Event Timeslots (1)

Day 2 – June 21
The UK has a substantial inventory of separated plutonium from its historical reprocessing of spent nuclear fuel. The Government’s preferred option for this is re-use as a Mixed uranium-plutonium OXide (MOX) fuel. However, 5% is not suitable for re-use and is recommended for disposal in a Geological Disposal Facility (GDF) after having first been immobilised in a ceramic wasteform. The NDA is evaluating processes for plutonium immobilisation. One option being considered is ‘Disposal MOX’ which is the manufacture of regular MOX but intended for disposal to GDF not irradiation. Regular MOX is manufactured by heterogeneous blending of uranium and plutonium feed powders and then forming fuel pellets through a technologically-mature cold-press and sinter process, yielding a heterogenous MOX product. For Disposal MOX production this may be modified by increasing the plutonium loading and introducing neutron poisons into the material for criticality safety/safeguards purposes. Alternatively, advanced manufacturing technologies such as Flash and Spark Plasma Sintering may provide routes to higher quality, denser Disposal MOX. Thus, using plutonium simulants, this project will explore using modifications to existing manufacturing routes and advanced manufacturing technologies described above in the development of a Disposal MOX, underpinning HMG’s policy on the direct disposal of plutonium.