The Craft Design Of 35,000m3/d Sewage Treatment Plant
ABSTRACT
Sewage in China mainly comes from two main aspects: the industrial sewage and the municipal, the aquicolous environment was polluted due to plenty of raw waste water discharge into the river.
This is a design about the sewage treatment plant. According to the primitive data of the design and demanding for water quality, namely require the denitrification and phosphorus removal to reach the second class discharge standard. CASS craft is chosed.
In preliminary treatment, the original water enters coarse screening in order to remove heavy solides and floatable material, in case that it influences the working of the following treatment and the pipeline. And then wastewater is promoted into the medium screening by pump, after that it enters the aerated grit chamber. It is used to remove bigger inorganic sand of heavy density, by this way, the density of organic material in mud can be improved. The above-mentioned sewage disposal is the physical disposal stage.
It is one of activated sludge treatment. The craft process is short, and it has lesser structures and equipments, do not establish the primary sedimentation tank, and there are no regulating tank and secondary sedimentation tank. The activated sludge can reflux automatic, so it could be in an low standard of investment, consume, floor space, eassier for manage. This treatment is stable and reliable, its BOD5 and SS removal rate are all in 90%-95% or higher. More than 85% COD can be removed after the craft, and the result of the removal of nitrogen and phosphorus are obvious.
Key word: Municipal Sewage Treatment Sludge treatment CASS