– Edited By Chris Reed –
Sumitomo Metal Industries Limited has received the Technical Award from the Information System on Occupational Exposure Committee that is led by the joint secretariat of the OECD Nuclear Energy Agency and International Atomic Energy Agency at the ISOE Asia Symposium.
The Committee awards technologies that serve to reduce radiation exposure of workers at nuclear plants. Sumitomo Metals was awarded for its contribution in reducing radiation level nuclear plant, by supplying its feed water heater tubes that use the awarded filming technology.
Sumitomo Metals has become the first material maker to receive the ISOE Technical Award.
1. Development background and outline
Nuclear power generation has attracted attention globally from the viewpoint of reduction of carbon dioxide emissions and many plants are under construction or being planned in the world. One of the big challenges for widespread, effective utilization of nuclear power generation is to reduce occupational radiation exposure. The ISOE Committee targets to ultimately reduce nuclear power plant workers' radiation level close to the normal exposure level of nature.
Stainless and other steel tubes used in the nuclear power plants tend to release a minute amount of metal ion such as cobalt and chromium in the cooling water of a reactor. The ion tends to increase the amount of exposure, which has caused radiation exposure at the time of maintenance work of the generation plant. Consequently, it has become necessary to inhibit release of such ion for reducing radiation exposure.
Sumitomo Metals has succeeded, for the first time in the world, in manufacturing material which reduces the content of cobalt to a minute amount and developing a film processing technology, by which the oxidized film formed on the inner surface of tubes helps to reduce release of metal ion including cobalt and chromium from tubes.
2. Development outcome
This film processing technology was adopted at the boiling water reactor type of a nuclear power plant, which has attained the world's lowest radiation level and has contributed to workers' radiation exposure.
3. Future development
Sumitomo Metals aims at applying the new film technology for steam generator tubes in the widely used pressurized water reactor type of nuclear power plants, for contributing to reduction in occupational radiation exposure.