Abstract: An air distribution plate for incorporation into a material conveyor or a material separator has a plurality of apertured zones alternately arranged along the length of the plate. The apertures in the first series of zones are inclined in the direction of the desired flow of material in the case of the conveyor and in the direction of the desired air flow in the case of the separator and the apertures in the second series of zones incline in the opposite direction by the same amount. Each zone in the second series of zones has fewer apertures than the zones of the first series of zones.

Abstract: An elutriator for separating different grades of leaf material and having a distribution means, an elutriation zone (100) disposed above the distribution means, and a fluid supply fan (113) for supplying a fluid to me zone through the distribution means. The distribution means comprises two distribution plates (10) which diverge in an upward direction, each distribution plate being configured to direct the fluid therethrough in a direction which has a component extending along a surface of the plate. In use, the velocity of air delivered to the elutriation zone is greater than the terminal velocity of at least one grade of the material to be separated.

Abstract: Distribution means for a fluidized bed, comprises a perforated plate (50) having a plurality of apertures. The cross-sectional area of each aperture is in the range of 20.times.10.sup.-6 sq. inches (approximately 130.times.10.sup.-6 sq. cm) to 1000.times.10.sup.-6 sq. inches (approximately 6450.times.10.sup.-6 sq. cm), and the total area of the apertures is in the range of 1% to 4% of the total area of the plate. A fluidized bed-type conditioning apparatus for conditioning material such as tea and tobacco, comprises a conditioning zone disposed above the distribution means, and further comprises means for supplying gaseous medium to said zone through said distribution means.

Abstract: An elutriator (1) for separating different grades of leaf vegetable material comprises an elutriation zone (17) disposed above a flow distributor, and gaseous supply means (13) for supplying a gaseous medium to the elutriation zone (17) through the flow distributor. The flow distributor is adapted to provide a substantially uniform flow of gaseous medium to the elutriation zone (17), and the velocity of air delivered to the zone is greater than the terminal velocity of at least one grade of the material to be separated.

Abstract: Conditioning apparatus for conditioning a leaf vegetable material of a fibrous nature, which apparatus comprises a perforate bed whereby gaseous conditioning medium may be supplied through the perforations to establish a conditioning zone immediately above the bed whereby, in use, the material can be maintained in effectively a fluidized state, the bed being supported in a frame in a manner which permits adjustment of the configuration of the bed relative to the frame at least in a direction of feed of the material to be conditioned.