Research On The Aerobic Digestion To Sludge In Urban Sewage Treatment Plant

The public has further demanded to deal with sludge with the public being moreand more strict on the environment. Tianjin East Suburb Sewage Treatment Planttreats sewage 400,000t/d and produces dry sludge by filter pressing about 300t/d. Thethesis discusses the aerobic digestion and dewatering for condensed sludge andanaerobic digestion sludge, which produces in Tianjin East Suburb Sewage TreatmentPlant. The purpose is to realize reducing sludge quantity and improve the performanceof sludge dewatering and settling. The conclusions are:1.Aerobic digestiona. The volatile substance content in sludge decreases and the smell debases afteraerobic digestion.b. Anaerobic digestion sludge is stabilized and the quantity is reduced, on theother hand,germs are killed after digested.c. It enhances the dissolved oxygen concentration in sludge by increasingaerating intensity to quicken the degrading rate of organic matter and to improve thedewater ability of sludge. The volume of sludge reduces. The reduction of the aerobicdigestion alone is more distinct than the anaerobic digestion alone. The anaerobicdigestion sludge is the most distinct in reduction after aerobic digestion.d. The fine-dispersed sludge particles caused by the strengthened aerating worsenthe settlement ability of sludge.e. The quantity of fecal-coliforms goes down when anaerobic digestion sludgegoes on aerobic digestion.2. Dewaterabilitya. The optimal ratios of the CPAM and the TM added into sludge are 2% and 3%respectively, and the corresponding dewatering ratios are 37% and 43.5%. Thedewaterability effect of TM is better than that of the CPAM.b. The CPAM is easier to get and cheaper than the TM and the quantity of theCPAM we added to the sludge is less than that of the TM. Take economy intoaccount,The CPAM is more economic and more practical medicament.c. The bigger the ratio of the anaerobic digestion sludge is, the worse thedewaterability of sludge is.