School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
Water Sci Technol. 2009;60(12):3243-51. doi: 10.2166/wst.2009.619.
Nitrogen removal via the nitrite pathway has the potential of reducing the requirements for aeration consumption and carbon source. However, the development of an efficient and quick start-up strategy for partial nitrification to nitrite has proven difficult in the treatment of low strength wastewater. In this study, the feasibility of partial nitrification achieved by using real-time aeration duration control was not only demonstrated from the kinetic mechanism, but also was validated in three sequencing batch reactors (SBRs) fed with low C/N domestic wastewater. Nitrite accumulation could be achieved when aeration was terminated as soon as an inflexion pH point was reached (the dpH/dt became from negative to positive). The reduction or limitation of the NOB growth could be achieved through aeration duration control, due to leaving no extra time for NOB to convert the accumulated nitrite. The experimental operation results also showed that partial nitrification with nitrite accumulation ratios of over 80% was achieved successfully in these three reactors with process control. Fluorescence in situ hybridization (FISH) analysis indicated the reduction of NOB was achieved and AOB became the dominant nitrifying bacteria. Moreover, an integrated start-up strategy based on aeration duration control was proposed to quickly achieve partial nitrification to nitrite.
通过亚硝酸盐途径进行脱氮具有降低需氧量和碳源需求的潜力。然而，在处理低浓度废水时，证明开发高效、快速的亚硝化启动策略具有一定难度。在本研究中，通过实时曝气时间控制实现亚硝化的可行性不仅从动力学机制上得到了证明，而且在三个序批式反应器（SBR）中用低 C/N 生活污水进行了验证。当达到拐点 pH 值（dpH/dt 由负变正）时，停止曝气即可实现亚硝酸盐积累。通过曝气时间控制可以减少或限制 NOB 的生长，因为没有多余的时间让 NOB 将积累的亚硝酸盐转化。实验运行结果还表明，通过过程控制，这三个反应器中成功实现了亚硝酸盐积累比超过 80%的部分硝化。荧光原位杂交（FISH）分析表明，NOB 被减少，AOB 成为优势硝化菌。此外，提出了一种基于曝气时间控制的综合启动策略，可快速实现亚硝化至亚硝酸盐。
