Nuclear Fuel Cycle
[ Nuclear Power Generation ]

Nuclear fuel cycle represents the series of industrial processes of nuclear fuel from mining to reprocessing.
Uranium, used as a fuel for nuclear power generation, is extracted from uranium mines, processed into fuel assemblies, and placed in nuclear reactors. Spent nuclear fuel that has reached the end of its useful life, still contain resources such as uranium and plutonium, produced while the uranium was generating power. These resources can be recovered and reprocessed into fresh fuel, to help ensure long-term stable energy supply. The nuclear fuel cycle for a light water reactor is shown below.

The nuclear fuel cycle for a light water reactor

Nuclear Fuel Cycle
Source: Japan Atomic Energy Relations Organization

MHI is actively participating in nuclear fuel cycle development projects below, led by the state and Japan Nuclear Fuel Ltd. (JNFL), to contribute to the development of Japan’s energy security.

1) Uranium Enrichment

MHI is engaged in the construction of JNFL’s Rokkasho uranium enrichment plant and is contributing to establishing Japan’s uranium enrichment technology through centrifuge separation method.

2) Spent Fuel Reprocessing

The establishment of a spent fuel reprocessing technology will be a key factor in completing Japan’s nuclear fuel cycle. We are steadily moving ahead with the construction of JNFL’s Rokkasho reprocessing plant and developing next-generation reprocessing technology for the fast breeder reactor fuel cycle.

3) Fuel Transportation / Storage

MHI has been developing safe, reliable and economical fuel transportation casks for the transportation of new / spent fuels and the intermediate storage of spent fuels.

4) Geological Disposal

MHI is conducting research and development for the safe geological disposal of high-level radioactive wastes (vitrified wastes) separated through the reprocessing of spent fuel.

Fuel Supply

1) Design

Utilizing its state-of-the-art systems, MHI Group provides reliable nuclear fuel products, developed as an integral part of the design of nuclear power plants.

Core Design:
MHI Group provides core management techniques to safely and efficiently use the nuclear fuels, from the basic design of new plants to the detailed design of replacement core for every cycle in existing plants. We also provide a wide variety of services such as advanced core management/operation support using online monitoring systems.
Improvement of fuel performance:
We are working on developing high burn-up fuel (55Gwd/t) to extend the fuel loading period, as well as even higher-performance fuel.

2) Manufacturing

Within MHI Group, Mitsubishi Heavy Industries, Ltd. is responsible for the designs of fuels and the nuclear core, and Mitsubishi Nuclear Fuel Co., Ltd. (MNF) is in charge of manufacturing the nuclear fuel. MNF has extensive experience in producing nuclear fuel, being the only company in Japan that can handle the entire flow including reconversion processing and fabrication of fuel assemblies. To ensure the utmost quality, we maintain a stringent quality assurance system in every manufacturing process, involving detailed inspections utilizing our state-of-the-art technology.

3) R&D

Partnering with domestic and overseas research institutions and manufacturers, MHI Group engages in a broad spectrum of R&D related to power plants, from basic materials research to applied technology research. In addition to the MHI Takasago R&D Center, we engage in specialized research on nuclear fuel, fuel cycle, and reactor materials in the hot-lab facilities of Nuclear Development Corporation (NDC) in Tokai-mura, Ibaraki prefecture, to further improve the reliability and performances of our nuclear products.

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