The highly shielded extraction facility MILLI at Kernforschungszentrum Karlsruhe (KFK)

The miniature pilot plant MILLI was designed for experiments on dissolution and extraction of highly irradiated fast breeder fuels. The layout capacity is 1kg fuel per day and per cycle. The facility is in hot operation since 1971 and enables experiments to be performed with highly active material and every plutonium concentration. One dissolver and filter, the first ''co-decontamination'' and the second partitioning cycle are located in two hot cells. The heavy concrete shielding of these cells allows the handling of 300,000-Ci γ-radioactive material with 1-MeV energy in each. The third extraction cycle is contained in a gas-tight glove-box. A description is given of the cells and auxiliary equipment. The extractors used are flat mixer-settlers, critically safe by geometry. The containers are 40-to 50-mm- thick slab-tanks or sandwich tanks. Over a period of five years different experiments with highly active materials have been achieved in MILLI. (author)