| Because of the incomparable advantages to traditional wastewater treatment process, the high efficient and useful treatment process named MBR that consist of microbial degradation of pollutants and membrane separation technology is attracting attention of water treatment researchers in the world. The advantages of MBR are high quality water, simple flow, lower excess sludge production, fewer area occupied and so on. However, their widespread applications are hindered by their elevated energy consumption and the high costs of investment for the membrane modules. In this study, we investigated a modified an improved MBR system that utilized a cost effective woven fabric instead of nonwoven as the filter material in MBR modules for solving this problem. The fabric bioreactor. Besides simple flow, fewer area occupied et al as MBR, NWFBR also has the advantages of low cost, low energy consuming and high intensity. The new-style process is a promising technology for small-scale wastewater treatment, and has great significance to study.In this study, the performance of synthetic domestic wastewater treatment was evaluated in the NWFBR with different pore diameter nylon woven as filtration material at same operating conditions, in order to choose which filtration material is the best one. This study investigated the treatment performance of simulated domestic wastewater with the NWFBR,almost all effluent water quality can meet our hope. In order to optimize the process parameters of NWFBR, for its wide application of FBR in wastewater treatment, the factor that affects the effluent efficiency and the factor that affects the stable operation of NWFBR were analyzed in this paper. This study also discussed the fouling of the nylon woven fabric. The main results are shown as follows:(1)The results show that NWFBR with different mesh number nylon woven of500mu、800mu and1000mu has good removal efficiency for contamination. System COD removal efficiencies are all over90%, and the average removal efficiencies are92.2%、93.5%and93.2% respectively.The average removal efficiencies of NH3-N are92.9%、93.6%and93.9%respectively.NWFBR has high removal efficiency for SS and turbidity,the residual tubidity is lower than3NTU.The sewage fluxs of the three nylon woven fabrics are significantly higher than the fluxs of the conventional membrane and the flux of the800mu nylon woven fabric is the highest. Consolidated compare the removal efficiencies and the flux of the three nylon woven fabrics, the study used the800mu nylon woven fabric for optimal filtering material.(2)The NWFBR with800mu nylon woven eliminated suction pumping in the membrane filtration of the effluent over the entire operational period of45d. The results show that NWFBR with the mesh number nylon woven of800mu has good removal efficiency for contamination. System COD removal efficiency is93.8%, the average removal efficiency of NH3-N is96.6%, the average turbidity of effluent is1.5NTU.(3)NWFBR has high resistance to sludge bulking. In the NWFBR, since nylon woven fabric as the solid-liquid separator could filtrate the level of suspended solids in the sludge supernatant, the effluence when sludge filamentous bulked was better than before.(4)The optimum operating condition of NWFBR with800mu nylon woven is that:the optimum HRT is25h, the optimum MLSS is about5g/L, the optimum BOD loading rate is from0.08to0.12kg BOD5/(m3·d).(5)The total filter resistance of NWFBR is lower2orders of magnitude than the conventional membrane filtration resistance. The inherent resistance of NWFBR is lower3orders of magnitude than the conventional membrane filtration resistance. The filter cake accounts for99%of the total resistance.(6)Using the SEM、EDS、IR to detect the matters that cause the nylon woven fabric fouling.The results show that the organic matter causes the pollution mainly and the main performance is the soluble microorganism product(Soluble Microbial Products,SMP).(7)Analysis and comparison of four cleaning methods, ultrasonic cleaning is the best. |
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