Patent ID: 6938776

Claim:
A method of separating a mixture of particles in a liquid that within chosen limits have different physical property values, comprising the steps of: supplying the particles to be separated via a feeder to a separating screen upon which a layer of facilitating particles is disposed, the size of the facilitating particles being too large to fit through openings in the screen; passing the particles to be separated through the layer of facilitating particles and through the openings in the screen; collecting the particles under the screen, a density of the particles to be separated being greater than that of the liquid; providing a repetitive vertical movement between the particles and the liquid, respectively; and passing all the particles to be separated through the layer of facilitating particles and the separating screen, wherein the particles having a physical property value lying near an upper limit will move faster through the layer of facilitating particles and the screen than the particles having a physical property value lying near a lower limit.