A Monitor for Characterization of Leached Hulls and Dissolver Sludges

In reprocessing plants leached hulls and dissolver sluges represent rather important intermediate level a-waste streams. Control of the dissolution process requires monitoring of leached hulls.For plant safety monitoring of the dissolver sludges could become important, A first characterization of hulls and dissolver sludges in terms of Plutonium content and total neutron emission was done using a simple nondestructive measurement system based on active and passive neutron counting. This system, allows the detection of the following minimum quantities of Plutonium: 1,1 g Pu homogeneously distributed in dissolver basket of diameter up to 30 cm and 0.4 g Pu in the dissolver sludge. The figures correspond to the following amount of residual fuel in percent of total fuel: hulls 0.06%; sludge 0.03%.