nuclear-news

Tepco to temporarily stop injecting water at Fukushima reactor

November 9, 2018

Tepco to temporarily stop injecting water at Fukushima reactor
The operator of the Fukushima Daiichi nuclear power plant plans to temporarily stop injecting water into one of its damaged reactors to test the cooling of fuel debris.
Tokyo Electric Power Company announced it will conduct the 7-hour test at the No.2 reactor as early as March next year.
The unit is one of 3 in the 6-reactor facility that suffered a meltdown after the March 2011 earthquake and tsunami. The damaged reactors contain a mixture of molten nuclear fuel and structural parts.
TEPCO officials say water injections keep temperatures stable in the 3 reactors at around 30 degrees Celsius.
The planned experiment is aimed at checking how the debris is being cooled. It will be the first time to halt water injections into the reactor since they were stabilized after the accident.
TEPCO’s assessment says the reactor temperature would rise by around 5 degrees per hour if injections were halted by accident. But it says the rise will be limited to about 0.2 degrees per hour when natural heat radiation is taken into account.
TEPCO officials say they will begin cutting back on water injections by around half to 1.5 tons per hour for about a week as early as in January, before halting them completely in March after checking the results.
TEPCO estimates the 7-hour stoppage may raise the reactor temperature by about 1.4 degrees but says water injections will resume if the temperature rises more than 15 degrees.
Company officials say they want to assess changes in the temperature so they can use the data in future emergency cases, including earthquakes and tsunamis.
https://www3.nhk.or.jp/nhkworld/en/news/20181109_10/

November 17, 2018 - Posted by dunrenard | Fukushima 2018 | Fuel Debris, Fukushima Daiichi, Reactor2