Abstract: The invention consists of an upright tank structure that includes axially aligned first and second tank parts, the first tank part being smaller in diameter than the second part. A first horizontal barrier plate having holes therethrough is mounted in the first tank part between upper and lower regions of the same. A second annular barrier having holes therethrough is mounted between the side walls of the first and second tank parts between upper and lower regions. Feed slurry is introduced into the upper region of the first tank part. Water under pressure is introduced into the region below both the first and second barriers and is caused to flow upwardly through the openings of the barriers with the formation of water jets extending upwardly from the openings. In operation the solids of the feed slurry are separated into coarse, fine and intermediate or middling fractions. The invention includes both apparatus and a method of operation.

Abstract: Apparatus and method for the separation of solid particles from hydrous slurries being particles of different settling velocities, such as slurries containing minerals including ore solids, coal and sands. The slurry solids are subjected to the jetting action of water discharged through barrier plate openings to effect separation between particles of greater settling velocity, which progress downwardly through the openings and are discharged in an underflow, and particles of lower velocity that progress upwardly and are discharged in an overflow.

Abstract: A method and apparatus for separating a hydrous slurry into overflow and underflow fractions which have particles differing in settling velocities. When applied to slurries of natural sand the invention provides an overflow containing fine sand particles and an underflow containing coarse sand particles. A barrier is employed having openings through which water flows upwardly with jetting action to provide a separating action in which coarse solids pass downwardly and fine particles progress upwardly. The apparatus is constructed whereby the slurry is introduced tangentially into the space above the barrier to cause continuous swirling movement of the material.