RBMK Uranium-Erbium Fuel

The history of the development and adoption of erbium fuel in RBMK is described. Research performed at the end of the 1980s – beginning of 1990s led to the conclusion that the optimal method of decreasing the steam coefficient of reactivity in RBMK is to add a consumable absorber – erbium. Computational and experimental work on the safety validation of the new fuel made it possible to adopt this fuel first in RBMK-1500 and then in RBMK-1000. The use of uranium-erbium fuel in RBMK made it possible to increase reactor safety, provide the requisite conditions for modernizing control rods, reduce the acuteness of the problem of storing spent fuel, and improve the economic indices of the fuel cycle. Considering the heightened interest in the use of erbium as a consumable absorber in VVER and some other reactors, the experience gained in developing and operating uranium-erbium fuel for RBMK could be helpful.