Nuclear power breeder reactors

Prospects in the United States for deploying breeders on a large scale were bright when it was beHeved that rich uranium ore would be quickly exhausted as use of nuclear power expanded. The expected demand for uranium was not realized, however. Moreover, the utiliza tion of breeders requires reprocessing (39). In 1979 a ban was placed on reprocessing in the United States. A dampening effect on development of that part of the fuel cycle for breeder reactors resulted. The CRFBP was canceled and France and Japan became leaders in breeder development. 

Fig. 11. Reactor core of MONJU, the Japanese fast-breeder reactor. Courtesy of Power Reactor and Nuclear Fuel Development Corp.

One of the many problems of nuclear power is the availability of fuel uranium-235 reserves are only about 0.7% those of the nonfissile uranium-238, and the separation of the isotopes is costly (Section 17.12). One solution is to synthesize fissile nuclides from other elements. In a breeder reactor, a reactor that is used to create nuclear fuel, the neutrons are not moderated. Their high speeds result in... 

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. 

Y. S. Tang. Ph.D has more than 35 years of experience in the field of thermal and fluid flow. His research interests have covered aspects of thermal hydraulics that are related to conventional and nonconventional power generation systems, with an emphasis on nuclear reactor design and analysis that focuses on liquld-meta -cooled reactors. Dr. Tang is co-author of Radioactive Waste Management published by Taylor 8 Francis, and Thermal Analysis of Liquid Metal Fast Breeder Reactors, He received a B5. from National Central University In China and an MS. in mechanical engineering from the University of Wisconsin. He earned his Ph.D. 

Nuclear power produces spent fuel that contains radionuclides that will emit radiation for hundreds and thousands of years. At present, they are being stored underground indefinitely in heavy, shock-proof containers. These containers could be stolen or may corrode with time, or leak as a result of earthquakes and tremors. Transportation and reprocessing accidents could cause environmental contamination. One solution is for the United States to go to breeder reactors, as has been done in other countries, to reduce the level and amount of radioactive waste. 

Along with these power plants, the U.S. could build up a fuel reprocessing capability to allow spent nuclear fuel to be reused which would lower fuel cost and eliminate the storage of high-level nuclear waste. Fuel for the reactors has been estimated to be available for 1,000 years using standard reactors with high breeding ratios and breeder reactors where more fuel is produced than consumed. 

Conventional nuclear reactors and advanced breeder reactors were America s primary energy strategy since the 1950s to resolve the fossil fuel problem but when a reactor accident occurred in 1979 at Three Mile Island in Pennsylvania, public and investor confidence in nuclear fission dropped. The accident was triggered by the failure of a feedwater pump that supplied water to the steam generators. The backup feedwater pumps were not connected to the system as required, which caused the reactor to heat up. The safety valve then failed to act which allowed a radioactive water and gas leak. This was the worst nuclear power accident in the U.S., but in this accident no one was killed and no one was directly injured. At Three Mile Island faulty instrumentation gave incorrect readings for the... 

In the light of the projected growth of demand for energy services, particularly electricity, there is a renewed interest in the extension of nuclear power in some countries. With uranium being a finite resource as well, Chapter 4 focuses primarily on the question of a future expansion of nuclear power in the context of the availability of nuclear fuels. Moreover, the evolution of the next generation of nuclear reactors, such as breeder reactors or reactors suitable for hydrogen production, is addressed. 

The production of 10 TW of nuclear power with the available nuclear fission technology will require the construction of a new 1 GWe nuclear fission plant every day for the next 50 years. If this level of deployment would be reached, the known terrestrial uranium resources will be depleted in 10 years [3], Breeder reactor technology should be developed and used. Fusion nuclear power could give an inexhaustible energy source, but currently no exploitable fusion technology is available and the related technological issues are extremely hard to solve. 

Since plutonium is the actinide generating most concern at the moment this review will be concerned primarily with this element. However, in the event of the fast breeder reactors being introduced the behaviour of americium and curium will be emphasised. As neptunium is of no major concern in comparison to plutonium there has been little research conducted on its behaviour in the biosphere. This review will not discuss the behaviour of berkelium, californium, einsteinium, fermium, mendelevium, nobelium and lawrencium which are of no concern in the nuclear power programme although some of these actinides may be used in nuclear powered pacemakers. Occasionally other actinides, and some lanthanides, are referred to but merely to illustrate a particular fact of the actinides with greater clarity. 

The most common use of uranium is to convert the rare isotope U-235, which is naturally fissionable, into plutonium through neutron capture. Plutonium, through controlled fission, is used in nuclear reactors to produce energy, heat, and electricity. Breeder reactors convert the more abundant, but nonfissionable, uranium-238 into the more useful and fissionable plutonium-239, which can be used for the generation of electricity in nuclear power plants or to make nuclear weapons. 

One can consider other energy options. For example, to supply 40 to 60 Terawatts of energy via nuclear fission is possible, it could be done. However it necessitates increasing by almost a factor of x500 the number of nuclear power plants ever built. The consequence of such demand is that we would soon deplete earth s uranium supplies. Breeder reactors are an un-stable possibility, like mixing matches, children, and gasoline. Depending upon ones viewpoint fusion remains either a to be hoped for miracle, or an expensive civil-works project. 

Nuclear power is a relatively new source of energy. The first electrical power production from a nuclear reactor occurred on 20 December, 1951, in Idaho at the Experimental Breeder Reactor Number 1 (EBR-1), and since that time nuclear science and technology have had a tremendous impact on the 20th century (Ewing... 

The Experimental Breeder Reactor EBR-1 was the first power reactor and the first fast neutron reactor. It was put in service in 1951 on the site of Idaho in the United-States and it became the world s first electricity-generating nuclear power plant when it produced sufficient electricity to illuminate four 200-watt light bulbs. 

Shortages of oil and coal will be followed by one of uranium. The nuclear industry knows that the fuel of today s thermal nuclear reactors (U235) is exhaustible and therefore in a few decades they plan to shift to breeder reactors. They say little to the public, except that this conversion would make nuclear power inexhaustible. This is true, because the conventional "slow neutron" thermal reactors are "once through" (in the sense that they consume their uranium fuel), while fast neutron breeder reactors make more fuel than they use. 

I have devoted more space to explaining the dangers of nuclear power than to the consequences of using fossil fuels, because while the consequences of carbon emission are well understood, the inexhaustible nature of thermal power and the implications of terrorists using breeder reactor fuel for military purposes are largely unknown. 

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