A survey on the effect of ultrasonic method on dewatering of bio sludge in wastewater treatment plant

Disintegration and dewatering of produced sludge during wastewater treatment is one of the main challenges in wastewater treatment process. The aim of this study is to investigate the efficiency of ultrasonic method on dewatering of bio sludge in wastewater treatment plant under different conditions and select the best conditions. In the present study, sludge disintegration and sludge dewatering after undergoing different conditions of frequency (35 and 130 KHz) and detention time (3, 5, 10 and 30 min) were investigated and finally the changes of SCOD, CST and SRF were determined. The results illustrated that the maximum ability of dewatering was obtained at a detention time of 5 min and frequency of 35 KHz for ultrasonic. Under this conditions SCOD%, CST and SRF were achieved to 4.3%, 151 S and 2.1×1013 m/kg respectively. According to the results, ultrasonic method significantly increases the sludge disintegration and improves the sludge dewatering.