Analysis of Environmental Friendliness of Advanced Nuclear Fuel Cycle in Korea

In order to show that the nuclear energy could be a clean energy, radioactive waste management, especially high level waste has to be successfully managed and also accepted by the public. As discussed, progressed and focused at GEN IV international project, reduction of long lived actinide source term and corresponding toxicity through transmutation process has been recognized as one possible solution to the problem and draw lots of attention these days and active R&D efforts are pursued and progressed worldwidely. Especially, much of interest has been initiated to the accelerator driven system (ADS) for the transmutation of the actinide as a subcritical reactors or combination to fast reactor (FR) to generate energy and transmute the HLW simultaneously in a cleaner and safer ways. This study compare and clarifies the roles and merits of the FR and ADS, which would be expected to be introduced into the future Korean nuclear fuel cycle partly, in view of environmental friendliness especially with the existing nuclear fuel cycle dominated by PWR in Korea. After selecting the most plausible and appropriate reactor strategy scenario, the mass flow balance of active radionuclides from ore to waste for several cases of advanced nuclear fuel cycle (where “advanced nuclear fuel cycle” means the nuclear fuel cycle with FR or ADS) is analyzed by computer code. Advanced nuclear fuel cycle with only FR or ADS, and with both FR and ADS were considered for this analysis. A spread sheet type of code, that compute material flow and some environmental friendliness indices chronologically, was developed and analyzed for the calculation. Some indices for the environmental friendliness (i.e. amount of actinide nuclides, radioactivity and radiotoxicity of them, and uranium resource requirement) for several types of advanced nuclear fuel cycles are analyzed comparing with those of once-through fuel cycle. According to the final results, it confirmed quantitatively that the advanced fuel cycle with FRs and ADSs would be one of the possible alternatives to relieve the burden of HLW waste management because those fuel cycle options might reduce the generation of the transuranic radionuclides by tens to hundreds times less compared to that of once-through fuel cycle. Especially advanced nuclear system combined with FR and ADS shows much better effects compared to not combined system. Resource utilization efficiency is also much upgraded high by the introduction of advanced fuel cycles with a significant high share of fast reactors (i.e. only a half amount of uranium can be consumed in case of introduction of breakeven type FR compared to once-through fuel cycle case.)