Nuclear Fuel Cycle Options

Abstract

In the once-through (OT)-cycle the valuable uranium and plutonium as well as some of the minor actinides are not re-used. The spent fuel-after unloading from the reactor and being stored for about 50 years in intermediate storage facilities-is conditioned for permanent storage and then intended to be disposed in a deep geological repository. In a closed fuel cycle the spent fuel, after its radioactivity has decayed to a certain level in intermediate storage facilities, is shipped to a reprocessing plant. After chemical or pyrochemical reprocessing the fissile plutonium as well as the residual uranium are re-used to fabricate new fuel elements. The plutonium and uranium are recycled in converter and breeder reactors. Recycling is possible both in the U-238/Pu and the Th/U-233 fuel cycles. It is shown that plutonium can be recycled at least three times or even more in light water burner reactors over a time period of about 75-90 years, thereby burning about 50% of the self generated plutonium. After this time period the plutonium can be loaded into the cores of fast breeder reactors for further recycling. Different thermal converter reactor types operating in either the U-238/Pu or Th/U-233 fuel cycle are compared with regard to their natural uranium consumption and separative work requirement for fuel enrichment. For fast breeder reactors operating in U-238/Pu or Th/U-233 fuel cycle also the net fissile material gain (Plutonium or U-233) and the consumption in U-238 and thorium are given. © Springer-Verlag Berlin Heidelberg 2012.