| Submerged Double-shaft Rotary Anaerobic Membrane Bioreactor(SDRAnMBR) has the advantages of compact structure, small foot area, and it is suitable for dealing with some organic wastewater with high concentration.At present, the research of membrane bioreactor is relatively concentrated on the external (aerobic) membrane bioreactor, because compared to these two ways of MBR, the rate of membrane pollution of SAnMBR is faster and more difficult to be controlled. It is the reasons that restrict people's research and application on SAnMBR. This test especially designed the SDRAnMBR for the membrane pollution problem in the above-mentioned SAnMBR which is not easy to control. The characteristics of the reactor is revolving (cocurrent) the membrane module movement, which can weaken the concentration polarization and the formation of gel layer on the membrane surface by the turbulent flow and staggered flow formatted from spin module, at the same time in the reactor also Can form a rotating three-phase flow effects, so that it can effectively slow down the process of membrane pollution and extend the service life of membrane. The research is studied the start-up characteristics, the removal rate of COD and its influence factors, anti-pollution performance and impacts that the sludge characteristics produce to membrane pollution in the SDRAnMBR system, which is operated by experiments with artificial beer wastewater. The main research results are as follows:(1) The SDRAnMBR system completed the start-up of reactor and sludge acclimation just 20 days in the experiment at the constant temperature of 32 degrees and constant HRT of 24 hours, which was inoculated by anaerobic granular sludge, the removal rate of COD could be up to 91% and the average removal rate was 83.95%. In addition, the SDRAnMBR system has the impact resistance of the load capacity anti impulsionload and it hadn't acidification phenomenon in the period of sludge acclimation.(2) In the stable operation phase, SDRAnMBR has a good effect for beer wastewater. When the COD concentration of system water inlet ranges from 1721.5 to 2269.9mg/L with the average of 2025.3mg/L and the volume load ranges from 2.07 kgCOD/m3·d to 4.54 kgCOD/m3·d, the COD concentration of effluent is in the; range of 65.7 to 141.4mg/L whose average is 101.6mg/L and the removal rate of COD remained from 92.2% to 96.8% with a average of 94.9%. In addition, in the stable operation period, although the VFA concentration of system water inlet fluctuated from 331.8 to 514.6mg/L, the system can still maintain a steadily efficient performance, which shows that the system has a good buffer capacity.(3) In water flux experiment for new membrane, it found membrane flux of SDRAnMBR fall as the rotation speed of membrane (membrane surface shear flow rate) increases. So in the premise of considering reducing membrane pollution furthest, low-speed operation should be used as far as possible. In the period of stable operation, the system can run with steadily efficient removal under the conditions of relatively larger flux and low TMP.(4) Membrane filtration resistance was small and the process of membrane pollution was slow throughout the course of the experiment. Corresponding membrane filtration resistance just increased from 0.276×1012 to 1.152×1012m-1 as membrane rotation speed heightened from 100rpm to 150rpm.(5) Throughout the course of the trial, MLSS, EPS and the viscosity of sludge were all on the rise as the increase of operating time, but sludge particle size gradually decreased and particle size range narrowed as the increase of travel time and membrane rotation speed.(6) It was known that membrane filtration resistance mainly caused by the filter cake layer and the membrane hole by comparing the scanning electron microscope image of the new membrane and polluted membrane. But the mud cake layer was thin, sparse and multi-hole on the surface of membrane and there were only a small number of irregular particles on the membrane section.
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