Light-water breeder reactor

In conclusion, the nuclear properties of thorium can be a source of vast energy production. As demonstrated by the Light Water Breeder Reactor Program, this production can be achieved in nuclear reactors utilizing proven light water reactor technology. 

A light water breeder reactor with MOX fuel has never operated before. Therefore, a prototype plant will be needed before licensing the RMWR in a series... 

CYGRO-3 Bettis Atomic Power Laboratory Light water breeder reactor version of CYGRO, but includes cracking of fuel and fuel-clad friction, which are of interest to LMFBR 1,52, 53... 

The fuel elements are held in position by grid plates in the reactor core. The fuel burnup to which a reactor may be operated is expressed as megawatt-days per kilogram (MWd/kg), where MWd is the thermal output and kg is the total uranium (sum of U-235 and U-238). In light-water power reactors the core may be operated to about 35 MWd/kg (about 3.5% burnup) before fuel elements have to be replaced. In liquid metal fast breeder reactors (LMFBRs) and high temperature helium gas-cooled reactors (HTGRs), the burnups may exceed 100 MWd/kg ( 10% burnup of the heavy metal atoms). 

Oxide fuels have demonstrated very satisfactory high-temperature, dimensional, and radiation stability and chemical compatibility with cladding metals and coolant in light-water reactor service. Under the much more severe conditions in a fast reactor, however, even inert UO2 begins to respond to its environment in a manner that is often detrimental to fuel performance. Uranium dioxide is almost exclusively used in light-water-moderated reactors (LWR). Mixed oxides of uranium and plutonium are used in liquid-metal fast breeder reactors (LMFBR). 

The vast majority (80%) of the reactors mentioned are light-water-moderated reactors (LWR). The LWR subdivide in 60% PWR and 20% BWR. The remaining 20% of the reactors are divided among CANadian Deuterium Uranium reactor (CANDU), Reaktor Bolshoi Moshchnosti Kanalny (RBMK), large power channel reactor, gas-cooled reactor (GCR), advanced gas-cooled reactor (AGR), and fast breeder reactor (FBR). 

The phrase "nuclear power" covers a number of technologies for producing electric power other than by burning a fossil fuel. Nuclear fission in pressurized water-moderated reactors—light water reactors— represents the enrrent teehnology for nuclear power. Down the line are fast breeder reactors. On the distant horizon is nnclear fusion. 

France has the largest implementation of breeder reactors with its 250-MW Phenix reactor and 1200-MW Super-Phenix. The Phenix went into operation in 1973 and the Super-Phenix in 1984. Japan has its 300-MW Monju reactor which was put into service in 1994. While India has the 500-MW PFBR and 13.2-MW FBTR. These reactors produce about 20% more fuel than they consume. Optimum breeding allows about 75% of the energy in natural uranium to be used compared to 1% in a conventional light water reactor. 

LDH LEU LIBD LAW LET LILW LIP LLNL LLW LMA LMFBR LOI LREE L/S LTA LWR Layered double hydroxide Low enriched uranium Laser-induced breakdown detection Low-activity waste Linear energy transfer Low- and intermediate-level nuclear waste Lead-iron phosphate Lawrence Livermore National Laboratory Low-level nuclear waste Law of mass action Liquid-metal-cooled fast-breeder reactor Loss on ignition Light rare earth elements (La-Sm) Liquid-to-solid ratio (leachates) Low-temperature ashing Light water reactor... 

In order, the following types of nuclearfission reactors are described in this section (1) light water reactors, (a) pressurized water reactors, (b) boiling-water reactors (2) high-temperature gas-cooled reactors (3) heavy water reactors and (4) fast breeder reactors. Military reactors are not described. 

After a peak at 2010, the amount of Pu stored is supposed to start decreasing due to the expected increase in MOX fuel fabrication and its usage in Light Water Reactors (LWRs). Obviously, the utilization of MOX fuel by LWRs would gradually reach a balance in which the fissile Pu in the LWR fuel is ca. 5% of the total fuels. Consequently, the utilization of U resources would not be drastically improved. The ultimate utilization will be attained in the Fast Breeder Reactor (FBR) fuel cycle, in which a conversion of fertile 238U to 239Pu overwhelms the consumption of the 239Pu. 

Utilization of plutonium in early research and commercial orders to fabricate thermal recycle and fast breeder fuels did not coincide in timing with Pu availability from different sources. The plutonium comes mainly from high-exposure light-water reactor fuel reprocessing extended storage of this Pu as a nitrate solution leads to 241 contents up to 3%. For hands-on operation with this material it is necessary to reduce the Am content to about 0.5%. It was also necessary to minimize the liquid waste streams from the plant. In designing a technical-scale process, it was... 

Presently, plutonium is used in light-water reactors as MOX fuel and also in small amounts for the development of fast-breeder reactors. Currently 22 power reactors in five countries (France, Germany, Switzerland, Belgium, and Japan) are loaded with MOX fuel and this number is expected to rise to between 36 and 48 by 2000. The use of MOX reduces the inventory of separated plutonium and is regarded as an interim measure before plutonium s possible full-scale use in fast reactors later in the next century. It is known that multiple recycling in light-water reactors degrades plutonium, which in turn limits the number of times it can be recycled to two or three. Such... 

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