EBIS工艺在全地下污水处理厂改造中的应用

Application of EBIS Process in Reconstruction of Underground Sewage Treatment Plant

大连市某全地下污水处理厂处理规模为8000 m^(3)/d,原采用BF-A/O摇动床处理工艺,出水水质执行《城镇污水处理厂污染物排放标准》(GB 18918—2002)一级A标准。原BF-A/O工艺缺少厌氧段,无化学除磷措施,缺氧及好氧停留时间远小于设计停留时间,导致总磷及总氮超标,而现状全地下污水厂改造空间局促、改造周期较短且系统不能停车。本次选择的高效一体化生物处理系统(EBIS)工艺在原调节池、BF-A/O摇动床及消毒池体中进行改造,将原清水池改造为磁混凝系统,强化化学除磷,分组分期进行改造,对原土建池体充分利用,极大缩短了改造周期,同时保证系统不停车。试运行结果表明,经过EBIS-磁混凝系统处理后,出水水质稳定达到一级A标准。项目实际总投资为3803.90万元,新增直接运行成本为0.40元/m^(3)。

The treatment scale of an underground sewage treatment plant in Dalian is 8 000 m^(3)/d.The original key process is BF-A/O shaking bed,and the effluent quality is required to meet the first level A limit specified in the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant(GB 18918-2002).The original BF-A/O process lacks anaerobic section and chemical phosphorus removal measures,and the residence times of anoxic and aerobic tanks are far less than the designed values,resulting in the total phosphorus and total nitrogen exceeding the discharge standard.The space of the reconstruction project is limited,and the construction needs to be completed in a short period without suspending production.The original regulating tank,BF-A/O shaking bed and disinfection tank were transformed into the energy biochemical intelligent control system(EBIS) process,and the original clear water reservoir was transformed into a magnetic coagulation system to improve the chemical phosphorus removal.The project was carried out in different groups and stages,and the original civil structures were highly utilized,which greatly shortened the transformation period without suspending production.The trial operational results showed that the effluent quality met the first level A limit after being treated by the EBIS-magnetic coagulation system.The actual total investment of the project is 38.039 million yuan,and the direct operating cost is increased by 0.40 yuan/m^(3).