Thorium fuel production and results from beginning of life irradiation

An evolutionary, rather than a revolutionary approach to thorium fueled reactors is proposed with an introduction of thorium as the fertile component in mixed oxide fuel for conventional light water reactors. The utility of thorium as a component in today's light water reactors offers improved accident tolerance due to the superior material properties of thorium fuels over conventional uranium fuels. A few notable advantages include better thermal conductivity, higher melting point, higher oxide stability and superior spent fuel characteristics. Consequently, Thor Energy along with a consortium of industrial partners has established a fuel production and irradiation program aimed to license thorium fuels for use in today's light water reactors. Due to the morphology and physical properties of calcined thorium oxide powder, pellet fabrication used for standard uranium oxide fuels must be altered slightly for thorium bearing fuels to yield a product with acceptable theoretical densities, microstructure, and material integrity. At beginning of irradiation life fuel temperature data demonstrates improved fuel characteristics over standard uranium oxide fuel. Fuel centerline operating temperatures are 30–40 K less with a thorium mixed oxide fuel as compared to standard uranium fuel.