentration influencing partial nitrification is still unclear. Therefore, in this study two same sequencing batch reactors (SBRs) cultivated same seeding sludge were built up with real-time control strategy. Different DO concentrations were controlled in SBRs to explore the effect of DO concentration on the long-term stability of partial nitrification process at room temperature. It was discovered that ammonium oxidation rate (AOR) was inhibited when DO concentration decreased from 2.5 to 0.5 mg/L. The abundance of Nitrospira increased from 10(11.5) to 10(13.7) copies/g DNA, and its relative percentage increased from 0.056% to 3.2% during 190 operational cycles, causing partial nitrification gradually turning into complete nitrification process. However, when DO was 2.5 mg/L the abundance of Nitrospira was stable and AOB was always kept at 10(10.7) copies/g DNA. High AOR was maintained, and stable partial nitrification process was kept. Ammonia oxidizing bacteria (AOB) activity was significantly higher than nitrite oxidizing bacteria (NOB) activity at DO of 2.5 mg/L, which was crucial to maintain excellent nitrite accumulation performance. (C) 2020 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.