Deep-Burn:makingnuclearwastetransmutationpracticalOriginalResearchArticle

ntheDeep-Burnconcept,destructionofthetransuraniccomponentoflightwaterreactor(LWR)wasteiscarriedoutinoneburn-upcycle,accomplishingthevirtuallycompletedestructionofweapons-usablematerials(Plutonium-239),andupto90%ofalltransuranicwaste,includingtheneartotalityofNeptunium-237(themostmobileactinideintherepositoryenvironment)anditsprecursor,Americium-241. Wastedestructionwouldbeperformedrapidly,withoutmultiplereprocessingofplutonium,thuseliminatingtherisksofrepeatedhandlingofweapons-usablematerialandlimitingthegenerationofsecondarywaste.Thereappearstobenoincentiveincontinuingthedestructionofwastebeyondthislevel. AnessentialfeatureoftheDeep-BurnTransmuteristheuseofceramic-coatedfuelparticlesthatprovideverystrongcontainmentandarehighlyresistanttoirradiation,therebyallowingveryextensivedestructionlevels(“DeepBurn”)intheonepass,usinggas-cooledmodularheliumreactor(MHR)technologydevelopedforhigh-efficiencyenergyproduction.Thefixedmoderator(graphite)andneutronicallytransparentcoolant(helium)provideauniqueneutronenergyspectrumtocauseDeep-Burn,andinherentsafetyfeatures,specifictothedestructionofnuclearwaste,thatarenotfoundinanyotherdesign. Deep-Burntechnologycouldbeavailablefordeploymentinarelativelyshorttime,thuscontributingeffectivelytowasteproblemsolutions.ExtensivemodelingefforthasledtoconceptualDeep-Burndesignsthatcanachievehighwastedestructionlevels(70%incriticalmode,90%inwithasupplementalsubcriticalstep)withintheoperationalenvelopeofcommercialMHRoperation,includinglongrefuelingintervalsandthehighlyefficientproductionofenergy(approximately50%).Totheplantoperator,aDeep-BurnTransmuterwillbeidenticaltoitscommercialreactorcounterpart.