Development of sludge recovery system from the enriched U dissolver

It is known that the dissolver solution contains crud from the fuel assembly, nonsoluble fission product residues composed of molybdenum, ruthenium, rhodium, and palladium, and zircaloy particles of the zircaloy- clad tudes. Accumlation of nonsoluble residues, called sludge, in the dissolver causes partial clogging of the air purge tube for measuring of liquid level and density, clogging of the steam jet ejector on the transfer line to the buffer vessel from the dissolver, and many other problems. Therefore accumlated sludge in the dissolver must be removed periodically. A system to remove sludge from the dissolver was developed, based on the vacuum cleaner. The sludge recovery system removed a large amount of sludge from the dissolvers. The sludge recovery system would remove sludge from similar vessels in hot cells. (author)