MBBR和MBR工艺在南方某用地受限污水处理厂扩建及提标改造中的应用

Application of MBBR and MBR Processes in Extention and Upgrading Project of a Southern WWTP under Limited Land Use

南方某污水处理厂现状规模为1.5万m^(3)/d,本次工程需扩建3万m^(3)/d,同时,出水水质指标提升至《地表水环境质量标准》(GB 3838-2002)中V类标准(TN除外)。工程预留用地有限,传统的生物处理工艺很难满足扩建及提标需求,故现状一期工程采用移动床生物膜反应器(MBBR)工艺对生物池进行升级改造,二期新建工程采用AAO生物池+膜生物反应器(MBR)工艺。建设完成后,污水厂总处理规模为4.5万m^(3)/d,出水水质稳定达到并优于《地表水环境质量标准》(GB 3838-2002)中V类标准(TN除外)。污水厂吨水占地面积为0.66 m^(2),一期万吨水产泥量为1.09 t,二期万吨水产泥量为0.64 t,吨水电耗为0.43 kW·h。MBR膜池在膜通量为19.84 L/(m^(2)·h)时,运行较稳定,出水优良,该案例可为今后同类型污水处理厂的设计改造提供参考与借鉴。

The existing capacity of a wastewater treatment plant(WWTP)in southern area is 15000 m^(3)/d.This WWTP needs to be expanded by 30000 m^(3)/d and the effluent should be upgraded to Class V critria in Environmental Quality Standards for Surface Water(GB 3838-2002)(except TN)at the same time。Because of the land shortage and the high level effluent quality,conventional biological treatment process is difficult to meet the requirements.So moving-bed biofilm reactor(MBBR)process is adopted for the first phase of the project to upgrade the existing bio-tank and AAO+membrane bio-reactor(MBR)process is adopted for the second phase project.After the construction,the total treatment scale of the WWTP is 45000 m^(3)/d,the effluent can stably reach the class V standard in Environmental Quality Standards for Surface Water(GB 3838-2002)(except TN).The WWTP covers 0.66 m^(2) of per ton water.The sludge production of 10000 tons of water in the first phase is 1.09 t and the second phase is 0.64 t.The electricity consumption is 0.43 kW·h of per ton water.When the membrane flux is 19.84 L/(m^(2)·h),the operation of the MBR is relatively stable and the effluent is excellent.This project can provide a reference for the design of similar WWTPs.