不同SRT选择性排泥实现除磷亚硝化试验研究

常温条件下(20~25℃),采用序批式反应器(SBR)研究了2种排泥方式在3个不同梯度污泥龄(40、20、10 d)下生活污水的除磷亚硝化效果.结果表明:整个过程亚硝化率都在95%以上,随着污泥龄(SRT)的减小,系统除磷能力逐渐提高,氨氮去除容积负荷逐渐降低;在相同SRT条件下,排污泥床表层污泥比排底层污泥能获得更好的除磷效果和更高的氨氮去除容积负荷.在长期运行中发现,采用排污泥床表层污泥的方式,控制污泥龄为20 d,总磷去除率为95.92%~97.12%,出水总磷质量浓度为0.1~0.4 mg/L,氨氮去除容积负荷为0.12 kg/(m3·d),出水亚硝酸盐氮和氨氮的比值约为1∶1,可以实现常温生活污水SBR同步除磷亚硝化的稳定运行,为后续的厌氧氨氧化提供了合适的进水.

Study on Different Gradients of Sludge Retention Time and Selective Sludge Removal for Realizing Dephosphorization-Nitrosation System

The dephosphorization-nitrosation for two ways of discharging sludge in three different gradients of SRT (40,20,10 d) were studied with an SBR which treated domestic wastewater at normal temperature (20-25℃) . The results show that, with the decrease of SRT, the dephosphorization improves gradually and the volumetric load of ammonia removal reduces gradually. In the same condition of SRT, discharging sludge from the top of the sludge bed get a better phosphorus removal and higher volumetric load of ammonia removal than that from the bottom. In the long run, the stable operation of dephosphorization-nitrosation treating domestic wastewater by SBR at normal temperature was achieved by discharging sludge from the top of the sludge bed and controlling the sludge age at 20 d. In this condition, the effluent concentration of TP was 0. 1-0. 4 mg/L, TP removal rate was 95. 92% -97. 12%, the volumetric load of ammonium removal was 0. 12 kg/(m3·d) and the ratio of nitrite nitrogen and ammonia nitrogen in the effluent was about 1:1, which provided the appropriate inlet for anaerobic ammonia oxidation.