Problems in the reprocessing of used fuel from nuclear power plants

In the U.S.S.R., the reprocessing of the used fuel from nuclear power stations is recognized as a rational component of the nuclear fuel cycle both economically and technologically. Further, the fuel reprocessing has also the prospect of contributing to the future economy as usable radio-nuclides can be obtained. In the current five year program, the quantity of used fuel to be reprocessed is set for VVER and RBMK. Along with this, fast neutron reactors are also to be introduced, so that the fuel reprocessing for this type of reactors becomes necessary. Up to this day, many experiences have been accumulated in the fuel reprocessing for thermal neutron reactors. The effective process in this case is that of solvent extraction. For fast neutron reactors, on the other hand, not only the wet process but also the dry process has been investigated. However, the former is more readily acceptable, while the latter is evaluated as a future method. (J.P.N.)