One new fuel breeding configuration for long cycle life fast spectrum reactors

Abstract Nuclear energy is a type of carbon free energy to revent global warming and as a baseload energy source, but the rare uranium sources seriously limit the development of nuclear energy. The world’s total depleted uranium stock is evaluated to be about 1.2 million tons in 2001, and the annual increment is approximately 57,000 tons. One of ways is converted fertile materials into fissile materials, the fast neutron spectrum reactors have the function of breed fuel. There are two basic fuel configuration, external breeding concept or internal breeding concept. In this study, a novel fuel breeding configuration, depleted uranium fueled blanket material and enriched uranium loading into one fuel rod simultaneously, is proposed to enhance the fuel utilization. The evolutions of neutron flux, nuclides density and fuel burnup are shown to reveal the characteristic of new configuration. Two different schemes are demonstrated to be long cycle life, more than 15 effective full power years, 20 effective full power years, respectively. The results illustrate that utilization rate for depleted uranium fueled blanket materials could be as high as 15 % for once through fuel cycle. The distributions of power density versus axial direction were calculate to analyze the safety margin of thermal-hydraulic. Finally, the feedback coefficients of full core loading with scheme B assemblies were evaluated to access the performance of safety.