Required Energy Reduction for Treatment of Excess Activated Sludge using Ultrasonic Vibration

Abstract

The goal of this study is to enhance secession ability of adsorbed water in the fine particles of sludge from waste treatment plant using ultrasonic wave energy. Results of the treatment involving reduction in the final sludge cake affect the usage of energy required for sludge combustion. Excess activated sludge before dewatering process was sampled in the local area and the test conditions included application time and power of the ultrasonic energy and types of flocculants to investigate the dewatering behaviors. Capillary suction time(CST) and viscosity of the tested sample were the main indicator for the dewaterbility of the treated sludge. The results of the study show that the ultrasonic treatment decreases the dewaterbility of sludge sample significantly. The degree of the effectiveness, however, varies with the test conditions. Energy and cost reduction caused by the ultrasonic treatment are also discussed in detail.

Modification of Activated Sludge Cohesion by Enzymatic Catalysis Process and Perspectives

“…Clearly these two ways of remediation are (or may be) related to sludge cohesion. Some chemical [4] or physical [8] processes could be aligned in this concept and do not necessarily use cheaper or safer processes for the environment (as some flocculants). The use of enzymes as clarifier's stabilizers against hydraulic shocks but also as cofactors in sludge treatment appears as a realistic perspective, after an optimization period of the process both in the hydrodynamic field and from the perspective of treatment and recovery of sewage sludge application [9][10][11][12].…”