曝气生物滤池的短程硝化特性

摘要

通过控制进水pH值实现曝气生物滤池的短程硝化.工艺运行结果表明.对于进水pH值为8.22～ 8.57,NH4+-N平均容积负荷为0.5 kg/(m3·d),水温为17.5～20.2℃,曝气生物滤池溶解氧质量浓度平均为4.5mg/L的条件下能够同步实现95％的NH4+-N去除率和80％的NO2--N积累率.通过分析FA和FNA沿滤池高度的变化特征,发现滤池底部(0～5 cm)区域短程硝化反应主要由FA控制,中部(5～15 cm)区域是由FA和FNA共同掌控；而上部区域(15～50 cm)则是由FNA控制,FNA沿滤池高度的快速增加是确保工艺实现稳定亚硝酸盐积累的重要原因.%Short-cut nitrification was carried out in a biological aerated filter (BAF) by controlling the pH value of influent. Process operation results showed that, for the pH value of 8.22 ~ 8.57, ammonia volumetric loading of 0.5 kg NH4+-N/(m3·d), and water temperature of 17.5 - 20.2℃, BAF could realize 95% of ammonia removal efficiency and 80% nitrite accumulation rate simultaneously as oxygen concentration was 4.05 - 4.88 mg/L. By analyzing the variation characters of FA and FNA along the height of reactor, it was found that the accumulation of nitrite at the bottom region (0-5 cm) of the filter was mainly controlled by FA, while that at the top region (15 - 50 cm) of the filter was mainly controlled by FNA. Ab for the middle region (5-15 cm) of the filter, the accumulation of nitrite was controlled by both FA and FNA. The rapid increase of FNA concentration along the height of the filter is vital for the maintenance of stable nitrite accumulation.