Checkerboard Fuelling - The Key to Advanced Fuel Cycles in Existing CANDU Reactors

Abstract

A fuelling scheme has been developed that makes possible a significant increase in the initial enrichment and hence exit burnup of the fuel that can be used in existing CANDU reactors. No hardware changes to the reactor are required. Sufficient flux and power shaping, especially along the fuel channel, can be achieved with the scheme to improve the worth of the reactivity devices in the presence of enriched fuel. Mixed oxide fuel with a fissile content of 1.27 weight-percent gives exit burnups of 22000 MW.d/t(HE) resulting in a 40 percent reduction in uranium requirements and reduction in fuelling machine usage. Existing


CANDU reactors can then be adopted to more uranium conserving cycles when economic conditions favour their introduction. They can also be adopted to Low Enriched Uranium (LEU) cycles which are currently competitive.