Process for preparing granular urea product
AssigneeToyo Engineering Corporation
InventorsEiji Sakata, Genshi Nishikawa, Haruyuki Morikawa
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Abstract
In a granulating process for preparing granular urea from an aqueous urea solution using a fluidized bed method or a fluidized, spouted bed method, an aqueous urea solution having a urea concentration of 94-98.5 wt % is used and the operational temperature of the fluidized bed is controlled in a range of 110-120° C. to accelerate the drying of a granulated product to thereby give a granular urea product having a moisture content of 0.3 wt % or less.
Claims4
A process for preparing a granular urea product having a moisture content of no more than 0.3 wt. %, comprising the steps of:
- employing a fluidized and spouting bed method in a granulator in which an air-supplying pipe injects air into a granulated product in the granulator to form both a fluidized bed and a spouting bed;
- ejecting an aqueous urea solution having a urea concentration of 94-98.5 wt. % into the granulator from a nozzle arranged at the center of the pipe;
- supplying air for fluidization to the fluidized and spouting bed through a porous plate;
- and
- performing granulation at an operational temperature of from 115-120° C. in the fluidized and spouting bed to accelerate drying of a granulated product.
A process for preparing a granular urea product having a moisture content of no more than 0.3 wt. %, comprising the steps of:
- employing a fluidized and spouting bed method in which an air-supplying pipe injects air which has been preheated by an air heater to a temperature of up to 130° C. into a granulated product in the granulator to form both a fluidized bed and a spouting bed;
- ejecting an aqueous urea solution having a urea concentration of 94-98.5 wt. % into the granulator from a nozzle arranged at the center of the pipe;
- supplying air for fluidization to the fluidized and spouting bed through a porous plate;
- and
- performing granulation at an operational temperature of from 115-120° C. in the fluidized and spouting bed to accelerate drying of a granulated product.
Dependencies are inferred from the claim text.