HBK project high temperature reactor fuel cycle. Qualifying Spherical HTR Fuel Elements for Advanced Applications. Technical Note

1. Introduction: In the Federal Republic of Germany two High Temperature Reactors (HTR) with pebble bed cores are in operation at the present: the AVR (15 MWe) at Jülich since 1968 and the THTR-300 (300 MWe) at Schmehausen since 1985. Based on the positive experience with these experimental and prototype reactors, the commerical follow-up HTR will be introduced in the near future. Development and qualification of a high performance low cost spherical fuel element are most important prerequisites for these HTR's. The objective of the present fuel element development programme is twofold: Firstly, it has to provide a fuel element which fulfils all the operational requirements of future HTR's. Secondly, it has to enable the fuel element manufacturer to install a production line for increased throughput, where high quality fuel elements can be produced economically. In order to concentrate these efforts it was decided that a unique fuel element for all applications (electricity, process steam, process heat) should be developed.