四级A/O镶嵌MBBR工艺在高原污水厂的设计应用

Design and application of four-stage A/O and MBBR process in plateau wastewater treatment plant

我国西部高原地区的自然条件普遍较差,需加强水资源的保护利用。某高原污水处理厂原为四级A/O工艺,采用移动床生物膜反应器(MBBR)进行改造后,在常年低温和超水量运行的情况下,出水中的COD、BOD5、氨氮、总氮、悬浮物和总磷浓度均可稳定达标。改造项目施工迅速、占地紧凑,采用原池改造,土建费用低。不停水进行改造的施工方式,使得污水厂在正常运行的情况下,实现生物池的升级。悬浮载体对硝化菌属的富集能力强于活性污泥,因此悬浮载体的硝化能力强于活性污泥;活性污泥对有机物的去除能力及对聚磷菌属的富集性均高于悬浮载体。二级MBBR悬浮载体对氨氮的去除能力要强于一级MBBR,而一级MBBR悬浮载体对有机物的去除性能强于二级MBBR。改造后,项目运行电费为0.322元/m^(3),直接运行费用为0.378元/m^(3),可为后期高原地区污水处理项目的实施提供一定数据支撑和技术借鉴。

The natural conditions in the western plateau region of China are poor,and it is necessary to strengthen the protection and utilization of water resources.A plateau wastewater treatment plant originally had a four-stage A/O process.After the transformation with moving bed biofilm reactor(MBBR),the COD,BOD5,ammonia nitro⁃gen,total nitrogen,suspended solids and total phosphorus in the effluent could meet the standards stably under the condition of low temperature and over water operation.The construction of transformation project was rapid with compact area,and the original pool was used,with low civil construction costs.The construction of transformation without water interruption made it possible to upgrade the biological ponds under normal operation of the wastewater plant.The enrichment ability of suspended carriers for nitrifying genera was stronger than that of activated sludge,so the nitrification ability of suspended carriers was stronger.Activated sludge had higher organic removal capacity and enrichment of phosphorus accumulating genera than suspension carrier.The ammonia nitrogen removal ability of secondary MBBR suspension carrier was better than primary MBBR,while the organic removal ability of primary MBBR suspension carrier was better than secondary MBBR.After the transformation,the operating electricity cost was 0.322 RMB/m^(3) and the direct operating cost was 0.378 RMB/m^(3),which provides some support and technical ref⁃erence for the implementation of wastewater treatment projects in plateau areas.