| The dynamic membrane that was made of nylon mesh as filter material was treated with campus wastewater. Effect of dynamic membrane formation, treatment effect, operation process and physical and chemical properties of dynamic membrane and interception of dynamic membrane effect was analyzed in the paper.(1) A dynamic membrane bioreactor(DMBR) was constructed by using nylon mesh as membrane material for domestic wastewater treatment. The results showed that the air is too large, the dynamic membrane formation is more difficult, the air is too small, the dynamic membrane formed for a long time. 400 mesh membrane pore size water flux is big, low turbidity, high strength, good durability, more conducive to the operation of the dynamic membrane bioreactor. It is found that with the rising of water head as DMBR water power, the initial flux gradually increased, dynamic membrane formed easily under the 10 cm head. Particle size analysis showed that the particle diameter between 0-250 microns, and different size particles had been removed at different levels by particle size analysis in the process of the dynamic membrane formation.(2) A dynamic membrane bioreactor(DMBR) was constructed by using nylon mesh as membrane material for domestic wastewater treatment, and also the forming and regeneration processes of dynamic membrane were investigated. It is analyzed that the COD is removed : one is interception performance of dynamic membrane for the insoluble particulate matter and macromolecular organic matter; the other is the physical and chemical adsorption and biodegradation of the activated sludge in mixture for organic matter; The ammonia nitrogen is mainly removed through microbial degradation; the removal of TP is mainly realized through the mud in the DMBR. It was found that DMBR showed a superior performance with the average removal efficiencies of COD, NH3-N, TP and turbidity at 91.2%, 98.6%, 34.7% and 96.0%, respectively for about 80 days.(3) In view of the dynamic membrane formation process, according to the change of membrane flux and turbidity, it can be divided into three stages: rapid attenuation stage, slowly lower stage, stable stage. Air backwash way can remove cake layer on the surface of the membrane, but some physical pollutants that can’t be removed still exists, but the way of air backwash combined with scrub can remove some physical pollutants that can’t be removed.(4) Through a microscope, activated sludge and cake layer are different on the morphological characteristics, the activated sludge floc is relatively loose, and cake layer is relatively dense. By FTIR and EDX analysis, large particles, colloidal and biological polymer(such as proteins and polysaccharides) play an important role in dynamic membrane formation and some physical pollutants that can’t be removed in dynamic membrane.(5) By measuring the parameters of the water concentration of the influent, mixed liquor and effluent, and conclusion is that COD mainly exist in the form of particulate matter and colloid, the ammonia nitrogen and total phosphorus mainly exist in the form of dissolved states. Through EEM and GFC analysis, the dynamic membrane has a certain interception effect for organic matter, and SEPS has a certain influence for dynamic membrane fouling as well as the effect of water. |
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