Study On Integrative Muitistage Biofilm Reactor For Medium And High Wastewater Treatment In Small Twon

The paper in view of the medium and high concentrated small town sewage, develops the organic matter, the nitrogen and the phosphorus removes, deposition, filter craft units collection and so on disinfection to the integrative multistage biofilm equipment, and has obtained the parameter of the reactor highly effective at simultaneous nitrification and denitrification. The multistage biofilm and sequence uncoupled environment constructed in the reactor has been suitable for the sludge reduction and the excess sludge quantity obviously reduces. At the same time the best operating parameter has been obtained in integrated multistage biofilm reactor processing the medium and highly concentrated sewage water, especially under the winter low temperature. And using the means of intermittent aeration and excluding excess sludge to enhance the removal of phosphorus in the continuum flow biofilm reactor. Infall through the multi- spots improves the carbon source lacked question for the nitrogen removal from the high-nitrogen and low-carbon small town sewage. Draws the following main conclusion:(1) The medium concentrated small town sewage treatment test indicated: With the conditions of the temperature=25℃, the organic load rating 1.2 KgCOD/m3 d, the nitrogen load rating=0.28KgN/m3 d, HRT=6.0h, the seweage (COD=320mg/L, TN=68mg/L, NH4+-N=62mg/L) treated, the outlet water's COD, TN, NH4+-N respectively are 15mg/L, 14mg/L, 7.35mg/L, achieved a national level discharges standard. Comparing the similar reactor enhances 30%.(2) The high nitrogen small town sewage treatment test indicated: With the conditions of the temperature=20℃, the organic load rating=0.85KgCOD/m3 d, the nitrogen load rating=0.27KgN/m3 d, HRT=9h and two infalls to enter the reactor, the high nitrogen seweage(COD=320mg/L,TN=100mg/L, NH4+-N=85mg)treated,T,NH4+-N and TN removing rate respectively is 91.81%, 79.35%,and outlat water's COD,TN and NH4+-N respectively are 16mg/L, 19.8mg/L and 6.86mg/L,and achieved a national level discharges standard. Through two infalls to enhance the carbon source use efficiency, with one infall compared to, may cause the TN removal rate enhancement under the same condition about 10%.(3) The winter cold temperature test indicated: With the conditions of the temperature=5～8℃,the nitrogen load rating=0.16KgN/m3 d, HRT=16h and DO=7～...