Research Of Shenyang Western Sewage Treatment Plant Upgrading And Reforming Process And Analysis Of Operation Effect

In order to protect and improve the quality of the water environment,the discharge standards of municipal wastewater treatment plants are continuously improved in China.In particular,the implementation of The Pollutant Discharge Standard of Urban Sewage Treatment Plant(GB18918-2002)proposed stricter standards for total nitrogen and phosphorus in effluent.However,the effluent of municipal sewage treatment plants constructed in recent years in China generally fails to meet the first-grade A discharge standard.Therefore,many municipal sewage treatment plants are facing upgrading and transformation.The original designed effluent quality of Shenyang Western Sewage Treatment Plant is in second-level discharge standard,which must be upgraded to the first-level A discharge standard according to the regulation.The purpose of this research is to study the upgrading process of Shenyang West Wastewater Treatment Plant,and provides technical support for the plant upgrading.This research takes the upgrading project of Shenyang Western Sewage Treatment Plant as the research object,through investigation and analysis of the influent quality,combining with the existing treatment process,the upgrading and transformation process of the plant is studied.The main contents of the research cover the analysis of treatment effect and existing problems of original process,the analysis and determination of the influent quantity and quality,the selection and analysis of the upgrading process plan,the design parameter optimization and process design,and the operation effect analysis.According to the measured data 2017.01-2017.10,the design capacity of Shenyang Western Sewage Treatment Plant has been confirmed to be 150,000 m3/d.According to the measured data 2015.01-2017.06,at the guarantee rate of 85%,the designed influent quality is determined as CODcr=320mg/L,BOD5=135mg/L,SS=170mg/L,NH3-N=40mg/L,TN=41mg/L,TP=5.4mg/L.Furthermore,Emission Standards for Pollutants in Urban Sewage Treatment Plants(GB 18918-2002)first-class A standard is employed to the plant effluent quality,and the specific values are CODcr?50mg/L,BOD5?10mg/L,SS?10mg/L,NH3-N?5mg/L,TN?15mg/L,TP?0.5mg/L.The influent quality analysis results show BOD5/COD of 0.42,which indicates good biodegradability,therefore,influent of Shenyang Western Sewage Treatment Plant belongs to biodegradable sewage.Based on influent quality characteristics combined with original treatment process,the two-stage treatment process of this upgrading project will adopt HYBAS technology,advanced treatment will use "high-efficiency clarifier+V-type filter",phosphorus removal process will apply "biological phosphorus removal technics+chemical phosphorus removal technics",auxiliary carbon source will utilize sodium acetate,disinfectant process will employ "UV sterilization+auxiliary sodium hypochlorite".The operation results show that after upgrading and reconstruction,the removal capacities of nitrogen,phosphorus and other pollutants of Shenyang Western Sewage Treatment Plant have been improved,also,the water quality indicators of the effluent have reached the design water requirements.In conclusion,through implementation of the upgrading project,effluent quality of Shenyang Western Sewage Treatment Plant has reached Emission Standards for Pollutants in Urban Sewage Treatment Plants(GB18918-2002)first-class A standard.The upgrading project will relieve Xihe River pollution,thus functioning a key role in improving the water environment quality of Xihe River and its surroundings and promoting the development of western industrial corridor in Shenyang city.