ApreliminarydesignstudyfortheHYPERsystemOriginalResearchArticle

Inordertotransmutethelong-livedradioactivenuclidessuchastransuranics(TRU),Tc-99,andI-129inLWRspentfuel,apreliminaryconceptualdesignstudyhasbeenperformedforanacceleratordrivensubcriticalreactorsystem,calledHYPER(HYbridPowerExtractionReactor).ThecorehasahybridneutronenergyspectrumwhichincludesfastandthermalneutronsforthetransmutationofTRUandfissionproducts,respectively.TRUareloadedintotheHYPERcoreinaTRU–Zrmetalformbecauseametaltypefuelhasverygoodcompatibilitywiththepyro-chemicalprocesswhichretainstheself-protectionoftransuranicsatalltimes.Ontheotherhand,Tc-99andI-129areloadedaspuretechnetiummetalandsodiumiodide,respectively.Pb–BiischosenasaprimarycoolantbecausePb–Bicanprovideagoodspallationtargetandproduceaveryhardneutronenergyspectrum.Asresults,theHYPERsystemdoesnotneedanyindependentspallationtargetsystem.9Cr–2WVTaisusedasawindowmaterialbecausethisadvancedferritic/martensiticsteelisknowntohaveagoodperformanceinthehighlycorrosiveandradiativeenvironment.ThesupportratiosoftheHYPERsystemareabout4–5forTRU,Tc-99,andI-129.Therefore,aradiologicallycleannuclearpower,i.e.zeronetproductionofTRU,Tc-99andI-129canbeachievedbycombining4–5LWRswithoneHYPERsystem.Inaddition,theHYPERsystem,havinggoodproliferationresistanceandhighnuclearwastetransmutationcapability,isbelievedtoprovideabreakthroughtothespentfuelproblemsthenuclearindustryisfacingwith.