Optimization Study On Excess Sludge Disintegration Combined Fluid Shear With Ultrasonic Cavitation

A large number of excess sludge generated by municipal wastewater treatment increasingly become a serious environmental and social problems. Because of the huge excess sludge production and land scarcity, the sanitary landfill method, etc. currently main used is unsustainable; also because excess sludge contains large amounts of organic matter, phosphate and other resources, therefore, recycling and reduction of excess sludge treatment become an ineviTablele choice in the context of the development of resource recycling and environment-friendly society.Anaerobic digestion technology is an effective way in residual sludge reduction and recycling, but traditional anaerobic digestion process has slower reflects, long sludge retention time, digester volume and other disadvantages. Crack of sludge can fully release the resources available, and increase efficiency of anaerobic digestion and other resource recovery methods, but also can achieve reduction of solids sludge. Therefore, the remaining sludge crack is necessary pretreatment process in sludge reduction and recycling.Generally there is the status quo of high energy efficiency and low break in current excess sludge crack method, so how to improve the efficiency and significantly reduce cracked energy consumption and cost is a serious problem waiting to solve. Based on literature data and research group studies, this study made a kind of treatment process that using with fluid shear method to crack sludge initially, and then using the ultrasonic cavitation method to enhance crack, the process can reduce residual sludge crack energy consumption,and improve the effect of excess sludge crack.To verify the above assume, this study made fluid shear crack experiments by the organize stamp mill for the remaining sludge, and then made ultrasonic cavitation crack experiments by ultrasonic instrument. Based on the literature data, the ultrasonic cavitation and fluid shear crack comparison experiments,we can get that the fluid shear is a residual sludge floc break significant processing method,and ultrasonic cavitation is more efficient and better crack method; then according to the advantages and characteristics of fluid shear and ultrasonic cavitation method, we carried out two sets orthogonal experiments with the first fluid shear and then ultrasonic cavitation and ultrasonic cavitation first and then fluid shear. We get the the optimal combination of fluid shear and ultrasonic cavitation. Finally, we made the fluid shear, ultrasonic cavitation, ultrasonic cavitation first and then fluid shear and fluid shear firs and then ultrasonic cavitation comparative experiment, and then verified the theory that first fluid shear and then ultrasonic cavitation process with high efficiency.This study verified the first fluid shear and then ultrasonic cavitation process has high efficiency, and fluid shear can enhance the effect of ultrasonic cavitation. And we also found the optimal combination of fluid shear and ultrasonic cavitation.This combination can reduce the residual sludge crack energy consumption, and improve the efficiency of the crack.So it can better achieve the excess sludge reduction and recycling. This study explored a new method in the field of crack sludge, but also providing an experimental basis for the study of cracking sludge and bacteria and related mechanical mechanism.