MONJU prototype power reactor

The core of the Japanese prototype fast breeder reactor (PBFR) "Monju" from (Power Reactor and Nuclear Fuel Development Corporation 1980]... 

Classification of SNR-300 The nuclear power plant SNR-300 was a prototype reactor project comparable to PHENIX in France, to the Prototype Fast Reactor PFR in Great Britain, and MONJU in Japan. PHENIX and PFR went into operation in 1974, and MONJU reached... 

The experimental FBR "Joyo" and the prototype FBR "Monju" were developed by the Power Reactor and Nuclear Fuel Development Corporation (PNC). 

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). 

On the prototype reactor Monju, the initial criticality was achieved in April 1994 and the start-up tests are in progress. The reactor power has been increased gradually from February 1995. Generation of electric power and connection to the grid will be started in July 1995. 

France in particular has operational experience with a commercial scale fast reactor, Snperphenix, with 1,300 MWe power ontpnt. In Germany, although a steam-cooled fast reactor had been considered, they have actually developed SFRs, beginning with the experimental reactors, KNK-I and II. Then, a prototype reactor, SNR-300, with 327 MWe power ontpnt was constmcted. It had the same plant concept as the prototype reactor Monju in Japan. However, the provincial government where SNR was constmcted opposed its operation in 1986, and it was dismantled. 

The prototype fast breeder reactor "Monju was constructed in 1990. The output operation had been carried out and preparations for the full-power operation were being made (O Fig. 58.13). However, it caused sodium leaks from the secondary system on December 8, 1995 and the operation has heen suspended. As of 2009, the overall plant and its functions, including long-stopped as well as improved facilities, have been checked, and preparations to restart operation are under way. 

The prototype reactor MONJU of 280 MW(e) power was stopped temporarily due to a leak in the non-radioactive secondary heat transport system, that occurred in December 1995 during the 40% power pre-operational testing phase. 

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. 

Design features Compared with the experimental reactor Joyo, the prototype reactor Monju has about seven times the thermal capacity - (Joyo 100 MWt Monju 714 MWt - and a provision for power generation. 

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