50-day long-term high-temperature operation was attained by the HTTR of Japan Atomic Energy Agency

Takada, Shoji; Nishihara, Tetsuo ; Iyoku, Tatsuo; Nakazawa, Toshio; Komori, Yoshihiro 

The 50-day long-term high-temperature operation was successfully attained by the High Temperature Engineering Test Reactor (HTTR) of the Japan Atomic Energy Agency (JAEA), the rated thermal output of 30 MW and the maximum reactor outlet temperature of 950 C, first in the world. The operation was started on January 22 and accomplished on March 13 this year. Many data on the characteristics of reactor core physics and thermal hydraulics, the impurity control in coolant helium gas, the performance of high temperature components and the core internal structure integrity was acquired to establish the HTGR technology basis. The HTGR is expected as a green-house gas emission free heat source of innovative thermo-chemical hydrogen production system. It was demonstrated first in the world that high temperature gas can be stably supplied for long term period. In the next stage, the tests will be carried out to confirm the applicability and the extreme safety performance of HTGR by the HTTR.