Study On Upgrade And Reconstruction Scheme Of Sewage Plant In DY Economic Development Zone And Analysis Of Operation Effection

With the promulgation and implementation of the Pollutant Discharge Standard for Municipal Sewage Treatment Plants(GB18918-2002),the effluent of many municipal sewage treatment plants in China will be upgraded to level A.Because the original sewage treatment processes are different and the quality of influent water is different,the selection of upgrading process is the key to ensure that the effluent meets the standards,and is also the core issue of upgrading and transformation of sewage treatment plants.The original designed effluent quality of DY Economic Development Zone Sewage Treatment Plant is Grade B standard of"Pollutant Discharge Standard for Urban Sewage Treatment Plant"(GB 18918-2002),which can not meet the requirements of Grade A standard.Therefore,the original treatment process should be upgraded.The purpose of this study is to study the upgrading process of sewage treatment plant in DY Economic Development Zone,and to provide technical support for the upgrading and reconstruction of the plant and its expansion project.In this paper,the upgrading and expansion of sewage treatment plant in DY Economic Development Zone is taken as the research object,and the treatment technology of the upgrading and expansion of the plant is studied in combination with the engineering practice.The main contents of the study include water intake analysis of sewage treatment plant,analysis of operation treatment effect and existing problems of the original sewage treatment process,selection and analysis of treatment process schemes for upgrading and expansion projects,optimization of design parameters and process design,analysis of operation effect,etc.According to the measured influent water quality index of DY Economic Development Zone sewage treatment plant,combined with probability analysis,the design influent water quality of DY Economic Development Zone sewage treatment plant upgrading and expansion project is determined to be CODcr 400 mg/L,SS 200 mg/L,NH3-N 40 mg/L and TP 5 mg/L.Drainage shall implement the first A discharge standard in GB18918-2002 Pollutant Discharge Standards for Urban Sewage Treatment Plants.Specifically,CODcr<50mg/L,NH3-N<5mg/L,SS<lOmg/L,TN<15mg/L,TP<0.5mg/L.The biodegradability of effluent from sewage treatment plant in DY Economic Development Zone is 0.4,which is easy to be biodegraded.Therefore,the biochemical treatment process is still used in the upgrading process.From the analysis of the treatment effect of the existing process,it can be seen that the upgrading process should strengthen the effect of nitrogen and phosphorus removal,strengthen the biological treatment section and increase the depth treatment.According to the requirements of influent water quality and effluent water quality standards,combined with the existing treatment process,the improved A2/O bio-tank+MBBR bio-tank+activated sand filter+ultraviolet disinfection process was adopted.The core of upgrading process is to add MBBR biological tank and activated sand filter after existing A2/O biological tank.The operation results show that the treatment effect is stable after upgrading the sewage treatment plant in DY Economic Development Zone.All the indexes meet the design requirements and meet the requirements of the first A discharge standard.The construction and commissioning of the upgrading and expansion project of the sewage treatment plant in DY Economic Development Zone have improved the effluent quality of the sewage treatment plant,helped to alleviate and eliminate the pollution of the sewage to the surrounding surface water and groundwater,and has important significance for improving the water quality of the surrounding waters..