Apparatus and method for the dry separation of particles

United States Patent Application Publication. An apparatus and method for the dry separation of bulk particulate material, especially coarse particles, is provided. The apparatus comprises a chamber, a screen adjacent the chamber and a fluidising device fluidly connected to the chamber. The screen has a screen surface, a plurality of apertures and an opening larger in size than the aperture. A mixture of the coarse particles and a fine particulate medium is fed into the chamber. The fluidising device directs a fluidising fluid to fluidise a fine particulate medium and create a fluidised bed directed towards the screen. The fine particulate medium and the coarse particles pass from the chamber through the openings. The fine particulate medium passes back through the apertures to the chamber. Relatively high density coarse particles also pass back through the openings to the chamber. Relatively low density coarse particles are retained on the screen surface. Vibrations may also be used. 17 page PDF. Pub. No.: US 2020/0368783 Al. Pub. Date: Nov. 26, 2020.