| Membrane Biological Reactors (MBRs) are combinations of biological treatmenttechnology and membrane technology. MBR has many advantages such as great fluxwater quality, resisting sudden load, and little surplus sludge, long settle time, brieftechnical flow, easy and tight construction, small plant area, highly automation,saving money and human resource. So MBR is regarded as a very efficient method inwater or wastewater treatment and water reuse technology, which can solve withlacking clean water in China.However, now MBR did not replace the traditional water treatment in water orwastewater plant industry totally and swiftly; that is because there still are a fewdifficult problems in this new tech. For example, heavy membrane pollution, activemicroorganisms declining, hard-decomposed material accumulating, low efficiency intransporting oxygen, hard settlement with surplus sludge, waste chemical liquidconducing second pollution, expensive equipment and energy.In the study, PVDF micro membrane was enhanced by spaying nanometer TiO2;one MBR is set in this kind of membrane, and another MBR is set in membranewhich is not enhanced. So the flux water quality and quantity, as well astrans-membrane resistance, were compared between the two different MBRs.This study began from fall to winter at the water temperature bellow 20℃,when the activated sludge is domesticated. The influent COD, is above 500 mg/L onaverage; and influent BOD5/CODor=0.20.4; under this kind &conditions, the fluxwater quality of two MBRs came to the standard of CJ25.1-89. Then it came to thestable period.In the first step of the stable period, the conclusion is that the flux water quantityof the enhanced MBR is larger than the not-enhanced one, under the condition of thesame flux water quality; however, the trans-membrane resistance is opposite. Also inthis experiment, the optimum trans-membrane pressure (TMP) is 30 kPa. The cleanwater trans-membrane resistance of the enhanced MBR is 1/2 less than that of thenot-enhanced one. At the same time, the flux water quantity of the enhanced MBR is 67.5% larger than that of the not-enhanced one, under the condition of TMP being 30kPa; the corresponding data is 46.7 % under 40 kPa TMP.In the second step of the stable period, adjust the aeration rate to be 0.3 m3/h, 0.1m3/h, 0.5 m3/h, and then compare flux water quality, trans-membrane water quantityand trans-membrane resistant. Resultly, 0.3 m3/h is best parameter. Too high or toolow aeration rate would affect the treatment more or less.At last, after observing the electron microscope photos, the effect by thedifferent parameters were analyzed.
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