Kaeri moves closer to advanced nuclear tech

Korea is now a step closer to developing more advanced nuclear reactor safety technology, which is considered crucial in producing the next generation of reactors.

The state-run Korea Atomic Energy Research Institute (Kaeri) on Wednesday said it succeeded in slowing and stopping a reactor’s activities using helium and graphite during an experiment.

This experiment was part of the institute’s research project to develop a next-generation reactor called the “very high temperature reactor” (VHTR), which is capable of mass-producing futuristic clean energy sources like hydrogen, as well as electricity.

Kaeri has been developing the VHTR as part of its long-term projects to develop safer, more affordable nuclear power options by 2030.

The VHTR also operates using a ceramic-coated uranium fuel, but the main factor that distinguishes it from currently commercialized reactors is how its reactors are cooled.

The new reactor is designed to automatically cool down by circulating air using helium as a coolant and graphite as a moderator. Regular reactors require machines or a person to manually stop operations.

At the VHTR, if the inner air hits 950 degrees Celsius (1,740 degrees Fahrenheit) or the reactor malfunctions, the air automatically transfers to a reactor vessel, and then to the reactor cavity cooling system (RCCS). The heated air automatically escapes out of the reactor’s chimney, which allows in cold air from the outside, and eventually cools down the reactor to prevent a meltdown.

This mechanism allows a reactor to independently stop itself even if power is knocked out by a natural disaster, which happened during the 2011 incident in Fukushima, Japan.

The Kaeri team will continue to work with the U.S.-based Argonne National Laboratory and the University of Wisconsin to continue developing the RCCS.

BY KIM JI-YOON [kim.jiyoon@joongang.co.kr]