TRU recycling in thorium based PWR fuel was studied recently [Todosow M. et al., 2002]. The analysis showed that for Th based fuel options equilibrium TRU inventory can also be achieved. However, re-enrichment of recovered from the fuel uranium is required to maintain constant fuel cycle length.
1.3. Thesis Objectives and Scope The main objective of this thesis is to develop an innovative fuel cycle for Light Water Reactors (LWRs) featuring the lowest possible impact on the environment from the radioactive constituents in a spent nuclear fuel. The current analysis attempts to evaluate the potential of LWRs to manage the radioactive waste they produce in a sustainable mode. The technical feasibility of such an operation mode would offer more affordable solution to the once through fuel cycle problems due to the possible utilization of the existing reactors and technologies. A major constraint on this study, therefore, is complete compatibility of the sustainable fuel cycle with the current generation of LWRs. Namely, all reactor core operation and safety characteristics must remain comparable to those of the reactor operating on a conventional once through fuel cycle. The present effort examines two major fuel cycle strategies that can be applied to the existing fleet of LWRs without an immediate requirement to develop additional transmutation system technologies such as advanced fast reactors or ADS. The fuel cycle strategies studied are -
once through burndown of TRU in LWR systems alone but with several alternative fuel types
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TRU multi-recycling scenario based on the most efficient with respect to TRU transmutation potential fuel option
The additional goals of this thesis as they are addressed in the following chapters are -
to identify the fuel form which is most effective for transmutation of TRU in LWRs and at the same time allows one to maintain acceptable reactor safety and operation characteristics
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to evaluate the effect of once trough burndown scenario on the waste performance characteristics in the repository
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