Sreen And Oxygen In SBR Reactor To The Influence Of The Aerobic Granular Sludge Formation And Stable Operation Of Research

The formation of aerobic granular sludge (AGS) is the special growth form of biofilm and the cell immobilization process itself. Mature aerobic granular sludge has high concentration, compactal structure, which sedimentation performance is good and its resistance to impact load capacity is strong, at same times the characteristics of sewage purification effect is good. But in the system in terms of the characteristics of aerobic granular sludge itself, because of the diversity of its formation mechanism and influencing factors of particles and the process conditions of the system operation and diversification of micro-organisms, it is easy to cause the poor stability, the air is large, high energy consumption, which become a threshold in the engineering practical application promotion.In the paper, we set up a screen in the traditional SBR reactor. In this paper,it study how a screen SBR reactor of configurations and oxygenaerobic influence granular sludge formation and stability of the experiment. Increased sheet can improve the flow field in the reactor and the aeration hydraulic shear strength of particles, it is advantageous to the mass transfer and biological floc since cohesion, improving the reaction performance; Under the lower intensity of oxygen, increase the dissolved oxygen concentration and reduce the energy consumption,it can create environment for the growth of microbial adhesion.(1) the effect of screen configurations. In the circumstances with system operation parameters exactly same, it test the traditional SBR (1#) and web plate SBR (2#) reactor parallel. It found:1#,2#reactor in15d,10d form aerobic sludge granules respectively, the mature state was achieved at30d,25d; Under the same air, within the same cycle, the equilibrium concentration of dissolved oxygen is6mg/L,8mg/L respectively in1#and2#reactor; in30d,2#reactor aerobic granular sludge for COD, ammonia nitrogen and TP removal rate as high as5%in1#;1#and2#reactor particle size concentration distribution is between0.5-5mm and2-3mm, in the2#reactor, the formation of the aerobic sludge granules structure is more compact, the sedimentation performance and the stability of the particles is better, water quality is good; In the1#reactor,the aerobic sludge granules appear in for viscous in90d,2#reactor work well. Through the experiment, we can concluded:the screen set up in the reactor under low oxygen, it increased the DO and shear strength, reduced the energy consumption; the formation of aerobic granular sludge structure performance is more stable to change the hydraulic flow pattern inside the reactor for the growth of biofilm carrier,and the removal rate of COD, ammonia and TP increased significantly, water quality is good.(2) The analysis of the features of the oxygen influence the formation of aerobic granular sludge and stability analysis of the features in SBR reactors. In#2-#6mesh plate in the SBR reactor, its aeration intensity respectively set up after0.5m3/h,0.3m3/h,0.4m3/h,1.0m3./h,1.5m3/h, doing parallel experiment. It can found that when Q=0.3m3/h, COD, ammonia nitrogen and TP removal rate is around60%, only DO6mg/L in3#reactor, which the highest form of aerobic sludge particle size is larger, but the structure is loose, not stable, easy to expand and the effluent water quality is poorer; Between0.4-1.0m3/h, the removal rate of COD, ammonia and TP increases with the increasea of aeration intensity, which are over85%, and DO also will increase; When Q=1.5m3/h, DO, COD, the removal rate of ammonia nitrogen and TP is similar with the1.0m3/h; MLVSS/MLSS ratio reduce with the increase of aeration intensity:when high aeration strength, shear force and DO is too high, which is not good for the growth of microorganisms. Extracellular polymers content (EPS) and PS/PN enhanced as the improvement of aeration intensity. When the reactor run to120d,3#and4#appear the aerobic granulars has lightly sticky sludge expansion, in the5#and6#, the aerobic granular appere sludge disintegration phenomenon, which conclude the optimum aeration intensity in SBR reactor is0.5m3/h.