Air density system with air recirculation and gyrating bar feeder

Abstract

A air density separation has a vertical air separation chamber that opens downwardly to allow rejected material to fall out the chamber through the open bottom. The air density separator is configured to recirculate the air and entrained fines, and so minimizes emissions and costly air treatment processes. The air separation chamber is connected by a first duct to a cyclone. A fan is positioned adjacent the lower end of the air separation chamber, and draws air through a second duct out of the cyclone for reintroduction into the air chamber. The fan by way of the cyclone draws air through the first duct from the air separation chamber. The fan exhausts into the vertical air separation chamber below the material infeed through a plenum. An oscillating screen composed of bars extends into the separation chamber of the air density separator and is used to disperse material into the separation chamber. The bars are spaced apart to allow air to be drawn up through the bars to separate the light component in the feed material from heavier materials. A tray to which the bars are mounted are caused to oscillate by an eccentric weight which is mounted to the bars and driven to oscillate in a horizontal plane. The tray is suspended by four universal linkages to a support frame, the linkages allowing the tray and attached bars to oscillate.