Chemistry of inorganic compounds – Phosphorus or compound thereof – Oxygen containing
Reexamination Certificate
2008-05-27
2008-05-27
Langel, Wayne A. (Department: 1793)
Chemistry of inorganic compounds
Phosphorus or compound thereof
Oxygen containing
C423S157200, C423S317000
Reexamination Certificate
active
11818115
ABSTRACT:
A phosphorous pentoxide producing method includes forming a kiln bed using feed agglomerates with a calcium-to-silica mole ratio of less than 1.0 and maintaining a bed temperature at or above 1180° C. along at least 50% of the bed length without exceeding 1380° C. along the entire bed length. Less than 10% of the agglomerates' phosphate input to the kiln remains in the kiln residue as phosphate. Another method includes maintaining a bed temperature at or above 1180° C. along a portion of the bed length and establishing a bed surface-to-volume ratio multiplied by a time for bed heat up to 1180° C. of less than 50 minutes-ft2/ft3.
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Langel Wayne A.
Wells St. John P.S.
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