A fluidized bed apparatus for separating and sorting solid bodies of different densities. It comprises: a container for the fluidized bed; means for maintaining the bed in a state of fluidization under constant pneumatic pressure; a conveyor whose inner face is adapted for lifting objects out of the bed (lifting conveyor) designed to travel between a lower portion of the bed and the space above it forming an enclosure of substantially rectangular prismatic shape with horizontal and vertical sides, the fluidized bed portion within said enclosure constituting a separation zone whose bottom is formed by the lower horizontal portion of the lifting conveyor; a first output conveyor for the removal of the sink fraction travelling through the space above the bed inside said enclosure and adapted to receive objects dumped by the lifting conveyor; a second output conveyor adapted for the removal of the float fraction; means for mechanically moving the float fraction in the bed out of the separation zone in a direction substantially normal to the direction of horizontal travel of said lifting conveyor; and means for feeding into the separation zone a mixture of objects to be separated.
