Hydrogen Fix For Japanese Nuclear Reactors


Areva is to fit all 23 Japanese pressurized water reactors with hydrogen recombiners that help to prevent the explosive gas building up in emergency situations.

The French company announced a contract to provide a bulk order of its passive autocatalytic recombiners. The devices use catalytic oxidation to turn traces of hydrogen into steam, a process that works constantly and requires no power. They will be fitted in the reactor unit containment vessels to help prevent hydrogen explosions and “preserve the integrity of the reactor,” said Areva.

Many nuclear operators installed systems to manage hydrogen after the partial core melt at Three Mile Island in 1979. Unfortunately, this was not the case in Japan. During the accident at Fukushima Daiichi last year, many hours without power for cooling water pumps saw nuclear fuel in the cores of units 1, 2 and 3 overheat to the point that zirconium fuel cladding oxidised in the presence of steam, producing hydrogen and oxygen. At units 1 and 3 this was able to escape the containment and concentrate in the tops of the buildings, where it eventually exploded and caused extensive physical damage to those units as well as unit 4.

Areva said it will install more than 100 of its devices at the Japanese pressurized water reactors, which make up 23 of the country’s 50-reactor fleet. The reactor type is used at the following Japanese nuclear power plants: Ikata, Mihama, Ohi, Sendai, Takahama, Tsuruga, Tomari and Genkai.

World Nuclear News

World Nuclear News is an online service dedicated to covering developments related to nuclear power. Established in 2007, WNN has grown rapidly to welcome over 40,000 individual readers to the website each month, while its free daily and weekly emails both reach more than 16,000 people. These figures represent a broad audience that includes not only nuclear professionals but also journalists, researchers, opinion leaders, policy-makers, and the general public.

Leave a Reply

Your email address will not be published. Required fields are marked *