RIGHT CHOICE
Biological contact oxidation tank
(生物接触氧化池)
microorganism
少量污泥
The advantage
• ①Can effectively remove organic contaminants , and maintain good treatment effect • ②Simple and convenient operation , easy to manage , needless sludge return , sludge bulking phenomenon does not produce . • ③Generate less sludge , sludge particles larger , easy to precipitate
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.
Valveless gravity filter (重力式无阀滤池）
Pressure filter (压力滤池)
Ordinary rapid filter (普通快滤池)
Low cost simple and mature process easy maintenance Higher surface load stable operation
• ①More economical for large-scale wastewater treatment plant • ②The Mechanical sludge facilities have been produced stereotyped in series • ③Large volume, commonly used in large water sedimentation process
Sludge Thickening and Dewatering
We choose belt thickenerpress filter in sludge thickening and dewatering. The solids concentration of the sludge from belt thickener-press filter can be as high as 16% to 40%.
1. Elimination of microorganisms efficiently 2. Does not lose efficacy over time 3. No harmful byproducts 4. Disinfection power is independent of pH 5.Be economical
sewage Grille Remove larger or floating debris suspended solids Grit chamber Primary settling Remove ss 50%~60%, BOD 15%~20% , COD10%~15% Biological contact oxidation Secondary settling filter Remove sludge from the water, COD≈5% Free of disease-causing microorganism disinfection Clean water tank Water reuse Remove BOD≈90%, COD≈80% Remove suspended impurities and reduce water turbidity . organic compounds , bacteria and even viruses Remove a large proportion of inorganic particles
The disadvantage
• Filler 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 , these shortcoming can be avoided .
The Flow Chart of Waste Water Treatment Processes
primary settling Grit chamber Grille sewage
Sludge Thickening and Dewatering Biological contact oxidation Secondary settling Filter Disinfection
Clean water tank
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 。
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 :
(COD—200mg/L，refractory OM—20%) 姓 Team members: 名
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 process . After sewage treatment processes , COD must be reduced to less than 50mg/L , which comply with water quality standards .
Medium gille（中格栅） Pump（泵房） Fine grille（细格栅）
Grit chamber（沉砂池）
--------Remove a large 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）
Ordinary rapid filter (普通快滤池)
Disinfection Chlorine dioxide(Clo2)
• Chlorine dioxide，Clo2，is a greenishyellow gas at ordinary room temperature and pressure. • Clo2 is effective in destroying or preventing the spread of communicable disease Mechanism： Clo2 can through in cell and prevent the metabolism by oxidizing DNA or RNA, microoganism died.
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 are Ready-made equitment of Scraping machine to choose
• 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 .
Contain COD—200mg/L， refractory OM—20%
reuse water quality meeting the GB85 standard .
COD＜50mg/L , BOD＜10mg/L , refractory almost be removed