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US 5,290,913 AGranted
Method and apparatus for the heat treatment of material
AssigneeCarrier Vibrating Equipment, Inc.
InventorsMark L. McAllister, Steven J. French
Life of this patent
Estimating the term…
Abstract
A method of crystallizing plastic such as polyethylene terephthlate in the form of small particles comprises the steps of placing the particles in a liquid bath such as water, agitating the bath using jets of hot gas such as steam while simultaneously raising the temperature of the particles to a level at which the plastic crystallizes to a predetermined level of crystallinity. The particles are thereafter separated from the bath and dried.
Claims12
Method for crystallizing plastic particles comprising the steps of
- (a) placing plastic particles to be crystallized in suspension in a liquid bath;
- (b) agitating the liquid bath and suspended plastic particles by injecting a plurality of jets of hot gas into the liquid bath containing the suspended particles;
- (c) raising the temperature of the particles by the hot gas jets while suspended in the in agitated liquid bath to a level sufficient to cause the particles to begin to crystallize and maintaining said temperature level of said particles while suspended in the agitated liquid bath for a time sufficient for said particles to reach a predetermined level of crystallinity;
- (d) separating said crystallized particles from said liquid;
- and
- (e) drying said crystallized particles.
3 more elements
Dependencies are inferred from the claim text.