Fluidized bed particulate material treating apparatus

A particulate material treating apparatus comprising

• an elongated treating chamber through which a continuous bed of particulate material is caused to traverse from an inlet end to a discharge end along a horizontal path, said chamber including a bedplate disposed in a substantially horizontal plane and having an upwardly facing top surface for support of particulate material thereabove during its traversing movement thereover and a downwardly facing bottom surface, said bedplate having a plurality of apertures formed therein through which gaseous fluid is caused to flow and pass upwardly through the bed of particulate material traversing over said bedplate, said apertures having an entrance end lying in the plane of said bedplate's bottom surface, an exit end lying in the plane of said bedplate's top surface and an axial wall surface extending between and interconnecting said entrance and exit ends, a substantial proportion of said apertures having the wall surfaces thereof configured in a generally frusto-conical shape and divergent in a direction away from said exit end at an angle in the range of 25 to 45 degrees with respect to the longitudinal axis of a respective aperture with the apertures having divergent wall surfaces being disposed in substantially uniformly distributed relationship over the apertured area of said sheet-form plate, said bedplate being of a predetermined minimum thickness whereby said apertures with the divergent wall surfaces produce a controlling effect on the flow path of gaseous fluid exiting from those apertures to cause at least a portion of the gaseous fluid exiting therefrom to initially flow along paths laterally divergent to the aperture's longitudinal axis and passing through a bed of particulate material traversing over said bedplate thereby producing dispersion of the gaseous fluid in a generally upward direction along random flow paths through the bed of particulate material for causing substantially uniform levitation and agitation of the particulate material, and
• a gaseous fluid source coupled with said treating chamber operable to effect a flow of gaseous fluid through said apertures at a rate of flow effecting levitation and agitation of the particulate material traversing over said bedplate and thereby fluidizing the bed of particulate material, the gaseous fluid provided by said source having characteristics to effect treatment of the particulate material.