厌氧-局部循环供氧生物膜技术处理农村污水

通过模拟农村生活污水水质和间歇进水特点,利用“厌氧-局部循环供氧生物膜”技术,研究该工艺对有机物、氮、磷的去除效果.厌氧池和局部循环供氧池有效容积比为1∶1.6,曝气装置位于局部循环供氧池中间底部,环形导流板将局部循环供氧池分隔成中间好氧区和四周缺氧区,斜管沉淀池前置到厌氧池与局部循环供氧池之间,出水端设置循环水池.装置连续稳定运行12个月,平均进水量为140 L/d,生物反应区HRT为1.3d.监测结果表明,出水COD、BOD、NH3-N、TN和TP平均浓度分别在40.31、3.38、2.69、11.98和0.75 mg/L,达到了国家城镇污水处理厂污染物排放指标(GB-18918-2002)中的一级排放标准.研究表明,厌氧-局部循环供氧技术是一种适合农村分散污水处理的新工艺,可有效减轻农业面源污染.

Treatment of rural domestic sewage with anaerobic and local circulating oxygen-supply biofilm technology

The amount of organic matter, nitrogen and phosphorus removal in the simulative rural domestic sewage was investigated using the anaerobic and local circulating oxygen-supply biofilm technology with the intermittent feeding method . The available volume rate between the anaerobic tank and the local circulating oxygen-supply tank was 1:1.6. The aeration device was located on the bottom of the local circulating oxygen-supply tank, in the center of which there was an unnular splitters to separate central aerationic region and around anaerobic region. The inclined-tube sedimentation tank was arranged in the middle of the anaerobic tank and local circulating oxygen-supply tank. There was one water circle tank near the water outlet. This equipment continuously run stably for twelve months. The capacity for treating sewage of this equipment was 140 L/d and the hydraulic retention time in bio-reaction zone was 1.3 d. The average effluent concentration of COD, BOD₅, NH₃-N, TN and TP were 40.31, 3.38, 2.69, 11.98 and 0.75 mg/L, respectively. Those effluent rate can meet the first class criteria specified in the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB 18918-2002).Those results illustrated that the anaerobic and local circulating oxygen-supply biofilm technology was suitable for treating the domestic sewage in rural areas and could efficiently reduce agricultural non-point source pollution.