A Sewage Treatment Plant Project Preliminary Design

Water is indispensable to the survival of humans and all living things,and it is the precious natural resource for industrial and agricultural production,economic development and environmental improvement,which can not be replaced.Our country belongs to the monsoon climate,where because of uneven distribution of water resources in space and time,there are large differences of the natural environment,and the northern is a water shortage area.In recent decades,with the development of industry and urban construction,especially the explosion of urban population,urban environmental pollution has become worse and worse in our country,especially the problem of water pollution.A large amount of sewage has discharged into rivers and lakes without effective treatment,which has resulted in the serious situation of water pollution in China,and further exacerbated the shortage of water resources.Serious situation of water pollution and shortage of water resources have become the prominent problems to seriously restrict our social economy sustainable development,damage the ecological environment,and affect people's lives and health,which need to be solved urgently.Therefore increase the intensity of urban sewage treatment is imperative.The task of this design is the preliminary design of a county sewage treatment project,with the recent daily sewage handling capacity of 20000 tons per day,and long-term capacity of 40000 tons per day.This project mainly services urban area and industrial agglomeration area of the county.Influent quality of the wastewater treatment plant is designed on the basis of present situation forecast,while according to the requirements of local water environment protection and environmental protection departments,effluent quality is up to the A level of primary standard of"Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant"(GB18918-2002).According to the sewage water quality and the discharge standard of wastewater treatment process,with comprehensive analysis and comparison,this design recommends the process of "Pretreatment + Modified Carrousel Oxidation Ditch + Reaction and Sedimentation Tank + Fiber Rotating Disc Filter + Contact Disinfection".The process has the features of low investment,small occupied area,good effluent quality and so on.Sludge produced by sewage treatment process of sewage treatment plant are transported outward and landfilled after concentration and dehydration.The project actively improves the urban living environment,reduces urban pollutant emissions,decreases pollution load,and protects the water environment quality of Huaihe River,and it will produce remarkable social and economic benefits,which is required to carry out the scientific development perspective,and build the socialist harmonious society.