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US 4,231,227 AGranted
Prill tower rake
AssigneeW. R. Grace & Co.
InventorsRobert M. Stewart, Robert W. Schwartz
Life of this patent
Estimating the term…
Abstract
Apparatus and method for cooling and collecting prills at the bottom of a prill tower including a fluidized prill bed and a rake rotatable therethrough.
Claims1
The process of cooling and collecting urea prills that have fallen through a circular prilling tower without subsequently passing them through a separate cooler which comprises collecting said prills on a flat, substantially circular fluidized bed of prills about one inch thick fluidized by ambient air at about 0.degree. to 120.degree. F. whereby the prills are cooled to about 100.degree. to 140.degree. F.;
- rotating a multi-bladed rake through the bed to further mix the prills and to sweep them toward a collection exit;
- and collecting the thus cooled prills.
Dependencies are inferred from the claim text.