Validation of system analysis code with HTTR thermal load fluctuation test data (non-nuclear heating) and evaluation of reactor temperature behavior during upsets in hydrogen production plant

Honda, Yuki; Sato, Hiroyuki  ; Nakagawa, Shigeaki  ; Takada, Shoji; Tochio, Daisuke ; Sakaba, Nariaki ; Sawa, Kazuhiro

Japan Atomic Energy Agency (JAEA) proposed a draft safety requirement, which consists of the requirements for constructing a H plant under conventional chemical plant regulations as well as the requirements for collocation of a nuclear facility and a H plant. One of the key requirements is to maintain reactor normal operation condition during every possible condition in the H plant. In order to show that the requirement can be reasonably achieved, a system analysis code is validated with the HTTR experimental data obtained in January 2015. The validated code is applied for the evaluation of a postulated abnormal event in H plant to be connected to the HTTR. The results showed that the evaluation items such as reactor power and reactor outlet coolant temperature do not exceed evaluation criteria. As a conclusion, a feasibility of H plant construction under non-nuclear regulations is validated by showing that the stable reactor operation can be achieved against temperature transients induced by abnormal conditions in the H plant.