The aim of the present study was to evaluate the capability of an up-flow anammox sludge bed reactor (13 L) of dampening a 10 °C temperature drop at mainstream conditions while operating at constant nitrogen loading rates (0.11 ± 0.01 g N L⁻¹ d⁻¹). The up-flow anammox sludge bed reactor was fed with an aerobically pre-treated mainstream wastewater. The reactor temperature was controlled as to mimic a (realistic) summer-to-winter transition from 20 to 10 °C plus a three months period at 10 °C. During the 350 days of operation, the average nitrogen removal rate remained high (0.10 ± 0.01 g N L⁻¹ d⁻¹), indicating that the 10 °C drop did not affect the overall efficiency of the reactor. This can be explained as anammox activity differed among the different sludge bed sections. At 20 °C, anammox activity was mainly located at the bottom of the sludge bed. At 10 °C, the anammox activity decrease of the bottom sludge bed was compensated by an activity increase within the upper sludge bed sections. The contribution of heterotrophic denitrifying activity to the total nitrogen removal rate was assessed to be 3-to-5 times lower than that of anammox, even at 10 °C. Microbial community of 16S rRNA gene-targeted sequencing analyses resulted in the identification of an uncharacterized Planctomycetes in high numbers. This study demonstrated that the low temperatures should not be an obstacle for the feasibility of anammox bacteria in the main water line of an urban wastewater treatment plant.

本研究的目的是评估在主流氮气条件下，以恒定氮负荷率（0.11±0.01 g N L ^-1）运行时，上流式厌氧污泥床反应器（13 L）抑制10°C温度下降的能力。 d ^-1）。给上流的厌氧污泥床反应器供入需氧预处理的主流废水。控制反应器温度以模拟（现实的）从夏季到冬季的从20到10°C的过渡，再加上在10°C的三个月时间。在运行的350天中，平均氮去除率仍然很高（0.10±0.01 g NL ^-1 d ^-1），表明10°C的下降不会影响反应器的整体效率。这可以解释为不同污泥床段之间的厌氧氨氧化活性不同。在20°C时，厌氧氨氧化活性主要位于污泥床的底部。在10°C时，底部污泥床的厌氧氨氧化活性下降被上部污泥床段内的活性增加所补偿。甚至在10°C时，异养反硝化活性对总氮去除率的贡献也被估计比厌氧氨氧化要低3至5倍。微生物群落的16S rRNA基因靶向测序分析导致大量鉴定未鉴定的扁平菌。