Preparation of UO2 Kernel for HTR-10 Fuel Element

A 10 MW high temperature gas-cooled reactor (HTR-10) was constructed in Institute of Nuclear Energy Technology (INET) of Tsinghua University, China. HTR-10 reached its first criticality successfully in December, 2000 and realized its full power operation in the beginning of 2003. Fabrication technology for HTR-10 spherical fuel element has been established and developed in INET through a lot of R&D activities during the past 20 years. A process known as total gelation process of uranium (TGU) has been developed to prepare UO2 kernel for HTR-10 fuel element in INET. The TGU process combined advantages of both external gelation and internal gelation method of conventional sol-gel process. The sol prescription consists of not only urea, polyvinylalcohol (PVA), tetrahydrofurfuyl alcohol (THFA), but also hexamethylene tetra-amine (HMTA) that is always employed in internal gelation process. The TGU process and facilities are described in this paper. Fuel kernel production for HTR-10 fuel element using this TGU process has completed up to April, 2002. This paper also reported the quality inspection data of kernel production.