Technology to look inside Fukushima reactors faces challenge

Technology to look inside Fukushima reactors faces challenge
Muon drift tubes are seen on an equipment shown to journalists by Toshiba officials at its research center in Yokohama near Tokyo Friday, March 27, 2015. Toshiba says the drift tubes detect muons and send data to electronic boards to map an image of the melted fuel at the Fukushima reactors, using subatomic particles called muons. The cutting-edge technology was billed as a way to decipher where exactly the morass of nuclear fuel might sit at the bottom of the Japanese power plant that went into multiple meltdowns four years ago. But what went wrong, even in a simple demonstration for reporters Friday for the 500 million yen ($5 million) project, was a sobering reminder of the enormous challenges that lie for the decommissioning of Fukushima Dai-ichi. (AP Photo/Emily Wang)

The cutting-edge technology was billed as a way to decipher where exactly the morass of nuclear fuel might sit at the bottom of reactors in the Japanese power plant that went into multiple meltdowns four years ago.

But what went wrong, even in a simple demonstration for reporters Friday for the 500 million yen ($5 million) project, was a sobering reminder of the enormous challenges that lie ahead for the decommissioning of Fukushima Dai-ichi.

Muons are cosmic-ray subatomic particles so tiny they go through almost anything except for so-called heavy elements like uranium and plutonium used for nuclear fuel. They can help present a picture of what's inside an object, similar to the way doctors use X-rays, and have been used to study the Egyptian pyramids, the insides of volcanoes and ship cargo at ports.

The ideal scenario goes like this: Two giant walls more than two stories high will be set up right next to each reactor to shoot out muons so that data from how the muons scatter after hitting what's inside, picked up by sensors, can be analyzed. Such image-mapping is possible because muons will bend at different angles, depending on the material they hit.

But a programming glitch could not be fixed in time for Friday's demonstration at Toshiba's research center, near Tokyo, to show any image, even a mock-up, from the muons.

All reporters got to see was the huge equipment, metal with lots of wirings and blinking little lights, in a giant garage-like building, and on its side, not straight up as it would be when put to use at the plant.

Technology to look inside Fukushima reactors faces challenge
A Toshiba official walks by an equipment shown to journalists at its research center in Yokohama near Tokyo Friday, March 27, 2015 to map an image of the melted fuel at the Fukushima reactors, using subatomic particles called muons. The cutting-edge technology was billed as a way to decipher where exactly the morass of nuclear fuel might sit at the bottom of the Japanese power plant that went into multiple meltdowns four years ago. But what went wrong, even in a simple demonstration for reporters Friday for the 500 million yen ($5 million) project, was a sobering reminder of the enormous challenges that lie for the decommissioning of Fukushima Dai-ichi. (AP Photo/Emily Wang)

Experts have long said that what's crucial for decommissioning is getting an image of the nuclear fuel after the March 2011 tsunami crippled backup generators at Fukushima Daiichi, setting off the worst nuclear catastrophe since Chernobyl.

No one knows where the molten fuel debris lies, and in what shape or state. Tokyo Electric Power Co., which operates Fukushima Dai-ichi, has said it likely sank to the bottom of the plant. But the fuel could have dropped even beyond.

Tadashi Yotsuyanagi, an official in charge of the muon project at Toshiba Corp., acknowledged radiation would be an obstacle for people doing the construction work to set up the walls. High exposure to radiation is unhealthy, sometimes fatal.

But once the image is relayed to a distant computer, studying that won't require people to be near radiation, the plus of using muon technology for studying nuclear plants, according to Adrian Hillier, an expert on muons at the STFC Rutherford Appleton Laboratory in the U.K.

Toshiba plans to start setting up the "muon trackers" at Fukushima Dai-ichi sometime after October but before March 2016. The Japanese electronics giant, which owns Westinghouse Electric Co. of the U.S., is one of the main companies behind Japan's nuclear industry, including Fukushima Dai-ichi. Toshiba has been working on the muon technology from right after the disaster, with the help of the Los Alamos National Laboratory in the U.S.

Technology to look inside Fukushima reactors faces challenge
Electronic boards of an equipment is shown by Toshiba officials at its research center in Yokohama near Tokyo Friday, March 27, 2015 to map an image of the melted fuel at the Fukushima reactors, using subatomic particles called muons. The cutting-edge technology was billed as a way to decipher where exactly the morass of nuclear fuel might sit at the bottom of the Japanese power plant that went into multiple meltdowns four years ago. But what went wrong, even in a simple demonstration for reporters Friday for the 500 million yen ($5 million) project, was a sobering reminder of the enormous challenges that lie for the decommissioning of Fukushima Dai-ichi. (AP Photo/Yuri Kageyama)

But Yotsuyanagi acknowledged the technology would not be able to get the complete image toward the bottom of the reactor. He also said heavy radiation in the area would throw the sensors off, although that can be figured into the calculations of the scattered muons.

David Ireland, a professor who heads the Nuclear Physics Group at the University of Glasgow, said muons may be the only way to probe inside atomic reactors.

"There are not really any other non-invasive options that will allow inspection," he said in an email.

Technology to look inside Fukushima reactors faces challenge
Journalists look at an equipment shown by Toshiba officials at its research center in Yokohama near Tokyo Friday, March 27, 2015 to map an image of the melted fuel at the Fukushima reactors, using subatomic particles called muons. The cutting-edge technology was billed as a way to decipher where exactly the morass of nuclear fuel might sit at the bottom of the Japanese power plant that went into multiple meltdowns four years ago. But what went wrong, even in a simple demonstration for reporters Friday for the 500 million yen ($5 million) project, was a sobering reminder of the enormous challenges that lie for the decommissioning of Fukushima Dai-ichi. (AP Photo/Yuri Kageyama)

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Cosmic-ray muon technology to be used to image debris inside Fukushima Dai-ichi reactors

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Mar 27, 2015
We have nuke-lovers right here in America who would volunteer to go save us.

Don't we?

We already know there is no fuel left in Unit One, and almost none left in Unit Two,. Unit Three destroyed itself after a hydrogen conflagration caused a nuclear criticality and a detonation.

Mar 27, 2015
Do the outsiders here know that nuke plants require continual cooling, even when completely off-line? Do they know the waste fuel has to be kept cooled for decades, or it can conflagrate and spread its deadly radiation all over the world?

Do they understand the tremendous costs of a minute of downtime, because of the cooling and staffing required?

I think not. It may not be in Wiki.

Mar 27, 2015
after a hydrogen conflagration caused a nuclear criticality and a detonation
-But mr sloganeer I have already shown you that H2 can produce explosions which propagate at detonation velocities, even without containment.

Further, prompt criticalities would only very rarely produce the kind of conditions exceeding deflagration velocities. Because they are very sloppy and chaotic events indeed.
cont>

Mar 27, 2015
Its obvious youve gotten the concept 'nuclear detonation' confused with 'detonation' as used to describe the velocity of the shock wave in conventional explosions.

"deflagration, the combustion or reaction wave propagates at a velocity less than the speed of sound"

"detonation, the combustion or reaction wave propagates at a velocity faster than the speed of sound"

"the term explosion... does not refer to nuclear explosions. Nuclear detonation requires a mass far beyond critical of weapons-grade fissionable materials (much higher-grade than are used in power plants), under extremely demanding conditions of pressure and uniformity... so difficult to produce through purposeful engineering... the effects of criticality would disrupt the assembly long before such a mass could be formed..."

-Do you require this info in an even simpler form? I dont think thats possible. Perhaps you should try reading slower. And avoid reading sources by people only a little smarter than you.

Mar 28, 2015
why sound waves could not be utilized to create a 3D map of the soil?

Mar 28, 2015
Those without any knowledge whatever in any topic dies themselves no service by bleating words they do not understand and phrases out of context.

otto, I know the difference between deflagration and detonation already, which is why I brought it up. Apparently, you did not. It is the difference between a hydrogen explosion and a criticality, for one.

Why can't you just accept I am correct, and you are just an old guy with mental problems, which manifest themselves in your hateful mania?

Let's discuss what you nuke apologists are going to do with those THREE blobs of Coruim, where none were even possible. No entries in Wiki for that, otto.

Mar 28, 2015
Where are our nuclear apologists? They need YOU at Fukushima. They are running out of people to dose there, and that is no joke.

Otto,if you go see even one nuclear plant, go to Fukushima, and see the things about which I educated you. Talk to some engineers there, and find out they have completely different jobs and areas of expertise, . . not at all like you imagined.

You can learn a lot from experience.

Mar 28, 2015
The argument above regarding detonation versus deflagration is important: It is the difference between a conventional explosion and one with MUCH more energy, sufficient to exceed the speed of sound.

Hydrogen explosions are deflagrations, or fast-burning, but not supersonic. But their shockwaves can be used to increase the density of the nuclear materials, like they are in real nuclear weapons, and result in imperfect criticalities.

Look at the differences between the other explosions and that of Unit Three, spiked with Plutonium. And since then, we have had symptoms of other criticalities, as the Corium moves around, who-knows-where, in Unit One. All of the fuel and materials are melted out of the bottom of that reactor vessel.

We have NO WAY of handling that nasty stuff, and cannot even view it, for the radiation, which even kills our electronics. They honestly do not know what to do.

Mar 28, 2015
difference between a hydrogen explosion and a criticality
Ahaahaaaa you STILL have them confused. A chemical detonation is NOT a nuclear detonation.
difference between a conventional explosion and one with MUCH more energy, sufficient to exceed the speed of sound... Hydrogen explosions are deflagrations, or fast-burning, but not supersonic
Ahaahaaaa look at the Professor. The wizard on your website yes?

Conventional explosions can propagate faster than the speed of sound. H2 can produce detonations, even when unconfined, as I SHOWED you.

Are you really that fucking DENSE?
shockwaves can be used to increase the density of the nuclear materials
No. H2 explosions do not produce near the amount of force necessary to compress Pu to prompt criticality. This takes specialized design and high explosives.

"...even "weapons grade" Pu-239 is contaminated with a small amount of Pu-240, which has a strong propensity toward spontaneous fission."

Mar 28, 2015
Yes, otto,and it is impossible for nuclear reactors to melt down. And nuclear power is too cheap to meter. I have heard all of them.

The criticality of Unit Three is not my determination, but those from sources I trust, with copious explanations of proof using decay paths. What do you have, besides a Wiki paragraph, not concerned with Fukushima?

Mar 28, 2015
Muons are cosmic-ray subatomic particles so tiny they go through almost anything except for so-called heavy elements like uranium and plutonium used for nuclear fuel.

This may be the dumbest description of muons I've ever seen.

As for the technology, this is a very cool idea. I'm also impressed that it can be implemented so cheaply. Kudos for some real cleverness on the part of the guys who came up with this.

Mar 29, 2015
Yes, otto,and it is impossible for nuclear reactors to melt down. And nuclear power is too cheap to meter. I have heard all of them.

The criticality of Unit Three is not my determination, but those from sources I trust, with copious explanations of proof using decay paths. What do you have, besides a Wiki paragraph, not concerned with Fukushima?
So POST your idiot sources or STFU. Are your sources the ones that taught you this bullshit?
Hydrogen explosions are deflagrations, or fast-burning, but not supersonic
-or did you gain that valuable knowledge as a Validation Form-Filler-Outer Engineer?

Mar 29, 2015
No, otto, I got it from nuclear experts. You will not believe it,but most engineers work in vastly different fields, with vastly different requirements, mostly specific. Those of you in offices who only passed papers and gas will not understand that.

When we get together, we dicscuss things like I do with you. Here, I made the incorrect assumption you were a fellow professional, not a weird crank.

Mar 29, 2015
No, otto, I got it from nuclear experts
So are these people you met on the street? Wheres your link or its obvious you made it up like the rest of your crap. Ask you why they didnt tell you about H2 detonation.

"Detonation velocities were measured in mixtures of hydrogen and oxygen containing 25 to 75
mole % hydrogen at initial temperatures from 160' to 580'K. and initial pressures from M to
2 atm. The measurements were made in a number of tubes of different diameter to permit
extrapolation to a tube of infinite diameter."
http://deepblue.l...quence=1

-Maybe they thought it was beyond your level of expertise.

Mar 29, 2015
"beyond your level of expertise"
----------------------------------------------------

That's laughable, coming from pseudonym otto-wiki. Do you actually have any yourself? I showed yo some of mine, and you could look them up, but you do not have any of which you are proud.

From what expertise or experience or education do you challenge me? What have you learned, accomplished, or can admit?

Mar 29, 2015
Hoping to sort fact from fiction I read a bit more. Found some stuff about the tsunami being a man made event triggered by a nuclear device. Atomic weapons disguised as cameras inside the buildings causing the explosions. Also the usual 'its a cover up' and the fuel went bang loonies. This stuff makes some of my flights of fantasy look realistic!

Mar 29, 2015
" Found some stuff about the tsunami being a man made event triggered by a nuclear device"
-------------------------------------

Inevitable, I suppose. Sorry James Bond didn't get to it first.

Mar 30, 2015
"beyond your level of expertise"
----------------------------------------------------

Hey gkam-bullshit-wiki
That's laughable, coming from pseudonym otto-wiki. Do you actually have any yourself? I showed yo some of mine, and you could look them up, but you do not have any of which you are proud.
Why are you proud of experience and education that makes you continue to insist that H2 can't achieve detonation when the proof that it can is shoved in your face? That's something to be ashamed of I think.
From what expertise or experience or education do you challenge me? What have you learned, accomplished, or can admit?
Irrelevant you moron. What if those assets of yours makes you think you can make up utter bullshit and get away with it?

Every day george. I hope you're enjoying the daily embarrassment of being outed as the phony you are.

Mar 30, 2015
High exposure to radiation is unhealthy,

No. Really?

why sound waves could not be utilized to create a 3D map of the soil?

Seismics/infrasound don't have the resolution necessary. Ultrasound doesn't have the penetration depth necessary.


Mar 30, 2015
Otto, you're hilarious. I should have invented you myself.

Mar 30, 2015
This is for otto and Eikka:
http://www.thetim...4978.ece

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