Abstract: A method and apparatus for separating an agglomeration of materials having different densities. The agglomeration of materials is fed to a vessel where separation into constituent parts takes place. The vessel is filled with a liquid having a density lower than the constituent materials, the liquid then being injected under pressure into the bottom of the vessel so that lighter materials are entrained in the subsequent liquid flow to be removed from the vessel while heavier materials collect at the bottom of the vessel. Means are provided at the bottom of the vessel to remove the collected heavier material.

Abstract: Flocculated slime to be cleaned is introduced into the top of a vertically disposed, conical precipitator having at its bottom a discharge orifice. The introduced slime flows downwardly through an apertured plate mounted substantially horizontally in the precipitator. The plate is mechanically vibrated at a frequency in the range 20-100 Hz and an amplitude in the range 0.5-1.5 mm as the slime flows therethrough to liberate impurities mechanically trapped in the slime.