Study On Magnetic Loading Reinforced Activated Sludge Process In The Treatment Of Urban Landfill Leachate

In this study, we used the pretreated urban landfill leachate(coagulating sedimentation+acidification tank+UASB) as the experimental water, and then studied the fundamentalsof the magnetic loading reinforced activated sludge technology, and its using in thetreatment of urban landfill leachate. Study pointed in four stages:(1) The first stage is "experimental studies on single stage magnetic loadingreinforced aeration-sedimentation tank". Focus on the study of the fundamentals of themagnetic loading reinforced activated sludge technology, and play good foundation for thefollow-up stages.(2) The second stage is "experimental studies on magnetic loading reinforced A/O/Oactivated sludge process (continuous flow)". Focus on the study of technique on the basisof the first stage.(3) The third stage is "experimental studies on magnetic loading reinforced SBRactivated sludge process (intermittent flow)". Focus on the study of technique on the basisof the first stage.(4) In order to overcome the imperfection of magnetic loading reinforced traditionalactivated sludge technology, and give it the opportunity to play low cost, convenientmaintenance and management advantages in the comparison with MBR and other excellentprocesses in the field of high concentration of activated sludge technology, so we proceedthe fourth stage: new technology development.Through a series of experiments and analysis found that:(1)Magnetic loading reinforced activated sludge technology can effectively improvethe settling performance of activated sludge, indirectly improve the microbial quantity andthe efficiency of economical biological process. Magnetic loading reinforced SBRobviously get more MLVSS than aeration sedimentation tanks in the two previous stages.(2)Landfill leachate has high concentration of COD and ammoniacal nitrogen,so theprocessing effort of single stage activated sludge process is poor despite magnetic loadingreinforced. In addition, although single stage magnetic loading reinforced SBR increasedmicrobial quantity and joined the anaerobic mixing process, but for urban landfill leachate,the treatment effect is not ideal, it is necessary to take multistage tandem process. (3)Combining "the three-stage activated sludge process" and "traditionalpre-denitrificated activated sludge process", we used the A/O/O process, and thenreinforced it with the magnetic loading technology. Achieved satisfactory treatment effect.Experiments proof that, this is a good process selection for the landfill leachate.(4)In the fourth stage, we have designed a new type of magnetic loaded aeration tank.This tank can overcome the restrictions of secondary sedimentation tank and return sludgefacility, with the strong magnetic (activated sludge-magnetic powder)separator and thebuilt-in weak magnetic (solid-liquid) separator. So it can greatly increase the microbialquantity of the aeration tank. This tank can overcome the restrictions of aeration andstirring, with the medium bubble blow aerator or the underwater aerator. This tank canovercome the magnetic powder uneven arrangement shortcoming effectively，with theliquid magnetic powder arrangement method.