Nuclear plant exposure reduction method, fuel assembly and nuclear power plant

摘要

PROBLEM TO BE SOLVED: To provide a method for reducing radiation exposure in a nuclear power plant which can further reduce radiation exposure, even when the degree of burnup of fuel assemblies is further increased.SOLUTION: A BWR plant 1 includes: a reactor pressure vessel 3; and a core 4 loaded with fuel assemblies 5 arranged in the reactor pressure vessel 3. A downcomer 8 is formed between the reactor pressure vessel 3 and a core shroud surrounding the core 4. A plurality of jet pumps 7 are arranged in the downcomer 8, and a recirculation system pipe 9 communicating with the downcomer 8 is connected to nozzles of the jet pumps 7. A diamond coating is formed on the external surface of each fuel rod included in the fuel assembly 5. Even when clads and the like contained in reactor water are stuck on the surface of the diamond coating, they peel in a short time, thus suppressing activation of the clads.