New Nuclear Power Technologies
Introduction:There are many new waste disposal technologies which could prove to be somewhat of a solution to the problem of nuclear waste.
Reprocessing, The Missing Step:Although not a new technology, reprocessing can be part of the solution to nuclear waste. When nuclear power was first developed, it was assumed that spent nuclear fuel would go through a process called reprocessing. In reprocessing, one of the major transuranic wastes, 239Pu, is extracted from the spent fuel rods. This 239Pu (plutonium-239) is fissile and can be reused in power plants. The advantages of this process are somewhat obvious: The volume of waste is lessened and more fuel is created for nuclear reactors. However, as with all things, politics can get in the way. In the US plutonium reprocessing was banned because the recovered 239Pu is weapons grade material. If, after reprocessing, the fuel is stolen, it could be used by anyone to construct a nuclear weapon. As of a few years ago, the ban against reprocessing in the US was lifted, but there are still no operating reprocessing plants in the US because of the heavy regulations and the anti-nuclear sentiment of the general public. There are a few countries which do reprocessing, however. France, for instance, regularly reprocesses its spent fuel.
In a reactor being developed by Argonne National Laboratory in the US, almost 100% of the transuranic nuclear wastes produced through neutron capture can be caused to fission. Generally, the fission products created have shorter half-lives and are not as dangerous. This reactor, dubbed EBR-II, uses liquid sodium as a coolant, which means that the internal reactor temperature is much, much hotter than that of a normal PWR reactor, which uses water as a coolant.
Another advantage of EBR-II is that its fuel is not weapons grade quality. When the transuranic wastes are separated from the other wastes in the spent fuel rods, the resultant mix of isotopes can not be used in a bomb. Thus, the mix can be used as fuel for EBR-II without a chance of it getting stolen by a terrorist group for use in an explosive device.
Breeder reactors "breed" fuel. That is, they are designed to create 239Pu from 238U through neutron capture. This "waste" can then be used as fuel.
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