Study On The Treatment Of Landfill Leachate By The Coupled Process Of MBR And Microelectrode

In recent years, urban living garbage in our country has been a growing threat to the urban and peri-urban ecological environment. In the waste disposal process, it could generate a lot of landfill leachate, which could seriously endanger the lives of people. The efficiency of dealing process is poor, because of the variation range of the concentration of poor biodegradability, Ammonia and CODcr of landfill leachate.The microelectrode coupling MBR, as integrated reactor treatment process, was used to deal with the landfill leachate with high ammonia, high concentrations of refractory organics. By the method of combining the characteristics of electrochemical-biological-membrane retention, the organic load of landfill leachate was reduced, the biodegradability of wastewater was improved, and the sludge microorganisms fungi was activated to deal with ammonia nitrogen and degrade the organic matter.In the experimental process, the effluent of secondary sedimentation tank in the process of the process was analyed in Nanchang. Through probing the influence of process parameters to the concentration of ammonia nitrogen and CODcr, such as electric current density, distance between plates, concentration of chloride ion, and reaction residence time. The optimized single factor conditions were found:electric current density was12mA/cm2, the distance between plates was10cm, concentration of chlorine ion was4000mg/L and reaction residence time was8h. Under these conditions, the removal rate of CODcr reached90%, the removal rate of ammonia nitrogen reached92%, and the concentration of ammonia nitrogen and CODcr in the effluent have reached the discharge standards of industrial water (GB16889-2008). By these conditions to design experiments, the optimized conditions after corrected were:electric current density13mA/cm2, the distance between plates10cm, concentration of chlorine ion4200mg/L and reaction residence time10h. The Design-Expert-V8.0.6.1was used to fit the equation of the removal rate of the ammonia nitrogen and CODcr. The influence of each single factor for removal rate was discussed. To fumble the treatment efficiency and current efficiency in the various stages of the microelectrode coupling MBR integrated reactor in detail, the reactor was divided into the electrolytic treatment, biological treatment, membrane module treatment find the removal rate of CODcr was respectively35%、34.9%、9.19%, the removal rate of ammonia nitrogen was respectively44%、35%、9.97%. After calculated, the current consumption rate of the microelectrode coupling MBR integrated reactor was27.54KW·h/t, which greatly reduces the current consumption compared with the consumption rate of separate electrolysis100to200KW· h/t. In summary, it was proved that the microelectrode coupling MBR integrated reactor was not only with higher removal rate, but also with lower current consumption than the single process to deal with the landfill leachate.Detect the water quality and nature of the sludge in the integrally reactor, and use the technical means of GC-MS to analyze the organic pollutants in landfill leachate, determine the changes of types of organic pollutants in the influent and effluent. Through determining the sludge, the author found that there was no change between these various groups in different sledges. And find that the polysaccharide is a more important element than the protein in the pollution of the film forming elements through detecting the content of protein and the ribose and calculating and comparing the EPS. According to the changes of the membrane flux and the Darcy’s law, the model of the membrane flux was deduced, and use the model to forecast the membrane flux to find that the maximum deviation was11.03%, the minimum deviation was2.52%. Through monitoring the variation of the running time of membrane flux, it was found that the specific trends of the membrane flux guided the control of the membrane flux in the process of using of membrane module. The generation of membrane fouling and the widely used cleaning method were studied, after cleaning the used membrane module and restoring the membrane flux, it was found that the cleaning effect was good, the recovery rate of membrane flux reached99.72%after once cleaned by the water, acid, alkali.