METHOD FOR SOLUBILIZING SLUDGE USING MULTI-FREQUENCY AND MULTI-STAGE COUNTER-FLOW ULTRASONIC IRRADIATION AND APPARATUS THEREFOR TO DECREASE SIGNIFICANTLY AMOUNT OF SLUDGE GEMERATED FROM WASTEWATER DISPOSAL PLANT

摘要

PURPOSE: To provide a method and apparatus for solubilizing sludge, which are able to significantly decrease amount of sludge generated from wastewater disposal plant by re-treating solubilized solution of wastewater sludge treated by multi-frequency and multi-stage counter-flow ultrasonic radiation at a water-treatment system. CONSTITUTION: In a multi-frequency and multi-stage counter-flow ultrasonic irradiation apparatus (10) comprising an ultrasonic generator consisting of a transducer (2), a booster (3), and a horn (4), the apparatus comprises at least two ultrasonic generators (1,1'), each of which is installed to be stepped up and down with another, an ultrasonic contact part which is combined with a lower end portion of the horn and includes a sludge inlet (21) for allowing sludge to be flown in and a sludge outlet (22) for discharging ultrasonic-treated sludge, a sludge inflow pipe (24) which is installed at the sludge inlet, a sludge outflow pipe which is installed at the sludge outlet, and a connection pipe (25) which communicates an outlet of the lower part of the ultrasonic contact part with an inlet of the upper part of the ultrasonic contact part.