| The main treatment technology of municipal waste is sanitary Lanfill currently. Landfill leachate, produced in the process of landfill disposal, is one kind of organic wastewater of high concentration. Its characteristics are complex component, deleterious and much fluctuation of water quality and quantity. Pollution control of landfill leachate has becomed a great research project in envoirnmental protection field in the present. Membrane bioreactor,which appeared recently, is a new technology for wastewater treatment and reuse. It has particular advantage for treatment of the organic wastewater of high concentration and slow-biodegradable nature. Anaerobic membrane bioreactor and biological hydrolysis/aerobic membrane bioreactor were used to treat unstabilized and stabilized landfill leachate in this paper. The efficiency and mechanism of treatment of landfill leachate by MBR were investigated, which would offer theoretic basis and experience for the application of MBR.Removal characteristics of contamination, the changing laws of the nature of sludge microorganism, attenuation laws of membrane flux and resume methods of fouled membrane, the changing laws of the characteristics of organic pollutant during treatment and filtration performance of sludge were investigated through treatment the leachate by MBR in this dissertation respectively. Experimental results show:(1) Submerged anaerobic MBR was used to treat lanfill leachate for the first time. Removal characteristics of contamination, attenuation laws of membrane flux and resume methods of fouled membrane, the effect of high Ammonia-N on treatment of landfill leachate by Anaerobic MBR were investigated respectively. For the unstabilized landfill leachate, COD removal efficiency was more than 70% when OLR was between 1.3 kgCOD/m3d and 5.7 kgCOD/m3d and HRT was more than 2d. Declining of membrane flux rapidly and cleaning of membran frequently were caused by the dead-end filtration and poor precipitation of anaerobic sludge. Fouled membrane could be resumed by periodicalshaking, leaving unused and backwashing. When Ammonia-N concentration was less than 3600mg/L, the COD removal effect of anaerobic MBR was not affected obviously. These results enriched the theory of wastewater treatment by anaerobic MBR, and offered theoretic basis and technical support for the treatment of the organic wastewater of high concentration and slow-biodegradable nature by anaerobic MBR.(2) For the unstabilized landfill leachate, COD removal efficiency of "biological hydrolysis/aerobic MBR" process was between 80% and 88% when influent contained 400~7600mg/L COD and HRT was l~3d. When HRT was l~3d, Ammonia-N loading rate was 0.07~0.50kgNH3-N/m3d and the return activated-sludge ratio was 300%, Ammonia-N and TN removal efficiencies of the process were more than 99% and 75% respectively.(3) The changing laws of several microorganism natures of anaerobic sludge and aerobic sludge during long-term operating of MBR were investigated. The coenzyme F420, the max specific production methane activity and VSS/SS of anaerobic sludge maintained 0.41 -0.47gCODCH4/gVSSd, 0.43 - 0.55 u mol/gVSS and 0.55 - 0.57 respectively, indicating that long-term operating without draining excess activated sludge would not damage the anaerobic sludge activity. The VSS/SS, the mean size of sludge particulate and dehydrogenase activity of aerobic sludge decreased from 0.76, 46.39 m and 9.7 gTTC/mgVSS.h to 0.64, 27.62 m and 1.8 gTTC/mgVSS.h and SV, SVI, ECP and viscosity of aerobic sludge increased from 33.4%, 64.6mL/g, 161.4mg/gVSS and 1.25mPas to 100%, 180mL/g, 295.8mg/gVSS and 2.47mPas, indicating that long-term operation without draining excess activated sludge would damage the anaerobic sludge activity obviously, In order to maintain sludge activity, periodical draining excess activated sludge should be adopted.(4) When Ammonia-N loading rate was less than 1.5kgNH3-N/m3d, Ammonia-N removal rate of aerobic MBR was more than 80%...
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