Specifications

1.wide application
2.less sludge discharge
3.easy operation

 

1,Sewage characteristic

 

Water quality content low and steady, better degradability, belong to low concentration sewage

 

2,Process confirm

 

Traditional sewage treatment process can divide into biological membrane manner and activated sludge manner, biological membrane suitable to small water volume,steady water quality ,low concentration sewage water quality, better system commission.  Steady back operation, better operability. Sewage water quality set as traditional routine: COD_Cr ≤300mg/l,BOD₅ ≤200mg/l,

 

Combine our company past success practice, suggest sue biofilm manner treatment process, plan to adopt A/O biological contact oxygen process as main treatment manner. 

 

This project with high organic ingredients, BOD5/CODcr=0.6 , better biodegradability,due to ammonia nitrogen and organism content is high, especially organic nitrogen,  when biological degradation organism, the organic nitrogen will be express in the form of ammonia nitrogen, ammonia nitrogen is a key pollution control index, so such sewage treatment adopt anoxia oxic A/O biological contact oxidation process, so the biochemical tank divide into A grade tank and O grade tank two parts.

 

The sewage in equalize tank will lift to A grade biochemical tank, to go ahead biological treatment. In A grade biochemical tank , due to the sewage organism content is high, microorganism in anaerobic condition, now the microorganism is facultative , they will transform the organic nitrogen into  ammonia nitrogen, at the same time, using organic carbon source as electron donor, to make the NO₂-N,NO₃-N translate into N_2, and using part of carbon source and ammonia nitrogen synthesis new cellular material. so A grade tank with certain function of organic matter removal , relieve the organic load of follow-up O grade biochemical tank, to benefit to nitrification, and rely on high concentration organism in sewage , to finish denitrification, finally eliminate the nitrogen eutrophication pollution.  By A grade tank biochemical action, the sewage still some organism and higher ammonia nitrogen, in order to make organism further aerobic degradation, at the same time, when carbonification tend to finish, nitrification can smoothly going on , thus set O grade biochemical tank.

 

The outlet water from A grade tank will flow into O grade tank, the O grade biochemical treatment rely on autotrophic bacteria finish, they utilize organism resolve generate inorganic carbon or carbon dioxide in air as nutrients source, to make the ammonia nitrogen translate into NO₂-N,NO₃-N. a part of O grade outlet water enter into settling tank to sediment, another part backflow to A grade to proceed A grade tank to proceed internal recycle, to realize nitrifying purpose. All equip with padding in A grade and O grade biochemical tank, the whole biochemical treatment process all rely on many kinds of microorganism to finish.

 

The dissolved oxygen is control about 0.5mg/l in A grade tank, above 2.0mg/l in O grade tank, air water ratio 12:1; part of outlet water in O grade tank backflow to A grade tank, reflux ratio is 200%; part flow into vertical settling tank, to make solid liquid separation; the outlet water in settling tank after solid liquid separation, will be discharge out directly after disinfection. The settling sludge in settling tank will lift to sludge concentration tank by air lifting device, the concentrated sludge transport out as farming fertilizer.

 

      Sewage---- bar screen----- equalize tank-----A grade biochemical tank----- O grade biochemical tank ------ cleaning water tank---- discharge