Study On Characteristics Of SMP Characteristics Variation And Mechanism Of Freeze-Thaw Dewatering Anaerobic Sludge Reduction

Due to the characteristics of high moisture content,complex composition,and unstable properties of sludge,sludge reduction has always been a technical problem.At present,the mechanism of sludge reduction technology has not yet been clarified.It is of great significance to ascertain the sludge reduction mechanism for improving sludge reduction technology.This study proposes to add an anoxic-anaerobic sludge storage tank(SAA)to the sludge return section of the anoxic aerobic system(AO)to form an in-situ sludge reduction system(AO+SAA)and to treat residual pollution at the end.The mud is further dehydrated(freeze-thaw method)to reduce the total amount of sludge.By studying the mechanism of the sludge reduction technology,it provides some theoretical support for improving the sludge reduction technology.The research content and results are as follows:(1)The effect of anoxic-anaerobic sludge storage tank on the sludge yield of AO system.The resultsthat the effluent quality of AO+SAA system does not change significantly and meets the effluent quality requirements compared to AO system.However,the former reduced sludge production by 33.38%compared with the latter.(2)The characteristics of Soluble microbial products(SMP)and Extracellular polymeric substances(EPS)in hypoxic-anaerobic sludge storage tanks were studied.The results showed that:1.The acid concentration of small molecules in the anaerobic sludge storage tank(1146 ppb)is muchhigher than that in the anoxic sludge storage tank(12 ppb),which makes the sludge produced by the AO + SAA system easier to be used by microorganisms;The total organic carbon in the anoxic reactor and the aerobic reactor in the 2AO+SAA system issimilar to that of the AO system,but it contains more small molecular substances and humic acids,and the anoxic-anaerobic sludge storage tank The reflux and the microbial self-metabolism are responsible for the high proportion of small molecules in the AO+SAA system.3 Due to the change of molecular weight distribution,the biodegradability of SMP and Loose type extracellular polymeric substance(LB-EPS)increased significantly compared with that of...