HTR-10
10MW High Temperature Gas-Cooled Reactor

The reactor core and the steam generator of the 10MW High Temperature Gas-Cooled Reactor (HTR-10) are arranged side-by-side in two steel pressure vessels, which are connected to each other by a hot gas duct pressure vessel. The HTR-10 uses spherical fuel elements (6cm in diameter) with TRISO coated particles. The reactor equilibrium core contains about 27,000 fuel elements forming a pebble bed. Graphite serves as the main structural material comprising the top, bottom and side reflectors. The ceramic core structures are housed in a metallic core vessel, which is supported on a steel pressure vessel.
Helium is the reactor coolant. After being heated in the pebble bed, helium enters a hot gas chamber in the bottom reflector, and from there, with the reactor temperature, it flows through the hot gas duct to the steam generator.

Completely passive decay heat removal of the HTR-10 under emergency conditions has been designed. A surface cooling system has also been designed.

There are two reactor shutdown systems in the reactor side reflector: the control rod system and the small absorber ball system.