Impact of Partitioning and Transmutation on High-Level Waste Disposal for the Fast Breeder Reactor Fuel Cycle

Abstract

The impact of partitioning and/or transmutation (PT) technology on high-level waste management was investigated for the equilibrium state of several potential fast breeder reactor (FBR) fuel cycles. Three different fuel cycle scenarios involving PT technology were analyzed: 1) partitioning process only (separation of some fission products), 2) transmutation process only (separation and transmutation of minor actinides), and 3) both partitioning and transmutation processes. The conventional light water reactor (LWR) fuel cycle without PT technology, on which the current repository design is based, was also included for comparison. We focused on the thermal constraints in a geological repository and determined the necessary predisposal storage quantities and time periods (by defining a storage capacity index) for several predefined emplacement configurations through transient thermal analysis. The relation between this storage capacity index and the required repository emplacement area was obtained. We found that the introduction of the FBR fuel cycle without PT can yield a 35% smaller repository per unit electricity generation than the LWR fuel cycle, although the predisposal storage period is prolonged from 50 years for the LWR fuel cycle to 65 years for the FBR fuel cycle without PT. The introduction of the partitioningonly process does not result in a significant reduction of the repository emplacement area from that for the FBR fuel cycle without PT, but the introduction of the transmutation-only process can reduce the emplacement area by a factor of 5 when the storage period is extended from 65 to 95 years. When a coupled partitioning and transmutation system is introduced, the repository emplacement area can be reduced by up to two orders of magnitude by assuming a predisposal storage of 60 years for glass waste and 295 years for calcined waste containing the Sr and Cs fraction. The storage period of 295 years for the calcined waste does not require a large storage capacity because the number of waste packages produced is significantly reduced by a factor of 5 from that of the glass waste package in the FBR fuel cycle without PT.

A Review of Environmental and Economic Implications of Closing the Nuclear Fuel Cycle—Part One: Wastes and Environmental Impacts

“…There is also a general consensus that the reductions in thermal loading achievable with radionuclide separations in a closed cycle enables closer packing of wastes in a repository [17,41,49,66,68,72,73,75]. This can be of utility by requiring a smaller size for the repository footprint, or by emplacing more waste in the same total area; both have the same consequence of more low-carbon nuclear electricity generated per m 2 of repository space.…”

“…The C configuration is for wastes of the lowest heat generation originally designed for compressed waste forms of hulls and end pieces from SNF. Precise details are available in reference [73].…”

“…Table 12. Areas and volumes used by Nishihara et al [73] for different vertical (V) and compact (C) emplacement configurations. Nishihara and coworkers extended their calculations to HLW disposal from an FBR fuel cycle with (a) reprocessing, (b) partitioning of HHR as a separate waste form, (c) MA separation and transmutation, (d) partitioning of HHR and transmutation of MA [73].…”

Study of Minor Actinides Transmutation in PWR MOX Fuel

“…Accordingly, the study of MAs transmutation is a significant work for the postprocessing of spent fuel. The transmutation of MAs is studied in both PWR [3,4], Fast Breeder Reactor (FBR) [5,6,7,8] and subcritical reactors [9,10]. The transmutation of MAs in different reactors has been introduced in Ref.…”

Cesium (Cs) particle formation based on a laser photochemical reaction with a self-injection-seeded Ti:sapphire laser for Cs isotope separation

“…Partitioning and/or transmutation (PT) technology is expected to reduce these radioactive hazards of LLFP [2], and 135 Cs is considered to be one of its effective targets [3,4]. By neutron irradiation, 135 Cs is transmuted to 137 Cs with a lifetime of approximately 30 yr, consequently reducing long-term radiological toxicity.…”