Development of a decay heat estimation method for various fuel debris

Sakamoto, Masahiro ; Terashima, Kenichi  ; Matsumura, Taichi ; Fujita, Manabu*; Okumura, Keisuke 

It is important to estimate the decay heat of the fuel debris at the Fukushima Daiichi Nuclear Power Station in examining the cooling method and evaluating the heat removal of the debris transport and storage containers for debris retrieval. However, fuel debris is not easy to estimate the decay heat because the composition of nuclides is not clear like the spent fuel whose combustion history is clear. Therefore, we developed a method to easily calculate the decay heat of debris considering parameters such as debris weight, burnup, nuclide release rate, and elapsed time etc.