Japan Power Demonstration Reactor

A brief description of the development of forging components in the Japan Steel Works (JSW) is as follows. JSW supplied the plates for the RPVs in the Japan Power Demonstration Reactor (JPDR) of the Japan Atomic Energy Research Institute (JAERI) in 1961 and the Japan Atomic... 

During the third RCM, scientific visits were made to several facilities at the Tokai and Oarai sites. The most important one from the decommissioning point of view was the JAERI Japan Power Demonstration Reactor (JPDR), which is currently being decommissioned. In addition, visits were made to the JAERI reprocessing facility (JRTF), which it is planned to dismantle, and to waste management facilities. 

THE JAPAN POWER DEMONSTRATION REACTOR DECOMMISSIONING PROGRAM... 

Since the first generation of electricity by the Japan Power Demonstration Reactor (JPDR) in 1963, the utilization of nuclear power has been increasing in Japan. As of the end of September, 1992, 41 nuclear power plants are operating with 33,279 MW electricity generation, and the nuclear power shares almost 27% of nation s electric supplyHowever, some of these nuclear power plants are expected to terminate their duty life in the near future. 

The JPDR is a BWR-type (45 MWt) demonstration reactor. It started to generate electricity for the first time in Japan in October 1963. In 1972 the power was increased to 90 MWt for enhancement of neutron irradiation capability. The JPDR was shut down in March, 1976 due to several problems such as cracking on the nozzle of in-core monitor tubes, the failure of control rod drive mechanism and other complications. Table I shows the major specifications, operation history and radioactive inventory of the JPDR. 

Testing of the power conversion components as an integral system utilizing a nonnuclear heat source is seen as a prerequisite prior to connection to the reactor. The thermodynamic performance of the power conversion system can be demonstrated and verified to full temperature and speed conditions at considerably lower pressures then the plant design pressure. A proposal from Japan utilizes an electrical heater as the primary energy supply. Due to the high efficiency of the power conversion system, an outside power supply of only approximately 10% of the thermal plant rating would be required for a test of this nature. 

This report describes the development and activities on fast reactor in Japan for the period of April 1996 - March 1997. During this period, the 30th duty cycle operation has been started in the Experimental Fast Reactor "Joyo". The cause investigation on the sodium leak incident has completed and the safety examination are being performed in the Prototype Fast Breeder Reactor "Monju". The three years design study since FY1994 on the plant optimization of the Demonstration FBR has been completed by the Japan Atomic Power Company (JAPC). 

As for the demonstration fast breeder reactor (DFBR) of Japan, the Japan Atonaic Power Company (JAPC) conducted conceptual design studies for the past several years, and confirmed the feasibility of top entry loop type reactor concept. Based on results of the design studies, the Federation of Electric Power Companies (FEPC) decided in January 1994 to start construction of the DFBR plant at the beginning of the 2000 s. FEPC also decided the basic specifications of the DFBR plant. 

The prototype FBR MONJU was constructed by former JNC to demonstrate electricity generation by FBRs and build sufficient experience with sodium cooled power plants, aiming at their commercialization in Japan in the future. The technologies gained through these experiences support the base of the 4S design as a sodium cooled reactor. 

Apart from the prototype FBR MONJU, much research and development (R D) has already been performed to complete the design of the Demonstration FBR, sponsored by nine Japanese utilities, Electric Power Development Co., Ltd., and the Japan Atomic Power Company (JAPC). The R D included the development of new types of equipment for sodium cooled reactors such as highly reliable electromagnetic pumps and double-walled tube steam generators with leak detection systems for both sodium and water/steam. This new equipment is considered to become more important for the commercialization of sodium cooled reactors, and the 4S is adopting these technologies in its design. 

The world first modular prototype plant, HTR-PM, consisting of two reactor units of 250 MWth each at 750°C reactor outiet temperature, is being built in China. The operation is expected in 2017. The quest in the current development for the 950°C GTHTR300 reactor in Japan and for the systems in the USA, Korea, and other countries is to demonstrate the technologies of advanced fuels, power conversion, and heat applications that can satisfactorily address the set of Generation IV objectives for safety, economics, waste management, and prohferation resistance. 

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