Abstract: Apparatus for separating one type of particle from a mixture of particle types by dropping the mixture through a free fall zone between two spaced vertical walls of electrostatically charged, vertical cylindrical, spaced, continuously rotating electrodes that are continuously brushed by a plurality of spaced vertical cylindrical continuously rotating brushes.

Abstract: An electrostatic separator for separating or removing materials according to their polarizability which comprises a cylindrical surface having a plurality of closely spaced conductors embedded in an electrical nonconductor with the surface adapted to be rotated about its longitudinal axis in close proximity to the material from which loose particles are to be removed. The cylinder is rotated through successive zones wherein the surface of the cylinder is charged while in close proximity to said material causing the particles to migrate to the surface, then through a zone wherein the surface is oppositely charged so as to repel particles therefrom, and collecting and disposing of the particles removed from the material. This apparatus and method has many applications wherein fibers, dust, contaminants, and the like may be removed from the desired product.

Abstract: An apparatus and method are provided for separating electrically neutral solid materials having different dielectric, shape, density or dipole moment properties by passing a mixture of such materials through a nonuniform electric field generated between an electrically charged arcuate surface and a flat horizontal grounded surface having a receiving end, a discharge end and two lateral edges, said arcuate surface being spaced above said horizontal surface and extending from about said receiving end to about said discharge end and from one of said lateral edges to at least midway between said lateral edges; a means for introducing said solid materials into the electric field near said receiving end and conducting said material through the field to said discharge end; and recovering one type of material from said lateral edge adjacent said arcuate surface and another type of material from said discharge end of the horizontal surface.