power operations creates a significant environmental threat. Minor actinides may be reprocessed as a side function in fast oxide-fueled reactors. However, this method is not sufficiently effective. A more efficient method involves burning minor actinides in specialized cores using fuel that does not contain uranium-238. Including fast reactors with such cores in the nuclear power industry’s closed fuel cycle would make it possible to stabilize the accumulation of minor actinides. In such a system all actinides produced by the industry are also recycled by it, and only the portion of these materials that cannot be separated out through chemical reprocessing must be stored as wastes. Organizing such a system, however, requires major capital investments for the creation of a large number of external fuel cycle enterprises. Therefore, the burning of plutonium and minor actinides in the open fuel cycle is of interest.
This report considers various means of using sodium-cooled fast reactors for reprocessing plutonium and minor actinides produced in nuclear power industry operations.
In analyzing the possible use of BN-type fast reactors1 to recycle wastes from the nuclear power industry, let us highlight two problems: reprocessing of plutonium and reprocessing of minor actinides.
Efficient recycling (burning) of plutonium can be carried out in mixed-oxide-fueled fast reactors with reduced internal breeding due to increased fuel enrichment, but the use of mixed oxide (MOX) fuel for these purposes is not the best option. From the standpoint of secondary plutonium output, it would make sense to consider fuel compositions without uranium-238, as this isotope is the source that produces both plutonium and other very environmentally harmful actinides. Fuel without uranium-238, with this isotope being replaced by some inert matrix, is of great interest in this regard. A number of technological laboratories in Russia, France, and Japan have been working recently to develop such a fuel. For example, a power reactor (fast or thermal) could burn approximately 750–850 kg/GW (el) of plutonium per year without producing any secondary plutonium. Burning plutonium in reactors using fuel without uranium-238 is much more efficient in comparison with using MOX fuel.
Another important problem involves the reprocessing of minor actinides. Plutonium may be used as an efficient fuel in thermal and fast reactors for electricity production purposes. Minor actinides cannot be used in thermal reactors for these purposes, and their continual accumulation as a result of nuclear power industry operations creates a significant environmental threat. Let us note once again that plutonium from spent fuel from thermal reactors contains about 7 percent minor actinides, an amount that increases over time as a result of the decay of plutonium-241 (T1/2 = 14.7 years) and its transformation into americium-