National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
Bioresour Technol. 2019 Apr;278:435-439. doi: 10.1016/j.biortech.2019.02.004. Epub 2019 Feb 2.
Partial nitrification is crucial for application of autotrophic nitrogen removal which is beneficial for treating carbon-limited wastewater. This study presents an alternative strategy for achieving partial nitrification of domestic wastewater treatment, by treating activated sludge of a nitrifying reactor on long-term nitrite exposure. Initially, the nitrifying reactor obtained complete nitrification. After the sludge of the reactor was treated with nitrite at concentration of 5-30 mg·L without feeding for 32 days, the nitrite accumulation ratio (NAR) above 90% was achieved in 30 days, and then the NAR stabled at 97.9% under low temperature of 16.6 °C. Further analysis showed that the activity decay rate of ammonium-oxidizing bacteria (AOB) (0.020 d) was lower than that of nitrite-oxidizing bacteria (NOB) (0.035 d) under nitrite stress. Meanwhile, the NOB were effectively suppressed while AOB were dominant. These observations supported the feasibility of achieving stable partial nitrification by treating sludge on long-term exposure to nitrite.
短程硝化对于自养脱氮的应用至关重要，有利于处理碳受限废水。本研究提出了一种实现生活污水处理短程硝化的替代策略，即在长期亚硝酸盐暴露下处理硝化反应器中的活性污泥。最初，硝化反应器实现了完全硝化。在反应器的污泥在没有进水的情况下用 5-30mg·L 的亚硝酸盐处理 32 天后，在 30 天内实现了超过 90%的亚硝酸盐积累比（NAR），然后在 16.6°C 的低温下 NAR 稳定在 97.9%。进一步的分析表明，在亚硝酸盐胁迫下，氨氧化菌（AOB）（0.020 d）的活性衰减率低于亚硝酸氧化菌（NOB）（0.035 d）。同时，有效抑制了 NOB，而 AOB 占优势。这些观察结果支持了通过长期暴露于亚硝酸盐处理污泥来实现稳定短程硝化的可行性。
