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The subject of two different forms of membrane bioreactor (MBR), the composite membrane bioreactor (CMBR) and submerged membrane bioreactor (SMBR) treatment of domestic sewage experimental study of a small test of both optimum operating conditions, pollutant removal efficiency in the long-running and extracellular polymeric substances (EPS) of sludge activity and membrane fouling. The research shows that: the optimum operating condition for the CMBR and SMBR line are HRT = 6h, DO = 2.5mg / L, pH = 7.1 8 .1 and C / N = 18.2 3 8.9. More consistent in the long run, the CMBR and SMBR removal of COD and NH 3 -N, COD average removal rate gt; 95% effluent of COD lt; 20 mg / L, NH 3 -N lt; 1.5mg / L. CMBR and SMBR average removal rate of TN were 67.46% and 54.45%, CMBR better than OF SUBMERGED MEMBRANE BIOREACTORS FOR. Both poor TP removal of the CMBR and SMBR TP average removal rate of 21.97% and 22.99%, respectively. The study showed that the two MBR treatment effect are relatively stable in the long-term operating conditions. Eckenfelder and Monod model, MBR COD and NH 3 -N degradation rate and run time, the results showed that: when the CMBR and SMBR the running time, respectively, for the 59d and 50d the degradation rate of the COD a maximum of 3.09 and 2.72; NH 3 -N of the maximum degradation rate at run time, respectively 50d, 7.59mg / L H and 43d of 9.96mg / L · h. Studied the optimum conditions of the cationic resin Extraction EPS. The results show that the resin the dosage 60g/gVSS, and extraction time 4h shaker frequency 200rpm when EPS extraction was better. By experimental observations and theoretical analysis, mathematical model between the the EPS extracted amount of impact factors, and verify the accuracy of this model. Found that the content of activated sludge per unit volume in the EPS and COD degradation rate constant K1 good correlation, the higher the content of activated sludge per unit volume of the EPS, the faster the rate of degradation of COD, the activity of the sludge is also more better. The two MBR over the membrane resistance increases with the increase of the membrane surface EPS content, there is a good correlation between the two. CMBR unit volume lower EPS content in activated sludge, membrane surface EPS gathered speed lower than the SMBR, therefore, the CMBR membrane fouling rate slower than SMBR. CMBR, despite the increase in the filler makes the project cost has increased, but the effect of treatment of TN was significantly better than the SMBR, and lighter membrane fouling, and therefore more application value.
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