The loading of spherical fuel elements has begun at China’s Shidaowan HTR-PM – a high-temperature gas-cooled reactor (HTGR) demonstration project. The unit is scheduled to begin operating later this year.
The first of the graphite spheres was loaded within the reactor’s core on 5 April, China Nuclear Industry 23 Construction Company Limited (CNI23) announced today.
Each of the graphite spheres is 60 millimeters in diameter and weighs about 0.192 kilograms. Every fuel element contains 7 grams of heavy metal. The enrichment of U-235 is 8.5%. The uranium kernels – about 0.5mm in diameter – are coated by three layers of pyro-carbon and one layer of silicon carbon. The coated fuel particles are dispersed in matrix graphite which is 5cm in diameter. Surrounding the fuel-containing graphite matrix is a 5mm thick graphite layer.
CNI23 said the reactor cavity will be filled with a total of 245,318 fuel elements, to a depth of over 11 meters.
The plant will initially comprise twin HTR-PM reactor modules driving a single 210 MWe steam turbine.
A proposal to construct two 600 MWe HTR plants – each featuring three twin reactor and turbine units – at Ruijin city in China’s Jiangxi province passed a preliminary feasibility review in early 2015. The design of the Ruijin HTRs is based on the smaller Shidaowan demonstration HTR-PM. Construction of the Ruijin reactors is expected to start next year, with grid connection in 2021.
China has been actively promoting its HTR technology overseas and has already signed agreements with other countries – including Saudi Arabia, South Africa and the UAE – to consider the construction of HTGR plants. Last August, China Nuclear Energy Engineering Group signed an agreement with Indonesia’s National Atomic Energy Agency (Batan) to jointly develop an HTGR in Indonesia.