| The biological fluidized bed, which is filled in with inertial grain as carrier covered with biological film, having the advantages of larger specific surface area, higher mass transfer rate and more mixed liquor suspended solids, is one of the biological film processes.In the course of land fill disposal, water and pollutant dissolved in water are released by the urban refuse through the influence of compaction and biological degradation. Urban refuse percolation liquid is composed of this water and precipitation mixed with the overland runoff. Because of the levity of the urban refuse percolation liquid's quality and quantity, there is no well-established disposal layout for it. In most cases, idiographic disposal layout is brought forward aiming at specific conditions of the landfill site and other economic or technical request.In this dissertation, biological fluidized bed system was used to dispose water containing high concentration of organic pollutant and nitrogen and urban refuse percolation liquid for the removal of the organic pollutant and nitrogen. Based on that, the efficiency of biological fluidized bed in the disposal of urban refuse percolation liquid was studied, so were the influential factors in the disposal process and the management of them.The main work of the dissertation includes three experiments: the start-up and restart-up of the biological fluidized bed, the disposal of water containing high concentration of organic pollutant, nitrogen, and urban refuse percolation liquid, using biological fluidized bed, and the removal of heavy metal using Silicate bacteria.The experimental results indicate: 1) the bio-film culturing in anaerobic biological fluidized bed is a long-term complex process which needs a hard condition; the attachment of flora to the carrier is an important factor that affects the bio-film culturing process; aerobic precoating can accelerate the anaerobic bio-film culturing process and reduce the risk in the strat-up process by stabilizing the ecological structure in the biological fluidized bed; 2) methanogen always dies or runs off in the intermission term of the anaerobic biological fluidized bed; attention should be paid to the pH value of the liquid in the bed to prevent acidification in the restart-up process of the anaerobic biological fluidized bed; at the same time , adding anaerobic sludge to the bed is necessary; 3) anaerobic-anaerobic-aerobic biological fluidized system is efficient in the removal of the organic pollutant and nitrogen from water; denitrogenation efficiency can increase with higher recirculation rate which can increase the load of aerobic bed so that the COD removal efficiency can decrease; 4) instead of mass transfer rate , reaction time is the governing factor in the degradation process of persistent organic pollutants.; anaerobic ferment device is advised to be installed before the fluidized system because of the disadvantage of biological fluidized bed in hydraulic residence time; something can poison the microbe exist in the urban refuse percolation liquid so that the biological structure can be destroyed in the case of direct disposing of the urban refuse percolation liquid with biological fluidized bed; 5) Silicate bacteria can remove heavy metal ion from liquid in which the concentration of heavy metal is lightly over standard by flocculation, biological concentration and metabolizing something that can chelate with heavy metal.
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