A pan-shape transuranic burner core with a low sodium void worth

A 1575 MWt transuranic (TRU) burner reactor core with a low sodium void wor th has been developed by devising a pan-shaped active core design. The core consists of two types of fule subassemblies that differ in the height of t he fueled regions. This strategy has allowed an extreme "pancaking" of the inner core region, while the radial dimension increase is limited by placin g longer Fuels in the outer core region. The fuel cycle analysis has been p erformed in the equilibrium cycle, consisting of external feed fuel with re processed typical PWR spent fuel and fissile makeup with recycled TRU eleme nts. The neutronic performance characteristics obtained from the equilibriu m cycle analysis show that it would work safely as well as economically, as measured in terms of burnup reactivity swing, peak power density, Doppler coefficient, TRU burning and sodium void worth. The core has relatively low double power peaks in both the inner and outer cores without enrichment zo ning, and this enables to make an active core volume smaller. The developed TRU burner core has been subjected to an extensive parametric study on the reprocessing schemes. investigations are given for sodium void worth, tran smutation capability, burnup reactivity swing and minor actinide (MA) conte nts. Through this series of study, a variant of the TRU burner core that is aimed at preferentially burning MA has been determined. This MA burner cor e uses U-235 as well as the homogeneously recycled TRU elements. This MA bu rner core consumes 140 kg of MA per year, without penalizing the sodium voi d reactivity observed in the TRU burner core. Finally, the combined introdu ction of developed TRU and MA burner cores shows the functional effectivene ss of reducing PWR discharged TRU inventory. (C) 2000 Elsevier Science Ltd. All rights reserved.