Research On Design And Operation For Upgrading And Reconstruction Of A Sewage Treatment Plant

The upgrading project of a municipal sewage treatment plant was the main research background of the project,Through the analysis of the operation of the existing treatment process of the sewage plant,the effluent of the treatment process was required to meet the first level A criteria specified in the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant(GB18918-2002).The results was as follows:1)In this paper,the plant was mainly domestic sewage and designed with the treatment scale of 10.0×104tons/d,adopting coarse grille,fine grille,sediment,anaerobic,oxidation ditch and disinfection process.The effluent quality of which was based on the Secondary standard of Integrated wastewater discharge.Through analyzing the water indexes,operation and emission requirements,the suitable biological treatment technology"Anaerobic,Anoxic,MBBR" and advanced treatment technology "coagulation and filtration" were selected.2)The design project was made combining water process,the structures and plane arrangement."Anaerobic and anaerobic"and "MBBR" was difined as secondary processing technology.Newly built flocculation sedimentation tank and V-filter.Design and calculation are performed.3)Operation control of the city sewage treatment plant were finished.The results showed that,the water quality of COD,TP,SS,NH3-N and TN was 450mg· L-1,4mg·L-1,200mg·L-1,50mg·L-1 and 65mg·L-1,while the concentration in the discharge was 11?39mg L-1,0.1?0.5mg·L-1,2.6?5.9mg L-1,0.6?2.9mg L-1 and 5.5?1.2mg·L-1,respectively,the effluent quality could meet the A in first grade standard.After transforming the total operation cost 0.571yuan/tons of water,and some of the new operation cost 0.207 yuan/tons of water.Pollution emissions of COD,SS,TN,NH3-N and TP can be reduced by 1818,730,2051,383 and 25.6 tons per year,respectively.The reductions of COD,SS,NH3-N and TP were 13.2%,11 4%,27.8%and 23.3%higher than before.Through benefit evaluation,the project has good environment effect and the social effect.