A/O脱氮工艺的改造实践

Reconstruction practice of A/O nitrogen removal process

岳阳市南津港污水处理厂一期工程采用前置缺氧/好氧脱氮工艺,出水总磷一直难以达标。一年来,在不新增构筑物的情况下,通过改变缺氧池内溶解氧的含量、调整曝气池污泥浓度及回流比、加大剩余污泥的排放量等工艺参数,将原缺氧/好氧脱氮工艺改造为厌氧/好氧除磷工艺,从而使出水TP≤1.5mg/L,NH3-N≤5.0mg/L,达到《城镇污水处理厂污染物排放标准》(GB18918-2002)的一级B标准。

Pre-Anoxic/Aerobic nitrogen removal process is used in the first phase project of Nanjinggang wastewater treatment plant in Yueyang city, the effluent phosphorus was not able to reach the discharge standards. In the past one year, under the condition of not adding new structure,the original Noxic/Aerobic nitrogen removal process was reconstructed to Anaerobic/Aerobic phosphorus removal process by changing the concentration of dissolved oxygen in the Anoxic tank;reducing mixed liquor suspended solids and sludge return ratio in the areation tank; adding the volume of surplus sludge.The effluent NH3-N and TP is less than and equal to 5.0 mg/L and 1.5 mg/L, meeting the class I-B criteria Specified in Discharge Standards of Pollutants for Municipal Wastewater Plant （GB18918-2002）.