| As a brand-new process Dynamic membrane bioreactor combined with Integrated vertical-flow constructed wetland was used to deal with domestic sewage.The main research focused on the removal effect and mechanism in domestic sewage made by this hybrid system;The removal rate of different pollutants under different hydraulic loadings were discussed and so it was with HRT,volume load and other factors that may have impacts on the disposal effect of the bioreactor;And the characteristics of the micro-organisms during different periods in the bioreactor,together with the causes of membrane pollution,rules of membrane flux changing,restoration after cleaning,were also studied in the research.Finally came to these following main conclusions:1) The hybrid system met GB18918-2002 emissions level A standard and the water quality standards in all experiment stages;Of all the three differernt operation conditions,the third one achieved the best results.The hybrid system has a rather high average removal rate of COD,ammonia,TN,TP and Turbidity,which attained 93.68% 93.49%85.13%and 98.60%respectively;And the HRT for DMBR was 6h,as the load capacity was 0.09～1.15Kg(COD)/m3·d,and the membrane aeration capacity of 0.6m3/h;HRT for IVCW was 9h,as the hydraulic loading was 0.309m3/m2·d;2) The impact on the treatment of COD under different HRT conditions was not obvious,but for TN and TP,it has a relative visible effect;In the case of COD load volume during 0.031～0.245Kg(COD)/m3·d,and TP load volume during 0.00046～0.00394Kg(TP)/m3·d,the removal of pollutants which made by the reactor was on the rise;And COD load volume in the 0.416～1.053Kg(COD)/m3·d,TP load volume 0.00394～0.0067Kg(TP)/m3·d,the effects was on the decrease while the volume load was on its rise;The removal rate of TN has a positive relation with TN Load capacity, especially when TN volume load was during 0.006～0.063Kg(TN)/m3·d;3) Through taking photos of the micro-organisms in activity sludge during different periods of experiment,a wide variety of micro-organisms were found.The dominant micro-organism during the three different conditions was Vorticella,and Spirostomum minus appeared at the end period;4) Within 180min,dynamic membrane could form spontaneously on the surface of a new membrane,but because of the relative large hole as well as the operation reasons,making membrane was easily contaminated;With the increasing of aeration capacity,membrane contamination could be effectively slowed down;5) The results of cleanout membrane that contaminated by using clean water,citric acid and NaOH in different concentrations with different clean durations showed that the effect of cleaning and duration has a directly positive relationship.With 1%NaOH to carry out 5h Washing was the most effective operation condition,from which the membrane flux could achieved a 96.25%restoration of initial flux.
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