| Membrane bio-reactor(MBR) is a high-efficiency water treatment process which is often difficult to be effectively met by conventional activated sludge process. The advantages of MBR are simple flow, fewer area occupied, high quality water, lower excess sludge production and so on. Membrane bioreactor has been developing for several decades and always broadening its application fields, and has attracted more and more attention. Capital costs of the membrane bioreactor process are substantially influenced by the membrane cost, which has restricted the practical application of the membrane bioreactor in large scale. Nowadays in the world, membrane filtration module is in the situation of high performance with high price and low price with poor performance.In this study, membrane was replaced by non-woven fabric to form a new process: Fabric Bio-reactor (FBR). Besides simple flow, fewer area occupied, high quality water et al as MBR, FBR 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.This study investigated the treatment performance of simulated domestic wastewater with the FBR, almost all effluent water quality can meet the national criterion of reclamation water. In order to optimize the designing parameters of FBR, for its wide application in wastewater treatment, the factor that affects the effluent efficiency and the factor that affects the stable operation of FBR were analyzed in this paper. The performance of synthetic domestic wastewater treatment was evaluated in the FBR with different pore diameter non-wovens as filtration material at same operating conditions.The results show that FBR with different pore diameter non-wovens of 60μm, 100μm and 180μm has good removal efficiency for contamination, system CODcr removal efficiencies are all over 85% , and the average removal efficiencies are 91.80%,90.57% and 89.47% respectively. The average residual of CODcr is all below 50mg/L. FBR has high removal efficiency for SS and turbidity .As an example this paper investigated the removal efficiency of NH3-N and Total phosphorus by FBR (60μm). The average removal efficiencies of NH3-N is 75.98% and only26.49% of TP by FBR process.FBR has high resistance to impact load. The removal efficiency is directly proportional to the material and pore diameter of non-wovens, HRT, aeration intensity and sludge characteristic. In this study, the pore diameter of non-wovens is not suitable to be bigger than 100μm in the condition of which there is a high quality water; the optimal HRT is 6h; the optimum aeration intensity is about 0.3～0.5 m3/h and keeping the dissolving oxygen is about 3.0 mg/L; when MLSS reached a certain extent, sludge loading has less influence on removal efficiency, the optimal MLSS is about 2500mg/L.During the experiments, the mechanism of non-wovens pollution and the cleaning method after pollution were investigated systematically to offer some useful information for the application of FBR. The experiment results demonstrated that the non-wovens pollution was due to the inner fouling of the non-wovens for the non-wovens character. Adheres of microbe to the surface of non-wovens fiber is the main reason for the non-wovens flux decline. Water head drop (WHD) or original flux, aeration intensity or stagger velocity of flow and sludge characteristic are the main reason for non-wovens pollution. The total filter resistance with 100μm pore diameter non-wovens is 2.145×1011m-1, while the filter cake accounts for 80% of the total resistance. Non-woven fabric flux recovery after water cleaning and mechanical cleaning is about 50%～60% and above 90% after chemical cleaning, the corresponding optimal cleaning time is 6h.The results of filtration mechanism of FBR shows that the solid and liquid are separated by non-woven fabric through mechanical sieving, superficial adsorption, bridging flocculation and secondary interception, the four separate mechanisms play different roles for different materials and pore diameter. In the process of system running, self forming bio-dynamic membrane is formed on the surface of non-woven fabric which brings the system a high removal efficiency for organism and the separation for solid and liquid.
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