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Method and apparatus for the formation of granules of a larger size or mass of a desired range from a feed stock of smaller particles comprising feeding a meltable powdery material to be granulated, or a non-meltable powdery material with a meltable binder to the surface of a rotating spreader means

Method and apparatus for the formation of granules of a larger size or mass of a desired range from a feed stock of smaller particles comprising feeding a meltable powdery material to be granulated, or a non-meltable powdery material with a meltable binder to the surface of a rotating spreader means in the form of a disk or bowl, at least a portion of which has been heated to a temperature above the melting point of the meltable component of the feed material wherein the rate of feeding, the energy input to the spreader means and the rotational speed of the spreader means are controlled so that there is sufficient time for at least a partial melting of the meltable component of the feed material substantially solely by contact with the heated surface of the spreader means, centrifugally spreading the material across the surface of the disk or bowl and dispersing the same from the edge thereof into an atmosphere cooler than the melting temperature to form the granulated product. For certain materials only a part of the powdery feed material is melted forming a liquid film carrying a major portion of substantially unaffected or minimally affected feed material to produce a product comprising individual granules containing a core as the major part of each granule with the original powdery material essentially unchanged maintained in self-sustaining form by a matrix of melted and resolidified particles bonded to each other at their surface.

대표청구항 ▼

CM,1. A process for granulation of a powdery material comprising (a) providing a quantity of a feed material containing a material to be granulated in fine particulate form, which material is capable of being partially or completely melted for a short period of time without deleterious affect, or a

CM,1. A process for granulation of a powdery material comprising (a) providing a quantity of a feed material containing a material to be granulated in fine particulate form, which material is capable of being partially or completely melted for a short period of time without deleterious affect, or a particulate material to be granulated admixed with a particulate, meltable binder; (b) depositing said feed material onto the central portions of the surface of a spreader means at least portions of which are maintained at a temperature at or above the melting point of the meltable component in said feed material, the spreader means having peripheral portions which are spaced from the central portions in normal operation and inclined side portions between the central and peripheral portions thereof; (c) rapidly spreading the feed material substantially radially outwardly by centrifugal force produced by rotating the spreader means about a central axis; (d) providing at least a portion of the feed material with a velocity component in the direction of the surface of the spreader means by said centrifugal force to maintain said portion of the feed material in contact with the heated surface of the spreader means as it moves radially outwardly to melt that portion substantially solely by contact with the heated surface to form a layer of a liquid component from the melted portion of the feed material on the surface of the spreader means; (e) adjusting the rate of feeding of said material, the energy input to the surface of the spreader means, and the rotational speed of the spreader means so that there is sufficient time for at least partial melting of the meltable component of said feed material, but insufficient time to deleteriously affect the material to be granulated; and (f) discharging the material to be granulated including the liquid component from the peripheral portions of the spreader means into an atmosphere cooler than the melting point of the meltable component of the feed material to form granules therefrom in the cooler atmosphere which are larger than the particle size of the feed material.