Patent ID: 7347333
Filing Date: 2008-03-25
Classification: B07B

Abstract:
1. Apparatus for air separation of solid materials of different density comprising a fan, a substantially closed space, rigid surfaces within the space, an entrance for admitting solid materials of mixed density into the space, a discharge for emptying relatively high density solid materials from the space, an entry for a high volume of relatively clean air into the space from the fan, an exit for air from the space, the space being arranged to direct solid material from the entrance to the discharge in a free fall state away from rigid surfaces in the space, substantially all of the high volume of air flowing from the entry to the exit passing over and sweeping, in counterflow relation, substantially all of the material being directed to the discharge in a free fall state, an air knife directing air at a velocity substantially greater than the average air velocity of the flow of air from the entry to the exit at the material in a path between the entrance and discharge where said material is in a free fall state whereby relatively low density material is separated from relatively high density material, the combined flow of air from the inlet air and the jet air being sufficient to entrain low density material and carry it through the exit.