Mobile mineral preparation plant

Apparatus for separating granular material composed of particles of different specific gravity, comprising:

• a frame defining a receiving chute and a discharge chute;
• at least four water-containing hydraulic separation cells serially supported on said frame and including an upstream cell operatively associated with said receiving chute and a downstream cell operatively associated with said discharge chute, each cell including:
• a wave chamber with a horizontal screen located below the water surface and adapted to support submerged granular material in a slurry;
• a refuse bin separated from said wave chamber for receiving refuse in the form of particles of relatively high specific gravity;
• means for removing refuse from said bin;
• and
• plunger means for cyclically raising and lowering the water level in said wave chamber to cause horizontal separation of particles of different specific gravity, the stroke of the plunger means for each cell being of progressively decreasing magnitude from said upstream cell to said downstream cell;
• each plunger means being in opposite phase with any adjacent plunger means so that when the water level in one wave chamber is at its highest level, the water level in any adjacent wave chamber is at its lowest level;
• said wave chambers of said cells defining a slurry-filled flow channel extending from said receiving chute to said discharge chute;
• whereby said plunger means for said cells generate an oscillating wave that progresses along said flow channel and that has at least two full wave cycles produced therin from said upstream cell to said downstream cell, said wave being reinforced by the plunger means for each successive cell and having a controlled decreasing amplitude from the upstream end to the downstream end of said flow channel so that the wave oscillations at the terminal end of the flow channel are sufficiently small to enable a fine discrimination between a lighter material to be conveyed to the discharge chute and a material relatively close in specific gravity to the lighter material, to be separated from the lighter material.