Development of a Cs getter contained coated fuel particle layer for high temperature gas cooled reactor

Sasaki, Koei   

We are developing a fuel coating material with a Cs capture function in anticipation of reducing the exposure dose of HTGR plants, improving safety in the event of a primary reactor accident, making the plant more compact and reducing construction costs due to the reduction of shielding wall thickness. Bi and Sb were selected as Cs getter materials. Their simulated Cs trap compounds were formed in the carbon structure and high temperature stability at 1500C was evaluated. Although Bi was precipitated in carbon, the formation of Cs compounds could not be seen. Sb formed a Cs compound (CsSb, etc.) in carbon structure and showed stability at 1500C. Therefore, it was found that Sb has a Cs trap function.