溶解氧分区控制的一段式自养脱氮工艺的性能及其中微生物的特征

针对一段式自养脱氮工艺普遍存在脱氮性能较差或不稳定的问题，提出了溶解氧分区控制的策略，研发了一种内外分层、溶解氧分区的新型自养脱氮反应器。通过改变反应器的进水氮负荷和调控曝气量，考察其溶解氧分区效果和脱氮性能变化，并探究长期运行过程中微生物群落结构特征。结果表明：在为期250 d的连续实验中，新型反应器能实现良好的溶解氧分区效果，可有效强化氨氧化速率和厌氧氨氧化速率，总氮去除率到达84.3%，氮去除速率为0.84 kg·(m³·d) ⁻¹，自养脱氮性能得到了提升；反应器中微生物群落结构趋向单一，浮霉菌门始终维持较高丰度（7.6%~10.5%），厌氧氨氧化菌的优势菌属则发生了由Candidatus Kuenenia向Candidatus Brocadia的演替，而亚硝酸盐氧化菌生长受到抑制。本研究结果可为自养脱氮工艺的应用提供参考。

Performance and microbial characteristic of one stage autotrophic denitrification process controlled by dissolved oxygen zone

In order to solve the problem of poor or unstable denitrification performance in one-stage autotrophic denitrification process, the strategy of zonal control of dissolved oxygen was proposed and a novel autotrophic nitrogen removal bioreactor with internal and external layers and dissolved oxygen partitions was developed. By changing the influent nitrogen load and regulating aeration, the effect of the dissolved oxygen partition and the change of nitrogen removal performance were investigated, the microbial characteristics during long-term operation were also explored. The results showed that the novel reator could achieve good partition effect of dissolved oxygen and enhanced the rates of ammonia oxidation and anammox during the continuous operation of 250 days. The total nitrogen removal efficiency reached 84.3%, and the nitrogen removal rate was 0.84 kg·(m3·d) -1. The autotrophic nitrogen removal performance was improved. The microbial community tended to be simple and the abundance of Planctomycetes was at a high level (7.6%~10.5%). The dominant bacteria of anaerobic ammonium oxidation bacteria gradually transformed from Candidatus Kuenenia to Candidatus Brocadia, while the growth of nitrite oxidizing bacteria was inhibited. The results of this study could provided technical support for the application of autotrophic denitrification process.