Abstract
SYNOPSIS: -Recently, it seems that peaceful use of neuclear energy is fairly under way, because light water reactor type power station are increasing and advanced thermal reactors, fast neutron breeding reactors are being developed.
Fuels of these reactors are made of uranium and another fissile materials.
In natural uranium, only about 0.7% U-235 can be fissinable but another 99.3% U-238 cannot.
But U-238 captures thermal neutron in reactor and converts itself into plutonium-239 (Pu-239).
It is called “fuel reprocessing” to recovery this plutonium from spent fuel, and cyclic utilization of it for fuel is called “neuclear fuel cycle”.
Plutonium is used for fuel for many kind of reactors. For instance, it is used to the substitute of U-235 for low enriched uranium fuel to light water reactors, and it can be used to plutonium-self sustaining to advanced thermal reactors.
Also, plutonium is very important for fuel of fast neutron breeding reactors which is called “perfect reactor.”
It is not too much to say that future prowth of geaceful use of neuclear energy is controlled by utilization of plutonium for neuclear fuel.
