Euradwaste '08 - EU Bookshop - Europa

(only U and Pu) and there are a small number of transmutation systems dedicated to the minor actinides
plus any remaining Pu. Another important element is the combination of systems with fast
and thermal neutron spectrum and the selection for the TRU or minor actinide transmutation of
critical reactors or subcritical ADS. Finally there is also discussion about the homogeneous transmutation
of minor actinides within the reactors fuels or their “heterogeneous” loading in specific
transmutation targets (H2). Although not shown in this scheme the selection of the fuel nature and
the reactor, recycling, and fuel fabrication technologies have also important influence on the scenario
feasibility and performance.
Figure 1: Advanced fuel cycle scenarios from [13], including Light water reactors, LWR, fast critical
reactors, FR, and accelerator driven subcritical systems, ADS. The figure indicates the flows of
Plutonium, Pu, Uranium, U, transuranic elements (Np, Pu, Am, Cm,…), TRU, minor actinides (Np,
Am, Cm, …), M.A., or all the actinides (TRU+U), An.
4. Partitioning and Transmutation expected performance
The potential benefits of the P&T technologies depends first of all on the capacity of the different
technologies and scenarios to reduce the inventories of critical components of the final high level
wastes as compared with the spent fuel of the open cycle. This performance was studied in detail at
[13] for the eight different fuel cycles described in Figure 1, and with particular attention to the advantages
or difficulties of using different types of fast spectrum systems, fast critical reactors, FR,
and Accelerator Driven Subcritical systems, ADS.
In the corresponding NEA/OCDE expert group was agreed, by consensus, that the principle of sustainable
development requires the fuel cycle of future nuclear energy systems to be closed for plutonium
as well as minor actinides, in order to ensure the production of fission energy with limited
amounts of natural resources (i.e. uranium) and long-lived radioactive waste. It also requires a safe
and cost-effective nuclear energy production. The resource efficiency and waste reduction goals
together can ultimately only be reached by the introduction of advanced reactor systems with a sig-
129