GB456895A - Improvements in or relating to the quantitative and/or qualitative separation of materials in grains or pieces, such as minerals, coals and the like - Google Patents

Abstract

456,895. Separating solid materials. HOYOIS, L., 92, Chaussee de Ransart, Gilly, Belgium. April 12, 1935, No. 11403. [Class 82 (ii)] To separate a desired portion from a mass of granular material, e.g. minerals, coal, &c., a moving bed of the material is formed from which a portion is allowed to separate, the quantity separating from the bed being determined by the provision of adjustable water currents by means of which a predetermined quantity of the separated material is carried away. The separation may be purely quantitative or may be partly qualitative, for example in cases in which stratification occurs in the moving bed of material. Upward or downward currents of water may be produced at the point of separation to assist the qualitative separation. In the form shown a bed of material is carried down a trough A by a stream of liquid introduced at C and a portion separates from the bed and passes through an opening D, the area of which is adjusted by a movable damper G. A weir F is preferably provided on the side of the opening D remote from the feed end of the trough. The separated portion passes into a box E, being preferably confined therein in the form of a hillock by partitions H I. The box E has an adjustable discharge opening O and two water inlets J, K controlled by cocks 1, 2 respectively. By controlling the amount of water introduced into the box any desired hydrostatic head may be produced on the outlet O, this hydrostatic head determining the rate of discharge through the outlet. When a desired hydrostatic head has been established, there can be produced, by varying the amount of water introduced at K relative to that introduced at J, any desired strength of current, varying from zero when the cock 2 is closed to a maximum when the cock 1 is closed, passing from the inlet K to the opening O. This current which is preferably canalized by partitions S and T carries a portion of the separated material to discharge and thereby controls the amount separating from the bed in the trough A. If the hydrostatic head produced is such that it extends to the top of the weir F any desired upward current can be produced in the opening D by increasing the amount of water introduced at K. A downward current through the opening D can be produced by temporarily throttling down either or both of the cocks 1 and 2 to reduce the hydrostatic head.