| 摘要 |
A process and apparatus for the essentially complete recovery of heat, process fluid and yellowcake (U3O8) dust particles normally lost during the drying of yellowcake slurry. The off-gases, consisting of noncondensable gases vaporized fluid, and entrained yellowcake particles, produced in a yellowcake slurry dryer are directed into a condenser in which the off-gases are cooled and condensed by fluid sprays, preferably water. The condensate spent spray fluid and entrained yellowcake particles are collected in the condenser sump. A stream of the condensate and yellowcake particles from the sump is directed into a thickener for the recovery of the yellowcake in the underflow therein and its eventual recombination with the yellowcake slurry being fed to the dryer. A second stream of the spent spray is circulated to the fluid sprays while a third stream is cross-circulated into a bleed chamber. The noncondensable gases and any escaped vaporizable fluid are drawn by a suction means into the bleed chamber wherein any residual yellowcake particles contained in the gases and the escaped vaporized fluid are recovered. The cleaned noncondensable gases are discharged from the bleed chamber into a lixiviant tank containing process fluid and then vented to atmosphere. The heat absorbed by the spray fluid is recovered via an R-11 refrigerant filled heat transfer panel mounted in the condenser. The heat transferred into the panels is rejected from the condenser by use of known heat exchanging means. During operation no external sources of makeup process fluid are required for the operation of the condenser or bleed chamber.
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