Classifying Process and Apparatus (Patent No: 461284)

Inventor: Brusset, Jean Albert (assignor)

Location: Blairmore

Comments: see above

Description: Jean Albert Brusset, Blairmore, Alberta, Canada. Assignor to McNally Pittsburgh Manufacturia., Corporation, Pittsburg, Kansas, U.S.A. Application July 20. 1944. Serial No. 516,482.
12 Claims.


Claim.—1. The method of separating particles of coal from a mixture thereof with particles of heavy refuse, which comprises forming an, aqueous suspension of finely divided, hard, crystalline limestone substantially free from quartz and from components which tend readily to disintegrate through use and handling into ultra-fine particles, introducing the mixture into a bath of said aqueous suspension of finely divided limestone, adjusting and maintaining the density of the aqueous suspension at such a value that the coal particles float on said bath but the particles of heavy refuse sink therein, and separately removing coal particles and particles of heavy refuse from said bath.

4. The process of separating light particles, intermediate particles and heavy particles from each other in a mixture thereof in the presence of a medium comprising a suspension of finely divided solid particles in liquid, which comprises maintaining a body of the medium at a density to float the light particles and nearly to float the intermediate particles, feeding the mixture to the upper part of said body of suspension medium, removing floated light particles from the surface of the suspension medium, permitting the intermediate and heavy particles to fall by gravity in a downward path through the suspension medium, at a zone in said body of suspension medium intermediate the top and bottom thereof, imparting to the heavy particles only a sidewise step-by-step translational movement to one side of said body of suspension medium while simultaneously permitting the intermediate particles to progress by gravity past such zone of translational movement, segregating heavy particles at said side thereof, and thereafter removing them from said body of suspension medium, diverting the inter- ' mediate particles along a downwardly inclined path toward another side of said body of suspension medium than that to which the heavy particles are moved, and removing intermediate particles from said body of suspension medium at said other side of the latter and at a location below that at which said heavy particles are withdrawn.

8. Apparatus for separating a mixture of solid materials of different specific gravities according to the float-and-sink method involving the use of a suspension medium essentially consisting of a suspension of finely divided solid material in a liquid which suspension medium is maintained at such a density that at least one but not all of the constituents of the mixture sinks therein, which comprises in combination a separating tank containing a body of such suspension medium, means for delivering the mixture to be separated to the upper part of the body of suspension medium a sloping deck mounted within said tank for reciprocation substantially in its own plane, said deck having a stepped upper surface providing spaced shoulders facing the higher end thereof, means mounted in said tank above said deck for diverting sinking particles onto said deck, means for imparting reciprocating motion to said deck, segregating channels associated with the higher and lower ends of said deck to receive materials discharged over said ends, and separate means for withdrawing segregated materials from said segregating channels.

11. A suspending medium for separating coal from a mixture thereof with particles of heavy refuse by the float-and-sink method, said sink-and-float medium being an aqueous suspension, having a specific gravity between 1.30 and about 1.70 of finely divided, hard, crystalline limestone rock having a hardness of about 3, said limestone rock being substantially free from quartz and from components which tend readily to disintegrate through use and handling into ultra-fine particles, practically all of which finely divided limestone Is of a degree of fineness to pass a 48-mesh screen, a large fraction thereof being minus 100-mesh and a minor but substantial part thereof, not exceeding about 25 per cent by weight, being minus 200-mesh in particle size.