Abstract:

Anaerobic digestion is a very slow process with a long retention time，since the hydrolysis is the main rate-limiting step. In order to solve this problem，ultrasound was utilized to promote the anaerobic digestion process by disrupting sludge flocs and microbial cell walls. Results showed that ultrasound treatment could obviously improve the anaerobic biodegradability of sludge，and the hydromechanical shear force produced by ultrasonic cavitations was responsible for sludge disintegration.