Method and apparatus for reusing green sand

An apparatus for reusing green sand comprising:

• an ultrasonic washer for treating green sand with ultrasonic waves in water, the green sand having been used;
• a separator for separating a mixture that is obtained by the ultrasonic washer to form a suspension and to form residual particles of the sand;
• an apparatus for circulating and making the suspension thicker, which apparatus measures a degree of concentration of the separated suspension, which apparatus returns the suspension to the ultrasonic washer if the degree of concentration that is measured equals, or is below, a predetermined degree of concentration, and which apparatus feeds the suspension to a storage tank for storing the suspension if the degree of concentration that is measured is over the predetermined degree of concentration;
• the storage tank that stores the suspension of which the degree of concentration is over the predetermined degree of concentration;
• and
• a volumetric feeder that feeds the stored suspension by a predetermined amount when the green sand is mulled.