Immobilized biomass technology has been regarded as an effective strategy to enhance simultaneous nitrification and denitrification (SND) in existing aerobic biological wastewater treatment processes. Nevertheless, the mechanisms of SND in an aerobic immobilized biomass need to be proven. In this study, waste sludge from municipal wastewater treatment plants was immobilized by cellulose triacetate as bioplates, and an immobilized bioplate reactor (IBPR) was successfully established for nitrogen removal tests. The SND efficiency of the IBPR was increased 18% under the intermittent aeration (IA) mode compared with that under the continuous aeration (CA) mode. During IA operation, the IBPR achieved 96% COD removal and 76% NH₄⁺-N removal, with 71% SND. The results of microbial community analysis by high-throughput sequencing showed that nitrogen-related functional bacteria were more abundant in the bioplates than in the attached biofilms. The colocalization of nitrifiers and denitrifiers in the bioplates was observed, and the microbial community of nitrogen-related functional bacteria clearly shifted with the substrate concentration gradients.

固定化生物质技术被认为是提高现有好氧生物废水处理过程中同时硝化和反硝化（SND）的有效策略。然而，需要证明好氧固定生物质中 SND 的机制。本研究以三乙酸纤维素为生物板固定城市污水处理厂的废污泥，并成功建立了固定化生物板反应器（IBPR）进行脱氮试验。与连续曝气（CA）模式相比，间歇曝气（IA）模式下IBPR的SND效率提高了18%。在 IA 运行期间，IBPR 实现了 96% 的 COD 去除率和 76% 的 NH ₄ ⁺-N 去除，具有 71% SND。通过高通量测序的微生物群落分析结果表明，与氮相关的功能细菌在生物板中比在附着的生物膜中更丰富。观察到生物板中硝化菌和反硝化菌的共定位，并且与氮相关的功能细菌的微生物群落随着底物浓度梯度而明显变化。