FP chemistry in a high temperature region of LWR under a severe accident, 1; Boron transport behavior in a reactor coolant system

Miwa, Shuhei  ; Imoto, Jumpei ; Miyahara, Naoya; Osaka, Masahiko  

BWR control material, boron, would influence the transport behavior of fission product (FP) such as cesium in a reactor coolant system under LWR severe accident. Thus the boron transport behavior was experimentally investigated by using Test bench for FP release and transport (TeRRa). The analysis results of deposits show that changes in weight of tube increase above 900 K and around 700 K, which would be attributed to chemical reaction with stainless steel and condensation of boron vapor onto stainless tubes, respectively. From these results, it is concluded that the released boron vapor would react with stainless steel and condense in the temperature range of reactor coolant system.