Study on the disintegration mechanism of excess sludge under the chemical effect of ultrasonic cavitation
摘要
To investigate the chemical effect of ultrasonic disintegration of excess sludge,bacteria and excess sludge were treated with ultrasonic for 0-40 min,and the content of H2O2 produced during the process was measured. In addition,bacteria and excess sludge were treated with the same amount of H2O2 as produced during the ultrasonic process. The effect of isopropanol on the ultrasonic disintegration of excess sludge was analyzed. The results showed that the content of H2O2 increased continuously after ultrasonic treatment of bacteria and excess sludge,which verified the existence of the chemical effect of ultrasonic cavitation. Both ultrasonic and H2O2 had disintegration effect on bacteria,and multiple effects of ultrasonic cavitation could promote cytoplasmic efflux. By comparing the disintegration rates of ultrasonic and H2O2 on excess sludge,and the reduction rates of nucleic acid and peptidoglycan concentration after ultrasonic and ultrasonic with the addition of isopropanol,it was concluded that the chemical effect of ultrasonic cavitation contributed about 10% to the disintegration of excess sludge.