Tepco to start “scanning” inside of Reactor 1 in early February by using muon

Photo : A sample image of muon scanning method inside of a nuclear reactor.

 

On 12/25/2014, Tepco announced they are going to scan inside of Reactor 1 ~ 3 in 2015 by using muon.

Tepco states there is a possibility that molten fuel might be flowing into the narrow parts of RPV (Reactor Pressure Vessel) and PCV (Primary Containment Vessel).

Tepco is currently developing two different technologies to “see through” the crippled reactors by using muon.

One is called “Scanning method”. The detectors are planned to be installed after late in January, to be in operation around the beginning of February.

This method is going to be applied for Reactor 1, which even Tepco assumes no fuel remains in RPV anymore. (cf, Molten fuel might be out of concrete base to directly damage primary containment vessel of Reactor 1 [Le corium pourrait avoir traversé l’embase en béton et endommagé directement l’enceinte principale de confinement du réacteur 1])

 

The other one is called “Scattering method”. This is planned to be in operation from October. This method is applied for Reactor 2.

 

↓ The sample outcome of Scanning method.

Tepco to start scanning inside of Reactor 1 in early February by using muon

↓ The installation of the detector of Scanning method.

2 Tepco to start scanning inside of Reactor 1 in early February by using muon

↓ The detecting image of Scattering method.

3 Tepco to start scanning inside of Reactor 1 in early February by using muon

 

 

http://www.tepco.co.jp/nu/fukushima-np/roadmap/images/d141225_11-j.pdf

http://irid.or.jp/topics/%E5%AE%87%E5%AE%99%E7%B7%9A%E3%83%9F%E3%83%A5%E3%82%AA%E3%83%B3%E3%81%AB%E3%82%88%E3%82%8B%E7%82%89%E5%86%85%E3%81%AE%E7%87%83%E6%96%99%E4%BD%8D%E7%BD%AE%E8%AA%BF%E6%9F%BB%E3%81%AB%E5%90%91%E3%81%91/

http://irid.or.jp/wp-content/uploads/2014/11/140731_03.pdf

 

 

_____

Français :

Tepco va commencer à “scanner” l’intérieur du réacteur 1 début février en utilisant la recherche des muons

 

Photo : Un exemple d’image résultat de la méthode de balayage de recherche des muons dans un réacteur.

 

Le 25 décembre 2014, Tepco avait annoncé qu’ils allaient balayer l’intérieur des réacteurs 1 à 3 en utilisant la recherche des  muons.

Tepco affirme qu’il serait possible que le combustible fondu s’écoule dans les parties étroites de la RPV (Reactor Pressure Vessel = Enceinte Pressurisée du Réacteur) et de la PCV (Primary Containment Vessel = Enceinte de Confinement Primaire).
Tepco développe actuellement deux techniques différentes pour “voir à travers” les réacteurs dévastés en détectant les muons.

L’une est nommée “méthode à balayage”. L’installation des détecteurs est prévue pour fin janvier et être opérationnels vers début février.
Cette méthode sera appliquée au réacteur 1 dans lequel même Tepco considère qu’il n’y a plus de combustible dans la RPV.  (cf. Le corium pourrait avoir traversé l’embase en béton et endommagé directement l’enceinte principale de confinement du réacteur 1)

L’autre est nommée “méthode à dispersion”. Elle est prévue pour être utilisée à partir d’octobre. Elle sera utilisée sur le réacteur  2.

↓ Un exemple de résultat de la méthode à balayage.
Tepco to start scanning inside of Reactor 1 in early February by using muon

↓ Installation des détecteurs de la méthode à balayage.
2 Tepco to start scanning inside of Reactor 1 in early February by using muon

↓ Une image du principe de détection de la méthode à balayage.
3 Tepco to start scanning inside of Reactor 1 in early February by using muon

http://www.tepco.co.jp/nu/fukushima-np/roadmap/images/d141225_11-j.pdf
http://irid.or.jp/topics/%E5%AE%87%E5%AE%99%E7%B7%9A%E3%83%9F%E3%83%A5%E3%82%AA%E3%83%B3%E3%81%AB%E3%82%88%E3%82%8B%E7%82%89%E5%86%85%E3%81%AE%E7%87%83%E6%96%99%E4%BD%8D%E7%BD%AE%E8%AA%BF%E6%9F%BB%E3%81%AB%E5%90%91%E3%81%91/

http://irid.or.jp/wp-content/uploads/2014/11/140731_03.pdf

  1. There’s a reasonably informative article about muon scanning in the New York Times.

    www nytimes.com/2014/06/18/world/asia/measuring-damage-at-fukushima-without-eyes-on-the-inside.html?_r=0

    The scanning technique requires billboard-sized screens to be set up on either side of the substance to be scanned (i.e. melted fuel). That’s fine if the fuel is still in the CV. If the fuel has melted through into the ground it will be impossible to install the lower screen without major excavations, which I suspect are unlikely to happen. It would at least be useful to learn that the fuel has exited the CV. What this would mean in terms of the clean-up is anyone’s guess.

  2. Yep, they will scan to discover the fuel has left the containment….and promptly realize they still have no plan of action to deal with that. Just more pablum for the masses to eat up as we enter into the 2020 PLUlmypics.

  3. And consider, billboard sized screens, the time for exposure for workers…in putting up, moving, testing….in high rads. I sure hope it works..or at least, like YvseLegendaire said, fuel left containment…Check THAT box, fuel is in ground…..now what…

  4. thanks for the info.
    I dont think I understand how it works.
    does heavy-short-life-electron -aka- mueon creation involve radioactive isotopes?
    I mean, do they have to bring radioactive materials TOOfukushima to generate the muon which will then scan the reactor?
    that would be awesome crazy : )
    also I am sorry for ignoring your webpage.
    sry to say that your new design/layout sucks.
    also I am sorry to say that you do not have the “kamikaze” spirit of a true japanese.
    if you were really deep down interested in saving japan you would not think about money.
    there are different ways to keep the information flowing then by running away from your country and taking money for nothing.
    generating electricity from making 10k year lasting garbage is bad .. ut we are humans and I think without calculating that “money” is now just being generated by nuclear “un interrupted” electric power (unlike solar which will work 10000000 years but will not work at night).
    im sry. fix the layout.

  5. muons are constantly being generated when cosmic ray particles hit the atmosphere. They’re part of the natural background radiation.

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About this site

This website updates the latest news about the Fukushima nuclear plant and also archives the past news from 2011. Because it's always updated and added live, articles, categories and the tags are not necessarily fitted in the latest format.
I am the writer of this website. About page remains in 2014. This is because my memory about 311 was clearer than now, 2023, and I think it can have a historical value. Now I'm living in Romania with 3 cats as an independent data scientist.
Actually, nothing has progressed in the plant since 2011. We still don't even know what is going on inside. They must keep cooling the crippled reactors by water, but additionally groundwater keeps flowing into the reactor buildings from the broken parts. This is why highly contaminated water is always produced more than it can circulate. Tepco is planning to officially discharge this water to the Pacific but Tritium is still remaining in it. They dilute this with seawater so that it is legally safe, but scientifically the same amount of radioactive tritium is contained. They say it is safe to discharge, but none of them have drunk it.

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