Operation, test, research and development of the high temperature engineering test reactor (HTTR). FY2007

The High Temperature Engineering Test Reactor (HTTR) constructed at the Oarai Research and Development Center of the Japan Atomic Energy Agency (JAEA) is the first high-temperature gas-cooled reactor (HTGR) in Japan. The HTTR is a graphite-moderated and helium gas-cooled reactor with 30MW of thermal power. The full power operation of 30MW was attained in December 2001, and then JAERI (JAEA) received the commissioning license for the HTTR in March 2002. Since 2002, we have carried out rated power operations, safety demonstration tests and several R and Ds, etc. In April 2004, the HTTR conducted the high-temperature test operation with outlet coolant temperature of 950degC. In fiscal year 2007, we have carried out long-term (30 days) operation to accumulate operational data for HTGR developments. Periodical inspections, exchange of filter of primary gas circulators and in-service inspection of the reactor pressure vessel were also conducted, and manufacturing of control rod for exchange was started. This report summarizes activities and results of HTTR operation, maintenance, and several R and Ds, which were carried out in the fiscal year 2007. (author)