1、,Team members:,姓名,(COD200mg/L，refractory OM20%),Considering water reuse , we designed the sewage treatment processes include pretreatment, biochemical treatment and tertiary treatment . Biological treatment of domestic sewage in the present is the most economical and appropriate sewage treatment pro
2、cess . After sewage treatment processes , COD must be reduced to less than 50mg/L , which comply with water quality standards .,The Flow Chart of Waste Water Treatment Processes,Grille,Grit chamber,sewage,primary settling,Biological contact oxidation,Filter,Disinfection,Clean water tank,Secondaryset
3、tling,Sludge Thickening and Dewatering,Grille (格栅）,-To retain larger or floating debris suspended solids，such as fiber, broken skin, hair, wood, fruit, vegetables, and other plastic products。In order to reduce the processing load of the follow-up treatment structures, and make it work 。,Medium gille
4、（中格栅）,Pump（泵房）,Fine grille（细格栅）,-To retain larger or floating debris suspended solids，such as fiber, broken skin, hair, wood, fruit, vegetables, and other plastic products。In order to reduce the processing load of the follow-up treatment structures, and make it work 。,Grit chamber（沉砂池）,-Remove a lar
5、ge proportion of inorganic particles (such as sand, cinder, etc.),Advection-type grit chamber （平流沉砂池）,Aeration-type grit chamber （曝气沉砂池）,Bell type grit chamber （钟式沉砂池）,Centripetal Radial-flow Sedimentation Tank,Strong Points,Using mechine to shovel the sludge,Stable operation,easy to manage,There ar
6、e Ready-made equitment of Scraping machine to choose,Biological contact oxidation tank,(生物接触氧化池),microorganism,少量污泥,The advantage Can effectively remove organic contaminants , and maintain good treatment effect Simple and convenient operation , easy to manage , needless sludge return , sludge bulkin
7、g phenomenon does not produce . Generate less sludge , sludge particles larger , easy to precipitate The disadvantageFiller may cause blocked phenomenon , water distribution and aeration are not uniform ,which makes appear dead in the some area . PS：Through the reasonable design and operation , thes
8、e shortcoming can be avoided .,The secondary sedimentation tank,The Radial-flow sedimentation(辐流式沉淀池),The secondary sedimentation tank,The Radial-flow sedimentation(辐流式沉淀池),The advantage :More economical for large-scale wastewater treatment plantThe Mechanical sludge facilities have been produced st
9、ereotyped in seriesLarge volume, commonly used in large water sedimentation process The disadvantage :Sludge equipment is huge, complex structures and high cost.High quality construction.,Filter（滤池）,Through the processes of sewage treatment above, waste water has reached the effluent standard . But
10、in order to achieve the purpose of water reuse ,we choose sand filtration as tertiary treatment of sewage .,There are many filters , such as ,Pressure filter(压力滤池),Ordinary rapid filter(普通快滤池),Siphon Filter(虹吸滤池),Valveless gravity filter(重力式无阀滤池）,Ordinary rapid filter(普通快滤池),Low cost,simple and matu
11、re process,Higher surface load,easy maintenance,stable operation,Disinfection,Chlorine dioxide(Clo2),Chlorine dioxide，Clo2，is a greenish-yellow gas at ordinary room temperature and pressure.,Clo2 is effective in destroying or preventing the spread of communicable disease,Mechanism：Clo2 can through i
12、n cell and prevent the metabolism by oxidizing DNA or RNA, microoganism died.,SchematicDiagram of Clo2 Addition,Clo2 Producing equipment,reuse,Water injector,Water supply,Disinfectant- Clo2,Disinfectant,Finished Water tank,advantage,1. Elimination of microorganisms efficiently2. Does not lose effica
13、cy over time3. No harmful byproducts4. Disinfection power is independent of pH5.Be economical,Sludge Thickening and Dewatering,We choose belt thickener-press filter in sludge thickening and dewatering. The solids concentration of the sludge from belt thickener-press filter can be as high as 16% to 4
14、0%.,The belt thickener-press filter can squeeze sludge into filter cake with two belts after flocculation.,Its operation is simple, general staff can handle the entire process after a short period of training.,High Performance of Separation,Large Amount of Sludge Treatment,Automatic Continuous Opera
15、tion,Low Power Consumption,Advantages:,sewage,Grille,Grit chamber,Primary settling,Biological contact oxidation,Secondary settling,filter,disinfection,Clean water tank,Water reuse,Contain COD200mg/L，refractory OM20%,Remove larger or floating debris suspended solids,Remove a large proportion of inorg
16、anic particles,Remove ss 50%60%,BOD 15%20% ,COD10%15%,Remove BOD90%,COD80%,Remove suspended impurities and reduce water turbidity . organic compounds , bacteria and even viruses,Remove sludge from the water, COD5%,Free of disease-causing microorganism,reuse water quality meeting the GB85 standard . COD50mg/L , BOD10mg/L , refractory almost be removed,
