深圳沙河水质净化厂及3#调蓄池工艺设计要点及特点

Key Points and Characteristics of Process Design of Shahe Underground WWTP and 3#Storage Tank in Shenzhen

沙河水质净化厂设计规模为旱季10万m^(3)/d,雨季额外处理10万m^(3)/d初期雨水,3#调蓄池设计规模为15.3万m^(3)。污水及初期雨水处理采用预处理+多段厌氧-好氧(AO)+二沉池+磁混凝高效沉淀池+精密过滤+紫外消毒的工艺,出水水质执行深圳市地方标准《水质净化厂出水水质规范》(DB 4403/T 64—2020)B级标准,其中总氮(TN)≤8 mg/L。污泥处理采用离心浓缩+低温热干化工艺,处理后含水率≤40%。作为国内首个将水质净化厂与初期雨水调蓄池深度融合的全地下式水污染治理综合体,项目采用多段AO耦合“3W法”(Wet-Weather-Wastewater法),并以此为核心提出了一种实现大规模污水及初期雨水高标准协同处理的系统解决方案,且无需大幅度增加污水处理设施体量、投资和运行成本。

The design scale of Shahe underground wastewater treatment plant(WWTP)is 100000 m^(3)/d in the dry season and an additional 100000 m^(3)/d of initial rainwater in the rainy season.The design scale of the 3#reservoir is 153000 m^(3).The process of the WWTP consists of pretreatment,step-feed multistage anaerobic-aerobic(AO)biological reactor,secondary sedimentation tank,high efficiency sedimentation tank,precision filters and ultraviolet disinfection,and the effluent water quality is required to meet grade B standard of the Shenzhen local standard Standards of Water Quality for Wastewater Treatment Plant(DB 4403/T 64—2020).Among them,TN≤8 mg/L.The sludge treatment process includes mechanical concentration and low temperature heat drying,and the sludge is transported out for incineration after the water content is no more than 40%.As the first fully underground water pollution control complex at home that deeply integrates the WWTP with the initial rainwater reservoir,the project innovatively adopts step-feed multistage AO and“3W”(Wet-Weather-Wastewater)process.Based on this,a system solution that can realize the high-standard collaborative treatment of large-scale sewage and initial rainwater without greatly increasing the volume,investment and operating cost of wastewater treatment facilities is proposed.