Low temperature environment was one of the difficulties in sewage treatment. In this study, the removal efficiency of multistage AO process was analysed under different hydraulic residence time (12 h, 8 h and 6 h) and inlet flow distribution ratio(5 : 4 : 4, 3 : 2 : 1 and 25 : 15 : 6), the rules of pollutant migration and transformation were compared and analysed under different control parameters. The results show that enhanced nitrogen removal and optimised organics utilisation were obtained simultaneously in the feeding process with hydraulic retention time of 8 h as well as influent distribution ratio of 3 : 2 : 1. HRT and inlet flow distribution ratio affect nitrogen load and organic matter distribution in each stage of the multistage AO system, the removal efficiency of ammonia nitrogen in each stage of the system was more than 80% under optimal conditions, the total nitrogen removal rate was more than 80%, among which the synchronous nitrification and denitrification account for 29.50%.

中文翻译：

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水力停留时间和入口流量分配比对多级AO工艺中低温城市污水污染物去除的影响

低温环境是污水处理的难点之一。在这项研究中，分析了在不同的水力停留时间（12 h，8 h和6 h）和入口流量分配比（5：4：4、3：2：1和25:15:15）下多级AO工艺的去除效率。 6）比较了不同控制参数下污染物的迁移转化规律。结果表明，在进料过程中，水力停留时间为8 h，进水分配比为3：2：1，同时提高了氮的去除率和优化了有机物的利用率。HRT和入口流量分配比影响氮负荷和有机物在多阶段AO系统的每个阶段进行分配，