Influence of Optimized Sludge Reflux Mode on Multilevel AO-MBR Process
A test device with treatment scale of 0.15 m3/h was used to carry out an AO-MBR process to treat low C/N urban wastewater.Best sludge return form was explored to reduce the impact of high dissolved oxygen sludge return on the front biochemical tank,by optimizing the sludge return mode,dissolved oxygen and sludge concentration control and other measures.Eventually,the effluent quality to reach the surface level Ⅳ standard was achieved.The results showed that in the form of coupled MBR process,biochemical tank could significantly ensure the dissolved oxygen environment of each reaction zone and maintain the balance of sludge concentration in each reaction zone by multi-stage reflux,so as to further improved the effluent quality.When the water temperature was below 12 ℃ and the influent TN was 23～33 mg/L,the reflux mode 4 could stably ensure that the TN removal rate reached more than 60％and the effluent TN reached about 10 mg/L.When the influent TP was 2～4 mg/L,the TP removal rate was more than 85％,and the effluent TP was less than 0.3 mg/L.
multilevel AO processsludge refluxdissolved oxygen controlMBR processmulti-point influent
万方数据
维普
