A Preliminary Study of Used Fuels in the Conceptual Design of Indonesian Pebble Bed Reactor

A study has been done in investigating some potential engineering issues with the used fuels of Indonesian Pebble Bed Reactor (PBR) conceptual design, the PeLUIt-40. The 40 MWt reactor design is meant to deliver a cogeneration service required in some influential industrial applications. Based on a Monte Carlo simulation using OpenMC, one PeLUIt-40 core may produce only 0.15 SQ of Pu and 0.11 SQ of Leftover U-235 per year. However, since PBR has a significantly low power density, the produced waste is about 36,135 pebbles per year, equals to 7.46 m3 of waste per year. The possible refueling schemes applicable to the reactor are also raising some non-proliferation issues requiring a holistic engineering approach. Increasing the burnup to an attainable fuel discharge burnup may increase the produced Pu quantity, but it may reduce the leftover U-235 and the waste quantities significantly. These impact positively not only on the non-proliferation aspect, but also on the waste management one.