[Objective] The aim was to study the effects of ultrasonic on the dehydration function of sludge and internal mechanism.[Method] Taking the residual sludge from a municipal domestic sewage treatment plant as an object...[Objective] The aim was to study the effects of ultrasonic on the dehydration function of sludge and internal mechanism.[Method] Taking the residual sludge from a municipal domestic sewage treatment plant as an object,the effects of ultrasonic time and sound energy density on the dehydration function of sludge were studied firstly,then the internal mechanism of improvement of sludge dehydration function by ultrasonic was discussed.[Result] As the increase of ultrasonic time,sludge particles became smaller,and COD of sludge filtrate went up obviously;meanwhile,the capillary suction time (CST) of sludge increased firstly and then decreased,and the minimum value (75.7 s) appeared when ultrasonic time was 8 s.With the raising of sound energy density,the size of sludge particles went down gradually.However,long ultrasonic time and high sound energy density could decrease the dehydration function of sludge.For the possible mechanism of improvement of sludge dehydration function by ultrasonic,ultrasonic adjusted and regrouped sludge,and hydration water in the sludge was released.[Conclusion] The study could provide certain theoretical foundation for the industrial application of ultrasonic.展开更多
文摘[Objective] The aim was to study the effects of ultrasonic on the dehydration function of sludge and internal mechanism.[Method] Taking the residual sludge from a municipal domestic sewage treatment plant as an object,the effects of ultrasonic time and sound energy density on the dehydration function of sludge were studied firstly,then the internal mechanism of improvement of sludge dehydration function by ultrasonic was discussed.[Result] As the increase of ultrasonic time,sludge particles became smaller,and COD of sludge filtrate went up obviously;meanwhile,the capillary suction time (CST) of sludge increased firstly and then decreased,and the minimum value (75.7 s) appeared when ultrasonic time was 8 s.With the raising of sound energy density,the size of sludge particles went down gradually.However,long ultrasonic time and high sound energy density could decrease the dehydration function of sludge.For the possible mechanism of improvement of sludge dehydration function by ultrasonic,ultrasonic adjusted and regrouped sludge,and hydration water in the sludge was released.[Conclusion] The study could provide certain theoretical foundation for the industrial application of ultrasonic.
