Ultra Safe Nuclear Corporation

Ut-battelle, Inc.

Logos Technologies LLC

Lance Lewis Snead

Francesco Venneri

Paolo Francesco Venneri

Yutai Katoh

The known fully ceramic microencapsulated fuel (FCM) entrains fission products within a primary encapsulation that is the consolidated within a secondary ultra-high-temperature-ceramic of Silicon Carbide (SiC). In this way the potential for fission product release to the environment is significantly limited. In order to extend the performance of this fuel to higher temperature and more aggressive coolant environments, such as the hot-hydrogen of proposed nuclear rockets, a zirconium carbide matrix version of the FCM fuel has been invented. In addition to the novel nature to this very high temperature fuel, the ability to form these fragile TRISO microencapsulations within fully dense ZrC represent a significant achievement.

Processing ultra high temperature zirconium carbide microencapsulated nuclear fuel

A composite moderator medium for nuclear reactor systems and a method of fabricating a composite moderator block formed of the composite moderator medium. The composite moderator medium includes two or more moderators, such as a low moderating material and a high moderating material. The high moderating material has a higher neutron slowing down power compared to the low moderating material. The low moderating material includes a moderating matrix of silicon carbide or magnesium oxide. The high moderating material is dispersed within the moderating matrix and includes beryllium, boron, or a compound thereof. The high moderating material is encapsulated within the low moderating material such that the high moderating material is not exposed outside of the low moderating material. The method can include selecting a sintering aid and a weight percent of the sintering aid in a composite moderator mixture based on the low moderating material and spark plasma sintering.

Composite moderator for nuclear reactor systems

Currently, the commercial fuel of choice, UO-zircaloy, is economical due to an established and simple fabrication process. However, the alternatives to the UO-zircaloy that may improve on system safety are sought. The fully ceramic microencapsulated (FCM) fuel system that is potentially inherently safe fuel and is an improvement on the UO-zircaloy system is prohibitively expensive because of the known methods to produce it. Disclosed herein is a new production route and fixturing that produces identical or superior FCM fuel consistent with mass production by providing a plurality of tristructural-isotropic fuel particles; mixing the plurality of tristructural-isotropic fuel particles with ceramic powder to form a mixture; placing the mixture in a die; and applying a current to the die so as to sinter the mixture by direct current sintering into a fuel element.

Method for fabrication of fully ceramic microencapsulation nuclear fuel

Various embodiments of a nuclear fuel for use in various types of nuclear reactors and/or waste disposal systems are disclosed. One exemplary embodiment of a nuclear fuel may include a fuel element having a plurality of tristructural-isotropic fuel particles embedded in a silicon carbide matrix. An exemplary method of manufacturing a nuclear fuel is also disclosed. The method may include providing a plurality of tristructural-isotropic fuel particles, mixing the plurality of tristructural-isotropic fuel particles with silicon carbide powder to form a precursor mixture, and compacting the precursor mixture at a predetermined pressure and temperature.

Growing community of inventors

Knoxville, TN, United States of America

Lance Lewis Snead