Scale-Up of Calcium Polyphosphate Fibers

Scale-up from laboratory to a modest pilot plant scale was no minor task for preparations of calcium polyphosphate samples of 50 to 100 lb per batch. Containment problems suddenly take on a new complexion. To lose control of 100 lb of molten phosphate at temperatures approaching 1000 °C could cause major prob- 

To minimize the damage that could occur to a furnace and danger to personnel in the event of a spill, the furnace floor was covered with a course sand to absorb as much of a spill as possible. A bed of sand was also maintained at the base of the furnace to trap any spillage, keeping it from flowing. Fortunately, this never became a problem. Several crucibles cracked during their use, but none catastrophically. Since crucibles were intentionally sacrificed upon the completion of crystallization, cracked crucibles presented no significant problems. 

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