| 摘要 |
In a layering system for the formation of pellets in fertiliser production in particular, a series of tables (1) for advance of pellets to be layered are arranged in a stacked or tiered array, one above the other. Advance of pellets along the tables (1) takes place by fluidisation using air introduced into the bed of pellets on the table (1) from an air duct (4) through the perforated surface of the table. At a discharge end (6) of the table (1), the pellets flow downwardly over a plate member (11) to an edge or lip (12), from where they fall through a layering zone through the input end (5) of the next table downwards in the stack. Pellets pass through the layering zone in freefall, under the influence of gravity. During their passage through the layering zone (15), the pellets are sprayed with a melt, solution or slurry material discharged through nozzles (27) from a supply line (26). As the pellets descend through successives layering zones (15), each associated with a stage of the stacked system, the pellet size increases towards a required final dimension in the terminal stage of the system. |
