The Demonstration And Design Of The Technical Upgrading Scheme Of A Sewage Treatment Plant In Dalian City

With the rapid development of urban economy,the development and utilization of water resources have been gradually paid attention to.In order to protect the water resources effectively,it is necessary to comprehensively control the city pollution,build urban sewage pipe network and sewage plant,effectively improve the rate of sewage collection and treatment,and reduce the cost of treatment to achieve this goal.Take the steps.Compared with developed countries,China’s sewage treatment plant upgrading project is still in its infancy,facing two aspects of technology and operation cost.The research on the design and design of the proposed upgrading of the sewage treatment plant is a comprehensive study of the data of the sewage treatment plant.It is selected from many aspects,such as cost budget and management operation,and finally determines the best project.The first stage of the sewage treatment plant is in an overload operation state,and the water volume fluctuates greatly,with the rule of seasonal variation.The influent COD_Cr,BOD₅,SS and other indicators have even more than the design values,but most of the time period are lower than the design values.NH₃-N,TN,TP and other indicators have exceeded the design values for most of the period.In reference to the initial results of the two phase of the project,the design scale of the first phase of the wastewater treatment plant was15×10⁴m³/d,and the standard of the standard of the surface water environmental quality standard（GB3838-2002）was carried out by the standard of the standard of the surface water environmental quality.In this paper,the water quality of the first phase of the 2013-2017 year sewage treatment plant is analyzed.The concentration of the cumulative frequency of 90%guarantee rate is selected as the evaluation of the water quality of the import and export water,and the evaluation value of the current status of the water import and export of the sewage treatment plant is determined.The water intake index of the sewage plant,the effluent of the sewage plant and the effluent from the two sink are analyzed,and the results are analyzed.In order to improve the requirements,the NH₃-N and TN should be removed,and the advanced treatment process should be added to control the effluent indexes such as SS and TP.Through the demonstration,the present condition preprocessing and biochemical treatment can satisfy the stable operation of the first grade B effluent.In order to reach the surface leveling IV water standard,the"coagulation sedimentation+filtration"depth treatment system should be added.The three sets of biological nitrogen removal technology were selected,and the biological nitrogen removal process was finally determined by adding biological aerated filter and denitrifying filter,and the reaction sedimentation process selected efficient flocculating sedimentation tank,and the filtration system was selected with the precision filter.According to the results of the project design,the process flow of the lifting scheme was determined:"the original treatment process+intermediate lifting pump station+fine grille+BAF+high efficient flocculating sedimentation tank+precision filter pool+contact disinfection channel".The advanced treatment process of the standard upgrading is 2 groups,which can run independently,with a single scale of 7.5×10⁴m³/d and a total variation coefficient of k_z=1.3.The construction of the upgrading project has reduced the pollution of the river basin and ensured the healthy water consumption of the living industry.This design study provides a basis for similar similar upgrading projects.