Water Environ Res. 2018 Jun 1;90(6):498-509. doi: 10.2175/106143017X14902968254818. Epub 2017 Jul 25.
The objective of this study was to investigate the effect of dissolved oxygen on nitrification in a sequencing batch reactor (SBR) treating low ammonia wastewater (40 mg N/L) at a low temperature (14 °C). During the 130 days of operation, three dissolved oxygen levels (5-6 mg dissolved oxygen/L, 2-3 mg dissolved oxygen/L, and 0.8-1.0 mg dissolved oxygen/L) were tested. Dissolved oxygen reduction resulted in lower ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) activity, with decreasing ammonia conversion ratio and increasing nitrite accumulation ratio. The maximum growth rates of AOB and NOB determined in this study (0.28 and 0.38 d-1) were below the median values from the literature (0.47 and 0.62 d-1), whereas the oxygen half-saturation coefficients of AOB and NOB (1.36 and 2.79 mg/L) were higher than those found in the literature. The kinetic model explained the SBR performance well. Low dissolved oxygen, together with long solids retention time, was recommended for partial nitrification at a low temperature.
本研究旨在探讨溶解氧对低氨废水（40mg N/L）在低温（14°C）下序批式反应器（SBR）硝化的影响。在 130 天的运行中，测试了三种溶解氧水平（5-6mg 溶解氧/L、2-3mg 溶解氧/L 和 0.8-1.0mg 溶解氧/L）。溶解氧的降低导致氨氧化细菌（AOB）和亚硝酸盐氧化细菌（NOB）活性降低，氨转化率降低，亚硝酸盐积累比增加。本研究中确定的 AOB 和 NOB 的最大生长速率（0.28 和 0.38 d-1）低于文献中的中位数（0.47 和 0.62 d-1），而 AOB 和 NOB 的氧半饱和系数（1.36 和 2.79mg/L）高于文献中的值。动力学模型很好地解释了 SBR 的性能。低温下，低溶解氧与长固体停留时间相结合，有利于部分硝化。
